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Antimicrobial resistance has become a severe threat to global public health. According to statistics, nearly 700,000 people die from bacterial infections worldwide (J.

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Min Zhang,1,2 Jia Li,3 Yuemei Lu,4 Weiyuan Wu,4 Jinsong Wu,4 Yanji Xu,1,5 Yuxin Zhong,1,2 Shiyi Liu,1,2 Chuchu Lin,6 Shuye Xu,3 Dandan Chen,1,2 Xuefeng Gao,7 Yutian Luo,8 Huaisheng Chen,8 Xueyan Liu,8 Wei Huang1,2 1Shenzhen People’s Hospital, Shenzhen Institute of Respiratory Diseases, Shenzhen, Guangdong, People’s Republic of China; 2Bacteriology & Antibacterial Resistance Surveillance Laboratory, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, People’s Republic of China; 3Department of Nosocomial Infection Control, Bengbu Third People’s Hospital, Bengbu, People’s Republic of China; 4Department of Clinical Microbiology, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, People’s Republic of China; 5Nanshan District Center of Chronic Disease Control, Shenzhen, People’s Republic of China; 6Department of Nosocomial Infection Control, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, People’s Republic of China; 7Department of Gastroenterology and Hepatology, Shenzhen University General Hospital, Shenzhen, People’s Republic of China; 8Department of Intensive Care Unit, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, People’s Republic of ChinaCorrespondence: Wei HuangBacteriology & Antibacterial Resistance Surveillance Laboratory, Shenzhen Institute of Respiratory Diseases, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University The First Affiliated Hospital, Southern University of Science and Technology), No. 1017 Dongmen North Road, Shenzhen People’s Hospital, Shenzhen, 518020, Guangdong, People’s Republic of ChinaTel +86 7522942513Fax +86 7522942514Email whuang_sz@163.comBackground: ST11 is the most prevalent sequence type of clinical Klebsiella pneumoniae in China.Methods: We investigated the characteristics of the ST11 subclones using core genome multi-locus sequence typing (cgMLST). Ninety-three carbapenemase-producing K. pneumoniae isolates were collected at Shenzhen People’s Hospital. Then, whole-genome sequencing and cgMLST were used to discriminate apparent subclones within the ST11 group.Results: We analyzed the prevalence and genetic relationships of these subclones. ST11 and K. pneumoniae carbapenemase (KPC-2) were the predominant genotype and carbapenemase, respectively, in the clinical carbapenemase-producing K. pneumoniae strains. cgMLST scheme genotyping divided the ST11 group into two clades across seven complex types (CTs). CT1313 was the most prevalent subclone. The deletion of galF and a high frequency of SNPs in genes associated with the stress- and SOS-responses were found in CT1291 and CT2405 over time, respectively.Conclusion: Our results indicated that the subclones of the ST11 group had different patterns of prevalence. Highly discriminatory genotyping techniques, such as cgMLST scheme, should be used in further molecular epidemiology investigations.Keywords: Klebsiella pneumoniae, whole genome sequencing, cgMLST, ST11, carbapenem-resistance

The threat of antimicrobial resistance calls for more efforts in basic science, drug discovery, and clinical development, particularly gram-negative carbapenem-resistant pathogens. We sought to identify novel antibacterial agents against Acinetobacter baumannii ATCC19606 using whole cell-based screening. A small molecule named 6D1 with the chemical structure of 6-fluorobenzo[d]isothiazol-3(2H)-one was identified and exhibited activity against A. baumannii ATCC19606 strain (minimal inhibitory concentration, MIC = 1 mg l−1). The mutation in the plasmid-derived ohrB gene that encodes a peroxidase was identified in spontaneously resistant mutants. Treatment of the bacteria with 6D1 resulted in increased sensitivity to peroxide, such as tert-butyl hydroperoxide. The binding of 6D1 and OhrB was confirmed by surface plasmon resonance. Interestingly, the MIC of kanamycin and gentamicin against spontaneously resistant mutants decreased. Finally, we identified the effect of 6D1 on enhancing the antibacterial activity of kanamycin and gentamicin, including against New Delhi metallo-β-lactamase (NDM-1)-producing carbapenem-resistant Klebsiella pneumoniae, but not in strains carrying aminoglycosides resistance genes. In this study, we identified a small molecule that suppresses the growth of A. baumannii, interacts with hydroperoxide reductase from A. baumannii ATCC19606 plasmid pMAC, and enhances the antibacterial activity of kanamycin and gentamicin. We propose that peroxidase may be potentially used as a target for aminoglycosides adjuvant development.

