Regulation of cholesterol biosynthesis by normal and leukemic (L2C) guinea pig lymphocytes. The cholesterol production of guinea pig leukemic (L2C) lymphocytes preceeds at greater than 30 times the rate found in normal cells. Fatty acid biosynthesis is also enhanced in L2C cells. Exposure of L2C cells to cholesterol/lecithin liposomes does not depress their sterol biosynthesis, in contrast to the behavior of normal lymphocytes [Philippot, J.R., Cooper, A.G. & Wallach, D. F. H. (1975) Biochim. Biophys. Acta 406, 161-166]. However, 25-hydroxycholesterol, an inhibitor of hydroxymethylglutaryl-CoA reductase (NADPH) [mevalonate: NADP+ oxidoreductase (CoA-acylating), EC 1.1.1.34], the rate limiting enzyme in cholesterogenesis, and 25-hydroxycholecalciferol, a biologically potent form of vitamin D3, block sterol biosynthesis of both normal and L2C lymphocytes [Philippot, j.r., cooper, A.G. & Wallach, D.F.H. (1976) Biochem. Biophys. Res. Commun. 72, 1035-1041]. Moreover, both cell types exchange cholesterol equivalently with cholesterol/lecithin liposomes. The only difference in sterol biosynthesis observed between the two cell types is in the temperature response of the enzyme. Arrhenius plots of this enzyme activity exhibit a prominent discontinuity at about 24 degrees in the case of normal cells, but none in the case of L2C. The activation energies for L2C cells and normal cells, above the normal cell transition temperature, were not significantly different. All of the data suggest that the regulatory defect in L2C lymphocytes arises from a deficiency in these cells' internal membranes.


Minimal length of the lactose operator sequence for the specific recognition by the lactose repressor. A number of specific duplex DNA sequences which correspond to varying lengths of the lactose operator region have been synthesized by a combination of chemical and enzymatic methods. Repressor binding studies on these synthetic duplex operator molecules show that all the nucleotides essential for full lactose operator-repressor interactions are included in a 17-nucleotide-long duplex DNA that constitutes the minimal recognition sequence for this DNA-protein interaction.


Three-dimensional structure of neurotoxin a from venom of the Philippines sea snake. The crystal structure of neurotoxin a from the venom of Philippines sea snake Laticauda semifasciata has been determined at 2.5 A resolution by x-ray diffraction. Comparison with the structure of neurotoxin b from the same source indicates that the two toxins differ only by substitution at His 26. Earlier chemical work had suggested a difference in chain length and considerable differences in amino acid composition. The difference between our a and b toxins is the same as that reported from sequence analysis for the related erabutoxins a and b from Japanese sea snake, and suggests that the Philippines toxin may be identical to erabutoxin. The replacement of His 26 by a shorter side-chain in toxin a has no effect on the structure of the rest of the molecule. In particular, the protruding loop, which we believe interacts with the acetylcholine receptor, is not affected, even though His 26 is in the loop.


Translation of melittin messenger RNA in vitro yields a product terminating with glutaminylglycine rather than with glutaminamide. Melittin messenger RNA from queen bee venom glands has been translated in a cell-free system from wheat germ. A product larger than promelittin is formed which has the carboxy-terminal sequence-Gln-Gln-GlyCOOH. Melittin and promelittin from venom glands terminate in -Gln-GlnCONH2. The possible role of the extra glycine residue in the formation of a COOH-terminal amide via a transamidase-like reaction is discussed.


Excision repair of benzo[a]pyrene-deoxyguanosine adducts in baby hamster kidney 21/C13 cells and in secondary mouse embryo fibroblasts C57BL/6J. The formation and excision of benzo[a]pyrene-deoxyguanosine adducts in metabolizing baby hamster kidney cells (21/C13) and secondary mouse embryo fibroblasts (C57BL/6J) was investigated. Both diastereomeric adducts, N2-(10-(7beta,8alpha,9alpha-trihydroxy-7, 8, 9, 10 tetrahydrobenzo[a]-7,8,9,10-tetrahydrobenzo[a]pyrene)yl)deoxyguanosine, were detected in both cell lines and both cell lines were capable of excising these lesions, albeit with low efficiency.


Nucleotide sequence surrounding a ribonuclease III processing site in bacteriophage T7 RNA. We have determined a nucleotide seuqence of 87 residues surrounding a ribonuclease III (endoribonuclease III; EC 3.1.4.24) processing site in the bacteriophage T7 intercistronic region between early genes 0.3 and 0.7. The structural requirements necessary for proper recognition and cleavage by RNase III are discussed. In addition, other structural features characteristic of this intercistronic boundary are described.


The future of the visual sciences in Rhode Island: an introduction.


Ophthalmology in medical student education: philosphy, content, and process.


The relationship of ophthalmology to other science modalities.


A department of ophthalmology: a personal view.


The future of ophthalmology.

The future of ophthalmology.


The visual sciences at Brown University - one possible approach.


Future of visual sciences in Rhode Island. VI. Another possible approach.


Effect of topically applied neutrophil leukocyte extract on normal gingiva of dogs. Seven beagle dogs were used to study the gingivitis-inducing potenial of a topically applied neutrophil leukocyte extract and to compare the vascular and cellular reactions with those induced by plaque extract applied in an identical manner. In four dogs neutrophil extract was applied onto the marginal gingiva in one jaw quadrant while Gey's medium was applied to the contralateral gingival units. In the remaining three dogs plaque extract and Gey's medium, respectively, were applied in the same way. After 6.5 h of topical application colloidal carbon (1 ml/kg bodyweight) was injected into a leg vein and after a further 1.5 h biopsies were obtained from the experimental regions. The results show that topical application of an extract from neutrophils induces both an increase in the number of crevicular leukocytes and an enhanced vascular permeability. As in previous studies plaque extract was found to promote the emigration of leukocytes and to alter the permeability of the dentogingival vessels. The vascular and cellular reactions were, however, more pronounced after application of plaque extract than after neutrophil extract.


Histologic demonstration of bacteria subjacent to dental restorations. Sections of demineralized teeth which had received experimentally inserted restorations using a variety of materials have been stained according to the Brown and Brenn technique. Conventional cavity preparations had been made in intact areas and the cavities were dried gently without additional treatment prior to restoration. Different restorative materials were used and the teeth were extracted after 3-117 days' observation. No bacteria could be demonstrated at the dentin/filling interface or in the dentin if zinc oxide/eugenol, Ca(OH)2 mixed with water or corticonsteroid/antibiotic preparations were employed as base or lining materials. A few bacteria were found subjacent to two of seven unlined amalgam fillings and subjacent to three silicate restorations which had been lined with a polymeric material.


Variable expressivity of Crouzon's syndrome within a family. Three individuals in two generations affected with Crouzon's syndrome are reported. The proband, a 10-year-old boy, had been diagnosed until the age of 4. His 3-year-old sister had not been diagnosed previously and his mother was unaware of having the syndrome and had never received any genetic counseling. The individuals are reported with emphasis on clinical and roentgencephalometric variation. The ultimate goal in teratolgoy is prevention. Currently one of the most important factors related to prevention is genetic counseling in conditions with well-documented modes of inheritance. The present report describes how the variable expressivity of Crouzon's syndrome within a family had caused diagnostic problems and consequently had delayed genetic counseling.


Operational definitions of mandibular morphogenetic and positional rotations. A material of 30 patients with metallic implants was used in a longitudinal study, based on lateral headplates, of the mandibular rotational pattern. The complexity of the rotational phenomenon in the mandibular rotation has necessitated the proposal of some operational definitions: morphogenetic and positional rotations of the mandible. A relationship has been established between the variation of the gonial angle and the variation of both morphogenetic and positional rotations of the mandible. A relationship has been established between the variation of the condylar growth direction and the variation of both morphogenetc and positional rotations of the mandible: this relationship is the strongest when the morphogenetic rotation of the corpus is considered.


Direction and intensity of mandibular rotation in the sagittal adjustment during growth of the jaws. A material of 22 patients with metallic implants in both jaws has been used to study, longitudinally on lateral headplates, the relationship between the degree of mandibular rotation, the difference in amount of growth of both jaws, represented by the value (E), and the sagittal intermaxillary relationship (G). It has been established that the variation of sagittal intermaxillary relationship and the variation of the degree of mandibular rotation are two phenomena presenting a "balance mechanism" when related to the value (E). The different combinations of these three variables during mandibular growth are proposed, represented in diagrams. This study reveals that several possible mandibular responses correspond to a single given initial condition.


Bite force and oral function in patients with osseointegrated oral implants. The function of the masticatory system was analyzed in 19 patients (13 women and 6 men), aged 39 to 68, randomly selected from a group of 165 patients who had been treated with osseointegrated oral implants within the last 7 years (average 3.5 years). The patients were well satisfied with the functional capacity of their implant reconstructions, especially compared with the poor function before treatment. According to the clinical examination, all but one patient had no or only mild symptoms of dysfunction of the masticatory system. Three bite-force levels were recorded. The mean value for gentle biting was 15.7 N, for biting as when chewing 50.1 N, AND FOR MAXIMAL BITING 144.4 N. The patients could thus well discriminate between the different bite-force levels, and the maximal values are much higher than those in persons with removable dentures.


The incidence and characteristics of acute myeloid leukaemia arising in Hodgkin's disease. In 201 consecutive patients with Hodgkin's disease treated from 1964 through 1975 with intensive irradiation and/or combination chemotherapy 3 cases of acute myeloid leukaemia were observed. The observed number of cases was 75 times over the expected (P less than 0.01). An analysis of 47 reported cases of acute myeloid leukaemia arising in Hodgkin's disease shows that these cases differ considerably from 'spontaneous' cases of acute myeloid leukaemia by appearing in a much younger age group, by a very poor response to anti-leukaemic chemotherapy, and by a relatively low male/female ratio (0.84). The intensification of radiotherapy and cytostatic therapy of Hodgkin's disease during the last decade is considered the explanation of the increased incidence of acute myeloid leukaemia in these patients.


The status of interferon.

The status of interferon.


Problem solving in diagnostics and therapeutics of neurology. A series of 24 lectures. Lecture No. 16. The treatment of "chemophilia" (alcoholism, drug dependency).


