Effects of over-expressing resistin on glucose and lipid metabolism in mice

Resistin, a newly discovered peptide hormone mainly secreted by adipose tissues, is present at high levels in serum of obese mice and may be a potential link between obesity and insulin resistance in rodents. However, some studies of rat and mouse models have associated insulin resistance and obesity with decreased resistin expression. In humans, no relationship between resistin level and insulin resistance or adiposity was observed. This suggests that additional studies are necessary to determine the specific role of resistin in the regulation of energy metabolism and adipogenesis. In the present study, we investigated the effect of resistin in vivo on glucose and lipid metabolism by over-expressing resistin in mice by intramuscular injection of a recombinant eukaryotic expression vector pcDNA3.1-Retn encoding porcine resistin gene. After injection, serum resistin and serum glucose (GLU) levels were significantly increased in the pcDNA3.1-Retn-treated mice; there was an obvious difference in total cholesterol (TC) level between the experiment and the control groups on Day 30. In pcDNA3.1-Retn-treated mice, both free fatty acid (FFA) and high density lipoprotein (HDL) cholesterol levels were markedly lower than those of control, whereas HDL cholesterol and triglyceride (TG) levels did not differ between the two groups. Furthermore, lipase activity was expressly lower on Day 20. Our data suggest that resistin over-expressed in mice might be responsible for insulin resistance and parameters related to glucose and lipid metabolism were changed accordingly.     

The relations of parenting,effortful control,and ego control to children's emotional expressivity

The relations of observed parental warmth and positive expressivity and children's effortful control and ego control with children's high versus low emotional expressivity were examined in a 2-wave study of 180 children (M age = 112.8 months). There were quadratic relations between adults' reports of children's emotional expressivity and effortful control; moderate expressivity was associated with high effortful control. Structural equation models supported the hypothesis that children's ego overcontrol (versus undercontrol) mediated the relation between parental warmth or positive expressivity and children's emotional expressivity, although parenting at the follow-up did not uniquely predict in children's expressivity after controlling for the relations in these constructs over time. The alternative hypothesis that children's ego overcontrol elicited positive parenting and expressivity also was supported.     

Early maternal and child influences on children's later independent cognitive and social functioning

The present study examined whether parenting and child characteristics of 2- and 3 1/2-year-old children had common paths of influence on their 4 1/2-year independent cognitive and social functioning. Structural equation modeling was guided by hypotheses that assumed children's later independence is facilitated by specialized parental support in early social interactions. To address the importance of variability in early development for understanding children's later independence, we included 104 term and 185 preterm children, as they are known to differ in early skills. As predicted, mothers' maintaining of children's interests indirectly supported 4 1/2-year cognitive and social independence through a direct, positive influence on 2- and 3 1/2-year skills. Directiveness positively supported children's early cognitive and responsiveness skills but by 3 1/2 years, high levels of this behavior had a direct, negative influence on their cognitive and social independence at 4 1/2 years. Whereas high levels of maintaining interests across these ages support later independence, directiveness needs to decrease in relation to children's increasing competencies. Results support a theoretical framework that emphasizes the importance of the social context for understanding the origins of children's later independent functioning.     

Isolation and physiological characteristics of a premature senescence mutant in rice （Oryza sativa L.）

A rice pse(t) (premature senescence, tentatively) mutant line, was isolated from 4500 independent T-DNA inserted transgenic lines. The symptoms of premature senescence appeared more severely than those of the control plants (Zhonghua 11,japonica) at the last development stage. To characterize the mutant and provide basic information on the candidate genes by mapping to a physical region of 220-kb, experiments were carried out in two phytotrons under controlled temperature of 24 ℃ and28 ℃, respectively. The content of chlorophyll, soluble protein and MDA (malondialdehyde), net photosynthesis, the antioxidant enzyme activities of SOD (superoxide dismuase) (EC 1.15.1.1) and POD (peroxidase) (EC 1.11.1.7) and the peptidase activities of leaves were measured from top to bottom according to the leaf positions at the flowering stage. Compared with the control plant,the mutant showed the following characteristics: (1) Higher net photosynthesis rate (Pn) appeared in the 1 st and 2nd leaves, contents of chlorophyll and soluble protein were also higher in the 1 st leaf; (2) The activities of SOD, POD and peptidase were higher according to the leaf position from top to bottom; (3) The symptom of premature senescence was accelerated in the mutant at 28℃treatment. The MDA content and the SOD and POD activities between the 24 ℃ and 28 ℃ treatment mutants were not significantly different. Content of chlorophyll and soluble protein of leaves mutant decreased rapidly at 28 ℃ treatment. The results show that pse(t) is sensitive to high temperature. The probable function of PSE(T) is discussed.     

Increased expression of aquaporin-4 in human traumatic brain injury and brain tumors

Objective:To characterize the expression of aquaporin-4(AQP4),one of the aquaporins(AQPs),in human brainspecimens from patients with traumatic brain injury or brain tumors.Methods:Nineteen hnman brain specimens were obtahledfrom the patients with traumatic brain injury,brain tumors,benign meningioma or early stage hemorrhagic stroke.MRI or CTimaging was used to assess brain edema.Hematoxylin and eosm staining were used to evaluate cell damage,Immunohistochem-istry was used to detect the AQP4 expression.Results:AQP4 expression was increased from 15 h to at least 8 d after injury.AQP4immunoreactivity was strong around astrocytomas,ganglioglioma and metastatic adenocarcinoma.However,AQP4 immunore-activity was only found in the centers of astrocytomas and ganglioglioma,but not in metastatic adenocarcinoma derived from lung.Conclusion:AQP4 expression increases in human brains alter traumatic brain injury,within brain-derived tumors,and aroundbrain tumors.     

The relations of effortful control and impulsivity to children's resiliency and adjustment

The unique relations of effortful control and impulsivity to resiliency and adjustment were examined when children were 4.5 to 8 years old, and 2 years later. Parents and teachers reported on all constructs and children's attentional persistence was observed. In concurrent structural equation models, effortful control and impulsivity uniquely and directly predicted resiliency and externalizing problems and indirectly predicted internalizing problems (through resiliency). Teacher-reported anger moderated the relations of effortful control and impulsivity to externalizing problems. In the longitudinal model, all relations held at T2 except for the path from impulsivity to externalizing problems. Evidence of bidirectional effects also was obtained. The results indicate that effortful control and impulsivity are distinct constructs with some unique prediction of resiliency and adjustment.