Objective We aimed to establish a tool for rapid identification of KL49 Acinetobacter baumannii. Methods Based on the capsular polysaccharide (CPS) synthesis genes database, we investigated the distribution of K locus type 49 (KL49) genes in other KL types and established a rapid identification method for KL49. We collected 61 clinical carbapenem-resistant A. baumannii (CRAB) strains, identified KL49 by gtr100 detection, and used whole genome sequencing (WGS) for verification. A mouse pneumonia model was used to confirm the hypervirulence phenotype. We tested the presence of gtr100 gene in 165 CRAB strains from three provinces in China and evaluated the correlation of gtr100 carrying CRAB infection with mortality. Results The gtr100 gene is the CPS synthesis gene found only in KL49. We screened out nine WGS-validated KL49 strains from 61 CRAB clinical strains using polymerase chain reaction (PCR) to detect the gtr100 gene. The survival rates of KL49 strains were significantly lower than nonKL49 strains in a mouse pneumonia model. The survival rates of LAC-4 gtr100 knockout strain decreased significantly. Analysis of phylogenetics showed the worldwide spread of KL49 A. baumannii. Infection of gtr100 carrying CRAB is an independent risk for mortality (OR, 10.76; 95%CI: 3.08-37.55; p

Wei Huang,1,2,* Jinyong Zhang,3,* Shiyi Liu,1 Chunxia Hu,1 Min Zhang,1 Shumin Cheng,1 Huijuan Yu,1,2 Manling Zheng,1 Jinsong Wu,2 Yuemei Lu,2 Quanming Zou,3 Ruiqin Cui1 1Bacteriology & Antibacterial Resistance Surveillance Laboratory, Shenzhen Institute of Respiratory Diseases, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University, The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, People’s Republic of China; 2Department of Clinical Microbiology, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University, The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, People’s Republic of China; 3National Engineering Research Center of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing, People’s Republic of China*These authors contributed equally to this workCorrespondence: Quanming Zou; Ruiqin Cui, Email qmzou2007@163.com; screening_sz@163.comBackground: The use of antibiotic adjuvants is a complementary strategy to the development of new antibiotics. The essential role of the ArnA dehydrogenase domain (ArnA_DH) in the addition of 4-amino-L-arabinose (L-Ara4N) to lipid A makes it a potential target in polymyxin adjuvant design.Purpose: This study aimed to identify a dehydrogenase inhibitor that enhances the antibacterial effect of polymyxin B (PB) and to further understand the mechanism of this drug combination.Methods: A susceptible K. pneumoniae strain, ATCC13883, was used to screen a dehydrogenase inhibitor library based on 3-(4,5)-dimethylthiazol(-z-y1)-2,5-diphenyltetrazolium bromide (MTT) and chequerboard assays. The protein- and cell-based effects of disulfiram (DSF) on ArnA activity were assessed, and the transcription levels of genes in the arn operon were evaluated by quantitative real-time polymerase chain reaction (qRT–PCR). Lipid A was isolated, and a structural analysis was performed. The cell wall function was evaluated through membrane integrity and bacterial viability assays. The in vivo antibacterial activity was evaluated using a mouse pulmonary infection model.Results: We screened a dehydrogenase inhibitor library and found that the anti-alcoholism drug DSF significantly enhanced the antibacterial activity of PB in vitro and in vivo. The protein-based enzyme activity assay showed that DSF exerted no direct effect on the dehydrogenase activity of ArnA. Treatment with the combination of DSF and PB but not with PB alone decreased both the transcription level of genes in the arn operon and the modification level of lipid A. DSF also strengthened the disruption of the cell membrane integrity of PB. Moreover, the enhanced PB antibacterial activity was effective against clinical PB-resistant strains.Conclusion: We identified a new drug combination that can be used to reduce the necessary dosage of PB and overcome PB resistance, and this drug combination has good prospects for clinical application.Keywords: polymyxins, antibiotic adjuvants, antibacterial, cell membrane

The ability of VITEK mass spectrometry (MS) in detection of bacterial resistance is currently under exploration and evaluation. In this study, we developed and validated a VITEK MS method to rapidly test carbapenemase-producing

