We have studied the radiosenstivity of retinoblastoma cell [inc: HXO Rb~4,and found that the ceil growth reduced markedly after being treated by 3GyT-ray. From both clone for mation method and MTT assay,we identify that HXO-Rb44 cell is radiosensitive to T-ray.Oxygen can increase the radiosensitivity of HXO-Rb44 cell, but decrease the repair of sublethal damage.Oxygen enchaneement ratio(OER)is 2.77~3.01.
（Chin J Ocul Fundus Dis,1994,10:217-219）
Objective
To probe the distribution and drug resistance of pathogens causing surgical site infection in patients after gynecologic operation, and provide reference for prevention and treatment.
Methods
Seventy patients with incision infection after gynecologic operation in West China Second University Hospital of Sichuan University from January 2010 to May 2015 were selected. Species of the pathogens from the submitted specimens and the results of the drug susceptibility testing were analyzed.
Results
Seventy-two strains of pathogens were isolated, including 36 strains (50.0%) of Gram-negative (G–) bacteria and 36 strains (50.0%) of Gram-positive (G+) bacteria. The main G– bacteria were Escherichia coli (36.1%) and Enterobacter cloacae (5.6%); the main G+ bacteria were Staphylococcus aureus (18.1%), Staphylococcus epidermidis (12.5%), and Enterococcus faecalis (8.3%). Escherichia coli showed low sensitivities to ampicillin, ceftriaxone, and gentamicin, with resistance rates of 76.9%, 61.5%, and 61.5%, respectively. Staphylococcus aureus showed low sensitivities to penicillin G, clindamycin, and erythromycin, with resistance rates of 92.3%, 69.2%, and 61.5%, respectively. Staphylococcus epidermidis showed low sensitivities to erythromycin, penicillin G, and ciprofloxacin, with resistance rates of 88.9%, 77.8%, and 77.8%, respectively. No carbapenem-resistant G– bacteria or vancomycin-resistant G+ bacteria were detected.
Conclusion
Postoperative surgical site infection is the most common nosocomial infection. The main bacteria related to postoperative incision infection in the gynecology department of the hospital are Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, and Enterococcus faecalis, which become resistant to common antibiotics currently. Therefore more attention should be paid to bacterial isolation and drug susceptibility test results for rational use of antimicrobial drugs and effectiveness of the treatment to nosocomial infection.
ObjectiveTo understand the drug resistance of Mycobacterium tuberculosis complex in West China Hospital, Sichuan University, analyze its drug resistance characteristics, and provide reference for the monitoring of drug-resistant tuberculosis.MethodsFrom January 2016 to March 2018, Mycobacterium tuberculosis drug susceptibility testing kit was used to detect the drug susceptibility of Mycobacterium tuberculosis culture-positive strains in Department of Laboratory Medicine, West China Hospital, Sichuan University. The tested drugs included four of the first-line anti-tuberculosis drugs: rifampicin, isoniazid, ethambutol, and streptomycin, and ten of the second-line anti-tuberculosis drugs: capreomycin, ofloxacin, ethionamide, p-aminosalicylic acid, levofloxacin, moxifloxacin, rifabutin, amikacin, kanamycin, and chlorine phenazine.ResultsA total of 130 patients (130 strains) were enrolled, including 82 newly diagnosed patients (82 strains) and 48 re-treated patients (42 strains). The drug resistance rate of the 130 patients was 37.69%. The drug resistance rate of the newly diagnosed patients (28.05%) was significantly lower than that of the re-treated patients (54.17%), and there was a statistical difference (χ2=8.794, P=0.003). The multi-drug resistance rate of the newly diagnosed patients (6.10%) was significantly lower than that of the re-treated patients (25.00%), and the difference was statistically significant (χ2=9.517, P=0.002). The resistance rate of isoniazid, rifampicin, and streptomycin in newly diagnosed patients (23.17%, 8.54%, and 7.32%, respectively) were significantly lower than those in the re-treated patients (45.83%, 41.67%, and 29.17%, respectively), and the differences were statistically significant (P<0.05). The resistance rate of ofloxacin, moxifloxacin, rifabutin and ethionamide in the newly diagnosed patients (9.76%, 8.54%, 7.31%, and 4.88%, respectively) were significantly lower than those in the re-treated patients (39.58%, 27.08%, 25.00%, and 22.92%, respectively), and the differences were statistically significant (P<0.05).ConclusionIt is necessary to strengthen the standardized treatment of patients with newly diagnosed tuberculosis, increase the treatment and management of re-treated tuberculosis patients, and prevent the generation and spread of drug-resistant patients, especially multidrug-resistant patients.
ObjectiveTo detect the expression of microRNA-497(miR-497) in gastric cancer and its biological significance, and to find out its regulatory links with other genes and investigate the effect of miR-497 overexpression interference on chemotherapy sensitivity of gastric cancer cell line.
