Emergence of cfr-Mediated Linezolid Resistance in Staphylococcus aureus Isolated from Pig Carcasses

Altogether, 2547 Staphylococcus aureus isolated from cattle (n = 382), pig (n = 1077), and chicken carcasses (n = 1088) during 2010-2017 were investigated for linezolid resistance and were further characterized using molecular methods. We identified linezolid resistance in only 2.3% of pig carcass isolates. The linezolid-resistant (LR) isolates presented resistance to multiple antimicrobials, including chloramphenicol, clindamycin, and tiamulin. Molecular investigation exhibited no mutations in the 23S ribosomal RNA. Nevertheless, we found mutations in ribosomal proteins rplC (G121A) and rplD (C353T) in one and seven LR strains, respectively. All the LR isolates carried the multi-resistance gene cfr, and six of them co-carried the mecA gene. Additionally, all the LR isolates co-carried the phenicol exporter gene, fexA, and presented a high level of chloramphenicol resistance. LR S. aureus isolates represented 10 genotypes, including major genotypes ST433-t318, ST541-t034, ST5-t002, and ST9-t337. Staphylococcal enterotoxin and leukotoxin-encoding genes, alone or in combination, were detected in 68% of LR isolates. Isolates from different farms presented identical or different pulsed-field gel electrophoresis patterns. Collectively, toxigenic and LR S. aureus strains pose a crisis for public health. This study is the first to describe the mechanism of linezolid resistance in S. aureus isolated from food animal products in Korea.

First Report of an Escherichia coli Strain Carrying the Colistin Resistance Determinant mcr-1 from a Dog in South Korea

We studied the presence of the mobile colistin resistance gene mcr-1 in Escherichia coli isolates recovered from fecal and urine samples of companion animals, that were collected from South Korea in 2018 and 2019. The mcr-1 gene was detected in one colistin-resistant E. coli isolated from a diarrheic dog. The isolate exhibited additional resistance to multiple antimicrobials, including fluoroquinolones and third-generation cephalosporins. The mcr-1 carrying isolate belonged to ST160. The pulsed-field gel electrophoresis pattern of our strain differed from those ST160 E. coli strains previously identified from chickens in Korea. The mcr-1 gene was identified in the IncI2 plasmid. It was also transferred to E. coli J53 recipient strain, with a conjugation efficiency of 2.8 × 10-4. Average nucleotide identity analysis demonstrated that the mcr-1-carrying plasmid in this study was closely related to those from patients in Korea. To the best of our knowledge, this is the first report of mcr-1 carrying E. coli from a companion animal in South Korea. Our findings support One Health approach is necessary to prevent the dissemination of this high-risk gene.

Resistance Profiling and Molecular Characterization of Extended-Spectrum/Plasmid-Mediated AmpC β-Lactamase-Producing Escherichia coli Isolated from Healthy Broiler Chickens in South Korea

We aimed to identify and characterize extended-spectrum β-lactamase (ESBL)-and/or plasmid-mediated AmpC β-lactamase (pAmpC)-producing Escherichia coli isolated from healthy broiler chickens slaughtered for human consumption in Korea. A total of 332 E. coli isolates were identified from 339 cloacal swabs in 2019. More than 90% of the isolates were resistant to multiple antimicrobials. ESBL/pAmpC-production was noted in 14% (46/332) of the isolates. Six of the CTX-M-β-lactamase-producing isolates were found to co-harbor at least one plasmid-mediated quinolone resistance gene. We observed the co-existence of blaCMY-2 and mcr-1 genes in the same isolate for the first time in Korea. Phylogenetic analysis demonstrated that the majority of blaCMY-2-carrying isolates belonged to subgroup D. Conjugation confirmed the transferability of blaCTX-M and blaCMY-2 genes, as well as non-β-lactam resistance traits from 60.9% (28/46) of the ESBL/pAmpC-producing isolates to a recipient E. coli J53. The ISECP, IS903, and orf477 elements were detected in the upstream or downstream regions. The blaCTX-M and blaCMY-2 genes mainly belonged to the IncI1, IncHI2, and/or IncFII plasmids. Additionally, the majority of ESBL/pAmpC-producing isolates exhibited heterogeneous PFGE profiles. This study showed that healthy chickens act as reservoirs of ESBL/pAmpC-producing E. coli that can potentially be transmitted to humans.

