Search PubMed⌕ Search

Biomedical subjects

J Hunt

Publications and source records attributed to J Hunt.

At least 127 records · Page 7Linked to original sources
PubMed1993

Work-site smoking policies: their population impact in Washington State.

This article presents data from a population-based, random-digit dialing telephone survey of 1228 employed adults in Washington State, conducted 1989 through 1990. Eighty-one percent of men and 91% of women reported work-site smoking restrictions. Employees in work sites with no-smoking policies were less likely to be current smokers; men in work sites with policies restricting smoking smoked fewer cigarettes on both workdays and nonworkdays. Forty-eight percent of male and 53% of female smokers reported reduced smoking as a result of work-site policy. Work-site smoking policies, intended to protect against smoke exposure, may also reduce employee smoking.

Adult↗
PubMed1993

Identification of an mRNA species which encodes a voltage-operated Ca2+ channel in rat liver mRNA.

cDNA which encodes part of the alpha 1-subunit of the rabbit skeletal muscle L-type voltage-operated Ca2+ channel (VOCC cDNA) was employed to search for the presence in whole liver and hepatocytes of poly (A+) RNA homologous to mRNA which encodes VOCCs. Such homologous mRNA would be a candidate for mRNA which encodes the putative hepatocyte receptor-activated Ca2+ inflow system (RACIS). Northern blot analysis showed that poly (A+) RNA prepared from intact liver tissue, but not hepatocytes, contained a poly (A+) RNA species comparable in size to that which encodes the alpha 1-subunit of the L-type VOCC. It is concluded (a) that hepatocytes do not possess VOCCs or that the levels of VOCC poly(A+) RNA in hepatocytes are too low to be detected by Northern analysis and (b) that another cell type present in liver tissue does possess a VOCC. In a low stringency screen of a rat liver cDNA library employing VOCC cDNA as a probe, seven positive cDNA clones were obtained. While regions of the 2.3 kb cDNA insert from one of these clones showed sequence similarities with regions of VOCC cDNA, the 2.3 kb sequence did not appear to encode a Ca2+ channel. The present results suggest that the approach of low stringency cDNA library screening is unlikely to allow isolation of RACIS cDNA.

Animals↗
PubMed1993

Collaboration in coronary heart disease prevention.

Health visitors are ideally placed in primary care to offer effective dietary and life-style advice as part of a team approach to coronary heart disease prevention, write Alan Jones et al. Results from a dietary and life-style intervention trial programme suggest that dietitians, who are limited in numbers, should be used as a resource to provide expert dietary advice and training to the more numerous health visitors. In this way CHD risk factor identification can be developed into effective intervention.

Adult↗
PubMed1992

Purification and properties of milk xanthine dehydrogenase.

Milk xanthine oxidase (XO) has been prepared in a dehydrogenase form (XDH) by purifying the enzyme in the presence of 2.5 mM dithiothreitol. Unlike XO, which reacts rapidly only with oxygen and not with NAD, the XDH form of the enzyme reacts rapidly with NAD. XDH has a turnover number for the NAD-dependent conversion of xanthine to urate of 380 mol/min/mol at pH 7.5, 25 degrees C, with a Km = < or = 1 microM for xanthine and a Km = 7 microM for NAD, but has very little O2-dependent activity. There is evidence that the two forms of the enzyme have different flavin environments: XDH stabilizes the neutral form of the flavin semiquinone and XO does not. Further, XDH binds the artificial flavin 8-mercapto-FAD in its neutral form, shifting the pK of this flavin by 5 pH units, while XO binds 8-mercapto-FAD in its benzoquinoid anionic form. XDH can be converted back to the XO form by the addition of three to four equivalents of the disulfide-forming reagent 4,4'-dithiodipyridine, suggesting that, in the XDH form of the enzyme, disulfide bonds are broken; this may cause a conformational change which creates a binding site for NAD and changes the protein structure near the flavin.

Animals↗
PubMed1992

Evaluation of the International Society for Heart Transplantation (ISHT) grading of pulmonary rejection in 100 consecutive biopsies.

Heart-lung and lung transplantation are accepted treatments for patients with end-stage pulmonary vascular disease or parenchymal lung disease. Survival rates for heart-lung and lung transplantation are lower than those for heart transplantation alone. The 5-year actuarial survival for heart-lung transplantation has been 41% largely due to rejection and infection remaining as the limiting factors for long-term survival. A standardized nomenclature for the histological grading of pulmonary rejection was formulated by the International Society for Heart Transplantation (ISHT) in July 1990. Infection, however, is a major problem in the histological assessment of lung recipient biopsies, potentially limiting the usefulness of such a classification. In this study, 100 consecutive transbronchial biopsies (TBBs) from lung transplant recipients were analysed, together with microbiological and serological data, in order to evaluate the proposed ISHT grading system for pulmonary rejection and the importance of concomitant infections in the histological interpretation of TBBs.

