产前应用地塞米松对早产仔鼠脑发育的影响

Objective To explore the effects of different courses of antenatal dexamethasone on brain development of premature SD rats. Methods The pregnant rats were randomly assigned to 3 groups: 3-dose dexamethasone (group 1), 1-dose dexamethasone group (group 2) and control group. The treated were sacrificed on 19 days of gestation, body and whole brain weight of the offspring rats were measured. Meanwhile the expression o{ neuron specific enolase (NSE) in brains of offspring rats was detected by immunohistochemical staining. The histological structures of baby rat brain were observed under transmission electron microscope. The differences among the three groups were analyzed by ANOVA. Results (1) The body and whole brain weight, the brain and body weight ratio were (1.543±0.052) g, (88.80±7.12) mg, and (5.75±0.38)% in group 1 and (1.584±0.035) g,(98.21±3.71) mg, and (6.20±0.26)% in group 2, both were lower than the control group [(1.696±0.076) g, (111.53±6.29) mg, (6.59±0.48)%], (P<0.01 or P<0.05, respectively). (2) The expression of NSE in cortex in group 1 and 2 were lower than that in control group (0.223±0.054, 0.381±0.041 vs 0.590±0.064) (P<0.01). The expression of NSE in hippocampi in group 1 and 2 were also lower than that in the control group (0.192±0.054, 0.359 ±0.046 vs 0.529±0.068) (P<0.01). (3) Disconnection of nuclei membrane, vacuolization in mitochondria, loss of nueleolus, and disconnection of neurofilaments were observed in the ultrastructure of baby rat brain tissue in both group 1 and 2. Conclusions Antenantal administration of dexamethasone can cause impairment of brain development in premature offspring rats and this might be related to the times of dexamethasone administered.     

水通道蛋白1和水通道蛋白3在羊水过少孕妇胎盘和胎膜的表达及其意义

Objective To study the expression of aquaporin 1 (AQP1) and aquaporin 3 (AQP3) in fetal membranes and placenta in pregnant women with oligohydramnios and to explore their function in the balance of amniotic fluid. Methods Thirty cases of term pregnancy with oligohydramnios were selected as the experimental group and 30 healthy term pregnant women with normal amniotic fluid volume were served as control. The expressions of mRNA and protein of AQP1 and AQP3 in fetal membranes and placenta were examined by real-time polymerase chain reaction and streptavidi peroxidase immunohistochemiscal staining. Results The expression of AQP1 mRNA in the amnion of the experimental group was 0.31 relative to that of the control group. The expression of AQP1 protein in the amnion of the experimental group was 0.14±0.02, which showed significant decrease when compared with the control (0.25±0.03) (P<0.05), while no significant difference in the chorion and placenta was found between the two groups(P>0.05). The amount of AQP3 mRNA expressions in amnion and chorion in the experimental group were 0.31 and 0.37 relative to those of the control group, respectively, while 7.36 in the placenta. The expression of the AQP3 protein in the amnion and chorion in the experimental group were 0.18±0.05 and 0.18±0.04, respectively, which showed significant decrease when compared with those in the control group (0. 26±0.03 vs 0.29± 0.06, P<0.05). But the expression of AQP3 protein in the placenta of experimental group was significantly higher than that of the control (0.47±0.09 vs 0.28±0.01, P<0.05). Conclusions The alterations of AQP1 and AQP3 expressions in fetal membrane and placenta in oligohydramniotic women are adaptive response to oligohydramnios.     