Transverse Single-Spin Asymmetry for Very Forward Neutral Pion Production in Polarized p+p Collisions at sqrt[s]=510 GeV

Transverse single-spin asymmetries of very forward neutral pions generated in polarized p+p collisions allow us to understand the production mechanism in terms of perturbative and nonperturbative strong interactions. During 2017, the RHICf Collaboration installed an electromagnetic calorimeter in the zero-degree region of the STAR detector at the Relativistic Heavy Ion Collider (RHIC) and measured neutral pions produced at pseudorapidity larger than 6 in polarized p+p collisions at sqrt[s]=510  GeV. The large nonzero asymmetries increasing both in longitudinal momentum fraction x_{F} and transverse momentum p_{T} have been observed at low transverse momentum p_{T}<1  GeV/c for the first time, at this collision energy. The asymmetries show an approximate x_{F} scaling in the p_{T} region where nonperturbative processes are expected to dominate. A non-negligible contribution from soft processes may be necessary to explain the nonzero neutral pion asymmetries.

Predictors of permanent stoma creation in patients with mid or low rectal cancer: results of a multicentre cohort study with preoperative evaluation of anal function

AIM

Preoperative factors predictive of permanent stoma creation were investigated in a long-term follow-up of patients with mid or low rectal cancer.

METHOD

We included patients who underwent radical resection for mid or low rectal cancer with available data for preoperative anal function measured by manometry and Faecal Incontinence Severity Index questionnaire between January 2005 and December 2015 in three tertiary referral hospitals. A permanent stoma was defined as a stoma present until the patient's last follow-up visit or death. Preoperative factors that predicted permanent stoma creation were analysed.

RESULTS

Over a median follow-up of 57.4 months (range 12-143 months), a permanent stoma was created in 144/577 (25.0%) patients, including 89 (15.4%) who underwent abdominoperineal resection, one (0.2%) who underwent Hartmann's operation without reversal, 15 (2.6%) with a diverting ileostomy at the time of initial sphincter-preserving surgery without undergoing stoma reversal, and 39 (6.8%) who underwent permanent ileostomy formation after sphincter-preserving surgery. Patients with permanent stoma creation had a shorter tumour distance from the anal verge (P < 0.001), larger tumour size (P = 0.020) and higher preoperative Faecal Incontinence Severity Index score (P = 0.020). On multivariable analysis, tumour distance from the anal verge predicted permanent stoma formation (relative risk 0.53 per centimetre increase; 95% confidence interval 0.46-0.60; P < 0.001) but preoperative anal function did not.

CONCLUSION

Tumour distance from the anal verge was the only preoperative determinant of permanent stoma creation in rectal cancer patients. These data may help mid and low rectal cancer patients understand the need for permanent stoma.

In vivo neutron capture therapy of cancer using ultrasmall gadolinium oxide nanoparticles with cancer-targeting ability

Gadolinium neutron capture therapy (GdNCT) is considered as a new promising cancer therapeutic technique. Nevertheless, limited GdNCT applications have been reported so far. In this study, surface-modified ultrasmall gadolinium oxide nanoparticles (UGNPs) with cancer-targeting ability (d_avg = 1.8 nm) were for the first time applied to the in vivo GdNCT of cancer using nude model mice with cancer, primarily because each nanoparticle can deliver hundreds of Gd to the cancer site. For applications, the UGNPs were grafted with polyacrylic acid (PAA) for biocompatibility and colloidal stability, which was then conjugated with cancer-targeting arginylglycylaspartic acid (RGD) (shortly, RGD-PAA-UGNPs). The solution sample was intravenously administered into the tails of nude model mice with cancer. At the time of the maximum accumulation of the RGD-PAA-UGNPs at the cancer site, which was monitored using magnetic resonance imaging, the thermal neutron beam was locally irradiated onto the cancer site and the cancer growth was monitored for 25 days. The cancer growth suppression was observed due to the GdNCT effects of the RGD-PAA-UGNPs, indicating that the surface-modified UGNPs with cancer-targeting ability are potential materials applicable to the in vivo GdNCT of cancer.

