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Topic Review
Biography
Topic Review
Gallstone Disease
Gallstone disease (GSD) has, for many years, remained a high-cost, socially significant public health problem. Over the past decade, a number of studies have been carried out—both in humans and in animal models—confirming the role of the microbiota in various sections of the gastrointestinal tract as a new link in the etiopathogenesis of GSD. The microbiome of bile correlates with the bacterial composition of saliva, and the microbiome of the biliary tract has a high similarity with the microbiota of the duodenum. Pathogenic microflora of the oral cavity, through mechanisms of immunomodulation, can affect the motility of the gallbladder and the expression of mucin genes (Muc3, MUC4), and represent one of the promoters of stone formation in the gallbladder. The presence of H. pylori infection contributes to the formation of gallstones and affects the occurrence of complications of GSD, including acute and chronic cholecystitis, cholangitis, pancreatitis. Intestinal bacteria (Clostridium, Bifidobacterium, Peptostreptococcus, Bacteroides, Eubacterium, and Escherichia coli) participating in the oxidation and epimerization of bile acids can disrupt enterohepatic circulation and lead to the formation of gallstones. At the same time, cholecystectomy due to GSD leads to the further transformation of the composition of the microbiota in various parts of the gastrointestinal tract, increasing the risk of developing stomach cancer and colorectal cancer. Further research is required to determine the possibility of using the evaluation of the composition of the microbiota of the gastrointestinal and biliary tracts as an early diagnostic marker of various gastroenterological diseases.
676
27 Oct 2020
Topic Review
Oral Manifestations of IBD
Inflammatory bowel disease (IBD) comprises chronic heterogeneous disorders of unknown etiology, resulting from multifactorial environmental precipitants in genetically susceptible individuals. IBD are distinguished in two main phenotypes, Crohn’s disease (CD) and ulcerative colitis (UC), characterized by inflammation of the intestinal mucosa. While UC affects the rectum and a variable extent of the colon, CD can involve any location of the gastrointestinal (GI) tract, from the oral cavity to the anus. Furthermore, up to 36% of patients with IBD may have extra-intestinal manifestations (EIM) which can affect almost any organ of the body (eyes, joints, liver, pancreas, skin, blood, and mouth).
676
12 Jan 2021
Topic Review
Microbiome-Immune Interactions in Ulcerative Colitis
Inflammatory bowel disease (IBD) is a chronic autoimmune condition affecting the gastrointestinal (GI) tract. IBD includes Crohn’s disease (CD) and ulcerative colitis (UC), with UC characterized by inflammation of colonic mucosa and submucosa starting at the rectum and extending through the colon. The precise etiology of UC is unknown but is thought to involve a combination of environmental and genetic factors. Chief among these is the intestinal microbiome, which has been extensively studied both for its role in disease pathogenesis and possible treatment. In this review, we will discuss the microbial changes that have been described in UC, its interplay with host immune function, and evidence supporting its role as a potential therapeutic. We will also discuss parallels between UC, the microbiome and colitis-associated cancer (CAC).
674
05 Nov 2021
Topic Review
Human Herpesviruses
Human herpesviruses (HHVs): herpes simplex virus (HSV) types 1 (HSV-1) and 2 (HSV-2), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), HHV-6, HHV-7, and HHV-8, are known to be part of a family of DNA viruses that cause several diseases in humans. In clinical practice of inflammatory bowel disease (IBD), the complication of CMV enterocolitis, which is caused by CMV reactivation under disruption of intestinal barrier function, inflammation, or strong immunosuppressive therapy, is well known to affect the prognosis of disease. However, the relationship between other HHVs and IBD remains unclear.
