OBJECTIVETo investigate the application of pulsed-field gel electrophoresis (PFGE) in food-borne outbreak.

METHODSPathogens were isolated and further characteristics identified by traditional methods. The strains isolated were carried out with molecular typing with using PFGE. PFGE was performed by Laboratory Directions for molecular subtyping of Salmonella by PFGE (CDC, USA) and the results of PFGE were analyzed by BioNumerics soft.

RESULTSTotally 14 Salmonella serotype Muenchen strains were isolated from 19 patients, 3 of 9 suspicious foods were positive for S. muenchen and 7 strains were isolated from 18 cooks. The biochemistry characterization and antimicrobial susceptibility of all the strains isolated were the same. 23 S. muenchen isolates were all shown indistinguishable by PFGE.

CONCLUSIONPFGE should play a key role in identifying the outbreak-associated isolates and distinguishing them from unrelated sporadic isolates. It might also demonstrate that the genetic fingerprints of serotype Muenchen isolates derived from patients were indistinguishable from those derived from drinks. PFGE might provide precise information on bacterial food-borne pathogens, promptly identify the source of infection, and effectively prevent from spreading. It should be one of the early warning method on controlling outbreak of the food-borne disease.

China ; epidemiology ; Disease Outbreaks ; Electrophoresis, Gel, Pulsed-Field ; methods ; Humans ; Microbial Sensitivity Tests ; Salmonella Food Poisoning ; epidemiology ; microbiology ; Salmonella enterica ; classification ; isolation & purification ; Serotyping

Objective To evaluate the development of the sphincter muscle complex(SMC)and defecation function in pediatric patients with congenital anorectal malformations(ARM).Methods A total of 64 children underwent MRI,among whom 39 were patients with ARM,and the others were patients without ARM undergoing MRI because of other dieases.The dimensions of the SMC in different planes were evaluated with different sequences and coils.The relationship between the SMC development and the defecation function was investigated.Results In control group,the absolute value of SMC width was (3.63?0.22)mm,which had a high correlation with age(r=0.998,P0.05).The SMCs in intermediate ARM patients[muscle index(MI)=0.47?0.05]and low ARM patients(MI=0.49? 0.05)were well developed.The SMCs in a portion of patients with high ARM(MI=0.28?0.06)were poorly developed,when MI≤0.18,anorectal contraction pressurewas significantly lower(t=3.55, P0.18[(0.85?0.20)vs(2.24?1.02)kPa].The length of anal canal with high-pressure[(10.88?3.64)vs(20.26?4.34)mm]was shorter(t=5.18,P0.18,the anorectal angle was less than 90 degrees,and normal continent function was found in 21 of 23 cases(91%).Conclusion MRI can be employed to evaluate the development of SMC in patients with ARM,MI was an objective criteria to evaluate the development of SMC.When MI≤0.18, maldevelopment of SMC will be highly suspected.

BACKGROUNDAnatomic and electrophysiological studies have revealed that the neurons located in the media vestibular nuclei (MVN) receive most of the sensory vestibular input coming from the ipsilateral labyrinth and the responses of MVN neurons to caloric stimulation directly reflect changes in primary vestibular afferent activity. The aim of this study was to clarify the intrinsic characteristics of serotonin (5-hydroxytryptamine, 5-HT) release in the MVN during the period of vertigo induced by caloric stimulation.

METHODSWe used an in vivo microdialysis technique to examine the effects of caloric stimulation on the serotoninergic system in MVN. Twenty four guinea pigs were randomly divided into the groups of irrigation of the ear canal with hot water (n = 6), ice water (n = 6) and 37 degrees C water (n = 4), and the groups of irrigation of the auricle with hot water (n = 4) and ice water (n = 4), according to different caloric vestibular stimulation. We examined the animal's caloric nystagmus with a two-channel electronystagmographic recorder (ENG), and meanwhile examine serotonin (5-hydroxytryptamine, 5-HT) level in the MVN with microdialysis technique after caloric stimulation.

RESULTSIn the caloric test the hot water (44 degrees C) irrigation of the right external auditory canal induced horizontal nystagmus towards the right side lasting about 60 seconds and the ice water irrigation of the right external auditory canal induced it towards the left side lasting for about 90 seconds. No nystagmus was induced by 37 degrees C water irrigation of the external ear canal. Therefore, it was used as a negative control stimulation to the middle ear. The MVN 5-HT levels significantly increased in the first 5-minute collecting interval and increased to 254% and 189% of the control group in the second collecting interval in response to caloric vestibular stimulation with ice water and hot water respectively. The serotonin release was not distinctly changed by the irrigation of the auricle with ice water or hot water.