A cancer growth suppression was observed due to the GdNCT effects of the RGD-PAA-UGNPs.

53 The Development and Education of Fall Prevention Program Through the Multidisciplinary Approach

Introduction

To reduce the rate of falls in the rehabilitation ward, fall prevention program was developed and educated for physical and occupational therapists, which increased the attitude towards falls and knowledge towards fall prevention activities.

Method

Participants of this study include 17 therapists currently employed at a university-affiliated hospital located in Gyeongg-do, South Korea. Systematic protocol for fall prevention with the emphasis in the roles of rehabilitation teams was developed. This standardized protocol consists of educating therapists with adequate assistive device use, safe ambulation techniques, and client-centered transfer techniques. The therapists then record the paitent's status related to fall prevention and or risks, which is then shared with other medical professionals including registered nurses and medical doctors. Paper-based questionnaires regarding 9 questions on attitude towards falls and 12 questions on knowledge towards fall prevention activities were done by the participants after the education of systematic protocol. The rate of falls was then compared with the change of attitudes in participants. Rate of falls was calculated by dividing the number of fall by the patient bed days and multiplying by 1000.

Result

After the education of fall prevention program, the mean score of attitude towards falls significantly increased (t=-3.99, p=0.001). The mean score of knowledge towards fall prevention activities significantly increased (t=-4.79, p&lt;0.001). The rate of falls decreased from 4.2 to 1.4. The effectiveness of systematic protocol regarding therapists' change in attitude and the resulting change in rate of falls was mainly seen in patients' ward. The decline in rate of falls was observed when patients transferred from bed to wheelchair.

Conclusion

In order to effectively convey the fall prevention education program, the multidisciplinary approach showed promising results in this study. Implications for future research include translation of this program to the community, such as long term care facility.

Characterization Of Chromosome-Mediated Colistin Resistance In Escherichia coli Isolates From Livestock In Korea

Purpose

Colistin resistance in gram-negative bacteria from humans and livestock has been increasingly reported worldwide. The aim of this study was to investigate the underlying mechanisms of chromosome-mediated colistin resistance in Escherichia coli isolates from livestock in Korea.

Materials and methods

Thirty mcr-1-negative isolates were selected from a collection of colistin-resistant E. coli isolates collected from livestock in 2005 and 2015 in Korea. Amino acid alterations in PmrAB, PhoPQ, MgrB, and PmrD were investigated. Colistin-resistant derivatives were produced by serial passage of colistin-susceptible E. coli isolates in colistin-containing media.

Results

Thirty colistin-resistant mcr-negative E. coli isolates were classified into 26 sequence types. Twenty-two isolates carried diverse amino acid alterations in PmrB, PhoP, PhoQ, MgrB, and/or PmrD, whereas no mutation in any of these genes was found in the remaining eight isolates. Sixteen out of the 22 isolates shared a total of nine polymorphic positions that were found in colistin-susceptible E. coli strains. Colistin-resistant derivatives from two colistin-susceptible isolates showed the same genetic alterations that were observed in colistin-resistant clinical isolates.

Conclusion

Our results suggest that the mechanism underlying chromosome-mediated colistin resistance remain to be discovered in E. coli. Selective pressure of colistin in vitro induced the same genetic mutations associated with colistin resistance in vivo. Efforts to reduce colistin consumption in livestock should be redoubled, to prevent the occurrence of colistin-resistant E. coli strains.

