Inflammation, cytomegalovirus and the growth hormone axis in HIV-exposed uninfected Zimbabwean infants.

Objectives: Despite avoiding HIV infection, HIV-exposed uninfected (HEU) infants have poorer clinical outcomes than HIV-unexposed infants, including impaired growth. The growth hormone (GH) axis is an important regulator of infant growth through hepatic synthesis of insulin-like growth-factor-1 (IGF-1), and may be disrupted by chronic inflammation and acute infections, including cytomegalovirus (CMV). We tested the hypothesis that these factors lead to disruption of the GH axis in HEU infants, which might contribute to their impaired growth.

Bonamia exitiosa in farmed native oysters Ostrea angasi in Australia: optimal epidemiological qPCR cut-point and clinical disease risk factors.

Bonamiosis has developed as a problem in Australian native oysters Ostrea angasi since the parasite Bonamia spp. was first detected in Port Phillip Bay, Victoria, in the early 1990s. At that time, large-scale mortalities in both farmed and wild oysters saw the demise of the pilot native oyster culture industry.

Fast, Rate-Independent, Finite Element Implementation of a 3D Constrained Mixture Model of Soft Tissue Growth and Remodeling.

Constrained mixture models of soft tissue growth and remodeling can simulate many evolving conditions in health as well as in disease and its treatment, but they can be computationally expensive. In this paper, we derive a new fast, robust finite element implementation based on a concept of mechanobiological equilibrium that yields fully resolved solutions and allows computation of quasi-equilibrated evolutions when imposed perturbations are slow relative to the adaptive process. We demonstrate quadratic convergence and verify the model via comparisons with semi-analytical solutions for arterial mechanics.

Multimodality Imaging-Based Characterization of Regional Material Properties in a Murine Model of Aortic Dissection.

Chronic infusion of angiotensin-II in atheroprone (ApoE) mice provides a reproducible model of dissection in the suprarenal abdominal aorta, often with a false lumen and intramural thrombus that thickens the wall. Such lesions exhibit complex morphologies, with different regions characterized by localized changes in wall composition, microstructure, and properties. We sought to quantify the multiaxial mechanical properties of murine dissecting aneurysm samples by combining in vitro extension-distension data with full-field multimodality measurements of wall strain and thickness to inform an inverse material characterization using the virtual fields method.

FUS ALS-causative mutations impair FUS autoregulation and splicing factor networks through intron retention.

Mutations in the RNA-binding protein FUS cause amyotrophic lateral sclerosis (ALS), a devastating neurodegenerative disease. FUS plays a role in numerous aspects of RNA metabolism, including mRNA splicing. However, the impact of ALS-causative mutations on splicing has not been fully characterized, as most disease models have been based on overexpressing mutant FUS, which will alter RNA processing due to FUS autoregulation.

Paradoxical aortic stiffening and subsequent cardiac dysfunction in Hutchinson-Gilford progeria syndrome.

Hutchinson-Gilford progeria syndrome (HGPS) is an ultra-rare disorder with devastating sequelae resulting in early death, presently thought to stem primarily from cardiovascular events. We analyse novel longitudinal cardiovascular data from a mouse model of HGPS () using allometric scaling, biomechanical phenotyping, and advanced computational modelling and show that late-stage diastolic dysfunction, with preserved systolic function, emerges with an increase in the pulse wave velocity and an associated loss of aortic function, independent of sex. Specifically, there is a dramatic late-stage loss of smooth muscle function and cells and an excessive accumulation of proteoglycans along the aorta, which result in a loss of biomechanical function (contractility and elastic energy storage) and a marked structural stiffening despite a distinctly low intrinsic material stiffness that is consistent with the lack of functional lamin A.

A three-dimensional phase-field model for multiscale modeling of thrombus biomechanics in blood vessels.

Mechanical interactions between flowing and coagulated blood (thrombus) are crucial in dictating the deformation and remodeling of a thrombus after its formation in hemostasis. We propose a fully-Eulerian, three-dimensional, phase-field model of thrombus that is calibrated with existing in vitro experimental data. This phase-field model considers spatial variations in permeability and material properties within a single unified mathematical framework derived from an energy perspective, thereby allowing us to study effects of thrombus microstructure and properties on its deformation and possible release of emboli under different hemodynamic conditions.

