Objective To explore the interaction of Anxa2 with P-Glycoprotein （P-gp） in the migration and invasion of the multidrug-resistant （MDR） human breast cancer cell line MCF-7/ADR. Methods A pair of short hairpin RNA ...Objective To explore the interaction of Anxa2 with P-Glycoprotein （P-gp） in the migration and invasion of the multidrug-resistant （MDR） human breast cancer cell line MCF-7/ADR. Methods A pair of short hairpin RNA （shRNA） targeting P-gp was transfected into MCF-7/ADR cells, and monoclonal cell strains were screened. The expression of P-gp was detected by Western blot. Transwell chambers were used to observe the cell migration capacity and invasion ability. The interaction between P-gp and Anxa2 was examined by immunoprecipitation and immunofluorescence confocal microscopy analyses. Results P-gp expression was significantly knocked down, and there were notable decreasing trends in the migration and invasion capability of MDR breast cancer cells （P〈0.05）. There was a close interaction between Anxa2 and P-gp. Conclusions MCF-7/ADR is an MDR human breast cancer cell line with high migration and invasion abilities. The knockdown of P-gp notably impaired the migration and invasion abilities of the tumor cells. The interaction of Anxa2 with P-pg may play an important role in time enhanced invasiveness of MDR human breast cancer cells.展开更多
Enterococcus faecalis isolates （87） were phenotypically and genotypically identified and subsequently subjected to the antagonism test and antimicrobial susceptibility. The lipolitic, hemolytic and DNAse activities ...Enterococcus faecalis isolates （87） were phenotypically and genotypically identified and subsequently subjected to the antagonism test and antimicrobial susceptibility. The lipolitic, hemolytic and DNAse activities were identified along with the genes gelE, cylL, cylS, ccf, cpd and cob that, encode virulence determinants. Thirty seven percent of isolates inhibited Listeria monocytogenes （CERELA）, Listeria innocuous （CERELA）, Staphylococcus aureus （ATCC25932）, Lactococcus lactis （IL1403）, Micrococcus luteus （ATCC 10240） and Enterococcusfaecalis （ATCC29212）. All strains were sensitive to the ampicillin antibiotic, but 47% were resistant to at least one antimicrobial agent and 6% of isolates presented multidrug resistance. Ninety seven percent of isolates contained the gelE gene, but 77% of these isolates showed gelatinase activity. Presence of cylL and cylS genes was observed in 25% of the isolates, but only 5% presented hemolytic activity. None isolates showed lipase and DNAse activities. Eight percent of isolates contained the ccf gene and 2% showed the presence of the cpd and cob genes. The ability to inhibit pathogenic bacteria, low resistance to antibiotics and absence of virulence factors make some of Enterococcusfaecalis strains characterized in the present study promising for exploitation in other applications such as probiotics in aquaculture.展开更多
Objective:To find out how to overcome resistance during multiple myeloma(MM) treatment through establishing a multidrug resistant human multiple myeloma cell line and investigating its biological features.Methods:The ...Objective:To find out how to overcome resistance during multiple myeloma(MM) treatment through establishing a multidrug resistant human multiple myeloma cell line and investigating its biological features.Methods:The parent cell line MOLP-2 was exposed to different concentrations of melphalan and a melphalan-resistant cell line MOLP-2/R was identified by continuous stepwise selection.The cell morphology and growth curves were examined.Protein levels of P-gp, MRP and FANCD2 monoubiquitination were checked by Western blotting.The IC50 of melphalan and resistance index(RI) were detected by MTT assay.Results:A melphalan-resistant cell line MOLP-2/R was finally identified.The RI of MOLP-2/R cells to melphalan was 6.03.Besides melphalan it was cross resistant to other chemotherapeutic agents, including ADM, CTX, DDP and VP-16.The multiplication time was postponed(P < 0.05).Studies showed that FANCD2 protein monoubiquitination was enhanced, but the levels of P-gp and MRP expressions in the MOLP-2/R cells were similar with the parent cells.Conclusion:MOLP-2/R cell line may serve as an ideal model for exploring the mechanism of MDR.Over-expression of FANCD2 protein monoubiquitination might contribute to acquired drug resistance in MOLP-2/R cell line.展开更多
