Identifying and Remediating Super-splasher Sinks to Reduce Dispersal of Pathogens From Sink Drains.

Testing for dispersal of fluorescent gel from sink drains was sensitive for detection of sinks that dispersed gram-negative bacilli outside the bowl. Reducing the flow rate of sinks with rapid water inflow and/or elimination of obstruction leading to slow outflow was effective in preventing dispersal of fluorescence and gram-negative bacilli.

Systemic therapy in children and adolescents with mental disorders: a systematic review and meta-analysis.

BACKGROUND: Systemic therapy (ST) is a psychotherapeutic intervention in complex human systems (both psychological and interpersonal). Cognitive behavioural therapy (CBT) is an established treatment for children and adolescents with mental disorders. As methodologically rigorous systematic reviews on ST in this population are lacking, we conducted a systematic review and meta-analysis to compare the benefit and harm of ST (and ST as an add-on to CBT) with CBT in children and adolescents with mental disorders. METHODS: We searched MEDLINE, Embase, PsycINFO and other sources for randomised controlled trials in 14 mental disorder classes for the above comparisons in respect of effects on patient-relevant outcomes (search date: 7/2022). Where possible, meta-analyses were performed and results were graded into 3 different evidence categories: "proof", "indication", or "hint" (or none of these categories). PRISMA standards were followed. RESULTS: Fifteen studies in 5 mental disorder classes with usable data were identified. 2079 patients (mean age: 10 to 19 years) were analysed. 12/15 studies and 29/30 outcomes showed a high risk of bias. In 2 classes, statistically significant and clinically relevant effects in favour of ST were found, supporting the conclusion of a hint of greater benefit of ST for mental and behavioural disorders due to psychoactive substance use and of ST as an add-on to CBT for obsessive-compulsive disorders. In 2 other classes (eating disorders; hyperkinetic disorders), there was no evidence of greater benefit or harm of ST. For affective disorders, a statistically significant effect to the disadvantage of ST was found for 1 outcome, supporting the conclusion of a hint of lesser benefit of ST. CONCLUSIONS: Our results show a hint of greater benefit of ST (or ST as an add-on to CBT) compared with CBT for 2 mental disorder classes in children and adolescents (mental and behavioural disorders due to psychoactive substance use, obsessive compulsive disorders). Given the importance of CBT as a control intervention, ST can therefore be considered a beneficial treatment option for children and adolescents with certain mental disorders. Limitations include an overall high risk of bias of studies and outcomes and a lack of data for several disorders.

Carbon Dioxide Monitoring Demonstrates Variations in the Quality of Ventilation on Public Transportation Buses and University Student Shuttle Vans and Identifies Effective Interventions.

Background: There is a risk for transmission of severe acute respiratory syndrome 2 (SARS-CoV-2) and other respiratory viruses in motor vehicles, particularly if ventilation is inadequate. Methods: We used carbon dioxide monitoring to examine the quality of ventilation in several public transportation buses and in university student shuttle vans in the Cleveland metro area during peak and non-peak travel times. Carbon dioxide levels above 800 parts per million (ppm) were considered an indicator of suboptimal ventilation for the number of people present. In the shuttle vans, we evaluated the impact of an intervention to improve ventilation. Results: In large articulated buses with 2 ventilation systems, carbon dioxide concentrations never exceeded 800 ppm, whereas in standard buses with 1 ventilation system concentrations rose above 800 ppm during peak travel times and on some trips during non-peak travel times. In shuttle vans, the ventilation system was not turned on during routine operation, and carbon dioxide levels rose above 800 ppm on all trips during peak and non-peak travel times. In the shuttle vans, an intervention involving operation of the existing ventilation system resulted in a significant reduction in carbon dioxide levels (mean concentration, 1,042 no intervention versus 785 with intervention; P < 0.001). Conclusions: Our findings demonstrate substantial variability in the quality of ventilation in public transportation buses and university shuttle vans. There is a need for efforts to assess and optimize ventilation in motor vehicles used for public transportation to reduce the risk for aerosol-mediated transmission of respiratory viruses. Carbon dioxide monitoring may provide a useful tool to assess and improve ventilation.

