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1.
Nature ; 627(8004): 522-527, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38509277

RESUMEN

Topological whirls or 'textures' of spins such as magnetic skyrmions represent the smallest realizable emergent magnetic entities1-5. They hold considerable promise as robust, nanometre-scale, mobile bits for sustainable computing6-8. A longstanding roadblock to unleashing their potential is the absence of a device enabling deterministic electrical readout of individual spin textures9,10. Here we present the wafer-scale realization of a nanoscale chiral magnetic tunnel junction (MTJ) hosting a single, ambient skyrmion. Using a suite of electrical and multimodal imaging techniques, we show that the MTJ nucleates skyrmions of fixed polarity, whose large readout signal-20-70% relative to uniformly magnetized states-corresponds directly to skyrmion size. The MTJ exploits complementary nucleation mechanisms to stabilize distinctly sized skyrmions at zero field, thereby realizing three non-volatile electrical states. Crucially, it can electrically write and delete skyrmions to both uniform states with switching energies 1,000 times lower than the state of the art. Here, the applied voltage emulates a magnetic field and, in contrast to conventional MTJs, it reshapes both the energetics and kinetics of the switching transition, enabling deterministic bidirectional switching. Our stack platform enables large readout and efficient switching, and is compatible with lateral manipulation of skyrmionic bits, providing the much-anticipated backbone for all-electrical skyrmionic device architectures9,10. Its wafer-scale realizability provides a springboard to harness chiral spin textures for multibit memory and unconventional computing8,11.

2.
Nat Immunol ; 17(8): 906-13, 2016 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-27434011

RESUMEN

Inflammation occurs after disruption of tissue homeostasis by cell stress, injury or infection and ultimately involves the recruitment and retention of cells of hematopoietic origin, which arrive at the affected sites to resolve damage and initiate repair. Interleukin 1α (IL-1α) and IL-1ß are equally potent inflammatory cytokines that activate the inflammatory process, and their deregulated signaling causes devastating diseases manifested by severe acute or chronic inflammation. Although much attention has been given to understanding the biogenesis of IL-1ß, the biogenesis of IL-1α and its distinctive role in the inflammatory process remain poorly defined. In this review we examine key aspects of IL-1α biology and regulation and discuss its emerging importance in the initiation and maintenance of inflammation that underlie the pathology of many human diseases.


Asunto(s)
Inflamación/fisiopatología , Interleucina-1alfa/fisiología , Alarminas/metabolismo , Animales , Membrana Celular/metabolismo , Regulación de la Expresión Génica , Granuloma/etiología , Granuloma/metabolismo , Humanos , Inflamación/metabolismo , Interleucina-1alfa/biosíntesis , Interleucina-1alfa/genética , Macrófagos/fisiología , Ratones , Ratones Endogámicos BALB C , Modelos Biológicos , Neoplasias/etiología , Neoplasias/metabolismo , Neoplasias/fisiopatología , Unión Proteica , Biosíntesis de Proteínas , Procesamiento Proteico-Postraduccional , Receptores de Interleucina-1/fisiología , Transducción de Señal
3.
Immunity ; 49(1): 42-55.e6, 2018 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-30021146

RESUMEN

The execution of shock following high dose E. coli lipopolysaccharide (LPS) or bacterial sepsis in mice required pro-apoptotic caspase-8 in addition to pro-pyroptotic caspase-11 and gasdermin D. Hematopoietic cells produced MyD88- and TRIF-dependent inflammatory cytokines sufficient to initiate shock without any contribution from caspase-8 or caspase-11. Both proteases had to be present to support tumor necrosis factor- and interferon-ß-dependent tissue injury first observed in the small intestine and later in spleen and thymus. Caspase-11 enhanced the activation of caspase-8 and extrinsic cell death machinery within the lower small intestine. Neither caspase-8 nor caspase-11 was individually sufficient for shock. Both caspases collaborated to amplify inflammatory signals associated with tissue damage. Therefore, combined pyroptotic and apoptotic signaling mediated endotoxemia independently of RIPK1 kinase activity and RIPK3 function. These observations bring to light the relevance of tissue compartmentalization to disease processes in vivo where cytokines act in parallel to execute diverse cell death pathways.