Background Group B Streptococcus (GBS) is a leading cause of early-onset disease (EOD) and late-onset disease (LOD) in infants. We sought to investigate the antibiotic susceptibility profiles, resistance genes, virulence-related genes, serotype distribution and genotypic characteristics of GBS recovered from infected or colonized neonates and pregnant women in a tertiary teaching hospital in Shenzhen, China, from 2008 to 2015. Results High resistance rates of erythromycin (66.7–100%) were detected among early-onset GBS (EOGBS), late-onset GBS (LOGBS), neonatal colonizing GBS (NCGBS) and maternal colonizing GBS (MCGBS). 89.5–100% of four groups of GBS isolates showed resistance to tetracycline. More than 90 % of erythromycin resistant isolates of EOGBS (8/8, 100%), LOGBS (16/17, 94.1%) and NCGBS (10/11, 90.9%) harbored ermB, while only 9.1–17.6% harbored mefA/E. By contrast, 55.8% (24/43) and 62.8% (27/43) of erythromycin resistant MCGBS isolates carried ermB and mefA/E genes, respectively. The tetO gene was more common in tetracycline resistant EOGBS (10/11, 90.9%), LOGBS (17/17, 100%) and NCGBS (10/11, 90.9%), compared to tetracycline resistant MCGBS (12/51, 23.5%). Additionally, the tetM gene accounted for 90.9% (10/11), 76.5% (13/17), 45.5% (5/11) and 80.4% (41/51) of four groups of isolates, respectively. Serotype III was the most predominant in EOGBS (8/12, 66.7%) and LOGBS (15/17, 88.2%), while serotype Ib accounted for 50.0% (6/12) of NCGBS, and serotype Ia and III accounted for 45.6% (26/57) and 33.3% (19/57) of MCGBS, respectively. Sequence type 17 (ST17) was the most common in EOGBS (6/12, 50%) and LOGBS (12/17, 70.6%), while ST12 was predominant in NCGBS (5/12, 41.7%), and five STs (ST19, ST23, ST12, ST103 and ST485) accounted for 66.7% (38/57) of the MCGBS. All serotype III-ST17 isolates recovered from neonates were associated with invasive infections. Conclusions This study shows the meaningful differences in molecular mechanisms of resistance to erythromycin and tetracycline, and the prevalence of serotypes and STs among GBS recovered from neonates and pregnant women. ST17 is predominant in neonatal invasive GBS, but rare in NCGBS and MCGBS. Electronic supplementary material The online version of this article (10.1186/s12866-019-1551-2) contains supplementary material, which is available to authorized users.

Objective: Pulmonary infection is an important cause of morbidity and death in immunosuppressed patients. Recent studies showed that infections caused by Nocardia are quite rare, especially mixed infections with Nocardia and Mycobacterium Tuberculosis (MTB). This case emphasizes the importance of being alert to the possibility of co-infection in immunosuppressed patients. Case description: A 31-year-old female patient presented to the outpatient clinic with recurrent fever and cough. She had also suffered from Systemic Lupus Erythematosus (SLE) and type V lupus nephritis for 8 years. Additionally, she tested positive for the Nocardia nova complex and MTB following culture of the sputum/bronchoalveolar lavage fluid (BALF) and lung tissue. Initial Computed Tomography (CT) showed a bi-pulmonary massive high-density shadow with multiple cavities, Ground-Glass Opacity (GGO) and multiple miliary nodules. After admission, the patient was given Cefoperazone-Sulbactam (CSL) for empiric treatment and also received low-flow oxygen therapy. Four days later, microscopic examination suggested infection with Nocardia and CSL was replaced with Trimethoprim/Sulfamethoxazole (SXT), Moxifloxacin (MFX) and Imipenem (IPM). On the 9th day, the Nocardia nova complex was confirmed although there was a significant improvement in pulmonary symptoms and imaging results. However the images showed that there was no significant change in GGO and miliary nodules. Moreover, 18 days later she was confirmed with MTB infection and was subsequently transferred to the infectious diseases hospital for further treatment. Conclusion: Immunosuppressed patients have higher morbidity and mortality after opportunistic infection with pulmonary pathogens such as Nocardia and MTB. Therefore, early detection of pathogens and selection of appropriate antimicrobial therapy can significantly improve the prognosis.

