105 research outputs found
Oral serum-derived bovine immunoglobulin improves duodenal immune reconstitution and absorption function in patients with HIV enteropathy.
ObjectivesTo examine the impact of serum-derived bovine immunoglobulin, an oral medical food known to neutralize bacterial antigen and reduce intestinal inflammation, on restoration of mucosal immunity and gastrointestinal function in individuals with HIV enteropathy.DesignOpen-label trial with intensive 8-week phase of bovine serum immunoglobulin (SBI) 2.5āg twice daily with a 4-week washout period and an optional 9-month extension study.MethodsHIV enteropathy was defined as chronic gastrointestinal symptoms including frequent loose or watery stools despite no identifiable, reversible cause. Upper endoscopy for tissue immunofluorescent antibody assay and disaccharide gut permeability/absorption studies were performed before and after 8 weeks of SBI to test mucosal immunity and gastrointestinal function. Blood was collected for markers of microbial translocation, inflammation, and collagen kinetics. A validated gastrointestinal questionnaire assessed changes in symptoms.ResultsAll eight participants experienced profound improvement in symptoms with reduced bowel movements/day (Pā=ā0.008) and improvements in stool consistency (Pā=ā0.008). Gut permeability was normal before and after the intervention, but D-xylose absorption increased in seven of eight participants. Mucosal CD4 lymphocyte densities increased by a median of 139.5ācells/mm2 from 213 to 322ācells/mm2 (Pā=ā0.016). Intestinal-fatty acid binding protein (I-FABP), a marker of enterocyte damage, initially rose in seven of eight participants after 8 weeks (Pā=ā0.039), and then fell below baseline in four of five who continued receiving SBI (Pā=ā0.12). Baseline serum I-FABP levels were negatively correlated with subsequent rise in mucosal CD4 lymphocyte densities (rā=ā-0.74, Pā=ā0.046).ConclusionSBI significantly increases intestinal mucosal CD4 lymphocyte counts, improves duodenal function, and showed evidence of promoting intestinal repair in the setting of HIV enteropathy
Three-Tiered Risk Stratification Model to Predict Progression in Barrett's Esophagus Using Epigenetic and Clinical Features
Barrett's esophagus predisposes to esophageal adenocarcinoma. However, the value of endoscopic surveillance in Barrett's esophagus has been debated because of the low incidence of esophageal adenocarcinoma in Barrett's esophagus. Moreover, high inter-observer and sampling-dependent variation in the histologic staging of dysplasia make clinical risk assessment problematic. In this study, we developed a 3-tiered risk stratification strategy, based on systematically selected epigenetic and clinical parameters, to improve Barrett's esophagus surveillance efficiency
Interferon Gamma-Dependent Intestinal Pathology Contributes to the Lethality in Bacterial Superantigen-Induced Toxic Shock Syndrome
Toxic shock syndrome (TSS) caused by the superantigen exotoxins of Staphylococcus aureus and Streptococcus pyogenes is characterized by robust T cell activation, profound elevation in systemic levels of multiple cytokines, including interferon-Ī³ (IFN-Ī³), followed by multiple organ dysfunction and often death. As IFN-Ī³ possesses pro- as well as anti-inflammatory properties, we delineated its role in the pathogenesis of TSS. Antibody-mediated in vivo neutralization of IFN-Ī³ or targeted disruption of IFN-Ī³ gene conferred significant protection from lethal TSS in HLA-DR3 transgenic mice. Following systemic high dose SEB challenge, whereas the HLA-DR3.IFN-Ī³+/+ mice became sick and succumbed to TSS, HLA-DR3.IFN-Ī³ā/ā mice appeared healthy and were significantly protected from SEB-induced lethality. SEB-induced systemic cytokine storm was significantly blunted in HLA-DR3.IFN-Ī³ā/ā transgenic mice. Serum concentrations of several cytokines (IL-4, IL-10, IL-12p40 and IL-17) and chemokines (KC, rantes, eotaxin and MCP-1) were significantly lower in HLA-DR3.IFN-Ī³ā/ā transgenic mice. However, SEB-induced T cell expansion in the spleens was unaffected and expansion of SEB-reactive TCR VĪ²8+ CD4+ and CD8+ T cells was even more pronounced in HLA-DR3.IFN-Ī³ā/ā transgenic mice when compared to HLA-DR3.IFN-Ī³+/+ mice. A systematic histopathological examination of several vital organs revealed that both HLA-DR3.IFN-Ī³+/+ and HLA-DR3.IFN-Ī³ā/ā transgenic mice displayed comparable severe inflammatory changes in lungs, and liver during TSS. Remarkably, whereas the small intestines from HLA-DR3.IFN-Ī³+/+ transgenic mice displayed significant pathological changes during TSS, the architecture of small intestines in HLA-DR3.IFN-Ī³ā/ā transgenic mice was preserved. In concordance with these histopathological changes, the gut permeability to macromolecules was dramatically increased in HLA-DR3.IFN-Ī³+/+ but not HLA-DR3.IFN-Ī³ā/ā mice during TSS. Overall, IFN-Ī³ seemed to play a lethal role in the immunopathogenesis of TSS by inflicting fatal small bowel pathology. Our study thus identifies the important role for IFN-Ī³ in TSS
