Search

Introduction: Poor literacy is associated with hepatitis morbidity and mortality. Adolescents are especially at risk of hepatitis C. This study investigated viral hepatitis literacy, risk, and influencing factors among Chinese middle and high school students. Methodology: A supervised self-administered survey was conducted with school children from six schools in Shantou, China. Data on demographics, health literacy, and risk of viral hepatitis were analyzed. Results: A total of 1732 students (from three middle and three high schools) participated in the study. Their major information resources were the internet (39.5%, 685/1732), television (28.8%, 498/1732), family (27.7%, 479/1732), and school (21.2%, 368/1732). The mean literacy score on the manifestations and risk factors of hepatitis was 3.4 ± 2.2 and 4.0 ± 2.3 (out of 8), respectively. Multiple linear regression models showed being female and in high school, having parents with higher education levels, and school or clinicians as an information resource were independent positive predictors, whereas poor awareness of risk factors was a negative predictor for health literacy. Conclusions: We report the risk of hepatitis among Chinese middle and high school students due to limited literacy and poor attitudes towards health-risk behaviors. Health education in school is recommended for preventable health risks among Chinese adolescents.

Introduction: Students from Shantou University Medical College were subject to domicile quarantine during the early phase of the COVID-19 outbreak. Methodology: We investigated their experience during March-April 2020 using a cross-sectional, self-administered, anonymous online survey. Results: Out of 531 respondents, 75.7% became aware of the outbreak via the Internet (61.7%), WeChat (57.8%), and Weibo (49%). Nearly all students knew COVID-19 manifestations, incubation period, and transmission modes; about half considered wearing facemask and hand hygiene as effective epidemic interventions. They experienced various emotional reactions that changed significantly in response to the outbreak, lockdown, and quarantine (ps < 0.001), with depression in 23.3%. Most students (83.4%-99.4%) had positive attitudes and good compliance towards domicile quarantine and preventive measures. Females were significantly better than males in hand hygiene compliance (p = 0.04). More students with positive attitudes and good compliance than those without educated their families (ps < 0.05 – ps < 0.001). Multiple logistic regression showed negative relationships between anger and hand hygiene attitude (OR = 0.06, 95% CI = 0.01-0.87); confusion and quarantine compliance (0.30, 0.12-0.76); and anger and compliance with quarantine (0.32, 0.11-0.93), facemask (0.12, 0.03-0.50), and hand hygiene (0.27, 0.08-0.88). Conclusions: This study revealed how multichannel risk communication, early awareness, positive attitudes, and conformity of medical college students might have contributed to the favorable outcome from the COVID-19 epidemic in China. Clear, accurate, consistent, early risk communication by the local, national, and international public health authorities seems critical to promote public understanding, correct risk perception, and rational emotions and attitudes, leading to optimal conformity.

Background China has 129 dialects with Mandarin as the standard and Chaoshan as the major dialect of the Chaoshan region in Guangdong. This study aimed to describe the dialect competence and usage, communication difficulty, impact of linguistic barriers, and subjective experience in healthcare. Methods Healthcare providers (n = 234) and healthcare consumers (n = 483) at two tertiary teaching hospitals in Shantou, Chaoshan region participated in an anonymous survey. Results Chaoshan and Mandarin were spoken respectively by ca. 80% and 6.1% of the participants. Monolinguals accounted for 28.5%, including 16.8% of Chaoshan-speaking healthcare providers and 18% of Mandarin-speaking healthcare consumers. The monolinguals preferentially used their competent dialect (Ps Ps Ps Conclusions This is the first report of significant linguistic barriers in healthcare imposed by Mandarin and Chaoshan dialects in Chaoshan, China. With perceived adverse impacts on the entire healthcare delivery and risks to the healthcare quality and burden, interventions such as professional interpreter service, service-learning interpreter program, or mobile interpreting apps that are medically accurate and culturally sensitive are suggested for dialectally diverse China.

Background Seeking online health information (OHI) has become a common practice globally. The information seekers could face health risks if they are not proficient in OHI literacy. The OHI-seeking behaviors and skills of Chinese college students, the largest proportion of college students in the world, are understudied. This study was aimed to describe OHI-seeking behaviors and skills of college students in Guangdong, China. Methods College students in the Guangdong province with OHI-seeking experience were invited via WeChat, QQ, and Sina Weibo using QR code posters and flyers for participation in this online anonymized questionnaire-based study. Data on demographics, OHI literacy, information resources, search approaches, and behaviors were collected. The relationship between perceived OHI literacy and high-risk behaviors was investigated by bivariate logistic regression analysis. Results Respondents were 1203 college students with a mean age of 20.6 years, females (60.2%), and undergraduates (97.2%). They sought health information via websites (20.3%), WeChat (2.6%), or both (77.1%). Baidu was the main search engine, and baike.baidu.com (80.3%), Zhihu.com (48.4%), and Zhidao.baidu.com (35.8%) were top three among 20 searched websites for information about self-care (80.7%), general health (79.5%), disease prevention (77.7%), self-medication (61.2%), family treatment (40.9%), drugs (37.7%), western medications (26.6%), hospitals (22.7%), physicians (21.4%), and Traditional Chinese Medicine (15.6%). Despite most respondents (78%) lacked confidence in the evidence quality and satisfaction with the results, only 32.4% further consulted doctors. Many (> 50%) would recommend the retrieved information to others. About 20% experienced hacking/Internet fraud. Cronbach’s alpha for the internal consistency of OHI literacy was 0.786. Bivariate logistic regression analysis showed that students who believed they can judge the evidence level of OHI were more likely to self-diagnose (OR = 2.2, 95%CI, 1.6–3.1) and look for drug usage (OR = 3.1, 95%CI, 1.9–5.0). Conclusions This study reveals Chinese college students’ heavy reliance on OHI to manage their own and others’ health without sufficient knowledge/skills to identify misinformation and disinformation. The apparent risky information-seeking behaviors of Chinese college students warrant the provision of regulated, accurate, and actionable health information; assurance of cybersecurity; and health information literacy promotion in colleges by concerned authorities.