P4791Performance of the HAS-BLED, ATRIA, and PRECISE-DAPT Bleeding Risk Scores in Atrial Fibrillation Patients Using Antiplatelet Agents or Oral Anticoagulants

Background

Various bleeding risk scores have been proposed to assess the risk of bleeding in atrial fibrillation (AF) patients undergoing anticoagulation. PRECISE DAPT score has been developed to assess the out-of hospital bleeding risk in patients receiving dual antiplatelet therapy (DAPT). Our objective was to compare the predictive performance between the HAS-BLED (Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile International Normalized Ratio, Elderly, Drugs/Alcohol), ATRIA (Anticoagulation and Risk Factors in Atrial Fibrillation), and PRECISE-DAPT (Predicting Bleeding Complication in Patients Undergoing Stent Implantation and Subsequent Dual Antiplatelet therapy) score in AF patients using antiplatelet agents or anticoagulants

Methods

We recruited 1,114 consecutive AF patients (51% male; median age, 71 years) receiving antiplatelet agents or oral anticoagulants from January 2014 through December 2018. Major bleeding was defined as according to the Bleeding Academic Research Consortium (BARC) criteria (type 3 or 5: hemodynamic instability, need for transfusion, drop in hemoglobin ≥3 g, and intracranial, intraocular or fatal bleeding). The performance of risk scores were assessed by C-statistic.

Results

Bleeding events occurred in 135 patients (12.1%) during 30 days, and 72 patients (6.5%) from 30 days till 1-year follow-up. Based on the C-statistic, PRECISE-DAPT score (AUC: 0.72, 95% CI: 0.69–0.75) had a good performance, significantly better than HAS-BLED (AUC: 0.64, 95% CI: 0.61–0.67) (p=0.008) or ATRIA scores (AUC: 0.57, 95% CI: 0.54–0.60) (p<0.001) for 30-days bleeding prediction. Also, PRECISE-DAPT score had a good C-statistic (AUC: 0.72, 95% CI: 0.69–0.75) for 1-year bleeding events compared with HAS-BLED (AUC: 0.64, 95% CI: 0.60–0.67) (p=0.02) or ATRIA (AUC: 0.61, 95% CI: 0.58–0.65) (p=0.01).

ROC curve for bleeding

Conclusions

The PRECISE-DAPT score has been used for assessing bleeding events during DAPT. Also, the PRECISE-DAPT score predicted bleedings better than HAS-BLED or ATRIA scores in AF patients. So, the PRECISE-DAPT score may be considered as bleeding risk score during DAPT or oral anticoagulation in clinical practice.

P4776Age-dependent anti-thrombotic therapy for atrial fibrillation patients with intermediate risk (CHA2DS2-VASc Score of 1 or 2) of ischemic stroke

Background

Although older age is one of the most important risk factor for stroke in atrial fibrillation (AF), it is unclear whether oral anticoagulants are beneficial for AF patients with intermediate CHA2DS2-VASc score (1 for male or 2 for female) according to age threshold. We sought to investigate the effect of age-dependent antithrombotic therapy for ischemic stroke in Korean intermediate risk AF patients.

Methods

We enrolled 29,592 patients (males with CHA2DS2-VASc score of 1 and females with CHA2DS2-VASc score of 2) using the Korean National Health Insurance Service database. The clinical endpoint was the occurrence of ischemic stroke. The propensity score matching method was used to balance covariates across treated and untreated patients.

Results

Treated male AF patients were 6,570 (67.1%) with age <55 years, 7,115 (70.9%) with 55–64 years and 6,470 (68.3%) with 65–74 years in each age risk criterion. Also, treated female AF patients were 3,156 (71.3%) with age <55 years, 2,838 (71.0%) with 55–64 years and 3,440 (72.6%) with 65–74 years in each age risk criterion. Among male and female patients (age <55 years and 55–64 years) with 1 risk factor, an annual ischemic stroke rate was not significantly different between treated and untreated patients at full follow-up. However, treated AF patients who are in age 65–74 year without other risk factor had a much lower annual risk of ischemic stroke [(1.05%/year (male) and 1.04%/year (female)] compared with untreated patients [(1.77%/year (male) (p<0.026) and 1.86%/year (female) (p<0.041).

