Genotyping and drug resistance of methicillin-resistant Staphylococcus aureus / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the genotype of staphylococcal chromosomal cassette mec (SCCmec) in methicillin-resistant Staphylococcus aureus (MRSA) isolated from burn wards and its current status of drug resistance.</p><p><b>METHODS</b>One hundred and seventy-nine strains of Staphylococcus aureus were isolated from wound excretion, blood, and sputum samples of patients that were admitted to ICU or public wards of our Department of Burns and Plastic Surgery from September 2012 to September 2013. Among them, 68 strains were from ICU and 111 strains from public wards. The MRSA phenotype of Staphylococcus aureus was detected with cefoxitin K-B disk diffusion method, and the isolation rates of MRSA in ICU and public wards were compared. Genotyping of SCCmec was performed by PCR in strains of MRSA. In the meantime, the identification result of MRSA by K-B method was verified through detecting methicillin-resistant determinant mecA. The antimicrobial resistance of MRSA and methicillin-sensitive Staphylococcus aureus (MSSA) to 23 kinds of commonly used antibiotics in clinic were detected by K-B disk diffusion method. Except for the antibiotics to which the resistant rates of MRSA were 100.0% or 0, the resistant rates of SCCmecIII MRSA and non-SCCmec III MRSA to the rest of antibiotics were compared. Data were processed with Pearson chi-square test or corrected chi-square test.</p><p><b>RESULTS</b>One hundred and forty-eight strains out of the 179 Staphylococcus aureus were identified as MRSA (accounting for 82.7%), among which 62 were originated from ICU and 86 from public wards. The rest 31 strains of Staphylococcus aureus were MSSA, accounting for 17.3%. The percentage of MRSA in the isolated Staphylococcus aureus was 91.2% (62/68) in ICU, which was significantly higher than that in the public wards [77.5% (86/111), χ2 = 5.526, P = 0.019]. PCR detection showed that the 148 strains of MRSA harbored the mecA gene, out of which 106 strains were SCCmec III positive, accounting for 71.6%. The percentages of SCCmec III type MRSA in MRSA isolated from ICU and public wards were respectively 72.6% (45/62) and 70.9% (61/86), showing no statistically significant difference (χ2 = 0.048, P = 0.826). The 148 strains of MRSA were 100.0% resistant to a total of 8 kinds of antibiotics including penicillin and cephalosporins, but it was 0 for vancomycin, teicoplanin, linezolid, tigecycline, nitrofurantoin, and quinupristin/dalfopristin. Except for the 6 kinds of antibiotics to which the resistant rates of MRSA and MSSA were 0, resistant rates of MRSA to the remaining 17 kinds of antibiotics were significantly higher than those of MSSA (with χ2 values from 4.091 to 138.546, P < 0.05 or P < 0.01). Resistant rates of the 106 strains of SCCmecIII type MRSA to levofloxacin, ciprofloxacin, rifampicin, tetracycline, erythrocin, lincomycin, gentamicin, clindamycin were respectively 56.6% (60/106), 85.8% (91/106), 89.6% (95/106), 86.8% (92/106), 84.9% (90/106), 78.3% (83/106), 92.5% (98/106), 74.5% (79/106), and they were significantly higher than those of the 42 strains of non-SCCmec III type MRSA [33.3% (14/42), 61.9% (26/42), 71.4% (30/42), 66.7% (28/42), 69.0% (29/42), 57.1% (24/42), 71.4% (30/42), 52.4% (22/42), with χ2 values from 4.801 to 11.377, P < 0.05 or P < 0.01].</p><p><b>CONCLUSIONS</b>Isolation rate of MRSA from burn wards in our hospital is high, and drug resistance status of this strain against antibiotics is very serious. SCCmec III is the major genotype of the isolated MRSA, but no strains resistant to the glycopeptide antibiotics are found.</p>

Overexpression of extracelluar signal regulated protein kinase in the temporal lobe of human drug-resistant epilepsy / 中华神经科杂志

Objective To investigate expression of extracelluar signal regulated protein kinase(ERK)and phosphorylation ERK(p-ERK)in the temporal lobe from patients with DR-TLE so as to explore the possible roles of ERK in the pathogenesis of DR-TLE.Methods Expression of ERK was detected with Western blot and immunohistochemistry in 32 patients with DR-TLE(24 temporal lobe,8 hippocampi),as compared with 12 controls(9 temporal lobe,3 hippocampi).Results ERK and p-ERK expression in DR-TLE was significantly higher(0.2266?0.0613,0.2097?0.0183 and 0.1924?0.0054,respectively)than those of controls(0.1840?0.0023,0.1974?0.0056 and 0.1825?0.0063,respectively,all P

The expression of heat shock 27 000 associated protein 1 in the brains of drug-refractory epilepsy / 中华神经科杂志

Objective To study the expression of heat shock 27 000 associated protein 1 ( HSPBAP1, GenBank: AK096705) in the brain tissues of patients with drug-refractory epilepsy and discuss its function in the pathogenesis. Methods Fluorescent quantitative polymerase chain reaction ( FQ-PCR) and immunohistochemistry were used to test the expression of HSPBAP1 in the surgically removed brain tissues of patients with drug-refractory epilepsy from the brain bank of our department ( n = 36) , and the results were compared with that of normal controls (n = 8 ). Results The relative expression of HSPBAP1 mRNA in the brains of patients with drug-refractory epilepsy was more than 34. 11 times that of controls, and HSPBAP1 protein expression was significantly increased in temporal lobe cortex (0. 0507?0. 0003, P

The overexpression of ULBP2 in the brain of drug-refractory epilepsy / 中国免疫学杂志

Objective:To study the expression of ULBP2 protein in the brain tissues of patients with drug-refractory epilepsy and its clinical significance.Methods:Gene-chip,immunofluorescence and Western blot were used to test expression of ULBP2 in the surgically removed brain tissue of patients with drug-refractory epilepsy from the brain bank of our department(n=42),and the results were compared with that of normal controls (n=12).Results:The relative increasing expression of ULBP2-gene in the brain of patients with drug-refractory epilepsy,and ULBP2 protein expression was significantly increased in temporal lobe cortex of patients with drug-refractory epilepsy as compared with the same regions of the controls specimens.Conclusion:The results indicate that the overexpression of ULBP2 may be involved in the pathophysiology of drug-refractory epilepsy.

Genetic Toxicity of Magnesium Sulfate to Root Tip Cells of Vicia faba / 环境与健康杂志

Objective To study the genetic toxicity of magnesium sulfate to the root tip cells of Vicia faba. Methods The root tip cells of Vicia faba with 1.5-2 cm root tip were taken as the subjects and were exposed to magnesium sulfate of different concentrations(0.50%-2.00%) for 6 h. In the other test,the cells were treated with 1.5% magnesium sulfate for 2,4,6,8 and 10 hours respectively. The distilled water and potassium dichromate (0.05%) were used as the negative and positive control respectively. The micronucleus and the chromosomal aberration were calculated after 24 hours of culture. Results Compared with the negative control group,0.1%,0.15%,0.175% and 0.2% of magnesium sulfate increased the micronucleus and 0.05%,0.1%,0.15%,0.175%,0.2% of magnesium sulfate increased the chromosomal aberration in Vicia faba root tip cells. Compared with the control group (0 h),both of the micronucleus and the chromosomal aberration of Vicia faba root tip cells increased (P