Structural basis of NINJ1-mediated plasma membrane rupture in cell death.

Eukaryotic cells can undergo different forms of programmed cell death, many of which culminate in plasma membrane rupture as the defining terminal event1-7. Plasma membrane rupture was long thought to be driven by osmotic pressure, but it has recently been shown to be in many cases an active process, mediated by the protein ninjurin-18 (NINJ1). Here we resolve the structure of NINJ1 and the mechanism by which it ruptures membranes. Super-resolution microscopy reveals that NINJ1 clusters into structurally diverse assemblies in the membranes of dying cells, in particular large, filamentous assemblies with branched morphology. A cryo-electron microscopy structure of NINJ1 filaments shows a tightly packed fence-like array of transmembrane α-helices. Filament directionality and stability is defined by two amphipathic α-helices that interlink adjacent filament subunits. The NINJ1 filament features a hydrophilic side and a hydrophobic side, and molecular dynamics simulations show that it can stably cap membrane edges. The function of the resulting supramolecular arrangement was validated by site-directed mutagenesis. Our data thus suggest that, during lytic cell death, the extracellular α-helices of NINJ1 insert into the plasma membrane to polymerize NINJ1 monomers into amphipathic filaments that rupture the plasma membrane. The membrane protein NINJ1 is therefore an interactive component of the eukaryotic cell membrane that functions as an in-built breaking point in response to activation of cell death.

NINJ1 induces plasma membrane rupture and release of damage-associated molecular pattern molecules during ferroptosis.

Ferroptosis is a regulated form of necrotic cell death caused by iron-dependent accumulation of oxidized phospholipids in cellular membranes, culminating in plasma membrane rupture (PMR) and cell lysis. PMR is also a hallmark of other types of programmed necrosis, such as pyroptosis and necroptosis, where it is initiated by dedicated pore-forming cell death-executing factors. However, whether ferroptosis-associated PMR is also actively executed by proteins or driven by osmotic pressure remains unknown. Here, we investigate a potential ferroptosis role of ninjurin-1 (NINJ1), a recently identified executor of pyroptosis-associated PMR. We report that NINJ1 oligomerizes during ferroptosis, and that Ninj1-deficiency protects macrophages and fibroblasts from ferroptosis-associated PMR. Mechanistically, we find that NINJ1 is dispensable for the initial steps of ferroptosis, such as lipid peroxidation, channel-mediated calcium influx, and cell swelling. In contrast, NINJ1 is required for early loss of plasma membrane integrity, which precedes complete PMR. Furthermore, NINJ1 mediates the release of cytosolic proteins and danger-associated molecular pattern (DAMP) molecules from ferroptotic cells, suggesting that targeting NINJ1 could be a therapeutic option to reduce ferroptosis-associated inflammation.

Ferritin heavy chain supports stability and function of the regulatory T cell lineage.

Regulatory T (TREG) cells develop via a program orchestrated by the transcription factor forkhead box protein P3 (FOXP3). Maintenance of the TREG cell lineage relies on sustained FOXP3 transcription via a mechanism involving demethylation of cytosine-phosphate-guanine (CpG)-rich elements at conserved non-coding sequences (CNS) in the FOXP3 locus. This cytosine demethylation is catalyzed by the ten-eleven translocation (TET) family of dioxygenases, and it involves a redox reaction that uses iron (Fe) as an essential cofactor. Here, we establish that human and mouse TREG cells express Fe-regulatory genes, including that encoding ferritin heavy chain (FTH), at relatively high levels compared to conventional T helper cells. We show that FTH expression in TREG cells is essential for immune homeostasis. Mechanistically, FTH supports TET-catalyzed demethylation of CpG-rich sequences CNS1 and 2 in the FOXP3 locus, thereby promoting FOXP3 transcription and TREG cell stability. This process, which is essential for TREG lineage stability and function, limits the severity of autoimmune neuroinflammation and infectious diseases, and favors tumor progression. These findings suggest that the regulation of intracellular iron by FTH is a stable property of TREG cells that supports immune homeostasis and limits the pathological outcomes of immune-mediated inflammation.