子宫平滑肌组织中RhoA及Rho激酶的表达与分娩发动的关系

Objective To investigate the role of RhoA and Rho kinase system in the onset of labor. Methods Forty term pregnant women, who delivered through cesarean section at the Xiangya Second Hospital of Central South University from February 2007 to November 2007, were selected and divided into 2 groups: 20 in labor group and 20 in non-labor group. Another 20 non-pregnant women undergoing hysterectomy due to cervical intraepithelial neoplasia were chosen as the control. Real-time fluorescence quantitative RT-PCR and western blot were applied to detect the expression RhoA and ROCKⅠ mRNA and protein in uterine smooth muscle tissue and the correlation between the mRNA and protein expression of RhoA and ROCKⅠ were analyzed. Results (1) The mRNA expressions of both RhoA and ROCKⅠ were detected in all groups, and higher levels were found in the labor group than in the non-labor group and the control [RhoA mRNA: (3.51±0.56)×10-3 vs. (2.75±0.52)×10-3 and (2.11±0.54)×10-3; ROCKⅠ mRNA: (4.07±0.66)×10-3 vs. (2.71±0.52)×10-3 and(2.01±0.23)×10-3, P<0.01]. (2) RhoA and ROCKⅠ proteins were also identified in all three groups, and the expressions in the labor and non-labor group were higher than those of the control (RhoA protein: 0.72±0.23 and 0.64±0.17 vs. 0.46±0.15; ROCKⅠ protein: 0.56±0.14 and 0.42±0.16 vs. 0.29±0.08, P<0.01). (3) The expression of RhoA mRNA and ROCKⅠ mRNA were positively correlated in each of the three groups (r=0.73,P<0.01), and the same was found in the expression of RhoA protein and ROCKⅠ protein (r=0.37,P<0.01). Conclusion The increased expression of RhoA and Rho kinase may play an important role in the initiation of labor.     

子宫平滑肌组织中RhoA及Rho激酶的表达与分娩发动的关系

Objective To investigate the role of RhoA and Rho kinase system in the onset of labor. Methods Forty term pregnant women, who delivered through cesarean section at the Xiangya Second Hospital of Central South University from February 2007 to November 2007, were selected and divided into 2 groups: 20 in labor group and 20 in non-labor group. Another 20 non-pregnant women undergoing hysterectomy due to cervical intraepithelial neoplasia were chosen as the control. Real-time fluorescence quantitative RT-PCR and western blot were applied to detect the expression RhoA and ROCKⅠ mRNA and protein in uterine smooth muscle tissue and the correlation between the mRNA and protein expression of RhoA and ROCKⅠ were analyzed. Results (1) The mRNA expressions of both RhoA and ROCKⅠ were detected in all groups, and higher levels were found in the labor group than in the non-labor group and the control [RhoA mRNA: (3.51±0.56)×10-3 vs. (2.75±0.52)×10-3 and (2.11±0.54)×10-3; ROCKⅠ mRNA: (4.07±0.66)×10-3 vs. (2.71±0.52)×10-3 and(2.01±0.23)×10-3, P<0.01]. (2) RhoA and ROCKⅠ proteins were also identified in all three groups, and the expressions in the labor and non-labor group were higher than those of the control (RhoA protein: 0.72±0.23 and 0.64±0.17 vs. 0.46±0.15; ROCKⅠ protein: 0.56±0.14 and 0.42±0.16 vs. 0.29±0.08, P<0.01). (3) The expression of RhoA mRNA and ROCKⅠ mRNA were positively correlated in each of the three groups (r=0.73,P<0.01), and the same was found in the expression of RhoA protein and ROCKⅠ protein (r=0.37,P<0.01). Conclusion The increased expression of RhoA and Rho kinase may play an important role in the initiation of labor.     