Pain: current concepts and management.

Pain: current concepts and management.


Granulocyte transfusion therapy in children. A prospective study of 45 granulocyte transfusions in children using continuous flow centrifugation is reported. During 13 episodes of proven or presumed infection, only two children failed to show a favorable response to granulocyte transfusion. The neutropenic child shows a significantly increased absolute granulocyte count one hour after transfusion. The granulocyte counts at one hour after transfusion are inversely proportional to the child's size. A child with chronic granulomatous disease who had documented Nocardia asteroides sepsis and pneumonia exhibited complete recovery following granulocyte transfusion. Dramatic responses to the nonrandom use of granulocyte transfusion have been observed in children with major gram-negative bacterial infections. Endorsement of granulocyte transfusion for instances of presumed, but unproven, infection in the neutropenic child will require randomization to control the variables of antibiotic therapy and bone marrow remission.


The problem drinker dentist.

The problem drinker dentist.


How to get the most mileage out of your insurance premium dollar?


Effectiveness assessment. A survey of the TDA.


Diagnosis and treatment of canine hematopoietic neoplasms.


Run-away pacemaker: diagnosis and management.


How people get well through psychiatry.

How people get well through psychiatry.


Phagocytosis of hematopoietic cells by blast cells in blast crisis of chronic myelocytic leukemia.


Cell-mediated immunity in multiple sclerosis. The blastogenic response of MS lymphocytes to a group of paramyxovirus antigens and to phytohemagglutinin was investigated. Comparative studies were performed in a selected group of patients before and after transfer factor therapy. There was no blastogenic response of lymphocytes to the paramyxovirus antigens tested in MS patients and normal controls, as measured by the incorporation of 14C thymidine. The stimulation index was below 2.5 even after transfer factor therapy. Lymphocyte transformation induced by PHA appeared significantly depressed in the MS patient group before transfer factor therapy when compared with the normal control group. The presence of serum factors that may depress PHA-induced lymphocyte transformation were looked for and not found. Following transfer factor therapy, an increase of the PHA response was observed in the MS group, such that a statistically significant difference in response compared with the normal control group was no longer present.


The relationship between measles virus-specific antibodies and oligoclonal IgG in the cerebrospinal fluid from patients with subacute sclerosing panencephalitis and multiple sclerosis.


Immunoglobulin abnormalities in spinal fluid in multiple sclerosis.


Virus antibody levels in serum and cerebrospinal fluid specimens from patients with optic neuritis. Virus antibody levels in serum specimens from 77 patients with optic neuritis (ON) were compared with those in healthy controls which had been matched with regard to sex, age and place of residence. A group of 58 patients with various neurological diseases other than multiple sclerosis (MS) or infectious diseases of the central nervous system (CNS) served as a second control group. The ON patients had significantly higher measles antibody titers in serum than the two control groups in both measles HI and HLI tests. Tests of cerebrospinal fluid (CSF) specimens revealed similar differences between ON patients and controls. Tests for antibodies to other viruses showed no statistically significant differences between ON patients and controls. There were several ON patients with normal serum/CSF albumin ratios but low serum/CSF IgG and measles antibody ratios. An increase in measles antibody CSF titers was observed during the study time in two ON patients. The results support the hypothesis that local production of measles antibodies takes place in the CNS of some patients with ON as has been earlier suggested to occur in patients with MS.


Use of a radioimmune assay in detection of measles antibodies in cerebrospinal fluid and serum. Evidence that different structural components of the measles virus may act as antigens has been demonstrated by the serologic methods of hemagglutination inhibition, hemolysin inhibition and nucleocapsid complement fixation. Using radioiodinated measles viral antigens, an immune precipitation assay has been designed which is capable of discriminating varying reactivities to measles viral structural components in serum or CSF and of differentiating whether IgG and IgM antibody is involved. This technic has been applied to the study of measles antibodies in CSF and sera of patients with multiple sclerosis (MS) and other neurologic diseases. From data presented here, it is found that both groups of patients have individual reactivity to measles proteins, present in CSF  and serum, while three normal CSF sample were not found to have such antibodies.


Immunotherapy in infectious disease, autoimmunity and cancer. The clinical and immunologic effects of transfer factor and of levamisole were evaluated in over 200 patients with a variety of diseases. With transfer factor, the most encouraging results were observed in patients with the Wiscott-Aldrich syndrome, chronic mucocutaneous candidiasis, coccidioidomycosis, Behcet's disease and malignant melanoma. With levamisole, the most promising results were observed in patients with recurrent aphthous stomatitis, rheumatoid arthritis and herpes simplex infections, especially ocular herpes. Immunologically, transfer factor usually caused conversion of skin test reactivity and conversion of in vitro tests of cellular immunity as well, whereas levamisole caused increases in skin test reactivity without a parallel change in in vitro para meters, suggesting that the two agents may have different mechanisms of action. In a limited number of patients with multiple sclerosis, reactivity to three viral antigens was found to be lower than that in normal subjects, as measured by lymphocyte stimulation. Following levamisole therapy, this reactivity increased to normal levels, but the patients did not show clinical benefit.


Cell mediated immunity to viral antigens in multiple sclerosis.


On a subordinate role for genetic markers in multiple sclerosis on the Faeroes.


The aetiology of MS-genetic aspects.

The aetiology of MS-genetic aspects.


Immunological aspects of multiple sclerosis.


Maxillary rotation during human growth: annual variation and correlations with mandibular rotation. A metal implant study. For a longitudinal study of the maxillary rotation, based on lateral headplates, a material of 22 patients with metallic implants in both jaws has been used. It has been established that the degree of maxillary rotation shows variations in direction and in intensity each year. It is smaller, in absolute value, than the degree of mandibular rotation. Due to the fact the direction of the maxillary and mandibular rotations are not always the same, it appears that the interaction between the maxillary and mandibular rotations plays an important role in the vertical and sagittal relationships of both jaws.


Human saliva kallikrein. Biological properties of saliva kallikrein isolated by use of affinity chromatography. Kallikrein purified from whole human saliva was studied for its influence on leucocyte migration and kinin generating capacity. The kallikrein had a leucotactic effect on neutrophil leucocytes in the presence of 2% serum albumin. This leucotactic effect could be inhibited by Trasylol. The study showed that kallikrein liberated kinin from the precursor kininogen in dog plasma. Maximal release of kinin was achieved after 4 min of incubation. The kinin generating capacity of the enzyme was studied at different concentrations of kininogen. A maximum kinin release at 11.2 mug bradykinin per mg enzyme per minute was found.


Taste acuity of the human palate. I. Studies with electrogustometry and taste solutions on young adults. The purposes of the study were to determine whether or not taste perception was present in the area which would have been covered by the base plate of a full upper denture and, if taste perception was present there, to compare its strength to that of the remainder of the soft palate and of the apex and base of the tongue. The taste acuity of 32 dental students was measured at the apex and base of the tongue and on the hard and soft palate using two methods, an electric current and sweet, salty, sour and bitter test solutions, the latter in order to determine whether or not there exist differences in the perception of the different taste modalities in these areas. No taste perception could be demonstrated on the hard palate except in the region close to the border between the hard and soft palate, where the threshold values were very high compared with those for the soft palate immediately behind this border and for the tongue. The inter-individual range of the threshold values for the soft palate was very large. Further studies on the taste acuity of the human palate and its role in the total perception of taste are indicated.


Aspiration in local anesthesis. Comparison between disposable self-aspirating and usual syringes. The positive aspirations obtained with a self-aspirating syringe (Astra, Sweden) were compared with those obtained when aspiration  was performed manually (Uniject syringe, Hoechst, West Germany). The subjects were 1186 army recruits, to whom 2348 injections of local anesthetic were given in connection with dental treatment. When aspiration was performed manually, the results were positive in 4.7% of the cases; with the self-aspirating syringe, they were positive in 1.1% of the cases. The total frequency of positive aspirations was significantly higher (P less than 0.001) with the manual aspiration  technique than with the self-aspirating syringe was due to the fact that the value did not include aspiration occurring when the injection needle ruptured small blood vessels.


Amoeboid movement configuration in tumour cells of bone marrow smears from patients with leukaemia. Incidence and significance. The incidence of amoeboid movement configuration (AMC), a cell shape suggestive of cell locomotion at the moment of fixation, has been studied in the tumour cells of bone marrow smears from leukaemia patients at the time of diagnosis. The groups of patients with CML (n = 8), ALL (n = 5) and CLL (n = 9) were small, and the incidences of AMC were close to those found in the corresponding cell lines from healthy probands. In 39 patients with AML, the incidence of AMC was higher than in the other cell lines investigated. A positive skew distribution of AMC values and a positive significant correlation between incidence of AMC were found at the time of diagnosis and subsequent survival of the patients with AML, in spite of differences in treatment. It is suggested that this positive correlation may be due to an immune reaction of the patients against their tumour cells.


Chronic myelomonocytic leukemia: an ultrastructural study by transmission and scanning electron microscopy. The hematologic findings in three cases of chronic myelomonocytic leukemia are presented, with results of ultrastructural studies by transmission and scanning electron microscopy on two of the cases. In the peripheral blood there was a dual, non-lymphocytic, markedly increased population of granulocytes and monocytes. The granulocytes showed marked nuclear abnormality and nuclear cytoplasmic organelle asynchrony. In the marrow the majority of the cells appeared granulocytic but atypical forms and intermediate difficult to distinguish from monocyte precursors were evident by electron microscopy. The ultrastructural findings lend some support to the concept that the neoplastic granulocytes and monocytes having a common precursor.


Esterase activity in erythroleukemia.

Esterase activity in erythroleukemia. Specific esterase activity, a property generally ascribed to cells of granulocytic origin, was found in abnormal erythroid precursors obtained from the bone marrows of six patients with untreated erythroleukemia. These erythroblasts also showed nonspecific esterase activity. Neither specific nor nonspecific esterase activity was detected in erythroid precursors obtained from the bone marrows of ten presumed normal individuals. The implications of finding specific esterase activity in the erythroblasts of erythroleukemia are discussed.