Measuring the α-particle charge radius with muonic helium-4 ions.

The energy levels of hydrogen-like atomic systems can be calculated with great precision. Starting from their quantum mechanical solution, they have been refined over the years to include the electron spin, the relativistic and quantum field effects, and tiny energy shifts related to the complex structure of the nucleus. These energy shifts caused by the nuclear structure are vastly magnified in hydrogen-like systems formed by a negative muon and a nucleus, so spectroscopy of these muonic ions can be used to investigate the nuclear structure with high precision. Here we present the measurement of two 2S-2P transitions in the muonic helium-4 ion that yields a precise determination of the root-mean-square charge radius of the α particle of 1.67824(83) femtometres. This determination from atomic spectroscopy is in excellent agreement with the value from electron scattering1, but a factor of 4.8 more precise, providing a benchmark for few-nucleon theories, lattice quantum chromodynamics and electron scattering. This agreement also constrains several beyond-standard-model theories proposed to explain the proton-radius puzzle2-5, in line with recent determinations of the proton charge radius6-9, and establishes spectroscopy of light muonic atoms and ions as a precise tool for studies of nuclear properties.

Efficacy and Safety of Remdesivir in People With Impaired Kidney Function Hospitalized for COVID-19 Pneumonia: A Randomized Clinical Trial.

BACKGROUND: Few antiviral therapies have been studied in patients with COVID-19 and kidney impairment. Herein, efficacy, safety, and pharmacokinetics of remdesivir, its metabolites, and sulfobutylether-beta-cyclodextrin excipient were evaluated in hospitalized patients with COVID-19 and severe kidney impairment. METHODS: In REDPINE, a phase 3, randomized, double-blind, placebo-controlled study, participants aged ≥12 years hospitalized for COVID-19 pneumonia with acute kidney injury (AKI), chronic kidney disease (CKD), or kidney failure were randomized 2:1 to receive intravenous remdesivir (200 mg on Day 1; 100 mg daily up to Day 5) or placebo (enrollment: March 2021-March 2022). The primary efficacy endpoint was the composite of all-cause mortality or invasive mechanical ventilation (IMV) through Day 29. Safety was evaluated through Day 60. RESULTS: Although enrollment concluded early, 243 participants were enrolled and treated (remdesivir, n = 163; placebo, n = 80). At baseline, 90 (37.0%) participants had AKI (remdesivir, 60; placebo, 30), 64 (26.3%) had CKD (remdesivir, 44; placebo, 20), and 89 (36.6%) had kidney failure (remdesivir, 59; placebo, 30); 31 (12.8%) were COVID-19 vaccinated. Composite all-cause mortality or IMV through Day 29 was 29.4% and 32.5% in the remdesivir and placebo group, respectively (P = 0.61). Treatment-emergent adverse events were reported in 80.4% versus 77.5% and serious adverse events in 50.3% versus 50.0% of participants who received remdesivir versus placebo, respectively. Pharmacokinetic plasma exposure to remdesivir was not affected by kidney function. CONCLUSIONS: Although underpowered, no significant difference in efficacy was observed between treatment groups. REDPINE demonstrated that remdesivir is safe in those with COVID-19 and severe kidney impairment. (EudraCT number: 2020-005416-22; Clinical Trials.gov number: NCT04745351). TRIAL REGISTRATION: EudraCT number: 2020-005416-22; Clinical Trials.gov number: NCT04745351.

Current Knowledge About the Impact of Maternal and Infant Nutrition on the Development of the Microbiota-Gut-Brain Axis.

