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To investigate the changes in cell autophagy and the molecular mechanism of rapamycin affecting the fracture healing.Sprague-Dawley (SD) rats were used to establish the right femoral shaft fracture models, and then underwent immunofluorescence assay to detect the autophagy level in bone tissues. After model establishment, SD rats were divided into two groups, the control group and the rapamycin group (1 mg/kg/d). Respectively, at the 2nd, 4th, and 6th week, rats were randomly selected from each group for X-ray and Micro-computed tomography (Micro-CT) examinations to determine callus growth, immunofluorescence assay to detect the protein expression of light chain 3 II (LC3 II), immunohistochemistry to evaluate the autophagy level through detecting the expression of Beclin1 in rats, Western blotting assay to detect cell apoptosis in tissues, hematoxylin and eosin staining (HE staining) to evaluate the osteoblastic activity through count of osteoblast in bone tissue at the end of fracture, and measure the expression of vascular endothelial growth factors (VEGF).Significant increases were seen in protein expression of cells in bone tissues at the end of fracture. In rapamycin group, callus formation and calcification level in rats were all higher than those in control group; compared with control group, for rats in rapamycin group, cell autophagy was significantly elevated in bone tissues, while cell apoptosis at the end of fracture was reduced with a significant increase in osteoblastic activity. The expression of VEGF in rapamycin group was higher than that in control group.Rapamycin can facilitate fracture healing through inducing cell apoptosis and suppressing cell apoptosis in bone tissues.

Multiparous early lactation Holstein cows (n = 16) were used in a randomized complete block design to determine the effects of feeding fatty acid calcium and the interaction of forage quality on production performance and biochemical indexes in early lactation cow. Treatments were as follows: (i) feeding low-quality forage without supplying fatty acid calcium (Diet A), (ii) feeding low-quality forage with supplying 400 g fatty acid calcium (Diet B), (iii) feeding high-quality forage without supplying fatty acid calcium (Diet C) and (iv) feeding high-quality forage with supplying 400 g fatty acid calcium. This experiment consisted 30 days. The milk and blood samples were collected in the last day of the trail. Intakes were recorded in the last 2 days of the trail. Supplementation of fatty acid calcium decreased significantly dry matter intake (DMI) (p < 0.01). Addition fatty acid calcium decreased milk protein percentage (p < 0.01) and milk SNF percentage (p < 0.01), but increased MUN (p < 0.05). Supplemented fatty acid decreased concentration of blood BHBA (p < 0.05), but increased TG, NEFA, glucagon, GLP-1, CCK, leptin, ApoA-IV, serotonin and MSH concentration in blood, the CCK concentration and feed intake showed a significant negative correlation (p < 0.05).

To study the effects of acute hypoxia and intermittent hypoxic acclimatization on cardiac systolic and diastolic functions in rats.Cardiac functions were investigated after intermittent hypoxic acclimatizated (3000 m and 5000 m, 2 wk respectively, 4 h/d) and normoxic rats were exposed to hypoxia (8000 m) for 4 h.The systolic functional parameters such as LVSP, +dp/dtmax, Vpm, Vmax and the diastolic functional parameter -dp/dtmax of acute hypoxic rats were reduced significantly as compared with normoxic control rats. After hypoxic acclimatization, the left ventricular functions of rats were increased significantly as compared with those of acute hypoxic rats. But they were still lower than those of normoxic control rats.Acute hypoxia can affect cardiac functions and hypoxic acclimatization can alleviate the hypoxic effects on cardiac functions.

To observe the preventive and therapeutic effects of gangliosides on acute altitude hypoxic brain damage.Fifteen Wistar rats, weighed 180-220 g, were randomly divided into 3 groups, hypoxia group A, hypoxia group B and normoxia group. The rats in hypoxia group A were exposed to a simulated altitude of 7000 m for 5 hours and the rats in hypoxia group B were exposed to hypoxia after intraperitoneal administration of mixed gangliosides (100 mg/kg/d) for 3 days.Gangliosides could ameliorate the severity of damage in neuronal bodies, cellular skeletons and synapses, especially in synapses.It is suggested that gangliosides are effective in preventing and treating hypoxic brain damages by decreasing the accumulation of intracellular Ca2+, and stabilizing CaM and CaM PKII activity during acute hypoxia.

To correlate the injury of vascular endothelial cells during various pathological conditions with the change of vWF (von Willebrand Factor) in different VEC lines.Flow cytometer(FCM) were used to defect the immunoflourescent stained vWF in pulmonary artery endothelial cells (PAEC) of pig and aortic endothelial cells(AEC) of rats.The positive rates of vWF in PAEC of pigs is similar with that in AEC of rats under normal condition, but it decreased differently after hypoxic or cold injury. It was very interesting that the mean fluorescence intensity of positive PAEC or AEC exposed to hypoxia or cold elevated significantly compared with those of control.The change of vWF in VEC can be used to evaluate the function of VEC under different stress.