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Biomedical subjects

S Williams

Publications and source records attributed to S Williams.

At least 523 records · Page 29Linked to original sources

Synovial fluid stimulates the proliferation of rabbit ligament. Fibroblasts in vitro.

This study was designed to test the hypothesis that synovial fluid may be inhibitory to cell proliferation. The effects of bovine synovial fluid (SF) and hyaluronic acid (HA) on the proliferation of normal rabbit medial collateral ligament (MCL), anterior cruciate ligament (ACL), and MCL scar cells were therefore investigated. Cell lines established from rabbit tissues were plated, incubated, and allowed to attach before treatment with varying concentrations of SF, HA, and a balanced salt solution (BSS). The BSS group was added as a control to observe the effects of media dilution alone on cell proliferation. Cell numbers from each group were quantified at 24, 48, 72, and 96 hours. Results showed that for all cell types, cell proliferation during the log phase of growth was significantly stimulated by SF. Maximum stimulation occurred in 20% SF with stimulation decreasing at higher concentrations of SF. HA had virtually no effect on scar and ACL cells, and only a slight stimulatory effect on MCL cells. Media dilution had no effect on scar cells and began to inhibit cell proliferation of ACL and MCL cells only at high dilutions. These findings suggest that low concentrations of bovine SF stimulate proliferation of rabbit ligament and scar fibroblasts in vitro by a mechanism that appears not to involve HA. Even in high concentrations, SF was not inhibitory to proliferation. The implications of these findings to ligament healing and normal ligament physiology require further investigation.

Animals↗

Hypertension in women: what is really known? The Women's Caucus, Working Group on Women's Health of the Society of General Internal Medicine.

PURPOSE: To determine whether there is sufficient information in the medical literature to guide appropriate treatment of hypertensive women. DATA IDENTIFICATION: Epidemiologic surveys of hypertension, clinical trials of antihypertensive therapy, and studies of selected adverse effects of antihypertensive agents were identified through a computerized search using MEDLINE and by identifying all studies cited in current medical textbooks as supporting evidence for the guidelines for the treatment of hypertensive individuals. All epidemiologic studies selected were cross-sectional or longitudinal, multicenter, population-based surveys. All clinical trials were large, randomized studies comparing one or more antihypertensive agents with a placebo or nonplacebo control group. Epidemiologic studies and clinical trials were reviewed to assess the quantity and quality of information available regarding important aspects of hypertension in women. Data pertaining to epidemiology, natural history, results of treatment, and two significant side effects of antihypertensive treatment were examined. RESULTS OF DATA ANALYSIS: The prevalence of hypertension is greater in black women than in black men and is about equal in white women and men. Because women outnumber men in the population, there are more hypertensive women than men. The attributable risk percent (the proportion of end points that could be eliminated by removing hypertension) for cardiovascular complications of hypertension is higher for women than men. Clinical trials show clear benefit of therapy for black women but no clear benefit for white women; some studies suggest that treatment of white women is harmful. Lipid profiles and their relation to ischemic heart disease differ for women and men; there is currently no information on the effects of antihypertensive agents on serum lipids in women. Few data have been published on the frequency of sexual dysfunction in treated hypertensive women. CONCLUSIONS: Hypertension in women and its related cardiovascular outcomes are a major public health problem. Clinical trials of antihypertensive therapy do not fully support current guidelines for the treatment of hypertensive women. Research concerning adverse effects of antihypertensive agents has largely excluded women from consideration; further studies are required to guide appropriate treatment.

Black or African American↗

Primary structure of alpha 2-macroglobulin receptor-associated protein. Human homologue of a Heymann nephritis antigen.

The alpha 2-macroglobulin (alpha 2M) receptor complex as purified by affinity chromatography contains three polypeptides: a 515-kDa heavy chain, an 85-kDa light chain, and a 39-kDa associated protein. Previous studies have established that the 515/85-kDa components are derived from a 600-kDa precursor whose complete sequence has been determined by cDNA cloning (Herz, J., Hamann, U., Rogne, S., Myklebost, O., Gassepohl, H., and Stanley, K. (1988) EMBO J. 7,4119-4127). We have now determined the primary structure of the human 39-kDa polypeptide, termed alpha 2M receptor-associated protein, by cDNA cloning. The deduced amino acid sequence contains a putative signal sequence that precedes the 323-residue mature protein. Comparative sequence analysis revealed that alpha 2M receptor-associated protein has 73% identity with a rat protein reported to be a pathogenic domain of Heymann nephritis antigen gp 330 and 77% identity to a mouse heparin-binding protein termed HBP-44. The high overall identity suggests that these molecules are interspecies homologues and indicates that the pathogenic domain, previously thought to be a portion of gp 330, is in fact a distinct protein. Further, the 120-residue carboxyl-terminal region of alpha 2M receptor-associated protein has 26% identity with a region of apolipoprotein E containing the low density lipoprotein receptor binding domain. Pulse-chase experiments revealed that the newly formed alpha 2M receptor-associated protein remains cell-associated, while surface labeling experiments followed by immunoprecipitation suggest that this protein is present on the cell surface forming a complex with the alpha 2M receptor heavy and light chains.

Amino Acid Sequence↗

Monoclonal antibody 323/A3: a marker for the presence of breast carcinoma.

