Epidemiological investigation on an epidemic of methicillin-resistant Staphylococcus aureus infection / 中国感染控制杂志

Objective To investigate transmission routes of healthcare-associated infection(HAI)caused by methi-cillin-resistant Staphylococcus aureus (MRSA),and make effective measures for preventing and controlling the oc-currence and epidemic of HAI caused by multidrug-resistance bacteria.Methods From February 24 to March 29, 2012,12 MRSA-infected patients were performed epidemiological study,these patients underwent bronchoscopy be-cause of tracheal stenosis,strains were identified by amplifying the sequences of 16S rRNA ,femA and mecA with real-time quantitative polymerase chain reaction (PCR),homology analysis of strains were performed by Spa geno-typing.Results All 12 MRSA-infected patients were susceptible to multidrug-resistance bacterial infection,5 cases of MRSA infection occurred during this hospitalization.Detection of specimens from health care workers and envi-ronment were all negative;Spa gene of all 12 MRSA isolates was type t 030 ,which was the main epidemic strain in Asia;Spa gene of Staphylococcus aureus isolated from nurses’noses was type t1425 .Conclusion The assumption of MRSA spread among health care workers aren’t supported by the epidemiological investigation results,genotypes of 12 MRSA isolates are identical,but the result of gene typing can’t be as the evidence of homology of infection ;patients at high risk for MRSA infection should be screened as early as possible,early contact isolation should be performed,so as to prevent and control the occurrence of HAI.

Infection progress of arbuscular mycorrhizae on tissue-cultured plantlets of Pinellia ternata / 中国中药杂志

<p><b>OBJECTIVE</b>To study the Arbuscular mycorrhizal (AM) formation progress and infection characteristics between tissue culture plantlets of Pinellia ternata and Glomus mosseae.</p><p><b>METHOD</b>The tissue culture plantlets of P. ternata were inoculated with G. mosseae, the formation of AM were sampled and observed with microscopy by staining.</p><p><b>RESULT AND CONCLUSION</b>The hyphae of G. mosseae began to penetrate the root epidermis after 10 days of inoculation. Lots of intracellular hyphae formed in cortex cells at the 15th day. Arbuscules started to form and there were some hyphae on the root at the 20th day. At the 25th day, many arbuscules formed and most as Arum type. Some arbuscles started to disintegrate at the 30th day, and a few of vesicles occurred. Lots of spores formed after 35 days. At the 40th day, some vesicles began to decline. The hand section showed that the intercellular hyphae gradually formed in intercellular space, and the hyphae branched in cortex cells and occupied most cell lumen finally. It is expounded that P. ternata and G. mosseae could recognize each other quickly and form a symbiont system.</p>

Effects of seed priming on salt tolerance in Prunella vulgaris seed germination under saline conditions / 中国中药杂志

<p><b>OBJECTIVE</b>Selecting an effective way to increase salt-resistance of Prunella vulgaris seed through seed priming technology.</p><p><b>METHOD</b>The treatment of salt stress to P. vulgaris seeds was made by the different concentrations of NaCl solutions. Primed seeds germinated under 0.8% NaCl.</p><p><b>RESULT</b>As concentrations of NaCl increasing, seed germination percentage, germination index and vitality index reduced. Primed with 15%-35% PEG, 100-500 mg x L(-1) GA3 and 0.4%-2.0% KNO3-KH2PO4 could enhance seeds germination index and vitality index under salt stress while treated with NaCl seeds germination percentage reduced.</p><p><b>CONCLUSION</b>Treated with PEG, GA3, KNO3-KH2PO4 under proper concentration, the seed vigor, seed resistance under salt stress increased.</p>

Effects of seed priming on drought tolerence in Prunella vulgaris / 中国中药杂志

<p><b>OBJECTIVE</b>To explore an effective way to increase drought tolerance of Prunella vulgaris seed.</p><p><b>METHOD</b>The treatment of drought stress to P. vulgaris seeds was made by the different concentrations of PEG solutions. Primed seeds germinated under 25% PEG.</p><p><b>RESULT</b>As concentrations of PEG increasing, seed germination percentage, germination index and vitality index reduced. Primed with 20%-25% PEG, 300-500 mg x L(-1) GA3 and 1.6%-2.0% KNO3-KH2PO4 could enhance three population seeds germination index and vitality index under drought stress. Treated with NaCl, seeds germination percentage and germination index of two population increased, which came from Nanjing Zijinshan and Anhui Jinzhai, respectively, while those of seeds from Gansu Chengxian reduced.</p><p><b>CONCLUSION</b>Treated with PEG, GA3, KNO3-KH2 PO4 under proper concentration, seed vigor, seed resistance under drought stress would increase.</p>