1.Effect of melatonin on proliferation and apoptosis of fibroblasts in human hypertrophic scar.
You-fu XIE ; Jun-cheng ZHANG ; Si-jun LIU ; Li-bing DAI ; Gao-wei DU
Chinese Journal of Burns 2011;27(6):422-426
OBJECTIVETo study the effect of melatonin on proliferation and apoptosis of fibroblasts in human hypertrophic scar and its mechanism.
METHODSFibroblasts from human hypertrophic scar were isolated and cultured with DMEM medium containing 10% FBS, and then they were divided into control (C, added with ethanol), low concentration (LC, added with 1 × 10(-5) mmol/L melatonin), middle concentration (MC, added with 1 × 10(-3) mmol/L melatonin), and high concentration (HC, added with 1 mmol/L melatonin) groups according to the random number table. After being cultured for 24 hours, cell morphologic change was observed under microscope; XTT-PMS assay was used to examine cell proliferative activity; cell cycle and apoptosis were assessed with flow cytometry after double staining of FITC and PI, and the levels of cyclin E, p53, and Fas mRNA were determined with fluorescence quantitative RT-PCR. Data were processed with analysis of variance and LSD test.
RESULTS(1) Fibroblasts in C group were spindle-shaped with growth in colonies. Along with the increase in melatonin concentration, fibroblasts in LC, MC, and HC groups gradually dispersed, deformed and atrophied, with shrunk cellular membrane, and decrease in ratio of nucleus and cytoplasm. (2) Proliferative activity of fibroblasts in LC, MC, and HC groups decreased along with an increase in melatonin concentration (1.49 ± 0.15, 1.24 ± 0.20, and 0.92 ± 0.09), which were lower that in C group (1.79 ± 0.10, F = 67.61, P < 0.05). Cell ratios of S and G2/M phases in LC, MC, and HC groups decreased along with an increase in melatonin concentration, which were all lower than those in C group [(10.6 ± 1.1)%, (6.1 ± 1.2)%, (3.2 ± 0.8)% vs.(16.9 ± 1.3)%, F = 286.10, P < 0.05; (13.5 ± 1.1)%, (9.8 ± 1.0)%, (6.0 ± 0.7)% vs. (16.7 ± 1.6)%, F = 162.69, P < 0.05]. Apoptotic rates in early and late stages of LC, MC, and HC groups increased along with an increase in melatonin concentration, all higher than those in C group (with F value respectively 424.05, 236.44, P values all below 0.05). The expressions of cyclin E mRNA in LC, MC, and HC groups decreased along with an increase in melatonin concentration, which were lower than that in C group (1.58 ± 0.21, 0.90 ± 0.20, and 0.24 ± 0.12 vs. 2.90 ± 0.30, F = 266.79, P < 0.05), while the expressions of p53 mRNA and Fas mRNA showed opposite tendency (with F value respectively 10.11, 12.03, P values all below 0.05).
CONCLUSIONSMelatonin can inhibit proliferation and induce apoptosis of fibroblasts in hypertrophic scar through regulating the gene expressions of cyclin E, p53, and Fas.
Adult ; Apoptosis ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Cicatrix, Hypertrophic ; metabolism ; pathology ; Cyclin E ; metabolism ; Female ; Fibroblasts ; drug effects ; metabolism ; pathology ; Humans ; Male ; Melatonin ; pharmacology ; Oncogene Proteins ; metabolism ; Tumor Suppressor Protein p53 ; metabolism ; fas Receptor ; metabolism
2.The Prognostic Value of 18F-Fluorodeoxyglucose PET/CT in the Initial Assessment of Primary Tracheal Malignant Tumor: A Retrospective Study
Dan SHAO ; Qiang GAO ; You CHENG ; Dong-Yang DU ; Si-Yun WANG ; Shu-Xia WANG
Korean Journal of Radiology 2021;22(3):425-434
Objective:
To investigate the potential value of 18F-fluorodeoxyglucose (FDG) PET/CT in predicting the survival of patients with primary tracheal malignant tumors.
