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The body is in a very complex pathophysiological state under trauma, including ischemia and hypoxia, inflammation caused by infection and tissue necrosis and accumulation of metabolic waste. Metastasis associated lung adenocarcinoma transcript 1 (MALAT1) is involved in the regulation of a variety of cell behaviors, such as proliferation, apoptosis, differentiation, migration, epithelial-mesenchymal transition, autophagy and morphological maintenance. Under trauma, the expression of MALAT1 is significantly increased. In different injury models, the role of MALAT1 is slightly different, and the specific mechanism is unknown. The authors summarize the regulatory effects of MALAT1 on the body under traumatic conditions from the biological characteristics of MALAT1 and its role in different injury models, so as to provide references for clinical control of inflammation development and improvement of disease prognosis.
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Objective To analyze the safety of indwelling neonatal umbilical vein catheter (UVC) at high or low tip positions.Methods We retrospectively analyzed 155 neonates with indwelling UVC in Guangdong Women and Children Hospital from March 2015 to May 2016.According to the position of the catheter tip,these infants were divided into high position group (the tip was at the same level as the central vein) or low position (the tip was below the portal vein) group.Several parameters including indwelling time,liver function,liver B-ultrasound and catheter-related bloodstream infections in the two groups were analyzed.Data were statistically analyzed using Mann-Whitney U test,Wilcoxon signed rank sum test or Chi-square test.Results (1) A total of 155 infants were enrolled in this study.Their gestational age ranged from 25 to 41 weeks and their birth weight were 700 g to 4 690 g.UCV was inserted at the age of 0.5-8.0 d for 0-12 d.In the low position group,seven cases ended in early extubation due to fluid extravasation caused by shallow insertion.The indwelling time of the low position group was shorter than that of the high position group [M (P25-P75),6 (4-7) d and 7 (5-7) d,Z=-2.580,P=0.010].There were no significant differences in gender,gestational age,birth weight,and age at catheterization between the two groups.(2) No abnormality in the two groups was revealed by liver ultrasound.Complications such as neonatal necrotizing enterocolitis,thrombosis and embolism,air embolism and liver abscess were not reported.The proportion of liver function abnormalities in the high group was 6.9％ (6/87),which was not statistically significant as compared with 4.4％ (3/68) in the low position group (3x2=0.431,P=0.512).(3) Blood culture was performed for all cases,of which 116 (74.8％) were catheter culture (including 71 in the high position group and 45 in the low position group).The incidence of catheter-related bloodstream infection in the high position group was 5.6％ (4/71) and the infection rate was 7.4 per thousand catheter days,while in the low position group these figures were 6.7％ (3/45) and 8.0 per thousand catheter days,respectively.There was no significant difference between the two groups (x2=0.052,P=0.820).(4) Results of catheter culture showed that seven cases were positive,including three for Staphylococcus haemolyticus (two in low position group and one in high position group),one for yeast-like fungus (high position group),one for Enterococcus faecium (high position group),one for Staphylococcus aureus (high position group) and one for Candida albicans (low position group).Conclusions The indwelling time of UVC at high tip position is longer than that at low position,and although there are no differences between the complications and the incidence of catheter-related bloodstream infection in the two groups,but its safety needs further study.
