Search PubMed⌕ Search

Biomedical subjects

S Berman

Publications and source records attributed to S Berman.

At least 55 records · Page 3Linked to original sources
PubMed1989

Differential effects of cyclosporin on hepatic and renal heme, cytochrome P-450 and drug metabolism. Possible role in nephrotoxicity of the drug.

Treatment of rats with 25 or 50 mg/kg cyclosporin A for 6 days elicited vastly different responses in hepatic and renal heme and drug metabolism activities. In the liver, cytochrome P-450 concentration was decreased significantly (to 70-75% of the control). This was accompanied by a marked reduction in benzo[a]pyrene hydroxylase activity (to 20-28% of the control). Aniline hydroxylation was also decreased, but to a lesser extent (to 77% of the control). In contrast, in the kidney cytochrome P-450 concentration was significantly increased to (145-170% of the control), along with a modest decrease in benzo[a]pyrene hydroxylation activity. In this organ, the concentration of porphyrins was severely decreased (to 30% of the control). Also, the activities of delta-aminolevulinate (ALA) synthetase and ALA dehydratase, as well as that of heme oxygenase, were inhibited. It is suggested that in the kidney the inhibition of degradation, rather than an enhanced rate of synthesis of the heme molecule, contributes to the observed increase in cytochrome P-450 concentration. In the liver, the decrease in the cytochrome concentration could not be explained in terms of an alteration in the rate of heme biosynthesis or degradation. Therefore, the observed decrease in cytochrome P-450 concentration could reflect the direct inactivation of the hemoprotein or regulation of apoprotein production by cyclosporin and/or its metabolite(s). The possible relevance of the observations to cyclosporin nephrotoxicity is discussed.

Aniline Hydroxylase↗
PubMed1989

How residents cope with living near a hazardous waste landfill: an example of substantive theorizing.

It is hard to be a community or environmental psychologist and not be interested in newspaper stories on global warming, oil spills, or toxic wastes in your own backyard. To the general public, these issues tend to be viewed as environmental, technological, toxicological, or governmental, but not psychological. As psychologists, we see many ways in which psychology does play a role in understanding these events. We have been engaged in a study of residents living near a hazardous waste landfill in which many subdisciplines of psychology have played an illuminating role. Wicker's (this issue) article on substantive theorizing outlines an approach to theory and research that helps communicate the structure and process of doing research on a complex area. We use his article to help us describe key aspects of our research that are not usually discussed in research articles. We believe that the type of research Wicker describes occurs more often than people realize. Unfortunately, however, journal conventions cause investigators to omit discussions of substantive theorizing aspects of their work. We hope that reading this article increases your understanding of substantive theorizing and our research as much as writing it increased our own.

Adaptation, Psychological↗
PubMed1988

Nocturnal penile tumescence is diminished in depressed men.

Although depressed individuals commonly report decreased libido, it was not known if such changes are accompanied by neurophysiological alterations. Preliminary studies suggest that some depressed men may manifest diminished nocturnal penile tumescence (NPT), an objective measure of erectile capacity. We report NPT findings in 34 male outpatients with major depression (SADS/RDC) and an age-matched group of 28 healthy controls. A 3-night electroencephalographic (EEG) sleep/NPT protocol was utilized, with penile rigidity (buckling force) determined on night 3. Analysis of night 2 data by MAN-COVA revealed significant effects for age, the covariate (F = 2.86, p = 0.002), and diagnosis (F = 2.32, p = 0.02). Depressed men had significantly diminished NPT time (F = 16.8, p less than 0.001), even when adjusted for sleep time (F = 13.4, p less than 0.001) or rapid eye movement (REM) time (F = 7.2, p less than 0.01). NPT time was reduced by greater than or equal to 1 SD below the control mean in 40% of depressives and was comparable to the level seen in 14 nondepressed patients with a clinical diagnosis of organic impotence. An intermediate proportion of depressed patients (38%) had maximum buckling forces less than or equal to 500 g, indicating diminished penile rigidity, when compared to controls (16%) and men with presumed organic impairment (93%) (p less than 0.001). Diminished NPT time and low buckling force were associated with a history of erectile dysfunction within the index depressive episode (p less than 0.001). These findings suggest that depression in men is associated with a potentially reversible decrease in erectile capacity, which may be associated with significant sexual dysfunction.

Adult↗
PubMed1988

Intraoperative hemostasis and wound healing in intestinal anastomoses using the ILA stapling device.

Intraoperative hemostasis and wound healing of 24 side-to-side intestinal anastomoses constructed with the ILA stapling device were studied in 12 dogs by comparing the ILA-32 and ILA-52 staple cartridges. Hemostasis was evaluated by intraoperative measurement of blood loss and bleeding time at the staple line. There was no statistically significant difference in mean blood loss (p greater than 0.05) or mean bleeding time (p greater than 0.10) between the two cartridges. Wound healing was studied using bursting strength measurements and silicone rubber casting of the microvasculature at the staple line. At 3 days, 1 week, and 2 weeks postoperatively, there was no significant difference between bursting strength values achieved with the two cartridges. Microscopic examination revealed that wound healing in the ILA-52 anastomoses lagged behind healing in the ILA-32 anastomoses at each postoperative time period studied. The silicone rubber casting study showed a paucity of microvasculature at the healing staple line with the ILA-52 cartridge as compared with the ILA-32 cartridge. Our findings suggest that the ILA-52 cartridge does not offer significantly improved intraoperative hemostasis over the ILA-32 cartridge and may affect the microvasculature at the staple line in a way that delays wound healing.

Anastomosis, Surgical↗
PubMed1988

Extensive breast calcification in renal failure.

