Reporting of paediatric osteoporotic vertebral fractures in Duchenne muscular dystrophy and potential impact on clinical management: the need for standardised and structured reporting.

BACKGROUND: In boys with Duchenne muscular dystrophy (DMD), initiation of bisphosphonate is recommended upon identification of moderate or severe vertebral fractures, even if asymptomatic. Clear radiological reporting is important for consistency of clinical interpretation and management. OBJECTIVES: To audit radiology reports of spine imaging for vertebral fracture assessment in DMD, and assess potential impact on diagnosis and management. MATERIALS AND METHODS: Lateral thoracolumbar spine imaging (71 lateral spine radiographs and 13 lateral dual energy absorptiometry spine image) in 84 boys with DMD performed across two centres. Anonymised radiology reports by paediatric radiologists were circulated to two neuromuscular clinicians and two endocrinologists. Clinicians determined if there was vertebral fracture, no vertebral fracture, or unclear interpretation. Endocrinologists also determined if bisphosphonate was indicated. A single observer (a clinician with expertise in vertebral fracture assessment) performed vertebral fracture assessment in 37 images and re-reported using a structured format. Structured reports were re-circulated to the four clinicians to re-evaluate the degree of concordance in clinical diagnosis of vertebral fracture and treatment decisions with bisphosphonate. RESULTS: The term "fracture" was used in 25/84 (30%) radiology reports and only in 8/43 (19%) with description of vertebral body abnormalities. Fracture grading was included in 7/43 (16%) radiology reports. Diagnostic concordance by the clinicians was noted in 36/84 (43%). Unclear interpretation was noted in 22% to 51% based on radiology reports. No unclear interpretation was noted with structured reports. Complete diagnostic (37/37, 100%) and treatment (37/37, 100%) concordance was noted with the structured reports, whereas complete diagnostic and treatment concordance was noted in only 16/37 (43%) and 17/37 (46%) of the radiology reports, respectively. CONCLUSION: Only a third of radiology reports of spine imaging in DMD explicitly used the terminology "fracture". Grading was only noted in a small percentage. Variability in diagnostic interpretation by clinicians may lead to differing management plans. As identification of vertebral fracture is a trigger for treatment, developing reporting guidelines for paediatric vertebral fracture assessment will improve care. A structured template should be introduced for radiological reporting of paediatric vertebral fracture assessment.

Findings from the first public COVID-19 temporary test centre in Hong Kong.

INTRODUCTION: The Hospital Authority of Hong Kong Special Administrative Region established a coronavirus disease 2019 (COVID-19) temporary test centre at the AsiaWorld-Expo from March 2020 to April 2020, which allowed high-risk individuals to undergo early assessment of potential severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This study reviewed the characteristics and outcomes of individuals who attended the centre for COVID-19 testing. METHODS: This retrospective cross-sectional study collected epidemiological and clinical data. The primary outcome was a positive or negative SARS-CoV-2 test result, according to reverse transcription polymerase chain reaction analyses of pooled nasopharyngeal and throat swabs collected at the centre. The relationships of clinical characteristics with SARS-CoV-2 positive test results were assessed by multivariable binary logistic regression. RESULTS: Of 1258 attendees included in the analysis, 86 individuals tested positive for SARS-CoV-2 infection (positivity rate=6.84%; 95% confidence interval [CI]=5.57%-8.37%). Of these 86 individuals, 40 (46.5%) were aged 15 to 24 years and 81 (94.2%) had a history of recent travel. Symptoms were reported by 86.0% and 96.3% of individuals with positive and negative test results, respectively. The clinical characteristics most strongly associated with a positive test result were anosmia (adjusted odds ratio [ORadj]=8.30; 95% CI=1.12-127.09) and fever ORadj=1.32; 95% CI=1.02-3.28). CONCLUSION: The temporary test centre successfully helped identify individuals with COVID-19 who exhibited mild disease symptoms. Healthcare providers should carefully consider the epidemiological and clinical characteristics of COVID-19 to arrange early testing to reduce community spread.

Systematic review of the effects of bisphosphonates on bone density and fracture incidence in childhood acute lymphoblastic leukaemia.

