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31.
The FilmArray Blood Culture Identification Panel was validated for nonblood sterile site specimens with clinical impact of rapid identification compared to conventional diagnostics. The panel accurately identified target organisms from 98% of positive broth cultures a median 1.1?day faster than conventional techniques (P?<?0.0001) with potential clinical impact in 22% of cases.  相似文献   
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Background

Whether prolonged operative time is an independent risk factor for subsequent surgical site infection (SSI) and periprosthetic joint infection (PJI) following total joint arthroplasty (TJA) remains a clinically significant and underexplored issue. The aim of this study is to investigate the association between operative time and the risk of subsequent SSI and PJI in patients undergoing primary TJA.

Methods

We retrospectively reviewed 17,342 primary unilateral total knee arthroplasty and total hip arthroplasty performed at a single institution between 2005 and 2016, with a minimum follow-up of 1 year. A multivariate logistic regression model was conducted to identify the association between operative time and the development of SSI within 90 days and PJI within 1 year.

Results

Overall, the incidence of 90-day SSI and 1-year PJI was 1.2% and 0.8%, respectively. Patients with an operative time of >90 minutes had a significantly higher incidence of SSI and PJI (2.1% and 1.4%, respectively) compared to cases lasting between 60 and 90 minutes (1.1% and 0.7%), and those lasting ≤60 minutes (0.9% and 0.7%, P < .01). In the multivariate model, the risk for infection increased by an odds ratio of 1.346 (95% confidential interval 1.114-1.627) for 90-day SSI and 1.253 (95% confidential interval 1.060-1.481) for 1-year PJI for each 20-minute increase in operative time.

Conclusion

In patients undergoing primary TJA, each 20-minute increase in operative time was associated with nearly a 25% increased risk of subsequent PJI. We advocate that surgeons pay close attention to this underappreciated risk factor while maintaining safe operative practices, which minimize unnecessary steps and wasted time in the operating room.  相似文献   
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Although sphingomyelins known to be are lipid constituents of the plasma membrane in vertebrates, much remains obscure about the metabolism of sphingomyelins in insects. With ultra performance liquid chromatography‐time‐of‐flight‐tandem mass spectrometry analysis, we revealed for the first time that sphingomyelins are abundant in Nilaparvata lugens (Stål), the brown planthopper (BPH), and their biosynthesis is carried out by sphingomyelin synthase‐like protein 2 (SMSL2), which is homologous to sphingomyelin synthase‐related protein (SMSr). Unlike other insect species, high concentrations of sphingomyelins rather than ceramide phosphoethanolamines exist in the BPH. Two putative genes, which are homologous to SMSr, are named Nilaparvata lugens SMS‐like 1 (NlSMSL1) and 2 (NlSMSL2). Knockdowns of both NlSMSL2 and NlSMSL1 were conducted but only the first decreased concentrations of sphingomyelins in the BPH, indicating that NlSMSL2 plays a role in the biosynthesis of sphingomyelins. Real‐time quantitative PCR analysis revealed both NlSMSL1 and NlSMSL2 are highly expressed in BPH adults, with NlSMSL1 specifically highly expressed in reproductive organs (ovaries and testes) whereas NlSMSL2 was highly expressed in the malpighian tubules. The knockdown of NlSMSL1 or NlSMSL2 increased BPH female body weight but not that of males, suggesting sex‐specific roles for SMSLs in influencing BPH body weight. The results suggest that NlSMSL2 catalyses the synthesis of sphingomyelins and maintains female BPH body weight through alteration of sphingolipid content.  相似文献   
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TitlePrevalence and Risk Factors for Hypertrophic Scarring of Split Thickness Autograft Donor Sites in a Pediatric Burn Population.ObjectiveThe split-thickness autograft remains a fundamental treatment for burn injuries; however, donor sites may remain hypersensitive, hyperemic, less pliable, and develop hypertrophic scarring. This study sought to assess the long-term scarring of donor sites after pediatric burns.MethodsA retrospective review of pediatric burn patients treated at a single institution (2010–2016) was performed. Primary outcomes were prevalence of donor site hypertrophic scarring, scarring time course, and risk factor assessment.Results237 pediatric burn patients were identified. Mean age at burn was 7 yrs., mean %TBSA was 26% with 17% being Full Thickness. Mean follow-up was 2.4 yrs. Hypertrophic scarring was observed in 152 (64%) patients with 81 (34%) patients having persistent hypertrophic scarring through long-term follow-up. Patient-specific risk factors for hypertrophic scarring were Hispanic ethnicity (P = 0.03), increased %TBSA (P = 0.03), %Full Thickness burn (P = 0.02) and total autograft amount (P = 0.03). Donor site factors for hypertrophic scarring were longer time to epithelialization (P < 0.0001), increased donor site harvest depth (P < 0.0001), autografts harvested in the acute burn setting (P = 0.008), and thigh donor site location (vs. all other sites; P < 0.0001). The scalp, arm, foot, and lower leg donor sites (vs. all other sites) were less likely to develop HTS (P < 0.0001, 0.02, 0.005, 0.002, respectively), along with a history of previous donor site harvest (P = 0.04).ConclusionsHypertrophic scarring is a prominent burden in donor site wounds of pediatric burn patients. Knowledge of pertinent risk factors can assist with guiding management and expectations.  相似文献   
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ABSTRACT

Background: Gene editing has shown huge potential in correcting aberrant splicing and Cas13 has been identified as being particularly suitable for targeting RNA. It has therefore become increasingly important to highlight new splice site mutations that may be correctable, particularly in genes that are too large to be encoded by AAV vectors. About 20% of Usher Type 1 cases are caused by mutations in CDH23.

Purpose: To report a novel splice site mutation of CDH23 associated with Usher Type 1D.

Materials and Methods: Case report.

Results: A 35-year-old Caucasian female who is congenitally deaf with vestibular dysfunction presented with visual acuity of 6/12 in both eyes. Fundus examination revealed findings typical of retinitis pigmentosa with foveal preservation of photoreceptor layer. Next generation sequencing analysis revealed a novel homozygous variant, c.9319 + 1G>T in CDH23 consistent with the diagnosis of Usher Syndrome Type 1D. The c.9319 + 1G>T variant is predicted to affect splicing at the exon 65/intron 65 boundary, which highly likely leads to complete skipping of exon 65.

Conclusions: We describe a case of a typical Usher Syndrome Type 1D caused by a novel splice site variant in CDH23. Currently there are no treatments for CDH23 related retinal degeneration, partly because the cDNA size of 10kb is too large for AAV vector gene augmentation therapy. Alternative strategies include CRISPR-Cas9 adenine base editors and RNA editing with CRISPR-Cas13. Single-nucleotide editing represents a promising approach for targeting this variant in CDH23 to restore the wildtype splice donor site at this position.  相似文献   
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