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Biomedical subjects

S Thomas

Publications and source records attributed to S Thomas.

At least 415 records · Page 23Linked to original sources
PubMed1996

In vitro investigations of a new hydrogel dressing.

The aim of this study was to investigate in vitro the fluid-handling properties of a new hydrogel dressing (Aquaform) and to compare these with the fluid-handling properties of a commonly used hydrogel dressing (Intrasite Gel). The results of laboratory tests indicate that the new hydrogel can absorb substantial amounts of fluid from simulated wet wounds and donate substantial amounts of fluid to simulated dry or necrotic wounds. The amount of fluid exchanged in both wound types for the new hydrogel was similar to that for Intrasite Gel.

Bandages↗
PubMed1996

Dose-dependent effects of recombinant human growth hormone on biochemical markers of bone and collagen metabolism in adult growth hormone deficiency.

Administration of growth hormone (GH) to patients with growth hormone deficiency (GHD) has beneficial effects, but so far has been employed only empirically. We have, therefore, investigated the dose-dependent effect of GH on target tissue by studying biochemical markers of bone and collagen turnover in GHD. Then patients with GHD (nine males and one female aged 21-43 years, mean age 28 years) participated in the study. Growth hormone deficiency was defined as a peak serum GH response of less than 15 mU/l in two provocation tests. After a 4-week run-in period, the study population received increasing doses of GH at 4-week intervals (1, 2 and 4 U/m2). Blood samples were collected in the fasting state at 7.00 h on the last day of each period and assayed for serum levels of osteocalcin (S-BGP), bone alkaline phosphatase (B-ALP), C-terminal propeptide of type I collagen (S-PICP), carboxy-terminal pyridinoline cross-linked telopeptide of type I collagen (S-ICTP) and N-terminal propeptide of type III collagen (S-PIIINP). Following replacement therapy, serum insulin-like growth factor I and insulin-like growth factor binding protein 3 increased sequentially with time (p < 0.001 and p < 0.001, MANOVA) and the values were elevated significantly over baseline levels after treatment with 1 U/m2. Serum BGP values were below normal at the start of the study and increased gradually following GH treatment to levels in the low-normal range. Baseline values for serum bone alkaline phosphatase (B-ALP), PICP and PIIINP were within the normal range. The collagen parameters increased with GH replacement (p < 0.001, MANOVA) to levels above normal, whereas B-ALP stayed within normal limits. Serum ICTP values were elevated above the normal range at baseline, indicating increased bone resorption in GHD. A linear increase in values was observed with GH treatment (p < 0.001, MANOVA). Serum ICTP did not correlate significantly with the bone formative parameters but was correlated positively to PIIINP. The sensitivity of S-ICTP as a bone resorptive marker is thus questioned. In conclusion, a dose-dependent increase in markers of growth hormone metabolism and in biochemical markers of both bone and non-bone collagen synthesis was seen following incremental doses of GH in GHD.

Adult↗
PubMed1996

Beer potomania: two cases and review of the literature.

The association of severe hyponatremia and the ingestion of large quantities of beer, termed beer potomania, has been known for several years. We report two new cases, and review 20 others from the medical literature. These patients usually have a history of binge beer drinking, poor dietary intake, and then present with severe hyponatremia and various mental status changes or seizures. Typical laboratory findings include hyponatremia, hypokalemia, and a very dilute urine. The patients respond quickly to the administration of sodium chloride containing i.v. fluids. We propose that the pivotal pathophysiologic mechanism in beer potomania syndrome is the minimal intake of solute and the hypoosmolality of the beer ingested. This will lead to the inability to excrete sufficient amounts of free water to keep up with the ingestion of large quantities of the hyposmolar beer. Treatment with isotonic sodium chloride results in the rapid clearance of the accumulated excess free water.

Alcohol Drinking↗
PubMed1996

Quality of life in long-term survivors of marrow transplantation: comparison with a matched group receiving maintenance chemotherapy.

A retrospective descriptive study was designed to assess the quality of life (QoL) and psychosocial adjustment in long-term BMT survivors compared with a group of patients with haematological malignancies receiving maintenance chemotherapy (MC), matched for age, post-treatment time, sociodemographic and disease characteristics. The sample consisted of 91 long-term BMT survivors and 73 MC patients from three teaching hospitals in the UK. The results indicated that most of the BMT subjects had a good to excellent quality of life and, in some domains, even better adjustment than the MC patients. However, 20% of the BMT subjects had failed to return to full-time employment at a mean post-BMT time of almost 40 months. A significant number of BMT subjects were also identified with symptoms of anxiety and depression. The physical symptomatology had an association with psychological status. Impotence-related difficulties, decreased sexual satisfaction and altered body image were the main characteristics of psychosexual dysfunction in the BMT group. Poorer quality of life was predicted by the presence of depressive symptoms, low affirmation, and impoverished social adjustment.