ŠŠøŃŠŗŃŃŃŃ ŠæŃŠ¾ ŠæŠµŃŃŠæŠµŠŗŃŠøŠ²Šø Š·Š°ŠæŃŠ¾Š²Š°Š“Š¶ŠµŠ½Š½Ń Š¼ŃŃŃŠŗŠ¾Ń ŃŠµŃŠ¾ŃŠ¼Šø 1870 ŃŠ¾ŠŗŃ Ń ŠŃŠøŠ¼Ń
We carried out a trans-ancestry genome-wide association and replication study of blood pressure phenotypes among up to 320,251 individuals of East Asian, European and South Asian ancestry. We find genetic variants at 12 new loci to be associated with blood pressure (P = 3.9 x 10(-11) to 5.0 x 10(-21)). The sentinel blood pressure SNPs are enriched for association with DNA methylation at multiple nearby CpG sites, suggesting that, at some of the loci identified, DNA methylation may lie on the regulatory pathway linking sequence variation to blood pressure. The sentinel SNPs at the 12 new loci point to genes involved in vascular smooth muscle (IGFBP3, KCNK3, PDE3A and PRDM6) and renal (ARHGAP24, OSR1, SLC22A7 and TBX2) function. The new and known genetic variants predict increased left ventricular mass, circulating levels of NT-proBNP, and cardiovascular and all-cause mortality (P = 0.04 to 8.6 x 10(-6)). Our results provide new evidence for the role of DNA methylation in blood pressure regulation
Development and Validation of a Symptom-Based Activity Index for Adults With Eosinophilic Esophagitis
Standardized instruments are needed to assess the activity of eosinophilic esophagitis (EoE), to provide endpoints for clinical trials and observational studies. We aimed to develop and validate a patient-reported outcome (PRO) instrument and score, based on items that could account for variations in patientsā assessments of disease severity. We also evaluated relationships between patientsā assessment of disease severity and EoE-associated endoscopic, histologic, and laboratory findings
Chronic persistent infection andpol gene expression by duck hepatitis B virus
Hepadnaviruses can cause not only acute but also chronic infections. The regulation of the copy number of the viral transcriptional template, covalently closed circular (CCC) DNA, is believed to play an important role in maintenance of chronic infections. To distinguish between an intracellular and an extracellular pathway for DHBV CCC DNA amplification in infected primary duck hepatocyte cultures, we employed anti-viral agents to block the extracellular route. We found that CCC DNA amplification still occurred when the extracellular reinfection pathway was blocked. This result indicates that CCC DNA amplification in chronically infected cultures and by inference, the maintenance of persistent infection, involves primarily an intracellular regulatory pathway. The role of viral polymerase and precore proteins in CCC DNA amplification was next investigated by genetic analysis. DHBV with a mutated genome was produced by transfection of LMH cells with cloned DHBV DNAs, and was used to infect primary duck hepatocytes. Our results provided genetic evidence that CCC DNA is synthesized by the viral polymerase and that precore is not essential for CCC DNA amplification in hepatocyte cultures. The synthesis of CCC DNA was also studied in LMH sublines stably-transformed with DHBV DNAs. An LMH subline (D2) stably-transformed with wild-type DHBV, accumulated a large amount of CCC DNA (30-50 copies per cell), just as the chronically infected liver does. A similar level of CCC DNA synthesis was observed in an LMH subline (1S-5) stably-transformed with a DHBV envelope mutant. The mechanisms by which less-than-full-length pol gene products are produced and their role in viral replication are not clear. We introduced frameshift or stop codon insertion mutations in the spacer region of the DHBV pol gene to address this problem. Our results demonstrated a leaky viral DNA synthesis phenotype. The leakiness of most of these mutants appeared to attributable to translational suppression. However, the +2 frameshift mutants appeared to use a novel way to express the viral pol gene, by synthesizing the viral reverse transcriptase as a fusion protein with the amino-terminal portion of preS protein. This result implies that less-than-full-length pol gene products are functional in viral DNA synthesis
Advances in biomedical research The Sixth Annual Joint Scientific Symposium of NIH/FDA CAA and Washington DC Chapter of SCBA
555 Association of Autophagy Regulator Beclin 1 With Response to Neoadjuvant Chemoradiation in Rectal Carcinoma
Su1113 ā Risk Factors, Endoscopic Features, and Clinical Outcomes of Cytomegalovirus Esophagitis: A Single Center 10-Year Experience
- ā¦