Pten regulates endocytic trafficking of cell adhesion and Wnt signaling molecules to pattern the retina

The retina is exquisitely patterned, with neuronal somata positioned at regular intervals to completely sample the visual field. Here, we show that phosphatase and tensin homolog (Pten) controls starburst amacrine cell spacing by modulating vesicular trafficking of cell adhesion molecules and Wnt proteins. Single-cell transcriptomics and double-mutant analyses revealed that Pten and Down syndrome cell adhesion molecule Dscam) are co-expressed and function additively to pattern starburst amacrine cell mosaics. Mechanistically, Pten loss accelerates the endocytic trafficking of DSCAM, FAT3, and MEGF10 off the cell membrane and into endocytic vesicles in amacrine cells. Accordingly, the vesicular proteome, a molecular signature of the cell of origin, is enriched in exocytosis, vesicle-mediated transport, and receptor internalization proteins in Pten conditional knockout (PtencKO) retinas. Wnt signaling molecules are also enriched in PtencKO retinal vesicles, and the genetic or pharmacological disruption of Wnt signaling phenocopies amacrine cell patterning defects. Pten thus controls vesicular trafficking of cell adhesion and signaling molecules to establish retinal amacrine cell mosaics.

Increasing Neurofilament and Glial Fibrillary Acidic Protein After Treatment Discontinuation Predicts Multiple Sclerosis Disease Activity

BACKGROUND AND OBJECTIVES

Stable patients with multiple sclerosis (MS) may discontinue treatment, but the risk of disease activity is unknown. Serum neurofilament light chain (sNfL) and serum glial fibrillary acidic protein (sGFAP) are biomarkers of subclinical disease activity and may help risk stratification. In this study, sNfL and sGFAP levels in stable patients were evaluated before and after treatment discontinuation to determine association with disease activity.

METHODS

This observational study included patients enrolled in the Comprehensive Longitudinal Investigation in MS at the Brigham and Women's Hospital who discontinued treatment after >2 years disease activity-free. Two serum samples within 2 years, before and after treatment stop, were sent for sNfL and sGFAP measurements by single-molecule array. Biannual neurologic examinations and yearly MRI scans determined disease activity by 3 time-to-event outcomes: 6-month confirmed disability worsening (CDW), clinical attacks, and MRI activity (new T2 or contrast-enhancing lesions). Associations between each outcome and log-transformed sNfL and sGFAP levels pretreatment stop and posttreatment stop and the percent change were estimated using multivariable Cox regression analysis adjusting for age, disability, disease duration, and duration from attack before treatment stop.

RESULTS

Seventy-eight patients (92% female) discontinued treatment at a median (interquartile range) age of 48.5 years (39.0-55.7) and disease duration of 12.3 years (7.5-18.8) and were followed up for 6.3 years (4.2-8.5). CDW occurred in 27 patients (35%), new attacks in 19 (24%), and new MRI activity in 26 (33%). Higher posttreatment stop sNfL level was associated with CDW (adjusted hazard ratio (aHR) 2.80, 95% CI 1.36-5.76, p = 0.005) and new MRI activity (aHR 3.09, 95% CI 1.42-6.70, p = 0.004). Patients who had >100% increase in sNfL level from pretreatment stop to posttreatment stop had greater risk of CDW (HR 3.87, 95% CI 1.4-10.7, p = 0.009) and developing new MRI activity (HR 4.02, 95% CI 1.51-10.7, p = 0.005). Patients who had >50% increase in sGFAP level also had greater risk of CDW (HR 5.34, 95% CI 1.4-19.9, p = 0.012) and developing new MRI activity (HR 5.16, 95% CI 1.71-15.6, p = 0.004).

DISCUSSION

Stable patients who discontinue treatment may be risk stratified by sNfL and sGFAP levels measured before and after discontinuing treatment. Further studies are needed to validate findings and determine whether resuming treatment in patients with increasing biomarker levels reduces risk of subsequent disease activity.

