Accurate and timely diagnosis of prosthetic joint infection is essential to initiate early treatment and achieve a favorable outcome. In this study, we used a rabbit model to assess the feasibility of technetium-99m-l...Accurate and timely diagnosis of prosthetic joint infection is essential to initiate early treatment and achieve a favorable outcome. In this study, we used a rabbit model to assess the feasibility of technetium-99m-labeled annexin V for detecting prosthetic joint infection. Right knee arthroplasty was performed on 24 New Zealand rabbits. After surgery, methicillin-susceptible Staphylococcus aureus was intra-articularly injected to create a model of prosthetic joint infection （the infected group, n = 12）. Rabbits in the control group were injected with sterile saline （n= 12）. Seven and 21 days after surgery, technetium-99m-labeled annexin V imaging was per- formed in 6 rabbits of each group. Images were acquired 1 and 4 hours after injection of technetium-99m- labeled annexin V （150 MBq）. The operated-to-normal-knee activity ratios were calculated for quantitative ana- lysis. Seven days after surgery, increased technetium-99m-labeled annexin V uptake was observed in all cases. However, at 21 days a notable decrease was found in the control group, but not in the infected group. The operated-to-normal-knee activity ratios of the infected group were 1.84 ±0.29 in the early phase and 2.19 ±0.34 in the delay phase, both of which were significantly higher than those of the control group （P=0.03 and P=0.02）. The receiver operator characteristic curve analysis showed that the operated-to-normal-knee activity ratios of the delay phase at 21 days was the best indicator, with an accuracy of 80%. In conclusion, technetium- 99m-labeled annexin V imaging could effectively distinguish an infected prosthetic joint from an uninfected prosthetic joint in a rabbit model.展开更多
Objective:To look for secondary bacterial infections in bronchogenic carcinoma（BC<sub>A</sub>） with resistant organisms harboring bla genes considering the paucity of relevant studies.Methods: A total of...Objective:To look for secondary bacterial infections in bronchogenic carcinoma（BC<sub>A</sub>） with resistant organisms harboring bla genes considering the paucity of relevant studies.Methods: A total of 137 confirmed cases of BC<sub>A</sub> and 34 healthy volunteers were studied for the occurrence and prevalence of bla<sub>CTX-M</sub> and and bla<sub>AmpC</sub> harboring-enterobacteriaceae.A subset of these patients（n=69） was previously reported for the secondary infection with the Aspergillus species. Bronchoalveolar lavages（BAL） were subjected for bacterial and fungal cultures and the bacterial isolates were screened by multiplex PCRs for the presence of bla<sub>CTX-M</sub> and bla<sub>AmpC</sub>.The isolates were also screened for the association of insertion sequence（IS26） by PCR and characterized by RAPD for any clonal relatedness.Results:A total of 143 bacterial isolates were obtained from 137 BAL specimens of BC,patients.The Enterobacteriaceae-isolates were multidrug-resistant showing concomitant resistance to fluoroquinolones and aminoglycosides.Both bla<sub>CTX-M</sub> and bla<sub>AmpC</sub> of CIT family were detected in 77.4%and 27.4%isolates,respectively.Sequencing revealed the presence of bla<sub>CTX-M-15</sub> and bla<sub>CMY-6</sub>.Twenty one percent of the isolates were simultaneously harboring bla<sub>ampC</sub> and bla<sub>CTX-M-15</sub>.IS26 PCR and RAPD typing revealed the presence of diverse bacterial population but no predominant clone was identified.The present study also suggests strong association of aspergillosis with lung cancer and further strengthens the potential use of non-validated serological tests suggested earlier.Conclusions:We emphasize that all patients of bronchogenic carcinoma should also be screened for secondary bacterial infections,along with secondary fungal infections,so as to introduce early and specific antimicrobial therapy and to prevent unwanted deaths.展开更多
