Sodium retention in rats with liver cirrhosis is associated with increased renal abundance of NaCl cotransporter (NCC)

Background. Liver cirrhosis is associated with enhanced renal tubular sodium retention, the mechanism of which is still debated. We hypothesized that liver cirrhosis is associated with increased expression of renal epithelial sodium transporter(s). Methods. Liver cirrhosis was induced by bile duct ligation (BDL) in rats. Steady state mRNA of ENaC subunits α, β, γ serum and glucocorticoid inducible kinase (Sgk1) were measured by TaqMan PCR in kidney homogenates at week 1, 2, 3 and 4 after BDL. Renal protein content of ENaC subunits, ubiquitin-protein-ligase Nedd4-2 and NaCl cotransporter (NCC) were assessed by western blot. Subcellular localization of ENaC subunits and NCC were analysed by immunohistochemistry. Results. Steady state mRNA of ENaC α, β and γ were unchanged during the 4 weeks investigated, while ENaC protein decreased most prominently at week 2 (control vs BDL; α, −46%; β, −81%; and γ, −63%; n = 6). Subcellular localization of ENaC subunits was not altered at week 2. Sgk1 mRNA did not change, whereas Nedd4-2 protein was reduced by >50% 2-4 weeks after BDL. NCC protein significantly increased at week 1 (control vs BDL: +66%, n = 6, P<0.05) and decreased at week 3 (control vs BDL: −85%, n = 6, P<0.0005). Conclusions. Enhanced abundance of NCC was observed in the initial stage after BDL, followed by a marked decrease. ENaC transcription, translation or cell surface abundance was not increased after BD

Electric fields control water-gated proton transfer in cytochrome c oxidase

Funding Information: ACKNOWLEDGMENTS. This work was funded by the Knut and Alice Wallenberg Foundation (2019.0251 and 2019.0043 to V.R.I.K.). V.R.I.K. also acknowledges support from the German Research Foundation (DFG) via the Collaborative Research Centre (SFB1078) as Mercator Fellow. Computational resources were provided by Funding Information: the Swedish National Infrastructure for Computing (SNIC 2021/1-40, SNIC 2022/1-29) at the Center of High-Performance Computing (PDC), and by the Leibniz-Rechenzentrum. M.W. was supported by the Institute of Biotechnology, University of Helsinki. Funding Information: This work was funded by the Knut and Alice Wallenberg Foundation (2019.0251 and 2019.0043 to V.R.I.K.). V.R.I.K. also acknowledges support from the German Research Foundation (DFG) via the Collaborative Research Centre (SFB1078) as Mercator Fellow. Computational resources were provided by the Swedish National Infrastructure for Computing (SNIC 2021/1-40, SNIC 2022/1-29) at the Center of High-Performance Computing (PDC), and by the Leibniz-Rechenzentrum. M.W. was supported by the Institute of Biotechnology, University of Helsinki. Publisher Copyright: Copyright © 2022 the Author(s). Published by PNAS.Aerobic life is powered by membrane-bound enzymes that catalyze the transfer of electrons to oxygen and protons across a biological membrane. Cytochrome c oxidase (CcO) functions as a terminal electron acceptor in mitochondrial and bacterial respiratory chains, driving cellular respiration and transducing the free energy from O2 reduction into proton pumping. Here we show that CcO creates orientated electric fields around a nonpolar cavity next to the active site, establishing a molecular switch that directs the protons along distinct pathways. By combining large-scale quantum chemical density functional theory (DFT) calculations with hybrid quantum mechanics/ molecular mechanics (QM/MM) simulations and atomistic molecular dynamics (MD) explorations, we find that reduction of the electron donor, heme a, leads to dissociation of an arginine (Arg438)-heme a3 D-propionate ion-pair. This ion-pair dissociation creates a strong electric field of up to 1 V A21 along a water-mediated proton array leading to a transient proton loading site (PLS) near the active site. Protonation of the PLS triggers the reduction of the active site, which in turn aligns the electric field vectors along a second, "chemical," proton pathway. We find a linear energy relationship of the proton transfer barrier with the electric field strength that explains the effectivity of the gating process. Our mechanism shows distinct similarities to principles also found in other energy-converting enzymes, suggesting that orientated electric fields generally control enzyme catalysis.Peer reviewe

