How distant? An experimental analysis of students' COVID-19 exposure and physical distancing in university buildings.

Closed university buildings proved to be one of the main hot spots for virus transmission during pandemics. As shown during the COVID-19 pandemic, physical distancing is one of the most effective measures to limit such transmission. As universities prepare to manage in-class activities, students' adherence to physical distancing requirements is a priority topic. Unfortunately, while physical distancing in classrooms can be easily managed, the movement of students inside common spaces can pose high risk of close proximity. This paper provides an experimental analysis of unidirectional student movement inside a case-study university building to investigate how physical distancing requirements impact student movement and grouping behaviour. Results show general adherence with the minimum required physical distancing guidance, but spaces such as corridors pose higher risk of exposure than doorways. Doorway width, in combination with group behaviour, affect the students' capacity to keep the recommended physical distance. Furthermore, questionnaire results show that students report higher perceived vulnerability while moving along corridors. Evidence-based results can support decision-makers in understanding individuals' exposure to COVID-19 in universities and researchers in developing behavioural models in preparation of future outbreaks and pandemics.

A large multicenter cohort on the use of full-thickness resection device for difficult colonic lesions.

BACKGROUND: Introduction of the full-thickness resection device (FTRD) has allowed endoscopic resection of difficult lesions such as those with deep wall origin/infiltration or those located in difficult anatomic locations. The aim of this study is to assess the outcomes of the FTRD among its early users in the USA. METHODS: Patients who underwent endoscopic full-thickness resection (EFTR) for lower gastrointestinal tract lesions using the FTRD at 26 US tertiary care centers between 10/2017 and 12/2018 were included. Primary outcome was R0 resection rate. Secondary outcomes included rate of technical success (en bloc resection), achievement of histologic full-thickness resection (FTR), and adverse events (AE). RESULTS: A total of 95 patients (mean age 65.5 ± 12.6 year, 38.9% F) were included. The most common indication, for use of FTRD, was resection of difficult adenomas (non-lifting, recurrent, residual, or involving appendiceal orifice/diverticular opening) (66.3%), followed by adenocarcinomas (22.1%), and subepithelial tumors (SET) (11.6%). Lesions were located in the proximal colon (61.1%), distal colon (18.9%), or rectum (20%). Mean lesion diameter was 15.5 ± 6.4 mm and 61.1% had a prior resection attempt. The mean total procedure time was 59.7 ± 31.8 min. R0 resection was achieved in 82.7% while technical success was achieved in 84.2%. Histologically FTR was demonstrated in 88.1% of patients. There were five clinical AE (5.3%) with 2 (2.1%) requiring surgical intervention. CONCLUSIONS: Results from this first US multicenter study suggest that EFTR with the FTRD is a technically feasible, safe, and effective technique for resecting difficult colonic lesions.

Formation and loss of metastable brucite: does Fe(II)-bearing brucite support microbial activity in serpentinizing ecosystems?

Ultramafic rocks undergo successive stages of hydration and oxidation during water/rock interaction, giving rise to secondary minerals such as brucite, serpentine, magnetite and the production of H2(g). Ferroan brucite (MgxFe(1-x)2+(OH)2) often forms under low water/rock ratios early during the 'serpentinization' process. The formation of ferroan brucite sequesters Fe(II) and suppresses the production of H2, thereby limiting the flux of reductants suitable for sustaining microbial metabolism. Yet ferroan brucite is a relatively soluble mineral 'reservoir' for reactive Fe(II). Brucite is often metastable and can be lost at later stages of peridotite hydration when there is a significant increase in the water/rock ratio or the activity of SiO2 or CO2. The Fe(OH)2 component of brucite has the thermodynamic potential to reduce most aqueous oxidants. Therefore, ferroan brucite may reduce water and/or dissolved carbon, nitrogen and sulfur species, while the Fe(II) is converted into more stable secondary minerals such as Fe(II/III)-oxides and hydroxides (e.g. green-rust, magnetite, iowaite and pyroaurite) and ferric serpentine. The reactivity of ferroan brucite, and the associated rate of Fe solubilization and oxidation in subsurface fluids, could be a key regulator on the rate of electron transfer from serpentinites to the rock-hosted biosphere. Aqueous alteration of ferroan brucite may significantly modulate the H2 activity in fluids circulating within partially serpentinized rocks, and buffer H2 as it is lost by advection or in situ consumption by a hydrogenotrophic microbial community. Moreover, there may be microbial organisms that specifically colonize and use ferroan brucite as an electron donor for their metabolism. The energy fluxes sustained by localized brucite oxidation may often be sufficiently large to sustain abundant microbial communities; water/rock reaction zones where brucite is consumed could serve as environments to search for extant or fossil serpentinite-hosted life. This article is part of a discussion meeting issue 'Serpentinite in the Earth System'.

