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Objective:To analyze the molecular and virulence characteristics of Staphylococcus aureus ( S. aureus) isolated from neonates. Methods:A total of 189 S. aureus isolates were collected from Beijing Children′s Hospital from January 2013 to October 2019 and analyzed by multilocus sequence typing (MLST), staphylococcal cassette chromosome mec (SCC mec) typing and Spa typing. Panton-valentine leucocidin (PVL)-encoding gene ( pvl) and 21 superantigen virulence genes were also detected. Results:The 189 S. aureus strains were isolated from respiratory secretions ( n=125), pus ( n=55), blood ( n=8) and pleural effusion ( n=1). There were 98 methicillin-susceptible S. aureus (MSSA) belonging to 42 MSSA clones and 91 methicillin-resistant S. aureus (MRSA) belonging to 26 MRSA clones. ST188-t189 and ST59-SCC mecⅣa-t437 were the predominant MSSA and MRSA clones accounting for 11% and 53%, respectively. The prevalence of pvl gene in MRSA isolates was significantly higher than that in MSSA isolates (32% vs 10%, P<0.01). There were 166 isolates (88%) carrying at least one superantigen virulence gene and among the 21 genes, seq and seb were the most common genes accounting for 47% and 43%, respectively. The most common superantigen genotype was seb- sek- seq. The positive rates of superantigen genes in MRSA and MSSA isolates were 85% (77/91) and 90% (88/98), respectively ( P>0.05). Conclusions:The main clones of MRSA and MSSA were different in neonates. ST59-SCC mecⅣa-t437 was the most predominant MRSA clone, while ST188-t189 was the most predominant MSSA clone. MSSA clones were more dispersed. The prevalence of pvl gene in MRSA was higher than that in MSSA. No significant difference in the prevalence of superantigen genes was observed between MRSA and MSSA.
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Drug-induced liver injury (DILI) is one of the main causes of acute liver failure, black box warnings, and drug withdrawal from the market, and it is also a major concern in public health, drug research and development, and the pharmaceutical industry. However, a lack of specific diagnostic markers for DILI makes the diagnosis of this disease a major challenge for clinicians. This article summarizes the recent advances in DILI research, including potential mechanisms, pathological features, biomarkers, and in vitro methods, in order to provide a reference for clinical and pathological diagnosis and prognostic evaluation of DILI.
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Objective To investigate the clinical features and prognosis related risk factors in nonalcoholic steatosis liver cirrhosis(NASLC).Methods From January 1st,2006 to December 31st, 2013,in a prospective cohort of 12 489 patients with liver cirrhosis set,174 patients were with NASLC and 306 patients with hepatitis B were the control.The patients were followed up every three months. The clinical data of patients were collected,including gender,age,height,body weight,blood pressure, history of hypertension,history of diabetes,family history of tumor,blood glucose level,high density lipoprotein cholesterol(HDL-C)level,low density lipoprotein cholesterol(LDL-C)level,triglyceride level,white blood cell,platelet,prothrombin time activity,total bilirubin,albumin,cholinesterase,blood urea nitrogen,creatinine,alpha-fetoprotein,abdominal ultrasound,abdominal computer tomography and endoscopy.Body mass index(BMI)and Child-Pugh scores were calculated.The differences between the two groups were analyzed in the incidence of ascites,hepatic encephalopathy,hepatorenal syndrome, esophageal varices bleeding,liver failure,hepatocellular carcinoma and mortality.Chi square test and t test were performed for statistical analysis.logistic regression analysis was used to analyze the risk factors associated with hepatocellular carcinoma in patients with NASLC.Results The proportion of female in NASLC group was higher than that in posthepatic cirrhosis group(56.0%,47/84 vs 28.7%,49/171), and the difference was statistically significant(χ2 =17.653,P<0.01).BMI,systolic pressure,diastolic pressure,level of fasting blood glucose,LDL-C,triglyceride,prothrombin time activity,albumin, cholinesterase,cases number of hypertension,diabetes and metabolic syndrome of NASLC group were all significantly higher than those of posthepatic cirrhosis group(t=6.267,4.091,5.773,2.914,1.877, 2.044,2.326,1.935 and 2.023;χ2=7.241,9.399 and 81.367;all P<0.05),however,serum levels of HDL-C,total bilirubin and creatinine were significantly lower than those of posthepatic cirrhosis group (t=6.127,8.487 and 3.261;all P < 0.05).T he three-year accumulative incidences of hepatic encephalopathy,hepatorenal syndrome and liver failure of NASLC group(8.3%,7/84;1.2%,1/84;0) were all lower than those of posthepatic cirrhosis control group(22.2%,38/171;9.9%,17/171 and 5.8%, 10/171;χ2 = 5.751,3.862 and 3.927,all P< 0.05).The three-year accumulative incidence of hepatocellular carcinoma of NASLC was 8.3%(7/84).The three-year accumulative incidence of mortality was lower than that of posthepatic cirrhosis group(2.4%,2/84 vs 13.5%,23/171;χ2 = 3.884,P=0.049).The results of logistic regression analysis showed that BMI(odds ratio(OR)= 1.469,95%confidence interval(CI)1.093 to 2.176,P=0.016)and diabetes(OR=1.734,95% CI 1.269 to 2.388, P=0.012)were independent risk factors associated with hepatocellular carcinoma in NASLC patients. Conclusions NASLC occurrs mainly in female with good liver function.BMI and diabetes are the risk factors associated with hepatocellular carcinoma in patients with NASLC.
