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排序方式: 共有754条查询结果,搜索用时 15 毫秒
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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
3.
Daniel Ranch Martin YH Zhang Anthony A Portale Farzana Perwad 《Journal of bone and mineral research》2011,26(8):1883-1890
In X‐linked hypophosphatemia (XLH) and in its murine homologue, the Hyp mouse, increased circulating concentrations of fibroblast growth factor 23 (FGF‐23) are critical to the pathogenesis of disordered metabolism of phosphate (Pi) and 1,25‐dihydroxyvitamin D [1,25(OH)2D]. In this study, we hypothesized that in Hyp mice, FGF‐23‐mediated suppression of renal 1,25(OH)2D production and Pi reabsorption depends on activation of mitogen‐activated protein kinase (MAPK) signaling. Wild‐type and Hyp mice were administered either vehicle or the MEK inhibitor PD0325901 (12.5 mg/kg) orally daily for 4 days. At baseline, the renal abundance of early growth response 1 (egr1) mRNA was approximately 2‐fold greater in Hyp mice than in wild‐type mice. Treatment with PD0325901 greatly suppressed egr1 mRNA abundance in both wild‐type and Hyp mice. In Hyp mice, PD0325901 induced an 8‐fold increase in renal 1α‐hydroxylase mRNA expression and a 4‐fold increase in serum 1,25(OH)2D concentrations compared with vehicle‐treated Hyp mice. Serum Pi levels in Hyp mice increased significantly after treatment with PD0325901, and the increase was associated with increased renal Npt2a mRNA abundance and brush‐border membrane Npt2a protein expression. These findings provide evidence that in Hyp mice, MAPK signaling is constitutively activated in the kidney and support the hypothesis that the FGF‐23‐mediated suppression of renal 1,25(OH)2D production and Pi reabsorption depends on activation of MAPK signaling via MEK/ERK1/2. These findings demonstrate the physiologic importance of MAPK signaling in the actions of FGF‐23 in regulating renal 1,25(OH)2D and Pi metabolism. © 2011 American Society for Bone and Mineral Research 相似文献
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肝硬变和肝细胞癌组织中CD54,CD80,CD86和HLA-ABC的表达 总被引:7,自引:7,他引:0
目的探讨CD54,CD80,CD86和HLA-ABC在肝硬变的免疫损伤和抗肝癌免疫中的意义.方法用免疫组化方法检测CD54,CD80,CD86和HLA-ABC在肝硬变(n=30)和肝癌(n=48)中的表达、定位和分布.结果在LC中,CD54阳性率为40%(12/30),CD80为50%(15/30),CD86为37%(11/30),HLA-ABC为63%(19/30);在HCC中,CD54阳性率为77%(37/48),CD80为19%(9/47),CD86为13%(6/47),HLA-ABC为30%(12/40);在癌周围组织(PCT)中,CD54为阴性,CD80阳性率为44%(14/32),CD86为47%(15/32),HLA-ABC为53%(17/32).统计学处理显示,在LC中,CD54阳性率显著低于HCC(P<0.01);CD80(P<0.01),CD86(P<0.05)和HLA-ABC(P<0.01)均显著高于HCC;而与PCT无显著差别.在HCC中,CD80(P<0.05),CD86(P<0.01),HLA-ABC(P<0.05),均显著低于PCT.结论 CD54,CD80,CD86和HLA-ABC在LC和HCC中的同时足量表达有可能引起肝细胞损伤和有效抗肿瘤免疫应答,而CD80,CD86表达的缺失或不足可能是HCC产生免疫逃避的主要原因. 相似文献
7.
Kim YH; de Kretser DM; Temple-Smith PD; Hearn MT; McFarlane JR 《Molecular human reproduction》1997,3(4):307-313
Using mechanical and chemical dissection methods, fibrous sheath was
isolated both from normal ejaculated human spermatozoa and from rabbit
cauda epididymal spermatozoa. The same techniques did not produce a pure
preparation of fibrous sheath from ejaculated rabbit spermatozoa,
suggesting that further cross-linking and stabilization of sperm structures
occurs in response to components of the seminal plasma. The isolation
procedures were monitored by phase contrast microscopy and the purity of
the fibrous sheath was verified by electron microscopy. Sodium dodecyl
sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of isolated human
fibrous sheath revealed at least 14 protein bands of which the most
intensely stained were of molecular weight 84, 72, 66.2, 57, 32 and 28.5
kDa. The rabbit fibrous sheath revealed at least 10 protein bands, of which
the most intensely stained were 35.2, 32.7 and 28.5 kDa. The amino acid
composition of the purified fibrous sheath from human and rabbit
spermatozoa was similar, being high in aspartic acid and/or asparagine and
glutamic acid and/or glutamine, serine, alanine, leucine, lysine and
glycine, but low in histidine, tyrosine and isoleucine. This composition is
similar to that reported for the rat and suggests that mammalian sperm tail
fibrous sheaths are composed of similar types of proteins, although there
are apparent differences in protein components between species.
相似文献
8.