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Objective To understand the circulation,drug resistance and molecular characteristics of Salmonella 1,4,[5],12:i:-in human in Guangdong province.Methods Salmonella 1,4,[5],12:i:-isolated from diarrhea patients in Guangdong during 2007-2016 were detected for drug resistance,genes and PFGE characteristics.Results A total of 2 960 strains Salmonella 1,4,[5],12:i:-were isolated from human diarrhea cases during this period.The positive rates of the isolation increased year by year.The male to female ratio of the infection cases was 1.58 ∶ 1,and the infection mainly occurred in infants and young children.Except imipenem,Salmonella 1,4,[5],12:i:-was resistant to other 17 antibiotics to some extent.The drug resistant rates to ceftazidime,cefotaxime and ciprofloxacin increased from 2011 to 2016.Multi-drug resistance was serious,for example,the multi-drug resistant strains with ASSuT accounted for 70.62％ (435/616) and the multi-drug resistant strains with ACSuGSTTm accounted for 27.11％ (167/616).The lack offljA,fljB and hin genes,as well as the retaining of iroB,STM2740,STM2757 genes,resulted in the unable expression of FljBenx gene with 8 different defection profiles.There were 934 different PFGE patterns observed in 2 347 strains,which displayed a relatively large fingerprint polymorphism.The major PFGE pattern was JPXX01.GD0226,which was found in 97 strains,accounting for 4.13％ (97/2 347).The PFGE patterns in 168 Salmonella 1,4,[5],12:i:-strains were consistent with that of Salmonella typhimurium.Conclusions Salmonella 1,4,[5],12:i:-strains has become the major serotype of Salmonella that cause diarrhea in human in Guangdong.The multi-drug resistance of Salmonella 1,4,[5],12:i:-was serious,and since the defection offljA,fljB and hin genes,the expression of FljBenx protein failed.The PFGE results were diverse,which displayed polymorphism in inheritance.
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Objective To investigate the infection status, serotype distribution, drug sensitivity and molecular characteristics of diarrheagenic Escherichia coli (DEC) in patients with diarrhea in Guangdong Province. Methods Fecal samples were collected, cultured and isolated by traditional methods. Suspected Escherichia coli isolates were confirmed by multiplex PCR used for detecting specific virulence genes and bio-chemical methods. Positive strains were serotyped, characterized for drug sensitivity and analyzed by pulsed-field gel electrophoresis ( PFGE). Results The total positive rate of DEC in patients with diarrhea was 6.26%. The positive rates of enteropathogenic Escherichia coli (EPEC), enterotoxigenic Escherichia coli (ETEC), enterohemorrhagic Escherichia coli (EHEC), enteroadherent Escherichia coli (EAEC) and en-teroinvasive Escherichia coli (EIEC) were 2. 47% , 1. 54% , 1. 32% , 0. 62% and 0. 09% , respectively, with infections primarily in children aged 0-<7 years. The total seropositive rate was 52. 54% , with EHEC accounting for 15. 00% . DEC showed high sensitivity to imipenem, ciprofloxacin, ceftazidime and cefo-taxime. The multidrug resistance rate of DEC was 58. 45% , with EPEC being the most serious for multidrug resistance. PFGE results showed that ETEC, EHEC, EPEC and EAEC had a high degree of polymorphism. Conclusion EPEC is the predominant type of DEC circulating in Guangdong Province. Third-generation cephalosporins are the first drugs of choice for treating infections in children. Ciprofloxacin can be used to treat adults. The problem of multiple drug resistance of DEC is severe and efforts to monitor DEC infections and drug resistance should be strengthened.
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Objective To understand the circulation,drug resistance and molecular characteristics of Salmonella 1,4,[5],12:i:-in human in Guangdong province.Methods Salmonella 1,4,[5],12:i:-isolated from diarrhea patients in Guangdong during 2007-2016 were detected for drug resistance,genes and PFGE characteristics.Results A total of 2 960 strains Salmonella 1,4,[5],12:i:-were isolated from human diarrhea cases during this period.The positive rates of the isolation increased year by year.The male to female ratio of the infection cases was 1.58 ∶ 1,and the infection mainly occurred in infants and young children.Except imipenem,Salmonella 1,4,[5],12:i:-was resistant to other 17 antibiotics to some extent.The drug resistant rates to ceftazidime,cefotaxime and ciprofloxacin increased from 2011 to 2016.Multi-drug resistance was serious,for example,the multi-drug resistant strains with ASSuT accounted for 70.62％ (435/616) and the multi-drug resistant strains with ACSuGSTTm accounted for 27.11％ (167/616).The lack offljA,fljB and hin genes,as well as the retaining of iroB,STM2740,STM2757 genes,resulted in the unable expression of FljBenx gene with 8 different defection profiles.There were 934 different PFGE patterns observed in 2 347 strains,which displayed a relatively large fingerprint polymorphism.The major PFGE pattern was JPXX01.GD0226,which was found in 97 strains,accounting for 4.13％ (97/2 347).The PFGE patterns in 168 Salmonella 1,4,[5],12:i:-strains were consistent with that of Salmonella typhimurium.Conclusions Salmonella 1,4,[5],12:i:-strains has become the major serotype of Salmonella that cause diarrhea in human in Guangdong.The multi-drug resistance of Salmonella 1,4,[5],12:i:-was serious,and since the defection offljA,fljB and hin genes,the expression of FljBenx protein failed.The PFGE results were diverse,which displayed polymorphism in inheritance.
