Responses of serum luteinizing hormone and follicle-stimulating hormone levels to synthetic luteinizing hormone-releasing hormone (LH-RH) in various forms of testicular disorders.


The half-life, metabolism and excretion of tritiated luteinizing hormone-releasing hormone (LH-RH) in man.


Growth and development of children with renal transplants. Use of alternate-day steroid therapy.


Burn-wound management.

Burn-wound management.


Pernicious anemia with persistent malabsorption of vitamin B12 in a child.


Letter: Pacifist factors in human milk?

Letter: Pacifist factors in human milk?


Bibliography of the literature on antibiotics published in foreign countries. 98.


Management of spina bifida cystica. Part 1: clinical types of spina bifida.


Pituitary FSH and LH reserve in women with isolated gonadotropin deficiency.


Correction of prolapsed vagina or enterocele with fascia lata.


A clinical study of lactation suppression.


Combination radiotherapy and chemotherapy in the treatment of early Hodgkin's disease.


The role of the liaison psychiatrist in a hemodialysis program: a case study.


The effect of alcohol on intracranially reinforced response.


Medium-sized computers: bringing computers into the lab.


Tiotixene and thioridazine in alcoholism treatment.


Carl Reyher (1846-1890), great Russian military surgeon: His demonstration of the role of debridement in gunshot wounds and fractures.


A technique for autografting very large burns from very limited donor sites.


Biographical sketch of Dr. Albert J. Ochsner.


Henry Claris Sweany.

Henry Claris Sweany.


Repeated neck exploration in primary hyperparathyroidism: localization of abnormal glands by selective thyroid arteriography, selective venous sampling, and radioimmunoassay.


Functions of baseplate components in bacteriophage T4 infection. II. Products of genes 5, 6, 7, 8, and 10.


Louis N. Katz.

Louis N. Katz.


Herbert F. Binswanger.

Herbert F. Binswanger.


An extended phage growth cycle in T4 infected A. aerogenes.


Robert Wartenberg--heritage of neurology.


Louis Scheman.

Louis Scheman.


Unique forms of fast-sedimenting BU lambda DNA in a superinfected E. coli lysogen.


Electron microscopic denaturation map of bacteriophage 186 DNA.


Structural proteins of coliphage N4.

Structural proteins of coliphage N4.


Repair of gamma-ray-induced damage in bacteriophage lambda.


Propranolol-bunolol and phencarbamide in chloroform-induced ventricular fibrillation in mice.


Clinical examination of drugs, a scientific and ethical challenge.


Are controlled clinical trials unnecessary?


Psychiatric practice in Canada pre- and post-medicare.


Studies of the immunological capacity of germ-free mouse radiation chimeras. I. Chimerism and humoral immune response.


Studies of the immunological capacity of germ-free mouse radiation chimeras. II. Thymus cell function in a humoral immune response to sheep erythrocytes.


Expression of cell surface markers on T and B lymphocytes after long-term chemotherapy of acute leukemia.


Arterial repair and atherosclerosis after mechanical injury. 5. Tissue response after induction of a large superficial transverse injury.


Differential effects of concanavalin A on T helper dependent and independent antibody responses.


Tumor detection in radiographs.

Tumor detection in radiographs.


A method of computer-assisted pacemaker surveillance from a patient's home via telephone.


Computer processing of ultrasonic data from the cardiovascular system.


Computer interpretation of ventilatory studies.


Probabilistic information processing: implementation and evaluation of a Semi-PIP diagnostic system.


An experimental model of autoimmune hemolytic anemia in mice.


Interactions of aspirin with nonsteroidal antiinflammatory drugs in man.


Modeling techniques for medical diagnosis. I. Heuristics and learning programs in selected neonatal hepatic disease.


Antithymocyte serum treatment of hamsters inoculated with a measles virus isolated from a patient with subacute sclerosing panencephalitis.


In vitro immune response to lipopolysaccharide: thymus-derived cells not required.


Prevention of experimentally induced enteric colibacillosis in newborn calves. Severe enteric colibacillosis, characterized by profuse watery diarrhea, dehydration, apathy, hypothermia, and inability to stand, was produced in seven of eight newborn, colostrum-fed calves from nonvaccinated dams after oral challenge of calves with 10(11) viable cells of Escherichia coli strain B44. Twenty-nine of 32 calves from dams vaccinated with various preparations of E. coli strain B44 were protected against severe enteric colibacillosis after oral challenge. Calves were protected if the dams received two subcutaneous vaccinations prior to calving. Calves also were protected if the dams were given a homologous vaccine of live or killed whole cells or a broth culture supernatant vaccine via the subcutaneous and intramammary routes 1 year earlier. Nineteen of the 29 protected calves had a transient diarrhea.


Inhibition by oxisuran of cell-mediated hypersensitivity by decrease in numbers of specifically sensitized cells. Oxisuran, 2-([methylsulfinyl]acetyl)pyridine, has previously been shown to selectively suppress cell-mediated immunity, as measured by prolongation of allograft survival, without inhibition of humoral immunity. In the present investigation, the influence of this compound on lymphoid cell transfer of delayed hypersensitivity was studied. In actively sensitized animals, including endotoxin-sensitized mice and rabbits, ovalbumin-, dinitrochlorobenzene-, and dinitrofluorobenzene-sensitive guinea pigs, or tuberculin-sensitive rats, daily treatment during the interval just preceding the elicitation and expression of the hypersensitivity was most inhibitory. In both endotoxin-sensitive mice and ovalbumin-sensitive guinea pigs, treatment of the sensitized cell donor just prior to lymphoid cell harvest and transfer resulted in inhibition of the expression of the hypersensitivity in untreated recipients. Approximately 10(4) fewer specifically sensitized lymphoid cells, but not fewer viable cells, were present in passively transferred cell preparations. In contrast, treatment of the lymphoid cell recipient in the same experimental model did not influence the expression of the transferred hypersensitivity. The results suggest that oxisuran may influence an as yet undefined event prior to the expression of a cell-mediated hypersensitivity response in sensitized animals.


Mechanism of adherence of Streptococcus mutans to smooth surfaces. I. Roles of insoluble dextran-levan synthetase enzymes and cell wall polysaccharide antigen in plaque formation. The mechanism of adherence of Streptococcus mutans to smooth glass surfaces has been studied. The results with both viable and heat-killed cells showed that the process required (i) the synthesis of a water-insoluble dextran-levan polymer by cell-bound enzymes and (ii) the participation of a binding site on the surface of the S. mutans cell. Synthesis of the polymer from sucrose in the presence of the cells was required for adherence, and indicates that an "active" form of the polymer was required. Polymer synthesized by cell-free S. mutans enzymes when added to S. mutans cells did not produce adherence. Purified antibody globulin, specific for the a-d site in the polysaccharide S. mutans group a antigen, completely inhibited adherence. Antibody to the second antigen present in the polysaccharide molecule, the a antigen, did not inhibit adherence. The evidence indicates that adherence did not require an antigenic binding site which might be common to all S. mutans strains. The orientation of the synthetase enzyme(s), antigenic binding site, and dextran-levan polymer on the cell surface is under study.


Transmission of lac by the sex factor E in Erwinia strains from human clinical sources. Lactose-utilizing (Lac(+)) strains of Erwinia spp. from human clinical material transfer lac by conjugation to plant strains of Erwinia herbicola and Erwinia amylovora, to other Erwinia strains from human clinical sources, and also to Escherichia coli, Paracolobactrum arizonae, Salmonella typhimurium, and Shigella dysenteriae. The frequency of this transfer varies with the donor and recipient strains employed. The lac genes appear stable in these exconjugants, and they are not cured by acridine orange. The Lac(+) exconjugants transfer lac to an Escherichia coli F(-) Lac(-) strain; the frequency of this transfer is high with E. herbicola and S. typhimurium exconjugants and relatively low with other exconjugants. The most studied Erwinia donor strain from human clinical material (EH133) and its Lac(+) exconjugants are insensitive to the F-specific phage, M13. P1-mediated transduction of lac, by using a Lac(+) exconjugant of E. coli as the donor and an E. coli F(-) Lac(-) strain as the recipient, revealed that all 50 Lac(+) transduced clones tested also inherited donor ability, suggesting a close linkage between the Erwinia sex factor (designated as E) and the lac genes. The E. coli culture harboring E-lac (E and the lac genes linked to it) does not restrict phages T1, T7, and lambdavir. E-lac is compatible with F'his, R100 drd-56 (F-like), and R64 drd-11 (I-like); cells harboring F'his or one of the R factors do not show super-infection immunity to the incoming E-lac, and E-lac plus one of the other plasmids can coexist stably in the same cell. The fertility of cells harboring F'his or R100 drd-56-as determined by the frequency of conjugal transfer of his or of the resistance determinant (Tet(r) in case of R100 drd-56) and also by sensitivity to F-specific phage (M13)-is not altered by the presence of E-lac, and this suggests that the sex factor E might belong to the fi(-) class.


Distribution and metabolism of 14C-tryptophan in normal and endotoxin-poisoned mice. dl-Tryptophan (benzene ring-(14)C) and its metabolites persist longer and in greater quantity in tissues of endotoxin-poisoned mice than in tissues of normal mice. Correspondingly less label is excreted in urine and feces and expired as (14)CO(2) in the poisoned animals. The distribution of label (1.1 x 10(6) dpm per microgram of tryptophan) was relatively constant whether it was administered alone or in combination with 20 mg of unlabeled l-tryptophan. Tryptophan must be metabolized through the tryptophan oxygenase pathway to be converted to carbon dioxide, but attempts to quantitatively correlate depressed tryptophan oxygenase activity with depressed carbon dioxide production were unsuccessful. It appears that neither tryptophan oxygenase nor substrate availability exclusively determine the quantity of tryptophan converted to (14)CO(2) except under highly selected conditions. The validity of an earlier suggestion that expired (14)CO(2) could be used to monitor in vivo tryptophan oxygenase activity is not supported by our data.


Comparative dynamics of salmonella infection after primary and secondary challenge of mice exposed to 10 and 23 C. Mortality of mice increased significantly as a result of cold exposure when the animals were challenged orally with Salmonella typhimurium, strain RIA. As reported earlier, cold exposure alone did not kill control animals nor did oral challenge at room temperature. No differences were apparent in the number of Salmonella per gram of liver-spleen, colon, or lung between groups of infected mice housed at 23 and 10 C. The number of bacteria increased equally in liver-spleen samples during the period of increasing mortality in the group housed at 10 C and the period of overt illness in those housed at 23 C. The ability to clear the bloodstream of a secondary intravenous challenge did not seem to be impaired by cold exposure. The bacterial load in the spleen and the rate of change in weight of that organ was equal in animals given a secondary challenge at 10 or 23 C. However, the absolute spleen weight was less in the cold-exposed group as was survival when the secondary challenge was administered 3 days after the primary oral challenge. The studies indicate that endotoxin from S. typhimurium may sensitize mice to the lethal effects of cold exposure. The increase in mortality observed in cold-exposed, infected mice is not due to greater bacterial proliferation in these animals. Rather, the combined stress effects of the bacterial agent(s) and cold may link lympholytic effects to impaired detoxification and increased energy demands, which often leads to lethal vascular collapse in cold-exposed, infected mice.


