Prevalence and Characterization of Cronobacter sakazakii in Retail Milk-Based Infant and Baby Foods in Shaanxi, China.

Cronobacter sakazakii (formerly Enterobacter sakazakii) is an opportunistic pathogen that causes meningitis, sepsis, and necrotizing enterocolitis in neonates and infants through consumption of contaminated milk-based foods. In this study, the prevalence of C. sakazakii in 705 retail milk-based infant and baby food samples was investigated in 12 cities in Shaanxi, China, in 2010 and 2012. One hundred and nineteen samples (16.9%) were C. sakazakii positive. The isolates were further characterized for antimicrobial susceptibility to 14 antibiotics, pulsed-field gel electrophoresis profiles, and presence of the virulence genes. Samples of brand W, Y, A, and G in 2010 and 2012 were C. sakazakii positive. All isolates recovered in 2010 and 2012 were susceptible to levofloxacin and cefoperazone. In 2012, no isolate was resistant to gentamicin, cefoxitin, chloramphenicol, gatifloxacin, ciprofloxacin, and ceftriaxone. Antibiotic resistance of the isolates was most commonly found to rifampicin, amoxicillin-clavulanic acid, streptomycin, tetracycline, and ampicillin in both 2010 and 2012, except to trimethoprim/sulfamethoxazole in 2012. Pulsed-field gel electrophoresis profiles indicated that C. sakazakii isolates were genotypically diverse, although these isolates were prevalent in infant and baby foods with the same brand. A total of 34 virulence gene profiles of the C. sakazakii isolates in 2010 and 2012 were detected. Isolates that co-carried hly-ompX-eitCBAD-iucABCD/iutA genes in 2012 were significantly (p < 0.05) more prevalent than those in 2010. The results added new epidemiological evidence for the widespread occurrence of C. sakazakii in retail milk-based infant and baby foods and this should be an indicator of potential health risk for consumers.

The SNAI1 3'UTR functions as a sponge for multiple migration-/invasion-related microRNAs.

Accumulating evidence has indicated a large-scale regulatory network generated by 3'untranslated regions (3'UTRs) in cancer. The 3'UTRs act not only in cis but, most likely even more importantly, as trans regulators of gene expression, consequently leading to phenotypic alterations. Here, we found that ectopic expression of SNAI1 3'UTR induced migration and invasion of ovarian cancer cell line RMUG-L without significantly affecting cell viability. Additionally, SNAI1 3'UTR overexpression regulated key epithelial-to-mesenchymal transition (EMT) markers, including SNAI1, Vimentin, and E-cadherin, and functioned as a sponge for multiple migration-/invasion-related microRNAs (miRNAs) in RMUG-L cells. These findings revealed the noncoding function of SNAI1 for the first time.

Molecular characterization of Salmonella enterica serovar Enteritidis on retail raw poultry in six provinces and two National cities in China.

One hundred and twenty six Salmonella Enteritidis isolates recovered from 1152 retail raw poultries were characterized by antimicrobial susceptibility test, pulsed-field gel electrophoresis (PFGE), presence of quinolone resistance (Qnr) associated genes, Class I integron, extended spectrum beta-lactamases (ESBLs) encoding genes, and mutations in quinolone resistance-determining region (QRDR) of GyrA and ParC. Resistance was most frequently found to nalidixic acid (88.1%), followed by to tetracycline (65.9%), sulfisoxazole (65.1%), and ampicillin (61.9%), and a less extent to cefoxitin (8.7%), gatifloxacin (8.7%), levofloxacin (7.9%), ceftriaxone (7.1%), and ceftiofur (6.3%). One hundred and twenty three (98.4%) isolates were resistant to at least one antibiotic, and 93 (74.4%) to at least four antibiotics. aac(6')-Ib-cr, qnrB, qnrA and qnrS genes were detected in 15 (11.9%), 11 (8.7%), 6 (4.8%) and 1 (0.8%) isolates, respectively. Amino acid substitutions of Ser83Tyr, Asp87Asn, Asp87Tyr, Asp87Gly and Ser83Phe/Asp87Asn were detected in QRDR of GyrA, Arg80Ser was the unique mutation in ParC. Eight isolates were detected with amino acid substitution both in GyrA and ParC. Three isolates carried Class I integron that harboring dfrA17-aadA5, dhfR1-aadA1, and dfrA1, respectively. Five isolates were detected carrying bla(TEM)-bla(ACC) (n = 1), bla(TEM) (n = 1), bla(TEM)-bla(OxA) (n = 3), respectively. Genetic diversities (D = 0.9255) were found among isolates based on PFGE analysis.

