The tigecycline resistance gene tetX has an expensive fitness cost based on increased outer membrane permeability and metabolic burden in Escherichia coli.

Livestock-derived tetX-positive Escherichia coli with tigecycline resistance poses a serious risk to public health. Fitness costs, antibiotic residues, and other tetracycline resistance genes (TRGs) are fundamental in determining the spread of tetX in the environment, but there is a lack of relevant studies. The results of this study showed that both tetO and tetX resulted in reduction in growth and an increased in the metabolic burden of E.

CMKLR1 deficiency maintains ovarian steroid production in mice treated chronically with dihydrotestosterone.

Elevated serum chemerin levels correlate with increased severity of polycystic ovary syndrome (PCOS). However, the role of CMKLR1 signaling in ovarian biology under conditions of excess DHT remains unclear. In this study we compared the effects of continuous 90-day high dose DHT exposure (83.

An all permanent magnet electron cyclotron resonance ion source for heavy ion therapy.

A high charge state all permanent Electron Cyclotron Resonance ion source, Lanzhou All Permanent ECR ion source no. 3-LAPECR3, has been successfully built at IMP in 2012, which will serve as the ion injector of the Heavy Ion Medical Machine (HIMM) project. As a commercial device, LAPECR3 features a compact structure, small size, and low cost.

[Molluscicidal effect of buried niclosamide sustained-release method in plateau mountainous areas].

Objective: To evaluate the molluscicidal effect of the buried niclosamide sustained-release method in Oncomelania snail-infested terraced environments of mountainous areas in Yunnan Province.

Methods: A piece of relatively isolated snail-infested terraced environment was selected as experimental plot and randomly divided into four groups. The buried niclosamide sustained-release methods were performed in Group A, B, C with the doses of 6 g/m2, 12 g/m2, 24 g/m2 respectively, and Group D was sprayed with 50% niclosamide ethanolamine salt wettable powder (2 g/m2) as the control.

[Measuring the estrus cycle and its effect on superovulation in mice].

This study compares superovulation efficiency during different stages of the estrus cycle in mice by investigating the pudendum appearance, vaginal epithelial cell type, and the follicular development dynamics, in relation to the estrus cycle. We determined the stages of the estrus cycle by observing the pudendum and making vaginal smears of the Kunming mouse, and ascertaining the follicular development by making paraffin sections. Based on the observation, mice in stages of proestrus, oestrus, metoestrus and dioestrus were superovulated respectively, and their follicular developments and embryo collection results were tracked to ascertain the appropriate estrus cycle stage for superovulation.

[Somatic nuclear transplantation and serial nuclear transplantation of human finger-domain lacking t-PA gene in goat].

In order to research developmental competence of transgenic somatic cell by serial nuclear transplantation, goat cloned embryos were compared with recloned embryos in ability of in vitro development. Fetal fibroblasts including human finger-domain lacking t-PA gene was microinjected into cytoplasm of the MII oocytes. Goat embryos (G0) were cloned by this procedure.

Nitric oxide affects preimplantation embryonic development in a rotating wall vessel bioreactor simulating microgravity.

Microgravity was simulated with a rotating wall vessel bioreactor (RWVB) in order to study its effect on pre-implantation embryonic development in mice. Three experimental groups were used: stationary control, rotational control and clinostat rotation. Three experiments were performed as follows.