Showing papers by "University of Vermont published in 1977"
TL;DR: In this paper, the authors classify the possible causality relationships between two series X and Y, using an analogy to events in a sample space, and present some new results on alternative characterizations of the more important causality events.
638 citations
TL;DR: There is evidence that renal prostaglandins are involved either primarily or secondarily in many types of hypertension, and inhibitors of prostaglandsin cyclooxygenase have been used with success in Bartter's syndrome.
Abstract: This review provides a summary and assessment of research involving renal prostaglandins. Arachidonic acid released from phospholipids is converted by prostaglandin cycle-oxygenase in the kidney to...
374 citations
TL;DR: A thorough understanding of the ways in which the lung protects itself against the daily assault of infectious, toxic, and immunogenic materials should lead to a beter understanding of pathogenesis and consequences of lung disease and to better clinical care of the patient with respiratory disease.
Abstract: The success or failure of pulmonary defense mechanisms largely determines the appearance of clinical lung disease. The lung is protected by interlucking systems of nonspecific and specific defenses. Inhaled substrances can be isolated by mechanical barriers or can be physically removed from the lung either by transport up the bronchial mucociliary escalator or by transport through interstitial and lymphatic channels leading to lymph nodes. Substances can be locally detoxified within the lung by interaction with secretory proteins, such as antibodies, or by neutralization and dissolution within phagocytic cells. The pulmonary alveolar macrophage is the central figure in the protection of the respiratory membrane, operating in all 3 of the nonspecific modes of defense and augmented by specific immunologic mechanisms as well. Alterations in macrophage function and physiology may be crucial in determining the effectiveness of pulmonary defense. Recent advances in the cell biology of the alveolar macrophage have led to a greater understanding of its complex funcition. The multiple origins of macrophages from local and circulating cell pools and the variability in their fate and lifespan reflect the multi-faceted role of this cell type. The importance of the interactions between macrophages, orther lung cells, and other defense mechanisms has become increasingly clear. As well as functioning as resident defender of the alveolus, the macrophage is an important effector of the pulmonary immune response and plays a key role in the pathogenesis of a wide variety of inflammatory, destructive, and fibrotic lung diseases. Humoral and cell-mediated immune responses amplify and direct lung defenses against infection and may also participate in protection against other agents. Immunoglobulin A and G, microbial neutralizing and opsonizing anti-bodies, and macrophage-stimulating T lymphocytes are the major immunospecific forms of lung defense. Infectious agents, cigarette smoke, air pollutants, industrial dusts, and a spectrum of coexistent disease states may impair pulmonary defense mechanisms and increase susceptibility to asute and chronic respiratory diseases. A thorough understanding of the ways in which the lung protects itself against the daily assault of infectious, toxic, and immunogenic materials should lead to a beter understanding of pathogenesis and consequences of lung disease and to better clinical care of the patient with respiratory disease.
338 citations
TL;DR: A two-stage identification procedure is presented which involves fitting univariate time-series models to each series, and identifying a dynamic shock model relating the two univariate model innovation series.
Abstract: A methodology is introduced for identifying dynamic regression or distributed lag models relating two time series. First, specification of a bivariate time-series model is discussed, and its relationship to the usual dynamic regression model is indicated. Then, a two-stage identification procedure is presented which involves fitting univariate time-series models to each series, and identifying a dynamic shock model relating the two univariate model innovation series. The models obtained at these two stages are combined to identify a dynamic regression model, which may then be fitted in the usual ways. Two systems of economic time series illustrate the methodology.
256 citations
TL;DR: The results support a role for an amygdala beta-adrenergic system in memory processes and time-dependent and dose-dependent decreases in retention of the task.
Abstract: beta-Adrenergic antagonists injected into the amygdala complex of rats trained in a passive avoidance task produced time-dependent and dose-dependent decreases in retention of the task. In addition, the effects observed with beta-adrenergic antagonists were both stereospecific and reversed by norepinephrine. The results support a role for an amygdala beta-adrenergic system in memory processes.
195 citations
TL;DR: Observations suggest that changes in potassium modulate ammonia production, which in turn maintains hydrogen ion homeostasis and influences potassium excretion, and potassium-loading affects different portions of the renal tubule than depletion does.