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@#Type 1 diabetes mellitus(T1DM)is an autoimmune disease characterized by the destruction of β cells and insulin absolutely deficiency upon antigen-specific T lymphocyte attack. The patients with T1DM need insulin therapy for the whole life. Although the mechanism of T1DM is still unclear now, environmental factors play a critical role in the T1DM development because the incidence of infectious diseases is opposite to that of allergies and autoimmune diseases. So far, a variety of bacteria, parasites, viruses and their composition have been proved functional in the prevention of T1DM in animal models. Therefore, microbial vaccine, if administrated early, can induce immune tolerance and prevent the destruction of pancreatic islet β cells, which is expected to be safe and effective novel approach in treating T1DM. This paper summarizes several types of T1DM microbial vaccine and their potential mechanisms including inactivated vaccine, attenuated vaccine, subunit vaccine, DNA vaccine and living-vector vaccine.
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Objective To investigated the etiologic characteristics of Shigella (S.) sonnei strains causing outbreaks and sporadic cases in some areas of Guangdong province and Guangxi Zhuang Autonomous Region during 2014-2016. Methods Fourteen S. sonnei strains isolated from outbreaks and 6 S. sonnei strains from sporadic cases from Guangdong and Liuzhou of Guangxi Zhuang Autonomous Region were tested for antimicrobial resistance and analyzed by pulsed-field gel electrophoresis (PFGE). Six typical strains were selected for whole genome sequencing typing and compared with 51 strains isolated both at home and abroad from NCBI genome database. Results The antibiotic resistance test indicated the isolates had high resistance rate to ampicillin, tetracycline, gentamicin, trimethoprim/sulfamethoxazole and nalidixic acid, while sensitive to azithromycin, chloromycetin and imipenem. PFGE showed high similarity (93.2%) among the strains isolated from different areas. The whole genome sequencing analysis also revealed that all the typical strains wereclustered into a same evolution branch, close to some strains from Korea. Conclusions The S. sonnei strains isolated from some areas of Guangdong and Guangxi Zhuang Autonomous Region showed high resistance to commonly used antibiotics, but they were sensitive to azithromycin, chloramphenicol and imipenem. The isolates in this study also showed similar PFGE patterns and close phylogenic evolution.
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Objective To explore an ideal surgical method for mid-low face lifting.Methods In this procedure,the first surgical step was subcutaneous undermining that was performed through the incision along temporal hairline,anteriorear,and mastoideae.It extended distally beyond the furthest skin fold and along the mandibular border or the midline of the neck if nacessary.Then three layers suspension were performed,which included three procedures:first,SMAS was purse string sutured in certain direction;secondly,the malar fat pad was suspended to tow directions backward and upward and anchored in the periosteum of zygoma and SMAS too;lastly,through traction suture of reducing tension step-by-step,lots of the tension was relieved from the incision;at the same time,new retaining ligaments between flap and SMAS were reestablished.And redundant skin was removed in incision at the end of the procedure.Results A total of 22 cases received this operation.16 cases were followed up from 3 months to 24 months after operation.The results of operation were divided into three degrees:excellent,acceptable and poor;and those were evaluated by patients themselves.14 cases obtained excellent result (87.5 ％),2 cases regarded that their results were acceptable (12.5 ％).The total satisfactory rate was 100 ％.None serious complication occurred in those eases except some slight complications,such as local edema,skin numbness and small hematoma which relieved in 3 to 6 months after operation.Scar was inconspicuous.Conclusions This technique can correct the posies of lower tow-third face better,especially for mitigating the nasolabial fold and enhancing the elastic of face skin.Simultaneously,it is an effective,safe and simple technique.