The prenatal and early postnatal periods are stages during which dynamic changes and the development of the brain and gut microbiota occur, and nutrition is one of the most important modifiable factors that influences this process. Given the bidirectional cross talk between the gut microbiota and the brain through the microbiota-gut-brain axis (MGBA), there is growing interest in evaluating the potential effects of nutritional interventions administered during these critical developmental windows on gut microbiota composition and function and their association with neurodevelopmental outcomes. We review recent preclinical and clinical evidence from animal studies and infant/child populations. Although further research is needed, growing evidence suggests that different functional nutrients affect the establishment and development of the microbiota-gut-brain axis and could have preventive and therapeutic use in the treatment of neuropsychiatric disorders. Therefore, more in-depth knowledge regarding the effect of nutrition on the MGBA during critical developmental windows may enable the prevention of later neurocognitive and behavioral disorders and allow the establishment of individualized nutrition-based programs that can be used from the prenatal to the early and middle stages of life.

The radiation of nodulated Chamaecrista species from the rainforest into more diverse habitats has been accompanied by a reduction in growth form and a shift from fixation threads to symbiosomes.

All non-Mimosoid nodulated genera in the legume subfamily Caesalpinioideae confine their rhizobial symbionts within cell wall-bound 'fixation threads' (FTs). The exception is the large genus Chamaecrista in which shrubs and subshrubs house their rhizobial bacteroids more intimately within symbiosomes, whereas large trees have FTs. This study aimed to unravel the evolutionary relationships between Chamaecrista growth habit, habitat, nodule bacteroid type, and rhizobial genotype. The growth habit, bacteroid anatomy, and rhizobial symbionts of 30 nodulated Chamaecrista species native to different biomes in the Brazilian state of Bahia, a major centre of diversity for the genus, was plotted onto an ITS-trnL-F-derived phylogeny of Chamaecrista. The bacteroids from most of the Chamaecrista species examined were enclosed in symbiosomes (SYM-type nodules), but those in arborescent species in the section Apoucouita, at the base of the genus, were enclosed in cell wall material containing homogalacturonan (HG) and cellulose (FT-type nodules). Most symbionts were Bradyrhizobium genotypes grouped according to the growth habits of their hosts, but the tree, C. eitenorum, was nodulated by Paraburkholderia. Chamaecrista has a range of growth habits that allow it to occupy several different biomes and to co-evolve with a wide range of (mainly) bradyrhizobial symbionts. FTs represent a less intimate symbiosis linked with nodulation losses, so the evolution of SYM-type nodules by most Chamaecrista species may have (i) aided the genus-wide retention of nodulation, and (ii) assisted in its rapid speciation and radiation out of the rainforest into more diverse and challenging habitats.

Controllable Structural Transformation of Non-Porous Propyl-Malonate Hexakis[60]fullerene by Chloroform Uptake/Release.

The design of dynamic structures with high recognition host-guest materials capable to host selectively small volatile molecules is an emergent field of research with both fundamental and applied implications. The challenge of exploring novel materials with advanced functionalities has led to the development of dynamic crystalline structures promoted by soft interactions. Here, a new pure organic dynamic framework based on hexakis[60]fullerene that are held together by weak van der Waals interactions is described. This crystalline structure is capable of absorbing and releasing chloroform, through internal structural reorganization. This research provides new insight into the design of organic molecular crystals for selective adsorption applications.

Variation of subclinical psychosis across 16 sites in Europe and Brazil: findings from the multi-national EU-GEI study.

BACKGROUND: Incidence of first-episode psychosis (FEP) varies substantially across geographic regions. Phenotypes of subclinical psychosis (SP), such as psychotic-like experiences (PLEs) and schizotypy, present several similarities with psychosis. We aimed to examine whether SP measures varied across different sites and whether this variation was comparable with FEP incidence within the same areas. We further examined contribution of environmental and genetic factors to SP. METHODS: We used data from 1497 controls recruited in 16 different sites across 6 countries. Factor scores for several psychopathological dimensions of schizotypy and PLEs were obtained using multidimensional item response theory models. Variation of these scores was assessed using multi-level regression analysis to estimate individual and between-sites variance adjusting for age, sex, education, migrant, employment and relational status, childhood adversity, and cannabis use. In the final model we added local FEP incidence as a second-level variable. Association with genetic liability was examined separately. RESULTS: Schizotypy showed a large between-sites variation with up to 15% of variance attributable to site-level characteristics. Adding local FEP incidence to the model considerably reduced the between-sites unexplained schizotypy variance. PLEs did not show as much variation. Overall, SP was associated with younger age, migrant, unmarried, unemployed and less educated individuals, cannabis use, and childhood adversity. Both phenotypes were associated with genetic liability to schizophrenia. CONCLUSIONS: Schizotypy showed substantial between-sites variation, being more represented in areas where FEP incidence is higher. This supports the hypothesis that shared contextual factors shape the between-sites variation of psychosis across the spectrum.

