BACKGROUND Pancreatic cancer(PC)is one of the most aggressive malignancies characterized by rapid progression and poor prognosis.The involvement of cancer stem cells(CSCs)and Octamer transcription factor 4(OCT4)in PC ...BACKGROUND Pancreatic cancer(PC)is one of the most aggressive malignancies characterized by rapid progression and poor prognosis.The involvement of cancer stem cells(CSCs)and Octamer transcription factor 4(OCT4)in PC pathobiology is being increasingly recognized.AIM To investigate the role of OCT4 in pancreatic CSCs and its effect on PC cell prolif-eration,migration,drug sensitivity,and stemness maintenance.METHODS We analyzed OCT4 and CD133 expression in PC tissues and cell lines.BxPC-3 cells were used to assess the effects of OCT4 modulation on cellular behavior.Proliferation,migration,and stemness of BxPC-3 cells were evaluated,and the PI3K/AKT/mTOR pathway was examined to gain mechanistic insights.RESULTS OCT4 and CD133 were significantly overexpressed in PC tissues.OCT4 mo-dulation altered BxPC-3 cell proliferation,invasion,and stemness,with OCT4 overexpression(OV-OCT4)enhancing these properties and OCT4 interference decreasing them.OV-OCT4 activated the PI3K/AKT/mTOR pathway,which correlated with an increase in PC stem cells(PCSC).CONCLUSION OCT4 plays a crucial role in PCSCs by influencing the aggressiveness and drug resistance of PC cells,thus presenting itself as a potential therapeutic target.展开更多
Objective: To investigate the prevalence of myco-plasma infections and the sensitivity to antibiotics among patients with nongonococcal urethritis or cer-vicitis (NGU) in Chongqing. Methods: 387 NGU cases with mycopla...Objective: To investigate the prevalence of myco-plasma infections and the sensitivity to antibiotics among patients with nongonococcal urethritis or cer-vicitis (NGU) in Chongqing. Methods: 387 NGU cases with mycoplasma-positive results upon culture were analysed retrospectively. RESULTS: The majority of patients with mycoplasma infections were in the 20-40 year old age group. No significant difference was found between males and females. Ureaplasma urealyticum is the main pathogen of these NGU cases and no clear relationship between its concentration and pathogenic ability was noted. Drug sensitivity was tested against nine antibiotics; the sensitivity rates to josamycim, minocycline and doxycycline were 94.06%, 88.89% and 86.82% respectively, while the resistance rates to lincomycin, ofloxacin, azithromycin and roxthromycin were 74.94%, 42.12%, 41.60% and 40.31% in turn. Conclusions: Josamycin, minocycline and doxycycline could be used as the first choice to treat NGU with mycoplasma infections in Chongqing. It is important to select antibiotics for NGU treatment with mycoplasma infections based on the results of drug sensitivity tests.展开更多
AIM:To construct Hsp90 antisense RNA eukaryotic expression vector, transfect it into SGC7901 and SGC7901/VCR of MDR-type human gastric cancer cell lines, HCC7402 of human hepatic cancer and Ec109 of human esophageal c...AIM:To construct Hsp90 antisense RNA eukaryotic expression vector, transfect it into SGC7901 and SGC7901/VCR of MDR-type human gastric cancer cell lines, HCC7402 of human hepatic cancer and Ec109 of human esophageal cancer cell lines, and to study the cell cycle distribution of the gene transected cells and their response to chemotherapeutic drugs.METHODS:A 1.03kb cDNA sequence of Hsp90beta was obtained from the primary plasmid phHSP90 by EcoR I and BamH I nuclease digestion and was cloned to the EcoR I and BamH I site of the pcDNA by T4DNA ligase and an antisense orientation of Hsp90beta expression vector was constructed. The constructs were transfected with lipofectamine and positive clones were selected with G418. The expression of RNA was determined with dot blotting and RNase protection assay, and the expression of Hsp90 protein determined with western blot. Cell cycle distribution of the transfectants was analyzed with flow cytometry, and the drug sensitivity of the transfectants to Adriamycin (ADR), vincrinstine (VCR), mitomycin (MMC) and cyclophosphamide (CTX) with MTT and intracellular drug concentration of the transfectants was determined with flow cytometry.RESULTS:In EcoR I and BamH I restriction analysis, the size and the direction of the cloned sequence of Hsp90beta remained what had been designed and the gene constructs were named pcDNA-Hsp90.AH-SGC7901, AH-SGC7901/VCR, AH-HCC7402 and AH-Ec109 cell clones all expressed Hsp90 anti-sense RNA. The expression of Hsp90 was down-regulated in AH-SGC7901, AH-SGC7901/VCR, AH-HCC7402 and AH-Ec109 cell clones. Cell cycle distribution was changed differently. In AH-SGC7901/VCR and AH-Ec109 cells, G(1) phase cells were increased; S phase and G(2) phase cells were decreased as compared with their parental cell lines. In AH-SGC7901 cell, G(1)phase cells were decreased, G(2) phase cells increased and S phase cells were not changed, and in AH-HCC7402 cells G(1), S and G(2) phase cells remained unchanged as compared with their parental cell lines. The sensitivity of AH-SGC7901, AH-SGC7901/VCR, AH-HCC7402 and AH-Ec109 to chemotherapeutic drugs, the sensitivity of AH-SGC7901/VCR to ADR, VCR, MMC and CTX the sensitivity of AH-HCC7402 to ADR and VCR, and the sensitivity of Ec109 to ADR, VCR and CTX all increased as compared with their parental cell lines. The mean fluorescence intensity of ADR in AH-SGC7901, AH-SGC7901/VCR, AH-HCC7402 and AH-Ec109 was also significantly elevated (P 【 0.05).CONCLUSION: Down-regulation of Hsp90 could change cell cycle distribution and increase the drug sensitivity of tumor cells.展开更多
AIM: To study the effect of a number of chemotherapeutic drugs on five human intrahepatic cholangiocarcinoma (CCA) cell lines. The expressions of genes that have been proposed to influence the resistance of chemothera...AIM: To study the effect of a number of chemotherapeutic drugs on five human intrahepatic cholangiocarcinoma (CCA) cell lines. The expressions of genes that have been proposed to influence the resistance of chemotherapeutic drugs including thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), glutathione-S-transferase PI (GSTP1), multidrug resistance protein (MDR1) and multidrug resistance-associated proteins (MRPs) were also determined. METHODS: Five human CCA cell lines (KKU-100, KKU-M055, KKU-M156, KKU-M214 and KKU-OCA17) were treated with various chemotherapeutic drugs and growth inhibition was determined by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. Semi-quantitative levels of gene expression were determined by a reverse transcriptase polymerase chain reaction (RT-PCR). Results of IC_(50) values and the ratios of gene expression were analyzed by linear regression to predict their relationship. RESULTS: Among five CCA cell lines, KKU-M055 was the most sensitive cell line towards all chemotherapeutic drugs investigated, particularly taxane derivatives with IC_(50) values of 0.02-3 nmol/L, whereas KKU-100 was apparently the least sensitive cell line. When compared to other chemotherapeutic agents, doxorubicin and pirarubicin showed the lowest IC_(50) values (＜5 μmol/L) in all five CCA cell lines. Results from RT-PCR showed that TS, MRP1, MRP3 and GSTP1 were highly expressed in these five CCA cell lines while DPD and MRP2 were only moderately expressed. It should be noted that MDR1 expression was detected only in KKU-OCA17 cell lines. A strong correlation was only found between the level of MRP3 expression and the IC_(50) values of etoposide, doxorubicin and pirarubicin (r=0.86-0.98, P＜0.05). CONCLUSION: Sensitivity to chemotherapeutic agents is not associated with the histological type of CCA. Choosing of the appropriate chemotherapeutic regimen for the treatment of CCA requires knowledge of drug sensitivity. MRP3 was correlated with resistance of CCA cell lines to etoposide, doxorubicin and pirarubicin, whereas other chemotherapeutic drugs showed no association. The role of this multidrug resistance-associated protein, MRP3, in chemotherapeutic resistance in CCA patients needs to be further investigated.展开更多
