Search PubMed⌕ Search

Biomedical subjects

S Goodwin

Publications and source records attributed to S Goodwin.

At least 37 records · Page 2Linked to original sources
PubMed2000

Characterization, seasonal occurrence, and diel fluctuation of poly(hydroxyalkanoate) in photosynthetic microbial mats.

In situ poly(hydroxyalkanoate) (PHA) levels and repeating-unit compositions were examined in stratified photosynthetic microbial mats from Great Sippewissett Salt Marsh, Mass., and Ebro Delta, Spain. Unlike what has been observed in pure cultures of phototrophic bacteria, the prevalence of hydroxyvalerate (HV) repeating units relative to hydroxybutyrate (HB) repeating units was striking. In the cyanobacteria-dominated green material of Sippewissett mats, the mole percent ratio of repeating units was generally 1HB:1HV. In the purple sulfur bacteria-dominated pink material the relationship was typically 1HB:2HV. In Sippewissett mats, PHA contributed about 0.5 to 1% of the organic carbon in the green layer and up to 6% in the pink layer. In Ebro Delta mats, PHA of approximately 1HB:2HV-repeating-unit distribution contributed about 2% of the organic carbon of the composite photosynthetic layers (the green and pink layers were not separated). Great Sippewissett Salt Marsh mats were utilized for more extensive investigation of seasonal, diel, and exogenous carbon effects. When the total PHA content was normalized to organic carbon, there was little seasonal variation in PHA levels. However, routine daily variation was evident at all sites and seasons. In every case, PHA levels increased during the night and decreased during the day. This phenomenon was conspicuous in the pink layer, where PHA levels doubled overnight. The daytime declines could be inhibited by artificial shading. Addition of exogenous acetate, lactate, and propionate induced two- to fivefold increases in the total PHA levels when applied in the daylight but had no effect when applied at night. The distinct diel pattern of in situ PHA accumulation at night appears to be related, in some phototrophs, to routine dark energy metabolism and is not influenced by the availability of organic nutrients.

Alkanes↗
PubMed2000

Methane production and release from two New England peatlands.

The rate of methane production and release to the atmosphere was determined for two New England peat bogs. Methane production rates from peat sediments, which were measured down to depths of 150 cm, ranged from 1 to 15 micromoles per liter per hour. The highest rates of methane production occurred at depths of 60-100 cm. Methane release from these same peats was quantified from various habitats on the bog using gas collection chambers. The chambers enclose a two-liter volume and cover an area of 0.02 m2. Methane accumulation in the chambers was measured for periods of up to 18 days. Methane release was related to pH and habitat zone. The lowest rates of methane release were from those portions of the bogs that had pH values below 5.0. Peak methane release occurred during or immediately after ice melt in both wetlands with release rates as high as 34 mmoles/m2/d. The overall estimate of yearly release of methane from these bog systems is 2,900 and 14,900 moles per year for Arcadia and Hawley Bogs respectively. Both of these bogs have pH environments close to the lowest limit for methanogenesis, and small differences in pH values can have a large impact on both the rate of methane production and the rate of methane release to the atmosphere.

Anaerobiosis↗
PubMed2000

A personalised approach to cardiac rehabilitation.

Patients' beliefs about their myocardial infarction will affect their physical and emotional recovery. An individualised, behavioural approach to rehabilitation aims to treat the patient as an adult learner who participates fully in negotiating priorities for rehabilitation. Initiating rehabilitation advice in the very early stages post-AMI requires the use of specific nursing interventions.

Humans↗
PubMed1999

Transforming growth factor-beta type II receptor confers tumor suppressor activity in murine renal carcinoma (Renca) cells.

OBJECTIVES: To demonstrate that the introduction of the transforming growth factor-beta (TGF-beta) type II receptor (TbetaR-II) decreases tumorigenicity in an aggressive murine renal carcinoma line, Renca. These cells do not express TbetaR-II. Because the presence of TbetaR-II in benign epithelial cells is ubiquitous, the ability to restore tumor suppressor activity in the Renca cell line with its introduction would elucidate the role of TbetaR-II as a tumor suppressor gene. METHODS: Renca cells were stably transfected with a retrovirus-mediated TbetaR-II expression vector. In vitro sensitivity to growth inhibitory effect of TGF-beta was assessed by the 3H-thymidine incorporation assay. For in vivo testing, xenograft tumors were produced by subcutaneous injection of tumor cells into immunodeficient nude mice. The tumorigenicity of these TbetaR-II transfected cells was tested. Wild-type Renca cells and cells transfected with the control vector were also tested for comparison. RESULTS: Expression of TbetaR-II mRNA was evident in Renca cells after transfection with the TbetaR-II construct. In vitro sensitivity to the growth inhibitory effect of TGF-beta was restored. This effect of TGF-beta was reversible with a neutralizing antibody specific for the extracellular domain of TbetaR-II. Xenografts grown from TbetaR-II transfected cells were significantly smaller, weighed less, and developed tumors later than those developed from wild-type Renca cells and those transfected with the control vector. CONCLUSIONS: We conclude that TbetaR-II is a central mediator of tumorigenicity in Renca cells. As with other tumor suppressor genes, the loss of TbetaR-II expression allows for the development of an aggressive phenotype.