Prevalence, distribution, and diversity of Escherichia coli in plants manufacturing goat milk powder in Shaanxi, China.

The aim of the study was to investigate the prevalence, distribution, and diversity of Escherichia coli in goat-milk-powder plants in Shaanxi, China. Three plants manufacturing goat milk powder in Shaanxi province were visited once for sampling during 2012 and 2013. Samples were taken for isolation of E. coli. Isolates were characterized by antimicrobial susceptibility testing and detection of virulence genes. All isolates were further examined by pulsed-field gel electrophoresis analysis. In total, 53 E. coli strains were isolated from 32 positive samples out of 534 samples. Among E. coli isolates, resistance was most frequently observed to trimethoprim-sulfamethoxazole (75.5%), whereas all isolates were sensitive to gatifloxacin, kanamycin, amikacin, and amoxicillin-clavulanate. The 6 virulence genes of pathogenic E. coli were not detected. Pulsed-field gel electrophoresis results showed that E. coli strains in plants were genetically diverse and milk storage tank could be an important contamination source. This study could provide useful information for plants manufacturing goat milk powder to establish proper management practices that help minimize the chance of microbial contamination.

Emergence of ß-lactamases and extended-spectrum ß-lactamases (ESBLs) producing Salmonella in retail raw chicken in China.

ß-Lactamases and extended-spectrum ß-lactamases (ESBLs) producing pathogenic bacteria were widely studied previously in China, but were seldom focused on foodborne Salmonella. In this study, an investigation concerning ß-lactamases and ESBLs producing Salmonella recovered from retail raw chickens was performed. Sixty of 699 foodborne Salmonella isolates were detected as ß-lactamases and ESBLs-producing ones that covered 12 Salmonella serotypes and exhibited different pulsed-field gel electrophoresis genotypes. Forty-four of 60 ß-lactamases and ESBLs-producing strains were simultaneously resistant to ampicillin, amoxicillin/clavulanic acid, ceftiofur, ceftriaxone, and cefoxitin. The most commonly detected ß-lactamases and ESBLs-encoding gene was bla(TEM-1) (n = 44), followed by bla(OXA-1) (n = 38), bla(CMY-2) (n = 29), bla(PSE-1-like) (n = 1), bla(CTX-M-3) (n = 16), and bla(CTX-M-15) (n = 1), respectively. Fourteen, 24, 21, and 1 isolates were detected simultaneously positive for 1, 2, 3, and 4 of the detected ß-lactamases and ESBLs-encoding genes, respectively. A Salmonella strain simultaneously co-carrying bla(TEM-1), bla(OXA-1), bla(CMY-2), and bla(CTX-M-3) was first reported in the present study. Amino acid substitution of Trp244Cys/His247Leu was detected in PSE-1, Val218Asp in CMY-2, and Asp242Gly in CTX-M-15 enzymes, respectively. A difference was found among the amino acid sequences of the detected OXA-1, CMY-2, CTX-M, PSE-1, and TEM-1. The results demonstrated that ß-lactamases and ESBLs were emerging and prevalent in foodborne Salmonella.

Characterization of extended-spectrum beta-lactamases-producing Salmonella strains isolated from retail foods in Shaanxi and Henan Province, China.

