Detection and isolation of an endoperoxide intermediate in prostaglandin biosynthesis. An earlier proposed endoperoxide intermediate in the biosynthesis of prostaglandins was detected in short-time incubations of arachidonic acid with the microsomal fraction of homogenates of sheep vesicular glands. Conversion of the endoperoxide into prostaglandin E(2) was stimulated by reduced glutathione but suppressed by p-mercuribenzoate and N-ethylmaleimide. The methyl ester of an unknown compound was isolated by solvent extraction and thin-layer chromatography after short-time incubation of arachidonic acid with the microsomal fraction and p-mercuribenzoate. This derivative was identical to the methylester of the endoperoxide, as shown by its conversion into the methyl esters of 11-dehydroprostaglandin F(2alpha) and prostaglandin E(2) by spontaneous rearrangement and its conversion into the methyl ester of prostaglandin F(2alpha) by mild chemical reduction. The smooth muscle-stimulating activity of the endoperoxide ester on the isolated rabbit aortas trip was 4- to 8-times higher than that of the methyl ester of prostaglandin E(2).


Transductional and structural principles of the mitochondrial transducing unit. The electromechanochemical model has been reformulated to take account of the close connection between energy coupling and catalysis. In catalysis the protein is programmed to utilize thermal energy to produce local strains in the catalytic cavity and to generate conformational states that favor substrate --> product conversion. Energy coupling involves transfer of vibrational energy through the protein. Underlying these two energy transductional maneuvers is the concept of a pulsating protein capable of redistributing electromechanochemical potential energy in a programmed fashion. The mitochondrial supermolecule has been defined, and it has been shown how the supermolecule concept rationalizes the coupling options, the stoichiometry of the coupling complexes, and the multistep character of electron transfer.


Nuclear magnetic resonance study of the thermal denaturation of ribonuclease A: implications for multistate behavior at low pH. The thermal denaturation of ribonuclease A has been studied by use of Fourier transform nuclear magnetic resonance by monitoring the imidazole C-2 proton resonances of the histidine residues as a function of temperature at pH 1.3. As the temperature is raised, a slow chemical exchange process results in the disappearance of the peaks corresponding to the native conformation and the appearance of a single peak corresponding to histidine in the denatured state. The disappearance of the native peaks is not simultaneous, implying that at least two regions of the molecule denature at different temperatures. Also, fast chemical exchange processes result in small chemical shifts that appear to be related to local conformational changes. The observed phenomena have been shown to be reversible by the measurement of absorbance at 278 nm, enzyme activity, and nuclear magnetic resonance spectroscopy. The results of this equilibrium study support a multistate denaturation mechanism for ribonuclease A at pH 1.3.


Coagulation of blood plasma of guinea pig by the bone matrix. Optimal amounts of demineralized bone matrix possess the ability to coagulate platelet-free heparinized, citrated, and oxalated blood plasmas of guinea pigs. Clotting constituents become denatured in contact with the insoluble coagulant proteins. Quantities in excess of optimal modify plasma so that it does not gel when thrombin is added. The newly described coagulant effects are not restricted to the bone matrix, but are present also in the demineralized matrices of tooth and ivory, and in denatured tendon as well. They are regulated properties that were not demonstrated in mineralized bone or native tendon. The coagulant attributes of bone matrix are consistent with those of electropositive polymers of a specific sort.


A protein of molecular weight 78,000 bound to the polyadenylate region of eukaryotic messenger RNAs. Two distinct proteins were found to be tightly bound to the heterogeneous messenger RNAs associated with polysomes in mouse L cells and rat hepatocytes. The molecular weight (78,000) of the larger of these two proteins is identical to that of the protein previously found associated with rabbit globin messenger RNA. This protein is shown to be bound to the adenylate-rich region of messenger RNA. The molecular weight of the smaller protein associated with messenger RNAs from hepatic and L-cell polysomes is similar to that found in globin messenger ribonucleoprotein.


Development of locomotor patterns in the absence of peripheral sense organs and muscles. The role of peripheral sense organs and muscles in specifying the circuitry of the central nervous system during ontogeny was tested in larval lobsters. Presumptive locomotor appendages, the abdominal swimmerets, were extirpated before their differentiation. Electrophysiological recordings made 2-4 weeks later from the corresponding motor nerves showed that, despite the absence of the target muscles and sense organs, normal reflexes and normal patterns of rhythmic locomotor output appeared in the swimmeret motoneurons at the usual developmental stage. Therefore, target muscles and sense organs are unnecessary to the differentiation of normal motor output patterns in this simple invertebrate locomotor system.


Flavin 1, N 6 -ethenoadenine dinucleotide: dynamic and static quenching of fluorescence. Flavin 1,N(6)-ethenoadenine dinucleotide (epsilonFAD) was prepared by the action of chloroacetaldehyde on flavin adenine dinucleotide. This compound, which has two potential fluorophores, epsilon-adenine and isoalloxazine, shows extremely efficient energy transfer from the former to the latter. The fluorescences of both moieties are greatly diminished in the intact molecule. Determination of the fluorescence yields and lifetimes leads to the conclusion that at 20 degrees in neutral aqueous solution epsilonFAD exists mainly (90%) as an internally complexed or stacked form.


Pediatric ophthalmic dispensing.

Pediatric ophthalmic dispensing.


Stress-induced bioelectric potentials in the dentoalveolar complex.


Periodontal bone support and tooth length in orthodontically treated and untreated persons.


Surgical-orthodontic correction of open-bite malocclusion. Report of a case.


Effects of form and function on swallowing and the developing dentition.


Growth and prediction of the skeletal and soft-tissue profiles.


Continuous-flow isoelectric focusing and isotachophoresis.


Analytical and preparative isoelectric focusing in gel-stabilized layers.


Immuno-isoelectrofocusing.

Immuno-isoelectrofocusing.


Detection of Ampholine patterns.

Detection of Ampholine patterns.


Electrofocusing of grain proteins from wheat genotypes.


Small-scale fractionation of proteins and nucleic acids by isoelectric focusing in polyacrylamide gels.


Some experiences in the fractionation of proteins by isoelectric focusing.


Conformational studies on proteins by isoelectric focusing.


Activity of "early" and "late" dehydrofolate reductase in induced abnormalities of mammalian embryogenesis.


Microheterogeneity and allomorphism of proteins.


The use of gel isoelectrofocusing in monitoring chemical modifications of proteins.


Physicochemical properties of the carrier ampholytes and some biochemical applications.


Isoelectric focusing and the study of interacting protein systems: ligand binding, phosphate binding, and subunit exchange in hemoglobin.


Some clinical biochemical aspects of isoelectric focusing.


Isoelectric focusing of myosin and other muscle proteins in polyacrylamide gels.


The use of gel electrofocusing in the study of human hemoglobins.


Isoelectric focusing in polyacrylamide gels.


Multiple forms of mammalian RNA polymerase displayed by gel electrofocusing.


The use of isoelectric focusing to study components of the human plasma kinin-forming system.


Separation of Australia antigen and some bacterial proteins by isoelectric focusing in polyacrylamide gels.


Some theoretical and practical aspects of isotachophoretical analysis.


The choice of electrolyte conditions for isotachophoretic separations.


Instability of pH gradients formed by isoelectric focusing in polyacrylamide gel.


Analytical gel isotachophoresis of proteins with carrier ampholyte spacers.


Determination of pH differences occurring during isotachophoresis with different systems of leading and terminating electrolytes.


Multiphasic zone electrophoresis, IV. Design and analysis of discontinuous buffer systems with a digital computer.


Focusing in continuous-flow electrophoresis systems by electrical control of effective cell wall zeta potentials.


Toward a unified electrophoretic viewpoint.


Analytical scanning isoelectrofocusing.

Analytical scanning isoelectrofocusing.


Rapid isoelectric focusing in density gradient columns.


Isoelectric focusing in free Ampholine solution and attempts at isoelectric focusing in pH gradients created in ordinary buffers.


Cholinesterase and esterase activity in normal and dystrophic human muscle.


Potential hazards of expiratory "retards" in commercial production.


The Cape Minor Ventilator: a functional analysis and clinical appraisal.


Influence of saliva on epidermal cancer in rat induced by water-or fat-soluble carcinogens.


Roentgenographic assessment of overhanging margins of dental restorations. I. Significance of variations in horizontal projection.


Occlusal interferences in children with bruxism.


Cranial morphology and dental arch dimensions in children with Angle class II, div. 2 malocclusion.


Detail reproduction with alginates and dental stones.


Preleukemia. The hematologic syndrome preceding acute leukemia.


Acute lymphoblastic leukemia with pulmonary complications.


Granule assembly in precursors of human leukemia granulocytes. In human leukemic myeloblasts, the granule enzymes beta-glucuronidase, myeloperoxidase and acid phosphatase were associated with light particles of varying densities that were separable from each other by means of zonal density gradient centrifugation. In more mature granulocytic cells of chronic myelogenous leukemia the three enzymes merged within a single group of denser particles; such particles were absent in myeloblasts. Myeloblast particles had two to three times higher activity of beta-glucuronidase and acid phosphatase, but only one-tenth of the myeloperoxidase activity. Some of the cationic proteins and lysozyme were not found in leukemic myeloblasts but were present in particles of chronic myelogenous leukemia; alkaline phosphatase was absent from both types of leukemic cells.


Professionalism in management.

Professionalism in management.


A component society patient relations committee.


A constituent society review system.

A constituent society review system.


The relevance of health maintenance organizations.


State dental political action committees.


Continuing education registry program: a pilot study.


Legislative developments.

Legislative developments.


Reports and discussion of questions and proposals from concurrent discussion groups.


Decision making as it relates to association management: board of directors, committees, membership and public at large.


Honoraria-fees for clinicians and essayists.


The hygienists' story in Rhode Island. A special report.


The unionization movement for health professionals.


The young professionals. Dental student loan programs.


The young professionals. The dental student and the dental profession.


The young professionals. Involving the younger dentist.


A report on priorities--dental care programs.


Denturism in America--1973.

Denturism in America--1973.


The scoreboard on political action committees.


A survey of membership attitudes--a profile.


High catecholamine essential hypertension: clinical and physiological characteristics.


ABO blood groups in primary carcinoma of the liver.


The incidence of oxyphenisatin ingestion in active chronic hepatitis: a prospective controlled study of 29 patients.


Gastrin, age and the gastric mucosa.

Gastrin, age and the gastric mucosa.


On the aetiology of hypertrophic pulmonary osteoarthropathy in bronchogenic carcinoma: lack of relationship to elevated growth hormone levels.


Pseudohypertrophic muscular dystrophy of childhood: an epidemiological survey in Victoria.


Immunological studies of the eye changes of thyrotoxicosis.


The effect of haemodynamic changes induced by angiographic contrast media on aortic regurgitation in the sedated dog.


The use of a new mode of therapy in the management of orthostatic hypotension.