Materials and Methods:
An analysis of FDG PET/CT findings in 37 primary tracheal malignant tumor patients with a median follow-up period of 43.2 months (range, 10.8–143.2 months) was performed. Cox proportional hazards regression analyses were used to assess the associations between quantitative 18F-FDG PET/CT parameters, other clinic-pathological factors, and overall survival (OS). A risk prognosis model was established according to the independent prognostic factors identified on multivariate analysis. A survival curve determined by the Kaplan-Meier method was used to assess whether the prognosis prediction model could effectively stratify patients with different risks factors.
Results:
The median survival time of the 37 patients with tracheal tumors was 38.0 months, with a 95% confidence interval of 10.8 to 65.2 months. The 3-year, 5-year and 10-year survival rate were 54.1%, 43.2%, and 16.2%, respectively. The metabolic tumor volume (MTV), total lesion glycolysis (TLG), maximum standardized uptake value, age, pathological type, extension categories, and lymph node stage were included in multivariate analyses. Multivariate analysis showed MTV (p = 0.011), TLG (p = 0.020), pathological type (p = 0.037), and extension categories (p = 0.038) were independent prognostic factors for OS. Additionally, assessment of the survival curve using the Kaplan-Meier method showed that our prognosis prediction model can effectively stratify patients with different risks factors (p < 0.001).
Conclusion
This study shows that 18F-FDG PET/CT can predict the survival of patients with primary tracheal malignant tumors. Patients with an MTV > 5.19, a TLG > 16.94 on PET/CT scans, squamous cell carcinoma, and non-E1 were more likely to have a reduced OS.
3.Controlled clinical trials of initial observation on therapeutic effects of moxibustion for osteoarthritis of the knee: multi-center clinical effect.
Jia-Can SU ; Lie-Hu CAO ; Zhuo-Dong LI ; Si-Cheng WANG ; Qian-Jin ZHANG ; Yu-Hai MA ; Xiao-Ming FU ; Bao-Qing YU ; Ning DU ; Chun-Cai ZHANG
China Journal of Orthopaedics and Traumatology 2009;22(12):914-916
OBJECTIVETo compare therapeutic effects between moxibustion and infrared therapy for the treatment of knee osteoarthritis.
METHODSFrom January 2007 to June 2008 period, 65 patients with knee osteoarthritis were divided into treatment and control groups randomly uniform random number table generated from SAS statistical software. Among 35 patients in the treatment group, 17 patients were male and 18 patients were female, ranging in age from 45 to 75 years, with an average of (61.2+/-6.4) years; the course of disease ranged from 9 to 43 months, with a mean of (23.6+/-13.8) months; the preoperative Lysholm score ranged from 19 to 28 scores, averaged (24.3+/-3.3) scores. In the control group, there were 30 patients, including 13 males and 17 females, ranging in age from 47 to 79 years, with an average of (62.5+/-9.3) years; the course of disease ranged from 8 to 45 months, with a mean of (24.6+/-16.6) months; the preoperative Lysholm score ranged from 20 to 29 scores, averaged (25.9+/-3.0) scores. The patients in the treatment group were treated with moxibustion, and the patients in control group were treated with infrared therapy. All the patients were followed up for 4 weeks. The Lysholm scores were compared between the two groups.
RESULTSAccording to Lysholm score for clinical efficacy, treatment group got (87.5+/-5.6) scores and the control group were (85.9+/-3.5) scores, the Lysholm score of the treatment group was higher than that of the control group (P<0.05). Among pain score, joint flexion and extension score, joint stability score, and up and down stairs score, the pain and joint stability scores of patients in the treatment group were higher than those of control group (P<0.05).