Objective： Survivin is one of the apoptosis inhibitor genes and is rarely expressed in adult tissues. However, survivin expression has been detected in various human cancers and correlations have been recognized betw...Objective： Survivin is one of the apoptosis inhibitor genes and is rarely expressed in adult tissues. However, survivin expression has been detected in various human cancers and correlations have been recognized between the level of expression of this gene in tumors and prognosis. In this study, we investigated the effect of Survivin-siRNA on the drug sensitivity of osteosarcoma cell line MG-63. Methods： Two siRNAs （Survivin-siRNA1, Survivin-siRNA2） specifically targeting Survivin gene were chemically synthesized and transfected into MG-63 ceils. The Survivin mRNA level was detected by reverse transcription-polymerase chain reaction （RT-PCR）. The survivin protein expression and cell apoptosis rate were analyzed by flow cytometry （FCM）. The 50% inhibition concentration （IC50） of cisplatin （DDP） and adriamycin （ADM） on MG-63 cells was determined by MTT method. Results： Two short siRNA targeting survivin down-regulated the transcription of survivin gene dramatically and elevated apoptosis rate. They increased the drug sensitivity of MG-63 cells to ADM by five-fold and to DDP by nine-fold. Conclusion： Validated Survivin specific siRNA can effectively inhibit Survivin expression in survivin-overexpressing osteosarcoma MG-63 cell line and enhance the drug sensitivity of MG-63 cell line to ADM and DDP. Short survivin-siRNA mediated gene silencing may be a useful therapeutic strategy for osteosarcoma. These results suggest that survivin might be helpful for diagnosis of osteosarcoma and survivin siRNA combined with adriamycin or cisplatin may be a feasible strategy to enhance the effects of chemotherapy in patients with osteosarcoma.展开更多
Ten pathogenic strains were isolated fi-om gingers infected by blast, and were identified by substrate utilization test and biochemical test. The identifica- tion results showed that these ten strains accorded with th...Ten pathogenic strains were isolated fi-om gingers infected by blast, and were identified by substrate utilization test and biochemical test. The identifica- tion results showed that these ten strains accorded with the basic characteristics of Pseudomonas solanacearum. Drug sensitivity test of ten strains was carried out, and prevention agents were screened to provide an experimental basis for the control of ginger blast.展开更多
[ Objectives] The paper aimed to select drugs reasonably for treatment of rex rabbit colibacillosis, and to isolate the pathogenicity of Escherichia coll. [ Methods ] Pathogen isolation, drug sensitivity test and path...[ Objectives] The paper aimed to select drugs reasonably for treatment of rex rabbit colibacillosis, and to isolate the pathogenicity of Escherichia coll. [ Methods ] Pathogen isolation, drug sensitivity test and pathogen regression test were performed with rex rabbits killed by E. coli in clinic. [ Results] The isolate was E. coli 0-23, susceptible to amikacin and cefotaxime sodium; when the challenge dose was 1.0 mL/rabbit （about one billion E. coli）, the test animal would discharge mucous feces. [ Conclusions] The results provided model support for clinical medicine selection against rex rabbit colibacillosis.展开更多
[Objectives] The study aimed to identify the pathogen that causes diarrhea in minks. [Methods] Liver tissues were aseptically collected from dead minks with diarrhea. By bacterial isolation and culture,morphological o...[Objectives] The study aimed to identify the pathogen that causes diarrhea in minks. [Methods] Liver tissues were aseptically collected from dead minks with diarrhea. By bacterial isolation and culture,morphological observation,biochemical test and pathogenicity test,the isolated strain was identified as pathogenic E. coli. [Results]The pathogen causing diarrhea in minks was confirmed as a pathogenic E. coli strain. Drug sensitivity test indicated that the isolated pathogenic E. coli strain was highly sensitive to ceftazidime,cefotaxime,enrofloxacin,florfenicol and cephradine,moderately sensitive to ampicillin,ciprofloxacin,amikacin,doxycycline,lincomycin and gentamycin,and resistant to amoxycillin,neomycin,spectinomycin,polymyxin and penicillin. [Conclusions] This study provided reference for the prevention and control of abortion in female minks in Qinhuangdao region.展开更多
Purpose： Skin ulcer is a common type of disease affecting patients＇ health and quality of life, and bacterial infection increases the difficulty of its management. Methods： The present study collected the results o...Purpose： Skin ulcer is a common type of disease affecting patients＇ health and quality of life, and bacterial infection increases the difficulty of its management. Methods： The present study collected the results of bacterial culture sampled from the surface of 110 cases of skin ulcers at our hospital from January 2011 to December 2012. We analyzed the constituent ratios of ulcer surface bacteria, the change in the main infectious bacteria and the results of drugsensitivity testing for common bacteria. In addition, the characteristics of bacterial infection of skin ulcers were summarized. Result： Of the 110 samples, 90 isolated bacteria were cultured. Sixty-one were Gram-negative bacteria, mainly comprising Pseudomonas aeruginosa, Klebsiella pneumoniae, Enterobacter cloacae and Escherichia coli. In addition, 23 isolates were Gram-positive bacteria, mainly comprising Staphylococcus aureus and Enterococcus faecalis. The probability of a negative bacterial culture in 2012 was significantly lower than that in 2011 （16.7% vs. 40.0%, p 〈 0.01）. Moreover, the probability of P. aeruginosa infection in 2012 was significantly higher than that in 2011 （31.7% vs. 14.0%, p 〈 0.01）. P. aeruginosa was resistant to seven commonly used antibiotics. Both K. pneumoniae and E. coli had higher resistance to ampicillin. E. cloacae were not sensitive to piperacillin/tazobactam. Acinetobacter baumannii was resistant to all the tested drugs. S. aureus, E. faecalis and Staphylococcus epidermidis had high resistance to clindamycin. There was other drug resistance to reflect the higher rate of skin bacterial resistance. Conclusion： Skin bacterial resistance rate is high. Gram-negative bacteria gradually account for the majority, and P. aeruginosa becomes the most important skin infection pathogen. These characteristics of bacterial infections of skin ulcers provide a significant reference for guiding the selection of antibiotics, better controlling infections of skin ulcers and accelerating the healing of skin ulcers.展开更多
Background All-trans retinoic acid （ATRA） can influence the tumor cell proliferation cycle, and some chemotherapeutic drugs are cycle specific. In this study, we hypothesize that ATRA can enhance chemotherapeutic dr...Background All-trans retinoic acid （ATRA） can influence the tumor cell proliferation cycle, and some chemotherapeutic drugs are cycle specific. In this study, we hypothesize that ATRA can enhance chemotherapeutic drug sensitivity by affecting the cell cycle of tumor cells.Methods The cell cycle of LoVo cells was evaluated using flow cytometry （FCM）. Cell viability was analyzed using the MTT assay. The morphologic changes in the treated LoVo cells were measured with acridine orange （AO）/ethidium bromide （EB） staining. Expression of survivin in LoVo cells was analyzed by immunofluorescence assay.Results After LoVo cells were treated with ATRA, the G0/G1 ratio of the tumor cells increased and the cell ratio of S-and G2/M-phase decreased. Viability of the cells decreased significantly after combined treatment with ATRA and 5-fluorouracil （5-FU） or mitomycin c （MMC） and was evaluated by fluorescence microscopy. Expression level of survivin in the tumor cells decreased after ATRA combination treatment.Conclusions ATRA enhances drug sensitivity of the LoVo cell line to cell cycle-specific agents and inhibits the expression of survivin in LoVo cells. The combination of ATRA and 5-FU or MMC promoted cell apoptosis, and the mechanism involved in apoptosis may be related to inhibition of survivin gene expression.展开更多