Malignant changes arising in a dyshormonogenetic goitre due to an isolated thyroglobulin deficiency.


Successful removal of an intramural fibroma of the heart.


Systemic lupus erythematosus in a Chinese woman presenting with gangrene of the fingers.


Pulmonary candidiasis treated with 5-fluorocytosine.


Bronchogenic carcinoma causing non-terminal saccular bronchiectasis.


Bradycardia in acute myocardial infarction.


Gastrin and parietal cell antibodies.

Gastrin and parietal cell antibodies.


The detection of abnormalities in the jaws. A survey.


Susceptibility of tooth surfaces to carious attack. A longitudinal study.


Colonisation of dental units by water bacteria.


The selection and properties of materials for dental practice. 4. Dental amalgam.


Oral tuberculosis. Case reports.

Oral tuberculosis. Case reports.


Dental treatment with general anaesthesia for handicapped patients.


Internal resorption. Diagnosis and treatment.


Failure to establish control over tics in the Gilles de la Tourette syndrome with behaviour therapy techniques.


Hiring: what to look for in a new employee.


Incisive canal cyst. History and clinical findings.


A study on the main factors influencing the reduction of birth rates in the districts of Cheng-Chung, Chung-Shan and Nei-Hu in Taipei City.


The serum mucoprotein in Curling's ulcer.


Further studies on the immunogenic properties of photooxidized Formosan snake venoms, with special reference to a trial preparation of polyvalent antivenin using photooxidized multiple venom antigens--second report.


Immediate postoperative pylon fitting for lower extremity amputation. Experience with 30 cases compared to 35 cases with conventional method.


Studies of the effect of the salt iodization on endemic goiter in Taiwan. 3. Urinary iodine excretion of school children.


The effect of physical medicine in the treatment of the contractures of extremities after fracture.


Comparative study in the management of frozen shoulder.


Summary of patient interpretation after experiencing periodontal therapy.


The professional corporation. A 1973 appraisal.


Dentist relates missionary experience.

Dentist relates missionary experience.


The HMO and dental service.

The HMO and dental service.


Children speak out on cigarette smoking.


For professional success: understand your patient.


Maternal anxiety and children's behavior during dental procedures.


Identification of the chromosomes that control malignancy.


Cystic fibrosis: in vivo reversal of the ciliostatic character of serum and parotid secretions by heparin.


Natural callus-like tissue produces vegetative buds on the leaves of the monocotyledon Haemanthus cinnabarinus Decaisne (Amaryllidaceae).


Cystic fibrosis: in vitro reversal of the ciliostatic character or serum and salivary secretions by heparin.


Multiplication of Toxoplasma gondii in enucleated L cells.


Hypertension.

Hypertension.


Don't die through neglect.

Don't die through neglect.


Who is man?

Who is man?


Organisation of industrial relations.

Organisation of industrial relations.


Studies of extended families.

Studies of extended families.


A complement fixation test for the serological diagnosis of leptospirosis in pigs experimentally infected with serotype Pomona.


The incidence of Haemonchus contortus infections in sheep abomasa received at animal health laboratories in New Zealand.


Transport of calves by road.

Transport of calves by road.


Increased capillary permeability to  125 I-labeled albumin during experimental hemorrhagic shock.


[Gunshot wound of the face: report of a case].


Therapeutic interference studies: mechanisms of interpolymer competition for dyes.


An unappreciated aspect of prevention.

An unappreciated aspect of prevention.


Dental surgery assisting as a career.

Dental surgery assisting as a career.


Credit cards ... the interest rate trap.


Communications.

Communications.


The d.a.; your filing system.

The d.a.; your filing system.


Tumors of the mandible and maxilla in children. II. A study of 14 primary and secondary malignant tumors.


Ketamine anesthesia--second thoughts.

Ketamine anesthesia--second thoughts.


Magic and dentistry.

Magic and dentistry.


Chronic subdural hematoma in childhood acute leukemia.


The differentiation and early treatment of functional malocclusions.


Pomp combination chemotherapy of adult acute leukemia.


United? Yes. Unionized? No.

United? Yes. Unionized? No.


Unveiling of U of I's College of Dentistry Building, phase I.


The implant.

The implant.


World is a stage for 3 Chicago amateur radio operators. Dentists involved in life and death situations.


What the dentist should know about sickle cell anemia.


Questions and answers on fluoride.

Questions and answers on fluoride.


The dental assistant's role in oral cytology.


A look at where we have been and where we are in dental assisting. I.


A dental assisting program in a dental school setting.


Communications for the dental team.

Communications for the dental team.


Use of the articulator.

Use of the articulator.


Little things I've learned from 60 years in black Harlem.


Repeat after me. How to break old habits and teach new ones, to bring home the message of prevention? Your best tool is repetition.


Inside track to investment profits.

Inside track to investment profits.


How to make money with money.

How to make money with money.


So you want to build a building: selling the property.


Cutting the high cost of higher education.


Constructing a composite pontic in a single visit.


Modified appliance to control tongue-thrust.


Proper dowel preparation for endodontic treatment.


Dental continuing education expands.

Dental continuing education expands.


New crown for dentistry.

New crown for dentistry.


Morphological comparison of endodontically prepared root canals.


A vestibular model--simplified procedure for progress records.


Redesigned office and operatory increase efficiency.


A new high-strength composite-type cement for orthodontic bands.


Technic clinic. A back-action arch.

Technic clinic. A back-action arch.


Tax tips for the dentist.

Tax tips for the dentist.


A dental manpower study of the San Mateo County Dental Society.


Pharmaceutical services at the USC School of Dentistry.


Antecedent-consequent variables of N2O-O2 administration. I. Behavioral profile of the patient.


Giving plaque the flak. North York's grade 6 flossing program promotes healthy mouths.


Are you a financial success?

Are you a financial success?


The management of a periodontal patient.


In vitro and in vivo studies on a composite resin for the repair of incisal fractures.


Diet counseling to prevent caries.

Diet counseling to prevent caries.


Functional disturbances of temporomandibular joints.


The cartilage of the mandibular condyle.


Comparative functional anatomy of temporomandibular joint.


Classification of the secondary cardiomyopathies. The pathologist's view.


The nine stages of human development, and the index of teething (IT). II.


Low-level goals in dental schools.

Low-level goals in dental schools.


Dental costs and incomes rose in 1971.

Dental costs and incomes rose in 1971.


Vietnam dental education project.

Vietnam dental education project.


The dentist-patient relationship.

The dentist-patient relationship.


Pit and fissure sealant--its place in preventive dentistry and a technique for its application.


Roadmenders in miniature.

Roadmenders in miniature.


Electrical stimulation of bone growth.

Electrical stimulation of bone growth.


Preventive dentistry in action. 3.

Preventive dentistry in action. 3.


The many uses of a pondent.

The many uses of a pondent.


The halogenation of water.

The halogenation of water.


Sickle-cell anemia: chronology, natural history and implications for dental practice.


The influence of different fixatives on the histochemical reactivity of dentin and predentin.


Effect of hydrocortisone on rat tooth germ. Morphological study.


An introduction to clinical trials.

An introduction to clinical trials.


Electricity in local anesthesia. Test of 'Sin Dolar'.


The dentist in politics--participant or victim?


The British are coming.

The British are coming.


High sucrose snacks: are they doubly dangerous?


Cherubism: report of a case.

Cherubism: report of a case.


An evaluation of plaque disclosants: clinical significance.


Proliferation, survival and malignancy of chloroleukaemia cells grown in diffusion chambers in vivo.


The surgical treatment of peptic ulcer. A 15-year review.


Effect of vincristine on the megakaryocyte system in mice.


Labelled fibrinogen. A brief review.

Labelled fibrinogen. A brief review.


Oral surgery Hall of Fame.

Oral surgery Hall of Fame.


Expertise or expertease?

Expertise or expertease?


New specialty needed.

New specialty needed.


Cryosurgery of oral white lesions.

Cryosurgery of oral white lesions.


Assessment of recovery by means of the Phystester: preliminary report.


The current status of halothane.

The current status of halothane.


Choice of treatment of orbital floor fractures as part of facial fractures.


Case 2, part 1.

Case 2, part 1.


Adenomatoid odontogenic tumor.

Adenomatoid odontogenic tumor.


Central hemangioma of the mandible: report of case.


Large sublingual dermoid cyst: report of case.


Monostotic fibrous dysplasia of the maxilla: report of cases.


Hodgkin's disease of the mandible: report of case.


Non familial cherubism: report of two cases.


Reduction of thrombophlebitis associated with indwelling catheters.


Corrosion of metal fracture fixation appliances.


Cells transformed by human Herpesvirus type 2 transcribe virus-specific RNA sequences shared by Herpesvirus types 1 and 2.


Site of the amino-acid substitution in haemoglobin Seattle (  2  A    2  70 Asp ).


Assignment by deletion of human red cell acid phosphatase gene locus to the short arm of chromosome 2.


Structure of haemoglobin Seattle.

Structure of haemoglobin Seattle.


Redistribution of tosylarginine methylester hydrolase activity after fertilization of sea urchin (Arbacia punctulata) eggs.


Selective killing of macrophages by amanitin-albumin conjugates.


Effect of human chorionic somatomammotrophin and human chorionic gonadotrophin on phytohaemagglutinin-induced lymphocyte transformation.


Ophthalmic artery stenosis and diabetic retinopathy.


Diabetic retinopathy. Human and experimental studies.


Preretinal macular fibrosis. (An analysis of 90 cases).


Recent developments in diagnostic ultrasound.


The application of ultrasonics in ophthalmology.


Analysis of some unusual and difficult visual field defects.


A new cine fluorographic technique and its application to investigation of the retinal circulation.


The value of radio-isotope techniques in the diagnosis of ocular tumours.


Hereditary aspects of pigmentary retinopathy.


Choroidal vascular aspects of degenerations of the retinal pigment epithelium.


Detection of heterozygotes in families with X-linked pigmentary retinopathy by measurement of retinal rhodopsin concentration.


Electroretinography, electro-oculography and fluorescence angiography in heredo-macular degenerations.


Quantitative slit-image photography of the lens.


Primary retinal pigmentary degeneration.


Post-operative Haemorrhagic retinopathy (haemodynamic studies).


Orbital decompression in thyroid disease.


Factors affecting recovery of visual acuity following detachment of the retina.


Direct goniotomy.

Direct goniotomy.


Treatment of the detached immobile retina.


A combined glaucoma-cataract operation.

A combined glaucoma-cataract operation.


Angiography and differential diagnosis of orbital tumours.


Pre-retinal traction membranes.

Pre-retinal traction membranes.


Symposium on the macula.

Symposium on the macula.


Macular oedema.

Macular oedema.


Diabetic maculopathy. A preliminary report.


The evolution of subpigment epithelial neovascularization in senile disciform macular degeneration.