CONCLUSIONCompared with infrared therapy, moxibustion treatment for knee osteoarthritis can get better joint function, which is effect to alleviate the patient's pain, improve joint stability, improve the efficacy, and is valued to be promoted.
Aged ; Female ; Humans ; Male ; Middle Aged ; Moxibustion ; methods ; Multicenter Studies as Topic ; Osteoarthritis, Knee ; therapy ; Treatment Outcome
4.Evaluation of the clinical effect of knee osteoarthritis treated with moxibustion according to WHOQOL-BREF.
Lie-Hu CAO ; Si-Cheng WANG ; Qian-Jin ZHANG ; Zhuo-Dong LI ; Yu-Hai MA ; Jia-Can SU ; Ning DU
China Journal of Orthopaedics and Traumatology 2009;22(11):813-815
OBJECTIVETo investigate and research WHOQOL-BREF evaluation of the clinical effect of application of moxibustion for treatment of knee osteoarthritis, to provide clinical according for the treatment.
METHODSFrom January 2007 to June 2008, 90 cases of knee osteoarthritis were randomly divided into treatment group and control group. In treatment group there were 45 cases included 16 males and 29 females with an average age of (62.5 +/- 7.4) years; the average course was (26.5 +/- 14.6) months; Lysholm score of knee function before treatment was (65.5 +/- 3.5) hours on average. In control group, there were 45 cases included 11 males and 34 females with an average age of (62.5 +/- 9.3) years;the average course was (24.6 +/- 16.6) months; Lysholm score of knee function before treatment was (66.3 +/- 2.3) hours on average. Applied Quality of Life Scale WHOQOL-BREF in line with the inclusion criteria of the study evaluation. While applied Lysholm scoring of knee joint for supporting the evaluation criteria. All data were statistical analyzed by package SPSS 11.5.
RESULTSMoxibustion was applied to treat the knee osteoarthritis and the quality of life was evaluated according to the WHOQOL-BREF scale score. The scores of the physical state, psychological state, as well as their own general health status of subjective feeling, and so on in treatment was significantly higher than that in control group (P < 0.05). According to Lysholm scoring, the score in treatment group was significantly higher than that of control group, too (t = 0.65, P < 0.05).
CONCLUSIONApplication of moxibustion for treatment of knee osteoarthritis is a simple, economical and practical, and can avoid the further development of the disease, but also to improve the joint function and improve quality of life.
Aged ; Female ; Humans ; Male ; Middle Aged ; Moxibustion ; Osteoarthritis, Knee ; pathology ; physiopathology ; therapy ; Quality of Life ; Treatment Outcome ; World Health Organization
5.Neurosonographic characteristics of peripheral nerve in transthyretin familial amyloid polyneuropathy
Ke XU ; Kang DU ; Si CHENG ; Haiying XING ; Yun YUAN ; Yining HUANG ; Lingchao MENG
Chinese Journal of Neurology 2022;55(6):589-596
Objective:To study peripheral nerve morphology in patients with transthyretin familial amyloid polyneuropathy (TTR-FAP) using high-frequency ultrasonography (HFUS), and to evaluate the value of HFUS in diagnosis of TTR-FAP.Methods:Thirty-eight patients with TTR-FAP diagnosed by gene detection and 23 normal controls from June 2015 to June 2021 in Peking University First Hospital were enrolled in this study. Consecutive ultrasonography scanning was performed in 6 pairs of nerves of bilateral limbs with 30 sites. The cross sectional area (CSA), CSA variability and inter-nerve CSA variability data of the two groups were retrospectively calculated and compared.Results:Compared with the normal controls, TTR-FAP patients showed larger CSA values at most nerve sites of both