Achieving smoke-free healthcare facilities remains a great challenge in countries with a high smoking prevalence and weak regulation. Assessment of the impact of environmental tobacco smoke (ETS) and its constituent PM2.5 on the air quality in Chinese hospitals has not been reported. In this study, we conducted air quality surveys by measuring real-time PM2.5 concentrations with Dylos Air Quality Monitors in five tertiary hospitals in Shantou, China during summer (July-August 2016) and winter (November-February 2017). Twenty-eight-day surveys inside the hospitals showed median PM2.5 concentrations above the China Air Quality Standard in elevator lobbies (51.0 μg/m3, IQR 34.5–91.7), restrooms (40.2, 27.1–70.3), and corridors (36.5, 23.0–77.4). Evidence of tobacco smoking was significantly associated with PM2.5 spikes observed in all the survey locations, contributing to the air quality undesirable for health in 49.1% of total survey hours or 29.3% of summer and 75.4% of winter survey hours inside the buildings, and 33.5%, 25.7%, and 6.8% of survey hours in doctor offices, nurse stations, and patient rooms, respectively. In conclusion, smoking inside hospitals induces PM2.5 spikes that significantly compromise the air quality and impose significant health risk to the hospital inhabitants. Reinforcing comprehensive smoking ban with the vested interest of all stakeholders followed by creative disciplinary actions are suggested to ensure healthcare safety.

Background: Hepatitis C virus (HCV) infection is prevalent worldwide, especially among drug users. The epidemiology of HCV is rarely reported among drug users in developing countries, including China. Objectives: We aimed to describe the seroepidemiology of HCV infection in drug users at a Detoxification Center in Southeast China. Methods: With approval from the Shantou Center for Disease Control, the archived data of drug users (n = 5,228) at the largest monitored-detoxification center in Shantou during 2011 - 2017 were analyzed for demographics, risk behaviors, and HCV serology. Results: Among HCV-tested drug users, 36.9% (1930/5228) were people who inject drugs (PWID). The mean annual HCV seroprevalence rate over the seven-year study period was 36.3% for all drug users, including 67.3% and 16.6% for PWID and non-PWID, respectively, with the highest prevalence (78.1%) in 2017 and the lowest prevalence (58.6%) in 2015 for PWID. Independent risk factors of HCV infection identified by multiple logistic regression analysis were engaging in unprotected sex (OR = 1.553, 95% CI = 1.078 - 2.236), injecting drugs (10.28, 8.98 - 11.763), and sharing needles/syringes (2.24, 1.129 - 4.445) for all drug users and sharing needles/syringes (2.062, 1.438 - 2.957) for PWID. Conclusions: This study reports the seroepidemiology of drug users in the monitored Detoxification Center in Southeast China. A relatively high HCV positivity rate, especially among PWID, their high-risk behaviors and low education, and lack of institutional interventions of HCV monitoring and transmission call for government-sponsored educational programs to raise drug users’ awareness of the risk of HCV infection and other co-infections and monitoring of the infectious status and treatment of HCV-infected drug users.

Global Pharma Health Fund (GPHF) Minilab™, a semi-quantitative thin-layer chromatography (TLC)–based commercially available test kit, is widely used in drug quality surveillance globally, but its diagnostic accuracy is unclear. We investigated the diagnostic accuracy of Minilab system for antimicrobials, using high-performance liquid chromatography (HPLC) as reference standard. Following the Minilab protocols and the Pharmacopoeia of the People’s Republic of China protocols, Minilab-TLC and HPLC were used to test five common antimicrobials (506 batches) for relative concentration of active pharmaceutical ingredients. The prevalence of poor-quality antimicrobials determined, respectively, by Minilab TLC and HPLC was amoxicillin (0% versus 14.9%), azithromycin (0% versus 17.4%), cefuroxime axetil (14.3% versus 0%), levofloxacin (0% versus 3.0%), and metronidazole (0% versus 38.0%). The Minilab TLC had false-positive and false-negative detection rates of 2.6% (13/506) and 15.2% (77/506) accordingly, resulting in the following test characteristics: sensitivity 0%, specificity 97.0%, positive predictive value 0, negative predictive value 0.8, positive likelihood ratio 0, negative likelihood ratio 1.0, diagnostic odds ratio 0, and adjusted diagnostic odds ratio 0.2. This study demonstrates unsatisfying diagnostic accuracy of Minilab system in screening poor-quality antimicrobials of common use. Using Minilab as a stand-alone system for monitoring drug quality should be reconsidered.

SummaryDespite Clostridium difficile infection (CDI) being a common cause of diarrhoea in hospitals worldwide, diagnostic testing or management guidelines are not available in most hospitals in China. In this prospective two-year study, the incidence of CDI among 276 patients with watery diarrhoea was 23.1%. Lack of diagnostic testing for CDI was associated with improper management in 26.4% of patients, risk of nosocomial transmission from lack of isolation precautions, and risk of community transmission from discharging symptomatic toxigenic C. difficile carriers. Updating practice guidelines in line with the current evidence and implementing diagnostic testing for CDI are recommended in hospitals in China.