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In order to study the relationship between Staphylococcal nuclease(SNase) and diabetes mellitus,genetic engineering bacteria E.coli BL21/pET28a-His-SNase was constructed,the expression of soluble extracellular protein SNase was induced and the a preliminary research was made on it.An expression vector pET28a-His-SNase plasmid containing the His-SNase gene was constructed and transformed into E.coli BL21 (DE3) competent cells.The protein was induced by lactose and purified by ultrasound destruction and Ni-affinity chromatography,respectively.It was then analyzed by SDS-PAGE and Western blot.The enzymatic properties for SNase has been preliminary studied as well.Results indicated that the purity of the correctly expressed fusion protein HisSNase was over 85％.SNase showed good activity within a wide range of pH and good heat resistance.This experiment might be a foundation work for the further study on the relationship between SNase and with diabetes.
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Objective To analyze the serotype distribution and antibiotic resistance characteristics of Salmonella strains isolated in Guangdong province for better understanding the condition of Salmonella infection in patients with diarrhea.Methods Fecal samples collected from patients with diarrhea in Guangdong province were used to isolate Salmonella strains.Biochemical analysis was performed to identify these isolated strains.Serotyping and antimicrobial susceptibility testing were carried out for further analysis of the isolated Salmonella strains.Results The rate of Salmonella infection was 7.64％in 2015, and the male to female patient ratio was 1.52∶1.A total of 2 377 patients of all age groups were positive for Salmonella infection and the patients aged 0-6 years accounted for 81.74％.The isolation rate of Salmonella strains in the summer and autumn was higher than that in the winter and spring (10.73％ vs 4.24％;X2=463.77, P<0.01).The Salmonella isolation rates in different areas were as follows: 16.82％ in Zhuhai, 15.85％ in Heyuan, 11.81％ in Yangjiang, 10.68％ in Jiangmen, 8.49％ in Zhongshan, 8.07％ in Maoming, 8.05％ in Jieyang, 7.35％ in Shaoguan, 6.97％ in Foshan, 6.03％ in Dongguan, 5.48％ in Guangzhou and 0.00％ in Zhanjiang.And the differences between different regions were statistically significant (X2=367.67, P<0.01).The 2 377 isolated Salmonella strains were classified into 108 serotypes except for oneSalmonella strain that could not be classified.The top four predominant serotypes were 4,5,12:i:-, Salmonella enteritidis,Salmonella stanley and Salmonella typhimurium.Most Salmonella strains were sensitive to imipenem, azithromycin, ceftazidime, cefotaxime and trimethoprim/sulfamethoxazole, but multidrug resistance was common among those strains.Conclusion Salmonella serotypes of 4,5,12:i:-and Salmonella enteritidis are the predominant pathogens causing human Salmonella infections in Guangdong province.Ceftazidime and cefotaximeare are preferred in the treatment of Salmonella infections.Surveillance for drug resistance in Salmonella should be strengthened as multidrug resistant strains have become a serious problem in Guangdong province.