Extended-spectrum beta-lactamases (ESBL)-producing Salmonella enterica have been reported worldwide. However, research on foodborne ESBL-producing Salmonella has been rarely conducted. One hundred and thirty eight ceftriaxone or/and cefoperazone-resistant Salmonella strains recovered from retail foods in Shaanxi and Henan Province, China, were screened for ESBL. The ESBL-producing strains were further characterized for antimicrobial resistance, pulse field gel electrophoresis (PFGE) profiles, and the presence of blaTEM, blaSHV, blaOXA, blaCTX-M, and blaPSE. The transferability of ESBL encoding genes to a susceptible Escherichia coli strain was also investigated. Thirty (21.7%) isolates were identified as ESBL positive and belonged to S. enterica serovars Indiana, Shubra, Typhimurium, and Enteritidis. S. Indiana and S. Shubra isolates were firstly identified in ESBL-producing strains. Great genetic diversity was seen among these ESBL-producing strains. Nucleotide sequence analysis revealed that blaTEM-1B was the only ESBL-encoding gene among the genes tested and was detected in 26 of 30 strains and was carried in the conjugative plasmids. The blaTEM-1B gene was transferable through conjugation at rates ranging from 4.71 × 10(-7) to 7.55 × 10(-6) transconjugant per recipient cell. This study provides the evidence of foodborne ESBL-producing Salmonella, and the transferability of plasmid harboring ESBL-encoding genes could possibly contribute to the dissemination of ESBL.

Antimicrobial susceptibility and molecular typing of methicillin-resistant staphylococcus aureus in retail foods in Shaanxi, China.

The aims of this study were to evaluate the occurrence of methicillin-resistant Staphylococcus aureus (MRSA) in retail foods in Shaanxi, China and to investigate antimicrobial resistance and molecular characteristics of these strains. A total of 1979 retail food samples were randomly collected during 2008-2012 from supermarkets and farmers markets and screened for S. aureus, and then S. aureus isolates were further examined to determine whether they were MRSA. MRSA isolates were further characterized by antimicrobial susceptibility test, pulsed-field gel electrophoresis, spa typing, multilocus sequence typing, and SCCmec typing, and were examined for genes encoding enterotoxins, exfoliative toxins, Panton-Valentine leukocidin (pvl), and toxic shock syndrome toxin 1. Among all the samples examined, four (1.4%) raw milk samples, six (2.3%) chicken samples, one (0.6%) pork sample, three (0.6%) ready-to-eat food samples, and three (2.5%) dumpling samples were positive for MRSA. No MRSA isolates were recovered from infant foods. A total of 23 MRSA isolates were recovered from the 17 MRSA-positive samples. Antimicrobial susceptibility tests showed that, among these MRSA isolates, resistance was most frequently observed to penicillin, ampicillin, oxacillin, cefoxitin, and clindamycin (each 100%), followed by erythromycin (95.7%) and clarithromycin (87.0%). The commonly detected toxin genes were pvl, seg, seb, sed, followed by see, sec, and sei. Seven spa types (t189, t377, t437, t899, t10793, t5762, and a new spa type) and three SCCmec types (II, IVb, and V) were identified. More than half (52.2%) of the MRSA isolates belonged to ST9, followed by ST88, ST59, ST188, ST72, and ST630. Our findings indicate that MRSA in food could be from both animal and human origin. Although the prevalence is low, the presence of multidrug resistant and enterotoxigenic MRSA strains in foods poses a potential threat to consumers and emphasizes the need for better control of sources of contamination.

Prevalence, distribution, and diversity of Escherichia coli, Staphylococcus aureus, and Salmonella in kiwifruit orchards and processing plants.

The aim of the study was to investigate the prevalence, distribution, and diversity of three foodborne bacteria in kiwifruit orchards and processing plants. Fourteen kiwifruit orchards and two processing plants in Shaanxi province were visited for sampling in 2012. Fruit samples and environmental samples in orchards and plants were taken for isolation of Escherichia coli, Staphylococcus aureus, and Salmonella. All isolates were characterized by antimicrobial susceptibility testing and detection of virulence genes. Selected isolates were further examined by pulsed-field gel electrophoresis (PFGE) analysis. In total, 160 E. coli isolates and 14 S. aureus isolates were recovered from 407 samples from orchards and plants, while no Salmonella was recovered. E. coli isolates displayed resistance most frequently to streptomycin (65.6%), and S. aureus isolates displayed resistance most frequently to erythromycin (21.4%). Three E. coli isolates (1.9%) were positive for stx2 and two S. aureus isolates (14.3%) were positive for both seb and seh. Seventy-seven E. coli isolates and 14 S. aureus isolates were analyzed by PFGE. PFGE results showed that both E. coli and S. aureus isolates were diverse, and blades for slicing during the processing could be an important contamination source. This study could provide useful information for kiwifruit growers and industry to establish proper management practices that help minimize the chance of microbial contamination from farm to table.

