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Objective To provide reference values for bone mineral density(BMD)in different skeletal regions of female Wistar rats at different ages. Methods Thirty SPF female Wistar rats were selected. The BMD of different skeletal regions(skull,upper limbs,thighs,trunk,ribs,pelvis,spine and the whole body)was measured by dual energy X-ray absorptiometry(DXA)at 6,10,12,24 and 30 months of age. The bone mineral densities between different age groups and that of different skeletal regions in the same age groups were compared. Results The BMD of the skull,upper limbs,thighs,trunk,ribs,pelvis, spine and the whole body was increased rapidly with age, and reached a peak at 10 months of age. The BMD of the skull,upper limbs,thighs,trunk,ribs were significantly higher than the whole body BMD in the same month-age group(P< 0.05 or P< 0.01). However,there was no significant difference between the pelvic, spine and the whole body BMD(P> 0.05). There was a significant positive correlation among the three correlations(P<0.01). Conclusions Some background data are provided for the bone biology studies of female Wistar rats, and provide useful supplementary reference for the studies of bone metabolism in rats and their application in biomedicine.
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Objective To establish a safe and effective method of rhesus monkey biopsy to take liver and kidney samples under B-mode ultrasound guidance. Methods A total of 4 adult monkeys(weight:8-12 kg; sex: male; age:11 -12 years old)were anaesthetized with 5 -10 mg/kg of ketamine hydrochloride for each through intramuscular injection. After successful anesthesia, abdominal shaving and iodophor disinfection, they were monitored from intercostal area of right upper quadrant or lateral waist subcostal abdomen portions to find liver or kidney organ by MyLab 30CV B-mode ultrasonography with 3.5 Hz transducer which was fixed with a guiding frame. Large vessels such as the portal vein and inferior vena cava were carefully avoided. The range of the biopsy gun was set to 15 mm. When the puncture target and the puncture needle were positioned in the guide line, the puncture target was perpendicular to the puncture needle, and then the trigger button of the puncture needle was pressed to obtain the liver or kidney tissue samples respectively. After puncture,the needle was pulled out quickly. The obtained liver and kidney tissues were used to extract RNA. Results About 13 mg of liver or kidney tissue was obtained by each puncture with volume convertion. This method was fast,reliable and safe,and the total RNA had high purity and integrity. There was no postoperative bleeding and infection. Conclusions This is a very important method for obtaining liver and kidney tissue samples of rhesus monkeys with the guidance of ultrasound. With this method, the research cost can be reduced, the life quality and animal welfare of laboratory non-human primates can be improved,and the accuracy of experimental result can be ensured.
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Objective To explore the feasibility of establishing a tree shrew model of chronic gastrointestinal mucosal injury. Methods A total of 12 adult male tree shrews were randomly divided into 3 groups. The experimental groups 1 and 2 were administered with intraperitoneal injection of 2 mg/(kg·d)and 1 mg/(kg·d)of 1-methyl-4-phenyl-1,2, 3,6-tetrahydropyridine(MPTP)once every day for 56 days, respectively. The control group was given the same volume of sterile saline at the corresponding time points. Changes in the body weight of the tree shrews were observed. The contents of dopamine in the cerebrospinal fluid were detected. Gastrointestinal morphology was observed by stereoscope and histopathological changes of the gastrointestinal mucosa were examined by HE staining. Results The body weight and the contents of dopamine in the cerebrospinal fluid of the tree shrews in the model group were significantly decreased(P< 0.05 for both). Pathological changes to some extent of the gastric antrum, the gastric body and the duodenum were observed, without obvious differences between the 2 mg/kg group and the 1 mg/kg group. No obvious changes were found in the control group. Conclusions Long-term intraperitoneal injection with a low dose of MPTP is a feasible method for the establishment of a tree shrew model of chronic gastrointestinal mucosal injury. The optimal dose is 2 mg/(kg·d)every day for 56 days.
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Many researchers employed mammalian expression system to artificially express cannabinoid receptors, but immunoblot data that directly prove efficient protein expression can hardly be seen in related research reports. In present study, we demonstrated cannabinoid receptor protein was not able to be properly expressed with routine mammalian expression system. This inefficient expression was rescued by endowing an exogenous signal peptide ahead of cannabinoid receptor peptide. In addition, the artificially synthesized cannabinoid receptor was found to aggregate under routine sample denaturing temperatures (i.e., [Symbol: see text]95°C), forming a large molecular weight band when analyzed by immuno-blotting. Only denaturing temperatures [Symbol: see text]75°C yielded a clear band at the predicted molecular weight. Collectively, we showed that efficient mammalian expression of cannabinoid receptors need a signal peptide sequence, and described the requirement for a low sample denaturing temperature in immuno-blot analysis. These findings provide very useful information for efficient mammalian expression and immuno-blotting of membrane receptors.
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OBJECTIVE Based on the epidemiologic data, to provide the effective measures to control nosocomial infection in field hospital. METHODS The views in literatures on medical treatments in war conditions and the practical measures for control and prevention of nosocomial infection were summarized. RESULTS Nine steps must be taken in order to effectively control and prevent nosocomial infection, including making plans and measures, preparing important materials, training medical staff, prevention educating, sterilizing, cutting off pathogenic source, monitoring, reasonable antibiotics applying, and protecting susceptible people. CONCLUSIONS In field hospital, effective prevention and control of nosocomial infection is the premises of improving healing rate and rejoining rate of the wounded.