健康汉族人细胞色素P450 2C19基因的检测

目的：了解广东地区汉族人细胞色素（P450 2C19）基因的分布情况。方法：应用PCR技术对正常人细胞色素（P450 2C19）基因进行扩增以SmaI进行限制性酶切图谱分析。结果：广东地区汉族人P450 2C19基因中，野生型纯合子（wt/wt）频率是0.4454；CYP2C19杂合子（mt/ml）频率是0.4091；CYP2C19突变型纯合子（ml/ml）频率是0.1455。P450 2C19基因ml频率是0.3500，基因wt频率是0.6500。结论：广东地区汉族人的细胞色素CYP2C19基因频率与其它地区人群相接近。     

COX-2和P53在炎症应激和肿瘤发生中相互作用的研究进展

COX-2在多种肿瘤组织中过量表达,COX-2活性和前列腺素合成的增加促进细胞增殖、血管新生、肿瘤细胞浸润及抑制细胞凋亡.许多应激和前炎症信号,如氧自由基和DNA损伤剂,可诱导COX-2和P53的表达,而P53作为一种转录因子在肿瘤中常因突变而失活.已有研究表明,P53和COX-2存在复杂的交叉作用,P53能上调或下调COX-2的表达,而COX-2也可以调控p53转录活性,但两者相互作用的分子依据一直存在着争论.本文综述了炎症应激和肿瘤发生中COX-2和P53相互作用及其机制的研究进展.     

P57kip2蛋白表达与水泡状胎块分型的关系

目的探讨P57kip2蛋白在水泡状胎块分型诊断中的作用。方法完全性和部分性水泡状胎块分别为78和42例,应用免疫组织化学SP法检测其P57kip2蛋白表达情况。结果P57kip2蛋白在完全性水泡状胎块中表达主要呈弱阳性,在部分性水泡状胎块中以强阳性为主,在部分性水泡状胎块中的阳性率为(92.86%),显著高于完全性水泡状胎块(P<0.01)。结论检测水泡状胎块中P57kip2蛋白表达,有助于水泡状胎块的分型和判断预后。     

COX-2和P53在炎症应激和肿瘤发生中相互作用的研究进展

COX-2在多种肿瘤组织中过量表达,COX-2活性和前列腺素合成的增加促进细胞增殖、血管新生、肿瘤细胞浸润及抑制细胞凋亡.许多应激和前炎症信号,如氧自由基和DNA损伤剂,可诱导COX-2和P53的表达,而P53作为一种转录因子在肿瘤中常因突变而失活.已有研究表明,P53和COX-2存在复杂的交叉作用,P53能上调或下调COX-2的表达,而COX-2也可以调控p53转录活性,但两者相互作用的分子依据一直存在着争论.本文综述了炎症应激和肿瘤发生中COX-2和P53相互作用及其机制的研究进展.     

Role of P2X and P2Y receptors in rat myocardial contractility during ontogeny

Stable agonist of P2 receptors 2-methylthio-ATP and selective antagonists of P2X and P2Y receptors PPADS and reactive blue-2 were used for evaluation of the role of P2 receptors in positive contractile reaction of atrial and ventricular myocardium in rats. PPADS significantly moderated the effects of 2-methylthio-ATP in 14-, 21-, and 56-day-old rat pups, but potentiated them in 100-day-old rats. Under conditions of reactive blue-2 treatment, the positive effect of the agonist was preserved in the atria and ventricles in all age groups and was age-dependent. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 143, No. 6, pp. 637–640, June, 2007     

Impairment of the splenic immune system in P2X(2)/P2X(3) knockout mice

The isolated spleens from male and female mice lacking P2X(2) and P2X(3) receptors (P2X(2)/P2X(3) knockout (KO) mice) and those from wild-type (WT) mice were investigated by flow cytometry, immunohistochemistry and functionally by organ-bath pharmacology. The spleens from the P2X(2)/P2X(3) KO mice weighed significantly more than the corresponding WT mice. Flow cytometry was used to isolate the mononuclear cells, which were then phenotyped. T-lymphocytes, B-lymphocytes and macrophages were identified and counted. It was found that the increase in size of the spleens from the KO animals corresponded to an increase in the numbers of mononuclear cells present and that all three cell types (T-lymphocytes, B-lymphocytes and macrophages) increased in much the same proportion as those from the WT animals. Immunohistochemical localisation of P2Y(1), P2Y(2) and P2X(1) receptors revealed their presence on the spleen capsule and trabeculae. P2X(1) receptors were also present on blood vessels. There was no difference in the expression of these receptors between the WT and P2X(2)/P2X(3) KO spleens. Functional studies revealed the presence of multiple P2 receptors inducing the contraction of the spleen capsule, from both WT and KO mice. There was no difference in the contractions induced by adenosine 5'-triphosphate (ATP), alpha,beta-methylene ATP, 2-methylthio ADP or uridine triphosphate from WT and KO mice. It is concluded that mice lacking both P2X(2) and P2X(3) receptors have enlarged spleens and that this is correlated with an increase in the number of immune cells, perhaps as a consequence of a compromised immune system and chronic infection.     

