Search PubMed⌕ Search

Biomedical subjects

S Green

Publications and source records attributed to S Green.

At least 433 records · Page 24Linked to original sources
PubMed1981

A protein fraction (NHG) from serum of normal humans which is cytotoxic for HeLa cells in culture.

A fraction of the alpha-globulins (NHG) from normal human serum was cytotoxic for mouse L-cells in culture and Meth A tumors in mice. NHG inhibited the growth in vitro of human colon cancer (HT-29), melanoma (RPMI 7931) and a neuroblastoma cell line. Survival of HeLa S-3 cell colonies after 24 h exposure to 25, 50, 75 or 100 micrograms NHG/ml medium was 86%, 77%, 40% and 10%, respectively. Whole human serum or purified serum albumin had no anti-HeLa cell activity. These results confirm the presence of a protein in human serum with antitumor activity. An assay for NHG using HeLa S-3 tumor cells is described.

Alpha-Globulins↗
PubMed1981

Screening for disability in the inner city.

A 10% sample of private households on the electoral register of the London borough of Lambeth was screened for disable persons aged 16 and over, using a postal questionnaire. After three mailings and individual follow-up of non-responders, 87% of the sample households returned questionnaires. Disability was defined in the screening questionnaire as functional limitations or activity restrictions consequent upon disease or impairment. The overall point prevalence of disability was estimated at 15.4% and the most frequently reported impairments were those of the sense organs, bones, central nervous, circulatory, and respiratory systems. Hearing difficulties were the single most frequently reported functional limitation. A log-linear modelling procedure identified age, marital status, and working status as the factors most strongly associated with disability for both men and women. In addition, men aged 50-64 and not working, and men in manual occupations and living alone, were more likely to report disability. These findings indicate that some population groups are disable by functional limitations and activity restrictions not included in office criteria of identification and assessment. These criteria might be broadened, and serves planned for those population groups with higher rates of reported disability.

Adolescent↗
PubMed1980

Two modes of phosphate transport by turtle urinary bladder.

The effects of changes in pH and addition of CO2/HCO3- on transepithelial phosphate transport were studied in turtle urinary bladder. Net mucosa-to-serosa flux of phosphate (JP) was determined as the difference between unidirectional 32P fluxes in the absence of transepithelial electrochemical gradients. With 5 mM phosphate in HCO3--free Ringer at pH 8.4, JP was 21.8 +/- 7.4 nmol . 8 cm-2 . h-1. There was a slight increase in JP with isohydric addition of 10 mM HCO3-. Addition of 5% CO2, which reduced pH to 7.3, did not affect JP. At pH 8.4, JP was not affected by ouabain or dinitrophenol and increased progressively as phosphate concentration was raised between 0.5 and 10 mM. At pH 6.2 in the absence of exogenous CO2 and HCO3-, JP was undectable. With 2.5 mM HCO3- and 5% CO2 at pH 6.5, JP was 61.3 +/- 16.0 and decreased to 30.6 +/- 1.6 nmol . 8 cm-2 . h-1 when pH was raised to 7.2 by increasing HCO3- to 10 mM. At pH 6.5 JP was inhibited by both ouabain and dinitrophenol. These results suggest that at acidic pH, JP results from the tranport of H2PO4-. The transport of H2PO4- is CO2 dependent and inhibited by ouabain and dinitrophenol. In contrast, at alkaline pH, JP results from the transport of HPO4(2-), which is neither CO2 dependent nor inhibited by ouabain or dinitrophenol.

Animals↗
PubMed1980

Evaluation of a postal screening questionnaire to identify the physically disabled.

In this study a postal screening questionnaire was compared with an interviewer-administered questionnaire for identifying disabled persons living in the community. Disability was defined as difficulty with specified activities of daily living, specified medical problems which often cause disablement, and frequent use of a formal health or social service. A 91 per cent response rate to the screening questionnaire was obtained from a random sample of 793 adults in a general practice; 89 were classified as "disabled". Seventy-eight per cent of those subsequently interviewed changed their response to at least one item; this figure fell to 29 per cent when frequent use of formal services was excluded from the definition of disability. None of the persons classified as disabled from the postal survey were considered to be non-disabled after interview. Interviews with a sample of persons who did not report disability on the postal questionnaire resulted in no changes in classification. General practitioners (GPs) who completed screening questionnaires on respondents with the help of practice records were aware of only 79 of 206 disability items reported. The GPs were more aware of respondents' difficulties with activities of daily living than of their medical problems.

Disability Evaluation↗
PubMed1979

The surviving twin.

Explore the source record for details and available documents.

Diseases in Twins↗
PubMed1979

Species-specific perceptual processing of vocal sounds by monkeys.

Monkeys of four species were trained to discriminate between sets of natural tonal calls of Japanese macaques (Macaca fuscata) by the position of a frequency-inflection peak or by initial pitch. The Japanese macaques consistently performed best on peak position and the other species on pitch. The results imply special strategies for perceptional processing of vocal sounds and suggest parallels with human speech perception.

