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51.
Non-invasive detection of fecal protein kinase C betaII and zeta messenger RNA: putative biomarkers for colon cancer 总被引:2,自引:0,他引:2
Davidson LA; Aymond CM; Jiang YH; Turner ND; Lupton JR; Chapkin RS 《Carcinogenesis》1998,19(2):253-257
We have developed a non-invasive method utilizing feces, containing
sloughed colonocytes, as a sensitive technique for detecting diagnostic
colonic biomarkers. In this study, we used the rat colon carcinogenesis
model to determine if changes in fecal protein kinase C (PKC) expression
have predictive value in monitoring the neoplastic process. Weanling rats
were injected with saline or azoxymethane (AOM) and 36 weeks later fecal
samples and mucosa were collected, poly A+ RNA isolated, and quantitative
RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and
zeta mRNA levels were altered by the presence of a tumor, with
tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII
expression as compared with animals without tumors. In addition,
AOM-injection increased mucosal PKC betaII mRNA expression compared with
saline controls. No effect of tumor incidence on mucosal PKC betaII
expression was observed. In contrast, fecal PKC zeta expression was
2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus
saline. Since tumor incidence exerts a reciprocal effect on fecal PKC
betaII and zeta mRNA expression, data were also expressed as the ratio
between PKC betaII and zeta. The isozyme ratio was strongly related to
tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25,
animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that
the expression of fecal PKC betaII and zeta may serve as a noninvasive
marker for development of colon tumors. A sensitive technique for the
detection of colon cancer is of importance since early diagnosis can
substantially reduce mortality.
相似文献
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M Ghosh H Kamma T Kawamoto N Koike M Miwa V K Kapoor N Krishnani S Agrawal N Ohkohchi T Todoroki 《European journal of surgical oncology》2005,31(8):891-896
AIM: The significance of MUC 1 expression in the gallbladder tissues in relation to cancer and non-cancer disease is not well understood. The aim of this study was to clarify the significance of MUC 1 expression. MATERIALS AND METHODS: A monoclonal antibody (CA 15--3; DF 3) was applied to stain MUC 1 core protein in surgical specimens. RESULTS: MUC 1 expression is significantly higher (p<0.0001) in gallbladder cancer (69/88) compare to non-cancerous tissue, while, very trace in normal and inflammatory tissues. The expression rate was significantly lower (p<0.0001) when the cancer did not penetrate the mucosal layer than when cancers did penetrate this layer. The MUC 1 expression rate was (4/14) in T1 tumours, (11/14) in T4, (40/45) in T3, and (14/15) in T2, respectively. Every cell of normal and inflammatory mucosa, and T1 cancers had the polarized pattern. The depolarized pattern was dominant in cancer cells from the advanced tumours of T2, T3 and T4. That is, (45/74) of cancer cells from the mucosal layer and (58/74) of penetrating cancer cells in submucosal layer had the depolarized pattern. There was no significant correlation of MUC 1 expression rate and staining pattern with cancer differentiation and microscopic venous invasion. On the other hand, lymphatic vessel invasion was significantly correlated with the staining pattern but not with expression rate. CONCLUSION: MUC 1 core protein expression rate and pattern are suggesting that MUC 1 core protein would be a marker of malignant transformation of gallbladder epithelium and its depolarized expression would also be a marker of invasion of gallbladder cancer. 相似文献
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Rice JP Hartz SM Agrawal A Almasy L Bennett S Breslau N Bucholz KK Doheny KF Edenberg HJ Goate AM Hesselbrock V Howells WB Johnson EO Kramer J Krueger RF Kuperman S Laurie C Manolio TA Neuman RJ Nurnberger JI Porjesz B Pugh E Ramos EM Saccone N Saccone S Schuckit M Bierut LJ;the GENEVA Consortium 《Addiction (Abingdon, England)》2012,107(11):2019-2028
AIMS: Nicotine dependence is a highly heritable disorder associated with severe medical morbidity and mortality. Recent meta-analyses have found novel genetic loci associated with cigarettes per day (CPD), a proxy for nicotine dependence. The aim of this paper is to evaluate the importance of phenotype definition (i.e. CPD versus Fagerstr?m Test for Cigarette Dependence (FTCD) score as a measure of nicotine dependence) on genome-wide association studies of nicotine dependence. DESIGN: Genome-wide association study. SETTING: Community sample. PARTICIPANTS: A total of 3365 subjects who had smoked at least one cigarette were selected from the Study of Addiction: Genetics and Environment (SAGE). Of the participants, 2267 were European Americans, 999 were African Americans. MEASUREMENTS: Nicotine dependence defined by FTCD score ≥4, CPD. FINDINGS: The genetic locus most strongly associated with nicotine dependence was rs1451240 on chromosome 8 in the region of CHRNB3 [odds ratio (OR)?=?0.65, P?=?2.4?×?10(-8) ]. This association was further strengthened in a meta-analysis with a previously published data set (combined P?=?6.7?×?10(-16) , total n?=?4200). When CPD was used as an alternate phenotype, the association no longer reached genome-wide significance (β?=?-0.08, P?=?0.0004). CONCLUSIONS: Daily cigarette consumption and the Fagerstrom Test for Cigarette Dependence show different associations with polymorphisms in genetic loci. 相似文献
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Rupesh Agrawal Hnin Hnin Oo Praveen Kumar Balne Lisa Ng Louis Tong Yee Sin Leo 《Ocular immunology and inflammation》2018,26(5):654-659
Zika virus (ZIKV), a mosquito-borne flavivirus, is the latest global health concern. Transmission is mainly via Aedes mosquitoes and the infection can be diagnosed on molecular or serologic testings. It typically causes a mild self-remitting illness of low-grade fever, maculopapular rash, and myalgia, but when severe, it is associated with neurological deficits and congenital structural defects. Ocular manifestations are usually mild like nonpurulent conjunctivitis in adults, though it may be linked to uveitis, maculopathy, and hypertensive iridocyclitis. Ocular signs seem to be more significant in congenital ZIKV—macular pigment mottling, neuroretinal atrophy with macular involvement, iris coloboma, and changes in retinal vasculature are noted in infants with infected mothers. Risk factors include ZIKV infection in first trimester and smaller cephalic diameter at birth. Hence, ophthalmic examination in newborns is now recommended. Currently, prevention and active surveillance are integral as there is no known vaccine, and treatment is only symptomatic. 相似文献
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Anshul Goel Dhananjaya Sabat Pritam Agrawal 《Journal of Clinical Orthopaedics and Trauma》2016,7(1):61-65
Medial condyle Hoffa fractures are intra articular injuries, which require prompt anatomical reduction and internal fixation. Arthroscopy-guided fixation of these fractures has also been advocated; the advantages include avoidance of soft tissue dissection, fast recovery and mobilization. We describe a case of a 28-year-old male patient presenting with a 10-day-old medial condylar Hoffa fracture. Skin condition prevented from conventional open reduction and internal fixation; hence, taking note of the urgency of fixation of an intraarticular fracture, arthroscopic-assisted minimally invasive approach was performed with good outcome. 相似文献