Immune modulation in chronic hepatitis B patients

The hepatitis B virus (HBV) is a 42 nm viral particle and member of the hepadnaviridae family. Its double-shelled structure consists of an outer envelop composed of surface proteins (HBsAg) and an inner capsid formed by core-proteins (HBcAg) surrounding the partially double stranded DNA (1). The HBV DNA has 4, partially overlapping, open reading frames (ORF's) encoding for the viral antigens. ORF P is the longest one and has four contiguous regions: one encoding for the terminal protein (a covalently bound protein necessary for minus strand syntheses priming (primase)), a second non-specific domain (spacer), a third for the reverse transcriptase and a fourth domain encoding for RNaseH. ORF S encodes for the pre-S1, pre-S2 proteins and the HBs-antigen and is completely located within ORF P. In particular pre-S1 is suggested to be important for viral attachment (2). HBsAg contains the major antigenic a-determinant. HBsAg is produced at the membrane of the endoplasmic reticulum (ER): complete virions, the non-infectious filaments (containing small, middle and large HBsAg proteins) or spheres (consisting of small and middle-sized HBsAg proteins) circulate in serum in excess. ORF C encodes for the (pre-) core proteins, HBeAg and HBcAg. The core particles are postulated to be necessary for the assembly of the virus. HBcAg is synthesized in the cytosol and can be stored in the nucleus. In serum however, it is undetectable in contrast to the secretory form of the core protein, HBeAg. ORF X expresses the X-gene, the putative transcriptional activator of several genes. Both ORF C and ORF X partially overlap with ORF P (1)

Osteopenia and osteoporosis in Crohn's disease: prevalence in a Dutch population-based cohort

Reduced bone mineral density (BMD) has been reported in 3-77% of patients with inflammatory bowel disease (IBD). The majority of these studies are cross-sectional and from tertiary referral centres. The aim of our study was to estimate the prevalence of metabolic bone disease and of symptomatic fractures in a population of patients with Crohn's disease (CD) living in a well-defined geographic area. Patients with CD living in three adjacent municipalities within the IBD South-Limburg study area were investigated. BMD was measured by dual X-ray absorptiometry (DXA) of the femoral neck, lumbar spine and total body. The population comprised of 181 CD patients, 23 of whom were excluded. One-hundred-and-nineteen (75%) of the 158 eligible patients (37 males, 82 females with a mean age of 42 years (17-78)) were investigated. Osteopenia of lumbar spine and/or femoral neck was found in 45% of patients. Osteoporosis was found in another 13% of patients. Mean BMD (T-score) of femoral neck was significantly lower than of lumbar spine (P < 0.001). Male CD patients and patients aged under 18 at diagnosis are more at risk of having a low bone mass at the lumbar spine (P < 0.001) and total body (P = 0.018). The prevalence of osteoporosis in postmenopausal CD patients (29%) was significantly higher than in premenopausal patients (3%) (odds ratio: 12). Twenty-nine of 119 (24%) patients had a history of symptomatic fractures. Osteopenia and osteoporosis are frequent in CD and should have the full attention of the treating physician

Evaluation of polypectomy quality indicators of large nonpedunculated colorectal polyps in a nonexpert, bowel cancer screening cohort

Background and Aims: With the introduction of the national bowel cancer screening program, the detection of sessile and flat colonic lesions >= 20 mmin size, defined as large nonpedunculated colorectal polyps (LNPCPs), has increased. The aim of this study was to examine the quality of endoscopic treatment of LNPCPs in the Dutch screening program.Methods: This investigation comprised 2 related, but separate, substudies (1 with a cross-sectional design and 1 with a longitudinal design). The first examined prevalence and characteristics of LNPCPs in data from the national Dutch screening cohort from February 2014 until January 2017. The second, with screening data from 5 endoscopy units in the Southern part of the Netherlands from February 2014 until August 2015, examined performance on important quality indicators (technical and clinical successes, recurrence rate, adverse event rate, and surgery referral rate). All patients were part of the national Dutch screening cohort.Results: In the national cohort, an LNPCP was detected in 8% of participants. Technical and clinical success decreased with increasing LNPCP size, from 93% and 96% in 20- to 29-mm lesions to 85% and 86% in 30- to 39-mm lesions and to 74% and 81% in >= 40-mm lesions (P = 30-mm polyps. Endoscopic resection of large polyps could benefit from additional training, quality monitoring, and centralization either within or between centers

Temporal trends and variability of colonoscopy performance in a gastroenterology practice

Background and study aim: Quality measures for colonoscopy are operator dependent and vary. It is unclear whether quality measures change over time. In this study, time-dependent variation in colonoscopy performance was examined in a gastroenterology practice. Patients and methods: Colonoscopy and histopathology records that were collected at three hospitals (one university and two non-university hospitals) over three time periods (2007, 2010, and 2013) were reviewed. Data from colonoscopists performing at least 100 procedures per year were analyzed. Inter-colonoscopist variation in performance (i. e. adjusted cecal intubation rate [aCIR], adenoma detection rate [ADR], advanced ADR, mean adenomas per procedure [MAP], proximal ADR, nonpolypoid ADR, and serrated polyp detection rate) were examined using coefficients of variation. Logistic regression analyses were also performed, adjusting for covariates. Results: A total of 23 colonoscopists performing 6400 procedures were included. Overall, the mean aCIR, ADR, MAP, and proximal ADR improved significantly over time, from 91.9 %, 22.5 %, 0.37, and 10.2 % in 2007 to 95.3 %, 25.8 %, 0.45, and 13.4 %, respectively, in 2013 (P < 0.05). The inter-colonoscopist variation in ADR decreased from 37 % in 2007 to 15 % in 2013 (P < 0.05). In the non-university hospitals, mean values for quality measures increased significantly over time, whereas they remained stable in the university hospital. Conclusions: Variability in performance among colonoscopists decreased significantly within the gastroenterology clinical practice. Core quality measures improved over time, mainly through improvement of the lower performers. Measurement of inter-colonoscopist variation in performance helps to identify factors that stimulate or hinder performance, and forms the basis for interventions. TRIAL REGISTRATION: http://www.trialregister.nl