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Biomedical subjects

H Harris

Publications and source records attributed to H Harris.

At least 181 records · Page 10Linked to original sources
PubMed1980

Expression of alkaline phosphatase loci in mammalian tissues.

Alkaline phosphatases [orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1] have been examined in liver, bone, kidney, intestine, and placenta from nine mammalian species by quantitative inhibition and thermostability studies and compared with alkaline phosphatases in the corresponding human tissues. In humans, three kinds of alkaline phosphatase can be sharply differentiated by these methods, one occurring in liver, bone, and kidney, one in intestine, and one in placenta. They are evidently determined by separate gene loci. In the mammals only two sorts of alkaline phosphatase were found: one, which occurs in liver, bone, kidney, and also placenta, corresponds to the human liver/bone/kidney enzyme and the other corresponds to the human intestinal enzyme. The findings support our earlier proposal that the expression of a distinctive type of alkaline phosphatase in human placenta is the consequence of a late evolutionary event which occurred subsequent to the divergence of the evolutionary lineage leading to humans from the various lineages leading to other mammalian species. The concentrations of the inhibitors, phenylalanine, homoarginine, phenylalanylglycylglycine, and levamisole, required to give 50% inhibition, [I(50)], of the liver/bone/kidney/placental (nonhuman) alkaline phosphatases showed no significant variation among the species. However, the [I(50)] values for the intestinal enzyme varied among species to a much greater extent. This implies that in the liver/bone/kidney/placental (nonhuman) alkaline phosphatase the structures of the binding sites for these inhibitors have been highly conserved during mammalian evolution, but there has been much greater divergence of these structures in the evolution of intestinal alkaline phosphatases.

Alkaline Phosphatase↗
PubMed1980

Placental alkaline phosphatase in nonmalignant human cervix.

At least three loci determine human alkaline phosphatases [orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1]: one coding for the placental form of the enzyme; at least one coding for the intestinal forms; and at least one for the liver, bone, and kidney forms. It is generally believed that the locus determining the placental form is, in the normal individual, expressed only in placenta. However, ectopic or aberrant expression of this locus occurs in certain malignancies of other tissues and in cell lines, such as HeLa, derived from malignancies. We have examined by thermostability, inhibition, and immunologic studies the alkaline phosphatases in endocervix, cervical mucus, and endometrium from nonpregnant women with no evidence of malignancy. It was found that on the average about 18% of the alkaline phosphatase activity in endocervix and in cervical mucus is placental in type, the remainder being of the liver/bone/kidney type. The quantity of the placental enzyme is, however, low and amounts to only about 0.5% of the amount in normal term placenta. In endometrium all the alkaline phosphatase activity was of the liver/bone/kidney type. Thus the placental alkaline phosphatase locus is expressed in nonmalignant endocervix. The result is of some significance in connection with the widely held view that the expression of placental alkaline phosphatase in certain malignancies (including cervical malignancy) is due to derepression of a locus for a fetal enzyme protein normally repressed in adult tissues.

Adult↗
PubMed1980

Microtubule-organizing centres in mammalian cells in culture.

When microtubules in animal cells are dissociated and then allowed to recover, they re-grow from discrete points in the cytoplasm known as microtubule-organizing centres (MTOC). The microtubules may be dissociated by antimitotic drugs such as colcemid, vinblastine and griseofulvin, or by chilling the cells. Immunofluorescence studies show that the number of MTOC seen does not depend on the concentration of antimitotic drug used or the duration of exposure to the drug; the same results are obtained with vinblastine, griseofulvin and colcemid. However, after cold treatment, the proprotion of cells showing only a single MTOC is greater than that seen with the antimitotic drugs and may exceed 90%. Evidence is presented for the view that procedures involving the use of antimitotic drugs give artificially high values for the number of MTOC per cell.

Animals↗
PubMed1980

Microtubule-organizing centres in binucleate cells and homosynkaryons.

Immunofluorescence studies showed that most binucleate Vero cells formed by virus-induced fusion or by inhibition of cytokinesis had a single microtubule-organizing centre (MTOC) when examined during the reassembly of microtubules after chilling, but two or more organizing centres when examined after exposure to colcemid. These findings suggest that although binucleate cells initially contain more MTOC than mononucleate cells, the extra MTOC are normally aggregated, so that the number of MTOC in binucleate cells tends to be reduced very quickly to that in mononucleate cells.

Animals↗
PubMed1979

Origin of the alkaline phosphatases in amniotic fluid.