Asunto(s)
Caspasa 8/metabolismo , Caspasas/metabolismo , Infecciones por Escherichia coli/enzimología , Infecciones por Escherichia coli/fisiopatología , Choque Séptico/enzimología , Choque Séptico/fisiopatología , Animales , Apoptosis , Proteínas Reguladoras de la Apoptosis/metabolismo , Caspasa 8/genética , Caspasas/genética , Caspasas Iniciadoras , Células Cultivadas , Femenino , Inflamación/metabolismo , Inflamación/patología , Factor 3 Regulador del Interferón/genética , Interferón beta/sangre , Interferón beta/metabolismo , Intestino Delgado/patología , Péptidos y Proteínas de Señalización Intracelular , Lipopolisacáridos/toxicidad , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas de Unión a Fosfato , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Transducción de Señal , Bazo/patología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/sangre , Factor de Necrosis Tumoral alfa/metabolismo
4.
Nature ; 568(7752): 368-372, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30996320

RESUMEN

Complex topological configurations are fertile ground for exploring emergent phenomena and exotic phases in condensed-matter physics. For example, the recent discovery of polarization vortices and their associated complex-phase coexistence and response under applied electric fields in superlattices of (PbTiO3)n/(SrTiO3)n suggests the presence of a complex, multi-dimensional system capable of interesting physical responses, such as chirality, negative capacitance and large piezo-electric responses1-3. Here, by varying epitaxial constraints, we discover room-temperature polar-skyrmion bubbles in a lead titanate layer confined by strontium titanate layers, which are imaged by atomic-resolution scanning transmission electron microscopy. Phase-field modelling and second-principles calculations reveal that the polar-skyrmion bubbles have a skyrmion number of +1, and resonant soft-X-ray diffraction experiments show circular dichroism, confirming chirality. Such nanometre-scale polar-skyrmion bubbles are the electric analogues of magnetic skyrmions, and could contribute to the advancement of ferroelectrics towards functionalities incorporating emergent chirality and electrically controllable negative capacitance.

5.
Mol Ther ; 32(1): 103-123, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-37919899

RESUMEN

Targeted delivery and cell-type-specific expression of gene-editing proteins in various cell types in vivo represent major challenges for all viral and non-viral delivery platforms developed to date. Here, we describe the development and analysis of artificial vectors for intravascular delivery (AVIDs), an engineered adenovirus-based gene delivery platform that allows for highly targeted, safe, and efficient gene delivery to human hematopoietic stem and progenitor cells (HSPCs) in vivo after intravenous vector administration. Due to a set of refined structural modifications, intravenous administration of AVIDs did not trigger cytokine storm, hepatotoxicity, or thrombocytopenia. Single intravenous administration of AVIDs to humanized mice, grafted with human CD34+ cells, led to up to 20% transduction of CD34+CD38-CD45RA- HSPC subsets in the bone marrow. Importantly, targeted in vivo transduction of CD34+CD38-CD45RA-CD90-CD49f+ subsets, highly enriched for human hematopoietic stem cells (HSCs), reached up to 19%, which represented a 1,900-fold selectivity in gene delivery to HSC-enriched over lineage-committed CD34-negative cell populations. Because the AVID platform allows for regulated, cell-type-specific expression of gene-editing technologies as well as expression of immunomodulatory proteins to ensure persistence of corrected HSCs in vivo, the HSC-targeted AVID platform may enable development of curative therapies through in vivo gene correction in human HSCs after a single intravenous administration.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas , Humanos , Animales , Ratones , Células Madre Hematopoyéticas/metabolismo , Técnicas de Transferencia de Gen , Antígenos CD34/metabolismo , Terapia Genética , Adenoviridae/genética , Adenoviridae/metabolismo
6.
PLoS Genet ; 18(3): e1010024, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35239675

