Objective:To investigate the antibiotic resistance genes inserted into class I and class 2integrons in Acinetobacler baumannii[A.baumannii)isolates obtained from nine different cities in Turkey.Methods:A collection of...Objective:To investigate the antibiotic resistance genes inserted into class I and class 2integrons in Acinetobacler baumannii[A.baumannii)isolates obtained from nine different cities in Turkey.Methods:A collection of 281 A.baumannii clinical isolates were collected from nine diferenl state hospitals in Turkey and were confirmed as A.baumannU by conventional biochemical,API testing and bla_(-OXA-51)specific PCR.The isolates were examined by PCR for existence of class I and2 integron gene cassettes.Results:They were characterized by antimicrobial susceptibility testing and the highest resistance rates were determined for piperacillin(90.03%),ciprofloxacin(87.54%),cefepime and trimethoprim/sulfamethoxazole(81.13%).The lowest resistance rates was for cefotaxime(3.55%).class 1 integrons were detected in 6.4%(18/281)of A.baumannii strains and no class 2 integron was detected.The gene casselles of class 1 inlegrons AacCI-AAC(3)l-aadAI,AacCI-aadA1,AAC(3)-I,AAC(3)-I-AAC(3)-I-aadA1,TEM-1.AAC(3)-I-aadA1-AAC(3)-I-AAC(3)-I,AAC(3)-I-AAC(3)-I-AAC(3)-I-aadA1,AAC(3)-I-aadA1,AAC(3)-I-AAC(3)-I,AAC(3)-I-aadA1-AAC(3)-I-aadA1,AAC(3)-I-AAC(3)-I-aadA1-AAC(3)-I-aadA1 were detected in eighteen strains.The aac genes family were most frequently found integrated into the class 1 inlegrons and it was followed by aadA genes and TEM-1 genes.Conclusions:This is an extensive study on the distribulion of class 1 integron among A.baumannii in Turkey.In addition to these,two new alleles were observed.Their percentage rates of similarity to other cassettes are 95%aadA1(TK A18)and 89%,aadA 1(ANKA3).展开更多
The class 1 integron and complex gene cassettes among different species of clinical isolates in northern China were characterized in this study. 383 clinical isolates were obtained from northern China, and class 1 int...The class 1 integron and complex gene cassettes among different species of clinical isolates in northern China were characterized in this study. 383 clinical isolates were obtained from northern China, and class 1 integrons containing gene cassettes widely distributed among gram negative clinical isolates was observed. We find that the class 1 integron showed positive correlation with multidrug resistance phenotype of gram negative bacteria. In addition, we find that isolates belonged to one species harbored different types of gene cassette arrays, while same types of gene cassette arrays were observed in different species of isolates. The diversity of gene cassette arrays among the isolates indicated the complexity of multidrug resistance in clinical isolates in northern China.展开更多
Pseudomonas aeruginosa is one of the leading nosocomial pathogens worldwide, and their infections are difficult to treat due to acquired resistance to many antibiotics. This study aimed to detect class 1 and 2 integro...Pseudomonas aeruginosa is one of the leading nosocomial pathogens worldwide, and their infections are difficult to treat due to acquired resistance to many antibiotics. This study aimed to detect class 1 and 2 integrons and antibiotic susceptibility of clinical isolates of P. aeruginosa. Two hundred and five P. aeruginosa strains were collected from the seven general state hospitals in Turkey. They were characterized by antimicrobial susceptibility testing, screened for class 1 and class 2 integrons, and evaluated for the association between antibiotic resistance phenotypes and the presence of integrons. intI gene was amplified in 10 isolates (4.87%) by PCR and in seven isolates of them (70%) were found different gene cassettes. The aadA gene integrated into the class 1 integrons was most frequently found and it was followed by aac genes and blaOXA family genes. Sequence analysis of variable regions of the class 1 integrons showed five gene cassette arrays;aadA1(99%), aac(3)-Id(82%)-orf-aac(3”)-Ia(99%), aac(3)-Ie(83%)-blaoxa10(100%)- aadA1 (100%), aadA6(99%, 100%), aac(6’)-I(97%)-orf-aadA2(99%). No class 2 integron was detected. This study is the first multicenter study for class 1 integrons and it indicates the low rate of presence of class 1 gene cassette in P. aeruginosa.展开更多