Smooth Muscle Cell Reprogramming in Aortic Aneurysms.

The etiology of aortic aneurysms is poorly understood, but it is associated with atherosclerosis, hypercholesterolemia, and abnormal transforming growth factor β (TGF-β) signaling in smooth muscle. Here, we investigated the interactions between these different factors in aortic aneurysm development and identified a key role for smooth muscle cell (SMC) reprogramming into a mesenchymal stem cell (MSC)-like state. SMC-specific ablation of TGF-β signaling in Apoe mice on a hypercholesterolemic diet led to development of aortic aneurysms exhibiting all the features of human disease, which was associated with transdifferentiation of a subset of contractile SMCs into an MSC-like intermediate state that generated osteoblasts, chondrocytes, adipocytes, and macrophages.

Spontaneous reversal of stenosis in tissue-engineered vascular grafts.

We developed a tissue-engineered vascular graft (TEVG) for use in children and present results of a U.S. Food and Drug Administration (FDA)-approved clinical trial evaluating this graft in patients with single-ventricle cardiac anomalies.

A computational bio-chemo-mechanical model of in vivo tissue-engineered vascular graft development.

Stenosis is the primary complication of current tissue-engineered vascular grafts used in pediatric congenital cardiac surgery. Murine models provide considerable insight into the possible mechanisms underlying this situation, but they are not efficient for identifying optimal changes in scaffold design or therapeutic strategies to prevent narrowing. In contrast, computational modeling promises to enable time- and cost-efficient examinations of factors leading to narrowing.

5-Aryltetrazoles from Direct C-H Arylation with Aryl Bromides.

A mild, direct C-H arylation of 1-substituted tetrazoles to 5-aryltetrazoles is developed using a Pd/Cu cocatalytic system with readily available aryl bromides. The methodology avoids late-stage usage of azides and tolerates a wide range of functionalities.

Effects of improved complementary feeding and improved water, sanitation and hygiene on early child development among HIV-exposed children: substudy of a cluster randomised trial in rural Zimbabwe.

Introduction: HIV-exposed uninfected children may be at risk of poor neurodevelopment. We aimed to test the impact of improved infant and young child feeding (IYCF) and improved water, sanitation and hygiene (WASH) on early child development (ECD) outcomes.

Methods: Sanitation Hygiene Infant Nutrition Efficacy was a cluster randomised 2×2 factorial trial in rural Zimbabwe ClinicalTrials.

Predictors of oral rotavirus vaccine immunogenicity in rural Zimbabwean infants.

Background: Oral rotavirus vaccines (RVV) have poor immunogenicity in low-income countries, for reasons that remain unclear. This study identified the determinants of RVV immunogenicity among infants in rural Zimbabwe.

Methods: Anti-rotavirus IgA titres were measured among a sub-group of infants enrolled in the Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial (NCT01824940).

The Costs of Close Contacts: Visualizing the Energy Landscape of Cell Contacts at the Nanoscale.

Cell-cell contacts often underpin signaling between cells. For immunology, the binding of a T cell receptor to an antigen-presenting pMHC initiates downstream signaling and an immune response. Although this contact is mediated by proteins on both cells creating interfaces with gap sizes typically around 14 nm, many, often contradictory observations have been made regarding the influence of the contact on parameters such as the binding kinetics, spatial distribution, and diffusion of signaling proteins within the contact.

Aortic remodeling is modest and sex-independent in mice when hypertension is superimposed on aging.

Objectives: Increased central artery stiffness associates with cardiovascular disease. Among other factors, hypertension and aging are strong contributors to central artery stiffening, yet it has been difficult to separate their effects. Herein, we study isolated and combined effects of hypertension and aging on central artery remodeling in multiple mouse models as a function of sex.

Effects of improved water, sanitation, and hygiene and improved complementary feeding on environmental enteric dysfunction in children in rural Zimbabwe: A cluster-randomized controlled trial.

