Preparation and application of novel polysulfone chiral membranes for the separation of tryptophan enantiomers / 中国药科大学学报

@#To preparate a novel polysulfone chiral membranes, β-cyclodextrin was functionalized with dodecanoyl chloride, and this modified β-cyclodextrin was then incorporated into polysulfone casting solution to form the dodecanoyl-β-cyclodextrin/polysulfone chiral membrane. Meanwhile, current studies have investigated the effect of adding different amount of dodecanoyl-β-cyclodextrin on the pure water flux, bovine serum albumin(BSA)rejection rate and enantioselectivity of the membranes. The morphology of the dodecanoyl-β-cyclodextrin/polysulfone chiral membrane was characterized by scanning electron microscopy(SEM). With the incorporation of dodecanoyl-β-cyclodextrin, the pore structure of the membrane changed significantly, with more finger-like pore structures appearing in the support layer. So the membrane water flux increased significantly, while the BSA rejection rate decreased. When the addition amount of dodecanoyl-β-cyclodextrin was in the range of 2% to 3. 5%, the enantiomeric excess increased with the addition of dodecanoyl-β-cyclodextrin. A complete separation of racemic tryptophan can be performed using this novel dodecanoyl-β-cyclodextrin/polysulfone chiral membrane-based separation system.

Construction and characterization of an attenuated recombinant Listeria monocytogenes vector vaccine delivering HPV16 E7 / 生物工程学报

Listeria monocytogenes (L. monocytogenes, LM) is an excellent tumor vaccine vector. In this study, recombinant LM vaccine candidate expressing human papillomavirus type 16 (HPV16) E7 protein was constructed and its charactericts were determined. Through homologous recombination, E7 gene was cloned in frame with the LM4 Phly promoter-signal sequence, and introduced into the chromosome of LM4. The recombinant strain named LM4△hly::E7 with the plasmid-free and antibiotic-resistant gene-free was constructed. LM4△hly::E7 could express and secrete E7-LLO fusion protein; its size is 66 kDa and has immunological activity. Furthermore, LM4△hly::E7 could multiply in RAW264.7 macrophages by confocal laser scanning microscope. Additionally, LM4△hly::E7 could induce specific antibodies against E7 in immunized mice in ELISA. Also, the 50% lethal dose (LD₅₀) of LM4△hly::E7 strain was 3.863×10⁹ CFU (Colony-Forming Units) in C57BL/6 mice with intraperitoneal immunization, which was more attenuated than wild type LM4. Mice immunized with LM4△hly::E7 did not show obvious pathological change. These data show that LM4△hly::E7 expressing E7-LLO fusion protein has good safety, which may provide the materials for research of antitumor effect and would be a promising vaccine candidate for cervical cancer.

Progress of Listeria monocy togenes as tumor vaccine vector / 中国人兽共患病学报

Listeriamonocytogenes is a facultative intracellular bacterium that enters professional antigen presenting cells , presents passenger antigens to the major histocompatibility complex class I and II pathways ,then elicits CD+4 and CD+8 T-cell-mediated immune responses .It was demonstrated that attenuated Listeriamonocytogenes as a novel live vaccine vector in deliv-ering tumor antigens of cervical cancer and melanoma etc .,could induce strong protective immune response ,and shows effec-tive antitumor immunotherapeutics .This review discussed the characteristics of immune responses elicited by Listeria monocy-togenes ,and the progress of its antitumor immunotherapeutics as delivery vaccine vector .

Epidemiology of listeriosis infection in humans and animals, China, 2002-2012 / 中国人兽共患病学报

The prevalence of human and animal listeriosis for nearly 11 years in China was investigated in this study . The literature information about listeriosis in China from 2002 to 2012 was collected through retrieval system to make clinical and epidemiological statistical analysis of listeriosis .Cases of listeriosis were reported in 27 (79% ) provinces of China .The re-sult showed that animal listeriosis was reported for 123 times ,among these reports ,most were from pigs (39% ) ,and the sheep was in second place .Central nervous system infection was the main clinical manifestation of listeriosis in animals (72% ) . For human listeriosis ,84 clinical cases of listeriosis were reported ,including 35% cases in non-perinatal stage and 65% cases in perinatal stage .The main clinical manifestation of listeriosis was septicemia (51% ) .According to the result of investigation about listeriosis based on literatures information ,Listeriamonocytogenes caused humans and animals listeriosis annually ,which were reported in most provinces of China .The epidemic characteristics for listeriosis suggested that it was essential to strength-en the prevention and control of listeriosis .