RESUMEN

Genetic mechanisms that repress transposable elements (TEs) in young animals decline during aging, as reflected by increased TE expression in aged animals. Does increased TE expression during aging lead to more genomic TE copies in older animals? To address this question, we quantified TE Landscapes (TLs) via whole genome sequencing of young and aged Drosophila strains of wild-type and mutant backgrounds. We quantified TLs in whole flies and dissected brains and validated the feasibility of our approach in detecting new TE insertions in aging Drosophila genomes when small RNA and RNA interference (RNAi) pathways are compromised. We also describe improved sequencing methods to quantify extra-chromosomal DNA circles (eccDNAs) in Drosophila as an additional source of TE copies that accumulate during aging. Lastly, to combat the natural progression of aging-associated TE expression, we show that knocking down PAF1, a conserved transcription elongation factor that antagonizes RNAi pathways, may bolster suppression of TEs during aging and extend lifespan. Our study suggests that in addition to a possible influence by different genetic backgrounds, small RNA and RNAi mechanisms may mitigate genomic TL expansion despite the increase in TE transcripts during aging.


Asunto(s)
Elementos Transponibles de ADN , Drosophila , Envejecimiento/genética , Animales , Elementos Transponibles de ADN/genética , Drosophila/genética , Genómica/métodos , ARN
7.
Genome Res ; 31(3): 512-528, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33419731

RESUMEN

Although mosquitoes are major transmission vectors for pathogenic arboviruses, viral infection has little impact on mosquito health. This immunity is caused in part by mosquito RNA interference (RNAi) pathways that generate antiviral small interfering RNAs (siRNAs) and Piwi-interacting RNAs (piRNAs). RNAi also maintains genome integrity by potently repressing mosquito transposon activity in the germline and soma. However, viral and transposon small RNA regulatory pathways have not been systematically examined together in mosquitoes. Therefore, we developed an integrated mosquito small RNA genomics (MSRG) resource that analyzes the transposon and virus small RNA profiles in mosquito cell cultures and somatic and gonadal tissues across four medically important mosquito species. Our resource captures both somatic and gonadal small RNA expression profiles within mosquito cell cultures, and we report the evolutionary dynamics of a novel Mosquito-Conserved piRNA Cluster Locus (MCpiRCL) made up of satellite DNA repeats. In the larger culicine mosquito genomes we detected highly regular periodicity in piRNA biogenesis patterns coinciding with the expansion of Piwi pathway genes. Finally, our resource enables detection of cross talk between piRNA and siRNA populations in mosquito cells during a response to virus infection. The MSRG resource will aid efforts to dissect and combat the capacity of mosquitoes to tolerate and spread arboviruses.


Asunto(s)
Culicidae/genética , Culicidae/virología , Elementos Transponibles de ADN/genética , Genómica , ARN Interferente Pequeño/genética , Virus , Animales
8.
Proc Biol Sci ; 291(2026): 20240514, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38955232

RESUMEN

Caddisflies (Trichoptera) are among the most diverse groups of freshwater animals with more than 16 000 described species. They play a fundamental role in freshwater ecology and environmental engineering in streams, rivers and lakes. Because of this, they are frequently used as indicator organisms in biomonitoring programmes. Despite their importance, key questions concerning the evolutionary history of caddisflies, such as the timing and origin of larval case making, remain unanswered owing to the lack of a well-resolved phylogeny. Here, we estimated a phylogenetic tree using a combination of transcriptomes and targeted enrichment data for 207 species, representing 48 of 52 extant families and 174 genera. We calibrated and dated the tree with 33 carefully selected fossils. The first caddisflies originated approximately 295 million years ago in the Permian, and major suborders began to diversify in the Triassic. Furthermore, we show that portable case making evolved in three separate lineages, and shifts in diversification occurred in concert with key evolutionary innovations beyond case making.


Asunto(s)
Evolución Biológica , Fósiles , Insectos , Filogenia , Animales , Insectos/genética , Transcriptoma
9.
Immunity ; 43(6): 1125-36, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26682985

RESUMEN

The interleukin-1 receptor I (IL-1RI) is critical for host resistance to Mycobacterium tuberculosis (Mtb), yet the mechanisms of IL-1RI-mediated pathogen control remain unclear. Here, we show that without IL-1RI, Mtb-infected newly recruited Ly6G(hi) myeloid cells failed to upregulate tumor necrosis factor receptor I (TNF-RI) and to produce reactive oxygen species, resulting in compromised pathogen control. Furthermore, simultaneous ablation of IL-1RI and TNF-RI signaling on either stroma or hematopoietic cells led to early lethality, indicating non-redundant and synergistic roles of IL-1 and TNF in mediating macrophage-stroma cross-talk that was critical for optimal control of Mtb infection. Finally, we show that even in the presence of functional Mtb-specific adaptive immunity, the lack of IL-1α and not IL-1ß led to an exuberant intracellular pathogen replication and progressive non-resolving inflammation. Our study reveals functional interdependence between IL-1 and TNF in enabling Mtb control mechanisms that are critical for host survival.