Development and validation of a prognostic model for overall survival in chemotherapy-naïve men with metastatic castration-resistant prostate cancer.

Background: Prognostic models are needed that reflect contemporary practice for men with metastatic castration-resistant prostate cancer (mCRPC). We sought to identify predictive and prognostic variables for overall survival (OS) in chemotherapy-naïve men with mCRPC treated with enzalutamide. Patients and methods: Patients from the PREVAIL trial database (enzalutamide versus placebo) were randomly split 2 : 1 into training (n = 1159) and testing (n = 550) sets. Using the training set, 23 predefined variables were analyzed and a multivariable model predicting OS was developed and validated in an independent testing set. Results: Patient characteristics and outcomes were well balanced between training and testing sets; median OS was 32.7 months in each. The final validated multivariable model included 11 independent prognostic variables. Median OS for low-, intermediate-, and high-risk groups (testing set) defined by prognostic risk tertiles were not yet reached (NYR) (95% CI NYR-NYR), 34.2 months (31.5-NYR), and 21.1 months (17.5-25.0), respectively. Hazard ratios (95% CI) for OS in the low- and intermediate-risk groups versus high-risk group were 0.20 (0.14-0.29) and 0.40 (0.30-0.53), respectively. Secondary outcomes of response and progression differed widely in model-defined risk groups. Enzalutamide improved outcomes in all prognostic risk groups. Conclusions: Our validated prognostic model incorporates variables routinely collected in chemotherapy-naïve men with mCRPC treated with enzalutamide, identifying subsets of patients with widely differing survival outcomes that provide useful information for external validation, patient care, and clinical trial design. Trial registration: ClinicalTrials.gov: NCT01212991.

Prognostic role for the derived neutrophil-to-lymphocyte ratio in early breast cancer: a GEICAM/9906 substudy.

PURPOSE: Elevated markers of host inflammation, a hallmark of cancer, have been associated with worse outcomes in several solid tumors. Here, we explore the prognostic role of the derived neutrophil-to-lymphocyte ratio (dNLR), across different tumor subtypes, in patients with early breast cancer. PATIENTS AND METHODS: This was a retrospective analysis of 1246 patients with lymph node-positive, operable early breast cancer enrolled in the GEICAM/9906 trial, a multicenter randomized phase 3 study evaluating adjuvant chemotherapy. dNLR was calculated as the ratio of neutrophils and the difference between total leukocytes and neutrophils in peripheral blood before chemotherapy. Disease-free survival (DFS) and overall survival were explored using a Cox proportional hazard analysis. RESULTS: The analysis comprised 1243 (99.8%) patients with dNLR data, with a median follow-up of 10 years. Data on intrinsic subtypes were available from 818 (66%) patients (luminal A 34%, luminal B 32%, HER2-enriched 21% and basal-like 9%). Median dNLR was 1.35 [interquartile range (IQR) 1.08-1.71]. In the whole population, dNLR was not prognostic after adjustment for clinico-pathological factors. However, dNLR ≥ 1.35 was independently associated with worse DFS in the hormone receptor-negative/HER2+ population (HR 2.86; p = 0.038) and in patients with one to three lymph node metastases (HR 1.32, p = 0.032). There was a non-significant association with worse DFS in non-luminal and in HER2-enriched tumors (HR 1.40, p = 0.085 and HR 1.53, p = 0.067). No significant interaction was observed between the treatment arm and dNLR. CONCLUSION: Elevated dNLR appears to be an adverse prognostic factor in hormone receptor-negative early breast cancer. TRIAL REGISTRATION: EudraCT: 2005-003108-12 (retrospectively registered 28/06/2005). ClinicalTrials.gov Identifier: NCT00129922 (retrospectively registered 10/08/2005). Results of this study were presented in part at the 2016 ESMO conference October 7-11, 2016, Copenhagen, Denmark (oral presentation).