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Objective To investigate the clinical features,diagnosis and treatment of neck masses in newborns. Methods All cases of neck masses in newborns admitted to NICU of Beijing Children's Hospital form January 2016 to Febrary 2018 were included,and the clinical manifestations,examinations,treatments and outcomes were evaluated. Results Fourteen cases of newborn's neck masses were collected. The time of onset was 8 cases at birth,1 case earlier than 7 days,5 cases after 7 days. Seven cases were admitted with dyspnea,10 cases combined with neck infections. Neck ultrasound examinations were performed in all 14 cases,CT scan in 2 cases,MRI in 10 cases. Five cases were given endotracheal intubation after admission, among them 3 cases needed mechanical ventilation. Nasal continuous positive airway pressure was used in 3 cases. Thirteen cases received anti-infective treatment. Punctures were performed in 4 cases. Surgical resec-tions were taken in 6 cases. Two cases were diagnosed as local primary infection. Six cases were confirmed by surgery,including 4 cases of branchial cleft cyst,1 case of esophageal duplication and 1 case of lymphangio-ma. Conclusion The neck masses of the newborn is prone to upper airway obstruction. Part of them need endotracheal intubation to open the airway. And the infection can be combined. There is a certain rate of misdiagnosis before operation,and the treatment plan is different according to the nature of the mass.
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Objective To analyze the clinical and molecular features of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infection in neonates and to investigate their antibiotic resistance profiles.Methods A total of 35 invasive CA-MRSA strains were collected from six hospitals in 2014.Multilocus sequence typing (MLST), staphylococcal cassette chromosome mec (SCCmec) typing and spa typing were used to analyze these isolated CA-MRSA strains.In vitro antibiotic susceptibilities of those strains to 15 antibiotics were analyzed by using agar dilution method.Results Up to 88.6% patients were late-onset infection and septicemia (24, 68.5%) was the most common infection among the 35 cases.A total of 16 patients (45.7%) suffered from complications.Caesarean section and premature birth were risk factors for invasive CA-MRSA infection.ST59-MRSA-SCCmecⅣa-t437 (14, 40%) was the most predominant CA-MRSA clone, followed by ST59-MRSA-SCCmecⅤ-t437 (13, 37.1%).The incidence of severe complications caused by ST59-MRSA-SCCmecⅤ-t437 was higher than that caused by ST59-MRSA-SCCmecⅣa-t437 (P<0.05).Up to 85.7% of the isolated CA-MRSA strains were multidrug-resistant strains.Conclusion This study shows that neonatal invasive CA-MRSA infections mainly result in septicemia and are often accompanied by complications and involve multiple organs.Multidrug-resistant CA-MRSA strains are prevalent in neonates.ST59-MRSA-SCCmecⅣa-t437 is the predominant clone causing neonatal invasive CA-MRSA infection.
