Does nasal colonization with Methicillin-resistant Staphylococcus aureus (MRSA) in pig farmers persist after holidays from pig exposure?

In Germany, it has been reported that up to 86% of pig farmers are colonized with Methicillin-resistant Staphylococcus aureus (MRSA) in the nares, at least intermittently. However, little is known about the long-term persistence of colonization, especially when the farmers do not have daily contact to pigs. Here, we analyzed whether an absence from work during the summer holidays had an impact on nasal MRSA colonization rates of pig farmers

Ketosis risk derived from mid-infrared predicted traits and its relationship with herd milk yield, health and fertility

Milk analysis using mid-infrared spectroscopy (MIR) is a fast and inexpensive way of examining milk samples on a large scale for fat, protein, lactose, urea and many other novel traits. A new indicator trait for ketosis, KetoMIR, which is based on clinical ketosis diagnoses and MIR-predicted traits, was developed by the Regional State Association for Performance and Quality Inspection in Animal Breeding of Baden Württemberg in 2015. The KetoMIR result is available for each cow at milk recording during the first 120 days in milk and presented to farmers in three classes: 1 = low ketosis risk, 2 = moderate ketosis risk and 3 = high ketosis risk. The aim of the current study was to analyze the phenotypic relationships between KetoMIR and milk yield, fertility and health at the herd level. Annual herd reports from 12,909 herds with an average herd size of 27 cows were available for the analyses. Overall, the mean incidence of ketosis (KetoMIR risk class 2 or 3) at the herd level was 14.0%. Farms with the lowest ketosis risk (≤10% of cows in the herd with a moderate or high ketosis risk) differed in all variables from the farms with the highest ketosis risk (>50% of cows in the herd with a moderate or high ketosis risk). The increased ketosis risk based on KetoMIR was associated with lower average herd milk yield (-1,975 kg milk). Mean herd somatic cell count in first and higher lactations was increased by 60,500 and 134,400 cells/ml, respectively. The interval from calving to first service was prolonged by +36.5 days, as was the calving interval with +58.2 days. The newly developed KetoMIR trait may be used in ketosis prevention programs

Dynamics in Liver Stiffness Measurements Predict Outcomes in Advanced Chronic Liver Disease

Background &amp; Aims:Liver stiffness measurements (LSMs) provide an opportunity to monitor liver disease progression and regression noninvasively. We aimed to determine the prognostic relevance of LSM dynamics over time for liver-related events and death in patients with chronic liver disease. Methods:Patients with chronic liver disease undergoing 2 or more reliable LSMs at least 180 days apart were included in this retrospective cohort study and stratified at baseline (BL) as nonadvanced chronic liver disease (non-ACLD, BL-LSM &lt; 10 kPa), compensated ACLD (cACLD; BL-LSM ≥ 10 kPa), and decompensated ACLD. Data on all consecutive LSMs and clinical outcomes were collected. Results: There were 2508 patients with 8561 reliable LSMs (3 per patient; interquartile range, 2–4) included: 1647 (65.7%) with non-ACLD, 757 (30.2%) with cACLD, and 104 (4.1%) with decompensated ACLD. Seven non-ACLD patients (0.4%) and 83 patients with cACLD (10.9%) developed hepatic decompensation (median follow-up, 71 months). A 20% increase in LSM at any time was associated with an approximately 50% increased risk of hepatic decompensation (hazard ratio, 1.58; 95% CI, 1.41–1.79; P &lt;.001) and liver-related death (hazard ratio, 1.45; 95% CI, 1.28–1.68; P &lt;.001) in patients with cACLD. LSM dynamics yielded a high accuracy to predict hepatic decompensation in the following 12 months (area under the receiver operating characteristics curve = 0.933). The performance of LSM dynamics was numerically better than dynamics in Fibrosis-4 score (0.873), Model for End-Stage Liver Disease (0.835), and single time-point LSM (BL-LSM: 0.846; second LSM: 0.880). Any LSM decrease to &lt;20 kPa identified patients with cACLD with a substantially lower risk of hepatic decompensation (hazard ratio, 0.13; 95% CI, 0.07–0.24). If reliable, LSM also confers prognostic information in decompensated ACLD. Conclusions: Repeating LSM enables an individual and updated risk assessment for decompensation and liver-related mortality in ACLD.</p

Generation of Covalently Closed Circular DNA of Hepatitis B Viruses via Intracellular Recycling Is Regulated in a Virus Specific Manner

