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Abstract Background Hibernation (torpor) is a strategy to survive extreme environmental conditions, associated with a significant decrease in metabolism and body temperature. The inducibility by the environment of torpor for facultative hibernators designates epigenetic mechanisms as likely candidates for regulation. Therefore, we set out to unravel epigenetics in the liver of a facultative hibernator, Syrian hamster (Mesocricetus auratus), sampled at different phases during hibernation, by assessing the expression of epigenetic writer and eraser enzymes, histone acetylation dynamics, and DNA methylation levels. Results Expression of epigenetic writers/erasers confirmed previously reported results obtained in obligatory hibernators, but might point to a mechanism specific for facultative hibernators, e.g., differential expression of histone acetyltransferases (HATs; KAT6A, KAT6B, KAT7, and KAT13D/CLOCK). These findings were in accordance with observed changes in histone H3 and H4 acetylation changes. Overall histone deacetylase (HDAC) activity was highest in torpor. No differences were detected in DNA methylation throughout all phases. Conclusion Our study thus points to histone acetylation as an important player in facultative hamster hibernation, which may underlie the orchestration of gene expression changes throughout hibernation.

IntroductionHIV treating physicians in the Netherlands follow the guidelines of the Department of Health and Human Services (DHHS). Most of these recommended initial regimens are single-tablet regimens (STRs), which incur higher costs. By the end of 2017, generic NRTI backbones had become widely available, offering a potentially cheaper multi-tablet regimen. This study aimed to evaluate guideline compliance in people with HIV who started antiretroviral therapy (ART), the uptake of generic multi-tablet regimens (gMTRs), and associated medication costs.MethodsThis retrospective cohort study used data from the Dutch HIV Monitoring Foundation to determine the proportion of treatment-naïve people entering care who initiated ART according to the DHHS and type of ART regimens prescribed between January 2016 and December 2020. We analyzed ART prescriptions, both at the national level and per individual HIV treatment centers. We calculated the monthly ART costs based on Dutch medicine prices listed on www.medicijnkosten.nl for each calendar year.ResultsIn 2016, an integrase inhibitor-containing regimen was initiated in 77.3% which increased to 87.8% in 2020. The compliance rate to DHHS-recommended initial regimens ranged from 82.8% in 2016 to 90.9% in 2020. Most patients received single-tablet regimens, 81.3% in 2016 to 60.3% in 2020. After the introduction the gMTRs showed a steady increase from 17.8% in 2018 to 37.8% in 2020. The cost of the first-line regimen per patient decreased by 22.9% in 2020 compared with 2017. The decrease was larger in centers where treatment-naïve individuals with HIV were preferentially initiated on a gMTR.ConclusionsThere was a high compliance to the "DHHS-recommended initial regimens for most people with HIV" in the Netherlands. Most people who initiated ART received STRs, although the percentage of people who started on STRs gradually decreased over time. The use of gMTRs increased over time and was associated with lower medication costs.