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Objective To explore the mechanism of high mobility group protein 1 (HMGB1) involved in endoplasmic reticulum stress (ERS) induced by brain ischemia/reperfusion (I/R),based on I/R-HMGB1-ERS as the breakthrough point.Methods The brain of rats birthed 1-3 days was harvested,and the brain cells were cultured in vitro,which were used in the experiment when the cells were in the third passage.The cells were divided into two groups:cells in blank control group were cultured under the normal conditions without any treatment,and the cells in hypoxia/reoxygenation group were cultured with 99.9％ nitrogen for 60 minutes (hypoxia) followed by opening the bottle neck for reoxygenation 120 minutes to simulate I/R model.The HMGB1 gene was silenced by using small interfering RNA (siRNA,siRNA and transfection reagent Lipofectamine 2000 mixture gradient was transfected into the cultured cells) as HMGB1-siRNA transfection group,and blank control (without any treatment) and negative control group (transfected with control siRNA) served as controls.The mRNA and protein expressions of HMGB1 and ERS related molecules were determined by real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western Blot.Results ① In cells of hypoxia/reoxygenation group,the mRNA and protein expressions of HMGB1 and ESR related proteins,including glucose regulating protein 78 (GRP78),C/EBP homologous protein (CHOP) and caspase-12,were significantly higher than those of blank control group with statistical difference (the value in blank control group was served as baseline 1,HMGB1 mRNA:3.19±0.48 vs.1,t =2.183,P =0.008;GRP78 mRNA:2.07±0.33 vs.1,t =3.292,P =0.016;CHOP mRNA:1.93±0.28 vs.1,t =2.573,P =0.021;caspase-12 mRNA:2.42±0.42 vs.1,t =2.261,P =0.027:HMGB1 protein:2.28±0.36 vs.1,t =2.042,P =0.009;GRP78 protein:1.33±0.24 vs.1,t =2.781,P =0.016;CHOP protein:1.67±0.34 vs.1,t =2.174,P =0.021;easpase-12 protein:1.36±0.44 vs.1,t =3.192,P =0.008).It was indicated that ERS related molecules involved in cell hypoxia/reoxygenation process.2② After HMGB1 gene was silenced by siRNA,the cells after hypoxia/reoxygenation showed a decrease in the mRNA and protein expressions of HMGB1 and ERS related moleculars as compared with those of blank control group and negative control group (served the value in blank control group as baseline 1,HMGB1 mRNA:0.27±0.12 vs.1,1.02 ± 0.04;GRP78 mRNA:0.16 ± 0.13 vs.1,0.96 ± 0.04;CHOP mRNA:0.47 ± 0.09 vs.1,0.98 ± 0.07;caspase-12 mRNA:0.31 ±0.11 vs.1,1.05±0.02;HMGBI protein:0.23±0.04 vs.1,1.08±0.01;GRP78 protein:0.14±0.09 vs.1,1.35±0.03;CHOP protein:0.32±0.10 vs.1,0.93±0.06;caspase-12 protein:0.27±0.09 vs.1,0.97±0.08;P ＜ 0.05 or P ＜ 0.01).It was indicated that HMGB1 involved in ERS related with GPR7,CHOP,caspase-12.Conclusion Hypoxia/reoxygenation brain intracellular HMGB1 and ERS related molecules expression levels were significantly up-regulated,and silencing HMGB1 gene can significantly inhibit the expression levels of these molecules,and I/R-HMGB 1-ERS pathway may participate in the mechanism of brain I/R injury.
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AIM: To investigate the effects of EPA and DHA on oxidative stress of lipopolysaccharide-stimulated rat mesangial cells. METHODS: The glomerular mesangial cells (GMCs) were stimulated by lipopolysaccharide (LPS) and incubated with EPA (10 μmol/L or 100 μmol/L) and DHA (10 μmol/L or 100 μmol/L) for 24 h, 48 h and 72 h. The activity of SOD, GSH-Px and the level of MDA was measured. The protein and mRNA expressions of MCP-1 and TGF-β_1 were detected by immunocytochemistry and real-time PCR method, respectively. RESULTS: The activities of SOD and GSH-Px were decreased and the concentration of MDA was increased when stimulated with LPS. EPA and DHA increased the activities of SOD and GSH-Px and decreased the concentration of MDA significantly. Meanwhile, the protein and mRNA expressions of MCP-1 and TGF-β_1 stimulated by LPS were decreased. DHA was more effective than EPA at the same concentration. CONCLUSION: EPA and DHA enhance the activities of antioxidant enzymes, decrease the concentration of MDA and inhibit the expression of TGF-β_1 and MCP-1, suggesting that the protective effect of EPA and DHA on kidney is related to the antioxidation and the inhibition of TGF-β_1 and MCP-1 expression.