Presence of qnr, aac(6')-Ib, qepA, oqxAB, and mutations in gyrase and topoisomerase in nalidixic acid-resistant Salmonella isolates recovered from retail chicken carcasses.

Four hundred sixty-two nalidixic acid- and/or ciprofloxacin-resistant Salmonella isolates were examined for presence of quinolone-resistance mechanisms. A total of 339 amino acid substitutions were identified in GyrA (204) and ParC (135). Ser83Phe/Asp87Gly (29.4%) were most commonly detected in GyrA in 136 isolates, and to a lesser extent of Asp87Asn (22.8%), Asp87Gly (19.1%), Ser83Phe/Asp87Asn (19.1%), and Ser83Tyr (5.1%). Ser80Arg (97.0%) was detected in ParC in 132 isolates. Simultaneous mutations in GyrA and ParC (n=109) were commonly detected to be Ser83Phe/Asp87Gly(GyrA)-Ser80Arg(ParC) (35.8%), Asp87Asn(GyrA)-Ser80Arg(ParC) (22.9%), and Ser83Phe/Asp87Asn(GyrA)-Ser80Arg(ParC) (21.1%). qnrA, qnrB, qnrS, aac(6')-Ib, qepA, and oqxAB were detected in 52 (11.3%), 64 (13.9%), 11(2.4%), 107 (23.2%), 6 (1.3%), and 194 (42.0%) of 462 isolates, respectively. Isolates carried more qnr, aac(6')-Ib, qepA, and oqxAB genes, and amino acid substitution in GyrA and ParC was more resistant to nalidixic acid and fluoroquinolones.

Isolation and characterization of Listeria monocytogenes isolates from retail foods in Shaanxi Province, China.

Listeria monocytogenes is an important foodborne pathogen of public health concern. A total of 902 retail food samples, including 342 ready-to-eat (RTE) foods, 366 infant foods, and 194 raw chickens were collected randomly in supermarkets and farmers' markets in 12 geographic areas in Shaanxi Province, China and screened for L. monocytogenes. All L. monocytogenes isolates were characterized by antimicrobial susceptibility testing, serotyping, and pulsed-field gel electrophoresis (PFGE). Twenty-seven (3.0%) samples were positive for L. monocytogenes, and 39 L. monocytogenes isolates were recovered from positive samples. Of these L. monocytogenes isolates, 21 isolates (53.8%) showed resistance to at least one antimicrobial. The isolates displayed resistance most frequently to oxacillin (18 isolates, 46.2%), followed by tetracycline (five isolates, 12.8%), erythromycin (four isolates, 10.3%), trimethoprim/sulfamethoxazole (three isolates, 7.7%), chloramphenicol (two isolates, 5.1%), and vancomycin (one isolate, 2.6%). All isolates were sensitive or displayed intermediate resistance to gentamicin, ampicillin, ciprofloxacin, and amikacin. Four serotypes including serotype 1/2b, 4b, 4e, and 1/2a were identified in those foodborne isolates. PFGE analysis demonstrated that some isolates with the same PFGE patterns came from different food sources, and isolates from the same food source tend to cluster closely. Presence of L. monocytogenes of clinically important serotypes in retail foods and their antimicrobial resistance constitute a potential risk for the public. Appropriate measures should be taken by government, industry, and consumers to reduce the risk posed by this ubiquitous pathogen.

Antimicrobial susceptibility testing and genotypic characterization of Staphylococcus aureus from food and food animals.