Skeletal fragility is a common complication of childhood acute lymphoblastic leukaemia (ALL) but the impact of bisphosphonate therapy on bone mass and fracture is unclear. We aim to conduct a systematic review to evaluate the effects of bisphosphonates on bone mineral density (BMD) and fracture incidence in children with ALL. METHODS: EMBASE, Medline and the Cochrane Library were thoroughly searched by two researchers. Inclusion criteria was any child under the age of 18 years with a diagnosis of ALL, who had received any bisphosphonate treatment and had serial measurements of bone density performed thereafter. All primary research studies of any study design, excluding case reports, were included. RESULTS: Ten full text papers were identified with two exclusively meeting the inclusion criteria. Both studies administered bisphosphonates to children receiving maintenance chemotherapy for varying durations. Bone density was assessed at regular intervals by dual x-ray absorptiometry (DXA). The majority of participants had an improvement in bone density at the end of each study. However, no size adjustment of DXA data was performed. Limited information on fracture occurrence was provided by one study but did not include routine screening for vertebral fractures. CONCLUSIONS: This systematic review identified that there is insufficient evidence to support routine use of prophylactic bisphosphonate therapy in childhood ALL for prevention of fracture and improvement of bone mass. Future well-designed clinical trials in those at highest risk of fractures in ALL are now needed.

Feasibility of Dual Energy X-Ray Absorptiometry Based Images for Measurement of Height, Sitting Height, and Leg Length in Children.

BACKGROUND: Interpretation of pediatric bone mineral density by dual energy absorptiometry (DXA) requires adjustment for height (Ht). This is often not easily obtainable in nonambulant subjects. AIMS: To investigate the feasibility of using DXA images to evaluate measurements of Ht, sitting height (SH), and leg length (LL). METHODOLOGY: A total of 2 observers performed measurements of Ht, SH, and LL on 3 separate occasion using DXA digital images in 125 children. Intraclass correlation and relative technical error of measurement (rTEM) were performed to assess reliability of repeated measurements. In 25 children, Ht and SH were measured in clinic on the same day and Bland-Altman analysis was performed to compare DXA measured Ht, SH, LL with clinic measurements for these 25 children. RESULTS: Intraclass correlation for DXA based Ht, SH, and LL measurements ranged from 0.996 to 0.998 (p < 0.0001). rTEM of Ht, SH, and LL for observer 1 was 0.0016%, 0.002%, and 0.0034%, respectively. rTEM of Ht, SH, and LL between observer 1 and 2 was 0.0047%, 0.0049%, and 0.0087%, respectively. Mean difference between clinic and DXA measurements from Bland-Altman plots were +0.57 cm (95% confidence interval [CI] -0.54 to +1.68) for Ht, +1.33cm (-1.60 to +4.24) for SH, and -0.76cm (-3.88 to +2.37) for LL. CONCLUSIONS: Our study demonstrated for the first time that Ht, SH, and LL in children can be measured very precisely using DXA images. Ht can be measured accurately. We believe this may be a convenient method to obtain Ht measurements to allow size adjustment of DXA bone mineral density in immobile children with chronic conditions.

Prospective evaluation of plasma Epstein-Barr virus DNA clearance and fluorodeoxyglucose positron emission scan in assessing early response to chemotherapy in patients with advanced or recurrent nasopharyngeal carcinoma.

BACKGROUND: Plasma Epstein-Barr virus (pEBV) DNA and fluorodeoxyglucose positron emission (PET) reflect tumour burden in advanced NPC. This study hypothesised that a dual endpoint based on assessing pEBV DNA clearance and PET response could predict early drug response. METHODS: Eligible patients underwent a computed tomography (CT) scan and dual PET-CT at baseline, a PET-CT at 4 weeks, and then a CT scan at 10 weeks after starting palliative or induction chemotherapy. Plasma EBV DNA clearance was determined. RESULTS: Fifty-eight out of 70 enrolled patients completed all imaging and 50/58 had falling pEBV DNA level, which allowed calculation of the clearance. At a median follow-up of 29.1 months, the dual endpoint (pEBV DNA clearance ≤ 10 days and > 50% drop in sum of SUVmax of target lesions) was an independent indicator of overall survival (hazard ratio (HR) = 0.135, 95% CI = 0.039 to 0.466, p = 0.0015) and progression-free survival (HR = 0.136, 95% CI = 0.048 to 0.385, p = 0002). This dual endpoint could predict subsequent response by Response Evaluation Criteria In Solid Tumours (RECIST) criteria at 10 weeks after chemotherapy. CONCLUSIONS: Early PET-CT response and pEBV DNA clearance could predict survival and subsequent response. This dual endpoint is an innovative tool for assessing early drug response.