Asunto(s)
Interleucina-1alfa/inmunología , Tuberculosis/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Animales , Separación Celular , Modelos Animales de Enfermedad , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mycobacterium tuberculosis , Receptores Tipo I de Interleucina-1/inmunología
10.
Int J Behav Med ; 31(2): 241-251, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37010798

RESUMEN

BACKGROUND: Studies have suggested that type 2 diabetes mellitus (T2DM) are at risk of self-stigmatization (i.e., internalized sense of shame about having diabetes). Self-stigma has been found to be associated with poorer psychological outcomes among chronic disease patients; relevant studies examining such an association and its psychosocial mechanisms are scarce among Chinese T2DM patients. This study aimed to examine the association between self-stigma and psychological outcomes among T2DM patients in Hong Kong. Self-stigma was hypothesized to be associated with higher psychological distress and lower quality of life (QoL). Such associations were also hypothesized to be mediated by lower perceived social support, lower self-care self-efficacy, plus higher self-perceived burden to significant others. METHODS: T2DM patients (N = 206) recruited from hospitals and clinics in Hong Kong were invited to complete a cross-sectional survey measuring the aforementioned variables. RESULTS: After controlling for covariates, multiple mediation analysis results indicated the indirect effects from self-stigma to psychological distress via increased self-perceived burden (ß = 0.07; 95% CI = 0.02, 0.15) and decreased self-care self-efficacy (ß = 0.05; 95% CI = 0.01, 0.11) were significant. Moreover, the indirect effect from self-stigma to QoL via decreased self-care self-efficacy was also significant (ß = -0.07; 95% CI = -0.14, -0.02). After considering the mediators, the direct effects from self-stigma to higher psychological distress and lower QoL remained significant (ßs = 0.15 and -0.15 respectively, ps < .05). CONCLUSIONS: Self-stigma could be linked to poorer psychological outcomes through increased self-perceived burden and decreased self-care self-efficacy among T2DM patients. Targeting those variables when designing interventions might facilitate those patients' psychological adjustments.


Asunto(s)
Diabetes Mellitus Tipo 2 , Calidad de Vida , Humanos , Calidad de Vida/psicología , Diabetes Mellitus Tipo 2/complicaciones , Hong Kong , Estudios Transversales , Estrés Psicológico/psicología , Estigma Social , Vergüenza
11.
Proteomics ; 23(16): e2200380, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37148169

RESUMEN

The use of poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs) as carriers for chemotherapeutic drugs is regarded as an actively targeted nano-therapy for the specific delivery of anti-cancer drugs to target cells. However, the exact mechanism by which PLGA NPs boost anticancer cytotoxicity at the molecular level remains largely unclear. This study employed different molecular approaches to define the response of carcinoma FaDu cells to different types of treatment, specifically: paclitaxel (PTX) alone, drug free PLGA NPs, and PTX-loaded PTX-PLGA NPs. Functional cell assays revealed that PTX-PLGA NPs treated cells had a higher level of apoptosis than PTX alone, whereas the complementary, UHPLC-MS/MS (TIMS-TOF) based multi-omics analyses revealed that PTX-PLGA NPs treatment resulted in increased abundance of proteins associated with tubulin, as well as metabolites such as 5-thymidylic acid, PC(18:1(9Z)/18:1(9Z0), vitamin D, and sphinganine among others. The multi-omics analyses revealed new insights about the molecular mechanisms underlying the action of novel anticancer NP therapies. In particular, PTX-loaded NPs appeared to exacerbate specific changes induced by both PLGA-NPs and PTX as a free drug. Hence, the PTX-PLGA NPs' molecular mode of action, seen in greater detail, depends on this synergy that ultimately accelerates the apoptotic process, resulting in cancer cell death.