Hyperglycaemia and Survival in Solid Tumours: A Systematic Review and Meta-analysis.

AIMS: Diabetes is associated with adverse cancer outcomes. However, the effect of hyperglycaemia in non-diabetic cancer patients is unclear. MATERIALS AND METHODS: A systematic search of electronic databases identified publications exploring the effect of hyperglycaemia on overall survival, disease-free survival (DFS) or progression-free survival (PFS). Data from studies reporting a hazard ratio and 95% confidence interval and/or a P-value were pooled in a meta-analysis using generic inverse-variance and random effects modelling. Subgroup analyses were conducted based on method of hyperglycaemia measurement (HbA1c, other) and stage (early, advanced, mixed). Meta-regression was performed to evaluate the influence of clinical characteristics including baseline diabetes status on the hazard ratio for overall survival. RESULTS: Twelve studies comprising a total of 9872 patients were included. All studies reported hazard ratios for overall survival. Three studies reported DFS; two reported PFS outcomes. Definitions of hyperglycaemia and cut-offs varied between studies. Hyperglycaemia was associated with worse overall survival (hazard ratio 2.05, 95% confidence interval 1.67-2.51; P < 0.001) and DFS (hazard ratio 1.98, 95% confidence interval 1.20-3.27; P = 0.007), but did not affect PFS (hazard ratio 1.08, 95% confidence interval 0.72-1.62; P = 0.71). The association with worse overall survival was maintained in subgroups based on method of hyperglycaemia measurement (subgroup difference P = 0.46) and stage (P = 0.14). Meta-regression showed a significantly greater magnitude of association between hyperglycaemia and decreased overall survival in studies with higher proportions of women and diabetic patients. CONCLUSIONS: Hyperglycaemia is associated with adverse overall survival and DFS in patients with cancer. The therapeutic role of glycaemic control in cancer patients warrants further investigation.

Parallel habitat acclimatization is realized by the expression of different genes in two closely related salamander species (genus Salamandra).

The utilization of similar habitats by different species provides an ideal opportunity to identify genes underlying adaptation and acclimatization. Here, we analysed the gene expression of two closely related salamander species: Salamandra salamandra in Central Europe and Salamandra infraimmaculata in the Near East. These species inhabit similar habitat types: 'temporary ponds' and 'permanent streams' during larval development. We developed two species-specific gene expression microarrays, each targeting over 12 000 transcripts, including an overlapping subset of 8331 orthologues. Gene expression was examined for systematic differences between temporary ponds and permanent streams in larvae from both salamander species to establish gene sets and functions associated with these two habitat types. Only 20 orthologues were associated with a habitat in both species, but these orthologues did not show parallel expression patterns across species more than expected by chance. Functional annotation of a set of 106 genes with the highest effect size for a habitat suggested four putative gene function categories associated with a habitat in both species: cell proliferation, neural development, oxygen responses and muscle capacity. Among these high effect size genes was a single orthologue (14-3-3 protein zeta/YWHAZ) that was downregulated in temporary ponds in both species. The emergence of four gene function categories combined with a lack of parallel expression of orthologues (except 14-3-3 protein zeta) suggests that parallel habitat adaptation or acclimatization by larvae from S. salamandra and S. infraimmaculata to temporary ponds and permanent streams is mainly realized by different genes with a converging functionality.