There has been a recent upsurge in human cases of leptospirosis in New Zealand, with wildlife a suspected emerging source, but up-to-date knowledge on this topic is lacking. We conducted a cross-sectional study in two farm environments to estimate Leptospira seroprevalence in wildlife and sympatric livestock, PCR/culture prevalence in wildlife, and compare seroprevalence and prevalence between species, sex, and age groups. Traps targeting house mice (Mus musculus), black rats (Rattus rattus), hedgehogs (Erinaceus europaeus) and brushtail possums (Trichosurus vulpecula) were set for 10 trap-nights in March-April 2017 on a dairy (A) and a beef and sheep (B) farm. Trapped wild animals and an age-stratified random sample of domestic animals, namely cattle, sheep and working dogs were blood sampled. Sera were tested by microagglutination test for five serogroups and titres compared using a Proportional Similarity Index (PSI). Wildlife kidneys were sampled for culture and qPCR targeting the lipL32 gene. True prevalence in mice was assessed using occupancy modelling by collating different laboratory results. Infection profiles varied by species, age group and farm. At the MAT cut-point of ≥ 48, up to 78% of wildlife species, and 16-99% of domestic animals were seropositive. Five of nine hedgehogs, 23/105 mice and 1/14 black rats reacted to L. borgpetersenii sv Ballum. The sera of 4/18 possums and 4/9 hedgehogs reacted to L. borgpetersenii sv Hardjobovis whilst 1/18 possums and 1/9 hedgehogs reacted to Tarassovi. In ruminants, seroprevalence for Hardjobovis and Pomona ranged 0-90% and 0-71% depending on the species and age group. Titres against Ballum, Tarassovi and Copenhageni were also observed in 4-20%, 0-25% and 0-21% of domestic species, respectively. The PSI indicated rodents and livestock had the most dissimilar serological responses. Three of nine hedgehogs, 31/105 mice and 2/14 rats were carrying leptospires (PCR and/or culture positive). True prevalence estimated by occupancy modelling in mice was 38% [95% Credible Interval 26, 51%] on Farm A and 22% [11, 40%] on Farm B. In the same environment, exposure to serovars found in wildlife species was commonly detected in livestock. Transmission pathways between and within species should be assessed to help in the development of efficient mitigation strategies against Leptospira.

The increasing prevalence of people with Parkinson's disease (PD) necessitates a high priority for finding interventions to delay or even prevent the onset of PD. There is converging evidence that exercise may exert disease-modifying effects in people with clinically manifest PD, but whether exercise also has a preventive effect or is able to modify the progression of the pathology in the prodromal phase of PD is unclear. Here we provide some considerations on the design of trials that aim to prevent PD through exercise. First, we discuss the who could benefit from exercise, and potential exercise-related risks. Second, we discuss what specific components of exercise mediate the putative disease-modifying effects. Third, we address how methodological challenges such as blinding, adherence and remote monitoring could be handled and how we can measure the efficacy of exercise as modifier of the course of prodromal PD. We hope that these considerations help in designing exercise prevention trials for persons at risk of developing PD. [ABSTRACT FROM AUTHOR]

Abstract We perform a global analysis of the low-energy phenomenology of the minimal left-right symmetric model (mLRSM) with parity symmetry. We match the mLRSM to the Standard Model Effective Field Theory Lagrangian at the left-right-symmetry breaking scale and perform a comprehensive fit to low-energy data including mesonic, neutron, and nuclear β-decay processes, ∆F = 1 and ∆F = 2 CP-even and -odd processes in the bottom and strange sectors, and electric dipole moments (EDMs) of nucleons, nuclei, and atoms. We fit the Cabibbo-Kobayashi-Maskawa and mLRSM parameters simultaneously and determine a lower bound on the mass of the right-handed W R boson. In models where a Peccei-Quinn mechanism provides a solution to the strong CP problem, we obtain M W R $$ {M}_{W_R} $$ ≳ 5.5 TeV at 95% C.L. which can be significantly improved with next-generation EDM experiments. In the P-symmetric mLRSM without a Peccei-Quinn mechanism we obtain a more stringent constraint M W R $$ {M}_{W_R} $$ ≳ 17 TeV at 95% C.L., which is difficult to improve with low-energy measurements alone. In all cases, the additional scalar fields of the mLRSM are required to be a few times heavier than the right-handed gauge bosons. We consider a recent discrepancy in tests of first-row unitarity of the CKM matrix. We find that, while TeV-scale W R bosons can alleviate some of the tension found in the V ud,us determinations, a solution to the discrepancy is disfavored when taking into account other low-energy observables within the mLRSM.

