Rapid detection of extended-spectrum β-Lactamases producers in Enterobacteriaceae using a calorimetry approach

AIM

To design and assess a novel protocol that employs isothermal titration calorimetry (ITC) for rapid detection of extended-spectrum β-lactamase (ESBL)-producers in clinical pathogens.

METHODS AND RESULTS

A total of 69 clinical Enterobacteriaceae isolates were examined in the new ESBL-ITC test by examining the heat profiles associated with enzyme hydrolysis of different substrates (imipenem, cefotaxime and clavulanic acid). The presence of β-lactamase genes in the bacteria tested was confirmed by PCR and DNA sequencing. Comparative analysis between ESBL-ITC and conventional minimum inhibitory concentrations (MIC)/combined disk method (CDM) showed high agreement between the two assays. However, the ESBL-ITC test had a remarkable advantage of providing testing result within 1 h, in comparison to the 32-48 h required by MIC/CDM.

CONCLUSIONS

The ESBL-ITC test developed in this work offers a new option for rapid and accurate detection of ESBL-producers.

SIGNIFICANCE AND IMPACT OF THE STUDY

Timely detection of ESBL-producers is vital to guide the decision-making process in clinical treatment as well as in hospital-infection control. The new ESBL-ITC test provides a rapid phenotypic assay that can be further adapted for clinical diagnosis of ESBL-producing pathogens.

Electron Microprobe/SIMS Determinations of Al in Olivine: Applications to Solar Wind, Pallasites and Trace Element Measurements

Electron probe microanalyzer measurements of trace elements with high accuracy are challenging. Accurate Al measurements in olivine are required to calibrate SIMS implant reference materials for measurement of Al in the solar wind. We adopt a combined EPMA/SIMS approach that is useful for producing SIMS reference materials as well as for EPMA at the ~100 μg g^-1 level. Even for mounts not polished with alumina photoelectron spectroscopy shows high levels of Al surface contamination. In order to minimize electron beam current density, a rastered 50 × 100 μm electron beam was adequate and minimized sensitivity to small Al-rich contaminants. Reproducible analyses of eleven SIMS-cleaned spots on San Carlos olivine agreed at 69.3 ± 1.0 μg g^-1• The known Al mass fraction was used to calibrate an Al implant into San Carlos. Accurate measurements of Al were made for olivines in the pallasites: lmilac, Eagle Station and Springwater. Our focus was on Al in olivine, but our technique could be refined to give accurate electron probe measurements for other contamination-sensitive trace elements. For solar wind, it is projected that the Al/Mg abundance ratio can be determined to 6%, a factor of 2 more precise than the solar spectroscopic ratio.

MFN2 contributes to metabolic disorders and inflammation in the aging of rat chondrocytes and osteoarthritis

OBJECTIVE

Metabolic disorders and inflammation of chondrocytes are major pathological changes in aging cells and osteoarthritis (OA). Recent studies demonstrated age-related mitochondrial dysfunction may be a key contributing factor in the development of OA. Mitofusin 2 (MFN2) is a key regulator of mitochondrial fusion, cell metabolism, autophagy and apoptosis. This study was performed to ascertain whether MFN2 was involved in the aging of chondrocytes and OA.

METHODS

Metabolic measurements were taken in rat chondrocytes between different ages (3-week, 5-month, 12-month). MFN2 activity was detected in both human and rat chondrocytes during aging and OA. Then, knockdown of MFN2 with small interfering RNA (siRNA) was performed to confirm whether MFN2 contributes to metabolic changes. Lentiviruses were used to establish MFN2-overexpression/knockdown OA models both in vivo and in vitro to confirm whether MFN2 contributes to OA progress. Further, regulatory mechanism of MFN2 was assessed and interaction between MFN2 and PARKIN was performed.

RESULTS

A metabolic shift to mitochondrial respiration was confirmed in rat chondrocytes during aging. MFN2 expression was elevated in both human and rat chondrocytes during aging and OA. Knockdown of MFN2 with siRNA reversed the age-related metabolic changes in rat chondrocytes. Overexpression of MFN2 exacerbated inflammation and OA progress, while knockdown of MFN2 ameliorated inflammation and OA progress. Further, MFN2 could be ubiquitinated by PARKIN, declined PARKIN expression during aging and OA might result in elevated MFN2 expression.

CONCLUSIONS

Elevated MFN2 contributes to metabolic changes and inflammation during aging of rat chondrocytes and osteoarthritis.

Dietary supplementation with Bacillus subtilis DSM 32315 alters the intestinal microbiota and metabolites in weaned piglets

AIM

The study was conducted to investigate the effects of dietary Bacillus subtilis (BS) DSM 32315 on the intestinal microbiota composition and metabolites of weaned pigs.