Conclusions

Age is an important predictor in determining the risk of ischemic stroke in AF patients with intermediate CHA2DS2-VASc scores (1 for male or 2 for female). We suggest that the benefit of anti-thrombotic therapy for intermediate risk AF patients depends on age threshold.

P5661Validation of CHA2DS2-VA score (excluding female sex) in non-valvular atrial fibrillation patients: a nationwide population-based study

Background

Sex category (Sc, ie, female sex) confers 1 point on CHA2DS2-VASc score. So, no woman with atrial fibrillation (AF) can have a CHA2DS2-VASc score of 0. This study aimed to compare CHA2DS2-VA (excluding female sex) and CHA2DS2-VASc score in Korean AF patients.

Methods

Using the Korean National Health Insurance Service database, we analyzed the risk of ischemic stroke in non-valvular AF patients between 2013 and 2017. The predictive value of the CHA2DS2-VA and CHA2DS2-VASc scores for ischemic stroke was evaluated by c-statistic difference and net reclassification improvement (NRI). The propensity score matching method was used to balance covariates across male and female AF patients.

Results

A total of 182,133 patients with AF (49.2% women) were included to this study. The adjusted incidence rate (IR) of ischemic stroke was not significantly different between males and females (0.89%/y and 0.90%/y, respectively, p=0.411) in low-risk patients without risk factor. Also, no sex difference was found in high-risk patients with above 2 risk factors for ischemic stroke (4.46%/y for male and 4.49%/y for male, p=0.498). In c-statistic analysis for ischemic stroke, there was no significant difference between the CHA2DS2-VA and CHA2DS2-VASc scores (AUC 0.662 vs. 0.664, z=1.572, p=0.116). When compared with CHA2DS2-VASc score, CHA2DS2-VA score was not significantly inferior in net reclassification improvement (NRI 0.031, 95% CI 0.002–0.037, p=0.118) for ischemic stroke.

C-statistics

Conclusions

In Korean AF patients, the CHA2DS2-VA score excluding female sex is a useful risk scoring system for ischemic stroke.

The impact of social media on citation rates in coloproctology

AIM

This study aimed to investigate the association between Twitter exposure and the number of citations for coloproctology articles.

METHOD

Original articles from journals using Twitter between June 2015 and May 2016 were evaluated for the following characteristics: publishing journal; article subject; study design; nationality, speciality and affiliation of the author(s); and reference on Twitter. Citation data for these articles were retrieved from Google Scholar (https://scholar.google.com) in January 2018. We performed a univariate analysis using these data followed by a multivariate, logistic regression analysis to search for factors associated with a high citation level, which was defined as accrual of more than five citations.

RESULTS

Out of six coloproctology journals listed on the InCites JCR database, three (Diseases of the Colon & Rectum, Colorectal Disease and Techniques in Coloproctology) used Twitter, where 200 (49.5%) out of a total of 404 articles had been featured. Citation rates of articles that featured on Twitter were significantly higher than those that did not (11.4 ± 9.2 vs 4.1 ± 3.1, P < 0.001). In multivariate analysis, Twitter exposure (OR 8.6, P = 0.001), European Union nationality (OR 2.4, P = 0.004), Colorectal Disease journal (OR 3.3, P = 0.005) and systematic review articles (OR 3.4, P = 0.009) were associated with higher citation levels.

CONCLUSION

Article exposure on Twitter was strongly associated with a high citation level. Medical communities should encourage journals as well as physicians to actively utilize social media to expedite the spread of new ideas and ultimately benefit medical society as a whole.