Background: Environmental enteric dysfunction (EED) may be an important modifiable cause of child stunting. We described the evolution of EED biomarkers from birth to 18 months in rural Zimbabwe and tested the independent and combined effects of improved water, sanitation, and hygiene (WASH), and improved infant and young child feeding (IYCF), on EED.

Methodology And Findings: The Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial was a 2x2 factorial cluster-randomised trial of improved IYCF and improved WASH on child stunting and anaemia at 18 months of age.

Chronic mTOR activation induces a degradative smooth muscle cell phenotype.

Smooth muscle cell (SMC) proliferation has been thought to limit the progression of thoracic aortic aneurysm and dissection (TAAD) because loss of medial cells associates with advanced disease. We investigated effects of SMC proliferation in the aortic media by conditional disruption of Tsc1, which hyperactivates mTOR complex 1. Consequent SMC hyperplasia led to progressive medial degeneration and TAAD.

Active site manipulation in MoS cluster electrocatalysts by transition metal doping.

The development of non-platinum group metal catalysts for the hydrogen evolution reaction (HER) in water electrolyser devices is essential for their widespread and sustainable deployment. In recent years, molybdenum disulfide (MoS2) catalysts have received significant attention as they not only exhibit good electrocatalytic HER activity but also, crucially, acid-stability. However, further performance enhancement is required for these materials to be competitive with Pt and to that end transition metal doping of MoS2 has been explored as a route to further increasing its catalytic activity.

Mortality Among People With HIV Treated for Tuberculosis Based on Positive, Negative, or No Bacteriologic Test Results for Tuberculosis: The IeDEA Consortium.

Background: In resource-constrained settings, many people with HIV (PWH) are treated for tuberculosis (TB) without bacteriologic testing. Their mortality compared with those with bacteriologic testing is uncertain.

Methods: We conducted an observational cohort study among PWH ≥15 years of age initiating TB treatment at sites affiliated with 4 International epidemiology Databases to Evaluate AIDS consortium regions from 2012 to 2014: Caribbean, Central and South America, and Central, East, and West Africa.

Computer-Controlled Biaxial Bioreactor for Investigating Cell-Mediated Homeostasis in Tissue Equivalents.

Soft biological tissues consist of cells and extracellular matrix (ECM), a network of diverse proteins, glycoproteins, and glycosaminoglycans that surround the cells. The cells actively sense the surrounding ECM and regulate its mechanical state. Cell-seeded collagen or fibrin gels, so-called tissue equivalents, are simple but powerful model systems to study this phenomenon.

Summarizing the Child Growth and Diarrhea Findings of the Water, Sanitation, and Hygiene Benefits and Sanitation Hygiene Infant Nutrition Efficacy Trials.

Stunting is a prevalent form of child undernutrition and is associated with lifelong adverse health outcomes and loss of human capital. The Water, Sanitation, and Hygiene (WASH) Benefits (Bangladesh and Kenya) and Sanitation Hygiene Infant Nutrition Efficacy (SHINE; Zimbabwe) trials were conducted to test the independent and combined effects of improved household WASH (improved pit latrine, handwashing station not connected to a water source, point-of-use water chlorination) and improved infant and young child feeding (IYCF, complementary feeding counseling and daily small-quantity lipid nutrient supplement) on child linear growth. Together the trials enrolled >19,000 women during pregnancy and measured >15,000 of their children at 18 months (SHINE) or 24 months (WASH Benefits trials) of age.

Mortality, Human Immunodeficiency Virus (HIV) Transmission, and Growth in Children Exposed to HIV in Rural Zimbabwe.

Background: Clinical outcomes of children who are human immunodeficiency virus (HIV)-exposed in sub-Saharan Africa remain uncertain.

Methods: The Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial evaluated improved infant and young child feeding (IYCF) and/or improved water, sanitation, and hygiene in 2 rural Zimbabwean districts with 15% antenatal HIV prevalence and > 80% prevention of mother-to-child transmission (PMTCT) coverage. Children born between February 2013 and December 2015 had longitudinal HIV testing and anthropometry.