METHODS AND RESULTS

Sixty-four piglets were allocated to two groups (control and BS), each group including eight replicates with four piglets. Dietary BS DSM 32315 increased (P < 0·05) the abundances of jejunal Leucobacter and Cupriavidus, ileal Thermus, Coprococcus and Bifidobacterium, as well as colonic Succiniclasticum; and increased the concentrations of ileal straight-chain fatty acids, colonic propionate, branched-chain fatty acids (BCFAs), and tyramine, but decreased (P < .05) the colonic indole concentration. The ileal and colonic microbial community structure tended to cluster into two groups. LEfSe analysis identified five microbial biomarkers in jejunum and eight biomarkers in ileum in the BS group, and three biomarkers in colon in the control group. The ileal Bifidobacterium abundance was positively correlated (P < 0·05) with isovalerate concentration, while the colonic Actinobacteria and Lactobacillus abundances were negatively correlated (P < 0·05) with indole concentration.

CONCLUSION

These findings suggest that dietary supplementation with BS DSM 32315 could alter the diversity, composition, and metabolites of intestinal microbiota in weaned piglets.

SIGNIFICANCE AND IMPACT OF THE STUDY

Weaned piglets are often accompanied with impaired gastrointestinal tract and intestinal disorder affecting their growth. This study demonstrated that dietary BS DSM 32315 presented a beneficial role in gut health via regulating intestinal microbiota composition and metabolites.

ELECTROACUPUNCTURE IMPROVES INSULIN SENSITIVITY IN HIGH-FAT DIET-INDUCED INSULIN RESISTANT RATS BY ACTIVATING SIRT1 AND GLUT4 IN QUADRICEPS FEMORIS

OBJECTIVES

To assess the effects of electroacupuncture (EA) at the Zusanli (ST36), Guanyuan (CV4), Zhongwan (CV12), and Fenglong (ST40) acupoints on sirtuin 1 (SIRT1) and glucose transporter type 4 (GLUT4) expression in high-fat diet (HFD)-induced insulin-resistant (IR) rats.

METHODS

Wistar rats were divided into normal control (NC), HFD, and HFD+EA groups. NC rats were fed a standard chow diet and did not receive EA. After being fed an HFD for eight weeks, rats in the HFD+EA group received EA at 2 Hz five times a week for eight weeks. Rats in the HFD group did not receive EA.

RESULTS

In HFD-induced IR rats, EA inhibited body weight increase and water intake, which were observed in HFD rats. EA had no effect on fasting blood glucose and postprandial blood sugar levels. Intraperitoneal insulin tolerance testing revealed that EA enhanced insulin sensitivity in HFD-induced IR rats. Compared with NC rats, SIRT1 and GLUT4 were downregulated in the quadriceps femoris of HFD-fed rats but were increased after eight weeks of EA stimulation.

CONCLUSIONS

EA enhanced HFD-induced insulin resistance by activating SIRT1 and GLUT4 in the quadriceps femoris. These results provide powerful evidence supporting the beneficial effects of EA on HFD-induced insulin resistance.

SAT0447 CORRELATES OF RADIAL BONE MICROARCHITECTURES IN OLDER ADULTS

Background:

Weight, dietary patterns, vitamin D, physical activity and grip strength have been suggested to be associated with bone loss in older adults. However, studies have yet been performed to investigate the associations between these factors and radial bone microarchitecture.

Objectives:

This study aimed to describe the associations of weight, dietary patterns, serum 25-hydroxyvitamin D (25(OH)D) concentrations, physical activity and grip strength with bone measures in older adults.

Methods:

Cross-sectional data on 201 older adults (mean age 72 years, female 46%) from a population-based cohort study were analysed. Weight, dietary patterns, serum 25(OH)D concentrations, physical activity (steps per day), grip strength were collected and analysed from baseline to 10-year follow-up. Areal bone mineral density (aBMD) at spine, hip and whole body were measured by dual-energy X-ray absorptiometry (DXA). Radial cortical and trabecular bone microarchitectures were measured by high-resolution peripheral computed tomography (HRpQCT). Multivariable linear regression was used to analyse associations of study factors with bone measures.

Results:

Weight was positively associated with radial bone area (total: β=0.18, 95% CI: 0.07, 0.29; cortical: β=0.12, 95% CI: 0.03, 0.21; trabecular: β=0.18, 95% CI: 0.05, 0.32), and was inversely associated with compact cortical volumetric bone mineral density (vBMD) (β= -0.19, 95% CI: -0.37, -0.01) and trabecular thickness (β= -0.25, 95% CI: -0.43, -0.07). Ten-year changes in weight were not significantly associated with bone measures, apart from radial trabecular separation (β= 0.15, 95%CI: 0.009, 0.28). Western dietary pattern scores were inversely associated with radial vBMD (total: β= -0.17, 95% CI: -0.32, -0.01; cortical: β= -0.19, 95% CI: -0.34, -0.04; compact cortical: β= -0.19, 95% CI: -0.34, -0.04; outer transitional zone: β= -0.20, 95% CI: -0.35, -0.06), and were positively associated with cortical porosity (cortical: β= 0.18, 95% CI: 0.03, 0.33; compact cortical: β= 0.19, 95% CI: 0.04, 0.34; outer transitional zone: β= 0.20, 95% CI: 0.06, 0.35). Steps per day were not significantly associated with bone measures, apart from inner transitional zone area and thickness (β= 0.12, 95% CI: 0.003, 0.24; β= 0.19, 95% CI: 0.05, 0.33). Healthy food pattern scores, serum 25(OH)D and grip strength were not significantly associated with radial HRpQCT measures.

