[Prevalence and antimicrobial susceptibility of Salmonella isolated from broiler whole production process in four provinces of China]

Objective: To determine the prevalence and antimicrobial susceptibility of Salmonella isolated from broiler production process in 4 provinces of China. Methods: Using convenience sampling method, 238 sample sites from broiler whole production process were chosen in Henan, Jiangsu, Heilongjiang and Shandong provinces in 2012. A total of 11 592 samples were collected and detected to analyze prevalence baseline, including 2 090 samples from breeding chicken farms and hatcheries, 1 421 samples from broiler farms, 5 610 samples from slaughterhouses and 2 471 samples from distribution and retail stores. All Salmonella strains were isolated through selective enrichment, and were serotyped according to Kauffmann-White scheme. The antimicrobial susceptibilities of selected Salmonella strains were determined by the broth microdilution method and fourteen antimicrobial agents were examined. Results: During incubation course, the average prevalence of Salmonella was 5.5% in feces of breeding hens, feces of chicks, and hatching eggs, 123 Salmonella strains were isolated. During cultivation course, the prevalence of Salmonella was 8.0% in feces from broiler farms, soil, feed, and workers, 114 Salmonella strains were isolated. During slaughter course, the prevalence of Salmonella was 24.9% in swabs pre-slaughter, dressed broiler carcasses, pre-cooled broiler carcasses, water from precooling pool, cutter and chipping boards, frozen chicken portions, and workers, 1 438 Salmonella strains were isolated. During distribution and sale course, the prevalence of Salmonella was 20.9% in transport carts, frozen chicken portions, retail chicken portions and workers, 551 Salmonella strains were isolated. The dominant Salmonella serotypes were Salmonella Enteritidis (n=1 229) and Salmonella Indiana (n=621). Among 1 231 examined strains, 97.2% Salmonella isolates were resistant to at least one antimicrobial, 69.9% Salmonella strains were multi-drug resistant isolates. Conclusion: Our findings indicated that Salmonella contamination was common and serious in commercial broiler whole production process in China, especially in the course of defeathering, precooling and selling. The environment of broiler farm is the important source of Salmonella contamination. Additionally, antibiotic resistance of Salmonella was serious for common antimicrobials and multi-drug resistant strains existed widespread, which can pose potential risk on public health and clinical therapy.

Assortment Optimization with Product Level Demand and Substitution Information

This article presents a mathematical model for jointly optimizing base stock levels for the multiple items subject to service level goals. The proposed model uses the expected demand and substitution probabilities between products as inputs and has been used to analyze the effects of demand variability on profitability under service level constraint. The results of the analysis demonstrate that neglecting customer-driven substitution or excluding the impacts of variability and correlations in demand leads to significantly inefficient assortments.

Sinus tarsi approach (STA) versus extensile lateral approach (ELA) for treatment of closed displaced intra-articular calcaneal fractures (DIACF): A meta-analysis

INTRODUCTION

Our aim was to compare the effect of sinus tarsi approach (STA) vs extensile lateral approach (ELA) for treatment of closed displaced intra-articular calcaneal fractures (DIACF) is still being debated.

MATERIALS AND METHODS

A thorough research was carried out in the MEDLINE, EMBASE and Cochrane library databases from inception to December 2016. Only prospective or retrospective comparative studies were selected in this meta-analysis. Two independent reviewers conducted literature search, data extraction and quality assessment. The primary outcomes were anatomical restoration and prevalence of complications. Secondary outcomes included operation time and functional recovery.

RESULTS

Four randomized controlled trials involving 326 patients and three cohort studies involving 206 patients were included. STA technique for DIACFs led to a decline in both operation time and incidence of complications. There were no significant differences between the groups in American Orthopedic Foot and Ankle Society scores, nor changes in Böhler angle.

CONCLUSIONS

This meta-analysis suggests that STA technique may reduce the operation time and incidence of complications. In conclusion, STA technique is reasonably an optimal choice for DIACF.