The effect of light radiation on blood vessels and membranes.


Options in the treatment of macular diseases.


Visual aids in macular disease.

Visual aids in macular disease.


Medial decompression of the orbit for endocrine exophthalmos.


The indications for refractive keratoplasty.


Keratophakia.

Keratophakia.


The unusual.

The unusual.


The sterilization of surgical instruments and solutions.


Congenital porphyria: general and ocular manifestations.


Superior limbic keratoconjunctivitis.

Superior limbic keratoconjunctivitis.


The aqueous flow and permeability of the blood-aqueous barrier in retinal detachment.


Epidemic haemorrhagic conjunctivitis in London 1971: a conjunctival picornavirus infection.


Reduced in-patient stay following cataract extraction.


Practical aspects of strabismus management. The achievement of a functional result in squint in early childhood.


Visual prognosis in anterior displacement of the lens.


The surgical management of esotropia in infancy.


Aspects of horizontal muscle surgery, particularly in Duane's syndrome.


Surgical aspects of vertical squint.

Surgical aspects of vertical squint.


The role of the oblique muscles.

The role of the oblique muscles.


"Superior oblique sheath syndrome" with abnormal insertion.


Perforatokerato-prosthesis 60 cases, 1967-72.


Surgical treatment of primary open-angle glaucoma.


Bracken retinopathy in sheep.

Bracken retinopathy in sheep.


Microsurgical methods in glaucoma.

Microsurgical methods in glaucoma.


Traumatic central retinal artery occlusion.


Emulsification of the cataractous lens.

Emulsification of the cataractous lens.


Epidemic keratoconjunctivitis. A virological and clinical study.


Refractive keratoplasty.

Refractive keratoplasty.


A survey of the eyes of some East Greenland Eskimos.


Rubella cataracts in one of twins.

Rubella cataracts in one of twins.


The treatment of traumatic hyphaema.

The treatment of traumatic hyphaema.


The fields in subclavian steal.

The fields in subclavian steal.


Eye signs in neuroblastoma.

Eye signs in neuroblastoma.


Treatment of diabetic retinopathy with light coagulation.


Four years Binkhorst lens implantation.

Four years Binkhorst lens implantation.


A simple method of cryosurgery in desperate cases of glaucoma.


Photocoagulation in advanced diabetic retinopathy, with special references to vitreous retraction.


Sparing of the macula.

Sparing of the macula.


The host-parasite relationship: digestive capcity in vitro.


The clinical use of the argon laser.

The clinical use of the argon laser.


Leber's congenital amaurosis: a genetical and pathological study.


Electrodiagnosis of the visual system of the young child with defective vision.


Experimental cryoapplication with variations in the pressure exerted on the sclera.


Clean eye medication.

Clean eye medication.


Our experiences of light coagulation in the treatment of diabetic retinopathy.


Cytogenetic studies in haematological disorders which may terminate in acute leukaemia.


Anerythraemic Di Guglielmo syndrome. Report of a case.


Unilateral versus bilateral electroconvulsive therapy. Investigations into the therapeutic effect in endogenous depression.


Corneal ring ulcer as the presenting manifestation of acute monocytic leukemia.


"Een ballon opblazen". A method of anaesthetic induction in children.


An assessment of the oxygen tensions obtained with pre-mixed 50 per cent nitrous oxide and oxygen mixture (Entonox) used for pain relief.


The effect of repetitive stimulation on the jaw-opening reflex in the cat.


Caries control in the albino rat with chlorhexidine gluconate (Hibitane).


Cortical bone structure of the pig mandible.


Distribution of symmetric and asymmetric patterns of caries attack in human permanent maxillary incisor teeth: genetic implications.


Differentiation of lingual filiform papillae of the rat in organ culture.


The presence of iso- -amylases in human saliva.


Effect of fluoride on carbon dioxide and acid formation in salivary sediment mixtures incubated with glucose.


The strontium content of bones and teeth of human foetuses.


The vitamin requirements of some oral streptococci.


Synthesis of a broth levan by a cell-bound levansucrase from Streptococcus salivarius (SS2).


A biochemical study of collagen in the periodontal ligament from erupting and non-erupting bovine incisors.


Ultrastructure of the dorsal lingual epithelium in human embryos and foetuses.


In-vitro observations on fluid flow through human dentine caused by pain-producing stimuli.


Streptococci isolated from plaque in subjects rinsing with chlorhexidine.


Immunologic rebound after cessation of long-term chemotherapy in acute leukemia. II. In vitro response to phytohemagglutinin and antigens by peripheral blood and bone marrow lymphocytes.


A study on inhibition of masseteric  -motor fibre discharges by mechanical stimulation of the temporomandibular joint in the cat.


Methylphenidate therapy in primary alveolar hypoventilation.


Cell distribution and proliferation pattern of a transferable acute leukemia in rats.


Splenic sequestration crisis in childhood myelogenous leukemia.


Binding of  13 C-enriched  -methyl-D-glucopyranoside to concanavalin A as studied by carbon magnetic resonance. Binding of alpha-methyl-D-glucopyranoside, uniformly enriched with 14% (13)C, to zinc and manganese derivatives of concanavalin A at pH 5.6 was studied by pulsed Fourier transform carbon magnetic resonance techniques. Spin-lattice relaxation (T(1)) of the [(13)C]carbons of the sugar was measured in the absence and presence of the two transition metal derivatives of the protein. In the presence of the manganese derivative of concanavalin A, selective relaxation of the sugar carbons was observed. The values for T(1) reflect different distances between the carbons of the bound sugar and the manganese ion. Calculation of the distance between the manganese ion and each carbon of the sugar permit the 3-dimensional orientation of the bound sugar to be determined relative to the transition metal site in the protein. The results indicate that alpha-methyl-D-glucopyranoside binds to the protein in the Cl chair conformation with its 3- and 4- carbons closest to the manganese ion at a mean distance of 10 A.


Nuclear magnetic resonance spectroscopy.  13 C Fourier transform spectra of   8 - and   9 -tetrahydrocannabinol. Carbon-13 nuclear magnetic resonance spectra have been taken of Delta(8)- and Delta(9)-tetrahydrocannabinol. The absorptions have been assigned to specific carbons with the aid of off-resonance and selective proton-decoupling experiments, as well as by chemical-shift comparison with model compounds.


Concanavalin A derivatives with altered biological activities. Chemical derivatization of tetrameric concanavalin A (Con A) with succinic anhydride or acetic anhydride converts the protein to a dimeric molecule without altering its carbohydrate-binding specificity. At low concentrations, the dose-response curves for the mitogenic stimulation of mouse spleen cells by native Con A and succinyl-Con A are similar. Above lectin concentrations of 10 mug/ml, however, the response to Con A is diminished, while that for succinyl-Con A does not decrease until much higher doses are reached. We have attributed this difference mainly to the higher rate of cell death induced by the native Con A molecule. Con A also shows a greater capacity than succinyl-Con A to agglutinate sheep erythrocytes and to inhibit cap formation by immunoglobulin receptors on spleen cells. Moreover, at low concentrations, Con A induced its glycoprotein receptors to form caps, but succinyl-Con A did not induce cap formation. Addition of antibodies directed against Con A to succinyl-Con A bound on cells restored the properties of agglutination, inhibition of immunoglobulin receptor cap formation, and induction of cap formation by Con A receptors. Similar results have been obtained for acetyl-Con A. These data suggest that the altered biological activities of succinyl-Con A and acetyl-Con A are attributable to their reduced valence.


Oligoclonal IgG antibody response in the central nervous system to different measles virus antigens in subacute sclerosing panencephalitis. Agarose electrophoresis of cerebrospinal fluid from two patients with subacute sclerosing panencephalitis revealed in both cases several homogeneous bands in the intermediate and basic gammaglobulin region. The bands were identified as IgG with various degrees of kappa or lambda light-chain restriction in crossed immunoelectrophoresis. Homogeneous IgG bands were separated by preparative agarose electrophoresis and were found to represent measles virus-specific antibodies. Antibody activities against different virus products (hemolysin, hemagglutinin, and nucleocapsids) were carried by different populations of IgG. In both cerebrospinal fluid materials, antibodies to the virus hemolysin and to virus nucleocapsids were found to be relatively more basic than the antibodies to virus hemagglutinin, which appeared in the basic intermediate gammaglobulin region. We conclude that the oligoclonal IgG bands in cerebrospinal fluid of patients with subacute sclerosing panencephalitis represent homogeneous measles virus antibodies. In some instances, the IgG bands appeared to fulfill criteria of monoclonality on the basis of their electrophoretic homogeneity, selective light-chain type, and specific antibody activity.


Regulation by N gene protein of phage lambda of anthranilate synthetase synthesis in vitro. The N protein of bacteriophage lambda is a positive regulator of early lambda gene expression. In a lambdatrp transducing phage, lambdatrp46Nam, the synthesis of trp enzymes in vivo is also dependent on the presence of active N protein. The DNA of this phage has been used in a protein-synthesizing system in vitro to develop a biochemical assay for the activity of the N protein. From the following observations it appears that it is the N protein itself that stimulates trp enzyme synthesis in vitro. An activity that stimulates trp enzyme synthesis can be made in vitro by lambdaN(+) DNA but not by lambdaNam DNA. This activity can also be detected in extracts of induced lambdaN(+) lysogens but not of lambdaNam lysogens. Furthermore, the activity is temperature sensitive in similar extracts of lambdaNts lysogens. No such activity is detectable in extracts of induced lysogens of lambdaimm(21). This phage makes all lambda-coded gene products outside the immunity region, but lacks an N protein activity able to substitute for N(lambda) protein in vivo. Our experiments also show that the action of N protein is inhibited by the cI repressor protein in vivo as it is in vivo.


Chromosomal abnormalities in spleens of New Zealand black mice, a strain characterized by autoimmunity and malignancy. Mosaicism of normal and chromosomally aberrant cells was detected in 14 of 20 spleens from adult New Zealand Black (NZB) mice reared under conventional conditions, a strain that spontaneously develops autoimmunity and lymphoreticular malignancy. No abnormalities were found in marrows from these same animals or in spleens from NZB mice younger than 3 months. The prevalence of chromosomal aberrations was significantly higher in spleens from NZB mice than in spleens from the two other strains studied-SJL/J, which has high frequency of reticulum cell neoplasia and paraproteinemia but no autoimmunity, and BALB/c, which has essentially no autoimmunity and only a low incidence of generalized lymphoid neoplasms and plasmacytomas in ageing animals. Causes for the chromosomal abnormalities in NZB mice are considered in terms of other features in these mice-immunoproliferation, autoimmunity, and the presence of murine leukemia ("C"-type) virus particles.