Since taking part as leading actors in driving the metastatic process,circulating tumor cells(CTCs)have displayed a wide range of potential applications in the cancer-related research field.Besides their well-proved p...Since taking part as leading actors in driving the metastatic process,circulating tumor cells(CTCs)have displayed a wide range of potential applications in the cancer-related research field.Besides their well-proved prognostic value,the role of CTCs in both predictive and diagnostics terms might be extremely informative about cancer properties and therefore highly helpful in the clinical decision-making process.Unfortunately,CTCs are scarcely released in the blood circulation and their counts vary a lot among different types of cancer,therefore CTC detection and consequent characterization are still highly challenging.In this context,in vitro CTC cultures could potentially offer a great opportunity to expand the number of tumor cells isolated at different stages of the disease and thus simplify the analysis of their biological and molecular features,allowing a deeper comprehension of the nature of neoplastic diseases.The aim of this review is to highlight the main attempts to establish in vitro CTC cultures from patients harboring different tumor types in order to highlight how powerful this practice could be,especially in optimizing the therapeutic strategies available in clinical practice and potentially preventing or contrasting the development of treatment resistance.展开更多
In order to provide a sensitive cell line model for investigating the mechanisms underlying the lymphatic metastasis of tumors and the effect of medicine against cells,a new murine ascites hepatocarcinoma cell line wi...In order to provide a sensitive cell line model for investigating the mechanisms underlying the lymphatic metastasis of tumors and the effect of medicine against cells,a new murine ascites hepatocarcinoma cell line with high lymphatic metastatic potential(Hca-P/L_(6))was established and the effect of curcumin on biological behavior of Hca-P/L_(6) was observed.Murine ascites hepatocarcinoma cell strain with low lymphatic metastatic potential(Hca-P)was subcutaneously inoculated into the medioventral line of a mouse 615 and thefirst generation of metastatic tumor cells of inguinal lymph node(Hca-P/L_(1))was obtained.Then,Hca-P/L_(1) was screened by the route of mouse foot pad subcutaneously!lymph node!scale-up culture in vitro!mouse foot pad subcuta-neously forfive times consecutively.The sensitivity of two murine ascites hepatocarcinoma cell lines(Hca-P and Hca-P/L_(6))and two anchorage-dependent human hepato-carcinoma cell lines(SMC7721 and HepG_(2))to curcumin were studied by use of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay after these cells had been pretreated by curcumin at the concentration of 15–240μmol/L for 48 h.After pretreatment by curcumin at the maximum non-cytotoxic dose of 15μmol/L in vitro,the effect of curcumin against cell proliferation of Hca-P and Hca-P/L6 was observed by inverted micro-scope,cell growth curve and cell population doubling time;the effects of curcumin on cell cycles of Hca-P/L6 and Hca-P were studied byflow cytometry(FCM).The results showed Hca-P/L_(6) spreading to the lymph nodes at multiple sites in mice was screened from Hca-P.The lymph node metastatic rate was 100%.Curcumin had significant growth inhibiting effect on both murine ascites and human hepatocarcinoma cell lines in a dose-dependent manner(P<0.05).At concentrations of 30–120μmol/L,curcu-min had more inhibition on murine ascites hepatocarci-noma cell lines than on human anchorage-dependent hepatocarcinoma cell lines.At concentrations of 60–240μmol/L,curcumin had more inhibition on Hca-P/L_(6) with the 50%inhibitory concentration(IC50)of 51.48μmol/L than on Hca-P with IC50 of 90.87μmol/L.After pretreatment by curcumin at the maximum non-cytotoxic dose of 15 mol/L for 7 days,the proliferations of Hca-P/L_(6) and Hca-P were inhibited(P<0.05)in a time-dependent manner(P<0.01)and the population doubling time of Hca-P/L6 and Hca-P was prolonged(P<0.01),and curcumin had more inhibition on Hca-P/L6 than on Hca-P(P<0.05).After pretreatment by 15μmol/L curcumin for 48 h,the morphous of Hca-P/L_(6) was influenced more seriously than that of Hca-P and the cell cycle was redistributed with Hca-P/L6 being blocked in the S phase and Hca-P in the S and G_(2)/M phases.Hca-P/L_(6) was validated to be more sensitive to curcumin than Hca-P.Hca-P/L_(6) is a novel sensitive cell line model for investigating the mechanisms underlying tumor lymphatic metastasis and the effect of the medicine against cells.展开更多
OBJECTIVE To explore whether MDM2 transfection can alter the MDM2-p53 autoregulatory feedback loop so as to change the sensitivity of ovarian cancer cell lines to cisplatin. METHODS The ovarian cancer cell line A2780 ...OBJECTIVE To explore whether MDM2 transfection can alter the MDM2-p53 autoregulatory feedback loop so as to change the sensitivity of ovarian cancer cell lines to cisplatin. METHODS The ovarian cancer cell line A2780 expressing wild-type P53 and the ovarian cancer cell line SKOV-3 with the p53 null type were stably transfected with pCMV-MDM2 or pCMV as a control. The blocked expression of P53 was determined by Western blots. Cytotoxicity was assessed using the MTT assay and the trypan blue exclusion assay. Flow cytometry was used to detect changes in the cell cycle and removal of platinum -DNA adducts was measured by atomic absorption spec-troscopy. RESULTS (1) Parental A2780 and A2780-V cells (IC50= 15.14±1.39 μmol) have similar cisplatin sensitivities, whereas sensitivity to cisplatin in A2780-M cells (IC50=7.98±1.32 μmol) was 2 to 3 fold greater (P=0.001). The trypan blue exclusion assay demonstrated that cisplatin killed a higher percentage of A2780-M cells compared to A2780-V cells. There was no significant change following MDM2 transfection in SKOV-3 cells. (2) After cisplatin treatment, A2780-M cells showed a pronounced S-phase arrest, however, A2780 cells with the intact wild-type P53, arrested primarily at the G2/M transition. (3) Platinum uptake was similar for all of the A2780 cell lines after ciaplatin treatment, but the removal of plat-inum-DNA adducts was reduced in the A2780-M cells compared with A2780-V cells. CONCLUSION MDM2 increases cisplatin cytotoxicity in ovarian cancer cells by blocking the expression of p53 through the MDM2-p53 autoregulatory feedback loop.展开更多
[Objective] This study aimed to isolate and identify the drug-resistant Es- cherichia coli strains from chickens. [Method] E. coli strains were isolated from the fecal samples collected from five chicken farms around ...[Objective] This study aimed to isolate and identify the drug-resistant Es- cherichia coli strains from chickens. [Method] E. coli strains were isolated from the fecal samples collected from five chicken farms around Shangqiu City, and verified by biochemical and pathogenic assay. [Result] Among the 35 isolated E. coli stains, 11 E. coil stains were sensitive to florfenicol, amikacin, neomycin and gentamicin; 12 E. coli stains were moderately sensitive to ciprofloxacin, doxycycline and norfloxacin; 15 E. coil stains were resistant against erythromycin, penicillin and streptomycin. [Conclusion] Strengthening biosecurity measures, rationally using vaccine and choosing effective antibiotics are the most cost-efficient methods to control E. coli.展开更多
Objective： The aim of this study was to study the cisplatin sensitizing effect and mechanism of anti-HPV16 E6- ribozyme on cervical carcinoma cell line. Methods： The anti-HPV16E6-ribozyme and empty eucaryotic expres...Objective： The aim of this study was to study the cisplatin sensitizing effect and mechanism of anti-HPV16 E6- ribozyme on cervical carcinoma cell line. Methods： The anti-HPV16E6-ribozyme and empty eucaryotic expressing plasmids were transfected into CaSKi cell, which named as CaSKi-R, CaSKi-P respectively. E6 mRNA, the sensitivity to cisplatin, apoptosis rates, expression of p53, Bcl-2, Bax and C-myc proteins and mRNA were examined by Northem blot, MTT colorimetric assay, PI/Annexin V stained methods, flow cytometry anslysis and RT-PCR, respectively. Results： E6 mRNA was less in CaSKi-R than in CaSKi. The sensitivity of CaSKi-R cells to cisplatin was 2.28 and 2.21 times than that of CaSKi and CaSKi-P cells. The apoptotic rates in CaSKi, CaSKi-P and CaSKi-R cells was （18.9 ± 3.5）%, （19.7 ± 4.8）% and （40.4 ± 4.5）%. The apoptotic rates was increased in CaSKi-R than that of CaSKi cells treated with cisplatin （P = 0.003）. Comapred with CaSKi cell, the expression of p53 （P = 0.000）, Bax protein （P = 0.002） was significantly higher and the expression of Bcl-2 protein （P = 0.005）, C-myc protein （P = 0.005） was significantly lower in CaSKi-R than that of CaSKi cell treated with cisplatin. Comapred with CaSKi cell, the expression of p53, Bax mRNA in CaSKi-R cell treated with cisplatin increased, while Bcl-2, C-myc mRNA decreased. Conclusion： CaSKi-R cells transfected by anti-HPVE6-ribozyme increased the sensitivity to cisplatin. The increase of sensitivity to cisplatin in CaSKi-R cells may be associated with increasing expression of p53, Bax protein, and decreasing expression of C-myc, Bcl-2 proteins.展开更多