To study the transition dynamics of resistant-type human immunodeficiency virus 1 （HIV-1） in highly active antiretroviral therapy （HAART） and the affect of neutral mutation in the evolution of HIV-1, a mathematica...To study the transition dynamics of resistant-type human immunodeficiency virus 1 （HIV-1） in highly active antiretroviral therapy （HAART） and the affect of neutral mutation in the evolution of HIV-1, a mathematical model is proposed when mutation occurs mainly during reproduction. The derived results show that the resistant-type will certainly colonize in patients once mutation occurs. Furthermore, a neutral mutation is closely related to the colonized pattern of resistant-type HIV-1 quasispecies and there are some changes in the pattern of transmission dynamics when mutation occurs mainly during reproduction or in the absence of reproduction, which may lead to significant strategies for predicting or checking HIV-1 drug resistance in HAART.展开更多
The emergence of antibiotic resistance in bacteria is a major public-health issue.Synthesis of efficient antibiotic-free material is very important for fighting bacterial infection-related diseases.Herein,red-carbon d...The emergence of antibiotic resistance in bacteria is a major public-health issue.Synthesis of efficient antibiotic-free material is very important for fighting bacterial infection-related diseases.Herein,red-carbon dots(R-CDs)with a broad range of spectral absorption(350–700 nm)from organic bactericides or intermediates were synthesized through a solvothermal route.The prepared R-CDs not only had intrinsic antibacterial activities,but also could kill multidrug-resistant bacteria(multidrug-resistant Acinetobacter baumannii(MRAB)and multidrug-resistant Staphylococcus aureus(MRSA))effectively by generating reactive oxygen species.Furthermore,R-CDs could eliminate and inhibit the formation of MRAB biofilms,while conferring few side effects on normal cells.A unique property of R-CDs was demonstrated upon in vivo treatment of antibiotic-sensitive MRABinduced infected wounds.These data suggested that this novel R-CDs-based strategy might enable the design of nextgeneration agents to fight drug-resistant bacteria.展开更多
基金supported by grants from the National Natural Science Foundation of China(No.81071731 and 81001188)the Changjiang Scholars and Innovative Research Team(No.IRT1076)the Tianjin Higher Education Science & Technology Fund Planning Project(No.20100120)
文摘Objective To explore the interaction of Anxa2 with P-Glycoprotein （P-gp） in the migration and invasion of the multidrug-resistant （MDR） human breast cancer cell line MCF-7/ADR. Methods A pair of short hairpin RNA （shRNA） targeting P-gp was transfected into MCF-7/ADR cells, and monoclonal cell strains were screened. The expression of P-gp was detected by Western blot. Transwell chambers were used to observe the cell migration capacity and invasion ability. The interaction between P-gp and Anxa2 was examined by immunoprecipitation and immunofluorescence confocal microscopy analyses. Results P-gp expression was significantly knocked down, and there were notable decreasing trends in the migration and invasion capability of MDR breast cancer cells （P〈0.05）. There was a close interaction between Anxa2 and P-gp. Conclusions MCF-7/ADR is an MDR human breast cancer cell line with high migration and invasion abilities. The knockdown of P-gp notably impaired the migration and invasion abilities of the tumor cells. The interaction of Anxa2 with P-pg may play an important role in time enhanced invasiveness of MDR human breast cancer cells.