Impact of single-agent daily prednisone on outcomes in men with metastatic castration-resistant prostate cancer.

BACKGROUND: Despite palliative benefits and PSA responses, the objective clinical impact of daily oral prednisone (P) for metastatic castration-resistant prostate cancer (mCRPC) is unknown. We performed a pooled analysis of control arms of randomized trials that either did or did not administer single-agent P to evaluate its impact on overall survival (OS) and toxicities. METHODS: Individual patient data from control arms of randomized trials of men with mCRPC who received placebo or P+placebo post docetaxel were eligible for analysis. The impact of P on OS and severe toxicities was investigated in Cox regression models adjusted for known prognostic factors. Statistical significance was defined as P<0.05 and all tests were two sided. RESULTS: Data from the control arms of two randomized phase III trials were available totaling 794 men: the COU-AA-301 trial (n=394) administered P plus placebo and the CA184-043 trial (n=400) administered placebo alone. P plus placebo was not significantly associated with OS compared with placebo in a multivariable analysis (hazard ratio=0.89 (95% confidence interval 0.72-1.10), P=0.27). Other factors associated with poor OS were Eastern Cooperative Oncology Group (ECOG)-performance status (PS) ⩾1, Gleason score ⩾8, liver metastasis, high PSA, hypoalbuminemia and elevated lactate dehydrogenase (LDH). Grade ⩾3 therapy-related toxicities were significantly increased with P plus placebo compared with placebo (hazard ratio=1.48 (95% confidence interval 1.03-2.13), P=0.034). Other baseline factors significantly associated with a higher risk of grade ⩾3 toxicities were ECOG-PS ⩾1, hypoalbuminemia and elevated LDH. Fatigue, asthenia, anorexia and pain were not different based on P administration. CONCLUSIONS: P plus placebo was associated with higher grade ⩾3 toxicities but not extension of OS compared with placebo alone in men with mCRPC who received prior docetaxel. Except for the use of P with abiraterone to alleviate toxicities, the use of P should be questioned given its association with toxicities and resistance.

Evolution in the eligibility criteria of randomized controlled trials for systemic cancer therapies.

BACKGROUND: Eligibility criteria in randomized controlled trials (RCTs) reduce inter-patient heterogeneity, but may reduce generalizability of results. Here, we explore temporal changes in eligibility criteria of practice-changing RCTs for systemic cancer therapies and in the proportion of patients excluded from these trials after application of eligibility criteria. METHODS: An electronic search identified practice-changing RCTs published in six major journals between July 2010 and December 2012. Trial protocols were identified through journal websites and communication with authors or study sponsors. Eligibility criteria were extracted from protocols. The number of patients excluded after application of eligibility criteria was extracted from the CONSORT diagrams and text of publications. Changes in eligibility criteria over time were assessed by logistic regression and meta-regression was carried out to evaluate the impact of year of protocol on the proportion of patients who were excluded after screening. RESULTS: Eighty-six protocols written between 1987 and 2012 were included. Over time, there has been an increasing frequency of exclusion of patients with prior cerebrovascular events (OR 1.34, p=0.003), coagulation/bleeding disorders (OR 1.34, p=0.006), prior gastrointestinal bleeding (OR 1.33, p=0.01), cardiac co-morbidities (OR 1.24, p=0.004) and exclusion based on concurrent medication (OR 1.19, p=0.01). There has been a decrease in upper age limit usage (OR 0.83, p=0.01) and leukopenia (OR 0.83, p=0.009). The proportion of patients excluded from trials has increased from 9% prior to 2000 to 18% after 2010 (p-value for trend <0.001). CONCLUSIONS: RCTs have become less representative of cancer patients treated in routine practice with increased use of organ-specific and co-morbidity-based exclusion criteria.

