Chronic atrophic gastritis （CAG） is an inflammatory condition characterized by the loss of gastric glandular structures which are replaced by connective tissue （non-metaplastic atrophy） or by glandular structures ...Chronic atrophic gastritis （CAG） is an inflammatory condition characterized by the loss of gastric glandular structures which are replaced by connective tissue （non-metaplastic atrophy） or by glandular structures inappropriate for location （metaplastic atrophy）. Epidemiological data suggest that CAG is associated with two different types of tumors： Intestinal-type gastric cancer （GC） and type I gastric carcinoid （T I GC）. The pathophysiological mechanisms which lead to the development of these gastric tumors are different, It is accepted that a multistep process initiating from Helico- bacterpylori-related chronic inflammation of the gastric mucosa progresses to CAG, intestinal metaplasia, dysplasia and, finally, leads to the development of GC. The T I GC is a gastrin-dependent tumor and the chronic elevation of gastrin, which is associated with CAG, stimulates the growth of enterochromaffin-like cells with their hyperplasia leading to the development of T I GC. Thus, several events occur in the gastric mucosa before the development of intestinatype GC and/ or T I GC and these take several years. Knowledge ofCAG incidence from superficial gastritis, its prevalence in different clinical settings and possible risk factors as- sociated with the progression of this condition to gastric neoplasias are important issues. This editorial intends to provide a brief review of the main studies regarding incidence and prevalence of CAG and risk factors for the development of gastric neoplasias.展开更多
Theories explaining the etiopathogenesis of inflammatory bowel disease （IBD） have been proposed ever since Crohn＇s disease （CD） and ulcerative colitis （UC） were recognized as the two major forms of the disease....Theories explaining the etiopathogenesis of inflammatory bowel disease （IBD） have been proposed ever since Crohn＇s disease （CD） and ulcerative colitis （UC） were recognized as the two major forms of the disease. Although the exact cause（s） and mechanisms of tissue damage in CD and UC have yet to be completely understood, enough progress has occurred to accept the following hypothesis as valid： IBD is an inappropriate immune response that occurs in genetically susceptible individuals as the result of a complex interaction among environmental factors, microbial factors, and the intestinal immune system. Among an almost endless list of environmental factors, smoking has been identified as a risk factor for CD and a protective factor for UC. Among microbial factors, no convincing evidence indicates that classical infectious agents cause IBD, while mounting evidence points to an abnormal immune response against the normal enteric flora as being of central importance. Gut inflammation is mediated by cells of the innate as well as adaptive immune systems, with the additional contribution of non-immune cells, such as epithelial, mesenchymal and endothelial cells, and platelets.展开更多
Primary liver cancer is an important cause of cancer death, and hepatocellular carcinoma （HCC） accounts for 70%-85% of total liver cancer worldwide. Chronic hepatitis B virus （HBV） infection contributes to 〉 75% ...Primary liver cancer is an important cause of cancer death, and hepatocellular carcinoma （HCC） accounts for 70%-85% of total liver cancer worldwide. Chronic hepatitis B virus （HBV） infection contributes to 〉 75% of HCC cases. High serum viral load is the most reliable indicator of viral replication in predicting development of HCC. HBV genotype C is closely associated with HCC in cirrhotic patients aged 〉 50 years, whereas genotype B is associated with development of HCC in non-cirrhotic young patients and postoperative relapse of HCC. Different HBV subgenotypes have distinct patterns of mutations, which are clearly associated with increased risk of HCC. Mutations accumulate during chronic HBV infection and predict occurrence of HCC. Chronic inflammation leads to increased frequency of viral mutation via cellular cytidine deaminase induction. Mutations are negatively selected by host immunity, whereas some immuno-escaped HBV mutants are active in hepatocarcinogenesis. Inflammatory pathways contribute to the inflammation-necrosis-regeneration process, ultimately HCC. Their hallmark molecules can predict malignancy in HBV-infected subjects. Continuing inflammation is involved in hepatocarcinogenesis and closely related to recurrence and metastasis. HBV load, genotype C, viral mutations and expression of inflammatory molecules in HBV-related HCC tissues are significantly associated with poor prognosis. Imbalance between intratumoral CD8^＋T cells and regulatory T cells or Thl and Th2 cytokines in peritumoral tissues can predict prognosis of HBV-related HCC. These factors are important for developing active prevention and surveillance of HBV-infected subjects who are more likely to develop HCC, or for tailoring suitable treatment to improve survival or postpone postoperative recurrence of HCC.展开更多