upper and lower limbs, and there were statistically significant differences at M1(median nerve) [8.55 (6.90, 9.40) mm 2vs 10.05 (9.10, 14.10) mm 2, Z=5.58, P<0.001], M3 (median nerve) [(6.98±1.66) mm 2vs (9.29±2.30) mm 2, t=6.28, P<0.001], M5 (median nerve) [(8.91±1.81) mm 2vs (14.33±4.20) mm 2, t=9.84, P<0.001], U5 (ulnar nerve) [(6.20±1.93) mm 2vs (9.34±2.85) mm 2, t=7.31, P<0.001], Sci1 (sciatic nerve) [(53.50±17.24) mm 2vs (79.74±20.75) mm 2, t=7.57, P<0.001], Sci2 (sciatic nerve) [(53.66±14.21) mm 2vs (73.98±19.21) mm 2, t=6.82, P<0.001] and Tib (tibial nerve) [(31.05±8.43) mm 2vs (46.29±13.14) mm 2, t=7.84, P<0.001] sites. There was no statistically significant difference in CSA at each site among the different subtypes and disease severity of TTR-FAP patients ( P>0.05). There was no statistically significant difference in CSA-variability of the median and ulnar nerves between the patients with TTR-FAP and the normal controls ( P>0.05). The side-to-side difference ratio of intra-nerve CSA variability of the ulnar nerve in the patients with TTR-FAP was smaller than that of the normal controls (1.15±0.10 vs 1.46±0.43, t=3.43, P=0.002), whereas no statistically significant difference of that in the median nerve was found between the two groups ( P>0.05). Conclusions:The most pronounced peripheral nerve thickening in the proximal limb segments with no signs of asymmetric distribution or lateralization is confirmed by HFUS in TTR-FAP patients and should be regarded as a marker of TTR-FAP. HFUS has clinical value in diagnosis of peripheral neuropathy in TTR-FAP patients.
6.Prognostic value of baseline C-reactive protein levels in patients undergoing coronary revascularization.
Xu LI ; Xiao-Hui LIU ; Shao-Ping NIE ; Xin DU ; Qiang LÜ ; Jun-Ping KANG ; Jian-Zeng DONG ; Cheng-Xiong GU ; Fang-Jiong HUANG ; Yu-Jie ZHOU ; Fang CHEN ; Shu-Zheng LÜ ; Xue-Si WU ; Chang-Sheng MA
Chinese Medical Journal 2010;123(13):1628-1632
BACKGROUNDC-reactive protein (CRP) is a lowly expressed marker for inflammatory response. This study aimed to evaluate the prognostic value of baseline CRP levels in patients undergoing coronary revascularization in the context of modern medical treatment.
METHODSThis was a retrospective study in a single center. Four hundred and fourteen patients were enrolled, who underwent coronary revascularization and received adequate medication for secondary prevention of coronary heart disease. The study compared the follow-up clinical outcomes between high level CRP group (CRP > 5 mg/L) and low level one. The median follow-up time was 551 days.
RESULTSCompared with low CRP group, the relative risk (RR) of the major adverse cardiovascular and cerebral events (MACCE) in high CRP group was 5.131 (95%CI: 1.864-14.123, P = 0.002). There were no significant differences in death, myocardial infarction and stroke during the follow-up between two groups, but a higher risk of re-revascularization was found in high CRP group (RR 6.008, 95%CI: 1.667-21.665, P = 0.006). Cox regression analysis showed that only CRP level could contribute to MACCE during the follow-up. MACCE-free rate was much lower in high CRP group (Kaplan-Meier log-rank P < 0.001).
CONCLUSIONIn the context of modern medical treatment, the baseline level of CRP is an independent predictor for long-term prognosis in patients with coronary revascularization.
Aged ; C-Reactive Protein ; metabolism ; Coronary Disease ; metabolism ; surgery ; Female ; Humans ; Male ; Middle Aged ; Myocardial Revascularization ; methods ; Retrospective Studies
7.Coronary stenting versus bypass surgery in heart failure patients with preserved ejection fraction.
