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The outbreaks of rabies in humans transmitted by Desmodus rotundus in 2004 and 2005, in the northeast of the Brazilian State of Para, eastern Amazon basin, made this a priority area for studies on this zoonosis. Given this, the present study provides data on this phenomenon in an urban context, in order to assess the possible circulation of the classic rabies virus (RABV) among bat species in Capanema, a town in the Amazon basin. Bats were collected, in 2011, with mist nets during the wet and dry seasons. Samples of brain tissue and blood were collected for virological and serological survey, respectively. None of the 153 brain tissue samples analyzed tested positive for RABV infection, but 50.34% (95% CI: 45.67-55.01%) of the serum samples analyzed were seropositive. Artibeus planirostris was the most common species, with a high percentage of seropositive individuals (52.46%, 95% CI: 52.31 52.60%). Statistically, equal proportions of seropositive results were obtained in the rainy and dry seasons (c2 = 0.057, d.f. = 1, p = 0.88). Significantly higher proportions of males (55.96%, 95% CI: 48.96-62.96%) and adults (52.37%, 95% CI: 47.35-57.39%) were seropositive. While none of the brain tissue samples tested positive for infection, the high proportion of seropositive specimens indicates that RABV may be widespread in this urban area.  相似文献   
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Objective

The objective of this study was to analyze the impact of advanced imaging applications and cone beam computed tomography (CBCT) on radiation exposure of the patient and operator and detection of technical problems during fenestrated-branched endovascular aortic repair (F-BEVAR) for treatment of pararenal aneurysms and thoracoabdominal aortic aneurysms (TAAAs).

Methods

We reviewed the clinical data of 386 consecutives patients (289 male; mean age, 75 ± 8 years) treated by F-BEVAR for 196 pararenal aneurysms and 190 TAAAs (mean, 3.4 ± 0.9 targeted vessels/patient) between 2007 and 2017. Radiation exposure (cumulative air kerma) was analyzed in three fixed imaging systems used between 2007 and 2011 (system 1), 2012 and 2016 (system 2), and 2016 and 2017 (system 3). Onlay fusion and CBCT were available with systems 2 and 3, whereas digital zoom with fusion overlay was used with system 3. Operator effective dose was measured per month using a radiation dosimeter badge. Computed tomography angiography and CBCT were analyzed for findings requiring immediate revision or secondary interventions. End points were patient radiation exposure; operator effective dose; procedure technical success; and 30-day rates of mortality, major adverse events, and secondary interventions.

Results

F-BEVAR was performed using system 1 in 98 patients, system 2 in 198 patients, and system 3 in 90 patients. Use of onlay fusion/CBCT was 0% with system 1, 42% with system 2, and 98% with system 3. Procedures performed with onlay fusion/CBCT had significantly (P < .05) higher technical success (99.4% vs 98.8%) and lower contrast material volume (155 ± 58 mL vs 172 ± 80 mL), fluoroscopy time (83 ± 34 minutes vs 94 ± 49 minutes), and cumulative air kerma (2561 ± 1920 mGy vs 3767 ± 2307 mGy). Despite higher case volume and increasing complexity during the experience, operator effective dose decreased to 9 ± 4 × 10?2 mSv/case with system 3 compared with 26 ± 3 × 10?2 mSv/case with system 1 and 20 ± 2 × 10?2 mSv/case with system 2 (P = .001). Among 219 patients who had no CBCT, 18 (8%) had computed tomography angiography findings that prompted secondary interventions before dismissal. Conversely, among 167 patients who had CBCT, 14 patients (8%) had intraoperative CBCT findings requiring immediate revision, with no additional secondary interventions. Patients treated with onlay fusion/CBCT had significantly (P < .05) lower mortality (4% vs 1%), major adverse events (43% vs 19%), and secondary interventions (10% vs 4%) at 30 days.

Conclusions

Radiation exposure and operator effective dose significantly decreased with evolution of F-BEVAR experience and use of advanced imaging applications such as onlay fusion and CBCT. CBCT allowed immediate assessment and identified intraoperative technical problems, leading to immediate revision and avoiding early secondary interventions.  相似文献   
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Brain metastases are a major cause of melanoma-related mortality and morbidity. We undertook whole-exome sequencing of 50 tumours from patients undergoing surgical resection of brain metastases presenting as the first site of visceral disease spread and validated our findings in an independent dataset of 18 patients. Brain metastases had a similar driver mutational landscape to cutaneous melanomas in TCGA. However, KRAS was the most significantly enriched driver gene, with 4/50 (8%) of brain metastases harbouring non-synonymous mutations. Hotspot KRAS mutations were mutually exclusive from BRAFV600, NRAS and HRAS mutations and were associated with a reduced overall survival from the resection of brain metastases (HR 10.01, p = 0.001). Mutations in KRAS were clonal and concordant with extracranial disease, suggesting that these mutations are likely present within the primary. Our analyses suggest that KRAS mutations could help identify patients with primary melanoma at higher risk of brain metastases who may benefit from more intensive, protracted surveillance.Subject terms: CNS cancer, Metastasis, Melanoma, Tumour biomarkers, Cancer  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - To compare the blood flow situation in primary open-angle glaucoma (POAG) and pseudoexfoliation glaucoma (PXG) using optical...  相似文献   
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Traditional implantation techniques of assist devices from the apex of left ventricle to the ascending or descending aorta are highly invasive and carry substantial complications for end‐stage heart failure patients. This study has shown that the descending aorta can be a promising location to install an implantable mechanical circulatory support with minimally invasive surgery. Herein, the hemodynamic effect of an in‐house prototyped pump implanted in the descending aorta was investigated numerically as well as experimentally. The objective of the experimental study is met by using the in‐house simulator of the cardiovascular loop replicating congestive heart failure conditions. The objective of the numerical study was met by using the modified version of the concentrated lumped parameter model developed by the same team. The results show that the pump placement in the descending aorta can lead to an improvement in pulsatility. The pressure drop, generated at the upstream of the pump, facilitates the cardiac output as a result of after‐load reduction, but at the same time, it induces a slight drop in the carotid as well as the coronary perfusion. The pressure rise, generated at the downstream of the pump, improves the blood perfusion in the renal circulation.  相似文献   
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