Objective To observe the effect of resveratrol on multidrug resistance (MDR) in human retinoblastoma cells treated. Methods RB cells in logarithmic growth phase were divided into experimental group and control group. RB cells in experimental group were cultured with different concentrations of resveratrol (6.25, 12.50, 25.00, 50.00, 100.00 mu;mol/L) for 24 and 48 hours. The proliferation (absorbance value) was assayed using methyl thiazolyl tetrazolium (MTT). RB cells were cultured with 50.00 mu;mol/L resveratrol for 48 hours. The expressions of MDR-1, cyclooxygenase-2 (COX-2)、multidrug resistance-associated protein-1 (MRP-1), glutathione-S-transferases-pi; (GST-pi;) were determined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. The RB cells of the control group were cultured with 0.5% dimethyl sulfoxide. Results Compared with the control group, the absorbance value decreased in experimental groups (6.25, 12.50, 25.00, 50.00 mu;mol/L) in a dose dependent manner (F=4.782，P＜0.05). The difference of absorbance value between 50.00 and 100.00 mu;mol/L experimental groups was not significant (F=6.351,P＞0.05). Compared with the control group, the mRNA (t=9.170, 5.758, 4.152, 4.638) and protein (t=3.848, 5.955, 4.541, 3.514) expression levels of MDR-1, MRP1, COX-2, and GST-pi; decreased in the experimental group (P＜0.05). Conclusion Resveratrol can down-regulate the expression of MDR in RB cells.
【Abstract】ObjectiveTo establish adriamycin (ADM) resistant pancreatic cancer cell line SW1990/ADM and to investigate its drug resistance mechanism.MethodsADM-resistant pancreatic cancer cell line SW1990/ADM was obtained by culture of pancreatic cancer cell line SW1990 in vitro with intermittently increasing the concentration of ADM in the culture medium for ten months. After two months of drug free culture, its biological characteristics, drug sensitivity as well as the expression and function of multidrug resistant gene 1 (mdr1) were detected, respectively. ResultsCompared with the parental cell line, SW1990/ADM showed great changes in biological characteristics and developed a cross resistance to various chemotherapy drugs. The drug resistance indexes of cell line SW1990/ADM to ADM, mitomycin, fluorouracil and gemcitabine were 49.60, 7.25, 3.80 and 1.25, respectively. The level of mdr1 mRNA expression in cell line SW1990/ADM was much higher than that of the parental cell line（P＜0.01). ConclusionWe have established adriamycin resistant pancreatic cancer cell line SW1990/ADM with multidrug resistance phenotype, its multidrug resistance is positively relevant to the expression of mdr1.
ObjectiveTo investigate the distribution and drug resistance of the pathogens isolated from hospitalized pediatric patients with respiratory tract infections, and to provide guidance for empiric therapy. MethodsRespiratory tract specimens from hospitalized pediatric patients with respiratory tract infections from 2011 to 2015 were collected, and the strains were identified and the drug susceptibility was tested. ResultsA total of 1995 strains of pathogens, 1281 (64.21%) from boys and 714 (35.79%) from girls, were isolated from 6236 specimens and the detection rate was 31.99%. The mean age of the hospitalized pediatric patients was (1.22±2.05) years (ranged from 1 day to 14 years). 1393 (69.82%) pediatric patients were younger than 1 year. Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Candida albicans and Acinetobacter baumannii ranked the top five species, accounting for 29.82%, 15.09%, 13.18%, 12.73% and 5.91%, respectively. 1995 strains included gram-negative bacteria (50.93%), gram-positive bacteria (35.29%), and fungi (13.78%). The resistance rate of Staphylococcus aureus to oxacillin was 31.76%, but it was 100% sensitive to vancomycin and linezolid. The resistant rate of gram-negative bacteria to imipenem was ranged from 1.52% to 5.93%. The resistant rate of gram-negative bacteria to ceftazidime, cefepime, piperacillin tazobactam and tobramycin was less than 30.00%. ConclusionsThe infants whose age are younger than 1 year comprise the majority of the hospitalized pediatric patients with respiratory tract infections. The proportion of male is more than that of female. Staphylococcus aureus and enterobacteriaceae were the main isolated pathogens. There is difference in drug resistance between different pathogens, so antibiotics should be chosen according to the results of drug sensitivity testing.
