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1.

Background  

West Nile virus (WNv) has recently emerged as a health threat to the North American population. After the initial disease outbreak in New York City in 1999, WNv has spread widely and quickly across North America to every contiguous American state and Canadian province, with the exceptions of British Columbia (BC), Prince Edward Island and Newfoundland. In this study we develop models of mosquito population dynamics for Culex tarsalis and C. pipiens, and create a spatial risk assessment of WNv prior to its arrival in BC by creating a raster-based mosquito abundance model using basic geographic and temperature data. Among the parameters included in the model are spatial factors determined from the locations of BC Centre for Disease Control mosquito traps (e.g., distance of the trap from the closest wetland or lake), while other parameters were obtained from the literature. Factors not considered in the current assessment but which could influence the results are also discussed.  相似文献   
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BackgroundDeveloping a noninvasive clinical test to accurately diagnose kidney allograft rejection is critical to improve allograft outcomes. Urinary exosomes, tiny vesicles released into the urine that carry parent cells’ proteins and nucleic acids, reflect the biologic function of the parent cells within the kidney, including immune cells. Their stability in urine makes them a potentially powerful tool for liquid biopsy and a noninvasive diagnostic biomarker for kidney-transplant rejection.MethodsUsing 192 of 220 urine samples with matched biopsy samples from 175 patients who underwent a clinically indicated kidney-transplant biopsy, we isolated urinary exosomal mRNAs and developed rejection signatures on the basis of differential gene expression. We used crossvalidation to assess the performance of the signatures on multiple data subsets.ResultsAn exosomal mRNA signature discriminated between biopsy samples from patients with all-cause rejection and those with no rejection, yielding an area under the curve (AUC) of 0.93 (95% CI, 0.87 to 0.98), which is significantly better than the current standard of care (increase in eGFR AUC of 0.57; 95% CI, 0.49 to 0.65). The exosome-based signature’s negative predictive value was 93.3% and its positive predictive value was 86.2%. Using the same approach, we identified an additional gene signature that discriminated patients with T cell–mediated rejection from those with antibody-mediated rejection (with an AUC of 0.87; 95% CI, 0.76 to 0.97). This signature’s negative predictive value was 90.6% and its positive predictive value was 77.8%.ConclusionsOur findings show that mRNA signatures derived from urinary exosomes represent a powerful and noninvasive tool to screen for kidney allograft rejection. This finding has the potential to assist clinicians in therapeutic decision making.  相似文献   
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BACKGROUND: Infections and malignancies are important causes of mortality and morbidity in renal allograft recipients. Their risk increases with increasing immunosuppression. METHODS: In an attempt to quantitate the increase in the risk of these complications in association with antirejection therapy, we reviewed the records of all renal allograft recipients of our center transplanted during the cyclosporin era. We sub-divided the patients into three groups based on acute rejection episodes during the first 6 months posttransplant, and the treatment for acute rejection: those who did not develop AR--group 1 (n=168); those who had one or more episodes of acute rejection and were treated with high dose corticosteroids --group 2 (n=169); those who in addition to corticosteroids required cytolytics (OKT3) and/or other drugs--group 3 (n=141). RESULTS: 52% patients in group 1, 71% patients in group 2 and 86% patients in group 3 had one or more episodes of infection during the first 6 months posttransplantation. Relative risk for group 2 and 3 were 1.56 (P=0.0002) and 2.98 (P<0.00001), respectively. Infection/patient rates at 6 months were 0.67, 1.23, and 2.79 in groups 1, 2, and 3 respectively. Groups 1 and 2 had a similar number of cases with squamous and basal cell carcinoma, however, there were few cases with these malignancies in group 3. No case of lymphoma was seen in group 1; there were four cases in group 2 and nine in group 3. There was no significant difference in patient survival in group 1 and 2, however, patients in group 3 had a reduced patient survival (1 vs. 3 P<0.001, 2 vs. 3 P=0.067). Graft survival was best in group 1 and worst in group 3 (1 vs. 2 P<0.05; 1 vs. 3 P<0.00001; 2 vs. 3 P<0.01). CONCLUSIONS: In renal transplant recipients the risk of infections and lymphoma increases with increasing immunosuppression and hence mortality and morbidity associated with it. When adding a potent immunosuppressive agent to rescue a kidney one needs to consider the serious and at times fatal side effects given the modest beneficial effect on long-term outcome.  相似文献   
5.