Periodic acid-schiff-positive megaloblasts in pernicious anemia. Periodic acid-Schiff-positive material representing glycogen was found in bone marrow megaloblasts at all stages of maturation from 11 patients with severe untreated pernicious anemia. This accumulation of glycogen in megaloblasts, which are known to have disordered biosynthesis of DNA, RNA, and histones, suggests that carbohydrate metabolism may also be abnormal in vitamin B12 deficiency, perhaps as a result of an abnormality in the enzyme amylophosphorylase.


Renal failure secondary to leukemic infiltration of the kidneys. Leukemic infiltration of the kidneys is a very rare cause of renal failure. A woman with acute lymphoblastic leukemia presented with nonliguric renal failure and was found to have massively enlarged kidneys. The size of the kidneys was dramatically reduced through the combined effects of local radiation therapy and systemic chemotherapy. Because this rapid shrinkage of the kidneys was associated with improvement in renal function, the uremia was ascribed to leukemic infiltration. As a consequence of rapid tumor lysis in the presence of renal failure, marked hyperphosphatemia and hypocalcemia developed. The literature experience with renal failure secondary to leukemic infiltration of the kidneys is reviewed.


Management of cases with upper incisors missing. A problem often confronting the orthodontist is that of missing upper incisors. In evaluation of the individual case, the dicision as to space closure or space regaining and eventual prosthetic reconstruction can be perplexing. Various diagnostic criteria, such as skeletal relation, arch-length analysis, inclination of teeth, and dental esthetics, must be evaluated. On the basis of this diagnostic information, treatment alternative is chosen to correct the malocclusion. The solution may be found in maintaining space, necessitating postorthodontic prosthetic replacement, or closing space and thus avoiding the need for artificial teeth. Four cases are shown to illustrate different approaches to the treatment of patients with upper incisors missing. Other solutions are possible anc correct. Each case must be weighed on its own merits.


Craniofacial templates for orthodontic case analysis. 1. Age-, sex-, and growth-type-specific craniofacial templates represent a practical approach to orthodontic case analyses and craniofacial growth. 2. The Burlington Growth Centre Cephalometric Analysis is a practical adjunct to treatment planning. 3. This cephalometric analysis, which combines many analyses, is an assessment of the relative proportions of the face in length, width, and height (static analysis) and an estimation of the future changes (dynamic analysis). 4. As an aid in diagnosis, the template and/or analysis in conjunction with a cephalogram, with provide information pertaining to (q) cranial base length angle, (b) upper and lower face height and maxillary and mandibular height, (c) size and proportions of the facial bones, both anteroposteriorly and in width, (d) denture relationship, both anteroposteriorly and in width, and (e) expected general growth changes.


Prediction of abnormal growth in class III malocclusions. Four significant factors have been identified in the lateral cephalometric head film which would indicate the likelihood of the patient growing in an abnormal Class III manner. The normal person grows approximately the same amount from nasion to nasion as he does on the corpus axis of the mandible. The abnormal Class III syndrome grows greater increments on the mandible than at the cranial base. For the purpose of determining the accuracy of computer prediction of abnormal growth, fourteen skeletal Class III cases were selected from the files of the Hokkaido University Orthodontic Department. A significant relationship was shown between abnormal growth and the sum of the standard deviation from the normal of the four cephalometric "predictor measurements." These data would give the clinician insight as to which patients might require early orthopedic treatment (chin cup), conventional orthodontic treatment, or surgical orthodontic correction after growth is complete. This is the first published demonstration of computerized cephalometric methods showing the ability to distinguish between normal and abnormal growth in a particular patient type. It is hoped that, through the comparison of thousands of predictions with actual data, more recognizable abnormal growth patterns will appear in the future.


Conceptual orthodontics.

Conceptual orthodontics.


President's page: the responsibility of the society to the individual member.


AAO membership participation in reference committee hearings.


Still more on third molar enucleation (conclusion)


A new generation of anaesthetic ventilators. The Pneupac and Penlon A-P. A new range of ventilators which can be used during anaesthesia for infants, children and adults is described. The ventilators work on the moving-part fluid logic principle and are simple, inexpensive and robust; the patient valve can be autoclaved at standard temperatures (140 degrees C). There are facilities for providing PEEP, attachment of a scavenging system and for relief of over-pressure. The unit is 'fail-safe'. The ventilators, being constant flow generators, have a high specification and equal the performance of other machines which are five times the cost. The weight and size are such that servicing can be provided on a replacement exchange basis through the post.


Animal model: feline acute lymphoblastic leukemia and aplastic anemia.


The Bain circuit. Prevention of anaesthetic mixture dilution when using mechanical ventilators delivering non-anaesthetic gases. Experiments using a lung performance analyser demonstrate that if a 1 m length of corrugated 22 mm diameter anaesthetic breathing how (volume 530 ml) is interposed between a lung ventilator delivering air, and the Penlon  Bain-type co-axial anaesthetic circuit and valve (volume 660 ml), air-dilution of the respired gas mixture is effectively prevented under conditions likely to be used in clinical practice.


An adaptor for coaxial circuits.

An adaptor for coaxial circuits. An adaptor for the conversion of a standard bag mount for coaxial circuits is described.


Pathogenesis of central nervous system infiltration in acute leukemia. The distribution pattern of leukemic infiltrates was studied in 31 cases of acute leukemia with CNS involvement. Dura mater involvement was found in 93% (29/31) of the cases; arachnoid, 71% (22/31); perivascular cuffing, 37% (17/31); parenchymatous, 16% (5/31). Dura matter infiltrates were the sole manifestation in nine cases; Infiltration of the arachnoid in the absence of dural infiltration was rare (9%). The anatomic evidence supports the concept that leukemic cells infiltrate by way of perivenous adventitial tissue connecting the dura mater and subarachnoid space. It is likely that this pathway leads directly from the bones of the skull into the brain parenchyma.


Creatine kinase and lactate dehydrogenase in type 2 glycogenosis (Pompe disease). At least three varieties of type 2 glycogenosis (Pompe disease) have been described, the most severe of which is an infantile form. The relationship between clinical manifestations, glycogen accumulation, and tissue damage has not been established. Serum levels of creatine kinase (CK [EC 2.7.3.2 adenosine triphosphate:creatine phosphotransferase]) lactate dehydrogenase (LDH [EC 1.1.1.27 L-lactate:NAD oxidoreductase]) and their isoenzyme fractions were used to identify and monitor myocardial damage in this study of an infant with type 2 glycogenosis diagnosed by light microscopy and tissue enzyme assay.


Myofibroblasts in parosteal osteogenic sarcoma.


Determinants of human water contact patterns in urban Puerto Rico with special reference to schistosomiasis.


Giant cell pneumonia complicating acute lymphoblastic leukemia in remission.


Recent advances in the diagnosis and in the prevention of rheumatic fever.


Evaluation of cellular mediated immunity in a normal adult population.


Influenza. Treatment and prevention.

Influenza. Treatment and prevention.


Heroin overdose on the rise again? (toxicology of morphine).


Management of long segment esophageal atresia.


Membership.

Membership.


Ischaemic heart disease and hypertension.


More news from the faculty.

More news from the faculty.


Restoration of fractured incisors with an ultra-violet light-polymerised composite resin. A clinical study.


Congenital absence of major salivary glands.


The board report.

The board report.


A suggested method of bleaching tetracycline-stained vital teeth.


Antibiotic sensitivity of oral alpha-haemolytic streptococcus from children with congenital or acquired cardiac disease. A prolonged survey.


Diabetes.

Diabetes.


Report of the Representative Board to the Annual General Meeting of Members, 1977.


Matching therapy and patients: the cafeteria plan.


An attempt at criterion-oriented validation of an alcoholism questionnaire in general practice.


The court-probated alcoholic and outpatient treatment attrition.


Alcoholism in Italy: an outline highlighting some special features.


Effects of deprivation and pre-loading on the experimental consumption of tea by alcoholics and social drinkers.


A speech deficit syndrome associated with addictive drug use.


Cannabis use amongst British university students: II. Patterns of use and attitudes to use.


Factors associated with undergraduate marijuana use in Cork.


Perceptions of marijuana and its effects: a comparision of users and nonusers.


An evaluation of a therapeutic community for former drug users.


A medicine return campaign.

A medicine return campaign.


Cytotoxic antibody in acute myeloblastic leukaemia during immunotherapy: lack of tumour specificity. Cytotoxic antibodies to antigens specific for leukaemic myeloblasts have been sought in the serum of patients with acute myeloblastic leukaemia treated by immunotherapy with irradiated allogeneic myeloblasts and BCG. Assays of complement- and K-cell-mediated activity were used. Cytotoxicity to allogeneic myeloblasts was detected in both assays. When sera from 15 patients, taken at various times during immunotherapy, were systematically tested against a panel of 5 myeloblasts, the following patterns emerged: 1. No antibody was cytotoxic against all myeloblasts of the panel in either the K-cell or complement-dependent assay. However, all myeloblasts of the panel were lysed by a number of sera. 2. Cytotoxic antibody was detected as often against a panel of lymphocytes from healthy donors as against the panel of allogeneic myeloblasts. 3. Fresh and cryopreserved myeloblasts were equally susceptible to lysis in both assays. 4. Experiments failed to demonstrate any deterioration of cytotoxic antibody on storage. 5. The number of K-cell-revealed cytotoxic antisera increased with length of immunotherapy. This pattern was not apparent for antibodies revealed by complement. 6. No instance of cytotoxicity in either assay was seen when serum was tested against 12 autologous myeloblasts. It is considered that cytotoxic antibody detected with allogeneic myeloblasts is probably directed against HLA antigens common to immunizing and test target myeloblasts and target lymphocytes.


Early central nervous system involvement in adults with acute non-myelogenous leukaemia. Of 47 consecutive patients aged 15-60 years with acute non-myelogenous leukaemia (ANML) (40 acute lymphoblastic leukaemia (ALL); 5 acute Burkitt-like leukaemia (ABLL), 2 acute undifferentiated leukaemia (AUL) treated with a standard chemotherapy protocol (OPAL), 31 achieved complete remission (28/40(70%) of patients with ALL). CNS leukaemia occurred in 4/16 non-remitters, and in 6 patients who achieved complete remission (CR). CNS leukaemia occurred in all 5 patients with acute Burkitt-like leukaemia. 4/28 patients with ALL achieving CR had evidence of CSF involvement on cytocentrifuge examination shortly after CR. The apparent risk of early CNS disease suggests that prophylactic CNS therapy should be given early in the treatment of acute non-myelogenous leukaemia.


