为了调查表皮细胞分裂原epigen基因是否与牙鲆变态发育有关,分析了从变态期牙鲆仔鱼cDNA文库中测序得到的epigen基因。发现epigen基因编码162个氨基酸,具有信号肽序列,一个跨膜结构域和EGF-like结构域。EGF-like结构域包含有可形成3个...为了调查表皮细胞分裂原epigen基因是否与牙鲆变态发育有关,分析了从变态期牙鲆仔鱼cDNA文库中测序得到的epigen基因。发现epigen基因编码162个氨基酸,具有信号肽序列,一个跨膜结构域和EGF-like结构域。EGF-like结构域包含有可形成3个二硫键的6个半胱氨酸残基,是表皮生长因子家族的结构特征。此外,利用荧光实时定量RT-PCR,调查了epigen基因在牙鲆眼睛移动过程中的变化。相比眼睛移动之前(17DAH,day after hatching),epigen基因在眼睛移动初期(19DAH)表达明显增强,为17DAH时的2.363倍;而在眼睛移动过程的高峰期(23DAH),表达量明显回落,相对19DAH的表达量降低了80%;变态结束后(27DAH)epigen基因的表达没有重新增强或进一步的回落,提示epigen基因可能与眼睛移动初期的变态发育事件有关,而与变态高峰期和变态后期的发育事件关系不明显。展开更多
ABSTRACT: Tabei (塔北) uplift is an area with the highest hydrocarbon enrichment in Tarim basin, and large oilfields have been found on Akekule (阿克库勒) arch at the middle section of Tabei uplift, with Ordovici...ABSTRACT: Tabei (塔北) uplift is an area with the highest hydrocarbon enrichment in Tarim basin, and large oilfields have been found on Akekule (阿克库勒) arch at the middle section of Tabei uplift, with Ordovician carbonate reservoirs. Storage space of the Ordovician carbonate reservoirs in the Akekule arch are mainly caves, pores and fractures resulted from dissolution and/or karstification. The Ordovician carbonate reservoirs are affected and modified by the diagenetie process in penecontemporaneous, epigenetic and burial periods and the multi-stage karstification related with deep hydrothermal activities, among which the most significant effect is from the meteoric water karstification related to the tectonic uplift from the end of Middle Ordovician to the end of Late Ordovician (end of O2-end of 03) and at the end of Middle Devonian (end of D2). Varied palacogeologic settings and tectonic features at different geologic periods lead to different fluid flowing patterns, karstification mechanisms and transformation features in different regions, which further influence the reservoir distribution. The paleo-uplifts at different periods, such as end of O2-end of 03 and end of D2, control the dominant development zones of karstification; the paleogeomorphology and faults resulted from tectonic uplift control the flowing depth of the karst fluid; and the lithology controls the position and extent of karst development.展开更多
Despite considerable advances in our understanding of cancer biology, early diagnosis of colorectal cancer remains elusive. Based on the adenoma-carcinoma sequence, cancer develops through the progressive accumulation...Despite considerable advances in our understanding of cancer biology, early diagnosis of colorectal cancer remains elusive. Based on the adenoma-carcinoma sequence, cancer develops through the progressive accumulation of mutations in key genes that regulate cell growth. However, recent mathematical modelling suggests that some of these genetic events occur prior to the development of any discernible histological abnormality. Cells acquire pro-tumourigenic mutations that are not able to produce morphological change but predispose to cancer formation. These cells can grow to form large patches of mucosa from which a cancer arises. This process has been termed "field cancerisation". It has received little attention in the scientific literature until recently. Several studies have now demonstrated cellular, genetic and epigenetic alterations in the macroscopically normal mucosa of colorectal cancer patients. In some reports, these changes were effectively utilised to identify patients with a neoplastic lesion suggesting potential application in the clinical setting. In this article, we present the scientific evidence to support field cancerisation in colorectal cancer and discuss important limitations that require further investigation. Characterisation of the field defect is necessary to enable early diagnosis of colorectal cancer and identify molecular targets for chemoprevention. Field cancerisation offers a promising prospect for experimental cancer research and has potential to improve patient outcomes in the clinical setting.展开更多