MethodsNinety-four gastric cancer tissues and adjacent to cancer tissues from 2010 to 2013 in this hospital were collected. The expression of miR-497 in the gastric cancer tissue or adjacent to cancer tissue was detected by real-time PCR. SGC-7901 cell line was transfected by miR-497-negative control and miR-497-mimics, respectively. The BCL2L2 expression was measured by Western blot after upregulation of miR-497. The chemotherapy sensitivity of cell line was tested by MTT assay.
Results①The expression of miR-497 was significantly downregulated in the gastric cancer tissues as compared with the adjacent to cancer tissues (P < 0.01). 2 BCL2L2 was predicted to target gene of miR-497. after miR-497 overexpression in cells, the expression of BCL2L2 protein was decreased in the miR-497-mimics cells as compared with negative control cells. The IC50 in the miR-497-mimics cells was significantly lower than that in the negative control cells(P=0.004 6).
ConclusionsmiR-497 expression is frequently downregulated in gastric cancer tissue. Overexpression of miR-497 could inhibit the expression of target gene BCL2L2, and improve chemotherapy sensitivity of gastric cancer cell line, which implies that miR-497 may play an important role in carcinogenesis and therapy of gastric cancer.
Objective To investigate the effects of matrine on proliferation, apoptosis and radiotherapy sensitivity of uveal melanoma cells. MethodsAn animal experiment study. In vitro experiment: MuM2B cells of human choroidal melanoma were randomly divided into control group and matrine 0.25, 0.50, 1.00, 2.00 g/L groups. The cell morphology was observed by transmission electron microscope. Cell proliferation was detected by thiazole blue colorimetry. The mRNA and relative expression levels of CyclinD D (CyclinD), B lymphoblastoma-2 (Bcl-2) and Bcl2-associated X protein (Bax) were detected by real-time polymerase chain reaction and Western blot. In vivo experiment: BALB/C mice were injected with MuM2B cell suspension subcutaneously on the back of forelimb to prepare transplanted tumor model. After successful modeling, they were randomly divided into blank group and matrine treatment group with different concentrations. Mice in blank group were injected with phosphate buffer subcutaneously. Mice in different matrine treatment groups were injected with 15, 25, 50, 100 mg/kg matrine subcutaneously, respectively, for 7 consecutive days. The tumor was weighed and its volume was measured after the last administration. Single factor analysis of variance was used to compare different groups. The t test was used for pairwise comparison between groups. ResultsIn the control group, the cell structure was normal, the distribution was uniform, and no or rare nuclear pyknosis was seen. With the increase of matrine dosage, the nuclear pyretosis increased gradually and cell morphology changed obviously. Compared with the control group, the cell survival rate in 0.50, 1.00 and 2.00 g/L groups gradually decreased with matrine concentration increasing and treatment time prolongating, the relative expression levels of CyclinD and Bcl-2 mRNA and protein gradually decreased, and the relative expression levels of Bax mRNA and protein gradually increased. Under the same radiation dose X-ray irradiation, the cell survival rate of 0.50, 1.00 and 2.00 g/L groups gradually decreased, and the differences were statistically significant (P＜0.05). Compared with blank group, the tumor weight and volume of mice in different doses of matrine group were significantly decreased, and the differences were statistically significant (P＜0.05). ConclusionMatrine can down-regulate the expression of CyclinD and Bcl-2, up-regulate the expression of Bax, promote the apoptosis of MuM2B human melanoma cells, inhibit cell proliferation, and enhance cell radiosensitivity.
ObjectiveTo summarize the clinical application and future application prospects of organoid model in pancreatic cancer. MethodThe domestic and foreign literature related on the application of organoid model in pancreatic cancer was reviewed. ResultsIn recent years, the organoid model of pancreatic cancer was constructed mainly using patient-derived tissues, fine-needle aspiration samples, and human pluripotent stem cells. The biomarkers of pancreatic cancer were screened according to the histological and structural heterogeneities of the primary tumor retained in organoid model, such as microRNA, glypican-1, annexin A6 and protein biomarkers cytokeratin 7 and 20, cell tumor antigen p53, Claudin-4, carbohydrate antigen 19-9, etc.in the extracellular vesicles. The results of organoid model could maintain the original tumor characteristics and the higher correlation between the organoid model drug sensitivity data and the clinical results of pancreatic cancer patients suggested that, the drug sensitivity data of organoid model could be used to avoid ineffective chemotherapy, so as to improve the treatment response rate and reduce the toxicity of chemical drug treatment, and reasonably select individualized treatment plans for pancreatic cancer patients in future. ConclusionsOrganoid model has many research in screening biomarkers of pancreatic cancer, individualized drug screening, and drug sensitivity test. It can simulate the complex pathophysiological characteristics of pancreatic cancer in vitro, and retain the physiological characteristics and gene phenotype of original tumor cells. It is expected to become a new platform for selecting biomarkers of pancreatic cancer, testing drug sensitivity, and formulating individualized treatment methods for pancreatic cancer, which might further accelerate the research progress of pancreatic cancer.
