The inhibition effect on methicillin resistant staphylococcus aureus N31 5 of human βdefensin 3 combined with antibiotics / 预防医学

Objective To analyze the inhibition effect of antimicrobial peptide human βdefensin 3 (hBD3 )against methicillin resistant Staphylococcus aureus (MRSA)N31 5.Methods Antimicrobial peptide hBD3 was synthesized.The direct inhibition on N31 5 was detected by the MIC (minimal inhibitory concentration,MIC)test,antibacterial activity test and the analysis on some important functional genes.The peptide was combined with penicillin,tetracycline,cephradine, rifampin,vancomycin,cefuroxime and chloramphenicol to evaluate the effects on antibiotic MIC values.Results The MIC of hBD3 against N31 5 was 8 μg/mL and the bactericidal activity was observed while the hBD3 concentration reached 2 μg/mL.The peptide hBD3 could improve the expression of agr and reduce the expression of icaA.With 5 μg/mL peptide hBD3,the MIC values against N31 5 of penicillin,cephradine,vancomycin,cefuroxime and chloramphenicol were dropped down.Conclusion There is considerable bactericidal activity of antimicrobial peptide hBD3 against MRSA N31 5. Antibiotic peptide hBD3 could be used to prevent the spread of antibiotic resistant bacteria in the future.

Determination of ascitic bacterial 16S rRNA by quantitative PCR-microarray in the diagnosis of spontaneous bacterial peritonitis / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To evaluate the significance of determining ascitic bacterial 16S rRNA by quantitative PCR combined with microarray (PCR-microarray) in the diagnosis of spontaneous bacterial peritonitis (SBP).</p><p><b>METHODS</b>Ascitic bacterial 16SrRNA was determined by real time fluorescent quantitative PCR-microarray in 76 cases of suspected SBP and 6 cases of non-infectious ascites with chronic liver diseases. The results were compared with ascitic bacterial culture simultaneously.</p><p><b>RESULTS</b>Of 76 ascitic samples, 17 were detected bacteria positive by PCR-microarray, including 8 Grams positive(G+) and 9 Grams negative(G-), which was higher than that by bacterial culture which had only 6 ascitic samples detected positive (all G-); the positive rates were 22.4% vs 7.9%, respectively (P < 0.01). The bacterial strains detected by both methods in 6 cases had a consistency with each other. No bacteria were detected in another 6 cases of non-infectious ascites with chronic liver diseases.</p><p><b>CONCLUSIONS</b>Determination of ascitic bacteria 16S rRNA by PCR-microarray has a higher specificity and sensitivity in the diagnosis of SBP as compared with the bacteria culture. Application of this novel method can not only accelerate SBP diagnosis but also stratify the different pathogens.</p>

The effects of hippophae juice on free radical metabolism of rat skeletal muscle and the content of Hb, Ck, T in blood / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To explore the effects of hippophae juice on free radical metabolism of rat skeletal muscle and partial biomarkers in blood.</p><p><b>METHODS</b>Randomly dividing the 30 SD rats into 3 groups (n = 10): sedentary group, training group and hippophae training group. Measuring related indices of skeletal muscle and blood in rat after 6 week training and hippophae juice supplement.</p><p><b>RESULTS</b>Compared with training group, hippophae training group showed obviously longer exhaustive time, significantly increased antioxidant enzyme in skeletal muscle, remarkably decreased malonaldehyde (MDA) content in skeletal muscle, obviously increased testosterone (T) and hemoglobin (Hb) content in blood, significantly decreased creatine kinase (CK).</p><p><b>CONCLUSION</b>Hippophae juice can impove the antioxidant ability of rat skeletal muscle, the level of T and Hb in blood, delay fatigue, therefore effectively enhance the aerobic stamina of rat.</p>

Determination of ascitic bacterial 16S rRNA gene in the rapid diagnosis of spontaneous bacterial peritonitis / 中国医学科学院学报