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Objective@#To explore the clinical application of home-made temporomandibular joint (TMJ) prostheses.@*Methods@#Self-developed TMJ prostheses were applied for end stage osteoarthritis, TMJ ankylosis, condylar tumors after biomechanical examination. The stability of the prostheses toward bone was evaluated during operation. Post-operative CT scans and clinical follow-ups were taken to check changes of mouth opening, position of the prostheses, bone resorption around the screws, and heterotopic bone formation around artificial condyle.@*Results@#There were 6 patients accepted 7 prostheses smoothly without infection and other complications. Post-operative follow-ups were from 6 to 13 months with a mean of 7.6 months. Mouth opening was significantly improved from (16.2±14.4) mm before operation to (31.5±4.8) mm during follow-ups (P=0.01). All prostheses were stable without screw loose and heterotopic bone formation.@*Conclusions@#Home-made TMJ prostheses were stable after primary clinical application, but the long-term results need to be observed.
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Objective To investigated the etiologic characteristics of Shigella (S.) sonnei strains causing outbreaks and sporadic cases in some areas of Guangdong province and Guangxi Zhuang Autonomous Region during 2014-2016. Methods Fourteen S. sonnei strains isolated from outbreaks and 6 S. sonnei strains from sporadic cases from Guangdong and Liuzhou of Guangxi Zhuang Autonomous Region were tested for antimicrobial resistance and analyzed by pulsed-field gel electrophoresis (PFGE). Six typical strains were selected for whole genome sequencing typing and compared with 51 strains isolated both at home and abroad from NCBI genome database. Results The antibiotic resistance test indicated the isolates had high resistance rate to ampicillin, tetracycline, gentamicin, trimethoprim/sulfamethoxazole and nalidixic acid, while sensitive to azithromycin, chloromycetin and imipenem. PFGE showed high similarity (93.2%) among the strains isolated from different areas. The whole genome sequencing analysis also revealed that all the typical strains wereclustered into a same evolution branch, close to some strains from Korea. Conclusions The S. sonnei strains isolated from some areas of Guangdong and Guangxi Zhuang Autonomous Region showed high resistance to commonly used antibiotics, but they were sensitive to azithromycin, chloramphenicol and imipenem. The isolates in this study also showed similar PFGE patterns and close phylogenic evolution.
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Objective To understand the effect ofserotyping on Salmonella isolates,by use of Microsphere-based Liquid Array method,among diarrhea patients,in Guangdong.Methods Salmonella isolated from humans in Guangdong province were serotyped on the Microsphere-based Liquid Array platform with SSA kit.Results A total of 4 942 Salmonella strains with 189 serotypes,were identified in Guangdong province in 2010-2014.The top 100 serotypes accounted for 98.08％ (4 847/4 942) of all the strains.98％ of the top 100 species serotypes could completely be serotyped with SSA kit.In order to detect O antigen among 198 isolates with SSA kit,181 strains were carrying the O antigen,with the coincidence rate as 100％.However,under the SSA,98.32％ (528/537) of the H antigen could be detected and were consistent with the traditional serum agglutination test.The coincidence rate of fljB gene was 93.09％ (175/188),with false negative rate and false positive rate of fljB gene as 7.35％ (9/134) and 7.41％ (4/54) respectively.The coincidence rate of sdf gene and Vi gene were 100％.11 out of the 12 Salmonella strains could not be serotyped under the traditional methods but were successfully serotyped by the molecular serotyping method.Conclusions Using the SSA kit,more than 96％ of the anthropogenic Salmonella strains could be serotyped in Guangdong province.Comparing with the traditional methods,the coincidence rate of serotyping appeared over 98％.Under the Microsphere-based Liquid Array techniques,the molecular serotyping method appeared faster and more accurate on Salmonella serotyping than those traditional methods.
