ObjectiveTo investigate the condensate pollution in the pipeline of severe pneumonia patients undergoing mechanical ventilation.MethodsFrom January 2017 to January 2019, 120 patients with severe pneumonia treated by mechanical ventilation in our hospital were collected continuously. The lower respiratory tract secretions were collected for bacteriological examination. At the same time, the condensed water in the ventilator exhaust pipe was collected for bacteriological examination at 4, 8, 12, 16, 20 and 24 hours after tracheal intubation and mechanical ventilation. The bacterial contamination in the condensed water at different time points was analyzed and separated from the lower respiratory tract. The consistency of bacteria in secretion and drug resistance analysis of bacterial contamination in condensate water were carried out.ResultsOf the 120 patients with severe pneumonia after mechanical ventilation, isolates were cultured in the lower respiratory tract secretions of 102 patients. One strain was cultured in 88 cases, two strains were cultured in 10 cases, and three strains were cultured in 4 cases. The isolates were mainly Gram-negative bacteria (57.5%) and Gram-positive bacteria (42.5%). The most common isolates were Pseudomonas aeruginosa, Staphylococcus aureus and Acinetobacter baumannii. The contamination rate of condensate water was 5.0% at 4 hours, 37.5% at 8 hours, 60.0% at 12 hours, 76.7% at 16 hours, 95.0% at 20 hours, and 100.0% at 24 hours, respectively. The bacterial contamination rate in condensate water at different time points was statistically significant (P=0.000). The pollution rate at 4 hours was significantly lower than that at 8 hours (P=0.000). Gram-negative bacteria accounted for 57.5% and Gram-positive bacteria accounted for 42.5%. The most common isolates were Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter baumannii. The consistency of bacteria in lower respiratory tract and condensate water was 83.3% in severe pneumonia patients undergoing mechanical ventilation. The overall resistance of Pseudomonas aeruginosa, Acinetobacter baumannii and Staphylococcus aureus was higher, but the resistance to imipenem/cilastatin was lower.ConclusionsThe bacterial contamination in the condensate of patients with severe pneumonia during mechanical ventilation is serious. The pollution rate is low within 4 hours. It is consistent with the bacterial contamination in lower respiratory tract and the bacterial resistance is high.
【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.
Objective To establish a xenograft model of hydroxycamptothecine (HCPT)-resistant human gastric cancer cell line (SGC-7901/HCPT) in nude mice and study its biological characteristics. Methods The SGC-7901 and SGC-7901/ HCPT cells were cultured in vitro. The cell suspension was injected subcutaneously into the nude mice. When the subcutaneous carcinoma was 1.0 cm in diameter, it was cut off and divided into pieces of 0.1-0.2 cm in diameter． Then the small pieces of tumor were re-transplanted subcutaneously into the second generation nude mice until the fourth generation. The morphological feature, ultramicro-structure, and growth characteristics of the fourth generation transplanted tumor were examined. The drug resistance was measured by methyl thiazolyl tetrazolium (MTT) assay. Results The transplanted tumor in nude mice was round or oval, and many blood vessels were on its surface. Under the light microscope, the sizes of SGC-7901 transplanted tumor cells were similar, and sizes of cell nuclei were also similar; Meanwhile, the morphous of SGC-7901/HCPT transplanted tumor cells were irregular and in disorder, and the size of the cell nuclei was different from each other. Under the electron microscope, the mitochondria and endoplasmic reticulum of SGC-7901 transplanted tumor cells were nearly normal and no swelling in cell nuclei; Meanwhile the cell nuclei of SGC-7901/HCPT transplanted tumor cells were lightly swelled, a the mitochondria and endoplasmic reticulum were obviously swelled. By MTT assay, compared with SGC-7901 transplanted tumor cells, the resistance index of SGC-7901/HCPT transplanted tumor cells was 9.02±0.78 in HCPT, and resistance index to Adriamycin， Mitomycin C, 5-fluorouracil, and Etoposide was 1.24±0.09, 1.31±0.17, 0.96±0.12, and 1.07±0.16, respectively. Conclusions A transplanted tumor model of SGC-7901/HCPT in nude mice is established successfully， and showing stable drug resistance to HCPT and no cross-resistance to other chemotherapeutics, which can be used for further experiments.
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 explore the clinical epidemiological characteristics of the lung infection after orthotopical liver transplantation. Methods The clinical data included infection morbidity, mortality, infectious times and relative factors, clinical manifestations, the bacterial strains and distributions of the pathogens, the bacterial resistances of the 53 liver transplantation recipients from 2003.3～2006.12 were summarized and analyzed retrospectively. Results Among 53 recipients, 33 developed lung infectious and 6 died .The mobidity was 62.3% and mortality was 18.2%, with a OR of 1.0. Lung infection predominantly occurred in the first month, especially in the first week after transplantation.There were many factors related to lung infections.Various pathogens, especially Klebsialla, Escherichia Coli and Staphylococus Hominis were isolated from sputum, airway suction drainages and throat swabs. Most of the G- bacteria were sensitive to aminoglycosides,β lactam and lactamase compounds and carbapenems while G+ bacteria were sensitive only to glycopeptides. All the bacteria were resistant to quinolones, β lactams of third and forth generation. Conclusions After liver transplantation, the morbidity and mortality of the lung infections are high.The infections develope at earlier stage, manifest nontypical clinical features.Many factors are revealed to be relevant to the lung infections,meanwhile, various drug-resistant pathogen strains are isolated.
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.
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.
