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991.
Familial atrial fibrillation is a genetically heterogeneous disorder   总被引:14,自引:0,他引:14  
OBJECTIVES: The aims of this study were to identify and characterize familial cases of atrial fibrillation (AF) in our clinical practice and to determine whether AF is genetically heterogeneous. BACKGROUND: Atrial fibrillation is not generally regarded as a heritable disorder, yet a genetic locus for familial AF was previously mapped to chromosome 10. METHODS: Of 2,610 patients seen in our arrhythmia clinic during an 18-month study period, 914 (35%) were diagnosed with AF. Familial cases were identified by history and medical records review. Four multi-generation families with autosomal dominant AF (FAF 1 to 4) were tested for linkage to the chromosome 10 AF locus. RESULTS: Fifty probands (5% of all AF patients; 15% of lone AF patients) were identified with lone AF (age 41 +/- 9 years) and a positive family history (1 to 9 additional relatives affected). In FAF 1 to 3, AF was associated with rapid ventricular response. In contrast, AF in FAF-4 was associated with a slow ventricular response and, with progression of the disease, junctional rhythm and cardiomyopathy. Genotyping of FAF 1 to 4 with deoxyribonucleic acid markers spanning the chromosome 10q22-q24 region excluded linkage of AF to this locus. In FAF-4, linkage was also excluded to the chromosome 3p22-p25 and lamin A/C loci associated with familial AF, conduction system disease, and dilated cardiomyopathy. CONCLUSIONS: Familial AF is more common than previously recognized, highlighting the importance of genetics in disease pathogenesis. In four families with AF, we have excluded linkage to chromosome 10q22-q24, establishing that at least two disease genes are responsible for this disorder.  相似文献   
992.
Bronchiolar disorders   总被引:8,自引:0,他引:8  
Bronchiolar abnormalities are relatively common and occur in a variety of clinical settings. Various histopathologic patterns of bronchiolar injury have been described and have led to confusing nomenclature with redundant and overlapping terms. Some histopathologic patterns of bronchiolar disease may be relatively unique to a specific clinical context but others are nonspecific with respect to either etiology or pathogenesis. Herein, we present a scheme separating (1) those disorders in which the bronchiolar disease is the predominant abnormality (primary bronchiolar disorders) from (2) parenchymal disorders with prominent bronchiolar involvement and (3) bronchiolar involvement in large airway diseases. Primary bronchiolar disorders include constrictive bronchiolitis (obliterative bronchiolitis, bronchiolitis obliterans), acute bronchiolitis, diffuse panbronchiolitis, respiratory bronchiolitis, mineral dust airway disease, follicular bronchiolitis, and a few other rare variants. Prominent bronchiolar involvement may be seen in several interstitial lung diseases, including hypersensitivity pneumonitis, respiratory bronchiolitis-associated interstitial lung disease, cryptogenic organizing pneumonia (idiopathic bronchiolitis obliterans organizing pneumonia), and pulmonary Langerhans' cell histiocytosis. Large airway diseases that commonly involve bronchioles include bronchiectasis, asthma, and chronic obstructive pulmonary disease. The clinical relevance of a bronchiolar lesion is best determined by identifying the underlying histopathologic pattern and assessing the correlative clinico-physiologic-radiologic context.  相似文献   
993.
Much is known about the factors associated with risky sexual behavior among HIV-negative men who have sex with men (MSM) and among MSM whose HIV antibody status is unknown. However, little is known about the dynamics of continuing risky behavior among HIV-positive MSM. This research employed both questionnaire and extensive individual interview techniques to assess the levels of risky behavior, as well as the factors associated with risky behavior, in a sample of 42 seropositive MSM. Findings suggest that risky behavior occurs with some frequency, and that it is occasioned by informational, motivational, and behavioral skills-relevant deficits in the population at focus. Moreover, levels of risky behavior appear to differ with seropositive and seronegative primary partners. Implications for designing interventions for seropositive MSM are discussed.  相似文献   
994.
Transcatheter aortic valve replacement (TAVR) is approved for all patient risk profiles and is an option for all patients irrespective of age. However, patients enrolled in the low- and intermediate-risk trials were in their 70s, and those in the high-risk trials were in their 80s. TAVR has never been systematically tested in young (<65 years), low-risk patients. Unanswered questions remain, including the safety and effectiveness of TAVR in patients with bicuspid aortic valves; future coronary access; durability of transcatheter heart valves; technical considerations for surgical transcatheter heart valve explantation; management of concomitant conditions such as aortopathy, mitral valve disease, and coronary artery disease; and the safety and feasibility of future TAVR-in-TAVR. The authors predict that balancing these questions with patients’ clear preference for less invasive treatment will become common. In this paper, the authors consider each of these questions and discuss risks and benefits of theoretical treatment strategies in the lifetime management of young patients with severe aortic stenosis.  相似文献   
995.
