Effects of Bacillus subtilis B10 spores on viability and biological functions of murine macrophages

This study was conducted to investigate the effects of Bacillus subtilis B10 spores on the viability and biological functions of murine macrophage. RAW 264.7 cells were stimulated both with and without B. subtilis B10 spores for 12 h. Then cell viability was determined to evaluate the cytotoxic effect of B. subtilis B10 spores to the cells, and the activities of acid phosphatase (ACP) and lactate dehydrogenase (LDH), the production of nitric oxide (NO) and inducible nitric oxide synthase (iNOS), and the secretion of inflammatory cytokines were measured to analyze the functions of macrophages. The results showed that B. subtilis B10 spores were not harmful to RAW 264.7 cells and they also strongly enhanced the activities of ACP and LDH (P < 0.01), remarkably increased NO and iNOS production (P < 0.01), and significantly stimulated the secretion of pro‐inflammatory cytokines, including tumor necrosis factor‐alpha (TNF‐α), interferon‐gamma (IFN‐γ), interleukin‐1 beta (IL‐1β), IL‐6, IL‐8 and IL‐12 (P < 0.01) while they reduced anti‐inflammatory cytokine IL‐10 (P < 0.01). The outcomes suggest that B. subtilis B10 spores are not only safe for murine macrophages, but also can activate these cells and enhance their immune function. The above findings suggest that B. subtilis B10 spores are potentially probiotic.     

广东省蚕学会召开八届五次常务理事会议

广东省蚕学会于2007年4月23日在广州召开八届五次常务理事会议,11位常务理事出席会议,一位理事列席了会议。会议由林健荣副理事长主持,现将会议主要情况纪要如下:     

美洲大蠊i型溶菌酶基因的克隆及其功能预测

溶菌酶是昆虫先天性免疫系统的重要组成成分。以冈比亚按蚊i型溶菌酶氨基酸序列为种子序列,在美洲大蠊EST库中查找相似序列。通过RT-PCR和RACE PCR技术,克隆获得美洲大蠊i型溶菌酶基因。生物信息学分析表明,所克隆的溶菌酶基因片段长度为525bp,包括5’非编码区12bp,3’非编码区18bp和完整的开放阅读框495bp,其编码164个氨基酸,包括溶菌酶成熟肽137个氨基酸和27个信号肽氨基酸。经同源比对,它与黑腹果蝇和冈比亚按蚊的i型溶菌酶具有同源性,并且具备了异构肽活性的功能位点H,但缺失了抑菌活性的功能位点E/D/S,这为其功能和分子进化研究提供了重要的基础。     

动物科学专业实践教学环节教学效果的调查分析与改革思路

动物科学专业是我国高等农业院校均开设的一门传统专业课。动物科学专业所具有的实践性及应用性等学科特点,决定了实践教学环节在分析探讨其整个教学系统中占有非常重要的地位。对动物科学专业实践教学环节的教学效果进行了问卷调查,分析并探讨了其改革思路。结果表明,学生对该专业的实践教学环节总体上是满意的,但在专业技术综合训练及科研训练等方面,尚需在以后的教学方案改革中进一步完善。     

圈养蓝鹇和白鹇繁殖行为的时间节律观察

采用瞬时取样法对圈养的2对蓝鹇和2组白鹇繁殖期行为的时间节律进行了初步研究,分别选择蓝鹇和白鹇繁殖行为较为明显的时期,各记录15 d,即蓝鹇为2008年3月30日～4月15日(12、13日因故未观察),白鹇为2008年4月16～30日;每天观察12 h,即从7:00～19:00。结果表明第一组蓝鹇和白鹇的繁殖行为都明显少于第二组蓝鹇和白鹇,蓝鹇和白鹇的繁殖行为的发生次数随日期出现波动,两物种繁殖行为的高峰多在早晚时段。蓝鹇和白鹇的产蛋周期分别为3～4 d和1～3 d;两物种雌性个体在产蛋前均有较多繁殖行为发生;两物种的繁殖对配对个体日间发情的同时性要求均不高,白鹇的繁殖与配对个体繁殖行为发生的绝对频次多少也无关,蓝鹇的繁殖与配对个体繁殖行为发生绝对频次多少的关系尚不明确。     

Immunopathogenic behaviors of canine transmissible venereal tumor in dogs following an immunotherapy using dendritic/tumor cell hybrid

Canine transmissible venereal tumor (CTVT) is a naturally occurring tumor that can be transmitted between dogs via live tumor cell inoculation. It is also a spontaneous self-regression tumor and its behavior is closely related to host immune responses. Since CTVT had been widely used for tumor models in canine cancers, whether this self-regression may overtake the immunity elicited from an exogenous tumor vaccine remains unclear and certainly worthwhile to be investigated. In this study, we used DCs/tumor hybrids as a tumor vaccine to evaluate the CTVT model. We prepared mature allogeneic dendritic cells from bone marrow and then assessed their phenotype (CD80, CD83, CD86, CD1a, CD11c, CD40 and MHC II), antigen uptake and presenting abilities. Fused dendritic cell/CTVT hybrids were then used as a vaccine, administered three times at two-week intervals via subcutaneous injection near the bilateral auxiliary and inguinal lymph nodes. In comparison with unvaccinated dogs (spontaneous regressed group), within a period of 2.5 months, the vaccinations substantially inhibited tumor progression (p<0.05) and accelerated the rate of regression by a mechanism involving amplification of the host tumor-specific adaptive immune responses and NK cytotoxicity (p<0.001). Pathologic examination revealed early massive lymphocyte infiltration resulting in final tumor necrosis. In addition, there are not any detectable effects on routine physical, body temperature or blood chemistry examinations. In conclusion, our data furnishes a reference value showing that CTVT is a model of potential use for the study of immunity elicited by vaccines against tumors, and also enable early-phase evaluation of the dendritic cell/tumor vaccine in terms of raising host immunity.     

不同水钙磷浓度条件下草鱼对水和饲料中钙磷的吸收利用

本研究结果表明:草鱼对饲料钙磷的消化吸收受水中钙磷浓度的影响。草鱼能直接从水中吸收利用钙磷。鱼体存积的大部分来自于水,而磷则大部分从饲料中获得,草鱼钙磷的利用按Ca/P≈1.6的比值进行。     

覆盖对粘重土壤中苜蓿出苗的影响

紧实土壤降雨后常由于板结而严重影响作物出苗,导致建植不良乃至失败本实验采用遮阳膜覆盖、麦秸覆盖、不覆盖、土壤稳定剂４个表面处理和快速干燥、缓慢干燥２个干燥速度处理,研究芷蓉播后模拟降水条件一出苗情况,不同的覆盖及土壤处理条件下芷蓿出苗具有显著的处理效应,处理效应主要在出苗早期形成,遮阳膜覆盖比其他出苗显著要高;干燥速度地芷蓿出苗无影响。土壤剂和麦秸对苜蓿出苗的影响需要进一步的研究。     

汕头市猪场猪瘟和猪禽流感血清学监测报告

为了了解和掌握我市猪场的猪瘟免疫情况及感染高致病性禽流感疫病的可能性，我所分别于2005年2月和4月两次对全市范围内各类型的养猪场免疫猪瘟的猪只采集血清941份，进行猪瘟血清抗体监测和猪高致病性禽流感疫情血清学监测。现将监测结果报告如下。