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Biomedical subjects

D Sinclair

Publications and source records attributed to D Sinclair.

At least 19 recordsLinked to original sources
PubMed1999

Passage through stationary phase advances replicative aging in Saccharomyces cerevisiae.

Saccharomyces cerevisiae mother cells undergo an aging program that includes morphologic changes, sterility, redistribution of the Sir transcriptional silencing complex from HM loci and telomeres to the nucleolus, alterations in nucleolar architecture, and accumulation of extrachromosomal ribosomal DNA circles (ERCs). We report here that cells starved for nutrients during prolonged periods in stationary phase show a decrease in generational lifespan when they reenter the cell cycle. This shortened lifespan is not transmitted to progeny cells, indicating that it is not due to irreversible genetic damage. The decrease in the lifespan is accompanied by all of the changes of accelerated aging with the notable exception that ERC accumulation is not augmented compared with generation-matched, nonstarved cells. These results suggest a number of models, including one in which starvation reveals a component of aging that works in parallel with the accumulation of ERCs. Stationary-phase yeast cells may be a useful system for identifying factors that affect aging in other nondividing eukaryotic cells.

Biotin↗
PubMed1999

Depression of glutathione content, elevation of CYP2E1-dependent activation, and the principal determinant of the fasting-mediated enhancement of 1,3-dichloro-2-propanol hepatotoxicity in the rat.

The influence of fasting (18 hours) on the hepatotoxicity of 1,3-dichloro-2-propanol (1,3-DCP) and on various hepatic parameters has been assessed in the rat. Fasting produced an enhancement of the hepatotoxicity which was associated with alterations in a variety of hepatic parameters when measured relative to protein content, most notably glutathione (GSH) levels (decrease) and CYP2E1-mediated enzyme activity (increase), two parameters previously identified as being important determinants to the toxicity. Fasting also decreased the liver weight normalized to body weight. When this was taken into account, total liver CYP2E1-mediated enzyme activity was not significantly altered whereas the total liver GSH level was markedly reduced following fasting. These results imply that the reduction in hepatic GSH is the principal determinant of the enhanced susceptibility to 1,3-DCP hepatotoxicity following fasting.

Animals↗
PubMed1999

Behavioral dimensions of adjustment in persons with chronic pain: pain-related anxiety and acceptance.

Through empirical methods we now characterize patients with chronic pain as either dysfunctional, interpersonally distressed, or adaptive copers. Studying factors that differentiate these groups may reveal the behavioral processes that determine adjustment to pain. Subjects for this study were 190 patients referred for treatment of chronic pain. They were classified as dysfunctional (n = 41), interpersonally distressed (n = 28) or adaptive copers (n = 59) based on the Multidimensional Pain Inventory (Kerns, R.D., Turk, D.C. and Rudy, T.E., The West Haven-Yale Multidimensional Pain Inventory (WHYMPI), Pain, 23 (1985) 345-356) and compared on measures of pain-related anxiety and pain acceptance. Our analyses showed that the dysfunctional group reported greater pain-related anxiety and less acceptance of pain than the other groups. Additional analyses, statistically controlling for pain severity and depression, showed that the patient subtypes continued to differ on pain-related anxiety and acceptance. Discriminant function analyses including pain-related anxiety and acceptance correctly classified 72.5% of dysfunctional and 90.9% of adaptive copers. Again, anxiety and acceptance contributed uniquely to classification independent of depression and pain intensity. Pain-related anxiety and acceptance of pain appear to be unique behavioral dimensions of adjustment to chronic pain. Decreasing anxiety and increasing acceptance may 'move' patients with chronic pain from the dysfunctional to the adaptive coper category.

Adaptation, Psychological↗
PubMed1999

The socioemotional development of 5-year-old children of postnatally depressed mothers.

A community sample of depressed and well mothers, recruited at 2 months postpartum and assessed through to 18 months, was followed up at 5 years. The quality of mother-child interactions was assessed, as was the children's behavioural and social adjustment, using maternal reports and observations of child behaviour during free play at school. Several aspects of child outcome were found to be associated with postnatal depression, even when taking account of current adverse circumstances (maternal depression and parental conflict). These included the child's behaviour with the mother, the presence of behavioural disturbance at home, and the content and social patterning of play at school. These associations with postnatal depression were independent of the child's gender. The child's relationship with the mother appeared to be mediated by the quality of infant attachment at 18 months. The mother's behaviour with her child was more affected by current difficulties, in particular by conflict with the child's father. Together these findings suggest that, while maternal behaviour varies with changing circumstances, exposure to maternal depression in the early postpartum months may have an enduring influence on child psychological adjustment.