The Tingathe Surge: a multi-strategy approach to accelerate HIV case finding in Malawi

Setting

Nineteen health facilities in rural, southeastern Malawi.

Objective

To describe the implementation and results of a 6-week intervention to accelerate human immunodeficiency virus (HIV) case finding.

Design

Six HIV testing strategies were simultaneously implemented. Routinely collected data from Ministry of Health registers were used to determine the number of HIV tests performed and of new cases identified. The weekly averages of the total number of tests and new cases before and during the intervention were compared. Testing by age group and sex was described. The percentage yield of new cases was compared by testing strategy.

Results

Of 29 703 HIV tests conducted, 1106 (3.7%) were positive. Of the total number of persons tested, 69.5% were women and 75.5% were aged >15 years. The yield of positive test results was 3.5% among women, 4.3% among men, 4.4% among those aged >15 years and 1.5% among those aged ⩽15 years. The average weekly number of tests increased 106.7% from 3337 to 6896 (P = 0.002). The average weekly number of positive cases identified increased 51.9% from 158 to 240 (P = 0.017). The testing strategy with the highest yield resulted in a 6.0% yield; the lowest was 1.3%. The yield for all strategies, except one, was highest in adult men.

Conclusion

A multi-strategy approach to HIV testing and counseling can be an effective means of accelerating HIV case finding.

Production of Membrane Vesicles by Enterococcus faecium Cultured With or Without Subinhibitory Concentrations of Antibiotics and Their Pathological Effects on Epithelial Cells

Enterococcus faecium is a clinically important pathogen associated with opportunistic infection and multi-drug resistance. E. faecium has been shown to produce membrane vesicles (MVs), but MV production by E. faecium under antibiotic stress conditions and the pathogenic traits thereof have yet to be determined. This study investigated the production of MVs in E. faecium ATCC 700221 cultured with sub-minimum inhibitory concentrations (MICs) of vancomycin or linezolid and determined their pathologic effects on colon epithelial Caco-2 cells. E. faecium ATCC 700221 cultured with 1/2 MIC of vancomycin or linezolid produced 3.0 and 1.5 times more MV proteins than bacteria cultured without antibiotics, respectively. Totals of 438, 461, and 513 proteins were identified in MVs from E. faecium cultured in brain heart infusion broth (MVs/BHI), BHI broth with 1/2 MIC of vancomycin (MVs/VAN), or BHI broth with 1/2 MIC of linezolid (MVs/LIN), respectively. Intact MVs/BHI induced cytotoxicity and the expression of pro-inflammatory cytokine and chemokine genes in Caco-2 cells in a dose-dependent manner, but proteinase K-treated MVs significantly suppressed these pro-inflammatory responses. MVs/LIN were more cytotoxic toward Caco-2 cells than MVs/BHI and MVs/VAN, whereas MVs/VAN stimulated more pro-inflammatory cytokine gene expression in Caco-2 cells than MVs/BHI and MVs/LIN. Overall results indicated that antibiotics modulate the biogenesis and proteomes of MVs in E. faecium at subinhibitory concentrations. MVs produced by E. faecium cultured under antibiotic stress conditions induce strong host cell responses that may contribute to the pathogenesis E. faecium.

Clinical outcomes of radial probe endobronchial ultrasound using a guide sheath for diagnosis of peripheral lung lesions in patients with pulmonary emphysema

BACKGROUND

Generally, structural destruction of lung parenchyma, such as pulmonary emphysema, is considered to be related to the low diagnostic yields and high complication rates of lung biopsies of peripheral lung lesions. Currently, little is known about the clinical outcomes of using endobronchial ultrasound with a guide sheath (EBUS-GS) to diagnose peripheral lesions in patients with emphysema.

METHODS

This retrospective study was performed to identify the clinical outcomes of EBUS-GS in patients with pulmonary emphysema. This study included 393 consecutive patients who received EBUS-GS between February 2017 and April 2018. The patients were classified according to the severity of their emphysema, and factors possibly contributing to a successful EBUS-GS procedure were evaluated.