Ly-4, a new locus determining a lymphocyte cell-surface alloantigen in mice. A new locus is described that determines an alloantigen on the surface of lymphocytes. It differs from loci previously described in that the corresponding antibody, at least in most antisera, reacts almost exclusively with node lymphocytes, and weakly or not at all with thymuslymphocytes. Positive strains include C57BL/6, C57BL/10, C57L, C57BR/cd, and RF; negative strains include BALB/c, C3H, and SJL. The symbol Ly-4 is assigned, with the C57BL/6 allele being Ly-4(b), and the BALB/c allele Ly-4(a).


Isolation of messenger RNA coding for mouse heavy-chain immunoglobulin. A method for purification of the mRNA coding for heavy-chain protein of a mouse G(2a) myeloma (5563) is reported. Complete myeloma protein (H(2)L(2)) specifically binds to the heavy-chain mRNA, and the resultant RNA-protein complex is precipitated with antiserum against 5563 myeloma protein. Cytoplasmic RNA isolated by this method showed two bands of 6.0 x 10(5) and 3.1 x 10(5) molecular weight when analyzed by acrylamide gel electrophoresis. The RNA in the bands contained 1.5% and 8% A-rich regions, respectively. The RNA in each of the bands contained sequences for heavy-chain protein when translated in Xenopus laevis oocytes.


Diazoacetyl subtilisin.

Diazoacetyl subtilisin. Subtilisin reacts at pH 6.8-7.8 with p-nitrophenyl diazoacetate to release p-nitrophenol and form diazoacetyl subtilisin. Although at pH 7.8 this derivative rapidly undergoes hydrolytic cleavage to regenerate active enzyme, the derivative can be trapped by rapidly lowering the pH to 5. Similarly, with (14)C-labeled p-nitrophenyl diazoacetate, the corresponding radiochemically labeled diazoacetyl enzyme can be prepared. Photolysis of this radioactive derivative incorporates radioactivity into the protein, and subsquent hydrolysis gives rise to several radioactive components, which, however, have not yet been identified.


Genetic regulation of octane dissimilation plasmid in Pseudomonas. The enzymes responsible for the oxidation of n-octane to octanoic acid or beyond in Pseudomonas oleovorans are octane inducible and are coded by genes borne on a transmissible extrachromosomal element. The octane to octanoate enzymes induced by octane are repressed by octanol. The chromosome also carries genes coding octanol oxidation enzymes that, in contrast, are induced by octanol, not by octane. The octane plasmid has been transferred from P. oleovorans to several other fluorescent Pseudomonas species. In exconjugants, the presence of both octane and camphor plasmids enhances their segregation rate.


5-Hydroxymethyluracil in the DNA of a dinoflagellate. During the characterization of DNA from the dinoflagellate Gyrodinium cohnii, a large discrepancy was detected between the estimation of guanine + cytosine content from the buoyant density of the DNA in CsCl (56.1% G+C) and from the midpoint (T(m)) of its hyperchromicity induced by a thermal gradient (35.6% G+C). Composition analyses of (32)P-labeled nucleotides revealed an actual G+C content of 41.3%, and the presence of an unusual nucleotide amounting to about 37% of the expected thymidylate in unfractionated DNA-a feature that can explain the aberrant behavior of the DNA. The chromatographic properties of the unusual base and UV spectral analyses of the base and its corresponding nucleotide are consistent with its identification as hydroxymethyluracil. This base is not uniformly interspersed with thymine in the DNA. About 10% of Gyrodinium DNA is contributed by a fraction with low hydroxymethyluracil content, which behaves anomalously in Ag(+)-Cs(2)SO(4) density gradients but not in CsCl.


Complex formation between mycobacterial polysaccharides and fatty acyl-CoA derivatives. The mycobacterial polysaccharides MMP and MGLP, which contain numerous O-methyl-sugar residues, markedly stimulate fatty acid synthesis catalyzed by a multienzyme complex from Mycobacterium phlei [Ilton, M. et al. (1971) Proc. Nat. Acad. Sci. USA 68, 87-91]. When aqueous solutions containing MMP or MGLP and palmitoyl-CoA were chromatographed on Sephadex G-75 under conditions that widely separate the individual components, polysaccharide and fatty acyl-CoA were eluted in a single peak, indicating formation of a molecular complex. Similarly, the mycobacterial polysaccharides associate with the CoA derivatives of C(18), C(20), and C(22) acids to yield complexes containing maximally 1 mol of fatty acyl-CoA per mol of polysaccharide. The formation of these novel complexes may result from hydrophobic interactions between the paraffin chains of the acyl-CoA derivatives and O-methyl-sugar residues of the polysaccharides.


Adaptive linkage disequilibrium between two esterase loci of a salamander. In some populations of the salamander Plethodon cinereus, two polymorphic esterase loci are in linkage disequilibrium. Short-term stability of the linkage disequilibrium is demonstrated by an age class analysis. Long, perhaps very long, term stability is suggested by its distribution. This stability and concordant geographic variation in allelic frequencies imply selective origin and maintenance. Data on the frequencies of two color morphs suggest that formation of the linkage disequilibrium is dependent on the genetic background.


The 3'-terminal nucleotide sequences of bacteriophage lambda DNA. Analyses of radioactive oligonucleotides in endonuclease digests of 3'-terminally labeled lambda DNA revealed the 3' terminal sequence -GTTACG for the l strand and -ACCCGCG for the r strand. These sequences, together with those previously known for the 5' cohesive ends, provide a total of 25 known base-pairs in the vicinity of the termini. When the cohesive ends are paired, the sequence between the nicks can be bisected by a 2-fold rotational axis of symmetry. Five of the first eight base-pairs, on either side of the axis, are rotationally symmetric. This symmetry may be involved in the recognition of the site by an enzyme responsible for formation of the cohesive ends.


Transcription of rat-liver chromatin with homologous enzyme. The product of transcription of rat-liver chromatin with homologous rat-liver Form-B polymerase in vitro is high molecular weight RNA with sedimentation coefficients principally in the range of 18-45 S. The average size is somewhat smaller than that of the heterogeneous high molecular weight RNA synthesized by the endogenous enzyme in vivo (or in isolated nuclei). We have excluded the possibility that this difference can be attributed to degradation of the nascent RNA occurring under the conditions of our experiments. The size of the RNA produced by the homologous enzyme nevertheless approaches that of the natural transcripts much more closely than does that of the RNA produced by bacterial RNA polymerases, which we, in addition to other authors, have found to sediment around 10 S.


NA + -selective ionophoric material derived from electric organ and kidney membranes. Material that increases black lipid-membrane (oxidized cholesterol) conductance has been demonstrated in the acid-soluble fraction of tryptic digests of membrane fractions from Electrophorus electric organ and beef kidney. The conductance change elicited by this material is highly selective for Na(+). The activity of the material was greatly enhanced by passage through DEAE-cellulose. Activity could be destroyed by further incubation with Pronase. Since conductivity increases exponentially with dose of ionophore, the conductive unit may be an oligomer.


Stimulation by insulin of cell elongation and microtubule assembly in embryonic chick-lens epithelia. Both fetal-calf serum and insulin cause cell elongation in explanted chick-lens epithelia from 6-day-old embryos. We show that 1 mug/ml of insulin, like serum, stimulates a doubling of cell length and an assembly of longitudinally oriented microtubules; colchicine treatment inhibits this cell elongation. In contrast to serum, insulin neither promotes further lens-cell elongation nor appreciably stimulates the synthesis of bulk proteins or of delta crystallin under the present conditions. These data indicate that the early morphological events of lens fiber differentiation can be initiated by insulin in a chemically defined, serum-free medium without significant affects upon protein synthesis.


Proton magnetic resonance study of peptide conformation: effect of trifluoroethanol on oxytocin and 8-lysine-vasopressin. The usefulness of 2,2,2-trifluoroethanol titration as a means of distinguishing between intramolecular peptide-peptide hydrogen bonding on the one hand and intermolecular peptide-peptide and peptide-solvent hydrogen bonding on the other has been investigated with neurohypophyseal hormones, and the results have been compared with those of other methods. The chemical shifts (220 MHz) of the resonances of amide NH and aromatic CH protons of oxytocin, lysine vasopressin, deamino-lysine vasopressin, and deamino-8-tosyllysine vasopressin were monitored as the solvent composition was progressively varied from 100% dimethylsulfoxide to 100% 2,2,2-trifluoroethanol. The overall backbone conformation of oxytocin appears to be retained, and possibly somewhat stabilized, during the solvent transition, while the backbone, particularly the acyclic component, of lysine vasopressin and its analogs is subject to solvent-induced perturbation.


Immobilized catecholamine and cocaine effects on contractility of cardiac muscle. Isoproterenol, norepinephrine, and epinephrine covalently bound to glass beads exert a positive inotropic effect on isometrically contracting papillary muscles from cats. Immobilized isoproterenol maintains increases in force and velocity of contraction for more than 5 hr. 1 muM Cocaine potentiates the action of immobilized norepinephrine, isoproterenol, and epinephrine, but not of isoproterenol in solution. The data presented indicate that the effects of immobilized catecholamines are not due to their coming off the glass. The effects observed with cocaine and immobilized catecholamines are not altered by prior treatment of the muscle with reserpine. These results suggest that the major site of catecholamine action is on receptors located on the extended surface of myocardial cells and a post-junctional site for cocaine potentiation.


Messenger RNA for hepatic tryptophan oxygenase: its partial purification, its translation in a heterologous cell-free system, and its control by glucocorticoid hormones. Messenger RNA from rat liver was partially purified by chromatography on cellulose on the basis of its poly(A) content. Microgram amounts of this RNA stimulate protein synthesis manyfold in a heterologous cell-free system, derived from Krebs ascites cells supplemented with reticulocyte initiation factors. The messenger RNA directs the initiation, synthesis, and release of a product that was identified as complete subunits of hepatic tryptophan oxygenase (EC 1.13.1.12) by immunoprecipitation with monovalent antibodies prepared against homogeneous tryptophan oxygenase and subsequent sodium dodecyl sulfate-polyacrylamide electrophoresis of the solubilized immunoprecipitate. This may represent the first complete translation in a heterologous system of a mammalian messenger RNA coding for an enzyme protein. Analysis of the messenger RNA content of the liver after glucocorticoid administration demonstrates that the hormonally enhanced rate of synthesis of tryptophan oxygenase is accompanied by an increased quantity of its corresponding messenger RNA.


Comments on the paper "experimental evidence of an x-ray laser".


Fusion of phospholipid vesicles with viable Acholeplasma laidlawii. When vesicles of dipalmitoyl phosphatidylcholine produced by sonication are mixed with Acholeplasma laidlawii in neutral buffer, a phenomenon occurs that is most readily explained in terms of fusion of lipid vesicle membrane with the mycoplasma cytoplasmic membrane. The mycoplasma can readily accumulate large quantities of the foreign lipid without loss of viability. The added lipids do not remain in patches but diffuse laterally throughout the mycoplasma membrane.