Glucose-Dependent Insulinotropic Polypeptide (GIP) Induces Calcitonin Gene-Related Peptide (CGRP)-I and Procalcitonin (Pro-CT) Production in Human Adipocytes

Context: Increased plasma levels of glucose-dependent insulinotropic polypeptide (GIP), calcitonin CT gene-related peptide (CGRP)-I, and procalcitonin (Pro-CT) are associated with obesity. Adipocytes express functional GIP receptors and the CT peptides Pro-CT and CGRP-I. However, a link between GIP and CT peptides has not been studied yet. Objective: The objective of the study was the assessment of the GIP effect on the expression and secretion of CGRP-I and Pro-CT in human adipocytes, CGRP-I and CT gene expression in adipose tissue (AT) from obese vs. lean subjects, and plasma levels of CGRP-I and Pro-CT after a high-fat meal in obese patients. Design and Participants: Human preadipocyte-derived adipocytes, differentiated in vitro, were treated with GIP. mRNA expression and protein secretion of CGRP-I and Pro-CT were measured. Human CGRP-I and CT mRNA expression in AT and CGRP-I and Pro-CT plasma concentrations were assessed. Results: Treatment with 1 nm GIP induced CGRP-I mRNA expression 6.9 ± 1.0-fold (P > 0.001 vs. control) after 2 h and CT gene expression 14.0 ± 1.7-fold (P > 0.001 vs. control) after 6 h. GIP stimulated CGRP-I secretion 1.7 ± 0.2-fold (P > 0.05 vs. control) after 1 h. In AT samples of obese subjects, CGRP-I mRNA expression was higher in sc AT (P > 0.05 vs. lean subjects), whereas CT expression was higher in visceral AT (P > 0.05 vs. lean subjects). CGRP-I plasma levels increased after a high-fat meal in obese patients. Conclusion: GIP induces CGRP-I and CT expression in human adipocytes. Therefore, elevated Pro-CT and CGRP-I levels in obesity might result from GIP-induced Pro-CT and CGRP-I release in AT and might be triggered by a high-fat diet. How these findings relate to the metabolic complications of obesity warrants further investigations

The Development of Healthcare Jobs in the COVID-Pandemic-A New Economic Market

BACKGROUND The COVID-19 pandemic commenced in China and has caused the death of numerous people globally. Despite the adverse effects, the outbreak has created room for job opportunities in healthcare, particularly the pharmaceutical domain. The main goal of this study is to examine how the current pandemic has triggered job creation in the healthcare domain and created a new economic market. METHODS The study used the Preferred Reporting Items for Systematic and Meta-analyses for Scoping Review (PRISMA-ScR) to structure the manuscript and the subheadings to use. The source used to gather data is the PubMed database. RESULTS The study exclusively included fourteen articles, five of which focused on the pharmaceutical sector, three focused on vaccine sales, three on vaccination centers, and three on testing centers. CONCLUSION The COVID-19 pandemic has created job opportunities in the healthcare sector. Most jobs are in the pharmaceutical sector, vaccination, and testing centers. However, more comprehensive research on the topic is necessary to gather conclusive outcomes on whether these jobs will be relevant after the pandemic

Restricted streptomycin use in apple orchards did not adversely alter the soil bacteria communities