Progression of cells from G2 phase of the cell cycle to mitosis is a tightly regulated cellular process that requires activation of the Cdc2 kinase, which determines onset of mitosis in all eukaryotic cells. In both h...Progression of cells from G2 phase of the cell cycle to mitosis is a tightly regulated cellular process that requires activation of the Cdc2 kinase, which determines onset of mitosis in all eukaryotic cells. In both human and fission yeast (Schizosaccharomyces pombe) cells, the activity of Cdc2 is regulated in part by the phosphorylation status of tyrosine 15 (Tyr15) on Cdc2, which is phosphorylated by Wee1 kinase during late G2 and is rapidly dephosphorylated by the Cdc25 tyrosine phosphatase to trigger entry into mitosis. These Cdc2 regulators are the downstream targets of two well- characterized G2/M checkpoint pathways which prevent cells from entering mitosis when cellular DNA is damaged or when DNA replication is inhibited. Increasing evidence suggests that Cdc2 is also commonly targeted by viral proteins, which modulate host cell cycle machinery to benefit viral survival or replication. In this review, we describe the effect of viral protein R (Vpr) encoded by human immunodeficiency virus type 1 (HIV-1) on cell cycle G2/M regulation. Based on our current knowledge about this viral effect, we hypothesize that Vpr induces cell cycle G2 arrest through a mechanism that is to some extent different from the classic G2/M checkpoints. One the unique features distinguishing Vpr-induced G2 arrest from the classic checkpoints is the role of phosphatase 2A (PP2A) in Vpr-induced G2 arrest. Interestingly, PP2A is targeted by a number of other viral proteins including SV40 small T antigen, polyomavirus T antigen, HTLV Tax and adenovirus E4orf4. Thus an in-depth understanding of the molecular mechanisms underlying Vpr-induced G2 arrest will provide additional insights into the basic biology of cell cycle G2/M regulation and into the biological significance of this effect during host-pathogen interactions.展开更多
Objective To identify Mycobacterium marinum (M. marinum) inducing misdiagnosis and treatment failure. Methods The lesional specimen of patient with cutaneous M. marinum were cultivated on Lwenstein-Jensen medium. Th...Objective To identify Mycobacterium marinum (M. marinum) inducing misdiagnosis and treatment failure. Methods The lesional specimen of patient with cutaneous M. marinum were cultivated on Lwenstein-Jensen medium. The isolate was identified by biochemical tests and polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis of the hsp65 gene. Results Smooth and non-pigmented colonies were noted after incubation at 32 ℃ for 2 weeks. The isolate was acid-fast bacilli and confirmed as M. marinum by biochemical tests and PCR-RFLP. Conclusion For a correct diagnosis of cutaneous M. marinum infection, it is crucial for clinicians to have a high index of suspicion, obtain the history of exposure and trauma and understand growth characteristics of the organism. Compared with conventional biochemical techniques, PCR-RFLP analysis is a more rapid, accurate and reliable method for mycobacterial identification to species level.展开更多
CTX-M-producing bacteria are known as a resistant source against oxyimino-cephalosporin such as cefotaxime and ceftazidime;although laboratory diagnosis of this gene has not been properly defined. The aims of this stu...CTX-M-producing bacteria are known as a resistant source against oxyimino-cephalosporin such as cefotaxime and ceftazidime;although laboratory diagnosis of this gene has not been properly defined. The aims of this study are determining the rates of prevalence of CTX-M and CTX-M group 1 in the Escherichia coli (E. coli) obtained from urinary tract infections (UTI), and also determining their genetic relationship in the city of Sanandaj. In current study, 180 E. coli strains isolated from urinary tract infections were used. Sensitivity to common antibiotics was studied by the disc diffusion method. Phenotypic detection of isolated ESBL-producing starins was done by the combination disc test. CTX-M and CTX-M1 genes were detected using the PCR method and finally, the possible clonal relationship between isolates was determined using the REP-PCR method. 89 samples were ESBL-positive. The PCR assay used for detecting the CTX-M gene, showed that 48 samples out of 180 samples (26.66%) contained that gene;also among these 48 samples, 23 (12.77%) had CTX-M group 1. Based on the REP-PCR assay, 48 genotypes among 48 samples were CTX-M-positive. Results from the REP-PCR assay indicated that the clonal propagation theory of one epidemic strain of Escherichia coli is not apply, i.e. all CTX-M-producing species are not originated from one single strain and the gene is spread between different isolates. Therefore, hospitals and their employees must be more hygiene and, proper disposal of hospital waste can help to prevent the spread of different resistances.展开更多
