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During the wet season of 2010, yellow fever virus (YFV) was detected in field-collected mosquitoes in the Kédougou region in southeastern Senegal. During this outbreak, we studied the association of the abundance of YFV-infected mosquitoes and land cover features to try and understand the dynamics of YFV transmission within the region. In total, 41,234 mosquito females were collected and tested for virus infection in 5,152 pools. YFV was detected in 67 pools; species including Aedes furcifer (52.2% of the infected pools), Ae. luteocephalus (31.3% of the infected pools), Ae. taylori (6.0% of the infected pools) and six other species (10.4% of the infected pools) captured in September (13.4%), October (70.1%), and November (16.4%). Spatially, YFV was detected from mosquitoes collected in all land cover classes but mainly, forest canopies (49.2%). Human infection is likely mediated by Ae. furcifer, the only species found infected with YFV within villages. Villages containing YFV-infected mosquitoes were significantly closer to large forests (> 2 ha) than villages in which no infected mosquitoes were detected.  相似文献   
63.

Aims/hypothesis

White cell count has been shown to predict incident type 2 diabetes, but differential white cell count has received scant attention. We examined the risk of developing diabetes associated with differential white cell count and neutrophil:lymphocyte ratio and the effect of insulin sensitivity and subclinical inflammation on white cell associations.

Methods

Incident diabetes was ascertained in 866 participants aged 40–69 years in the Insulin Resistance Atherosclerosis Study after a 5 year follow-up period. The insulin sensitivity index (SI) was measured by the frequently sampled IVGTT.

Results

C-reactive protein was directly and independently associated with neutrophil (p?<?0.001) and monocyte counts (p?<?0.01) and neutrophil:lymphocyte ratio (p?<?0.001), whereas SI was inversely and independently related to lymphocyte count (p?<?0.05). There were 138 (15.9%) incident cases of diabetes. Demographically adjusted ORs for incident diabetes, comparing the top and bottom tertiles of white cell (1.80 [95% CI 1.10, 2.92]), neutrophil (1.67 [1.04, 2.71]) and lymphocyte counts (2.30 [1.41, 3.76]), were statistically significant. No association was demonstrated for monocyte count (1.18 [0.73, 1.90]) or neutrophil:lymphocyte ratio (0.89 [0.55, 1.45]). White cell and neutrophil associations were no longer significant after further adjusting for family history of diabetes, fasting glucose and smoking, but the OR comparing the top and bottom tertiles of lymphocyte count remained significant (1.96 [1.13, 3.37]). This last relationship was better explained by SI rather than C-reactive protein.

