Effect of T-activin on thymus involution in mice

The effect of T-activin on thymus involution in mice was studied. T-activin in a dose of 1.0 micrograms/mouse was injected into young male (CBA X C57BL)F1 mice weighing 24.0 +/- 2.0 g daily for 20 days. Morphometric analysis of the thymus was made 6 months after the treatment with T-activin was completed. It was found that T-activin induced the suppression of physiological involution of the thymus together with the enhancement of the processes of thymocyte transformation and proliferation.     

无创性肢体缺血预适应对小鼠抗应激能力的影响

目的:探讨无创性肢体缺血预适应在提高小鼠抗应激能力方面的作用。方法:小鼠分为正常组、对照组、预适应组和药物组,进行常压耐缺氧、耐疲劳负重游泳、耐高、低温实验,分别记录各种应激状态下小鼠的耐受时间,测定常压缺氧耐受后小鼠血清中SOD的活性和负重游泳后血清中乳酸的含量。结果:预适应组能显著提高小鼠常压耐缺氧时间,且SOD活性较对照组有显著的提高,但提高的程度均低于普萘洛尔组。预适应组平均游泳时间显著延长,且程度与咖啡因组相当。预适应能明显延长高温下小鼠的存活时间,且延长程度与氯丙嗪没有显著性差异。与正常组比较,预适应组能显著延长小鼠的耐低温时间。结论:无创性肢体缺血预适应能提高小鼠耐缺氧、抗疲劳、耐高温和耐低温的能力。     

Effects of ionizing radiations on the ultrastructure of the thymus gland

Different doses of gamma rays induce ultrastructural alterations in limphoid and epithelial cells of the chick thymus which exhibit a different temporal evolution after the treatment. The main changes which occur in lymphoid cells treated with 50 rads disappear 48 hours after the irradiation, while with 100 rads the radiation damage is still evident in epithelial cells.     

Effects of endotoxin (lipopolysaccharides) on experimental aspergillosis in leukemic mice

In an attempt to evaluate effects of bacterial endotoxin on systemic fungal infection, experimental systemic Aspergillus infection was induced in leukemic mice (AKR strain) with (Group B) or without (Group A) preceding intraperitoneal administration of Pseudomonas aeruginosa derived lipopolysaccharides. All mice in group A died within 4 days after intravenous inoculation of Aspergillus fumigatus spores and developed extensive and disseminated fungal lesions without inflammatory reactions. In contrast, 5 of 10 mice in group B were alive at day 4 and 1 mouse in group B was alive when the experiment was terminated on the 14th day. These mice showed less extensive fungal lesions with definite, albeit minimal, inflammatory reactions which were composed of macrophages and neutrophils. In addition, serum iron levels and iron saturation rates were significantly lower in mice in group B than in group A. These results indicate that P. aeruginosa endotoxin has a deterring effect on systemic Aspergillus infection in leukemic mice.     

Effect of chorionic gonadotropin on the structure and endocrine function of the thymus gland in mice

The thymic secretory function changes in the pubertal female mice under the influence of chorionic gonadotrophin (CG). The latter is activated after administration of hormone in doses, corresponding to its levels in animals in different terms of pregnancy and is depressed with doses, greatly exceeding those levels. The lack of the effect in thymectomized mice testifies to the realization of the modulating CG action at the thymus level. Changes of mass and cellularity of the thymus and spleen reflect dose-dependent alteration of the thymocyte migration rate.     

Effect of T-activin on peripheral immunity organs in intact and thymectomized mice

Morphometry of the spleen, axillary lymph nodes and cytological assay of the bone marrow and peripheral blood were performed in (CBA X C57BL)F1 mice 1, 5, 10 and 15 days after subcutaneous injection of 0.5 microgram T-activin to intact and thymectomized (when adult) mice 2 months after operation. It was demonstrated that in intact animals, injection of T-activin stimulated the whole system of immunogenesis. The time course of plasmatization and the response of the germinative centers differing from that seen during antigen administration suggests that T-activin is not immunogenous, acting as a stimulant of the previous immune responses. The permanent amount of the degenerating cells attests to the lack of the toxic drug effect.     

Effects of smoking on the lower respiratory tract microbiome in mice

Background

Recent studies break with traditional opinion that the lower respiratory tract is sterile, and increasingly focus on the lung microbiome and disease. Smoking, as an important etiology of inflammatory lung disease, was considered as a factor influencing lung microbiome variations in our study, and we aimed to study the effect of smoking on inflammation and microbial diversity and community.

Methods

Forty male mice were selected and randomly divided into a smoking and a non-smoking group. Mice in the smoking group were exposed to smoke smog for 2?h/day for 90?days. Blood and lung tissues were obtained after the experiment, and ELISA was used to measure interleukin-6 and C reactive protein concentrations. 16S rRNA gene quantification and sequencing technology were used to compare microbial diversity and community between the two groups. SAS 9.1 and R software were used to analyze the data.

Results

Thirty-six mice survived, and the weight of the smoking group increased more slowly than that of the non-smoking group. Denser inflammation and congestion were observed in the lungs of the smoking mice compared with the non-smoking group Higher microbial diversity was observed in the smoking group, and Enterobacter, Acidimicrobiales_norank, and Caulobacteraceae_Unclassified genus were significantly more abundant in the non-smoking group (P?<?0.001).

Conclusions

Smoking altered microbial diversities and communities in the lower respiratory tract of mice. Microbial variation should be considered in future studies focusing on smoking-induced inflammatory disease.