Staphylococcus aureus is commonly present in humans and animals. The aim of this study was to investigate antimicrobial resistance and genetic characteristics of S. aureus from food and food animals in Shaanxi Province in China. A total of 332 nasal swabs, breast skin swabs, raw milk, and pork samples were collected from local pig, dairy farms, or local grocery stores and screened for the presence of S. aureus. S. aureus isolates were characterized using antimicrobial susceptibility, pulsed-field gel electrophoresis (PFGE) analysis, and polymerase chain reaction for detecting pvl and mecA genes. Methicillin-resistant S. aureus (MRSA) strains were additionally tested for SCCmec type and exfoliative toxin genes. The prevalence of S. aureus was 30.6% in pig nasal swabs, 32.5% in pork, 25.7% in cow nasal swabs, 30.8% in cow breast skin swabs, and 29.3% in milk samples. Resistances were common among isolates tested against erythromycin (65.7%), tetracycline (65.7%), ciprofloxacin (52.7%), followed by gentamicin (36.7%), chloramphenicol (23.1%), cefoxitin (8.3%), and oxacillin (7.7%), but no isolate was resistant to vancomycin, amikacin, or cefoperazone. pvl gene was found in the isolates from all types of samples except from cow nasal swabs. Fourteen isolates from pig nasal swabs contained mecA gene and were considered as MRSA. PFGE analysis showed that nasal isolates differed from food isolates, but isolates from the same animal source appeared to cluster closely. The PFGE patterns of MRSA isolates were different from other S. aureus isolates from pig nasal cavity even though they were from the same source. All the MRSA isolates belonged to SCCmec type IV(b). No isolates contained exfoliative toxin genes. These findings indicated that S. aureus, including multidrug-resistant S. aureus, are widely spread in food animals and animal-derived foods in Shaanxi Province, China. MRSA isolates from pigs may pose potential health risks for workers in swine farms and the community at large.

[Drug resistance and related genes of chickenborne Salmonella to quinolone and fluoroquinolones].

OBJECTIVE: Antimicrobial susceptibility to quinolone and fluoroquinolones and the related genes of chickenborne Salmonella in Shaanxi, Henan, Sichuan and Beijing provinces were studied to better understand the development of antimicrobial resistance and routes of transmission to ensure food safety. METHODS: Antimicrobial susceptibility was tested according to agar dilution method. GyrA and parC gene mutations of quinolone resistance determination region (QRDR) of fluoroquinolone resistant Salmonella and the resistant genes of qnrA, qnrB, qnrS and aac (6')-Ib-cr were determined using PCR and DNA sequencing analysis. RESULT: Among the 390 Salmonellae isolates, 63.59% were resistant to nalidixic acid, followed by ciprofloxacin (21.28%), levofloxacin (16.67%), and gatifloxacin (14.62%). Among 248 nalidixic acid resistant Salmonella, antimicrobial resistant genes carried by plasmid were detected as aac(6')-Ib-cr (20.16%), qnrA (10.89%), qnrB (10.08%) and qnrS (1.61%), respectively. In total 199 point mutations were detected in gyrA and parC of 83 fluoroquinolone-resistant Salmonella isolates. The most common mutations in gyrA gene was Ser83Phe and Asp87Gly double mutation, followed by Ser83Phe and Asp87Asn double mutation, Ser83Tyr, Ser83Phe, Asp87Gly. Sixty-five point mutations detected in parC was Ser80Arg. CONCLUSION: Antimicrobial resistance of Salmonella recovered from chicken in the four provinces was common. Genetic elements including mutations of unwindase, topoisomerase, and plasmid with antimicrobial, played important roles in the antimicrobial resistance of Salmonella.

Therapeutic Role of Retroperitoneal Lymphadenectomy in 170 Patients With Ovarian Clear Cell Cancer.

