Peptidoglycan is an important component of bacterial cell wall, which plays an important role in maintaining the integrity of bacterial cell structure, stimulating immune response, and anti-infection. Peptidoglycan recycling is an indispensable process for bacterial cell growth and reproduction. In recent years, it has been reported that the peptidoglycan recycling is closely related to the occurrence and development of bacterial resistance, especially with the antibacterial activity of β-lactam antibiotics. In this paper, the relationship between peptidoglycan recycling and resistance is described by combining relevant reports and taking Mycobacterium tuberculosis and Pseudomonas aeruginosa as examples, so as to promote the understanding of bacterial resistance mechanisms and provide potential targets for the development of new antimicrobial drugs.
ObjectiveTo explore the effects of different exercise methods on serum short-chain fatty acids (SCFA) in type 2 diabetic mice, determine the best exercise method to improve SCFAs in type 2 diabetic mice, and provide a theoretical basis for the preventive intervention for patients with early diabetes.MethodsAccording to different exercise methods, 48 8-week-old male db/db type 2 diabetic mice were randomly divided into four groups, including aerobic exercise group, resistance exercise group, combined resistance- aerobic exercise (referred to as combined exercise) group, and the control group; with 10 mice in each group and another 2 as the substitutes. The mice were fed in the same manner in each group. The control group did not perform exercise intervention, the aerobic exercise group performed weightless running exercise, the resistance exercise group performed tail weight-bearing ladder exercise, and the combined exercise group alternated aerobic exercise and resistance exercise. Blood glucose and body weight were measured before and 8 weeks after the intervention. The content of serum SCFAs in mice was determined by gas chromatography-mass spectrometry.ResultsA total of 40 mice completed the experiment successfully. Before the exercise intervention, there was no significant difference in blood glucose or weight among the groups (P>0.05). After 8 weeks of exercise intervention, the blood glucose and weight in each exercise group were significantly lower than those in the control group (P<0.05), and the blood glucose and weight in the combined exercise group were significantly lower than those in the aerobic exercise group and the resistance exercise group (P<0.05). The contents of SCFA were higher in the aerobic exercise group, resistance exercise group, and combined exercise group than those in the control group (P<0.05); the contents of acetic acid and butyric acid in the combined exercise group were better than those in the aerobic exercise group (P<0.05), and the contents of propanoic acid and valeric acid in the combined exercise group were better than those in the resistance exercise group (P<0.05).ConclusionsDifferent exercise methods can improve the SCFA content in serum of type 2 diabetic mice. Compared with aerobic exercise and resistance exercise, combined exercise has the best effect in improving SCFA.
Objective To summarize the development of gallbladder carcinoma related resistance genes and targeted therapy. Methods Domestic and international publications online involving resistance genes and targeted therapy of gallbladder carcinoma in recent years were collected and reviewed. Results Recent studies had shown that chemotherapy drug resistance of gallbladder carcinoma mainly involved lysosome protein transmembrane β4 （LAPTM4B） gene， NF-E2-related factor 2 （Nrf2） gene， and cancer stem cells （CSCs）. While the latest gene targets of treatment for gallbladder carcinoma mainly involved LAPTM4B， Nemo-like kinase （NLK）， tissue factor way inhibitor-2 （TFPI-2）， vascular endothelial growth factor-D （VEGF-D）， epidermal growth factor receptor （EGFR）， and melanoma differentiation-associated gene 7/interleukin 24 （mda-7/IL-24） gene. Conclusion The research involving resistance genes and targeted therapy of gallbladder carcinoma has make a certain progress， which broaden the concept of traditional treatment of gallbladder carcinoma.
Objective To introduce the research progress in the effect of chemotherapeutic resistance of metabolic enzymes of gemcitabine to pancreatic cancer.Methods Recent literatures about metabolic enzymes that played key roles in mediating gemcitabine chemotherapeutic resistance of pancreatic cancer were collected and reviewed. Results The metabolic enzymes of gemcitabine, such as hENT1, dCK, RRM1 and CDA, were closely related to chemotherapeutic resistance of pancreatic cancer. The relationship between the single nucleotide polymorphism of metabolic enzymes and the resistance to gemcitabine remained to be clarified. Conclusion Multiple factors are involved in the mechanism of chemotherapeutic resistance of pancreatic cancer to gemcitabine, which needs further research.