CONCLUSIONSNeither somato-sensory stimulation of the middle ear nor nonspecific cold or hot stress affects the serotonin release. The rise of 5-HT in MVN may be involved in the mechanism of vertigo induced by caloric stimulation.

Animals ; Caloric Tests ; Guinea Pigs ; Microdialysis ; Serotonin ; secretion ; Vertigo ; etiology ; Vestibular Nuclei ; pathology

The purpose of this study was to investigate the effects of chloroquine diphosphate on the proliferation and apoptosis of human leukemic K562 cells, and to elucidate its possible mechanism of activity. The inhibitory effect of chloroquine diphosphate with different concentrations on K562 cell proliferation was detected by MTT method. Apoptosis was measured by flow cytometry (FCM); morphological analysis of apoptosis was performed after staining with propidium iodide (PI) under fluorescence microscope; cell apoptosis was assessed by the DNA ladder shown agarose gel electrophoresis. After treatment with chloroquine diphosphate, K562 cells were stained by Rhodamine 123 to detect changes in mitochondrial transmembrane potential (DeltaPsim) by FCM. The results showed that the cell viability decreased in dose-dependent manner, following chloroquine diphosphate treatment at different concentrations (1.5625, 3.125, 6.25, 12.5, 25, 50 and 100 micromol/L) for 24, 48 and 72 hours. By FCM analysis, the significant increases of sub-G(1) were observed. DNA ladder was detected and apoptotic nuclei were observed. DeltaPsim decreased in K562 cells after chloroquine diphosphate treatment. It is concluded that the chloroquine diphosphate can inhibit the proliferation of K562 cells and induce cell apoptosis, which may relate to down-regulation of mitochondrial transmembrane potential (DeltaPsim).
Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Cell Proliferation ; drug effects ; Chloroquine ; analogs & derivatives ; pharmacology ; Dose-Response Relationship, Drug ; Down-Regulation ; drug effects ; Humans ; K562 Cells ; Membrane Potentials ; drug effects ; Mitochondria ; drug effects

OBJECTIVETo explore the morphometric abnormalities of brain gray matter (GM) in patients with chronic low back pain (CLBP).

METHODSThirty patients with CLBP and 30 healthy individuals were enrolled and examined with a 3.0 T magnetic resonance (MR) scanner. High-resolution T1 structural MR data were acquired and data analysis was performed using voxel-based morphometry (VBM) in FMRIB Software Library. The morphological differences were compared between the two groups.

RESULTSs Compared with the healthy control subjects, patients with CLBP showed decreased GM volumes in several brain cortical areas including the bilateral superior frontal gyrus, right frontal pole, left insular cortex, left middle and left inferior temporal gyrus (P<0.05, after TFCE correction). Increased GM volumes were found in the patients in the subcortical structures including the left thalamus, bilateral putamen, bilateral nucleus accumben and right caudate nucleus (P<0.05, after TFCE correction).

CONCLUSIONPatients with CLBP have different patterns of GM abnormalities in different brain regions, characterized by reduced GM volume in cerebral cortical regions and increased GM volume in the subcortical nuclei. Such changes might be associated with the maladaptation of the brain in chronic pain state.

Cerebral Cortex ; Frontal Lobe ; Gray Matter ; diagnostic imaging ; pathology ; Humans ; Low Back Pain ; physiopathology ; Magnetic Resonance Imaging ; Temporal Lobe ; Thalamus

Objective To understand the status and demands of specialized training among neurological nurses in Chongqing city and provide evidence for formulating neurological specialized training standard courses.Methods Totals of 178 neurological nurses of 21 hospitals in Chongqing city were investigated by self-designed questionnaire.Results The rate of never accepted neurological specialized training among them was 86.5％ before working and 61.2％ after working.All of them never received standard training and 94.4％ nurses were willing to received standard specialized training.The top three willing training contents were: specialized skills of neurology department ( 153 nurses),first aid skills ( 152 nurses),specialized knowledge ( 147 nurses ).Compared the demands of neurological nurses with different conditions for comprehensive ability training,except professional title,education backgrounds had statistical difference( F =5.569,7.405 ;P ＜0.01 ),the rest terms had no statistical difference( P ＞0.05).Compared the demands of neurological nurses with different conditions for specialized skill training,except professional titles and education background had statistical difference( F =4.646,7.434;P＜0.01),the rest terms had no statistical difference(P ＞0.05).Contusions Neurological nurses are lack of specialized training and the demand of the specialized training is higher,so it is imperative to develop the specialized training for neurological nurses.