UK robotic arthroplasty clinical and cost effectiveness randomised controlled trial for hips (RACER-Hip): a study protocol.

INTRODUCTION: The number of robotic-assisted hip replacement procedures has expanded globally with the intended aim of improving outcomes. Intraoperative robotic-arm systems add additional costs to total hip replacement (THR) surgery but may improve surgical precision and could contribute to diminished pain and improved function. Additionally, these systems may reduce the need for expensive revision surgery. Surgery with conventional instruments may be just as successful, quick and affordable. There is timely demand for a robust evaluation of this technology. METHODS AND ANALYSIS: The Robotic Arthroplasty Clinical and cost Effectiveness Randomised controlled trial for Hips (RACER-Hip) is a multicentre (minimum of six UK sites), participant-assessor blinded, randomised controlled trial. 378 participants with hip osteoarthritis requiring THR will be randomised (1:1) to receive robotic-assisted THR, or THR using conventional surgical instruments. The primary outcome is the Forgotten Joint Score at 12 months post-randomisation; a patient-reported outcome measure assessing participants' awareness of their joint when undertaking daily activities. Secondary outcomes will be collected post-operatively (pain, blood loss and opioid usage) and at 3, 6, 12, 24 months, then 5 and 10 years postrandomisation (including function, pain, health-related quality of life, reoperations and satisfaction). Allocation concealment will be accomplished using a computer-based randomisation procedure on the day of surgery. Blinding methods include the use of sham incisions for marker clusters and blinded operation notes. The primary analysis will adhere to the intention-to-treat principle. Results will adhere to Consolidated Standards of Reporting Trials statements. ETHICS AND DISSEMINATION: The trial was approved by an ethics committee (Solihull Research Ethics Committee, 30 June 2021, IRAS: 295831). Participants will provide informed consent before agreeing to participate. Results will be disseminated using peer-reviewed journal publications, presentations at international conferences and through the use of social media. We will develop plans to disseminate to patients and public with our patient partners. TRIAL REGISTRATION NUMBER: ISRCTN13374625.

Exploring key-stakeholder perceptions on non-communicable disease care during the COVID-19 pandemic in Kenya.

Introduction: over one third of total Disability-Adjusted-Life-Years lost in Kenya are due to non-communicable diseases (NCD). In response, the Government declared significant commitment towards improving NCD care. The COVID-19 pandemic increased the burden on the already overstretched health systems in Kenya. The aims of this study are to assess whether health care providers perceived NCD care to be optimal during the pandemic and explore how to improve responses to future emergencies. Methods: this cross-sectional online survey included healthcare personnel with non-clinical roles (public health workers and policy-makers) and those delivering health care (doctors and nurses). Respondents were recruited between May and September 2021 by random sampling, completed by snowball sampling. Results: among 236 participants (42% in clinical, 58% in non-clinical roles) there was an overall consensus between respondents on NCD care being disrupted and compromised during the pandemic in Kenya. Detracted supplies, funding, and technical resources affected the continuity of NCDs' response, despite government efforts. Respondents agreed that the enhanced personnel capacity and competencies to manage COVID-19 patients were positive, but noted a lack of guidance for redirecting care for chronic diseases, and advocated for digital innovation as a solution. Conclusion: this paper explores the perceptions of key stakeholders involved in the management of NCDs in Kenya to improve planning for future emergency responses. Gaps were identified in health system response and preparedness capacity during the pandemic including the perceived need to strengthen NCD services, with solutions offered to guide resilience efforts to protect the health system from disruption.

Neighbourhood risk factors of recurrent tuberculosis in Cape Town: a cohort study using geocoded notification data.

