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Biomedical subjects

J Levin

Publications and source records attributed to J Levin.

At least 379 records · Page 21Linked to original sources
PubMedDate not supplied

Thyroxine binding globulin and thyroid function tests in patients with hepatocellular carcinoma.

To determine the prevalence of elevated serum concentrations of thyroxine binding globulin (TBG) in patients with hepatocellular carcinoma (HCC) and the influence of the associated cirrhosis, TBG was measured in 39 patients with HCC, 22 with and 17 without cirrhosis, in 20 patients with cryptogenic macronodular cirrhosis but without HCC, and in 40 matched controls. The mean serum TBG concentration in the patients was 34.5 +/- 17.7 microgram per ml, compared to 21.4 +/- 6.8 microgram pr ml in controls and 20.5 +/- 6.3 microgram per ml in cirrhosis without HCC (p less than 0.01). The presence or absence of cirrhosis in the HCC patients did not significantly influence the frequency with which elevated TBG levels were found; levels were normal in every subject with cirrhosis and no HCC. The mean thyroxine (T4): TBG ratio was 5.58 +/- 1.78 in controls and was reduced in HCC patients with both elevated (3.33 +/- 0.80, p less than 0.001) and normal TBG values (4.39 +/- 1.90, p less than 0.05), and in cirrhotics without HCC (4.29 +/- 1.01, p less than 0.01). T4 and TBG concentrations correlated significantly in controls, in HCC patients with elevated TBG, and in the cirrhotics without HCC. It is concluded that in patients with HCC (i) TBG levels may be elevated both in the presence or absence of cirrhosis; (ii) there is reduced binding of T4 TBG, and (iii) a low T4:TBG ratio excludes the diagnosis of hyperthyroidism in the presence of high T4 levels. TBG levels are normal in patients with cryptogenic macronodular cirrhosis without HCC.

Adult↗
PubMedDate not supplied

Amplification of chromogenic staining of proteases within electrophoretic gels.

A method is described for amplification of bands generated by chromogenic substrates following their reaction with proteases within electrophoretic gels. Chromogenic substrates, consisting of synthetic peptides containing the chromophore 4-nitroaniline (paranitroaniline, PNA), are applied directly to the surface of agarose or acrylamide gels. Protease activity within the gel results in the enzymatic amidolysis of the chromogenic substrates, releasing free PNA. The yellow PNA chromogen is then derivatized by reaction with p-dimethylaminocinnamaldehyde (DACA) to form a purple Schiff base compound. The resultant complex has a significantly higher molar absorbancy than the original PNA chromogen, thus increasing the sensitivity for low levels of amidolytic activity. The derivatized chromogen is easily visualized for photography.

Aniline Compounds↗
PubMedDate not supplied

Psychophysiological reactivity to alcohol advertising in light and moderate social drinkers.

Psychophysiological responses to alcohol and nonalcohol advertising slides were compared in light and moderate social drinkers. Each slide presentation was interspersed with a rest period. Before viewing the slides, participants completed a questionnaire to estimate their quantity and frequency of alcohol consumption. Participants were divided into two groups using a median split of alcohol consumption scores. Light social drinkers showed a significant decrease in heart rate response to both alcohol-related and nonalcohol advertisements. Moderate social drinkers showed a significant increase in skin conductance to both alcohol-related and nonalcohol advertisements. The findings of this study have implications for understanding both the influence of alcohol advertisements on behavior and the psychophysiological correlates of cue reactivity.

Adult↗
PubMedDate not supplied

Production of modified crosslinked cell-free hemoglobin for human use: the role of quantitative determination of endotoxin contamination.

In vivo toxicity remains a major barrier to the successful use of cell-free hemoglobin (Hb) as an oxygen carrier in humans. Bacterial endotoxin (lipopolysaccharide, LPS) is known to contribute to the in vivo toxicity of Hb preparations, and the prevention of LPS contamination is a critical aspect of the effort to create an efficacious Hb blood substitute. Limulus amebocyte lysate assays for endotoxin were performed on multiple Hb samples from 26 independent production runs for the preparation of human crosslinked cell-free hemoglobin (alpha alpha Hb). High levels of LPS contamination (1- > 100 ng/mL) of alpha alpha Hb solutions were detected in multiple samples during many of the initial production runs. It was observed that LPS contamination of alpha alpha Hb solutions could occur at any step during the production sequence. Substantial enhancement by alpha alpha Hb of the biologic effects of LPS was demonstrated by two independent assays for endotoxin (the Limulus amebocyte lysate test and a mononuclear cell procoagulant assay), whereas LPS biologic activity was only slightly increased by human serum albumin and substantially diminished by IgG. These results suggest that the prevention of LPS-related toxicities in vivo may be more important to the clinical use of Hb solutions than to the use of other intravenous protein products. Therefore, it was encouraging to note that, with the careful monitoring for LPS in the production facility and in multiple samples during cell-free Hb production, sources of LPS contamination were recognized and the appropriate sites were made endotoxin-free.(ABSTRACT TRUNCATED AT 250 WORDS)

Cells, Cultured↗
PubMedDate not supplied

The medial acetabular wall: normal measurements in different population groups.