Class 1 integrons are vital mobile genetic elements involved in the environmental transmission of antibiotic resistance genes(ARGs).However,knowledge about the diversity and abundance of class 1 integrons and gene cas...Class 1 integrons are vital mobile genetic elements involved in the environmental transmission of antibiotic resistance genes(ARGs).However,knowledge about the diversity and abundance of class 1 integrons and gene cassettes during drinking water treatment and distribution is still limited.In this study,we aimed to uncover the prevalence of class 1 integrons in the drinking water treatment and distribution systems with the combination of culture-dependent and culture-independent methods.Further,we applied the nanopore sequencing method to characterize the diversity and arrangement of ARGs carried by class 1 integron-associated gene cassettes.A total of 42 isolates were inti-positive among the 208 strains isolated from drinking water,which tended to confer multi-drug resistance compared with intll-negative isolates.The absolute abundance of the intl1 average i.15×10^(9) copies/L in the source water and underwent the most significant reduction of over 99.9% after liquid chiorine disinfection.Furthermore,nanopore sequencing revealed that the class 1 integron-associated gene cassettes carried 51 subtypes of ARGs in drinking water,mainly conferring resistance to aminoglycosides and trimethoprim.The treatment processes,especially liquid chlorine disinfection,reduced most of the ARGs carried by gene cassettes,though some of the ARG subtypes persisted along the treatment and distribution ike aac(6)-Il,aadA,and dfrB2.The antibiotic resistance gene cassette array laac(6')-Ⅱ arr was most frequently detected,especially in the chlorinated water.This study underlined that drinking water was potential reservoir for integron-mediated ARGs transfer,indicating that the health risks of resistance gene cassettes in class 1 integrons deserved urgent attention.展开更多
BACKGROUND The upregulation of serpin family B member 5(SERPINB5)has been linked to the progression of rectal cancer.However,the specific roles and underlying mechanisms of SERPINB5 in rectal cancer are not fully unde...BACKGROUND The upregulation of serpin family B member 5(SERPINB5)has been linked to the progression of rectal cancer.However,the specific roles and underlying mechanisms of SERPINB5 in rectal cancer are not fully understood.AIM To investigate the roles and mechanisms of SERPINB5 in rectal cancer.METHODS SERPINB5 protein level in rectal cancer tissues and cell lines was measured through western blot analysis.SW480 cells were transfected with pcDNASERPINB5 or short-hairpin RNA targeting SERPINB5(sh-SERPINB5).Cell proliferation,invasion,and apoptosis were then evaluated.The interaction between SERPINB5 and heat shock protein 90 alpha class A member 1(HSP90AA1)was confirmed through a co-immunoprecipitation assay.Subsequently,pcDNAHSP90AA1 or sh-HSP90AA1 was transfected into SW480 cells,and cell progression was then detected.Moreover,rescue experiments were used to investigate the effect of the SERPINB5/HSP90AA1 axis on rectal cancer progression.Additionally,sh-SERPINB5-transfected SW480 cells were implanted into nude mice,and xenograft tumor growth was then evaluated.RESULTS SERPINB5 was prominently upregulated in rectal cancer tissues and cells.SERPINB5 overexpression increased SW480 cell proliferation and invasion while reducing apoptosis.In contrast,SERPINB5 knockdown had the opposite effects.Moreover,SERPINB5 could interact with HSP90AA1 and promote HSP90AA1 expression in SW480 cells.HSP90AA1 overexpression facilitated SW480 cell proliferation and invasion and restrained apoptosis.By contrast,HSP90AA1 knockdown suppressed cell progression.The upregulation of HSP90AA1 reversed the SERPINB5 silencing-mediated inhibition of SW480 cell progression.Additionally,SERPINB5 knockdown retarded the growth of rectal cancer tumors in vivo.CONCLUSION SERPINB5 knockdown inhibited rectal cancer cell proliferation and invasion and retarded xenograft tumor growth by inhibiting HSP90AA1 expression.展开更多
基金Supported by Recep Tayyip Erdogan University(Grant No.BAP2012.102.03.4.and BAP-2013.102.03.4)