BACKGROUND: Individuals with a history of tuberculosis (TB) disease are at higher risk of developing a subsequent episode than those without. Considering the role of social and environmental factors in tuberculosis, we assessed neighbourhood-level risk factors associated with recurrent tuberculosis in Cape Town, South Africa. METHODS: This cohort consisted of patients who completed treatment for their first drug-sensitive TB episode between 2003 and 2015. Addresses were geocoded at neighbourhood level. Data on neighbourhood-level factors were obtained from the Census 2011 (household size, population density) and the City of Cape Town (Socio-Economic Index). Neighbourhood-level TB burden was calculated annually by dividing the number of notified TB episodes by the population in that neighbourhood. Multilevel survival analysis was performed with the outcome recurrent TB, defined as a second episode of TB, and controlling for individual-level risk factors (age, gender and time since first episode in years). Follow-up ended at the second episode, or on 31 December 2015, whichever came first. RESULTS: The study included 173 421 patients from 700 neighbourhoods. Higher Socio-Economic Index was associated with a lower risk of recurrence compared with average Socio-Economic Index. An increased risk was found for higher household size and TB burden, with an increase of 20% for every additional person in mean household size and 10% for every additional TB episode/100 inhabitants. No association was found with population density. CONCLUSION: Recurrent TB was associated with increased household size and TB burden at neighbourhood level. These findings could be used to target TB screening activities.

Houston, We Have a Problem: Reports of Clostridioides difficile Isolates With Reduced Vancomycin Susceptibility.

During the past 4 decades, oral vancomycin has been a mainstay of Clostridioides difficile infection (CDI) therapy with no reports of treatment failure due to emergence of vancomycin resistance. However, C. difficile isolates with high-level phenotypic resistance to vancomycin have recently been reported in 3 distinct geographic regions. There is an urgent need for surveillance to determine if strains with reduced vancomycin susceptibility are circulating in other areas. In a Cleveland-area hospital, screening of 176 CDI stool specimens yielded no C. difficile isolates with reduced vancomycin susceptibility and highlighted the potential for false-positive results due to contamination with vancomycin-resistant enterococci. Additional studies are needed to clarify whether reduced vancomycin susceptibility is an emerging problem that will alter clinical practice. Clinicians should alert their health department if they observe a substantial increase in the frequency of vancomycin treatment failure in patients diagnosed with CDI with no alternative explanation for diarrhea.

Bilateral sacroiliitis following group C streptococcal sepsis.

Reactive arthritis particularly affects individuals 20 to 40 years old. The most common preceding infections are enteric and urogenital. The association of group C and group G streptococcal infections with reactive arthritis is rare. We present a case of old-onset bilateral sacroiliitis following group C streptococcal infection in an 81-year-old woman, treated successfully with a steroid taper and infliximab.

Phase II Trial of Cabozantinib Plus Nivolumab in Patients With Non-Clear-Cell Renal Cell Carcinoma and Genomic Correlates.

PURPOSE: To assess the efficacy and safety of cabozantinib plus nivolumab in a phase II trial in patients with non-clear-cell renal cell carcinoma (RCC). PATIENTS AND METHODS: Patients had advanced non-clear-cell renal carcinoma who underwent 0-1 prior systemic therapies excluding prior immune checkpoint inhibitors. Patients received cabozantinib 40 mg once daily plus nivolumab 240 mg once every 2 weeks or 480 mg once every 4 weeks. Cohort 1 enrolled patients with papillary, unclassified, or translocation-associated RCC; cohort 2 enrolled patients with chromophobe RCC. The primary end point was objective response rate (ORR) by RECIST 1.1; secondary end points included progression-free survival, overall survival, and safety. Next-generation sequencing results were correlated with response. RESULTS: A total of 47 patients were treated with a median follow-up of 13.1 months. Objective response rate for cohort 1 (n = 40) was 47.5% (95% CI, 31.5 to 63.9), with median progression-free survival of 12.5 months (95% CI, 6.3 to 16.4) and median overall survival of 28 months (95% CI, 16.3 to not evaluable). In cohort 2 (n = 7), no responses were observed; one patient had stable disease > 1 year. Grade 3/4 treatment-related adverse events were observed in 32% treated patients. Cabozantinib and nivolumab were discontinued because of toxicity in 13% and 17% of patients, respectively. Common mutations included NF2 and FH in cohort 1 and TP53 and PTEN in cohort 2. Objective responses were seen in 10/12 patients with either NF2 or FH mutations. CONCLUSION: Cabozantinib plus nivolumab showed promising efficacy in most non-clear-cell RCC variants tested in this trial, particularly those with prominent papillary features, whereas treatment effects were limited in chromophobe RCC. Genomic findings in non-clear-cell RCC variants warrant further study as predictors of response.

