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991.
Objective  A learning health care system (LHS) uses routinely collected data to continuously monitor and improve health care outcomes. Little is reported on the challenges and methods used to implement the analytics underpinning an LHS. Our aim was to systematically review the literature for reports of real-time clinical analytics implementation in digital hospitals and to use these findings to synthesize a conceptual framework for LHS implementation. Methods  Embase, PubMed, and Web of Science databases were searched for clinical analytics derived from electronic health records in adult inpatient and emergency department settings between 2015 and 2021. Evidence was coded from the final study selection that related to (1) dashboard implementation challenges, (2) methods to overcome implementation challenges, and (3) dashboard assessment and impact. The evidences obtained, together with evidence extracted from relevant prior reviews, were mapped to an existing digital health transformation model to derive a conceptual framework for LHS analytics implementation. Results  A total of 238 candidate articles were reviewed and 14 met inclusion criteria. From the selected studies, we extracted 37 implementation challenges and 64 methods employed to overcome such challenges. We identified common approaches for evaluating the implementation of clinical dashboards. Six studies assessed clinical process outcomes and only four studies evaluated patient health outcomes. A conceptual framework for implementing the analytics of an LHS was developed. Conclusion  Health care organizations face diverse challenges when trying to implement real-time data analytics. These challenges have shifted over the past decade. While prior reviews identified fundamental information problems, such as data size and complexity, our review uncovered more postpilot challenges, such as supporting diverse users, workflows, and user-interface screens. Our review identified practical methods to overcome these challenges which have been incorporated into a conceptual framework. It is hoped this framework will support health care organizations deploying near-real-time clinical dashboards and progress toward an LHS.  相似文献   
992.
Understanding the evolutionary history of microbial pathogens is critical for mitigating the impacts of emerging infectious diseases on economically and ecologically important host species. We used a genome resequencing approach to resolve the evolutionary history of an important microbial pathogen, the chytrid Batrachochytrium dendrobatidis (Bd), which has been implicated in amphibian declines worldwide. We sequenced the genomes of 29 isolates of Bd from around the world, with an emphasis on North, Central, and South America because of the devastating effect that Bd has had on amphibian populations in the New World. We found a substantial amount of evolutionary complexity in Bd with deep phylogenetic diversity that predates observed global amphibian declines. By investigating the entire genome, we found that even the most recently evolved Bd clade (termed the global panzootic lineage) contained more genetic variation than previously reported. We also found dramatic differences among isolates and among genomic regions in chromosomal copy number and patterns of heterozygosity, suggesting complex and heterogeneous genome dynamics. Finally, we report evidence for selection acting on the Bd genome, supporting the hypothesis that protease genes are important in evolutionary transitions in this group. Bd is considered an emerging pathogen because of its recent effects on amphibians, but our data indicate that it has a complex evolutionary history that predates recent disease outbreaks. Therefore, it is important to consider the contemporary effects of Bd in a broader evolutionary context and identify specific mechanisms that may have led to shifts in virulence in this system.Emerging infectious diseases (EIDs) pose significant challenges for human health, agricultural crops, and economically and ecologically important populations in nature (14). The incidence of EIDs has been steadily rising over the last several decades (5, 6), and EIDs are of particular concern in an increasingly globalized world. For example, the majority of human EIDs is zoonoses that originate in wildlife (5) and subsequently, create a significant burden for global economies and public health (7, 8). Therefore, scientific efforts to understand and respond to EIDs are critical in diverse fields from biomedicine to conservation biology.Although EIDs result from a complex interplay of factors, many studies focus primarily on the emergence of novel microbial pathogens. There are, in fact, high-profile examples of EIDs caused by the rapid appearance of novel, hypervirulent, or host-switching strains (911), but EIDs are not always caused by rapid or recent evolution of the pathogen itself. Virulence itself is an emergent property of