BackgroundThe threat of antimicrobial resistance calls for more efforts in basic science, drug discovery, and clinical development, particularly gram-negative carbapenem-resistant pathogens.Objectives and methodsWhole-cell–based screening was performed to identify novel antibacterial agents against Acinetobacter baumannii ATCC19606. Spontaneously resistant mutant selection, whole-genome sequencing, and surface plasmon resonance were used for target identification and confirmation. Checkerboard titration assay was used for drug combination analysis.ResultsA small molecule named 6D1 with the chemical structure of 6-fluorobenzo[d]isothiazol-3(2H)-one was identified and exhibited activity against A. baumannii ATCC19606 strain (minimal inhibitory concentration, MIC = 1 mg/L). The mutation in the plasmid-derived ohrB gene that encodes a peroxidase was identified in spontaneously resistant mutants. Treatment of the bacteria with 6D1 resulted in increased sensitivity to peroxide such as tert-butyl hydroperoxide. The binding of 6D1 and OhrB was confirmed by surface plasmon resonance. Interestingly, the MIC of kanamycin against spontaneously resistant mutants decreased. Finally, we identified the effect of 6D1 on enhancing the antibacterial activity of kanamycin, including New Delhi metallo-β-lactamase (NDM-1)-producing carbapenem-resistant Klebsiella pneumoniae, but not in strains carrying kanamycin resistance genes.ConclusionsIn this study, we identified a peroxidase inhibitor that suppresses the growth of A. baumannii and enhances the antibacterial activity of kanamycin. We propose that peroxidase may be potentially used as a target for kanamycin adjuvant development.

BackgroundHypervirulent Klebsiella pneumoniae lacking classical virulence factors is uncommon, and the virulence mechanisms of this organism are not understood.MethodsFollowing a retrospective study of carbapenem-resistant K. pneumoniae based on core genome multilocus sequence typing (cgMLST), isolates that caused high mortality were investigated with a genome-wide association study (GWAS), proteome analysis and an animal model.ResultsThe sublineage of sequence type 11 (ST11) K. pneumoniae, which belongs to complex type 3176 (CT3176) and K-locus 47 (KL47), was highlighted due to the high mortality of infected patients. GWAS analysis showed that ampR was associated with the CT3176 isolates. In a mouse model, the mortality of ampR-carrying isolates was comparable to that of the typical hypervirulent isolate GM2. Even during the first 24 hours of infection, the bacterial load and pathological changes of the ampR-carrying isolates in the lungs were more severe than those of GM2. The ampR complement mutant was able to enhance the virulence of the KL47 isolate but not the virulence of KL1. Proteome analysis showed that the expression of WcaJ in the ampR+ isolates was significantly higher than that in the ampR− isolates, and this result was also confirmed by transcription tests and capsule staining. It is suggested that the enhancement of the initial stage of capsule synthesis may be the cause of the high virulence of these non-hypermucoviscous ST11 carbapenem-resistant K. pneumoniae isolates.ConclusionsNon-hypermucoviscous ST11 hypervirulent carbapenem-resistant K. pneumoniae warrants continued surveillance and investigation.

Background Acinetobacter baumannii is one of the most important microorganisms associated with hospital-acquired infections and nosocomial outbreaks.Aim We investigate a hypervirulent A. baumannii outbreak with aim to identify the transmission mediator.Methods We investigated an outbreak in respiratory intensive critical care unit (RICU) and respiratory medicine unit (RMU) based on whole genome sequencing (WGS) and epidemiology data. Virulence potential was performed in a mouse model.Results Eight and two CRAB isolates were isolated in RICU and RMU during August 2018. Four fatal cases were all involved in a transmission event. In vivo test confirmed the hypervirulence phenotype of the isolates. We inferred that the portable devices were probably the mediator of the transmission based on the transmission chain and epidemiology data. We isolated an hypervirulent CRAB from the screen of portable ventilator. Portable devices disinfection using vaporized hydrogen peroxide and avoiding the sharing of devices between general ward and ICU successfully blocked the further transmission.Conclusions An emerging hypervirulent A. baumannii with enhanced virulence has successfully colonized on the surface of mobile medical device. Sharing these mobile devices may lead to spread between the general ward and ICU. The new transmission chain construction tool is useful to the outbreak investigation.

