Crohn’s disease(CD)is a chronic inflammatory condition that plagues millions all over the world.This debilitating bowel disease can start in early childhood and continue into late adulthood.Signs and symptoms are usu...Crohn’s disease(CD)is a chronic inflammatory condition that plagues millions all over the world.This debilitating bowel disease can start in early childhood and continue into late adulthood.Signs and symptoms are usually many and multiple tests are often required for the diagnosis and confirmation of this disease.However,little is still understood about the cause(s)of CD.As a result,several theories have been proposed over the years.One theory in particular is that Mycobacterium avium subspecies paratuberculosis(MAP)is intimately linked to the etiology of CD.This fastidious bacterium also known to cause Johne’s disease in cattle has infected the intestines of animals for years.It is believed that due to the thick,waxy cell wall of MAP it is able to survive the process of pasteurization as well as chemical processes seen in irrigation purification systems.Subsequently meat,dairy products and water serve as key vehicles in the transmission of MAP infection to humans(from farm to fork)who have a genetic predisposition,thus leading to the development of CD.The challenges faced in culturing this bacterium from CD are many.Examples include its extreme slow growth,lack of cell wall,low abundance,and its mycobactin dependency.In this review article,data from 60 studies showing the detection and isolation of MAP by PCR and culture techniques have been reviewed.Although this review may not be 100%comprehensive of all studies,clearly the majority of the studies overwhelmingly and definitively support the role of MAP in at least30%-50%of CD patients.It is very possible that lack of detection of MAP from some CD patients may be due to the absence of MAP role in these patients.The latter statement is conditional on utilization of methodology appropriate for detection of human MAP strains.Ultimately,stratification of CD and inflammatory bowel disease patients for the presence or absence of MAP is necessary for appropriate and effective treatment which may lead to a cure.展开更多
Autism spectrum disorders(ASD)comprise a group of neurodevelopmental abnormalities that begin in early childhood and are characterized by impairment of social communication and behavioral problems including restricted...Autism spectrum disorders(ASD)comprise a group of neurodevelopmental abnormalities that begin in early childhood and are characterized by impairment of social communication and behavioral problems including restricted interests and repetitive behaviors.Several genes have been implicated in the pathogenesis of ASD,most of them are involved in neuronal synaptogenesis.A number of environmental factors and associated conditions such as gastrointestinal(GI)abnormalities and immune imbalance have been linked to the pathophysiology of ASD.According to the March 2012 report released by United States Centers for Disease Control and Prevention,the prevalence of ASD has sharply increased during the recent years and one out of 88 children suffers now from ASD symptoms.Although there is a strong genetic base for the disease,several associated factors could have a direct link to the pathogenesis of ASD or act as modifiers of the genes thus aggravating the initial problem.Many children suffering from ASD have GI problems such as abdominal pain,chronic diarrhea,constipation,vomiting,gastroesophageal reflux,and intestinal infections.A number of studies focusing on the intestinal mucosa,its permeability,abnormal gut development,leaky gut,and other GI problem raised many questions but studies were somehow inconclusive and an expert panel of American Academy of Pediatrics has strongly recommended further investigation in these areas.GI tract has a direct connection with the immune system and an imbalanced immune response is usually seen in ASD children.Maternal infection or autoimmune diseases have been suspected.Activation of the immune system during early development may have deleterious effect on various organs including the nervous system.In this review we revisited briefly the GI and immune system abnormalities and neuropeptide imbalance and their role in the pathophysiology of ASD and discussed some future research directions.展开更多
文摘Crohn’s disease(CD)is a chronic inflammatory condition that plagues millions all over the world.This debilitating bowel disease can start in early childhood and continue into late adulthood.Signs and symptoms are usually many and multiple tests are often required for the diagnosis and confirmation of this disease.However,little is still understood about the cause(s)of CD.As a result,several theories have been proposed over the years.One theory in particular is that Mycobacterium avium subspecies paratuberculosis(MAP)is intimately linked to the etiology of CD.This fastidious bacterium also known to cause Johne’s disease in cattle has infected the intestines of animals for years.It is believed that due to the thick,waxy cell wall of MAP it is able to survive the process of pasteurization as well as chemical processes seen in irrigation purification systems.Subsequently meat,dairy products and water serve as key vehicles in the transmission of MAP infection to humans(from farm to fork)who have a genetic predisposition,thus leading to the development of CD.The challenges faced in culturing this bacterium from CD are many.Examples include its extreme slow growth,lack of cell wall,low abundance,and its mycobactin dependency.In this review article,data from 60 studies showing the detection and isolation of MAP by PCR and culture techniques have been reviewed.Although this review may not be 100%comprehensive of all studies,clearly the majority of the studies overwhelmingly and definitively support the role of MAP in at least30%-50%of CD patients.It is very possible that lack of detection of MAP from some CD patients may be due to the absence of MAP role in these patients.The latter statement is conditional on utilization of methodology appropriate for detection of human MAP strains.Ultimately,stratification of CD and inflammatory bowel disease patients for the presence or absence of MAP is necessary for appropriate and effective treatment which may lead to a cure.
文摘Autism spectrum disorders(ASD)comprise a group of neurodevelopmental abnormalities that begin in early childhood and are characterized by impairment of social communication and behavioral problems including restricted interests and repetitive behaviors.Several genes have been implicated in the pathogenesis of ASD,most of them are involved in neuronal synaptogenesis.A number of environmental factors and associated conditions such as gastrointestinal(GI)abnormalities and immune imbalance have been linked to the pathophysiology of ASD.According to the March 2012 report released by United States Centers for Disease Control and Prevention,the prevalence of ASD has sharply increased during the recent years and one out of 88 children suffers now from ASD symptoms.Although there is a strong genetic base for the disease,several associated factors could have a direct link to the pathogenesis of ASD or act as modifiers of the genes thus aggravating the initial problem.Many children suffering from ASD have GI problems such as abdominal pain,chronic diarrhea,constipation,vomiting,gastroesophageal reflux,and intestinal infections.A number of studies focusing on the intestinal mucosa,its permeability,abnormal gut development,leaky gut,and other GI problem raised many questions but studies were somehow inconclusive and an expert panel of American Academy of Pediatrics has strongly recommended further investigation in these areas.GI tract has a direct connection with the immune system and an imbalanced immune response is usually seen in ASD children.Maternal infection or autoimmune diseases have been suspected.Activation of the immune system during early development may have deleterious effect on various organs including the nervous system.In this review we revisited briefly the GI and immune system abnormalities and neuropeptide imbalance and their role in the pathophysiology of ASD and discussed some future research directions.