Clinical validation of a multi-protein, serum-based assay for disease activity assessments in multiple sclerosis

An 18-protein multiple sclerosis (MS) disease activity (DA) test was validated based on associations between algorithm scores and clinical/radiographic assessments (N = 614 serum samples; Train [n = 426; algorithm development] and Test [n = 188; evaluation] subsets). The multi-protein model was trained based on presence/absence of gadolinium-positive (Gd+) lesions and was also strongly associated with new/enlarging T2 lesions, and active versus stable disease (composite of radiographic and clinical evidence of DA) with improved performance (p < 0.05) compared to the neurofilament light single protein model. The odds of having ≥1 Gd + lesions with a moderate/high DA score were 4.49 times that of a low DA score, and the odds of having ≥2 Gd + lesions with a high DA score were 20.99 times that of a low/moderate DA score. The MSDA Test was clinically validated with improved performance compared to the top-performing single-protein model and can serve as a quantitative tool to enhance the care of MS patients.

Early neurofilament light and glial fibrillary acidic protein levels improve predictive models of multiple sclerosis outcomes

BACKGROUND

Early risk-stratification in multiple sclerosis (MS) may impact treatment decisions. Current predictive models have identified that clinical and imaging characteristics of aggressive disease are associated with worse long-term outcomes. Serum biomarkers, neurofilament (sNfL) and glial fibrillary acidic protein (sGFAP), reflect subclinical disease activity through separate pathological processes and may contribute to predictive models of clinical and MRI outcomes.

METHODS

We conducted a retrospective analysis of the Comprehensive Longitudinal Investigation of Multiple Sclerosis at the Brigham and Women's Hospital (CLIMB study), where patients with multiple sclerosis are seen every 6 months and undergo Expanded Disability Status Scale (EDSS) assessment, have annual brain MRI scans where volumetric analysis is conducted to calculate T2-lesion volume (T2LV) and brain parenchymal fraction (BPF), and donate a yearly blood sample for subsequent analysis. We included patients with newly diagnosed relapsing-remitting MS and serum samples obtained at baseline visit and 1-year follow-up (both within 3 years of onset), and were assessed at 10-year follow-up. We measured sNfL and sGFAP by single molecule array at baseline visit and at 1-year follow-up. A predictive clinical model was developed using age, sex, Expanded Disability Status Scale (EDSS), pyramidal signs, relapse rate, and spinal cord lesions at first visit. The main outcome was odds of developing of secondary progressive (SP)MS at year 10. Secondary outcomes included 10-year EDSS, brain T2LV and BPF. We compared the goodness-of-fit of the predictive clinical model with and without sNfL and sGFAP at baseline and 1-year follow-up, for each outcome by area under the receiver operating characteristic curve (AUC) or R-squared.

RESULTS

A total 144 patients with median MS onset at age 37.4 years (interquartile range: 29.4-45.4), 64% female, were included. SPMS developed in 25 (17.4%) patients. The AUC for the predictive clinical model without biomarker data was 0.73, which improved to 0.77 when both sNfL and sGFAP were included in the model (P = 0.021). In this model, higher baseline sGFAP associated with developing SPMS (OR=3.3 [95%CI:1.1,10.6], P = 0.04). Adding 1-year follow-up biomarker levels further improved the model fit (AUC = 0.79) but this change was not statistically significant (P = 0.15). Adding baseline biomarker data also improved the R-squared of clinical models for 10-year EDSS from 0.24 to 0.28 (P = 0.032), while additional 1-year follow-up levels did not. Baseline sGFAP was associated with 10-year EDSS (ß=0.58 [95%CI:0.00,1.16], P = 0.05). For MRI outcomes, baseline biomarker levels improved R-squared for T2LV from 0.12 to 0.27 (P<0.001), and BPF from 0.15 to 0.20 (P = 0.042). Adding 1-year follow-up biomarker data further improved T2LV to 0.33 (P = 0.0065) and BPF to 0.23 (P = 0.048). Baseline sNfL was associated with T2LV (ß=0.34 [95%CI:0.21,0.48], P<0.001) and 1-year follow-up sNfL with BPF (ß=-2.53% [95%CI:-4.18,-0.89], P = 0.003).