Background Siblings share a unique and long-lasting relationship. Their involvement in the upbringing of an individual with a disability may lead to long-term positive developmental outcomes. The purpose of this systematic review is to summarize existing interventions where neurotypical (NT) siblings served as intervention agents to guide their brothers/sisters with Autism Spectrum Disorder (ASD). Methods Within this review we describe the training provided to NT siblings and how they delivered interventions to their brothers/sisters with ASD. We also summarize social validity outcomes to understand the social importance of the goals and effects as well as the social appropriateness of the intervention procedures from the perspectives of parents, siblings, and naive observers. Results The 16 included studies provided training of intervention strategies/skills (e.g., Stay-Play-Talk curriculum, delivering prompts and reinforcers, and giving play instructions) to NT siblings. After training, NT siblings implemented the intervention through play or other interactions with their siblings with ASD. Social validity outcomes from raters indicated the agreement on the intervention goals, appropriateness and acceptance of the procedures, and satisfaction of the behavioral changes of the included studies. Conclusion Findings from this systematic review should be used to guide the development of appropriate training for NT siblings and inform the procedures within interventions delivery. Limitations of existing studies and areas for future consideration are discussed.

Background Endometrial carcinoma is a prevalent form of cancer. In fact, its incidence ranks fourth among European and North American females. Moreover, it is the most common gynecological malignant disease. Laparotomy, bilateral salpingo-oophorectomy, total abdominal hysterectomy, etc were common methods adopted in conventional open surgery. Recent developments in laparoscopic surgery (LPS) has made it more effective. The present study aims to compare the outcomes between LPS and a conventional open surgical procedure to treat stage II endometrial carcinoma patients. Methods A comprehensive search will be conducted on Cochrane library, PubMed, Web of Science, EMBASE, and China National of Knowledge Infrastructure to collect LPS and conventional open surgery in treating stage II endometrial carcinoma. The search will consider all articles published since the inception of the databases till July 2021. A pair of scholars will perform independent screening of the literature and extracted data to evaluate the bias risk in the selected studies. Afterwards, RevMan5.3 software will be used to conduct a meta-analysis. Conclusion This study will conduct a meta-analysis to compare the clinical efficacy of LPS and conventional open surgery in the treatment of stage II endometrial carcinoma.

Background Particulate matter (PM) exposure is closely associated with male infertility. Even though an association between poor semen quality and PM exposure has been widely accepted, which and when the semen parameter could be affected are still controversial. The purpose of this study is to estimate the effects of PM exposure on semen quality in Huai'an, China. Objectives and methods The study included 1955 men with 2073 semen samples between 2015 and 2017 with moderate to high exposure to air pollution in Huai'an, China. Three multivariable linear regression models were used to conduct exposure-response analyses for PM exposure and semen quality and to estimate the influence during different exposure periods by every 15 days period before ejaculation in all participants group and normal semen quality participants group. Results The average age of the observations was 28.9 ± 5.4 old years and the average abstinence period was 4.2 ± 1.5 days. The results showed high correlations between both PM2.5 and PM10 exposures throughout entire spermatogenesis and the declines of sperm count (β: -0.93, p Conclusion The present study revealed that ambient PM exposure throughout spermatogenesis during a long period, especially at early and middle stage were adversely associated with semen quality, sperm count and sperm concentration in particular.

Acinetobacter baumannii is an important human pathogen due to its multi-drug resistance, but is usually with low-grade virulence. Although a mouse model revealed different virulence grades of clinical carbapenem-resistant A. baumannii (CRAB) strains, the genetic basis remains unknown. We collected 61 CRAB isolates from intensive care unit of Shenzhen People’s Hospital (Shenzhen, China), and analyzed them used whole genome sequencing (WGS), multilocus sequence typing (MLST) and core genome MLST (cgMLST), transmission chain reconstruction and Comparative genomic tools. A mouse pneumonia model was used to confirm the hypervirulent phenotype. Eleven complex types (CT) were identified based on core genome multilocus sequence typing scheme. CT512 showed higher transmissibility and bloodstream infection rates than other CTs. A genomic region Lyb-2-4 was shared by CT512 and CT2092 but not CT2085. The mortality rates of patient infected with CRAB harboring Lyb-2-4 was significantly higher than those infected with CRAB isolates without Lyb-2-4 (77.8% vs 24.5%, p < 0.01). In the mouse model, the survival rates of strains containing the Lyb-2-4 region (LAC-4, 5122 and 2092) were significantly lower than for strains without Lyb-2-4 (7152, 71517, 20859 and ATCC17978). One open reading frame (ORF) was a marker for the presence of Lyb-2-4, and PCR of a segment of this ORF, designated as hvcT, served as a tag for hypervirulent CRAB. Our study should be very useful in advising the clinician to implement medical intervention earlier, and also making the worldwide surveillance of these hypervirulent CRAB strains easier.IMPORTANCEHypervirulent CRAB strains are expected to pose a threat to human health because infection of these strains is associated with high mortality and multidrug resistance. The rapid hypervirulent CRAB identification assay will facilitate prompt medical intervention. Our findings should provoke surveillance for hypervirulent CRAB strains harboring Lyb-2-4 in other countries. Further research should focus on the mechanism of hypervirulence, the acquisition of this genomic region and the development of control measures to prevent further dissemination.

