A new method for noninvasive prenatal diagnosis of fetal sex was developed by using single-cell PEP-PCR techniques. Micromamipulation techniques were used to obtain single fetal cells from 273 maternal blood samples. The genome of single cells was preamplified by PEP and SRY genes were analyzed by PCR method. The SRY genes of 149 samples were detected by the new method among 153 samples carrying male fetus, while 119 out of 120 samples carrying female fetus were proved negative for SRY genes. The sensitivity and specificity of the new method were 97.39% and 99.17% respectively and the correct rate was 98.17%. The new method has the advantage of high sensitivity and specificity in noninvasive prenatal diagnosis of fetal sex and provides the basis of other researches such as sex-linked inherited diseases.
In order to explore whether the member of Bcl-2 gene family, for example, Bcl-2 and Bax, are induced after cerebral ischemia, and whether expression of genes can be modulated by calcium-antagonist, the rat cerebral ischemic models were made by occluding left middle cerebral artery. The expression of Bcl-2 and Bax mRNA was measured by RT-PCR method. After middle cerebral artery occlusion (MCAO), the expression of both Bcl-2 and Bax mRNA were induced. Level of Bcl-2 mRNA increased steadily and level of Bax mRNA increased gradually at first, reached a peak after 24 h, then decreased slowly. After administration of nimodipine, Bcl-2 mRNA was up-regulated in the hippocampus 6 and 24h after ischemia, while Bax mRNA was down-regulated 6 and 24 h after ischemia. Focal cerebral ischemia can induce proto-oncogenes to express, which was associated with apoptosis. Calcium-antagonist can up-regulate Bcl-2 mRNA and down-regulate Bax mRNA. The increased ratio of Bcl-2 and Bax mRNA may contribute to the anti-apoptic effect of nimodipine. The study indicates that pharmacological modulation of Bcl-2 family member expression could become a new strategy to manage neuronal damage.
In order to study whether marrow stromal cells (MSCs) can be induced into nerve-like cellsin vitro, and the mechanism, the MSCs in Wistar rats were isolated and cultured, and then induced with DMSO and BHAin vitro. The expression of specific marking proteins in neurons, glia and neural stem cells were detected before preinduction, at 24 h of preinduction, at 6 h, 24 h, and 48 h of neuronal induction by using immunohistochemistry and Western blotting. The ultrastructural changes after the inducement were observed. The results showed that after the inducement, many MSCs turned into bipolar, multipolar and taper, and then intersected as network structure. At the same time, some MSCs had the typical neuron-like ultrastructure. Immunohistochemistry revealed that NeuN and Nestin expression was detectable after inducement, but there was no GFAP and CNP expression. Western blotting showed the expression of Nestin was strong at 6 h of neuronal induction, and decreased at 24 h, 48 h of the induction. NeuN was detectable at 6 h of neuronal induction, and increased at 24 h, 48 h of the induction. It was concluded MSCs were induced into neural stem cells, and then differentiated into neuron-like cellsin vitro.
In this study, whole cell patch clamp recording technique was employed to investigate the effect of Shenmai Injection (SMI) on L-type calcium current of diaphragmatic muscle in rats. The result showed that when the diaphragmatic muscle cell was held at −80 mV and depolarized to +60 mV, 10 μl/ml, 50 μl/ml and 100 μl/ml SMI enhanced the inner peak L-type calcium current from −(6.8±0.7) pA/pF (n=7) to −(7.3±0.8) pA/pF (P>0.05,n=7), −(8.6±1.0) pA/pF (P<0.05,n=7) and −(9.4±1.2) pA/pF (P<0.05,n=7), respectively. The rates of L-type calcium current were increased by (7.34±2.37) %, (25.72±5.94) %, and (38.16±7.33)%, respectively. However, it had no significant effect on maximal activation potential and reversal potential. Our results suggested that SMI could activate the calcium channel of the diaphragmatic fibers of the rats, increase the influx of Ca2+, and enhance the contractility of diaphragmatic muscles.
The activity of the NK cells in patients with preeclampsia was studied to investigate the pathogenesis of preeclampsia. By using MTT and21Cr releasing technique, the proliferation and killing ability of the NK cells in maternal and umbilical blood from preeclampsia patients (n=18) and normal third trimester pregnant women (n=18) were detected. The NK-92 cell line was as the positive control. The results showed that the NK cell counts of umbilical blood in preeclampsia patients and normal third trimester pregnant women were significantly greater than those of maternal blood (bothP<0.05). Compared with that in normal third trimester pregnant women, the proliferative ability of the NK cells in, preeclampsia patients was apparently increased (P<0.05). Compared with that in maternal blood, the proliferative ability of the NK cells in umbilical blood from both preeclampsia patients and normal third trimester pregnant women was dramatically increased. The killing ability of the NK cells in preeclampsia patients was significantly higher than that in normal third trimester pregnant women (P<0.05). It was suggested that both number and function of the NK cells in preeclampsia women were increased, and that in umbilical blood was greater than that in maternal blood, speculating that the function of the NK cells may affect the maintenance of the maternal and fetal immune tolerance during pregnancy.