INTRODUCTION: We evaluated the therapeutic role of retroperitoneal lymphadenectomy in patients with ovarian clear cell cancer (OCCC). MATERIALS AND METHODS: We retrospectively reviewed 170 OCCC patients diagnosed at two hospitals in China between April 2010 and August 2020. Clinical data were abstracted, and patients were followed until February 2021. Patients were divided into retroperitoneal lymphadenectomy and no lymphadenectomy groups. The Kaplan-Meier method was used to compare progression-free (PFS) and overall survival (OS) between the two groups. Statistical differences were determined by the log-rank test. The COX proportional hazards regression model was applied to identify predictors of tumor recurrence. RESULTS: The median age was 52 years; 90 (52.9%) and 80 (47.1%) patients were diagnosed as early and advanced stage, respectively. Clinically positive and negative nodes was found in 40 (23.5%) and 119 (70.0%) patients, respectively. Of all the 170 patients, 124 (72.9%) patients underwent retroperitoneal lymphadenectomy, while 46 (27.1%) did not. The estimated 2-year PFS and 5-year OS rates were 71.4% and 65.9% in the lymphadenectomy group, and 72.0% and 73.7% in no lymphadenectomy group (p = 0.566 and 0.669, respectively). There was also no difference in survival between the two groups when subgroup analysis was performed stratified by early and advanced stage, or in patients with clinically negative nodes. Multivariate analysis showed that retroperitoneal lymphadenectomy were not an independent predictor of tumor recurrence. CONCLUSION: Retroperitoneal lymphadenectomy provided no survival benefit in patients diagnosed with OCCC. A prospective clinical trial is needed to confirm the present results.

Primary Laparoscopic Surgery Does Not Affect the Prognosis of Early-Stage Ovarian Clear Cell Cancer.

PURPOSE: Minimally invasive surgery (MIS) is performed frequently in early-stage ovarian cancer patients, especially in ovarian clear cell carcinoma (OCCC). The aim of this study was to investigate whether primary laparoscopic surgery influences prognosis in patients with early-stage OCCC. PATIENTS AND METHODS: Patients with International Federation of Gynecology and Obstetrics (FIGO) stage I  OCCC were retrospectively reviewed in two hospitals between April 2010 and August 2020. Clinical data were abstracted, and patients were followed up until February 2021. Patients were divided into open surgery (laparotomy) and laparoscopy groups, and the Kaplan-Meier method was applied to compare progression-free survival (PFS) and overall survival (OS) between the groups. Statistical differences were determined by the Log rank test. RESULTS: Eighty-nine patients were included in the study; 20 (22.5%) and 69 (77.5%) patients underwent laparoscopic and open surgery, respectively. The patients' characteristics were well-balanced except that patients in the laparoscopy group tended to have smaller tumors and lower frequency of omentectomy and lymphadenectomy compared with the open surgery group. The median follow-up duration was 42.6 and 36.5 months in the laparoscopy and open surgery groups, respectively. Nine (10.1%) patients developed recurrence, and 4 (4.5%) died of the disease; all in the open surgery group. The estimated 2-year PFS rates were 100.0% and 90.1%, and the estimated 5-year OS rates were 100.0% and 91.9% in the laparoscopy and open surgery groups, respectively. No significant survival differences were found between the groups. CONCLUSION: Survival was not compromised when primary laparoscopic surgery was performed in early-stage OCCC patients. A well-designed randomized controlled trial is warranted.

[Antimicrobial susceptibility and related genes of Salmonella serovars from retail food in Shaanxi province].