Table S1. The details of serotypes and genotypic characteristics of GBS recovered from neonates and pregnant women, respectively. The CPS types, sequence types, clonal complexes, and predominant CPS type-STs were listed. (DOCX 15 kb)

Table S2. The details of Clinical and biological characteristics of GBS neonatal infections. The sex, age, birth weight, gestational age, infections confirmed by culture, clinical signs of infection, targeted and empirical antibiotic treatment, and outcomes were listed. (DOCX 16 kb)

In this paper, carbon nanotubes (CNTs) were added to activated carbon to enhance the mesopores. At first, different amounts of CNTs were added to phenolic resin and composite spheres were synthesized by suspension polymerization. Then, by carbonizing these spheres at 600°C followed by steam activation at 850°C for more than 90 min, we prepared highly developed porous CNTs/activated carbon composite spheres. The composite spheres were characterized by a laser particle size analyzer, scanning electron microscopy, Raman spectrum, and nitrogen adsorption-desorption isotherms. Results showed that the composite spheres had good sphericity even with high proportion of CNTs (45 wt.%). Analysis also showed that the pore size distribution of the composite spheres containing CNTs was “multi-peak”, especially with 20–100-nm pores. The improved 20–100-nm porous structures in the composite spheres can be ascribed to aggregated pores of CNT bundles. The amount of vitamin B12 adsorbed on the 45 wt.% CNT composite spheres was as high as 32.38 mg/g. The spheres could be used as adsorbents for middle-molecular-weight toxins or large molecules in hemoperfusion.

Background. Spinal cord injury (SCI) leads to bowel dysfunction. Electroacupuncture (EA) may improve bowel function. Objective. To assess EA on daily rhythmicity of intestinal movement and circadian rhythmicity of colonic Per2 expression in rats with SCI. Methods. Rats were randomized to the sham, SCI, and SCI+EA groups. EA was performed at bilateral Zusanli point (ST36) during daytime (11:00–11:30) for 14 days following SCI. Intestinal transit and daily rhythmicity of intestinal movement were assessed. Circadian rhythmicity of colonic Per2 expression was assessed by real-time RT-PCR. Results. EA shortened the stool efflux time and increased the dry fecal weight within 24 h in SCI rats. Daily rhythmicity of intestinal movements was unaffected by SCI. The expression of colonic Per2 peaked at 20:00 and the nadir was observed at 8:00 in the SCI and sham groups. In the SCI+EA group, colonic Per2 expression peaked at 12:00 and 20:00, and the nadir was observed at 8:00. Conclusion. SCI did not change the circadian rhythmicity of colonic Per2 expression in rats, and daily intestinal movement rhythmicity was retained. EA changed the daily rhythmicity of intestinal movement and the circadian rhythmicity of colonic Per2 expression in rats with SCI, increasing Per2 expression shortly after EA treatment.