Growing evidence indicates that cancer incidence across the world is not similar,and it is more prevalent in certain populations than others,suggesting the critical role for dietary and lifestyle factors.For instance ...Growing evidence indicates that cancer incidence across the world is not similar,and it is more prevalent in certain populations than others,suggesting the critical role for dietary and lifestyle factors.For instance cancer incidence among people from the Indian subcontinent,where most spices are consumed,is much lower than that in the Western World.Spices have been consumed for centuries for a variety of purposes e.g.as flavoring agents,colorants,and preservatives.However,there is increasing evidence for the importance of plant-based foods in regular diet to lowering the risk of most chronic diseases,so spices are now emerging as more than just flavor aids,but as agents that can not only prevent but may even treat disease.Besides suppressing inflammatory pathways,spice-derived nutraceuticals can suppress survival,proliferation,invasion,and angiogenesis of tumor cells.Increasing evidence indicates that genetic alterations are relatively rare,and epigenetic changes(DNA methylation,histone modifications and expression of noncoding RNAs)plays a bigger role in human cancer,and can be easily influenced by environmental,lifestyle and dietary factors,and some estimates suggest that over two-thirds of the cancer incidence can be accounted for by the environmental and dietary factors alone.Among all these factors,diet is probably the single most important factor which may influence carcinogenesis more comprehensively,because diet is readily modifiable and have the potential to modulate multiple epigenetic processes.Polyphenols in dietary botanicals represent a versatile group of phytochemicals with many potentially beneficial activities in terms of disease prevention.Dietary polyphenols(bioflavanoids)have antioxidant and anti-inflammatory properties that might explain their chemopreventive effects.However,the actual therapeutic potential of these compounds may not have been completely realized due to lack of understanding on the effects of these agents on epigenetic modifications.Recent,but limited evidence indicates that some of the polyphenols,including curcumin(from turmeric),genestein(from soy),EGCG(from green tea),diallyl disulfide(from garlic),sulforaphane(from broccoli)and resveratrol(from grapes)may induce epigenetic changes in various cancer cell lines.This presentation will describe some of the current scientific evidence for the role of epigenetic alterations induced by curcumin and boswellia,in support of their anti-cancer activities,which provides a strong scientific foundation for preclinical and human clinical intervention studies in future.展开更多
文摘为了调查表皮细胞分裂原epigen基因是否与牙鲆变态发育有关,分析了从变态期牙鲆仔鱼cDNA文库中测序得到的epigen基因。发现epigen基因编码162个氨基酸,具有信号肽序列,一个跨膜结构域和EGF-like结构域。EGF-like结构域包含有可形成3个二硫键的6个半胱氨酸残基,是表皮生长因子家族的结构特征。此外,利用荧光实时定量RT-PCR,调查了epigen基因在牙鲆眼睛移动过程中的变化。相比眼睛移动之前(17DAH,day after hatching),epigen基因在眼睛移动初期(19DAH)表达明显增强,为17DAH时的2.363倍;而在眼睛移动过程的高峰期(23DAH),表达量明显回落,相对19DAH的表达量降低了80%;变态结束后(27DAH)epigen基因的表达没有重新增强或进一步的回落,提示epigen基因可能与眼睛移动初期的变态发育事件有关,而与变态高峰期和变态后期的发育事件关系不明显。
基金supported by the Scientific Research Project of SINOPEC Scientific Development Department (No. P08062)
文摘ABSTRACT: Tabei (塔北) uplift is an area with the highest hydrocarbon enrichment in Tarim basin, and large oilfields have been found on Akekule (阿克库勒) arch at the middle section of Tabei uplift, with Ordovician carbonate reservoirs. Storage space of the Ordovician carbonate reservoirs in the Akekule arch are mainly caves, pores and fractures resulted from dissolution and/or karstification. The Ordovician carbonate reservoirs are affected and modified by the diagenetie process in penecontemporaneous, epigenetic and burial periods and the multi-stage karstification related with deep hydrothermal activities, among which the most significant effect is from the meteoric water karstification related to the tectonic uplift from the end of Middle Ordovician to the end of Late Ordovician (end of O2-end of 03) and at the end of Middle Devonian (end of D2). Varied palacogeologic settings and tectonic features at different geologic periods lead to different fluid flowing patterns, karstification mechanisms and transformation features in different regions, which further influence the reservoir distribution. The paleo-uplifts at different periods, such as end of O2-end of 03 and end of D2, control the dominant development zones of karstification; the paleogeomorphology and faults resulted from tectonic uplift control the flowing depth of the karst fluid; and the lithology controls the position and extent of karst development.