CONCLUSIONS

Early biomarker levels modestly improve predictive models containing clinical and MRI variables. Worse clinical outcomes, SPMS and EDSS, are associated with higher sGFAP levels and worse MRI outcomes, T2LV and BPF, are associated with higher sNfL levels. Prospective study implementing these predictive models into clinical practice are needed to determine if early biomarker levels meaningfully impact clinical practice.

Differences in in-hospital outcomes and healthcare utilization for laparoscopic versus open approach for emergency inguinal hernia repair: a nationwide analysis

PURPOSE

There has been a growing debate of whether laparoscopic or open surgical techniques are superior for inguinal hernia repair. For incarcerated and strangulated inguinal hernias, the laparoscopic approach remains controversial. This study aims to be the first nationwide analysis to compare clinical and healthcare utilization outcomes between laparoscopic and open inguinal hernia repair in an emergency setting.

METHODS

A retrospective analysis of the National Inpatient Sample was performed. All patients who underwent laparoscopic inguinal hernia repair (LIHR) and open inguinal hernia repair (OIHR) between October 2015 and December 2019 were included. The primary outcome was mortality, and secondary outcomes include post-operative complications, ICU admission, length of stay (LOS), and total admission cost. Two approaches were compared using univariate and multivariate logistic and linear regression.

RESULTS

Between the years 2015 and 2019, 17,205 patients were included. Among these, 213 patients underwent LIHR and 16,992 underwent OIHR. No difference was observed between laparoscopic and open repair for mortality (odds ratio [OR] 0.80, 95% CI [0.25, 2.61], p = 0.714). Additionally, there was no significant difference between groups for post-operative ICU admission (OR 1.11, 95% CI [0.74, 1.67], p = 0.614), post-operative complications (OR 1.09, 95% CI [0.76, 1.56], p = 0.647), LOS (mean difference [MD]: -0.02 days, 95% CI [- 0.56, 0.52], p = 0.934), or total admission cost (MD: $3,028.29, 95% CI [$- 110.94, $6167.53], p = 0.059).

CONCLUSION

Laparoscopic inguinal hernia repair is comparable to the open inguinal hernia repair with respect to low rates of morbidity, mortality as well as healthcare resource utilization.

Ascl1 phospho-site mutations enhance neuronal conversion of adult cortical astrocytes in vivo

Direct neuronal reprogramming, the process whereby a terminally differentiated cell is converted into an induced neuron without traversing a pluripotent state, has tremendous therapeutic potential for a host of neurodegenerative diseases. While there is strong evidence for astrocyte-to-neuron conversion in vitro, in vivo studies in the adult brain are less supportive or controversial. Here, we set out to enhance the efficacy of neuronal conversion of adult astrocytes in vivo by optimizing the neurogenic capacity of a driver transcription factor encoded by the proneural gene Ascl1. Specifically, we mutated six serine phospho-acceptor sites in Ascl1 to alanines (Ascl1SA6) to prevent phosphorylation by proline-directed serine/threonine kinases. Native Ascl1 or Ascl1SA6 were expressed in adult, murine cortical astrocytes under the control of a glial fibrillary acidic protein (GFAP) promoter using adeno-associated viruses (AAVs). When targeted to the cerebral cortex in vivo, mCherry+ cells transduced with AAV8-GFAP-Ascl1SA6-mCherry or AAV8-GFAP-Ascl1-mCherry expressed neuronal markers within 14 days post-transduction, with Ascl1SA6 promoting the formation of more mature dendritic arbors compared to Ascl1. However, mCherry expression disappeared by 2-months post-transduction of the AAV8-GFAP-mCherry control-vector. To circumvent reporter issues, AAV-GFAP-iCre (control) and AAV-GFAP-Ascl1 (or Ascl1SA6)-iCre constructs were generated and injected into the cerebral cortex of Rosa reporter mice. In all comparisons of AAV capsids (AAV5 and AAV8), GFAP promoters (long and short), and reporter mice (Rosa-zsGreen and Rosa-tdtomato), Ascl1SA6 transduced cells more frequently expressed early- (Dcx) and late- (NeuN) neuronal markers. Furthermore, Ascl1SA6 repressed the expression of astrocytic markers Sox9 and GFAP more efficiently than Ascl1. Finally, we co-transduced an AAV expressing ChR2-(H134R)-YFP, an optogenetic actuator. After channelrhodopsin photostimulation, we found that Ascl1SA6 co-transduced astrocytes exhibited a significantly faster decay of evoked potentials to baseline, a neuronal feature, when compared to iCre control cells. Taken together, our findings support an enhanced neuronal conversion efficiency of Ascl1SA6 vs. Ascl1, and position Ascl1SA6 as a critical transcription factor for future studies aimed at converting adult brain astrocytes to mature neurons to treat disease.

