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991.
Genotypic diversity among 26 isolates of Bartonella bacilliformis obtained from different areas of Peru, and at different times, was assessed by comparison of DNA sequences derived from 16S-23S ribosomal DNA intergenic spacer regions (ISR) and a citrate synthase gene (gltA) fragment and by amplified fragment length polymorphism (AFLP) analysis. gltA comparison divided the isolates into two groups, whereas ISR comparison revealed six sequences. AFLP analysis using a selective primer delineated five profiles that correlated well with those obtained by sequence comparison. Combination of all three data sets divided the isolates into six genotypes. One of these genotypes was common to isolates collected from a large area in western Peru that corresponded to the region of endemicity for bartonellosis; however, isolates belonging to two other genotypes were also found within this region. Two of these genotypes were found in isolates isolated more than 35 years apart. The remaining three genotypes were each specifically associated with three outbreaks of bartonellosis that have recently occurred in areas where the disease had not previously been recognized. Demonstration of the unique nature of these isolates indicates that the outbreaks with which they were associated did not result from the introduction of disease by individuals who acquired their infection in the recognized region of endemicity. The sources of these outbreaks remain unknown. A consensus approach to bacterial typing using comparative sequence analysis of multiple genetic loci and the pan-genomic sampling of AFLP appears to offer a well-supported assessment of B. bacilliformis diversity, and the genotypic differences identified appear to have epidemiological significance.  相似文献   
992.
We report on a new Actinobaculum species, "Actinobaculum massiliae," isolated from the urine of an elderly woman with recurrent cystitis. Its phenotypic pattern was similar to those of both of the other Actinobaculum species described to date. On 16S rRNA sequencing, the Marseille isolate shared 95% homology with Actinobaculum suis, 92 to 93% homology with Actinobaculum schaalii, 91 to 92% homology with Arcanobacterium spp., and 87 to 90% homology with Actinomyces species. A bootstrap value of 99% supports the node separating the Actinobaculum sp. from its closest neighbor (A. suis). In conclusion, on the basis of phenotypic, genotypic, and phylogenetic assessments, we show that the Marseille isolate is a previously unrecognized organism within the Actinobaculum genus, and we propose placement of the organism in the taxon "Actinobaculum massiliae."  相似文献   
993.
994.
OBJECTIVE: To understand the national utilization pattern of heat and moisture exchangers (HME) and heated humidifiers (HH) in mechanically ventilated ICU patients. DESIGN: Cross-sectional survey. POPULATION: ICU directors in French and Canadian university-affiliated hospitals. Response rate was 89%. MEASUREMENTS: We asked respondents whether they primarily used HME or HH. We recorded whether HME were used in all patients and for how long, how often they were changed, for whom, and why they were not used. RESULTS: HME were used more often in France HH in Canada. HME were more likely to be used for all patients in France than in Canada (63% vs. 13% and for any duration of ventilation (93% vs. 35%). Short-term use of HME was more common in Canada than in France (59% vs. 7%). HME were primarily changed every day in both countries. The patients for whom HME were not used and reasons for nonutilization were similar in France and Canada. The variable of country was the strongest predictor of HME utilization for every patient (France vs. Canada, odds ratio 11) and utilization for periods of 5 days or less (Canada vs. France, odds ratio 22). CONCLUSIONS: HME were reportedly used more in often in France than in Canada for the entire duration of mechanical ventilation. This survey highlights perceptions and practices related to the determinants and consequences of airway humidification and suggests differences in the cost of mechanical ventilation between countries  相似文献   
995.
996.
We aimed to assess the psychiatric profile and prognostic value of psychiatric disorders (PDs) in patients presenting with unexplained syncope. Forty patients with recurrent unexplained syncope referred for head-up tilt testing were compared with age- and sex-matched patients free of known chronic PDs referred for arrhythmia. All patients underwent a semistandardized psychiatry questionnaire (Mini-International Neuropsychiatric Interview) to assess their profile. Additional stress coping was performed to study adaptational processes to stressful situations. After tilt testing and psychiatric evaluation, a drug-free follow-up was performed in patients with syncope. Of the 80 patients who referred to the psychiatric interview, 40 had evidence of at least 1 psychiatric disorder. They were 26 patients (65%) in the syncope group and 14 patients (35%) in the control group (p = 0.01). Detailed analysis revealed a more frequent subprofile of anxiety and panic disorders in patients with syncope than in controls (30% vs 12% and 20% vs 10%, respectively), whereas the subprofile of depression was similar in both groups. Moreover, those with syncope were more likely to have a high anxiety index (25 +/- 5 vs 22 +/- 4, p = 0.004), and were more prone to avoidance-oriented coping strategies when experiencing undesirable life events than controls. Considering syncope patients, no difference could be found between the 25 with a positive tilt test and the 15 with a negative tilt test with respect to the number of syncopal episodes and psychiatric profile. After a 3-year drug-free follow-up, 15 patients (37.5%) had at least 1 recurrent syncope. The recurrence rate was similar in patients with positive and negative head-up tilt test results (9 of 25 vs 6 of 15, respectively). In contrast, the syncopal recurrence rate was higher in patients who fulfilled criteria for affective disorders (13 of 26 vs 2 of 14, 95% confidence interval 1.09 to 2.55, relative risk 1.7, p = 0.04). Thus, patients with recurrent unexplained syncope are more anxious and are more prone to panic disorders and avoidance-oriented coping strategies than control patients with arrhythmia. The presence of a psychiatric disorder is associated with an increased risk of recurrence. The outcome of such patients may be improved with recognition and treatment of PDs.  相似文献   
997.