The monoclonal antibody 323/A3 has been suggested as a marker of cancer risk in benign breast disease. Patients who have had both a benign biopsy and a later biopsy for breast carcinoma were studied. The staining patterns in the biopsies were analysed using a semi-quantitative recording system adapted from Mariani-Costantini et al. Immunohistochemical (IHC) staining was carried out on formalin fixed paraffin embedded tissue sections. In apocrine metaplasia the cytoplasm of benign tissue did not stain with 323/A3 whereas in the biopsies with associated breast cancer 5 of 7 biopsies stained, a statistically significant difference. A positive predictive value of 100% was noted for strong cytoplasmic staining to indicate the presence of carcinoma and this phenomenon may be useful as a means of demonstrating patients who have malignant breast disease in which a biopsy has inadequately sampled the breast tissue.

Adult↗

Oestrogen-regulated 24-kDa protein--a marker for breast carcinoma in benign breast tissue.

A monoclonal antibody (mAb) raised to an oestrogen-induced protein (24-kDa protein) has been suggested as a marker of women at risk of developing breast cancer. Patients with benign breast biopsies who have not developed breast cancer (benign control groups) were compared to women who had malignant breast biopsies. The benign tissue components from each group were studied. Subsequently, women with benign breast biopsies who have not developed malignancy were compared to women with benign breast biopsies who later went on to develop breast cancer. The study was carried out on formalin-fixed paraffin-embedded tissue sections. Comparison between tissue from the benign control groups and from women with breast cancer demonstrated the cytoplasmic staining in apocrine metaplasia of benign controls to be more pronounced. No staining differences were apparent between benign biopsies of patients who have not developed breast cancer and benign biopsies of those who have. We conclude that diminished expression in apocrine metaplasia of mAb to 24-kDa protein may indicate the presence of breast cancer but we have been unable to establish the role of 24-kDa protein as a marker for cancer risk.

Adult↗

Contralateral pneumonectomy after single-lung transplantation for emphysema.

An intractable contralateral air leak developed in a 46-year-old woman after right single-lung transplantation for emphysema. A left pneumonectomy was performed on postoperative day 17, leaving the patient with only one transplanted lung. Fifteen months postoperatively the patient is well and has satisfactory pulmonary function. Survival with a good quality of life is possible after single-lung transplantation and bilateral sequential pneumonectomies.

Female↗

Mucinous neoplasm in the cervix associated with a mucinous neoplasm in the ovary and concurrent bilateral sex cord tumors with annular tubules: immunohistochemical study.

The patient described synchronous mucinous tumors of the cervix and ovary and concurrent annular tubules, but without the classical stigmata of Peutz-Jeghers syndrome. The cervical tumor was an invasive mucinous adenocarcinoma with mixed components of minimal deviation and less-well-differentiated endometrioid morphology. The ovarian tumor had the benign appearance of a mucinous adenoma but histologically revealed areas of invasive carcinoma. Immunohistochemical studies of the mucinous neoplasms of the cervix and ovary are discussed. Neither the staining properties of mucin, the pattern of immunostaining for carcinoembryonic antigen, nor any other common markers were helpful in distinguishing the mucinous neoplasms. Positive immunostaining for low-molecular-weight cytokeratin in the filament profile of sex cord tumors with annular tubules was of particular interest since it has not to our knowledge been previously described.

Adenocarcinoma, Mucinous↗

Acridine orange staining reaction as an index of physiological activity in Escherichia coli.

The assumption that the acridine orange (AO) color reaction may be used as an index of physiological activity was investigated in laboratory grown Escherichia coli. Spectrofluorometric observations of purified nucleic acids, ribosomes and the microscopic color of bacteriophage-infected cells stained with AO confirmed the theory that single-stranded nucleic acids emit orange to red fluorescence while those that are double-stranded fluoresce green in vivo. Bacteria growing actively in a rich medium could be distinguished from cells in stationary phase by the AO reaction. Cells from log phase appeared red, whereas those in stationary phase were green. However, this differentiation was not seen when the bacteria were grown in a minimal medium or when a variation of the staining method was used. Also, shifting bacteria in stationary phase to starvation conditions rapidly changed their AO staining reaction. Boiling and exposure to lethal concentrations of azide and formalin resulted in stationary-phase cells that appeared red after staining but bacteria killed with chlorine remained green. These findings indicate that the AO staining reaction may be suggestive of physiological activity under defined conditions. However, variables in staining and fixation procedures as well as uncertainties associated with mixed bacterial populations in environmental samples may produce results that are not consistent with the classical interpretation of this reaction. The importance of validating the putative physiological implications of this staining reaction is stressed.

Acridine Orange↗

Social competence in adolescence: preliminary findings from a longitudinal study of New Zealand 15-year-olds.

Recently, there has been an increase of research interest in the nature of the relationship between the concept of "competence" and mental health and disorder. For a large sample of adolescents studied at ages 11 and 15 years, we developed indices of social competence at each age based on measures of social attachment and involvement in activities. There was a significant association between competence and "externalizing" disorders at both ages. Competence was related to "internalizing" disorder only at age 11. Preadolescent social competence did not predict later disorder at age 15 in the sample as a whole. However, externalizing disorder at age 15 was predicted by presence of disorder together with low social competence in preadolescence.

Achievement↗

A twelve-year follow-up of preschool hyperactive children.

Two percent (N = 21) of a large sample of preschool children were identified as "pervasively hyperactive." Compared with nonhyperactive preschoolers, these children more often came from families with high levels of adversity, and they showed poorer language skills. Over a 12-year follow-up period, the hyperactive preschoolers continued to show poorer cognitive skills, lower levels of reading ability, disruptive and inattentive behaviors at home and at school, and higher rates of DSM-III disorder in preadolescence and adolescence. By age 15, only one-quarter of this group were identified as having met "recovery" criteria. The findings point to the long-term adverse consequences of preschool hyperactivity and indicate the need for intervention with this type of disorder.

Adolescent↗