Emerging cohorts and basic studies have associated certain genetic modifications in cancer patients,such as gene mutation,amplification,or deletion,with the overall survival prognosis,underscoring patients’genetic ba...Emerging cohorts and basic studies have associated certain genetic modifications in cancer patients,such as gene mutation,amplification,or deletion,with the overall survival prognosis,underscoring patients’genetic background may directly regulate drug sensitivity/resistance during chemotherapies.Understanding the molecular mechanism underpinning drug sensitivity/resistance and further uncovering the effective drugs have been the major ambition in the cancer drug discovery.The emergence and popularity of CRISPR/Cas9 technology have reformed the entire life science research,providing a precise and simplified genome editing tool with unlimited editing possibilities.Furthermore,it presents a powerful tool in cancer drug discovery,which hopefully facilitates us with a rapid and reliable manner in developing novel therapies and understanding the molecular mechanisms of drug sensitivity/resistance.Herein,we summarized the application of CRISPR/Cas9 in drug screening,with the focus on CRISPR/Cas9 mediated gene knockout,gene knock-in,as well as transcriptional modification.Additionally,this review provides the concerns,cautions,and ethnic considerations that need to be taken when applying CRISPR in the drug discovery.展开更多
In order to investigate the multi drug resistance to Escherichia coli from captive population Amur tiger,E. coli strains were isolated from the fecal samples of tiger in Heilongjiang Amur Tiger Park in Harbin. The sen...In order to investigate the multi drug resistance to Escherichia coli from captive population Amur tiger,E. coli strains were isolated from the fecal samples of tiger in Heilongjiang Amur Tiger Park in Harbin. The sensitivity of E. coli isolates to 14 antibiotics was determined by scrip diffusion method. The results indicated that all the isolates varied in drug resistance to different antibiotics; the isolates gave high resistance to ampicillin,with a drug fast rate of 100%; over80% of the isolates were resistant to tetracycline and Paediatric Compound Sulfamethoxazole Tablets(SMZ- TMP),and over 70% of the isolates were sensitive to aztreonam,amoxicillin /potassium clavulanate. Most of the isolates had high sensitive to aztreonam and amoxicillin / clavulanate acid.展开更多
White feather broilers in some broiler farm in Chengde area developed arthritis and died acutely. In order to identify the pathogen inducing the disease and death of the white feather broilers, samples such as livers ...White feather broilers in some broiler farm in Chengde area developed arthritis and died acutely. In order to identify the pathogen inducing the disease and death of the white feather broilers, samples such as livers and joint pus were collected from dead broilers under sterile condition, and one pathogenic strain was isolated. The isolate was identified to be Staphylococcus aureus through isolated culture, morphologic observation, inspection of biochemical property and animal test. The drug sensitivity test showed that the isolate was sensitive to ceftazidime, enrofloxacin, ceftriaxone, lincomycin and amikacin, but resistant to other drugs to different degrees.展开更多
Objective:To analyze the clinical distribution and drug resistance of Acinetobacter baumannii(AB)and provide reference for the treatment of AB infection.Methods:AB isolated from clinical specimens of Huaihua First Peo...Objective:To analyze the clinical distribution and drug resistance of Acinetobacter baumannii(AB)and provide reference for the treatment of AB infection.Methods:AB isolated from clinical specimens of Huaihua First People’s Hospital from 2019 to 2021 were collected and identified by VITEK 2 Compact,an automated microbial identification and susceptibility testing system,in which drug sensitivity test was also performed.Excel was used for statistical analysis.Results:Among the 1,311 AB strains,81.16%(1,064 strains)were from sputum samples,and the departments with the highest detections rates of AB were neurosurgery(24.33%),intensive care(15.48%)and infectious disease(11.44%).The drug sensitivity test showed that the resistance rate of 1,311 AB strains to compound sulfamethoxazole and amikacin was 28.38%and 20.54%,respectively,and the resistance rate to 10 other kinds of common antibiotics was more than 40%.Conclusion:The 1,311 AB strains isolated were widely distributed in clinical settings and had strong resistance to commonly used antibiotics.Therefore,it is necessary to strengthen the monitoring of pathogens and drug resistance,formulate reasonable and effective infection control measures,and ensure that antibiotics are used in a reasonable manner.展开更多
Advanced LUAD shows limited response to treatment including immune therapy.With the development of sequencing omics,it is urgent to combine high-throughput multi-omics data to identify new immune checkpoint therapeuti...Advanced LUAD shows limited response to treatment including immune therapy.With the development of sequencing omics,it is urgent to combine high-throughput multi-omics data to identify new immune checkpoint therapeutic response markers.Using GSE72094(n=386)and GSE31210(n=226)gene expression profile data in the GEO database,we identified genes associated with lung adenocarcinoma(LUAD)death using tools such as“edgeR”and“maftools”and visualized the characteristics of these genes using the“circlize”R package.We constructed a prognostic model based on death-related genes and optimized the model using LASSO-Cox regression methods.By calculating the cell death index(CDI)of each individual,we divided LUAD patients into high and low CDI groups and examined the relationship between CDI and overall survival time by principal component analysis(PCA)and Kaplan-Meier analysis.We also used the“ConsensusClusterPlus”tool for unsupervised clustering of LUAD subtypes based on model genes.In addition,we collected data on the expression of immunomodulatory genes and model genes for each cohort and performed tumor microenvironment analyses.We also used the TIDE algorithm to predict immunotherapy responses in the CDI cohort.Finally,we studied the effect of PRKCD on the proliferation and migration of LUAD cells through cell culture experiments.The study utilized the TCGA-LUAD cohort(n=493)and identified 2,901 genes that are differentially expressed in patients with LUAD.Through KEGG and GO enrichment analysis,these genes were found to be involved in a wide range of biological pathways.The study also used univariate Cox regression models and LASSO regression analyses to identify 17 candidate genes that were best associated with mortality prognostic risk scores.By comparing the overall survival(OS)outcomes of patients with different CDI values,it was found that increased CDI levels were significantly associated with lower OS rates.In addition,the study used unsupervised cluster analysis to divide 115 LUAD patients into two distinct clusters with significant differences in OS timing.Finally,a prognostic indicator called CDI was established and its feasibility as an independent prognostic indicator was evaluated by Cox proportional risk regression analysis.The immunotherapy efficacy was more sensitive in the group with high expression of programmed cell death models.Relationship between programmed cell death(PCD)signature models and drug reactivity.After evaluating the median inhibitory concentration(IC50)of various drugs in LUAD samples,statistically significant differences in IC50 values were found in cohorts with high and low CDI status.Specifically,Gefitinib and Lapatinib had higher IC50 values in the high-CDI cohort,while Olaparib,Oxaliplatin,SB216763,and Axitinib had lower values.These results suggest that individuals with high CDI levels are sensitive to tyrosine kinase inhibitors and may be resistant to conventional chemotherapy.Therefore,this study constructed a gene model that can evaluate patient immunotherapy by using programmed cell death-related genes based on muti-omics.The CDI index composed of these programmed cell death-related genes reveals the heterogeneity of lung adenocarcinoma tumors and serves as a prognostic indicator for patients.展开更多
基金Supported by Inner Mongolia Natural Science Foundation and the 3rd Affiliated of Inner Medical University,No.2021MS08067.