128 citations
TL;DR: The clinical toxicology, clinical pharmacology, and therapeutic effects of bleomycin given by continuous intravenous infusion were studied in patients with far‐advanced unresectable cancer; useful therapeutic responses were seen in a variety of tumors.
Abstract: The clinical toxicology, clinical pharmacology, and therapeutic effects of bleomycin given by continuous intravenous infusion were studied in patients with far-advanced unresectable cancer. The toxicity of bleomycin given by that schedule was qualitatively and quantitatively the same as when it was given by daily intravenous "push"; mucocutaneous toxicity occurred regularly after 7-11 days of infusion. Careful monitoring of pulmonary function revealed minor changes in Total Lung Capacity and Pulmonary Diffusion Capacity in nearly all patients; however, overt pulmonary toxicity occurred in only six patients (5%). 111Indium-labeled bleomycin was used to follow blood levels of bleomycin; it correlated well with the levels determined by microbiologic assay and could be measured at levels lower than could be determined by bioassay. Useful therapeutic responses were seen in a variety of tumors; 30% patients with very far-advanced carcinoma of the cervix demonstrated CR or PR, an incidence higher than has been seen with other regimens. Sixty-nine percent of patients with disseminated germ cell neoplasms of the testis, refractory to bleomycin given by conventional dose schedules, have attained partial remission through the continuous infusion of bleomycin.
119 citations
TL;DR: The shoulder, a very common site of pain syndromes in medical practice, lends itself well to precise clinical analysis and identification of the pain-sensitive structure or structures, once identified, rational and effective management can be applied, associated with predictably good prognosis.
112 citations
TL;DR: The evidence presented suggests that diphtheria toxin-resistant variants selected from Chinese hamster ovary cells are translational variants possessing a mutationally altered EF-2 gene product, and that Pseudomonas toxin ADP-ribosylatesEF-2 in toxin-sensitive intact cells, as well as in cell-free systems.
96 citations
TL;DR: Chlorella pyrenoidosa is capable of concentrating cadmium, and the amount accumulated is directly proportional to the concentration of metal present initially and is dependent upon the pH of the medium.
91 citations
TL;DR: Compared pre- and posttreatment performances on the Halstead-Reitan neuropsychological battery of 20 patients who were receiving ECT from two different machines, most Ss gave indicators of cerebral impairment prior to treatment and after treatment, there was an increased number of Ss who evidenced signs consistent with damage to the right cerebral hemisphere.
Abstract: Although ECT as the treatment of choice for psychotic depression has been in use for many years, little is know about the neocortical residual of such treatents inferred from behavoioral measures. The major portion of the literature has been concerned with inferred or observed changes in affective state. The presents study compared pre-and posttreatment performances on the Halstead-Reitan neuorpsychological beattery of 20 patients who were receiving ECT from two different machines, Most Ss gave indicators of cerebral impariment prior to treatment when performance of one side of the body was contrasted with performance of the other side. After treatment there was an incresed number of Ss who evidenced signs consistent with damage to the right cerebral hemisphere. Some conceren was raised that a large number of patients who eventually are subjected to ECT because of depression behave in this way because of an undiagnosed neocortical dysfunction. There is some suggestion that the effect of the procedure is to either create or intenisfy right hemispher focus as inferred from behavioral measures.
TL;DR: When the sealant remained intact, there was a pronounced reduction in caries initiation--the percent effectiveness being 84%.
Abstract: The single application of a pit and fissure sealant was fully retained on 50%of all paired permanent teeth at the 48-month examination. When a sealant is completely retained at the 50% level and for each child an average of 2.7 teeth is saved, pit and fissure sealants must be considered an essential preventive dentistry measure for children. The actual number of teeth estimated to be saved from caries was 23 per 100 with a positive treatment benefit for 69% of the children in the four-year study. Results of examinations at 12, 36, and 48 months showed sealant retention on first premolars and molars was superior to that on second premolars and molars.
TL;DR: Since the reduction of postexposure rabies vaccination to seven doses, no new cases have been observed in Colombia, and Pathologically, this was shown to be a typical polyradiculoneuritis.