Adolescent↗
PubMed1996

The Cardiac Arrhythmia Suppression Trial: Implications for nursing practice.

BACKGROUND: Care of patients with ventricular arrhythmia after myocardial infarction requires careful nursing management, including assisting with arrhythmia monitoring and testing. Because ventricular premature depolarization is a known risk factor for sudden cardiac death, it was hypothesized that the suppression of asymptomatic or mildly symptomatic ventricular premature depolarization would improve survival in these patients. OBJECTIVE: To review the Cardiac Arrhythmia Suppression Trial findings and provide implications for nursing practice for patients after myocardial infarction. METHODS: The Cardiac Arrhythmia Suppression Trial was a multicenter, randomized, placebo-controlled trial designed to determine whether the suppression of ventricular premature depolarizations in postmyocardial infarction patients would improve survival. Three class I antiarrhythmic drugs were used: encainide, flecainide, or moricizine. Patients for whom the drug suppressed their arrhythmia 80% or more were randomly assigned to that drug and dose or its matching placebo and were followed every 4 months (main study). Patients with 1% to 79% suppression were randomly assigned to the drug or its placebo that best treated their arrhythmia and followed every 4 months. RESULTS: Suppression of asymptomatic or mildly symptomatic ventricular premature depolarization in patients using encainide, flecainide, or moricizine failed to improve patient survival and was even harmful in some cases. CONCLUSIONS: Our results showed that in the absence of effective antiarrhythmic drug therapy, supportive nursing care and arrhythmia monitoring is important until appropriate therapy for the management of these arrhythmias in patients who have had a myocardial infarction can be found. Clinical trials are essential to provide an evaluation of therapies and direction for further studies, as well as a basis for practicing clinicians.

Aged↗
PubMed1996

False-negative endoscopic biopsy of colonic adenocarcinoma in a young man.

A 26-year-old man presented with intermittent bright red blood per rectum. His physical examination was unremarkable; however, because microcytic anemia was noted, the patient underwent colonoscopy. A large ascending colonic lesion was noted, a biopsy of which was negative for cancer. Nevertheless, the patient underwent a radical hemicolectomy. Adenocarcinoma of the cecum was found. This case report is an example of a false-negative endoscopic-directed biopsy. A review of recorded video-endoscopy assisted the family physician in appropriate management.

Adenocarcinoma↗
PubMed1996

Decrease in the size of ovarian endometriomas during ovarian suppression in stage IV endometriosis. Role of preoperative medical treatment.

OBJECTIVE: To evaluate the effect of hormonal suppression on the size of ovarian endometriomas and to develop a predictive model for changes in the size of these lesions. STUDY DESIGN: The study consisted of 80 women of reproductive age with the diagnosis of stage IV pelvic endometriosis, according to the revised American Fertility Society (rAFS) classification, and included 48 women with endometriomas > or = 3 cm. After the initial laparoscopic and sonographic evaluation, ovarian suppression was achieved with either danazol or a gonadotropin-releasing hormone agonist (GnRH-a) for six months. In all patients, pretreatment and posttreatment pelvic sonograms were performed, and at the end of treatment residual disease was evaluated and resected by laparotomy or laparoscopy. Seven of 80 women with endometriomas > or = 3 cm had serial sonograms during the course of therapy. Serial pelvic sonograms in this subgroup were used to develop a statistical model for predicting the size of endometriomas after treatment. The model was then tested in another subgroup of 41 women with endometriomas > or = 3 cm. RESULTS: At the end of treatment, there was a significant decrease in the r-AFS score in both the danazol and GnRH-a groups. Medical treatment facilitated surgical resection of residual disease and preservation of ovarian tissue. There was no difference in this respect between danazol and GnRH-a. Endometriomas decreased by 51% in both treatment groups. The predictive model, when tested on 41 patients, underestimated the actual change by 11%, but the difference was within the 95% confidence limits. CONCLUSION: This study documented, for the first time, that ovarian endometriomas decrease in size during hormonal suppression. Both danazol and GnRH-a were equally effective.

Adult↗
PubMed1996

NESTROFT as a screening test for the detection of thalassaemia & common haemoglobinopathies--an evaluation against a high performance liquid chromatographic method.