Objective To investigate the drug resistance and homogeneous analysis of Acinetobacter baumanii in emergency intensive care unit ( EICU) . Methods Four multidrug-resistant Acinetobacter baumannii ( MDR-Ab) strains isolated fromnosocomial inpatients fromJuly 25 to September 7 in 2009 were collected and tested for drug sensitivity and MIC determination as well. The A. baumannii isolates were typed with pulsed-field gel electrophoresis ( PFGE) to determine whether they derived fromthe same clone.Results Four isolates from nosocomial inpatients were resistant to multiple antibiotics including carbapenem. The PFGE types identified from four isolates were A and B. The A. baumannii isolates did not derived from the same clone. Conclusion The prevalence of nosocomial infection is not due to transmission of the same strains among different individuals in EICU.
ObjectiveTo summarize progression of growth factor receptor (GFR) signaling pathway in endocrineresistant breast cancer. Method Literatures about mechanisms of GFR signaling pathway in the development of endocrineresistant breast cancer were reviewed. ResultsThe crosstalk between GFR and estrogen receptor (ER) signaling pathway had been reported to be involved in the development of endocrine-resistant breast cancer. Interrupting this signaling pathway could overcome endocrine therapy resistance. Many clinical trails had shown that the utilizing endocrine therapy combined with GFR inhibitors could obviously increase the survival rate of patients with breast cancer. ConclusionSeveral agents targeting GFR signaling pathways show a great potential for treatment of patients with breast cancer.
ObjectiveTo study the clinical distribution and the change of drug resistance of Acinetobacter baumannii from different inpatient specimens sources during 2008 to 2012, and to provide guidance for rational use of antibiotics. MethodsThe identification of Acinetobacter baumannii was conducted by VITEK-2 based on clinical and laboratory standards institute (CLSI) guideline between January 2008 and December 2012. The susceptibility of antibiotics was determined by K-B test, and data analysis was conducted by Excel and SAS. ResultsA total of 3 139 stains of Acinetobacter baumannii were isolated from 2013 patients during this period. The Acinetobacter baumannii was mainly obtained from the Burn ward, Intensive Care Unit ward and Thoracic ward. Sputum was the most specimens of Acinetobacter baumannii, accounting for 48.4%. The drug resistance rates of Acinetobacter baumannii to most of the antimicrobial agents were more than 55%. Compound antibacterial is more effective than the single drug ingredient. Compared with other antimicrobial agents, β-lactams/β-lactamase inhibitor compound and carbapenems antimicrobial agents were more sensitive. ConclusionThe drug resistance of Acinetobacter baumannii is serious and has differences among hospitals. Clinicians should monitor the drug resistance of Acinetobacter baumannii timely and choose proper antibiotics according to the results of drug sensitivity.
The issue of bacterial drug resistance has remained unresolved, and in recent years, biomimetic nanostructured surfaces inspired by nature have garnered significant attention due to their bactericidal properties demonstrated through mechanical mechanisms. This article reviewed the main research progress in the field of nanostructured mechanical bactericidal surfaces, including various preparation methods for nanostructured surfaces with mechanical bactericidal properties, as well as the basic mechanisms and related physical models of the interaction between bacteria and nanostructured surfaces. In addition, the application of nanostructured surfaces in biomedicine was introduced. Finally, the article proposed the major challenges faced by mechanical bactericidal research and the future development direction.
Objective To observe the regional expression of hypoxia inducible factor-1alpha; (HIF-1alpha;) in retinoblastoma and its relationships with vascular endothelial growth factor (VEGF), Bax and Ki-67. Methods Immunohistochemical study for HIF-1alpha;, VEGF, Bax and Ki-67 was performed in 39 paraffinaceous examples of retinoblastoma. Each pathological section was divided into five regions: the surface region, the central part, the bottom part, the choroidal region and seeding tumors. The expressions, correlations and distributional differences of these factors were all invested both integrally and regionally. Results In the 39 cases of retinoblastoma, 10 cases (25.6%) were negative for HIF-1alpha;; 29 cases (74.4%) were positive for HIF-1alpha;, including 17 cases (43.6%) (+), 12 cases (30.8%) (++). Regionally, HIF-1alpha; was positive in 71.1%, 36.8%, 84.2%, 54.5% and 82.1% of the cases in the surface region, the central part, the bottom part, the choroidal region and seeding tumors, respectively, which was statistically reliable (chi;2=24.55，P＜0.001). The positive rate of VEGF, Bax and Ki-67 was 53.8%, 66.7% and 59.0%, respectively. In different regions, the positive rates of VEGF and Bax were different (chi;2=26.77, 22.79; P＜0.001), but there was no regional distinctions in the expression of Ki-67 (chi;2=0.47, P=0.976). Both the expression of VEGF and Bax had a positive correlation with that of HIF-1alpha;(rs=0.48, 0.39; P=0.002, 0.021), but there was no relationship between the expressions of Ki-67 and that of HIF-1alpha; (rs=0.09, P=0.606). Regionally, the expressions of VEGF, Bax and HIF-1alpha; shared similar distributional features: positive rates were higher in the surface region, bottom part and seeding tumors, and were lower in the central part and choroidal region, which was different from the expression of Ki-67. Conclusion The anoxic zones are more likely to be located in the marginal parts in retinoblastoma, and the expressions of VEGF and Bax had a positive correlation with that of HIF-1alpha; in different regions in retinoblastoma.