Measurements of the acetabulum and particularly the medial acetabular wall were done on 90 skeletons. Mean and standard deviations for different population groups are presented. The purpose of this study was to establish the normal range of values for the thickness of the medial wall of the acetabulum. This information is of value for the radiologist and the orthopaedic surgeon in the pre- and intraoperative assessment of the bone reserve of the acetabular fossa in hip surgery.

Acetabulum↗
PubMedDate not supplied

A role for platelet release of serotonin in the initiation of contact sensitivity.

Finding contact sensitivity (CS) responses that were fairly normal in ear swelling, and in serotonin (5-HT) dependence in mast-cell-deficient mice, led to experiments to determine whether platelets supplemented mast cells as a source of 5-HT in CS. Severe depletion of platelets, and consequently blood 5-HT, with antiplatelet antibody, strongly inhibited CS, especially in mast-cell-deficient mice, suggesting that platelets supplemented mast cells. Furthermore, human platelets sensitized in vitro with anti-(tri-nitro-phenyl) IgE, and transferred intravenously together with isolated late-acting effector T cells, provided CS initiation due to local 5-HT release. Similar, IgE-dependent in vitro release of 5-HT was C dependent. These findings establish the importance of antigen-specific platelet release of 5-HT in CS initiation.

Amphetamine↗
PubMedDate not supplied

Abnormal hormone levels in men with coronary artery disease.

Plasma concentrations and urinary excretions of various hormones and hormone metabolites were measured in four groups. Group 1 was composed of 13 men with prior myocardial infarction; Group 2 contained 35 clinically normal men; Group 3 consisted of 44 men with normal coronary arteriograms; and Group 4 was composed of 25 men with severe coronary artery disease shown on arteriogram but no infarction. There were four major findings: Group 1 had significantly higher 24-hour mean plasma concentrations of estrone (E1), dehydroisoandrosterone (DHA), and dehydroisoandrosterone sulfate (DHAS) than Group 2, while Group 3 had the same levels as Group 4; Group 4 had significantly lower urinary excretion of androsterone glucuronide (AG) than Group 3, while Group 1 excreted normal amounts. There are three possible explanations for these findings: 1) myocardial infarction occurring in men with coronary artery disease may elevate the plasma levels of E1, DHA, and DHAS and eliminate the preinfarction depression of urinary AG levels; 2) higher than average levels of E1, DHA, DHAS, and AG may favor the development of infarction in men with coronary artery disease; 3) higher than average levels of E1, DHA, DHAS, and AG may favor survival from any infarction that occurs in men with coronary artery disease. Experimental and epidemiological evidence seems to favor the third possibility.

Adult↗
PubMedDate not supplied

The elderly sick role: an experimental analysis.

This experiment sought to determine whether young people ascribe different sick-role expectations to the elderly than to the middle-aged. The study also examined whether such expectations are a function of age per se or of work status. The experiment was a two X two factorial design employing two levels of age and two levels of work status. Sick-role expectations were elicited by the use of vignettes in which illness characteristics and background information were identical, but age and work status were varied. Results partially support the contention that the young ascribe an elderly sick role. Respondents were more likely to expect an old, rather than a middle-aged man, not to recover. However, respondents were also more likely to expect reduction in role obligations when the man was retired than when he was employed, regardless of age.

Adult↗
PubMedDate not supplied

Scoliosis in pediatric spinal cord-injured patients.

One hundred thirty children who sustained spinal cord injuries between birth and age 21 years were reviewed to determine the progression rate of paralytic scoliosis and the effects of bracing and surgery. Patients were divided into two groups: those injured before and those injured after the adolescent growth spurt. Scoliosis developed in 97 and 52%, respectively. Bracing was effective in delaying progression in the preadolescent group. The progressive paralytic spinal deformity did not appear to be related to the level of injury. The older patient is at much less risk for paralytic scoliosis, but still requires routine examination.

Adolescent↗
PubMedDate not supplied

Nonobesity at the time of mastectomy is highly predictive of 10-year disease-free survival in women with breast cancer.

25 unselected women with operable breast cancer were followed after radical mastectomy until they died of recurrent cancer (non-survivors), or for 10 years if there was no recurrence (survivors): all the women still alive at 10 years were clinically and radiographically disease-free. Survivors and non-survivors were compared with respect to premastectomy height, and deviation from ideal weight. There were 16 women in the survivor group; at the time of mastectomy, they averaged 11% above ideal weight and only 4 of them (25%) were obese (20% or more above ideal weight). There were 9 women in the non-survival group; they averaged 51% above ideal weight at the time of mastectomy and all of them were obese, as defined. The intergroup difference in mean deviation from ideal weight was very highly significant (P less than 0.0001). Of the 13 women who were obese at mastectomy, only 4 (31%) became survivors, while 100% of the 12 women who were non-obese at mastectomy became survivors; the difference in percent survival was very highly significant (P less than 0.005). Separate evaluation of the roles of height and weight showed that height was not a factor and weight accounted entirely for the observed differences. It appears that maintenance of nonobesity may be a more effective way of decreasing mortality from breast cancer than any other measure proposed to date.

Adult↗