Antibody to Mycoplasma pneumoniae in nasal secretions and sputa of experimentally infected human volunteers. After experimental infection with Mycoplasma pneumoniae, 42% of 67 volunteers developed a threefold or greater rise in antibody in nasal secretions as measured by radioimmunoprecipitation. Development of an antibody increase in sputum was detected more often, i.e., in 73% of the volunteers. Each of the antibody increases involved immunoglobulin (Ig) A. Twelve rises in IgG antibody were detected in the specimens which exhibited a rise in IgA antibody. In almost every instance the rise in IgA antibody exceeded that seen with IgG antibody. Analysis of the response to experimental challenge with M. pneumoniae of volunteers with different levels of preexisting respiratory tract IgA antibody suggested that this secretory antibody was related to host resistance to M. pneumoniae disease. Further, respiratory tract IgA antibody appeared to be more directly related to host resistance than was antibody in serum.


Quantitation of immunoglobulin-bearing lymphocytes and lymphocyte response to mitogens in horses persistently infected by equine infectious anemia virus. A defect in lymphocyte function could be responsible for persistent infection by the equine infectious anemia virus. The number of lymphocytes bearing surface immunoglobulin, as detected by immunofluorescence, and lymphocyte response to mitogens were the same in uninfected and equine infectious anemia-infected animals. A defect in T or B lymphocyte numbers or ability to respond to stimuli was not detected in this chronic virus disease.


Failure of methylprednisolone to protect lead-sensitized rats against endotoxin. Methylprednisolone, in doses that protect normal rats against endotoxin, has no effect in lead-sensitized rats.


Immunization with Escherichia coli enterotoxin protects against homologous enterotoxin challenge. Immunization of rabbits with the culture filtrate of an enterotoxigenic strain of Escherichia coli 078: H12 resulted in the appearance of anti-enterotoxin activity in rabbit sera and protection of rabbit small intestine against homologous enterotoxin challenge.


Iatrogenic foreign body granulomas. A study of selected cases with the polarizing microscope.


In memoriam. Derrick T. Vail, M.D. 1898--1973.


Clinical experiments in cellular immunity in eye disease.


Viability of human trophoblast in vitro.


Nalidixic acid and hydroxynalidixic acid analysis in human plasma and urine by liquid chromatography.


The Lembert suture in the prevention of vaginal vault granulation after total abdominal hysterectomy.


Computer diagnosis of labor progression. I. Development of an on-line interactive digital computer program for the diagnosis of normal and abnormal cervical dilatation patterns.


Computer diagnosis of labor progression. II. Application of an on-line interactive prgram in 45 high-risk labors.


Letter: Malarial parasites in mammalian platelets.


Letter: Cannabinoid phenotypes in Cannabis sativa.


Letter: Inhibitory effect of potent interferon preparations on the regeneration of mouse liver after partial hepatectomy.


Letter: Growth of pulmonary alveolar macrophages in vitro.


Letter: Transplantation of interstitial cells of the testis.


Letter: Erythrocytes from animals with genetic muscular dystrophy.


Letter: Inherited differences in intensity of alcohol withdrawal reactions in mice.


Letter: Odour-blindness to musk: simple recessive inheritance.


Letter: Evidence for the theory of dual hypothalamic control of ovulation.


Letter: Lateral interaction between neural channels sensitive to texture density?


Letter: An anti-inflammatory peptide from bee venom.


Inhibition and activation of yeast phenylalanine and E. coli tRNA methylation.


Presurgical rearing environment alters exploration, fluid consumption, and learning of septal lesioned and control rats.


Electrode tip alignment and self-stimulation: influence of anodal hyperpolarization.


The effect of ablating the habenular nucleus of rats recovered from lesions of the lateral hypothalamus.


Escape from rewarding brain stimulation of dorsal brainstem and hypothalamus.


Letter: The effects of ploidy upon cell cycle dependent changes in x-ray sensitivity of Saccharomyces cerevisiae.


The otolaryngologist's role in myasthenia gravis.


Symposium: microsurgery of the outflow channels. Trabeculotomy.


Symposium: microsurgery of the outflow channels. Trabeculectomy.


Posterior vitreous detachment.

Posterior vitreous detachment.


Symposium: conservation of hearing in children. Impressions of the studies sponsored by the committee on conservation of hearing.


A tissue forceps.

A tissue forceps.


Symposium: microsurgery of the outflow channels. Clinical research.


Perspectives in neurosurgery.

Perspectives in neurosurgery.


Sickle-cell anemia in oral surgery.

Sickle-cell anemia in oral surgery.


Keratoplasty marker.

Keratoplasty marker.


Persuasion, power, and psychotherapy.

Persuasion, power, and psychotherapy.


Michel Eugene Chevreul. Experimental chemist and physicist: lipids and dyes.


A micrometer knife.

A micrometer knife.


A scleral expander for prevention of scleral collapse during intraocular surgery.


Nonpenetrating cardiac injuries: a collective review.


Tomas hook.

Tomas hook.


Immunologic findings in idiopathic cardiomyopathy: a prospective serial study.


Decision analysis as the basis for computer-aided management of acute renal failure.


Comparison of biopsy and fluorescent antibody staining techniques for the detection and study of onchocerciasis in an Ethiopian population.


Ultrastructural alterations of the follicular basement membrane in Hashimoto's thyroiditis. Report of eight cases with basement deposits.


Goodpasture's syndrome: failure of nephrectomy to cure pulmonary hemorrhage.


Ocular complications in renal transplant recipients.


Treatment of cervical dysplasia with electrocautery and tetracycline suppositories.


Carcinoma of the vulva: improvements in the surgical approach.


Enterocystoplasty and pregnancy.

Enterocystoplasty and pregnancy.


Pathophysiology of ureteral obstruction.


Ventilatory assistance in quadriplegia.

Ventilatory assistance in quadriplegia.


Self-stimulation loci in the midbrain central gray matter of the rat.


Effects of inescapable shock on subsequent avoidance performance: role of response repertoire changes.


Indirect immunofluorescence testing in bullous diseases.


Pustulosis palmaris et plantaris.

Pustulosis palmaris et plantaris.


Cutaneous vascular anatomy of pectoral skin flaps.


Gordon D. Hoople, M.D.

Gordon D. Hoople, M.D.


Comparison of clotrimazole cream, Whitfield's ointment and Nystatin ointment for the topical treatment of ringworm infections, pityriasis versicolor, erythrasma and candidiasis.


Grand rounds at the Albert Einstein College of Medicine Bronx, New York.


Letter: Retinoic acid versus placebo in linear verrucose naevi, scaly, lichenified eczema, and verrucae plantaris.


Annotation: viruses and leukaemia.

Annotation: viruses and leukaemia.


National and international otolaryngological societies.


Phagocytic function of leucocytes from patients with acute myeloid and chronic granulocytic leukaemia.


A comparison of the properties of chicken serum with other vitamin B12 binding proteins used in radioisotope dilution methods for measuring serum vitamin B12 concentrations.


Fine structure and peroxidase activity of circulating micromegakaryoblasts and platelets in a case of acute myelofibrosis.


Studies on the quantitation of immunoglobulin in human intestinal secretions. There is increasing evidence for the importance of the secretory immune system in the gut. In studies of local antibody production it is important to have satisfactory methods for measuring immunoglobulin concentrations and to be aware of the errors which may occur. Studies on immunoglobulin measurement in intestinal secretion by the radial immunodiffusion method are reported, showing the effects of proteolytic digestion, IgA molecular size, and sampling and storage conditions. Because of the presence of monomeric IgA in addition to secretory IgA, there is no satisfactory standard for IgA in gastrointestinal secretions, and only semi-quantitative results can be given. With radial immunodiffusion, IgG and IgM when subjected to tryptic digestion, and IgA when subjected to peptic digestion, may be overestimated because of the presence of fragments of immunoglobulins. In addition, pepsin rapidly destroys IgM and IgG. Both IgM and IgG are unstable in storage. The findings suggest that immunoglobulin concentration measurements in small intestinal aspirates should be interpreted with caution. These problems are also relevant to the detection of specific antibodies in gastrointestinal secretions.


Further studies on the role of 50 S ribosomal proteins in protein synthesis.


Mechanisms of active transport in isolated bacterial membrane vesicles. XV. Purification and properties of the membrane-bound D-lactate dehydrogenase from Escherichia coli.


Bacteriophage T7 lysozyme is an N-acetylmuramyl-L-alanine amidase.


Editorial: Professional Standards Review Organizations (PSRO).


The specificity of an ovine pituitary incubation system linked with gonadotrophin assays for detecting gonadotrophin releasing activity.


Changes in the luteinizing hormone releasing activity of the hypothalamus, and in pituitary gland and plasma luteinizing hormone during the oestrous cycle of the sheep.


The effects of synthetic gonadotrophin releasing factor on the release of luteinizing hormone and follicle-stimulating hormone from ovine pituitary tissue in vitro.


Total knee replacement-the Walldius hinge.


Hypothalamic stimulation of insulin release.


Detection of endotoxemia by the limulus test in patients with indwelling urinary catheters.


Non-Hodgkin's lymphoma in childhood: epidemiologic features.


Influence of age at exposure on the pathogenesis of Marek's disease.


Evaluation of the Walldius and other prostheses for knee arthroplasty.


The early history of neurosurgical anesthesia.


Paleoneurosurgery in Colombia.

Paleoneurosurgery in Colombia.


Lung uptake of 99mTc-sulfur colloid in organ transplantation.


Changes in Medicare law.

Changes in Medicare law.


Tribute to Dr. Robert Alexander Ross.

Tribute to Dr. Robert Alexander Ross.


Detection of renal allograft rejection with (125I) fibrinogen.


Characterisation of a drug resistant strain of Plasmodium falciparum from Sabah.


An investigation of endemic fascioliasis in Peruvian village children.


Labor complications.

Labor complications.


Drug therapy. Immunosuppressive agents. I.


Sounding board: raw vs. cooked data.

Sounding board: raw vs. cooked data.


Recent electrophysiologic studies on the Wolff-Parkinson-White syndrome.


Production of antibody to sheep red blood cells by human tonsil cells in vitro.


Pepsin inhibitory activity amongst activation peptides of pepsinogen.


Letter: Suppression of the cyclic surge of luteinizing hormone secretion and of ovulation in the rat by delta 1-tetrahydrocannabinol.


Letter: Potato blight teratogen.

Letter: Potato blight teratogen.


Letter: Associations between the incidence of neurological malformations and potato blight outbreaks over 50 years in Ireland.


Functional preservation of canine heart-lung preparations by perfusion with pure haemoglobin solution.


Letter: Effect of blood flow velocity on growth rate of platelet thrombi.


Letter: formation of nitrosamines in a meat curing mixture.


Smoking, pregnancy and publicity.

Smoking, pregnancy and publicity.