Biochemical abnormalities in chronic erythraemic myelosis.


Bone marrow culture studies in refractory cytopenia and 'smouldering leukaemia'. As an adjunct to conventional haematological and cytogenetic data, 22 cases of refractory cytopenia, and five with chronic myelomonocytic leukaemia, (CMML) were studied by bone marrow culture. Cultures from II such patients without an excess of marrow myeloblasts usually showed low, or undetectable, numbers of cells capable of giving rise to colonies of granulocytes and/or macrophages (CFUc) but near-normal numbers of cluster-forming cells and cells capable of forming erythroid colonies (CFUE). Those with similar blood pictures, but in whom the marrow contained a slight excess of myeloblasts (II cases), showed a more profound defect in growth patterns: low or undetectable numbers of CFUC, clusters and CFUE, results similar to those found in acute myeloblastic leukaemia, into which three of this group evolved. The patients with CMML gave comparatively normal CFUC, cluster and CFUE growth patterns.


The early detection of remission in acute myelogenous leukaemia by in vitro cultures. Twenty-eight cases of acute myeloid leukaemia without normal myeloid colony growth in vitro were serially cultured by an in vitro agar culture method during remission induction therapy. Colony formation frequently returned before morphological evidence of remission. Without early return of colony formation drug induced aplasia was prolonged and fatal. Analysis of the pattern of return of in vitro colony forming cells may be of value in designing the chemotherapy schedule.


Human deoxycytidine kinase. Purification and characterization of the cytoplasmic and mitochondrial isozymes derived from blast cells of acute myelocytic leukemia patients. A procedure for purifying human cytoplasmic and mitochondrial deoxycytidine kinase (NTP:deoxycytidine 5'-phosphotransferase, EC 2.7.1.74) was developed. Both purified isozymes have a similar molecular weight, activation energy and catalyze the reaction by a sequential mechanism. These two isozymes differ with respect to their substrate specificities. With cytoplasmic deoxycytidine kinase, ATP, GTP and TTP have the highest reaction velocity. Pyrimidine nucleoside triphosphates have higher affinity but lower V than purine nucleoside triphosphates. Cytidine and arabinosylcytidine can serve as substrates. With mitochondrial isozyme only ATP gives the highest reaction velocity. ATP and dATP have the same Km but different V values. Besides deoxycytidine, also deoxythymidine but not cytidine or arabinosylcytidine can serve as substrates. There are also differences between these two isozymes with respect to their sensitivity to inhibition. For cytoplasmic enzyme, Br5dCyd and Iodo5dCyd are not inhibitory. Both dCTP and UTP are competitive inhibitors (Ki 0.25 and 0.5 micronM, respectively) with respect to ATP. For mitochondrial isozyme both Br5dCyd and Iodo5dCyd are inhibitory and dCTP and TTP are competitive inhibitors (Ki 2 and 10 micronM, respectively) with respect to ATP.


Characteristics of blast crisis in chronic granulocytic leukemia. The terminal phase of most patients with Ph1-positive chronic granulocytic leukemia (i.e., blast crisis) resembles acute leukemia. The clinical and hematologic features of blast crisis in 73 patients with chronic granulocytic leukemia have been reviewed. Two major morphological subgroups, lymphoblastic and myeloblastic, were identified. The lymphoblastic group in general had more profound thrombocytopenia and a greater number of blasts, while the myeloblastic group had more severa anemia. Extramedullary leukemia was documented in 27 patients. In 12 patients extramedullary leukemia preceded or occurred simultaneously with blast crisis in the bone marrow and peripheral blood. On the basis of this study we present hematologic criteria for the diagnosis of blast crisis and emphasize the importance of extramedullary leukemia in heralding the onset of blast crisis.


Occlusal film for lateral jaws.

Occlusal film for lateral jaws.


Seek support for nutrition policy.

Seek support for nutrition policy.


Difficulties in leukaemia diagnosis.

Difficulties in leukaemia diagnosis.


Anthracycline cardiotoxicity and acute myelogenous leukaemia.


Recurrence of Gilles de la Tourette syndrome.


Syntactic and semantic correlates of verbal tics in Gilles de la Tourette's syndrome: a quantitative case study.


Chronic myelogenous leukemia simulating chronic granulomatous disease. A 5-year illness of a child, characterized by recurrent bacterial infections and abnormal results of nitroblue tetrazolium dye reduction tests, was suggestive of chronic granulomatous disease but the illness terminated in overt myeloid leukemia. During this progression studies of leukocyte structure and metabolic activity revealed abnormalities that suggested the existence of a "preleukemic" state.


Granulocytic sarcoma of the brain.

Granulocytic sarcoma of the brain. An unusual case of granulocytic sarcoma (chloroma) of the parenchyma of the brain occurring in a patient with acute myelocytic leukemia in remission is described and the literature reviewed. The patient presented with an intracranial mass without clinical evidence of meningeal involvement. The value of 99mTc scan in CNS leukemia is shown.


Prognotic significance of pretreatment proliferative activity in adult acute leukemia. A statistical analysis of the prognostic significance of eight pretreatment variables was undertaken for 71 previously untreated adult patients with acute leukemia seen at M.D. Anderson Hospital over a 5 1/2-year period. None of the patients had received any prior therapy. Nearly all of the patients (68 of the 71) were treated with 4- or 5-day courses of arabinosyl-cytosine alone or in combination with cyclophosphamide, vincristine (oncovin) and prednisone (COAP). The pretreatment variables studied were age at diagnosis, the percent labeling index of the bone marrow leukemic cells, diagnosis, the highest temperature prior to start of treatment, the marrow clot section cellularity and smear differential percent of blasts, percent absolute marrow leukemic cell infiltrate and absolute number of blasts X 10(3)/mm3 in the peripheral blood. Fifty-one patients had acute myeloblastic leukemia (AML) and 20 patients had acute lymphoblastic leukemia (ALL). Using a statistical regression model approach, the only variables found to be of significant prognostic importance with respect to the probability of complete remission for AML patients were the pretreatment percent labeling index, the age of the patient and the highest temperature prior to start of treatment. Unlike AML, the initial percent labeling index did not appear to be of prognostic significance for ALL patients. AML patients with high labeling indices (larger than or equal to 9%) and young patients in general (especially those less than 40 years old) had the best remission rates. With respect to the length of complete remission and survival for all patients, the only important variables were the pretreatment percent labeling index and the age of the patient, respectively. Once in complete remission, an initially high labeling index was an unfavorable sign with respect to length of remission, regardless of the patient's diagnosis. The results of this study are supportive of studies in experimental systems demonstrating the importance of cytokinetic factors in the administration of chemotherapy and suggest that such factors may be of clinical importance in selecting approaches to therapy.


Leukocytic fibrinolysis in myelomonocytic leukemia. A case of myelomonocytic leukemia is described in which an increase in primary fibrinolytic activity produced a severe hemorrhagic diathesis. The leukemic cells were demonstrated to be the source of the fibrinolytic activity. Utilizing a fibrin coated slide technique, the intact leukemic cells were shown to release their fibrinolytic activity and to induce local lysis. Intact leukocytes from normal subjects and other patients with acute leukemia of varied cell types were unable to release fibrinolytic activity although in some of the leukemic preparations, increased fibrinolytic activity was demonstrated after in vitro disruption of the cells.


Early deaths in acute myelogenous leukemia. In a series of 84 patients with acute myelogenous leukemia, 24 died within 6 weeks of starting treatment. Twenty of the 24 patients had failed to achieve remission at the time of death. Death was due to infection in 20 patients and in 17 of these to septicemia; but whereas severe local infection with septicemia accounted for 12 deaths, only five patients died of septicemia without local infection. Bleeding was the direct cause of death in only four patients and an associated terminal event in another three; of these four patients three had disseminated intravascular coagulopathy. Surprisingly, in this group of patients age and overall clinical status at the time of admission were of no prognostic value in the first 6-week period. The importance of drug resistent disease associated with intractable local infection as a major cause of early death is emphasized.


Cytogenetics of juvenile type chronic granulocytic leukemia. Cytogenetic examination of bone marrow cells from three patients with juvenile chronic granulocytic leukemia (CGL) showed 46,XX,3p-,11p+ ,t(11p:3p) in one case, 45XY,-E in another, and 45X(X),-C/47,XX,+G in the third. The case with the translocated chromosome originally presented like an acute lymphocytic leukemia (ALL). TAn overt clinical picture of juvenile CGL emerged two and a half years later. Serial study of this case revealed no cytogenetic abnormalities until two years after the diagnosis of ALL, when the translocated chromosome was first observed. Unlike the Ph1 chromosome in adult type CGL, chromosomal abnormalities in juvenile CGL lack specificity, resembling ALL in this respect.


Ultrastructure of osteoblastoma.

Ultrastructure of osteoblastoma. The ultrastructure of three cases of osteoblastoma is described. The osteoblasts resemble normal osteoblasts with a few exceptions: irregular, indented nuclei, and occasional mitochondria with curved cristae and electron-lucent areas. The osteocytes and osteoclasts basically resemble their normal counterparts. There are also osteoprogenitor cells in different stages of maturation, some containing glycogen. The ultrastructure of an additional case histologically classified as aggressive osteoblastoma is described. It is essentially similar to the previous three cases of typical osteoblastoma. The only exception is the presence of osteoblasts with electron-lucent nuclei and less prominent organelles than the typical osteoblastoma cells have markedly indented and multilobed nuclei, dilated rough endoplasmic reticulum and lipid droplets. However, these differences from osteoblastoma cells are not pathognomonic. The final diagnosis of osteoblastic tumors rests at the light microscopy level.


