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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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目的:测定市场上实际流通的商品胡桐泪药材中多糖的含量并对其单糖组成进行分析,以多糖为指标评价药材质量。方法:采用苯酚-硫酸法对总多糖进行含量测定;应用核磁共振氢谱(1H-NMR)分析单糖组成;运用高效凝胶渗透色谱(HPGPC)测定总多糖的分子量分布。结果:以葡萄糖计,4批新式胡桐泪总多糖含量平均值为(7.36±1.74)%,6批老式胡桐泪总多糖含量平均值为(1.53±0.99)%;新式与老式胡桐泪总多糖的单糖组成相似,主要由阿拉伯糖和半乳糖组成,还含有木糖、甘露糖、鼠李糖等,部分样品尚含有较高含量的葡萄糖;新旧类型样品总多糖在分子量分布上存在较大差异。结论:新式胡桐泪的总多糖含量平均值较老式高,以多糖含量为评价指标时,新式样品总体质量较老式更好;应用核磁共振氢谱可以快速、准确地鉴定单糖组成。  相似文献   
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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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Abstract

Objective—Myofibroblasts migrating from adventitia have been suggested to constitute a majority of neointimal cells after angioplasty. We sought to examine this hypothesis by use of smoothelin, which is a marker for the quiescent smooth muscle cell (SMC) phenotype while not expressed by myofibroblasts. Design—Balloon angioplasty was performed in left iliac arteries of 25 rabbits that were killed after 3-56 days. Arterial cross-sections were immunostained for (X-actin (general marker), smoothelin (quiescent SMC phenotype), and Ki-67 (proliferative phenotype).

Results—Adventitial cells became transiently actinpositive (myofibroblasts) but did not express smoothelin at any time point. In media, angioplasty induced transient proliferation and coinciding transient decrease in smoothelin expression. Neointimal cells, present 7 days after angioplasty, were initially proliferating and smoothelin-negative but changed to non-proliferating, smoothelin-positive cells after 56 days where 82 ± 10% of cells stained positive for smoothelin. This phenotypic modulation of medial and intimal cells began in media and moved gradually towards the lumen.

Conclusion—At late follow-up, the majority of intimal cells are smoothelin-positive indicating that adventitial myofibroblasts play no major role for neointima formation.  相似文献   
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To evaluate the impact of a community health worker intervention (CHW) (referred to as Personalized Support for Progress (PSP)) on all-cause health care utilization and cost of care compared with Enhanced Screening and Referral (ESR) among women with depression. A total of 223 patients (111 in PSP and 112 in ESR randomly assigned) from three women’s health clinics with elevated depressive symptoms were enrolled in the study. Their electronic health records were queried to extract all-cause health care encounters along with the corresponding billing information 12 months before and after the intervention, as well as during the first 4-month intervention period. The health care encounters were then grouped into three mutually exclusive categories: high-cost (> US$1000 per encounter), medium-cost (US$201–$999), and low-cost (≤ US$200). A difference-in-difference analysis of mean total charge per patient between PSP and ESR was used to assess cost differences between treatment groups. The results suggest the PSP group was associated with a higher total cost of care at the baseline; taking this baseline difference into account, the PSP group was associated with lower mean total charge amounts (p = 0.008) as well as a reduction in the frequency of high-cost encounters (p < 0.001) relative to the ESR group during the post-intervention period. Patient-centered interventions that address unmet social needs in a high-cost population via CHW may be a cost-effective approach to improve quality of care and patient outcomes.

  相似文献   
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