ObjectiveTo provide the evidence for diagnosis and treatment of the complication by describing the distribution and drug sensitivity of pathogens in patients with prosthetic joint infection (PJI) after primary total knee arthroplasty (TKA). MethodsBetween January 2003 and June 2013,65 cases (65 knees) with PJI after primary TKA were treated.There were 28 males and 37 females with an average age of 63.2 years (range,37-80 years).The median interval between PJI and primary TKA was 2.8 years (range,2 weeks to 11 years),including 29 left knees and 36 right knees.Prosthesis loosening could be found in 27 cases by X-ray examination.The average value of C-reactive protein and erythrocyte sedimentation rate was 37.4 mg/L (range,12.5-197.0 mg/L) and 63.2 mm/1 h (range,29.3-73.8 mm/1 h) respectively.Preoperative and intraoperative synovial fluid as well as intraoperative tissue samples should be submitted for aerobic and anaerobic culture.The four types of infections were made according to the Tsukayama et al.classification standards. ResultsThe patients were all diagnosed as having PJI.There were 5(7.69%) type I infections,4(6.15%) type ⅡA,8(12.31%) type ⅡB,3(4.62%) type Ⅲ,and 45(69.23%) type IV according to the Tsukayama et al.classification standard.Bacterial culture results were negative in 12 cases and positive in 53 cases,the main pathogen was Gram-positive cocci (39/53).The most common organism identified was Coagulase-negative Staphylococcus (24/53) followed by Staphylococcus Aureus (12/53).Resistant bacterium accounted for 61.11%(22/36) of Staphylococcus.These bacterium were all sensitive to vancomycin,linezolid,meropenem,and fluconazole;and highly resistant to erythrocin,penicillin,and cefoxitin.The main pathogenic bacteria of Coagulase-negative Staphylococcus and Staphylococcus aureus had highest resistant rate to penicillin. ConclusionGram-positive cocci is the main pathogen in patients with PJI after primary TKA,which is highly resistant to penicillin and macrolides.Antibiotic treatment of this complication should be based on the result of drug sensitivity test,vancomycin and linezolid may be used before the result of drug sensitivity test.It is important to pay attention to rare and multiple resistant bacteria.
ObjectiveTo analyze hepatitis B virus (HBV) genotype distribution and drug-resistant mutations in West China Hospital of Sichuan University, providing basis for hepatitis B individualized treatment.MethodsA total of 786 chronic hepatitis B patients admitted to West China Hospital of Sichuan University from January 2016 to December 2018 were enrolled in the study. Genotype and drug-resistant mutations were analyzed by Sanger sequencing, and statistical analysis was conducted by χ2 test.ResultsThree genotypes (B, C and D) were identified in 786 samples, 489 (62.2%) in genotype B, 291 (37.0%) in genotype C , and 6 (0.8%) in genotype D. The distribution differences of B and C genotypes in age and ethnic groups were statistically significant (P<0.05). Among them, 627 cases had drug-resistant mutations, with a drug-resistant mutation rate of 79.8%. A total of 262 cases (33.3%) were resistant to lamivudine and tibivudine, 102 cases (13.0%) were resistant to lamivudine, tibivudine and entecavir; 83 cases (10.6%) were resistant to adefovir dipivoxil. No tenofovir resistant strains were detected in 786 samples. There were statistically significant differences in drug resistance between B and C genotypes (χ2=14.356, P<0.01). The most common single mutation was M204I [179 cases (22.8%)], followed by 46 cases (5.9%) of A181V/T associated with adefovir dipivoxil resistance. The most common mixed mutation was L180M+M204V/I in 83 cases (10.6%), and another 102 cases (13.0%) showed M250V and/or V173L and/or T184A/G/S/I and/or S202G/I with L180M+M204V/I.ConclusionsHBV genotypes in West China Hospital of Sichuan University are mainly B and C, and the situation of drug resistance is severe and the mutation pattern is complex. Therefore, detecting HBV genotype and drug resistance mutation is necessary, which may develop better clinical treatments.
Objective To investigate the clinical manifestations,diagnosis and treatment of extensively drug-resistant tuberculosis (XDR-TB)meningitis. Methods One case of primary tuberculousis meningitis infected with multidrug-resistant mycobacteria was analyzed retrospectively.Relevant literatures were also reviewed by retrieving information through Wanfang Database and Pubmed using key words "multiple drug resistant tuberculosis meningitis","MDR tuberculosis meningitis","multiple drug resistant TBM","mul-drug resistant tuberculous meningitis","extensively drug resistant tuberculosis meningitis","XDR TBM","extensively drug resistant TBM" both in Chinese and English. Results A 24-year-old male patient,complained of headache,vomiting for 5 days,aggravated with mental abnormalities for 10 hours,with no history of pulmonary tuberculosis,was hospitalized in the Affiliated Hospital of Zunyi Medical College.The chest plain film was normal.Craniocerebral CT scan showed mild-hydrocephalus and cisterna ambiens stenosis.The patient died after undergoing anti-TB treatments with isoniazid(INH)0.3g iv qd,INH 0.3g po qd,rifampicin(RFP)0.45g qd,pyrazinamide(PZA)1.5g qd,ethambutol(EMB)0.75g qd,and dexamethasone(DEX)15mg qd.He was diagnosed as XDR-TB meningitis(as drug-resistant to isoniazid,rifampicin,streptomycin,ciprofloxacin,paminosalicylic acid,kanamycin,and protionamide ).Mycobacteria tuberculosis was isolated from his cerebrospinal fluid after 3 months.Five cases in 4 literatures were retrieved through Wanfang database and Pubmed among which 2 cases were initial treated,3 cases was unknown about initial treatment or re-treatment. Conclusions XDR-TB meningitis is rare in clinical practice with serious condition,rapid progress and high mortality rate.It is necessary to acquire drug susceptibility test results as soon as possible and adjust treatments according different conditions.A molecular drug susceptibility test may be helpful in the future.