文摘Objective:To investigate the antibiotic resistance genes inserted into class I and class 2integrons in Acinetobacler baumannii[A.baumannii)isolates obtained from nine different cities in Turkey.Methods:A collection of 281 A.baumannii clinical isolates were collected from nine diferenl state hospitals in Turkey and were confirmed as A.baumannU by conventional biochemical,API testing and bla_(-OXA-51)specific PCR.The isolates were examined by PCR for existence of class I and2 integron gene cassettes.Results:They were characterized by antimicrobial susceptibility testing and the highest resistance rates were determined for piperacillin(90.03%),ciprofloxacin(87.54%),cefepime and trimethoprim/sulfamethoxazole(81.13%).The lowest resistance rates was for cefotaxime(3.55%).class 1 integrons were detected in 6.4%(18/281)of A.baumannii strains and no class 2 integron was detected.The gene casselles of class 1 inlegrons AacCI-AAC(3)l-aadAI,AacCI-aadA1,AAC(3)-I,AAC(3)-I-AAC(3)-I-aadA1,TEM-1.AAC(3)-I-aadA1-AAC(3)-I-AAC(3)-I,AAC(3)-I-AAC(3)-I-AAC(3)-I-aadA1,AAC(3)-I-aadA1,AAC(3)-I-AAC(3)-I,AAC(3)-I-aadA1-AAC(3)-I-aadA1,AAC(3)-I-AAC(3)-I-aadA1-AAC(3)-I-aadA1 were detected in eighteen strains.The aac genes family were most frequently found integrated into the class 1 inlegrons and it was followed by aadA genes and TEM-1 genes.Conclusions:This is an extensive study on the distribulion of class 1 integron among A.baumannii in Turkey.In addition to these,two new alleles were observed.Their percentage rates of similarity to other cassettes are 95%aadA1(TK A18)and 89%,aadA 1(ANKA3).
基金supported by Twelfth Five-Year Mega Project of Research on The Prevention and Control of HIV/AIDS,Viral Hepatitis Infectious Diseases 2013ZX10004-217 from the Ministry of Science and Technology,People’s Republic of China,the Project Sponsored by the Young Scholar Scientific Research Foundation of China CDC(No.2013A101)General Program of State Key Laboratory for Infections Disease Prevention and Control(No.2012SKLID205)
文摘The class 1 integron and complex gene cassettes among different species of clinical isolates in northern China were characterized in this study. 383 clinical isolates were obtained from northern China, and class 1 integrons containing gene cassettes widely distributed among gram negative clinical isolates was observed. We find that the class 1 integron showed positive correlation with multidrug resistance phenotype of gram negative bacteria. In addition, we find that isolates belonged to one species harbored different types of gene cassette arrays, while same types of gene cassette arrays were observed in different species of isolates. The diversity of gene cassette arrays among the isolates indicated the complexity of multidrug resistance in clinical isolates in northern China.
基金supported by Recep Tayyip Erdogan University Research Fund Grants BAP-2013.102.03.12 and BAP-2013.102.03.13.
文摘Pseudomonas aeruginosa is one of the leading nosocomial pathogens worldwide, and their infections are difficult to treat due to acquired resistance to many antibiotics. This study aimed to detect class 1 and 2 integrons and antibiotic susceptibility of clinical isolates of P. aeruginosa. Two hundred and five P. aeruginosa strains were collected from the seven general state hospitals in Turkey. They were characterized by antimicrobial susceptibility testing, screened for class 1 and class 2 integrons, and evaluated for the association between antibiotic resistance phenotypes and the presence of integrons. intI gene was amplified in 10 isolates (4.87%) by PCR and in seven isolates of them (70%) were found different gene cassettes. The aadA gene integrated into the class 1 integrons was most frequently found and it was followed by aac genes and blaOXA family genes. Sequence analysis of variable regions of the class 1 integrons showed five gene cassette arrays;aadA1(99%), aac(3)-Id(82%)-orf-aac(3”)-Ia(99%), aac(3)-Ie(83%)-blaoxa10(100%)- aadA1 (100%), aadA6(99%, 100%), aac(6’)-I(97%)-orf-aadA2(99%). No class 2 integron was detected. This study is the first multicenter study for class 1 integrons and it indicates the low rate of presence of class 1 gene cassette in P. aeruginosa.