Abstract: • Twenty-one cases of neuroparalytic accidents of rabies vaccination (with suckling mouse brain vaccine), 11 of them fatal, were observed, occurring predominantly in men; the mean age of the patients was 29 years. On the average, 13 doses of the vaccine were used. Only three patients received less than seven doses. The mean latent period was 14 days (range, 4 to 24 days). In 16 patients (76%), a Guillain-Barre syndrome occurred that was moderate in three, severe in seven, and fatal in six. Pathologically, this was shown to be a typical polyradiculoneuritis. Five patients had fatal involvement of the central nervous system. Three had an acute disseminated perivenous leukoencephalopathy, with concurrent rabies encephalitis in one case. One patient had a perivenous myeloradiculopathy and one a chronic encephalomyelopathy of six years' duration with demyelinating plaques in the periventricular white matter, cerebellum, and spinal cord. Since the reduction of postexposure rabies vaccination to seven doses, no new cases have been observed in Colombia.
TL;DR: It is concluded that women experience an unacceptably high incidence of side effects from minocycline, and this may be related to their higher serum concentrations, which in turn may relate to their smaller size.
Abstract: We studied the incidence and type of side effects of minocycline in a double-blind study. A total of 45 volunteers (18 men and 27 women) were given minocycline, and 44 volunteers (23 men and 21 women) were given placebo. The men in both the minocycline and placebo groups were significantly (P < 0.0001) larger than the women in the comparable groups. Minocycline dosage was 100 mg every 12 h for 5 days, and placebo was administered in an identical manner. Minocycline serum concentrations were determined in 12 volunteers at 1, 2, 4, and 6 h after the morning doses on days 1, 3, and 5 of the study. Side effects were recorded by volunteers in diaries and also through daily interviews and were evaluated by examination and electronystagmography. Peak minocycline serum concentrations were seen by day 3 and correlated with the peak onset of side effects. These concentrations were significantly higher in women than in men. Vestibular side effects occurred in 70.4% of the women on minocycline and significantly (P < 0.0001) exceeded the rate of the women on placebo (9.5%). Only loss of balance was significantly (P < 0.05) increased in the men taking minocycline as contrasted with men on placebo. Electronystagmography generally revealed no abnormalities. Side effects were usually not severe: four volunteers in the minocycline group and two in the placebo group discontinued their capsules because of side effects. It is concluded that women experience an unacceptably high incidence of side effects from minocycline, and this may be related to their higher serum concentrations, which in turn may relate to their smaller size.
TL;DR: Characterisation of the virus responsible has been completed and indicates that it is an R.N.A. virus, 55-60 nm in diameter, heat, ether, and acid stable, and antigenically related to Nebraska calf-diarrhoea virus, which belongs to the Reoviridae family.
TL;DR: The present set of experiments demonstrated that high-frequency reinforcement of alternative behavior during the first half of an extinction phase seems similar in effect to procedures which physically prevent rats from emitting the response programmed for extinction.
Abstract: One procedure which has been used to supplement extinction in order to produce faster and more complete response suppression is to provide reinforcement for some alternative response which is incompatible with the response undergoing extinction. When reinforcement for the alternative behavior is discontinued, however, substantial recovery of the original response has often been observed. The present set of experiments demonstrated that such recovery is best accounted for by a “response prevention” hypothesis rather than by a “discriminative cue” hypothesis. High-frequency reinforcement of alternative behavior during the first half of an extinction phase seems similar in effect to procedures which physically prevent rats from emitting the response programmed for extinction.
TL;DR: Sodium arsenate crosses the placental barrier in pregnant Syrian hamsters following injection in teratogenic or tracer doses on the 8th day of gestation.
Abstract: Sodium arsenate crosses the placental barrier in pregnant Syrian hamsters following injection in teratogenic or tracer doses on the 8th day of gestation.
TL;DR: In this article, partial thermodynamic parameters for hydrogen absorption are reported for palladium plastically deformed by the phase change, and they show that the absorption isotherms for hydrogen are similar to those exhibited by heavily cold-worked palladium.
Abstract: Following the α-β phase change in palladium, there is an enhanced solubility of hydrogen at a given equilibrium pressure within the low hydrogen content α phase. There are marked similarities between the absorption isotherms for hydrogen following the phase change and those exhibited by heavily cold-worked palladium. Partial thermodynamic parameters for hydrogen absorption are reported for palladium plastically deformed by the phase change.
