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991.
OBJECTIVE: To analyze the genetic contribution of HLA in development of psoriatic arthritis (PsA) and to study whether MICA is primarily associated with PsA or whether its association is secondary to linkage disequilibrium with centromeric genes, such as MICB, TNFA, or HLA-DRB1. METHODS: DNA samples from 81 Spanish patients with PsA and 110 healthy controls were examined by polymerase chain reaction (PCR) sequence-specific primers to type HLA-Cw and HLA-DRB1, PCR sequence-specific oligonucleotides to determine HLA-B, and PCR restriction fragment length polymorphism for tumor necrosis factor-alpha promoter polymorphisms at positions -238 and -308. Analysis of microsatellite polymorphisms in the transmembrane region of MICA and in intron 1 of MICB was also carried out. RESULTS: HLA-Cw*0602 was significantly increased in PsA [60% vs 17%; p(c) < 0.00002, OR 7.33, etiological fraction (EF) 0.52]. MICA-A9 (60% vs 30%; p(c) = 0.0002, OR 3.57, EF 0.43) and the microsatellite MICB-CA-22 allele (23% vs 7%; p(c) = 0.028, OR 3.9, EF 0.17) were also significantly increased in PsA. MICA-A9 was in linkage disequilibrium with MICB-CA-22 (delta = 0.6). The association of MICA-A9 was independent of MICB-CA-22 and Cw*0602, since it was also associated in MICB-CA-22 negative (p(c) = 0.0015, OR 2.96, EF 0.34) and in Cw*0602 negative patients (p(c) = 0.034, OR 2.83, EF 0.34). TNFA and DRB I alleles were not significantly associated with PsA. CONCLUSION: Cw*0602 and MICA-A9 appear to be the strongest genetic susceptibility factors for PsA. However, MICA-A9 was associated independently of Cw6. HLA-B alleles and MICB-CA22 are associated secondarily to linkage with MICA. TNFA and HLA-DRB1 were not associated with PsA susceptibility, and our data suggest that their reported association may only reflect the linkage disequilibrium with MICA-A9 among the different populations studied.  相似文献   
992.
OBJECTIVES: To understand the role of Gemella species as a pathogen causing extra-abdominal infections in the Hospital General Universitario Gregorio Mara?ón. MATERIALS AND METHODS: Between 1994 and 1998, one or more isolates of Gemella sp. were found in 128 patients. The 113 patients with isolates from nonsignificant specimens or representing intra-abdominal infections were excluded. The clinical records of the remaining 15 patients were reviewed as well as the more recent literature. RESULTS: Mean age of patients was 41 years. The underlying conditions most frequently noted were intravenous drug users (n=6; 3 positive for human immunodeficiency virus), alcoholism (n=2), cardiovascular disease (n=2), chronic lung disease (n=2), diabetes (n=1), kidney transplant (n=1). The extra-abdominal infections were skin and soft tissue abscess (n=5), empyema (n=4), brain abscess (n=2), primary bacteremia (n=1), lung abscess (n=1), septic thrombophlebitis (n=1), complicated urinary tract infection (n=1). The infection was monomicrobial in six and polymicrobial in nine cases. Surgical drainage and betalactam antibiotics were used. The outcome was favorable in almost all cases. CONCLUSIONS: Gemella sp. should be included as a cause of localized soft-tissue abscesses, empyema, and bloodstream infection. No case of infective endocarditis was found. Although it is susceptible to several antibiotics, Gemella sp. requires a careful microbiologic diagnosis and a subtle clinical interpretation.  相似文献   
993.