microbe–host–environment interactions (12). Thus, EIDs can result from shifts in any factor—or combination of factors—in the microbe–host–environment epidemiological triangle (13). Characterizing the evolutionary history of emerging pathogens is, thus, critical, allowing us to determine whether observed EIDs result from rapid, recent shifts in organisms with pathogenic potential.Chytridiomycosis is an EID responsible for declines in amphibian species around the world. The chytrid fungus Batrachochytrium dendrobatidis (Bd) was discovered and linked to amphibian declines in 1998 (14, 15). Chytridiomycosis is caused by Bd and kills amphibians by disrupting the integrity of their skin, a physiologically important organ that is involved in gas exchange, electrolyte balance, hydration, and protection from other pathogens (16, 17). Bd infects hundreds of species of amphibians, is found on all continents where amphibians occur, and is responsible for declines and extirpations in a diversity of amphibian hosts (18).Soon after Bd was discovered, researchers proposed two competing hypotheses for the emergence of chytridiomycosis. The emerging pathogen hypothesis posited that a novel disease agent caused chytridiomycosis, and the endemic pathogen hypothesis proposed that an environmental shift disrupted a previously benign microbe–host interaction (19). Over the years, spatiotemporal and genetic data have supported the emerging pathogen hypothesis (reviewed in refs. 20 and 21). Spatiotemporal data provided clear evidence that Bd arrived and spread through geographic regions where it was not present historically (2224). Early genetic studies also found very little genetic differentiation in Bd with no geographic signal, consistent with a recent, rapid spread of a novel disease agent (2527). Recently, genetic and genomic data have been used to describe a geographically widespread Bd lineage [termed the global panzootic lineage (GPL)] (28) and several putatively endemic Bd lineages (2830). However, different studies have used different methods and focused sampling in different parts of the world, precluding integration across studies to determine the evolutionary history leading to the emergence of Bd as a global threat to amphibians.Here, we present whole-genome sequencing from a global panel of Bd isolates to show that Bd has a historically deeper and more complex evolutionary history than previously appreciated. We sequenced Bd genomes from around the world and also, a non-Bd chytrid outgroup that does not attack amphibians [Homolaphlyctis polyrhiza (Hp)] (31). Our focus was primarily on the evolutionary dynamics of Bd in the Americas, because many of the most devastating outbreaks have occurred in the New World. We address outstanding questions about the origins, genetic diversity, and genome structure of Bd that can be resolved using whole-genome data. We also integrate our genomic data with those data from a previous study with complementary geographic sampling (28). Our results reveal that the evolutionary history of Bd is complex, with multiple divergent lineages, heterogeneous patterns of genomic evolution, and no simple link between a single evolutionary event and observed amphibian declines.  相似文献   
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995.
Background/purposeBiodegradable-polymer (BP) and polymer-free (PF) drug eluting stents (DES) were developed to reduce the risk of delayed arterial healing observed with durable-polymer (DP) platforms. Although trials demonstrate BP-DES and PF-DES are non-inferior to DP-DES, there is limited data directly comparing these technologies. We performed a meta-analysis to assess the efficacy and safety of BP-DES versus PF-DES for the treatment of coronary artery disease.Methods/materialsElectronic searches were performed identifying randomized trials comparing BP-DES with PF-DES. Co-primary efficacy endpoints were target vessel revascularization (TVR), target lesion revascularization (TLR) and angiographic in-stent late lumen loss (LLL). Co-secondary safety endpoints were all-cause death, myocardial infarction (MI) and stent thrombosis (ST).ResultsOf 208 studies, 5 met inclusion criteria including 1975 patients. At mean follow-up (14 ± 5 months), BP-DES were associated with significantly reduced rates of TVR (OR 0.58, 95%CI 0.37–0.92, p = 0.02), TLR (4.7% vs 9.5%) (OR 0.48, 95%CI 0.31–0.75, p = 0.001) and in-stent LLL (pooled mean difference ?0.20 mm, 95%CI ?0.24 to ?0.16, p < 0.001). There was no difference in safety, including all-cause death (OR 1.24, 95%CI 0.68–2.28, p = 0.48), MI (OR 0.92, 95%CI 0.54–1.56, p = 0.75) or ST (OR 1.58, 95%CI 0.67–3.73, p = 0.30).ConclusionsThese data suggests that BP-DES are more efficacious when compared with PF-DES for the treatment of CAD.  相似文献   
996.
997.
AIDS and Behavior - Little is known about the intersection of HIV stigma and substance use stigma. Using data from 188 HIV-positive people who inject drugs (PWID) in Russia, we examined the...  相似文献   
998.