文摘BACKGROUND Pancreatic cancer(PC)is one of the most aggressive malignancies characterized by rapid progression and poor prognosis.The involvement of cancer stem cells(CSCs)and Octamer transcription factor 4(OCT4)in PC pathobiology is being increasingly recognized.AIM To investigate the role of OCT4 in pancreatic CSCs and its effect on PC cell prolif-eration,migration,drug sensitivity,and stemness maintenance.METHODS We analyzed OCT4 and CD133 expression in PC tissues and cell lines.BxPC-3 cells were used to assess the effects of OCT4 modulation on cellular behavior.Proliferation,migration,and stemness of BxPC-3 cells were evaluated,and the PI3K/AKT/mTOR pathway was examined to gain mechanistic insights.RESULTS OCT4 and CD133 were significantly overexpressed in PC tissues.OCT4 mo-dulation altered BxPC-3 cell proliferation,invasion,and stemness,with OCT4 overexpression(OV-OCT4)enhancing these properties and OCT4 interference decreasing them.OV-OCT4 activated the PI3K/AKT/mTOR pathway,which correlated with an increase in PC stem cells(PCSC).CONCLUSION OCT4 plays a crucial role in PCSCs by influencing the aggressiveness and drug resistance of PC cells,thus presenting itself as a potential therapeutic target.
文摘Objective: To investigate the prevalence of myco-plasma infections and the sensitivity to antibiotics among patients with nongonococcal urethritis or cer-vicitis (NGU) in Chongqing. Methods: 387 NGU cases with mycoplasma-positive results upon culture were analysed retrospectively. RESULTS: The majority of patients with mycoplasma infections were in the 20-40 year old age group. No significant difference was found between males and females. Ureaplasma urealyticum is the main pathogen of these NGU cases and no clear relationship between its concentration and pathogenic ability was noted. Drug sensitivity was tested against nine antibiotics; the sensitivity rates to josamycim, minocycline and doxycycline were 94.06%, 88.89% and 86.82% respectively, while the resistance rates to lincomycin, ofloxacin, azithromycin and roxthromycin were 74.94%, 42.12%, 41.60% and 40.31% in turn. Conclusions: Josamycin, minocycline and doxycycline could be used as the first choice to treat NGU with mycoplasma infections in Chongqing. It is important to select antibiotics for NGU treatment with mycoplasma infections based on the results of drug sensitivity tests.
基金Project supported by the National Natural Science Foundation of China,No.39570806National Excel1ent Youth Scientific Foundation,No.3952020.
文摘AIM:To construct Hsp90 antisense RNA eukaryotic expression vector, transfect it into SGC7901 and SGC7901/VCR of MDR-type human gastric cancer cell lines, HCC7402 of human hepatic cancer and Ec109 of human esophageal cancer cell lines, and to study the cell cycle distribution of the gene transected cells and their response to chemotherapeutic drugs.METHODS:A 1.03kb cDNA sequence of Hsp90beta was obtained from the primary plasmid phHSP90 by EcoR I and BamH I nuclease digestion and was cloned to the EcoR I and BamH I site of the pcDNA by T4DNA ligase and an antisense orientation of Hsp90beta expression vector was constructed. The constructs were transfected with lipofectamine and positive clones were selected with G418. The expression of RNA was determined with dot blotting and RNase protection assay, and the expression of Hsp90 protein determined with western blot. Cell cycle distribution of the transfectants was analyzed with flow cytometry, and the drug sensitivity of the transfectants to Adriamycin (ADR), vincrinstine (VCR), mitomycin (MMC) and cyclophosphamide (CTX) with MTT and intracellular drug concentration of the transfectants was determined with flow cytometry.RESULTS:In EcoR I and BamH I restriction analysis, the size and the direction of the cloned sequence of Hsp90beta remained what had been designed and the gene constructs were named pcDNA-Hsp90.AH-SGC7901, AH-SGC7901/VCR, AH-HCC7402 and AH-Ec109 cell clones all expressed Hsp90 anti-sense RNA. The expression of Hsp90 was down-regulated in AH-SGC7901, AH-SGC7901/VCR, AH-HCC7402 and AH-Ec109 cell clones. Cell cycle distribution was changed differently. In AH-SGC7901/VCR and AH-Ec109 cells, G(1) phase cells were increased; S phase and G(2) phase cells were decreased as compared with their parental cell lines. In AH-SGC7901 cell, G(1)phase cells were decreased, G(2) phase cells increased and S phase cells were not changed, and in AH-HCC7402 cells G(1), S and G(2) phase cells remained unchanged as compared with their parental cell lines. The sensitivity of AH-SGC7901, AH-SGC7901/VCR, AH-HCC7402 and AH-Ec109 to chemotherapeutic drugs, the sensitivity of AH-SGC7901/VCR to ADR, VCR, MMC and CTX the sensitivity of AH-HCC7402 to ADR and VCR, and the sensitivity of Ec109 to ADR, VCR and CTX all increased as compared with their parental cell lines. The mean fluorescence intensity of ADR in AH-SGC7901, AH-SGC7901/VCR, AH-HCC7402 and AH-Ec109 was also significantly elevated (P 【 0.05).CONCLUSION: Down-regulation of Hsp90 could change cell cycle distribution and increase the drug sensitivity of tumor cells.
基金Supported by the Research Grants From the Thailand Research Fund and Khon Kaen University, Thailand Co-first-authors: Nisana Tepsiri and Liengchai Chaturat
文摘AIM: To study the effect of a number of chemotherapeutic drugs on five human intrahepatic cholangiocarcinoma (CCA) cell lines. The expressions of genes that have been proposed to influence the resistance of chemotherapeutic drugs including thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), glutathione-S-transferase PI (GSTP1), multidrug resistance protein (MDR1) and multidrug resistance-associated proteins (MRPs) were also determined. METHODS: Five human CCA cell lines (KKU-100, KKU-M055, KKU-M156, KKU-M214 and KKU-OCA17) were treated with various chemotherapeutic drugs and growth inhibition was determined by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. Semi-quantitative levels of gene expression were determined by a reverse transcriptase polymerase chain reaction (RT-PCR). Results of IC_(50) values and the ratios of gene expression were analyzed by linear regression to predict their relationship. RESULTS: Among five CCA cell lines, KKU-M055 was the most sensitive cell line towards all chemotherapeutic drugs investigated, particularly taxane derivatives with IC_(50) values of 0.02-3 nmol/L, whereas KKU-100 was apparently the least sensitive cell line. When compared to other chemotherapeutic agents, doxorubicin and pirarubicin showed the lowest IC_(50) values (＜5 μmol/L) in all five CCA cell lines. Results from RT-PCR showed that TS, MRP1, MRP3 and GSTP1 were highly expressed in these five CCA cell lines while DPD and MRP2 were only moderately expressed. It should be noted that MDR1 expression was detected only in KKU-OCA17 cell lines. A strong correlation was only found between the level of MRP3 expression and the IC_(50) values of etoposide, doxorubicin and pirarubicin (r=0.86-0.98, P＜0.05). CONCLUSION: Sensitivity to chemotherapeutic agents is not associated with the histological type of CCA. Choosing of the appropriate chemotherapeutic regimen for the treatment of CCA requires knowledge of drug sensitivity. MRP3 was correlated with resistance of CCA cell lines to etoposide, doxorubicin and pirarubicin, whereas other chemotherapeutic drugs showed no association. The role of this multidrug resistance-associated protein, MRP3, in chemotherapeutic resistance in CCA patients needs to be further investigated.