ObjectiveTo analyze and summarize the clinical characteristics, risk factors, pathogenic bacteria type, and drug tolerance of diabetes complicated with hospital-acquired pulmonary infection, in order to reduce the incidence of hospital-acquired pulmonary infection in patients with diabetes. MethodsThe clinical data of diabetic patients with hospital-acquired pulmonary infection from 2011 to 2013 were taken for retrospective clinical analysis. ResultsA total of 78 diabetic patients had hospital-acquired pulmonary infection among all the 572 hospitalized patients with diabetes. Age, complications of diabetes, chronic underlying disease, duration of hospital stay, glycated hemoglobin and invasive procedures were all correlated with the incidence of hospital-acquired infection (P<0.05). Through sputum culture and throat culture, 59 strains of pathogens were found, and they were mainly multidrug-resistant Gram-negative bacteria, accounting for 71.2%. ConclusionThe rate of acquired pulmonary infection in diabetic patients is particularly high, and the pathogens are mostly Gram-negative and multidrug-resistant. Glycemic control, rational use of antimicrobial drugs, shorter hospital stay, effective prevention and treatment of diabetes complications and chronic underlying diseases, and aseptic techniques can be effective in preventing acquired pulmonary infection for diabetic patients.
ObjectiveTo explore the risk factors for neonatal nosocomial infection and the pathogen resistance, in order to provide the basis for hospital infection control. MethodsSurveillance of hospital infection in newborns hospitalized for more than 48 hours were carried out from January to December 2012, and the risk factors for hospital infection were analyzed. ResultsThere were 54 newborn cases with neonatal nosocomial infection, and the infection rate of newborns was 1.25%. The major infection sites were respiratory tract (66.7%), gastrointestinal tract (18.5%), skin and soft tissues (9.2%). Birth weight (χ2Trend=126.88, P<0.001), hospitalization days (χ2Trend=106.89, P<0.001), invasive operation (χ2=5.338, P=0.021) were the major risk factors. A total of 54 strains of pathogenic bacteria were isolated from 54 newborn cases with neonatal nosocomial infection. Twenty-three strains of gram-positive bacteria accounted for 42.6%, which were generally resistant to penicillin and large ring lactone class antibiotic drugs. Thirty-one strains of gram-negative bacteria accounted for 57.4%, which were mainly resistant to the three generations of cephalosporins. ConclusionThe hospital infection rate of newborns is low. Birth weight, hospitalization days and invasive operation are the major risk factors for neonatal nosocomial infection.
Objective To analyze the species distribution and resistance of the pathogens isolated fromblood cultures of the patients in intensive care unit ( ICU) , and provide a basis for prevention and control of bloodstream infections in critically ill patients. Methods The data of blood cultures of the patients in ICUduring January 2009 to December 2011 was investigated retrospectively.Results In the last 3 years, positive rate of blood cultures of ICU patients was 15. 4% , 15. 7% , and 17. 6% respectively. Among the isolates, Gram-positive bacteria were predominant ( 52. 3% ) , followed in order by gram-negative bacteria ( 33. 1% ) and fungi ( 14. 7% ) . Aerobe and facultative anaerobe were the predominant bacterial isolates ( 99. 7% ) . Enterococcus faeciumand Staphylococcus spp. were the most common gram-positive bacteria, and 4. 5% of E. faecium isolates were resistant to vancomycin. Rate of methicillin-resistance for S. aureus and S. epidermidis was 73. 5% and 93. 7% respectively. In terms of gram-negative bacteria, Acinetobacter calcoaceticus- A. baumannii complex were the leading species, 96. 9% of the isolates had multi-drug resistance and 14. 1% of the isolates had extra-drug resistance. Klebsiella pneumonia and Escherichia coli isolates were less frequently isolated and those producing extended spectrum beta-lactamases accou ted for 70. 3% and 80. 0% of the isolates respectively. Candida spp. was the most common fungi isolates ( 96. 7% )with an annual change of species distribution and declining susceptibility to azoles.Conclusions Gram-positive bacteria should be the major target for prevention and control of bloodstream infections in critically ill patients. Whereas, more attention should be paid to the infection caused by candida spp. and multidrug resistant gram-negative bacteria.