Targeted elimination of species-rich larval habitats can rapidly collapse arbovirus vector mosquito populations at hotel compounds in Zanzibar

Understanding the dynamics of larval habitat utilization by mosquito communities is crucial for the design of efficient environmental control strategies. The authors investigated the structure of mosquito communities found at hotel compounds in Zanzibar, networks of mosquito interactions with larval habitats and robustness of mosquito communities to elimination of larval habitats. A total of 23 698 mosquitoes comprising 26 species in six genera were found. Aedes aegypti (n = 16 207), Aedes bromeliae/Aedes lillie (n = 1340), Culex quinquefasciatus (n = 1300) and Eretmapodites quinquevitattus (n = 659) were the most dominant species. Ecological network analyses revealed the presence of dominant, larval habitat generalist species (e.g., A. aegypti), exploiting virtually all types of water holding containers and few larval habitat specialist species (e.g., Aedes natalensis, Orthopodomyia spp). Simulations of mosquito community robustness to systematic elimination of larval habitats indicate that mosquito populations are highly sensitive to elimination of larval habitats sustaining higher mosquito species diversity. This study provides insights on potential foci of future mosquito-borne arboviral disease outbreaks in Zanzibar and underscores the need for detailed knowledge on the ecological function of larval habitats for effective mosquito control by larval sources management.

An Outbreak of Arboviral Infection in a Region with Background Malaria Endemicity from Northwestern Nigeria: An Investigation Report

INTRODUCTION

Arboviruses are a group of infectious agents transmitted by blood-sucking arthropods from one vertebrate host to another. The agents include Dengue fever and West Nile Virus, amongst others. However, Dengue fever is now the world's fastest-spreading tropical disease, with the annual number of cases increasing 30-fold in the last 50 years. Cases of an unknown febrile illness were reported in Sokoto, northwestern Nigeria, in the last quarter of 2016. We investigated to verify the existence of the outbreak and described the socio-demographic characteristics and management outcome of the cases seen.

METHODS

We conducted a descriptive, cross-sectional study and an analytical case control study. For the descriptive study, we defined suspected and confirmed cases of outbreak using established protocol. Cases were identified using stimulated passive and active surveillance. For each suspected case, we collected information on age, sex, residence and time of onset. We described the outbreak by time, place and person. Blood specimens were collected and submitted to the reference laboratory for detection of viral agents. We conducted a case-control study with 185 cases and 370 controls. Information on the socio-demographics and risk factors for arboviral infection and malaria among the cases and controls was collected.

RESULTS

The outbreak of febrile illness in Sokoto started on the 3rd of October, 2016. A total 1477 cases were line listed (3rd Oct-11th November 2016) and 16 deaths (case fatality rate: 1.1% reported). The most affected areas were urban slums in two urban Local Government Areas (LGA) - Sokoto North and Sokoto South. Laboratory analysis revealed Dengue, West Nile and Malaria in increasing order from the representative samples. There were 57 (43.2%) respondents in the age-group 21-30 among the cases, while 99 (53.5%) of them were males. Cases living in a bushy neighborhood (OR=1.6, 95% CI=1.1-2.4), keeping waste bins in their houses (OR=1.5, 95% CI=1.0-2.1), having uncovered well or uncovered water containers (OR=3.6, 95% CI=2.1- 6.0) were more likely to develop arboviral infection or malaria compared to controls. Having window nets (OR=0.3, 95% CI=0.2-0.5) was found to be a protective factor against arboviral infection or malaria among the cases.