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Objective To prepare simulated stool specimens for proficiency testing ( PT) by mix-ing lentils with Salmonella, Shigella and Escherichia coli strains and to establish an assessment scheme for the detection of Salmonella and Shigella in clinical samples. Methods Salmonella, Shigella and Escherich-ia coli strains were respectively spiked to lentils in Cary-Blair transport medium to create simulated stool specimens. Various ratios of Escherichia coli to Salmonella strains were spiked to lentils to prepare mixed simulated stool specimens. The accuracy and stability of prepared stool samples for PT were tested in-house. Results of sample detection were collected from participating laboratories for further external quality assess-ment. Results The Escherichia coli and Salmonella strains mixed at ratios of 100 ∶ 1 to 106 ∶ 1 could be ef-ficiently isolated from the media. Enrichment was needed in order to effectively isolate Salmonella strains from the media when the ratios of Escherichia coli to Salmonella strains were 104 ∶ 1 to 106 ∶ 1. Of the16 participating laboratories, 14 laboratories (87. 5%) received a grade of“satisfactory” and the other 2 labo-ratories (12. 5%) received a grade of “mainly satisfactory”. Conclusion The simulated stool specimens and the PT procedures designed in this study were suitable for proficiency testing program on the detection of Salmonella, Shigella and other similar microbes.
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Objective To understand the effect ofserotyping on Salmonella isolates,by use of Microsphere-based Liquid Array method,among diarrhea patients,in Guangdong.Methods Salmonella isolated from humans in Guangdong province were serotyped on the Microsphere-based Liquid Array platform with SSA kit.Results A total of 4 942 Salmonella strains with 189 serotypes,were identified in Guangdong province in 2010-2014.The top 100 serotypes accounted for 98.08％ (4 847/4 942) of all the strains.98％ of the top 100 species serotypes could completely be serotyped with SSA kit.In order to detect O antigen among 198 isolates with SSA kit,181 strains were carrying the O antigen,with the coincidence rate as 100％.However,under the SSA,98.32％ (528/537) of the H antigen could be detected and were consistent with the traditional serum agglutination test.The coincidence rate of fljB gene was 93.09％ (175/188),with false negative rate and false positive rate of fljB gene as 7.35％ (9/134) and 7.41％ (4/54) respectively.The coincidence rate of sdf gene and Vi gene were 100％.11 out of the 12 Salmonella strains could not be serotyped under the traditional methods but were successfully serotyped by the molecular serotyping method.Conclusions Using the SSA kit,more than 96％ of the anthropogenic Salmonella strains could be serotyped in Guangdong province.Comparing with the traditional methods,the coincidence rate of serotyping appeared over 98％.Under the Microsphere-based Liquid Array techniques,the molecular serotyping method appeared faster and more accurate on Salmonella serotyping than those traditional methods.
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Objective To investigate the serotypes, antimicrobial resistance, virulence genes and molecular characteristics of food-borne Vibrio parahaemolytieus isolated in Guangdong province in 2014.Methods Sixty V.parahaemolyticus strains were tested in this study.The serotyping and antibiotic resistance test were conducted, while the tdh and trh gens of the strains were detected with conventional PCR, and pulsed field gel electrophoresis (PFGE) and multiple locus sequence typing (MLST) were conducted too.Results The 60 strains belonged to 13 serotypes, the major serotypes included O3 : K6, O4: K8, O 1 : K36 and O4: KUT.The antibiotic resistance test indicated the isolates were highly resistant to ampicillin (100.0％), sulfonamides (43.3％) and cefalotin (28.3％).Up to 56.7％(34/60) of the strains were resistant to two or more antibiotics, and 2 strains showed resistance to three antibiotics.The virulence gene detection indicated that 63.3％ (38/60) of the strains carded tdh+trh-, while only 1 strain carried tdh+trh+.The 60 strains digested by Not I belonged to 48 different PFGE patterns and 3 clusters.The cluster B included the strains isolated from sporadic food borne cases with serotype of O3:K6 and similarity of 62.6％-100.0％.The cluster C included O4:K8 strains with the PFGE pattem similarity of 56.7％-62.5％.The MLST indicated that the 60 strains had 26 sequence types (STs).The ST-3 was predominant, including 33 strains (serotypes O3:K6 and O1 : K36).The four O4:K8 strains formed another predominant colony, which was different from ST-3.Conclusion The etiologic characteristics of V.parahaemolyticus varied, which might be one of the reasons for high incidence of food-bome V.parahaemolyticus infection in Guangdong.The molecular characteristics of O4: K8 strain were differem from the other predominant serotypes.Close attention should be paid to the possible outbreak caused by O4: K8 strain in this area.