Exploring the mediation of DNA methylation across the epigenome between childhood adversity and First Episode of Psychosis-findings from the EU-GEI study.

ABTRACT: Studies conducted in psychotic disorders have shown that DNA-methylation (DNAm) is sensitive to the impact of Childhood Adversity (CA). However, whether it mediates the association between CA and psychosis is yet to be explored. Epigenome wide association studies (EWAS) using the Illumina Infinium-Methylation EPIC array in peripheral blood tissue from 366 First-episode of psychosis and 517 healthy controls was performed. Adversity scores were created for abuse, neglect and composite adversity with the Childhood Trauma Questionnaire (CTQ). Regressions examining (I) CTQ scores with psychosis; (II) with DNAm EWAS level and (III) between DNAm and caseness, adjusted for a variety of confounders were conducted. Divide-Aggregate Composite-null Test for the composite null-hypothesis of no mediation effect was conducted. Enrichment analyses were conducted with missMethyl package and the KEGG database. Our results show that CA was associated with psychosis (Composite: OR = 1.68; p = <0.001; abuse: OR = 2.16; p < 0.001; neglect: OR = 2.27; p = <0.001). None of the CpG sites significantly mediated the adversity-psychosis association after Bonferroni correction (p < 8.1 × 10-8). However, 28, 34 and 29 differentially methylated probes associated with 21, 27, 20 genes passed a less stringent discovery threshold (p < 5 × 10-5) for composite, abuse and neglect respectively, with a lack of overlap between abuse and neglect. These included genes previously associated to psychosis in EWAS studies, such as PANK1, SPEG TBKBP1, TSNARE1 or H2R. Downstream gene ontology analyses did not reveal any biological pathways that survived false discovery rate correction. Although at a non-significant level, DNAm changes in genes previously associated with schizophrenia in EWAS studies may mediate the CA-psychosis association. These results and associated involved processes such as mitochondrial or histaminergic disfunction, immunity or neural signalling requires replication in well powered samples. The lack of overlap between mediating genes associated with abuse and neglect suggests differential biological trajectories linking CA subtypes and psychosis.

Inhibitors of gastric acid secretion increase oxidative stress and matrix metalloproteinase-2 activity leading to vascular remodeling.

The use of inhibitors of gastric acid secretion (IGAS), especially proton pump inhibitors (PPI), has been associated with increased cardiovascular risk. While the mechanisms involved are not known, there is evidence supporting increased oxidative stress, a major activator of matrix metalloproteinases (MMP), as an important player in such effect. However, there is no study showing whether other IGAS such as histamine H2-receptor blockers (H2RB) cause similar effects. This study aimed at examining whether treatment with the H2RB ranitidine promotes oxidative stress resulting in vascular MMP activation and corresponding functional and structural alterations in the vasculature, as compared with those found with the PPI omeprazole. Male Wistar rats were treated (4 weeks) with vehicle (2% tween 20), omeprazole (10 mg/Kg/day; i.p.) or ranitidine (100 mg/Kg/day; gavage). Then the aorta was collected to perform functional, biochemical, and morphometric analysis. Both ranitidine and omeprazole increased gastric pH and oxidative stress assessed in situ with the fluorescent dye dihydroethidium (DHE) and with lucigenin chemiluminescence assay. Both IGAS augmented vascular activated MMP-2. These findings were associated with aortic remodeling (increased media/lumen ratio and number of cells/µm2). Both IGAS also impaired the endothelium-dependent relaxation induced by acetylcholine (isolated aortic ring preparation). This study provides evidence that the H2RB ranitidine induces vascular dysfunction, redox alterations, and remodeling similar to those found with the PPI omeprazole. These findings strongly suggest that IGAS increase oxidative stress and matrix metalloproteinase-2 activity leading to vascular remodeling, which helps to explain the increased cardiovascular risk associated with the use of those drugs.