文摘Enterococcus faecalis isolates （87） were phenotypically and genotypically identified and subsequently subjected to the antagonism test and antimicrobial susceptibility. The lipolitic, hemolytic and DNAse activities were identified along with the genes gelE, cylL, cylS, ccf, cpd and cob that, encode virulence determinants. Thirty seven percent of isolates inhibited Listeria monocytogenes （CERELA）, Listeria innocuous （CERELA）, Staphylococcus aureus （ATCC25932）, Lactococcus lactis （IL1403）, Micrococcus luteus （ATCC 10240） and Enterococcusfaecalis （ATCC29212）. All strains were sensitive to the ampicillin antibiotic, but 47% were resistant to at least one antimicrobial agent and 6% of isolates presented multidrug resistance. Ninety seven percent of isolates contained the gelE gene, but 77% of these isolates showed gelatinase activity. Presence of cylL and cylS genes was observed in 25% of the isolates, but only 5% presented hemolytic activity. None isolates showed lipase and DNAse activities. Eight percent of isolates contained the ccf gene and 2% showed the presence of the cpd and cob genes. The ability to inhibit pathogenic bacteria, low resistance to antibiotics and absence of virulence factors make some of Enterococcusfaecalis strains characterized in the present study promising for exploitation in other applications such as probiotics in aquaculture.
文摘Objective:To find out how to overcome resistance during multiple myeloma(MM) treatment through establishing a multidrug resistant human multiple myeloma cell line and investigating its biological features.Methods:The parent cell line MOLP-2 was exposed to different concentrations of melphalan and a melphalan-resistant cell line MOLP-2/R was identified by continuous stepwise selection.The cell morphology and growth curves were examined.Protein levels of P-gp, MRP and FANCD2 monoubiquitination were checked by Western blotting.The IC50 of melphalan and resistance index(RI) were detected by MTT assay.Results:A melphalan-resistant cell line MOLP-2/R was finally identified.The RI of MOLP-2/R cells to melphalan was 6.03.Besides melphalan it was cross resistant to other chemotherapeutic agents, including ADM, CTX, DDP and VP-16.The multiplication time was postponed(P < 0.05).Studies showed that FANCD2 protein monoubiquitination was enhanced, but the levels of P-gp and MRP expressions in the MOLP-2/R cells were similar with the parent cells.Conclusion:MOLP-2/R cell line may serve as an ideal model for exploring the mechanism of MDR.Over-expression of FANCD2 protein monoubiquitination might contribute to acquired drug resistance in MOLP-2/R cell line.
基金Acknowledgments This work is supported by the National Natural Science Fund of P. R. China （No. 11271369） and the Natural Science Foundation Project of CQ CSTC （2010BB5020）.
文摘To study the transition dynamics of resistant-type human immunodeficiency virus 1 （HIV-1） in highly active antiretroviral therapy （HAART） and the affect of neutral mutation in the evolution of HIV-1, a mathematical model is proposed when mutation occurs mainly during reproduction. The derived results show that the resistant-type will certainly colonize in patients once mutation occurs. Furthermore, a neutral mutation is closely related to the colonized pattern of resistant-type HIV-1 quasispecies and there are some changes in the pattern of transmission dynamics when mutation occurs mainly during reproduction or in the absence of reproduction, which may lead to significant strategies for predicting or checking HIV-1 drug resistance in HAART.
基金supported by the National Natural Science Foundation of China(NSFC,21925802,21878039,21808028,22022803 and 22078046)the NSFC-Liaoning United Fund(U1908202)the National Key Research and Development Plan(2018AAA0100301)。
文摘The emergence of antibiotic resistance in bacteria is a major public-health issue.Synthesis of efficient antibiotic-free material is very important for fighting bacterial infection-related diseases.Herein,red-carbon dots(R-CDs)with a broad range of spectral absorption(350–700 nm)from organic bactericides or intermediates were synthesized through a solvothermal route.The prepared R-CDs not only had intrinsic antibacterial activities,but also could kill multidrug-resistant bacteria(multidrug-resistant Acinetobacter baumannii(MRAB)and multidrug-resistant Staphylococcus aureus(MRSA))effectively by generating reactive oxygen species.Furthermore,R-CDs could eliminate and inhibit the formation of MRAB biofilms,while conferring few side effects on normal cells.A unique property of R-CDs was demonstrated upon in vivo treatment of antibiotic-sensitive MRABinduced infected wounds.These data suggested that this novel R-CDs-based strategy might enable the design of nextgeneration agents to fight drug-resistant bacteria.