BACKGROUND: Tuberculosis (TB) recurrences can be due to either reactivation by the same strain (standard assumption) or reinfection by a new strain. Reinfection has mainly been studied in selected populations with a high risk of reexposure to TB. Our aim was to analyze the role of reinfection in TB recurrences in unselected populations, without the clinical/epidemiological circumstances that favor the involvement of a new different strain of Mycobacterium tuberculosis in the recurrence. METHODS: A molecular typing analysis was performed with 92 sequential isolates of M tuberculosis from 43 patients with recurrent TB, during a 12-year period. The subjects were both positive and negative for the human immunodeficiency virus, most did not adhere to anti-TB therapy, and they lived in an area with a moderate incidence of TB. Recurrence was considered as being caused by reinfection when the molecular fingerprints for the strains involved in the sequential episodes of TB were different. RESULTS: In 14 (33%) of the 43 patients, different M tuberculosis strains were involved in the first and in subsequent episodes of TB. Reinfection was found for patients who were both positive and negative for the human immunodeficiency virus, and most patients did not adhere to anti-TB therapy. Differences between the reinfection and reactivation groups were not significant (P =.77) according to the time interval between episodes. CONCLUSIONS: Reinfection plays an important role in recurrent TB in a population without the clinical/epidemiological circumstances that are usually assumed to favor it. Reinfection should, thus, be considered as a cause of TB recurrences in a wider context than before.  相似文献   
994.
Background Percutaneous coronary interventions (PCIs) in patients with multivessel coronary artery disease (CAD) may be staged or performed in a single session. No data exist about the relative safety and efficacy of these 2 strategies. Our aim was to compare short-term and long-term outcomes of patients with multivessel CAD who underwent PCI in 1 versus 2 sessions. Methods and Results The study included 264 consecutive patients who underwent treatment in our center during 1997 and 1998. PCI was conducted in a single session in 129 patients and was staged in 135 patients. The mean interval between the sessions in the staged group was 45.6 ± 22.3 days. The rates of major adverse cardiac events (MACEs) during in-hospital stay did not differ significantly between the staged (combined for both stages) and nonstaged groups (2.2% vs 4.6%; P = .28). A trend for lower event rates at 30-day (2.9% vs 6.9%; P = .13) and 1-year follow-up (26.1 vs 35.9; P = .08) favored the staged arm. Diameter stenosis ≥50% was found in 17% of patients in the staged group in the second session and was successfully retreated in most of them. No MACE occurred between the sessions. Multivariate analysis identified staging of the procedure as a single independent predictor of MACE at 1-year follow-up (P = .05). Conclusion Our results suggest that a practical staging strategy within 4 to 8 weeks is safe and allows for identification and treatment of potential excessive proliferative response in the previously intervened lesions during the second procedure. (Am Heart J 2002;143:1017-26.)  相似文献   
995.
OBJECTIVES: We compared the effectiveness and cost of percutaneous occlusion using an Amplatzer septal occluder (ASO) (AGA Medical Corp., Golden Valley, Minnesota) device compared with surgical closure of an ostium secundum atrial septal defect (ASD II) in Guatemala. BACKGROUND: The percutaneous occlusion of ASD II in first-world nations seems to offer better clinical results and lower cost compared with surgical closure. METHODS: We reviewed the clinical course of 111 patients referred to our institution for closure of isolated ASD II. Successful closure was assessed immediately after the procedures and at 12 months. Actual hospital costs were calculated for every patient who underwent either of the two procedures. RESULTS: Eighty-three patients with ASD II (75%) were selected for percutaneous occlusion with the ASO device, and the remaining 28 patients (25%) underwent surgical closure. In the device group, in 72 patients (86.7%) devices were successfully deployed. At immediate and 12-month follow-up, the complete closure rate was 87.5% (63 of 72 patients) and 97.2% (70 of 71 patients), respectively. In the surgical group, all patients had successful closure immediately after the procedure and at 12 months. Surgical closure offered a 27% cost savings in comparison with percutaneous occlusion (U.S. 3,329.50 dollars +/- 411.30 dollars and U.S. 4,521.03 dollars +/- 429.71 dollars; p < 0.001, respectively). Cost of the device (U.S. 2,930.00 dollars) proved to be the main cause for this difference. CONCLUSIONS: We confirmed the clinical advantages of percutaneous occlusion over surgical closure of ASD II. However, percutaneous occlusion costs were higher compared with surgical closure. In Guatemala, where health care resources are limited, ASD II closure with the ASO device did not prove to be cost-effective.  相似文献   
996.