CONCLUSIONS

The outbreak of febrile illness in Sokoto was linked to arboviral agents (Dengue virus and West Nile virus) in a malaria-endemic zone. We draw attention to the fact that arboviral infections can coexist with malaria in our region especially in an outbreak setting.

Extraction of chitin from edible crab shells of Callinectes sapidus and comparison with market purchased chitin

Chitin and its derived products have immense economic value due to their vital role in various biological activities as well as biomedical and industrial application. Insects, microorganism and crustaceans are the main supply of chitin but the crustaceans shell like shrimp, krill, lobsters and crabs are the main commercial sources. Chitin content of an individual varies depending on the structures possessing the polymer and the species. In this study edible crabs' shells (Callinectes sapidus) were demineralized and deproteinized resulting in 13.8% (dry weight) chitin recovery from chitin wastes. FTIR and XRD analyses of the experimental crude as well as purified chitins revealed that both were much comparable to the commercially purchased controls. The acid pretreatment ceded 54g of colloidal chitin that resulted in 1080% of the crude chitin. The colloidal chitin was exploited for isolation of eighty five chitinolytic bacterial isolates from different sources. Zone of clearance was displayed by the thirty five isolates (41.17%) succeeding their growth at pH 7 on colloidal chitin agar medium. Maximum chitinolytic activity i.e. 301.55 U/ml was exhibited by isolate JF70 when cultivated in extracted chitin containing both carbon and nitrogen. The study showed wastes of blue crabs can be utilized for extraction of chitin and isolation of chitinolytic bacteria that can be used to degrade chitin waste, resolve environmental pollution as well as industrial purpose.

Validation of Two Kinetic Assays for the Quantification of Endotoxin in Human Serum

Background: There is an emerging evidence of the role of the microbiome in neurological diseases. Endotoxin is a component of gram-negative bacteria and thought to be one of the possible signals between the gut microbiota and the immune system. Previous studies explored the blood levels of endotoxin using an endpoint chromogenic assay. Methods: We validated and compared the analytical performance of two kinetic assays for the quantification of endotoxin in serum: (1) the Limulus Amebocyte Lysate (LAL) Kinetic-QCL assay and (2) the turbidimetric LAL Pyrogent-5000 assay. We used the best-performing validated assay to measure the endotoxin level in 20 patients with multiple sclerosis (MS) and eight healthy controls. Results: The Pyrogent-5000 and QCL assay achieved similar performance in regard to spike recovery and linear dilution; however, the Pyrogent-5000 had a better signal to noise in the calibrator curve. By using the Pyrogent-5000 assay, we found that serum samples from MS patients and healthy controls have a similar level of endotoxin; hence, we did not find evidence to support a penetration of endotoxin in the blood of MS patients. Our findings do not exclude a role of endotoxin in mediating signals from the gut microbiota in MS patients directly at the gut-blood barrier where numerous antigen-presenting cells are actively sensing metabolites and bacterial products.

Serum neurofilament levels and patient-reported outcomes in multiple sclerosis

OBJECTIVE

Serum neurofilament light (sNfL) is a promising new biomarker in multiple sclerosis (MS). We explored the relationship between sNfL and health outcomes and resource use in MS patients.

METHODS

MS patients with serum samples and health-outcome measurements collected longitudinally between 2011 and 2016 were analyzed. sNfL values were evaluated across age and gender. Data were analyzed using correlation with log-transformed sNfL values.

RESULTS

A total of 304 MS patients with a mean age of 32.9 years, average EDSS of 1.6 (SD = 1.5) and baseline sNfL of 8.8 (range 1.23-78.3) pg/mL were studied. Baseline sNFL values increased with age and were higher in females. Baseline sNfL correlated with baseline Multiple Sclerosis Quality of Life physical composite (mean = 49.4 (9.1), P = 0.035) and baseline EDSS (P = 0.002). Other PRO measures at baseline did not show a significant relationship with baseline sNfL. Average of baseline and follow-up sNfL correlated with MSQoL physical-role limitations (mean = 48.9 (10.8), P = 0.043) and social-functioning (mean = 52.3 (7), P = 0.034) at 24-month follow-up. We found a trend for numerically higher sNfL levels in nonpersistent patients compared to those who were persistent to treatment (11.13 vs. 8.53 pg/mL, P = 0.093) measured as average of baseline and 24-month values. Baseline NfL was associated with number of intravenous steroid infusions (mean = 0.2; SD = 3.0, P = 0.013), whereas the average of baseline and 12 months NfL values related to inpatient stays at 12 months (mean = 0.2; SD = 3.0 P = 0.053).