RESULTS

The overall diagnostic yield of EBUS-GS in patients with no or mild emphysema was significantly higher than in those with moderate or severe pulmonary emphysema (78% vs. 61%, P = 0.007). There were no procedure-related complications. The presence of a bronchus sign on CT (P <  0.001) and a "within the lesion" status on EBUS (P = 0.009) were independently associated with a successful EBUS-GS procedure. Although the diagnostic yield of EBUS-GS in patients with moderate-to-severe emphysema was relatively low, a bronchus sign and "within the lesion" status on EBUS were contributing factors for a successful EBUS-GS.

CONCLUSIONS

EBUS-GS is a safe procedure with an acceptable diagnostic yield, even when performed in patients with pulmonary emphysema. The presence of a bronchus sign and "within the lesion" status on EBUS were predictors of a successful procedure.

Factors predicting long-term survival of patients with sepsis on arrival at the emergency department: A single-center, observational study

Predicting long-term outcomes after sepsis is important when caring for patients with this condition. The purpose of the present study was to develop models predicting long-term mortality of patients with sepsis, including septic shock.Retrospective data from 446 patients with sepsis (60.8% men; median age, 71 years) treated at a single university-affiliated tertiary care hospital over 3 years were reviewed. Binary logistic regression was used to identify factors predicting mortality at 180 and 365 days after arrival at the emergency department. Long-term prognosis scores for the 180- and 365-day models were calculated by assigning points to variables according to their β coefficients.The 180- and 365-day mortality rates were 40.6% and 47.8%, respectively. Multivariate analysis identified the following factors for inclusion in the 180- and 365-day models: age ≥65 years, body mass index ≤18.5 kg/m, hemato-oncologic diseases as comorbidities, and ventilator care. Patients with scores of 0 to ≥3 had 180-day survival rates of 83.8%, 70.8%, 42.3%, and 25.0%, respectively, and 365-day survival rates of 72.1%, 64.6%, 36.2%, and 15.9%, respectively (all differences P < .001; log-rank test). The areas under the receiver operating characteristic curves of the 180- and 365-day models were 0.713 (95% confidence interval [CI] 0.668-0.756, P < .001) and 0.697 (95% CI 0.650-0.740, P < .001), respectively.These long-term prognosis models based on baseline patient characteristics and treatments are useful for predicting the 6- and 12-month mortality rates of patients with sepsis.

Inhibitory effects of thymol on the cytotoxicity and inflammatory responses induced by Staphylococcus aureus extracellular vesicles in cultured keratinocytes

Staphylococcus aureus extracellular vesicles (EVs) deliver effector molecules to host cells and induce host cell pathology. This study investigated the disruption of S. aureus EVs by thymol along with its inhibitory effects on the cytotoxicity and inflammatory responses induced by EVs derived from two different S. aureus strains in cultured keratinocytes. Membrane disruption of the S. aureus EVs treated with thymol was determined using transmission electron microscopy. Human keratinocyte HaCaT cells were incubated with either intact or thymol-treated S. aureus EVs and then analyzed for cytotoxicity and pro-inflammatory cytokine gene expression. Thymol inhibited the growth of S. aureus strains and disrupted the membranes of the S. aureus EVs. The cytotoxicity and the expression levels of the pro-inflammatory cytokine genes towards HaCaT cells differed between the EVs derived from two S. aureus strains. Thymol-treated S. aureus EVs inhibited the cytotoxicity and the expression of the pro-inflammatory cytokine genes when compared to intact S. aureus EVs. Thymol-treated S. aureus EVs delivered lesser amounts of the EV component to host cells than intact EVs. Our results suggest that the thymol-induced disruption of the S. aureus EVs inhibits the delivery of effector molecules to host cells, resulting in the suppression of cytotoxicity and inflammatory responses in keratinocytes. Thymol may attenuate the host cell pathology induced by an S. aureus infection via both the antimicrobial activity against the bacteria and the disruption of the secreted EVs.