Conclusion:

Higher weight, but not weight change, was beneficial for radial cortical and trabecular bone area but also associated with worse compact cortical vBMD and trabecular thickness. Higher western dietary pattern scores had adverse effects on radial vBMD and cortical porosity while physical activity had inconsistent associations.

Disclosure of Interests:

None declared

0380 Association of Day-to-Day Variability in Rest-Activity Circadian Rhythm with Sleep Quality Among Law Enforcement Officers

Introduction

Poor sleep quality may be attributed to several occupational factors and has been linked to adverse health outcomes, including cardiovascular disease. Recent epidemiologic studies suggest rest-activity circadian rhythm (RAR) as a possible determinant of poor sleep quality. The focus of these studies has been on the magnitude of the parameters of RAR with little attention to the impact of their day-to-day fluctuation. We examined association of daily variation in parameters of RAR with sleep quality.

Methods

Participants (n=280) were officers from the Buffalo Cardio-metabolic Occupational Police Stress Study (2004-2009). Sleep quality was determined using the Pittsburgh Sleep Quality Index (PSQI). Participants wore wrist actigraph for a minimum of seven days. A cosine curve was fit to measure goodness of fit and estimate the mean values of the three parameters of RAR: Mesor, Amplitude, and Acrophase. Day-to-day variability of the parameters were assessed by fitting the cosine function separately for each day and computing the sample standard deviation across the days. Poisson regression models were conducted adjusting for demographic, lifestyle, and occupational factors.

Results

The prevalence of poor sleep quality was 50.3%. Poor sleep quality was 56% higher in officers with the largest day-to-day variability in Mesor (PR=1.56, 95%CI:1.11 - 2.19) compared to those with the lowest daily variation. Similar estimates were found for Amplitude (PR=1.42, 1.03 - 1.95), Acrophase (PR=1.86, 1.29 - 2.67), and measure of goodness of fit (PR=1.54, 1.13 - 2.11). On the other hand, mean values of RAR parameters were not significantly associated with poor sleep quality.

Conclusion

Results suggest larger daily variation in parameters of RAR is associated with a decrease in sleep quality. Given that day-to-day variation in RAR may increase the odds of poor sleep quality, future studies ought to address risk factors for higher daily fluctuations in RAR which could aid in developing intervention measures.

Support

CDC/NIOSH grant 1R01OH009640-01A1

0797 Restless Legs Syndrome and Perceived Olfactory and Taste Dysfunction: A Community-Based Study

Introduction

Restless legs syndrome (RLS), an under-recognized sensorimotor condition worldwide, is thought to be a prodromal symptom of Parkinson’s disease as suggested by previous evidences. However, its association with prodromal chemosensory impairments, including olfactory or taste dysfunction, has remained largely unknown. Few studies of small sample sizes were conducted in predominantly Caucasian populations and results were inconsistent.

Methods

We performed a cross-sectional analysis including 90,337 Chinese adults free of neurodegenerative diseases in the Kailuan study in 2016. Presence of RLS was defined using revised RLS diagnostic criteria and further verified by Cambridge-Hopkins questionnaire for RLS. Perceived olfactory and taste dysfunction was collected via a questionnaire. The association between RLS and perceived olfactory and taste dysfunction was assessed using logistic regression model, adjusting for potential cofounders such as age, sex, smoking, alcohol consumption sleep conditions and medical history.

Results

RLS was associated with high odds of having perceived olfactory and/or taste dysfunction (adjusted odds ratio =5.92; 95% confidence interval, 3.11, 11.3). The significant association persisted when using Cambridge-Hopkins questionnaire for RLS (adjusted odds ratio =5.55; 95% confidence interval, 2.37-13.0) or when excluding participants with major chronic diseases.

Conclusion

RLS was associated with increased odds of perceived olfactory and taste dysfunction.

Support

This research was supported by start-up grant from the College of Health and Human Development and the Department of Nutritional Sciences, Pennsylvania State University, the Institute for CyberScience Seed Grant Program, Pennsylvania State University, and Natural Science Foundation of Hebei Province (H2018209318).

[Guidelines for the use of post-traumatic tetanus vaccines and passive immune preparation]

Post-traumatic tetanus is the main type of non-neonatal tetanus. To reduce the incidence and mortality rateof tetanus and guide the primary medical institutions to prevent and control tetanus after trauma, the National Immunization Planning Technical Working Group of the Chinese Center for Disease Control and Prevention has compiled this document in the reference with Position Paper by World Health Organization, and the latest research progress both at home and abroad. The guidelines focus on the basic procedures for the prevention and treatment of post-traumatic tetanus, the application of tetanus vaccines and immune preparation, and pre-exposure immunization in high-risk populations of trauma.