文摘Objective： Survivin is one of the apoptosis inhibitor genes and is rarely expressed in adult tissues. However, survivin expression has been detected in various human cancers and correlations have been recognized between the level of expression of this gene in tumors and prognosis. In this study, we investigated the effect of Survivin-siRNA on the drug sensitivity of osteosarcoma cell line MG-63. Methods： Two siRNAs （Survivin-siRNA1, Survivin-siRNA2） specifically targeting Survivin gene were chemically synthesized and transfected into MG-63 ceils. The Survivin mRNA level was detected by reverse transcription-polymerase chain reaction （RT-PCR）. The survivin protein expression and cell apoptosis rate were analyzed by flow cytometry （FCM）. The 50% inhibition concentration （IC50） of cisplatin （DDP） and adriamycin （ADM） on MG-63 cells was determined by MTT method. Results： Two short siRNA targeting survivin down-regulated the transcription of survivin gene dramatically and elevated apoptosis rate. They increased the drug sensitivity of MG-63 cells to ADM by five-fold and to DDP by nine-fold. Conclusion： Validated Survivin specific siRNA can effectively inhibit Survivin expression in survivin-overexpressing osteosarcoma MG-63 cell line and enhance the drug sensitivity of MG-63 cell line to ADM and DDP. Short survivin-siRNA mediated gene silencing may be a useful therapeutic strategy for osteosarcoma. These results suggest that survivin might be helpful for diagnosis of osteosarcoma and survivin siRNA combined with adriamycin or cisplatin may be a feasible strategy to enhance the effects of chemotherapy in patients with osteosarcoma.
基金Supported by Science and Technology Development Project of Shandong Province(2011YD210220)
文摘Ten pathogenic strains were isolated fi-om gingers infected by blast, and were identified by substrate utilization test and biochemical test. The identifica- tion results showed that these ten strains accorded with the basic characteristics of Pseudomonas solanacearum. Drug sensitivity test of ten strains was carried out, and prevention agents were screened to provide an experimental basis for the control of ginger blast.
基金Supported by Natural Science Foundation of Shandong Province(ZR2014CQ012)
文摘[ Objectives] The paper aimed to select drugs reasonably for treatment of rex rabbit colibacillosis, and to isolate the pathogenicity of Escherichia coll. [ Methods ] Pathogen isolation, drug sensitivity test and pathogen regression test were performed with rex rabbits killed by E. coli in clinic. [ Results] The isolate was E. coli 0-23, susceptible to amikacin and cefotaxime sodium; when the challenge dose was 1.0 mL/rabbit （about one billion E. coli）, the test animal would discharge mucous feces. [ Conclusions] The results provided model support for clinical medicine selection against rex rabbit colibacillosis.
基金Supported by Project of Hebei Education Department(ZD2017234)Project of Science and Technology Bureau of Shijiazhuang(171500953A)Project of Science and Technology Bureau of Qinhuangdao(201602A046)
文摘[Objectives] The study aimed to identify the pathogen that causes diarrhea in minks. [Methods] Liver tissues were aseptically collected from dead minks with diarrhea. By bacterial isolation and culture,morphological observation,biochemical test and pathogenicity test,the isolated strain was identified as pathogenic E. coli. [Results]The pathogen causing diarrhea in minks was confirmed as a pathogenic E. coli strain. Drug sensitivity test indicated that the isolated pathogenic E. coli strain was highly sensitive to ceftazidime,cefotaxime,enrofloxacin,florfenicol and cephradine,moderately sensitive to ampicillin,ciprofloxacin,amikacin,doxycycline,lincomycin and gentamycin,and resistant to amoxycillin,neomycin,spectinomycin,polymyxin and penicillin. [Conclusions] This study provided reference for the prevention and control of abortion in female minks in Qinhuangdao region.
文摘Purpose： Skin ulcer is a common type of disease affecting patients＇ health and quality of life, and bacterial infection increases the difficulty of its management. Methods： The present study collected the results of bacterial culture sampled from the surface of 110 cases of skin ulcers at our hospital from January 2011 to December 2012. We analyzed the constituent ratios of ulcer surface bacteria, the change in the main infectious bacteria and the results of drugsensitivity testing for common bacteria. In addition, the characteristics of bacterial infection of skin ulcers were summarized. Result： Of the 110 samples, 90 isolated bacteria were cultured. Sixty-one were Gram-negative bacteria, mainly comprising Pseudomonas aeruginosa, Klebsiella pneumoniae, Enterobacter cloacae and Escherichia coli. In addition, 23 isolates were Gram-positive bacteria, mainly comprising Staphylococcus aureus and Enterococcus faecalis. The probability of a negative bacterial culture in 2012 was significantly lower than that in 2011 （16.7% vs. 40.0%, p 〈 0.01）. Moreover, the probability of P. aeruginosa infection in 2012 was significantly higher than that in 2011 （31.7% vs. 14.0%, p 〈 0.01）. P. aeruginosa was resistant to seven commonly used antibiotics. Both K. pneumoniae and E. coli had higher resistance to ampicillin. E. cloacae were not sensitive to piperacillin/tazobactam. Acinetobacter baumannii was resistant to all the tested drugs. S. aureus, E. faecalis and Staphylococcus epidermidis had high resistance to clindamycin. There was other drug resistance to reflect the higher rate of skin bacterial resistance. Conclusion： Skin bacterial resistance rate is high. Gram-negative bacteria gradually account for the majority, and P. aeruginosa becomes the most important skin infection pathogen. These characteristics of bacterial infections of skin ulcers provide a significant reference for guiding the selection of antibiotics, better controlling infections of skin ulcers and accelerating the healing of skin ulcers.
基金The work was supported by Natural Science Foundation of Guangdong （No. 06021350）. Acknowledgements： We thank LIU Yang of the Duke University Medical Center in the United States for proofreading.
文摘Background All-trans retinoic acid （ATRA） can influence the tumor cell proliferation cycle, and some chemotherapeutic drugs are cycle specific. In this study, we hypothesize that ATRA can enhance chemotherapeutic drug sensitivity by affecting the cell cycle of tumor cells.Methods The cell cycle of LoVo cells was evaluated using flow cytometry （FCM）. Cell viability was analyzed using the MTT assay. The morphologic changes in the treated LoVo cells were measured with acridine orange （AO）/ethidium bromide （EB） staining. Expression of survivin in LoVo cells was analyzed by immunofluorescence assay.Results After LoVo cells were treated with ATRA, the G0/G1 ratio of the tumor cells increased and the cell ratio of S-and G2/M-phase decreased. Viability of the cells decreased significantly after combined treatment with ATRA and 5-fluorouracil （5-FU） or mitomycin c （MMC） and was evaluated by fluorescence microscopy. Expression level of survivin in the tumor cells decreased after ATRA combination treatment.Conclusions ATRA enhances drug sensitivity of the LoVo cell line to cell cycle-specific agents and inhibits the expression of survivin in LoVo cells. The combination of ATRA and 5-FU or MMC promoted cell apoptosis, and the mechanism involved in apoptosis may be related to inhibition of survivin gene expression.