CONCLUSION

Serum NfL is a patient-centric biomarker that correlated with MS patient health-outcomes and healthcare utilization measures in a real-world cohort.

Descriptive epidemiology of coronavirus disease 2019 in Nigeria, 27 February-6 June 2020

The objective of this study was to describe the epidemiology of COVID-19 in Nigeria with a view of generating evidence to enhance planning and response strategies. A national surveillance dataset between 27 February and 6 June 2020 was retrospectively analysed, with confirmatory testing for COVID-19 done by real-time polymerase chain reaction (RT-PCR). The primary outcomes were cumulative incidence (CI) and case fatality (CF). A total of 40 926 persons (67% of total 60 839) had complete records of RT-PCR test across 35 states and the Federal Capital Territory, 12 289 (30.0%) of whom were confirmed COVID-19 cases. Of those confirmed cases, 3467 (28.2%) had complete records of clinical outcome (alive or dead), 342 (9.9%) of which died. The overall CI and CF were 5.6 per 100 000 population and 2.8%, respectively. The highest proportion of COVID-19 cases and deaths were recorded in persons aged 31-40 years (25.5%) and 61-70 years (26.6%), respectively; and males accounted for a higher proportion of confirmed cases (65.8%) and deaths (79.0%). Sixty-six per cent of confirmed COVID-19 cases were asymptomatic at diagnosis. In conclusion, this paper has provided an insight into the early epidemiology of COVID-19 in Nigeria, which could be useful for contextualising public health planning.

Comparative analysis of immune cell subsets in peripheral blood from patients with periodontal disease and healthy controls

Periodontitis is a chronic inflammatory disease caused by the colonization of teeth by the bacterial plaque biofilm and the resultant host immune responses in adjacent periodontal tissues. Disease severity can vary dramatically between patients with periodontitis, with some subjects displaying inflammation without bony destruction (gingivitis), while others experience chronic progressive or rapidly aggressive gingival connective tissue damage and bone loss. To determine whether peripheral immune dysregulation is associated with periodontitis, we performed extensive analysis of immune cell subsets in peripheral blood from patients with chronic or aggressive periodontitis versus periodontally healthy control subjects. Peripheral blood mononuclear cells (PBMC) from patients with chronic periodontitis or aggressive periodontitis and from periodontally healthy controls were analysed by 8-10-colour flow cytometry for the frequencies of various lymphocyte subsets, including interleukin (IL)-17-, interferon (IFN)-γ-, tumour necrosis factor (TNF)-α- and IL-10-producing cells, and the frequencies and phenotype of monocytes. Cytokine levels in serum from the different groups were determined by Luminex assay. We found no significant differences in the frequencies of major immune cell populations [CD4⁺ T cells, CD8⁺ T cells, γδ T cells, CD4⁺ CD45RO⁺ CD25⁺ CD127^low regulatory T cells (T_regs ), CD19⁺ B cells, CD14⁺ monocytes] or of cytokine-producing T cells, or in the phenotype of CD14⁺ monocytes in peripheral blood from these patient cohorts. Additionally, no significant differences were observed in serum levels of prototypical inflammatory cytokines. These results suggest that the local gingival inflammatory response is not reflected by obvious changes in major blood immune cell subset frequencies.

Geographic and socioeconomic factors affecting delivery of bariatric surgery across high- and low-utilization healthcare systems

Background

In countries with universal health coverage, the delivery of care should be driven by need. However, other factors, such as proximity to local facilities or neighbourhood socioeconomic status, may be more important. The objective of this study was to evaluate which geographic and socioeconomic factors affect the delivery of bariatric care in Canada.

