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Biomedical subjects

I Robbins

Publications and source records attributed to I Robbins.

30 records · Page 2Linked to original sources
PubMed1992

The occurrence and in vitro effects of molecules potentially active in the control of growth in the marine mussel Mytilus edulis L.

A molecular with a molecular weight, estimated by gel filtration, of approximately 22 kDa and immunoreactive to anti-human hypophysial growth hormone (hGH) has been identified by radioimmunoassay in the digestive gland and hemolymph of the mussel Mytilus edulis L. The dilution curve of this molecule was parallel to that of hGH, suggesting that the antigenic site of the Mytilus molecule is similar to that of hGH. Immunoreactive fractions resulting from gel filtration failed to stimulate protein synthesis in dispersed mantle-edge cells in vitro. No hGH-immunoreactive material was detected in the cerebral ganglia. It is thus clear that a small protein-synthesis-stimulating factor (PSSF), identified in the cerebral ganglia and hemolymph by its action in vitro on dispersed mantle-edge cells, is not analogous to the Mytilus hGH-immunoreactive molecule. Likewise, a somatostatin-immunoreactive molecule present in the hemolymph of Mytilus did not coelute with PSSF. Evidence is presented that PSSF is a hydrophilic peptide that stimulates DNA, RNA, and protein synthesis and that is not tissue specific. These characteristics suggest that PSSF is a growth hormone.

Animals↗
PubMed1992

The relationship between knowledge, attitudes and degree of contact with AIDS and HIV.

This study examined the relationship between knowledge, attitudes, and degree of contact with AIDS and HIV for three groups of people: nurses, psychology students and design students using a standardized questionnaire. The questionnaire differentiated between the groups on all three dimensions with nurses having most knowledge but least positive attitudes. There was no relationship between knowledge and attitudes for the three groups although contact and knowledge were related for the design students and attitudes and contact were related for the psychology students. For all groups the strongest relationship was between attitudes and contact. The implications of the results for training courses are discussed.

Adolescent↗
PubMed1992

Staff anxieties about death in residential settings for elderly people.

This study examined the relationship between death anxiety, the anxiety surrounding dealing practically with dying, and the level of experience of care assistants in residential settings for the elderly. It also examined the perception of the officer in charge of the establishment of the care assistants' level of anxiety. Age was the best predictor of both death anxiety and practical anxiety, the two being correlated. There was also a difference in perception of staff anxiety as a consequence of ethnic-group membership. The implications of this for training and practice are discussed.

Adult↗
PubMed1991

Mechanisms involved in parasitic castration: in vitro effects of the trematode Prosorhynchus squamatus on the gametogenesis and the nutrient storage metabolism of the marine bivalve mollusc Mytilus edulis.

The mechanisms involved in the parasitic castration of the marine mussel Mytilus edulis by the trematode parasite Prosorhynchus squamatus Odhner, 1905, have been investigated in vitro with two bioassays employing dissociated host tissues. There is no conclusive evidence that P. squamatus affects the secretion of two host neuroendocrine factors, viz., gonial mitosis-stimulating factor and glycogen mobilization hormone, involved in the gametogenesis/nutrient storage cycles of the mussel. In contrast, extracts of P. squamatus sporocysts and cercariae significantly stimulated glycogen mobilization in host glycogen cells and strongly inhibited host gonial mitosis. A gonial mitosis-inhibiting factor (GMIF) was found in the hemolymph of parasitized mussels. The existence of an endogenous GMIF in mantle tissue of uninfected mussels has been demonstrated. This factor appeared to be secreted into the hemolymph during the period of sexual maturity. Whether the parasite acts directly on the host gonia, or by provoking the liberation of this endogenous GMIF, has yet to be ascertained. It would appear, however, that the parasite acts directly on host glycogen cells.

Animals↗
PubMed1991

Neuroendocrine factors affecting the glycogen metabolism of purified Mytilus edulis glycogen cells: partial characterization of the putative glycogen mobilization hormone--demonstration of a factor that stimulates glycogen synthesis.

A putative glycogen mobilizing hormone (GMH) from the marine mussel Mytilus edulis L. has been partially characterized. GMH activity is present in the cerebral ganglia and the hemolymph serum and promotes the mobilization of glycogen in isolated glycogen cells. The cerebral GMH is trypsin sensitive and partially heat labile and has an apparent molecular mass of greater than 20 kDa. Following fractionation of cerebral extracts by molecular mass, a second factor, with a molecular mass of ca. 1.5 kDa, was discovered. This factor stimulates post-incubation incorporation of 14C into glycogen in isolated glycogen cells.

Animals↗
PubMed1991

Models of nursing: their relevance to the care of elderly people.

The adoption of nursing models has become widespread throughout the profession with little empirical evidence of their usefulness or critical evaluation. This paper gives an overview of the issues surrounding the development and use of models and presents research data which indicates that one model (Roper, Logan & Tierney's Activities of Living) is problematic in the long-term care of the elderly. The characteristics of this model which are problematic are common to other models and have relevance for other areas of nursing.

Activities of Daily Living↗
PubMed1990

A putative neuroendocrine factor that stimulates glycogen mobilization in isolated glycogen cells from the marine mussel Mytilus edulis.

Glycogen synthesized by purified glycogen cells, from the labial palps of Mytilus edulis, was labeled by preincubation in culture medium containing D-[U-14C]glucose. It was stable for at least 4 hr of postincubation in the absence of 14C. Glycogen mobilization was provoked by an acid extract of the cerebral ganglia. The active factor was also found in the hemolymph. The glycogen cells exhibited a dose-dependent response to the cerebral extract. The active cerebral factor is methanol soluble and possesses hydrophobic properties. It is postulated that this factor is a neurohormone.

Animals↗
PubMed1988

A gonial mitosis-stimulating factor in cerebral ganglia and hemolymph of the marine mussel Mytilus edulis L.

A gonial mitosis-stimulating factor produced by the cerebral ganglia of the mussel Mytilus edulis has been demonstrated. This factor induces an increase of [3H]thymidine incorporation in the DNA of isolated mantle cells. Dose-response data are obtained with the methanol phase of an acidic ganglia extract. The rate of [3H]thymidine incorporation is compared with aspartate transcarbamylase specific activity, another bioassay previously described to estimate mitotic activity. This heat-stable mitogenic factor appears to have a molecular weight of less than 5000 Da. A gonial mitogenic factor is also found in the hemolymph and circulatory cells.

Animals↗
PubMedDate not supplied

Selective mRNA degradation by antisense oligonucleotide-2,5A chimeras: involvement of RNase H and RNase L.

Antisense oligonucleotides (ON) allow the specific control of gene expression and phosphorothioate derivatives are currently being evaluated for possible clinical applications. Numerous second generation ON analogues with improved pharmacological properties have been described. Most of them, however, do not recruit RNase H, which is known to increase ON potency by eliciting the specific degradation of the target RNA. Silverman, Torrence and colleagues have conjugated 2,5A to natural antisense ON and demonstrated the preferential cleavage of a target RNA in cell-free and intact cell experiments. We have established for the first time that RNase H-incompetent ON, viz. alpha-anomeric ON analogues, can be converted into sequence-specific nucleases upon conjugation to 2,5A. The use of alpha-ON- and beta-ON-2,5A chimeras has allowed us to delineate the part played by RNase H and RNase L in target RNA degradation and translation arrest. Finally, the present studies have revealed limitations which are encountered in the choice of a suitable target for such ON-2,5A chimeras.

Animals↗
PubMedDate not supplied

Research rituals.

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Ceremonial Behavior↗