Breast calcification is an important mammographic finding. The appearance and pattern of calcification may be quite specific, reflecting either benign or malignant disease. This article describes an unusual pattern of calcification seen in secondary hyperparathyroidism, which is necessary to recognize because of its benign nature.

Adult↗
PubMed1988

A monoclonal antibody for the specific diagnosis of plague.

A stable mouse-cell hybridoma was obtained that secretes an IgA monoclonal antibody reactive with the fraction 1 (F1) envelope antigen of Yersinia pestis. Titres of the antibody typically ranged from 1:32 768 to 1:65 536 in mouse ascitic fluids.The monoclonal antibody formed a line of precipitation when run against F1 antigen in Ouchterlony gel diffusion tests. In tests of 235 strains of Y. pestis, lines of identity occurred between the precipitates formed with a solution of purified F1 antigen and the F1 antigen produced by the plague strains. No precipitates formed for 65 strains that were incapable of elaborating F1 antigen. Specificity of the monoclonal antibody for strains of Y. pestis producing F1 was also indicated by negative results for 50 yersinia strains other than Y. pestis tested by an ELISA that used the antibody to capture antigen.Experiments to determine the shelf-life of the antibody were conducted over 3-4 years. When the monoclonal antibody was freeze-dried in vials, titre was retained for three years when the vials were stored at -70 degrees C but only for two months when they were stored at ambient temperatures. When the antibody was freeze-dried in wells of ELISA plates, sensitivity of the plates for capture of F1 antigen was preserved for four years when the plates were stored at -70 degrees C compared with two weeks for plates stored at room temperature. When a solution of the antibody was sealed in wells of ELISA plates and refrigerated at 4 degrees C, reactivity of the antibody and sensitivity of the plates were retained for a year.Alternatives for the application of this monoclonal antibody in ELISA and other plague diagnostic procedures are discussed.

Animals↗
PubMed1988

Electrically heated simulator for relative evaluation of alternative infant incubator environments.

A 10.9-cm diameter, copper ellipsoid was electrically heated to provide a simulation of sensible heat transfer from a newborn infant. The use of this simulator to determine mean radiant temperature and convective heat-transfer coefficient was demonstrated in three commercial incubators: the Isolette (Model C-86, Narco/Air Shields); the Armstrong Care-ette (Ohio Medical Products); and the I. C. (Ohmeda). The relative performance of these environmental therapeutic devices in shielding an infant against radiant heat loss was judged by the deviation of mean radiant temperature from incubator air temperature, which was varied from 32-36 degrees C. Whereas the I. C. incubator exhibited a radiant temperature always 0.5 degrees C less than air temperature, the Care-ette incubator showed radiant temperatures of 4.0-5.5 degrees C below air temperature, and the Isolette displayed radiant temperatures of 2.7-4.7 degrees C (inner wall removed) and 2.0-3.8 degrees C (inner wall inserted) below air temperature. The relative performance of the incubators in preventing convective heat loss was judged from the magnitude of the convective heat-transfer coefficient, hv. The I. C. incubator had an hv = 4.52 W/m2/degrees C; the Care-ette, 5.55 W/m2/degrees C; and the Isolette 7.19 W/m2/degrees C (inner wall removed) and 6.23 W/m2/degrees C (inner wall inserted). Although an ellipsoid simulator is not an anatomically correct substitute for an infant, it does provide a reliable and convenient comparison of steady-state heat transfer characteristics of alternative environmental devices.

Body Temperature Regulation↗
PubMed1987

Medical management of chronic middle-ear effusion. Results of a clinical trial of prednisone combined with sulfamethoxazole and trimethoprim.

Prednisone for seven days plus the combination drug sulfamethoxazole and trimethoprim for 30 days was assessed in treating chronic middle-ear effusion present for at least eight weeks. Pneumatic otoscopy, tympanometry, and audiology at entry into the study, and one week and one month after therapy, documented the status of the middle-ear effusion. Clearing in both ears or in one when only one was involved was called complete resolution; clearing in one of two affected ears was called partial resolution. In the initial open trial, 13 of 24 patients experienced partial or complete resolution one month after therapy. Subsequently, 28 patients were enrolled in a randomized, double-blind, placebo-controlled clinical trial in which patients whose effusion failed to clear were crossed over to the alternative regimen. In this trial, ten treated children (71%) experienced partial or complete resolution one month after therapy compared with three (21%) in the control group. Patients enrolled in both trials whose effusion cleared were followed up monthly for six months. Seven of 29 patients required referral for ventilation tubes.

Child↗
PubMed1987

Prevention of shigellosis by a Salmonella typhi-Shigella sonnei bivalent vaccine.

We genetically modified attenuated Salmonella typhi strain Ty21a to express the form I O polysaccharide antigen of Shigella sonnei. Three doses of this bivalent, live oral vaccine strain (1-8 X 10(9) organisms/dose) were given to young adults who, along with unvaccinated controls, were challenged one month later with pathogenic S. sonnei. The vaccinees had 40% protection against diarrhea and 56% against Hematest-positive diarrhea. Two of three vaccine lots provided higher levels of protection (53% against diarrhea and 71% against Hematest-positive diarrhea), but the third lot, prepared for a large-scale field trial, demonstrated no protective efficacy. Vaccinees had serum and local intestinal immune responses to S. sonnei lipopolysaccharide, and the presence of specific serum IgA or IgG antibody before challenge with pathogenic S. sonnei was correlated with protection from illness. Some lots of this bivalent vaccine strain provide significant protection against S. sonnei disease, but the problem of lot-to-lot variability must be overcome.

Adult↗