MR Imaging Correlates for Molecular and Mutational Analyses in Children with Diffuse Intrinsic Pontine Glioma

BACKGROUND AND PURPOSE

Recent advances in molecular techniques have characterized distinct subtypes of diffuse intrinsic pontine gliomas. Our aim was the identification of MR imaging correlates of these subtypes.

MATERIALS AND METHODS

Initial MRIs from subjects with diffuse intrinsic pontine gliomas recruited for a prospective clinical trial before treatment were analyzed. Retrospective imaging analyses included FLAIR/T2 tumor volume, tumor volume enhancing, the presence of cyst and/or necrosis, median, mean, mode, skewness, kurtosis of ADC tumor volume based on FLAIR, and enhancement at baseline. Molecular subgroups based on EGFR and MGMT mutations were established. Histone mutations were also determined (H3F3A, HIST1H3B, HIST1H3C). Univariate Cox proportional hazards regression was used to test the association of imaging predictors with overall and progression-free survival. Wilcoxon rank sum, Kruskal-Wallis, and Fisher exact tests were used to compare imaging measures among groups.

RESULTS

Fifty patients had biopsy and MR imaging. The median age at trial registration was 6 years (range, 3.3-17.5 years); 52% were female. On the basis of immunohistochemical results, 48 patients were assigned to 1 of 4 subgroups: 28 in MGMT-/epidermal growth factor receptor (EGFR)-, 14 in MGMT-/EGFR+, 3 in MGMT+/EGFR-, and 3 in MGMT+/EGFR+. Twenty-three patients had histone mutations in H3F3A, 8 in HIST1H3B, and 3 in HIST1H3C. Enhancing tumor volume was near-significantly different across molecular subgroups (P = .04), after accounting for the false discovery rate. Tumor volume enhancing, median, mode, skewness, and kurtosis ADC T2-FLAIR/T2 were significantly different (P ≤ .048) between patients with H3F3A and HIST1H3B/C mutations.

CONCLUSIONS

MR imaging features including enhancement and ADC histogram parameters are correlated with molecular subgroups and mutations in children with diffuse intrinsic pontine gliomas.

Chinese expert group consensus on diagnosis and clinical management of osteoradionecrosis of the mandible

Osteoradionecrosis of the mandible (MORN) is one of the most devastating complications caused by radiation therapy in the head and neck region. It is characterized by infection and chronic necrosis of the mandible as the main manifestation. Clinically, MORN-related symptoms include swelling, pain, dysphagia, trismus, masticatory or speech disorders, refractory orocutaneous fistula, bone exposure, and even pathological fracture. MORN has become a challenging clinical problem for oral and maxillofacial surgeons to deal with, but thus far, this problem has not been solved due to the lack of widely accepted treatment algorithms or guidelines. Because of the nonexistence of standardized treatment criteria, most clinical treatment against MORN nowadays is largely based on controversial empirical understandings, while recommendations on post-therapeutic evaluations are scarce. Therefore, to further unify and standardize the diagnosis and treatment of MORN, to decrease the huge waste of medical resources, and ultimately, to improve the wellbeing of the patients, the Chinese Society of Oral and Maxillofacial Surgery (CSOMS) convened an expert panel specialized in MORN from 16 domestic medical colleges and affiliated hospitals to discuss the spectrum of diagnosis and and formulate treatment. In addition, consensus recommendations were also revised with a comprehensive literature review of the previous treatment experiences and research pearls. This 'expert consensus statement on diagnosis and clinical management of MORN' is for clinical reference.

A28 RELATIVE RATES OF ULCERATIVE COLITIS TO CROHN’S DISEASE: PARALLEL EPIDEMIOLOGIES IN NEWLY VS. HIGHLY INDUSTRIALIZED COUNTRIES

Background

Inflammatory bowel disease (IBD) first presents in a population as cases of ulcerative colitis (UC) followed by cases of Crohn’s disease (CD). Newly industrialized countries (NIC) show a prallel epidemiology of IBD to highly industrialized countries (HIC) in the previous century; one marker of this is the relative incidence/prevalence rates of UC to CD, which approximates 1 over time.

Aims

Provide evidence for the UC:CD ratio as a proxy for disease penatrance in a population.

Methods

Systematic review of MedLine and Embase for studies reporting incidence or prevalence of UC and CD. Log-linear regression (by region and NIC/HIC [2019 United Nations definitions]) was used to calculate average annual percent change (AAPC) and associated 95% confidence intervals (CI). Data were plotted on an online, interactive map to show trends (link provided).