To investigate the clinical features, mechanism of resistance and molecular epidemiology of carbapenem-resistant Acinetobacter baumannii (CRAB) infections at Shenzhen People's Hospital during an 8-year period.A. baumannii isolates were recovered from nosocomial infections patients at this hospital from 2002 to 2009. The minimum inhibitory concentrations (MICs) of antimicrobial agents against A. baumannii isolates were detected by agar dilution method. Polymerase chain reaction (PCR) and DNA sequencing were used to examine the carbapenemase genotype among CRAB. All isolates were typed by pulse field gel electrophoresis (PFGE). Clinical cases of CRAB infections were retrospectively analyzed according to Chinese experts' consensus on diagnosis, treatments, preventions and controls of Acinetobacter baumannii infections in China.A total of 87 cases of CRAB nosocomial infections were diagnosed in this study. The most prominent infections caused by CRAB was lung infections, followed by bloodstream infections, wound infections and abdominal infections, accounting for 69.0%, 8.0%, 8.0% and 6.9% of 87 cases, respectively. Approximately 80.5% (70/87) of CRAB isolated from intensive care unit (ICU). A sharp increase of CRAB infections (42/87) occurred in 2009, with the majority of pulmonary infections (34/42). Genotyping by PFGE found eight distinct PFGE patterns among 87 isolates of CRAB. The prominent CRAB clone A, carrying a blaOXA-58-like carbapenemase gene, had been prevalent from 2002 to 2006 at this hospital. The CRAB clone C, harboring a blaOXA-23-like carbapenemase gene, as well as clone A became the prominent clones during 2007 to 2008. The CRAB clone D, carrying a blaOXA-23-like carbapenemase gene, replaced clone A and C, and became the dominant clone in 2009.The spread of the CRAB clone D harboring a blaOXA-23-like gene causes a rapid increase of CRAB infections at this hospital during 2009.

The high level of low density lipoprotein (LDL) in plasma is the main cause of atherosclerosis. Hemoperfusion is an ideal therapy to lower the level of LDL in human blood system while therapeutic effect is determined by the adsorbent. The adsorbent must have suitable pore structure and specific functional groups. Carbon nanotubes (CNTs) could be a new adsorbent material because CNTs have high specific surface area and they can be modified by a variety of functional groups. Porous carbon composite beads with the CNTs and phenolic resin mixture were synthesized by suspension polymerization, following with carbonization and steam-activation. Then the porous composite beads were sulfonated with a sulfanilic acid anhydrous by diazotization and coupling reaction. The potential application of the sulfonated porous composite beads in adsorbing low density lipoprotein (LDL) from human serum was investigated. The results showed that the sulfonic acid groups on the composite beads could lower LDL levels greatly by electrostatic interaction with electropositive LDL. The higher 20–100 nm pore volume the composite beads had, the more LDL they could adsorb. The 20–100 nm pore volume was enhanced by adding more CNTs and improving CNTs dispersion (ultrasonic crushing). The sulfonated composite beads containing 45 wt% CNTs presented the highest adsorption capacity to LDL 10.46 mg/g, showing a good prospect as LDL adsorbent in hemoperfusion.

Background Typhoid and paratyphoid fever are endemic in China. The objective of this investigation was to determine the molecular features of nalidixic acid-resistant Salmonella enteric serovar Typhi (S. typhi) and Paratyphi (S. paratyphi) from blood isolates in Shenzhen, China. Results Twenty-five S. typhi and 66 S. paratyphi were isolated from 91 bacteriemic patients between 2002 and 2007 at a hospital in Shenzhen, Southern China. Fifty-two percent (13/25) of S. typhi and 95.3% (61/64) of S. paratyphi A were resistant to nalidixic acid. Sixty-seven isolates of nalidixic acid-resistant Salmonella (NARS) showed decreased susceptibility to ciprofloxacin (MICs of 0.125-1 μg/mL). All 75 NARS isolates had a single substitution in the quinolone resistance-determining region (QRDR) of GyrA (Ser83→Phe/Pro/Tyr, or Asp87→Gly/Asn), and 90.7% of these isolates carried the substitution Ser83Phe in GyrA. No mutation was found in the QRDR of gyrB, parC, or parE. Plasmid mediated quinolone resistance genes including qnr and aac(6')-Ib-cr were not detected in any isolate. Twenty-two distinct pulsed field gel electrophoresis (PFGE) patterns were observed among S. typhi. Sixty-four isolates of S. paratyphi A belonged to one clone. Eighty-seven investigated inpatients were infected in the community. Six patients infected by S. paratyphi A had a travel history before infection. Conclusions Nalidixic acid-resistant S. typhi and S. paratyphi A blood isolates were highly prevalent in Shenzhen, China. PFGE showed the variable genetic diversity of nalidixic acid-resistant S. typhi and limited genetic diversity of nalidixic acid -resistant S. paratyphi A.