Immunological mechanisms of Neisseria gonorrhoeae infection: An update / 中华男科学杂志

Neisseria gonorrhoeae (NG), as a pathogen of gonorrhea, is strictly limited to growth on the human host. In case of gonococcal infection, the body may recruit such inflammatory cells as neutrophils to resist the invasion of NG or initiate its adaptive immune response by antigen presentation to eliminate the pathogen. However, a series of immune escape mechanisms of NG make it difficult to clear up the infection. In the innate immune system, NG can not only secrete thermonuclease to degrade neutrophile granulocytes, inhibit respiratory burst to resist killing by neutrophils, activate NLRP3 to prompt the pyronecrosis of inflammatory cells, but also regulate the differentiation of macrophages to reduce the inflammatory response, combine with factor H to evade complement-mediated killing. NG infection can hardly give rise to effective adaptive immune response and immune memory, but can promote TGF-β production to inhibit Th1/Th2-mediated adaptive immune response, bind to CEACAM1 on the B cell surface to promote apoptosis in B cells, and combine with CEACAM1 on the T cell surface to inhibit helper T cell proliferation, which makes it difficult for B cells to produce high-affinity specific antibodies. With the increasing drug-resistance of NG, immunological studies may play a significant role in the development of novel therapies and effective vaccines against the infection.

Determination of entrapment efficiency of coumarin 6-loaded PLGA nanoparticles by high-speed centrifugation / 中国药学杂志

OBJECTIVE: To establish a method for determination of the entrapment efficiency of coumarin 6-loaded PLGA nanoparticles by high-speed centrifugation. METHODS: The nanoparticle suspensions were diluted by different vehicles, and free drugs were then separated by high-speed centrifugation. The separation effect for free drug and nanoparticles as well as the effect of diluting solvent on nanoparticles morphology were observed by scanning electron microscopy. The method was validated and the determination condition was optimized. RESULTS: The calibration curve for coumarin 6 had good linearity in the range of 0.8-100 ng(r=1.000 0), and the precision were high with RSD≤1.28%. After diluting the nanoparticle suspensions with 1% TPGs, high-speed centrifugation could effectively separate the free drug from nanoparticles. The recovery of free drug was 99.25%-103.00%. The average entrapment efficiencies of coumarin 6-loaded nanoparticles was 88.74% with RSD of 0.65%. CONCLUSION: The method is rapid, accurate and feasible. It can be used to determine the entrapment efficiency of coumarin 6-loaded PLGA nanoparticles.

Influence of sodium citrate concentration in TISAB on detection of water fluoride / 中国地方病学杂志

Objective To observe the influence of sodium citrate concentrations in TISAB on detection of water fluoride,and to explore the feasibility of 0.10 mol/L sodium citrate buffer system in detection of water fluoride.Methods Under pH 5.0 to 5.5,a series of fluoride standards of 0.2,0.5,1.0,2.0 and 5.0 mg/L were measured when sodium citrate concentration was 0.01,0.10,and 1.00 mol/L in the TISAB system.The results of water fluoride measurement were compared,recovery calculated and regression equation of the standard curve was set up.The feasibility of 0.10 mol/L sodium citrate in the TISAB system to detect water fluoride was tested,including interference test,accuracy,confidence limits,as well as precision test.Water fluoride was determined by fluoride ion selective electrode according to the Standard Test Methods for Drinking Water (GB/T 5750.5-2006).Results When the sodium citrate concentrations in the TISAB system were 0.01,0.10 and 1.00 mol/L,and the concentrations of fluoride in the sample were 0.2,0.5,1.0,2.0 and 5.0 mg/L,recoveries of water fluoride were 96.0％,103.0％,179.5％; 80.6％,97.8％,132.2％; 73.3％,97.0％,103.0％; 70.0％,100.0％,87.5％; and 66.4％,102.0％,65.4％.The equation of linear regression was y =lg-1(226.4-E/47.4),y =lg-1(226.4-E/53.4) and y =lg-1(208.1-E/36.9) ; the correlation coefficient(r) were 0.9993,0.9999 and 0.9993.The minimum detectable concentration and limit of quantitation was 0.023 and 0.072 mg/L when sodium citrate was 0.10 mol/L in the TISAB system.Aluminum(Al3+,100 μg),ferrum(Fe3+,800 μg),calcium(Ca2+,1200 μg),Al3+(50 μg) + Fe3+ (800 μg),Al3+(50 μg) + Ca2+(1200 μg) can be masked when sodium citrate was 0.10 mol/L in the TISAB system.The total average recoveries confidence limit R/d was 0.99.The total standard deviation of standard solution,water sample and spiked water sample was less than 5％ of their respective mean concentration.Conclusions High concentration of sodium citrate buffer system has a significant influence on the detection sensitivity and limit of quantification of fluoride ion in water.The capacity of anti-interference of 0.10 mol/L sodium citrate in the TISAB is strong.The confidence limits of precision and accuracy meet the requirements for fluoride determination in a variety of source water and drinking water.