子宫平滑肌组织中RhoA及Rho激酶的表达与分娩发动的关系

Objective To investigate the role of RhoA and Rho kinase system in the onset of labor. Methods Forty term pregnant women, who delivered through cesarean section at the Xiangya Second Hospital of Central South University from February 2007 to November 2007, were selected and divided into 2 groups: 20 in labor group and 20 in non-labor group. Another 20 non-pregnant women undergoing hysterectomy due to cervical intraepithelial neoplasia were chosen as the control. Real-time fluorescence quantitative RT-PCR and western blot were applied to detect the expression RhoA and ROCKⅠ mRNA and protein in uterine smooth muscle tissue and the correlation between the mRNA and protein expression of RhoA and ROCKⅠ were analyzed. Results (1) The mRNA expressions of both RhoA and ROCKⅠ were detected in all groups, and higher levels were found in the labor group than in the non-labor group and the control [RhoA mRNA: (3.51±0.56)×10-3 vs. (2.75±0.52)×10-3 and (2.11±0.54)×10-3; ROCKⅠ mRNA: (4.07±0.66)×10-3 vs. (2.71±0.52)×10-3 and(2.01±0.23)×10-3, P<0.01]. (2) RhoA and ROCKⅠ proteins were also identified in all three groups, and the expressions in the labor and non-labor group were higher than those of the control (RhoA protein: 0.72±0.23 and 0.64±0.17 vs. 0.46±0.15; ROCKⅠ protein: 0.56±0.14 and 0.42±0.16 vs. 0.29±0.08, P<0.01). (3) The expression of RhoA mRNA and ROCKⅠ mRNA were positively correlated in each of the three groups (r=0.73,P<0.01), and the same was found in the expression of RhoA protein and ROCKⅠ protein (r=0.37,P<0.01). Conclusion The increased expression of RhoA and Rho kinase may play an important role in the initiation of labor.     

子宫平滑肌组织中RhoA及Rho激酶的表达与分娩发动的关系

Objective To investigate the role of RhoA and Rho kinase system in the onset of labor. Methods Forty term pregnant women, who delivered through cesarean section at the Xiangya Second Hospital of Central South University from February 2007 to November 2007, were selected and divided into 2 groups: 20 in labor group and 20 in non-labor group. Another 20 non-pregnant women undergoing hysterectomy due to cervical intraepithelial neoplasia were chosen as the control. Real-time fluorescence quantitative RT-PCR and western blot were applied to detect the expression RhoA and ROCKⅠ mRNA and protein in uterine smooth muscle tissue and the correlation between the mRNA and protein expression of RhoA and ROCKⅠ were analyzed. Results (1) The mRNA expressions of both RhoA and ROCKⅠ were detected in all groups, and higher levels were found in the labor group than in the non-labor group and the control [RhoA mRNA: (3.51±0.56)×10-3 vs. (2.75±0.52)×10-3 and (2.11±0.54)×10-3; ROCKⅠ mRNA: (4.07±0.66)×10-3 vs. (2.71±0.52)×10-3 and(2.01±0.23)×10-3, P<0.01]. (2) RhoA and ROCKⅠ proteins were also identified in all three groups, and the expressions in the labor and non-labor group were higher than those of the control (RhoA protein: 0.72±0.23 and 0.64±0.17 vs. 0.46±0.15; ROCKⅠ protein: 0.56±0.14 and 0.42±0.16 vs. 0.29±0.08, P<0.01). (3) The expression of RhoA mRNA and ROCKⅠ mRNA were positively correlated in each of the three groups (r=0.73,P<0.01), and the same was found in the expression of RhoA protein and ROCKⅠ protein (r=0.37,P<0.01). Conclusion The increased expression of RhoA and Rho kinase may play an important role in the initiation of labor.     

Effect of lubrication of frictional properties of sutures

The results of this study have provided an insight into the behavior of sutures in the environment of fluids. It has been shown that friction could both increase or decrease with lubrication, depending upon the nature of the application. In tests on straight sutures, lubricants have generally led to an increase in friction. This was found in the present investigation as well as in another study which measured friction in sutures soaked in serum. These results are explained on the basis that higher friction is expected to arise if the lubricant formed a multilayer film between the sliding surfaces. In this instance, the resistance to shear flow by the lubricant becomes the governing factor. On the other hand, if only a small amount of lubricant, such as a monolayer film, is present between surfaces, as expected within the structure of a snugged surgical knot, the lubricant may play the role of decreasing adhesion and, thus, friction.