Aneurysmal bone cysts: a clinicopathological study of 105 cases. A clinicopathological review of 105 cases of aneurysmal bone cyst is reported. Age and sex distribution and localization were in agreement with two previously reported large series. Recurrence occurred in 30.5% of all the cases and in 34.2% of those treated by curettage. Proved incompleteness of surgical removal was an important factor in recurrence (12 out of 17 cases or 70.6%). The recurrence rate was significantly (P2 less than 0.01) higher in cases with a mitotic index of seven or more per 50 fields (X 750) than in those with a lower mitotic index. In relation to the recurrence rate, no statistically significant differences were found between the age groups less than or equal to 15 and greater than 15 years, between the combination age and lesion size, or between four localization groups. The cyst wall and the septa consist of a superficial layer of cellular fibroblastic and histiocytic tissue in which multinuclear giant cells are present, covering a deeper situated zone of less cellular fibrous tissue. This typical layered architecture was found at one or more places in 93 (88.6%) out of 105 cases. However, layered architecture may also be found in cases of teleangiectatic osteosarcoma. It is suggested that the group with a high risk of recurrence be treated more radically, i.e., with cryosurgery.


Cardiac arrest due to hyperkalemia following therapy for acute lymphoblastic leukemia. A patient with acute lymphoblastic leukemia with a large tumor burden is presented. Following successful chemotherapy, the patient experienced a cardiac arrest presumably due to hyperkalemia in association with hyperuricemia. The implication of these findings for patients with responsive hematological malignancies is discussed.


Utilization of long-chain free fatty acids and glucose by human leukemic blast cells. We have studied the utilization of free fatty acid and glucose by human leukemic blast cells. Palmitate was both incorporated into complex cellular lipids, primarily phospholipids and triglycerides, and oxidized to CO2. The predominant phospholipid synthesized was phosphatidylcholine. Only a small proportion of the incoming fatty acid was modified structurally before incorporation into lipid esters. After incubation with [1-14 C]palmitate, 91% of the radioactivity recovered in cell lipids remained in fatty acids containing 16 carbon atoms. Studies with labeled glucose revealed little de novo synthesis of fatty acid, and the majority of the radioactivity from glucose was located in the water-soluble fraction after saponification of the esters. We conclude that the free fatty acids contained in the extracellular fluid provide much of the fatty acid for required cellular lipid synthesis in human leukemic blast cells. Since there is little elongation of incoming palmitate before incorporation into cellular lipids, it may be possible to alter the fatty acid composition of membrane phospholipids by changing the proportion of the various free fatty acids available to the leukemic cells.


External surface membrane proteins in normal and neoplastic murine erythroid cells. The development pattern of one class of plasma membrane proteins, the external surface proteins, was examined in neoplastic and nonneoplastic differentiating murine erythroid cells. Neoplastic erythroid precusor cells were obtained from spleens of CD-1 mice after infection with Friend erythroleukemia virus while the nonneoplastic ellls were obtained from spleens of mice with phenylhydrazine-stimulated erythroid hyperplasia. Erythroid precursors at different stages of development were isolated from these erythroid cell populations by sedimentation at unit gravity. The surface proteins were labeled by lactoperoxidase-catalyzed iodination, solubilized in sodium dodecyl sulfate, and separated by sodium dodecyl sulfate gradient gel electrophoresis. Multiple labeled bands were found at all stages of neoplastic and nonneoplastic erythroid differentiation examined. The pattern of external membrane proteins labeled in nonneoplastic erythrocytes and in reticulocytes from peripheral blood were qualitatively similar and not altered by infection with Friend virus. The nucleated precursor cells from noninfected mice exhibited distinct differences from erythrocytes, and with increaseing differentiation an evolutionary pattern of several minor proteins was seen. Clear-cut differences in lactoperoxidast-reactive proteins were also observed between neoplastic and nonneoplastic precursors. The most marked differences were observed between the most immature cells. The youngest neoplastic cells from CD-1 mice possessed a protein with a molecular weight of 8000 not seen in normal erythroid cells. Additionally, there was an absence of a normally occurring protein with a molecular weight of 13,000 and increased amounts of a protein with a molecular weight of 140,000. With increasing maturation of the neoplastic cells, labeling of the protein with a molecular weight of 8,000 decreased while the protein with a molecular weight of 13,000 became apparent, so that a labeling pattern similar to that of nonneoplastic cells was obtained. These studies deomnstrate both distinct alterations of lactoperoxidase-reactive surface membrane proteins in nonneoplastic erythroid cells druring cell maturation in neoplastic erythroid cells as compared with nonneoplastic erythroid cells at similar stages of development.


Streptococcus mutans serotypes in young schoolchildren.


Inhibition of adherence of Streptococcus mutans to glass surfaces.


The histopathology of artificial lesions created in vitro in relation to unfilled and filled cavities.


Evaluation of a combination of self-administered fluoride procedures for control of dental caries in a non-fluoride area: findings after 2 years.


Dislocations and dissolution in apatites: theoretical considerations.


Studies on medically important flies in Thailand II. Record of four species of Lucilia Robineau-Desvoidy (Diptera: Calliphoridae). As for the genus Lucilia, only one species, Lucilia papuensis Macquart, has been recorded by R. Senior-White el al. in Thailand. During our survey in Thailand in 1975, we found newly 3 more species belonging to the genus Lucilia. These are L. cuprina (Wiedemann), L. porphyrina (Walker) and L. sinensis Aubertin. The female of L. sinensis has never been reported. Therefore, the female genitalia of L. sinensis are illustrated in this paper and compared with those of L. papuensis. The male genitalia of L. sinensis and L. papuensis are also illustrated in this paper.


An electron microscopic observation on cells found in bone resorption area incident to experimental tooth movement. For the purpose of investigating many of the cells in the bone resorption area incident to experimental tooth movement and characterizing the role of these cells for the periodontal tissue resorption at the ultrastructural level, orthodontic force was applied to 24 male rats. Orthodontic elastics were inserted into the interproximal space of the upper first and second molars. The mesial side of the interradicular septum of the second molar was observed. The electron micrsocopic findings were as follows: 1. Cell cohorts were found in the undermining bone resorption area. They are mainly composed of fibroblasts, endothelial cells, undifferentiated cells, macrophages and several kinds of osteoclasts. 2. Four different kinds of osteoclasts could be recognized from the morphological features: a) small osteoclasts situated apart from the bone surface, b) large osteoclasts rich in rough ER, c) classic large osteoclasts and d) degenerating osteoclasts. 3. Two different types of undifferentiated cells were observed in these area. One was a spindle-shaped bright cell rich in rough ER and the other was a round-shaped dark cell with numerous mitochondria and free ribosomes. 4. Macrophages showing phagocytosis were also found in the bone resorption area.


Studies on the retrograde pancreatography in autopsy specimens. In order to study the normal and aged anatomical structure of the duct system of human pancreas, retrograde pancreatography was performed. Pancreas from 33 cadavers of non-pancreatic disease, aged from 0 to 81 years, was examined. Silicone rubber was injected through the canal of Wirsung, radiographs were taken, and microstereoscopic observation was done after clearing in methyl salicylate. The main duct tapered gradually toward the tail, branching off about 56 second term ducts at a regular interval. The eighth term branch became the centroacinar ductules in the peripheral region, and the fourth and fifth term branch did it in the proximal region. In aged cases, prominently over 60 years, the main duct became large in caliber and showed irregular dilatation and narrowing like beads. The second term ducts were visualized as irregular patterns. The figure of distortions like a corkscrew was also seen in smaller ductules of the aged cases over 50 years. The histological findings of these sites were not the pancreatitic lesions but only the increase of fibrous tissues and decrease of a cellular component in the ductal wall itself.


Studies on the microvasculature of human myocardium. The microvasculature of human myocardium was examined stereoscopically after the injection of Silicone rubber. Material were 40 normal hearts, three of infants, one of child, and 36 of adults, ranging in age from 27 to 79 years. Three types of arteries, subepicardial, branching, and straight type arteries, were confirmed. The microvascular pattern of left ventricular free wall, the posterior wall of the left ventricle, interventricular septum, right ventricular free wall, papillary muscles, trabeculae carneae, infant heart, and aged heart were also examined. The present study revealed that the inner one-third zone was supplied by the terminal branches of both branching and straight type arteries. In infant heart, the inner zone was wider than that of the adult. In the aged cases, reduction in filling with patchy deficit often appeared in this inner zone. The finding of the aged change was probably caused by the characteristic microvascular pattern, and this suggested that the same anatomical mechanism might commit myocardial infarction.


Endogenous carbon monoxide production in alloxanized rats. The endogenous production of carbon monoxide (Vco) in thirty-three diabetic rats induced by alloxan and in fifteen normal rats was measured by serial determinations of the expired carbon monoxide and of the increase of carbon monoxide in the blood during rebreathing in a closed system. Vco (mean +/- S.E., micronl/250g/hr) in the group of alloxanized rats 24, 48, 72, 96, 120 and over 144 hours after the alloxan injection was 6.2 +/- 2.9, 8.4 +/- 2.1, +/- 1.8, 10.7 +/- 3.5, 16.4 +/- 2.0 and 16.5 +/- 2.2, respectively, whereas it was 5.9 +/- 0.4 for the control. This indicates that the alloxanized group maintaining a high blood sugar level for over 120 hours has a three-fold higher Vco than the control.


Structure and hardness of four types of amalgam. Three non-gamma2 and one conventional amalgams were compared for their structure and hardness. The Ag-Cu dispersants hardened the amalgam by generating hard Cu-Sn halos and diminishing the gamma2 phase. The Ag-Sn-Cu-In single composition alloy produced the hardest amalgam by its high hardness and the Cu-Sn reaction phase scattered as minute granules.


Mechanical behavior of tooth, periodontal membrane, and mandibular bone by the finite element method. Simulation of the human tooth, periodontal membrane, and mandibular bone was attempted basing on the anatomical form and dimension, and the experimental data of each component were examined by the two-dimensional finite element method. Following problems were investigated: (1) Which of two factors, elastic modulus or Poisson's rate, in periodontal membrane played an important role for supporting the tooth, and (2) Characteristics of tooth and alveolar bone displacement, and stress distribution in periodontal membrane and mandibular bone were investigated under a definite condition. It is clarified that Poisson's ratio plays a much important role than the elastic modulus and this method is more suitable for simulating the model equivalent to human body and for examining the internal stress and it's displacement than the strain gauge and photoelastic method.