Impact of Geographic Region on Benefit of Approved Anticancer Drugs Evaluated in International Phase III Clinical Trials.

AIMS: International collaboration allows for enhanced accrual and more generalisable results of phase III randomised controlled trials (RCTs). The impact of geographic region on the outcomes of new anticancer agents is unclear. MATERIALS AND METHODS: International RCTs evaluating approved systemic therapy for advanced solid tumours that reported efficacy of new anticancer drugs based on geographic regions were eligible. Data for overall (OS) or progression-free survival (PFS) were pooled in a meta-analysis. The primary analysis was the comparison of developed versus developing countries. A meta-regression analysis explored the impact of differences in gross national income (GNI) per capita on the hazard ratio comparing developed and developing countries. Secondary analyses compared geographic regions irrespective of GNI. RESULTS: Of the 63 identified studies, 12 independent RCTs were eligible; five reported data for OS and nine for PFS. Improvements in overall survival were greater in developed as compared with developing countries (hazard ratio 0.82, 95% confidence interval 0.68-0.99, P = 0.04). This effect was seen only among studies of cytotoxic chemotherapy and not among those of targeted agents. No difference was seen for PFS (hazard ratio 0.93, 95% confidence interval 0.79-1.09, P = 0.36). Meta-regression showed a significant negative association between GNI per capita and overall survival, but a non-significant negative association with PFS (ß = -0.774, P = 0.05 and ß = -0.211, P = 0.29, respectively). No differences were observed in PFS between Asian and non-Asian countries or North America and Western Europe. CONCLUSION: Compared with patients from developing countries, those from developed countries derive greater improvement in overall survival from cytotoxic chemotherapy, but similar benefit from targeted drugs.

Baseline neutrophil-lymphocyte ratio (NLR) is associated with survival and response to treatment with second-line chemotherapy for advanced prostate cancer independent of baseline steroid use.

BACKGROUND: The neutrophil-lymphocyte ratio (NLR), proposed as an indicator of cancer-related inflammation, has known prognostic value in prostate cancer. We examine its association with survival (OS) and response in patients treated with second-line chemotherapy. METHODS: We analysed patients with metastatic castration-resistant prostate cancer (mCRPC) treated in the TROPIC trial, evaluating cabazitaxel versus mitoxantrone. Cox regression models were used to investigate the association of baseline NLR (BLNLR) with OS and the significance of a change in NLR count with treatment. Logistic regression models were used to determine the association of BLNLR counts with prostate specific antigen (PSA) and RECIST responses. The optimal NLR cut-off was established based on the concordance index of different values. RESULTS: Data from 755, 654 and 405 patients was available for OS, PSA and RECIST response analysis respectively. Median OS was 14.0 months [95% confidence interval (CI) 13.2-14.8]. Median NLR was 2.9 (IQR: 1.9-5.1). BLNLR was associated with survival (HR 1.5, 95% CI 1.1-2.1, P = 0.011) in multivariable analysis (MVA) independently of variables included in the Halabi nomogram, treatment arm and corticosteroid use. The optimal cut-off for a dichotomous NLR was selected at 3.0 based on its higher c-index related to survival. BLNLR ≥3.0 was associated with lower PSA response (40.1% versus 59.9%; P < 0.001) and RECIST response (7.7% versus 15.6%, P = 0.022) in MVA. Conversion from high (≥3) to low (<3) NLR was associated with improved survival (HR 0.66; 95% CI 0.51-0.85; P = 0.001) and higher PSA response rates (66.4% versus 33.6%; P = 0.000). Use of corticosteroids at baseline did not modify the association between NLR and survival. CONCLUSIONS: NLR is a valid prognostic biomarker in CRPC and is associated with survival, PSA and RECIST responses in patients treated with second-line chemotherapy. Changes in NLR counts with treatment may indicate benefit. NLR prognostic value is independent of prior use of corticosteroids. CLINICALTRIALSGOV: NCT00417079.