Direct measurement of the pK values of an alkaline Bohr group in human hemoglobin. Proton nuclear magnetic resonance spectra of normal and des-(his 146beta) human hemoglobin in the aromatic resonance region have been compared at different pH values. From these measurements, a pK value for histidine 146beta of 7.1 in carbonmonoxyhemoglobin and 8.0 in deoxyhemoglobin has been found. These pK values confirm the proposed role of histidine 146beta in the alkaline Bohr effect.


Transfer of genetic information by purified metaphase chromosomes. Transfer of genetic information from isolated mammalian chromosomes to recipient cells has been demonstrated. Metaphase chromosomes isolated from Chinese hamster fibroblasts were incubated with mouse A(9) cells containing a mutation at the hypoxanthine-guanine phosphoribosyl transferase (hprt) locus. Cells were plated in a selective medium, resulting in death of all unaltered parental A(9) cells. However, colonies of cells containing hypoxanthine phosphoribosyl transferase (EC 2.4.2.8) appeared with a variable frequency of about 10(-6) to 10(-7). The enzyme from these cells was indistinguishable from that from Chinese hamster cells, as shown by DEAE-cellulose chromatography and gel electrophoresis, and differed clearly from the mouse enzyme. The colonies, thus, did not result from reversion of A(9) parental cells to wild type, but appeared to represent progeny of individual cells that had ingested chromosomes, replicated, and expressed the hprt gene. These colonies differed from each other in stability of expression of the transferred gene.


A temperature-sensitive mutation affecting 28S ribosomal RNA production in mammalian cells. We have characterized a temperature-sensitive (ts) mutant of the hamster cell line BHK 21 that appears to have a defect in the processing of ribosomal RNA precursors at 39 degrees . Mutant ts 422E grows at a normal rate at 33 degrees , but upon shift to 39 degrees growth stops after about one cell doubling. The appearance of 28S rRNA and large ribosomal subunits in the cytoplasm of ts 422E at 39 degrees is inhibited by about 95%, when compared to wild-type BHK cells. Production of 18S rRNA and small ribosomal subunits is unaffected. Shift-up experiments show that the defect in 28S rRNA production can be detected as early as 2-3 hr after the shift to 39 degrees . Synthesis of the larger rRNA precursor is normal at high temperature, but the processing appears to be arrested after the formation of 32S rRNA. 32S rRNA accumulates to some extent in the nucleoli of ts 422E. ts 422E cells appear to have a single mutation, directly affecting the conversion of 32S to 28S rRNA. The reduced amount of 28S rRNA in the cytoplasm of ts 422E cells at 39 degrees seems therefore responsible for their inability to grow at this temperature.


Do cells cycle?

Do cells cycle? We propose that a cell's life is divided into two fundamentally different parts. Some time after mitosis all cells enter a state (A) in which their activity is not directed towards replication. A cell may remain in the A-state for any lenght of time, throughout which its probability of leaving A-state remains constant. On leaving A-state, cells enter B-phase in which their activities are deterministic, and directed towards replication. Initiation of cell replication processes is thus random, in the sense that radioactive decay is random. Cell population growth rates are determined by the probability with which cells leave the A-state, the duration of the B-phase, and the rate of cell death. Knowledge of these parameters permits precise calculation of the distribution of intermitotic times within populations, the behavior of synchronized cell cultures, and the shape of labeled mitosis curves.


"Recommended daily allowances" for vitamin C. Although 41 years have elapsed since the identification of vitamin C, the amounts required for human health are far from established. Pauling's suggestion that human needs for this vitamin probably have been underestimated by a factor of 10 or more has frequently been ignored or refuted by rhetoric rather than by sound experimentation. In the present study young healthy guinea pigs were fed a scrobutic diet supplemented with ascorbic acid at four widely different levels (0.05, 0.5, 5.0, and 50 mg/100 g of body weight per day). Growth rates both before and after surgical stress, recovery times after anesthesia, scab formation, wound healing, and the production of hydroxyproline and hydroxylysine during wound healing all support the conclusion that young guinea pigs ordinarily need about 5.0 mg/100 g of body weight daily. This is far beyond what is needed to prevent scurvy. Under stress the needs are even higher. On a body-weight basis this amount is equivalent to a need on the part of a 30-kg human child of 1500 mg of ascorbic acid daily. While calculations on a body-weight basis are subject to some uncertainty, the enormous discrepancy (nearly 40-fold) between this amount and that recommended by the Food and Nutrition Board calls attention to the extreme uncertainty about human ascorbic-acid needs, and to an important public health problem related to the best development of young people.


Deficient DNA repair in human progeroid cells. Skin fibroblasts biopsied from a patient with clinical symptoms of the Hutchinson-Gilford progeria syndrome failed to show evidence of normal DNA strand rejoining in vitro after exposure to cobalt-60 gamma irradiation. Control human diploid fibroblasts of fetal origin in early passage, skin fibroblasts of adult origin, and an established line of human liver cells (LICH) all showed essentially complete rejoining of radiation-induced strand breaks within 30 min after irradiation, as evidenced by DNA sedimentation profiles in alkaline sucrose gradients. The results suggest that an enzyme involved in DNA repair may be absent or greatly reduced in efficiency in cells from this patient with the progeria syndrome. Such a repair-deficient cell strain may prove useful in the study of the molecular events associated with x-ray-type damage and its repair in mammalian cells.


Membrane sealing in frog skeletal-muscle fibers. Self-sealing, not found in frog skeletal muscle fibers immersed in Ringer's solution, can be induced by solutions rich in calcium ion. Strontium replaced calcium on the sealing process, but magnesium did not. The sealing accomplished in high-calcium media was preserved in those fibers reimmersed in normal Ringer's solution. Measurements of the rate of sealing at different temperatures indicated that self-sealing induced by calcium has a high activation energy. Phospholipase C, an enzyme that hydrolyzes membrane phospholipids, produced a marked depression on the rate of sealing. Trypsin or chymotrypsin had no influence on the sealing process.


Value of Normotest and antithrombin 3 in the assessment of liver function.


Proposed molecular mechanism for the action of molybedenum in enzymes: coupled proton and electron transfer. The reactions catalyzed by Mo enzymes each find the product differing from the substrate by two electrons and two protons (or some multiple thereof). The coordination chemistry of Mo suggests that there is a distinct relationship between acid-base and redox properties of Mo complexes, and that a coupled electron-proton transfer (to or from substrate) may be mediated by Mo in enzymes. Each of the Mo enzymes (nitrogenase, nitrate reductase, xanthine oxidase, aldehyde oxidase, and sulfite oxidase) is discussed; it is shown that a simple molecular mechanism embodying coupled proton-electron transfer can explain many key experimental observations. In view of this mechanism, the reasons for the use of Mo (from an evolutionary and chemical point of view) are discussed and other metals that may replace Mo are considered.


Behaviour of antithrombin 3 in liver disease.


Coagulation factors as indicators of protein synthesis in chronic liver disease.


Significance and practicability of Normotest in diagnosis of chronic liver diseases.


Significance of intravascular coagulation and fibrinolysis in acute hepatic failure.


Statistical evaluation of Normotest in a longitudinal study of hepatitis.


Heparin therapy in the case of acute liver cirrhosis.


Normotest in acute viral hepatitis.

Normotest in acute viral hepatitis.


Study on the correlation between Normotest, Quick's method, and specific coagulation factors in liver disease.


Biochemical tests in evaluation of liver function.


Theory and experience behind the use of coagulation tests in diagnosis and prognosis of liver disease.


Coagulation abnormalities in acute liver failure; pathogenetic and therapeutic implications.


The diagnostic value of coagulation studies in chronic liver disease.


Normotest in acute hepatitis and chronic liver disease.


The relevance of blood clotting tests in chronic aggressive hepatitis.


Smear biopsy in neurosurgical diagnosis.


Study of the upper cervical spine by means of panoramic tomography.


Alveolar bone resorption after calcium deficiency in rats.


Effect of sitting posture on human body.


Synaptic integration and input-output relations in computer-simulated neuron.


Brain abscess. A clinical analysis of 26 cases with surgical treatment.


Multiple mycotic aneurysms of internal carotid arteries caused by osteomyelitis of skull. Report of a case.


Correlation among physical measures applicable in human engineering.


Dynamic study on cerebrospinal fluid circulation after subarachnoid hemorrhage.


Effect of combined administration of EACA and heparin on thrombus weight and fibrinolysis. An experimental study.


Tonsillectomy and adenoidectomy.

Tonsillectomy and adenoidectomy.


A new approach to state I of Crozat therapy.


A fixed-removable appliance for cuspid retraction.


Programs evaluated by the CDA Coucil on Hospital Services.


Your security.

Your security.


Maxillo-mandibular surgery for correction of dentofacial deformities: 4. Maxillary retrusion (mandibular pseudoprognathism).


Selection of patients amenable to simple orthodontic procedure using a Malocclusion Treatment Severity Index.


Scanning electron microscopy: observations on occlusal human dental plaque.


Use of sedation-analgesia in general dentistry.


Platelet metabolism in acute leukemia.

Platelet metabolism in acute leukemia.


Mandibular flexure in opening and closing movements.


Intravascular granulocyte kinetics and spleen size in patients with neutropenia and chronic splenomegaly.


Fabrication of temporary crowns and fixed partial dentures.


Principles of preparing endodontically treated teeth for dowel and core restorations.


Fracture strength of Class II amalgam restorations condensed over protective bases.


An amalgam and composite resin splint for posterior teeth.


Temporomandibular joint function and its effect on centric relation.


Evaluation of methods for polishing porcelain denture teeth.


Long-time observations of the Blalock-Taussig operation. V. Neoplasms in Tetralogy of Fallot.


Clonal origin of chronic myelocytic leukemia.


Ataxia-telangiectasia--clonal growth of translocation lymphocytes.


The failure of an autoclave.

The failure of an autoclave.


Fat necrosis. Studies in rats with experimentally induced pancreatitis.


Peripituitary gland involvement in acute leukemia in adults.


Medical writing.

Medical writing.


Sickle-cell problem.

Sickle-cell problem.


Liver injury by salicylates.

Liver injury by salicylates.


Problems confronting a dental society review committee.


DENTCAP: a personal recollection of dentistry in Vietnam.


A dental health project in Korea.

A dental health project in Korea.


Interactions involving drugs used in dental practice.


High blood pressure detection by dentists.


Evaluating the clinical quality of restorations.


Complaints regarding the use of dental materials and devices. Council on Dental Materials and Devices.


Doctor in the house.

Doctor in the house.


Possible caries prevention by fissure sealants.


Pulp reactions to a composite resin.

Pulp reactions to a composite resin.


A preliminary study of the disintegration of dental cements by continuous water spray.


Presence of fourth molars in a group of dental students.


Benign cementoblastoma in the maxilla.

Benign cementoblastoma in the maxilla.