Training science teachers in methodology.


Preliminary characterization of two species of dsRNA in yeast and their relationship to the "killer" character.


Letter: Ribosomal DNA connectives between human acrocentric chromosomes.


T mycoplasmas on spermatozoa and infertility.


Histones and cancer test.

Histones and cancer test.


Anticomplementary activity of lipid A isolated from lipopolysaccharides.


Hemodynamic effects of small amounts of endotoxin in the bovine.


Localization of urate and phosphate reabsorption in the mongrel dog kidney.


Effect of protein and electrolyte on the spectral stabilization of concentrated solutions of indocyanine green.


Demonstration of a tubular basement membrane antibody in the pathogenesis of autoimmune nephrosis in rats.


Cerebrospinal fluid levels of endotoxin during endotoxemia.


Effect of gamma-irradiation on the synthesis of ribosomal RNA and ribosomal subparticles in Escherichia coli.


Tumoral disease induced in hamsters by human leukemic material.


Trypanosoma cruzi: the ultrastructure of culture forms as examined by carbon replication, freeze-etching and scanning electron microscopy.


Attempted transmission of Theileria gorgonis, Brocklesby & Vidler 1961, from Blue Wildebeest (Connochaetes taurinus) to cattle.


Serological studies on Theileria gorgonis using the indirect fluorescent antibody test.


Game anaplasmosis: the isolation of Anaplasma organisms from Antelope.


Intra-uterine fetal growth studied by ultrasonic biparietal measurements. The percentiles of biparietal distribution.


"Triggering" of ovulation after infusion of synthetic luteinizing hormone releasing factor (LRF).


Structure and function of chromatin.

Structure and function of chromatin.


Adrenal involvement in cryptococcosis.

Adrenal involvement in cryptococcosis.


Intracorneal hemorrhage.

Intracorneal hemorrhage.


Corneal stromal outgrowth.

Corneal stromal outgrowth.


Cyclocryotherapy for glaucoma pre- or postpenetrating keratoplasty.


Jan Purkinje and the ophthalmoscope.

Jan Purkinje and the ophthalmoscope.


A vitrectomy instrument in stereotaxic intraocular surgery.


Proteus mirabilis causing necrotic inflammation of the eyelid.


Normal conjunctival wound edge flora of patients undergoing uncomplicated cataract extraction.


Intraocular nocardiosis.

Intraocular nocardiosis.


Intravitreal amphotericin B treatment of experimental fungal endophthalmitis.


George Russell Callender, M.D. 1884-1973.


J. Robert Fitzgerald, M.D. 1910-1973.

J. Robert Fitzgerald, M.D. 1910-1973.


Split flap in head and neck reconstruction.


Basal cell carcinoma of the medial canthal region.


Interrelated role of maxillofacial prosthetics and reconstructive surgery.


One stage surgical repair of mandibular osteoradionecrosis with jaw preservation.


Frozen autogenous mandibular stent-graft for immediate reconstruction in oral cancer surgery.


Renewal systems in rods and cones.

Renewal systems in rods and cones.


A tribute to Jack C. Copeland.

A tribute to Jack C. Copeland.


The effect of short-term drying on the surface ultrastructure of the rabbit cornea: a scanning electron microscopic study.


Argon laser treatment of corneal neovascularization.


Aphakic astigmatism associated with persistent chromic gut sutures.


Single lung transplantation in experimental and human emphysema.


Renal transplantation for diabetic glomerulosclerosis.


Conditions that affect the colorimetric analysis of lipopolysaccharide from Escherichia coli and Treponema pallidum. Material extracted from the Nichols nonpathogenic strain of Treponema pallidum by phenol-water was analyzed by employing a recently reported colorimetric test for detection of lipopolysaccharide (LPS). The fraction isolated from T. pallidum, in combination with the reagent dye, absorbed maximally at a wavelength in the range reported to be positive for LPS. Comparison of this reaction to that of a commercial preparation of Escherichia coli LPS revealed that time and temperature of incubation of the LPS-dye complexes were important variables which had marked but different effects on the LPS of the two sources. However, with careful control of these parameters, concentration-dependent standard curves were established for LPS of both sources. Our results indicate the cell wall of T. pallidum is similar to that of gram-negative organisms.


Changes in renal function and intrarenal blood flow.


Viriditoxin production by Aspergillus viridi-nutans and related species. Bioproduction of viriditoxin on various substrates by strains of the Aspergillus fumigatus group was determined under several incubation conditions. Aspergillus viridi-nutans strains NRRL 4365 and 576 produced the largest quantities of toxin, A. brevipes gave reduced yields, and there was no detectable synthesis by isolates of four related species. After 30 days in static culture at 20 C on various autoclaved agricultural commodities, optimal yields of 440 and 380 mg of toxin were observed per kilogram of sorghum and rice. Toxin levels were reduced on corn, rye, and wheat (40-200 mg/kg); yields were low on cottonseed, barley, and oats. Incubation at 10 C restricted biosynthesis of viriditoxin, and no toxin accumulated on substrates maintained at 5 C for 120 days. In a liquid, yeast extract-sucrose medium, maximal mycotoxin production developed in shake flasks; after 156 h, 10 mg of toxin accumulated per gram of mycelium. Viriditoxin produced in submerged culture was associated with the mycelium; less than 1% was detected in the filtered broth after 156 h of incubation.


Evaluation of new urinary tract infection screening devices. Several new methods for detection of bacteriuria were studied to evaluate their usefulness as screening procedures. A new filter paper device incorporating dehydrated media and tetrazolium was found to be reliable when compared with the standard pour plate method in the laboratory and with the dip-slide method in a field test. It failed to detect yeasts and slowly growing streptococci. Antibiotics blocked the test when susceptible organisms were present. An agar-cup method was found to be quite reliable, but could be improved by use of differential media. The Griess test was confirmed in a small trial to be highly specific when used in conjunction with a first morning specimen, but of little value with random specimens. Phenzopyridine was found to give false positive reactions. The subnormal glucose test, although highly sensitive and specific, gave too many false positive tests to be useful other than as a screening method.


Evaluation of the improved Auxotab 1 System for identifying Enterobacteriaceae. The improved Auxotab Enteric 1 System is more accurate in identifying Enterobacteriaceae than is the original product, and results correlate better with those obtained with conventional tests.


Rapid identification of the taxon Rhodochrous in the clinical laboratory. Degradation of ethylene glycol in Middlebrook 7H-10 agar medium by 26 out of 29 strains of the taxon rhodochrous seems to permit its separation from rapidly growing mycobacteria and certain actinomycetes which only exceptionally showed this property.


The ataxic form of Creutzfeldt-Jakob disease.


Francis Martin Rouse Walshe. 1885-1973.

Francis Martin Rouse Walshe. 1885-1973.


pH- and anion-dependent salt modifications of alkaline phosphatase from a slightly halophilic Vibrio alginolyticus.


Purification of thioredoxin from Escherichia coli and bacteriophage T4 by immunoadsorbent affinity chromatography.


"Physiological" orbital implant.

"Physiological" orbital implant.


Precipitating antibodies against organic dust antigens in human sera by counterimmunoelectrophoresis.


Tension lung cyst as a complication of postoperative positive pressure ventilation therapy.


Management of bronchopleural fistula complicating therapy with positive end expiratory pressure (PEEP).


Electric otoscopy--a basic skill. Notes on the essentials of otoscopic examination and on the evaluation of otoscopes.


Acrodermatitis enteropathica: report of three new cases.


Repair of inguinal hernias in infants and children. The approaches of a pediatric surgeon.


Selective stimulation of mouse lymphocyte populations by lectins.


Immunological studies in burn patients. 3. Autoimmune phenomena.


Leprosy in Iran.

Leprosy in Iran.


Allotype suppression in the rabbit. I. The ontogeny of cells bearing immunoglobulin of paternal allotype and the fate of these cells after treatment with antiallotype antisera. The ability to distinguish immunoglobulin (Ig) of paternal allotype both on lymphocyte membranes and in the serum of neonatal b(4)b(5) heterozygous rabbits has allowed us to study the postnatal ontogeny of cells bearing endogenously synthesized Ig that could not have been derived from the mother. In normal b(4)b(5) rabbits, such endogenously synthesized Ig of paternal allotype is present on the membranes of bone marrow-derived (B) lymphocytes from birth, but does not appear as detectable circulating Ig until approximately 2 wk of age. In the neonate, cells bearing the paternal allotype are potential targets for the induction of chronic allotype suppression. Within 24 h of exposure to anti-allotype antisera in vivo, Ig of the suppressed paternal allotype is no longer detectable on the surface of neonatal lymphoid cells. Further, this lymphocyte membrane Ig is eliminated and not simply masked by the suppressing antibodies. Finally, cells bearing the suppressed allotype are deleted from all lymphoid organs for the duration of total allotype suppression, and reappear first in bone marrow and peripheral blood at the time of spontaneous escape from suppression.


Victor George Heiser, M.D. 1873-1972.

Victor George Heiser, M.D. 1873-1972.


Editorial by the President of the International Leprosy Association.


The cephalosporins--1973.

The cephalosporins--1973.


The production of migration inhibition factor by B and T cells of the guinea pig. Stimulation of sensitized lymphocytes by specific antigen in vitro leads to the production of migration inhibition factor (MIF). In the case of the pure soluble protein, or hapten-protein antigens used in the present studies, this MIF production was a property of the T lymphocytes in the cell suspensions. When PPD was used, B cells, as well as T cells, produced MIF. Similarly, PPD could stimulate B cells to mediate the macrophage disappearance reaction, a reaction which is known to be a T cell-dependent in vivo manifestation of cell-mediated immunity. Suspensions of lymphocytes from nonimmune donors could also be stimulated by PPD; in this case, B cells, but not T cells, produced MIF. The factors produced by the two lymphocyte subpopulations appeared to be similar, if not identical, on the basis of physico-chemical criteria. It is suggested that PPD stimulates B cells for MIF production because of its role as a B cell mitogen. The ability of endotoxin lipopolysaccharide, another B cell mitogen, to also induce MIF production by B cells supports this contention. Thus, although activation of lymphocytes for MIF production by specific antigen is a property of T cells, B cells as well as T cells may be so activated by agents which act nonspecifically. This may prove to have implications for in vivo events involved in immunization. In addition, these observations lend further support to the concept that lymphokine production represents a general biologic phenomenon in addition to playing a role in the effector mechanisms for reactions of cell-mediated immunity.


Antigenicity and cross-reactivity of penicillins and cephalosporins.


Mechanisms of resistance to cephalosporins in ampicillin-resistant Escherichia coli.


Cefazolin therapy of urinary tract infections.


Biology and ethology of Triatoma dimidiata (Latreille, 1811). 3. Habitat and blood sources.


Yoruban contributions to the literature on keloids.


Courts mandate that states implement an early screening and diagnostic program for children under Medicaid.


In vitro behavior of blood derived macrophages against killed M. leprae.


An immunofluorescent study of the identity of cells reacting with anti-lymphocytic sera.


The significance of glomerular deposits of immunoglobulin A.