Immunotherapy with Bacillus Calmette-Guérin (BCG) to treat non-muscle invasive bladder cancer has become an effective and superior alternative to chemotherapy. Intravesical treatment with BCG appears to be relati...Immunotherapy with Bacillus Calmette-Guérin (BCG) to treat non-muscle invasive bladder cancer has become an effective and superior alternative to chemotherapy. Intravesical treatment with BCG appears to be relatively safe;however, occasionally BCG infection complicates such treatment. In the present work we describe three patients in whom BCG infection occurred after intravesical BCG therapy. All patients had positive urine culture forMycobacterium tuberculosis complex, using AccuProbe culture identification and then Genotype Mycobacterium MTBC test identified Mycobacterium bovis BCG. The diagnosis is difficult and microbiologic study is usually negative, so high index of suspicion is essential.展开更多
基金supported by the Chinese National Nature Sciences Foundation(31070861,81171745)
文摘Accurate and timely diagnosis of prosthetic joint infection is essential to initiate early treatment and achieve a favorable outcome. In this study, we used a rabbit model to assess the feasibility of technetium-99m-labeled annexin V for detecting prosthetic joint infection. Right knee arthroplasty was performed on 24 New Zealand rabbits. After surgery, methicillin-susceptible Staphylococcus aureus was intra-articularly injected to create a model of prosthetic joint infection （the infected group, n = 12）. Rabbits in the control group were injected with sterile saline （n= 12）. Seven and 21 days after surgery, technetium-99m-labeled annexin V imaging was per- formed in 6 rabbits of each group. Images were acquired 1 and 4 hours after injection of technetium-99m- labeled annexin V （150 MBq）. The operated-to-normal-knee activity ratios were calculated for quantitative ana- lysis. Seven days after surgery, increased technetium-99m-labeled annexin V uptake was observed in all cases. However, at 21 days a notable decrease was found in the control group, but not in the infected group. The operated-to-normal-knee activity ratios of the infected group were 1.84 ±0.29 in the early phase and 2.19 ±0.34 in the delay phase, both of which were significantly higher than those of the control group （P=0.03 and P=0.02）. The receiver operator characteristic curve analysis showed that the operated-to-normal-knee activity ratios of the delay phase at 21 days was the best indicator, with an accuracy of 80%. In conclusion, technetium- 99m-labeled annexin V imaging could effectively distinguish an infected prosthetic joint from an uninfected prosthetic joint in a rabbit model.
基金Department of Science & Technology,Ministry of Science & Technology,Government of India for awarding "Young Scientist Project Award"(FT/SR-L-111/2006)
文摘Objective:To look for secondary bacterial infections in bronchogenic carcinoma（BC<sub>A</sub>） with resistant organisms harboring bla genes considering the paucity of relevant studies.Methods: A total of 137 confirmed cases of BC<sub>A</sub> and 34 healthy volunteers were studied for the occurrence and prevalence of bla<sub>CTX-M</sub> and and bla<sub>AmpC</sub> harboring-enterobacteriaceae.A subset of these patients（n=69） was previously reported for the secondary infection with the Aspergillus species. Bronchoalveolar lavages（BAL） were subjected for bacterial and fungal cultures and the bacterial isolates were screened by multiplex PCRs for the presence of bla<sub>CTX-M</sub> and bla<sub>AmpC</sub>.The isolates were also screened for the association of insertion sequence（IS26） by PCR and characterized by RAPD for any clonal relatedness.Results:A total of 143 bacterial isolates were obtained from 137 BAL specimens of BC,patients.The Enterobacteriaceae-isolates were multidrug-resistant showing concomitant resistance to fluoroquinolones and aminoglycosides.Both bla<sub>CTX-M</sub> and bla<sub>AmpC</sub> of CIT family were detected in 77.4%and 27.4%isolates,respectively.Sequencing revealed the presence of bla<sub>CTX-M-15</sub> and bla<sub>CMY-6</sub>.Twenty one percent of the isolates were simultaneously harboring bla<sub>ampC</sub> and bla<sub>CTX-M-15</sub>.IS26 PCR and RAPD typing revealed the presence of diverse bacterial population but no predominant clone was identified.The present study also suggests strong association of aspergillosis with lung cancer and further strengthens the potential use of non-validated serological tests suggested earlier.Conclusions:We emphasize that all patients of bronchogenic carcinoma should also be screened for secondary bacterial infections,along with secondary fungal infections,so as to introduce early and specific antimicrobial therapy and to prevent unwanted deaths.
基金supported in part by grants from the National Institute of Health GM89630 and AI63080an endowed Research Scholar Chair by the Medical Research Institute Councilby an internal grant of the University of Maryland Medical Center(RYZ).
