Biomedical subjects
Publications and source records attributed to J M Schmidt.
A case of mycosis fungoides (MF) that began with cutaneous eritemato-papular lesions leading to death with neurological symptoms is reported. Cutaneous histophatology was typical to MF and the liquoric citology showed Sézary cells. Necropsy evidenced extra-cutaneous dissemination of the tumor involving lymphnodes, heart, digestive system, bladder, liver, bone marrow and leptomeninges. The uncommon clinical manifestations and evolution are discussed.
When grown in a complex peptone-yeast extract culture medium, Seliberia stellata and related morphologically similar aquatic bacterial strains typically divided asymmetrically, giving rise to a motile swarmer and a longer sessile rod. Indirect immunoferritin labeling of these bacteria, followed by incubation during which cell growth occurred, has provided evidence that antigenic cell-surface components are synthesized de novo in a sharply demarcated zone at one pole of the growing parent cells. Cell elongation occurred unidirectionally from the pole showing the de novo surface synthesis; it was this end of the elongating, helically sculptured (i.e., screw-like) rod that became the daughter swarmer cell. The daughter swarmers, produced after polar growth and division of the immunoferritin-labeled parent cells, were not labeled. The immunoferritin label remaining on the parent cell did not appear to be diluted or disturbed by the cell growth and division process. Under the cultural conditions used in this study, the growth and division events which led to production of swarmer cells in the seliberia strains examined met two major criteria of accepted definitions of budding (de novo cell surface synthesis and transverse asymmetry of division). However, the developing daughter cell was not initially narrower than the parent and thus did not increase in cell diameter during growth.
The lower mean cell age and prolonged 51Cr-labeled red cell survival of the top layer of centrifuged red blood cells suggest that this product may reduce blood requirements in patients with transfusion-dependent anemias. In a prospective clinical trial, we compared the effect of regular administration of young red cells with that associated with use of conventional frozen cells. Six patients with thalassemia major received 192 units of young red cells prepared from single donor units of whole blood using the IBM 2991 Cell Processor. The mean transfusion requirement to maintain the hemoglobin level greater than 9.0 gm/dl was 110 +/- 17 ml RBC/kg during the year of young cell transfusions, in comparison with 130 +/- 20 and 131 +/- 23 ml RBC/kg when conventional frozen cells were administered in the years before and after the young cell trial, respectively. Blood requirements in individual patients were reduced by 8% to 24% (mean 15.8%); the hemoglobin level remained constant. Although young cells of consistent quality can be prepared regularly in a clinical setting with little difficulty, the cost of the product is high and the effect on transfusion requirements is less than predicted from studies in vitro and from labeling experiments.
The authors report two cases of temporal arteritis complicated with dissecting aneurysm of the aorta. The first one is discovered on systematical physical examination, the second is revealed by a thoracic pain. Clinical course is favourable under steroid therapy in both cases. Eleven cases of such complication with pathological control are reported in literature. Physiopathological mechanisms are discussed and active inflammatory involvement of aortic wall seem to be the main cause.
The elderly often presents loss of Achilles tendon reflex. In this electrophysiological study the authors examined 19 patients with loss of the ankle jerk and with no known etiology of peripheral neuropathy. They compared them with 24 subjects who had no areflexia. The study included measurement of the H reflex, of the tendon reflex, of the conduction velocity of Ia fibers and of motor conduction velocity of the tibial nerve. Amplitude of H and tendon response and H/M ratio are diminished in the areflexic group. In 4 cases the H reflex is preserved while the tendon reflex is abolished. The meaning of these impairments is discussed.
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A culture of P388 murine lymphoblastoid cells has been shown to contain type C oncornavirus-like particles budding at the plasma membrane. Occasionally intracytoplasmic type A and immature type B particles were also observed by electron microscope techniques. The discovery of oncornavirus-like particles in the P388 cell line increases the utility of this neoplastic system for detecting potential antineoplastic agents.
