Exposing males to female scent increases the cost of controlling <Emphasis Type="Italic">Salmonella</Emphasis> infection in wild house mice

Secondary sexual characters often provide indicators of a male’s resistance to infectious diseases to rivals and potential mates, but it is unclear why. It is often suggested that males honestly signal their health due to energetic and other physiological trade-offs between investing into secondary sexual traits vs resistance to infectious diseases. Our aim was to determine whether such a trade-off exists using wild-derived male house mice (Mus domesticus). We exposed male mice to female scent, a manipulation that induces elevations in testosterone concentration and the expression of a variety of testosterone-mediated secondary sexual traits, and tested whether this sexual stimulation impaired the males’ ability to resolve or cope with an experimental infection (Salmonella enterica). We kept the males on a controlled diet to prevent them from compensating by eating more food. We found that sexually stimulated males were able to control bacterial growth as effectively as sham-stimulated controls; however, to do so, they lost more body mass during infection compared to the controls. In contrast, we found no evidence that sexual stimulation reduced the body mass of uninfected male mice. These results indicate that males’ responses to female odor are not immunosuppressive per se, yet they increase the energetic costs of controlling infection. Our findings support the idea that there is a physiological trade-off between secondary sexual signaling vs resistance to infectious diseases and suggest that studies using only immunocompetence assays might fail to detect such energetic trade-offs. We dedicate this paper to the late Professor Chris Barnard who conducted pioneering research on this topic.     

Dietary Spirulina platensis alleviates aluminum and aluminum fluoride induced histopathological and biochemical alterations in mice kidney

Aluminum and its salts widely used in our daily life have been reported nephrotoxic to humans and animals following prolonged exposure. Therefore, the present study was made to examine the renoprotective role of Spirulina platensis against Al³⁺ and AlF₃ in male Swiss albino mice. Exposure to these chemicals decreased feed and water intake, and body and kidney weights. Histology of kidney and their biochemistry were also markedly altered along with that of serum biochemistry. Spirulina not only minimize toxic effects of test chemicals but also favored faster recovery of treated mice after their withdrawal.     

五氯酚钠对雄性小鼠的生殖毒性作用

为研究五氯酚钠(PCP-Na)对雄性小鼠的生殖毒性作用,将100只昆明雄性小鼠随机分为5组:3个染毒组、1个阴性对照组(蒸馏水)和1个阳性对照组(环磷酰胺40mg·kg-1).以不同剂量(13.44、26.88、53.76mg·kg-1)PCP-Na经口染毒,连续染毒5d,每天1次.染毒结束后第2d和第23d分两批处死动物,检测精子数量、精子畸形率以及睾丸、附睾重量及其脏器系数的变化.结果表明,PCP-Na染毒结束后第2d,与阴性对照组相比,高剂量组(53.76mg·kg-1)精子畸形率显著增加(p<0.05),睾丸、附睾重量及附睾系数显著下降(p<0.05),其他指标无显著变化(p>0.05).中、低剂量组(26.88、13.44mg·kg-1)各检测指标与阴性对照组均无显著性差异(p>0.05);PCP-Na染毒结束后第23d,与阴性对照组相比,高剂量组(53.76mg·kg-1)精子畸形率显著增加、精子密度显著减少、睾丸和附睾重量显著下降(p<0.05),中剂量组(26.88mg·kg-1)附睾重量显著下降(p<0.05),其他指标均无显著变化(p>0.05);PCP-Na引起的精子畸形以头部畸形为主,主要为无定形,其次为无钩形、香蕉形和尾折叠.以上结果提示,在本实验条件下,PCP-Na对雄性小鼠具有明显的生殖毒性.     

Varying levels of female promiscuity in four <Emphasis Type="Italic">Apodemus</Emphasis> mice species

Sexual selection in most vertebrates is based on the evolution of fitness optimization strategies such as multiple-male mating (MMM). Several ecological correlates of MMM have been identified in bird and fish populations; however, only few studies have documented the effects of environmental change on promiscuity in mammals. In this study, the 127 pregnant females from four central European and ecologically diverse species of field mice (genus Apodemus) were studied to assess the role of ecological factors that may have shaped the evolution of particular mating systems. MMM was found in all analyzed species: in Apodemus uralensis and Apodemus flavicollis, up to two males could be identified as the fathers of a particular litter, while three males sired 9.1% of analyzed litters of Apodemus sylvaticus and 20.6% of Apodemus agrarius. Furthermore, there were obvious differences between species in relative testes size and the proportion of multiple sired litters during those seasons when the opportunity for multiple mating was high. The species with the smallest testes and the least promiscuous was A. uralensis (only 43.5% of multiple sired litters), while the species with the biggest testes and the most promiscuous was A. agrarius (69.2%). MMM was significantly associated with higher litter size in A. flavicollis, and the probability of MMM strongly increased with season in A. agrarius and with abundance in A. uralensis. These results indicate that ecological factors are associated with MMM rates in Apodemus field mice and more research is needed to fully understand the evolution of mating strategies at different levels of biological resolution.     