Results

We extracted data from 218 studies compising population-level data from 69 countries. We found negative AAPCs as the prevalence ratio of UC:CD significantly decreased over time in East Asia, West Asia, North Europe, and South Europe; 6/12 global regions displayed significantly decreasing incidence ratios. No AAPC was found to be significantly increasing (Table 1). When examing HIC/NIC, we found a significant effect of NIC on the UC:CD prevalence ratio after 2000 (AAPC:−3.83;95%CI:−6.28,−1.31) while HIC regions remained stable (AAPC:2.14;95%CI:−1.40,5.82). Looking at all available data, both HICs and NICs show significantly decreasing UC:CD prevalence ratios (HIC:AAPC:−3.72;95% CI:−4.46,−2.97; NIC:AAPC:−2.62;95%CI:−4.13,−1.08).

Conclusions

In some HICs (eg. Canada), the UC:CD incidence ratio was &lt;1 in the earliest available data (1966), explaining the stable AAPC in North America (AAPC:−0.24;95%CI:−1.12,0.65). However, in NICs (eg. Southern Asia), the AAPC is rapidly decreasing (AAPC:−24.68;95%CI:−37.85,−8.71) as areas like Sri Lanka rapidly fall from an incidence ratio of 7.5 (2007) to 2.8 (2012), mimicking trends in IBD epidimeology of HICs in the previous century.

Funding Agencies

None

A234 CLINICAL, ENDOSCOPIC AND HISTOLOGICAL IMPROVEMENT IN COMMON VARIABLE IMMUNODEFICIENCY DISEASE ASSOCIATED ENTEROPATHY WITH VEDOLIZUMAB

Background

Common variable immune deficiency (CVID) can be associated with autoimmune manifestations including enteric inflammation and diarrhea. Systemic immunosuppression used in patients with inflammatory bowel disease (IBD) may be associated with increased risk of infection in CVID.

Aims

We report a patient with CVID associated intestinal enteropathy who underwent clinical, endoscopic and histological improvement after treatment with vedolizumab (IgG1 monoclonal antibody to α4β7 integrin), as well as a concurrent systematic review (SR) of the literature.

Methods

Case report and systematic literature review. We searched EMBASE, Medline, Cochrane CENTRAL, clinialtrials.gov, and the International Clinical Trials Registry Platform without language restriction using key words to identify patients with CVID associated enteropathy treated with vedolizumab. Clinical, endoscopic and histological outcomes were extracted and safety data.

Results

A 32-year-old male presented with weight loss, anemia and hypoalbuminemia on a background of chronic diarrhea and recurrent sinus infections. Serology and genetic testing was not consistent with celiac disease. Pan-endoscopy showed complete villous atrophy in the duodenum and biopsies showed and intraepithelial lymphocytosis (IEL) in the duodenum and terminal ileum. CT abdomen showed pan-enteritis with extensive mesenteric lymphadenopathy which were reactive on lymph node excision, as well as bronchiectasis. Pneumococcal vaccination challenge to assess humoral response confirmed CVID. After suboptimal response with steroids and mercaptopurine, treatment was initiated with vedolizumab 300mg IV at weeks 0, 2, and 6, then 8 weekly. This led to normalization of stool frequency, weight gain as well as endoscopic and histological resolution within 6 months of treatment. The SR yielded 101 studies of which 3 case series were identified reporting a total of 7 patients with CVID. In 5 cases there was clinical improvement, 4 reported endoscopic improvement and 3 patients had histologic improvement. No safety concerns associated with vedolizumab were reported.

Conclusions

Vedolizumab, a selective leucocyte inhibitor to the gut, was able to induce either clinical, endoscopic or histological improvement in 8 published cases in the worldwide literature. Prospective studies are needed to determine whether this treatment could be included in the therapeutic armamentarium for this orphan indication.

Funding Agencies

None

A51 UTILIZING MUCIN-DERIVED SUGARS CONFERS A FITNESS ADVANTAGE TO THE ENTERIC PATHOGEN CITROBACTER RODENTIUM THAT PROMOTES INTESTINAL COLONIZATION

Background

Citrobacter rodentium is an enteric murine pathogen used to model the human diarrheal pathogens. Following inoculation, C. rodentium colonizes the mouse cecum where it expands and ultimately spreads to the distal colon. During this process, C. rodentium has to compete with commensal microbes for available nutrients. Moreover, to spread throughout the gut, and infect the intestinal epithelium, C. rodentium has to cross through, and or dwell within the intestinal mucus layer which is composed of the heavily glycosylated protein Muc2. Muc-2 is glycosylated and coated by 5 distinct terminal sugar residues: galactose, N-acetylgalactosamine, N-acetylglucosamine, fucose, and sialic acid. Many commensal microbes have the ability to cleave and free these sugars from the Muc2 protein, releasing them for their own consumption, however pathogens appear to exploit this process. While studies have indicated that C. rodentium uses these terminal sugar residues as a nutritional source, their relative importance in the pathogenic strategy of C. rodentium (and other gut pathogens) remains unclear

Aims

Investigate the role played by mucin sugar residues in controlling C. rodentium pathogenesis

