A comparative study of NS1 and IgM using enzyme-linked immunosorbent assay and immunochromatography test for detection of dengue.

Background: Dengue is the most common arboviral infection that spreads by Aedes aegypti and Aedes albopictus mosquitoes, and is quickly gaining prominence as a major mosquito-borne viral disease. One of the major public health issues is dengue fever (DF), which can also cause dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS). Therefore, this study focused on comparison of dengue antigen non-structural protein (NS1) and immunoglobulin M (IgM) using enzyme-linked immunosorbent assay (ELISA) and immunochromatography test (ICT) for detection of dengue. Method: In a Tertiary Care Hospital (TCH), sociodemographic status of probable dengue cases from February 2021 to February 2022 was studied. The results of the Dengue Antigen NS1 and IgM ICT, Dengue NS1 Microlisa, and Dengue IgM Microlisa were compared in order to determine the effective one at managing patients and preventing complications like DHF and DSS. Results: In distribution of 100 ICT reactive samples, 50% were NS1 reactive and 50% were IgM reactive. One hundred ICT reactive samples were further processed for IgM antibody capture enzyme-linked immunosorbent assay (MAC-ELISA) for both NS1 and IgM. Sensitivity and specificity of NS1 ICT were 89.3% and 71.4% and that of IgM ICT was 88% and 64.5%. As a result of antigenic cross-reactivity, false positive cases were reported. Platelet count of the patients was correlated with an optical density (OD) value of ELISA for both NS1 and IgM. In the present study, patients having low platelet count showed high OD value. Conclusion: In cases of severe thrombocytopenia (platelet count <50000), early diagnosis by screening ICT and confirmation by ELISA (NS1 and IgM) would reduce the complications like DHF and DSS.

Exploring the labour market outcomes of the risk factors for non-communicable diseases: A systematic review.

Objective: To look at the associations between labour market outcomes and major risk factors for non-communicable diseases (NCDs) (smoking, heavy alcohol consumption), key metabolic changes resultant of the risk factors (overweight and obesity, hypertension, type 2 diabetes), and major depressive disorder, and examine any gender differences. Design: Systematic review of cohort and longitudinal studies, to establish causality between exposures and outcomes. Methods: A systematic literature search was conducted in MEDLINE (Ovid), Embase (Ovid), EconLit (EBSCO), EconPapers, and Cochrane Database of Systematic Reviews, from inception to July 2022 for all peer-reviewed literature published, guided by the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) framework. Results: 109 studies were eligible for this review. All studies were published in English. 96% of the studies were conducted in high-income countries with 63% from Europe and Central Asia. High BMI was the most frequently reported exposure (reported by 46% of the studies), while income was the most studied outcome (reported by 33% of studies). Though not all estimates presented in the literature can be interpreted as causal impacts, 77% of the studies reported significant (p < 0.05) adverse associations between the exposures and outcomes. Conclusions: All of the studies included in this review that looked at plausible causal relationships between NCD risk factors and labour market outcomes were from high-income and upper-middle-income countries (USA, northern European countries, and South Korea). Based on these studies, we found that individuals with overweight or obesity, diabetes, hypertension, depressive disorders, excessive alcohol use, and cigarette use are more likely to have lower rates of employment, lower income, and higher rates of sickness absence and disability pension.

Exploring the application of behaviour change technique taxonomies in childhood obesity prevention interventions: A systematic scoping review.

Behaviour change technique (BCT) taxonomies provide one approach to unpack the complexity of childhood obesity prevention interventions. This scoping review sought to examine how BCT taxonomies have been applied to understand childhood obesity prevention interventions targeting children aged 12 years or under and/or their caregivers. A systematic search was conducted in Medline, Embase, PsycINFO, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, CINAHL and PROSPERO, to capture all eligible research up to February 2021. No limits were placed on country, language, publication dates, or full text availability. Eligible studies included any study design that applied a BCT taxonomy and evaluated behavioural childhood obesity prevention interventions targeting children aged 12 years or under and/or their parents or caregivers. Sixty-three records, describing 54 discrete studies were included; 32 applied a BCT taxonomy prospectively (i.e., to design interventions) and 23 retrospectively (i.e., to assess interventions), 1 study did both. There was substantial variation in the methods used to apply BCT taxonomies and to report BCT-related methods and results. There was a paucity of detail reported in how BCTs were selected in studies applying BCT taxonomies prospectively. Our review provides important insight into the application of BCT taxonomies in childhood obesity prevention and several ongoing challenges, pointing to the need for best practice reporting guidance.

