Follicular T-helper (Tfh) cells contribute to pathogen-specific antibody responses by providing maturation signals to B cells. In mice with viral infections, virus-specific Tfh cells expand and are required to contain the infection. However, less is known about human virus-specific Tfh cells or their functions during infection. We investigated whether virus-specific CD4+ T cells from patients with hepatitis C virus (HCV) infection had phenotypic or functional features of Tfh cells and contribute to the production of HCV-specific antibodies.

It is not clear whether symptoms alone can be used to estimate the biologic activity of eosinophilic esophagitis (EoE). We aimed to evaluate whether symptoms can be used to identify patients with endoscopic and histologic features of remission.

The risk of colorectal neoplasms among siblings of patients with advanced adenomas is not clear. We determined the prevalence of advanced adenomas in the siblings of patients with advanced adenomas and compared it with that of siblings of individuals without these lesions.

Obesity and alcohol consumption contribute to steatohepatitis, which increases the risk for hepatitis C virus (HCV)-associated hepatocellular carcinomas (HCCs). Mouse hepatocytes that express HCV-NS5A in liver up-regulate the expression of Toll-like receptor 4 (TLR4), and develop liver tumors containing tumor-initiating stem-like cells (TICs) that express NANOG. We investigated whether the TLR4 signals to NANOG to promote the development of TICs and tumorigenesis in mice placed on a Western diet high in cholesterol and saturated fat (HCFD).

Hereditary hemochromatosis is a heterogeneous group of genetic disorders characterized by parenchymal iron overload. It is caused by defective expression of liver hepcidin, the main regulator of iron homeostasis. Iron stimulates the gene encoding hepcidin (HAMP) via the bone morphogenetic protein (BMP)6 signaling to SMAD. Although several genetic factors have been found to cause late-onset hemochromatosis, many patients have unexplained signs of iron overload. We investigated BMP6 function in these individuals.

Children with very early-onset inflammatory bowel disease (VEO-IBD), those diagnosed at less than 5 years of age, are a unique population. A subset of these patients present with a distinct phenotype and more severe disease than older children and adults. Host genetics is thought to play a more prominent role in this young population, and monogenic defects in genes related to primary immunodeficiencies are responsible for the disease in a small subset of patients with VEO-IBD.

Only few case reports of mucinous cystic pancreatic neoplasm containing an undifferentiated carcinoma with osteoclast-like giant cells have been described in the literature. In the majority of cases this unusual association of tumors seems related to a favorable outcome. We present the second case of an indeterminate mucin-producting cystic neoplasm containing an area of carcinoma with osteoclast-like giant cells. The specific features of the two histotypes and the rapid course of the disease make our clinical case remarkable.

The diagnosis of associated choledocholithiasis prior to cholecystectomy for patients with gallstones is important for the surgical decision and treatment efficacy. However, whether ultrasound is sufficient for preoperative diagnosis of choledocholithiasis remains controversial, with different opinions on whether routine magnetic resonance cholangiopancreatography (MRCP) is needed to detect the possible presence of common bile duct (CBD) stones.

Liver sinusoidal endothelial cells (SECs), hepatic stellate cells (HSCs) and Kupffer cells (KCs) are involved in the development of liver fibrosis and represent a potential therapeutic target. The therapeutic effects on liver fibrosis of sorafenib, a multiple tyrosine kinase inhibitor, and gadolinium chloride (GdCl3), which depletes KCs, were evaluated in rats.

Hepatitis C virus (HCV) is a major cause of chronic liver disease and cancer. Vietnamese Americans are at high risk of HCV infection, with men having the highest US incidence of liver cancer. This study examines an intervention to improve HCV knowledge among Vietnamese Americans.