Zeng-ming XUE ; Wei-ju LI ; Chang-sheng MA ; Shao-ping NIE ; Jian-zeng DONG ; Xiao-hui LIU ; Jun-ping KANG ; Qiang LÜ ; Xin DU ; Xiao WANG ; Fang CHEN ; Yu-jie ZHOU ; Shu-zheng LÜ ; Fang-jiong HUANG ; Cheng-xiong GU ; Xue-si WU
Chinese Medical Journal 2012;125(6):1000-1004
BACKGROUNDThe optimal revascularization strategy in patients with heart failure with preserved ejection fraction (HFPEF) remains unclear. The aim of the present study was to compare the effects of percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) in patients with HFPEF.
METHODSFrom July 2003 through September 2005, a total of 920 patients with coronary artery disease (CAD) and HFPEF (ejection fraction ≥ 50%) underwent PCI (n = 350) or CABG (n = 570). We compared the groups with respect to the primary outcome of mortality, and the secondary outcomes of main adverse cardiac and cerebral vascular events (MACCE), including death, myocardial infarction, stroke and repeat revascularization, at a median follow-up of 543 days.
RESULTSIn-hospital mortality was significantly lower in the PCI group than in the CABG group (0.3% vs. 2.5%, adjusted P = 0.016). During follow-up, there was no significant difference in the two groups with regard to mortality rates (2.3% vs. 3.5%, adjusted P = 0.423). Patients receiving PCI had higher MACCE rates as compared with patients receiving CABG (13.4% vs. 4.0%, adjusted P < 0.001), mainly due to higher rate of repeat revascularization (adjusted P < 0.001). Independent predictors of mortality were age, New York Heart Association (NYHA) class and chronic total occlusion.
CONCLUSIONAmong patients with CAD and HFPEF, PCI was shown to be as good as CABG with respect to the mortality rate, although there was a higher rate of repeat revascularization in patients undergoing PCI.
Aged ; Angioplasty, Balloon, Coronary ; mortality ; Coronary Artery Bypass ; mortality ; Female ; Heart Failure ; physiopathology ; therapy ; Hospital Mortality ; Humans ; Male ; Middle Aged ; Stents
8.Multicenter epidemiological characteristics of Mycoplasma pneumoniae infection in children in Hainan Province, 2012-2020
LIAO Shang-qiu ; TAN Hui ; ZHANG Xue-mei ; WAN Ke-cheng ; LU Xiong-fu ; ZHU Hou-cai ; YANG Zi-jiang ; ZHANG Yu-qing ; LIU Jia-yu ; TAN Xiao-yu ; DU Yu-ang ; BAI En-xu ; CAI Si-ming ; HUO Kai-ming
China Tropical Medicine 2023;23(5):511-
Abstract: Objective To analyze the epidemiological characteristics (season, age, gender, mixed infection and clinical manifestations, etc.) of Mycoplasma pneumoniae (MP) infection in children in Hainan Province, so as to provide epidemiological evidence-based medical basis for the prevention and control of MP infection in children in Hainan Province. Methods The serum IgM antibodies of MP, Legionella pneumophila, Chlamydia pneumoniae, adenovirus, respiratory syncytial virus (RSV), Q fever Rickettsia, parainfluenza virus, influenza A virus and influenza B virus in children with respiratory tract infections (RTIs) who were hospitalized in pediatrics of many hospitals in Hainan Province from March 2012 to February 2020 were detected by indirect immunofluorescence method. The positive serum MP-IgM antibody was defined as MP infection. The epidemiological and clinical data of MP infected cases were analyzed retrospectively. Results From March, 2012 to February, 2020, a total of 35 731 qualified pediatric inpatients with RTIs in many hospitals in Hainan Province were tested for serum MP-IgM with the total positive rate of 39.12% (13 978/35 731). The yearly positive rates of MP-IgM from 2012 to 2020 were 48.39%, 56.23%, 56.62%, 47.04%, 29.71%, 24.14%, 47.55%, 36.84% and 24.46% respectively. The positive rates of MP-IgM in 2013 and 2014 were significantly