<p><b>OBJECTIVE</b>To evaluate the value of ascitic bacterial 16S rRNA gene determination in the rapid diagnosis of spontaneous bacterial peritonitis (SBP).</p><p><b>METHODS</b>16S rRNA gene from bacterial DNA in ascites was determined by quantitative fluorescent polymerase chain reaction (PCR) in 76 patients with suspected SBP and 6 patients with non-infectious ascites. The results were compared with those obtained from bacterial culture.</p><p><b>RESULTS</b>The positive rate of SBP was 22.4% among patients detected with ascitic bacterial 16S rRNA gene determination-based quantitative fluorescent PCR, which was significantly higher than that (7.9%) in patients only received bacterial culture (P<0.05). In addition,in 6 patients with non-infectious ascites,both the 16S rRNA gene determination-based quantitative fluorescent PCR and bacterial culture showed negative results.</p><p><b>CONCLUSIONS</b>16S rRNA gene determination-based quantitative fluorescent PCR can be an effective tool for the rapid diagnosis of SBP. It is more sensitive than the bacterial culture.</p>

The roles of saliva testing for preventing hepatitis B virus spreading / 中华预防医学杂志

<p><b>OBJECTIVE</b>To discuss the significance of testing hepatitis B virus (HBV) from saliva in HBV patients.</p><p><b>METHODS</b>HBV DNA content in serum and saliva of 200 HBV patients and 20 healthy subjects were detected by fluorescence quantitative polymerase chain reaction. According to the serum level of HBV content, four groups were divided: control group A, group B negative, low virus C (1 x 10(3) - 1 x 10(5) copies/ml) and high-group D ( > 1 x 10(5) copies/ml). The relationship of serum and virus content in saliva was analysed.</p><p><b>RESULTS</b>Of 200 HBV cases, 180 were found HBV DNA in serum with positive rate of 90.0%; while 145 were found HBV DNA in saliva with positive rate of 72.5%, and there was no significant difference (chi2 = 1.35, P > 0.05). The significant difference was observed in testing serum and saliva in Group C (100.0% vs. 38.5%; Z = 14.11, P < 0.01). In group D, there was no significant difference found either (100.0% vs. 83.8%; chi2 = 1.05, P > 0.05). Group D virus serum had a high average level of (6.63 +/- 1.55) log copies/ml virus and in the saliva had an average level of (5.21 +/- 1.85) log copies/ml; saliva had serum viral load lower than an order of magnitude average. No HBV DNA was found in serum or saliva from 20 health subjects.</p><p><b>CONCLUSION</b>When the serum contains a high content of HBV DNA virus, the content of saliva HBV DNA virus should be likely high, which might pose a threat of source of infection. A precise quantitative detection of HBV DNA in saliva might be used as evaluation of the level of virus in the body copy for judgment of infection.</p>

Clinical significance of intrahepatic hepatitis B core antigen (+) in patients with chronic hepatitis B / 中华肝脏病杂志

<p><b>OBJECTIVE</b>This study aimed to assess the clinical significance of intrahepatic hepatitis B core antigen (HBcAg) (+) in patients with chronic hepatitis B (CHB).</p><p><b>METHODS</b>200 CHB patients were prospectively studied using fluorescence quantitative PCR (FQ-PCR), combined PCR with fluorescence probe hybridization technique, to determine serum HBV DNA. Serum HBeAg was measured quantitatively. Liver biopsies were performed and immunohistochemistry stained liver slides were examined in all the cases. Correlation analyses were performed.</p><p><b>RESULTS</b>Based on the HBV DNA levels, the patients were divided into 5 groups: group A (<3 log10 copies/ml) n=20, group B (>or=3 log10 copies/ml-<5 log10 copies/ml) n=13, group C (>or=5 log10 copies/ml-<6 log10 copies/ml) n=24, group D (>or=6 log10 copies/ml-<8 log10 copies/ml) n=116, and group E (>or=8 log10 copies/ml) n=27, and 87.5% of the CHB patients were intrahepatic HBcAg (+). The rate of HBcAg (+) was 55.0% (11/20) in group A, 53.8% (7/13) in group B, 75.0% (19/24) in group C, 96.6% (112/116) in group D, and 100% (27/27) in group E. A strong correlation was found between the rate of HBcAg (+) and the level of serum HBV DNA (r=0.80). This type of association also appeared between serum HBV DNA levels and HBeAg (+) (r=0.47). Of 20 CHB patients who were serum HBV DNA negative, 25% (5) were HBeAg (+), and 55% (11) were HBcAg (+), whereas 15 patients were both HBV DNA (-) and HBeAg (-), and 46.7% (7) were HBcAg (+).</p><p><b>CONCLUSIONS</b>Intrahepatic HBcAg (+) in CHB patients might be more reliable in reflecting HBV replication. Determination of HBcAg (+) may have clinical significance for evaluating the efficacy of antiviral therapy and for predicting the therapeutic responses to different antiviral agents.</p>