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We evaluated the efficacy of a peer-educator network intervention as a strategy to reduce HIV acquisition among injection drug users (IDUs) and their drug and/or sexual networks. A randomized controlled trial was conducted in St. Petersburg, Russia among IDU index participants and their risk network participants. Network units were randomized to the control or experimental intervention. Only the experimental index participants received training sessions to communicate risk reduction techniques to their network members. Analysis includes 76 index and 84 network participants who were HIV uninfected. The main outcome measure was HIV sero-conversion. The incidence rates in the control and experimental groups were 19.57 (95 % CI 10.74–35.65) and 7.76 (95 % CI 3.51–17.19) cases per 100 p/y, respectively. The IRR was 0.41 (95 % CI 0.15–1.08) without a statistically significant difference between the two groups (log rank test statistic X2 = 2.73, permutation p value = 0.16). Retention rate was 67 % with a third of the loss due to incarceration or death. The results show a promising trend that this strategy would be successful in reducing the acquisition of HIV among IDUs.  相似文献   
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ObjectiveWe aimed to iteratively refine an implementation model for managing cloud-based longitudinal care plans (LCPs) for children with medical complexity (CMC).Materials and MethodsWe conducted iterative 1-on-1 design sessions with CMC caregivers (ie, parents/legal guardians) and providers between August 2017 and March 2019. During audio-recorded sessions, we asked participants to walk through role-specific scenarios of how they would create, review, and edit an LCP using a cloud-based prototype, which we concurrently developed. Between sessions, we reviewed audio recordings to identify strategies that would mitigate barriers that participants reported relating to 4 processes for managing LCPs: (1) taking ownership, (2) sharing, (3) reviewing, and (4) editing. Analysis informed iterative implementation model revisions.ResultsWe conducted 30 design sessions, with 10 caregivers and 20 providers. Participants emphasized that cloud-based LCPs required a team of owners: the caregiver(s), a caregiver-designated clinician, and a care coordinator. Permission settings would need to include universal accessibility for emergency providers, team-level permission options, and some editing restrictions for caregivers. Notifications to review and edit the LCP should be sent to team members before and after clinic visits and after hospital encounters. Mitigating double documentation barriers would require alignment of data fields between the LCP and electronic health record to maximize interoperability.DiscussionThese findings provide a model for how we may leverage emerging Health Insurance Portability and Accountability Act–compliant cloud computing technologies to support families and providers in comanaging health information for CMC.ConclusionsUtilizing these management strategies when implementing cloud-based LCPs has the potential to improve team-based care across settings.  相似文献   
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BACKGROUND: The aim of the study was to derive a donor arm disinfection technique that was rapid, but with a disinfection efficacy equivalent to a previous "best-practice" technique. This method consisted of a two-stage procedure with an initial application of 70% isopropyl alcohol and then 2% tincture of iodine (IATI). The total time for the IATI method was 2 minutes in duration. A rapid technique (1 min in duration) was needed to obviate potential problems due to increased donor waiting time, had the IATI method been implemented at blood donation sessions.
STUDY DESIGN AND METHODS: A direct swabbing and plating technique was used to enumerate bacteria present before and after disinfection. In total, seven methods were evaluated.
RESULTS: The chlorhexidine/alcohol applicator (CAA) disinfection device containing 1.5 mL of 2% chlorhexidine gluconate and 70% isopropyl alcohol (99.91% reduction; confidence limits, 99.55%, 99.98%) was shown to have equivalent disinfection efficacy as the IATI method (99.89% reduction; confidence limits, 99.36%, 99.98%; p = 0.86). Procedural time for the 1.5-mL CAA method was 1 minute thereby avoiding potential problems of increased donor waiting time, inherent in the IATI 2-minute procedure at blood donation sessions.
CONCLUSIONS: The 1.5-mL CAA disinfection method offers blood services a rapid and effective donor arm disinfection procedure. In 2006, the 1.5-mL CAA procedure was implemented throughout the entire English blood service for all donations.  相似文献   
998.
X-ray fluorescence tomography promises to map elemental distributions in unstained and unfixed biological specimens in three dimensions at high resolution and sensitivity, offering unparalleled insight in medical, biological, and environmental sciences. X-ray fluorescence tomography of biological specimens has been viewed as impractical—and perhaps even impossible for routine application—due to the large time required for scanning tomography and significant radiation dose delivered to the specimen during the imaging process. Here, we demonstrate submicron resolution X-ray fluorescence tomography of a whole unstained biological specimen, quantifying three-dimensional distributions of the elements Si, P, S, Cl, K, Ca, Mn, Fe, Cu, and Zn in the freshwater diatom Cyclotella meneghiniana with 400-nm resolution, improving the spatial resolution by over an order of magnitude. The resulting maps faithfully reproduce cellular structure revealing unexpected patterns that may elucidate the role of metals in diatom biology and of diatoms in global element cycles. With anticipated improvements in data acquisition and detector sensitivity, such measurements could become routine in the near future.  相似文献   
999.
Kelly AS, Jacobs DR Jr, Sinaiko AR, Moran A, Steffen LM, Steinberger J. Relation of circulating oxidized LDL to obesity and insulin resistance in children. Introduction: Circulating oxidized low‐density lipoprotein (LDL), a marker of oxidative stress, is associated with obesity, insulin resistance, metabolic syndrome, and cardiovascular disease in adults. However, little is known about its relation to insulin resistance and cardiovascular risk factors in children. The purpose of this study was to assess the relation of oxidative stress, measured by circulating oxidized LDL, with measures of adiposity and insulin resistance in children. Methods: Oxidized LDL, measures of body fatness (body mass index: BMI, percent body fat, waist circumference, percent trunk fat, abdominal visceral and subcutaneous fat), insulin resistance with euglycemic insulin clamp (Mlbm), blood pressure, and blood lipids were obtained in 78 children. Oxidized LDL was compared between normal weight children (BMI < 85th percentile) and overweight/obese children (BMI ≥ 85th percentile) and levels were evaluated for associations with body fatness and insulin resistance. Results: Oxidized LDL levels were significantly higher in overweight/obese vs. normal weight children (p < 0.0001). Oxidized LDL was significantly correlated with BMI, percent body fat, waist circumference, percent trunk fat, abdominal visceral fat, and abdominal subcutaneous fat (all p‐values <0.0001). Moreover, oxidized LDL was negatively correlated with Mlbm, even after adjustment for adiposity (p < 0.01). Conclusions: Oxidized LDL is significantly associated with adiposity and with insulin resistance, independent of body fatness, in children. Oxidative stress may be independently related to the development of insulin resistance early in life, especially in obese youth.  相似文献   
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The antiphospholipid syndrome (APS) is an autoimmune disease characterized by thrombosis, recurrent fetal loss, and the presence of antiphospholipid antibodies (aPL). Recent data support the idea that the thrombotic activity in APS patients is attributed to enhanced cytokine release via activation of certain Toll-like receptors. To investigate these mechanisms more precisely, different experimental approaches were used to investigate this connection in detail. IgG fractions and/or monoclonal aPL, either generated from murine or human B cells were intensely used for stimulation experiments of monocytes, endothelial cells, or dendritic cells. All these stimuli induced an enhanced expression and secretion of cytokines, especially tumor necrosis factor (TNF)-α, caused by specific regulation or activation of Toll-like receptors. Using specific agonists or inhibitors could confirm the causal connection of these stimulatory effects. This review focuses on these recent developments, connecting the binding of aPL with the activity of Toll-like receptors, especially in monocytes, endothelial cells, and dendritic cells.  相似文献   
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