TL;DR: This paper found that women tend to be less active in the political system than men, although that difference is often wiped out by controls for education, age, and region, and has been decreasing with time.
Abstract: Studies of sex differences in the political arena are often confined to those which are easily measured, particularly in the mass population, such as political participation, voting behavior, and political attitudes. There are a limited number of findings. First, women tend to be less active in the political system than men, although that difference is often wiped out by controls for education, age, and region, and has been decreasing with time (Verba and Nie, 1972). Second, sex rarely determines voting preference, except in aberrant cases (Campbell et al., 1960). Finally, women tend to be less hawkish and militaristic, although much of these data are limited to the Vietnam war (Pomper, 1975). These findings all indicate that sex is less important in determining political activity than race, class, income, or religion. Women are one of the few social groups that are not geographic &dquo;isolates&dquo;-women
TL;DR: In this article, the in vivo metabolism of 32P orthophosphate into chondroxyte, matrix vesicle, and membrane fractions of chicken epiphyseal cartilage has been studied.
Abstract: The in vivo metabolism of 32P orthophosphate into phospholipids of chondroxyte, matrix vesicle, and membrane fractions of chicken epiphyseal cartilage has been studied. Incorporation of radioactive phosphate into the total phospholipid fraction of matrix vesicles was rapid, the labeling of phosphatidylcholine and lysophosphatidylserine being even more rapid in matrix vesicles than in chondrocytes. These findings indicate that matrix vesicles are formed by a rapid, metabolically active process, and are not remnants of dead cells, as had previously been postulated by some workers. The rate of incorporation of 32P orthophosphate into phosphatidylserine and sphingomyelin of matrix vesicles was significantly slower than that of phosphatidylcholine and certain other vesicle phospholipids. These findings are paradoxical because, compared with chondrocytes, matrix vesicles were enriched in phosphatidylserine and sphingomyelin and depleted in phosphatidylcholine. These results indicate that in vesicle formation the rates of degradation of the various phospholipid classes must be markedly different: phosphatidylcholine must be degraded much more rapidly than either phosphatidylserine or sphingomyelin. Support for this comes from previous data which revealed that substantial phospholipase activity is present in epiphyseal cartilage, especially in the zone of hypertrophy where matrix vesicle formation appears to be particularly active.
TL;DR: The affinity of the antibody and the titer developed in the goat allowed the assay to be performed routinely with the use of a plasma sample size of only 2 to 5 µl, and was found to be highly specific for theophylline and sensitive to 2 ng.
Abstract: The use of theophylline in premature infants has necessitated the development of an assay applicable to samples under 0.1 ml. To accomplish this we have developed a radioimmunoassay for theophylline. The antiserum to theophylline has been characterized and found to be highly specific for theophylline and sensitive to 2 ng. The affinity of our antibody and the titer developed in the goat allowed the assay to be performed routinely with the use of a plasma sample size of only 2 to 5 micronl. Theophylline levels of 6 to 20 microng/ml were found 2 hr after maintenance doses of aminophylline, 4 mg/kg per rectum in 12 premature infants. Terminal serum half-lives ranged from 12 to 54 hr.
TL;DR: In this article, the authors compare the relative suppressive effects of two positive reinforcement procedures: reinforcement of a specific alternative behavior and omission training or differential reinforcement of other behavior (DRO).
TL;DR: The results emphasize the importance of nuclei in the metabolism of BP and in the subsequent alkylation of DNA, reactions which may be related to mutagenesis or carcinogenesis.
TL;DR: Leaves of the aquatic plant Elodea, which contain gas-filled intercellular channels, were irradiated at 1 MHz in pulsed and continuous modes and no structural changes were found in the organelles, as observed by electron microscopy in cells which had not been lethally injured.
Abstract: Leaves of the aquatic plant Elodea, which contain gas-filled intercellular channels, were irradiated at 1 MHz in pulsed and continuous modes. Morphological perturbations of the leaf cells include disruption of the parietal layer leading to cell death, when leaves are irradiated at spatial-and-temporal-peak intensities above a threshold Io. Although the cellular organelles are fragmented at intensities well above Io, no structural changes were found in the organelles, as observed by electron microscopy, in cells which had not been lethally injured. The presence of gas bodies prior to irradiation leads to values of Io below the threshold for cavitation and cell death in the absence of these bodies. For continuous-irradiation times t in the range 10−3 to 104sec, Io is proportional to t−0.29 and is about 2.4 W/cm2 for 1 sec irradiations. For pulsed irradiations, the effects of individual pulses accumulate to yield values of Io below those for single-pulse irradiations. The values of Io for pulsed irradiations are equal to, or greater than, those for continuous irradiations of equal total on-time.