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[ABSTRACT]AIM:ToinvestigatetheeffectofmiR-155-specificsiRNAaloneorincombinationwithcytosinear-abinoside (Ara-C) on the growth and apoptosis of Burkitt lymphoma Raji cells .METHODS: miR-155-specific siRNA and/or Ara-C were used to treat the cells .Quantitative real-time polymerase chain reaction was used to detect the expres-sion of miR-155.The growth of the cells was analyzed by CKK-8 assay.The cell apoptosis was determined by flow cytome-try.RESULTS:The miR-155 expression level of the cells transfected with miR-155 siRNA was significantly lower than that in the 2 control groups .Ara-C or miR-155 siRNA alone inhibited the growth of Raji cells in a dose-depend manner . miR-155 siRNA combined with Ara-C produced more inhibition of cell proliferation (P<0.05).After treatment for 48 h, the apoptotic rate of Raji cells in miR-155 siRNA+Ara-C group [(38.4 ±1.4)%] was higher than that in Ara-C group [(16.5 ±0.3)%] and miR-155 siRNA group [(14.6 ±0.3)%], with statistically significant difference (P<0.05). The expression of caspase-3 in Ara-C+miR-155 siRNA group was increased significantly as compared with Ara-C group and miR-155 siRNA group.CONCLUSION:miR-155-specific siRNA enhances the chemosensitivity of Raji cells to Ara-C by inducing apoptosis through the caspase-3 pathway .
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<p><b>OBJECTIVE</b>To analyze the etiologic characteristics of O1/O139 Vibrio cholerae in Guangdong province in 2009-2013.</p><p><b>METHODS</b>Isolates from cholera cases and from the environment surveillance points were investigated by serological typing, antibiotic susceptibility testings, toxic genes detection and molecular typing to analyze the similarities and differences of the identified species.</p><p><b>RESULTS</b>Totally, 190 isolations of O1/O139 V. cholerae were obtained from cholera cases (16 strains) and environmental samples (174 strains) in Guangdong province in 2009-2013. The sero-types would include Inaba (3 isolates), Ogawa (7 isolates) and O139 (6 isolates) in all the isolates from the cholera cases. Ten strains from the ctxA positive cases were detected by PCR. Two Ogawa strains carried incomplete CTXΦ phage. Results from the antibiotic susceptibility test indicated that 5 strains were absolutely sensitive to 11 antibiotic discs in vitro, while another 3 strains were simultaneously resistant to 4 antibiotic discs. Except for 2 stains, all the O139 strains from the environment were ctxA negative, detected by PCR. Incomplete CTXΦ phage was found in the Inaba (53 isolates), Ogawa (22 isolates) and O139 (2 isolates), respectively. Results from the antibiotic susceptibility test exhibited that 25 strains were resistant simultaneously to 4 and/or more antibiotic discs, especially the Inaba strains from the seafoods(13 isolates). 2 Inaba strains from seafood were simultaneously resistant to 7 antibiotic discs. Results from PFGE molecular typing indicated that the PFGE types digested by Not I expressed significant diversity. Inaba and O139 strains from cases were gathered in the same clusters, while the Ogawa strains from cases scattered in different clusters but no significant correlation among these strains were found. Our results suggested that a distant genetic relationship might exist between these two different sources strains.</p><p><b>CONCLUSION</b>Complex and diverse as the virulence genes and genetic characteristics and with the grim situation of multi-drug resistant strains, all seemed important to strengthen the surveillance programs on the variation of strain types and antibiotics resistance of O1/O139 V. cholerae in Guangdong province.</p>
Subject(s)
Humans , Bacterial Typing Techniques , China , Epidemiology , Cholera , Epidemiology , Microbiology , Drug Resistance, Multiple, Bacterial , Genes, Bacterial , Microbial Sensitivity Tests , Vibrio cholerae , Classification , VirulenceABSTRACT