[Surveillance of contamination level and antimicrobial resistance analysis of Salmonella on broiler carcasses after chilling in 4 poultry slaughterhouses of Henan Province]

Objective: Tests were carried out for obtaining contamination level and antimicrobial resistance of Salmonella on broiler carcasses after chilling in four poultry slaughterhouses in Henan. Methods: Totally, two hundred sixty nine broiler carcasses after chilling were collected in four slaughterhouses with the daily slaughter amount around 15 000 to 50 000. For qualitative analysis of Salmonella EFSA method was used and for quantitative analysis of Salmonella modified Rappaport-Vassiliadis most probable number (MSRV-MPN) method was used. All of the isolates were subjected to antimicrobial susceptibility testing of 8 antibiotics by minimum inhibitory concentration (MIC). Results: Overall, 48.7% (131/269) of the broiler carcasses after chilling were contaminated by Salmonella, and the average of contamination level is 1.32 most probable number MPN/g. Eight serotypes were detected. The dominant serotype is Salmonella enteritidis (93, 71.0%) followed by Salmonella Indiana (21, 16.0%). Only 2 (1.5%) Salmonella enteritidis strains were sensitive to all the tested antibiotics and the remaining 129 isolates were resistant to at least one kind of eight class antibiotics. Among them, resistant to NAL was the common (104, 79.4%) and 51 (38.9%) Salmonella isolates were multidrug-resistant. Conclusion: The contamination rate and multiple antimicrobial resistant of Salmonella on broiler carcasses after chilling from slaughterhouses was very serious, while the isolates contained various serotypes.

Transcriptomic analysis of KSHV-infected primary oral fibroblasts: The role of interferon-induced genes in the latency of oncogenic virus

The Kaposi sarcoma-associated herpesvirus (KSHV) is the causative agent of Kaposi sarcoma (KS), the most common HIV/AIDS-associated tumor worldwide. Involvement of the oral cavity portends a poor prognosis for patients with KS, but the mechanisms for KSHV regulation of the oral tumor microenvironment are largely unknown. Infiltrating fibroblasts are found within KS lesions, and KSHV can establish latent infection within human primary fibroblasts in vitro and in vivo, but contributions for KSHV-infected fibroblasts to the KS microenvironment have not been previously characterized. In the present study, we used Illumina microarray to determine global gene expression changes in KSHV-infected primary human oral fibroblasts (PDLF and HGF). Among significantly altered candidates, we found that a series of interferon-induced genes were strongly up-regulated in these KSHV-infected oral cells. Interestingly, some of these genes in particular ISG15 and ISG20 are required for maintenance of virus latency through regulation of specific KSHV microRNAs. Our data indicate that oral fibroblasts may represent one important host cellular defense component against viral infection, as well as acting as a reservoir for herpesvirus lifelong infection in the oral cavity.

Nonlinear mode interaction in equal-leg angle struts susceptible to cellular buckling

A variational model that describes the interactive buckling of a thin-walled equal-leg angle strut under pure axial compression is presented. A formulation combining the Rayleigh-Ritz method and continuous displacement functions is used to derive a system of differential and integral equilibrium equations for the structural component. Solving the equations using numerical continuation reveals progressive cellular buckling (or snaking) arising from the nonlinear interaction between the weak-axis flexural buckling mode and the strong-axis flexural-torsional buckling mode for the first time-the resulting behaviour being highly unstable. Physical experiments conducted on 10 cold-formed steel specimens are presented and the results show good agreement with the variational model.

[The expression of IL-22 in nasal polyps tissues]

Objective:To analyze the expression of IL-22 in nasal polyps and the expression of Th22 cells. Method:The concentrations of IL-22 in nasal polyps were determined by ELISA. The mononuclear cells infiltrated in nasal polyps were separated and flow cytometry was used to analyze the expression of IL-22 in CD4+ T cells and the counts of Th22 cells. Result:Compared with the control group, the expression of IL-22 in nasal polyps did not change significantly, however the expression of IL-22 in CD4+ T cells increased. Furthermore the number of Th22 cells in the tissue increased significantly. Conclusion:The expression of Th22 cells in nasal polyps is significantly increased, which may play an important role in local chronic inflammatory mucosal immunity.

Safety and efficacy of telbivudine for chronic hepatitis B during the entire pregnancy: Long-term follow-up

The management of hepatitis B virus (HBV) infection in pregnancy is a unique issue. Telbivudine (LdT) is recommended to block HBV mother-to-child transmission (MTCT) in the third trimester. However, the safety of LdT treatment during the entire pregnancy for the long-term growth of infants is unclear. The aim of this study was to evaluate the efficacy and long-term safety of LdT for the entire pregnancy period. This retrospective cohort study included 40 pregnant women and 43 children from 2011 to 2017. The antiviral effects and maternal abnormalities were evaluated. In addition, adverse events regarding infants at delivery and HBV vaccination outcomes were recorded. The status of physical development in the children during follow-up was also evaluated. Among pregnant women, the rates of HBV DNA flare were 5.00% during pregnancy and 7.50% postpartum, and the HBeAg seroconversion rates were 7.50% during pregnancy and 7.50% postpartum. No severe maternal abnormalities were observed. Regarding the infants, no one was positive for HBsAg, and only one infant was negative for anti-HBs in children over 7 months of age. Furthermore, no birth defects or severe adverse events were observed at delivery, and 97.67% normal height and 93.02% normal weight in children were observed on follow-up until 5 years of age. In conclusion, LdT use for the entire pregnancy is both effective for treating pregnant women and blocking HBV MTCT. Moreover, LdT is safe for women and infants. Most importantly, the long-term follow-up indicated that LdT is safe and does not affect the growth of children.