Summary The reactivity of D-14 monoclonal antibody (mAb) to a specific epitope of carcinoembryonic antigen (CEA) was evaluated on formalin-fixed, paraffin-embedded tissues. A total of 52 normal tissues, 90 colorectal carcinomas and 127 non-colorectal neoplasms were tested using the peroxidase/antiperoxidase technique. D-14 mAb did not react with normal tissues apart from producing a weak staining of normal colonic glands immediately adjacent to the neoplastic structures. All 61 primary and 29 metastatic colorectal carcinomas expressed the carcinoembryonic antigen. However, there was considerable heterogeneity in cellular antigen expression in both primary and metastatic colorectal carcinomas with 10%–99% of tumor cells staining. Of 22 stomach adenocarcinomas, 14 were also immunoreactive, as were 2 of 5 pancreatic carcinomas. Only 6 of 100 neoplasms of non-gastrointestinal origin expressed weak to moderate immunoreactivity. In 7 cases, colorectal micrometastases not recognized in conventional hematoxylin and eosin slides could be identified with D-14 mAb. The specificity of this antibody could be used in differentiating colorectal carcinomas from other types of tumors, including adenocarcinoma from other sites.This paper was presented at the 1989 Annual Meeting of the American Association for Cancer Research Inc., San Francisco, California  相似文献   
996.
Background: Percutaneous coronary rotational atherectomy (PCRA) is a potent stimulus of platelet activation and aggregation in vivo. For this reason, many patients undergoing PCRA are treated with platelet glycoprotein (GP) IIb/IIIa inhibitors. However, there is limited data regarding the ability of GP IIb/IIIa inhibitors to reduce ischemic complications of PCRA and no data regarding their effect on long-term survival.Methods: Data on 1138 consecutive patients undergoing PCRA in 5 hospitals in 1998–1999 were pooled and analyzed. Long-term survival was available for all 530 patients treated in 3 of the hospitals.Results and conclusions: GP IIb/IIIa inhibitors were administered to 315 of 1138 (28%) PCRA patients. There was no difference in age, gender or race among patients treated with and without GP IIb/IIIa antagonists. The prevalence of hypertension, diabetes, renal insufficiency and peripheral vascular disease did not differ between groups. Unstable angina was more common among patients treated with GP IIb/IIIa inhibitors (45% vs. 38%, P = 0.036)Patients treated with GP IIb/IIIa inhibitors had lower ejection fractions (50% vs. 55%, P < 0.001) and more 3-vessel coronary disease (24% vs. 16%, P = 0.002). Angiographic success was over 99% in both groups (P = NS). The frequency of major adverse cardiovascular events (MACE) was slightly greater in GP IIb/IIIa inhibitor treated patients (3.8% vs. 2.2%, P = 0.126). At a mean follow-up of 3 years, mortality was 13.3% in the GP IIb/IIIa treated patients and 12% in the untreated patients (P = 0.224). On Cox proportional hazards analysis, treatment with a GP IIb/IIIa inhibitor was not significantly associated with increased survival (Hazard Ratio, 0.81, 95% Confidence Interval, 0.631–1.039, P = 0.098). These data do not indicate a significant association between GP IIb/IIIa inhibitor treatment during PCRA and MACE or survival.Condensed Abstract. There is limited data regarding the ability of GP IIb/IIIa inhibitors to reduce ischemic complications of percutaneous coronary rotational atherectomy (PCRA) and no data regarding their effect on long-term survival. These data do not indicate a significant association between GP IIb/IIIa inhibitor treatment during PCRA and MACE or survival.  相似文献   
997.
