Search PubMed⌕ Search

Biomedical subjects

D Sim

Publications and source records attributed to D Sim.

12 recordsLinked to original sources

Adrenal suppression from high-dose inhaled fluticasone propionate in children with asthma.

This cross-sectional study was designed to examine the prevalence of adrenocortical suppression in children with asthma treated with high-dose inhaled fluticasone propionate (FP). Children and adolescents (n=50) with asthma, treated with inhaled FP at a dose of > or = 1,000 mg a day for > or = 6 months, were enrolled. Early morning serum cortisol was performed. Subjects with a serum cortisol of < 400 nmol x L(-1) had a tetracosactrin stimulation test. Fifty subjects of mean age 13.1 yrs were treated with a mean dose of 924.7 microg x m(-2) x day(-1) FP for a mean duration of 2 yrs. Of the 50 subjects, 36 (72%) had serum cortisol levels of < 400 nmol x L(-1) and underwent tetracosactrin stimulation test. Of these, 6 (17%) demonstrated a less than two-fold increase in serum cortisol from baseline and peak cortisol level of < or = 550 nmol x L(-1) at 30 or 60 min poststimulation. There was a significant negative correlation between the dose of FP x m(-2) and stimulated peak cortisol level. Biochemical evidence of adrenocortical insufficiency was demonstrated in 12% of the subjects, indicating that high-dose fluticasone propionate use may be associated with dose-dependent adrenocortical suppression.

Administration, Inhalation↗

Possible protective role of HLA-B*2706 for ankylosing spondylitis.

HLA-B27 is strongly associated with ankylosing spondylitis (AS) but the role of the HLA molecule itself is still unclear. In this study on Singapore Chinese, we have subtyped 50 B27 positive AS patients and 45 B27 positive normals and found that the B*2706 allele has a significant negative association with disease (p = 0.047). Together with recent data indicating the existence of AS "protective" B27 alleles, our data shows that the HLA molecule itself plays a crucial role in disease development.

Alleles↗

Lipids and lipoproteins during antihypertensive drug therapy. Comparison of doxazosin and atenolol in a randomized, double-blind trial: the Alpha Beta Canada Study.

A randomized double-blind trial comparing the alpha-adrenergic blocker doxazosin and the beta-adrenergic blocker atenolol was completed by 131 patients with mild to moderate hypertension. Blood pressure and fasting blood lipids were determined at baseline and 4, 12, and 24 weeks of treatment. At entry, plasma lipids and lipoproteins were similar in those patients randomized to doxazosin or atenolol. After 24 weeks of treatment with atenolol, there were significant (P < .05) decreases in high-density lipoprotein cholesterol (HDL-C) and increases in triglycerides and very-low-density triglycerides (VLDL-T). In contrast, doxazosin was associated with significant (P < .05) increases in HDL-C and decreases in triglycerides and VLDL-T. There were no significant differences in HDL apolipoprotein (apo) A-I or low-density lipoprotein apoB between the drugs, but atenolol decreased the ratio of HDL-C to apoA-I, and doxazosin increased this ratio, differences that were statistically significant (P < .002). Neither apoA-I nor apoB concentration at baseline nor apoE phenotype was predictive of the lipid responses during antihypertensive treatment with either drug. Thus, there are significant favorable changes in HDL-C, total triglycerides, and VLDL-T between patients with mild to moderate hypertension and normal plasma lipids when treated with the alpha-blocker doxazosin compared with the beta-blocker atenolol. Plasma lipid or apo concentrations were not predictive of their lipid response during antihypertensive therapy with either of these agents.

Apolipoproteins E↗

Comparative trial of doxazosin and atenolol on cardiovascular risk reduction in systemic hypertension. The Alpha Beta Canada Trial Group.

The impact of treating hypertension on coronary artery disease has been less than anticipated from epidemiologic studies of cardiovascular risk factors. It has been suggested that adverse effects on lipids of traditional diuretic or beta-blocker regimens may diminish the potential benefits of antihypertensive therapy. Patients with mild to moderate systemic hypertension and normal serum lipids (n = 191) were randomly assigned to doxazosin or atenolol. After dose titration to goal diastolic blood pressure of < or = 90 mm Hg, patients continued treatment for a further 24 weeks. The principal outcome measurement was overall coronary artery disease risk using the Framingham formula. Relative risk of coronary artery disease was reduced to 92.4% of baseline (p = 0.144) for evaluable patients taking atenolol (n = 71), and to 74.6% (p = 0.0001) for patients taking doxazosin (n = 51): atenolol versus doxazosin, p = 0.0074. In patients who met the strict Framingham criteria for age, total cholesterol and high density lipoprotein cholesterol, the relative risk of coronary artery disease for patients taking atenolol (n = 23) was reduced to 86.2% of baseline (p = 0.082), and to 67.4% (p = 0.0004) for patients taking doxazosin (n = 18): atenolol versus doxazosin, p = 0.049. Alpha blockade with doxazosin was more effective than beta blockade with atenolol in reducing the risk of coronary artery disease in hypertensive patients because of the beneficial effects of doxazosin on high-density lipoprotein cholesterol. Overall withdrawal rate was greater in the alpha-blocker group because of a lower response rate and more adverse events.