Identifying an early indicator of drug efficacy in patients with metastatic colorectal cancer-a prospective evaluation of circulating tumor cells, 18F-fluorodeoxyglucose positron-emission tomography and the RECIST criteria.

BACKGROUND: This study investigated the predictive and prognostic significance of assessing early drug response with both positron-emission computerized tomography (PET-CT) and circulating tumor cells (CTCs) in patients receiving first-line chemotherapy for metastatic colorectal cancer. PATIENTS AND METHODS: Eligible patients had PET-CT and CTC analysis at baseline and 4-6 weeks after starting chemotherapy, and then a CT scan at 10-12 weeks to assess the Response Evaluation Criteria In Solid Tumors (RECIST) response. Early response was defined as achieving a dual-endpoint consisting of PET-CT (30% drop in the sum of maximum standard uptake values-SUVmax-of target lesions) and CTC response (CTC < 3 cells/7.5 ml blood) at 4-6 weeks after starting chemotherapy. RESULTS: About 84 patients were enrolled with a median follow-up of 32.9 months (95% confidence interval, CI, 24.5 months-not reached, NR), and 70 patients (84.3%) completed all assessments. Achieving an early response based on the dual-endpoint was independently associated with progression-free survival (hazard ratio, HR = 0.452, 95% CI 0.267-0.765). The median progression-free survival of early responders was 7.41 months (95% CI, 6.05-9.11) compared with 5.37 months (95% CI, 4.68-6.24) in non-responders (log-rank, P = 0.0167). RECIST response at 10 weeks was independently associated with overall survival (OS) (HR = 0.484, 95% CI, 0.275-0.852). Early response based on the dual-endpoint could predict the subsequent RECIST response with a sensitivity, specificity and positive predictive value of 64%, 70% and 74%, respectively. CONCLUSIONS: Early response based on both PET-CT and CTC analysis has prognostic and probably predictive significance in patients undergoing first-line chemotherapy for metastatic colorectal cancer. Its utility as a new tool for assessing early drug response should be further validated.

Ear health and hearing surveillance in girls and women with Turner's syndrome: recommendations from the Turner's Syndrome Support Society.

BACKGROUND: Turner's syndrome (TS) is a common chromosomal disorder, affecting one in 2000 newborn girls, in which part or all of one X chromosome is missing. Ear and hearing problems are very common in girls and women with TS. The aim of this review was to review the published literature to suggest recommendations for otological health surveillance. METHOD: A keyword search of Ovid Medline was performed for published literature on the subject and evidence rated according to the GRADE criteria. RESULTS: Middle ear disorders are very common and persistent in girls and women with TS as are progressive sensorineural hearing loss and balance disorders. CONCLUSIONS: Otolaryngologists should be aware of the high prevalence and challenging nature of all forms of ear disease in individuals with TS. Early intervention may offer benefits to health and education, and we advocate routine lifelong annual hearing screening in this group.

Implications of MicroRNAs in the Treatment of Gefitinib-Resistant Non-Small Cell Lung Cancer.

Non-small cell lung cancer (NSCLC) represents about 85% of the reported cases of lung cancer. Acquired resistance to targeted therapy with epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib, is not uncommon. It is thus vital to explore novel strategies to restore sensitivity to gefitinib. Provided that microRNAs (miRNAs) negatively regulate their gene targets at the transcriptional level, it is speculated that miRNA mimetics may reduce the expression, activity and signal transduction of EGFR so that sensitization of tumour sites to gefitinib-induced cytotoxicity can be achieved. Indeed, a growing body of evidence has shown that the manipulation of endogenous levels of miRNA not only attenuates the EGFR/PI3K/Akt phosphorylation cascade, but also restores apoptotic cell death in in vitro models of experimentally-induced gefitinib resistance and provoked tumour regression/shrinkage in xenograft models. These data are in concordant with the clinical data showing that the differential expression profiles of miRNA in tumour tissues and blood associate strongly with drug response and overall survival. Furthermore, another line of studies indicate that the chemopreventive effects of a variety of natural compounds may involve miRNAs. The present review aims to discuss the therapeutic capacity of miRNAs in relation to recent discoveries on EGFR-TKI resistance, including chronic drug exposure and mutations.