Background Nasal colonization with bacterial pathogens is associated with risk of invasive respiratory tract infections, but the related information for Chinese healthy children is scarce. Methods This cross-sectional study was conducted with healthy children from 6 kindergartens in the Chaoshan region, southern China during 2011–2012. Nasal swabs were examined for five common bacterial pathogens: Streptococcus pneumoniae, Haemophilus influenzae, Haemophilus parainfluenzae, Moraxella catarrhalis, and Staphylococcus aureus. Results Among 1,088 children enrolled, 79.6 % (866) were target-bacterial carriers, of which 34.4 % (298/866) were positive for ≥2 bacteria species. The most common pathogen in the bacterial carriers was M. catarrhalis (76.6 %), followed by S. pneumoniae (26.6 %), S. aureus (21.8 %), H. parainfluenzae (12.7 %), and H. influenzae (2.3 %). Multiple logistic regression analyses showed negative associations between age and the overall or multiple bacterial carriage, and between the father’s education level and multiple bacterial carriage (all p

BackgroundSelf-medication with antibiotics (SMA) has been reported among university students in many countries, but little research has been done on this issue in China. The objective of this study was to evaluate knowledge and behaviors of university students and risk factors concerning SMA.Methodology/principal findingsUsing a novel questionnaire-based data collection instrument, an anonymous online survey was conducted with the students of Shantou University (STU), a university comprising 8 schools/colleges in eastern Guangdong, China. Of 1,300 respondents (13.8% of total eligible participants), 47.8% had self-treated with antibiotics. Logistic regression analysis identified prior knowledge of antibiotics (PKA), older age, and higher monthly allowance as independent risk factors for SMA. PKA significantly influenced students' knowledge about antibiotics, their uses, and common adverse reactions (all pConclusionsHigh prevalence of SMA was noted among STU students. Presence of risk factors and risk-associated behaviors/attitudes in the study population calls for focused educational intervention and stricter governmental legislation and regulation of antibiotic use and sale in pharmacies.

We characterized 53 Salmonella enterica ser. Typhimurium strains recovered from healthy pigs during 1998-1999 (n=12) and 2004-2005 (n=41) as to their carriage of DT104 spacer region, class 1 and 2 integrons, virulence genes (spvC, rck, and pefA), and XbaI- and BlnI-Pulsed-Field Gel Electrophoresis (PFGE) profiles. No DT104 strain was detected in 1998-1999, whereas 65.9% (27/41) of the strains in 2004-2005 were DT104 showing resistance to ampicillin, chloramphenicol, streptomycin, sulfonamides, tetracycline, and cephaloridine (R-type ACSSuT+). Class 1 intergron-associated genes, aadA2 (1.0-kbp amplicon) and pse1 (1.2-kbp amplicon), were found in all the DT104 strains (27/27). One strain showing resistance to streptomycin, sulfonamides, tetracyclin, and trimethoprim (R-type SsuTTm) harbored another class 1 integron-associated gene (dhfrXII-orfF- aadA2) on 1.9-kbp amplicon. Virulence gene spvC was found in 92.5% (49/53) and rck and pefA were found in 88.7% (47/53) of the strains, whereas spvC, rck, and pefA were found in all the DT104 strains. Ser. Typhimurium strains were categorized into four clusters (X1, X2, X3, and X4a/X4b) by XbaI-PFGE, or into nine clusters (B1, B2, B3a/B3b, B4, B5, B6, B7, B8, B9a/B9b) by BlnI-PFGE analyses. DT104 strains were restricted into X2, or into B2, B3a/B3b, and B6 clusters, indicating that our multidrug-resistant DT104 strains from healthy pigs might have derived from at least three independent clones, with the most widespread clone being the cluster B6 strains isolated in Kanto, Tokai, Chugoku, and Kyushu regions.

Staphylococcus aureus, Staphylococcus hyicus, and Staphylococcus chromogenes are known to cause skin infections in human or animals by producing exfoliative toxins (ETs). Staphylococcus pseudintermedius can also cause canine pyoderma, but no exfoliative toxins or similar toxins have been reported. PCR with degenerate primers targeted to the conserved regions in ETA, ETB, and ETD from S. aureus and SHETB from S. hyicus, and subsequent chromosome walking identified a novel gene, designated as exi (exfoliative toxin of pseudintermedius) in S. pseudintermedius. EXI had significant homologies with the exfoliative toxins (43-68% identity), particularly with ETB (67.1%), ETD (67.9%), and SHETB (65.1%). Phylogenetic analysis showed close relation between EXI and ETB with a bootstrap value of 80%. Neonatal mice injected with the crude proteins from the culture supernatant or recombinant EXI showed gross blisters and/or characteristic skin exfoliation. The prevalence of exi assessed by dot-blot hybridization was 23.3% (10/43) in S. pseudintermedius isolates from canine pyoderma. The EXI reported herein is the first exfoliative toxin identified in S. pseudintermedius.

