Antiviral effects of selected IMPDH and DHODH inhibitors against foot and mouth disease virus.

Foot-and-mouth disease virus (FMDV) is an important pathogen that affects livestock breeding and causes huge economic losses worldwide. Currently, the development of antiviral agents to combat FMDV infection at the early stages is being explored. As viral replication critically depends on the host for nucleoside supply, host enzymes involved in nucleotides biosynthesis may represent potential targets for the development of antiviral agents. In the present study, the effects of IMP dehydrogenase (AVN-944 and mycophenolate mofetil) and dihydroorotate dehydrogenase (teriflunomide) inhibitors were evaluated both in vitro and in vivo. The results revealed that these compounds were effective in suppressing FMDV (O/MY98/BY/2010 and A/GD/MM/2013) infection. With regard to the antiviral mechanism, time-of-addition experiments revealed that these compounds were effective when added at the early stages of viral lifecycle (0-8 h post infection). However, exogenous guanosine/uridine eliminated the antiviral activity of these compounds. Importantly, treatment AVN-944 and teriflunomide significantly improved the survival of mice that were subcutaneously treated with FMDV. Together, the results of the present study indicate the broad-spectrum activities of anti-FMDV agents targeting IMP dehydrogenase or dihydroorotate dehydrogenase, which could be useful in developing strategies to prevent FMD.

Preparation of brain targeted immunoliposomes / 药学学报

To prepare a kind of effective non-viral transduction vector, which can deliver exogenous gene into the brain, this vector can be injected through vein system and has the ability to penetrate blood brain barrier. Several groups of materials proportion, type of oil phase, water-oil ratio, phosphatides-cholesterol ratio, temperature of steaming, ultrasonic temperature and time were compared for optimization. Well-constructed immunoliposomes encapsuling LacZ gene were infused into rats through tail vein. 48 h after injection, expression product beta-galactosidase of LacZ gene was detected by histochemistry staining to convince the validity of immunoliposomes as non-viral vectors. The best proportion of synthesis immunoliposomes is as following: phosphatides-cholesterol ratio is 1:1, lipids/drug is 100:1, the type of oil phrase is dichloromethane, oil-water ratio is 4:1, temperature of steaming is 30 degrees C, ultrasonic temperature and time is 10 degrees C and 5 min. At last, 10% trehalose was added as a stabilizer. The entrapment rate is 87.24% and antibody coupling rate is 69%. When immunoliposomes were infused into rats, the expression of LacZ gene could be observed in the brain and periphery organs. Through the best proportion of materials, gene delivering immunoliposomes had been synthesized successfully. This non-viral vector can deliver exogenous gene penetrating blood brain barrier and express in the brain, and will be well-used in the field of gene therapy of cerebral diseases.

Expression of galectin-3 in invasive prolactinomas / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the expression of galectin-3 (Gal-3) in prolactinomas.</p><p><b>METHODS</b>Expressions of Gal-3 were evaluated by immunohistochemistry using polyclonal antibody in 16 invasive prolactinomas and 16 prolactinomas.</p><p><b>RESULTS</b>Gal-3 was expressed both in invasive prolactinomas and noninvasive prolactinomas while significantly higher expression seen in the invasive prolactinomas (P < 0.05).</p><p><b>CONCLUSION</b>Gal-3 expression may be used as a useful indicator to determine the invasiveness and prognosis of prolactinomas.</p>

Recent advance in experimental study of cerebral ischemia treated by vascular endothelial growth factor / 中国医学科学院学报

Vascular endothelial growth factor (VEGF) has been found to be the most powerful angiogenic factor. Studies have shown that cerebral ischemia and hypoxia stimulate the expressions of VEGF and its receptors in the brain, while exogenous VEGF promotes the formation of new blood vessels in the ischemic brain penumbra, and reduce the volume of cerebral infarction. The effect of VEGF on cerebral ischemia was previously explained the mechanism that VEGF had a specific mitogenetic roles in cerebral endothelial cells and thus promoted neovascularization; however recent evidence has shown that VEGF also has direct effects on neural and glial cells. Its multiple protection roles on central nervous system involve vascularization, neurogenesis, direct neurotrophic and neuroprotective effect, as well as antiapoptosis effect, especially when brain ischemia occurs. Further elucidation of these mechanisms on central nervous system may serve as a key procedure in understanding the main aspects of neural repair and neural protection, and develop effective therapeutic measures for intervention in stroke.

Experimental study on the proliferation and plasticity of neural stem cells in situ in adult rats after cerebral infarction / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the proliferation and plasticity of neural stem cells in situ in adult rats after cerebral infarction.</p><p><b>METHODS</b>Cerebral infarction models of rats were made and the dynamic expression of bromodeoxyuridine (BrdU) and BrdU/polysialylated neural cell adhesion molecule (PSA-NCAM) were determined by immunohistochemistry and immunofluorescence staining.</p><p><b>RESULTS</b>Compared with the controls, the number of BrdU-positive cells in the subventricular zone (SVZ) and hippocampus increased strikingly at day 1 (P < 0.05), reached maximum at day 7, and decreased markedly at day 14, but it was still elevated compared with that of the controls (P < 0.05); The number of BrdU-labeled with PSA-NCAM-positive cells increased strikingly at day 7 (P < 0.05), reached maximum at day 14, and markedly decreased at day 28, but it was still elevated compared with that of the controls (P < 0.05), and was equal to 60% of the number of BrdU-positive cells in the same period.</p><p><b>CONCLUSIONS</b>Our results indicate that cerebral infarction stimulate the proliferation of inherent neural stem cells in situ and most proliferated neural stem cells represent neural plasticity.</p>