Enhanced autophagic-lysosomal activity and increased BAG3-mediated selective macroautophagy as adaptive response of neuronal cells to chronic oxidative stress.

Oxidative stress and a disturbed cellular protein homeostasis (proteostasis) belong to the most important hallmarks of aging and of neurodegenerative disorders. The proteasomal and autophagic-lysosomal degradation pathways are key measures to maintain proteostasis. Here, we report that hippocampal cells selected for full adaptation and resistance to oxidative stress induced by hydrogen peroxide (oxidative stress-resistant cells, OxSR cells) showed a massive increase in the expression of components of the cellular autophagic-lysosomal network and a significantly higher overall autophagic activity. A comparative expression analysis revealed that distinct key regulators of autophagy are upregulated in OxSR cells. The observed adaptive autophagic response was found to be independent of the upstream autophagy regulator mTOR but is accompanied by a significant upregulation of further downstream components of the canonical autophagy network such as Beclin1, WIPI1 and the transmembrane ATG9 proteins. Interestingly, the expression of the HSP70 co-chaperone BAG3, mediator of BAG3-mediated selective macroautophagy and highly relevant for the clearance of aggregated proteins in cells, was found to be increased in OxSR cells that were consequently able to effectively overcome proteotoxic stress. Overexpression of BAG3 in oxidative stress-sensitive HT22 wildtype cells partly established the vesicular phenotype and the enhanced autophagic flux seen in OxSR cells suggesting that BAG3 takes over an important part in the adaptation process. A full proteome analysis demonstrated additional changes in the expression of mitochondrial proteins, metabolic enzymes and different pathway regulators in OxSR cells as consequence of the adaptation to oxidative stress in addition to autophagy-related proteins. Taken together, this analysis revealed a wide variety of pathways and players that act as adaptive response to chronic redox stress in neuronal cells.

AC Electric Field-Induced Trapping of Microparticles in Pinched Microconfinements.

The trapping of charged microparticles under confinement in a converging-diverging microchannel, under a symmetric AC field of tunable frequency, is studied. We show that at low frequencies, the trapping characteristics stem from the competing effects of positive dielectrophoresis and the linear electrokinetic phenomena of electroosmosis and electrophoresis. It is found, somewhat unexpectedly, that electroosmosis and electrophoresis significantly affect the concentration profile of the trapped analyte, even for a symmetric AC field. However, at intermediate frequencies, the microparticle trapping mechanism is predominantly a consequence of positive dielectrophoresis. We substantiate our experimental results for the microparticle concentration distribution, along the converging-diverging microchannel, with a detailed theoretical analysis that takes into account all of the relevant frequency-dependent electrokinetic phenomena. This study should be useful in understanding the response of biological components such as cells to applied AC fields. Moreover, it will have potential applications in the design of efficient point-of-care diagnostic devices for detecting biomarkers and also possibly in some recent strategies in cancer therapy using AC fields.

Combined effects of surface roughness and wetting characteristics on the moving contact line in microchannel flows.

The present study investigates moving contact lines in microfluidic confinements with rough topographies modeled with random generating functions. Using matched asymptotic expansion, the description of the whole contact line is obtained and the dynamic contact angle is extracted by extrapolating the bulk meniscus to the channel wall. Significant variations are observed in the contact angle because of the heterogeneities of the confining walls of the microfluidic channel. The effects of the surface wetting condition also play a crucial role in altering the description of the contact line bearing particular nontrivial interactions with the topological features of the solid boundaries. In an effort to assess the underlying consequences, two different surface wetting conditions are studied; namely, complete wetting substrate and partial wetting substrate. Our studies reveal that the consequent wetting characteristics are strongly influenced by action of intermolecular forces in presence of surface roughness. The effect of slip, correlation length, and roughness parameters on the dynamic contact angle have been also investigated.

Surface-charge-induced alteration of nanovortex patterning in nanoscale confinements with patterned wettability gradients.