Chou SP Lee HK Cho MJ Park JI Dawson DA Grant BF 《Alcoholism, clinical and experimental research》2012,36(4):654-662
Background: The strong comorbidity between substance use disorders (SUDs) and mood and anxiety disorders has been well documented. In view of lack of research findings addressing the co‐occurrence of SUDs and mood and anxiety disorders, this study examined the pattern of comorbidity of alcohol use disorders (AUDs) and nicotine dependence (ND) between 2 culturally diverse countries, the United States and South Korea. Methods: Using the nationally representative samples of the U.S. and Korean general populations, we directly compared rates and comorbidity patterns of AUDs, ND, and mood and anxiety disorders between the 2 countries. We further examined the rates and the comorbidity pattern among individuals with AUDs who sought treatment in the last 12 months. Twelve‐month prevalence rates were derived to estimate country differentials, and odds ratios (ORs) and 95% confidence intervals were estimated to measure the strength of comorbid associations while adjusting for all sociodemographic characteristics in multivariate logistic models specific to each country. Results: The 12‐month prevalence rates of AUDs, ND, and any mood disorder and any anxiety disorder were 9.7, 14.4, 9.5, and 11.9% among Americans, whereas the corresponding rates were 7.1, 6.6, 2.0, and 5.2% among Koreans. These rates were significantly greater (except for any AUD) among Americans than among their Korean counterparts. With respect to comorbidity, both countries showed comparable patterns that the prevalence rates of mood and anxiety disorders were consistently the highest among persons with alcohol dependence (AD). Also, a disparate pattern was observed in Korea that the prevalence rates of mood and anxiety disorders were generally lower among individuals with ND than among those with alcohol abuse and AD. Furthermore, despite significantly greater prevalence of AD in Korea (5.1%) than in the United States (4.4%), alcohol‐dependent Americans were 4 times (OR = 3.93) more likely to seek treatment compared to their Korean counterparts. Conclusions: Our results indicated that the prevalence of AD in Korea was substantially greater than that in both Western and other Asian countries, suggesting a maladaptive pattern of alcohol use in Korea, which is different from the general use pattern of other East Asian countries. The low rate of treatment utilization among Koreans might be attributable to perceived social stigma toward SUDs or mental health problems despite the fact that the Korean government offers national health insurance. 相似文献
9.
Seung-Min Lee So Hee Dho Sung-Kyu Ju Jin-Soo Maeng Jeong-Yoon Kim Ki-Sun Kwon 《Biogerontology》2012,13(5):525-536
Carbohydrate metabolism changes during cellular senescence. Cytosolic malate dehydrogenase (MDH1) catalyzes the reversible reduction of oxaloacetate to malate at the expense of reduced nicotinamide adenine dinucleotide (NADH). Here, we show that MDH1 plays a critical role in the cellular senescence of human fibroblasts. We observed that the activity of MDH1 was reduced in old human dermal fibroblasts (HDFs) [population doublings (PD) 56], suggesting a link between decreased MDH1 protein levels and aging. Knockdown of MDH1 in young HDFs (PD 20) and the IMR90 human fibroblast cell line resulted in the appearance of significant cellular senescence features, including senescence-associated β-galactosidase staining, flattened and enlarged morphology, increased population doubling time, and elevated p16INK4A and p21CIP1 protein levels. Cytosolic NAD/NADH ratios were decreased in old HDFs to the same extent as in MDH1 knockdown HDFs, suggesting that cytosolic NAD depletion is related to cellular senescence. We found that AMP-activated protein kinase, a sensor of cellular energy, was activated in MDH1 knockdown cells. We also found that sirtuin 1 (SIRT1) deacetylase, a controller of cellular senescence, was decreased in MDH1 knockdown cells. These results indicate that the decrease in MDH1 and subsequent reduction in NAD/NADH ratio, which causes SIRT1 inhibition, is a likely carbohydrate metabolism-controlled cellular senescence mechanism. 相似文献
10.
Soo-Jeong Kim June-Won Cheong Dae-Young Kim Je-Hwan Lee Kyoo-Hyung Lee Yeo-Kyeoung Kim Hyeong-Joon Kim Ik-Chan Song Deog-Yeon Jo Jeong-Ok Lee Soo-Mee Bang Jinny Park Jae Hoon Lee Won-Sik Lee Young-Don Joo Chi Hoon Maeng Hwi-Joong Yoon Na-Ri Lee Jae-Yong Kwak Kyoung Ha Kim Jong-Ho Won Bo Ram Han Dae Young Zang Joon Ho Moon Sang Kyun Sohn Sung Hwa Bae Hun Mo Ryoo Sung-Yong Kim Mark Hong Lee Yoo Hong Min 《International journal of hematology》2014,100(2):141-151
The present study sought to elucidate the role of induction and consolidation therapy in elderly patients. We retrospectively collected data of 477 patients who were aged over 60 years at the time of acute myeloid leukemia (AML) diagnosis. The median overall survival (OS) was 339 days in the induction group (n = 266) and 86 days in the best supportive care group (n = 211) (P < 0.001). In the induction group, the complete remission (CR) rate was 58.3 %, and treatment-related death was 15.4 %. Successful induction was related to good performance [Eastern Cooperative Oncology Group (ECOG <2)] [hazard ratio (HR) 3.215; P = 0.002]. Mortality correlated with failure to achieve CR (HR 4.059; P < 0.001) and poor performance status (ECOG >2) (HR 2.731; P = 0.035). In CR patients, poor karyotype and absence of consolidation (HR 2.313; P = 0.003) correlated with mortality. More than one cycle of consolidation was associated with better OS (P < 0.001). Lack of salvage therapy was associated with mortality in patients who did not achieve CR (HR 3.223; P = 0.005). Intensive induction in patients with good performance and >1 cycle of consolidation after CR may be the best strategy for improving OS in elderly AML patients. 相似文献