Microbacterium memoriense sp. nov., a member of the Actinomycetota from marine beach sediment of the north coast of Portugal.

The oceans harbour a myriad of unknown micro-organisms that remain unstudied because of a failure to establish the right growth conditions under laboratory conditions. To overcome this limitation, an isolation effort inspired by the iChip was performed using marine sediments from Memória beach, Portugal. A novel strain, PMIC_1C1BT, was obtained and subjected to a polyphasic study. Cells of strain PMIC_1C1BT were Gram-positive, rod-shaped, divided by binary fission and formed colonies that were shiny light-yellow. Based on its full 16S rRNA gene sequence, strain PMIC_1C1BT was phylogenetically associated to the genus Microbacterium and its closest relatives were Microbacterium aurum KACC 15219T (98.55 %), Microbacterium diaminobutyricum RZ63T (98.48 %) and Microbacterium hatanonis JCM 14558T (98.13 %). Strain PMIC_1C1BT had a genome size of 2 761 607 bp with 67.71 mol% of G+C content and 2582 coding sequences, which is lower than the genus average. Strain PMIC_1C1BT grew from 15 to 30 °C, optimally at 25 °C, at pH 6.0 to 11.0, optimally between pH 6.0 and 8.0, and from 0 to 5 % (w/v) NaCl, optimally between 2.0 and 3.0 %. It grew with casamino acids, glutamine, methionine, N-acetylglucosamine, sodium nitrate, tryptophan, urea and valine as sole nitrogen sources, and arabinose and cellobiose as sole carbon sources. The major cellular fatty acids were anteiso-C15 : 0, iso-C16 : 0 and iso-C17 : 0. Genome mining revealed the presence of four biosynthetic gene clusters (BGCs) with low similarities to other known BCGs. Based on the polyphasic data, strain PMIC_1C1BT is proposed to represent a novel species, for which the name Microbacterium memoriense sp. nov. (=CECT 30366T=LMG 32350T) is proposed.

Unveiling the bioactive potential of Actinomycetota from the Tagus River estuary.

The increase in global travel and the incorrect and excessive use of antibiotics has led to an unprecedented rise in antibiotic resistance in bacterial and fungal populations. To overcome these problems, novel bioactive natural products must be discovered, which may be found in underexplored environments, such as estuarine habitats. In the present work, estuarine actinomycetotal strains were isolated with conventional and iChip techniques from the Tagus estuary in Alcochete, Portugal, and analysed for different antimicrobial bioactivities. Extracts were produced from the isolated cultures and tested for bioactivity against Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922, Aspergillus fumigatus ATCC 240305, Candida albicans ATCC 10231 and Trichophyton rubrum FF5. Furthermore, bioactive extracts were subjected to dereplication by high-performance liquid chromatography (HPLC) and high-resolution mass spectrometry (HRMS) to putatively identify their chemical components. In total, 105 isolates belonging to 3 genera were obtained. One which was isolated, MTZ3.1 T, represents a described novel taxon for which the name Streptomyces meridianus was proposed. Regarding the bioactivity testing, extracts from 12 strains proved to be active against S. aureus, 2 against E. coli, 4 against A. fumigatus, 3 against C. albicans and 10 against T. rubrum. Dereplication of bioactive extracts showed the presence of 28 known bioactive molecules, 35 hits have one or more possible matches in the DNP and 18 undescribed ones. These results showed that the isolated bacteria might be the source of new bioactive natural products.

Rerouting cardiovascular management following gastric bypass surgery: Dose optimization of carvedilol using population-based analysis.