Objective To understand the distribution and the characteristics on molecular typing of Salmonella (S.) typhimurium isolates gathered from the surveillance program and to construct the standard S.typhimurium databank in the laboratory through surveillance network PulseNet,in Guangdong province to improve the capability of detection on laboratory-based foodbome outbreaks.Methods With the application of standard pulse-field gel electrophoresis (PFGE) and multiple loci VNTR analysis (MLVA) including seven VNTRs loci protocols on PulseNet International Network,275 isolates of S.typhimurium from ten cities in Guangdong province were typed and their patterns analyzed.The molecular typing databank was constructed by BioNumerics.Results With S.typhimurium the most common serotypes,the average annual positive rate of Salmonella strains and S.typhimurium were 4.03％ and 1.38％ respectively.The positive rate and proportion presented a double-peak trend,appearing in May and September.The chromosomal DNA of S.typhimurium was digested with Xba Ⅰ restricted endonucleotidase and 124 PFGE patterns were observed after pulse-field gel electrophoresis,with the discrimination index (D) as 0.928 6.The patterns including more than three S.typhimurium isolates and were further digested with the second enzyme Bln Ⅰ to achieve 174 patterns,with the D value as 0.989 1.Under MLVA method,143 variant patterns were obtained,with the D value reaching 0.966 5.Data showed that the discriminatory ability of the MLVA typing method in S.typhimurium was superior to PFGE-Xba Ⅰ but equal to PFGE-Xba Ⅰ-Bln Ⅰ.In addition,when S.typhimurium strains were respectively analyzed by PFGE under double enzymes digestion and MLVA,the results appeared coincident and relative.Conclusion The variant patterns showed by the two molecular typing methods indicating a genetic diversity existed among the clinical S.typhimurium isolates in Guangdong province.Databank of S.typhimurium was constructed and could be used in laboratory surveillance programs.Under the characterization of analyzing similarity and evolution among S.typhimurium isolates,MLVA was suitable for cluster analysis on early detection of outbreaks caused by S.typhimurium.
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Objective To investigate the etiological characteristics of Streptococcus pyogenes that caused scarlet fever in different periods in Guangdong province.Methods 22 isolates from different periods were analyzed through emm typing,PCR detection for super antigen genes,antibiotic susceptibility test and pulsed-field gel electrophoresis (PFGE).Results All isolates were susceptible to cefotaxim,levofloxacin and penicillin.Streptococcus pyogenes isolated after the year 2000 were 100％ resistant to erythrocin and clindamycin,but the resistant rate for strains isolated before the year 2000 was 9.1％ (1/11).There were 3 emm types indentified from 22 isolates including emm12.0 (59.09％,13/22),emm6.0 (36.36％,8/22) and emm1.0 (4.55％,1/22),which were detected in the isolates from the year 1997 and 2011,from 1978 and 1986,and from 2008,respectively.The positive rates for speA,speB,speC,speF,speG,speH,smeZ,and ssa genes detected by PCR were 54.55％,100％,100％,100％,100％,54.55％,0％,and 86.36％ respectively.Among all strains,95.45％ of the isolates carried 6 superantigen genes simultaneously.Three clusters of 10 PFGE subtypes were identified in 22 isolates.Cluster Ⅰ consisted of all strains from 1997 and one strain from 2011.Cluster Ⅱ consisted of strains isolated from 1978 and 1986.Cluster Ⅲ consisted of nine strains from 2011 and one from 2008.Conclusion S.pyrogenes isolates in Guangdong province were susceptible to penicillin but resistant to erythrocin.emm 12.0 accounted for the majority of the three types and there was a high frequency of super antigen genes.