Methods

Deletions of agaW, nagE, mglB, galP, fucK, and nanT were generated on the chromosome of C. rodentium (Strepr) by overlap extension PCR. Growth assays were performed to examine the growth kinetics of mutants C. rodentium in minimal (M9) media supplemented with one of the 5 mucin sugars or M9 with whole mucin as control. Specific pathogen free (SPF) C57BL/6 mice, or germfree C57BL/6 mice were orally gavaged with wildtype C. rodentium (Strepr) or one of ΔagaW, ΔnagE, ΔmglB, ΔgalP, ΔfucK, or ΔnanT strains. Mice were euthanized at 6 days post-infection, and the cecum, colon, and spleen were collected and histologically scored for pathology and intestinal and systemic bacterial burden. Stool samples were collected throughout the 6 days to quantify C. rodentium burdens

Results

Growth assays confirmed that the specific sugar transporter/kinase mutant C. rodentium strains grew normally when placed in media supplemented with whole mucin, or with most sugars, only showing overt defects in growth when solely supplemented with the sugar for which they were impaired. Several of the C. rodentium mutants including ΔnanT showed overt defects in colonization/infection of SPF C57BL/6 mice, but their pathogenesis was normalized in germfree mice, or in mice treated with the antibiotic streptomycin at each day post-infection. These findings indicate that the impact of mucin sugar utilization on C. rodentium virulence is microbiota-dependent

Conclusions

C. rodentium uses mucin sugars as nutrient source in the mouse gut, and an inability to use these sugars impairs their ability to infect their hosts in a microbiota dependent manner

Funding Agencies

CAG, CCC, CIHR, NRC

A215 PATIENTS WITH INFLAMMATORY BOWEL DISEASE ARE FREQUENTLY PRESCRIBED OPIOID ANALGESICS WHEN DISCHARGED FROM THE EMERGENCY DEPARTMENT

Background

Patients with inflammatory bowel disease (IBD) suffer a substantial burden of morbidity related to chronic abdominal pain and are susceptible to opioid dependence and abuse that is associated with increased rates of depression, hospitalization, and mortality. While opioid prescription and renewal by a single provider minimizes the long-term risk of misuse, many patients with IBD will seek out care in the emergency department (ED) where short-term, ‘to-go’ use of narcotic analgesia is associated with potential treatment-related complications.

Aims

To assess rates of opioid prescription in IBD patients presenting to the ED and to assess factors associated with opioid use.

Methods

This is a retrospective analysis of cross-sectional data collected in the United States National Hospital Ambulatory Medical Care Survey (NHAMCS) from 2006–2015. We compared a study population of adult IBD patients (International Classification of Diseases ICD-9 555.X, 556.X) ≥18 years discharged from the ED to a control group of patients presenting with non-specific abdominal pain (ICD-9 789.0, 564.1, 536.8). The proportion of patients given opioids in ED and at ED discharge were calculated with relative standard error (RSE), and national level estimates were produced using survey weights. Univariable and multivariable logistic regression was used to evaluate predictors of opioid prescription at discharge, expressed as odds ratios (OR) with 95% confidence intervals (CI).

Results

A total of 767,577 IBD patients were compared to 71,359,257 patients with non-specific abdominal pain. A total of 37.3% (RSE 4.7%) of IBD patients compared to 24.7% (RSE 0.8%) of controls (p&lt;0.01) received an opioid prescription on ED discharge. 49.1% (RSE 5.6%) of IBD patients compared to 37.2% (RSE 0.8%) of patients with non-specific abdominal pain (p=0.02) received an opioid while in ED. Significant predictors of narcotic prescription at discharge in multivariable analysis included: age &lt;50 (OR 6.83 [95% CI: 1.21, 38.48], p=0.03), non-white race (OR 4.73 [95% CI: 1.46, 15.39], p=0.01), and narcotic use in the ED (OR 5.27 [95% CI: 1.96, 14.21], p&lt;0.01).

Conclusions

Nearly 40% of IBD patients were prescribed an opioid at discharge from the ED. This rate is significantly higher than for patients who present with non-specific abdominal pain and younger, non-white IBD patients were disproportionately more likely to receive an opioid prescription. Given the risks associated with on-demand narcotic use in IBD patients, our data highlight a potential gap in care for accessing comprehensive pain management solutions.

Funding Agencies

None

A44 NOVEL AND HIGHLY SENSITIVE FLOW CYTOMETRIC BASED METHOD FOR CONTINUOUS TRACKING OF INTESTINAL PERMEABILTIY

Background

Inflammatory bowel diseases (IBD) are chronic, inflammatory conditions of the intestinal tract. In addition to a complex mixture of genetic, and environmental factors, increased intestinal permeability is also thought to be involved. Despite its diagnostic importance, there is no reliable yet minimally invasive way to measure intestinal permeability in patients and animal models. Currently, most assays involve the detection of orally given sugar molecules in either the urine (MLR method) or the plasma (FITC-dextran). These methods offer only limited accuracy, and do not allow continual tracking of intestinal permeability within the same animal due to the requirement of euthanization. Herein, we describe a novel cytometric-based method using an ingested dietary protein (ovalbumin (OVA)) and flow cytometry. We show our method is reliable, highly sensitive, minimally invasive and allows for the continuous tracking of intestinal permeability within the same individual using small blood volumes.