OBJECTIVE: Salmonella isolates from retail food were examined for antimicrobial susceptibility and further characterized to better understand the development and dissemination of antimicrobial resistance among foodborne Salmonella in China. METHODS: Antimicrobial susceptibility of 359 Salmonella isolates was determined by using agar dilution methods recommended by the Clinical and Laboratory Standards Institute. Antimicrobial resistance integrons and resistance genes were identified using PCR. Mutations in gyrase and Topoisomerase genes related to fluoroquinolones resistance were also determined using PCR and gene sequencing analysis. RESULTS: Among the 359 Salmonellae isolates, 67% were resistant to Sulfamethoxazole, followed by resistant to trimethoprim/Sulfamethoxazole (58%), tetracycline (56%), kanamycin (37%), nalidixic acid (35%), ampicillin (33%), amoxicillin/clavulanic acid (32%), streptomycin (29%), chloramphenicol and gentamicin (26%), ciprofloxacin (21%), ceftriaxone (16%), cefoxitin (9%) and cefoperazone (8%). Among the 284 resistant isolates, 79% were resistant to at least one antimicrobial, 25.9% to 10 or more than 10 antimicrobials, and 2.5% to 14 antibiotic agents. Integrons were detected in some of sulfamethoxazole-ressitant Salmonella, and the most common integron was 1.4 kb, Antimicrobial resistance genes carried by integrons included aadA1, aadA2, aadA5, tetR, blaPSE1, blaDHA1, blaVEB-1, dhfr I, dhfr V, dhfrVl and dhfr17. The blaTEM gene was also detected in 51.6% of 62 ceftriaxone and/or cefoperazone resistant isolates, and blacMY-2 was detected in 56.5% of the isolates. 13.6% of the Salmonella isolates carried Salmonella Gene Island. Sixty-eight point mutations were detected in gyrA, parC and parE of 35 fluoroquinolone-resistant Salmonella isolates. The common mutations in gyrA gene were Ser83Phe, Ser83Tyr, Asp87Gly and Asp87Asn, whereas ser80Arg was detected in parC. Mutations including Lys441 Ile, Lys428Gln, Asp494Asn, Lys428Gln and Gly442Ser were detected in parE, which was first reported in Salmonella. CONCLUSION: Antimicrobial resistance of Salmonella recovered from food in Shaanxi province was common. Several genetic elements including integron, Salmonella Gene Island, beta-lactamase genes and mutations in gyrase and topoisomerase genes played an important role in antimicrobial resistance of Salmonella.

Knockdown of Ezrin inhibited migration and invasion of cervical cancer cells in vitro.

Cervical cancer is the fourth most common malignancy in women. The aim of this study was to investigate the functions of Ezrin in cervical cancer cells. Two cervical cancer cell lines, SiHa and CaSki, were cultured in vitro. Following the knockdown of Ezrin using siRNA, real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis were applied to analyze Ezrin expression at the messenger RNA (mRNA) and protein levels. Subsequently, wound healing assay, transwell assay, and sulforhodamine B (SRB) assay were used to detect the migration, invasion, and viability of cervical cancer cells, respectively. Results revealed that Ezrin siRNA can notably inhibit the migration and invasion of SiHa and CaSki cells (P < 0.05). However, knockdown of Ezrin shows no effects on the viability of SiHa and CaSki cells (P < 0.05). It is indicated that Ezrin plays a possible role in promoting the migration and invasion of cervical cancer cells and may be a therapeutic target to prevent metastasis of cervical cancer.

An enhanced discriminatory pulsed-field gel electrophoresis scheme for subtyping Salmonella serotypes Heidelberg, Kentucky, SaintPaul, and Hadar.

Conventional pulsed-field gel electrophoresis (PFGE) protocols, used extensively as a successful approach for subtyping many salmonellae, may be inadequate for discriminating strains sharing levels of homogeneity within the same serotype. Four additional restriction enzymes (SpeI, PacI, SfiI, and NotI), in addition to XbaI and BlnI, were used in PFGE typing of 33 Salmonella Heidelberg, 27 Salmonella Kentucky, 27 Salmonella SaintPaul, and 27 Salmonella Hadar isolates that were recovered from poultry and porcine retail meats from different states of the United States. A dendrogram derived from the combined analysis of six enzymes was highly discriminatory with a Simpson index of diversity value of over 0.950. The ratio of nodes to isolates was more than 0.75 with an average of fewer than three isolates in each polytomy for all four serotypes. Two three-enzyme combinations, SpeI/NotI/SfiI for Salmonella Heidelberg and Salmonella Hadar, and SpeI/BlnI/SfiI for Salmonella Kentucky and Salmonella SaintPaul, were found to have comparable discriminatory abilities of differentiating isolates of these Salmonella serotypes with the six-enzyme combination. The enhanced discriminatory PFGE-based subtyping scheme can be used effectively for the differentiation of strains of the four Salmonella serotypes. The findings also highlight PFGE analysis as a continued essential and informative subtyping method for source tracking and outbreak investigations of these and other Salmonella pathogens.