文摘Since taking part as leading actors in driving the metastatic process,circulating tumor cells(CTCs)have displayed a wide range of potential applications in the cancer-related research field.Besides their well-proved prognostic value,the role of CTCs in both predictive and diagnostics terms might be extremely informative about cancer properties and therefore highly helpful in the clinical decision-making process.Unfortunately,CTCs are scarcely released in the blood circulation and their counts vary a lot among different types of cancer,therefore CTC detection and consequent characterization are still highly challenging.In this context,in vitro CTC cultures could potentially offer a great opportunity to expand the number of tumor cells isolated at different stages of the disease and thus simplify the analysis of their biological and molecular features,allowing a deeper comprehension of the nature of neoplastic diseases.The aim of this review is to highlight the main attempts to establish in vitro CTC cultures from patients harboring different tumor types in order to highlight how powerful this practice could be,especially in optimizing the therapeutic strategies available in clinical practice and potentially preventing or contrasting the development of treatment resistance.
基金The study was supported by the National Natural Science Foundation of China(Grant No.90209048)and the Knowledge Innovation Program of the Chinese Academy of Sciences(Nos.KSCX2-SW-329 and KGCX2-SW-213).
文摘In order to provide a sensitive cell line model for investigating the mechanisms underlying the lymphatic metastasis of tumors and the effect of medicine against cells,a new murine ascites hepatocarcinoma cell line with high lymphatic metastatic potential(Hca-P/L_(6))was established and the effect of curcumin on biological behavior of Hca-P/L_(6) was observed.Murine ascites hepatocarcinoma cell strain with low lymphatic metastatic potential(Hca-P)was subcutaneously inoculated into the medioventral line of a mouse 615 and thefirst generation of metastatic tumor cells of inguinal lymph node(Hca-P/L_(1))was obtained.Then,Hca-P/L_(1) was screened by the route of mouse foot pad subcutaneously!lymph node!scale-up culture in vitro!mouse foot pad subcuta-neously forfive times consecutively.The sensitivity of two murine ascites hepatocarcinoma cell lines(Hca-P and Hca-P/L_(6))and two anchorage-dependent human hepato-carcinoma cell lines(SMC7721 and HepG_(2))to curcumin were studied by use of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay after these cells had been pretreated by curcumin at the concentration of 15–240μmol/L for 48 h.After pretreatment by curcumin at the maximum non-cytotoxic dose of 15μmol/L in vitro,the effect of curcumin against cell proliferation of Hca-P and Hca-P/L6 was observed by inverted micro-scope,cell growth curve and cell population doubling time;the effects of curcumin on cell cycles of Hca-P/L6 and Hca-P were studied byflow cytometry(FCM).The results showed Hca-P/L_(6) spreading to the lymph nodes at multiple sites in mice was screened from Hca-P.The lymph node metastatic rate was 100%.Curcumin had significant growth inhibiting effect on both murine ascites and human hepatocarcinoma cell lines in a dose-dependent manner(P<0.05).At concentrations of 30–120μmol/L,curcu-min had more inhibition on murine ascites hepatocarci-noma cell lines than on human anchorage-dependent hepatocarcinoma cell lines.At concentrations of 60–240μmol/L,curcumin had more inhibition on Hca-P/L_(6) with the 50%inhibitory concentration(IC50)of 51.48μmol/L than on Hca-P with IC50 of 90.87μmol/L.After pretreatment by curcumin at the maximum non-cytotoxic dose of 15 mol/L for 7 days,the proliferations of Hca-P/L_(6) and Hca-P were inhibited(P<0.05)in a time-dependent manner(P<0.01)and the population doubling time of Hca-P/L6 and Hca-P was prolonged(P<0.01),and curcumin had more inhibition on Hca-P/L6 than on Hca-P(P<0.05).After pretreatment by 15μmol/L curcumin for 48 h,the morphous of Hca-P/L_(6) was influenced more seriously than that of Hca-P and the cell cycle was redistributed with Hca-P/L6 being blocked in the S phase and Hca-P in the S and G_(2)/M phases.Hca-P/L_(6) was validated to be more sensitive to curcumin than Hca-P.Hca-P/L_(6) is a novel sensitive cell line model for investigating the mechanisms underlying tumor lymphatic metastasis and the effect of the medicine against cells.
文摘OBJECTIVE To explore whether MDM2 transfection can alter the MDM2-p53 autoregulatory feedback loop so as to change the sensitivity of ovarian cancer cell lines to cisplatin. METHODS The ovarian cancer cell line A2780 expressing wild-type P53 and the ovarian cancer cell line SKOV-3 with the p53 null type were stably transfected with pCMV-MDM2 or pCMV as a control. The blocked expression of P53 was determined by Western blots. Cytotoxicity was assessed using the MTT assay and the trypan blue exclusion assay. Flow cytometry was used to detect changes in the cell cycle and removal of platinum -DNA adducts was measured by atomic absorption spec-troscopy. RESULTS (1) Parental A2780 and A2780-V cells (IC50= 15.14±1.39 μmol) have similar cisplatin sensitivities, whereas sensitivity to cisplatin in A2780-M cells (IC50=7.98±1.32 μmol) was 2 to 3 fold greater (P=0.001). The trypan blue exclusion assay demonstrated that cisplatin killed a higher percentage of A2780-M cells compared to A2780-V cells. There was no significant change following MDM2 transfection in SKOV-3 cells. (2) After cisplatin treatment, A2780-M cells showed a pronounced S-phase arrest, however, A2780 cells with the intact wild-type P53, arrested primarily at the G2/M transition. (3) Platinum uptake was similar for all of the A2780 cell lines after ciaplatin treatment, but the removal of plat-inum-DNA adducts was reduced in the A2780-M cells compared with A2780-V cells. CONCLUSION MDM2 increases cisplatin cytotoxicity in ovarian cancer cells by blocking the expression of p53 through the MDM2-p53 autoregulatory feedback loop.
文摘[Objective] This study aimed to isolate and identify the drug-resistant Es- cherichia coli strains from chickens. [Method] E. coli strains were isolated from the fecal samples collected from five chicken farms around Shangqiu City, and verified by biochemical and pathogenic assay. [Result] Among the 35 isolated E. coli stains, 11 E. coil stains were sensitive to florfenicol, amikacin, neomycin and gentamicin; 12 E. coli stains were moderately sensitive to ciprofloxacin, doxycycline and norfloxacin; 15 E. coil stains were resistant against erythromycin, penicillin and streptomycin. [Conclusion] Strengthening biosecurity measures, rationally using vaccine and choosing effective antibiotics are the most cost-efficient methods to control E. coli.