ObjectiveTo investigate the species and resistance phenotypes of the pathogens causing catheter-associated urinary tract infection (CAUTI) in critically ill patients in West China Hospital of Sichuan University, and to provide the basis for the prevention and treatment of this kind of infection. MethodsThe clinical data and findings of the laboratory examination of the patients, who were admitted to intensive care units and suffered from CAUTI in our hospital during January 2012 to December 2014, were retrospectively analyzed. The pathogens isolates from the urine specimens of the patients with CAUTI and their resistance phenotypes were analyzed. ResultsThree hundred and seventy patients suffering from CAUTI were included in this study. Five hundred and seventeen strains of pathogens were isolated from the urine specimens of these patients, including 222 isolates (42.9%) of fungus, 181 isolates (35.0%) of gram negative bacteria, and 114 isolates (22.0%) of gram positive bacteria. In terms of species distribution, Candida albicans (105 isolates, 20.3%), C.glabrata (78 isolates, 15.1%) and C.glabrata (30 isolates, 5.8%) were the predominant fungus. Among the gram negative bacteria, Escherichia coli (81 isolates, 15.7%), Klebsiella pneumoniae (37 isolates, 7.2%), and Acinetobacter calcoaceticus-baumannii complex (23 isolates, 4.4%) were the main species. Enterococcus faecium (79 isolates, 15.3%) and E.faecalis (13 isolates, 2.5%) were the frequently isolated gram positive bacteria. Analysis of the resistance phenotype showed that the resistance rates to itraconazole, voriconazole and fluconazole of Candida spp. were above 10%. Thirty percent of the isolates of E.coli and K.pneumoniae, and 60% of the isolates of A.calcoaceticus-Baumannii complex were resistant to many of the regular antibiotics. Imipenem resistance rate of A.calcoaceticus-Baumannii complex was 60.8%. Sixty percent of the isolates of E.faecium and E.faecalis were resistant to many of the regular antibiotics. The vancomycin-resistant isolates accounted for 16.5% of E.faecium and 31.0% of E.faecalis. ConclusionCandida species are the major pathogens for CAUTI in critically ill patients in our hospital and show the resistance to azoles. We should focus on the drug resistance of gram negative bacteria and gram positive bacteria. The rational use of antibiotics and application of effective infection control measures are important to decrease the CAUTI.
ObjectiveTo investigate the distribution and drug resistance of Acinetobacter baumannii (AB) in a women and children's hospital. MethodsStrains of AB isolated from clinical specimens between January 2011 and December 2013 were identified with Vitek2-compact microbiology analyzer; antimicrobial susceptibility test was performed by Kirby-Bauer disk diffusion method. The resistant rate, intermediate rate and susceptibility rate of drugs were calculated according to the criteria in guidelines of Clinical and Laboratory Standards Institute. WHONET 5.6 software was used to analyze the data. ResultsA total of 167 strains of AB were isolated and tested. Neonatal ward had the highest detection proportion. Most strains of AB were isolated from sputum. The drug resistance rate of AB to piperacillin tazobactam, cefepime and carbapenem was<25%. ConclusionThe drug sensitivity rate of AB to piperacillin/tazobactam, cefepime and carbapenems was high, but drug resistence to antimicrobial drugs increased continuously in three years. Medical institutions should strengthen the monitoring of AB resistance, implement rational use of antibiotics, and carry out hand hygiene education, to reduce the generation and dissemination of AB resistant strains.
ObjectiveTo understand the clinical distribution and drug resistance of Klebsiella pneumoniae in Yibin during 2011 to 2014 so as to provide evidence for clinical rational use of antimicrobial drugs. MethodsKlebsiella pneumoniae isolated from all types of clinical specimens were collected from the First People's Hospital and the Second People's Hospital of Yibin during 2011 to 2014. VITEK2 Compact and its supporting identification card GP and drug sensitivity test card AST-GP67 were used for detection, and the results were analyzed and summarized. ResultsMost Klebsiella pneumoniae were detected from the Department of Respiratory Medicine, the proportion for each year was 48.15%, 46.24%, 45.44%, and 44.97% during 2011 to 2014. Klebsiella pneumoniae isolated were mainly from sputum samples, the proportion for each year was 81.01%, 89.18%, 87.80%, and 83.52% between 2011 and 2014. Imipenem and piperacillin/tazobactam resistance rates were lower, but the overall trend was rising. Ampicillin/sulbactam, and sulfamethoxazole resistance rates were higher. Levofloxacin, ciprofloxacin increased year by year. Aztreonam, cefepime, and amikacin rate declined. ConclusionKlebsiella pneumoniae is one of the main infection pathogen in the Department of Respiratory Medicine. Klebsiella pneumoniae resistance rates are higher. Klebsiella pneumoniae were sensitive to enzyme inhibitors β-lactam antimicrobial agents and carbapenem antibiotics.