Aims

To compare the utility of our bead-based method of intestinal permeability measurement to the FITC-Dextran method.

Methods

Wildtype (WT) C57BL/6 mice, and mucin 2-deficient (Muc2-/-) mice (known to suffer a leaky gut) at baseline, or mice given chemical or infection-induced colitis were gavaged with a solution containing OVA protein and FITC-Dextran. After 6 hours, mice were euthanized to collect plasma for spectrophotometry (FITC-Dextran), or for flow cytometry (bead-based ELISA) analyses.

Results

We found that both OVA and FITC-dextran were detectable in plasma samples of the Muc2-/- mice, but not the WT mice, 6 hours after oral co-administration, however the bead-based method produced more consistent readings. Immunostaining of tissue sections with the same antibodies also showed that OVA can readily diffuse through the gut epithelium of Muc2-/- mice but not the WT mice, validating the specificity of the antibodies. We also tested our assay on WT mice undergoing dextran sodium sulfate (DSS) colitis, or infected with Citrobacter rodentium. We found that our method could detect statically significant changes in intestinal permeability 2 to 3 days earlier than the FITC-dextran method, while providing greatly reduced variability between technical repeats. More importantly, we were able to use a small volume (5 μL) of whole blood collected via tail poke, to measure intestinal permeability without requiring euthanization of the mice. This allowed the continuous tracking of permeability changes within the same animal.

Conclusions

We conclude that the bead-based method is more sensitive and reliable than the FITC-Dextran method as tested in several murine colitis models. More importantly, we showed that the bead-based method allows continual tracking of intestinal permeability within the same animal, enabling time course measurements.

Funding Agencies

CAG, CCC, CIHR, NRCBC Children’s Research Institute

[Clinical application effects of portable visual retractor in superficial temporal fascia flap harvesting]

Objective: To explore the clinical application effects of portable visual retractor in superficial temporal fascia flap harvesting. Methods: From January 2010 to June 2019, 27 patients meeting the inclusion criteria and planning to perform operation of superficial temporal fascia flap harvesting were admitted to the Department of Plastic and Reconstructive Surgery of the First Clinical Medical Center of the People's Liberation Army General Hospital. The patients were divided into traditional surgical method group [6 males and 3 females, aged (34±14) years], cold light source retractor group [6 males and 4 females, aged (35±16) years], and portable visual retractor group [7 males and 1 female, aged (30±14) years] according to way of superficial temporal fascia flap harvesting. The superficial temporal fascia flaps of patients in traditional surgical method group were resected by traditional way of resection, and the superficial temporal fascia flaps of patients in cold light source retractor group and portable visual retractor group were resected at assistance of cold light source retractor and portable visual retractor, respectively. Length of incision, operation time, intraoperative blood loss volume, postoperative drainage volume, and postoperative complication of patients in 3 groups were observed and recorded. Data were processed with Fisher's exact probability test, one-way analysis of variance, least significant difference test, Kruskal-Wallis H test, and Bonferroni correction. Results: The length of incision of patients in visual retractor group was (3.6±0.8) cm, significantly shorter than (12.6±1.6) cm in traditional surgical method group and (5.8±0.9) cm in cold light source retractor group (P<0.05). The incision length of patients in traditional surgical method group was significantly longer than that in cold light source retractor group (P<0.05). The operation time of patients in visual retractor group was 24.0 (23.3, 25.8) min, significantly shorter than 35.0 (30.5, 36.5) min in traditional surgical method group and 28.5 (26.8, 30.5) min in cold light source retractor group (H=16.5, 9.8, P<0.05). The operation time of patients in traditional surgical method group was significantly longer than that in cold light source retractor group (H=6.6, P<0.05). The intraoperative blood loss volume was (26±3) mL of patients in visual retractor group, significantly less than (34±4) mL in traditional surgical method group and (30±6) mL in cold light source retractor group (P<0.05). The intraoperative blood loss volume of patients in traditional surgical method group was significantly more than that in cold light source retractor group (P<0.05). The postoperative drainage volumes of patients in visual retractor group, cold light source retractor group, and traditional surgical method group were (33±4), (34±6), and (31±7) mL, respectively, and there were no significantly statistical differences in postoperative drainage volumes among patients in the three groups (F=0.3, P>0.05). There were no severe complications such as ischemia and necrosis of superficial temporal fascia flaps in patients of the three groups. One patient in cold light source retractor group had subcutaneous hematoma after operation, which was improved by removing stitches and hematoma. Conclusions: Superficial temporal fascia flap harvesting at the assistance of portable visual retractor has the advantages of clear visual field, simple operation, short operation time, small incision, and less intraoperative blood loss.