Extreme γ' fibrinogen levels in COVID-19 patients

BackgroundCOVID-19 progression can be accompanied by a "cytokine storm" that leads to secondary sequelae such as thrombosis and acute respiratory distress syndrome. Several inflammatory cytokines have been associated with COVID-19 progression, but have far too much daily intra-individual variability to be useful in tracking the course of the disease. In contrast, we have shown that the inflammatory biomarker {gamma} fibrinogen ({gamma} Fbg) has a 6-fold lower coefficient of variability compared to other inflammatory markers such as hs-CRP. Objectives: The aims of the study were to measure {gamma} Fbg in serial blood samples from COVID-19 patients at a tertiary care medical center in order to investigate its association with clinical measures of disease progression. MethodsCOVID-19 patients at a tertiary care medical center were retrospectively enrolled between 3/16/2020 and 8/1/2020. {gamma} Fbg was measured using a commercial ELISA. Results: Our results showed that nine out of the seventeen patients with COVID-19 had extremely high levels of {gamma} Fbg. {gamma} Fbg levels were significantly associated with the need for ECMO and with mortality. ConclusionsWe found that COVID-19 patients can develop extraordinarily high levels of {gamma} Fbg. The previous highest {gamma} Fbg level that we are aware of was 80.3 mg/dL found in a study of 10,601 participants in the ARIC study. These results have several important clinical implications. {gamma} Fbg contains a high affinity binding site for thrombin that binds to anion-binding exosite II on thrombin and protects it from inactivation by heparin. High levels of {gamma} Fbg therefore provide a reservoir of heparin-resistant clot-bound thrombin when the {gamma} Fbg is clotted. These findings have potential implications regarding prophylactic anticoagulation of COVID-19 patients and suggest that heparin prophylaxis may be less effective than using other anticoagulants, particularly direct thrombin inhibitors.

Proteolytic activity and degradation of bovine versus human dentin matrices.

OBJECTIVE: Non-human teeth have been commonly used in research as replacements for human teeth, and potential dissimilarities between the dental tissues should be considered when interpreting the outcomes. To compare the proteolytic activity and degradation rate of bovine and human dentin matrices. METHODOLOGY: Dentin beam specimens were obtained from human molars (n=30) and bovine incisors (n=30). The beams were weighed hydrated and after complete dehydration to obtain the mineralized wet and dry masses. Then, the beams were demineralized in 10 wt% phosphoric acid. Next, 15 beams from each substrate were randomly selected and again dehydrated and weighed to obtain the initial demineralized dry mass (DM). Then, the beams were stored in saliva-like buffer solution (SLBS) for 7, 14 and 21 days. SLBS was used to evaluate hydroxyproline (HYP) release after each storage period. The remaining beams of each substrate (n=15) were tested for initial MMP activity using a colorimetric assay and then also stored in SLBS. DM and MMP activity were reassessed after 7, 14 and 21 days of incubation. The data were subjected to two-way ANOVA tests with repeated measures complemented by Bonferroni's tests. Unpaired two-tailed t-tests were also used (p<0.05). RESULTS: Similar water and inorganic fractions were found in human and bovine dentin, while human dentin had a higher protein content. The most intense proteolytic activity and matrix deterioration occurred short after dentin was demineralized. Both substrates exhibited a sharp reduction in MMP activity after seven days of incubation. Although human dentin had higher MMP activity levels, greater HYP release and DM loss after seven days than bovine dentin, after 14 and 21 days, the outcomes were not statistically different. CONCLUSION: Bovine dentin is a suitable substrate for long-term studies involving the degradation of dentin matrices.