998.
4,2'-(Methoxyphenyl)-1-[2'-(N-2"-pyridinyl)-p-fluorobenzamido]ethylpiperazine ((18)F-MPPF) is a radiotracer used in clinical PET studies for the visualization of serotonin-1A (5-HT(1A)) receptors. In a previous study, we demonstrated that a rapid enhancement of extracellular serotonin concentrations influences (18)F-MPPF-specific binding. Because endogenous serotonin is significantly decreased in some pathologies, the aim of this study was to determine whether (18)F-MPPF is sensitive to depletion of this neurotransmitter. METHODS: Using the beta-microprobe, an original beta(+)-sensitive intracerebral probe, and microdialysis, the effect of decreased serotonin on the specific binding of (18)F-MPPF to 5-HT(1A) receptors was investigated in the hippocampus of the anesthetized rat. Extracellular serotonin was pharmacologically decreased in the hippocampus after a single injection of p-ethynylphenylalanine ([p-EPA] 5 mg/kg), a new tryptophan hydroxylase inhibitor. RESULTS: Our results showed that the (18)F-MPPF-specific binding was significantly enhanced after the decrease of extracellular serotonin. These results were confirmed by the (18)F-MPPF distribution in cerebral tissues (hippocampus-to-cerebellum ratio) and by the decrease of the extracellular (18)F-MPPF collected in hippocampal dialysates. CONCLUSION: This study further supports the view that (18)F-MPPF binding potential is increased in the hippocampus if the endogenous serotonin is pharmacologically decreased after a p-EPA injection. This phenomenon will be an additional factor in the interpretation of the results from (18)F-MPPF clinical PET studies.  相似文献   
999.
OBJECTIVE: To assess the viability of a strategy of primary resection with secondary liver transplantation (LT) for hepatocellular carcinoma (HCC) on cirrhosis. SUMMARY BACKGROUND DATA: LT is the optimal treatment of HCC with cirrhosis. Owing to organ shortage, liver resection is considered as a reasonable first-line treatment of patients with small HCC and good liver function, with secondary LT as a perspective in case of recurrence. The viability of such strategy, positively explored in theoretical models, is not documented in clinical practice. METHODS: Among 358 consecutive patients with HCC on cirrhosis treated by liver resection (n = 163; 98 of whom were transplantable) or transplantation (n = 195), the feasibility and outcome of secondary transplantation was evaluated in a 2-step fashion. First, secondary LT for tumor recurrence after resection (n = 17) was compared with primary LT (n = 195), to assess the risk and the outcome of secondary LT in patients who effectively succeeded to be treated by this approach. Second, primary resection in transplantable patients (n = 98) was compared with that of primary LT (n = 195) on an intention-to-treat basis, to assess the outcome of each treatment strategy and to determine the proportion of resected patients likely to be switched for secondary LT. Transplantability of resected patients was retrospectively determined according to selection criteria of LT for HCC. RESULTS: Operative mortality (< or =2 months) of secondary LT was significantly higher than that of primary LT (28.6% versus 2.1%; P = 0.0008) as was intraoperative bleeding (mean transfused blood units, 20.7 versus 10.5; P = 0.0001). Tumor recurrence occurred more frequently after secondary than after primary LT (54% versus 18%; P = 0.001). Posttransplant 5-year overall survival was 41% versus 61% (P = 0.03), and disease-free survival was 29% versus 58% (P = 0.003) for secondary and primary LT, respectively.Of 98 patients treated by resection while initially eligible for transplantation, only 20 (20%) were secondarily transplanted, 17 of whom (17%) for tumor recurrence and 3 (3%) for hepatic decompensation. Transplantability of tumoral recurrence was 25% (17 of 69 recurrences). Compared with primarily transplanted patients, transplantable resected patients had a decreased 5-year overall survival (50% versus 61%; P = 0.05) and disease-free survival (18% versus 58%; P < 0.0001), despite the use of secondary LT.On a multivariate analysis including 271 patients eligible for transplantation and treated by either liver resection or primary LT, liver resection alone (P < 0.0001; risk ratio [RR] = 3.27) or liver resection with secondary LT (P < 0.05; RR= 1.87) emerged as negative independent factors of disease-free survival as compared with primary LT. A number of nodules > 3 (P = 0.002; RR= 2.02) and a maximum tumor size exceeding 30 mm (P < 0.0001; RR=1.93) were also predictive of lower disease-free survival. CONCLUSIONS: LT after liver resection is associated with a higher operative mortality, an increased risk of recurrence, and a poorer outcome than primary LT. In addition, liver resection as a bridge to LT impairs the patient transplantability and the chance of long-term survival of cirrhotic patients with HCC. Primary LT should therefore remain the ideal choice of treatment of a cirrhotic patient with HCC, even when the tumor is resectable.  相似文献   
1000.