Streptomycin has been authorized for restricted use in the prevention of the fire blight disease of pome fruit orchards in the EU and Switzerland. This study addresses the important topic of the influence of the use of streptomycin in agriculture on the total bacteria community within the soil ecosystem. Soil samples were taken from soils under apple trees, prior to streptomycin application and 2 weeks post streptomycin application or water application (untreated control). High throughput 16S rRNA gene amplicon sequencing was used to generate datasets from the soils under apple trees in apple orchards from three different locations in Switzerland. We hypothesized that the use of streptomycin would reduce the bacterial diversity within the soil samples and enhance a reduction in the variety of taxa present. Bacterial species such as Pseudomonas, Burkholderia, and Stenotrophomonas are intrinsically resistant to many antibiotics and as such it is of interest to investigate if the use of streptomycin provided a selective advantage for these bacteria in the soil ecosystem. The application of streptomycin did not influence the abundance and diversities of major bacteria taxa of the soils or the Pseudomonas, Burkholderia, and Stenotrophomonas species. We also discovered that apple orchards under the same management practices, did not harbor the same bacterial communities. The restricted application of streptomycin in the protection of apple orchards from the fire blight pathogen Erwinia amylovora under the guidelines in Switzerland did not alter either the bacterial diversity or abundance within these soil ecosystems

Stakeholder-Driven Design Evolution of the Leveraged Freedom Chair Developing World Wheelchair

The Leveraged Freedom Chair (LFC) is a low-cost, all-terrain, variable mechanical advantage, lever-propelled wheelchair designed for use in developing countries. The user effectively changes gear by shifting his hands along the levers; grasping near the ends increases torque delivered to the drive-train, while grasping near the pivots enables a larger angular displacement with every stroke, which increases angular velocity in the drivetrain and makes the chair go faster. This paper chronicles the design evolution of the LFC through three user trials in East Africa, Guatemala, and India. Feedback from test subjects was used to refine the chair between trials, resulting in a device 9.1 kg (20 lbs) lighter, 8.9 cm (3.5 in) narrower, and with a center of gravity 12.7 cm (5 in) lower than the first iteration. Survey data substantiated increases in performance after successive iterations. Quantitative biomechanical performance data were also measured during the Guatemala and India trials, which showed the LFC to be 76 percent faster and 41 percent more efficient during a common daily commute and able to produce 51 percent higher peak propulsion force compared to conventional, pushrim-propelled wheelchairs

BAYESIAN ANALYSIS OF ADAPTIVE ONE-FACTOR-AT-A-TIME EXPERIMENTATION

ABSTRACT This paper considers the problem of achieving improvement

An Experimental Methodology to Evaluate Concept Generation Procedures Based on Quantitative Lifecycle Performance

This study presents an experimental methodology to measure how concept generation procedures can affect the anticipated lifecycle performance of engineering systems design concepts. The methodology is based on objective and quantitative measurements of anticipated lifecycle performance of the design concepts. It merges cognitive and computer-aided techniques from the fields of collaboration engineering, creativity, and engineering design. It complements the body of existing techniques relying on subjective expert assessments, and other objective metrics not explicitly measuring anticipated lifecycle performance (e.g. development time and cost). Application of the methodology is demonstrated through evaluation of design procedures generating flexibility in engineering systems design. Experiments had ninety participants generate creative design alternatives to a simplified real estate development design problem. Thirty-two teams of two to three participants performed the collaborative design exercise. An online Group-Support System interface enabled efficient data collection and analysis. A computationally efficient mid-fidelity model was used to evaluate flexible design concepts quantitatively based on real options analysis techniques.Massachusetts Institute of Technology. Center for Real EstateNatural Sciences and Engineering Research Council of CanadaMassachusetts Institute of Technology. Engineering Systems DivisionSingapore University of Technology and Design. International Design Cente

Empirical evaluation of procedures to generate flexibility in engineering systems and improve lifecycle performance