Temperature- and sex-related effects of serine protease alleles on larval development in the Glanville fritillary butterfly.

The body reserves of adult Lepidoptera are accumulated during larval development. In the Glanville fritillary butterfly, larger body size increases female fecundity, but in males fast larval development and early eclosion, rather than large body size, increase mating success and hence fitness. Larval growth rate is highly heritable, but genetic variation associated with larval development is largely unknown. By comparing the Glanville fritillary population living in the Åland Islands in northern Europe with a population in Nantaizi in China, within the source of the post-glacial range expansion, we identified candidate genes with reduced variation in Åland, potentially affected by selection under cooler climatic conditions than in Nantaizi. We conducted an association study of larval growth traits by genotyping the extremes of phenotypic trait distributions for 23 SNPs in 10 genes. Three genes in clip-domain serine protease family were associated with larval growth rate, development time and pupal weight. Additive effects of two SNPs in the prophenoloxidase-activating proteinase-3 (ProPO3) gene, related to melanization, showed elevated growth rate in high temperature but reduced growth rate in moderate temperature. The allelic effects of the vitellin-degrading protease precursor gene on development time were opposite in the two sexes, one genotype being associated with long development time and heavy larvae in females but short development time in males. Sexually antagonistic selection is here evident in spite of sexual size dimorphism.

Use of fluoroquinolones is the single most important risk factor for the high bacterial load in patients with nasal and gastrointestinal colonization by multidrug-resistant Acinetobacter baumannii.

Gastrointestinal colonization by carbapenem-resistant Acinetobacter baumannii (CRAB) and multidrug-resistant Acinetobacter baumannii (MRAB) provides an important reservoir for clinical infections and hospital outbreaks. We conducted a 7-month study in a 3200-bed healthcare network to investigate the prevalence of gastrointestinal colonization of CRAB and MRAB in Hong Kong. Between 1 June and 31 December 2014, a total of 17,760 fecal specimens from 9469 patients were screened. Testing showed that 340 (1.9%) specimens from 224 (2.6%) patients were CRAB-positive, which included 70 (0.39%) MRAB-positive specimens from 54 (0.57%) patients. The presence of wound or ulcer, use of broad-spectrum antibiotics in the preceding 6 months, and residence in elderly homes are independent risk factors for gastrointestinal colonization of CRAB. Quantitative bacterial counts in various body sites (rectal, nasal, axilla, wound, catheterized urine, if available) were performed in 33 (61.1%) of 54 MRAB patients. Ten (30.3%) and 8 (24.2%) patients had high bacterial load (defined as over 3 log10) in rectal and nasal swabs, with a median of 5.04 log10 cfu/ml of rectal swab and 4.89 log10 cfu/ml of nasal swab in saline diluent, respectively. Nine (81.8%) of 11 patients with wounds had high bacterial load in wound swabs, with a median of 5.62 log10 cfu/ml. Use of fluoroquinolones 6 months before admission was the only significant factor associated with high bacterial load in nasal and rectal swabs. With the implementation of directly observed hand hygiene before meals and medications to all conscious hospitalized patients, no hospital outbreaks were observed during our study period.

Control of hospital endemicity of multiple-drug-resistant Acinetobacter baumannii ST457 with directly observed hand hygiene.