The Infectivity of Pulmonary Tuberculosis in Korean Army Units: Evidence from Outbreak Investigations

Background

Tuberculosis (TB) causes substantial health burden to the Korean military. This study aims to assess the impact of infectious TB cases on close and casual contacts in the Korean Army settings based on contact investigation data.

Methods

Six Army units with infectious TB cases from September 2012 to May 2013 were enrolled in the study. We analyzed the clinical data from close and casual contacts screened using the tuberculin skin test (TST) and QuantiFERON-TB Gold In-Tube to identify latent tuberculosis infection (LTBI) cases. For the control group, 286 military conscripts with no reported TB exposure were tested by TST only.

Results

Of the 667 contacts of index cases, LTBI cases identified were as follows: 21.8% of close contacts of smear-positive cases (71/326), 8.5% of casual contacts of smear-positive cases (26/305), and 2.8% of close contacts of smear-negative cases (1/36). In the control group, 16.8% showed positivity in TST. In a multivariate analysis, having stayed in the same room or next room with TB patients was identified as a risk factor of LTBI.

Conclusion

Using the data from TB contact investigations in the Korean Army units, we found an overall LTBI rate of 14.7% among the contacts screened. This study demonstrates that contacts living in the same building, especially the same room or next room, with TB patients are at a high risk of acquiring LTBI, serving as additional evidence for defining close and casual contacts of a TB patient with regard to Army barrack settings.

Pseudorapidity Dependence of Particle Production and Elliptic Flow in Asymmetric Nuclear Collisions of p+Al, p+Au, d+Au, and ^{3}He+Au at sqrt[s_{NN}]=200 GeV

Asymmetric nuclear collisions of p+Al, p+Au, d+Au, and ^{3}He+Au at sqrt[s_{NN}]=200  GeV provide an excellent laboratory for understanding particle production, as well as exploring interactions among these particles after their initial creation in the collision. We present measurements of charged hadron production dN_{ch}/dη in all such collision systems over a broad pseudorapidity range and as a function of collision multiplicity. A simple wounded quark model is remarkably successful at describing the full data set. We also measure the elliptic flow v_{2} over a similarly broad pseudorapidity range. These measurements provide key constraints on models of particle emission and their translation into flow.

Radial probe endobronchial ultrasound using a guide sheath for peripheral lung lesions in beginners

Background

The diagnostic yields and safety profiles of transbronchial lung biopsy have not been evaluated in inexperienced physicians using the combined modality of radial probe endobronchial ultrasound and a guide sheath (EBUS-GS). This study assessed the utility and safety of EBUS-GS during the learning phase by referring to a database of performed EBUS-GS procedures.

Methods

From December 2015 to January 2017, all of the consecutive patients who underwent EBUS-GS were registered. During the study period, two physicians with no previous experience performed the procedure. To assess the diagnostic yields, learning curve, and safety profile of EBUS-GS performed by these inexperienced physicians, the first 100 consecutive EBUS-GS procedures were included in the evaluation.

Results

The overall diagnostic yield of EBUS-GS performed by two physicans in 200 patients with a peripheral lung lesion was 73.0%. Learning curve analyses showed that the diagnostic yields were stable, even when the procedure was performed by beginners. Complications related to EBUS-GS occurred in three patients (1.5%): pneumothorax developed in two patients (1%) and resolved spontaneously without chest tube drainage; another patient (0.5%) developed a pulmonary infection after EBUS-GS. There were no cases of pneumothorax requiring chest tube drainage, severe hemorrhage, respiratory failure, premature termination of the procedure, or procedure-related mortality.

Conclusions

EBUS-GS is a safe and stable procedure with an acceptable diagnostic yield, even when performed by physicians with no previous experience.

Electronic supplementary material

The online version of this article (10.1186/s12890-018-0704-7) contains supplementary material, which is available to authorized users.