Conclusions/interpretation

A lymphocyte association with incident diabetes, which was the strongest association among the major white cell types, was partially explained by insulin sensitivity rather than subclinical inflammation.  相似文献   
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Context: Recent studies on the mechanism of action (MOA) of bone-active drugs have rekindled interest in how to present and interpret dynamic histomorphometric parameters of bone remodeling. Objective: We compared the effects of an established anabolic agent, teriparatide (TPTD), with those of a prototypical antiresorptive agent, zoledronic acid (ZOL). Design: This was a 12-month, randomized, double-blind, active-comparator controlled, cross-sectional biopsy study. Setting: The study was conducted at 12 U.S. and Canadian centers. Subjects: Healthy postmenopausal women with osteoporosis participated in the study. Interventions: Subjects received TPTD 20 μg once daily by sc injection (n = 34) or ZOL 5 mg by iv infusion at baseline (n = 35). Main Outcome Measures: The primary end point was mineralizing surface/bone surface (MS/BS), a dynamic measure of bone formation, at month 6. A standard panel of dynamic and static histomorphometric indices was also assessed. When specimens with missing labels were encountered, several methods were used to calculate mineral apposition rate (MAR). Serum markers of bone turnover were also measured. Results: Among 58 subjects with evaluable biopsies (TPTD = 28; ZOL = 30), MS/BS was significantly higher in the TPTD group (median: 5.60 vs. 0.16%, P < 0.001). Other bone formation indices, including MAR, were also higher in the TPTD group (P < 0.05). TPTD significantly increased procollagen type 1 N-terminal propeptide (PINP) at months 1, 3, 6, and 12 and carboxyterminal cross-linking telopeptide of collagen type 1 (CTX) from months 3 to 12. ZOL significantly decreased PINP and CTX below baseline at all time points. Conclusions: TPTD and ZOL possess fundamentally different mechanisms of action with opposite effects on bone formation based on this analysis of both histomorphometric data and serum markers of bone formation and resorption. An important mechanistic difference was a substantially higher MS/BS in the TPTD group. Overall, these results define the dynamic histomorphometric characteristics of anabolic activity relative to antiresorptive activity after treatment with these two drugs.  相似文献   
66.
BackgroundMost vertebral compression fractures are not recognized or treated. We conducted a controlled trial in older patients with vertebral fractures incidentally reported on chest radiographs, comparing usual care with osteoporosis interventions directed at physicians (opinion-leader-endorsed evidence summaries and reminders) or physicians+patients (adding activation with leaflets and telephone counseling).MethodsPatients aged >60 years who were discharged home from emergency departments and who had vertebral fractures reported but were not treated for osteoporosis were allocated to usual care (control) or physician intervention using alternate-week time series. After 3 months, untreated controls were re-allocated to physician+patient intervention. Allocation was concealed, outcomes ascertainment blinded, and analyses intent-to-treat. Primary outcome was starting osteoporosis treatment within 3 months.ResultsThere were 1315 consecutive patients screened, and 240 allocated to control (n = 123) or physician intervention (n = 117). Groups were similar at baseline (average age 74 years, 45% female, 58% previous fractures). Compared with controls, physician interventions significantly (all P <.001) increased osteoporosis treatment (20 [17%] vs 2 [2%]), bone mineral density testing (51 [44%] vs 5 [4%]), and bone mineral density testing or treatment (57 [49%] vs 7 [6%]). Three months after controls were re-allocated to physician+patient interventions, 22% had started treatment and 65% had bone mineral density testing or treatment (P <.001 vs controls). Physician+patient interventions increased bone mineral density testing or treatment an additional 16% compared with physician interventions (P = .01).ConclusionsAn opinion-leader-based intervention targeting physicians substantially improved rates of bone mineral density testing and osteoporosis treatment in patients with incidental vertebral fractures, compared with usual care. Even better osteoporosis management was achieved by adding patient activation to physician interventions [NCT00388908].  相似文献   
67.

Background

The purpose of the study is to review the CT findings associated with ventriculostomy placement in regards to the safety of an EVD plus recombinant tissue plasminogen activator (rt-PA) for IVH.

Methods

A retrospective review was conducted for patients receiving intraventricular rt-PA for IVH from January 2004 to September 2009. Safety was assessed by the presence of EVD tract hemorrhage by CT at baseline after EVD placement, worsening hemorrhage after rt-PA, and CSF infection. IVH volumetrics were assessed by the Le Roux score and outcomes by Glasgow Outcome Scale and modified Rankin Scale.

Results

Twenty-seven patients received rt-PA for IVH. Median dose was 2 mg (range 0.3–8) and a median of two doses (range 1–17) were given. Worsening EVD catheter tract hemorrhage after rt-PA was 46.7 %, with a significantly higher incidence of worsening tract hemorrhage seen with incorrectly placed EVDs (p = 0.04). IVH hematoma burden decreased by a median Le Roux score of 10 (range 3–16) prior to rt-PA to 4 (range 0–16) after rt-PA. There were no central nervous system bacterial infections.

Conclusion

Intraventricular rt-PA appears to be relatively safe especially when all EVD fenestrations are within the ventricle and reduces IVH burden similar to other studies. We describe a CT-based EVD tract hemorrhage grading scale to evaluate EVD tract hemorrhage before and after thrombolysis, and a bone-window technique to evaluate EVD fenestrations prior to IVH thrombolysis. Further research is needed evaluating these imaging techniques in regard to intraventricular thrombolytic safety and EVD tract hemorrhage.  相似文献   
68.
Human papillomavirus (HPV) infections have received considerable attention in recent years. Of the 120 or so known types of the virus, some cause a variety of benign wart‐like lesions of the skin and genital and oral mucosae, whilst others are aetiologically associated with cervical and anogenital cancers. Recent epidemiologic evidence suggests that HPV may also be an independent risk factor for oropharyngeal cancer. In this context it has been suggested that HPV virus may modulate the process of carcinogenesis in some tobacco and alcohol induced oropharyngeal cancers and act as the primary oncogenic agent for inducing carcinogenesis among non‐smokers. Dental practitioners have a major role in detecting all lesions of the oral mucosa caused, or possibly caused, by HPV. This paper briefly reviews the current state of knowledge of molecular and clinical aspects of HPV infections of the oral mucosa.  相似文献   
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