文摘Chronic atrophic gastritis （CAG） is an inflammatory condition characterized by the loss of gastric glandular structures which are replaced by connective tissue （non-metaplastic atrophy） or by glandular structures inappropriate for location （metaplastic atrophy）. Epidemiological data suggest that CAG is associated with two different types of tumors： Intestinal-type gastric cancer （GC） and type I gastric carcinoid （T I GC）. The pathophysiological mechanisms which lead to the development of these gastric tumors are different, It is accepted that a multistep process initiating from Helico- bacterpylori-related chronic inflammation of the gastric mucosa progresses to CAG, intestinal metaplasia, dysplasia and, finally, leads to the development of GC. The T I GC is a gastrin-dependent tumor and the chronic elevation of gastrin, which is associated with CAG, stimulates the growth of enterochromaffin-like cells with their hyperplasia leading to the development of T I GC. Thus, several events occur in the gastric mucosa before the development of intestinatype GC and/ or T I GC and these take several years. Knowledge ofCAG incidence from superficial gastritis, its prevalence in different clinical settings and possible risk factors as- sociated with the progression of this condition to gastric neoplasias are important issues. This editorial intends to provide a brief review of the main studies regarding incidence and prevalence of CAG and risk factors for the development of gastric neoplasias.
基金Supported by a grant from the Broad Medical Research Program toS.D
文摘Theories explaining the etiopathogenesis of inflammatory bowel disease （IBD） have been proposed ever since Crohn＇s disease （CD） and ulcerative colitis （UC） were recognized as the two major forms of the disease. Although the exact cause（s） and mechanisms of tissue damage in CD and UC have yet to be completely understood, enough progress has occurred to accept the following hypothesis as valid： IBD is an inappropriate immune response that occurs in genetically susceptible individuals as the result of a complex interaction among environmental factors, microbial factors, and the intestinal immune system. Among an almost endless list of environmental factors, smoking has been identified as a risk factor for CD and a protective factor for UC. Among microbial factors, no convincing evidence indicates that classical infectious agents cause IBD, while mounting evidence points to an abnormal immune response against the normal enteric flora as being of central importance. Gut inflammation is mediated by cells of the innate as well as adaptive immune systems, with the additional contribution of non-immune cells, such as epithelial, mesenchymal and endothelial cells, and platelets.
基金Supported by National Natural Science Foundation of China,No. 81025015 and No. 30921006
文摘Primary liver cancer is an important cause of cancer death, and hepatocellular carcinoma （HCC） accounts for 70%-85% of total liver cancer worldwide. Chronic hepatitis B virus （HBV） infection contributes to 〉 75% of HCC cases. High serum viral load is the most reliable indicator of viral replication in predicting development of HCC. HBV genotype C is closely associated with HCC in cirrhotic patients aged 〉 50 years, whereas genotype B is associated with development of HCC in non-cirrhotic young patients and postoperative relapse of HCC. Different HBV subgenotypes have distinct patterns of mutations, which are clearly associated with increased risk of HCC. Mutations accumulate during chronic HBV infection and predict occurrence of HCC. Chronic inflammation leads to increased frequency of viral mutation via cellular cytidine deaminase induction. Mutations are negatively selected by host immunity, whereas some immuno-escaped HBV mutants are active in hepatocarcinogenesis. Inflammatory pathways contribute to the inflammation-necrosis-regeneration process, ultimately HCC. Their hallmark molecules can predict malignancy in HBV-infected subjects. Continuing inflammation is involved in hepatocarcinogenesis and closely related to recurrence and metastasis. HBV load, genotype C, viral mutations and expression of inflammatory molecules in HBV-related HCC tissues are significantly associated with poor prognosis. Imbalance between intratumoral CD8^＋T cells and regulatory T cells or Thl and Th2 cytokines in peritumoral tissues can predict prognosis of HBV-related HCC. These factors are important for developing active prevention and surveillance of HBV-infected subjects who are more likely to develop HCC, or for tailoring suitable treatment to improve survival or postpone postoperative recurrence of HCC.