Objective To assess the safety, immunogenicity and efficacy of group A and C meningococcal polysaccharide vaccine (A/C MPV) in response to an outbreak of group C meningococcal disease. Methods A vaccination campaign with A/C MPV was prompted 6 weeks after the use of group A MPV in Laibin city, Guangxi, where an outbreak of group C meningococcal meningitis occurred in 2002.Vaccinees were observed for local and systemic reactions after the vaccination and followed up for the meningococcal disease for 5 years. Blood samples were collected from 71 people in the epidemic and 43 in the non-epidemic areas before and 1 month after the vaccination and examined by ELISA to detect IgG antibodies to group A and C polysaccharides. Results The vaccination coverage was 97%. No significant adverse reactions were observed. The positive rates of group C antibodies after vaccination was between 97.67% and 100% among the populations in the epidemic and non-epidemic areas, as well as among those negative and positive for group C antibodies prior to the vaccination.The geometric mean anti-C concentrations ranged 30.81 μg/ml to 37.44 μg/ml, showing no significant difference between groups. The incidence rate of meningococcal disease in students with timely immunization (218.58/100 000) dropped by 69.02% , when compared to that in those with delayed immunization (705.72/100 000). No clinical cases were identified during the follow-up period of 15 760 person-years. Conclusion The vaccination campaign with the Chinese group A/C MPV seemed successful in controlling the group C meningococcal outbreak.The vaccine was shown to be safe even administered after the group A vaccine only 6 weeks apart. It could induce high levels of antibodies in vulnerable population and significantly increase antibody levels in seropositive individuals, thus providing a protection of at least 5 years.

Objective To investigate the infection status and changing trend of hepatitis C virus(HCV)infection in hospitalized patients in medical institutions,and provide reference for formulating HCV infection prevention and control strategies.Methods HCV infection surveillance results from cross-sectional survey data reported to China Healthcare-associated Infection(HAI)Surveillance System in 2020 were summarized and analyzed,HCV positive was serum anti-HCV positive or HCV RNA positive,survey result was compared with the survey results from 2003.Results In 2020,1 071 368 inpatients in 1 573 hospitals were surveyed,738 535 of whom underwent HCV test,4 014 patients were infected with HCV,with a detection rate of 68.93％and a HCV positive rate of 0.54％.The positive rate of HCV in male and female patients were 0.60％and 0.48％,respectively,with a statistically sig-nificant difference(x2=47.18,P＜0.001).The HCV positive rate in the 50-＜60 age group was the highest(0.76％),followed by the 40-＜50 age group(0.71％).Difference among all age groups was statistically signifi-cant(x2=696.74,P＜0.001).In 2003,91 113 inpatients were surveyed.35 145 of whom underwent HCV test,resulting in a detection rate of 38.57％;775 patients were infected with HCV,with a positive rate of 2.21％.In 2020,HCV positive rates in hospitals of different scales were 0.46％-0.63％,with the highest in hospital with bed numbers ranging 600-899.Patients'HCV positive rates in hospitals of different scales was statistically signifi-cant(X2=35.34,P＜0.001).In 2020,12 provinces/municipalities had over 10 000 patients underwent HCV-rela-ted test,and HCV positive rates ranged 0.19％-0.81％,with the highest rate from Hainan Province.HCV posi-tive rates in different departments were 0.06％-0.82％,with the lowest positive rate in the department of pedia-trics and the highest in the department of internal medicine.In 2003 and 2020,HCV positive rates in the depart-ment of infectious diseases were the highest,being 7.95％and 3.48％,respectively.Followed by departments of orthopedics(7.72％),gastroenterology(3.77％),nephrology(3.57％)and general intensive care unit(ICU,3.10％)in 2003,as well as departments of gastroenterology(1.35％),nephrology(1.18％),endocrinology(0.91％),and general intensive care unit(ICU,0.79％)in 2020.Conclusion Compared with 2003,HCV positive rate decreased significantly in 2020.HCV infected patients were mainly from the department of infectious diseases,followed by departments of gastroenterology,nephrology and general ICU.HCV infection positive rate varies with gender,age,and region.