Child Behavior Disorders↗
PubMed1998

Emergency department observation unit: can it be funded through reduced inpatient admission?

STUDY OBJECTIVE: We sought to test the assumption that an emergency department observation unit can be funded through the reallocation of resources made available through the unit's impact in reducing inpatient admissions and facilitating bed closures. METHODS: We conducted our study in a tertiary care center ED with 46,000 visits annually. For a 3-month period, all patients admitted to the hospital through the ED were screened by an emergency physician for suitability for admission to an observation unit. Any patient in the hospital for 3 days or less who did not undergo surgery or other inpatient procedure, and who was admitted through the ED, was considered a candidate for the observation unit. RESULTS: Of 1,840 admissions, 147 patients met the admission criteria. Only 48 (32.2%) could have been treated in an observation unit, and these patients were not admitted to any single unit in high frequency. The potential savings from inpatient bed closures would only have amounted to 1.68 full-time equivalents-not enough to staff a 4-bed observation unit, which would require 5 full-time equivalents. CONCLUSION: Because of the diffuse and inconsistent effect such a unit had on inpatient bed use, funding for an ED observation unit at our institution could not be justified on the basis of the closure of inpatient beds and transfer of resources.

Adolescent↗
PubMed1998

Aging in Saccharomyces cerevisiae.

The budding yeast Saccharomyces cerevisiae divides asymmetrically, giving rise to a mother cell and a smaller daughter cell. Individual mother cells produce a finite number of daughter cells before senescing, undergoing characteristic changes as they age such as a slower cell cycle and sterility. The average life span is fixed for a given strain, implying that yeast aging has a strong genetic component. Genes that determine yeast longevity have highlighted the importance of such processes as cAMP metabolism, epigenetic silencing, and genome stability. The recent finding that yeast aging is caused, in part, by the accumulation of circular rDNA molecules has unified many seemingly disparate observations.

Animals↗
PubMed1998

Effects of postnatal depression on children's adjustment to school. Teacher's reports.

BACKGROUND: Little is known of the behavioural adjustment of children of postnatally depressed mothers. Previous studies have relied on maternal reports, and have produced inconsistent findings. METHOD: In a prospective, longitudinal study of the five-year-old children of a community sample of postnatally depressed and well women, evidence was collected concerning the children's adjustment in the context of school, teachers being asked to complete questionnaires after the children had finished their first term. RESULTS: Family social class and the child's gender had the most pervasive influences on adjustment. However, both postnatal and recent maternal depression were associated with significantly raised levels of child disturbance, particularly among boys and those from lower social class families. CONCLUSIONS: The findings indicate a persistent effect of postnatal depression on child adjustment. They highlight the need for resources devoted to supporting mothers of young children and particularly routine screening and treatment for postnatal mood disorder.

Adaptation, Psychological↗
PubMed1998

Bacteremia in nursing home patients. Prevalence among patients presenting to an emergency department.

OBJECTIVE: To measure the prevalence of bacteremia and any correlation between signs and symptoms, risk factors, and laboratory data in elderly patients. DESIGN: Prospective analysis. All patients were contacted by the study nurse at 48 hours and 7 days after study entry. SETTING: Adult tertiary care hospital with an emergency department managing 48,000 visits yearly in a metropolitan area of 250,000. PARTICIPANTS: Members of the study population referred to the emergency department for medical or surgical problems. Of 113 nursing home patients, blood culture results were available for 111. MAIN OUTCOME MEASURES: Blood cultures were obtained by standard protocol. Demographic and medical information was collected from the medical record. Three groups of patients were compared with respect to symptoms, risk factors, laboratory data, and outcome. RESULTS: Group 1 (n = 86) had two sets of negative blood cultures. Group 2 (n = 10) had true-positive cultures. Group 3 (n = 15) had false-positive cultures of Staphylococcus epidermidis. The prevalence of bacteremia was 9.8% in the study population. No risk factors were predictive of bacteremia. Great variation in signs and symptoms were noted in all three groups, none correlating with bacteremia. Although seven of the 10 patients with positive cultures were febrile, this association did not reach statistical significance. All groups had high admission (> 50%) and mortality (20% to 37%) rates. CONCLUSIONS: The prevalence of bacteremia in the nursing home population presenting to the emergency department was 9.8%. The symptoms and signs of bacteremia in this population were variable and nonspecific. The high rate of false-positive cultures in this setting is of concern.