The nature and origins of amniotic fluid ALP activity were investigated early (14 to 22 weeks) and late (25 to 44 weeks) in pregnancy. The total enzyme activities for both stages were significantly different and considerable changes in the activities of individual enzyme components occurred. Early activity consists of intestinal (81%), bone/liver/kidney (15%), and placental (4%) ALP. In late fluids, the values are 5%, 69% and 27%, respectively. The intestinal enzyme is shown to be of fetal origin, presumably arising from the direct entry of desquamated intestinal mucosal cells into the amniotic fluid. The bone/liver/kidney enzyme is mostly of maternal serum origin early with an increased fetal contribution toward term. Early in pregnancy, the placental ALP activity is probably derived both directly from the placenta and from the placental activity in maternal serum. The latter source contributes more toward term.

Alkaline Phosphatase↗
PubMed1979

Association of beta-glucosidase with intact cells of Thermoactinomyces.

The location of the B-glucosidase activity in a whole culture broth of the thermophilic organism Thermoactinomyces has been studied. Little beta-glucosidase activity was found in the culture filtrate, while the culture solids contained the major part of the activity of the whole culture broth. The activity does not appear to be adsorbed to the culture solids; rather there is evidence that it is an intracellular soluble enzyme(s). The pH and temperature optima for a crude beta-glucosidase preparation were determined to be pH 6.5 and 50--55 degrees C. Enzyme activity studies indicate that the same enzyme(s) accounts for the beta-glucosidase and the cellobiase activities. The validity of using the filter paper activity of culture filtrates from Thermoactinomyces to predict the total saccharification of cellulosic materials to glucose is discussed.

Cellulose↗
PubMed1979

Some thoughts about genetics, differentiation, and malignancy.

This article deals with three related questions: (1) whether malignancy is determined by genetic or epigenetic mechanisms; (2) whether epigenetic mechanisms, as conventionally defined, actually exist; (3) what criteria are appropriate for defining dominance or recessiveness of the malignant state in cell fusion experiments.

Animals↗
PubMed1979

Lack of homology between dog and human placental alkaline phosphatases.

Alkaline phosphatases [ALPases; orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1] from dog and human placenta, liver, bone, kidney, and intestine were investigated by inhibition studies with L-homoarginine, L-phenylalanine, and L-phenylalanylglycyl-glycine; by thermostability studies; and by electrophoresis, both before and after treatment with neuraminidase. The inhibitions obtained for each inhibitor with dog placental ALPase closely match those obtained with dog and human liver, bone, and kidney ALPases, but are quite different from those obtained with human placental ALPase. Dog placental ALPase is thermolabile, as are dog and human liver, bone, and kidney ALPases, in marked contrast to human placental ALPase, which is very thermostable. Dog placental ALPase has the same electrophoretic mobility as dog liver, bone, and kidney ALPases after removal of sialic acid residues with neuraminidase. Desialated human placental ALPase differs electrophoretically from desialated human liver, bone, and kidney ALPases, which show the same mobilities. Dog and human intestinal ALPases are distinguished by these various criteria from the liver, bone, kidney, and placental ALPases of both species, but are similar to each other. These results suggest that the ALPase gene locus expressed in dog placenta is not homologous to that expressed in human placenta. Rather, it appears to be homologous to the ALPase locus expressed in dog and human liver and possibly also bone and kidney. Other incomplete data suggest that this may also be true for placental ALPase in other mammalian species. One possible explanation is that human placental ALPase, a relatively recent newcomer on the evolutionary scene, arose from a gene duplication that occurred subsequent to the evolutionary divergence of many other mammalian species.

Alkaline Phosphatase↗
PubMed1979

Human cell lines expressing intestinal alkaline phosphatase.

At least three loci determine human alkaline phosphatases [orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1]: one coding for the placental form of the enzyme, at least one coding for the intestinal forms, and at least one for the liver, bone, and kidney forms. The alkaline phosphatase in cell line D98/AH-2 has been characterized by inhibition, thermostability, and electrophoretic studies. It is intestinal in type and resembles the fetal intestinal form somewhat more closely than the adult intestinal form. Intestinal alkaline phosphatase was found in the related cell lines Detroit 98, D98/S, and D98/AH-R. No placental alkaline phosphatase could be detected in any of these cell lines. This series of cell lines are believed, on the basis of earlier investigations, to be HeLa in origin but other HeLa cell lines show placental alkaline phosphatase. Loss of expression of the placental alkaline phosphatase locus probably occurred prior to the separation of Detroit-98 from the lineage leading to other HeLa cell lines and this has persisted in the Detroit-98 derivatives D98/AH-2, D98/S, and D98/AH-R. Another possibility is that placental alkaline phosphatase expression only appeared in the HeLa lineage subsequent to the separation of Detroit-98.