Introduction: HIV treating physicians in the Netherlands follow the guidelines of the Department of Health and Human Services (DHHS). Most of these recommended initial regimens are single-tablet regimens (STRs), which incur higher costs. By the end of 2017, generic NRTI backbones had become widely available, offering a potentially cheaper multi-tablet regimen. This study aimed to evaluate guideline compliance in people with HIV who started antiretroviral therapy (ART), the uptake of generic multi-tablet regimens (gMTRs), and associated medication costs. Methods: This retrospective cohort study used data from the Dutch HIV Monitoring Foundation to determine the proportion of treatment-naïve people entering care who initiated ART according to the DHHS and type of ART regimens prescribed between January 2016 and December 2020. We analyzed ART prescriptions, both at the national level and per individual HIV treatment centers. We calculated the monthly ART costs based on Dutch medicine prices listed on www.medicijnkosten.nl for each calendar year. Results: In 2016, an integrase inhibitor-containing regimen was initiated in 77.3% which increased to 87.8% in 2020. The compliance rate to DHHS-recommended initial regimens ranged from 82.8% in 2016 to 90.9% in 2020. Most patients received single-tablet regimens, 81.3% in 2016 to 60.3% in 2020. After the introduction the gMTRs showed a steady increase from 17.8% in 2018 to 37.8% in 2020. The cost of the first-line regimen per patient decreased by 22.9% in 2020 compared with 2017. The decrease was larger in centers where treatment-naïve individuals with HIV were preferentially initiated on a gMTR. Conclusions: There was a high compliance to the "DHHS-recommended initial regimens for most people with HIV" in the Netherlands. Most people who initiated ART received STRs, although the percentage of people who started on STRs gradually decreased over time. The use of gMTRs increased over time and was associated with lower medication costs. [ABSTRACT FROM AUTHOR]

Abstract Background By binding to negatively charged polysaccharides called glycosaminoglycans, sodium can be stored in the body—particularly in the skin—without concurrent water retention. Concordantly, individuals with changed glycosaminoglycan structure (e.g. type 1 diabetes (DM1) and hereditary multiple exostosis (HME) patients) may have altered sodium and water homeostasis. Methods We investigated responses to acute (30-min infusion) and chronic (1-week diet) sodium loading in 8 DM1 patients and 7 HME patients in comparison to 12 healthy controls. Blood samples, urine samples, and skin biopsies were taken to investigate glycosaminoglycan sulfation patterns and both systemic and cellular osmoregulatory responses. Results Hypertonic sodium infusion increased plasma sodium in all groups, but more in DM1 patients than in controls. High sodium diet increased expression of nuclear factor of activated t-cells 5 (NFAT5)—a transcription factor responsive to changes in osmolarity—and moderately sulfated heparan sulfate in skin of healthy controls. In HME patients, skin dermatan sulfate, rather than heparan sulfate, increased in response to high sodium diet, while in DM1 patients, no changes were observed. Conclusion DM1 and HME patients show distinct osmoregulatory responses to sodium loading when comparing to controls with indications for reduced sodium storage capacity in DM1 patients, suggesting that intact glycosaminoglycan biosynthesis is important in sodium and water homeostasis. Trial registration These trials were registered with the Netherlands trial register with registration numbers: NTR4095 ( https://www.trialregister.nl/trial/3933 at 2013-07-29) and NTR4788 ( https://www.trialregister.nl/trial/4645 at 2014-09-12).