An immunofluorescence study of the intestinal mucosa in ulcerative colitis and Crohn's disease.


A rapid identification test for Mycobacterium leprae.


Craniospinal dysraphia in the chick embryo.


Types of inflammation caused by oral prostheses.


The effect of neonatal thymectomy on Mycobacterium leprae infection in mice.


Composite impression procedures.

Composite impression procedures.


Prevention of complete denture problems by use of "overdentures".


Attachment of a splint to enamel of lower anterior teeth.


An evaluation of nonprecious alloys for use with porcelain veneers. Part I. Physical properties.


An evaluation of nonprecious alloys for use with porcelain veneers. Part II. Industrial safety and biocompatibility.


VA health care delivery: its relation to dentistry.


Palatal epithelial keratinization: prosthetic applications.


Practical approach to denture fabrication.


Emotional aspects of prosthodontic patients.


Precision techniques in partial denture prosthesis.


A classification utilized in the treatment of exceptional or terminal dentitions.


Major connectors for mandibular removable partial dentures: design and function.


Saddle-extension bridges: therapeutic alternatives in modern prosthodontics.


Minimizing problems in making a complete lower impression.


Methods of handling abutment teeth in class I partial dentures.


The contributions of gnathology to prosthodontics.


Nonsurgical prosthesis placed over implants.


Successful complete denture prosthodontics.


Causes and prevention of fixed prosthodontic failure.


Complete denture prosthesis: clinical review of accepted procedures.


Periodontal-prosthetic patterns in restorative dentistry.


Human factors in prosthodontic treatment.


Case analysis in the solution of bounded space problems.


Computerizing denture construction.

Computerizing denture construction.


The tooth-supported denture.

The tooth-supported denture.


Ultraviolet light polymerized restorative system: clinical report.


Induction of smooth muscle characteristics in renal interstitial fibroblasts during obstructive nephropathy.


Parasite counts in infections with Plasmodium falciparum.


Godfrey Joseph Burke Baldwin.

Godfrey Joseph Burke Baldwin.


Kevin Francis Anderson.

Kevin Francis Anderson.


Function and purification of gene 4 protein of phage T7.


Possible role of MSH in the mammal.

Possible role of MSH in the mammal.


Correlation between antimicrobial activity and peroxidase content of leukocytes.


Lipid motion and phodopsin rotation.

Lipid motion and phodopsin rotation.


Orotic aciduria and arginine deficiency.


Growth hormone and premature ageing.

Growth hormone and premature ageing.


Regional and historical aspects of lead pollution in Britain.


Tryptophanyl-tRNA and tryptophanyl-tRNA synthetase are not required for in vitro repression of the tryptophan operon.


Regulation of in vitro transcription of the tryptophan operon by purified RNA polymerase in the presence of partially purified repressor and tryptophan.


Synthesis of tryptophan operon RNA in a cell-free system.


Cell-free protein synthesis resulting in active phage Qbeta replicase.


Dr Donald Campbell: a reappraisal.

Dr Donald Campbell: a reappraisal.


Induction of group A bacteriocins of Serratia marcescens by nalidixic acid.


Charles Edward Laverty.

Charles Edward Laverty.


The synergistic action of ultraviolet and x radiation on mutants of Escherichia coli K-12.


A specific distortion of the human facial percept in childhood schizophrenia.


Morphine action at central nervous system sites in rat: analgesia or hyperalgesia depending on site and dose. Morphilne was injected via fine-gauge cannulas permanently implanted in various subcortical sites in the rat brain. In this way the blood-brain barrier was avoided and precise quantities of the drug were delivered to the intended sites. Ten micrograms of morphine in the posterior hypothalamus resulted in siginificant analgesia, while the same dose injected into the medial septum, the caudate, or the periaqueductal gray matter yielded hyperalgesia. The morphine-produced hyperalgesia at the last-mentioned site was accompanied by stereotyped violent circular leaps, an effect of morphine not previously reported. Thus, intracerebral injections of morphine differ significantly from systemic injections and produce either analgesia or hyperalgesia, depending on site and dose.


Tissue molds for cryostat embedding.

Tissue molds for cryostat embedding.


Excystation of Hymenolepis microstoma. II. Relative influences of proteolytic enzymes and bile salts.


Prevalence of Salmonella, Shigella and enteropathogenic Escherichia coli in young children in Kampala, Uganda.


Studies on the kidneys of mice infected with rodent Malaria. 3. Ultrastructure of the glomeruli at different stages of the disease.


Personality structure and development. A model and its application.


Platelets, thrombosis and coronary artery disease.


Susceptibility of mice to airborne Klebsiella pneumoniae infection in helium-oxygen atmospheres.


Arthur M. Master, MD, FACC. 1895 to 1973.


Concentration of nuclei in chicken muscle fibre in relation to the intensity of growth.


Surgical treatment of partial atrioventricular canal.


Isoenzymes of some oxydoreductases in the endocrine pancreas of guinea pig.


Diabetic angiography.

Diabetic angiography.


Mediastinitis following open-heart surgery. Review of two years' experience.


Vascular problems in replantation of limbs.


Angiographic evaluation in extracranial vascular occlusive disease.


Gas chromatographic-mass spectrometric isotope dilution assay for N,N-dimethyltryptamine in human plasma.


The myoglobin of primates. V. Prosimians: Galago crassicaudatus (thick-tailed galago) and Lepilemur mustelinus (sportive lemur).


MEDLARS II: a review.

MEDLARS II: a review. The MEDLARS II effort, as it was developed until June 1971, is reviewed in terms of the overall planning process. How MEDLARS I was approached by NLM is discussed first and its objectives used for comparison. Certain technical, managerial, and intellectual aspects are outlined as types of problems encountered in designing MEDLARS II. While improvement upon the MEDLARS I seemed to be the main reason for planning a MEDLARS II, objectives became blurred and divergent as the project went along. The complexities of creating a central computerized data base of health sciences bibliographic information and library functional activities for nationwide use were underappreciated and remain a challenge to NLM.


A comparison of drug literature coverage by Index Medicus and Drug Literature Index. We compared Index Medicus and Drug Literature Index during a search concerning the toxicity of eight drugs used in treating tropical diseases. Indexes covering the years 1969, 1970, and 1971 were searched. Index Medicus produced 198 citations and Drug Literature Index 309. There were seventy citations that appeared in both indexes, a duplication of 16%. Highest percentage of duplication for any one drug was 38.9%. We concluded that Index Medicus and Drug Literature Index provide complementary coverage in the area of drug toxicity and that, therefore, both tools should be consulted in searches of this nature.


Ototoxicity: a clinical review.

Ototoxicity: a clinical review.


Medical numismatic notes, XIV: commemorative medal issued at the Eleventh International Physiological Congress.


Diagnostic significance of the electrocochleogram in clinical audiometry.


Presentation of the Academy medal to Rebecca C. Lancefield, Ph. D.


The objective of verbal discrimination ability further investigations.


Presentation of the Academy plaque to Jerome P. Webster, M.D.


Recollections of a medical intelligence officer in World War II.


Obituary.

Obituary.


Georg von Békésy 1899-1972.

Georg von Békésy 1899-1972.


Yeast mutants resistant to bongkrekic acid, an inhibitor of mitochondrial adenine nucleotide translocation.


The amino acid sequence of the first 61 residues of chymosin (rennin EC 3.4.4.3).


Structure specificity of polydeoxyribonucleotides for the photoreaction with psoralen.


The amino acid sequence of a hitherto unobserved segment from porcine pepsinogen preceeding the N-terminus of pepsin.


The identification of the RNA binding site for a 50 S ribosomal protein by a new technique.


Purification of threonine deaminase from Escherichia coli.


Tentative amino acid sequence of hog pepsin.


Structural studies on isoleucyl-tRNA synthetase from E. coli.


Lack of stable initiation factor 3 (IF-3) binding to dimers of the 30 S ribosomal subunits.


On the cation sensibility of the vitamin B12-dependent methionine synthetase (5-methyltetrahydrofolate-homocysteine-methyltransferase from Escherichia coli).


Aminoacyl-tRNA binding sites in E. coli and reticulocyte ribosomes.


On the origin of mitochondrial mutants: evidence for intracellular selection of mitochondria in the origin of antibiotic-resistant cells in yeast. In wild-type Saccharomyces cerevisiae, erythromycin and certain other antibacterial antibiotics inhibit the formation of respiratory enzymes in mitochondria by inhibiting translation on mitochondrial ribosomes. This paper is concerned with the origin of mutant cells, resistant to erythromycin by virtue of having a homogeneous population of mutant mitochondrial DNA molecules. Such mutant cells are obtained by plating wild-type (sensitive) cells on a nonfermentable substrate plus the antibiotic. Colonies of mutant cells appear first about four days after the time of appearance of established mutant cells; new colonies continue to appear, often at a constant rate, for many days. Application of the Newcombe respreading experiment demonstrates that most or all of the mutant cells which form the resistant colonies on selective medium arise only after exposure of the population to erythromycin. It is suggested that this result is most probably due to intracellular selection for mitochondrial genomes. Resistant mitochondria arising from spontaneous mutation are postulated to be at a selective disadvantage in the absence of erythromycin; reproducing more slowly than wild-type sensitive mitochondria, they cannot easily accumulate in sufficient numbers in a cell to render it resistant as a whole. In the presence of erythromycin, resistant mitochondria can continue to reproduce while sensitive mitochondria cannot, until there is a sufficient number to make the cell resistant, i.e. to permit normal cell growth. The same phenomenon is seen with respect to chloramphenicol resistance. Intracellular selection is considered more likely than direct induction of mutation by the antibiotic, since mutant cells do not accumulate in the presence of erythromycin if the mitochondrial genome is rendered non-essential by growth on glucose or nontranslatable by chloramphenicol. Intra-cellular selection provides a mechanism for direct adaptation at the cell level, compatible with currently acceptable ideas of spontaneous mutation and selection at the organelle level.


Corticosterone and avoidance in rats with basolateral amygdala lesions.


Induction of mitotic crossing over in Saccharomyces cerevisiae by breakdown products of dimethylnitrosamine, diethylnitrosamine, 1-naphthylamine and 2-naphthylamine formed by an in vitro hydroxylation system. Dimethylnitrosamine and diethylnitrosamine, two potent carcinogens, are nonmutagenic when tested directly in microorganisms. Likewise 1-naphthylamine and 2-naphthylamine are also nonmutagenic but the N-hydroxy derivatives are mutagenic in microorganisms. Apparently these compounds require metabolism to breakdown products which are then the proximately active agents, and microorganisms lack the enzymes necessary to effect this conversion. These compounds are mutagenic in Saccharomyces after conversion to breakdown products in an in vitro hydroxylation medium. The induction of mitotic crossing over in Saccharomyces cerevisiae by breakdown products of dimethylnitrosamine, diethylnitrosamine, 1-naphthylamine and 2-naphthylamine formed in the Udenfriend hydroxylation medium is reported in this communication. Mitotic crossing over was detected as red sectored colonies resulting from induced homozygosity of the ade2 marker. Dimethylamine and diethylamine, which lack the nitroso group of the nitrosamines, did not induce mitotic crossing over under any of the test conditions. To further confirm that the induced sectored colonies were the result of mitotic crossing over they were tested for the presence of reciprocal products. The expected reciprocal products were found in over 67% of the isolates tested. The significance and practicality of using mitotic recombination as an indicator of genetic damage potential of chemicals is discussed.