AIMS: A population-based pharmacokinetic (PK) modeling approach (PopPK) was used to investigate the impact of Roux-en-Y gastric bypass (RYGB) on the PK of (R)- and (S)-carvedilol. We aimed to optimize carvedilol dosing for these patients utilizing a pharmacokinetic/pharmacodynamic (PK/PD) link model. METHODS: PopPK models were developed utilizing data from 52 subjects, including nonobese, obese, and post- RYGB patients who received rac- carvedilol orally. Covariate analysis included anthropometric and laboratory data, history of RYGB surgery, CYP2D6 and CYP3A4 in vivo activity, and relative intestinal abundance of major drug- metabolizing enzymes and transporters. A direct effect inhibitory Emax pharmacodynamic model was linked to the PK model of (S)- carvedilol to simulate the changes in exercise- induced heart rate. RESULTS: A 2-compartmental model with linear elimination and parallel first-order absorptions best described (S)-carvedilol PK. RYGB led to a twofold reduction in relative oral bioavailability compared to nonoperated subjects, along with delayed absorption of both enantiomers. The intestinal ABCC2 mRNA expression increases the time to reach the maximum plasma concentration. The reduced exposure (AUC) of (S)-carvedilol post-RYGB corresponded to a 33% decrease in the predicted area under the effect curve (AUEC) for the 24-hour ß-blocker response. Simulation results suggested that a 50-mg daily dose in post-RYGB patients achieved comparable AUC and AUEC to 25-mg dose in nonoperated subjects. CONCLUSION: Integrated PK/PD modeling indicated that standard dosage regimens for nonoperated subjects do not provide equivalent ß-blocking activity in RYGB patients. This study highlights the importance of personalized dosing strategies to attain desired therapeutic outcomes in this patient cohort.

Silicene growth mechanisms on Au(111) and Au(110) substrates.

Despite the remarkable theoretical applications of silicene, its synthesis remains a complex task, with epitaxial growth being one of the main routes involving depositing evaporated Si atoms onto a suitable substrate. Additionally, the requirement for a substrate to maintain the silicene stability poses several difficulties in accurately determining the growth mechanisms and the resulting structures, leading to conflicting results in the literature. In this study, large-scale molecular dynamics simulations are performed to uncover the growth mechanisms and characteristics of epitaxially grown silicene sheets on Au(111) and Au(110) substrates, considering different temperatures and Si deposition rates. The growth process has been found to initiate with the nucleation of several independent islands homogeneously distributed on the substrate surface, which gradually merge to form a complete silicene sheet. The results consistently demonstrate the presence of a buckled silicene structure, although this characteristic is notably reduced when using an Au(111) substrate. Furthermore, the analysis also focuses on the quality and growth mode of the silicene sheets, considering the influence of temperature and deposition rate. The findings reveal a prevalence of the Frank-van der Merwe growth mode, along with diverse forms of defects throughout the sheets.

EBUS-TBNA for mediastinal staging of centrally located T1N0M0 non-small cell lung cancer clinically staged with PET/CT.

BACKGROUND AND OBJECTIVE: To evaluate the diagnostic accuracy and clinical usefulness of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for mediastinal staging of centrally located T1N0M0 non-small cell lung cancer (NSCLC) clinically staged with positron emission tomography/computed tomography (PET/CT). METHODS: We conducted a study that included patients with centrally located T1N0M0 NSCLC, clinically staged with PET/CT who underwent EBUS-TBNA for mediastinal staging. Patients with negative EBUS-TBNA underwent mediastinoscopy, video-assisted mediastinoscopic lymphadenectomy (VAMLA) and/or lung resection with systematic nodal dissection, that were considered the gold standard. The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), overall accuracy of EBUS-TBNA for diagnosing mediastinal metastases (N2 disease) and the number needed to treat (NNT: number of patients needed to undergo EBUS-TBNA to avoid a case of pathologic N2 disease after resection) were calculated. RESULTS: One-hundred eighteen patients were included. EBUS-TBNA proved N2 disease in four patients. In the remaining 114 patients who underwent mediastinoscopy, VAMLA and/or resection there were two cases of N2 (N2 prevalence 5.1%). The sensitivity, specificity, NPV, PPV and overall accuracy for diagnosing mediastinal metastases (N2 disease) were of 66%, 100%, 98%, 100% and 98%, respectively. The NNT was 31 (95% CI: 15-119). CONCLUSION: EBUS-TBNA in patients with central clinically staged T1N0M0 NSCLC presents a good diagnostic accuracy for mediastinal staging, even in a population with low prevalence of N2 disease. Therefore, its indication should be considered in the management of even these early lung cancers.

