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Biomedical subjects

S Martin

Publications and source records attributed to S Martin.

At least 523 records · Page 29Linked to original sources
PubMed1990

Role of coexpression of IL-2 and herpes simplex virus proteins in recombinant vaccinia virus vectors on levels of induced immunity.

Vaccinia virus recombinants co-expressing the genes for IL-2 and HSV-1 gC or gD were used to study the potential adjuvant effects of IL-2 on immunity to HSV-1. In addition, constructs were produced which, while expressing IL-2, encoded for reduced levels of HSV-1 gC. Studies with mice revealed that gC and gD could stimulate HSV-1 immunity as measured by neutralizing antibody (NA), lymphoproliferation and viral clearance. IL-2 enhancement of NA and lymphoproliferation was observed only in those groups of mice immunized with the sub-optimal gC construct which co-expressed IL-2. In no instance did the presence of IL-2 augment the ability of mice to clear an epithelial challenge of HSV-1.

Animals↗
PubMed1990

Characterization of a primate model of hypertension. The response of hypertensive and normotensive male vervets (Cercopithecus aethiops) to cold pressor stress, captopril administration, and acute bolus of atrial natriuretic factor.

In feral populations of African green monkeys or vervets (Cercopithecus aethiops), between 5 and 15% of adults have spontaneously elevated blood pressure (BP). We report here the initial biological and pharmacological characterization of this potential animal model of hypertension. Captive male monkeys with elevated systolic pressures show a modest pressure increase in response to stressors such as capture, phlebotomy and cold challenge. Acute captopril administration lowers BP in monkeys with high blood pressure (HBP), but has no effect on BP in control animals. Furosemide does not acutely reduce BP. Animals with elevated BPs have lower levels of angiotensin II than do age- and weight-matched controls. An acute infusion of atrial natriuretic factor (ANF) diminishes BP and stimulates urinary output in control and HBP vervets. However, both effects are more pronounced in animals with HBP. Heart rate is not affected by any of the experimental manipulations. Taken together, these data suggest that African green monkeys with spontaneously elevated BP may be a useful experimental model for particular types of human hypertension. Additional studies are required to complete the endocrine and pharmacological characterization of individual animals with HBP.

Analysis of Variance↗
PubMed1990

Murine cytotoxic T lymphocytes specific for herpes simplex virus type 1 recognize the immediate early protein ICP4 but not ICP0.

Vaccinia virus recombinants expressing the herpes simplex virus type 1 (HSV-1) genes encoding ICP0 or ICP4 were used to identify the precise target antigen(s) of murine anti-viral cytotoxic T lymphocytes (CTL) specific for the non-structural immediate early proteins. These studies revealed that HSV-1-specific CTL, restricted to class I major histocompatibility complex genes of the H-2k haplotype but not the H-2d or H-2b haplotypes, would lyse autologous cells expressing ICP4. HSV-1-specific CTL derived from various mice strains failed to lyse target cells expressing ICP0. Calculation of the frequencies of H-2k-restricted virus-specific CTL demonstrated that approximately a third of the total HSV-1-specific response was directed against ICP4. Immunization of mice with either recombinant vaccinia virus or transfected L cells expressing ICP4 induced HSV-1-specific lymphoproliferation and delayed hypersensitivity but CTLs were not induced. More importantly, such immunized animals were unable to resist or control a subsequent challenge with virulent HSV-1.

Animals↗
PubMed1990

Type of childcare at 18 months--I. Differences in interactional experience.

A longitudinal study has followed two-parent families and their first-born child. The families were chosen so that there were three groups of dual-earner families using relatives, childminders and nurseries for day care and one group of single-earner families. At 18 mths of age children in the study were observed in the four types of childcare setting. The data from the detailed observations were used to compare the children's interactional experience. The results indicate marked variation in the quality of children's experiences between different childcare settings. Possible reasons for such variation are discussed.

Attention↗
PubMed1990

Type of childcare at 18 months--II. Relations with cognitive and language development.

In a longitudinal study of women and their first-born children the relationship between type of day care experience and cognitive and language development at 18 mths of age was considered. There was a strong association between socio-economic characteristics and type of day care and analyses allowed for this. The results for cognitive development indicate a relationship with mother's education but not with type of day care. For language development the results indicate that children who experience group care were less likely to show much production of different word combinations, but that this was related to the children's language environments.

Child Care↗
PubMed1990

Organization, design, and implementation of an interventional cardiology patient care unit.

We have described the major steps required to open a new ICPCU. The unit allows for a comprehensive standardized approach to the education of patients undergoing interventional cardiology procedures and offers the optimal setting for nursing research in the field of interventional cardiology and cardiovascular nursing. Primarily, the advent of this unit has supported the implementation of primary nursing, allowed for optimal continuity of patient care, and contributed to a decrease in the length of hospital stay of these patients and an increase in patient and family satisfaction.

Angioplasty, Balloon, Coronary↗
PubMed1989

A lateral cap model of microtubule dynamic instability.

The co-existence and interconversion of growing and shrinking microtubules have been termed 'dynamic instability,' and have been directly observed to occur under a variety of conditions in vitro and in vivo. Previous modeling was based on the concept of an extensive, fluctuating cap of tubulin-GTP to stabilise growing microtubules. A quantitative kinetic model is now presented in which only the terminal layer of the multi-start helical microtubule lattice contains tubulin-GTP molecules, comprising a 'Lateral Cap.' In Monte Carlo numerical simulation, this model readily produces the decisive experimental evidence of microtubule dynamics, and predicts a co-operative mechanism for microtubule transitions. The model also suggests how differing kinetic properties at opposite ends are the result of the intrinsic polarity of the microtubule lattice, reflecting the polarity of the tubulin alpha/beta heterodimer.

Guanosine Triphosphate↗
PubMed1989

Site of carbamoylation of bovine gamma-II-crystallin by potassium [14C]cyanate.

One possible route to cataract formation may be via the carbamoylation of lens proteins due to increased concentrations of cyanate in the body resulting from uraemia associated with renal failure and with severe diarrhoea. Carbamoylation of gamma-II-crystallin, which is found in the lens core, could alter the surface charge network of the molecules, resulting in aggregation, increased light-scattering and hence cataract. We have attempted to locate the site(s) of carbamoylation in gamma-II-crystallin. gamma-II-Crystallin was isolated by gel chromatography and ion-exchange chromatography. gamma-II-Crystallin was then carbamoylated by incubation with potassium [14C]cyanate, followed by citraconylation and digestion with trypsin to give peptides that were separated by high-resolution ion-exchange chromatography. The amino acid compositions of the radioactive peptides were compared with the expected peptide composition for gamma-II-crystallin. The radioactive peptide compositions, which agreed with the theoretical peptides, all matched with the N-terminal region of gamma-II-crystallin and had in common the presence of the N-terminal glycine residue. It appears that the alpha-amino group of the N-terminal glycine was the main site of carbamoylation. This site forms part of the charge network on the surface of gamma-II-crystallin.

Amino Acids↗