higher than those in other years (P<0.05). The positive rate of MP-IgM in summer in Hainan Province was the highest (41.34%) and the lowest in winter (35.77%) (P<0.05). MP infection occurred in all age groups, the positive rate of MP-IgM in children of preschool (51.80%) was significantly higher than that in other age groups (P<0.01), and the positive rate of MP IgM in children of infancy (15.36%) was lower than that in other age groups (P<0.01). The positive rate of MP-IgM in female was 44.77%, which was significantly higher than that in male (35.83%) (P<0.05). MP infection combined with positive IgM of another pathogen accounted for 32.63% (4 561 cases), positive IgM of another two pathogens accounted for 1.26% (176 cases). MP infection was mostly found in pneumonia (68.73%), and the main clinical symptoms were cough (84.72%), fever (51.01%) and wheezing (3.16%). Conclusions MP is an important pathogen of respiratory tract infection in children in Hainan Province, and infection is more common in children in early school age and early childhood. Mp-specific tests should be performed to identify the pathogen in children suspected of MP infection. In the high incidence season, health education should be strengthened in kindergartens, schools and other places to prevent respiratory tract infection.
9.Preliminary molecular epidemiology of the Staphylococcus aureus in lower respiratory tract infections: a multicenter study in China.
De-Zhi LI ; Yu-Sheng CHEN ; Jing-Ping YANG ; Wei ZHANG ; Cheng-Ping HU ; Jia-Shu LI ; Lan MU ; Ying-Hui HU ; Rong GENG ; Ke HU ; Shao-Xi CAI ; Huan-Ying WAN ; Qiu-Yue WANG ; Li-Ping WEI ; Juan DU ; Qin YU ; Xiao-Ning ZHONG ; Rui-Qin WANG ; Jian-Jun MA ; Gui-Zhen TIAN ; Si-Qin WANG ; Zhan-Cheng GAO
Chinese Medical Journal 2011;124(5):687-692
BACKGROUNDStaphylococcus aureus (S. aureus) remains as an important microbial pathogen resulting in community and nosocomial acquired infections with significant morbidity and mortality. Few reports for S. aureus in lower respiratory tract infections (LRTIs) have been documented. The aim of this study was to explore the molecular epidemiology of S. aureus in LRTIs in China.
METHODSA multicenter study of the molecular epidemiology of S. aureus in LRTIs was conducted in 21 hospitals in Beijing, Shanghai and twelve other provinces from November 2007 to February 2009. All the collected S. aureus strains were classified as minimum inhibitory concentration (MIC), mecA gene, virulence genes Panton-Valentine Leukocidin (PVL) and γ-hemolysin (hlg), staphylococcal cassette chromosome mec (SCCmec) type, agr type, and Multilocus Sequence Typing (MLST).
RESULTSTotally, nine methicillin-sensitive S. aureus (MSSA) and 29 methicillin-resistant S. aureus (MRSA) strains were isolated after culture from a total of 2829 sputums or bronchoalveolar lavages. The majority of MRSA strains (22/29) had a MIC value of ≥ 512 µg/ml for cefoxitin. The mecA gene acting as the conservative gene was carried by all MRSA strains. PVL genes were detected in only one S. aureus strain (2.63%, 1/38). The hlg gene was detected in almost the all S. aureus (100% in MSSA and 96.56% in MRSA strains). About 75.86% of MRSA strains carried SCCmec III. Agr type 1 was predominant (78.95%) among the identified three agr types (agr types 1, 2, and 3). Totally, ten sequence type (ST) of S. aureus strains were detected. A new sequence type (ST1445) was found besides confirming ST239 as the major sequence type (60.53%). A dendrogram generated from our own MLST database showed all the bootstrap values ≤ 50%.
CONCLUSIONOur preliminary epidemiology data show SCCmec III, ST239 and agr type 1 of S. aureus as the predominant strains in LRTIs in Mainland of China.