Potential of Ocotea indecora (Schott) Mez essential oil nanoemulsion in schistosomiasis control: Molluscicidal effects.

Schistosomiasis is a neglected disease transmitted through contaminated water in populations with low basic sanitation. The World Health Organization recommends controlling the intermediate host snails of the Biomphalaria genus with the molluscicide niclosamide. This work aims to evaluate the biocidal potential of the nanoemulsion prepared with the essential oil of Ocotea indecora leaves for the control of the mollusk Biomphalaria glabrata, intermediate host of the Schistosoma mansoni, the etiologic agent of schistosomiasis.

Dual-task training is as effective as functional training on the functional fitness of older women: a randomized clinical trial.

BACKGROUND: The interest in approaches that improve older individuals' functional fitness and autonomy is increasing. However, the effects of dual-task training on older women's functional fitness and the comparison with the functional training approach are unclear. Therefore, we compared dual-task and functional training on the functional fitness of older women and the effects of three months of detraining. METHODS: Sixty-one women performed 16 weeks of dual-task training or functional training. The functional fitness was measured pre-, post-training, and post-detraining, based on the ability to put on and take off a t-shirt, evaluating the mobility of the upper limb, standing-up from the prone position measuring the global functionality, five times sit-to-stand test to assess the lower limbs muscle power, timed up and go to measure the dynamic balance and agility, gallon-jug shelf-transfer to evaluate the global functionality emphasizing the upper limbs and 10 m walk test to analyze the gait ability. RESULTS: Dual-task training and functional training generally provided significant small to moderate magnitude performance increases in the put on and take off a t-shirt (dual-task training: d = 0.35 / functional training: d = 0.49), five times sit-to-stand test (dual-task training: d = 0.41 / functional training: d = 0.77), timed up and go (dual-task training: d = 0.34 / functional training: d = 0.78), and gallon-jug shelf-transfer (dual-task training: d = 0.76 / functional training: d = 0.82). Only the functional training improved the 10 m walk test (d = 0.32; p = 0.013), and both groups did not change the standing-up from the prone position performance. After the detraining period, both groups kept the adaptations for the gallon-jug shelf-transfer and five times sit-to-stand test. At the same time, only the dual-task training maintained the adaptations for the put on and take off a t-shirt and the functional training for the timed up and go. CONCLUSION: Sixteen weeks of dual-task and functional training are similarly effective in improving older women's functional fitness, maintaining their benefits even after three months of detraining. TRIAL REGISTRATION: RBR-10ny848z ( https://ensaiosclinicos.gov.br/rg/RBR-10ny848z ).

Consistency of dry matter intake in Holstein cows: Heritability estimates and associations with feed efficiency.