An increasing endemicity of multiple-drug-resistant Acinetobacter baumannii (MRAB) ST457 was noted in Hong Kong. The epidemiology, risk factors, and infection control measures to prevent nosocomial transmission of this epidemic clone were analyzed. A total of 5,058 patients cultured positive with A. baumannii between 1 January 2004 and 30 June 2014 were included, of which 297 (5.9 %) had bacteremia. The first case of MRAB bacteremia emerged in 2009, with an incidence that increased from 0.27 (one case) in 2009 to 1.86 (14 cases) per 100,000 patient-days in 2013 (p < 0.001). With the implementation of strict contact precautions and directly observed hand hygiene in conscious patients immediately before receiving meals and medications in July 2013, the incidence of MRAB bacteremia reduced from its peak to 0.77 (one case) per 100,000 patient-days in the first 6 months of 2014 (p < 0.001). Patients from long-term care facilities for the elderly [odds ratio (OR) 18.6, confidence interval (CI) 2.1-162.4, p = 0.008] and history of carbapenem (OR 7.0, CI 1.7-28.0, p = 0.006) and beta-lactam/beta-lactamase use (OR 5.6, CI 1.1-28.7, p = 0.038) 90 days prior to admission were independent risk factors for MRAB bacteremia by logistic regression when compared with carbapenem-susceptible A. baumannii bacteremia.

Containment of Clostridium difficile infection without reduction in antimicrobial use in Hong Kong.

Clostridium difficile ribotype 002 with hypersporulating capacity has been increasingly identified in Hong Kong. Proactive infection control measures are important to prevent the establishment of endemicity of C. difficile ribotype 002. A total of 329 patients with healthcare-associated C. difficile infection (CDI) were recruited in our healthcare network between 1 January 2008 and 30 June 2012 in this study. The incidence rates of healthcare-associated CDI per 10,000 admissions and 10,000 patient-days increased significantly by 15.3 and 17.0%, respectively, per quarter (p < 0.001) from 2008 1Q to 2010 1Q by segmented Poisson regression. With the full implementation of enhanced infection control interventions, there was an immediate significant reduction in both healthcare-associated CDI rates per 10,000 admissions and per 10,000 patient-days by 47% (p < 0.001) in 2010 2Q, followed by a further decline of CDI per 10,000 admissions and CDI per 10,000 patient-days by -19.4 and -19.8% from 2010 2Q to 2012 2Q, respectively (p < 0.001), despite a replacement of hand washing with soap and water by alcohol-based hand rub in the healthcare network. The proportion of C. difficile ribotype 002 was not statistically different (34/177, 19.2% vs. 25/152, 16.4%, p = 0.515), and the consumption of broad-spectrum antibiotics presented as divided daily dose per 1,000 acute bed-day occupancy per quarter remained unchanged (140.9 vs. 152.3) before and after infection control interventions. Our results suggested that the reduction of healthcare-associated CDI was attributable to infection control interventions instead of replacement of ribotypes or reduction in antimicrobial selective pressure.

The inflammatory milieu and the insulin like growth factor axis in children with inflammatory bowel disease following recombinant human growth hormone treatment.

It is unclear whether recombinant human growth hormone (rhGH) in inflammatory bowel disease (IBD) alters cytokine profile. The objective of this study is to evaluate changes in cytokines and systemic markers of the insulin growth factor axis following 6 months of rhGH treatment in children with IBD. In a six-month randomised control trial in children with IBD treated with rhGH at 0.067 mg/kg/day and controls (11 in each group), we measured pro-, anti-inflammatory cytokines and systemic markers of the IGF axis (total IGF-1, free IGF-1, total IGFBP-3, ALS, IGFBP-2) at baseline (T+0), and six months (T+6). Results expressed as median (range). In the rhGH group, TNFα was 3.1pg/ml (2.9, 100.6) and 3.6pg/ml (3.1, 5.3) at T+0 and T+6, respectively (p=0.85), whereas in the controls this was 3.3pg/ ml (2.7, 4.0) and 3.1pg/m l (2.7, 4.7), respectively (p=0.79). In the rhGH group, IL1ß was 18.0pg/ml (5.0,716.7) and 18.0pg/ml (1.7, 52.2) at T+0 and T+6 respectively(p=0.90), whereas in the controls this was 19.8pg/ml (4.1, 27.1) and 19.1pg/ml (2.4,77.3), respectively (p=0.65). None of the twenty-eight other cytokines analysed was different at T+6 in either group. Despite increase in total IGF1 in the rhGH group (p=0.03), free IGF1, IGFBP3, ALS and IGFBP2 did not change in either group at T+6. Percentage change in IGFBP3, was significantly associated with percentage change in IL2 (r=0.77, p=0.009) and IL4 (r=0.58, p=0.01). Percentage change in ALS was significantly associated with percentage change in IL2 (r=0.90, p less than 0.0001) and IL4 (r=0.63, p=0.04). Although changes in markers of the GH/IGF-1 axis do show an association with cytokines (IL-2, IL-4) in pediatric IBD, six months of rhGH treatment was not associated with any significant changes in levels of a range of pro and anti-inflammatory cytokine. Careful evaluation of disease process is required in future trials of rhGH in paediatric IBD.