Identification of RNA-binding regions on the P and V proteins of human parainfluenza virus type 2

We have shown that the P and V proteins of human parainfluenza virus type 2 (hPIV-2) bind to genomic RNA by using Northwestern blot analysis. To identify the RNA-binding regions on the P and V proteins, we used a set of deletion mutants produced in Escherichia coli. One region required for the RNA-binding was found in the P–V common domain (aa 1–82). Others were found in the P protein-specific region (aa 249–354) and the V protein-specific region (aa 176–225). In addition, we have shown that substitutions of some basic residues with alanines in these regions abrogate RNA-binding by the P or V proteins. Intriguingly, the P and V proteins of hPIV2 can selectively bind to the viral RNA under our experimental conditions.     

MDM2和P53蛋白表达与原发性肝细胞肝癌发生的关系

目的:研究MDM2和突变型P53蛋白表达与原发性肝细胞肝癌(HCC)发生的关系。方法: 用免疫组织化学SP法,检测55例HCC癌组织、23例癌旁组织、10例正常肝组织MDM2和突变型P53蛋白表达情况。结果: 55例HCC中MDM2蛋白阳性表达17例(30.9%),突变型P53蛋白阳性表达23例(41.8%),二者均阳性表达11例(20%),MDM2和突变型P53蛋白表达有相关性(r=0.310, P＜0.05)。23例癌旁组织MDM2蛋白阳性1例,突变型P53蛋白阳性表达2例,肝癌组织和癌旁组织MDM2和突变型P53蛋白表达有差异(P＜0.05)。10例正常肝组织无MDM2和突变型P53蛋白表达。结论: 肝细胞癌组织有MDM2和突变型P53过量表达,MDM2蛋白和/或 p53 基因突变使 p53 基因功能失活在HCC发生中可能有重要作用。     

Increase of intracellular Ca by P2X and P2Y receptor-subtypes in cultured cortical astroglia of the rat

Astrocytes express purinergic receptors that are involved in glial–neuronal cell communication. Experiments were conducted to characterize the expression of functional P2X/P2Y nucleotide receptors in glial cells of mixed cortical cell cultures of the rat. The vast majority of these cells was immunopositive for glial fibrillary acidic protein (GFAP) and was considered therefore astrocyte-like; for the sake of simplicity they were termed “astroglia” throughout. Astroglia expressed predominantly P2X_4,6,7 as well as P2Y_1,2 receptor-subtypes. Less intensive immunostaining was also found for P2X₅ and P2Y_4,6,13,14 receptors. Pressure application of ATP and a range of agonists selective for certain P2X or P2Y receptor-subtypes caused a concentration-dependent increase of intracellular Ca²⁺ ([Ca²⁺]_i). Of the agonists tested, only the P2X_1,3 receptor-selective α,β-methylene ATP was ineffective. Experiments with Ca²⁺-free solution and cyclopiazonic acid, an inhibitor of the endoplasmic Ca²⁺-ATPase, indicated that the [Ca²⁺]_i response to most nucleotides, except for ATP and 2′,3′-O-(benzoyl-4-benzoyl)-ATP, was due primarily to the release of Ca²⁺ from intracellular stores. A Gprotein–mediated release of Ca²⁺ is the typical signaling mechanism of various P2Y receptor-subtypes, whose presence was confirmed also by cross-desensitization experiments and by using selective antagonists. Thus, our results provide direct evidence that astroglia in mixed cortical cell cultures express functional P2Y (P2Y_1,2,6,14 and probably also P2Y₄) receptors. Several unidentified P2X receptors, including P2X₇, may also be present, although they appear to only moderately participate in the regulation of [Ca²⁺]_i. The rise of [Ca²⁺]_i is due in this case to the transmembrane flux of Ca²⁺ via the P2X receptor-channel. In conclusion, P2Y rather than P2X receptor-subtypes are involved in modulating [Ca²⁺]_i of cultured astroglia and thereby may play an important role in cell-to-cell signaling.     

LPS对大鼠海马CA2～3区nNOS和FOS蛋白表达的影响

目的 探讨NO和c-fos在SD大鼠海马CA2～3区免疫调节中的作用。方法 腹腔注射LPS600μg／kg建立免疫激发模型，对照组注射等量的生理盐水，用免疫组化方法和图像分析技术，观察两组大鼠海马CA2～3区nNOS和FOS蛋白的表达，检测OD值并进行统计学分析。结果 nNOS和FOS蛋白在大鼠海马各区均有散在分布，LPS刺激组海马CA2～3区nNOS和c-fos免疫阳性产物的OD值较对照组高，差异具有统计学意义。结论海马CA2～3区可能通过NO和(或)c-fos途径参与调节LPS诱导的免疫反应过程。