Midbrain and motivated behavior.

Midbrain and motivated behavior.


Feeding and drinking pathways between medial and lateral hypothalamus in the rat.


Some behavioral effects of entorhinal cortex lesions in the albino rat.


Caudate nucleus and arousal in the rat.

Caudate nucleus and arousal in the rat.


Adenovirus-induced crystals: studies with temperature-sensitive mutants.


Cultivation of the fixed rabies virus strain HEP Flury in vitro. I. Adaptation of the HEP Flury strain to the human diploid cell line HEL.


Group A beta hemolytic streptococci in skin lesions among an Egyptian school children population.


Application of cohort isolation principles to the rooming-in of babies and their mothers in hospital staphylococcal cross-infections.


Incidence of R factors in children. 2. Contribution to the ecology of R factors in child communities.


Indiana frontiers in medical education.

Indiana frontiers in medical education.


An improved band and loop space maintainer.


Evaluation of the preformed stainless steel crown.


In memoriam. Eors Bajusz M.D., Ph.D. 1926-1973.


A simple system of evaluating occlusions in the sagittal plane.


Mixed dentition: development, diagnosis, and treatment.


Mechanism of nerve destruction in tuberculoid-borderline leprosy. An electron-microscopic study.


Role of the glandular vas deferens in the development of Ascaris spermatozoa.


Facial patterns and skeletal configurations.


Bacteriologic and histologic examination of Stephanurus dentatus parasitizing swine ureters.


Scanning electron microscopy of trematodes embedded for transmission electron microscopy.


Scanning electron microscopy of the human pubic louse, Pthirus pubis (Linnaeus, 1758).


Hot water as a tool in mass field preparation of platyhelminthic parasites.


The inhibition of migration of guinea pig peritoneal cells incubated with donor and autologous lymphocytes.


Inhibition of phagocytosis: effects of normal rabbit serum on E. coli uptake by rabbit alveolar macrophages.


Modification of the response to Freund's adjuvant by chloramphenicol.


Formation of the recombinant between ampicillin resistance determinant and transfer factor.


Development of a sensitive microbioassay using amplified cultivation.


Detection of a specific surface antigen(s) in adenovirus type 12-transformed cells by fluorescent antibody technique.


Alternate changes of surface antigen(s) in adenovirus type 12-transformed and tumor cells.


Sodium hypochlorite and sodium perborate: preferential inhibitors of DNA polymerase-deficient bacteria.


Impaired delayed-hypersensitivity responses in 154 patients with untreated Hodgkin's disease.


Detection of ferritin as a circulating tumor-associated antigen in Hodgkin's disease.


Studies on transcription by the use of antibodies against DNA.


Hodgkin's disease in Western Europe: a review.


Functions of rII genes of T4 bacteriophage. Communication I. Structure of replicating DNA of bacteriophage T4r+ and T4r 1272 in E. coli cells.


Hodgkin's disease in Asia, particularly in Japan.


International Symposium on Hodgkin's Disease. Session 4. Small group workshops. Report on workshop: Experimental cytology and histopathology.


Some unusual kinetic characteristics of "biosynthetic" L-threonine dehydratase of Escherichia coli.


Hodgkin's disease in Israel.

Hodgkin's disease in Israel.


International Symposium on Hodgkin's Disease. Session 5. Treatment. Current status of clinical trials: Stanford experience, 1962-72.


Morbus Hodgkin's disease, stages I and II: trial of the European Organization for Research on Treatment of Cancer.


Specific chemical modification of the ribosome close to the peptidyl transferase center.


Progress report. Hodgkin's clinical trial, 1972.


International Symposium on Hodgkin's Disease. Session 6. Survival data and prognosis. Invited discussion: Forcing a sequential experiment to be balanced.


International symposium on Hodgkin's disease. Session I. Epidemiology and etiology. Part 3. Immunology. Introduction.


In vitro evidence of normal lymphocyte function in some patients with Hodgkin's disease and negative delayed cutaneous hypersensitivity.


History of medicine in Prince Edward Island.


Nutrition classics from The Journal of Biological Chemistry 20:379-389,1915. Further observations of the influence of natural fats upon growth.


Calusterone (7beta,17alpha-dimethyltestosterone) as primary and secondary therapy of advanced breast cancer.


Dedication to Prof. Gerlings.

Dedication to Prof. Gerlings.


Ultrasonic hypophysectomy in acromegaly. Report of 41 cases.


A short review of the collaboration between the Utrecht departments of oto-rhinolaryngology and of neurosurgery and a contribution to some macro-surgical aspects of transsphenoidal hypophysectomy.


The missing incus.

The missing incus.


Three useful ways to avoid amputation in advanced Dupuytren's contracture.


Pathogenesis and pathomechanics of rheumatoid deformities in the hand and wrist.


Results and complications of flexor tendon grafting.


Electromyography and nerve conduction as a diagnostic aid.


Primary upper small intestinal lymphoma (so-called Mediterranean lymphoma).


Pathobiology of lymphocyte interactions.


Cervical intraepithelial neoplasia.

Cervical intraepithelial neoplasia.


A new metabolic control mechanism. IV. Enzymes as measuring systems of substrates quantum properties.


Polyamines and transfer RNA-methylation in mouse leukemic cells.


Observations on the pH dependence of the glutaminase activity of a glutamine amidotransferase, carbamylphosphate synthetase. Glutamine-dependent carbamylphosphate synthetase (Escherichia coli) is composed of a heavy subunit (molecular weight about 130,000) and a light subunit (molecular weight about 42,000), which can be separated with retention of catalytic activities. The separated heavy subunit can catalyze activation of CO(2) by ATP and synthesis of carbamylphosphate from ammonia (but not from glutamine). The only catalytic activity exhibited by the separated light subunit is the ability to hydrolyze glutamine; the separated heavy subunit does not exhibit glutaminase activity. The pH-activity curve of the glutaminase activity of native carbamylphosphate synthetase exhibits maxima at about pH 4.2 and 9.5, while the glutaminase activity of the separated light subunit exhibits only a single optimum at about pH 6.7. When the light and heavy subunits are recombined, the two pH optima characteristic of native enzyme are restored. Glutaminase activities of native enzyme at both pH optima are similarly inhibited by the glutamine analog, L-2-amino-4-oxo-5-chloropentanoic acid, and also by dithiothreitol. Storage of native enzyme at pH 9 abolishes the glutaminase optimum at acid pH, but greatly increases the activity at alkaline pH. Treatment of native enzyme with N-ethylmaleimide increases the glutaminase activity dramatically and converts the pH profile to one that closely resembles that of the isolated light subunit. The data indicate that the same active site is involved in hydrolysis of glutamine at both acid and alkaline values of pH, and that this property of the enzyme depends upon interactions between the heavy and light subunits of native enzyme. The double-optima behavior of native enzyme seems to be related to participation of different catalytic groups of the enzyme which affect the maximum velocity rather than the binding of substrate. The findings offer additional evidence for occurrence of significant interactions between the subunits of carbamylphosphate synthetase, and may have significance in relation to other glutamine amidotransferases, including glutaminases.


Dansyl-galactoside, a fluorescent probe of active transport in bacterial membrane vesicles. A fluorescent galactoside, 2-(N-dansyl)-aminoethyl beta-D-thiogalactoside (dansyl-galactoside), competitively inhibits lactose transport by membrane vesicles of Escherichia coli, but is not actively transported. An increase in dansyl-galactoside fluorescence is observed upon addition of D-lactate. The fluorescence increase is not observed in membrane vesicles lacking the beta-galactoside transport system, and is blocked or rapidly reversed by addition of beta-galactosides, sulfhydryl reagents, inhibitors of D-lactate oxidation, or uncoupling agents. The fluorescence increase exhibits an emission maximum at 500 nm and excitation maxima at 345 nm and at 292 nm. The latter excitation maximum is absent unless D-lactate is added, indicating that the bound dansyl-galactoside molecules are excited by energy transfer from the membrane proteins. Titration of vesicles with dansyl-galactoside in the presence of D-lactate demonstrates that the beta-galactoside carrier protein represents about 3.3% of the total membrane protein. The data indicate that D-lactate oxidation leads to binding of the fluorescent galactoside to the beta-galactoside carrier protein in such a manner that the dansyl group is transferred to a hydrophobic environment within the membrane.


A method for detecting pyrimidine dimers in the DNA of bacteria irradiated with low doses of ultraviolet light. Cells of Escherichia coli treated with lysozyme and Brij-58 become permeable to proteins, but do not release their DNA. I incubated permeable cells with an endonuclease that produces single-strand breaks in DNA-containing pyrimidine dimers. The enzyme entered the permeable cells, and, if they had been irradiated with ultraviolet light, caused breaks in their DNA. The frequency of breaks was estimated from the sedimentation pattern of the DNA in alkaline sucrose gradients. The procedure is sensitive enough to detect the dimers produced by a dose of 10 erg/mm(2) at 254 nm, or about 50 dimers per E. coli genome. This method exemplifies and extends the use of permeabilized cells for examining biological processes at the molecular level.


Autoregulation: a role for a biosynthetic enzyme in the control of gene expression. It was previously proposed, primarily on the basis of evidence in vitro, that L-threonine deaminase, the ilvA gene product, is required for repression of its own synthesis and for repression of the other genes in the ilv-ADE operon. In this communication, evidence in vivo is presented that supports this autoregulatory model. Further evidence is presented that suggests that L-threonine deaminase is also required for induction of the ilvC gene product. The autoregulatory model is presented in an expanded form to include recent evidence that L-threonine deaminase (EC 4.2.1.16) is a central element for repression of the ilvADE and ilvB operons, and for induction of the ilvC operon.


Ribosomal assembly influenced by growth in the presence of streptomycin. Translational leakiness (i.e., nonspecific suppression) of nonsense mutants of bacteriophage T4 is increased in cells of certain streptomycin-resistant strains previously grown in the presence of streptomycin. Concomitantly, ribosomes extracted from these streptomycin-grown cells possess a high level of misreading. Increased suppression ability as well as ribosomes that highly misread accumulate with kinetics expected for a constant differential rate of synthesis of a new product induced by drug action. The misreading ribosomes do not contain appreciable amounts of streptomycin and the misreading property is lost by exposure to high salt concentrations. It is suggested that streptomycin (or dihydrostreptomycin, or paromomycin) induces a reversible modification in 30S subunit assembly without physically participating in the modified structure. The extent of this modification appears dependent upon the strA allele.


Directory of the National Academy of Sciences of the United States of America.


An inherited blood group A variant in the Finnish population. I. Basic characteristics.