PubMed-supported clinical term weighting approach for improving inter-patient similarity measure in diagnosis prediction.

BACKGROUND: Similarity-based retrieval of Electronic Health Records (EHRs) from large clinical information systems provides physicians the evidence support in making diagnoses or referring examinations for the suspected cases. Clinical Terms in EHRs represent high-level conceptual information and the similarity measure established based on these terms reflects the chance of inter-patient disease co-occurrence. The assumption that clinical terms are equally relevant to a disease is unrealistic, reducing the prediction accuracy. Here we propose a term weighting approach supported by PubMed search engine to address this issue. METHODS: We collected and studied 112 abdominal computed tomography imaging examination reports from four hospitals in Hong Kong. Clinical terms, which are the image findings related to hepatocellular carcinoma (HCC), were extracted from the reports. Through two systematic PubMed search methods, the generic and specific term weightings were established by estimating the conditional probabilities of clinical terms given HCC. Each report was characterized by an ontological feature vector and there were totally 6216 vector pairs. We optimized the modified direction cosine (mDC) with respect to a regularization constant embedded into the feature vector. Equal, generic and specific term weighting approaches were applied to measure the similarity of each pair and their performances for predicting inter-patient co-occurrence of HCC diagnoses were compared by using Receiver Operating Characteristics (ROC) analysis. RESULTS: The Areas under the curves (AUROCs) of similarity scores based on equal, generic and specific term weighting approaches were 0.735, 0.728 and 0.743 respectively (p < 0.01). In comparison with equal term weighting, the performance was significantly improved by specific term weighting (p < 0.01) but not by generic term weighting. The clinical terms "Dysplastic nodule", "nodule of liver" and "equal density (isodense) lesion" were found the top three image findings associated with HCC in PubMed. CONCLUSIONS: Our findings suggest that the optimized similarity measure with specific term weighting to EHRs can improve significantly the accuracy for predicting the inter-patient co-occurrence of diagnosis when compared with equal and generic term weighting approaches.

Exploring microRNA-mediated alteration of EGFR signaling pathway in non-small cell lung cancer using an mRNA:miRNA regression model supported by target prediction databases.

EGFR signaling pathway and microRNAs (miRNAs) are two important factors for development and treatment in non-small cell lung cancer (NSCLC). Microarray analysis enables the genome-wide expression profiling. However, the information from microarray data may not be fully deciphered through the existing approaches. In this study we present an mRNA:miRNA stepwise regression model supported by miRNA target prediction databases. This model is applied to explore the roles of miRNAs in the EGFR signaling pathway. The results show that miR-145 is positively associated with epidermal growth factor (EGF) in the pre-surgery NSCLC group and miR-199a-5p is positively associated with EGF in the post-surgery NSCLC group. Surprisingly, miR-495 is positively associated with protein tyrosine kinase 2 (PTK2) in both groups. The coefficient of determination (R(2)) and leave-one-out cross-validation (LOOCV) demonstrate good performance of our regression model, indicating that it can identify the miRNA roles as oncomirs and tumor suppressor mirs in NSCLC.

Cytochrome P450 gene CYP337 and heritability of fitness traits in the Glanville fritillary butterfly.

