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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   
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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   
4.
Purpose To describe our preliminary experience with the addition of a GnRH antagonist (Nal-Glu) and exogenous gonadotropins (follicle stimulating hormone; FSH) to unstimulated IVF cycles.Method Seven spontaneously ovulatory women underwent eight unstimulated IVF cycles at our institution. They were treated with a single dose of Nal-Glu, 50 g/ kg, or with a combination of Nal-Glu, 50 g/kg, and exogenous FSH, 150–300 IU, during the late follicular phase of spontaneous cycles. They then received 10,000 IU of human chorionic gonadotropin (hCG) to time accurately follicle aspiration in unstimulated IVF cycles.Results Two women underwent three cycles with Nal-Glu alone on the day of hCG administration. One pregnancy resulted. Five women underwent five cycles with 3 to 6 days of daily Nal-Glu and FSH. Four of these cycles resulted in aspiration after the FSH dose was increased to 300 IU. Nal-Glu and FSH allowed continued development of the dominant follicle without the occurrence of luteinizing hormone (LH) surge.Conclusions (1) Nal-Glu alone given 18 hr prior to hCG did not interfere with continued follicle viability or with the attainment of pregnancy. (2) Simultaneous Nal-Glu and FSH allowed for continued growth and development of the dominant follicle without the occurrence of an LH surge. (3) This preliminary experience confirms the feasibility of this novel approach, which may ultimately enhance the efficacy of unstimulated IVF cycles by eliminating premature ovulation and maximizing control of gonadotropin delivery to the developing follicle.Presented at the 39th Meeting of The Society for Gynecologic Investigation, San Antonio, Texas, March 18–21, 1992.  相似文献   
5.
PURPOSE: We compared the efficacy of combination chemotherapy versus single-agent therapy in patients with advanced non-small-cell lung cancer. PATIENTS AND METHODS: A total of 561 eligible patients were randomly assigned to receive paclitaxel alone or in combination with carboplatin. RESULTS: The response rate was 17% in the paclitaxel arm and 30% in the carboplatin-paclitaxel arm (P < .0001). Median failure-free survival was 2.5 months in the paclitaxel arm and 4.6 months in the carboplatin-paclitaxel arm (P = .0002). Median survival times were 6.7 months (95% CI, 5.8 to 7.8) and 8.8 months (95% CI, 8.0 to 9.9), and 1-year survival rates were 32% (95% CI, 27% to 38%), and 37% (95% CI, 32% to 43%), respectively. The overall survival distributions were not statistically different: hazard ratio = 0.91 (95% CI, 0.77 to 1.17; P = .25). Hematological toxicity and nausea were more frequent in the combination arm, but febrile neutropenia and toxic deaths were equally low in both arms. There was no significant survival difference in elderly patients. Performance status 2 patients treated with combination chemotherapy had a better survival rate than those treated with single-agent therapy (P = .019). CONCLUSION: Combination chemotherapy improves response rate and failure-free survival compared with single-agent therapy, but there was no statistically significant difference in the primary end point of overall survival. The results in elderly patients were similar to younger patients. Performance status 2 patients had a superior outcome when treated with combination chemotherapy.  相似文献   
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Articular ultrasound of 6500 joint recesses was performed for the purpose of identifying which joint had the highest measurements among small-sized (SSJ), medium-sized (MSJ) and large-sized (LSJ) joints. Quantitative measurements of synovial hypertrophy (QSR) and semiquantitative measurements of synovial hypertrophy (SSH), power Doppler (SPD) and bone erosion (SBE) (score: 0–3) were made. Higher measurements (p < 0.01) of QSR were obtained in the second metatarsophalangeal joint (MTP), talonavicular joint, and hip. The highest SSH scores (2/3) were obtained in the second MTP, talonavicular joint, hip and knee; the highest SPD scores (1/2/3) in the first MTP, second MTP, dorsal second metacarpophalangeal (MCP) and radiocarpal recesses; and the highest SBE scores (2/3) in the radiocarpal, ulnocarpal and posterior recesses of the glenohumeral joint. In conclusion, higher measurements of synovial hypertrophy were found in the first and second MTPs (SSJ), talonavicular recess (MSJ) and hip (LSJ). Synovial blood flow was frequent in the first MTP and radiocarpal recess. Bone erosion stood out only in the glenohumeral joint.  相似文献   
8.

Background

The right ventricular ejection fraction (RVEF) is a surrogate marker of right ventricular function in pulmonary hypertension (PH), but its measurement is complicated and time consuming. The tricuspid annular plane systolic excursion (TAPSE) measures only the longitudinal component of RV contraction while the right ventricular fractional area change (RVFAC) takes into account both the longitudinal and the transversal components. The aim of our study was to evaluate the relationship between RVEF, RVFAC, and TAPSE according to hemodynamic severity in two groups of patients with PH: pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH).

Methods and Results

Fifty-four patients with PAH (n?=?15) and CTEPH (n?=?39) underwent right heart catheterization and cardiac magnetic resonance (CMR). The ventricular volumes and areas, TAPSE, and eccentricity index were measured. The RVFAC was more strongly correlated with the RVEF (r?=?0.81, p?<?0.0001) than the TAPSE (r?=?0.63, p?<?0.0001). RVEF?<?35% was better predicted by the RVFAC than the TAPSE (TAPSE: AUC?=?0.77 and RVFAC: AUC?=?0.91; p?=?0.042). In the group with the worse hemodynamic status, the RVFAC correlated much better with the RVEF than the TAPSE. There were no significant differences in the CMR data analyzed between the groups of PAH and CETPH patients.

Conclusions

The RVFAC is a good index to estimate RVEF in PH patients; even better than the TAPSE in patients with more severe hemodynamic profile, possibly for including the transversal component of right ventricular function in its measurement. Furthermore, RVFAC performance was similar in the two PH groups (PAH and CTEPH).
  相似文献   
9.
GeroScience - Aging of the vasculature is characterized by endothelial dysfunction and arterial stiffening, two key events in the pathogenesis of cardiovascular disease (CVD). Treatment with sodium...  相似文献   
10.
BackgroundStrength training has beneficial effects on kidney disease, in addition to helping improve antioxidant defenses in healthy animals.ObjectiveTo verify if strength training reduces oxidative damage to the heart and contralateral kidney caused by the renovascular hypertension induction surgery, as well as to evaluate alterations in the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) endogenous antioxidant enzymes.MethodsEighteen male rats were divided into three groups (n=6/group): sham, hypertensive, and trained hypertensive. The animals were induced to renovascular hypertension through left renal artery ligation. Strength training was initiated four weeks after the induction of renovascular hypertension, continued for a 12-weeks period, and was performed at 70% of 1RM. After the training period, the animals were euthanized and the right kidney and heart were removed for quantitation of hydroperoxides, malondialdehyde and sulfhydryl groups, which are markers of oxidative damage. In addition, the activity of SOD, CAT, and GPx antioxidant enzymes was also measured. The adopted significance level was 5% (p < 0.05).ResultsAfter strength training, a reduction in oxidative damage to lipids and proteins was observed, as could be seen by reducing hydroperoxides and total sulfhydryl levels, respectively. Furthermore, an increased activity of superoxide dismutase, catalase, and glutathione peroxidase antioxidant enzymes was observed.ConclusionStrength training is able to potentially reduce oxidative damage by increasing the activity of antioxidant enzymes. (Arq Bras Cardiol. 2021; 116(1):4-11)  相似文献   
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