Identification of 50S proteins at the peptidyl-tRNA binding site of Escherichia coli ribosomes. Bromoacetyl-phenylalanyl-tRNA(phe) bound to 70S E. coli ribosomes reacts covalently with proteins of the 50S subunit. The major reactions are with proteins L2 and L27. In the presence of poly(U), 70S-bound bromoacetyl-phenylalanyl-tRNA(phe) can participate in peptidebond formation with phenylalanyl-tRNA(phe) or puromycin. Most of the products of these reactions are also found covalently attached to L2 and L27. Chloramphenicol and sparsomycin markedly inhibit the peptide-bond formation. These results strongly suggest that bromoacetylphenylalanyl-tRNA(phe) can function as a normal peptidyl-tRNA and that the 50S proteins, L2 and L27, are located in the peptidyl-tRNA binding site. The side reactions of bromoacetyl-phenylalanyl-tRNA(phe) are with one or more 50S proteins from the set L14-17, L6 and/or L11, and L26. These occur to a much less extent than the reactions with L2 and L27. Any functional significance of the side reactions is unknown.


Transfusion in the presence of anti-Sp1.


A specific inhibitor of polypeptide-chain initiation in Escherichia coli. An inhibitor of polypeptide-chain initiation was isolated from E. coli cells. This protein inhibits formation of the 30S or 70S initiation complex with either fMet-tRNA(f) as initiator and AUG, MS2 RNA, or late T4 RNA as messenger, or acPhe-tRNA as initiator and poly(U) as messenger. Chain elongation, e.g., poly(U) translation at high Mg(2+) concentration, is not inhibited. The inhibitor is rendered ineffective when active aminoacylation of tRNA is taking place, e.g., during natural mRNA translation. This inhibitor is distinct from the so-called interference (i) factors, which interfere exclusively with the action of initiation factor 3. Since the new inhibitor can apparently be turned on and off, it may have a regulatory function in translation.


In vivo splicing of protein: one continuous polypeptide from two independently functioning operons. Active-beta-galactosidase (EC 3.2.1.23) is often formed in rec(-) merozygotes containing a pair of mutations in the z gene of the lac operon. Contrary to expectation, with certain pairs of mutants this enzyme, upon dissociation, does not yield two independent polypeptides but only a single continuous protomer. Both genetic recombination and suppression have been ruled out as the source of this phenomenon. Therefore we believe we are observing the synthesis of one protein from two independently functioning genes.


General therapeutic and prophylactic problems in the treatment of atherosclerosis.


Cardiac dysrhythmias during anaesthesia.


"Risk factors" in ischaemic heart disease.


Relation of age, diastolic pressure and known duration of hypertension to presence of low renin essential hypertension.


Clinical implications of pulmonary hypertension in mitral stenosis.


Measurement of left anterior descending coronary arterial blood flow. Technique, methods of blood flow analysis and correlation with angiography.


Fiedler on acute interstital myocarditis (1899). II.


Computer-assisted eye examination. I. Computer-actuated eye refractors.


Editorial: How radiology became established in Utah.


Slit-scan cytofluorometry: basis for an automated cytopathology prescreening system.


Introduction of the Caldwell lecturer, 1971.


Roentgenologic findings in recurrent pyogenic cholangitis.


Deficient acquisition and retention of a visual-tactile discrimination task in rats with medial thalamic lesions.


Differential effects of one- vs two-stage amygdaloid lesions on activity, exploratory, and avoidance behavior in the albino rat.


The conformational stability of ribosomal proteins L7 and L12 from E. coli. I. Circular dichroism study of the changes induced by ionic strength and solvents.


Prospects of chemosterilant and genetic control of rodents. This paper discusses some requirements of an ideal rodent chemosterilant, analyses the advantages of chemosterilants over other control methods, and compares the potential values of chemosterilants that affect females, males, and both sexes. Examples are given of specific situations where chemosterilants will be valuable in rodent control, together with suggested methods of applying them. The theory and practicability of using genetics in rodent control are also discussed. Neither the chemosterilant nor the genetic method is expected to become a panacea, but their eventual application will be a significant advance in rodent-control technology. Since both approaches are based on sound biological principles and are relatively safe, they should be helpful in regulating rodent populations in the future.


Some reminiscences of a charter member.

Some reminiscences of a charter member.


Trypanosoma lewisi: electron microscopy of the infected spleen.


Trypanosoma cruzi: interaction with vertebrate cells in vitro. 1. Individual interactions at the cellular and subcellular levels.


Trypanosoma cruzi: interaction with vertebrate cells in vitro. 2. Quantitative analysis of the penetration phase.


Plasmodium gallinaceum: selective immunosuppression by cyclophosphamide in preerythrocytic malaria.


Towards a methodology of teleonomy.

Towards a methodology of teleonomy.


Differentiation of neuroblastoma cells induced by nerve growth factor in vitro.


Induction of alloxan diabetes in obese-hyperglycemic mice (genotype obob).


Structural constituents of clinically normal and slightly inflamed dog gingiva. A morphometric study.


Studies on mouse liver urate oxidase. I. Immunofluorescent localization of urate oxidase in mouse liver.


Immunologic responsiveness of young AKR mice to iodoacetate and to iodoacetate-treated tumor cells.


Affinity labeling anti-p-azobenzenearsonate antibodies using bromoacetyl derivatives of homologous hapten.


Phagocytosis as a surface phenomenon. 3. Influence of C1423 on the contact angle and on the phagocytosis of sensitized encapsulated bacteria.


Review of chronic secretory otitis and allergy.


Differentiation of T-cell precursors in nude mice demonstrated by immunofluorescence of T-cell membrane markers. When the thymus from an AKR mouse (TL(-), theta-AKR) is grafted to a BALB/c-nu/nu mouse (TL2, theta-C3H), the grafted thymus is rapidly repopulated by host lymphocytes, i.e., lymphocytes having the TL2 and theta-C3H T-lymphocyte membrane antigen markers. theta-C3H lymphocytes also appear rapidly in the spleen and lymph nodes. After a few weeks, BALB/c nude mice grafted with AKR thymus and normal BALB/c mice could not be distinguished on the basis of the number of TL-positive thymocytes or theta-C3H-positive lymphocytes in thymus, spleen, or lymph nodes. These experiments give a definitive proof of the existence of precursor cells for the T compartment of the lymphoid system in the nude mouse. They strongly suggest the involvement of host-derived T cells in the recovery of some T-cell functions by nude mice grafted with allogeneic thymuses.


A new surface marker on T lymphocytes of human peripheral blood. Neuraminidase treatment of human peripheral blood lymphocytes uncovers cell surface receptors that bind purified A hemagglutinin from the snail Helix pomatia. No hemagglutinin was bound to untreated lymphocytes. Binding studies with (125)I-labeled hemagglutinin suggested that the number of receptors on neuraminidase-treated lymphocytes was approximately 1.10(6)/cell. The apparent association constant for hemagglutinin binding to lymphocytes, as calculated from Scatchard's plots, was 5-7.10(8) liters/mol. Immunofluorescent staining with FITC-conjugated hemagglutinin gave positive reactions with approximately 60% of the lymphocytes from normal donors. Positive staining was inversely related to the number of lymphocytes with Fc or complement receptors or with surface immunoglobulin, thus suggesting that See PDF for Structure the lymphocytes with receptors for Helix pomatia A hemagglutinin are T cells. Cell fractionation on columns charged with hemagglutinin indicate that these receptors may be used for separating subpopulations of human peripheral lymphocytes.


Requirement for alpha-L-fucose on the macrophage membrane receptor for MIF. alpha-L-fucose abolishes the activity of guinea pig migration inhibitory factor (MIF) on the macrophages. Other sugars such as alpha-D-glucose, beta-D-galactose, alpha-L-rhamnose, methyl-alpha-D-mannoside, and N-acetyl-beta-D-glucosamine had no effect. Theabolition of MIF activity by alpha-L-fucose was reversible. When macrophages were incubated with alpha-L-fucosidase, a glycosidase which splits terminal alpha-L-fucose from oligosaccharides, the macrophages no longer responded to MIF. On the other hand, MIF incubated with alpha-L-fucosidase was still active. These experiments strongly suggest that alpha-L-fucose comprises an essential part of a macrophage membrane receptor for MIF.


Specific heterologous enhancement of immune responses. V. Isolation of a soluble enhancing factor from supernatants of specifically stimulated and allogeneically induced lymphoid cells.


Differentiation of lymphoid cells: effect of serum and other mitogenic agents on the selective induction of immunoglobulin M secreting lymph node cells in tissue culture.


Mechanisms of endotoxin tolerance. 8. Specificity of serum transfer.


Vitamin A: adjuvant and steroid antagonist in the immune response.


Presence of impairment of humoral immunity in nonadherent spleen cells of old mice.


Immune responses in vitro. IX. Role of cell clusters.


Change in susceptibility of C3H-HeJ mice to LCM virus infection.


A mathematical model for the quantitation of tumor and antibody-forming cell populations within an animal's body.


Characterization of glass adherent human mononuclear cells.


The concept of health: an historic and analytic examination.


Bacteriology of and cleaning methods for stock earmolds.


Some biochemical, histological, radiological and clinical features of renal osteodystrophy.


Parathyroidectomy in the treatment of secondary renal hyperparathyroidism.


Validity of a diagnostic test designated by a single function.


Effects of cycloheximide on RNA polymerase specific activity and encystment in Acanthamoeba castellanii.


Rapid and selective inhibition of the synthesis of high molecular weight RNA in yeast by lomofungin.


Long-term stimulation of cat fast-twitch skeletal muscle.


Depression of the T cell phenomenon of contact sensitivity by T cells from unresponsive mice.


Precision of development in chick limb morphogenesis.


Growth hormone regulation by melatonin and serotonin.


Ethanol and methanol metabolites in alcohol withdrawal.


Isolation and characterization of agent causing swim bladder inflammation in carp.


Nitrosamines in cigarette smoke condensate.


Effect of heat on the identification of asbestos by x-ray diffraction.


Hypermethylated tRNA in cleaving rabbit embryos.


Inhibition and reversal of platelet activation by cytochalasin B or colcemid.


Griseofulvin inhibits fungal mitosis.

Griseofulvin inhibits fungal mitosis.


Properties of cystinotic fibroblast-D98 cell hybrids studied by somatic cell hybridization.


Antimitotic action of griseofulvin does not involve disruption of microtubules.


Induction of mitotic synchrony by intermittent hyperthermia in Ehrlich carcinoma in vivo.


Differential effect of myleran on two normal haemopoietic progenitor cell populations.


Possible discontinuous retinal rod outer segment formation in Latimeria chalumnae.


Effect of Toxoplasma gondii on the thymus.


Geological antiquity of Rhodesian man.

Geological antiquity of Rhodesian man.


Reconstruction of the denal arcades of Ramapithecus wickeri.


Cascade activation of genome transcription in wheat.


Letter: Mercury in lakes.

Letter: Mercury in lakes.


Dr Muriel Robertson.

Dr Muriel Robertson.


Hypothesis on differentiation and the inheritance of gene superstructure.


