Delivery of an injectable biomaterial to the striatum- a computational analysis

The delivery of a cell-embedded hydrogel to the striatum is a promising strategy for Parkinson’s disease.In this study, a computational model of the intrastriatal injection was used to analyze the delivery process

Ramp Up for Research Days : On-Campus + Online = Success

During fall 2015, Himmelfarb Library and The George Washington University Office of the Vice President for Research (OVPR) collaborated to increase health sciences student participation in GW’s annual Research Days event. The library launched two new initiatives designed to target both on-campus students and Distance Education (DE) students: six “Ramp Up to Research Days” workshops with both in-class and WebEx components, and a customized Research Days portal within the Health Sciences Research Commons (HSRC) digital repository

Are State-of-the-art Visual Place Recognition Techniques any Good for Aerial Robotics?

Visual Place Recognition (VPR) has seen significant advances at the frontiers of matching performance and computational superiority over the past few years. However, these evaluations are performed for ground-based mobile platforms and cannot be generalized to aerial platforms. The degree of viewpoint variation experienced by aerial robots is complex, with their processing power and on-board memory limited by payload size and battery ratings. Therefore, in this paper, we collect $8$ state-of-the-art VPR techniques that have been previously evaluated for ground-based platforms and compare them on $2$ recently proposed aerial place recognition datasets with three prime focuses: a) Matching performance b) Processing power consumption c) Projected memory requirements. This gives a birds-eye view of the applicability of contemporary VPR research to aerial robotics and lays down the the nature of challenges for aerial-VPR

Seasonal and spatial dynamics of enteric viruses in wastewater and in riverine and estuarine receiving waters

Enteric viruses represent a global public health threat and are implicated in numerous foodborne and waterborne disease outbreaks. Nonetheless, relatively little is known of their fate and stability in the environment. In this study we used carefully validated methods to monitor enteric viruses, namely adenovirus (AdV), JC polyomavirus (JCV), noroviruses (NoVs), sapovirus (SaV) and hepatitis A and E viruses (HAV and HEV) from wastewater source to beaches and shellfish beds. Wastewater influent and effluent, surface water, sediment and shellfish samples were collected in the Conwy catchment (North Wales, UK) once a month for one year. High concentrations of AdV and JCV were found in the majority of samples, and no seasonal patterns were observed. No HAV and HEV were detected and no related illnesses were reported in the area during the period of sampling. Noroviruses and SaV were also detected at high concentrations in wastewater and surface water, and their presence correlated with local gastroenteritis outbreaks during the spring and autumn seasons. Noroviruses were also found in estuarine sediment and in shellfish harvested for human consumption. As PCR-based methods were used for quantification, viral infectivity and degradation was estimated using a NoV capsid integrity assay. The assay revealed low-levels of viral decay in wastewater effluent compared to influent, and more significant decay in environmental waters and sediment. Results suggest that AdV and JCV may be suitable markers for the assessment of the spatial distribution of wastewater contamination in the environment; and pathogenic viruses can be directly monitored during and after reported outbreaks to prevent further environment-derived illnesses

Evaluation of Two Triplex One-Step qRT-PCR Assays for the Quantification of Human Enteric Viruses in Environmental Samples

Articles not assigned to an issueInternational audienceHuman enteric viruses are responsible for waterborne and shellfish-associated disease outbreaks worldwide. Quantitative reverse transcription PCR (qRT-PCR) is often used to assess the health risks associated with shellfish and environmental water, but viral titres in sediments are less commonly investigated. In this study, we developed and validated two multiplex qRT-PCR assays for aquatic sediment and shellfish samples targeting viruses that are a common cause of gastroenteritis (norovirus GI, GII and hepatitis A virus), two emerging viruses (sapovirus and hepatitis E virus), along with mengovirus (MgV), which is often used as a sample process control for the assessment of RNA extraction efficiency. Singleplex and multiplex assays demonstrated comparable PCR efficiencies and gave reliable results over a wide concentration range. The multiplex assays showed remarkable sensitivity with a limit of detection of 1 RNA copy/µL nucleic acid extract for all target viruses and limits of quantification of 3-18 RNA copies/µL for the targeted human pathogenic viruses and 20-40 RNA copies/µL for MgV. The results demonstrated the veracity of multiplex qRT-PCR for the estimation of viral titres in sediment and shellfish, allowing the rapid assessment of viral infection risks associated with environments exposed to wastewater contamination

Complexities and complications of extreme obesity

Obesity is a common chronic disorder and has detrimental long-term consequences if left untreated. Herein, we report a case of a young lady who suffered from morbid obesity and many of its consequences, and we present a literature review of these complications. While the cause of obesity is multifactorial, the genetic component is particularly important in the pathophysiology of marked obesity. Resistance to Leptin is considered one of the main causes of obesity. There is a unique relationship between polycystic ovary syndrome and obesity, as observed in our case. Obesity is associated with cardiovascular and lung diseases such as heart failure, thromboembolic disease, sleep apnea, and pulmonary hypertension. Our patient had cardiomegaly (730 gm) with eccentric hypertrophy of left and right ventricles. The coronary arteries and aorta were free of atherosclerosis, which is a surprising finding that relates to the mysterious phenomenon of obesity paradox. The terminal event in our young woman was multiple segmental and subsegmental pulmonary arterial thrombi/ thromboemboli superimposed on chronic cardiopulmonary stress due to massive obesity