Changes in dispensing of medicines proposed for re-purposing in the first year of the COVID-19 pandemic in Australia

ObjectiveWe quantified changes in dispensing of common medicines proposed for "re-purposing" due to their perceived benefits as therapeutic or preventive for COVID-19 in Australia, a country with relatively low COVID-19 incidence in the first year of the pandemic. MethodsWe performed an interrupted time series analysis and cross-sectional study using nationwide dispensing claims data (January 2017-November 2020). We focused on six subsidised medicines proposed for re-purposing: hydroxychloroquine, azithromycin, ivermectin, colchicine, corticosteroids, and calcitriol (Vitamin D analogue). We quantified changes in monthly dispensing and initiation trends during COVID-19 (March-November 2020) using autoregressive integrated moving average models (ARIMA) and compared characteristics of initiators in 2020 and 2019. ResultsIn March 2020, we observed a 99% (95%CI 96%-103%) increase in hydroxychloroquine dispensing (of which approximately 22% attributable to new use), and a 199% increase (95%CI 184%-213%) in initiation, with a shift towards prescribing by general practitioners (42% in 2020 vs 25% in 2019) rather than specialists. These increases subsided following regulatory restrictions on prescribing to relevant specialties. There was a small but sustained increase in ivermectin dispensing over multiple months, with a 80% (95%CI 42%-118%) increase in initiation in May 2020 following its first identification as potentially disease-modifying in April. Other than increases in March related to stockpiling, we observed no increases in initiation of calcitriol or colchicine during COVID-19. Dispensing of corticosteroids and azithromycin remained lower than expected in April through November 2020. ConclusionsWhile most increases in dispensing observed early on during COVID-19 were temporary and appear to be related to stockpiling among existing users, we did observed increases in initiation of hydroxychloroquine and ivermectin and a shift in prescribing patterns which may be related to media hype around these medicines. A quick response by regulators can help limit inappropriate repurposing to lessen the impact on medicine supply and patient harms.

Effect of tourniquet use on the risk of revision in total knee replacement surgery: an analysis of the National Joint Registry Data Set.

OBJECTIVE: Tourniquet use in total knee replacement (TKR) is believed to improve the bone-cement interface by reducing bleeding, potentially prolonging implant survival. This study aimed to compare the risk of revision for primary cemented TKR performed with or without a tourniquet. DESIGN: We analysed data from the National Joint Registry (NJR) for all primary cemented TKRs performed in England and Wales between April 2003 and December 2003. Kaplan-Meier plots and Cox regression were used to assess the influence of tourniquet use, age at time of surgery, sex and American Society of Anaesthesiologists (ASA) classification on risk of revision for all-causes. RESULTS: Data were available for 16 974 cases of primary cemented TKR, of which 16 132 had surgery with a tourniquet and 842 had surgery without a tourniquet. At 10 years, 3.8% had undergone revision (95% CI 2.6% to 5.5%) in the no-tourniquet group and 3.1% in the tourniquet group (95% CI 2.8% to 3.4%). After adjusting for age at primary surgery, gender and primary ASA score, the HR for all-cause revision for cemented TKR without a tourniquet was 0.82 (95% CI 0.57 to 1.18). CONCLUSIONS: We did not find evidence that using a tourniquet for primary cemented TKR offers a clinically important or statistically significant reduction in the risk of all-cause revision up to 13 years after surgery. Surgeons should consider this evidence when deciding whether to use a tourniquet for cemented TKR.

Moving Toward a New Standard of Care for Acute Pediatric Stroke.

Acute pediatric stroke is growing in incidence with the longer survivorship of children with medical complexities, yet detection and treatment of this disease continues to be met with limitations. It is essential for the frontline provider to appropriately identify various presentations of acute pediatric stroke for timely management to occur. Although studies in thrombolytic and endovascular recanalization therapies are limited, the safety and efficacy of these treatments continues to be explored. As pediatric tertiary care centers improve their stroke management, it is increasingly important to implement hospital protocols with a multifaceted approach. This article summarizes the issues and presentations behind identifying acute pediatric stroke, the research behind these emerging therapies in children, and the process of successfully applying pediatric stroke protocols. [Pediatr Ann. 2021;50(6):e242-e244.].