Adolescent↗
PubMed1992

Asthma under-recognition and under-treatment in an Australian community.

In a study in south-western Sydney, we examined asthma symptoms in a random sample of 4239 schoolchildren aged five-12 years. The prevalence of current wheeze and cough was 17.1% (95% CI 16.0-18.2%). Interviews were conducted with the parents of all 214 symptomatic children from two of the six schools. Only 60% of these children had ever been labelled as asthma, and only 20% were using appropriate asthma treatment. Fewer than 6% had ever had their airway function assessed. There was a socio-economic difference, with better levels of asthma recognition and management in children attending the school in the more affluent region. The findings suggest that asthma recognition, assessment and management in the Australian community, as in New Zealand and the UK, may need to be improved.

Asthma↗
PubMed1991

Coexisting macrophage-associated fibrin formation and tumor cell urokinase in squamous cell and adenocarcinoma of the lung tissues.

Mechanisms of coagulation activation in situ were studied by means of immunohistochemical techniques applied to surgically resected primary adenocarcinomas and squamous cell carcinomas of the lung. Findings in these two histologic types were similar. Double-labeling techniques using macrophage-specific antibody together with antibody to either tissue factor, factor VII, factor X, or factor V revealed coincident staining for each of these coagulation factors on tumor-associated macrophages. Staining of tumor cells for these factors was rare and inconsistent. Both macrophages and fibroblasts in the tumor connective tissue stained for the a subunit of factor XIII. Fibrinogen was abundant throughout the tumor connective tissue, but staining for fibrin and D-dimer cross-linked sites of fibrin was restricted to areas adjacent to macrophages, indicating that thrombin was generated in association with tumor macrophages but not with tumor cells. By contrast, tumor cells stained diffusely for urokinase-type plasminogen activator and focally for thrombomodulin. These findings contrast with those reported previously for small cell carcinoma of the lung and suggest that coagulation activation in adenocarcinoma and squamous cell carcinoma of the lung may occur indirectly through activation of certain host cells such as macrophages. By contrast, tumor cell plasminogen activator may mediate certain aspects of the malignant phenotype in these tumor types.

Adenocarcinoma↗
PubMed1991

Cellular localization of activated factor X by Xa-specific probes.

A probe, recombinant antistasin, that reacts specifically with the activated form of factor X (Xa) was used in immunohistochemical procedures to detect cellular sites of Xa generation within intact tissues. Factor Xa was detected on tumor cells in small cell carcinoma of the lung, renal cell carcinoma, and malignant melanoma. Tumor-associated macrophages (but not tumor cells) expressed Xa in adenocarcinoma and squamous cell carcinoma of the lung, and Hodgkin's disease. Factor Xa in these locations corresponded to evidence reported previously for an intact coagulation pathway and thrombin formation associated with these tumor cells and macrophages. By contrast, only rare connective tissue cells stained for Xa in breast and colon cancer, tumor types shown previously to lack an intratumoral coagulation pathway and thrombin generation, and in normal liver, lung, breast, kidney, and placental tissues. Hepatocytes did not stain. These results suggest that such probes may be useful for studying the activation state of cell-associated factor X in situ within intact tissues.

Factor Xa↗
PubMed1991

The emotional phases of marital separation: an empirical investigation.

The emotional process of marital separation was investigated via the application of Bowlby's theory of loss. Physical separation was found to entail the three phases--wish to recover the lost object, disorganization, and reorganization--proposed by Bowlby. Length of time separated appeared the most powerful factor in emotional resolution. The clinical implications of the findings are discussed.

Adaptation, Psychological↗
PubMed1991

The cytological recognition of African siderosis on bone smears.

Eight cases of African siderosis primarily recognized on cytological smears are presented and discussed. All the smears were obtained from Jamshidi needle biopsies of vertebral bodies. Six cases showed siderosis only, while a seventh showed two pathological processes on one slide, namely metastatic keratinizing squamous carcinoma and siderosis. The remaining case showed cytological evidence of tuberculosis and siderosis. All cases were histologically confirmed, an additional feature in two cases being osseous tuberculosis which was not evident on the cytological smears. A search of the literature failed to reveal any report on the cytological recognition of this disease, or its association with tuberculosis.

Adult↗
PubMed1991

Attitudes towards gamete donation among couples undergoing in vitro fertilization.