文摘Objective： The aim of this study was to study the cisplatin sensitizing effect and mechanism of anti-HPV16 E6- ribozyme on cervical carcinoma cell line. Methods： The anti-HPV16E6-ribozyme and empty eucaryotic expressing plasmids were transfected into CaSKi cell, which named as CaSKi-R, CaSKi-P respectively. E6 mRNA, the sensitivity to cisplatin, apoptosis rates, expression of p53, Bcl-2, Bax and C-myc proteins and mRNA were examined by Northem blot, MTT colorimetric assay, PI/Annexin V stained methods, flow cytometry anslysis and RT-PCR, respectively. Results： E6 mRNA was less in CaSKi-R than in CaSKi. The sensitivity of CaSKi-R cells to cisplatin was 2.28 and 2.21 times than that of CaSKi and CaSKi-P cells. The apoptotic rates in CaSKi, CaSKi-P and CaSKi-R cells was （18.9 ± 3.5）%, （19.7 ± 4.8）% and （40.4 ± 4.5）%. The apoptotic rates was increased in CaSKi-R than that of CaSKi cells treated with cisplatin （P = 0.003）. Comapred with CaSKi cell, the expression of p53 （P = 0.000）, Bax protein （P = 0.002） was significantly higher and the expression of Bcl-2 protein （P = 0.005）, C-myc protein （P = 0.005） was significantly lower in CaSKi-R than that of CaSKi cell treated with cisplatin. Comapred with CaSKi cell, the expression of p53, Bax mRNA in CaSKi-R cell treated with cisplatin increased, while Bcl-2, C-myc mRNA decreased. Conclusion： CaSKi-R cells transfected by anti-HPVE6-ribozyme increased the sensitivity to cisplatin. The increase of sensitivity to cisplatin in CaSKi-R cells may be associated with increasing expression of p53, Bax protein, and decreasing expression of C-myc, Bcl-2 proteins.
基金This work was supported by the Start-Up funding from Anhui Medical University(KZ 0801033201),and the Doctoral Research Funding from the Cancer Society of Finland(KZ).
文摘Emerging cohorts and basic studies have associated certain genetic modifications in cancer patients,such as gene mutation,amplification,or deletion,with the overall survival prognosis,underscoring patients’genetic background may directly regulate drug sensitivity/resistance during chemotherapies.Understanding the molecular mechanism underpinning drug sensitivity/resistance and further uncovering the effective drugs have been the major ambition in the cancer drug discovery.The emergence and popularity of CRISPR/Cas9 technology have reformed the entire life science research,providing a precise and simplified genome editing tool with unlimited editing possibilities.Furthermore,it presents a powerful tool in cancer drug discovery,which hopefully facilitates us with a rapid and reliable manner in developing novel therapies and understanding the molecular mechanisms of drug sensitivity/resistance.Herein,we summarized the application of CRISPR/Cas9 in drug screening,with the focus on CRISPR/Cas9 mediated gene knockout,gene knock-in,as well as transcriptional modification.Additionally,this review provides the concerns,cautions,and ethnic considerations that need to be taken when applying CRISPR in the drug discovery.
基金Supported by Fundamental Research Funds for the Central Universities(DL12BA04)
文摘In order to investigate the multi drug resistance to Escherichia coli from captive population Amur tiger,E. coli strains were isolated from the fecal samples of tiger in Heilongjiang Amur Tiger Park in Harbin. The sensitivity of E. coli isolates to 14 antibiotics was determined by scrip diffusion method. The results indicated that all the isolates varied in drug resistance to different antibiotics; the isolates gave high resistance to ampicillin,with a drug fast rate of 100%; over80% of the isolates were resistant to tetracycline and Paediatric Compound Sulfamethoxazole Tablets(SMZ- TMP),and over 70% of the isolates were sensitive to aztreonam,amoxicillin /potassium clavulanate. Most of the isolates had high sensitive to aztreonam and amoxicillin / clavulanate acid.
基金Supported by Hebei Science and Technology Deparment Project(17226607D)
文摘White feather broilers in some broiler farm in Chengde area developed arthritis and died acutely. In order to identify the pathogen inducing the disease and death of the white feather broilers, samples such as livers and joint pus were collected from dead broilers under sterile condition, and one pathogenic strain was isolated. The isolate was identified to be Staphylococcus aureus through isolated culture, morphologic observation, inspection of biochemical property and animal test. The drug sensitivity test showed that the isolate was sensitive to ceftazidime, enrofloxacin, ceftriaxone, lincomycin and amikacin, but resistant to other drugs to different degrees.
基金the Scientific Research Project of Hunan Provincial Department of Education(19C1328)the Research-Based Learning and Innovative Experimental Program for College Students in Hunan Province(S202012214040).
文摘Objective:To analyze the clinical distribution and drug resistance of Acinetobacter baumannii(AB)and provide reference for the treatment of AB infection.Methods:AB isolated from clinical specimens of Huaihua First People’s Hospital from 2019 to 2021 were collected and identified by VITEK 2 Compact,an automated microbial identification and susceptibility testing system,in which drug sensitivity test was also performed.Excel was used for statistical analysis.Results:Among the 1,311 AB strains,81.16%(1,064 strains)were from sputum samples,and the departments with the highest detections rates of AB were neurosurgery(24.33%),intensive care(15.48%)and infectious disease(11.44%).The drug sensitivity test showed that the resistance rate of 1,311 AB strains to compound sulfamethoxazole and amikacin was 28.38%and 20.54%,respectively,and the resistance rate to 10 other kinds of common antibiotics was more than 40%.Conclusion:The 1,311 AB strains isolated were widely distributed in clinical settings and had strong resistance to commonly used antibiotics.Therefore,it is necessary to strengthen the monitoring of pathogens and drug resistance,formulate reasonable and effective infection control measures,and ensure that antibiotics are used in a reasonable manner.
基金National Natural Science Foundation of China(Grant No.81273297)Shenyang Science and Technology Plan.Public Health R&D Special Project(21-173-9-67).
文摘Advanced LUAD shows limited response to treatment including immune therapy.With the development of sequencing omics,it is urgent to combine high-throughput multi-omics data to identify new immune checkpoint therapeutic response markers.Using GSE72094(n=386)and GSE31210(n=226)gene expression profile data in the GEO database,we identified genes associated with lung adenocarcinoma(LUAD)death using tools such as“edgeR”and“maftools”and visualized the characteristics of these genes using the“circlize”R package.We constructed a prognostic model based on death-related genes and optimized the model using LASSO-Cox regression methods.By calculating the cell death index(CDI)of each individual,we divided LUAD patients into high and low CDI groups and examined the relationship between CDI and overall survival time by principal component analysis(PCA)and Kaplan-Meier analysis.We also used the“ConsensusClusterPlus”tool for unsupervised clustering of LUAD subtypes based on model genes.In addition,we collected data on the expression of immunomodulatory genes and model genes for each cohort and performed tumor microenvironment analyses.We also used the TIDE algorithm to predict immunotherapy responses in the CDI cohort.Finally,we studied the effect of PRKCD on the proliferation and migration of LUAD cells through cell culture experiments.The study utilized the TCGA-LUAD cohort(n=493)and identified 2,901 genes that are differentially expressed in patients with LUAD.Through KEGG and GO enrichment analysis,these genes were found to be involved in a wide range of biological pathways.The study also used univariate Cox regression models and LASSO regression analyses to identify 17 candidate genes that were best associated with mortality prognostic risk scores.By comparing the overall survival(OS)outcomes of patients with different CDI values,it was found that increased CDI levels were significantly associated with lower OS rates.In addition,the study used unsupervised cluster analysis to divide 115 LUAD patients into two distinct clusters with significant differences in OS timing.Finally,a prognostic indicator called CDI was established and its feasibility as an independent prognostic indicator was evaluated by Cox proportional risk regression analysis.The immunotherapy efficacy was more sensitive in the group with high expression of programmed cell death models.Relationship between programmed cell death(PCD)signature models and drug reactivity.After evaluating the median inhibitory concentration(IC50)of various drugs in LUAD samples,statistically significant differences in IC50 values were found in cohorts with high and low CDI status.Specifically,Gefitinib and Lapatinib had higher IC50 values in the high-CDI cohort,while Olaparib,Oxaliplatin,SB216763,and Axitinib had lower values.These results suggest that individuals with high CDI levels are sensitive to tyrosine kinase inhibitors and may be resistant to conventional chemotherapy.Therefore,this study constructed a gene model that can evaluate patient immunotherapy by using programmed cell death-related genes based on muti-omics.The CDI index composed of these programmed cell death-related genes reveals the heterogeneity of lung adenocarcinoma tumors and serves as a prognostic indicator for patients.