基金Bowel Disease Research Foundation,United Kingdom
文摘Despite considerable advances in our understanding of cancer biology, early diagnosis of colorectal cancer remains elusive. Based on the adenoma-carcinoma sequence, cancer develops through the progressive accumulation of mutations in key genes that regulate cell growth. However, recent mathematical modelling suggests that some of these genetic events occur prior to the development of any discernible histological abnormality. Cells acquire pro-tumourigenic mutations that are not able to produce morphological change but predispose to cancer formation. These cells can grow to form large patches of mucosa from which a cancer arises. This process has been termed "field cancerisation". It has received little attention in the scientific literature until recently. Several studies have now demonstrated cellular, genetic and epigenetic alterations in the macroscopically normal mucosa of colorectal cancer patients. In some reports, these changes were effectively utilised to identify patients with a neoplastic lesion suggesting potential application in the clinical setting. In this article, we present the scientific evidence to support field cancerisation in colorectal cancer and discuss important limitations that require further investigation. Characterisation of the field defect is necessary to enable early diagnosis of colorectal cancer and identify molecular targets for chemoprevention. Field cancerisation offers a promising prospect for experimental cancer research and has potential to improve patient outcomes in the clinical setting.
文摘Growing evidence indicates that cancer incidence across the world is not similar,and it is more prevalent in certain populations than others,suggesting the critical role for dietary and lifestyle factors.For instance cancer incidence among people from the Indian subcontinent,where most spices are consumed,is much lower than that in the Western World.Spices have been consumed for centuries for a variety of purposes e.g.as flavoring agents,colorants,and preservatives.However,there is increasing evidence for the importance of plant-based foods in regular diet to lowering the risk of most chronic diseases,so spices are now emerging as more than just flavor aids,but as agents that can not only prevent but may even treat disease.Besides suppressing inflammatory pathways,spice-derived nutraceuticals can suppress survival,proliferation,invasion,and angiogenesis of tumor cells.Increasing evidence indicates that genetic alterations are relatively rare,and epigenetic changes(DNA methylation,histone modifications and expression of noncoding RNAs)plays a bigger role in human cancer,and can be easily influenced by environmental,lifestyle and dietary factors,and some estimates suggest that over two-thirds of the cancer incidence can be accounted for by the environmental and dietary factors alone.Among all these factors,diet is probably the single most important factor which may influence carcinogenesis more comprehensively,because diet is readily modifiable and have the potential to modulate multiple epigenetic processes.Polyphenols in dietary botanicals represent a versatile group of phytochemicals with many potentially beneficial activities in terms of disease prevention.Dietary polyphenols(bioflavanoids)have antioxidant and anti-inflammatory properties that might explain their chemopreventive effects.However,the actual therapeutic potential of these compounds may not have been completely realized due to lack of understanding on the effects of these agents on epigenetic modifications.Recent,but limited evidence indicates that some of the polyphenols,including curcumin(from turmeric),genestein(from soy),EGCG(from green tea),diallyl disulfide(from garlic),sulforaphane(from broccoli)and resveratrol(from grapes)may induce epigenetic changes in various cancer cell lines.This presentation will describe some of the current scientific evidence for the role of epigenetic alterations induced by curcumin and boswellia,in support of their anti-cancer activities,which provides a strong scientific foundation for preclinical and human clinical intervention studies in future.