Leukocyte purine phosphoribosyltransferases in human leukemias sensitive and resistant to 6-thiopurines.


Clinical and pharmacological studies with cis-diamminedichloroplatinum (II).


Philosophy of periodontal surgery.

Philosophy of periodontal surgery.


Safe use in dentistry: mercury.

Safe use in dentistry: mercury.


The preventive movement is strong.

The preventive movement is strong.


Report of a visit to the People's Republic of China. A Norwegian's diary.


Resolution of apical periodontal cysts.

Resolution of apical periodontal cysts.


Prevention of dental caries.

Prevention of dental caries.


The Case Western Reserve approach to teaching preventive dentistry.


Putting good nutrition into practice--your practice.


Dermatoglyphics in leukemia.

Dermatoglyphics in leukemia.


Dental manpower needs in the Republic of Ireland.


Malocclusion among Belfast School children.


Systemic mastocytosis.

Systemic mastocytosis.


Soluble proteins from human leukocyte granules. I. Esterase activity of cationic proteins.


Cutaneous lesions in disseminated mucormycosis.


Terminal nucleotide sequences of DNA from temperate coliphages.


Minute ring-shaped particles in cultured cells of malignant origin.


Influence of dietary jack beans (Canavalia ensiformis) and of concanavalin A on the growth of conventional and gnotobiotic Japanese quail (Coturnix coturnix japonica).


Importance of substrate variability to enzyme polymorphism.


Effects of diamorphine on various neurones in the rat central nervous system.


Tyrosyl peptide models for acidic protein-DNA interactions.


Non-enzymatic imidazole-catalysed acyl transfer reaction and acetylcholine synthesis.


Muramidase activity in leukemia and myeloproliferative disorders.


The immobilization period for fractures of the mandibular body.


The technical aspects of electrosurgery.


Definitive treatment of mandibular fractures in young children.


Interference with the function of the inferior dental nerve by a root fragment. Report of a case.


Effect of tongue brushing on plaque bacteria.


Experimental follicular cysts in mice. A histologic study.


Homocystinuria: a differential diagnosis of Marfan's syndrome.


Taurodontism, diminished root formation, and microcephalic dwarfism.


Unusual multilocular cysts of the jaws (botryoid odontogenic cysts).


Ectopic cartilage in thyroid.

Ectopic cartilage in thyroid.


Cutting efficiency of endodontic reamers.


Roentgenographic investigation of the mesiobuccal root of the maxillary first molar.


A histopathologic evaluation of tissue reactions to the minimum effective doses of some endodontic drugs.


A comparative study of long-cone and short-cone bitewing radiographs.


Evaluation of film processing with concentrated solutions.


Bifid inferior alveolar canal.

Bifid inferior alveolar canal.


Unusual foreign body.

Unusual foreign body.


Bilateral head-on impactions.

Bilateral head-on impactions.


Rhinolith.

Rhinolith.


Localization of the placental site with chromium 51 -tagged erythrocytes.


A comparative study of in-hospital practice in Rhode Island.


Scleredema Vs. scleroderma. Differentiation of often confused disorders is explained.


A mechanical appraisal of the Kloehn extraoral assembly.


The soft tissue profile in unilateral clefts.


Postretention status of maxillary incisors with root-end resorption.


Development and eruption of the mandibular third molar and its response to orthodontic therapy.


A longitudinal cephalometric study of incisor overbite from ages five to eleven.


Pure Begg and edgewise arch treatments: comparison of results.


The facial configuration in a sample of Chinese boys.


Growth of the mandible relative to a cranial base line.


The hereditary components of mandibular growth, a longitudinal twin study.


A cephalometric study of profile changes in orthodontically treated cases ten years out of retention.


Contributions of the posterior cranial base and mandibular condyles to facial depth and height during puberty.


Procedural factors that affect the success of microbial insecticides. Industrialization.


Regulation of microbial pesticides.

Regulation of microbial pesticides.


Regulation of insect populations by microorganisms. V. Establishing priorities. Toward abundance and good environment.


Information flow, interpretation, psychoanalysis: epistemological reflexions.


Psychiatric admissions and climatic factors in the coastal regions of Israel.


Crime and delinquency among aged in Israel. An experience survey.


Taboo, projection, and magical thinking.


Reactions of three schizophrenic patients to their brother's death.


The circumcision ceremony among immigrants from Tripolitania in the Israeli village of Dalton.


Arejuvenated hope--The New York Dental Service Corporation.


Dental education.

Dental education.


A need for all views within the dental profession.


Lipoma of the tongue. Case report.

Lipoma of the tongue. Case report.


Supernumerary mandibular bicuspid. Report of a case.


Broken instruments in root canals.

Broken instruments in root canals.


Stimulus intensity and foreperiod effects in intersensory facilitation.


Temporal characteristics in apparent movement: omega movement vs. phi movement.


Input-output relations in simple reaction time experiments.


Osseous tumors of the orbit.

Osseous tumors of the orbit.


The relation between physical stimulus properties and the effect of foreperiod duration on reaction time.


Learning 10,000 pictures.

Learning 10,000 pictures.


Effects of S-R and R-R compatibility on bimanual movement time.


Learning rhythmic hand movements.

Learning rhythmic hand movements.


Variations in size judgements as a function of surface texture.


Semantic representation of shape names.

Semantic representation of shape names.


Preserve this house of medicine.

Preserve this house of medicine.


Geographical patterns of infant mortality in West Virginia.


[Cholinergic innervation of the normal gingiva and its changes in chronic marginal parodontitis].


"Preleukemia". A myelodysplastic syndrome often terminating in acute leukemia.


Management of acute leukemia in children.


The dental profession and unions.

The dental profession and unions.


Dental unions--our Trojan horse.

Dental unions--our Trojan horse.


A dental examiner's view of dental education.


An increased measure of social consciousness.


The relationship between social class academic achievement and National Board scores of students in a dental school.


Action of fluoride on salivary lysozyme.


Effects of the tonic neck reflex on the jaw muscles of the rat.


Effects of dextranase from Spicaria violaceae (IFO 6120) on the polysaccharides produced by oral streptococci and on human dental plaque.


Effect of phosphate and pH on Streptococcus mutans acid production and growth.


Comparison of the strength of barnacle and commercial dental cements.


Correlation study of incisive biting forces with age, sex, and anterior occlusion.


Ultrastructure of human enamel specimens prepared by ion micromilling.


Quantitative measure of mercury vapor emission from setting dental amalgam.


Effect of undernutrition during the perinatal period on caries development in the rat. 11. Caries susceptibility in underfed rats supplemented with protein or caloric additions during the suckling period.


Effect of undernutrition during the perinatal period on caries development in the rat. 3. Effects of undernutrition on biochemical parameters in the developing submandibular salivary gland.


Elasticity of elastometer impression materials. 11. Permanent deformation.


Effect of undernutrition during the perinatal period on caries development in the rat. IV. Effects of differential tooth eruption and exposure to a cariogenic diet on subsequent dental caries incidence.


A new dental superalloy system. IV. X-ray diffraction analysis.


Empirical equation for estimating the area of a maxillary edentulous jaw.


Periodontal disease and oral hygiene in an Alaskan Eskimo population.


Determinants of variations in the supply and distribution of dental manpower among metropolitan areas.


Effect of the contraceptive steroids norethynodrel and mestranol on dental caries activity in young adult female rats.


Use of a chain binomial in the epidemiology of caries.


Oxytalan fiber system of molars in the mouse mandible.


Dextranglucosidase activity in supragingival plaque.


Nicotine stomatitis and its relation to carcinoma of the hard palate in reverse smokers of chuttas.


Movements of the jaw after unexpected contact with a hard object.


Isolation and characterization of beta-N-acetylglucosaminidase from human parotid saliva.


Anticoagulant resistance in wild Norway rats in New York. Wild Norway rats (Rattus norvegicus) from several habitats were tested for their susceptibility and resistance to warfarin. Animals were fed 0.005% warfarin in ground oatmeal for periods varying from 1 to 12 days. Rats having no prior exposure to anticoagulants were shown to be susceptible, none having survived a 6-day feeding period. Resistant rats were found on two farms where anticoagulant materials had been used intensively for about 20 years.


Studies on the biology of the periodontium of marmosets. XI. Histopathologic manifestations of spontaneous and induced vitamin A deficiency in the oral structures of adult marmosets.


Study of the electrochemical behavior of gold dental alloys.


Buccal commissurectomy in miniature swine.


Effect of dietary factors on cesium 137 retention in the rat.


Marginal fracture of amalgam restorations.


Influence of riboflavin on fluoride metabolism in the rat.


Examination of two bacterial strains designated "Brucella suis biotype 5". The morphological, cultural, biochemical, serological and pathogenic properties of two bacterial strains of the group designated ;Br. suis biotype 5' were examined. Both strains were found to be atypical of the genus Brucella in many of these characteristics. No serological relationship to known brucella strains could be detected. On the basis of the evidence obtained the two strains examined were classified as Moraxella duplex and the status of ;Br. suis biotype 5' questioned.


Aminoadamantane-resistant strains of influenza A2 virus. After one passage of influenza A2/Singapore/1/57 virus in mice treated with 150 mg./kg./day of aminoadamantane, a partially drug-resistant strain of virus was detected in 1 of 12 mice. The isolation rate of aminoadamantane-resistant viruses increased to 8 after three passages in drug-treated mice. Some virus strains showed a 500-fold increase in resistance to aminoadamantane and to the structurally related compounds alpha-methyl-1-adamantane methylamine and 2-adamantanamine sulphate. No aminoadamantane-resistant viruses were detected after passage of influenza four times in mice treated with lower (15 or 1.5 mg./kg./day) concentrations of aminoadamantane. Aminoadamantane had no detectable effect on the development of lung lesions in mice infected with the drug-resistant influenza strain, whereas lung lesions were reduced in aminoadamantane treated mice infected with a control strain of influenza A2/Singapore virus. No differences were detected in the buoyant density in caesium chloride, morphology or serology between control and aminoadamantane-resistant strains of virus. These drug-resistant influenza viruses may be useful for detailed studies of the mode of action of aminoadamantane.


Reactions to tetanus toxoid.

Reactions to tetanus toxoid. In a factory population the occurrence of reactions to tetanus toxoid was recorded after 6740 injections. The incidence of general reactions was 0.3% and of local reactions 2.6%. The local reaction rate to the first injection of the basic immunization course was 0.9%, to the second injection 2.7%, and to the third injection 7.4%. To booster injections the rate was 1.6%. The local reaction rate was appreciably higher in women than in men - 14.4% and 5.7% respectively in the case of the third injection - and the incidence among women increased with age.Tetanus vaccine containing 10 Lf of toxoid caused fewer reactions than one containing 20 Lf, but a reduction in the content of aluminium adjuvant did not affect the reaction rate.Almost all reactors were found to have a satisfactory serum antitoxin concentration at the time of the reaction or developed a satisfactory immunity within 1-6 months.Skin tests were made in 32 hypersensitive patients. Neither the diluent, thiomersal preservative, nor the culture medium appeared to be responsible for hypersensitivity. The degree of hypersensitivity elicited by a special highly purified toxoid was only very slightly less than that elicited by the commercially pure toxoid. It is suggested that reactions are largely due to the toxoid antigen itself rather than to impurities or other components of the vaccine.


