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991.
Variations of Ki-67, p53, and Adnab-9 monoclonal antibody reactions in colonic adenomas may be associated with colonic cancer risk. We studied the predictive value of these markers for adverse behavior in severely dysplastic colorectal adenomas, such as an associated carcinoma, multiplicity of adenomas, and subsequent development of adenomas. For this purpose we compared the clinical, gross, and histologic characteristics of highly dysplastic index polyps in 42 patients with Ki 67, p53, and Adnab-9 immunostaining and other molecular markers. Polyps were removed endoscopically, and severely dysplastic polyps were stained immunohistochemically with Ki-67, Adnab-9, and p53 protein by the avidin biotin conjugate (ABC) technique. Quantitative DNA (QDNA) was analyzed by computer-assisted image analysis. Ki-67 immunohistochemistry showed reversal of normal distribution of nuclear staining from the normal basal position to the upper third of the colonic crypts. This abnormality of immunostaining in dysplastic adenomas was the earliest detected by the panel we used. A statistically significant correlation was seen between invasiveness of carcinoma in the index polyp and polyp size (P = 0.003), sessile morphology (P = 0.037), and villous or tubulovillous histology (P = 0.019). In the index adenoma, p53 positivity was correlated with multiplicity at initial examination (P = 0.053), villous histology (P = 0.053), invasiveness of carcinoma (P < 0.003), and recurrence of colorectal adenomas (P = 0.025). Although p53 positivity and aneuploidy were correlated with invasiveness of carcinoma in the index polyp (P = 0.025), Adnab-9 positivity was not. However, Adnab-9 positivity in the index polyp was associated with multiplicity of adenomas (P = 0.04) as well as recurrence of adenomas (P < 0.024). In conclusion, in addition to the morphologic and histologic markers already known, Ki-67, Adnab-9 antibody, and p53 protein may be prognostic indicators useful in follow-up of patients with severely dysplastic colorectal adenomas. Adnab-9 antibody may identify a field defect in above-average-risk adenoma-bearing patients.  相似文献   
992.
On activation platelets release microRNAs and extracellular vesicles (EV) into circulation. The release of EV from platelets has been shown to be dependent on the agonist; in this study, we investigated whether the microRNA profile or EV released from platelets was also agonist specific.

Washed platelets from healthy subjects were maximally stimulated with agonists specific for the receptors for collagen (Glycoprotein VI (GPVI)), thrombin (PAR1/PAR4), or ADP (P2Y1/P2Y12) with/without inhibiting secondary mediators, using aspirin to block cyclooxygenase-1 and apyrase to remove ADP. The released microRNAs were profiled using TaqMan microRNA microarray cards. Platelet-derived EV (pdEV) were characterized by size (Nanoparticle Tracking Analysis, NTA), for procoagulant activity (Annexin-V binding and support of thrombin generation), and for the EV markers CD63 and HSP70.

Platelet activation triggered the release of 57–79 different microRNAs, dependent upon agonist, with a core of 46 microRNAs observed with all agonists. There was a high level of correlation between agonists (r2 > 0.98; p < 0.0001 for all), and with the microRNA content of the parent platelets (r2 > 0.98; p < 0.0001). The 46 microRNAs seen in all samples are predicted to have significant effects on the translation of proteins involved in endocytosis, cell cycle control, and differentiation. MiR-223-3p was the most abundant in all samples and has previously been implicated in myeloid lineage development and demonstrated to have anti-inflammatory effects. Stimulation through GPVI produced a pdEV population with significantly more procoagulant activity than the other agonists. Apyrase significantly reduced microRNA and pdEV release, while aspirin had little effect.

These data suggest that all tested agonists trigger the release of a similar microRNA profile while the procoagulant activity of the pdEV was agonist dependent. ADP was shown to play an important role in the release of both microRNAs and pdEV.  相似文献   

993.
994.