Fitness-related life history traits often show substantial heritable genetic variation in natural populations, but knowledge of the genetic architecture of these traits is limited. In the Glanville fritillary butterfly, we measured the heritability of key life history traits in a large outdoor population cage during 2 years and generations and combined this experiment with an association study of a set of candidate genes. The genes were selected on the basis of previous genomic and transcriptomic studies and have been linked to the physiology and life history of this or other arthropod species. Heritability was high and significant for two traits, post-diapause larval development time (h(2) = 0.37) and lifetime egg (and larval) production (h(2) = 0.62); the latter is closely related to lifetime reproductive success and therefore fitness. We discovered a strong association between genetic polymorphism in the cytochrome P450 gene CYP337 and lifetime egg production, which accounted for 14% of the additive variance in egg production. This gene belongs to a group of cytochrome P450 genes that have a well-documented role in host plant adaptations in Lepidoptera and other insects and is likely to play an important role in the ecology and microevolution of the Glanville fritillary. This study provides a prime example of a gene associated with heritable fitness variation, measured under semi-natural ecological conditions.

Unraveling the causes of the Seoul Halloween crowd-crush disaster.

As the world steadily recovers from the COVID-19 pandemic, managing large gatherings becomes a critical concern for ensuring crowd safety. The crowd-crush disaster in Seoul in 2022 highlights the need for effective predictive crowd management techniques. In this study, an empirical analysis of this incident is conducted using data from various sources, and model-based simulations are created to replicate hazardous crowd conditions in high-risk areas. In the empirical analysis, mobile device data indicates a significant increase in population above normal levels in the disaster area just hours before the incident occurred. In the simulations, a hydrodynamic model is employed to simulate a bidirectional collision, which quantitatively demonstrates that the average density during the crush reached 7.57 ped/m2 (with a maximum of (9.95)ped/m2). Additionally, the average crowd pressure peaked at 1,063 N/m (with a maximum of 1,961 N/m), and the maximum velocity entropy was 10.99. Based on these findings, it can be concluded that the primary causes of the disaster were the substantial population, bidirectional collision, and escalating panic. The results of controlled simulations under various management strategies are then presented. By implementing effective crowd management techniques, crowd safety can be enhanced through quantitative comparisons of these key indicators.

Air dispersal of multi-drug-resistant organisms including meticillin-resistant Staphylococcus aureus, carbapenem-resistant Acinetobacter baumannii and carbapenemase-producing Enterobacterales in general wards: surveillance culture of air grilles.

BACKGROUND: The environmental surveillance of air grilles in clinical areas has not been systematically analysed. METHODS: Samples were collected from frequently touched items (N = 529), air supply (N = 295) and exhaust (N = 184) grilles in six medical and 11 surgical wards for the cultures of multi-drug-resistant organisms (MDROs): meticillin-resistant Staphylococcus aureus (MRSA), carbapenem-resistant Acinetobacter baumannii (CRAB) and carbapenemase-producing Enterobacterales (CPE), and isolates were selected for whole-genome sequencing (WGS). The contamination rates were correlated with the colonization pressures of the respective MDROs. RESULTS: From 3rd October to 21st November 2023, 9.8% (99/1008) of the samples tested positive, with MRSA (24.2%, 24/99), CRAB (59.6%, 59/99) and CPE (2.0%, 2/99), being the only detected MDROs. The contamination rate in air exhaust grilles (26.6%, 49/184) was significantly higher than in air supply grilles (5.8%, 17/295; P<0.001). The contamination rate of air exhaust grilles with any MDRO in acute medical wards (73.7%, 14/19) was significantly higher than in surgical wards (12.5%, 4/32; P<0.001). However, there was no difference in the contamination rate of air exhaust grilles between those located inside and outside the cohort cubicles for MDROs (27.1%, 13/48 vs 28.8%, 30/104; P=0.823). Nevertheless, the weekly CRAB colonization pressure showed a significant correlation with the overall environmental contamination rate (r = 0.878; 95% confidence interval (CI): 0.136-0.986; P=0.004), as well as with the contamination rate in air supply grilles (r = 0.960; 95% CI: 0.375-0.999; P<0.001) and air exhaust grilles (r = 0.850; 95% CI: 0.401-0.980; P=0.008). WGS demonstrated clonal relatedness of isolates collected from patients and air exhaust grilles. CONCLUSIONS: Air grilles may serve as MDRO reservoirs. Cohort nursing in open cubicles may not completely prevent MDRO transmission through air dispersal, prompting the consideration of future hospital design.