Steel shear connections are mainly designed to sustain shear forces. There is limited research assessing the axial response of shear connections, which is important in the evaluation of robustness of steel structures. Structural collapse can be arrested following localized damage if an alternative load path with sufficient capacity is available. In this study, the formation of compressive arching action followed by tensile catenary action is investigated. It is shown that in a column loss scenario, connections may develop significant axial compressive force before catenary action begins; this phenomenon has often been neglected in assessments of connection robustness in the sense that axial force is reported as a tensile action only. The presence of arching action has been confirmed in two experimental programs, and one set is selected for further study using a numerical approach. A simplified analytical model is then presented and compared with the observed axial response of these connections. It is concluded that vertical eccentricity between the centres of rotation of the connections at the two ends of a beam is the principal factor causing the development of a compressive arching force. Another influential parameter that affects the formation of arching action is the stiffness of the surrounding structure. Key words: finite element method, disproportionate collapse, column removal scenario, shear connection, compressive arching action, tensile catenary action. Les entretoises de cisaillement en acier sont principalement concues pour supporter l'effort tranchant. Il existe peu de recherches evaluant la reponse axiale d'entretoises de cisaillement, ce qui est important pour l'evaluation de la robustesse des structures en acier. L'effondrement de la structure peut etre arrete a la suite de dommages localises si une autre voie de contrainte avec une capacite suffisante est disponible. Dans cette etude, la formation d'action de voute de compression suivie d'une action de catenaire en traction est etudiee. Il est montre que dans un contexte de perte de colonne, les entretoises peuvent developper une force de compression axiale significative avant le debut de l'action de catenaire; ce phenomene a souvent ete neglige dans les evaluations de la robustesse des entretoises en ce sens que la force axiale n'est signalee que comme une action en traction. La presence de l'action de voute a ete confirmee dans deux programmes experimentaux et un ensemble est choisi pour une etude plus approfondie en utilisant une approche numerique. Un modele analytique simplifie est ensuite presente et compare a la reponse axiale observee de ces entretoises. On en conclut que l'excentricite verticale entre les centres de rotation des entretoises aux deux extremites d'une poutre est le principal facteur provoquant le developpement d'une force de voute de compression. Un autre parametre qui influe sur la formation de l'action de voute est la rigidite de la structure environnante. [Traduit par la Redaction] Mots-cles : methode des elements finis, effondrement disproportionne, scenario d'enlevement de colonne, entretoise de cisaillement, action de voute de compression, action de la catenaire en traction., 1. Introduction The potential for disproportionate collapse is an important issue in building failure characterization. It is generally accepted that a column removal scenario can be used to assess the [...]

We calculate the lifetime of the deuteron from dimension-six quark operators that violate baryon number by one unit. We construct an effective field theory (EFT) for |ΔB|=1 interactions that give rise to nucleon and ΔB=1 deuteron decay in a systematic expansion. Nucleon decay introduces imaginary parts in the low-energy constants of the ΔB=0 nuclear interactions in Chiral EFT. We show that up to and including next-to-leading order the deuteron decay rate is given by the sum of the decay rates of the free proton and neutron. The first nuclear correction is expected to contribute at the few-percent level and comes with an undetermined low-energy constant. We discuss its relation to earlier potential-model calculations.

Macrophages derive from multiple sources of hematopoietic progenitors. Most macrophages require colony-stimulating factor 1 receptor (CSF1R), but some macrophages persist in the absence of CSF1R. Here, we analyzed mpeg1:GFP–expressing macrophages in csf1r-deficient zebrafish and report that embryonic macrophages emerge followed by their developmental arrest. In larvae, mpeg1+ cell numbers then increased showing two distinct types in the skin: branched, putative Langerhans cells, and amoeboid cells. In contrast, although numbers also increased in csf1r-mutants, exclusively amoeboid mpeg1+ cells were present, which we showed by genetic lineage tracing to have a non-hematopoietic origin. They expressed macrophage-associated genes, but also showed decreased phagocytic gene expression and increased epithelial-associated gene expression, characteristic of metaphocytes, recently discovered ectoderm-derived cells. We further demonstrated that juvenile csf1r-deficient zebrafish exhibit systemic macrophage depletion. Thus, csf1r deficiency disrupts embryonic to adult macrophage development. Zebrafish deficient for csf1r are viable and permit analyzing the consequences of macrophage loss throughout life.

Is vision necessary for the development of the categorical organization of the Ventral Occipito-Temporal Cortex (VOTC)? We used fMRI to characterize VOTC responses to eight categories presented acoustically in sighted and early blind individuals, and visually in a separate sighted group. We observed that VOTC reliably encodes sound categories in sighted and blind people using a representational structure and connectivity partially similar to the one found in vision. Sound categories were, however, more reliably encoded in the blind than the sighted group, using a representational format closer to the one found in vision. Crucially, VOTC in blind represents the categorical membership of sounds rather than their acoustic features. Our results suggest that sounds trigger categorical responses in the VOTC of congenitally blind and sighted people that partially match the topography and functional profile of the visual response, despite qualitative nuances in the categorical organization of VOTC between modalities and groups.