刘涵  周晓燕  路少林 《山东医药》2007,47(22):22-23
目的 探讨p27蛋白在肺腺癌的表达及临床意义.方法 应用免疫组化技术检测44例肺腺癌患者的p27蛋白表达,分析p27蛋白表达与性别、年龄、肿瘤大小、临床分期、分化程度和淋巴结转移以及预后的关系.结果 p27蛋白水平与肺腺癌的分化程度相关,与患者的年龄、性别、肿瘤大小、淋巴结转移、TMN分期无关.p27蛋白低表达者的平均生存期(18.6个月)明显低于p27蛋白高表达者(34.5个月).结论 p27蛋白表达可以作为评价肺腺癌恶性程度和预后的一个重要指标.  相似文献   
995.
p53 point mutations in primary human gastric carcinomas   总被引:12,自引:0,他引:12  
Summary p53 point mutations in primary gastric carcinomas were analyzed by performing cDNA deoxynucleotide sequencing of the gene. Out of 16,9 (56.3%) primary gastric carcinoma cases, including early cancer, showed one or more p53 point mutations in their open-reading frame, and 4 out of 9 cases had a p53 point mutation within highly conserved domains. The characteristics of the p53 mutation spectrum observed in primary tumors were (a) frequent mutation at an A:T pair (50%, 7 out of 14 mutations), (b) high transversion incidence (29%, 4 out of 14 mutations), (c) no transition at CpG, and (d) no G:C to T:A transversion. Our results suggest that p53 mutation is a common event in gastric carcinoma occurring from the early stage of progression with its specific mutation spectrum.Abbreviation PCR-SSCP polymerase chain reaction single-strand conformation polymorphism  相似文献   
996.
AIM To find out the difference of human primary liver carcinogenesis between Han and minority ethnic patients in Xinjiang.METHODS Expression of p53, c-erbB-2, Hrssp21 protein and proliferating cell nuclear antigen (PCNA) in tumor tissues of 50 patients (Han 38, minority 12 ) with primary hepatic carcinoma was detected by immunohistochemistry (LSAB). RESULTS The positive frequency of p53, cerbB-2, H-rasp21 and PCNA expression was 46.0% (23/50), 70.0% (35/50), 68.0% (34/50)and 82.0% (41/50) in tumor tissues; 4.0% (2/50), 22.0% (11/50), 64.0% (32/50) and 52.0%(26/ 50 ) in peritumors respectively and a significant difference, except for H-rasp21, of oncogene alteration was found (P<0.05)between tumor and non- tumorous tissues.Combined the three oncogenes alteration, 26%(13/50)tumor tissues had positive immunoreactivity, but in peritumor and normal livers it was negative. The positive rate of p53,c-erbB-2 and H-rasp21 protein expression was 39.5% (15/38), 60.5% (23/38) and 39.5% (15/38) in tumors of Han patients; 66.7% (8/12),100% (12/12) and 75.0% (9/12) in minorities respectively, with statistical difference (P<0.05). CONCLUSION Overexpression of p53, c-erbB-2 and H-rasp21 in human primary liver carcinoma is an important biomarker of genetic alteration.The different frequency of these oncogenetic changes may reflect some environmental or/and ethnic hereditary factors affecting the liver carcinogenesis. The special life style of Han,Uygur, Kazak and Mongolia nationalities in Xinjiang may also be related to the etiopathogenesis of this disease.  相似文献   
997.
The p8 gene is barely expressed in the normal pancreas, but is overexpressed in acute pancreatitis. To elucidate the dynamic expression of p8 mRNA and its significance in the course of chronic pancreatitis, we investigated the p8 expression in spontaneous chronic pancreatitis in the WBN/Kob rat as well as in humans and arginine-treated rat pancreatic acinar AR4-2J cells. p8 mRNA was significantly increased at 12 weeks when chronic pancreatitis first appeared in the WBN/Kob rats. p8 was immunolocalized in the acinar cell nuclei. Acinar cell apoptosis was significantly increased at 12 and 20 weeks in the WBN/Kob rats. In AR4-2J cells, p8 mRNA was significantly induced at 4 hr after arginine addition. Apoptosis of AR4-2J cells was not increased during the strong expression of p8 mRNA. These results suggest that p8 is induced in the acinar cells during chronic pancreatitis as the self-defence mechanism against proapoptotic insults.  相似文献   
998.