基金financially supported by the National Natural Science Foundation of China(Nos.52025102,52192682,and 52200057)the Jiangsu Funding Program for Excellent Postdoctoral Talent(China)(No.2022ZB35).
文摘Class 1 integrons are vital mobile genetic elements involved in the environmental transmission of antibiotic resistance genes(ARGs).However,knowledge about the diversity and abundance of class 1 integrons and gene cassettes during drinking water treatment and distribution is still limited.In this study,we aimed to uncover the prevalence of class 1 integrons in the drinking water treatment and distribution systems with the combination of culture-dependent and culture-independent methods.Further,we applied the nanopore sequencing method to characterize the diversity and arrangement of ARGs carried by class 1 integron-associated gene cassettes.A total of 42 isolates were inti-positive among the 208 strains isolated from drinking water,which tended to confer multi-drug resistance compared with intll-negative isolates.The absolute abundance of the intl1 average i.15×10^(9) copies/L in the source water and underwent the most significant reduction of over 99.9% after liquid chiorine disinfection.Furthermore,nanopore sequencing revealed that the class 1 integron-associated gene cassettes carried 51 subtypes of ARGs in drinking water,mainly conferring resistance to aminoglycosides and trimethoprim.The treatment processes,especially liquid chlorine disinfection,reduced most of the ARGs carried by gene cassettes,though some of the ARG subtypes persisted along the treatment and distribution ike aac(6)-Il,aadA,and dfrB2.The antibiotic resistance gene cassette array laac(6')-Ⅱ arr was most frequently detected,especially in the chlorinated water.This study underlined that drinking water was potential reservoir for integron-mediated ARGs transfer,indicating that the health risks of resistance gene cassettes in class 1 integrons deserved urgent attention.
基金Supported by the Medical Science Research Project Plan of the Hebei Provincial Health Commission,No.20210027.
文摘BACKGROUND The upregulation of serpin family B member 5(SERPINB5)has been linked to the progression of rectal cancer.However,the specific roles and underlying mechanisms of SERPINB5 in rectal cancer are not fully understood.AIM To investigate the roles and mechanisms of SERPINB5 in rectal cancer.METHODS SERPINB5 protein level in rectal cancer tissues and cell lines was measured through western blot analysis.SW480 cells were transfected with pcDNASERPINB5 or short-hairpin RNA targeting SERPINB5(sh-SERPINB5).Cell proliferation,invasion,and apoptosis were then evaluated.The interaction between SERPINB5 and heat shock protein 90 alpha class A member 1(HSP90AA1)was confirmed through a co-immunoprecipitation assay.Subsequently,pcDNAHSP90AA1 or sh-HSP90AA1 was transfected into SW480 cells,and cell progression was then detected.Moreover,rescue experiments were used to investigate the effect of the SERPINB5/HSP90AA1 axis on rectal cancer progression.Additionally,sh-SERPINB5-transfected SW480 cells were implanted into nude mice,and xenograft tumor growth was then evaluated.RESULTS SERPINB5 was prominently upregulated in rectal cancer tissues and cells.SERPINB5 overexpression increased SW480 cell proliferation and invasion while reducing apoptosis.In contrast,SERPINB5 knockdown had the opposite effects.Moreover,SERPINB5 could interact with HSP90AA1 and promote HSP90AA1 expression in SW480 cells.HSP90AA1 overexpression facilitated SW480 cell proliferation and invasion and restrained apoptosis.By contrast,HSP90AA1 knockdown suppressed cell progression.The upregulation of HSP90AA1 reversed the SERPINB5 silencing-mediated inhibition of SW480 cell progression.Additionally,SERPINB5 knockdown retarded the growth of rectal cancer tumors in vivo.CONCLUSION SERPINB5 knockdown inhibited rectal cancer cell proliferation and invasion and retarded xenograft tumor growth by inhibiting HSP90AA1 expression.