Persistence of hepatitis B virus (HBV) infection requires covalently closed circular (ccc)DNA formation and amplification, which can occur via intracellular recycling of the viral polymerase-linked relaxed circular (rc) DNA genomes present in virions. Here we reveal a fundamental difference between HBV and the related duck hepatitis B virus (DHBV) in the recycling mechanism. Direct comparison of HBV and DHBV cccDNA amplification in cross-species transfection experiments showed that, in the same human cell background, DHBV but not HBV rcDNA converts efficiently into cccDNA. By characterizing the distinct forms of HBV and DHBV rcDNA accumulating in the cells we find that nuclear import, complete versus partial release from the capsid and complete versus partial removal of the covalently bound polymerase contribute to limiting HBV cccDNA formation; particularly, we identify genome region-selectively opened nuclear capsids as a putative novel HBV uncoating intermediate. However, the presence in the nucleus of around 40% of completely uncoated rcDNA that lacks most if not all of the covalently bound protein strongly suggests a major block further downstream that operates in the HBV but not DHBV recycling pathway. In summary, our results uncover an unexpected contribution of the virus to cccDNA formation that might help to better understand the persistence of HBV infection. Moreover, efficient DHBV cccDNA formation in human hepatoma cells should greatly facilitate experimental identification, and possibly inhibition, of the human cell factors involved in the process

Human Hepatitis B Virus Production in Avian Cells Is Characterized by Enhanced RNA Splicing and the Presence of Capsids Containing Shortened Genomes

Experimental studies on hepatitis B virus (HBV) replication are commonly done with human hepatoma cells to reflect the natural species and tissue tropism of the virus. However, HBV can also replicate, upon transfection of virus coding plasmids, in cells of other species. In such cross-species transfection experiments with chicken LMH hepatoma cells, we previously observed the formation of HBV genomes with aberrant electrophoretic mobility, in addition to the those DNA species commonly seen in human HepG2 hepatoma cells. Here, we report that these aberrant DNA forms are mainly due to excessive splicing of HBV pregenomic RNA and the abundant synthesis of spliced DNA products, equivalent to those also made in human cells, yet at much lower level. Mutation of the common splice acceptor site abolished splicing and in turn enhanced production of DNA from full-length pgRNA in transfected LMH cells. The absence of splicing made other DNA molecules visible, that were shortened due to the lack of sequences in the core protein coding region. Furthermore, there was nearly full-length DNA in the cytoplasm of LMH cells that was not protected in viral capsids. Remarkably, we have previously observed similar shortened genomes and non-protected viral DNA in human HepG2 cells, yet exclusively in the nucleus where uncoating and final release of viral genomes occurs. Hence, two effects reflecting capsid disassembly in the nucleus in human HepG2 cells are seen in the cytoplasm of chicken LMH cells

Does nasal colonization with Methicillin-resistant Staphylococcus aureus (MRSA) in pig farmers persist after holidays from pig exposure?

In Germany, it has been reported that up to 86% of pig farmers are colonized with Methicillin-resistant Staphylococcus aureus (MRSA) in the nares, at least intermittently. However, little is known about the long-term persistence of colonization, especially when the farmers do not have daily contact to pigs. Here, we analyzed whether an absence from work during the summer holidays had an impact on nasal MRSA colonization rates of pig farmers.</p

Hepatitis B Virus Nucleocapsids Formed by Carboxy-Terminally Mutated Core Proteins Contain Spliced Viral Genomes but Lack Full-Size DNA

The carboxy-terminal sequence of the hepatitis B virus (HBV) core protein constitutes a nucleic acid binding domain that is rich in arginine residues and contains three serine phosphorylation sites. While dispensable for capsid assembly, this domain is involved in viral replication, as demonstrated by the effects of mutations on RNA packaging and/or reverse transcription; however, the underlying mechanisms are poorly understood. Here we tested a series of core protein mutants in which the three serine phosphorylation sites were replaced by glutamic acid, in parallel with a previously described deletion variant lacking the 19 C-terminal amino acid residues, for their ability to support viral replication in transfected hepatoma cells. Replacement of all serines and the deletion gave rise to nucleocapsids containing a smaller than wild-type DNA genome. Rather than a single-stranded DNA intermediate, as previously thought, this was a 2.0-kbp double-stranded DNA molecule derived from spliced pregenomic RNA (pgRNA). Interestingly, full-length pgRNA was associated with nucleocapsids but was found to be sensitive to nuclease digestion, while encapsidated spliced RNA and 3′ truncated RNA species were nuclease resistant. These findings suggest that HBV pgRNA encapsidation is directional and that a packaging limit is determined by the C-terminal portion of the core protein