Detection and estimation of azomethane in expired air of 1,2-dimethylhydrazine-treated rats

Azomethane (AM) gas was identified as a major metabolite of 1,2-dimethylhydrazine (1,2-DMH) in the expired air of F344 rats. The compound was characterized by high-pressure liquid chromatography, gas chromatography, and mass spectrometry, in comparison to a synthetic standard. At a dose of 21 mg 1,2-DMH/kg sc, approximately 14 and 11% of the dose were exhaled as AM and CO2, respectively, in 24 hours. At 200 mg 1,2-DMH/kg, 23 and 4% of the dose appeared as AM and CO2, respectively, in the respired air within the same period. Most AM was seen in the first 6 hours, but the CO2 evolution was more progressive, especially after the higher dose of 1,2-DMH.     

Common complications of vaginal hysterectomy: thoughts regarding their prevention and management

Quantitative estimates were computed for exponential coefficients and rate constants contributing to afferent unit impulse responses obtained from bundles innervating specific regions of the semicircular canal. The grouping of these estimates into specific response classes provided quantitative correlations with specific anatomical regions of innervation of the crista. Linear system gain and phase spectra were computed also, by applying Fourier transformations to unit impulse responses, for purposes of comparison with previous studies employing frequency domain analyses. Responses fitted by third-order linear system equations were specific to afferents innervating the crest and transition regions of the crista; whereas those fitted by overdamped, second-order equations were specific to afferents innervating the slopes and transition crista regions. It was concluded that strictly mechanical models of the transduction process are inadequate to account for the diverse and spatially distributed classes of observed responses and, moreover, structural features such as different hair cell types or efferent innervation effects could be excluded as inoperative in this preparation. The alternative hypothesis was suggested that certain of the observed subcomponents could be direct reflections of the initial mechanical stimulus, but that other subcomponents were reflections of more complex filtering mechanisms operating at the cellular or synaptic levels.     

Changes in the hatch rate of Haemonchus contortus eggs between geographic regions

Vulvar phenotypes and the rate of development of eggs over a range of temperatures were used to compare Haemonchus contortus populations in New York State and Ohio. These parameters indicated that the westernmost boundary of the subspecies Haemonchus contortus cayugensis is the Chautauqua valley in New York. The Haemonchus ecotype in Ohio had a vulvar phenotype formula similar to that described for the subspecies Haemonchus contortus contortus. The relationship between slope and intercept of the regression of rate of egg hatch on temperature was different for morphs within ecotypes as well as between the New York and Ohio ecotypes. Linguiform-A appeared to be the cold-adapted morph in both ecotypes. Smooth was the warm-adapted morph in New York with linguiform-B filling that niche in Ohio.     

Striated muscle in the pineal gland of swine

Striated muscle fibers (or cells) were observed in three of the six swine pineal glands. The muscle fibers occurred in clusters of several fibers about the parenchymal blood vessels. They were in general poorly developed, lacked regular cross striations and were not readily recognized histologically. The muscle fibers were, however, easily identified on electron microscopy because of the myofilaments they contain. In most of the muscle fibers, the myofilaments were arranged in ill-defined, disorderly bundles and rarely formed well-defined myofibrils and sarcomeres. The sarcotubular system was also poorly developed and triads were sparse and randomly scattered. Leptomeres were observed in several muscle fibers. The source of the muscle fibers in the pineal glands is not well understood and, whatever the source may be, the muscle fibers seem to remain poorly developed in the pineal glands.     

Outpatient chemotherapy of advanced breast cancer in a community setting: a five-drug regimen

Forty-two (37 evaluable) unselected women with advanced breast carcinoma were treated with a modified "Cooper regimen" in a community setting. After 12 weeks of induction therapy, the patients were evaluated for response and toxicity. The 74% overall response rate (78% in the evaluable group) compares favorably with that of other series. The median duration of remission was 13.7 months. The median survival was 17 months for the evaluable patients and 14 months for the entire group. Twenty-two percent of the patients required hospitalization during the induction phase, and 35% were treated exclusively as outpatients during all phases of therapy. There was only one drug-related death. It is concluded that a complex chemotherapeutic regimen can be managed adequately by physicians experienced in chemotherapy in a community setting with results comparable to those from cancer centers.     

Bacteriophage MX-1: properties of the phage and its structural proteins

Bacteriophage MX-1 is a virulent DNA phage for Myxococcus. The host range includes strains of Myxococcus xanthus, M. fulvus and M. virescens. The phage has a sedimentation coefficient (S degrees 20,w) of 1145S and a density of 1-531 g/ml. By using SDS-polyacrylamide gel electrophoresis, 23 phage proteins with apparent mol. wt. between 10000 and 150000 were resolved. Gel filtration in the presence of non-ionic detergent partially resolved the proteins. The fraction excluded from Sephadex G-100, fraction 1, contains two glycoproteins. Fraction 1 was resolved into three fractions (1-1, 1-2 and 1-3) by chromatography on Sephadex G-200. The glycoproteins were present in fraction 1-2; all the proteins from this fraction were derived from the phage tail. Comparison of the amino-acid, hexosamine and neutral-sugar compositions of the two glycoproteins showed that they are distinct molecular species; the smaller molecule is not a subunit of the larger. The significance of these findings is discussed and compared with the proteins of the tails of T-even phage of Escherichia coli.     

Transureteroureterostomy for urinary diversion in children

We report here a model of submaximal spinal cord injury, employing direct thoracic cord compression in ferrets. This yields consistent and reproducible long term consequences on local cellular structure and on locomotive function. We show also that both the anatomical and functional losses can be measured objectively using simple techniques, and that useful long-tract mediated locomotion is preserved after severe axonal losses at the site of injury.