Violin Master Class with Marilyn McDonald

Marilyn McDonald, a founding member of the Smithson Quartet and the Castle Trio, currently plays in the Axelrod Quartet in residence at the Smithsonian Institution and so named in honor of the donor of the decorated Stradivarius instruments on which the quartet performs.https://digitalcommons.usu.edu/music_programs/1097/thumbnail.jp

Bringing Antarctica to the lab: a polar desert environmental chamber to study the response of Antarctic microbial communities to climate change

Polar deserts contain unique and sensitive communities responsive to climate-associated habitat changes. However, unlike temperate desert ecosystems, characterizing and predicting the responses of polar ecosystems to environmental change remains a significant challenge due to logistical constraints. Here we aim to demonstrate the use of a custom-designed Polar Desert Environmental Chamber (PDEC) to perform off-continent experimental ecological research. We did so by characterizing the structure and composition of arid edaphic bacterial communities collected from the McMurdo Dry Valleys during a simulated wetting event. The results were discussed in light of previous field observations. Rapid structural and compositional changes were observed during wetting and re-drying treatments. Those were driven by changes in the relative abundance of coexisting taxa, which fluctuated asynchronously over time in response to the treatments. While selection was the main ecological factor influencing communities during dry conditions or the initial wetting, with prolonged exposure to wetness, neutral processes began to drive community assembly. Ultimately, these observations reflect different adaptative responses from microbial taxa to water stress, which can be argued as beneficial to increasing resilience in polar deserts. Our findings demonstrate that experiments conducted in PDEC provide valuable contextual data on community response to environmental change and can accelerate our ability to assess biological thresholds to change within polar desert ecosystems. We advocate that, with careful consideration of key emulated environmental attributes, laboratory-based Antarctic research can complement fieldwork to achieve a nuanced and evidence-based understanding of the ecology of Antarctica’s ice-free regions

Towards a rational design of solid drug nanoparticles with optimised pharmacological properties.

Solid drug nanoparticles (SDNs) are a nanotechnology with favourable characteristics to enhance drug delivery and improve the treatment of several diseases, showing benefit for improved oral bioavailability and injectable long-acting medicines. The physicochemical properties and composition of nanoformulations can influence the absorption, distribution, and elimination of nanoparticles; consequently, the development of nanoparticles for drug delivery should consider the potential role of nanoparticle characteristics in the definition of pharmacokinetics. The aim of this study was to investigate the pharmacological behaviour of efavirenz SDNs and the identification of optimal nanoparticle properties and composition. Seventy-seven efavirenz SDNs were included in the analysis. Cellular accumulation was evaluated in HepG2 (hepatic) and Caco-2 (intestinal), CEM (lymphocyte), THP1 (monocyte), and A-THP1 (macrophage) cell lines. Apparent intestinal permeability (Papp) was measured using a monolayer of Caco-2 cells. The Papp values were used to evaluate the potential benefit on pharmacokinetics using a physiologically based pharmacokinetic model. The generated SDNs had an enhanced intestinal permeability and accumulation in different cell lines compared to the traditional formulation of efavirenz. Nanoparticle size and excipient choice influenced efavirenz apparent permeability and cellular accumulation, and this appeared to be cell line dependent. These findings represent a valuable platform for the design of SDNs, giving an empirical background for the selection of optimal nanoparticle characteristics and composition. Understanding how nanoparticle components and physicochemical properties influence pharmacological patterns will enable the rational design of SDNs with desirable pharmacokinetics

Geochemically defined space-for-time transects successfully capture microbial dynamics along lacustrine chronosequences in a polar desert

The space-for-time substitution approach provides a valuable empirical assessment to infer temporal effects of disturbance from spatial gradients. Applied to predict the response of different ecosystems under current climate change scenarios, it remains poorly tested in microbial ecology studies, partly due to the trophic complexity of the ecosystems typically studied. The McMurdo Dry Valleys (MDV) of Antarctica represent a trophically simple polar desert projected to experience drastic changes in water availability under current climate change scenarios. We used this ideal model system to develop and validate a microbial space-for-time sampling approach, using the variation of geochemical profiles that follow alterations in water availability and reflect past changes in the system. Our framework measured soil electrical conductivity, pH, and water activity in situ to geochemically define 17 space-for-time transects from the shores of four dynamic and two static Dry Valley lakes. We identified microbial taxa that are consistently responsive to changes in wetness in the soils and reliably associated with long-term dry or wet edaphic conditions. Comparisons between transects defined at static (open-basin) and dynamic (closed-basin) lakes highlighted the capacity for geochemically defined space-for-time gradients to identify lasting deterministic impacts of historical changes in water presence on the structure and diversity of extant microbial communities. We highlight the potential for geochemically defined space-for-time transects to resolve legacy impacts of environmental change when used in conjunction with static and dynamic scenarios, and to inform future environmental scenarios through changes in the microbial community structure, composition, and diversity