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51.
Purpose The purpose of the present study was to evaluate the effect of angiotensin II and its inhibitor, saralasin, on steroid production by luteinized human granulosa cells in vitro. Granulosa cells were obtained from follicular fluid aspirations from human in vitro fertilization. Cultures were established in supplemented Ham's F-10 medium. Human chorionic gonadotropin and angiotensin II were added to culture media and the effect on steroid production was measured. Results Human chorionic gonadotropin alone stimulated production of progesterone, estradiol, and testosterone. The addition of angiotensin II resulted in a dose-dependent increase in progesterone production (428% increase compared to baseline). No effect was seen on estradiol or testosterone. However, a large increase (700%) in estradiol was seen with the addition of the competitive inhibitor of angiotensin II, saralasin. Conclusion We conclude that angiotensin II modulates progesterone production by human luteinized granulosa cells in vitro. The observed enhancement of estradiol production by angiotensin blockade suggests a tonic inhibition of estradiol secretion by endogenous angiotensin II. Presented at the 36th Annual Meeting Society for Gynecologic Investigation, March, 1989, San Diego, California.  相似文献   
52.
OBJECTIVE: To investigate the molecular epidemiology of systemic nosocomial infections caused by Enterobacter cloacae. SETTING: Neonatal intensive care unit (NICU) of a tertiary-care university hospital. PATIENTS: Forty-two high-risk neonates with systemic infections caused by E. cloacae. METHODS: From 1995 to 1997, the variables associated with death in these patients were evaluated. The molecular epidemiology of the strains responsible for the systemic infections, and 14 unrelated strains, was studied using plasmid analysis and pulsed-field gel electrophoresis (PFGE). RESULTS: The overall mortality rate for infection caused by E. cloacae was 34%, whereas the crude mortality rate during the study period was 8.12% (P < .001). Gestational age (preterm neonates) and birth weight (small for gestational age) were not associated with a higher risk of death. Insertion of a venous catheter by dissection of a peripheral vein was the only invasive procedure related to death (P = .016) in this study. A molecular analysis showed that three outbreaks, each occurring in a different year, were caused by strains with distinctive DNA profiles. Only one outbreak was identified by the infection control service, in the NICU. Plasmid analysis and PFGE showed similar ability to discriminate control strains from the E. cloacae strains isolated from the neonates. CONCLUSIONS: Systemic infections caused by E. cloacae in our NICU were associated with a high mortality rate and occurred as small, unrecognized outbreaks. These results may not be generalizable because the data were from a single center.  相似文献   
53.

OBJECTIVE:

To study the effects of mycophenolate sodium on mucociliary clearance.

INTRODUCTION:

Mycophenolate is one of the most commonly used immunosuppressive drugs in lung transplantation. Although its pharmacokinetic properties are well defined, its side effects on mucociliary clearance have not yet been studied.

METHODS:

Sixty rats were subjected to left bronchial section and anastomosis. The right bronchus was used as a control. After surgery, the rats were assigned to two groups based on whether they received saline solution (n = 30) or mycophenolate sodium (n = 30). After 7, 15, or 30 days of treatment, 10 animals from each group were sacrificed, and in vitro mucus transportability, in situ mucociliary transport velocity and ciliary beat frequency were measured.

RESULTS:

The analysis of mucus transportability revealed that neither mycophenolate nor bronchial section altered any transportability related property for up to 30 days of treatment after surgery (p>0.05). With regard to ciliary beat frequency, the operated left bronchi from the mycophenolate group showed a significant decrease on post-surgical day 30 (p = 0.003). In addition, we found a significant reduction in the in situ mucociliary transport velocity in the mycophenolate-treated group (p = 0.0001).

DISCUSSION:

These data add important information regarding mucociliary clearance dysfunction following mycophenolate therapy and suggest that mycophenolate might contribute to the high incidence of respiratory tract infections in lung transplant patients. Further studies are needed to investigate the combined action of mycophenolate with other immunosuppressive drugs and to establish methods to protect and recover mucociliary clearance, an important airway defense mechanism.  相似文献   
54.
OBJECTIVE: To determine if 17beta-estradiol increases blood pressure in postmenopausal women. DESIGN: A total of 222 healthy postmenopausal women were randomly assigned to either 1 mg micronized 17beta-estradiol daily or placebo for 2 years. Blood pressure measurements were obtained every other month and common carotid artery intima-media thickness measured every 6 months. Statistical analyses comparing longitudinal changes in systolic and diastolic blood pressure between treatment groups used a mixed general linear model including interaction terms to evaluate variations by age or estradiol level. RESULTS: Both placebo and estradiol groups showed small declines in systolic and diastolic blood pressure during the trial among the normotensive subjects and subjects on antihypertensive medications. However, the decline did not differ significantly between the groups. Treatment effects on systolic blood pressure differed significantly by the age of the subject (interaction P value = 0.04) with younger women on estradiol showing on average a rise in systolic blood pressure, and older women a decline. The association between serum estradiol level and systolic blood pressure showed a similar modification with age (P = 0.03). Changes in systolic blood pressure in women on estradiol were positively correlated with intima-media thickness progression (P = 0.03). CONCLUSIONS: Overall, 17beta-estradiol did not influence changes in blood pressure in normotensive or hypertensive women. The effect of 17beta-estradiol treatment on systolic blood pressure may be influenced by a woman's age. Estradiol may increase systolic blood pressure in younger postmenopausal women, while having the opposite effect in older postmenopausal women.  相似文献   
55.
Observational studies suggest that postmenopausal hormone therapy (HT) prevents coronary heart disease, whereas randomized clinical trials have not confirmed a cardioprotective effect. Although observational studies may have overestimated the coronary benefit conferred by postmenopausal hormone use, there are other plausible explanations for the apparent discrepancy between previous results and the less favorable findings from clinical trials such as the large Women's Health Initiative. There is now a critical mass of data to support the hypothesis that age or time since menopause may importantly influence the benefit-risk ratio associated with HT, especially with respect to cardiovascular outcomes, and that the method of administration, dose, and formulation of exogenous hormones may also be relevant. Although the weight of the evidence indicates that older women and those with subclinical or overt coronary heart disease should not take HT, estrogen remains the most effective treatment currently available for vasomotor symptoms, and its effects on the development of coronary disease in newly postmenopausal women remain unclear. Moreover, effects of HT on quality of life and cognitive function in recently postmenopausal women merit further study. These unresolved clinical issues provide the rationale for the design of the Kronos Early Estrogen Prevention Study, a 5-year randomized trial that will evaluate the effectiveness of low-dose oral estrogen and transdermal estradiol in preventing progression of atherosclerosis in recently postmenopausal women.  相似文献   
56.

Study Objective:

To evaluate if a portable monitor could accurately measure the apnea-hypopnea index (AHI) in patients with a suspicion of obstructive sleep apnea (OSA).

Design:

Prospective and randomized.

Setting:

Sleep laboratory.

Participants:

80 participants: 70 patients with clinical OSA suspicion and 10 subjects without suspicion of OSA.

Interventions:

N/A

Measurements and Results:

Three-order randomized evaluations were performed: (1) STD (Stardust II) used at the participants'' home (STD home), (2) STD used simultaneously with PSG in the sleep lab (STD+PSG lab), and (3) PSG performed without the STD (PSG lab). Four AHI values were generated and analyzed: (a) STD home; (b) STD from STD+PSG lab; (c) PSG from STD+PSG (named PSG+STD lab); and (d) PSG lab. Two technicians, blinded to study details, performed the analyses of all evaluations. There was a strong correlation between AHI from the STD and PSG recordings for all 4 AHI values (all correlations above 0.87). Sensitivity, specificity, and positive and negative predictive values at AHI cut-off values of 5, 15, and 30 events/hour were calculated. AHI values from the PSG lab and PSG+STD lab were compared to STD home and STD+PSG lab and showed the best results when STD and PSG were performed simultaneously. In all analyses, the area under ROC curve was at least 0.90. With multiple comparisons, diagnostic agreement was between 91% and 75%. The Bland Altman analyses showed strong agreement between AHI values from the STD and PSG recordings, especially when comparing the AHI from simultaneous STD and PSG recordings.

Conclusion:

These data suggest that the STD is accurate in confirming the diagnosis of OSA where there is a suspicion of the disorder. Better agreement occurred during simultaneous recordings.

Citation:

Santos-Silva R; Sartori DE; Truksinas V; Truksinas E; Alonso FFFD; TufikS; Bittencourt LRA. Validation of a portable monitoring system for the diagnosis of obstructive sleep apnea syndrome. SLEEP 2009;32(5):629-639.  相似文献   
57.

Objective

This study sought to define the role of first-line platinum-based doublet chemotherapy in older patients with non-small cell lung cancer (NSCLC).

Materials and Methods

We analyzed three first-line NSCLC trials: CALGB 9730, CALGB 30203, and CALGB 30801, which tested carboplatin and paclitaxel; carboplatin and gemcitabine; and carboplatin with either pemetrexed or gemcitabine, respectively. Overall survival was the primary endpoint. Age-based comparisons with a cutpoint of 65?years were performed with Cox proportional hazards models with adjustments for sex, tumor histology, cancer stage, chemotherapy, and smoking history and after stratifying by performance score. Secondary endpoints were grade 3–5 adverse events, chemotherapy cycles completed, and whether toxicity prompted chemotherapy discontinuation.