Objective To analyze the clinical and etiological characteristics and bacterial susceptibility in patients with ventilator-associated pneumonia (VAP) in Guangzhou area.Methods A retrospective study was conducted on VAP patients in four hospital of Guangzhou from Jan 2004 to Oct 2005.Totally 157 patients were enrolled in this study，whose flora was identified and tested by Kirby Bauer disk diffusion susceptibility test.The univariate analysis method was used to analyze the prognostic parameters.Results The average onset time of VAP was 7.7 days after mechanical ventilation with a mortality rate of 38.2%.The proportion of Gram-negative bacilli，Gram-positive cocci and eumycete was 68.0%，23.4% and 8.7% respectively in 184 isolated strains.The most common pathogens were Pseudomonas aeruginosa (18.5%)，Stenotrophomonas maltophilia (14.1％)，Burkholderia cepacia (10.9%)，Staphylococcus aureus (10.3%) and Acinetobacter baumannii (8.7%).Pseudomonas aeruginosa，Stenotrophomonas maltophilia，and Acinetobacter baumannii were resistant to most common antibacterials such as cephalosporin and imipenem.18 strains oxacillin resistant Staphylococcus aureus，7 strains oxacillin resistant Staphylococcus simulans and one vancomycin resistant Staphylococcus aureus were isolated.Expect for vancomycin，teicoplanin and fusidic acid，the resistance of Gram-positive cocci were above 50% to other 9 antibacterials.Conclusions The antibiotic resistance situation of VAP in Guangzhou is very serious with high mortality.It is important to reinforce the prevention and guidance on the proper treatment of VAP.
Objective To study the efficacy and safety of combined anti-tuberculosis regimen containing bedaquiline in the treatment of multidrug-resistant tuberculosis (MDR-TB). Methods A total of 69 MDR-TB patients treated by joint regimen combined bedaquiline with other anti-tuberculosis drugs between March 2018 and August 2019 in Public Health Clinical Center of Chengdu were taken as the trial group, and 60 MDR-TB patients received treatment without bedaquiline between June 2016 and December 2017 in the same hospital were taken as the control group. The efficacy and safety of the two groups were compared. Results The 69 patients in the trial group included 44 males and 25 females, aged from 21 to 63 years, with an average of (34.6±11.0) years; 58 patients (84.1%) completed the 24-week treatment with bedaquiline, while 11 patients did not complete the treatment, including 3 deaths (4.3%), 1 loss of follow-up (1.4%), 1 withdrawal from the study (1.4%), and 6 discontinuation due to adverse events (8.7%). Among the 54 patients with positive results of tuberculosis on baseline sputum culture, 49 transformed to negative results within 24 weeks of treatment (the negative conversion rate was 90.7%), and the median negative conversion time was 13.0 weeks. The 60 patients in the control group included 45 males and 15 females, aged from 16 to 66 years, with an average of (35.5±13.2) years. Among the 53 patients with positive results of tuberculosis on baseline sputum culture, 30 transformed to negative results within 24 weeks of treatment (the negative conversion rate was 56.6%), and the median negative conversion time was 12.0 weeks. The negative conversion rate of sputum bacteria in the trial group was significantly higher than that in the control group (χ2=16.133, P<0.001). The most common adverse reactions in the trial group were liver function abnormalities (42 cases, 60.9%), prolonged QTc interval (37 cases, 53.6%), electrolyte disturbances (20 cases, 29.0%), and blood system damage (20 cases, 29.0%). In the 37 patients who experienced prolonged QTc interval, there were 8 patients with QTc intervals≥500 ms and 29 patients with QTc intervals ≥450 ms and <500 ms, with a median occurrence time of 16.0 weeks, among whom 25 patients experienced prolonged QTc interval in 4-48 weeks after the withdrawal of bedaquiline. Conclusion The negative conversion rate of tuberculosis sputum culture of patients with MDR-TB treated by bedaquiline combined with other anti- tuberculosis drugs is high, but electrocardiogram should be closely monitored during and after the treatment in order to guard against the potential cardiac toxic effects of bedaquiline.