目的研究p38丝裂原活化蛋白激酶(p38MAPK)信号途径在甲状旁腺素相关肽(PTHrP)诱导的破骨细胞生成和骨吸收中的作用。方法取小鼠骨髓细胞,在PTHrP(45ng/ml)的刺激下,在不同试验组中分别入0.1、1.0及10μmol/L的p38MAPK抑制剂Fr167653,继续培养6d。抗酒石酸染色,进行破骨细胞计数。在小鼠颅骨部位注射PTHrP建立骨吸收和高钙血症动物模型。每日给予p38MAPK抑制剂Fr16765330mg/kg,每日2次,X线片观察骨吸收面积,组织学检查计算单位面积内破骨细胞数目,采集血样观察全血内游离钙水平。结果PTHrP刺激下,大量破骨细胞生成(118.9±28.3)个/孔;加入0.1μmol/LFr167653可以部分抑制破骨细胞的生成(79.6±28.0)个/孔,加入10μmol/LFr167653几乎全抑制了破骨细胞生成(7.4±0.4)个/孔,每日给予Fr16765330mg/kg,每日2次,可以明显抑制骨吸收,表现为X线片上骨吸收面积减少,单位面积内破骨细胞数目减少,但是并不能有效地抑制高钙血症。结论抑制p38MAPK信号途径可以抑制破骨细胞的分化和局部骨吸收。  相似文献   
999.
1000.
AIM: To investigate the prevalence of the ATP7B gene mutation in patients with hepatic presentation of Wilson's disease (WD) in Lithuania. METHODS: Eleven unrelated Lithuanian families, including 13 WD patients were tested. Clinically WD diagnosis was established in accordance to the Leipzig scoring system. Genomic DNA was extracted from whole venous blood using a salt precipitation method. Firstly, the semi-nested polymerase chain reaction (PCR) technique was used to detect the c.3207C〉A (p.H1069Q) mutation. Patients not homozygous for the c.3207C〉A (p.H1069Q) mutation were further analyzed. The 21 exons of the WD gene were amplified in a thermal cycler (Biometra T3 Thermocycler, G0ttingen, Germany). Direct sequencing of the amplified PCR products was performed by cycle sequencing using fluorescent dye terminators in an automatic sequencer (Applied Biosystems, Darmstadt, Germany). RESULTS: Total of 13 WD patients (mean age 26.4 years; range 17-40; male/female 3/10) presented with hepatic disorders and 16 their first degree relatives (including 12 siblings) were studied. Some of WD patients, in addition to hepatic symptoms, have had extrahepatic disorders (hemolytic anemia 3; Fanconi syndrome 1; neurophsychiatric and behavioural disorder 2). Liver biopsy specimens were available in all of 13 WD patients (8 had cirrhosis; 1-chronic hepatitis; 3-acute liver failure, 1-1iver steatosis). Twelve of 13 (92.3%) WD patients had the c.3207C〉A (p.HI069Q) mutation, 6 of them in both chromosomes, 6 were presented as compound heterozygotes with additional c.3472-82delGGTTTAACCAT, c.3402delC, c.3121C〉T (p.RI041W) or unknown mutations. For one patient with liver cirrhosis and psychiatric disorder (Leipzig score 6), no mutations were found. Out of 16 first degree WD relatives, 11 (68.7%) were heterozygous for the c.3207C〉A (p.H1069Q) mutation. Two patients with fulminant WD died from acute liver failure and ii are in full remission under peniciilam  相似文献   
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