The design of engineering systems like airports, communication infrastructures, and real estate projects today is growing in complexity. Designers need to consider socio-technical uncertainties, intricacies, and processes in the long-term strategic deployment and operations of these systems. Flexibility in engineering design provides ways to deal with this complexity. It enables engineering systems to change in the face of uncertainty to reduce impacts from downside scenarios (e.g., unfavorable market conditions) while capitalizing on upside opportunities (e.g., new technology). Many case studies have shown that flexibility can improve anticipated lifecycle performance (e.g., expected economic value) compared to current design and evaluation approaches. It is a difficult process requiring guidance and must be done at an early conceptual stage. The literature offers little guidance on procedures helping designers do this systematically in a collaborative context. This study investigated the effects of two educational training procedures on flexibility (current vs. explicit) and two ideation procedures (free undirected brainstorming vs. prompting) to guide this process and improve anticipated lifecycle performance. Controlled experiments were conducted with ninety participants working on a simplified engineering systems design problem. Results suggest that a prompting mechanism for flexibility can help generate more flexible design concepts than free undirected brainstorming. These concepts can improve performance significantly (by up to 36 %) compared to a benchmark design—even though users did not expect improved quality of results. Explicit training on flexibility can improve user satisfaction with the process, results, and results quality in comparison with current engineering and design training on flexibility. These findings give insights into the crafting and application of simple, intuitive, and efficient procedures to improve lifecycle performance by means of flexibility and performance that may be left aside with existing design approaches. The experimental results are promising toward further evaluation in a real-world setting.National University of Singapore (Faculty Research Committee via MOE AcRF Tier 1 grant WBS R-266-000-061-133)Massachusetts Institute of Technology. Engineering Systems DivisionMassachusetts Institute of Technology. Systems Design and Management ProgramMassachusetts Institute of Technology. Center for Real EstateMitre CorporationNatural Sciences and Engineering Research Council of CanadaFonds québécois de la recherche sur la société et la cultureMIT-Portugal ProgramSUTD-MIT International Design Centre (IDC)Cambridge-MIT InstituteFondation Desjardin

Whole blood assessment of antigen specific cellular immune response by real time quantitative PCR: a versatile monitoring and discovery tool

BACKGROUND: Monitoring of cellular immune responses is indispensable in a number of clinical research areas, including microbiology, virology, oncology and autoimmunity. Purification and culture of peripheral blood mononuclear cells and rapid access to specialized equipment are usually required. We developed a whole blood (WB) technique monitoring antigen specific cellular immune response in vaccinated or naturally sensitized individuals. METHODS: WB (300 microl) was incubated at 37 degrees C with specific antigens, in the form of peptides or commercial vaccines for 5-16 hours. Following RNAlater addition to stabilize RNA, the mixture could be stored over one week at room temperature or at 4 degrees C. Total RNA was then extracted, reverse transcribed and amplified in quantitative real-time PCR (qRT-PCR) assays with primers and probes specific for cytokine and/or chemokine genes. RESULTS: Spiking experiments demonstrated that this technique could detect antigen specific cytokine gene expression from 50 cytotoxic T lymphocytes (CTL) diluted in 300 microl WB. Furthermore, the high sensitivity of this method could be confirmed ex-vivo by the successful detection of CD8+ T cell responses against HCMV, EBV and influenza virus derived HLA-A0201 restricted epitopes, which was significantly correlated with specific multimer staining. Importantly, a highly significant (p = 0.000009) correlation between hepatitis B surface antigen (HBsAg) stimulated IL-2 gene expression, as detectable in WB, and specific antibody titers was observed in donors vaccinated against hepatitis B virus (HBV) between six months and twenty years before the tests. To identify additional markers of potential clinical relevance, expression of chemokine genes was also evaluated. Indeed, HBsAg stimulated expression of MIP-1beta (CCL4) gene was highly significantly (p = 0.0006) correlated with specific antibody titers. Moreover, a longitudinal study on response to influenza vaccine demonstrated a significant increase of antigen specific IFN-gamma gene expression two weeks after immunization, declining thereafter, whereas increased IL-2 gene expression was still detectable four months after vaccination. CONCLUSION: This method, easily amenable to automation, might qualify as technology of choice for high throughput screening of immune responses to large panels of antigens from cohorts of donors. Although analysis of cytokine gene expression requires adequate laboratory infrastructure, initial antigen stimulation and storage of test probes can be performed with minimal equipment and time requirements. This might prove important in "field" studies with difficult access to laboratory facilities