Adult↗
PubMed1997

Devolution to whom?

Explore the source record for details and available documents.

Delivery of Health Care, Integrated↗
PubMed1997

Campylobacteriosis in New Zealand: results of a case-control study.

STUDY OBJECTIVE: To identify and assess the contributions of major risk factors for campylobacteriosis in New Zealand. DESIGN: Case-control study. Home interviews were conducted over nine months using a standardised questionnaire to assess recent food consumption and other exposures. SETTING: Four centres in New Zealand with high notification rates of campylobacter infections--Auckland, Hamilton, Wellington, and Christchurch. PARTICIPANTS: Case patients were 621 people notified between 1 June 1994 and 28 February 1995 as having campylobacter infection. Control subjects were selected randomly from telephone directories, and were matched 1:1 with case patients in relation to sex, age group, and home telephone prefix. RESULTS: Risk of campylobacteriosis was strongly associated with recent consumption of raw or undercooked chicken (matched odds ratio 4.52, 95% confidence interval 2.88, 7.10). There was also an increased risk with chicken eaten in restaurants (matched odds ratio 3.85; 2.52, 5.88). Recent consumption of baked or roasted chicken seemed to be protective. Campylobacteriosis was also associated with recent overseas travel, rainwater as a source of water at home, consumption of raw dairy products, and contact with puppies and cattle, particularly calves. CONCLUSIONS: Improperly cooked chicken seems to be associated with a large proportion of campylobacteriosis in New Zealand. Thorough cooking of chicken in homes and restaurants could reduce considerably the incidence of this disease.

Campylobacter Infections↗
PubMed1995

HIV in the accident and emergency department.

This article is intended as an introduction to some of the issues which arise from the increasing incidence in the UK of human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS). It is not possible fully to address, nor offer answers to, all of these issues. HIV and AIDS present many challenges to nurses. It tests not only our skills and methods of practice, but confronts our feelings about people whose lifestyles and behaviours may be different from our own (Lert & Marne 1992; McGrath et al 1993); it has also prompted us to alter our awareness and knowledge of medical, nursing and infection control issues. Hopefully this article will serve to stimulate reflection, thought and discussion as well as generating further, more specific papers of relevance to the Accident and Emergency nurse.

Emergency Nursing↗
PubMed1994

Segmenting radiographs of the hand and wrist.

The work presented in this paper concerns the development of computer-based techniques for the segmentation of hand-wrist radiographs and in particular those obtained for the TW2 method for the assessment of skeletal maturity (bone age). The segmentation method is based on the concept of regions and it consists of region growing and region merging stages. A bone extraction stage follows, which labels regions as either bone or background using heuristic rules based on the grey level properties of the scene. Finally, a technique is proposed for the segmentation of bone outlines which helps in identifying conjugated bones.

Adolescent↗
PubMed1994

Hidden alcohol abuse among women.

Seven years ago the authors examined 64 consecutive female out-patients with macrocytosis (erythrocyte mean cell volume > or = 100 fl). The cause remained undetermined in 23 (35.9%). Their patient histories were evaluated in 1992, and the new highly specific alcohol marker, serum carbohydrate-deficient transferrin, from the frozen sera taken during the initial study was examined. It was elevated in 6 of the 23 women. Furthermore, four of these six had visited the health centre after 1985 and they all had clinical records indicative of alcohol problems. Because early intervention has proved to be effective, information about the risks of alcohol abuse (intervention) should be given to women with suspect alcohol-induced symptoms or signs.

Adult↗
PubMed1994

Myocardial infarction. Considerations for geriatric patients.

Myocardial infarction is common among the elderly. Presentation is often atypical, and symptoms include confusion, weakness, chest pain, dyspnea, and vomiting. Serial electrocardiograms and cardiac enzyme determination lead to diagnosis. Postmyocardial treatments include acetylsalicylic acid, beta-blockers, nitrates, and angiotensin-converting enzyme inhibitors. Thrombolytic agents are safe and useful. Angioplasty and cardiac surgery should be considered for certain patients.

Adrenergic beta-Antagonists↗