[Detection and analysis of antibiotic resistance of Salmonella from retail meats in some districts of Shaanxi province].

OBJECTIVE: Salmonella isolates recovered from retail meats that were collected in supermarkets and free markets in Xi'an and Yangling areas of Shaanxi province were studied to determine antibiotic susceptibility. METHOD: Antimicrobial susceptibility to 14 antibiotics of 193 salmonella isolates were determined by using agar dilution method, which was recommended by National Committee of Clinical Laboratory Standard (NCCLS), and E.coli ATCC25922 and E.faecalis ATCC29212 as standard control strains. RESULTS: The 44.6% of the salmonella isolates were resistant to sulfamethoxazole, followed by resistance to kanamycin (40.9%), tetracycline (37.8%), amoxicillin (26.9%), ampicillin (25.4%), gentamicin (23.3%) and chloramphenicol (21.8%). Some isolates also showed resistance to fluoroquinolones, the rates for ciprofloxacin, enrofloxacin, levofloxacin and gatifloxacin were 22.3%, 21.8%, 20.8% and 21.2%, respectively. 55 isolates (28.5%) were multidrug resistant (MDR) strains, 28 of 193 isolates (14.5%) could resist at least 13 antibiotics, 24 isolates (12.4%) were resistant to from 4 to 12 antibiotics. CONCLUSION: Salmonella isolates recovered from retail meats in Xi'an district of Shaanxi province were seriously resistant to antimicrobials commonly used as human and veterinary medicine.

[Identification of antimicrobial susceptibility of foodborne Salmonella and related plasmid].

OBJECTIVE: We tested the antimicrobial susceptibility of 390 Salmonella isolates. We also studied the relationship between plasmids in some multidrug resistant Salmonella isolates and the antibiotic resistance profile of their hosts, as well as conjugation test of some multidrug resistant Salmonellas. METHODS: Salmonella strains were isolated by using selective cultures, putative Salmonella was confirmed by PCR. Antimicrobial susceptibility was tested according to the National Committee for Clinical Laboratory Standards. Plasmid of some representative multidrug resistant strains was isolated by using QIAGEN Plasmid Mini Kit and digested with Hind III. The plasmid profiles were acquired by gel electrophoresis and analyzed by DPS. The conjugation test was done to illustrate the function of plasmid during the antibiotic resistance transfer. RESULTS: Of the Salmonella isolates, 58.2% were resistant to tetracycline, followed by resistance to streptomycin (42.8%), kanamycin (39%), ampicillin (38.2%), cefoxitin (27.2%), chloramphenicol (26.9%), gentamicin (21%), ceftriaxone (19%), amoxicillin-clavulanic (18.2%), trimethoprim-sulfamethoxazole (17.9%), ceftiofur (14.6%) and nalidixic acid (12.3%). There was no strict corresponding relationship between antibiotic resistance profile of the host Salmonella and its plasmid profile. The conjugation frequency of the plasmid was from 2.4 x 10(-4) to 5.6 x 10(-1). CONCLUSION: Antimicrobial resistance is common in foodborne Salmonella, direct relativity does not exist between the homology of plasmids and their hosts' antibiotic resistance phenotype, antibiotic resistant genes in the plasmid can transfer from donor to the recipient in interspecies and intraspecies with high frequency accompanying conjugation.

Primary small cell neuroendocrine carcinoma of the Bartholin's gland: A case report.

Primary carcinoma of the Bartholin's gland (BG) is a rare malignancy. There are extremely rare cases of small cell neuroendocrine carcinoma (SCNC) of the BG reported in the English literature. A postmenopausal female presented with a 1-month history of increasing pain and swelling on the left vulva consistent with spontaneously bleeding. Pathology identified SCNC that arose in BG. The patient was treated with a radical wide local excision and bilateral inguinal lymph node dissection followed by six courses of chemotherapy. One month after primary treatment, without any pelvic recurrence or abnormal tumor markers indications, distant metastasis of the liver was diagnosed and VI hepatic lobectomy was performed. The patient maintained regular adjuvant chemotherapy every month under outpatient surveillance and has no local recurrence or distant metastasis.