Spliceosomal introns play a key role in eukaryotic genome evolution and protein diversity. A large Rab GTPase family has been identified in a unicellular eukaryote Trichomonas vaginalis. However, the characteristics of introns in Rab genes of T. vaginalis have not been investigated previously. In this study, we identified a 25-bp spliceosomal intron in the T. vaginalis Rab1a (TvRab1a) gene, the smallest intron in T. vaginalis to be characterized to date. This intron contains a canonical splice site at both 5' (GT) and 3' (AG) ends, and a putative branch-point sequence (TCTAAC) that matches the Trichomonad consensus sequence of ACTAAC except for the first nucleotide. The position and phase of the TvRab1a intron are evolutionarily conserved in Rab1 homologous genes across at least five eukaryotic supergroups, including Opisthokonta, Amoebozoa, Excavata, Chromalveolata, and Plantae. These results strongly suggest that the TvRab1a intron is likely to be an ancient spliceosomal intron, and it can therefore be used as a phylogenetic marker to evaluate particular eukaryotic groupings. Identification and characterization of the TvRabla intron may provide an insight into the evolution of the large Rab repertoire in T. vaginalis.

Staphylococcus intermedius isolates (n=106), including 44 dog isolates and 62 pigeon isolates, were examined for their susceptibility to ampicillin, cephalexin, erythromycin, gentamicin, kanamycin, lincomycin, norfloxacin, oxacillin, tetracycline, and vancomycin by standard disk-diffusion test. The frequencies of resistance to ampicillin, kanamycin, and tetracycline were significantly higher in dog isolates than pigeon isolates (95.5% vs. 0%, 31.8% vs. 0%, and 45.5% vs. 9.7%, respectively; P

Type 1 fimbriae of Escherichia coli mediate mannose-specific adhesion to host epithelial surfaces and consist of a major, antigenically variable pilin subunit, FimA, and a minor, structurally conserved adhesive subunit, FimH, located on the fimbrial tip. We have analysed the variability of fimA and fimH in strains of vaginal and other origin that belong to one of the most prominent clonal groups of extraintestinal pathogenic E. coli, comprised of O1:K1-, O2:K1- and O18:K1-based serotypes. Multiple locus sequence typing (MLST) of this group revealed that the strains have identical (at all but one nucleotide position) eight housekeeping loci around the genome and belong to the ST95 complex defined by the publicly available E. coli MLST database. Multiple highly diverse fimA alleles have been introduced into the ST95 clonal complex via horizontal transfer, at a frequency comparable to that of genes defining the major O- and H-antigens. However, no further significant FimA diversification has occurred via point mutation after the transfers. In contrast, while fimH alleles also move horizontally (along with the fimA loci), they acquire point amino acid replacements at a higher rate than either housekeeping genes or fimA. These FimH mutations enhance binding to monomannose receptors and bacterial tropism for human vaginal epithelium. A similar pattern of rapid within-clonal structural evolution of the adhesive, but not pilin, subunit is also seen, respectively, in papG and papA alleles of the di-galactose-specific P-fimbriae. Thus, while structurally diverse pilin subunits of E. coli fimbriae are under selective pressure for frequent horizontal transfer between clones, the adhesive subunits of extraintes-tinal E. coli are under strong positive selection (Dn/ Ds > 1 for fimH and papG) for functionally adaptive amino acid replacements.

Background Emergence of multidrug-resistant Neisseria gonorrhoeae resulting from new genetic mutations is a serious threat to controlling gonorrhea. Goal To determine 1) antimicrobial susceptibilities and the corresponding genetic mutations and 2) the role of MtrRCDE efflux system in gonococcal resistance to fluoroquinolones. Study design Antimicrobial susceptibility testing and sequence analysis of gyrA, parC, and mtrR loci of 131 N. gonorrhoeae isolates from Japan. Results The proportion of N. gonorrhoeae strains resistant and intermediate-resistant to antimicrobials was 25.2% and 48.9% for ciprofloxacin, 25.2% and 30.5% for ofloxacin, 12.2% and 53.4% for penicillin; and 17.6% and 51.1% for tetracycline, respectively. Strains were categorized into 22 mutation profiles, with GyrA-S91F/ParC-D86N/MtrR-G45D being the most predominant profile. The frequency of mutation in gyrA, parC, mtrR, and the mtrR promoter was 71%, 47.3%, 77.1%, and 23.7%, respectively. Seventy-one percent of strains carried mutations in both gyrA and mtrR. Conclusion This study reports simultaneous mutations in fluoroquinolone target enzymes and the MtrRCDE efflux system as a fluoroquinolone-resistant mechanism in N. gonorrhoeae.

Escherichia coli isolates (n = 2629) were collected between 1996 and 2000 from 2100 Thai children less than 12 years of age with acute diarrhoea. Enterotoxigenic (ETEC), enteroinvasive (EIEC), Shiga-toxin-producing (STEC), enteropathogenic (EPEC) and enteroaggregative (EAEC) E. coli were identified by their virulence marker profiles, as determined by multiplex PCR, and HeLa cell-adherence patterns. Serogroups of isolates were determined using 43 monovalent O antisera. Of 2629 isolates, 16.9 % were identified as diarrhoeagenic E. coli, and the mean isolation rates per year were 10.2 % for EAEC (range 8–12.5 %), 3.2 % for EPEC (0–8 %), 3.0 % for ETEC (2–5.4 %), 0.5 % for EIEC (0–1 %) and 0.04 % for STEC (0–0.1 %). The isolation rates of pathotypes from four different age groups (0–5 months, 6–11 months, 1–2 years and 2–12 years) in 905 children whose ages were recorded were respectively 19.3, 18.2, 9.1 and 8.1 % for EAEC, 3.1, 4.3, 1.7 and 2.2 % for EPEC and 2.6, 2.3, 1.3 and 5 % for ETEC. About 38 % of diarrhoeagenic E. coli, including 55.1, 66.7, 100, 45.9 and 29 %, respectively, of ETEC, EIEC, STEC, EPEC and EAEC, and 24 % of non-diarrhoeagenic E. coli were O-antigen typable. Only four serogroups (9.3 %) were restricted to single pathotypes, whereas 27 serogroups (62.8 %) were not restricted to any pathotype. This study shows that EAEC are the most prevalent diarrhoea-associated pathotype in Thai children.