Neutrophil-to-lymphocyte ratio as a prognostic biomarker for men with metastatic castration-resistant prostate cancer receiving first-line chemotherapy: data from two randomized phase III trials.

BACKGROUND: The neutrophil-to-lymphocyte ratio (NLR), a marker of host inflammation, has been associated with poor outcome in several solid tumors. Here, we investigated associations of the derived NLR (dNLR) and duration of initial androgen deprivation therapy (ADT) with survival of men with metastatic castration-resistant prostate cancer (mCRPC) receiving first-line chemotherapy. PATIENTS AND METHODS: Data from the multinational randomized phase III studies VENICE and TAX327 included a total of 2230 men with mCRPC randomized to receive first-line chemotherapy, and were used as training and validation sets, respectively. Associations of dNLR and duration of initial ADT with overall survival (OS) were evaluated by multivariable Cox regression analysis in the training set stratified for performance status and treatment arm. The model was then tested in the validation set. Subsequently, we investigated the treatment effect of docetaxel on OS in subgroups according to dNLR and duration of initial ADT. RESULTS: In the training set, both dNLR ≥median (2) and duration of initial ADT

Managing patients on bisphosphonates: the practice of primary care dentists before and after the publication of national guidance.

BACKGROUND: In April 2011 the Scottish Dental Clinical Effectiveness Programme published the Oral health management of patients prescribed bisphosphonates guidance document. The aims of this study were to examine whether dentists' practice and beliefs changed after guidance publication to determine whether a knowledge translation intervention was required, and to inform its development. METHODS: Three postal surveys sent to three independent, random samples of dentists throughout Scotland pre- and post-guidance publication. The questionnaire, framed using the theoretical domains framework (TDF), assessed current practice and beliefs relating to recommended management of patients on bisphosphonates. RESULTS: The results (N = 420) suggest that any significant impact the guidance may have had on the recommended management of patients on bisphosphonates by primary care dentists, had reached its peak ten months post publication. A more positive attitude, greater perceived ability, and greater motivation were all associated with significantly more performing of all recommended behaviours at every time point. CONCLUSIONS: Prior to this study, there was little available information about how patients on bisphosphonates were being managed in primary dental care, or what beliefs may be influencing management decisions. This study was able to identify levels of compliance pre- and post-guidance publication and determine that further intervention was necessary to enable sustained uptake of recommendations. Using the TDF to identify beliefs associated with best practice made it possible to suggest theoretically informed strategies for service improvement. The next step is to test the intervention(s) in a randomised controlled trial.

Reporting of occupational exposures to blood and body fluids in the primary dental care setting in Scotland: an evaluation of current practice and attitudes.

OBJECTIVES: To evaluate experience, practice and beliefs regarding occupational exposures to blood and oral fluids among a random sample of 300 dentists working in Scotland's NHS primary dental services. METHOD: A cross-sectional postal survey assessed occupational exposure policies and procedures, recent occupational exposure incidence and current management. Beliefs were measured using constructs from the theory of planned behaviour, shown to influence behaviour in this population. RESULTS: Forty-two percent of dentists responded. Fourteen percent had sustained an occupational exposure in the previous 12 months; of those, 35% did not report their exposure. All respondents' practices had protocols in place for managing and reporting dental team member sharps injuries. Most (82%) had protocols for mucocutaneous exposures. Less than half (48%) had a protocol for managing and reporting patient exposures to blood or saliva. Dentists placed significantly more importance (z-score -4.44, p value <0.001) and necessity (z-score -4.17, p value <0.001) on reporting patient exposure than dentist occupational exposure. CONCLUSION: This study suggests that while dentists generally have positive beliefs about reporting occupational exposures, there are gaps in practice.