Alkaline Phosphatase↗
PubMed1979

Iron status in a general practice and its relationship to morbidity.

1. An epidemiological study of iron status in general practice has been undertaken. An age-sex register was established and a 10% stratified random sample (194 males and 220 females) of the patients above the age of 15 years was studied. A full blood count, serum Fe concentration, transferrin saturation and serum ferritin concentration were measured and correlated with clinical features associated with Fe deficiency. 2. The geometric mean for serum ferritin for males was 77 micrograms/l (20-196 micrograms/l) and for females 37 micrograms/l (8--177 micrograms/l). A low serum ferritin (male less than 30 micrograms/l, female less than 20 micrograms/l) in the absence of anaemia was found in fifteen males and thirty-five females. In this group forty patients had clinical features which are aetiologically associated with Fe deficiency. The incidence of similar features in a control group of thirty-three patients was seven. 3. It is suggested that this is indirect evidence that serum ferritin concentration is the most sensitive monitor of Fe status enabling the detection of pre-anaemic Fe deficiency.

Adolescent↗
PubMed1979

The quality of verbal interaction in homes for old people.

Some 4,500 verbal exchanges among residents, and between staff and residents were recorded during structured observations in eight British purpose-built Homes for old people. These interactions were initially categorised as 'supportive/acceptive' or as 'other'. Subsequently, the 'other' data from four of the Homes was further classified as 'instrumental' and 'unclassifiable'. The participants in the exchanges were noted (resident or staff) as was the mental status assigned to residents ('confused' or 'rational'). The data suggest that interactions among residents are more likely to be supportive/acceptive than are those between staff and residents; that, similarly, interactions among rational residents are more likely to be supportive than those between rational and confused residents, or than those among confused residents. Interactions between rational and confused residents are more likely to be supportive than those among confused patients. Further, the data indicate that interactions between staff and rational residents, and between staff and confused residents do not differ in quality; predominantly, interactions between staff and residents are instrumental. These interpretations of the data are discussed in relation to the care of residents in institutional settings.

Aged↗
PubMed1979

Tumorigenicity of cells transformed by Simian virus 40 and of hybrids between such cells and normal diploid cells.

A number of newly isolated clonal cell lines derived from diploid mouse embryo cells transformed by SV40 were examined in vitro and in vivo. Although these lines showed the properties that define transformation in vitro, they were not tumorigenic for many passages after their initial isolation. Cells from tumours eventually produced by the SV40-transformed cells were fused with diploid mouse embryo cells. The hybrids formed were initially non-tumorigenic. This indicates that a normal diploid cell can suppress the malignant phenotype of a tumorigenic SV40-transformed cell. The hybrid cells did, however, express the SV40 T antigen and they nad a clearly transformed phenotype in vitro. It thus appears that neither the transformed phenotype nor the expression of the SV40 T antigen are enough to endow a cell with the ability to grow progressively in vivo. The relationship between the transformed phenotype and tumorigenicity was further studied by fusing malignant mouse melanoma cells with non-tumorigenic SV40-transformed cells. The hybrids expressed the transformed phenotype in vitro but unable to form tumours in vivo. The changes that occur in cells after transformation by SV40 do not apparently affect the ability of these cells to suppress the malignant phenotype of tumour cells.

Animals↗
PubMed1979

Some linguistic considerations related to the issue of female orgasm.

The purpose of this paper has been to identify a linguistic issue that continues to cloud our thinking about the subject of female orgasm. A specific technical revision has been recommended, i.e., that female orgasms be described as either coital or noncoital. It has been suggested that we help our female patients to become aware of this vocabulary and that we let them know that the clitoral/vaginal dichotomy is incorrect. Systematic adherence to the correct vocabulary is therapeutic. The linguistic implications concerning the issue of female orgasm have been examined as they relate to both theory and practice. It has been argued that linguistic usage pertaining to female sexuality generally is the product of a patriarchal value structure and, as such, reflects patriarchal prejudices about female sexuality. It has been suggested that the apparent inability of many women to achieve coital orgasms is related to centuries-old cultural attitudes and that linguistic usages, particularly dichotomies, tend to perpetuate the prejudices that underlie many cultural attitudes. Freud's view of the role of language in clinical practice has been indicated. Finally, it has been suggested that the linguistic recommendation made in this paper can be viewed as implementing the process by which recent biological findings are used to strengthen psychoanalytic theory and practice.

Female↗