Effect of gender on the reliability of COVID-19 rapid antigen test among elderly

Defining con-founders that affect the reliability of diagnostic tests for coronavirus disease 2019 is vital to breaking the chain of infection. The elderly population is a higher risk group for the emerging virus. However, gender seems to exert a critical role in modifying the infection risk among women owing to hormonal changes. The menopause transition is an exceptional period for older women where the protective and immunomodulatory effects of the estrogen hormone are lost. Accordingly, attention should be given to postmenopausal women since they will have an increased risk compared to their pre-menopausal peers.     

Performance of the new FilmArray Blood Culture Identification 2 panel and its potential impact on clinical use in patients with Gram-negative bacteremia

IntroductionRapid diagnostic tests have been developed recently for rapid species or resistance genes identification, offering the potential to improve the selection of appropriate antibiotics. The newly developed FilmArray Blood Culture Identification 2 (BCID2) panel, which can identify more species and resistance genes, such as extended-spectrum beta-lactamase, is expected to make an impact on antimicrobial practice.MethodsThe consecutive 50 inpatients with Gram-negative bacilli bacteremia were enrolled to this retrospective single-center study. In addition to the existing FilmArray Blood Culture Identification (BCID) panel, we have implemented BCID2 panel for positive blood culture. The sensitivity and specificity of BCID and BCID2 panel were respectively calculated, and a simulation study of time to effective, optimal and de-escalation therapy was performed based on BCID or BCID2 result.ResultsA total of 52 Gram-negative organisms in 50 patients were identified from blood cultures. Of these, 45 (87%) organisms were detected by BCID2 panel, which was more than BCID panel (41 organisms, 79%). BCID2 panel detected 5 CTX-M genes, which were concordant with conventional method. The time to effective therapy did not differ between BCID arm and BCID2 arm; however, the median time to optimal therapy (34 h in BCID arm and 26 h in BCID2 arm, P = 0.0007) and the median time to de-escalation therapy (42 h in BCID arm and 22 h in BCID2 arm, P = 0.0005) were significantly shortened.ConclusionsThis simulation study of BCID2 panel showed high sensitivity and specificity, and the potential impact on shortening the time to optimal and de-escalation therapy.     

A Review of Aerosol Generation Mitigation in International Dental Guidance

IntroductionThe coronavirus disease 2019 (COVID-19) led to the worldwide closure of dental practices or reduction of dental services. By the end of April 2020, governments and professional organisations were publishing recommendations or guidance for the reopening/restructuring of dental services. The aim of this study was to assess how dental aerosol-generating procedures (AGPs) were defined in international dental guidelines, what mitigation processes were advised, and whether they were linked to COVID-19 epidemiology.MethodsElectronic searches of a broad range of databases, along with grey literature searches, without language restriction were conducted up to 13 July 2020. Recommendations for the use of face masks and fallow times with patients without COVID-19 were assessed against the deaths per 1 million population in the included countries and country income level using Pearson Chi-squared statistics.ResultsSixty-three guidance documents were included. Most (98%) indicated that AGPs can be performed with patients without COVID-19 with caveats, including advice to restrict AGPs where possible, with 21% only recommending AGPs for dental emergencies. Face masks were recommended by most documents (94%), with 91% also specifying the use of goggles or face shields. Fallow periods for patients without COVID-19 were mentioned in 48% of documents, ranging from 2 to 180 minutes. There were no significant differences in recommendations for face masks or fallow time in patients without COVID-19 by country death rate (P = .463 and P = .901) or World Bank status (P = .504 and P = .835). Most documents recommended procedural or environmental mitigations such as preprocedural mouthwash (82%) and general ventilation (52%). Few documents provided underpinning evidence for their recommendations.ConclusionsWhile the amount of high-quality direct evidence related to dentistry and COVID-19 remains limited, it is important to be explicit about the considered judgements for recommendations as well as generate new evidence to face this challenge.     

个体化假体复合组织工程技术修复兔下颌骨缺损

目的研究快速成型（RP）技术辅助下制作的个体化假体复合珊瑚羟基磷灰石（CHA）、重组人骨形成蛋白2（rhBMP-2）修复兔下颌骨缺损的成骨效果。 方法以27只新西兰大白兔为实验对象，随机数字表法平均分成3组（每组9只），全部建立下颌骨连续性缺损模型，并在兔下颌骨缺损区分别植入个体化假体+自体骨（A组）、个体化假体+CHA（B组）、个体化假体+CHA+rhBMP-2（C组）。分别于术后4、12、24周3个时间点处死动物取材，进行大体标本观察，以及骨钙素（OC）、Ⅰ型胶原（COL-1）的免疫组化观察，分别比较各组修复骨缺损的能力，并对实验数据进行重复测量设计资料的单因素方差分析。 结果术后24周各组实验兔外形均对称，通过OC及COL-1的吸光度检测，骨缺损区均有大量新骨形成，A组（0.537 ± 0.010）、C组（0.530 ± 0.010）可见大量骨小梁及编织骨结构，缺损区的新骨OC、COL-1的免疫组化观察基本一致，差异无统计学意义（t = 0.007，P>0.05）；但A组强于B组（0.415 ± 0.009，t = 0.122，P<0.001）；C组也强于B组（t = 0.121，P<0.001），差异均有统计学意义。 结论在兔下颌骨缺损修复中，通过RP技术和组织工程技术相结合，CHA复合rhBMP-2后成骨能力明显增强，成骨效能肯定，为后期的临床应用提供可靠的实验基础。     

Developmental validation of the Huaxia™ Platinum PCR amplification kit: A 6-dye multiplex direct amplification assay designed for Chinese reference samples

The Huaxia™ Platinum Kit for short tandem repeat (STR) amplification was designed to meet the needs of the rapidly growing Chinese forensic database. This PCR multiplex allows simultaneous amplification of the following autosomal loci: D3S1358, vWA, D16S539, CSF1PO, TPOX, D8S1179, D21S11, D18S51, Penta E, D2S441, D19S433, TH01, FGA, D22S1045, D5S818, D13S317, D7S820, D6S1043, D10S1248, D1S1656, D12S391, D2S1338, Penta D and the gender-identification markers Yindel, and AMEL.The Huaxia™ Platinum Kit enables direct amplification from blood and buccal samples stored on treated and untreated paper, and features an optimized PCR protocol that yields time to results in less than 45 min. Developmental validation testing followed SWGDAM guidelines and demonstrated that this assay produces reproducible and accurate results. Studies on 798 individuals in 4 major Chinese ethnic groups produced highly concordant results with other commercially available STR genotyping kits. The validation results demonstrate that the Huaxia™ Platinum Kit is a robust and reliable identification system for forensic DNA databasing applications.