Animals↗
PubMed1998

Temporal trends in coal workers' pneumoconiosis prevalence. Validating the National Coal Study results.

Evidence from four successive rounds of the National Study of Coal Workers' Pneumoconiosis indicates diminishing prevalence of coal workers' pneumoconiosis (CWP) from 1969 to 1988. However, methodological inconsistencies across surveys have raised concerns. This study confirms the reported downward trend in CWP prevalence, utilizing a standardized methodological approach. A single team of three x-ray readers using the 1980 International Labour Office classification independently re-evaluated 3143 Appalachian-region cases to derive overall, tenure- and age-specific prevalences. Prevalence of small rounded opacities declined, with 12.7% in Round 1, 11.2% in Round 2, 3.0% in Round 3, and 3.9% in Round 4. These findings support the National Institute for Occupational Safety and Health's recommendation of a reduced exposure limit of 1 mg/m3 because the present coal dust standard does not sufficiently protect miners against adverse health effects over a working lifetime of exposures.

Coal Mining↗
PubMed1998

Nonulcer dyspepsia and Helicobacter pylori, with comment on posteradication symptoms.

In two London hospitals during five months in 1997, among patients referred for esophago-gastroduodenoscopy, 250 complained of dyspepsia for more than two days per week. Of these, 190 gave informed consent to enter a study of H. pylori infection in nonulcer dyspepsia, but only 42 (22%) were found to have H. pylori infection without a peptic ulcer. At the time of this interim report, of these patients, 26 had been treated with omeprazole, amoxicillin, and clarithromycin, four weeks had elapsed since treatment, and H. pylori had been eradicated. Of these 26 patients, 15 (58%) had lost nearly all their symptoms. This is the first report of loss of symptoms in patients with nonulcer dyspepsia after treatment with omeprazole, amoxicillin and clarithromycin with early follow-up after four weeks. However, this was not a placebo-controlled study and the number of patients was small, so it is not possible to conclude whether H. pylori could be one cause of nonulcer dyspepsia. The increasing incidence of posteradication esophagitis is discussed as is the possible need for more sophisticated management of nonulcer dyspepsia.

Adult↗
PubMed1998

Absence of expression of transforming growth factor-beta type II receptor is associated with an aggressive growth pattern in a murine renal carcinoma cell line, Renca.

Transforming growth factor-beta1 (TGF-beta1) inhibits the proliferation of many cancer cells. However, tumor cells frequently become resistant to this inhibitory effect due to the absence of TGF-beta receptor (TbetaR) expression. This study reports the nature of TGF-beta sensitivity in an aggressive murine renal carcinoma cell line, Renca, investigated in a series of experiments. The growth of Renca cells, in tissue culture, was not sensitive to the inhibitory effect of TGF-beta1 with doses ranging from 0.1 to 10 ng./ml., nor was this cell line sensitive to the effect of TGF-beta1 in inducing the expression of plasminogen activator inhibitor-I. Renca cells expressed TGF-beta1 mRNA and protein, as determined by RT-PCR and ELISA, respectively. The level of TGF-beta1 production by Renca cells was moderate, thus eliminating the possibility that endogenous TGF-beta1 production might be masking the effect of TGF-beta sensitivity. Furthermore, Renca cells expressed TbetaR-I mRNA, but did not express TbetaR-II mRNA, suggesting that the absence of this receptor may be the cause of TGF-beta insensitivity. Additionally, a vector containing the TbetaR-II cDNA was transiently transfected into Renca cells. The inhibitory effect of TGF-beta1 was introduced in Renca cells after transfection with this receptor. At the same time, the growth rate of these cells diminished significantly when compared with that of the wild type Renca cells, as judged by the rate of [3H]-thymidine incorporation in the absence of any exogenous TGF-beta1. These observations demonstrated that Renca cells lack the functional TbetaR-II and suggest that their aggressive growth pattern is due, at least in part, to their insensitivity to TGF-beta.

Animals↗
PubMed1997

Vertical transmission of toxoplasma by human immunodeficiency virus-infected women.