Asunto(s)
Antineoplásicos , Neoplasias de Cabeza y Cuello , Nanopartículas , Humanos , Paclitaxel/farmacología , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Poliglactina 910 , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Multiómica , Espectrometría de Masas en Tándem , Ácido Poliglicólico , Ácido Láctico , Línea Celular Tumoral , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Portadores de Fármacos/farmacología
12.
Curr Diab Rep ; 23(11): 329-345, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37910312

RESUMEN

PURPOSE OF REVIEW: Interests have been emerging in using positive psychology interventions (PPIs) to improve diabetes self-management (DSM) behaviors (e.g., blood glucose monitoring, physical activity). To explore the impact of those interventions on DSM behaviors, we summarized the evidence of PPIs on self-management behaviors among both type 1 diabetes (T1D) and type 2 diabetes (T2D) patients between 2012 and 2022. RECENT FINDINGS: Among the eight studies identified, different study designs and types of PPIs were apparent. Typical PPIs (e.g., activities enhancing positive affect/gratitude/self-affirmation/optimism) were usually applied to T1D patients (N = 5); PPIs were usually combined with motivational interviewing for T2D patients (N = 3). Contrary to expectations, PPIs did not consistently demonstrate positive effects on self-management behaviors' change regardless of the types of diabetes patients, compared to the control groups. Improvements in diabetes patients' self-management behaviors from PPIs are still unclear. Future studies should more rigorously evaluate and identify the active ingredients of PPIs for behavioral changes among diabetes patients.


Asunto(s)
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Automanejo , Humanos , Diabetes Mellitus Tipo 2/terapia , Diabetes Mellitus Tipo 2/psicología , Psicología Positiva , Automanejo/psicología , Automonitorización de la Glucosa Sanguínea , Glucemia
13.
J Dairy Sci ; 106(11): 7630-7650, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37641262

RESUMEN

Objectives were to determine the effects of supplementing rumen-protected choline (RPC) on hepatic composition and secretion of triacylglycerol-rich lipoprotein when cows were subjected to feed restriction to develop fatty liver. It was hypothesized that RPC reduces hepatic triacylglycerol by enhancing secretion of hepatic lipoprotein. Pregnant, nonlactating parous Holstein cows (n = 33) at mean (± standard deviation) 234 ± 2.2 d of gestation were blocked by body condition (3.79 ± 0.49) and assigned to receive 0 g/d (CON), 25.8 g/d choline ion from a RPC product containing 28.8% choline chloride (CC; treatment L25.8), or 25.8 g/d of choline ion from a RPC product containing 60.0% CC (H25.8). Cows were fed for ad libitum intake for the first 5 d and restricted to 41% of the net energy for lactation required for maintenance and pregnancy from d 6 to 13. Intake of metabolizable methionine was maintained at 18 g/d during feed restriction by supplying rumen-protected methionine. Hepatic tissue was sampled on d 6 and 13 and analyzed for triacylglycerol and glycogen, and mRNA expression of hepatic tissue was investigated. On d 14, cows were not fed and received a 10% solution of tyloxapol intravenously at 120 mg/kg of body weight to block hydrolysis of triacylglycerols in very low density lipoprotein (VLDL). Blood was sampled sequentially for 720 min and analyzed for concentration of triacylglycerol and total cholesterol. Lymph was sampled 6 h after tyloxapol infusion, and analyzed for concentrations of fatty acids, ß-hydroxybutyrate, glucose, triacylglycerol, and total cholesterol. A sample of serum collected at 720 min after tyloxapol was assayed for the metabolome composition. The area under the curve (AUC) of serum triacylglycerol, VLDL cholesterol, and total cholesterol were calculated. Orthogonal contrasts evaluated the effect of supplementing RPC (CON vs. [1/2 L25.8 + 1/2 H25.8]) and source of RPC (L25.8 vs. H25.8). Least squares means and standard errors of the means are presented in sequence as CON, L25.8, H25.8. During feed restriction, supplementation of RPC reduced hepatic triacylglycerol (9.0 vs. 4.1 vs. 4.5 ± 0.6%) and increased glycogen contents (1.9 vs. 3.5 vs. 4.1 ± 0.2%). Similarly, supplementation of RPC increased the expression of transcripts involved in the synthesis and assembly of lipoproteins (MTTP), cellular autophagy (ATG3), and inflammation (TNFA), and reduced the expression of transcripts associated with mitochondrial oxidation of fatty acids (HADHA, MLYCD) and stabilization of lipid droplets (PLIN2). After infusion of tyloxapol, RPC increased the AUC for serum triacylglycerol (21,741 vs. 32,323 vs. 28,699 ± 3,706 mg/dL × min) and VLDL cholesterol (4,348 vs. 6,465 vs. 5,740 ± 741 mg/dL × min) but tended to reduce the concentrations of triacylglycerol in lymph (16.7 vs. 13.8 vs. 11.9 ± 1.9 mg/dL). Feeding RPC tended to increase the concentrations of 89 metabolites in serum, after adjusting for false discovery, including 3 acylcarnitines, 1 AA-related metabolite, 11 bile acids, 1 ceramide, 6 diacylglycerols, 2 dihydroceramides, 1 glycerophospholipid, and 64 triacylglycerols compared with CON. Feeding 25.8 g/d of choline ion as RPC mediated increased hepatic triacylglycerol secretion to promote lipotropic effects that reduced hepatic lipidosis in dairy cows.