Analysis on variance of common pathogenic bacteria and drug resistance in children in Chengdu area from 2001 to 2006 / 中华儿科杂志

<p><b>OBJECTIVE</b>To investigate the variance and drug resistance of pathogenic bacteria isolated from children with infectious diseases seen between 2001 and 2006 in Chengdu area.</p><p><b>METHODS</b>A total of 2888 pathogenic bacterial strains isolated from children in Chengdu Children's Hospital from 2001 to 2006 were analyzed. Tests were performed according to the guidelines of National Committee for Clinical Laboratory Standards (NCCLS) of the United States.</p><p><b>RESULT</b>(1) Of the 2888 strains, 1845 (63.9%) were Gram negative bacteria. The main pathogenic bacteria included Escherichia coli (Ec, 718 strain, 24.9%), Hemophilus (H, 476 strain, 16.5%), Streptococcus pneumoniae (Sp, 412 strain, 14.3%), Klebsiella pneumoniae (Kp, 369 strain, 12.8%), Staphylococcus aureus (Sa, 353 strain, 12.2%), Staphylococcus epidermidis (Se, 278 strain, 9.6%), Pseudomonas aeruginosa (Pa, 146 strain, 5.1%) and other non-zymocyte (Onz, 136 strain, 4.7%). (2) The common pathogens found in blood specimen were 158 strain, which included Se (78 strain, 49.4%), Ec (23 strain, 14.6%), Kp (17 strain, 10.8%), Sa (14 strain, 8.9%), Onz (14 strain, 8.9%), Sp (7 strain, 4.4%) and Pa (5 strain, 3.2%). (3) The number of common pathogens isolated from patients with lower respiratory tract infection was 2018, including Ec (441 strains, 21.9%), H (430 strains, 21.3%), Sp (368 strains, 18.2%), Kp (253 strains, 12.5%), Sa (207 strains, 10.3%), Se (149 strains, 7.3%), Pa (97 strains, 4.8%) and Onz (73 strains, 3.6%). (4) There were 120 strains of common pathogens isolated from urine specimens, including Ec (78 strains, 65%), Kp (25 strains, 20.8%), Onz (7 strains, 5.8%), Pa (5 strains, 4.2%) and Se (5 strains, 4.2%). (5) There were 497 strains of common pathogens found in pus specimens, including Ec 167 strains, (33.6%), Sa (126 strains, 25.4%), Se (46 strains, 9.3%), H (44 strains, 8.9%), Onz (37 stains, 7.4%), Kp (31 strains, 6.2%), Sp (26 strains, 5.2%) and Pa (20 strain, 4.0%). The trend of drug resistance of pathogenic bacteria to antibiotics deteriorated. The proportion of methicillin-resistant Staphylococcus aureus (MRSA) was 6.7% and the methicillin-resistant coagulase-negative Staphylococci (MRCNS) rate was 20% in 2001 - 2003. The total proportion of extended-spectrum beta-lactamase stains (ESBL(S)) in Ec and Kp was 21.8%, and the rate of beta-lactamase production stains of Hemophilus influenzae (Hi) was 19.4% in 2001 - 2003.The proportion of MRSA was 17.2% and the MRCNS rate was 70.2%, the total proportion of ESBL(S) in Ec and Kp was 43.8%, and the rate of beta-lactamase producing stains of Hi was 39.7% in 2004 - 2006.</p><p><b>CONCLUSION</b>The distribution of common pathogenic bacteria seen in Chengdu Children's Hospital has changed and the trend of drug resistance of pathogenic bacteria to antibiotics deteriorated in recent three years. Regionally monitoring the changes in pathogenic bacteria and the trend of drug resistance to antibiotics is paramount in guiding the pediatric clinical treatment.</p>

Study on liposome preparation technique of Bupleurum chinense volatile oil for injection / 中国中药杂志

<p><b>OBJECTIVE</b>To study the preparation technique of the liposome of Bupleurum chinense volatile oil.</p><p><b>METHOD</b>The composition, entrapment ratio of volatile oil, availability of freeze-drying and the changes of finger prints were studied.</p><p><b>RESULT</b>Entrapment ratio reached 81.9%. After freeze-dried, the remaining ratio of the oil entrapped in the liposome reached 88.6%.</p><p><b>CONCLUSION</b>It is practicable to make B. chinense injection into freeze-dried liposome powder.</p>