OBJECTIVE: Our goal was to determine the frequency of mother-to-child transmission of Toxoplasma gondii from human immunodeficiency virus-infected mothers who are also chronically infected with T. gondii. STUDY DESIGN: One hundred thirty-eight women were entered into a prospective study of human immunodeficiency virus infection in pregnancy. The women were seen at enrollment, during the third, sixth, and eighth months of pregnancy (except those enrolled later in pregnancy or at delivery), at 2 and 6 months post partum, and at 6-month intervals thereafter through 4 years after delivery. Standardized interviews and physical examinations were performed, and blood was drawn at each visit. Toxoplasma serologic testing was performed on the sample drawn earliest in pregnancy; the Sabin-Feldman dye test for immunoglobulin G antibodies and enzyme-linked immunoassays for immunoglobulins M, A, and E were used. Univariate analysis for categoric variables was performed with chi2 and two-tailed Fisher exact tests, and for continuous variables the Student t test was used. Statistical Analysis System procedures were followed. RESULTS: Twenty-eight of 138 (20.2%) women who had positive test results for human immunodeficiency virus had positive findings of the Sabin-Feldman dye test. Serologic status for T. gondii did not correlate with age, immune status, parity, or drug use. One of 27 children born to women who were seropositive for both human immunodeficiency virus and T. gondii (one child's serologic status for T. gondii was unknown) had Sabin-Feldman dye test antibodies beyond age 6 months (3.7%, 95% confidence interval 0.09% to 18.9%). Among the cohort of human immunodeficiency virus-infected mothers the rate of mother-to-child human immunodeficiency virus transmission did not vary with maternal Toxoplasma status. However, with sample sizes of 28 and 110, respectively, for the mothers who were T. gondii seropositive and seronegative, the power to detect a difference in the human immunodeficiency virus transmission rate between these groups would be relatively small. CONCLUSIONS: Transmission of T. gondii from a chronically infected mother can occur in the setting of a human immunodeficiency virus infection, but this is not a common phenomenon. In a small cohort of human immunodeficiency virus-infected women we did not observe its occurrence among those without severe immunocompromise.

Adult↗
PubMed1997

Non-cardiac chest pain: why was a brief intervention apparently ineffective?

BACKGROUND: Patients who present with chest pain but have normal coronary angiography and who are told by their cardiologist that they do not have heart disease, have a poor symptomatic, psychological and quality of life outcome and remain concerned about a serious cause of their symptoms. They frequently complain they have not had enough information. The study aimed to test the effectiveness and acceptability of a brief psychological intervention based on cognitive behavioural principles. METHODS: Consecutive patients with chest pain and normal angiograms were assessed and invited to take part in a randomized controlled evaluation. The intervention consisted of an individualized information and discussion session by a specially trained cardiac nurse, together with a handout and cassette providing information and advice and telephone follow-up to discuss progress, answer questions and reiterate advice. RESULTS: The treatment proved to be unacceptable to some patients and there was no evidence of efficacy. CONCLUSIONS: Implications for the preparation of patients undergoing angiography and for the timing and delivery of information and advice following a negative result are discussed.

Analysis of Variance↗
PubMed1996

Neurologic status of human immunodeficiency virus 1-infected infants and their controls: a prospective study from birth to 2 years. Mothers and Infants Cohort Study.

OBJECTIVE: To determine the timing, extent, severity, and persistence of neurologic abnormalities in children with perinatally acquired human immunodeficiency virus 1 (HIV-1) infection compared with similar uninfected children of HIV-1-infected women and control children. METHODS: Serial neurologic examinations and head circumference measurements were performed on a cohort of HIV-1-infected children born to HIV-1-infected women, seroreverting children born to HIV-1-infected women, and control children born to uninfected women. Examination data from 32 HIV-1-infected children, 99 reverters, and 116 control children were summarized by eight neurologic domains. Data were analyzed by longitudinal analysis. RESULTS: Reverter children were not different from control children in neurologic function for any of the eight domains or head circumference. HIV-1-infected children had significantly more neurologic problems than the control and reverter children for seven of the eight domains. The HIV-1-infected children were further classified by whether they had acquired immunodeficiency syndrome (AIDS)-defining clinical conditions (other than lymphoid interstitial pneumonitis) in the first 24 months of life (the AIDS-opportunistic infection group) or did not (the infected-other group). Neurologic abnormalities were early, severe, pervasive, and persistent in the AIDS-opportunistic infection group, and nearly all in this group had head circumference measurements below the 10th percentile. The infected-other group had no statistically significant differences from the uninfected children, although individual children in the infected-other group had some abnormalities. CONCLUSIONS: In utero exposure to HIV-1 without infection seems to have no negative impact on neurologic function in children in the first 2 years of life. Among children with perinatally acquired HIV-1 infection, the most severe and pervasive neurologic problems occur in those children who have early serious HIV-1 clinical disease. Most children without serious AIDS-defining clinical conditions in the first 2 years of life are also free from serious neurologic problems during that period.

AIDS-Related Opportunistic Infections↗
PubMed1995

Commissioning for health.

The NHS internal market offers community nurses unprecedented opportunity to achieve, through influencing the purchasing process, real improvements in health and health care. Shirley Goodwin outlines what she, as a purchaser, looks for when she commissions community nursing services.

Community Health Nursing↗
PubMed1994

Purchasing effective care for parents and young children.

The extension of GP fundholding and the focus on the primary health care team means that GPs have become major players in the purchasing of child and family community nursing services. Shirley Goodwin explores what effective purchasing by GP fundholders of health visiting services might entail and the principles which should inform their decisions.

Community Health Nursing↗