Quantitative correlation between the proton-carrying and respiratory-stimulating properties of uncoupling agents using rat liver mitochondria.


Proton radiographic detection of strokes.


Effect of antitumour polysaccharides on the higher structure of serum protein.


Defects in tactile directional sensitivity after forebrain commissurotomy in man.


Colour opponent neurones in the human visual system.


Spatial frequency selectivity of a visual tilt illusion.


Electrical coupling across developmental boundaries in insect epidermis.


A simple method for determining relative reward value of brain stimulation.


Increased activity following fornix transection in the female rat.


Isolation of obligate anaerobic faecal bacteria using an anaerobic glove cabinet.


In memoriam: Harry Berelowitz.

In memoriam: Harry Berelowitz.


Use and technic of fasciotomy as an adjunct to limb salvage.


Serratia endocarditis in patients with a Starr-Edwards valve: report of a case of bacteriologic cure with antimicrobial therapy.


Officers southern medical association 1972-1973.


George J. Carroll, M.D. leading Virginia pathologist to become president of SMA.


In memoriam M. Pinson Neal, Sr., MD Columbia, Missouri 1887-1973.


Immunodepressant activity and 6-mercaptopurine levels after administration of 6-mercaptopurine and azathioprine.


Variations in expression of cell membrane antigens by cultured cells. A study of antilymphocytic globulin binding by human lymphoblastoid cells before, during, and after their establishment as cell lines.


Primarily vascularized allografts of hearts in mice. The role of H-2D, H-2K, and non-H-2 antigens in rejection.


Cardiac transplantation in mice. V. Prolongation of allografts with cell-free extracts and antithymocyte globulin.


The effect of incubation in vitro with triamcinolone acetonide on murine heart and skin allograft survival.


Improvement of blood flow in transplanted kidneys in dogs using a frusemide-added perfusate.


Prolongation of kidney allografts perfused by antilymphocyte globulin in vitro.


The role of pulsatile flow in kidney preservation.


Bone marrow origin of nonsensitized effector cells in skin allograft rejection.


Reassessment of nonpulsatile flow for renal hypothermic perfusion.


External herniae--inguinal hernia.

External herniae--inguinal hernia.


Ross Institute bulletins.

Ross Institute bulletins.


The blind-loop syndrome and its variants. Microbiologic aspects of diagnosis and treatment.


Experimental infection in man with Plasmodium malariae.


Five day primaquine therapy--an evaluation of radical curative activity against vivax malaria infection.


The interaction of Brugia malayi and streptococcus in an animal model.


Biliary calculus associated with opisthorchiasis.


The fate of nebulized salbutamol (albuterol) administered by intermittent positive pressure respiration to asthmatic patients.


Efficiency of nebulizers for depositing saline in human lung.


Positive end-expiratory airway pressure in severe arterial hypoxemia.


The pattern of development of emphysema in the human lung.


Ultrastructure of the pulmonary lymphoid tissue.


Ultrastructure of pulmonary alveolar macrophages in situ in lungs from rats exposed to ozone.


Treatment of acute pleuritic pain. Comparison between indomethacin and a placebo.


Cutaneous alternariosis with mixed infection of Candida albicans. Report of a patient responding to natamycin.


Reticulosarcoma of vulva complicating azathioprine-treated dermatomyositis.


Letter: A note on medical history.

Letter: A note on medical history.


Editorial: The first laryngectomy for carcinoma.


An anomaly of the posterior crista in man.


Editorial: 100 years of antrotomy. Schwartze Centennial Memorial Lecture.


J. M. Hunter.

J. M. Hunter.


J. Dewar.

J. Dewar.


R. N. Colley.

R. N. Colley.


Breast milk substitute: a bacteriological study. The increased susceptibility of infants fed on cows' milk preparations has been attributed, at least in part, to differences in the nature of the large-bowel content-owing to the acidity of the faeces and their high content of Lactobacillus bifidus. In an attempt to mimic these features of the breastfed infant in one who is fed artificially, a breast milk substitute was devised which resembles breast milk in several important ways. When this material was fed to newborn infants the faeces developed the characteristics of those of the breast-fed child.


Luteinizing hormone and follicle stimulating hormone-releasing hormone test in patients with hypothalamic-pituitary-gonadal dysfunction. A standard intravenous 100 mug luteinizing hormone/follicle stimulating hormone-releasing hormone (LH/FSH-RH) test was used to assess the pituitary gonadotrophin responses in 155 patients with a variety of diseases of the hypothalamic-pituitary-gonadal axis. In all but nine patients there was an increase in circulating levels of either LH or FSH in response to the releasing hormone though 137 (88%) were clinically hypogonadal. It was not possible with this test to distinguish between hypothalamic and pituitary causes of hypogonadotrophic hypogonadism, since a variety of LH and FSH responses emerged within the disease groups. However, primary gonadal failure characteristically resulted in exaggerated gonadotrophin response. The potential therapeutic use of the gonadotrophin releasing decapeptide is suggested in certain patients with hypogonadotrophic hypogonadism.


Vagotomy or gastrectomy for gastric ulcer. Patients treated in a randomized controlled comparison of management of benign gastric ulcer of the body of the stomach, comprising 50 patients treated by Billroth I partial gastrectomy and 50 patients treated by vagotomy and pyloroplasty and biopsy of the ulcer, were followed up for about five years (range one and a half to eight and a half years). No statistically significant difference has been found between the functional results (Visick grading) of the two groups. There was no operative mortality. Postoperative morbidity (17 against 5) and length of stay in hospital (14 against 10 days) were significantly greater after gastrectomy. Seven patients after vagotomy have been submitted to gastrectomy (three for recurrent gastric ulceration, three for gastric cancer, and one for bleeding), which is a statistically significant excess compared with no reoperation after gastrectomy. While vagotomy and pyloroplasty can be useful to avoid a technically difficult gastrectomy, it cannot be said to replace partial gastrectomy in the treatment of gastric ulcer.


Double-blind cross-over study of ketoprofen and ibuprofen in management of rheumatoid arthritis. A double-blind cross-over study of ketoprofen (Orudis) 150 mg daily and ibuprofen (Brufen) 1,200 mg daily was carried out in 35 outpatients with rheumatoid arthritis. Results suggest that analgesic and anti-inflammatory activity of ketoprofen is superior to that of ibuprofen. Significantly greater pain relief (P < 0.05) and reduction in joint circumference (P < 0.01) was obtained with ketoprofen than with ibuprofen. Side effects of the drugs were comparable and not serious.


Tetracycline-resistant beta-haemolytic streptococci in South-west Essex: decline and fall. The prevalence of tetracycline-resistant beta-haemolytic streptococci in South-west Essex has been recorded over the past 10 years. It has fallen from a peak of 35% in 1965 to a level of 9.2% in 1972. Ear infections no longer provide the highest incidence of these organisms; vaginal, perineal, and skin infections now seem to be of greater relative importance but throat swabs still provide the greatest actual number of isolations. Erythromycin-resistant strains are still rare.


Methods for determining the amount of glucose in blood.


Status of the use of universal donor blood transfusion.


Selection and orientation of lung tissue for scanning and transmission electron microscopy.


Development of normal and genetically dystrophic mouse muscle in tissue culture. I. Prefusion and fusion activities of muscle cells: phase contrast and time lapse study.


The cytotoxic effect of macrophages studied by time-lapse microcinematography.


Effect of acetaldehyde and glutaraldehyde fixation on the surface properties of red blood cells as determined by partition in aqueous phases.


Losses of material during cytological preparation of nuclei and chromosomes.


Detection of DNA polymerase activity in fixed cells.


Cultures grown and embedded in situ on Spurr discs, a low viscosity epoxy resin for electron microscopy.


Flame-resistant fabrics.

Flame-resistant fabrics.


The effect of radiation sensitizing and protective agents on the post-irradiation synthesis of DNA by membrane complexes of Escherichia coli B-r.


Malnutrition, hunger, and behavior. I. Malnutrition and learning.


Malnutrition, hunger, and behavior. II. Hunger, school feeding programs, and behavior.


The hisP protein, a known histidine transport component in Salmonella typhimurium, is also an arginine transport component. The hisP protein is an essential component of the high-affinity histidine transport system in Salmonella typhimurium. Our present studies demonstrate that this protein is also an essential component of an arginine transport system. Strains with a mutation in the hisP gene are unable to transport arginine for use as a sole nitrogen source. However, such strains have normal high-affinity transport of arginine, indicating that the hisP protein is not required for all arginine transport systems. Histidine does not appear to compete with arginine for transport through the hisP system, suggesting that the hisP protein may not be a "carrier" for these amino acids. The hisJ protein, a periplasmic histidine-binding protein, is known to function in conjunction with the hisP protein in the transport of histidine. The hisJ protein does not function with the hisP protein in arginine transport.


Genetic analysis of bacteriophage Mu-induced flagellar mutants in Escherichia coli. In previous work, at least 10 discrete cistrons involved in the synthesis of flagella in Escherichia coli were described. Six cistrons were located between his and uvrC on the genetic map. These were referred to as hag, flaA, flaB, flaC, flaD, and flaE. Four cistrons referred to as mot, flaG, flaH, and flaI were located between uvrC and aroD. In order to determine whether these genes are organized into transcriptional units, a series of Mu phage-induced flagellar mutants was studied. The mutant strains behaved as if they were carrying strong polar mutations. Of 228 independent Mu-induced mutants, 114 with mutations in the his-aroD region of the genetic map were tested by preparing partial diploid strains with episomes carrying a variety of previously defined mutations. The pattern of complementation that emerged indicated that cistrons flaB, flaC, and flaE form a transcriptional unit. Cistron flaO, defined in the course of this study, is also a member of this transcriptional unit. The order of transcription is B-C-O-E. flaA was found to be complex, and it included four cistrons, flaA, flaP, flaQ, and flaR, with the transcriptional order A-P-Q-R. Cistrons flaG and flaH are cotranscribed with the transcriptional order G-H. The remaining genes, flaD, flaI, hag, and mot do not belong to multicistronic transcriptional units. Complementation analysis suggested that the cheC locus is the same as cistron flaA.


Transport systems for alanine, serine, and glycine in Escherichia coli K-12. At least two transport systems serve for the entry of alanine, glycine, and serine into Escherichia coli. One of these systems serves mainly for glycine, d-alanine, and d-serine and to some extent for l-alanine, whereas the second serves for l-alanine and perhaps l-serine. These two transport systems have been characterized by kinetic studies and by inhibition analysis. Reciprocal plots for l-alanine entry are distinctly biphasic, giving rise to K(m) values of about 2 and 27 muM. The major route of glycine entry can be described by a single K(m) value of about 4 muM. A higher K(m) value for glycine of around 70 to 100 muM shows that other routes of entry may serve at high concentrations of amino acid. The glycine, d-serine and d-alanine transport system is defective in a d-serine-resistant mutant, strain EM1302. The mutation, dagA, is recessive in dagA/dagA(+) merodiploids and is 7 to 12% linked by phage P1 transduction to the pyrB locus of E. coli. E. coli with the dagA mutation are unable to utilize d-alanine as a carbon source, providing an additional basis for selecting such mutants. The remaining l-alanine uptake in dagA mutants is subject to inhibition by l-serine, l-threonine, and l-leucine. It is also sensitive to osmotic shock treatment and repressed by growth of the cells on l-leucine. It appears from a comparison of the properties of the second l-alanine system with those of the leucine, isoleucine, and valine system (LIV system) that the LIV system also serves for the transport of l-alanine and l-threonine and perhaps l-serine.