Leukocyte trafficking to the small and large intestines is tightly controlled to maintain intestinal immune homeostasis, mediate immune responses, and regulate inflammation. A wide array of chemoattractants, chemoattractant receptors, and adhesion molecules expressed by leukocytes, mucosal endothelium, epithelium, and stromal cells controls leukocyte recruitment and microenvironmental localization in intestine and in the gut-associated lymphoid tissues (GALTs). Naive lymphocytes traffic to the gut-draining mesenteric lymph nodes where they undergo antigen-induced activation and priming; these processes determine their memory/effector phenotypes and imprint them with the capacity to migrate via the lymph and blood to the intestines. Mechanisms of T-cell recruitment to GALT and of T cells and plasmablasts to the small intestine are well described. Recent advances include the discovery of an unexpected role for lectin CD22 as a B-cell homing receptor GALT, and identification of the orphan G-protein-coupled receptor 15 (GPR15) as a T-cell chemoattractant/trafficking receptor for the colon. GPR15 decorates distinct subsets of T cells in mice and humans, a difference in species that could affect translation of the results of mouse colitis models to humans. Clinical studies with antibodies to integrin α4β7 and its vascular ligand mucosal vascular addressin cell adhesion molecule 1 are proving the value of lymphocyte trafficking mechanisms as therapeutic targets for inflammatory bowel diseases. In contrast to lymphocytes, cells of the innate immune system express adhesion and chemoattractant receptors that allow them to migrate directly to effector tissue sites during inflammation. We review the mechanisms for innate and adaptive leukocyte localization to the intestinal tract and GALT, and discuss their relevance to human intestinal homeostasis and inflammation.

There have been increasing reports of food-borne zoonotic transmission of hepatitis E virus (HEV) genotype 3, which causes chronic infections in immunosuppressed patients. We performed phylogenetic analyses of the HEV sequence (partial and full-length) from 1 patient from the Middle East who underwent liver transplantation, and compared it with other orthohepevirus A sequences. We found the patient to be infected by camelid HEV. This patient regularly consumed camel meat and milk, therefore camelid HEV, which is genotype 7, might infect human beings. Our finding links consumption of camel-derived food products to post-transplantation hepatitis E, which, if detected at early stages, can be cured with antiviral therapy and reduced administration of immunosuppressive agents.

Previous studies have indicated that serotonin-3-receptor antagonists might have a sex-specific effect in patients with irritable bowel syndrome with diarrhea (IBS-D). Alosetron has been approved for the treatment of only women, and ramosetron has been approved for the treatment for only men. We performed a randomized, placebo-controlled, phase 3 study to determine whether ramosetron reduces symptoms of IBS-D in women.

Gastric cancer is usually diagnosed in an advanced stage of disease and treatment options are sparse. Trastuzumab was recently approved for metastatic or locally advanced carcinomas arising in the stomach or in the gastroesophageal junction in patients with HER2-positive tumors. However, data on the frequency of HER2-positive cases among Brazilian patients are limited. Our aim was to characterize HER2 protein and gene status in a series of Brazilian patients with gastric cancer and to evaluate its association with clinicopathological data.

The malignant form of atrophic papulosis (Köhlmeier-Degos disease) is a rare thrombo-occlusive vasculopathy that can affect multiple organ systems. Patients typically present with distinctive skin lesions reflective of vascular drop out. The small bowel is the most common internal organ involved, resulting in considerable morbidity and mortality attributable to ischemic microperforations. Determination of the presence of gastrointestinal lesions is critical in distinguishing systemic from the benign, cutaneous only disease and in identifying candidates for treatment.

Magnifying endoscopy with narrow-band imaging (ME-NBI) is more reliable than chromoendoscopy (CE) for delineating the horizontal extent of early gastric cancers prior to endoscopic submucosal dissection (ESD). However, the added benefits of ME-NBI over CE in terms of the difference in magnification level have yet to be elucidated. The aim of this study was to investigate the improvement in diagnostic accuracy for tumor delineation obtained with different magnification levels of ME-NBI following CE.

Under conditions of inflammation in the absence of micro-organisms (sterile inflammation), necrotic cells release damage-associated molecular patterns that bind to Toll-like receptors on immune cells to activate a signaling pathway that involves activation of IκB kinase and nuclear factor κB (NF-κB). Little is known about the mechanisms that control NF-κB activity during sterile inflammation. We analyzed the contribution of B-cell CLL/lymphoma 3 (BCL3), a transcription factor that associates with NF-κB, in control of sterile inflammation in the pancreas and biliary system of mice.