Animals↗
PubMed1979

Complement fixation for study of placental-type alkaline phosphatase.

Preparations of human placental alkaline phosphatase differing in specific enzyme activities were compared by microcomplement fixation assays using monospecific antisera. While both specific enzyme activity and complement fixation units increased 15,000-fold upon purification, the ratio between these units remained constant. Separation of an alkaline phosphatase preparation into 'A' and 'B' forms by ampholine isoelectric focusing indicated that these forms also possessed the same ratio of immunoreactive enzyme protein to enzyme activity. The correspondence of complement fixation units with specific enzyme activity indicates that complement fixation with monospecific antisera can be used to analyze structural differences among alkaline phosphatase isoenzymes.

Alkaline Phosphatase↗
PubMed1979

Dominant lethal assay of some hair-dye components in random-bred male rats.

Male rats were exposed to maximally tolerated doses of 5 hair-dye components in a dominant lethal test. Each component was tested at 3 dosage levels with 15 random-bred male rats per level. The highest dose, selected on the basis of subacute toxicity testing, generally reduced weight gains without being lethal. Freshly prepared solutions were injected i.p. at 1 ml/kg 3 times a week for 10 weeks. Rats injected with dimethylsulfoxide and triethylenemelamine served as solvent and positive controls, respectively. A majority of rats survived the treatment at the levels tested and were mated to two virgin females each per week for 2 weeks. The females were sacrificed at midterm of pregnancy and examined for live and dead implants. Dominant lethality was evaluated on the basis of 4 criteria: dead implants per pregnant female, dead implants per total implants, proportion of females with one or more dead implants, and proportion of females with two or more dead implants. 2-Nitro-p-phenylenediamine, 2,4-diaminoanisole sulfate and 2,5-diaminoanisole sulfate produced negative responses, whereas m-phenylenediamine and 4-nitro-o-phenylenediamine induced weak dominant lethality in the first trial. On retesting these weakly positive components, both m-phenylenediamine and 4-nitro-o-phenylenediamine produced negative responses.

Animals↗
PubMed1979

Evidence for the presence of an antitumor factor in serum of normal animals.

We have previously reported finding a factor with antitumor activity (TNF, tumor necrosis factor) in extracts of serum from normal mice. The possibility that TNF exists in the blood of normal animals of other species was explored. Horse, mouse, dog, human, sheep, calf, rat and shark serums were fractionated with (NH4)2SO4 and filtered through S-200 sephacryl gel. Proteins of molecular weight 90,000 to 180,000 were pooled, concentrated and dialyzed. TNF, determined by L-cell assay in vitro and Meth A assay in vivo found in fractions from mouse, dog and human serum. Agarose electrophoresis of the TNF from mouse and human serum indicated the principle components were alpha 1-alpha 2 globulins. Preparative PAGE indicated that mouse TNF migrated slowly and was made up of at least 4 components while human TNF was a faster moving, monomeric protein.

Alpha-Globulins↗
PubMed1979

Assessing functional status among elderly patients: a comparison of questionnaire and service provider ratings.

This paper describes a comparative analysis of questionnaire-based measures of functional status and clinical ratings of disability made by general practitioners and health visitors. Both approaches to functional assessment were used in rating 92 elderly primary care patients in terms of their performance of 13 mobility and self-help activities. Simple dichotomous and more complex trichotomous measures of performance were used to summarize functional ability in both the questionnaire and the provider's evaluation. Agreement between questionnaire-based and rater assessments was greatest for less complex mobility and self-help functions in comparisons using both dichotomous and trichotomous scales.

Activities of Daily Living↗
PubMed1979

Monkey vocalizations and human speech: parallels in perception?

Primate vocal repertoires may be classified along a continuum of discrete vs. graded signals, with the placement of a particular repertoire a result of the interplay between the species' social organization and adaptive specializations of individual signals engendered by the physical environment and their use. Discussion of the different types of graded signals reveals that they may possess either transitional, ontogenetic, or internal variability. Upon examination, the speech of humans is found to contain primarily internally graded signals, and it is suggested that the major phenomena of human speech perception are related to this internally graded quality. Based on this analysis of human speech, it is proposed that other species possessing internal gradings (e.g., Japanese macaques) are also likely to demonstrate similar perceptual phenomena for their own graded vocalizations.

Animals↗
PubMed1979

Effects of murine tumor necrosis factor on heterotransplanted human tumors.

A partially purified glycoprotein fraction (the G-200 II fraction) obtained from sera of CD-1 mice sensitized with Corynebacterium parvum and treated with endotoxin was designated as tumor necrosis factor (TNF). Human melanoma cells exposed to this factor in vitro had decreased tumorigenicity when injected into nude mice. Human melanoma, embryonal adenocarcinoma of the testis and colon carcinoma heterotransplanted in nude mice exhibited regressions in size following intraperitoneal injections of TNF. The responses were related to dose and duration of exposure.

Adenocarcinoma↗