Studies on beta-galactoside transport in a Proteus mirabilis merodiploid carrying an Escherichia coli lactose operon. Merodiploid derivatives bearing an F-linked lac operon (i(+), o(+), z(+), y(+), a(+)) from Escherichia coli were prepared from a Proteus mirabilis strain unable to utilize lactose and from a lac deletion strain of E. coli. A suitable growth medium was found in which the episomal element in the P. mirabilis derivative was sufficiently stable to allow induction of the episome-borne lac operon and thus to permit a comparison of the activities and properties of E. coli lac products in the intracellular environments of P. mirabilis and E. coli. In both derivatives the episomal lac operon was shown to be repressed in the absence of inducer. Kinetics of induction with gratuitous inducer (isopropyl-1-thio-beta-d-galactoside) were similar for both beta-galactosidase activity (beta-d-galactoside galactohydrolase, EC 3.4.1.23) and beta-galactoside transport activity in both derivatives, although the ratio of galactoside transport to beta-galactosidase activity was approximately 1.6-fold higher in the E. coli derivative. Comparison of beta-galactosidase and M-protein (lac y gene product)-specific activities indicated coordinate expression of the induced lac operon in both derivatives. Quantitatively, the maximal beta-galactosidase specific activity was two or three times higher for the E. coli derivative. A significant sodium azide inhibition (65% inhibition by 10 mM sodium azide) of lactose permease-mediated transport of o-nitrophenyl-beta-galactoside from an outside region of high concentration to an inside region of very low concentration ("downhill transport") was observed for the P. mirabilis derivative. Identical conditions for the E. coli derivative yielded only about 15% inhibition. Active transport of thiomethyl-beta-galactoside was similar for both derivatives, the major difference being that active transport was more sensitive to azide poisoning in the P. mirabilis derivative. Preliminary examination of the thiomethyl-beta-galactoside derivatives following active transport did not demonstrate the accumulation of a phosphorylated product in either strain but did reveal an unidentified derivative present in the P. mirabilis merodiploid extract which was not detectable in the E. coli merodiploid.


Plasmids of Shigella dysenteriae Y6R: a defective Col factor. The six plasmids of Shigella dysenteriae Y6R were separated by sucrose gradients into five fractions containing deoxyribonucleic acid (DNA), having contour lengths (expressed in units equal to the fraction of the length of the replicative form of phiX174), respectively, of 0.29, 0.35, 0.74, 1.08, and a mixture of 5.7 and 7.2. DNA-DNA hybridization on nitrocellulose filters between each of the plasmids and between plasmid-free S. dysenteriae Y6R host DNA and plasmids was investigated. There was a high degree of homology between the 0.29- and 0.35-unit plasmids. No significant homology was found between any of the other pairs of plasmids. Homologous DNA to the extent of 2.4 copies of the 1.08-unit plasmid was found in the host genome. Homology between the other plasmids and the host genome is very slight, but appears to be significant. About 0.7 of the 1.08-unit plasmid is homologous to the ColE1 façtor of Escherichia coli JC411 (ColE1). This plasmid may be defective ColE1 factor with the immunity function intact, but with a defect in the gene leading to the production of active colicin. Electron microscope examination of heteroduplexes formed between the two smallest plasmids and between the 1.08-unit plasmid and the ColE1 factor yielded independent determinations of the extent of homology in agreement with the values determined by hybridization. In the latter case, two nonhomologous regions of substitution of DNA were detected.


Evidence for the control by exrA and polA genes of two branches of the uvr gene-dependent excision repair pathway in Escherichia coli K-12. A polA1 exrA strain of Escherichia coli K-12 was found to be more sensitive to ultraviolet radiation than the closely related polA1 or exrA strains, but not as sensitive as either the exrA uvrB or recA strains. The exrA and polA1 mutations both resulted in a deficiency in the repair of single-strand breaks arising in the deoxyribonucleic acid as a result of the excision repair process (incision breaks). These deficiencies were at least partially independent since the double mutant, polA1 exrA, was more deficient than a strain containing either the polA1 or exrA mutation alone. These results suggest that the polA1 and exrA mutations result in defects in two different branches of the uvr gene-dependent excision repair process. The repair of incision breaks was still observed in the polA1 exrA strain after low exposures of ultraviolet radiation, suggesting the existence of a third branch of the excision repair process which is dependent on neither the polA nor exrA genes. The polA1 and polA1 uvrA strains were not deficient in post-replicational repair. The exrA strain was partially deficient in post-replicational repair, but the polA1 exrA strain was no more deficient than the exrA strain in this repair process. Thus, the increased ultraviolet irradiation sensitivity of the polA1 exrA strain relative to the polA1 and exrA strains appears to be related to the effect of the polA1 and exrA mutations on different branches of the uvr gene-dependent excision repair process as well as to the effect of the exrA mutation on the post-replicational repair process.


Induction of unbalanced growth and death of Streptococcus sanguis by oxygen. Streptococcus sanguis has normal streptococcal morphology when grown in a nitrogen atmosphere but undergoes gross morphological alterations when grown in the presence of oxygen (O cells). Studies were made of the relationship between the development of pleomorphism and the loss of viability which accompanied it in O cultures of S. sanguis. The development of pleomorphism appears to involve two events. The first step, or triggering event, occurs in log-phase cultures in the presence of oxygen. The second step, or manifestation of pleomorphism, occurs at stationary phase in the presence or absence of oxygen. The loss of viability appears to be related both to the length of time the culture is exposed to oxygen as well as to a specific event which occurs at the transition from log to stationary phase. Oxygen also induced a state of unbalanced growth in S. sanguis in which the proportions of deoxyribonucleic acid, ribonucleic acid, and protein synthesized were altered. The relationship of these alterations to the development of pleomorphism is discussed.


Genetic analysis of thr mutations in Salmonella typhimurium. Previous workers divided threonine-requiring (Thr(-)) strains of Salmonella into three phenotypes with mutations in four complementation groups. The mutations were deemed to define four genes in the order thrD-C-A-B at minute zero on the Salmonella linkage map. In the present study 12 of these mutants were reexamined together with eight new Thr(-) strains. The three phenotypes were: homoserine-requiring (Hom(-)); Thr(-), feeders of Hom(-) strains; Thr(-), nonfeeders. Exact correlation between these phenotypic groups and three complementation groups was confirmed by abortive transduction. No evidence was found for intergenic complementation between mutations in Hom(-) strains. It is proposed that thr mutations define three genes rather than four and that these be renamed thrA (Hom(-)), thrB (Thr(-) feeders), and thrC (Thr(-) nonfeeders) to correspond with the sequence of reactions in threonine biosynthesis. Double mutant trpRthr strains were used in reciprocal three-point transduction tests to establish the order of thr mutation sites. Although revisions were made in the classification or location of several mutations, there was an overall correlation of complementation group, phenotype, and map position. The present data provide a basis for further correlation of threonine genes and biosynthetic enzymes, and analysis of cross regulation in aspartate amino acid biosynthesis in Salmonella.


Energy coupling of the hexose phosphate transport system in Escherichia coli. The active transport of hexose phosphates in Escherichia coli was inhibited by many uncouplers or inhibitors of oxidative metabolism. Fluoride and the lipid soluble cation, triphenylmethylphosphonium, had little effect. The uninduced level of transport was sensitive to fluoride, but not to azide. After energy uncoupling of active transport, the cells could equilibrate their intracellular water with the glucose-6-phosphate in the medium and displayed exit counter-flow suggesting the existence of carrier-mediated transport in the energy-uncoupled cells. The uncoupled transport of glucose-6-phosphate was inhibited by fructose-6-phosphate; the uninduced level of glucose-6-phosphate transport was not inhibited by fructose-6-phosphate. After energy uncoupling, the influx had a low affinity suggesting that, unlike the transport of beta-galactosides, the energy coupling for the active transport of hexose phosphate involved a change in the affinity of influx.


Turnover of phosphatidylglycerol in Escherichia coli. In growing cultures of Escherichia coli, the nonacylated glycerol of phosphatidylglycerol (PG) is labeled more rapidly than is the acylated glycerol. This is, in part, due to a rapid exchange reaction of the nonacylated glycerol. Only some of the PG molecules undergo this reaction while others are stable. Using a mutant unable to make glycerophosphate, we have shown that the nonacylated glycerol of PG can exchange with non-phosphorylated glycerol.


Cell growth and division in Escherichia coli: a common genetic control involved in cell division and minicell formation. Escherichia coli Div 124(ts) is a conditional-lethal cell division mutant formed from a cross between a mutant that produces polar anucleated minicells and a temperature-sensitive cell division mutant affected in a stage of cross-wall synthesis. Under permissive growth temperature (30 C), Div 124(ts) grows and produces normal progeny cells and anucleated minicells from its polar ends. When transferred to nonpermissive growth temperature (42 C), growth and macromolecular synthesis continue, but cell division and minicell formation are inhibited. Growth at 42 C results in formation of filamentous cells showing some constrictions along the length of the filaments. Return of the filaments from 42 to 30 C results in cell division and minicell formation in association with the constrictions and other areas along the length of the filaments. This gives rise to a "necklace-type" array of cells and minicells. Recovery of cell division is observed after a lag and is followed by a burst in cell division and finally by a return to the normal growth characteristic of 30 C cultures. Recovery of cell division takes place in the presence of chloramphenicol or nalidixic acid when these are added at the time of shift from 42 to 30 C, and indicates that a division potential for filament fragmentation is accumulated while the cells are at 42 C. This division potential is used for the production of both minicells and cells of normal length. The conditional-lethal temperature sensitive mutation controls a step(s) in cross-wall synthesis common to cell division and minicell formation.


Methionine limitation in Escherichia coli K-12 by growth on the sulfoxides of D-methionine. The synthesis and resolution of the diastereoisomers of d-methionine sulfoxide in high yield is described. Growth of two methionine auxotrophs (strains HfrC and AB1932) on the d-methionine sulfoxides is slower than on l-methionine, and the resultant cells are markedly derepressed for three enzymes of the methionine regulon (cystathionine synthetase, cystathionase, and S-adenosyl-l-methionine synthetase). Strain HfrC grows more rapidly on the sulfoxides and shows less derepression than strain AB1932. Although growth on d-methionine-d-sulfoxide is much slower than on d-methionine-l-sulfoxide (two- to threefold increase in division times), cells grown on d-methionine-l-sulfoxide generally have higher enzyme activities. The sulfoxides of d-methionine appear to provide a useful supplement to obtain methionine-limited growth in Escherichia coli.