Results

730 patients were included; 337 (46%) were 65+ years of age. No statistically significant difference in survival was observed for older (≥65) versus younger patients (HR?=?1.096; 95% CI?=?(0.94, 1.28); p?=?0.25). A trend emerged with increased odds of a grade 3–5 adverse event for patients ≥65?years versus <65?years (OR?=?1.52; 95% CI?=?(0.99, 2.31); p?=?0.05). The proportion of completed chemotherapy cycles was marginally lower in older patients (difference?=??5%; 95% CI?=?(?9, 0.2); p?=?0.06) for those ≥65?years versus <65?years, but no statistically significant difference occurred in the rate of chemotherapy discontinuation for toxicity (OR?=?1.4; 95% CI?=?(0.85, 2.19); p?=?0.21) for patients ≥65?years versus <65?years. A cutpoint of 70?years yielded similar results.

Conclusion

These findings support carboplatin doublet-based chemotherapy in select older patients with advanced NSCLC.  相似文献   
58.
OBJECTIVE: To investigate the efficacy of soy isoflavone on climacteric symptoms in postmenopausal women. DESIGN: In this double-blind, randomized, placebo-controlled study, a total of 80 women (mean age = 55.1 years), who reported 5 or more hot flush episodes per day, were randomized to receive either 250 mg of standardized soy extract (Glycine max AT) a total of 100mg/day of isoflavone (n = 40) or placebo (n = 40). Exclusion criteria included: contra-indication for hormone therapy (HT), chronic gastrointestinal diseases, and users of HT within the preceding 6-months. For 10-months, climacteric symptoms were evaluated using a score card and the menopausal Kupperman index. Compliance and safety were also assessed. At baseline and the end of the study, lipid and hormonal profiles, as well as vaginal, mammographic and ultrasonographic parameters were measured. The t-test, Wilcoxon test and ANOVA were used in the statistical analysis. RESULTS: At baseline, the mean number of hot flushes was 9.6 +/- 3.9 per day in the isoflavone group and 10.1+/-4.9 in the placebo group (p>0.05). After 10 months, there was a significant reduction in frequency of hot flushes among isoflavone users when compared to those on placebo (3.1 +/- 2.3 and 5.9 +/- 4.3, respectively) (p<0.001). Kupperman index mean values showed a significant reduction in both groups. However, soy isoflavone was significantly superior to placebo, in reducing hot flush severity (69.9% and 33.7%, respectively) (p<0.001). Endometrial thickness, mammography, vaginal cytology, lipids and hormonal profile did not change in both groups. No serious adverse event related to isoflavone treatment was reported. CONCLUSIONS: The soy isoflavone extract exerted favorable effects on vasomotor symptoms and good compliance, providing a safe and effective alternative therapeutic for postmenopausal women.  相似文献   
59.
Evaluation of the Determine Rapid Syphilis TP assay using sera   总被引:1,自引:0,他引:1  
The Abbott Determine Rapid Syphilis TP assay is a treponemal test that can be used in resource-poor settings that lack laboratory facilities. However, this test has not been extensively evaluated. We measured its sensitivity and specificity by using stored serum specimens (n = 567) from all persons who tested Treponema pallidum hemagglutination assay (TPHA) positive (n = 250) or TPHA indeterminate (n = 17) in the year 2001 and the first 300 patients in 2001 who tested TPHA negative at the Evandro Chagas Research Institute in Rio de Janeiro, Brazil. This rapid assay was independently interpreted by three different observers. With TPHA results as the reference, sensitivity ranged between readers from 95.6 to 98.4% and specificity ranged from 97.3 to 95.7%. There was little interreader variability in the interpretation of results, with approximately 98% agreement for all reader combinations. Of samples from persons with human immunodeficiency virus (HIV) infection (n = 198), sensitivity was 96.9 to 99.2% and it was 94.4 to 96.3% among HIV-negative persons (n = 127). Specificity was 92.4 to 95.5% among HIV-positive persons and 97.2 to 100% among HIV-negative persons. We found this test to have high sensitivity and specificity and little interreader variability, indicating that it may be easily used in resource-poor settings without laboratory facilities. Further studies are needed using this test on whole blood and under the clinical conditions for which it is intended.  相似文献   
60.
Although rare, ALF caused by disseminated HSV infection is associated with high mortality in the neonatal population. This condition is often diagnosed relatively late due to the absence of specific signs. We present a case involving a neonate with ALF submitted to living donor liver transplantation without a prior diagnosis. The patient had no skin or mucosal lesions, and IgM serology was negative for HSV‐1 and HSV‐2. Immunohistochemical staining of the liver explant was positive for herpes virus infection, and the patient subsequently received antiviral drug treatment, with a good outcome. Due to organ shortages and the rarity of the aforementioned condition, LT has seldom been reported for the treatment of ALF caused by herpes virus infection; however, LT may be the only option for neonates with fulminant hepatitis. The use of living donors in an urgent scenario is well established in Eastern countries and safely applicable for pediatric patients with ALF.  相似文献   
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