Ten Beagle pups were each inoculated per os with 2,000 tetrathyridia of Mesocestoides corti from mice. The dogs were necropsied at 5-day intervals and the small intestine of each dog was divided into 3 equidistant sections. Adult cestodes were counted and characterized morphologically. The M corti reproduced asexually in the Beagles by longitudinal splitting of the parent scolex, separation of a new individual, and subsequent regrowth of 2 additional suckers on both the parent and newly formed scolices. Five days after the tetrathyridia were given, evidence of parent scolex division was present. The ability of M corti to reproduce asexually in the definitive host enabled rapid proliferation of new organisms, with approximately 53,000 present 45 days after inoculation.
Exertional rhabdomyolysis is a condition arising in several species of newly captured wild animals after some form of physical exertion and stress. It is characterized by muscle necrosis and myoglobinuria. Death may result from secondary renal failure, acute or chronic heart failure and progressive emaciation.
The cellular fatty acid composition of 14 strains of Caulobacter speices and types, two species of Prosthecomicrobium, and two species of Asticcacaulis was determined by gas-liquid chromatography. In most of these bacteria, the major fatty acids were octadecenoic acid (C18:1), hexadecenoic acid (C16:1) and hexadecanoic acid (C16:0). Some cyclopropane and branched chain fatty acids were detected in addition to the straight chained acids. Hydroxytetradecanoic acid was an important component of P.enhydrum but significant amounts of hydroxy acids were not detected in other prosthecate bacteria examined.
Triton X-treated prosthecae from Asticcacaulis excentricus and A. biprosthecum were sonicated and examined with a electron microscope. Crossbands had a substructure of concentric rings and were digested by lysozyme.
Estimates of average rates of stalk formation over several generations of growth in Caulobacter crescentus showed that long-stalked Sk1 mutant and phosphate-starved wild-type cultures produce stalk material at about twice the rate of wild-type C. crescentus grown with adequate nutrients. Thus, the long stalks of Sk1 or phosphate-starved caulobacters are not merely a function of their longer doubling times. Inhibition of cell division of Sk1 418 with mitomycin C (MC) caused production of cellular filaments and resulted in inhibition of stalk formation. There was no appreciable decrease in total cell mass or in rates of ribonucleic acid and protein synthesis in the MC-treated cultures as compared with controls, but stalk formation, which is normally dependent on these processes, was severely retarded. Average stalk lengths in MC-treated Sk1 cultures were 30% of those found in control cultures. MC-produced cellular filaments were also subjected to deoxyribonucleic acid analysis and ultrastructural examination. The deoxyribonucleic acid content of MC-treated bacteria was about 50 to 60% that of untreated bacteria. Hydroxyurea also was found to produce some cellular filaments and shorter stalks, but with accompanying decreases in growth rate and yield.
An ultrastructural study of crossbands isolated from Caulobacter crescentus Sk1 418 stalks permitted a view of these structures in a plane other than the perpendicular view normally presented in the electron microscope. These crossbands were composed of concentrically arranged, alternating light and dark bands when stained with phosphotungstic acid. Evidence supports the hypothesis that crossbands appear to compose a structural barrier extending the width of the stalk and may function to support unit membrane extending the length of the stalk.
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Extensive stalk elongation in Skl mutants of Caulobacter crescentus occurs when they are grown in complete medium. This stalk elongation is less pronounced in synthetic medium with glucose as the sole carbon source than in complex peptone yeast extract medium. Addition of exogenous nucleoside triphosphates (adenosine triphosphate [ATP], guanosine triphosphate [GTP], cytidine triphosphate, and uridine triphosphate) inhibits stalk elongation of the Skl mutants, whereas cyclic guanosine 3',5'-monophosphate (GMP) stimulates stalk elongation in the Skl strains grown in synthetic glucose medium. Cyclic GMP also produces stalk elongation in wild-type C. crescentus and concurrently produces a cell division defect resulting in cellular filament formation. Under conditions tested, cyclic adenosine 3',5'-monophosphate and dibutyryl cyclic adenosine monophosphate did not enhance stalk elongation. Endogenous ATP and GTP levels in the mutants are significantly lower than corresponding nucleotide concentrations of the parent wild-type strains. Control of syntheses resulting in stalk formation in C. crescentus appears to be related to intracellular concentrations of nucleotides, with cyclic GMP as a prominent candidate for an important regulatory role in this aspect of morphogenesis.
Limitation of inorganic phosphate in the culture medium allows stalk elongation in wild-type Caulobacter crescentus. Mutants unable to form long stalks were isolated.