This study involved 82 Salmonella enterica serovar Oranienburg isolates from patients with gastroenteritis and/or focal infections, healthy carriers, and cuttlefish chips which were epidemiologically linked to a major outbreak that had affected 1,505 people in Japan between 1998 and 1999. We concurrently investigated four different molecular subtyping methods using human salmonellosis-associated Salmonella serovars and their applicability in detection of serovar Oranienburg in an outbreak. Pulsed-field gel electrophoresis (PFGE), enterobacterial repetitive intergenic sequence PCR (ERIC2-PCR), or 16S/23S rRNA ribotyping provided a high degree of interserovar discrimination for most of the serovars, with PFGE being the most discriminatory. For intraserovar typing of serovar Oranienburg, ERIC2-PCR was found to be the most sensitive. Native plasmid profiling, however, revealed nine different subgroups among epidemiologically and genetically related outbreak strains. Using these methods, a link was confirmed between food (cuttlefish chips) and patients in the serovar Oranienburg outbreak. This study underscores the limitations of chromosome-based and plasmid-based typing methods.

Literature about healthcare-associated infection (HCAI) in China is scarce. A cross-sectional anonymous survey was conducted on 647 clinicians (199 physicians and 448 nurses) from six Shanghai hospitals (grades A–C) to investigate their cognizance, knowledge, attitude, self-reported practice, and risks regarding HCAI with emphasis on precautions. The mean overall score of HCAI knowledge was 40.89±11.4 (mean±SD; range, 13∼72) out of 100 for physicians and 43.48±9.9 (10∼70) for nurses. The respondents generally received high scores in hand hygiene, HCAI core concept, and healthcare worker safety but low scores in HCAI pathogen identification and isolation precautions. There were substantial variations in the knowledge scores of various demographic groups across individual hospitals and within hospital grades (ps

Isoform 2b of the plasma membrane calcium pump differs from the ubiquitous isoform 4b in the following: (a) higher basal activity in the absence of calmodulin; (b) higher affinity for calmodulin; and (c) higher affinity for Ca2+ in the presence of calmodulin [Elwess, Filoteo, Enyedi and Penniston (1997) J. Biol. Chem. 272, 17981–17986]. To investigate which parts of the molecule determine these kinetic differences, we made four chimaeric constructs in which portions of isoform 2b were grafted into isoform 4b: chimaera I contains only the C-terminal regulatory region of isoform 2b; chimaera II contains the N-terminal moiety of isoform 2b, including both cytoplasmic loops; chimaera III contains the sequence of isoform 2b starting from the N-terminus to after the end of the first (small) cytoplasmic loop; and chimaera IV contains only the second (large) cytoplasmic loop. Surprisingly, chimaera I showed low basal activity in the absence of calmodulin and low affinity for calmodulin, unlike isoform 2b. In contrast, the chimaera containing both loops showed high basal activity, and Ca2+ activation curves (both in the absence and in the presence of calmodulin) similar to those of isoform 2b. The rates of activation by calmodulin and of inactivation by calmodulin removal were measured, and the apparent Kd for calmodulin was calculated from the ratio between these rate constants. The order of affinity was: 2b = II>4b = IV>III = I. From these results it is clear that the construct that most closely resembles isoform 2b is chimaera II. This shows that, in order to obtain an enzyme with properties similar to those of isoform 2b, both cytoplasmic loops are needed.

Introduction: This study investigated the current state of attitudes, behaviors, and knowledge concerning sex and sexually transmitted infections (STIs) among Chinese university students. Methodology: A cross-sectional anonymous university intranet-based survey was given to students attending the Shantou University, Guangdong, China using a 28-item questionnaire. Results: Of 3425 website visitors, 1030 university students completed the survey, of which 80% were between 20 and 25 years of age, 76% considered pre-marital sex acceptable, 21% had had sexual intercourse, and 45% of sexually active students had engaged in oral sex, anal intercourse, or sex with strangers. Students had limited knowledge and awareness about common STIs, symptoms, and complications. Three percent of the sexually active students reported having had STIs and another 8% were not sure whether they had or not. Most students had misconceptions about transmission and prevention of STIs. The internet was the main information resource for 76% of students. Conclusions: Despite having more open attitudes and behaviors towards sex, students’ STI knowledge and awareness of STI risks was considerably limited, raising concerns about a likely rise in STI incidence. Prior knowledge of STIs had no significant influence. Targeted educational measures such as online education and counseling via Chinese websites and social media, and the provision of safer sex and STI-related information by health experts to university students are suggested.