Asociación de fascioliasis con el estado nutricional y coinfección enteroparasitaria en niños / Association of fascioliasis to nutritional status and enteroparasite coinfection in children

Introducción: La fascioliasis es causada por el trematodo Fasciola hepatica que afecta a animales herbívoros, omnívoros y al humano. Los niños de edad escolar son los más afectados y el órgano más dañado es el hígado. Este parásito requiere de reservorio y huésped intermediario para completar su ciclo biológico. Objetivo: Determinar la asociación de la fascioliasis con el estado nutricional y coinfección enteroparasitaria en niños. Métodos: La investigación se realizó entre septiembre de 2016 y abril de 2017 en el distrito de Santa María de Chicmo, región Apurímac. El estudio fue analítico de corte transversal. La población de niños de 6 a 16 años estuvo constituida por 2 172 individuos. El tamaño de muestra fue de 435 niños y se determinó mediante un muestreo simple al azar. Además, para que el muestreo fuera más eficiente se distribuyó el tamaño total de la muestra entre los estratos I.E. Primaria e I.E. Secundaria, para un resultado de 209 y 226 muestras, respectivamente. Sin embargo, se logró tomar 493 muestras coprológicas y serológicas repartidas proporcionalmente entre la totalidad de 23 instituciones educativas. Resultados: La prevalencia de fascioliasis fue de 5,3 por ciento (26/493; IC95 por ciento =3,2-7,4). Las instituciones educativas con mayor prevalencia fueron: Taramba con 17,2 por ciento (5/29; IC95 por ciento = 5,9-35,8), Libertadores de América con 16,1 por ciento (5/31; IC95 por ciento = 5,5-33,7), Mariano Melgar con 15 por ciento (3/20; IC95 por ciento = 3,2-37,9) y Nuestra Señora de Guadalupe con 10,8 por ciento (4/37; IC95 por ciento = 3-25,4). No se encontró asociación de fascioliasis con la valoración nutricional antropométrica ni con la coinfección enteroparasitaria en niños (p˃ 0,05). Conclusiones: La fascioliasis no estaría afectando el estado nutricional de los niños; asimismo, los signos clínicos, atribuidos a fascioliasis, corresponderían también a la alta presentación de parásitos entéricos(AU)

Introduction: Fascioliasis is caused by the trematode Fasciola hepatica and affects herbivorous and omnivorous animals as well as humans. Schoolchildren are the most affected group, and the organ most commonly targeted is the liver. This parasite requires an intermediate reservoir and host to complete its biological cycle. Objective: Determine the association of fascioliasis to nutritional status and enteroparasite coinfection in children. Methods: An analytical cross-sectional study was conducted from September 2016 to April 2017 in the district of Santa María de Chicmo, Apurímac Region. The child population aged 6-16 years was composed of 2 172 individuals. The sample size was 435 children, and it was determined by simple random sampling. Additionally, in order for the sampling to be more efficient, the total sample size was distributed between the strata Primary E.I. and Secondary E.I., for 209 and 226 samples, respectively. However, 493 coprological and serological samples were proportionally taken from the total 23 educational institutions. Results: Prevalence of fascioliasis was 5.3 percent (26/493; CI95 percent=3.2-7.4). The educational institutions with the highest prevalence were Taramba with 17.2 percent (5/29; CI95 percent= 5.9-35.8), Libertadores de América with 16.1 percent (5/31; CI95 percent= 5.5-33.7), Mariano Melgar with 15 percent (3/20; CI95 percent= 3.2-37.9) and Nuestra Señora de Guadalupe with 10.8 percent (4/37; CI95 percent= 3-25.4). No association was found between fascioliasis and nutritional anthropometric assessment or enteroparasite coinfection in children (p˃ 0.05). Conclusions: Fascioliasis was not found to affect the nutritional status of children. On the other hand, the clinical signs attributed to fascioliasis also correspond to the high presentation of enteric parasites(AU)

Tourniquet use in total knee replacement surgery: a feasibility study and pilot randomised controlled trial (SAFE-TKR study).