A scanning electron microscopic study on the differences between newly erupted teeth and old teeth with reference to fissure enamel surfaces and contents. Scanning electron microscopy of the fissure enamel surfaces of newly erupted permanent teeth and old sound teeth long-standing against caries demonstrated two distinct features; prismatic enamel and prismless enamel. Prismatic enamel was commonly found on the walls of fissures of newly erupted teeth and rarely found on both sides of fissures of old teeth. Prismless enamel was usually found on both sides of fissures of old teeth. Various types of calcified contents were almost confined on the prismless enamel surfaces of the occlusal orifice of fissures of old teeth, while organic materials and bacterial contents were found on the prismatic enamel surfaces of newly erupted teeth.


The protective effect of propranolol on ischemic myocardium: an electron microscopic study. The protective effect of propranolol on ischemic myocardium was studied experimentally and clinically by electron microscope. In an animal experiment, ischemic changes were produced in the posterior papillary muscle of the rabbit following 3, 15, 30 minutes of occlusion of the circumflex coronary artery. Propranolol (0.25 mg/kg) was injected into the left atrial cavity before occlusion of the artery. The posterior papillary muscle was excised and examined by electron microscope. In clinical experience, propranolol (20 microng/kg) was given intravenously to 6 patients who underwent open heart surgery. Transmural left ventricular myocardial biopsy was performed after the anoxic cardic arrest and the material, particularly the subendocardium, was examined by electron microscope. It was shown that propranolol was effective, both in the experiment and in the clinical experience, in preserving ischemic myocardium. The possible mechanisms through which propranolol might act were considered to be (1) indirect effect of altered oxygen supply vs. demand, effect by reducing heart rate and reducing cardiac output due to the drug's function as a beta blocker, (2) direct cellular effect, i.e., reducing myocardial substrate metabolism along with stabilization of cellular structure, and (3) increase collateral circulation to the subendocardium.


Risks to the newborn from the routines in the delivery room.


Student opinions concerning use of an evaluation form as a teaching aid.


MBO as a faculty evaluation system.

MBO as a faculty evaluation system.


Guidelines: hepatitis patients and dental hygiene practice.


A model for teaching the components of the family in dental care.


Values clarification and role-playing in dental hygiene education.


A late clonal evolution of a human leukemic line: sequential cytogenetic studies.


Responsibility the key work in coping with society's new challenges.


Federal income tax returns by dentists.

Federal income tax returns by dentists.


The estimation of age of skeletal remains from the colour of roots of teeth.


Preventive dentistry: its role in periodontal disease.


Occlusal adjustment in orthognathic surgery: the team approach.


Report of a case: removal of an antral dentigerous cyst via a modified Caldwell-Luc.


Use of the vitalometer with rubber gloves.


Report of a case: caries under an occlusal sealant.


The Canadian Dental Aptitude Test.

The Canadian Dental Aptitude Test.


Is dry socket preventable?

Is dry socket preventable?


ADA adopts position statement on dental laboratory industry.


'Dentists should promote new prophylaxis concepts'.


Testing hypnotic susceptibility: 30-second chairside technic.


Specialist's prestige: based on level of achievement.


Easy duplication of radiographs in seconds.


The 'biggest show in town': thoughts on the ADA meeting.


PreTest on oral medicine.

PreTest on oral medicine.


Thorough preparations help insure trouble-free travel.


'Atmosphere of spaciousness' helps reduce patient anxiety.


New office was once horse barn.

New office was once horse barn.


Planning an in-office metal ceramics laboratory.


Dear Mr. FTC Commissioner, Senator and Representative:.


The other side of the coin.

The other side of the coin.


Dear Dr. Olsen:.

Dear Dr. Olsen:.


Dear editor:.

Dear editor:.


Guidelines for continuing dental education.


Illinois State Dental Society manual on dental prepayment 1977.


Illegal dentistry. What can you do? Here's first answer.


Dental education in relation to the needs of the South African community. The dental needs of a heterogeneous South African community are not being fully met because the majority of the already deficient dentist population is in private practice, mostly in urban areas, where they are rendering services to a small minority of the population who can afford comprehensive dental care. Contrary to public health services in general, public dental services are inadequate in extent and provide a limited range of treatment to some eighty-five per cent of the population. Millions of under-privileged people, particularly in rural areas, are not within range of any professional dental care whatsoever. Organized community preventive programmes and dental health education on a national basis are non-existent. Water fluoridation has not yet become a reality. Realizing the shortcomings in community dental services the Government recently adopted a national dental health policy which is aimed at limiting and preventing dental diseases and also at expanding the public dental service to bring it within reach of all sections of the community. In order to meet the dental needs of the community and also to give momentum to the national dental health policy, the following steps are being taken as far as dental education is concerned: (i) The Department of Health is planning to assist universities to establish departments of community dentistry with the object of promoting extended education in community dentistry at under-graduate and post-graduate level. (ii) Consideration is being given to a scheme whereby dental students will have to do one year compulsory intership. (iii) Additional dental schools are being established to enable more non-White dentists to qualify. (iv) With the extended education in community dentistry it is hoped to draw more dentists into community dental services. (v) Dental therapists are being educated to perform duties such as extractions, simple fillings, prevention and dental health education, under the supervision of dentists, in areas where the shortage of dentists is most crucial.


Changing patterns in dental education in Latin America. The unsatisfactory dental health situation in the majority of the Latin American population, presently not covered by existing dental services, led to a serious questioning of the educational process directed to prepare human resources in dentistry. At the present time, many dental schools in Latin America are trying to find and implement new teaching methods, different curriculum patterns, and even seeking to define new professional and non-professional profiles, in order to meet the tremendous challenge that requires the formation of a different type of dental health personnel capable of introducing definite changes in the way dentistry is conceived and performed in order to cover the needs of a constantly growing population.


Dental education in the developing countries and the role of WHO. The present picture of Dental Manpower in the world is reviewed. The Dentist/Population ratio in 1972 in each of the WHO regions was as follows: African Region 1:96,391, American Region 1:2892, Eastern Mediterranean Region 1:26,188, European Region 1:2948, South East Asia Region 1:81,606, Western Pacific Region 1:4533. There was wide variation of this ratio between individual countries within each region. The present approach to the dental education of all types of dental personnel in the developing countries is described. The activity of WHO in organizing seminars and conference on the needs of the regions in relation to types of dental personnel and their training is discussed. Attention is drawn to the strong recommendation of WHO to plan the dental health manpower training in close conformity with a country's Oral Health needs. The importance of integration of the training programmes for the various categories of dental personnel is stressed.


Histological and histochemical studies of oral cancer. Increasing attempts are now being made to measure and to assess the relative importance of histologic features in oral premalignant and malignant conditions in order to improve the accuracy of diagnosis and prognosis. Though certain individual features, such as DNA content of cell nuclei, or stereological parameters like nuclear : cytoplasmic ration or desmosome density can be very accurately quantified, no single feature can completely characterize the neoplastic process. Multifactorial studies are thus of great importance, even though it is not practicable to measure all the parameters included with the sam accuracy; in such studies retrospective computation of the relative importance of individual parameters is of greater value than arbitarily assigned weights. So far as early prediction of malignant transformation in oral premalignant lesions is concerned, great interest is now being shown in the reactivity of glucose-6-phosphate dehydrogenase in epithelial cells. For predicting the prognosis of patients with established squamous cell carcinoma of the mouth, it is now realized that thenature and intensity of the host immune inflammatory response seen in the connective tissue within the surrounding the tumour and in affected regional lymph nodes, is at least as important as are the features of the tumour cells themselves.


Critical review of biopsy and cytologic examination of oral cancer. The value of cytologic diagnosis has been highly estimated since Papanicolaou introduced cytologic study into various clinical fields as a diagnostic tool. In this paper the causes of errors in diagnosis, particularly the false negative case which occurs more frequently than false positive cases are critically reviewed. Four false negative cases, including one case subsequently diagnosed as positive by a direct imprint smear taken from its biopsy section, are presented in detail and possible causative factors for misinterpretation discussed and summarized, comparing the results with those previously reported by Watanabe et al (1959) and Watanabe (1968). In the 24 cases reviewed in this article false negative diagnoses were made in 12-5 per cent and in summarizing the results with the previous reports they averaged 14-5 per cent. False negative cases could be reduced by careful attention to the elimination of the causative factors which have been described.


Recommended outline for a research protocol. Prepared by a working group of the Commission on Dental Materials, Instruments, Equipment and Therapeutics.


Recommendations in dental mercury hygiene. Prepared by the Commission on Dental Materials, Instruments, Equipment and Therapeutics.


Recommendations for dental radiographic procedures. Prepared by the Commission on Dental Materials, Instruments, Equipment and Therapeutics.


Recommendations on the training and qualifications of public health dentists. Prepared by a working group of the Commission on Public Dental Health Services.


Endocrine function after antineoplastic therapy in 22 children with acute lymphoblastic leukaemia. In 22 children who were in complete remission after acute lymphoblastic leukaemia endocrinological investigations were performed 5-12 weeks after cessation of therapy. The children had received central nervous system irradiation (tele-Co60, 850-1800 rad), and long term, aggressive cytostatic drug therapy during 21 to 36 months. Growth hormone, TSH, thyroxine, LH, FSH, cortisol secretion, and urinary concentrating capacity were found to be normal, with a few exceptions where borderline results were obtained.


Early and late volume changes during erythroid differentiation of cultured Friend leukemic cells. Friend erythroleukemic cells (FLC) can be induced to differentiate in vitro by addition of dimethylsulfoxide (DMSO). We have studied the kinetics of induction by measuring cell volume, volume coefficient of variation and cell doubling time. Two distinct volume changes (early and late) are observed after the addition of the inducing agent. The early change occurs after ten hours and consist of a 10-20% decrease in volume compared to an untreated control population. This shift persists for two days and its magnitude is proportional to both the concentration of DMSO and the number of differentiated cells seen on day 5. FLC lines which induce weakly or not all with DMSO exhibit a reduced or absent early volume shift. Inclusion of a local anaesthetic in the culture prevents the appearance of differentiated cells and also counteracts the early volume shift. The exact time of the early volume change is a function of cell growth rate and appears to be cell cycle related. Synchronized cell populations exposed to DMSO during G2 and S phase undergo one round of mitosis before expression of the volume change whereas cells in G2-M express the change only after a second mitosis. A later, more gradual decrease in volume is observed in those cultures which begin to produce hemoglobin. It occurs after approximately five doubling times and coincides with the first appearance of hemoglobin-containing cells. Volume distribution parameters indicate that only a proportion of the population becomes smaller in size.