Clostridium perfringens KZ1340, previously classified as Clostridium plagarum, is an isolate from Antarctic soil, and was identified as an alpha-, theta-, and kappa-toxin non-producing variant. On Southern hybridization, the variant was found to be defective in the pfoA (theta-toxin) gene, but the plc (alpha-toxin) and colA (kappa-toxin) genes were present on the same EcoRI fragment as in the standard strain, NCTC8237. Northern analysis revealed that mature plc mRNA was transcribed in KZ1340 though less efficiently than in NCTC8237, while no mature colA mRNA was present in KZ1340. After transformation of the pfoA and plc genes into the KZ1340 via shuttle vector, pJIR418, the pfoA gene was successfully expressed but the plc gene was not efficiently expressed, suggesting that in KZ1340 there is negative regulation of plc gene expression. Toxin-deficient C. perfringens KZ1340 might be a suitable host for expression analysis of the pfoA gene and other clostridial virulence genes, if expressed efficiently, because it produces a small amount of extracellular toxins.

Staphylococcus intermedius isolates from dogs ( n = 44) and pigeons ( n = 62) were categorized into 12 types by intergenic ribosomal DNA spacer polymorphism analysis. All isolates from pigeons were lukS positive and all isolates from dogs were lukS and lukF positive by dot blot analysis. The mean leukotoxicity titer for dog isolates was at least 129-fold higher than that for pigeon isolates.

Introduction: Health-care associated infections (HCAIs) occur worldwide and affect both patients and health-care workers (HCWs), including medical students. This study aimed to investigate HCAI risks associated with clinical medical students attending Shantou University Medical College (SUMC) and the effectiveness of their learning resources. Methodology: Four cohorts (n = 272) of medical students participated in a questionnaire-based survey was done on (year 5 in the 5-year program and years 5 to 7 in the 7-year program) undergoing internship training in 14 teaching hospitals in Guangdong, China. Results: The mean overall score of the students was 52.54 ± 0.45 (mean ± SE). Students received fairly good scores in hand hygiene (77.57 ± 0.77) and HCAI source (63.16 ± 1.18); relatively weak scores in the isolation precautions (44.59 ± 0.55), HCW safety (45.59 ± 0.86), and personal protective equipment (57.64 ± 0.60); and the weakest scores in HCA-pathogen identification (27.44 ± 0.81). The year of education (r = 0.089, P = 0.144, n = 272) or internship placement (r = 0.077, P = 0.206, n = 272) had no significant influence on their level of knowledge. Conclusions: This study demonstrates that medical students at SUMC have limited knowledge and practice regarding HCAI due to substantial deficiencies in their learning resources. Review of medical curricula, improvement in preclinical and clinical training, and surveillance and monitoring of practicing HCWs are urgently needed to minimize risk of HCAIs in patients and HCWs.

The perfringolysin O (theta-toxin) gene (pfoA) of Clostridium perfringens was cloned into an Escherichia coli-C. perfringens shuttle vector, and the pfoA gene was expressed in mutants of C. perfringens 13 which lacked the production of perfringolysin O. One group (SI117) could express the pfoA gene, and the other (SI112) could not. A mutation in the regulatory system for pfoA gene expression was suspected in SI112. A chromosomal DNA library constructed from strain 13 was transformed into strain SI112 to identify the regulatory gene(s) for the pfoA gene. Five strains of 10,000 transformants restored perfringolysin O production. All contained a 2.5-kb DNA fragment. This fragment activated the transcription of the pfoA gene and also restored the production of collagenase (kappa-toxin) and hemagglutinin in strain SI112. Deletion analysis showed that a 1.25-kb region was sufficient for the trans activity, and sequence analysis disclosed that open reading frame 2 (ORF2) was located in this region. A homology search for the deduced amino acid sequence revealed that ORF2 was homologous to a response regulator in a two-component signal transduction system. ORF2 was designated virR, and it is suggested that the virR gene plays an important role in the pathogenicity of C. perfringens.

Staphylococcus hyicus isolates (n=207), including 150 exfolitative toxigenic and 57 non-toxigenic strains, were examined for their susceptibility to 13 antimicrobial agents by using the dehydrated 96-well MIC panel system. The frequency of their resistance to penicillin and ampicillin was 76.8% (159/207), followed by erythromycin (56%, 116/207), trimethoprim-sulfamethoxazole (28.5%, 59/207), chloramphenicol (24.2%, 50/207), kanamycin (19.8%, 41/207), and doxycycline (1.4%, 3/207). Resistance to chloramphenicol and trimethoprim-sulfamethoxazole was significantly higher in toxigenic strains than non-toxigenic strains (p

We investigated the carriage of Staphylococcus hyicus and their exfoliative toxin genes (exhA, exhB, exhC, exhD, and shetb) among 424 pigs from 38 Japanese pig farms by PCR and characterized the isolates by 16S-23S intergenic spacer region polymorphism analysis. S. hyicus (n=207) were isolated from 17.9% of pigs and 72.5% of them were toxigenic. The isolation rate of toxigenic S. hyicus was four times higher in the pigs with exudative epidermitis than the healthy pigs (87.6% versus 19.6%; p

Background Staphylococcus intermedius has been isolated from healthy dogs and pigeons as well as diseased dogs. Similar to Staphylococcus aureus, S. intermedius is known to carry many virulence factors but most of these factors remain to be studied. In this study, we examined 106 S. intermedius isolates (44 dog isolates and 62 pigeon isolates) for their hemolytic activity, biofilm formation, protease activity, and clumping factor and protein A production. Results Forty-three dog isolates (97.7%) and all pigeon isolates were hemolytic on sheep RBCs with a mean hemolytic titer of 336.7 and 47.32, respectively, whereas 43 dog isolates (97.7%) and 11 pigeon isolates (17.7%) exhibited a significant difference in their hemolytic activity on rabbit RBCs with a mean hemolytic titer of 11.04 and 3.76, respectively (p < 0.0005). The mean biofilm formation activity for dog isolates was 0.49, which was significantly higher than that (0.33) for pigeon isolates (p < 0.0005). Twenty-four dog isolates (54.5%) and 11 pigeon isolates (17.7%) were protease positive. Twenty-four dog isolates (54.5%) were clumping factor- and protein A- positive. Conclusion S. intermedius strains carrying the virulence factors examined in this study were more prevalent in dogs than pigeons.