14.
J Dairy Sci ; 106(2): 912-926, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36543639

RESUMEN

The objectives were to test the effects of dietary vitamin D3 [cholecalciferol (CHOL)] compared with 25-hydroxyvitamin D3 [calcidiol (CAL)] on vitamin D status and response to an endotoxin challenge. Forty-five Holstein bull calves (5 ± 2 d of age) were blocked into weekly cohorts, fed a basal diet that provided 0.25 µg/kg body weight (BW) CHOL, and assigned randomly to 1 of 5 treatments: control [(CON) no additional vitamin D], 1.5 µg/kg BW CHOL (CHOL1.5), 3 µg/kg BW CHOL (CHOL3), 1.5 µg/kg BW CAL (CAL1.5), or 3 µg/kg BW CAL (CAL3). Calves were fed milk replacer until weaning at 56 d of age and had ad libitum access to water and starter grain throughout the experiment. Treatments were added daily to the diet of milk replacer until weaning and starter grain after weaning. Measures of growth, dry matter intake, and serum concentrations of vitamin D, Ca, Mg, and P were collected from 0 to 91 d of the experiment. At 91 d of the experiment, calves received an intravenous injection of 0.1 µg/kg BW lipopolysaccharide (LPS). Clinical and physiological responses were measured from 0 to 72 h relative to LPS injection. Data were analyzed with mixed models that included fixed effects of treatment and time, and random effect of block. Orthogonal contrasts evaluated the effects of (1) source (CAL vs. CHOL), (2) dose (1.5 vs. 3.0 µg/kg BW), (3) interaction between source and dose, and (4) supplementation (CON vs. all other treatments) of vitamin D. From 21 to 91 d of the experiment, mean BW of supplemented calves was less compared with CON calves, but the effect was predominantly a result of the CHOL calves, which tended to weigh less than the CAL calves. Supplementing vitamin D increased concentrations of 25-hydroxyvitamin D in serum compared with CON, but the increment from increasing the dose from 1.5 to 3.0 µg/kg BW was greater for CAL compared with CHOL (CON = 18.9, CHOL = 24.7 and 29.6, CAL = 35.6 and 65.7 ± 3.2 ng/mL, respectively). Feeding CAL also increased serum Ca and P compared with CHOL. An interaction between source and dose of treatment was observed for rectal temperature and derivatives of reactive metabolites after LPS challenge because calves receiving CHOL3 and CAL1.5 had lower rectal temperatures and plasma derivatives of reactive metabolites compared with calves receiving CHOL1.5 and CAL3. Supplementing vitamin D increased plasma P concentrations post-LPS challenge compared with CON, but plasma concentrations of Ca, Mg, fatty acids, glucose, ß-hydroxybutyrate, haptoglobin, tumor necrosis factor-α, and antioxidant potential did not differ among treatments post-LPS challenge. Last, supplementing vitamin D increased granulocytes as a percentage of blood leukocytes post-LPS challenge compared with CON. Supplementing CAL as a source of vitamin D to dairy calves was more effective at increasing serum 25-hydroxyvitamin D, Ca, and P concentrations compared with feeding CHOL. Supplemental source and dose of vitamin D also influenced responses to the LPS challenge.