Effect of 6% hydroxyethyl starch 130/0.4 on kidney and haemostatic function in cardiac surgical patients: a randomised controlled trial

Whether third‐generation hydroxyethyl starch solutions provoke kidney injury or haemostatic abnormalities in patients having cardiac surgery remains unclear. We tested the hypotheses that intra‐operative administration of a third‐generation starch does not worsen postoperative kidney function or haemostasis in cardiac surgical patients compared with human albumin 5%. This triple‐blind, non‐inferiority, clinical trial randomly allocated patients aged 40–85 who underwent elective aortic valve replacement, with or without coronary artery bypass grafting, to plasma volume replacement with 6% starch 130/0.4 vs. 5% human albumin. Our primary outcome was postoperative urinary neutrophil gelatinase‐associated lipocalin concentrations, a sensitive and early marker of postoperative kidney injury. Secondarily, we evaluated urinary interleukin‐18; acute kidney injury using creatinine RIFLE criteria, coagulation measures, platelet count and function. Non‐inferiority (delta 15%) was assessed with correction for multiple comparisons. We enrolled 141 patients (69 starch, 72 albumin) as planned. Results of the primary analysis demonstrated that postoperative urine neutrophil gelatinase‐associated lipocalin (median (IQR [range])) was slightly lower with hydroxyethyl starch (5 (1–68 [0–996]) ng.ml⁻¹) vs. albumin (5 (2–74 [0–1604]) ng.ml⁻¹), although not non‐inferior [ratio of geometric means (95%CI) 0.91 (0.57, 1.44); p = 0.15] due to higher than expected variability. Urine interleukin‐18 concentrations were reduced, but interleukin‐18 and kidney injury were again not non‐inferior. Of 11 individual coagulation measures, platelet count and function, nine were non‐inferior to albumin. Two remaining measures, thromboelastographic R value and arachidonic acid‐induced platelet aggregation, were clinically similar but with wide confidence intervals. Starch administration during cardiac surgery produced similar observed effects on postoperative kidney function, coagulation, platelet count and platelet function compared with albumin, though greater than expected variability and wide confidence intervals precluded the conclusion of non‐inferiority. Long‐term mortality and kidney function appeared similar between starch and albumin.

[Guidelines for the use of post-traumatic tetanus vaccines and passive immune preparation]

Post-traumatic tetanus is the main type of non-neonatal tetanus. To reduce the incidence and mortality rate of tetanus and guide the primary medical institutions to prevent and control tetanus after trauma, National Immunization Planning Technical Working Group of the Chinese Center for Disease Control and Prevention has compiled this document in the reference with Position Paper by World Health Organization, the latest research progress from home and abroad. The guidelines focus on the basic procedures for the prevention and disposition of post-traumatic tetanus, the application of tetanus vaccines and immune preparation, and the pre-exposure immunization in high-risk populations of trauma.

[Vaccine loss related to the expanded immunization program in Xinjiang Uygur Autonomous Region, 2016-2017]

Objective: To assess the vaccine loss related to the Expanded Program on Immunization (EPI) in Xinjiang Uygur Autonomous Region so as to improve the management of vaccines. Methods: A total of 135 vaccination clinics were randomly selected, using a stratified cluster sampling method. In each clinic, data on vaccination was collected between 2016 and 2017, including the number of doses in routine immunization program and supplementary immunization activities (i.e., vaccine doses in vials that were opened for use) on polio vaccine, number of doses administered to children and the number of doses discarded (e.g., expired vaccine or broken vials that had not been opened for use), etc. Coefficient on vaccine loss was calculated with the following equation: vaccine loss coefficient=(number of vaccine doses used)/(number of vaccine doses administered). The vaccine discard rate appeared as: number of vaccine doses discarded)/number of vaccine doses used. Results: For vaccines in single-dose vials [diphtheria-tetanus-pertussis vaccine (DTaP) and trivalent oral polio virus vaccine (tOPV)], the loss coefficients appeared as 1.00 and 1.02, respectively. For vaccines in multi-dose vials [bivalent oral polio vaccine (bOPV), group A meningococcal polysaccharide vaccine (MPV-A), diphtheria-tetanus combined vaccine (DT) and bacilli Calmette-Guérin (BCG) vaccine], the loss coefficients were 1.58, 1.67, 1.68, and 3.02, respectively. The coefficients of EPI vaccine loss in urban, rural, and pastoral area vaccination clinics ranged between 1.00-2.84, 1.00-3.71, and 1.00-2.27, respectively. Loss coefficients ranged between 1.00-3.00, 1.00- 4.41, and 1.00-1.94, respectively, were seen in township clinics, village clinics, and decentralized vaccination clinics. Coefficients on larger vaccine loss were associated with longer intervals between clinic sessions and with fewer vaccinations administrations per day. Conclusions: In Xinjiang, coefficients on the loss of multi-dose EPI vaccines were high. The coefficients on loss were different from the levels of region and types of clinics, and time interval between clinic sessions. Programs on refining the management and distribution of EPI vaccines, to minimize the vaccine loss were recommended.