Aims: To determine the prevalence of enterotoxin-producing Staphylococcus intermedius in dogs and pigeons. Methods and Results: A total of 106 S. intermedius isolates from 44 dogs and 62 pigeons were tested for the production of enterotoxins A, B, C and D by reverse passive latex agglutination (RPLA) and for sec-canine by PCR. Only one isolate from dog was positive for SEC and sec-canine. Screening of sec-canine-negative strains by nested PCR led to the identification of a novel enterotoxin-related gene, se-int. SE-int showed a significant homology (59–61% identity) with SEC and (56·6% identity) SEB. All 44 isolates from dogs and five isolates (8·1%) from pigeons were se-int positive. Conclusions: While S. intermedius was isolated more frequently from pigeons than from dogs, se-int was more prevalent among the S. intermedius isolates from dogs, compared with the pigeon isolates. Significance and Impact of the Study: Further characterization of the se-int-positive S. intermedius strains should clarify their pathogenic potential including enterotoxigenicity and zoonotic transmissibility to human beings.

OBJECTIVE: To develop a polymerase chain reaction (PCR)-based diagnostic method for bacterial vaginosis using bacterial vaginosis-associated anaerobes. METHODS: A multiple PCR assay was developed using primers specific to 16S ribosomal deoxyribonucleic acid (DNA) ( Mobiluncus mulieris and Mobiluncus curtisii ), nanH ( Bacteroides fragilis ), and an internal spacer region of ribosomal DNA ( Gardnerella vaginalis ). The vaginal swabs from pregnant and nonpregnant women were examined by Gram stain-based Nugent scoring system. One hundred seventy-two samples of 853 Gram stain-interpretable samples were randomly selected and subjected to multiplex PCR assay. RESULTS: The sensitivity of the PCR assay ranged from 10 3 to 10 4 colony-forming units per vaginal swab. The prevalence of the bacterial vaginosis, intermediate, and normal categories was found by Nugent scoring system to be 21.6% (184/853), 26.0% (222/853), and 52.4% (447/853), respectively. By the multiplex PCR-based diagnostic method, 20.3% (35/172) of the samples were identified as bacterial vaginosis. The diagnostic sensitivity, specificity, positive predictive value, and negative predictive value of multiplex PCR in comparison with Gram stain examination were 78.4% (95% confidence interval [CI] 65.1%, 91.6%), 95.6% (95% CI 92.1%, 99.0%), 82.9% (95% CI 70.4%, 95.4%), and 94.2% (95% CI 90.3%, 98.1%), respectively. CONCLUSION: This multiplex PCR can be used as a diagnostic or screening test for bacterial vaginosis.

Characteristics of Escherichia coli residing in the vagina and their role in extraintestinal infections are largely unknown. In this study, 88 vaginal E. coli (VEC) isolates from Japanese women were characterized by extraintestinal virulence factor (VF) profiling, O:H serotyping and phylogenetic analysis. The prevalence of papC, hlyA, cnfI, PAI, ibeA and K1 antigen among the VEC strains were 45, 22, 19, 78, 32 and 44%, respectively. Phylogenetic analysis identified 76, 16 and 8% of the VEC strains in groups B2, D and A, respectively. The VEC strains were distributed into 31 serotypes, including 8 common serotypes (O1:K1:H1, O1:K1:H7, O2:K1:H7, O4:H5, O6:H1, O18ac:K1:H7, O25:H1 and O75:HNM) that were identified in three or more isolates. Comparative analysis with 61 stool isolates from healthy Japanese men and women, and with data from previous studies, revealed that, although some geographical specificities do exist, the VEC strains shared common VF profiles, O:K:H serotypes and phylogeny with uropathogenic E. coli and E. coli of neonatal septicaemia and meningitis. This study provides additional evidence for a link among extraintestinal E. coli, supporting the concept that the VEC are a reservoir along the ‘faecal–vaginal–urinary/neonatal’ course of transmission in the extraintestinal E. coli infections.

To determine virulence-related genes in uropathogenic Escherichia coli (UPEC) showing invasiveness to T-24 bladder cancer cells, genomic subtractive hybridization was performed between a highly invasive and a less invasive strain. Forty-nine DNA fragments were isolated from the invasive strain. One of them showed homology with Salmonella invA gene. By chromosomal walking of the strain, a type III secretion system that has been described in E. coli O157:H7 was identified on the genome of the invasive strains. Three strains out of 100 UPEC isolates had a type III secretion system inserted at 64 min of the chromosome, corresponding to E. coli K-12 MG1655. This finding suggested that the type III secretion system could play a part in uropathogenicity of UPEC.