Asunto(s)
Endotoxinas , Lipopolisacáridos , Animales , Bovinos , Masculino , Alimentación Animal/análisis , Peso Corporal , Colecalciferol , Dieta/veterinaria , Suplementos Dietéticos , Leche , Vitaminas , Destete
15.
J Dairy Sci ; 106(2): 954-973, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36543649

RESUMEN

The objectives of the experiment were to determine the effects of supplementing 2 amounts of 25-hydroxyvitamin D3 (calcidiol; CAL) compared with equal amounts of vitamin D3 (cholecalciferol; CHOL) on serum concentrations, absorptions, and retentions of Ca, Mg, and P in periparturient dairy cows. One hundred seventy-seven (133 parous and 44 nulliparous) pregnant Holstein cows were enrolled in the experiment. Cows were blocked by parity and previous lactation milk yield (parous) or genetic merit for energy-corrected milk yield (nulliparous) and assigned randomly to receive 1 or 3 mg/d of CAL or CHOL in a 2 × 2 factorial arrangement of treatments. Treatments were provided to individual cows as a top-dress to the prepartum diet from 250 d gestation until parturition. The prepartum diet had a dietary cation-anion difference of -128 mEq/kg of dry matter. All cows were fed a common postpartum diet containing 46 µg of vitamin D3/kg of dry matter without further supplementation of treatments. Concentrations of vitamin D metabolites, Ca, Mg, and P in serum were measured pre- and postpartum, in addition to total-tract digestibility and urinary excretion of Ca, Mg, and P in the prepartum period. Feeding 3 mg compared with 1 mg of CAL increased serum 25-hydroxyvitamin D3 (CAL1 = 94 vs. CAL3 = 173 ± 3 ng/mL). In comparison, the increment in serum 25-hydroxyvitamin D3 from feeding 3 mg compared with 1 mg of CHOL was small (CHOL1 = 58 vs. CHOL3 = 64 ± 3 ng/mL). Feeding CAL increased prepartum concentration of P in serum compared with CHOL (CHOL = 1.87 vs. CAL = 2.01 ± 0.02 mM), regardless of the amount fed, but neither source nor amount affected prepartum Ca or Mg in serum. Feeding CAL increased serum Ca and P for the first 11 d postpartum compared with CHOL (CHOL = 2.12 vs. CAL = 2.16 ± 0.01 mM serum Ca; CHOL = 1.70 vs. CAL = 1.78 ± 0.02 mM serum P) but the amount of vitamin D did not affect postpartum concentrations of Ca, Mg, and P in serum. Feeding CAL increased prepartum apparent digestibility of Ca compared with CHOL (CHOL = 26.6 vs. CAL = 33.5 ± 2.8%) but treatments did not affect Ca retention prepartum. Neither source nor amount of vitamin D affected Mg and P apparent digestibility, but CAL decreased the concentration of P excreted in urine during the prepartum period (CHOL = 1.8 vs. CAL = 0.8 ± 0.3 g/d). Calcidiol tended to increase the amount of Ca secreted in colostrum (CHOL = 9.1 vs. CAL = 11.2 ± 0.9 g/d) and Ca excreted in urine postpartum (CHOL = 0.4 vs. CAL = 0.6 ± 0.1 g/d) compared with CHOL. Collectively, feeding CAL at 1 or 3 mg/d compared with CHOL in the last 24 d of gestation is an effective way to increase periparturient serum P concentration and postpartum serum Ca of dairy cows fed a prepartum diet with negative DCAD.