INTRODUCTION: Tourniquets are routinely used during total knee replacement (TKR) surgery. They could increase the risk of thromboembolic events including cerebral emboli, cognitive decline, pain and other adverse events (AEs). A randomised controlled trial to assess whether tourniquet use might safely be avoided is therefore warranted but it is unclear whether such a trial would be feasible. METHODS: In a single-site feasibility study and pilot randomised controlled trial, adults having a TKR were randomised to surgery with an inflated tourniquet versus a non-inflated tourniquet. Participants underwent brain MRI preoperatively and within 2 days postoperatively. We assessed cognition using the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA) and Oxford Cognitive Screen (OCS) and thigh pain using a Visual Analogue Scale at baseline and days 1 and 2, and 1 week postsurgery. AEs related to surgery were recorded up to 12 months. RESULTS: We randomised 53 participants (27 tourniquet inflated and 26 tourniquet not inflated). Fifty-one participants received care per-protocol (96%) and 48 (91%) were followed up at 12 months. One new ischaemic brain lesion was detected. Of the cognitive tests, MoCA was easy to summarise, sensitive to change with lower ceiling effects compared with OCS and MMSE. There was a trend towards more thigh pain (mean 49.6 SD 30.4 vs 36.2 SD 28 at day 1) and more AEs related to surgery (21 vs 9) in participants with an inflated tourniquet compared with those with a tourniquet not inflated. CONCLUSION: A full trial is feasible, but using MRI as a primary outcome is unlikely to be appropriate or feasible. Suitable primary outcomes would be cognition measured using MoCA, pain and AEs, all of which warrant investigation in a large multicentre trial. TRIAL REGISTRATION NUMBER: ISRCTN20873088.

Proteolytic activity and degradation of bovine versus human dentin matrices

Abstract Non-human teeth have been commonly used in research as replacements for human teeth, and potential dissimilarities between the dental tissues should be considered when interpreting the outcomes. Objective: To compare the proteolytic activity and degradation rate of bovine and human dentin matrices. Methodology: Dentin beam specimens were obtained from human molars (n=30) and bovine incisors (n=30). The beams were weighed hydrated and after complete dehydration to obtain the mineralized wet and dry masses. Then, the beams were demineralized in 10 wt% phosphoric acid. Next, 15 beams from each substrate were randomly selected and again dehydrated and weighed to obtain the initial demineralized dry mass (DM). Then, the beams were stored in saliva-like buffer solution (SLBS) for 7, 14 and 21 days. SLBS was used to evaluate hydroxyproline (HYP) release after each storage period. The remaining beams of each substrate (n=15) were tested for initial MMP activity using a colorimetric assay and then also stored in SLBS. DM and MMP activity were reassessed after 7, 14 and 21 days of incubation. The data were subjected to two-way ANOVA tests with repeated measures complemented by Bonferroni's tests. Unpaired two-tailed t-tests were also used (p<0.05). Results: Similar water and inorganic fractions were found in human and bovine dentin, while human dentin had a higher protein content. The most intense proteolytic activity and matrix deterioration occurred short after dentin was demineralized. Both substrates exhibited a sharp reduction in MMP activity after seven days of incubation. Although human dentin had higher MMP activity levels, greater HYP release and DM loss after seven days than bovine dentin, after 14 and 21 days, the outcomes were not statistically different. Conclusion: Bovine dentin is a suitable substrate for long-term studies involving the degradation of dentin matrices.

Repeat testing for SARS-COV-2: Persistence of viral RNA is common, and clearance is slower in older age groups