Route towards the optimization at given power of thermoelectric heat engines with broken time-reversal symmetry

We investigate the performance at a given power of a thermoelectric heat engine with broken time-reversal symmetry, and derive analytically the efficiency at a given power of a thermoelectric generator within linear irreversible thermodynamics. A universal bound on the efficiency of the thermoelectric heat engine is achieved under a strong constraint on the Onsager coefficients, and some interesting features are further revealed. Our results demonstrate that there exists a trade-off between efficiency and power output, and the efficiency at a given power may surpass the Curzon-Ahlborn limit due to broken time-reversal symmetry. Moreover, optimal efficiency at a given power can be achieved, which indicates that broken time-reversal symmetry offers physically allowed ways to optimize the performance of heat engines. Our study may contribute to the interesting guidelines for optimizing actual engines.

Ultrasonic defect characterization using parametric-manifold mapping

The aim of ultrasonic non-destructive evaluation includes the detection and characterization of defects, and an understanding of the nature of defects is essential for the assessment of structural integrity in safety critical systems. In general, the defect characterization challenge involves an estimation of defect parameters from measured data. In this paper, we explore the extent to which defects can be characterized by their ultrasonic scattering behaviour. Given a number of ultrasonic measurements, we show that characterization information can be extracted by projecting the measurement onto a parametric manifold in principal component space. We show that this manifold represents the entirety of the characterization information available from far-field harmonic ultrasound. We seek to understand the nature of this information and hence provide definitive statements on the defect characterization performance that is, in principle, extractable from typical measurement scenarios. In experiments, the characterization problem of surface-breaking cracks and the more general problem of elliptical voids are studied, and a good agreement is achieved between the actual parameter values and the characterization results. The nature of the parametric manifold enables us to explain and quantify why some defects are relatively easy to characterize, whereas others are inherently challenging.

[Molecular characterization genetic diversity of extended-spectrum β-lactamases-harboring conjugative plasmids identified in multi-drug resistant Escherichia coli isolated from food in China]

Objective: The purpose of this study was to investigate the molecular characteristics of ESBL-encoding conjugative plasmid identified in muti-drug resistant Escherichia coli isolated from food. Methods: 465 Escherichia coli isolates were collected from national foodborne disease surveillance net from 2013 to 2014 (salad, n=159; meat, n=102; processed meat, n=95; cakes/rice, n=46; cooked dish, n=63). ESBLs strain was detected by Mueller-Hinton agar plate, and then its drug resistance was tested by agar dilution method. Polymerase chain reaction (PCR) and DNA sequencing were performed to identify the corresponding ESBL genes. Plasmids were typed by PCR-based replicon typing and their characteristics were determined by S1-nuclease pulsed-field gel electrophoresis method. Broth mating assays were carried out for all isolates to determine whether the ESBL marker could be transferred by conjugation. Results: 12 E. coli were found to be resistant to cefotaxime, and all of which were confirmed as ESBLs. The 12 isolates all carried different types of CTX-M genes resistant to drug, and 7 of which carried TEM type as well. All 12 isolates contained at least one plasmid and some had four plasmids, with size ranging from 47-to 220-kb by S1-PFGE anaylsis. Seven isolates demonstrated the ability to transfer their cefotaxime resistance marker to the recotper strain J53 by only one plasmid. Conclusion: This study highlights the diversity of the multi-drug resistant E. coli and also the diversity of ESBL genes in China. Plasmids carrying these genes poses a serious threat to food safety in China.

