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Objective: The purpose of this study is to reduce the colonization level of Campylobacter jejuni in chicken intestine by oral immunization of recombinant Lactococcus lactis expressing the ferric enterobactin receptor CfrA of C. jejuni., Methods: The whole cfrA gene and its N-terminal fragments were amplified by PCR, inserted into the expression vector pNZ8149 and transformed into L. lactis NZ3900. Based on the expression of CfrA in recombinant L. lactis by Western blot, the expression level was optimized by screening nisin concentration, induction temperature and time. Then the recombinant L. lactis strains were used to orally immunize specific-pathogen-free chickens. After oral immunization, the duration of recombinant L. lactis in chickens was determined by PCR, and the antibody levels of anti-CfrA serum IgG and intestinal mucosal sIgA were measured by ELISA. Finally, the immunized chickens were orally inoculated with C. jejuni to evaluate the inhibitory effect of recombinant L. lactis on colonization of C. jejuni., Results: Western blot results determined that the whole cfrA gene and its N-terminal fragments were both expressed in recombinant L. lactis in soluble forms whereas no secreted CfrA protein was detected outside bacterial cells. The optimal conditions for inducing the expression were grown at 37℃ for 1 h with nisin concentration of 25 ng/mL. Detection of chicken cloacal swabs showed that the duration of oral L. lactis was less than 10 days in chicken. The immunized groups produced higher antibody titers of anti-CfrA specific serum IgG and mucosal sIgA than the control groups. Moreover, the colonization rate of C. jejuni in the immunized groups was significantly lower than that in the control groups., Conclusion: Oral immunization of chickens with recombinant L. lactis expressing CfrA inhibited the colonization of C. jejuni. Our findings can be useful to develop oral vaccines with recombinant Lactobacillus for control of C. jejuni infection in chickens.

Objective: To understand the influence of meteorological factors on Oncomelania density in natural condition and provide scientific evidence for the control of the spread of schistosomiasis and Oncomelania., Methods: Based on the Oncomelania survey data in spring and ground meteorological observation data of Qianjiang from 1990 to 2014, the first-order autoregressive analysis method was used for trend fitting and disassemble, and the correlation between the change rate of Oncomelania density and various meteorological factors in different periods were analyzed., Results: The greatest influence of meteorological factors on Oncomelania density was temperature, followed by precipitation. The average minimum temperature in January and from December to February had predominant influence on Oncomelania density and frame occurrence rate of living Oncomelania (FORLO) respectively. The rise (fall) of average minimum temperature in January by 1 °C would lead to the increase (decrease) of Oncomelania density by 5.080%-6.710%; The rise (fall) of average minimum temperature from December to February by 1 °C would lead to the increase (decrease) of FORLO by 15.521%-15.928%. The period with the biggest influence of precipitation on Oncomelania density was from November to April, as the rainfall declined >20%, drought might occur, which would cause the reduction of Oncomelania density. Sunshine from September to November had some correlations with the change of Oncomelania density and FORLO. Statistical regression models for the change of Oncomelania density, FORLO and meteorological factors based on correlation analysis were established respectively., Conclusion: Weed removal in Oncomelania areas before December is beneficial to reduce the surface temperature and soil moisture content, which would result in Oncomelania density reduction in some extent. It' s notable that the winter temperature is in rise in Hubei province along with global climate change, causing the Oncomelania density to increase, to which more attention should be paid.

Objective: To investigate the effects of ephedrine combined with various doses of naloxone on neural plasticity in rats after cerebral ischemia/reperfusion injury to explore the possibility of synergistic effect about ephedrine combined with naloxone, promoting the optimum ratio of neural remodeling and its molecular mechanism., Method: A total of 192 healthy adult Sprague-Dawley rats, 220-250 g, were used to establish models of left middle cerebral artery occlusion using the suture occlusion method. Were randomly divided into 8 groups: the rats were intraperitoneally injected with 1.5 mg x kg(-1) x d(-1) ephedrine (ephedrine group), with 0.1, 0.2, 0.3 mg x kg(-1) x d(-1) naloxone (low, moderate and high doses of naloxone groups) , with 1.5 mg x kg(-1) x d(-1) ephedrine + 0.1, 0.2, 0.3 mg x kg(-1) x d(-1) naloxone (ephedrine + low, moderate and high doses of naloxone groups), and with 0.5 mL saline (model group), respectively. At 1-4 weeks following cerebral ischemia, sensorimotor integration in rats was assessed using the beam walking test, brain-derived neurotrophic factor (BDNF) expression was detected in the hippocampal CA3 area using immunohistochemistry 1-4 weeks after surgery, immunofluorescence method of detecting ischemic hemisphere hippocampal expression, The number of nerve cells apoptosis was detected using TUNEL assay., Result: BWT, BDNF, TUNEL assay results showed three doses of naloxone group had no significant effect, the effects increased together with the quantitative ephedrine, and had the amount-effect relationship, in which ephedrine + high dose of naloxone group the recovery of movement was fastest, BDNF expression in the best and ischemic apoptosis in the hippocampus at least, ischemic injury to the minimum, speed up the process of neural remodeling., Conclusion: The ephedrine and ephedrine + naloxone groups were accelerated motor function recovery rate in rat after cerebral ischemia, and the promotion of neural remodeling is closely related to the expression of BDNF, inhibit apoptosis in ischemic area, and with the increase of naloxone amount of additives, its role more clearly, the mechanism may be related to the dose of naloxone can significantly inhibit the ischemic area of apoptosis in early cerebral ischemia, so had the positive synergy effect with ephedrine to speed up the formation of neural remodeling.

Objective: To investigate the expression of RhoA mRNA in colorectal neoplasms., Methods: Total RNA was extracted from 42 surgically resected specimens of colorectal caricinoma and normal mucosa close to the lesions. Afier the optimal reverse transcription polymerase chain reaction (RT-PCR) condition was found, the mRNA expression levels of the RhoA gene in the lesions and the normal mucosa were examined semi-quantitatively and the relation between these expression levels and clinical pathological markers was compared., Results: The expression of RhoA gene mRNA in lesion of colorectal carcinoma was significantly higher than that in contiguous normal mucosa (1.8 +/- 0.6 vs 0.9 +/- 0.4, P < 0.01). The ratio of RhoA expression in neoplasm to that in contiguous mucosa was 2.02 +/- 0.82. Based on this ratio the 42 patients were divided into two groups: overexpression group (19 cases) and high-expression group (23 cases). In the overexpression group the lesions of 14 cases were in Dukes C and Dukes D stages, and lymph node metastasis was found in 13 cases. In the high-expression group, only 9 out of the 23 cases were in advanced stage and 8 cases showed lymph-node metastasis. Chi-squared test analysis demonstrated a significant difference in both aspects between these two groups (P < 0.05). The difference in number of metastatic lymph nodes between the two groups was statistically significant (P < 0.01). Mutation was not found in the RhoA gene sequence examined., Conclusion: RhoA gene may play an important role in colorectal carcinogenesis and correlate with invasion and metastasis of colorectal carcinoma.