Mortality from cancer and cardiovascular diseases in the county boroughs of England and Wales classified according to the sources and hardness of their water supplies, 1958-1967. Relative rates of proportionate mortality from cancer of six sites based on total cancer deaths and the proportions expected in all towns, and from four types of cardiovascular disease based on total deaths from all causes, have been related in the 80 county boroughs of England and Wales to the sources of water supply and to the average hardness of water in the towns. The sources of water, from upland surfaces, artesian wells and rivers, were classified in eight groups, and significant associations were found for cancers of the stomach, oesophagus, prostate, male bladder and female breast, and for hypertensive and chronic rheumatic heart disease. No associations were apparent with intestinal cancer, vascular disease of the nervous system or arteriosclerotic heart disease. Hardness or softness of the water was classified in seven groups and significant associations were found for the same diseases as for source of water, none being evident for coronary disease.


Age, time and cohort factors in mortality from cancer of the cervix. Data for mortality from cancer of the cervix in England and Wales by 5-year age groups and four quinquennia (1951-70) are analysed. The logarithms of the mortality rates are regressed on age group, epoch of death and epoch of birth. The factors obtained are considered in relation to particular features of the mortality pattern, such as the reversal of trend in certain age groups.


Submerged deciduous molars and congenital absence of premolars.


Training of surgical researchers: head and neck--an NIDR workshop.


Macquarie Island: the introduction of the European rabbit flea Spilopsyllus cuniculi (Dale) as a possible vector for myxomatosis. The European rabbit flea Spilopsyllus cuniculi (Dale) was first released on Macquarie Island in December 1968. The flea has survived and bred on the island and about 30% of the rabbits sampled from the original release area in January 1972 were flea-infested.


The evidence for the airborne spread of Newcastle disease. Newcastle disease virus has been shown to survive when airborne in small particles, both in the laboratory and in the open air. Field outbreaks have been studied and viable virus has been recovered from the open air short distances downwind of infected premises. Vaccination of birds leads to a great reduction in the amount of virus liberated into the air.


X-ray diffraction analysis of Cu6Sn5 formation during setting of dental amalgam.


Hydrolysis of glycol chitin by an endo-and exo-type of beta-N-acetylglucosaminidase from human parotid saliva.


An ultrastructural study of ropalocytosis in human blood and bone marrow.


Staphylococcal infection in an intensive-care unit, and its relation to infection in the remainder of the hospital. A survey of the staphylococcal infections occurring in a general hospital over a period of four and a half years showed that multiple-resistant strains of phage type 77 were endemic in the medical and surgical wards. Strains of this phage type were uncommon among patients attending the casualty department, and those found were usually either fully sensitive to antibiotics or resistant to benzylpenicillin only. Regular monitoring of patients admitted to the intensive-care unit showed that 58% of staphylococcal infections in such patients were present at the time of admission to the unit. Although the wards thus constituted a significant reservoir of infection for the intensive-care unit, there was no evidence to suggest that the return of patients from the unit to the wards was responsible for the transfer of infection in the opposite direction. The possibility of reducing the numbers of multiple-resistant staphylococci in the general wards, by the screening of all new admissions for the presence of tetracycline-resistant strains, appears to be impracticable in this area.


Extraction of first molars in discrepancy cases.


Expanded use of auxiliary personnel in orthodontic practice.


Crown-root angles of upper central incisors.


Selection of predictor variables in assessing the severity of malocclusion.


Variability of the craniofacial skeleton. An exercise in roentgen-cephalometry.


President's page.

President's page.


American Board of Orthodontics sets new standards and requirements.


AAO Board and House determine new Association policies.


A vector analysis of the straight begg arch wire throughout stages I and II in the mandible.


The value of the PM vertical reference line to estimate natural head position.


Topical application of thyrocalcitonin in the jaws of laboratory dogs.


Pulmonary blastoma, report of a case.

Pulmonary blastoma, report of a case.


Giant cysts of the popliteal fossa and calf in rheumatoid arthritis.


X-ray film of the month. Hilar adenopathy.


Isolation of the operators of phage lambda.


Human care.

Human care.


Adaptive significance of alcohol dehydrogenase isozymes in maize.


New look at antiserum therapy of leukaemia.


Testosterone concentrating mechanism in the reproductive organs of the male rat.


Delayed methylation of DNA in developing sea urchin embryos.


Streptomycin-resistant plants from callus culture of haploid tobacco.


Translocation of C from Festuca plants to their endomycorrhizal fungi.


Chemotherapy for an elective effect on mammalian tumour cells.


Expression of lambda plac5 DNA in cultured cells of a higher plant.


Human antigen for the Paul-Bunnell antibody.


Chromosomal interchanges induced by radiation in spermatogonial cells and leukocytes of mouse and Chinese hamster.


Failure to produce cell-free lymphotoxin.


A new class of synthetic nucleoside analogues with broad-spectrum antiviral properties.


Neurohypophysial hormones and evolution of tetrapods.


Reversible abolition of normal morphology in Hydra.


Vulpia sicula and the genus Vulpia.

Vulpia sicula and the genus Vulpia.


Structures for Poly(U)-poly(A)-poly(U)triple stranded polynucleotides.


Genetic fusion of incompatible plasmids in Pseudomonas. The genes specifying enzymes responsible for the degradation of camphor and octane occur on transmissible plasmids in Pseudomonas putida strain PpG1 and P. oleovorans. Since the presence of the plasmids is vital for the oxidative metabolism of camphor or octane (by the cells) in the absence of other carbon sources, such naturally occurring, energy-generating plasmids have been designated as degradative plasmids. The two degradative plasmids, CAM and OCT, are incompatible with each other and cannot coexist in the same cell. By the use of UV irradiation and suitable selection techniques, it has been possible to fuse these two plasmids so they become part of the same replicon and coexist. Such a technique might be useful in introducing several degradative pathways in the same cell.


Bacteriophage T4 head morphogenesis. Isolation, partial characterization, and fate of gene 21-defective tau-particles. A lysozyme-detergent procedure was developed for isolation of tau-particles from cells infected by gene-21 mutants of T4 bacteriophage. These particles have a sedimentation coefficient of 440 +/- 10 S. They contain less than 1% detectable nuclease-resistant DNA, are smaller (650 x 850 A) than normal bacteriophage heads (800 x 1100 A), and exhibit two major bands on 7.5% Na dodecyl sulfate-acrylamide gels. The more prominent band (55,000 daltons) corresponds to the uncleaved, major capsid polypeptide (P23); the other band (32,000 daltons) corresponds to the gene-22 product (P22). Temperature-shift experiments with cells infected with tsN8 (gene 21) mutants were used to study the fate of tau-particles accumulated under nonpermissive conditions. 50 Min after ts N8-infected cells were shifted from the nonpermissive (41.5 degrees ) to the permissive (25 degrees ) temperature, a phage burst occurred that was 75% of that observed with wild-type phage. However, in "pulse-chase" temperature-shift experiments, the radioactive tau-particle peak only slightly decreased (by 10-14%) by 50 min after the shift, whereas an increased amount of radioactivity (about four times as much as the tau-particle decrease) appeared in phage particles. The results suggest that at least two pools of head polypeptides coexist in cells infected with gene-21 mutants. One pool is composed of head subunits assembled into tau-particles, which are mostly aberrant structures; the second pool is composed of head subunits that are incorporated into mature phage when the gene-21 product becomes functional.


Change in cell-surface glycoproteins of mouse embryos before implantation. The early biochemical ontogeny of the mammalian cell surface has been examined in mouse embryos. After in vitro incubation of embryos in D-[(3)H]- or D-[(14)C]glucosamine, the cell-surface glycopeptides were removed by trypsinization, digested with Pronase, and fractionated by gel filtration on Sephadex G-50; radioactivity was determined in the fractions by scintillation counting. Cochromatography of digests from the surfaces of embryos of two age groups yielded markedly different elution patterns. The labeled surface material from embryos in or near the blastocyst stage, when the outermost cells are differentiating into trophoblast, was substantially enriched, as compared with material from cleavage-stage embryos, in relatively more rapidly eluted components of presumed higher molecular weight. A similar change has previously been reported by others in cultured mammalian cell lines after viral transformation, in comparison with corresponding untransformed cells. This similarity between blastocysts and transformed cells suggests that the early biochemical differentiation of the surface, as the embryo passes into the blastocyst stage, may be responsible for the stage-specific capacity of the outermost cells to attach to the uterine wall in response to an implantation-initiating stimulus and to become invasive.


Glycopeptides from surface membranes of neuroblastoma cells. Sequential removal of surface glycopeptides was achieved by subjection of mouse neuroblastoma cells to a two-step trypsin treatment under different conditions. The glycopetides released by each trypsinization step were digested by Pronase and examined on columns of Sephadex G-50. Different chromatographic patterns were found for the two digests. Thus, several groups of glycopeptides can be distinguished by the trypsinization procedure. One group is readily removed and appears to be at a more accessible location on the cell surface. Among the four neuroblastoma clones examined, the glycopeptide patterns from axon-forming cells differed from those of axon-minus cells.


Control of pineal indole biosynthesis by changes in sympathetic tone caused by factors other than environmental lighting. The melatonin (5-methoxy-N-acetylserotonin) content and N-acetyltransferase activity of rat pineal increase rapidly in response to physical immobilization or insulin-induced hypoglycemia. Carbohydrate consumption, which causes insulin release without hypoglycemia, does not elicit these pineal responses. Prior treatment with propranolol, a beta-adrenergic blocking agent, inhibits the N-acetyltransferase responses to hypoglycemia and immobilization, indicating that these changes result from stimulation of pineal beta-receptors by a catecholamine, presumably norepinephrine released from pineal sympathetic nerve terminals. Prior destruction of those terminals with 6-hydroxydopamine does not block, but actually potentiates, the increase in melatonin content and N-acetyltransferase activity after induced hypoglycemia or immobilization. This finding probably reflects an action of circulating catecholamines, secreted from the adrenal medullae or surviving sympathetic nerve terminals, on supersensitive pineal cells. These observations indicate that factors other than changes in environmental lighting, which modify sympathetic nervous tone, can also influence pineal function.