文摘Progression of cells from G2 phase of the cell cycle to mitosis is a tightly regulated cellular process that requires activation of the Cdc2 kinase, which determines onset of mitosis in all eukaryotic cells. In both human and fission yeast (Schizosaccharomyces pombe) cells, the activity of Cdc2 is regulated in part by the phosphorylation status of tyrosine 15 (Tyr15) on Cdc2, which is phosphorylated by Wee1 kinase during late G2 and is rapidly dephosphorylated by the Cdc25 tyrosine phosphatase to trigger entry into mitosis. These Cdc2 regulators are the downstream targets of two well- characterized G2/M checkpoint pathways which prevent cells from entering mitosis when cellular DNA is damaged or when DNA replication is inhibited. Increasing evidence suggests that Cdc2 is also commonly targeted by viral proteins, which modulate host cell cycle machinery to benefit viral survival or replication. In this review, we describe the effect of viral protein R (Vpr) encoded by human immunodeficiency virus type 1 (HIV-1) on cell cycle G2/M regulation. Based on our current knowledge about this viral effect, we hypothesize that Vpr induces cell cycle G2 arrest through a mechanism that is to some extent different from the classic G2/M checkpoints. One the unique features distinguishing Vpr-induced G2 arrest from the classic checkpoints is the role of phosphatase 2A (PP2A) in Vpr-induced G2 arrest. Interestingly, PP2A is targeted by a number of other viral proteins including SV40 small T antigen, polyomavirus T antigen, HTLV Tax and adenovirus E4orf4. Thus an in-depth understanding of the molecular mechanisms underlying Vpr-induced G2 arrest will provide additional insights into the basic biology of cell cycle G2/M regulation and into the biological significance of this effect during host-pathogen interactions.
文摘Objective To identify Mycobacterium marinum (M. marinum) inducing misdiagnosis and treatment failure. Methods The lesional specimen of patient with cutaneous M. marinum were cultivated on Lwenstein-Jensen medium. The isolate was identified by biochemical tests and polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis of the hsp65 gene. Results Smooth and non-pigmented colonies were noted after incubation at 32 ℃ for 2 weeks. The isolate was acid-fast bacilli and confirmed as M. marinum by biochemical tests and PCR-RFLP. Conclusion For a correct diagnosis of cutaneous M. marinum infection, it is crucial for clinicians to have a high index of suspicion, obtain the history of exposure and trauma and understand growth characteristics of the organism. Compared with conventional biochemical techniques, PCR-RFLP analysis is a more rapid, accurate and reliable method for mycobacterial identification to species level.
文摘CTX-M-producing bacteria are known as a resistant source against oxyimino-cephalosporin such as cefotaxime and ceftazidime;although laboratory diagnosis of this gene has not been properly defined. The aims of this study are determining the rates of prevalence of CTX-M and CTX-M group 1 in the Escherichia coli (E. coli) obtained from urinary tract infections (UTI), and also determining their genetic relationship in the city of Sanandaj. In current study, 180 E. coli strains isolated from urinary tract infections were used. Sensitivity to common antibiotics was studied by the disc diffusion method. Phenotypic detection of isolated ESBL-producing starins was done by the combination disc test. CTX-M and CTX-M1 genes were detected using the PCR method and finally, the possible clonal relationship between isolates was determined using the REP-PCR method. 89 samples were ESBL-positive. The PCR assay used for detecting the CTX-M gene, showed that 48 samples out of 180 samples (26.66%) contained that gene;also among these 48 samples, 23 (12.77%) had CTX-M group 1. Based on the REP-PCR assay, 48 genotypes among 48 samples were CTX-M-positive. Results from the REP-PCR assay indicated that the clonal propagation theory of one epidemic strain of Escherichia coli is not apply, i.e. all CTX-M-producing species are not originated from one single strain and the gene is spread between different isolates. Therefore, hospitals and their employees must be more hygiene and, proper disposal of hospital waste can help to prevent the spread of different resistances.
文摘Immunotherapy with Bacillus Calmette-Guérin (BCG) to treat non-muscle invasive bladder cancer has become an effective and superior alternative to chemotherapy. Intravesical treatment with BCG appears to be relatively safe;however, occasionally BCG infection complicates such treatment. In the present work we describe three patients in whom BCG infection occurred after intravesical BCG therapy. All patients had positive urine culture forMycobacterium tuberculosis complex, using AccuProbe culture identification and then Genotype Mycobacterium MTBC test identified Mycobacterium bovis BCG. The diagnosis is difficult and microbiologic study is usually negative, so high index of suspicion is essential.