Objective To analyze the distribution and antimicrobial resistance profile of clinical bacterial strains isolated from blood culture in China.Methods Clinical bacterial strains isolated from blood culture from participating hospitals of Blood Bacterial Resistance Investigation Collaborative System (BRICS) during January 2014 to December 2015 were collected.Antibiotic susceptibility tests were conducted with agar dilution or broth dilution methods as recommended by US Clinical and Laboratory Standards Institute(CLSI)2018.The data were analyzed with Whonet 5.6 software.Results During the study period,4 801 clinical bacterial isolates were collected from 26 hospitals,of which 1 798 (37.5％) were Gram-positive bacteria and 3 003 (62.5％) were gram-negative bacteria.The top 10 isolates were Escherichia coli (33.8％),coagulase-negative Staphylococcus (19.0％),Klebsiella pneumoniae (11.9％),Staphylococcus aureus (10.1％),Acinetobacter baumannii (4.0％),Pseudomonas aeruginosa (3.8％),Streptococcus (3.0％),Enterobacter sulcus (2.9％),Enterococcus faecium (2.8％) and Enterococcus faecalis (1.8％).Methicillin-resistant Staphylococcus aureus (MRSA) and methicillinresistant coagulase-negative Staphylococcus (MRCNS) accounted for 33.9％ (165/487) and 56.9％ (520/913) of Staphylococcus aureus and coagulase-negative Staphylococcus respectively.No vancomycinresistant Staphylococcus was detected.The resistance rate of Enterococcus faecium to vancomycin was 0.7％ (1/135),and no vancomycin-resistant Enterococcus faecaliss was detected.The positive rates of extendedspectrum β-1actamases(ESBLs)-producing Escherichia coli,Klebsiella pneumoniae and Proteus were 56.9％ (923/1 621),30.1％ (172/572) and 29.2％ (7/24),respectively.The positive rates of carbapenemresistant Escherichia coli,Klebsiella pneumoniae,Enterobacter,Salmonella and Citrobacter were 1.2％ (20/1 621),7.2％ (41/572),4.3％ (6/141),1.5％ (1/67) and 2.9％ (1/34),respectively.The resistance rates of Acinetobacter baumannii to polymyxin and tegacycline were 2.6％ (5/190) and 8.9％ (17/190)respectively,and that of Pseudomonas aeruginosa to polymyxin and fosfomycin were 1.1％ (2/183)and 0.6％ (1/183),respectively.Conclusions The surveillance results from 2014 to 2015 show that the main pathogens of blood stream infection in China are Gram-negative bacteria,while Escherichia coli is the most common pathogen,the detection rate of MRSA is lower than other surveillance data in the same period in China;carbapenem-resistant Klebsiella pneumoniae and Escherichia coli are at a low level as shown in this surveillance.

Objective:To investigate the distribution and antimicrobial resistance profile of clinical bacteria isolated from blood culture in China.Methods:The clinical bacterial strains isolated from blood culture from member hospitals of Blood Bacterial Resistant Investigation Collaborative System (BRICS) were collected during January 2018 to December 2019. Antibiotic susceptibility tests were conducted with agar dilution or broth dilution methods recommended by US Clinical and Laboratory Standards Institute (CLSI). WHONET 5.6 was used to analyze data.Results:During the study period, 14 778 bacterial strains were collected from 50 hospitals, of which 4 117 (27.9%) were Gram-positive bacteria and 10 661(72.1%) were Gram-negative bacteria. The top 10 bacterial species were Escherichia coli (37.2%), Klebsiella pneumoniae (17.0%), Staphylococcus aureus (9.7%), coagulase-negative Staphylococci (8.7%), Pseudomonas aeruginosa (3.7%), Enterococcus faecium (3.4%), Acinetobacter baumannii(3.4%), Enterobacter cloacae (2.9%), Streptococci(2.8%) and Enterococcus faecalis (2.3%). The the prevalence of methicillin-resistant S. aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus were 27.4% (394/1 438) and 70.4% (905/1 285), respectively. No glycopeptide-resistant Staphylococcus was detected. More than 95% of S. aureus were sensitive to amikacin, rifampicin and SMZco. The resistance rate of E. faecium to vancomycin was 0.4% (2/504), and no vancomycin-resistant E. faecalis was detected. The ESBLs-producing rates in no carbapenem-resistance E. coli, carbapenem sensitive K. pneumoniae and Proteus were 50.4% (2 731/5 415), 24.6% (493/2001) and 35.2% (31/88), respectively. The prevalence of carbapenem-resistance in E. coli and K. pneumoniae were 1.5% (85/5 500), 20.6% (518/2 519), respectively. 8.3% (27/325) of carbapenem-resistance K. pneumoniae was resistant to ceftazidime/avibactam combination. The resistance rates of A. baumannii to polymyxin and tigecycline were 2.8% (14/501) and 3.4% (17/501) respectively, and that of P. aeruginosa to carbapenem were 18.9% (103/546). Conclusions:The surveillance results from 2018 to 2019 showed that the main pathogens of bloodstream infection in China were gram-negative bacteria, while E. coli was the most common pathogen, and ESBLs-producing strains were in majority; the MRSA incidence is getting lower in China; carbapenem-resistant E. coli keeps at a low level, while carbapenem-resistant K. pneumoniae is on the rise obviously.