重组BALB/C鼠冷诱导RNA结合蛋白CIRP多克隆抗体的制备与鉴定

冷诱导RNA结合蛋白(CIRP)是第一种在哺乳动物细胞中被发现的冷休克蛋白,伴随着细胞冷应激过程过量表达.为进一步研究冷诱导RNA结合蛋白CIRP的生物学功能,构建重组BALB/C鼠CIRP的原核表达载体,重组BALB/C鼠CIRP蛋白经NI-NTA亲和树脂纯化后免疫獭兔制备抗CIRP多克隆抗体,以间接ELISA和Western blot检测抗体效价和抗原特异性.本实验成功构建了CIRP的原核表达载体,在E coli XL-1-blue得到了高效表达,利用原核表达包涵体蛋白免疫獭兔获得了高效价的CIRP多克隆抗体,该抗体能识别肝脏和睾丸中天然的CIRP蛋白.图5参14     

羟基化多溴联苯醚(OH-PBDEs)在小鼠肝脏微粒体的体外代谢及对CYP450酶活性的影响

羟基化多溴联苯醚(OH-PBDEs)是一类具有内分泌干扰效应的酚类化合物,生物毒性要高于母体多溴联苯醚(PBDEs),研究OH-PBDEs的体外代谢行为对于理解其在生物体内的富集转化具有重要意义。以小鼠肝脏微粒体作为研究对象,考察了3-OH-BDE-47、5-OH-BDE-47、6-OH-BDE-47和2’-OH-BDE-68在小鼠肝脏中的体外代谢,并分别研究了浓度为0.1、0.2、0.4、0.6、1.0μmol·L-1条件下4种OH-PBDEs对细胞色素P450酶系中7-乙氧基香豆素-O-脱乙基酶(ECOD)、7-乙氧基异吩唑酮-O-脱乙基酶(EROD)和苯胺4-羟基化酶(ANH)活性的影响。结果表明,4种OH-PBDEs在小鼠肝脏微粒体中均能够快速代谢,代谢率分别为80%(3-OH-BDE-47)、42%(5-OH-BDE-47)、86%(6-OH-BDE-47)和63%(2’-OH-BDE-68)。实验所设OH-PBDEs各浓度对微粒体的ECOD活性无显著性抑制作用,但对EROD的活性均表现出相同的显著抑制作用;4种OH-PBDEs表现出不同的ANH活性影响,即3-OH-BDE-47对ANH活性具有抑制作用,5-OH-BDE-47具有诱导作用,而6-OH-BDE-47和2’-OH-BDE-68对ANH活性无显著性影响。     

敌百虫致小鼠外周血淋巴细胞DNA-蛋白质交联作用研究

为探讨敌百虫致DNA-蛋白质交联作用,以昆明小鼠为受试动物,敌百虫按0、20、40、60 mg·kg^-1四个剂量水平,灌胃染毒小鼠两周。第五组以提取的正常小鼠外周血淋巴细胞经50 μmol·L^-1的H2O2处理为阳性对照组。采用经改进的彗星试验方法来检测染毒后外周血淋巴细胞DNA-蛋白质交联效应。结果表明,与空白组相比,各敌百虫染毒组都能引起DNA损伤作用(p<0.01)并引起一定程度的DNA-蛋白质交联效应,在较高浓度(40、60 mg·kg^-1）时DNA-蛋白质交联尤为明显,存在一定的潜在突变风险。     

PTA wastewater molecular toxicity detected with gene chip

The purified terephthalic acid （PTA） petrochemical wastewater molecular toxicity detected by use of Mouse Genome 430A 2.0 GeneChip was conducted in this research. The toxic dose to male mice was 0.03 g/（kg, d） of PTA in the wastewater. The mice liver total RNA was isolated as the temple for synthesis of eDNA and then the cDNA as the temple for synthesis of cRNA. Hybridizing the cRNA with the target genes on the gene chip, there were 232 genes expression levels up-regulated and 74 genes down-regulated discovered obviously. The foremost 40 genes for both the highest and the lowest expression levels involved endogenetic steroid and hormone metabolism, immune system, the leukocyte activity and inflammation, detoxification in liver, reproduction and growth hormone, regulation immune factors of anti-tumor and anti-infection and cancer to the mice sampled. The data suggest the PTA wastewater contained over 5 aromatics and their toxicities integrated were much higher than the pure chemical PTA. And the pure chemical PTA toxicities data cannot be used to evaluate the toxicity of the PTA wastewater instead.     

氰戊菊酯与辛硫磷混合杀虫剂(农满忆)对雄性小鼠精子畸形率和生殖细胞微核率的影响

为初步探讨氰戊菊酯与辛硫磷混合杀虫剂(农满忆)对雄性小鼠生殖细胞的损伤效应,将该杀虫剂对小鼠进行灌胃染毒5d,于第6d取小鼠睾丸细胞进行微核试验并采用精子畸形实验检测小鼠不同时期(第6、14、36d)精子畸形率的改变.结果表明,与对照组相比,该杀虫剂中、高剂量组(60、120mg·kg-1)小鼠睾丸细胞微核率均显著升高(p<0.05),而低剂量组(30mg·kg-1)微核率没有显著变化(p>0.05);中、高剂量组均能诱导小鼠不同时期精子畸形率显著升高(p<0.05),而低剂量组精子畸形率变化不显著(p>0.05).因此,氰戊菊酯与辛硫磷混合杀虫剂能够使雄性小鼠精子畸形率增加并造成雄性生殖细胞微核率升高,有一定的致突变作用.     

聚苯乙烯微塑料对糖尿病小鼠肾脏的影响

以糖尿病小鼠为模式生物,探究了100nm和5μφ的聚苯乙烯微塑料(PSMPs)(200μg/L)通过饮水暴露28d后对小鼠肾脏的毒性.结果表明,糖尿病小鼠对PSMPs的暴露更加敏感,100nm和5μm PSMPs暴露导致糖尿病小鼠肾脏出现明显的炎性细胞浸润和淤血等病理损伤,且 100nm PSMPs对肾脏造成的病理损伤...