Adult↗

Evaluation of biophysical fetal assessment in high-risk pregnancy to assess ultrasound parameters suitable for screening in the low-risk population.

During a 1-year period, 662 pregnant women at 24-43 weeks' gestation were referred to the Department of Obstetrics and Gynaecology, at the Queens University Belfast, for fetal assessment because they were clinically suspected to be at high risk of perinatal complications. The results of our investigations were made available to the referring obstetricians who undertook the further management of the pregnancies. Subsequently six pregnancies resulted in perinatal deaths and 97 (14.7%) in the delivery of small-for-gestational-age infants. We restrospectively analyzed the data from ultrasonographic evaluation of the fetus and subjective and objective assessments of the amniotic fluid volume to determine their value in the prediction of adverse perinatal outcome. A fetal abdominal circumference < 10th centile for gestation or a subjectively reduced amniotic fluid volume identified 87 (90%) of small-for-gestational-age infants and five of the six perinatal deaths. When comparing the abdominal circumference and subjective liquor volume, both were sensitive in predicting delivery of a small-for-gestational-age fetus (sensitivity 86% vs. 53%, respectively) and perinatal death (sensitivity 50% vs. 83%, respectively). We suggest that, since assessments of these two factors are complementary in evaluating a high-risk pregnancy and can be measured in under 5 min, they now warrant consideration for screening in a prospective randomized trial in an unselected low-risk population.

Journal Article↗

Early amniocentesis: experience of 222 consecutive patients, 1987-1988.

Early amniocentesis from 9 to 14 weeks' gestation provides a safe and accurate method of prenatal diagnosis of cytogenetic and biochemical disorders. There was a 100 per cent success rate in culturing the amniotic cells from 222 samples obtained between 9 and 14 weeks' gestation. Follow-up of the patients to delivery revealed an abortion rate of 1.4 per cent. Among the 207 live- and stillborn infants, only one had a congenital abnormality (bilateral talipes equino-varus) and no infant had respiratory distress syndrome or pneumonia. Eleven pregnancies were terminated following the detection of a chromosomal, biochemical, or congenital abnormality (5.0 per cent). However, before the procedure of early amniocentesis becomes routine clinical practice, it requires appraisal by a randomized clinical trial.

Amniocentesis↗

Interstitial parametrial implants in carcinoma of the cervix stage II-B.

This retrospective analysis has been undertaken to ascertain whether an improvement in results can be obtained in Stage II-B cervical carcinoma with the use of interstitial parametrial irradiation. Between September 1972 and March 1982, 43 patients were treated by conventional intracavitary irradiation. Nine patients at high risk for local recurrence underwent post-radiation hysterectomy. Since 1980, 45 patients were entered into a study using parametrial interstitial implants and no hysterectomy. Patients were not allocated randomly and the interstitial group contained a disproportionate number of patients with poor prognostic features. Mean follow-up for the conventional radiotherapy group was 80 months, and for the interstitial group was 42 months. Overall pelvic control and actuarial survival in the conventional radiotherapy group (84 and 75%, respectively) were similar (log rank p-value = .61) to that observed in the interstitial implant group (80 and 77%). Analysis of pelvic control rates showed no significant advantage for either treatment group when compared by the various prognostic factors. The frequency of complications, however, was significantly higher in the interstitially irradiated patients (21% vs. 7%, p = .044).

Adenocarcinoma↗

The effect of rate of heating or cooling prior to heating on tumor and normal tissue microcirculatory blood flow.

Single vessel responses to hyperthermia were studied in tumor and normal tissues using a transparent access window chamber. Rates of heating less than or equal to .68 degrees C/minute preserved relatively better vascular function in normal than tumor tissue. A rate of heating of 1.0 degrees C/minute lowered normal tissue statis temperatures so they were no different from tumor. Cooling to 30 degrees C prior to heating slowed normal arteriolar flows to less than 5% of 38 degrees C controls. Heating resulted in increased flow in those vessels, but maximum flows never exceeded 5% of flows achieved in similar vessels which were not cooled first. The implications of this work are that rate of heating and cooling prior to heating can alter normal tissue vascular response to heat in a way that could prove deleterious to maintaining efficient vascular function in that tissue relative to tumor.

Adenocarcinoma↗

Survival of colorectal cancer patients in relation to duration of symptoms and other prognostic factors.

The effect of duration of symptoms and other prognostic factors on survival was studied by interview using a population-based sample of 154 colorectal cancer patients. The authors found that symptom durations of up to approximately one year before diagnosis had no effect on survival. In addition, it was found that the total number of symptoms was a statistically significant predictor of survival, although no single symptom had a significant effect. Stage, sex, and site also were found to be significant predictors of survival, whereas age, socioeconomic status, and other factors were not predictive.

Age Factors↗