Oxygen equilibrium and kinetics of isolated subunits from hemoglobin Kansas. The isolated beta subunit of hemoglobin Kansas has an oxygen affinity that is as low relative to the oxygen affinity of the beta(A) subunit as the affinity of hemoglobin Kansas is low relative to hemoglobin A. Thus the low affinity properties of hemoglobin Kansas are almost completely reflected in the properties of the isolated subunits. The kinetic results show that the equilibrium affinity difference results both from a much larger oxygen dissocation rate constant in beta(Kansas) (k = 37 sec(-1) and 18 sec(-1) for beta(Kansas) and beta(A), respectively) and from a lower association reaction rate, The properties of the alpha chains from hemoglobins A and Kansas appear to be identical, as expected.


Effects of a snake alpha-neurotoxin on the development of innervated skeletal muscles in chick embryo. The evolution of the cholinergic (nicotinic) receptor in chick muscles is monitored during embryonic development with a tritiated alpha-neurotoxin from Naja nigricollis and compared with the appearance of acetylcholinesterase. The specific activity of these two proteins reaches a maximum around the 12th day of incubation. By contrast, choline acetyltransferase reaches an early maximum of specific activity around the 7th day of development, and later continuously increases until hatching. Injection of alpha-toxin in the yolk sac at early stages of development causes an atrophy of skeletal and extrinsic ocular-muscles and of their innervation. In 16-day embryos treated by the alpha-toxin, the endplates revealed by the Koelle reaction are almost completely absent. The total content and specific activities of acetylcholinesterase and choline acetyltransferase in atrophic muscles are markedly reduced.


Biogenesis of poxviruses: inactivation of host DNA polymerase by a component of the invading inoculum particle. Inhibition of nuclear DNA polymerase activity in cells infected with vaccinia virus parallels the development of a nuclease activity similar to one associated with the virus particles. Both phenomena occur in the absence of protein synthesis, implying that incoming particles are responsible for the effects observed. Experimental evidence is presented indicating that the nuclear DNA polymerase activity is inhibited coincidentally with, and perhaps as a consequence of, the hydrolysis of nascent, single-stranded DNA molecules. Should this interpretation prove to be correct, our observations may have revealed the first instance in virus cytopathology linking the inactivation of a specific host-cell function with an enzyme activity originating from the invading particle.


Hemogloblin switching in sheep and goats: erythropoietin-dependent synthesis of hemoglobin C in goat bone-marrow cultures. The anemia-induced switch from hemoglobin A (alpha(2)beta(2) (A)) to hemoglobin C (alpha(2)beta(2) (C)) synthesis occurring in vivo in sheep and goats has been reproduced in tissue culture of goat bone-marrow cells. Cultivation of primary cultures of goat bone marrow in the presence of erythropoietin results in the appearance of detectable amounts of beta(C) globin after 48-72 hr, as well as in a decrease in beta(A) globin. A population of proerythroblasts, as well as active heme and globin synthesis, are maintained for at least 3 days in erythropoietin-treated, but not in erythropoietin-deficient, cultures. These findings demonstrate (i) maintenance of erythropoietin-responsive cells from bone marrow in vitro, and (ii) switching in vitro from the synthesis of a globin chain coded by one gene to that coded by a different, nonallelic gene. Bone-marrow culture might be a useful model system for study of the mechanism of action of erythropoietin and for study of the activation (and inactivation) of specific genes in vitro.


Ca2+ transport by mitochondria from L1210 mouse ascites tumor cells. Mitochondria isolated from the ascites form of L1210 mouse leukemia cells readily accumulate Ca(2+) from the suspending medium and eject H(+) during oxidation of succinate in the presence of phosphate and Mg(2+), with normal stoichiometry between Ca(2+) uptake and electron transport. Ca(2+) loads up to 1600 ng-atoms per mg of protein are attained. As is the case in mitochondria from normal tissues, Ca(2+) uptake takes precedence over oxidative phosphorylation. However, Ca(2+) transport by the L-1210 mitochondria is unusual in other respects, which may possibly have general significance in tumor cells. The apparent affinity of the L1210 mitochondria for Ca(2+) in stimulation of oxygen uptake is about 3-fold greater than in normal liver mitochondria; moreover, the maximal rate of Ca(2+) transport is also considerably higher. Furthermore, when Ca(2+) pulses are added to L1210 mitochondria in the absence of phosphate or other permeant anions, much larger amounts of Ca(2+) are bound and H(+) ejected per atom of oxygen consumed than in the presence of phosphate; up to 7 Ca(2+) ions are bound per pair of electrons passing each energy-conserving site of the electron-transport chain. Such "superstoichiometry" of Ca(2+) uptake can be accounted for by two distinct types of respiration-dependent interaction of Ca(2+) with the L1210 mitochondria. One is the stimulation of oxygen consumption, which is achieved by relatively low concentrations of Ca(2+) (K(m) congruent with 8 muM) and is accompanied by binding of Ca(2+) up to 40 ng-atoms per mg of protein. The second process, also dependent on electron transport, is the binding of further Ca(2+) from the medium in exchange with previously stored membrane-bound protons, in which the affinity for Ca(2+) is much lower (K(m) congruent with 120 muM).


Evidence for a monoclonal origin of human atherosclerotic plaques. The main cellular elements of atherosclerotic plaques are smooth muscle cells. Because these plaques differ from their precursors in the underlying artery wall in several ways, we have asked the question: Are human atherosclerotic plaques polyclonal or monoclonal in their origin? The X-linked glucose-6-phosphate dehydrogenase (EC 1.1.1.49) in heterozygotic females has been used to obtain an answer. 30 Plaques of different degrees of complexity and 59 samples of normal aorta and iliac artery walls from four females, 25-79 years old, were investigated. The data show that fibrous caps even of relatively large atheromatous plaques, 0.5 cm or greater in diameter, are composed of cells that produce solely or predominantly one enzyme type, whereas samples of artery wall media and intima as small as 0.1 mm(3) are regularly composed of a mixture of cell types. If plaques were a response to injury akin to a healing wound, a reaction to a growth stimulant, or formed due to an organization of a mural thrombus, they would be expected to be polyclonal. Hence, the results imply that atherosclerotic plaques in human beings arise by another mechanism. The mechanism compatible with the monoclonal nature of atherosclerotic plaques is mutation, and the likely causes are chemical mutagens or viruses.


Origin and direction of replication of bacteriophage 186 DNA. Intracellular bacteriophage 186 DNA replicates as a single-branched circle during the first round of replication. The free end of the branch is located at a unique position with respect to phage 186 DNA base sequence, and this point should, therefore, correspond to the origin of DNA replication. The position of the growing point has been mapped at various degrees of replication, and found to move unidirectionally from left to right with respect to the denaturation map of phage 186 DNA.A small proportion of the replicating molecules have two linear branches connected to the circle at two different branch points. These structures are consistent with two separate initiations from the same origin, again, with a unidirectional mode of replication. Branch points frequently have a single-stranded connection between the circle and the branch; significant numbers of branch points also possess an extra short single-stranded "whisker" protruding out of the branch point.


The genetic system in parthenogenetic strains of Drosophila mercatorum. Five parthenogenetic laboratory strains of Drosophila mercatorum have been examined for their mode of diploidization in the eggs of females. Diploidization occurs either by pronuclear duplication leading to complete homozygosity or by nuclear fusion. If the latter occurs between pronuclei from different secondary oocytes, heterozygosity can be maintained. Each of the five strains shows some nuclear fusion and three show significantly different amounts, ranging from about 21% to less than 1%. Even in strains with a strong tendency towards homozygosity, it is argued that this dual system of nuclear reconstitution provides for genetic recombination; thus, the strains retain considerable evolutionary potential.


Evidence of inter-organ amino-acid transport by blood cells in humans. To evaluate the contribution of blood cellular elements to inter-organ transport of amino acids, net exchange across the leg and splanchnic bed of 17 amino acids was determined in seven healthy postabsorptive subjects by use of both whole blood and plasma for analysis. Arterial-portal venous differences were measured in five additional subjects undergoing elective cholecystectomy. By use of whole blood, significant net release of amino acids was noted from the leg and gut, while a consistent uptake was observed by the splanchnic bed. The output of alanine from the leg and gut and the uptake of this amino acid by the splanchnic bed exceeded that of all other amino acids and accounted for 35-40% of total amino-acid exchange. Transport by way of plasma could not account for total tissue release or uptake of alanine, threonine, serine, glutamine, methionine, leucine, isoleucine, tyrosine, and citrulline. For each of these amino acids, significant tissue exchange was calculated to occur by way of the blood cellular elements, the direction of which generally paralleled the net shifts occurring in plasma. For alanine, 30% of its output from the leg and gut and 22% of its uptake by the splanchnic area occurred by way of blood cells. We conclude that the blood cellular elements, presumably erythrocytes, contribute substantially to the net flux of amino acids from muscle and gut to liver in normal postabsorptive humans. Alanine predominates in the inter-organ transfer of amino acids occurring by way of blood cells as well as plasma.


Electron density map as an aid in the sequencing of peptides.


Aminoacid sequence of dogfish M4 lactate dehydrogenase. About 80% of the aminoacid sequence of dogfish (Squalus acanthius) M(4) lactate dehydrogenase (EC 1.1.1.27) has been elucidated. Several sequence homologies with peptides from pig H(4) and pig M(4) lactate dehydrogenase are identified. Histidine 195 is homologous to the essential histidine residue in pig H(4) lactate dehydrogenase. Similarities in the sequence around the "essential" cysteine residue of lactate dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase, and yeast and liver alcohol dehydrogenase are delineated.


Development of auditory neuronal responses in avian embryos. Neurons in the cochlear nuclei of duck embryos become responsive to tonal stimuli in an orderly spatial and temporal sequence. Cells responding to lower frequencies are recorded before those responding to higher frequencies. Auditory neurons are spatially arranged according to their characteristic frequencies, indicating a point-by-point projection of the basilar membrane. Areas of the nuclei where the apical segment of the basilar membrane projects become responsive to sound before regions representing more basal segments. These progressive changes with age are accompanied by a gradual rise both in neuronal sensitivity and in frequency range of maximum sensitivity. The development of auditory neural responses is timed to prepare the embryo for the onset of prenatal mother-young communication.


Translation of brome mosaic viral ribonucleic acid in a cell-free system derived from wheat embryo. The four RNAs of brome mosaic virus induce substantial incorporation of amino acids into protein when used as messengers in a cell-free protein-synthesizing system derived from wheat embryo. RNA 4 is highly efficient as a monocistronic messenger for the viral coat protein. Acetate, derived from acetyl coenzyme A, is incorporated into the product made in vitro. Although RNA 3 also contains the coat-protein cistron, it induces synthesis mostly of a protein larger than coat protein. RNAs 1 and 2 also induce the synthesis of substantial amounts of protein other than coat protein. However, an equimolar mixture of RNAs 3 and 4 or of 1, 2, 3, and 4 induces synthesis of coat protein almost exclusively. This result suggests that the coat-protein cistron, when present as a monocistronic messenger, inhibits translation of all other viral messages.