Congenital Cytomegalovirus Infection: A Narrative Review of the Issues in Screening and Management From a Panel of European Experts.

Maternal primary and non-primary cytomegalovirus (CMV) infection during pregnancy can result in in utero transmission to the developing fetus. Congenital CMV (cCMV) can result in significant morbidity, mortality or long-term sequelae, including sensorineural hearing loss, the most common sequela. As a leading cause of congenital infections worldwide, cCMV infection meets many of the criteria for screening. However, currently there are no universal programs that offer maternal or neonatal screening to identify infected mothers and infants, no vaccines to prevent infection, and no efficacious and safe therapies available for the treatment of maternal or fetal CMV infection. Data has shown that there are several maternal and neonatal screening strategies, and diagnostic methodologies, that allow the identification of those at risk of developing sequelae and adequately detect cCMV. Nevertheless, many questions remain unanswered in this field. Well-designed clinical trials to address several facets of CMV treatment (in pregnant women, CMV-infected fetuses and both symptomatic and asymptomatic neonates and children) are required. Prevention (vaccines), biology and transmission factors associated with non-primary CMV, and the cost-effectiveness of universal screening, all demand further exploration to fully realize the ultimate goal of preventing cCMV. In the meantime, prevention of primary infection during pregnancy should be championed to all by means of hygiene education

HIV-1 Envelope Subregion Length Variation during Disease Progression

The V3 loop of the HIV-1 Env protein is the primary determinant of viral coreceptor usage, whereas the V1V2 loop region is thought to influence coreceptor binding and participate in shielding of neutralization-sensitive regions of the Env glycoprotein gp120 from antibody responses. The functional properties and antigenicity of V1V2 are influenced by changes in amino acid sequence, sequence length and patterns of N-linked glycosylation. However, how these polymorphisms relate to HIV pathogenesis is not fully understood. We examined 5185 HIV-1 gp120 nucleotide sequence fragments and clinical data from 154 individuals (152 were infected with HIV-1 Subtype B). Sequences were aligned, translated, manually edited and separated into V1V2, C2, V3, C3, V4, C4 and V5 subregions. V1-V5 and subregion lengths were calculated, and potential N-linked glycosylation sites (PNLGS) counted. Loop lengths and PNLGS were examined as a function of time since infection, CD4 count, viral load, and calendar year in cross-sectional and longitudinal analyses. V1V2 length and PNLGS increased significantly through chronic infection before declining in late-stage infection. In cross-sectional analyses, V1V2 length also increased by calendar year between 1984 and 2004 in subjects with early and mid-stage illness. Our observations suggest that there is little selection for loop length at the time of transmission; following infection, HIV-1 adapts to host immune responses through increased V1V2 length and/or addition of carbohydrate moieties at N-linked glycosylation sites. V1V2 shortening during early and late-stage infection may reflect ineffective host immunity. Transmission from donors with chronic illness may have caused the modest increase in V1V2 length observed during the course of the pandemic

Structure of Parvovirus B19 Decorated by Fabs from a Human Antibody

Parvovirus B19, one of the most common human pathogens, is a small DNA virus that belongs to the Parvoviridae. As a result of previous infections, antibodies to B19 are present in most adults. B19 has a strong tropism to erythroid progenitor cells and is able to cause a series of medical conditions, including fifth disease, arthritis, myocarditis, hydrops fetalis, and aplastic crisis. No approved vaccine is currently available for B19, and there is a lack of structural characterization of any B19 epitopes. Here we present the first cryo-electron microscopy (cryo-EM) structure of a B19 virus-like particle (VLP) complexed with the antigen-binding fragment (Fab) of a human neutralizing antibody, 860-55D. A model was built into the 3.2-angstrom-resolution map, and the antigenic residues on the surface of the B19 capsid were identified. Antibody 860-55D bridges the capsid of B19 by binding to a quaternary structure epitope formed by residues from three neighboring VP2 capsid proteins. IMPORTANCE Parvovirus B19 is a common human pathogen and a particular threat to children, pregnant women, and patients with sickle cell disease or AIDS. Currently, neutralizing antibody is the most efficient treatment for acute B19 infections. Research on the antigenic properties of B19 will guide the usage of these antibodies and facilitate vaccine development. We have determined and report here the high-resolution structure of B19 virus-like particles (VLPs) complexed with the Fab of a human neutralizing antibody. The structure shows a quaternary structure epitope formed by three VP2 proteins and provides details on host recognition of human B19 virus

Multi-scale electrolyte transport simulations for lithium ion batteries

Establishing a link between atomistic processes and battery cell behavior is a major challenge for lithium ion batteries. Focusing on liquid electrolytes, we describe parameter-free molecular dynamics predictions of their mass and charge transport properties. The simulations agree quantitatively with experiments across the full range of relevant ion concentrations and for different electrolyte compositions. We introduce a simple analytic form to describe the transport properties. Our results are used in an extended Newman electrochemical model, including a cell temperature prediction. This cross-scale approach provides quantitative agreement between calculated and measured discharge voltage of a battery and enables the computational optimization of the electrolyte formulation.Note that the project involved/was led by authors with addresses at Dassault Systèmes and used their BIOVIA Materials Studio. - EPSRC Centre for Doctoral Training for Computational Methods for Materials Science (EP/L015552/1). - Faraday Institution (EP/S003053/1)

Multi-scale electrolyte transport simulations for lithium ion batteries

Establishing a link between atomistic processes and battery cell behavior is a major challenge for lithium ion batteries. Focusing on liquid electrolytes, we describe parameter-free molecular dynamics predictions of their mass and charge transport properties. The simulations agree quantitatively with experiments across the full range of relevant ion concentrations and for different electrolyte compositions. We introduce a simple analytic form to describe the transport properties. Our results are used in an extended Newman electrochemical model, including a cell temperature prediction. This cross-scale approach provides quantitative agreement between calculated and measured discharge voltage of a battery and enables the computational optimization of the electrolyte formulation

Multi-scale electrolyte transport simulations for lithium ion batteries

Establishing a link between atomistic processes and battery cell behavior is a major challenge for lithium ion batteries. Focusing on liquid electrolytes, we describe parameter-free molecular dynamics predictions of their mass and charge transport properties. The simulations agree quantitatively with experiments across the full range of relevant ion concentrations and for different electrolyte compositions. We introduce a simple analytic form to describe the transport properties. Our results are used in an extended Newman electrochemical model, including a cell temperature prediction. This cross-scale approach provides quantitative agreement between calculated and measured discharge voltage of a battery and enables the computational optimization of the electrolyte formulation.Note that the project involved/was led by authors with addresses at Dassault Systèmes and used their BIOVIA Materials Studio. - EPSRC Centre for Doctoral Training for Computational Methods for Materials Science (EP/L015552/1). - Faraday Institution (EP/S003053/1)