The attitudes of 234 anonymous couples undergoing in vitro fertilization toward sperm and oocyte donation were explored by questionnaire. All the questionnaires were returned of which 222 (95%) were complete and analysed. A high proportion of couples found the use of donor sperm acceptable for therapeutic, diagnostic and treatment purposes (77%, 90% and 97% respectively) and 72%, 84% and 90% respectively were willing to donate oocytes for these purposes. Of potential oocyte donors 41% would agree to nonanonymous donation, 12% would wish to meet the recipient couple and although only 4% wanted to choose the recipient, a quarter of the couples would prefer a relative or friend as the recipient. Provision of nonidentifying information about the donor to the recipient couple was acceptable to almost 70% whereas 40% found giving the same information to the child acceptable.

Adult↗
PubMed1991

Comparative and interactive in vivo effects of tumor necrosis factor alpha and endotoxin.

A comparative and interactive analysis of the effects of tumor necrosis factor alpha (TNF) and endotoxin (ETX) on selected hemodynamic and glucoregulatory alterations was performed in conscious, unrestrained, adult male Holtzman rats. Rats with indwelling carotid artery and jugular vein cannulae were administered intravenous (i.v.) bolus injections of either (1) ETX at 1.55 or 30 mg/kg; (2) TNF at 0.1, 0.5, or 1.0 mg/kg; or (3) TNF plus ETX as a low dose co-treatment at 0.1 mg/kg plus 1.55 mg/kg, respectively. Control groups received either saline or heat-inactivated TNF. TNF induced a lethal response such that 1.0 mg/kg resulted in five out of six deaths within 6 hr. Elevated pulse rates, early hyperglycemia, late hypoglycemia, hyperlactacidemia, hypoinsulinemia, and elevated catecholamine concentrations were evident after injection of 1.0 mg/kg TNF. The pathophysiological alterations observed after 1.0 mg/kg TNF were comparable to the changes observed after the administration of a highly lethal, 30 mg/kg dose of ETX (six out of six deaths within 24 hr). Co-treatment with low doses of TNF plus ETX resulted in the rapid demise of the rats, resulting in six out of six deaths within 4 hr. The resultant shocklike state was accompanied by significant hypotension, hyperglycemia and hyperlactacidemia, similar to the changes induced by highly lethal doses of TNF or ETX alone. This study supports the involvement of TNF in the pathogenesis of gram-negative septic shock and documents the hemodynamic and glucoregulatory alterations which accompany the exacerbated shocklike state induced after co-treatment with separately, minimally lethal doses of TNF plus ETX.

Animals↗
PubMed1990

Isolation of four forms of acetone-induced cytochrome P-450 in chicken liver by h.p.l.c. and their enzymic characterization.

The purpose of this study was to purify and characterize the forms of cytochrome P-450 induced in chicken liver by acetone or ethanol. Using high performance liquid ion-exchange chromatography, we were able to isolate at least four different forms of cytochrome P-450 which were induced by acetone in chicken liver. All four forms of cytochrome P-450 proved to be distinct proteins, as indicated by their N-terminal amino acid sequences and their reconstituted catalytic activities. Two of these forms, also induced by glutethimide in chicken embryo liver, appeared to be cytochromes P450IIH1 and P450IIH2. Both of these cytochromes P-450 have identical catalytic activities towards benzphetamine demethylation. However, they differ in their abilities to hydroxylate p-nitrophenol and to convert acetaminophen into a metabolite that forms a covalent adduct with glutathione at the 3-position. Another form of cytochrome P-450 induced by acetone is highly active in the hydroxylation of p-nitrophenol and in the conversion of acetaminophen to a reactive metabolite, similar to reactions catalysed by mammalian cytochrome P450IIE. Yet the N-terminal amino acid sequence of this form has only 30-33% similarity with cytochrome P450IIE purified from rat, rabbit and human livers. A fourth form of cytochrome P-450 was identified whose N-terminal amino acid sequence and enzymic activities do not correspond to any mammalian cytochromes P-450 reported to be induced by acetone or ethanol.

Acetaminophen↗
PubMed1990

The transposable element Uhu from Hawaiian Drosophila--member of the widely dispersed class of Tc1-like transposons.

We report the complete nucleotide sequence of the transposable element Uhu from the vicinity of the alcohol dehydrogenase (Adh) gene of Drosophila heteroneura (an endemic Hawaiian Drosophila). The complete element is about 1650 base-pairs (bp) long, has 46-50 base-pair inverse imperfect repeats at it's ends, and contains a large open reading frame potentially encoding a 192 amino acid protein. We demonstrate that Uhu belongs to a class of transposable elements which includes Tc1 from Caenorhabditis elegans, Barney from Caenorhabditis briggsae, and HB1 from Drosophila melanogaster. All of these elements share significant sequence similarity, are approximately 1600 base pairs long, have short inverse terminal repeats (ITRs), contain open reading frames (ORFs) with significant sequence identity, and appear to insert specifically at TA sequences generating target site duplications.

Alcohol Dehydrogenase↗