669
27 Sep 2021
Topic Review
Major Genetic Factors Involved in Liver Diseases Pathogenesis
Over the past century, our genetic background has not changed, but chronic diseases are on the rise globally. In addition to the genetic component, the critical factors for many diseases are lifestyle, eating changes, exposure to drugs, xenobiotics, alcohol, smoking, polluted air, etc. These techniques include genome-wide association studies (GWAS) that allow the identification of unknown genetic risk factors, positional cloning of unknown genes associated with different diseases, the gene tests for single nucleotide variants (SNVs), and next-generation sequencing (NGS) of selected genes or/and the entire genome. Gut microbiome composition and its metabolites are not only regulating factors in carcinogenesis (including de novo after liver transplantation) but also in xenobiotics and anticancer treatment failure, observations that may be related to the genetic background of the individuals.
668
21 Nov 2023
Topic Review
Vitamin D Metabolism in Celiac Disease
Celiac disease is a chronic autoimmune disorder involving the small intestine, characterized by villous atrophy, crypt hyperplasia and an increase in intraepithelial lymphocytes. Due to both calcium malabsorption and immune activation, a high prevalence of bone mass derangement is evident in this condition, regardless of the presence of overt malabsorption. In untreated patients, secondary hyperparathyroidism is responsible for the hyperconversion of 25-vitamin D into 1,25-vitamin D making mandatory the determination of serum levels of both vitamin metabolites to avoid a wrong diagnosis of vitamin D deficit. A gluten-free diet allows for a normalization of bone and mineral metabolism, reverting these abnormalities and raising some doubts on the need for vitamin supplementation in all the patients.
665
19 Jan 2023
Topic Review
Clostridioides difficile
Infection in Inflammatory Bowel Diseases Patients
Clostridioides difficile (C. difficile) represents a major health burden with substantial economic and clinical impact. Patients with inflammatory bowel diseases (IBD) were identified as a risk category for Clostridioides difficile infection (CDI). In addition to traditional risk factors for C. difficile acquisition, IBD-specific risk factors such as immunosuppression, severity and extension of the inflammatory disease were identified. C. difficile virulence factors, represented by both toxins A and B, induce the damage of the intestinal mucosa and vascular changes, and promote the inflammatory host response. Given the potential life-threatening complications, early diagnostic and therapeutic interventions are required. The screening for CDI is recommended in IBD exacerbations, and the diagnostic algorithm consists of clinical evaluation, enzyme immunoassays (EIAs) or nucleic acid amplification tests (NAATs). An increased length of hospitalization, increased colectomy rate and mortality are the consequences of concurrent CDI in IBD patients. Selection of CD strains of higher virulence, antibiotic resistance, and the increasing rate of recurrent infections make the management of CDI in IBD more challenging.
664
08 Aug 2022
Topic Review
Developments in the Diagnosis of Postoperative Crohn’s Disease
Crohn’s disease (CD) is a chronic progressive inflammatory bowel disease leading to bowel damage and disability. The diagnosing recurrence in postoperative Crohn's disease is discussed.
663
06 Dec 2022
Topic Review
The Microbiome in Pancreatic Ductal Adenocarcinoma
Pancreatic cancer is a highly lethal cancer and less than 10% of patients survive the 5-year mark. The molecular and biological underpinnings leading to this dismal prognosis are well-described, however, translation of these findings with subsequent improvement of the poor prognosis has been slow. The complex and dynamic accumulation of microbes, also called the microbiome, has attracted scientific interest in the pathogenesis of several diseases including pancreatic cancer. Since then, a limited number of significant findings were published pointing towards an important role of the microbiome in cancer, in particular pancreatic cancer.
663
16 Dec 2022
Topic Review
Cytotoxicity of Thiopurine Drugs in Inflammatory Bowel Disease
As the principal representatives of thiopurines, 6-mercaptopurine (6MP) and its prodrug azathioprine (AZA) are primary immunomodulating agents. They are used for example to manage inflammatory bowel diseases (IBD), including ulcerative colitis (UC) and Crohn’s disease (CD), chronic inflammatory disorders of the gastrointestinal tract. Thiopurines were used to treat CD in the late 1960s and they are currently applied in around 60% of IBD patients.
663
31 Mar 2022
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