Terminal deoxynucleotidyltransferase distribution in neoplastic and hematopoietic cells. In the present study, terminal deoxynucleotidyltransferase was examined in the peripheral blood and (or) bone marrow of 115 children with a variety of neoplastic, hematologic, and other unrelated disorders. Terminal deoxynucleotidyltransferase activity was present at 4.08+/-0.74 U/108 cells in 23 morphologicall normal bone marrow samples from childhood controls. Terminal transferase was present at greater than 23 U/108 nucleated cells and at greater than31 U/108 blasts in the bone marrow of all children with acute lymphoblastic leukemia studied at initial diagnosis and at disease relapse. Terminal deoxynucleotidyltransferase was detectable at low levels, less than 7.5 U/108 cells, in all remission marrow smaples. Bone marrow terminal transferase activity was markedly elevated in all untreated acute lymphoblastic leukemia patients, whereas low levels which were difficult to interpret were present in the peripheral blood samples of two patients at diagnosis and six patients at relapse who had low absolute lymphoblast counts. Because of greater variation in the lymphoblast content of peripheral blood, bone marrow assays are more reliable in detecting disease activity. Marrow terminal deoxynucleotidyltransferase values obtained during the active phase of acute lymphoblastic leukemia were significantly greater than those found in other types of leukemia, bone marrow malignancies, and hematologic disorders. Terminal transferase determinations in blast cells of two patients with leukemic conversion of non-Hodgkin's lymphoma and in tumor cells from one patient with Burkitt's lymphoma were within the control range. These dat further define the usefulness of terminal deoxynucleotidyltrnasferase assay in the differentiation and classication of hematologic malignancies.


The dentist's role in high blood pressure detection. Why dentists.


Immune dysfunction and dental caries: a preliminary report. This study was undertaken in order to correlate the immune status of persons with various types of immune dysfunctions with the incidence of dental caries. Preliminary data on caries experience and the microbial composition of plaque in these individuals are presented. The findings suggest that persons with immunoglobulin dysfunctions have a greater susceptibility to dental caries and have a greater frequency of harboring S mutans than do normal persons.


Virulence of Streptococcus mutans: an antibiotic-suppressed rat model for studies of pathogenesis. This investigation describes a simple and effective method of antibiotic suppression of the total indigenous microbiol flora of rats. Specifically, the results of this study demonstrate that: (1) antibiotics which inhibit microbial growth of oral and fecal cultures from individual rats are effective in suppressing the indigenous flora of 95% of these rats when provided as dietary supplements; (2) S mutans 6715 colonized 95% of the antibiotic-suppressed animals while only 50% of the untreated rat pups yielded S mutans following challenge with a single inoculum of this micro-organism; and (3) significant smooth surface caries developed in S mutans-infected rats within 20 days when provided caries-promoting Diet 305, while noninfected, antibiotic-suppppressed offspring remained essentially caries-free.


Combined effects of sucrose and fluoride on experimental caries and on the associated microbial plaque. In an experimental model, slabs of sound and presoftened bovine enamel were worn in the human mouth for seven days except for periodic removal for in vitro exposure to experimental variables. Supplementation with 3% sucrose for 10 minutes, four times daily for seven days yielded predicted levels of experimental caries. Parallel exposure to 3% sucrose containing 100 ppm fluoride sharply reduced or negated the resultant caries in originally sound enamel, and reversed the simulated pre-experimental caries in most samples of presoftened enamel. Serial layers of test enamel surfaces showed high levels of fluoride accumulated in the originally sound enamel, and even higher levels in the presoftened enamel that had been suppemented with sucrose-fluoride solution. Quantitation of the plaqye microbial flora showed that the fluoride ion exerted no detectable influence. Consistent with the findings in previous studies, some correlation appeared to exist between the degree of experimental caries and that proportion of total plaque that was comprised of S salivarius. S mutans, or lactobacilli.


Sources of variability in rat caries studies: weaning age and diet fed during tooth eruption. A factorial design (2x2) was used to study the caries effect of two diets (starch based versus stock) fed to rat dams and their litters, and also of variations in the weaning age (19 versus 25 days). Higher and reproducible caries scores were obtained in rats which were fed a purified starch-based diet, weaned at 19 days of age, and subsequently given a cariogenic challenge.


Noncollagenous proteins of a rat dentin matrix possessing bone morphogenetic activity. An insoluble preparation of rat dentin matrix was shown to possess bone morphogenetic protein (BMP) activity, i.e. the capacity to induce the formation of catilage and bone when implanted intramuscularly. Since BMP activity was previously attributed to noncollagenous proteins (NCP) of bone and dentin, the nature of NCP of the rat dentin was examined. After treatment of the matrix with purified bacterial collagenase, three NCP were solubilized concomitantly with digestion of the dentin collagen to smaller peptides. The three proteins were separated by anion-exchange chromatography on DEAE-cellulose. Two of the NCP were rich in asparate, glutamate, glycine, serine, and alanine, and thus displayed compositions similar to acidic proteins of other connective tissues. The third NCP was shown by amino acid composition to be the aspartate, serine-rich phosphoprotein, which occurs mostly in a soluble form in rat dentin. This observation supports the view that a portion of dentin phosphotprotein is firmly bound.


The phosphoprotein of rabbit in cisors.

The phosphoprotein of rabbit in cisors. The phosphoprotein of continually erupting rabbit incisors was extracted from decalcified teeth and purified by gel filtration and ion-exchange chromatography. Chemical characterization revealed that its composition was very similar to that of rat incisor and bovine molar phosphoproteins. The presence of similar acidic proteins in the dentin of various mammals is consistent with the suggestion that they are involved in the mineralization process.


Biochemical and morphological studies of rat submandibular gland: III. effects of testosterone treatment on proteins of granule-rickch fraction. Mature adult male rats and castrated and testosterone-treated castrated adult rats were injected with pilocarpine HCl and 3-H-lysine and sacrificed sequentially over an eight-hour time period. Following homogenization and differential centrifugation, three subcellular fractions from each group of animals were analyzed by gel electrophoresis and liquid scintillation. Two proteins in the granule-rich fraction appeared in larger amounts on the densitometric scans and appeared to represent a larger proportion of newly synthesized proteins than the other proteins.


Electromyographic silent periods and jaw motion parameters: quantitative measures of temporomandibular joint dysfunction. The purpose of this research was to compare, in the subjects, the duration of the EMG silent period with jaw motion error. The results indicate that both jaw motion error and silent period duration are large in patients with TMJ-muscle-pain dysfunction, both are small in normal subjects, and both are small in successfully treated patients. There is a statistically significant correlation (r=0.91; P less than 0.01) between the two diagnostic parameters of TMJ-muscle-pain dysfunction.


Age and race as factors in craniofacial growth and development. Large samples of adult American black and white males are being studied to determine the extent to which age and race are important factors in craniofacial mophology and growth. It is shown that a number of dentofaical dimensions continue to change throughout adulthood and that the amount and direction of these changes may be race-specific. Applications in orthodontics and prosthetic dentistry are indicated.


Changes in rat parotid salivary proteins induced by chronic isoproterenol administration. Changes  in the rat parotid gland and its secretion, brought about by chronic isoproterenol administration, were studied. In addition to the expected enlargement, morphological and biochemical analyses of the glands showed evidence of changes in the secretory components. Chromatographic and electrophoretic experiments revealed both qualitative and quantitative changes in the secretory proteins.


Stimulation of bone formation and bone resorption by fluoride in thyroparathyroidectomized rats. In sham-operated and TPTX animals, F treatment did not affect final body weight, or serum Ca and P. In sham-treated rats, serum iPTH was not affected by F treatment. At the periosteum, F increased bone formation rate and bone and matrix apposition rates. At the endosteum, F treatment decreased forming surface, bone formation rate, bone and matrix apposition rates, and osteoid maturation rate; and increased endosteal resorbing surface and medullary area. The above-described F effects on bone were observed in TPTX as well as sham-treated animals. The effect of F treatment to stimulate periosteal matrix apposition was enchanced by TPTX. These results indicate that bone changes seen in animals treated with large amounts of F are not due to increased parathyroid activity.


In vitro study of cellular influence on 45Ca uptake in developing rat enamel. The in vitro method for culture of molar teeth from eight-day-old rats, as reported in this study, appeared to sustain reasonably normal activity in the cells of the enamel organ and pulp through culture periods of four to eight hours. Inhibition of metabolic activity in the explants by addition of 5 mM iodoacetate or 2,4-dinitrophenol to the culture medium, or by heating at 70 C for 10 minutes, did not appear to affect the intensity or pattern of 45Ca uptake in the more advanced, rapidly mineralizing areas of the enamel. Neither did stripping of the enamel organ from the surface of the enamel have a demonstrable effect in those areas. However, metabolic inhibition with 2,4-dinitrophenol, heat killing or stripping of the enamel organ resulted in increased 45Ca uptake in newly formed enamel adjacent to the secreting ameloblasts. It is hypothesized that calcium flux into newly formed enamel matrix is controlled, in part, by movement of the calcium, which diffuses between the ameloblasts toward the enamel surface, away from the enamel through the ameloblasts.


Purification and partial characterization of deoxyribonuclease I from bovine parotid gland. Deoxyribonuclease I has been purified from bovine parotid gland. The purification procedure utilizes an acid extraction of minced parotid gland, salt fractionation, gel filtration, and ion-exchange chromatography. The last step, chromatography on Sulfopropyl-Sephadex, resolves the enzymatic activity into several fractions. The major fraction, designated DNase A, was subjected to further investigation. This enzyme has, as expected, an alkaline pH optimum and an obligate requirement for divalent cations. The presence of calcium chloride protects DNase A from inactivation by proteolytic enzymes. Despite the previously described immunologic dissimilarity, there appears to be a large amount of homology between the parotid and pancreatic DNase's.


In vitro metabolism of 4-androstene-3,17-dione by human submaxillary gland homogenates. Tritiated 4-androstene-3,17-dione was incubated with human submaxillary gland homogenates. In 180-minute incubations, human submaxillary gland converted 4-androstene-3,17-dione predominately to testosterone and to a lesser extent, 5alpha-androstane-3alpha,17beta-diol and androsterone.