Scattering and plasmonic synergetic enhancement of the performance of dye-sensitized solar cells by double-shell SiO2@Au@TiO2 microspheres

The Au nanoparticle sandwich double spheric-shells of SiO₂@Au@TiO₂ (SAT) microspheres are synthesized. The significant influence of the SAT microspheres on the properties of dye-sensitized solar cells (DSSCs) is investigated. Studies indicate that the introduction of SAT markedly enhanced the light scattering and capture ability of DSSCs and thus photogenerated electrons. DSSCs doped with 2.25 wt% SAT exhibit a maximum short circuit current density of 17.0 mA cm^-2 and photoelectric conversion efficiency of 7.14%, which are remarkably higher than those of conventional DSSCs at 15.7% and 21.2%, respectively. The marked enhancement in the performance of the optimal DSSCs can be attributed to the synergetic complementary effect of the enhanced light scattering of the microspheres and to the localized surface plasmon resonance of the Au nanoparticles in the SAT, and is a novel promising way of enhancing the performance of DSSCs.

Retrospective analysis of risk factors associated with Kawasaki disease in China

In order to provide early intervention for coronary artery lesion (CAL) caused by Kawasaki Disease (KD), we analyzed clinical characteristics of typical and incomplete KD cases from 1998 to 2008 in Northwest and Central China. A total of 383 patients included 298 cases of typical KD and 85 cases of incomplete KD. The morbidity of incomplete KD was 28.5%, a percentage significantly lower than that of typical KD. The occurrence of bulbar conjunctiva congestion, erythra, crissum red, film-like decrustation, lip red, rhagades, raspberry tongue, bilateral toe-end decrustation, limb sclerosis, cervical lymph nodes enlargement, agitation and irritability in incomplete KD group was lower than that in the group of typical KD (p < 0.05); however, the occurrence of unilateral toe-end decrustation, scar reappearance erythema, malaise, fatigue, liver incidence was significant higher in incomplete KD group (p < 0.05). Based on lab assays and inspection index comparisons, the incomplete KD cases whose C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were significantly increased, had significantly higher reduction in blood platelet (PLT). Interestingly, the KD patients with CPR higher than 30 mg/L, ESR higher than 40 mm/h, hepatomegaly and IVIG ineffectiveness, had higher incidence of CAL development. Altogether, our data have indicated differential clinical characteristics between incomplete KD and typical KD, and have identified several high risk factors of KD for CAL, such as hepatomegaly.

Performance optimization of dye-sensitized solar cells by multilayer gradient scattering architecture of TiO2 microspheres

TiO₂ microspheres (TMSs) with unique hierarchical structure and unusual high specific surface area are synthesized and incorporated into a photoanode in various TMS multilayer gradient architectures to form novel photoanodes and dye-sensitized solar cells (DSSCs). Significant influences of these architectures on the photoelectric properties of DSSCs are obtained. The DSSC with the optimal TMS gradient-ascent architecture of M036 has the largest amounts of dye absorption, strongest light absorption, longest electron lifetime and lowest electron recombination, and thus exhibits the maximum short circuit current density (J_sc) of 16.49 mA cm^-2 and photoelectric conversion efficiency (η) of 7.01%, notably higher than those of conventional DSSCs by 21% and 22%, respectively. These notable improvements in the properties of DSSCs can be attributed to the TMS gradient-ascent architecture of M036 which can most effectively increase dye absorption and localize incident light within the photoanode by the light scattering of TMSs, and thus utilize the incident light thoroughly. This study provides an optimized and universal configuration for the scattering microspheres incorporated in the hybrid photoanode, which can significantly improve the performance of DSSCs.

Critical roles of conventional dendritic cells in promoting T cell-dependent hepatitis through regulating natural killer T cells

Dendritic cells (DCs) play critical roles in initiating and regulating innate immunity as well as adaptive immune responses. However, the role of conventional dendritic cells (cDCs) in concanavalin A (ConA)-induced fulminant hepatitis is unknown. In this study, we demonstrated that depletion of cDCs using either CD11c-diphtheria toxin receptor transgenic mice (DTR Tg) mice or anti-CD11c antibody reduced the severity of liver injury significantly, indicating a detrimental role of cDCs in ConA-induced hepatitis. We elucidated further the pathological role of cDCs as being the critical source of interleukin (IL)-12, which induced the secretion of interferon (IFN)-γ by natural killer (NK) T cells. Reconstitution of cDCs-depleted mice with IL-12 restored ConA-induced hepatitis significantly. Furthermore, we determined that NK T cells were the target of DC-derived IL-12, and NK T cells contributed to liver inflammation and injury through production of IFN-γ. In summary, our study demonstrated a novel function of cDCs in mediating ConA-induced hepatitis through regulating IFN-γ secretion of NK T cells in an IL-12-dependent fashion. Targeting cDCs might provide potentially therapeutic applications in treating autoimmune related liver diseases.