We characterize the generation of flow vortices in nanoscale confinements under the combined effects of patterned surface charge density and substrate wettability. Using molecular dynamics simulations, we elucidate the effects of ion solvation and steric interactions toward influencing the resultant transport characteristics, which are otherwise difficult to resolve using classical electrokinetic theory. We also evaluate the velocity slip (local and global) as well as vorticity parameters, in an effort to assess the implications of the generated flow structure from a pseudocontinuum viewpoint. Results from the present study are expected to provide valuable insights on augmentation of nanoscale mixing.

Effect of dispersion on the diffusion zone in two-phase laminar flows in microchannels.

Aim of the present work is to investigate the reaction-diffusion process of a two species system under laminar flow in a T-shaped microchannel. A zone formed at the interface between the aqueous solutions of these two species is affected by advection and diffusion. Through theoretical analyses and experimental results, the effect of dispersion has been shown to influence this diffusion zone. We have defined a parameter called effective diffusivity, to account for the dispersion effects and observed it to be a function of the channel Peclet number. In the limiting case of low Peclet number, this parameter is constant and turns out to be equal to the molecular diffusivity. We have also related effective diffusivity and the dispersion coefficient through scaling estimates.

Enhancement of static incubation time in microfluidic cell culture platforms exploiting extended air-liquid interface.

Microfluidics based cell culture applications have facilitated the study of cellular dynamics at the single entity level. Yet, long term versions of such applications in a static framework suffer from the fast exhaustion of available oxygen, dissolved in the limited media volume available per cell, within the microconfined environment. In order to circumvent such drawbacks, we have improvised a microfluidic cell culture platform for prolonged sustenance of adherent mammalian cells by formation of an air-liquid interface through functionalizing inner surfaces of a polydimethylsiloxane (PDMS) based microdevice. We have demonstrated an augmented static incubation time for different cell lines using this approach.

Effect of submicron particles on electrowetting on dielectrics (EWOD) of sessile droplets.

The present study elucidates the effects of included submicron-sized particles on the wetting behavior of sessile droplets under the influence of applied electric field in an electro-wetting-on-dielectric (EWOD) configuration. A thermodynamic description using an energy minimization approach is used to analyze the experimental results related to the effects of the included particles on the EWOD phenomenon, considering the effects of line tension as well. The effects of particle size and concentration on interfacial areas are included in the model to analyze the wetting characteristics. Experiments are also conducted with submicron-sizes latex beads, in an effort to elucidate the related phenomena. It is further postulated that these beads act as suspended dielectrics in the droplet, thereby mimicking a system of two capacitors in series. An effective electrical permittivity of the composite medium is used to study the experimental results related to contact angle changes at different concentrations and diameters of submicron particles in the droplet.

Anomalous mixing behaviour in rotationally actuated microfluidic devices.

We analyse the characteristics of two-fluid mixing in T-shaped microchannels on rotating platforms (Lab-on-a-Compact-Disk framework). Three regimes of mixing were identified based on the distinct flow behaviour in each of these regimes. A diffusion-based mixing regime was obtained for low rotation speeds. A Coriolis force based mixing regime was observed for intermediate rotation speeds, which introduced some nontrivial aspects in the mixing behaviour, which was explained through scaling analysis. At very high rotational speeds, rapid mixing close to the junction was achieved by exploiting flow instabilities (instability based mixing). A good agreement between the theoretical calculations and the experimental observations was obtained.

Interfacial phenomena and dynamic contact angle modulation in microcapillary flows subjected to electroosmotic actuation.

The dynamic evolution of an incompressible liquid meniscus inside a microcapillary is investigated, under the combined influences of viscous, capillary, intermolecular, pondermotive, and electroosmotic effects. In the limit of small capillary numbers, an advancing meniscus shape is shown to merge smoothly with the precursor film, using matched asymptotic analysis. A scaling relationship is also established for the dynamic contact angle as a nondimensional function of the capillary number and the applied electrical voltage. The analysis is further generalized by invoking a kinetic slip model for overcoming the constraints of meniscus tip singularity. The kinetic slip model is subsequently utilized to analyze the interfacial dynamics from the perspective of the results obtained from the matched asymptotic analysis. A generalization is achieved in this regard, which may provide a sound basis for controlling the topographical features of a dynamically evolving meniscus in a microcapillary subjected to electrokinetic effects. These results are also in excellent agreement with the experimental findings over a wide range of capillary number values.