Fimbrial (type 1, P, and S) and afimbrial adhesins, the unique virulence traits of uropathogenic Escherichia coli (UPEC), are well recognized for their role in the initial step of uropathogenesis. In this study, we investigated whether these adhesins are dispensable for UPEC in adherence and invasion of uroepithelial cells by using E. coli isolates (n=40) from cystitis patients and T-24 cells, the bladder carcinoma cell line. We found all isolates adherent to T-24 cells within 15 min of infection. In invasion assay, all isolates could invade T-24 cells to a variable degree; 22.5% of them were found highly invasive. About 33% of isolates that do not have any recognized adhesins were as invasive as other isolates. The amplitude of invasiveness was also independent of the adhesins. In conclusion, this study demonstrates that type 1 fimbriae, P fimbriae, S fimbriae, and afimbrial adhesin I are not required for UPEC to adhere to and invade uroepithelial cells.

The genomic structure of the pfoA-colA region in six theta-toxin-deficient strains of Clostridium perfringens was examined by Southern hybridization using the pfoR, pfoA, pbg, arcABDC and colA genes, encoding regulator for pfoA, theta-toxin, beta-galactosidase, arginine metabolism enzymes and kappa-toxin, respectively, as gene probes. It is suggested that the productivity of theta-toxin in these strains is diverse because of the multiple genetic backgrounds including single deletion of pfoA, large deletion of the pfoA-colA region and the putative point mutations.

The 3'-flanking region of the perfringolysin O (theta-toxin) gene (pfoA) of Clostridium perfringens was analyzed by chromosome walking. A total of 5,363 bp of the downstream region of the pfoA gene was sequenced and four open reading frames were found. ORF54 and ORF80 were found to be homologous to genes coding for membrane-bound transporter proteins of other bacteria and the beta-galactosidase gene (bgaB) of Bacillus stearothermophilus, respectively. ORF80 was named the pbg gene. Clones which showed beta-galactosidase activities were selected from a lambda FIXII genomic library of C. perfringens by blue plaque screening using X-Gal as a substrate. Four clones whose plaques showed blue appearances were obtained. Two of the four clones hybridized with the pbg probe but the others did not, indicating that there are two distinct beta-galactosidase genes in C. perfringens. The pbg gene was subcloned into pBR322 and was successfully expressed in Escherichia coli, suggesting that the pbg gene codes for a beta-galactosidase of C. perfringens.

Background Acute respiratory infections (ARIs) are common in children and mostly caused by viruses, but the significance of the detection of multiple viruses in ARIs is unclear. This study investigated 14 respiratory viruses in ARIs among children and associated meteorological factors in Shantou, southern China. Methods Paired nasal/throat-flocked swabs collected from 1,074 children with ARIs, who visited outpatient walk-in clinics in a tertiary hospital between December 2010 and November 2011, were examined for fourteen respiratory viruses - influenza viruses (FluA, FluB), respiratory syncytial viruses (RSV A and B), human coronaviruses (hCoV: 229E, OC43, HKU1, NL63), human metapneumoviruses (hMPV A and B), parainfluenza viruses (PIV1-4), human rhinoviruses (HRV A, B, C), enteroviruses (EV), adenoviruses (ADV), human bocavirus (hBoV), and human parechoviruses (hPeV) - by multiplex real-time PCR. Results We identified at least one virus in 82.3% (884/1,074) and multiple viruses in 38.6% (415/1,074) of patients. EV and HRV were the most frequently detected single viruses (42.3%, 374/884 and 39.9%, 353/884 respectively) and co-detected pair (23.1%, 96/415). Overlapping seasonal trends of viruses were recorded over the year, with dual peaks for EV and single peaks for the others. By logistic regression analysis, EV was positively associated with the average temperature and humidity, hCoV, and PIV4, but negatively with HRV, PIV3, and hBoV. HRV was inversely associated with EV and PIV3. Conclusions This study reports high viral detection and co-detection rates in pediatric ARI cases mainly due to EV and HRV. Many viruses circulated throughout the year with similar seasonal trends in association with temperature, humidity, and wind velocity. Statistically significant associations were present among the viruses. Understanding the polyviral etiology and viral interactions in the cases with multiple viruses warrants further studies. Electronic supplementary material The online version of this article (doi:10.1186/s12879-015-0863-6) contains supplementary material, which is available to authorized users.

Extracellular toxin production in Clostridium perfringens is positively regulated by the two-component regulatory genes virR and virS. Northern (RNA) blots carried out with RNA preparations from the wild-type strain 13 and the isogenic virR and virS mutants TS133 and JIR4000 showed that the virR and virS genes composed an operon and were transcribed as a single 2.1-kb mRNA molecule. Primer extension analysis led to the identification of two promoters upstream of virR. Hybridization analysis of the mutants and their complemented derivatives showed that the virR/virS system positively regulated the production of alpha-toxin (or phospholipase C, theta-toxin (perfringolysin O), and kappa-toxin (collagenase) at the transcriptional level. However, the modes of regulation of these genes were shown to differ. The theta-toxin structural gene, pfoA, had both a major and a very minor promoter, with the major promoter being virR/virS dependent. The colA gene, which encodes the kappa-toxin, had two major promoters, only one of which was virR/virS-dependent. In contrast, the alpha-toxin structural gene, p1c, had only one promoter, which was shown to be partially regulated by the virR and virS genes. Comparative analysis of the virR/virS-dependent promoters did not reveal any common sequence motifs that could represent VirR-binding sites. It was concluded that either the virR/virS system modulates its effects via secondary regulatory genes that are specific for each toxin structural gene or the VirR protein does not have a single consensus binding sequence.