TL;DR: It is concluded that, in women, a doses of 150 mg of minocycline per day is associated with the same degree of side effects as a dose of 200 mg per day.
Abstract: The incidence of side effects due to two dosage regimens of minocycline was examined over a 5-day period. A total of 60 normal women volunteers were randomly assigned in a double-blind manner to either a group who took 100 mg of minocycline twice a day or a group who took 75 mg of minocycline twice a day for 5 days. Both groups were comparable from the standpoints of age, size, race, and the use of oral contraception, nicotine, and ethanol. They were seen on a daily basis, and symptoms were evaluated by both volunteers (from diaries) and physicians. Minocycline serum concentrations were determined on blood samples taken 2 h after the a.m. dose. Volunteers taking 150 mg of minocycline per day had significantly lower serum antibiotic concentrations than those taking 200 mg per day. However, both low- and high-dose groups exhibited similar incidence and prevalence of recorded symptoms, with the single exception of nausea, where the low-dose group had fewer symptoms than the high-dose group (P = 0.035). Symptomatic volunteers did not have higher serum concentrations of minocycline than their asymptomatic counterparts. When either weight or surface area was examined with antibiotic serum concentration there was a significant inverse correlation between the two on day 2 for both groups and also on day 4 for the low-dose group. It is concluded that, in women, a dose of 150 mg of minocycline per day is associated with the same degree of side effects as a dose of 200 mg per day.
TL;DR: In this paper, the solution of hydrogen in PdCu fcc substitutional alloys has been examined in the region of low hydrogen contents and the relative electrical resistance relationship has been determined as a function of their hydrogen contents.
TL;DR: The morphology of the labeled and impregnated degenerating nerve fibers closely coincides with information provided by previous investigators using Golgi stained histological preparations and electron microscopy.
Abstract: This study identifies climbing fibers in the cerebellar cortex following brain stem lesions. Antegrade nerve fiber degeneration was studied after electrolytic destruction of rhombencephalic structures in 24 domestic fowl. Direct damage to the cerebellum was precluded by a retropharyngeal surgical approach. Only lesions that include the inferior olivary nucleus were compatible with Fink-Heimer staining of degenerating nerve fibers in the Purkinje cell and molecular layers. Degenerating axons were identified as climbing fibers from their trajectory in association with Purkinje cell soma and dendrites. Terminal nerve endings were observed only in the basal one-third to one-half of the molecular layer. The presence of climbing fibers in only the contralateral molecular layer was observed in autoradiographic preparations subsequent to unilateral injection of tritiated leucine into the inferior olivary nucleus of three hens. The morphology of the labeled and impregnated degenerating nerve fibers closely coincides with information provided by previous investigators using Golgi stained histological preparations and electron microscopy.
TL;DR: In this article, a simplified model of the orbit phenomenon is given by (2)1/2ps, where ps is the threshold pressure amplitude for rectified diffusion and has the value 0.18 bar.
Abstract: As observed microscopically, bubbles in a standing‐wave acoustic field move to the pressure nulls and oscillate, in elliptical orbits, about a common axis. The orbits of individual bubbles are equally spaced about 100 μm apart along the axis, forming a linear array. These arrays form in tap water for peak pressure amplitudes of 10–20 bar, but persist at levels as low as 1.5 bar. The 7‐μm diameter of the bubbles is approximately the theoretical size for resonant air bubbles in water driven at the 986 kHz frequency of the field. The radius of the orbits is approximately inversely proportional to the pressure gradient at the pressure null, with proportionality constant 0.25 bar. In a simplified model of the orbit phenomenon the expected proportionality constant is given by (2)1/2ps, where ps is the threshold pressure amplitude for rectified diffusion and has the value 0.18 bar. Calculations of ps, based on current theories for rectified diffusion, are in substantial agreement with the this value. The period ...