Resilience can be defined as the capacity to maintain performance or bounce back to normal functioning after a perturbation, and studying fluctuations in daily feed intake may be an effective way to identify resilient dairy cows. Our goal was to develop new phenotypes based on daily dry matter intake (DMI) consistency in Holstein cows, estimate genetic parameters and genetic correlations with feed efficiency and milk yield consistency, and evaluate their relationships with production, longevity, health, and reproduction traits. Data consisted of 397,334 daily DMI records of 6,238 lactating Holstein cows collected from 2007 to 2022 at 6 research stations across the United States. Consistency phenotypes were calculated based on the deviations from expected daily DMI for individual cows during their respective feeding trials, which ranged from 27 to 151 d in duration. Expected values were derived from different models, including simple average, quadratic and cubic quantile regression with a 0.5 quantile, and locally estimated scatterplot smoothing (LOESS) regression with span parameters 0.5 and 0.7. We then calculated the log of variance (log-Var-DMI) of daily deviations for each model as the consistency phenotype. Consistency of milk yield was also calculated, as a reference, using the same methods (log-Var-Milk). Genetic parameters were estimated using an animal model, including lactation, days in milk and cohort as fixed effects, and animal as random effect. Relationships between log-Var-DMI and traits currently considered in the US national genetic evaluation were evaluated using Spearman's rank correlations between sires' breeding values. Heritability estimates for log-Var-DMI ranged from 0.11 ± 0.02 to 0.14 ± 0.02 across models. Different methods (simple average, quantile regressions, and LOESS regressions) used to calculate log-Var-DMI yielded very similar results, with genetic correlations ranging from 0.94 to 0.99. Estimated genetic correlations between log-Var-DMI and log-Var-Milk ranged from 0.51 to 0.62. Estimated genetic correlations between log-Var-DMI and feed efficiency ranged from 0.55 to 0.60 with secreted milk energy, from 0.59 to 0.63 with metabolic body weight, and from 0.26 to 0.31 with residual feed intake (RFI). Relationships between log-Var-DMI and the traits in the national genetic evaluation were moderate and positive correlations with milk yield (0.20 to 0.21), moderate and negative correlations with female fertility (-0.07 to -0.20), no significant correlations with health and longevity, and favorable correlations with feed efficiency (-0.23 to -0.25 with feed saved and 0.21 to 0.26 with RFI). We concluded that DMI consistency is heritable and may be an indicator of resilience. Cows with lower variation in the difference between actual and expected daily DMI (more consistency) may be more effective in maintaining performance in the face of challenges or perturbations, whereas cows with greater variation in observed versus expected daily DMI (less consistency) are less feed efficient and may be less resilient.

Investigating relationships between the host genome, rumen microbiome, and dairy cow feed efficiency using mediation analysis with structural equation modeling.

The rumen microbiome is crucial for converting feed into absorbable nutrients used for milk synthesis, and the efficiency of this process directly impacts the profitability and sustainability of the dairy industry. Recent studies have found that the rumen microbial composition explains part of the variation in feed efficiency traits, including dry matter intake, milk energy, and residual feed intake. The main goal of this study was to reveal relationships between the host genome, rumen microbiome, and dairy cow feed efficiency using structural equation models. Our specific objectives were to (i) infer the mediation effects of the rumen microbiome on feed efficiency traits, (ii) estimate the direct and total heritability of feed efficiency traits, and (iii) calculate the direct and total breeding values of feed efficiency traits. Data consisted of dry matter intake, milk energy, and residual feed intake records, SNP genotype data, and 16S rRNA rumen microbial abundances from 448 mid-lactation Holstein cows from 2 research farms. We implemented structural equation models such that the host genome directly affects the phenotype (GP → P) and the rumen microbiome (GM → P), while the microbiome affects the phenotype (M → P), partially mediating the effect of the host genome on the phenotype (G → M → P). We found that 7 to 30% of microbes within the rumen microbial community had structural coefficients different from zero. We classified these microbes into 3 groups that could have different uses in dairy farming. Microbes with heritability <0.10 but significant causal effects on feed efficiency are attractive for external interventions. On the other hand, 2 groups of microbes with heritability ≥0.10, significant causal effects, and genetic covariances and causal effects with the same or opposite sign to feed efficiency are attractive for selective breeding, improving or decreasing the trait heritability and response to selection, respectively. In general, the inclusion of the different microbes in genomic models tends to decrease the trait heritability rather than increase it, ranging from -15% to +5%, depending on the microbial group and phenotypic trait. Our findings provide more understanding to target rumen microbes that can be manipulated, either through selection or management interventions, to improve feed efficiency traits.