Women with polycystic ovary syndrome (PCOS) undergoing ovulation induction appear to be extremely sensitive to gonadotropin stimulation and at increased risk for ovarian hyperstimulation syndrome. To determine granulosa cell responsiveness to recombinant human FSH (r-hFSH), dose-response studies were conducted in 16 individual PCOS patients and 7 normal women. Each subject received an iv injection of r-hFSH at doses of 0, 37.5, 75, or 150 IU in a randomized fashion on four separate occasions. Blood samples were obtained at frequent intervals before and for 24 h after r-hFSH administration for measurement of gonadotropins and steroid hormones. Our results showed that administration of r-hFSH produced instantaneous and equivalent dose-related increases in serum FSH in PCOS and normal women, which were followed by similar exponential decreases to baseline levels within 24 h in both groups. In PCOS subjects, the peak mean incremental response of serum estradiol (E(2)) to 150 IU of r-hFSH was 1.8-fold greater (P < 0.0001) and considerably accelerated compared with that found in normal women. In contrast, E(2) responses to 37.5 IU and 75 IU were similar between groups. Regression analysis of maximal E(2) concentrations in response to r-hFSH in each individual subject revealed that the slope of the linear trend line in the group of women with PCOS (r = 0.82) was significantly greater (P < 0.01) than that of normal controls (r = 0.71). The time-course of response revealed that in PCOS women, increases of E(2) were not sustained, compared with those of normal controls, because peak concentrations were followed by an estimated 40% decrement in circulating levels, whereas E(2) levels in normal women persisted for 24 h after reaching maximal values. These findings indicate that women with PCOS exhibit a significantly greater capacity for E(2) production in response to iv r-hFSH, compared with normal women. In PCOS, E(2) production was relatively transient because after peak concentrations a marked decline was detected at each dose, unlike normal women who exhibited persistent elevations of E(2) for up to 24 h. That this distinction was dose-dependent supports the concept of an FSH dose-response threshold, beyond which PCOS but not normal women are susceptible to ovarian hyperresponsiveness.  相似文献   
998.
Estrogens influence the differentiation and maintenance of reproductive tissues and affect lipid metabolism and bone remodeling. Two estrogen receptors (ERs) have been identified to date, ERα and ERβ. We previously generated and studied knockout mice lacking estrogen receptor α and reported severe reproductive and behavioral phenotypes including complete infertility of both male and female mice and absence of breast tissue development. Here we describe the generation of mice lacking estrogen receptor β (ERβ −/−) by insertion of a neomycin resistance gene into exon 3 of the coding gene by using homologous recombination in embryonic stem cells. Mice lacking this receptor develop normally and are indistinguishable grossly and histologically as young adults from their littermates. RNA analysis and immunocytochemistry show that tissues from ERβ −/− mice lack normal ERβ RNA and protein. Breeding experiments with young, sexually mature females show that they are fertile and exhibit normal sexual behavior, but have fewer and smaller litters than wild-type mice. Superovulation experiments indicate that this reduction in fertility is the result of reduced ovarian efficiency. The mutant females have normal breast development and lactate normally. Young, sexually mature male mice show no overt abnormalities and reproduce normally. Older mutant males display signs of prostate and bladder hyperplasia. Our results indicate that ERβ is essential for normal ovulation efficiency but is not essential for female or male sexual differentiation, fertility, or lactation. Future experiments are required to determine the role of ERβ in bone and cardiovascular homeostasis.  相似文献   
999.
ABSTRACT

Half of HIV-positive persons in Russia are on antiretroviral therapy (ART), and only 27% are virally suppressed. A feasibility pilot intervention to mobilize social capital resources for HIV care support was conducted in St. Petersburg. Out-of-care or ART-nonadherent HIV-positive persons (n?=?24) attended a five-session intervention to increase access social capital resources (i.e., family, friends, or providers) to mobilize supports for entering care, initiating care, and adhering to ART. HIV care indicators were assessed at baseline, an immediate followup (FU-1), and 6-month followup (FU-2) points. At FU-1, participants more frequently discussed their care experiences with others, verifying the intervention’s mechanism of action. Participants increased in scales of medication taking adherence (p?=?0.002, FU-1; p?=?0.011, FU-2), self-efficacy (p?=?0.042; FU-1), and outcome expectancies (p?=?0.016, FU-2). Among persons not on ART, HIV Medication Readiness scale scores increased at FU-1 (p?=?0.032) but became attenuated at FU-2. Participants tended to more frequently keep care appointments (79%, baseline to 90%, FU-1, p?=?0.077); to have undetectable viral load (54%, baseline to 74%, FU-2; p?=?0.063); and to have fewer past-month days with delayed or incomplete medication doses (7.8, baseline to 4.2, FU-1; p?=?0.084). This novel social capital intervention is promising for improving HIV care-related outcomes and warrants a full-scale evaluation.  相似文献   
1000.
Three hundred nine patients were followed during their recovery area stay after percutaneous coronary intervention. Recovery area times for patients who received bivalirudin during percutaneous coronary intervention showed an average reduction in total recovery area length of stay of 36 minutes (p <0.0001) compared with patients who received heparin alone. This reduction was also seen when compared with the heparin + abciximab group (46-minute reduction, p = 0.0007), and the heparin + eptifibatide group (35-minute reduction, p = 0.0005). Patients who received bivalirudin took significantly less time for the activated clotting time (ACT) to normalize despite significantly higher average ACTs and significantly fewer subtherapeutic ACTs.  相似文献   
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