Background

Medial unicompartmental knee arthroplasty (UKA) may have advantages over total knee arthroplasty (TKA) in the setting of obesity. There has been no direct comparison between the two cohorts. This study compares outcomes and complications of severely obese patients undergoing medial UKA versus TKA.

Methods

Six hundred and fifty medial UKA and 1300 TKA were performed in patients with BMI > 35 kg/m2 (mean 41 kg/m2) between 2007 and 2012. Pre- and postoperative ROM, Knee Society scores, perioperative factors, complications and reoperations were compared.

Results

UKA patients had higher preoperative ROM, and Knee Society pain (KSP), functional (KSF), and clinical (KSC) scores (p < 0.001, p = 0.0008, p = 0.0003, p = 0.051 respectively). Mean tourniquet times, operative times, and lengths of stay were lower after UKA. Four TKA patients required transfusion. Mean follow-up was 2.3 years. The frequency of manipulation under anesthesia was higher in TKA patients (p < 0.001), while the rate of component revision was similar between the two groups (1.2% vs. 1.7%, p = 0.328). Frequency of deep infection was lower in the UKA group (p = 0.016). Postoperative KSF, change in KSF, and ROM were higher (p < 0.0001) after UKA, but KSP and KSC were equivalent.

Conclusions

Severely obese patients who underwent medial UKA demonstrated equal survivorship with substantially fewer reoperations, reduced deep infection, and less perioperative complications at short term follow-up. Severely obese patients had improved KSF scores and maintenance of ROM after UKA compared with TKA.  相似文献   
999.
1000.

Background

We evaluated the repeatability of the calculation of myocardial blood flow (MBF) at rest and pharmacological stress, and calculated the coronary flow reserve (CFR) utilizing 82Rb PET imaging. The aim of the research was to prove high repeatability for global MBF and CFR values and good repeatability for regional MBF and CFR values. The results will have significant impact on cardiac PET imaging in terms of making it more affordable and increasing its use.

Methods

12 normal volunteers were imaged at rest and during pharmacological stress, with 2220 MBq of 82Rb each. A GE Advance PET system was used to acquire dynamic 50-frame studies. MBF was calculated with a 2-compartmental model using a modified PMOD program (PMOD; University Hospital Zurich, Zurich, Switzerland). Two differential equations, describing a 2-compartmental model, were solved by numerical integration and using Levenberg-Marquardt's method for fitting data. The PMOD program defines 16 standard segments and calculates myocardial flow for each segment, as well as average septal, anterior, lateral, inferior and global flow. Repeatability was evaluated according to the method of Bland and Altman.

Results

Global rest and stress MBF, as well as global CFR, showed very good repeatability. No significant differences were found between the paired resting global MBF (0.63 ± 0.13 vs. 0.64 ± 0.13 mL/min/g; mean difference, -1.0% ± 2.6%) and the stress global MBF (1.37 ± 0.23 vs. 1.37 ± 0.24; mean difference, 0.1% ± 2.3%). Global CFR was highly reproducible (2.25 ± 0.56 vs. 2.22 ± 0.54, P = not statistically significant; mean difference, 1.3% ± 14.3%). Repeatability coefficients for global rest MBF were 0.033 (5.2%) and stress MBF 0.062 (4.5%) mL/min/g. Regional rest and stress MBF and CFR have shown good reproducibility. The average per sector repeatability coefficients for rest MBF were 0.056 (8.5%) and stress MBF 0.089 (6.3%) mL/min/g, and average repeatability coefficient for CFR was 0.25 (10.6%).

Conclusion

The results of the study show that software calculation of MBF and CFR with 82Rb myocardial PET imaging is highly repeatable for global values and has good repeatability for regional values.  相似文献   
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