OBJECT: Endovascular and surgical treatment must be clearly defined in the management of anterior communicating artery (ACoA) aneurysms. In this study the authors report their recent experience in using a combined surgical and endovascular team approach for ACoA aneurysms, and compare these results with those obtained during an earlier period in which surgical treatment was used alone. Morbidity and mortality rates, causes of unfavorable outcomes, and morphological results were also assessed. METHODS: The prospective study included 223 patients who were divided into three groups: Group A (83 microsurgically treated patients, 1990-1995); Group B (103 microsurgically treated patients, 1996-2000); and Group C (37 patients treated with Guglielmi Detachable Coil [GDC] embolization, 1996-2000). Depending on the direction in which the aneurysm fundus projected, the authors attempted to apply microsurgical treatment to Type 1 aneurysms (located in front of the axis formed by the pericallosal arteries). They proposed the most adapted procedure for Type 2 aneurysms (located behind the axis of the pericallosal arteries) after discussion with the neurovascular team, depending on the physiological status of the patient, the treatment risk, and the size of the aneurysm neck. In accordance with the classification of Hunt and Hess, the authors designated those patients with unruptured aneurysms (Grade 0) and some patients with ruptured aneurysms (Grades I-III) as having good preoperative grades. Patients with Grade IV or V hemorrhages were designated as having poor preoperative grades. By performing routine angiography and computerized tomography scanning, the causes of unfavorable outcome (Glasgow Outcome Scale [GOS] score < 5) and the morphological results (complete or incomplete occlusion) were analyzed. Overall, the clinical outcome was excellent (GOS Score 5) in 65% of patients, good (GOS Score 4) in 9.4%, fair (GOS Score 3) in 11.6%, poor (GOS Score 2) in 3.6%, and fatal in 10.3% (GOS Score 1). Among 166 patients in good preoperative grades, an excellent outcome was observed in 134 patients (80.7%). The combined permanent morbidity and mortality rate accounted for up to 19.3% of patients. The rates of permanent morbidity and death that were related to the initial subarachnoid hemorrhage were 6.2 and 1.5% for Group A, 6.6 and 1.3% for Group B, and 4 and 4% for Group C, respectively. The rates of permanent morbidity and death that were related to the procedure were 15.4 and 1.5% for Group A, 3.9 and 0% for Group B, and 8 and 8% for Group C, respectively. When microsurgical periods were compared, the rate of permanent morbidity or death related to microsurgical complications decreased significantly (Group A, 11 patients [16.9%] and Group B, three patients [3.9%]); Fisher exact test, p = 0.011) from the period of 1990 to 1995 to the period of 1996 to 2000. The combined rate of morbidity and mortality that was related to the endovascular procedure (16%) explained the nonsignificance of the different rates of procedural complications for the two periods, despite the significant decrease in the number of microsurgical complications. Among 57 patients in poor preoperative grade, an excellent outcome was observed in 11 patients (19.3%); however, permanent morbidity (GOS Scores 2-4) or death (GOS Score 1) occurred in 46 patients (80.7%). With regard to the correlation between vessel occlusion (the primary microsurgical complication) and the morphological characteristics of aneurysms, only the direction in which the fundus projected appeared significant as a risk factor for the microsurgically treated groups (Fisher exact test: Group A, p = 0.03; Group B, p = 0.002). The difference between endovascular and microsurgical procedures in the achievement of complete occlusion was considered significant (chi2 = 6.13, p = 0.01). CONCLUSIONS: The direction in which the fundus projects was chosen as the morphological criterion between endovascular and surgical methods. The authors propose that microsurgical clip application should be the preferred option in the treatment of ACoA aneurysms with anteriorly directed fundi and that endovascular packing be selected for those lesions with posteriorly directed fundi, depending on morphological criteria.  相似文献   
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