Methods

This was a national retrospective cohort study of all adult patients undergoing bariatric surgery between April 2008 and March 2015 in Canada (excluding Quebec). The main outcome was neighbourhood rate of bariatric surgery per 1000 obese individuals (BMI over 30 kg/m2). Geographic cluster analysis and multilevel ordinal logistic regression were used to identify high-use clusters, and to evaluate the effect of geographic and socioeconomic factors on care delivery.

Results

Having a bariatric facility within the same public health unit as the neighbourhood was associated with a 6·6 times higher odds of being in a bariatric high-use cluster (odds ratio (OR) 6·60, 95 per cent c.i. 1·90 to 22·88; P = 0·003). This finding was consistent across provinces after adjusting for utilization rates. Neighbourhoods with higher obesity rates were also more likely to be within high-use clusters (OR per 5 per cent increase: 2·95, 1·54 to 5·66; P = 0·001), whereas neighbourhoods closer to bariatric centres were less likely to be (OR per 50 km: 0·91, 0·82 to 1·00; P = 0·048).

Conclusion

In this study, across provincial healthcare systems with high and low utilization, the delivery of care was driven by the presence of local facilities and neighbourhood obesity rates. Increasing distance to bariatric centres substantially influenced care delivery.

On the use of numerical modelling for near-field pollutant dispersion in urban environments--A review

This article deals with the state-of-the-art of experimental and numerical studies carried out regarding air pollutant dispersion in urban environments. Since the simulation of the dispersion field around buildings depends strongly on the correct simulation of the wind-flow structure, the studies performed during the past years on the wind-flow field around buildings are reviewed. This work also identifies errors that can produce poor results when numerically modelling wind flow and dispersion fields around buildings in urban environments. Finally, particular attention is paid to the practical guidelines developed by researchers to establish a common methodology for verification and validation of numerical simulations and/or to assist and support the users for a better implementation of the computational fluid dynamics (CFD) approach.

Synovitis with pitting edema as the presenting manifestation of systemic lupus erythematosus

Rheumatologists are increasingly aware of the entity synovitis with pitting edema. The remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome has been reported with an array of conditions that include polymyalgia rheumatica, rheumatoid arthritis, Sjögren’s syndrome and psoriatic arthropathy. Synovitis with pitting edema is now being increasingly recognized with systemic lupus erythematosus (SLE). We report a patient who presented with edema of hands and feet and was diagnosed eventually with definite SLE. With magnetic resonance imaging, joint effusions and tenosynovitis were confirmed to be associated with the otherwise-unexplained extremity edema.

High-titre circulating tissue transglutaminase-2 antibodies predict small bowel villous atrophy, but decision cut-off limits must be locally validated

Numerous studies suggest that high levels of circulating immunoglobulin (Ig)A tissue transglutaminase (TTG2) antibodies predict coeliac disease with high specificity. Accordingly, it has been suggested that duodenal biopsy may not be required routinely for diagnostic confirmation where quantitative serology identifies the presence of high antibody titres. However, defining a cut-off TTG2 threshold is problematic, as the multiple available assay methods are not harmonized and most studies have been focused on the paediatric population. Recent paediatric guidelines proposed a TTG2 antibody diagnostic cut-off at 10 × the upper limit of normal (ULN) for the method; however, concerns remain about errors of generalization, between both methods and laboratories. In this study, we used retrospective laboratory data to investigate the relationship between TTG2 antibody levels and Marsh 3 histology in the seropositive population of adults and children at a single centre. Among 202 seropositive patients with corresponding biopsies, it was possible to define a TTG2 antibody cut-off with 100% specificity for Marsh 3 histology, at just over 10 × ULN for the method. However, UK National External Quality Assurance Scheme returns during the study period showed a wide dispersion of results and poor consensus, both between methods and between laboratories using the same method. Our results support the view that high-titre TTG2 antibody levels have strong predictive value for villous atrophy in adults and children, but suggest that decision cut-offs to guide biopsy requirement will require local validation. TTG2 antibody assay harmonization is a priority, in order to meet the evolving requirements of laboratory users in this field.