Purpose

The computer generated recordings for 2 nights in 40 patients studied with the RigiScan device were reevaluated using the new RigiScan Plus software to test its value in improving the discrimination between psychogenic and organic erectile dysfunction.

Materials and Methods

Each man was evaluated for erectile dysfunction with a detailed medical and sexual history, physical examination, biothesiometry, plethysmography, 2 nights of ambulatory RigiScan monitoring and a psychological evaluation that usually included a private interview with the sexual partner. At the conclusion of evaluation each patient was broadly classified as having organic or psychogenic erectile dysfunction. The RigiScan reports were initially independently analyzed without the investigator's knowledge of the final diagnosis by determining the single best erectile event, with a minimal cutoff value of 60 percent erection for 5 minutes as necessary to be considered normal and the sum of measurements from the 2 nights. The original reading and final diagnosis were correlated. At this point the data were processed with the new RigiScan Plus software using 2 new measurements: 1) rigidity activity units and 2) tumescence activity units at the base and tip of the penis, and the results were correlated with the final diagnosis.

Results

Evaluation of the single best event again showed that tip rigidity was the best single predictor if the diagnostic criteria were modified to 70 percent tip rigidity for 5 minutes with an estimate of correct classification of 92.5 percent. Nearly the same accuracy was obtained by base single event rigidity, tip rigidity and base tumescence activity units (each 90 percent). The summary analysis of all erectile events during the 2 nights of evaluation that had a low correlation with the final diagnosis using the original software showed that the best overall predictor of final diagnosis was tip tumescence activity units (92.5 percent), followed by base rigidity and tumescence activity units (each 90 percent).

Conclusions

The RigiScan Plus software introduced 4 new parameters that facilitate interpretation of the RigiScan data. The new software did not improve the correlation with the final diagnosis compared to the subjective single best event analysis but added new objective parameters, measured and displayed by the software, that facilitate use of the data by the physician.  相似文献   
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We report a case of cervical pregnancy complicated by life threatening hemorrhage. An initial diagnosis of molar pregnancy was made preoperatively. During uterine evacuation she developed profuse hemorrhage which required an emergency hysterectomy for uncontrolled bleeding. Histopathological examination confirmed a cervical pregnancy. The clinical and pathological criteria for the diagnosis and the etiology of cervical pregnancy are discussed.  相似文献   
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Osseodensification is a new method of bone instrumentation for dental implant placement that preserves bulk bone and increases primary implant stability, and may accelerate the implant rehabilitation treatment period and provide higher success and survival rates than conventional methods. The aim of this retrospective study was to evaluate and discuss results obtained on immediate implant placement with immediate and delayed loading protocols under Osseodensification bone instrumentation. This study included private practice patients that required dental implant rehabilitation, between February 2017 and October 2019. All implants were placed under Osseodensification and had to be in function for at least 12 months to be included on the study. A total of 211 implants were included in the study, with a 98.1% total survival rate (97.9% in the maxilla and 98.5% in the mandible). For immediate implants with immediate load, 99.2% survival rate was achieved, and 100% survival rate for immediate implant placement without immediate load cases. A total of four implants were lost during this period, and all of them were lost within two months after placement. Within the limitations of this study, it can be concluded that Osseodensification bone instrumentation provided similar or better results on survival rates than conventional bone instrumentation.  相似文献   
8.
Retinitis pigmentosa (RP) is a group of inherited progressive retinal dystrophies (RD) and is characterized by photoreceptor degeneration. RP is clinically and genetically heterogeneous disorder. More than 70 genes are known and, thus, identification of causative genes and mutations in known genes is challenging. This study was designed to identify the underlying genetic defect in a large extended Saudi family with multiple RP affected members. Fundus photography, Optical Coherence Tomography (OCT) and visual field perimetry were performed for affected individuals. Whole exome sequencing was used to detect the underlying genetic defect in a large family with 12 affected individuals showing autosomal recessive isolated RP. WES data analysis identified a novel insertion mutation in the EYS (eyes shut homolog) gene (c.910_911insT; p.Trp304LeufsTer8). Sanger sequencing validates the variant discovered through exome in all 12 affected individuals and showed that this mutation is segregating with RP phenotype in an autosomal recessive manner in 51 individuals of the family tested here. Our study expands the mutation spectrum of EYS gene in RP patients and extends the body of evidence that supports the importance of EYS gene in eye development.  相似文献   
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