Alleles ; Anti-Bacterial Agents ; therapeutic use ; China ; epidemiology ; Drug Resistance, Bacterial ; genetics ; Humans ; Microbial Sensitivity Tests ; Prospective Studies ; Respiratory Tract Infections ; epidemiology ; Staphylococcal Infections ; epidemiology ; Staphylococcus aureus ; drug effects ; pathogenicity
10.Drug-resistant genes carried by Acinetobacter baumanii isolated from patients with lower respiratory tract infection.
Ning DAI ; De-zhi LI ; Ji-chao CHEN ; Yu-sheng CHEN ; Rong GENG ; Ying-hui HU ; Jing-ping YANG ; Juan DU ; Cheng-ping HU ; Wei ZHANG ; Jia-shu LI ; Qin YU ; Huan-ying WAN ; Lan MU ; Xiao-ning ZHONG ; Li-ping WEI ; Jian-jun MA ; Qiu-yue WANG ; Ke HU ; Gui-zhen TIAN ; Shao-xi CAI ; Rui-qin WANG ; Bei HE ; Si-qin WANG ; Zhan-wei WANG ; Su-rui ZHAO ; Zhan-cheng GAO
Chinese Medical Journal 2010;123(18):2571-2575
BACKGROUNDAcinetobacter baumanii (A. baumanii ) remains an important microbial pathogen resulting in nosocomial acquired infections with significant morbidity and mortality. The mechanism by which nosocomial bacteria, like A. baumanii, attain multidrug resistance to antibiotics is of considerable interest. The aim in this study was to investigate the spread status of antibiotic resistance genes, such as multiple β-lactamase genes and aminoglycoside-modifying enzyme genes, from A. baumanii strains isolated from patients with lower respiratory tract infections (LRTIs).
METHODSTwo thousand six hundred and ninety-eight sputum or the bronchoalveolar lavage samples from inpatients with LRTIs were collected in 21 hospitals in the mainland of China from November 2007 to February 2009. All samples were routinely inoculated. The isolated bacterial strains and their susceptibility were analyzed via VITEK-2 expert system. Several kinds of antibiotic resistant genes were further differentiated via polymerase chain reaction and sequencing methods.
RESULTSTotally, 39 A. baumanii strains were isolated from 2698 sputum or bronchoalveolar lavage samples. There was not only a high resistant rate of the isolated A. baumanii strains to ampicillin and first- and second-generation cephalosporins (94.87%, 100% and 97.44%, respectively), but also to the third-generation cephalosporins (ceftriaxone at 92.31%, ceftazidine at 51.28%) and imipenem (43.59%) as well. The lowest antibiotic resistance rate of 20.51% was found to amikacin. The OXA-23 gene was identified in 17 strains of A. baumanii, and the AmpC gene in 23 strains. The TEM-1 gene was carried in 15 strains. PER-1 and SHV-2 genes were detected in two different strains. Aminoglycoside-modifying enzyme gene aac-3-Ia was found in 23 strains, and the aac-6'-Ib gene in 19 strains. aac-3-Ia and aac-6'-Ib genes hibernated in three A. baumanii strains that showed no drug-resistant phenotype.
CONCLUSIONSA. baumanii can carry multiple drug-resistant genes at the same time and result in multi-drug resistance. Aminoglycoside-modifying enzyme genes could be hibernating in aminoglycoside sensitive strains without expressing their phenotype.
Acinetobacter ; genetics ; metabolism ; pathogenicity ; Acinetobacter Infections ; microbiology ; Bacterial Proteins ; genetics ; Bronchoalveolar Lavage Fluid ; microbiology ; Drug Resistance, Multiple, Bacterial ; genetics ; Humans ; Microbial Sensitivity Tests ; Polymerase Chain Reaction ; Respiratory Tract Infections ; microbiology ; Sputum ; microbiology