The NESTROFT method (Naked Eye Single Tube Red Cell Osmotic Fragility Test) was evaluated against a high performance liquid chromatographic (HPLC) method for its usefulness in screening for beta-thalassaemia and some of the common haemoglobinopathies. Blood samples (137) from patients with suspected haemoglobin disorders were analyzed by both methods. Among the 63 patients with heterozygous beta-thalassaemia on HPLC, NESTROFT was positive for 49, 'doubtful' for 13 and negative for 1. Of the 32 patients with other haemoglobin disorders, 28 were positive on NESTROFT and 4 were 'doubtful'. Of the 42 'normal' samples, NESTROFT was positive for 6, 'doubtful' for 8 and negative for 28. This test showed an overall sensitivity of 98.7 per cent, specificity of 66.6 per cent, positive predictive value of 87 per cent and negative predictive value of 96.5 per cent. We conclude that, NESTROFT is a suitable test for screening for beta-thalassaemia and the common haemoglobinopathies seen in India. It is easy to perform, simple, inexpensive and does not require sophisticated equipment. Subjects who are NESTROFT 'positive' or 'doubtful' deserve further investigation.

Chromatography, High Pressure Liquid↗
PubMed1996

Use of endometrial measurement as an exclusion criterion for in vitro fertilization using clomiphene citrate.

OBJECTIVE: Previous reports have indicated an association between endometrial development and pregnancy outcome for patients treated with clomiphene citrate (CC) in conjunction with intrauterine insemination or intercourse. We expanded the use of CC for ovulation induction in association with in vitro fertilization (IVF). This study was designed to determine if endometrial thickness should be used as an inclusion or exclusion criterion for CC-IVF. STUDY DESIGN: One hundred twenty-eight patients were enrolled in an ovulation-induction regimen using CC for expected IVF-ET between January 1992 and December 1992. A total of 81 patients met inclusion criteria for CC-IVF and had endometrial measurement performed prior to human chorionic gonadotropin administration. Patients were categorized on the basis of endometrial measurement as follows: (A) > 4 - < 7 mm, (B) > or = 7 - < or = 10 mm, and (C) > 10 mm. Standard IVF was performed, and pregnancy rates for each category were evaluated. RESULTS: A total of 23 pregnancies (28% per retrieval) were established. Pregnancy rates were not different by category (P > .10, Fisher's Exact Test): (A) 3/15 (20%), (B) 13/41 (32%), and (C) 7/25 (28%). CONCLUSION: These data suggest that for CC-IVF. endometrial measurement should not be used as an exclusion criterion since pregnancies occurred at comparable frequencies in all the groups.

Adult↗
PubMed1996

[Qualitative versus quantitative research methods: paradigmatic alternatives--an issue in nursing?].

This discussion of alternative methodologies arises from research conducted in 1994 about the development and determinants of satisfaction in basic nursing education. In this project qualitative approaches were used to allow a comparison of the results with those achieved by standardised quantitative investigations. Besides the fact that satisfaction in basic nursing education has so far been investigated predominantly with quantitative methods which limit the responses of the subjects from the outset, critics in the field of occupational research have pointed to the necessity of using qualitative methods in investigating job satisfaction. Following a historical review of the methodological debate in the social sciences, a presentation of fundamental aspects and criteria of quantitative and qualitative methods and a detailed description of the research strategy used in the above project, a comparison of the results will attempt to answer the research question.

Education, Nursing, Baccalaureate↗
PubMed1995

Neuregulin receptors, erbB3 and erbB4, are localized at neuromuscular synapses.

Neuregulin (NRG) is concentrated at synaptic sites and stimulates expression of acetylcholine receptor (AChR) genes in muscle cells grown in cell culture. These results raise the possibility that NRG is a synaptic signal that activates AChR gene expression in synaptic nuclei. Stimulation of NRG receptors, erbB3 and erbB4 initiates oligomerization between these receptors or between these receptors and other members of the epidermal growth factor (EGF) receptor family, resulting in stimulation of their associated tyrosine kinase activities. To determine which erbBs might mediate synapse-specific gene expression, we used antibodies against each erbB to study their expression in rodent skeletal muscle by immunohistochemistry. We show that erbB2, erbB3 and erbB4 are concentrated at synaptic sites in adult skeletal muscle. ErbB3 and erbB4 remain concentrated at synaptic sites following denervation, indicating that erbB3 and erbB4 are expressed in the postsynaptic membrane. In addition, we show that expression of NRG and erbBs, like AChR gene expression, increases at synaptic sites during postnatal development. The localization of erbB3 and erbB4 at synaptic sites is consistent with the idea that a NRG-stimulated signaling pathway is important for synapse-specific gene expression.

Animals↗