OBJECTIVEQueenslands Novel Coronavirus (SARS-CoV-2) suppression program has been relatively successful. Initially, it involved extensive community testing and repeat sampling of positive individuals for release from isolation. This enabled study of several characteristics, including persistence of detectable virus and how apparent viral clearance rates varied by age and sex. DESIGNWe conducted an exploratory analysis of Queensland Pathology SARS-CoV-2 reverse transcriptase polymerase chain reaction (RT-PCR) test results. Kaplan Meier analyses were used to estimate median time to apparent viral clearance, and Cox regression to explore the effects of sex and age. SETTING AND PARTICIPANTSIndividuals tested for presence of SARS-CoV-2 in the upper respiratory tract between January 19 and June 4, 2020. OUTCOME MEASURESPresence of viral RNA detected by RT-PCR. RESULTSWe analyzed 97,476 individuals. Median age was 41y (range <1-105y), and 57.2% (95% CI 57.2, 57.2) were female. In total, 958 (0.98%; 95% CI 0.92,1.05) tested positive for SARS-CoV-2. Positivity rates were lower in regional areas than cities, in females (OR 0.80, 95% CI 0.70, 0.91), and in those aged 16y and below (p<0.01, test for trend). Of the 958 positive individuals, 243 had two or more (max 17) additional tests, and 92% (95% CI 88.1, 95.2) remained positive after 10 days (max 76 days) after the initial result. Median time to apparent viral clearance was longer in those 65y and over compared to those under 65y (29 v 43 days, HR 1.85; 95% CI 1.17, 2.90), and was unaffected by sex (HR 0.93; 95% CI 0.66, 1.30). CONCLUSIONSFemales and those 16y and under were less likely to test positive for SARS-CoV-2. Detectable RNA may persist for long periods, negating the value of repeat testing for declaring individuals free of infection. Viral clearance rates appear lower in those over 65y of age compared with younger individuals. "The known" - Early in the COVID-19 pandemic, 2 negative RT-PCR swabs were used to achieve negative status in infected individuals - There are few published data on the patterns of results seen with repeat testing in Australia. "The new" - We analysed data from a large cohort of people tested for viral RNA in Queensland - We found that females and those 16 y and under were less likely to test positive. - Viral RNA was detectable for up to 76 days, with >90% testing positive for more than 10 days. - Viral clearance was slower in those over the age of 65. "The implications" - There is likely to be little value in repeat RT-PCR testing to declare individuals free from infection. The first Australian cases of infection with SARS-CoV-2 were reported in January 2020.1 During the initial phase the peak daily infection rate was in late March 2020 and by the end of June 2020 there had been around 8000 cases and 104 deaths.2 Initially, the majority of cases were acquired outside the country rather than by local transmission.3 The cumulative incidence rates (June 2020) of around 400/million, and mortality of 4/million, were towards the lower end of the rates that have been experienced in other high-income countries, although these are rising quickly with recent outbreaks in Victoria and New South Wales.3 Rates of infection remain relatively low in Queensland.3 In Queensland, the criteria for testing individuals for SARS-CoV-2 changed during the pandemic. Initially, to be tested in Queensland people were required to meet both epidemiological (return from a high-risk country), and clinical criteria (suggestive symptoms). With progression of the pandemic, testing criteria were modified to clinical criteria only (details provided below). The rollout of a comprehensive testing program and the availability of data from repeated within-subject testing carried out in the initial stages of the Covid-19 pandemic provided an opportunity to conduct an exploratory study to address several questions. We investigated population testing rates and how they varied over time. We estimated the proportions of individuals who returned positive tests and how these varied with location age and sex. We also estimated apparent rates of clearance of viral RNA from the upper respiratory tract of subjects with repeated tests, and the extent to these varied with age and sex.

Monolayer Semiconductor Auger Detector.

Auger recombination in semiconductors is a many-body phenomenon in which the recombination of electrons and holes is accompanied by excitation of other charge carriers. The excess energy of the excited carriers is normally rapidly converted to heat, making Auger processes difficult to probe directly. Here, we employ a technique in which the Auger-excited carriers are detected by their ability to tunnel out of the semiconductor through a thin barrier, generating a current. We use vertical van der Waals heterostructures with monolayer WSe2 as the semiconductor, with hexagonal boron nitride as the tunnel barrier, and a graphite collector electrode. The Auger processes combined with resonant absorption produce characteristic negative photoconductance. We detect holes Auger-excited by both neutral and charged excitons and find that the Auger scattering is surprisingly strong under weak excitation. Our work expands the range of techniques available for probing relaxation processes in 2D materials.