Hardening of gold-based alloys.

Hardening of gold-based alloys. The relationships between composition, heat treatment, hardness, and microstructure have been investigated for a number of commercial dental casting alloys and for several series of experimental gold-silver-copper compositions. The hardnesses and typical microstructures found are reported. The results indicate that at least two distinct hardening mechanisms must occur in these alloys. The ternary alloys outside the two-phasr region of the gold-silver-copper system harden by ordering. The commercial alloys and those within the two-phase region may harden in part by ordering, but some other mechanism in required to explain the observed hardening. This mechanism is not due to the observed grain boundary precipitates. It may be associated with the intragranular needlelike structures seen, but reasons exist to question the sufficiency of that structure as an explantation of the hardening.


Research and development contracting at the National Institute of Dental Research. Government contracting for biomedical research and development is a cooperative venture of high public visibility. It must be soundly conceived, openly instituted, and skillfully managed. Because of the cooperative nature of contract activities, it is important for the scientific community to understand the contract mechanism and the concepts upon which its use is based. Therefore, these concepts are described and how this mechanism serves as an aid in accomplishing the mission of the National Institute of Dental Research is discussed.


Relationship of Streptococcus mutans biotypes to dental caries prevalence in Saudi Arabian naval men. A group of 217 Saudi Arabian naval recruits were examined clinically, radiographically, and microbiologically for the prevalence of Streptococcus mutans. Caries experience was considerably lower than in US recruits of comparable age and showed a significant positive correlation with the prevalence of S mutans in dental plaque samples. The distribution of S mutans biotypes and their relationship to dental caries in the Saudi Arabians were studied.


Stress in dental patients undergoing routine procedures. A method was devised to record graphically the stress that patients experience during routine dental procedures. Heart rate was used as the indicator and the variations in it showed which parts of the treatment provoked the maximum stress reactions. This pilot study indicated that by using this method it is possible to study specific dental problems and methods for treating them.


Microprobe analysis of a high Cu amalgam alloy. A new amalgam alloy consisting of spherical particles having a composition of 60% Ag, 27% Sn, and 13% Cu was investigated by microprobe and X-ray diffraction analysis. The alloy seemed to consist of minute dispersion of Cu3Sn, gamma(Ag3Sn), and beta(Ag-Sn). Amalgam made from this alloy exhibited a matrix of gamma1(Ag-Hg) with small reaction phase areas of Cu6Sn5. No gamma2(Sn-Hg) was observed.


Fabrication and characterization of porous-rooted polymethylmethacrylate (PMMA) dental implants. A comparative-agglomeration fabrication technique has been developed to produce polymethylmethacrylate dental implants having a porous coating on the root portion. This process allows control of pore structure enabling ingrowth of either bone or fibrous tissue. The relationships between mechanical properties and pore microstructure have been determined for materials produced by this process. The mechanical properties of the porous coating can be estimated from these relationships.


Synchronized crystal dissolution behavior for tooth enamel and synthetic (NBS) hydroxyapatite. The synchronized cyrstal dissolution hypothesis previously proposed to explain the unusual dissolution behavior of human dental enamel and hydroxyapatite in partially saturated acidic media has been critically examined with dissolution-dialysis transport experiments. The findings are in accord with the hypothesis. A model based upon a variable effective solubility for the hydroxyapatite crystal is proposed.


Collagenolysis by human gingival fibroblast cell lines. Human gingival fibroblast cell lines were initiated in flask cultures from four periodontal patients with the diagnoses of periodontitis (two patients), fibromatosis, and Dilantin hyperplasia. The collagenolytic propensity of these fibroblasts cultivated on collagen-coated cover slips and the inhibitory effect of serum were evaluated by direct microscopic observations.


Diurnal variation in epithelial cell population kinetics of young mouse tongue. The purpose of this study was to determine if there was a  diurnal variation in the DNA synthesis pattern of epithelial basal cells in the dorsum of the mouse tongue between infancy and preadult ages. The pattern of DNA synthesis in the basal cells of mouse tongue in 24-hour periods for different age groups was studied by isotope labeling and radioautography. A strong diurnal variation was found in the pattern of DNA synthesis with the degree of variation dependent on the age of the experimental groups.


The turnover of collagen in the dental pulp of rat incisors. The turnover of collagen in the dental pulp was studied using H3-proline and microchemical techniques. The incorporation of label into the whole tissue was very high, with most of the label being incorporated into the noncollagenous substances. The rate of disappearance of label from collagen approximated the disappearance of label from noncollagenous components, suggesting that the whole pulp was undergoing rapid remodeling. There seems to be more than one metabolic pool of collagen.


Further evidence for jaw opening reflex as pain response in rabbit.


Speed of jaw movement during mastication and clenching tasks in man.


Quantitation of an antibacterial agent in a dentifrice by thin-layer chromatography.


In vivo replica technique for scanning electron microscopy.


Microhardness of sclerotic dentin.

Microhardness of sclerotic dentin.


X-ray microbeam diffraction analyses on a tooth discolored by tetracycline.


A review of dental school accreditation: development and current philosophy.


Formal training in education for dental educators: a pilot program.


A training model for alternative teaching methods for a school of dentistry. In the summer of 1974 the University of Louisville contracted with an educational consulting team to develop a training program to build alternative teaching methods for the school's educational program. A four-stage model consonant with the goals and objectives of the administration, the faculty, and the consultants was established. The uniqueness of the model was its personalization to individual faculty members' needs and educational interests. While other intervention processes which address the cognitive aspects of education have been developed, this model focused upon the real day-to-day problems faced by faculty. The model addressed itself to people rather than to theory and dealt with interpersonal behavior, communication skills, and classroom dynamics in education. This paper described the four phases of the training model developed for the University of Louisville and discusses the results of using the model.


An evaluation system for preclinical and clinical endodontics. One of the most difficult tasks, facing the dental educator is the evaluation of students' preclinical and clinical performance. This article describes the development of an evaluation system that eliminates some of the problems associated with the assessment of psychomotor skills including rater subjectivity and the validity of evaluation instruments. The evaluation system discussed is currently being used by the Department of Endodontics at the Louisiana State University School of Dentistry for both preclinical and clinical endodontics. The article focuses on the development of the system, use of the clinical rating scale, and an assessment of the system's effectiveness.


Seminar format for large classes.

Seminar format for large classes.


Dental practice management game: a new tool for teaching practice management. This paper describes the structure of a dental practice management game. The game covers a wide spectrum of management decisions in setting up and in running a dental practice. The decisions considered include practice location, the form of practice, staffing mix, salaries, and the purchasing or leasing of equipment. The game also covers major daily, monthly, and yearly decisions including forecasting patient load, economic analysis, and scheduling of patients, workers, and operatories. The paper also discusses the cost and time required to run the game. Many sample printouts are included.


A semi-instructed method for teaching management techniques.


The dental educational environment as perceived by the female student.


Time for an honest look at basic sciences.


Cancer screening.

Cancer screening.


Chair improvement.

Chair improvement.


Dental society's own clinic.

Dental society's own clinic.


Dr. Reyto article.

Dr. Reyto article.


No better feeling.

No better feeling.


Poor choice of works.

Poor choice of works.


Summary of the 1975-1976 annual report of the Council on Dental Education.


Dental student attrition.

Dental student attrition. In summary, the attrition rate for the recent dental school freshman classes has been reduced to 3 1/2 %. The national freshman enrollment of US dental schools can be expected to have approximately a 7% attrition rate by the time of graduation. The reasons for student withdrawal are evenly divided between personal and academic problems. The academic problems are experienced with slightly more frequency in nonclinical courses than in technique courses, both areas of difficulty being predicted significantly by DAT scores. Finally, the attrition rate for women is higher than for men, which has been true to a significant degree in the first-year classes during the past two years, as well as for all four years of dental school. However, no specific reason has been identified for this difference.


Factors influencing the choice of practice location for recent dental graduates. A survey of factors that influenced the selection of practice location was carried out among 1971 dental school graduates. The decision process involved in this selection is a complex phenomenon that involves many personal and community value judgments. The two most important stated reasons appear to be geographic preference and recreational and cultural advantages. As in previous surveys of this type, the place of rearing seems to exert a strong influence, although less than 25% of the respondents indicated this in their three choices of most influential factors. In point of fact, however, 47% of the respondents did locate their practice near their place of rearing. This is further reinforced by the place of rearing of their spouses, if they were married. The respondent's father's occupation had some influence, but this was less significant than the other factors. Choice of specialty in all areas except dental public health, oral pathology, and orthodontics strongly influenced the respondent toward an urban practice. More rural dentists, as one would expect, were self-employed and without a partner.


US dental schools "build" firm foundation in education.


Interstate relocation of dentists, 1971-1975. Bureau of Economic Research and Statistics.


A survey of 4,793 oral lesions with emphasis on neoplasia and premalignancy. A survey was taken of a selected group of 4,793 oral lesions submitted to the oral pathology biopsy service between 1950 and 1970. About two thirds of all the specimens examined microscopically were classified as inflammatory, infectious, or reactive hyperplasia. Of the 12.6% of the sample classified as neoplasms, one of every five was malignant. Three of every four of the malignant neoplasms were microscopically diagnosed as squamous cell carcinomas. Benign neoplasms were most common in ages 40 to 60, whereas premalignancies and malignancies were most commonly discovered in the slightly older age group of 50 to 70. Although malignant neoplasms were found more often in men than women, there was a striking increase in the incidence of malignancies in women in the second ten-year period of the study. There were unexplainably few malignant neoplasms found in blacks. Patients should be taught to recognize the early signs of oral premalignancy and malignancy through the use of a simple method of self-examination at home. They should be discouraged from the frequent use of tobacco and alcohol, which have long been known to be predisposing factors in the production of oral squamous cell carcinomas.


Cold sterilization of gutta-percha cones with formocresol vapors. Cold sterilization of gutta-percha cones was accomplished by exposing them to formocresol vapors for 16 hours. The data obtained from this in vitro study indicate that gaseous sterilization with formocresol vapors is effective against a variety of gram-positive, gram-negative, and spore-forming microorganisms.