Klebsiella bacteremia: an analysis of 100 episodes   总被引:7,自引:0,他引:7  
During a five-year period, 204 patients had klebsiella bacteremia at this institution; these cases constituted 6.6% of the total episodes of bacteremia. The incidence was 2.3 cases per 1,000 admitted patients. A random group of 100 cases was chosen for analysis in the present study. The disease was community acquired in 23%, nosocomially acquired in 77%, unimicrobial in 88%, or part of a polymicrobial bacteremia in 12% of episodes. Three-quarters of the episodes were caused by Klebsiella pneumoniae and the remaining one-quarter, by Klebsiella oxytoca. Portals of entry, in decreasing order of frequency, were urinary, respiratory, and biliary tracts. Twenty-four percent of the Klebsiella isolates were resistant to gentamicin. The most frequent clinical finding (in 96% of the cases) was fever. Shock occurred in 22% and pyogenic metastatic foci, in 5% of the patients. None of the patients had evidence of disseminated intravascular coagulation. Overall mortality was 25%, and factors associated with poor prognosis were inadequacy of antimicrobial chemotherapy, septic shock, type of underlying disease, and clinical condition of the patients.  相似文献   
997.
PEDIATRIC RECTAL DIEULAFOY'S LESION   总被引:1,自引:0,他引:1  
Dieulafoy's lesions are an unusual cause of gastrointestinal hemorrhage. The overwhelming majority of lesions are found in the upper gastrointestinal tract, particularly along the lesser curvature of the stomach in the region supplied by the left gastric artery. Rectal Dieulafoy's lesions have never before been reported in the pediatric population, and our case represents only the third reported occurrence of a rectal Dieulafoy's lesion in the English medical literature. Successful treatment was administered, i.e. , the combination of sclero-therapy followed by thermocoagulation. We therefore recommend that rectal Dieulafoy's lesion be included in the differential diagnosis of children with severe rectal bleeding and that management follow the same principles used to treat upper gastrointestinal tract Dieulafoy's lesions: injection therapy followed by heater probe coagulation.  相似文献   
998.
OBJECTIVES: To evaluate the ability of quantitative perfusion cardiac magnetic resonance (CMR) to assess the hemodynamic significance of coronary artery disease (CAD) compared with well-established anatomic and physiologic techniques. BACKGROUND: Fractional flow reserve (FFR) is considered by many investigators to be a reliable stenosis-specific method to determine hemodynamically significant CAD. Quantitative perfusion CMR is a promising noninvasive approach to detect CAD but has yet to be validated against FFR. METHODS: This is a prospective study in patients with suspected CAD who underwent coronary angiography, FFR, and CMR assessments. The quantitative myocardial perfusion reserve (MPR) was calculated in 720 myocardial sectors (8 sectors/slice). The MPR was calculated from the ratio between stress and rest myocardial flow based on signal intensity time curves using deconvolution analysis. Stress was simulated with adenosine for both FFR and MPR. The MPR assessments were compared to FFR (n = 44 coronary segments) and quantitative coronary angiography (n = 108 segments) in the corresponding coronary territories. RESULTS: The MPR was 1.54 +/- 0.36 in segments with FFR < or =0.75 (n = 14) and 2.11 +/- 0.68 in those with FFR >0.75 (n = 30; p = 0.0054). An MPR cutoff of 2.04 was 92.9% (95% CI 77.9 to 100.0) sensitive and 56.7% (95% CI 32.8 to 80.6) specific in predicting a coronary segment with FFR < or =0.75. The MPR was 1.54 +/- 0.49 in coronary segments with > or =50% diameter stenosis (DS) (n = 47) and 2.13 +/- 0.80 in segments with <50% DS (n = 61; p < 0.001). An MPR cutoff of 2.04 was 85.1% (95% CI 71.1 to 99.2) sensitive and 49.2% (95% CI 33.6 to 64.8) specific in predicting CAD with > or =50% DS. CONCLUSIONS: Quantitative perfusion CMR is a safe noninvasive test that represents a stenosis-specific alternative to determine the hemodynamic significance of CAD.  相似文献   
999.
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