Asunto(s)
Calcio , Vitamina D , Embarazo , Femenino , Bovinos , Animales , Vitamina D/metabolismo , Magnesio , Calcifediol/metabolismo , Suplementos Dietéticos , Fósforo , Dieta/veterinaria , Colecalciferol/metabolismo , Calcio de la Dieta , Vitaminas , Lactancia , Leche/metabolismo , Periodo Posparto
16.
J Dairy Sci ; 106(2): 974-989, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36526464

RESUMEN

The objectives of this experiment were to determine the effects of supplementing 25-hydroxyvitamin D3 (calcidiol, CAL) compared with vitamin D3 (cholecalciferol, CHOL) at 1 or 3 mg/d in late gestation on production outcomes of dairy cows. One hundred thirty-three parous and 44 nulliparous pregnant Holstein cows were enrolled in the experiment. Cows were blocked by parity and previous lactation milk yield (parous) or genetic merit (nulliparous) and assigned randomly to receive 1 or 3 mg/d of CAL or CHOL in a 2 × 2 factorial arrangement of treatments (CAL1, CAL3, CHOL1, and CHOL3). Treatments were provided to individual cows as a top-dress to the prepartum diet from 250 d in gestation until parturition. The prepartum diet had a dietary cation-anion difference of -128 mEq/kg of dry matter. Production and disease were evaluated for the first 42 d in milk, and reproduction was evaluated to 300 d in milk. Incidence of postpartum diseases did not differ among treatments. Feeding CAL compared with CHOL increased yields of colostrum and colostrum fat, protein, and total solids, resulting in an increased amount of net energy for lactation secreted as colostrum (CHOL = 7.0 vs. CAL = 9.0 ± 0.7 Mcal). An interaction between source and amount was observed for milk yield: CAL3 increased milk yield compared with CHOL3 (CHOL3 = 34.1 vs. CAL3 = 38.7 ± 1.4 kg/d) but milk yield did not differ between CAL1 and CHOL1 (CHOL1 = 36.9 vs. CAL1 = 36.4 ± 1.4 kg/d). Concentrations of serum calcidiol on day of calving and average serum Ca from d 2 to 11 postpartum were positively associated with milk yield in the first 42 d in milk. Interactions between source and amount of vitamin D were also observed for pregnancy after first AI: the percentage of cows receiving CHOL1 and CAL3 that became pregnant was smaller than that of cows receiving CHOL3 and CAL1. However, pregnancy per AI and pregnancy by 300 d in milk did not differ among treatments. Overall, CAL3 increased milk yield compared with CHOL3, whereas in cows fed 1 mg/d (CAL1 and CHOL1), the source of vitamin D generally had no effect. The effect of CAL3 may be explained in part by serum CAL concentrations and postpartum serum Ca, which were associated with milk yield.


Asunto(s)
Calcifediol , Suplementos Dietéticos , Femenino , Embarazo , Bovinos , Animales , Calcifediol/metabolismo , Dieta/veterinaria , Vitamina D/farmacología , Vitamina D/metabolismo , Periodo Posparto , Lactancia , Colecalciferol/metabolismo , Leche/metabolismo , Paridad , Vitaminas/metabolismo
17.
J Dairy Sci ; 106(6): 4198-4213, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37080784

RESUMEN

Objectives of this experiment were to study the effect of infusing utero-pathogenic bacteria to induce endometrial inflammation on productive performance in early lactation and subsequent reproduction. Although endometritis is associated with perturbed reproduction, numerous factors may contribute to the observed association. It was hypothesized that induced endometrial inflammation, resulting in localized and systemic inflammatory responses, compromises production and reproduction. Holstein cows without clinical disease and with less than 18% polymorphonuclear leukocytes (PMN) in endometrial cytology on d 31 ± 3 postpartum had their estrous cycle synchronized. Cows were blocked by parity and genomic breeding value for cow conception rate and, within block, assigned randomly to remain as untreated controls (CON; n = 37) or to receive an intrauterine infusion of 5.19 × 108 cfu Escherichia coli and 4.34 × 108 cfu Trueperella pyogenes during the luteal phase to induce endometrial inflammation (INF; n = 48). Endometrial cytology was taken on d 2 and 7 after treatment to evaluate the proportion of PMN. Rectal temperature, dry matter intake, and yields of milk and components were measured in the first 7 d after treatment. Blood serum was analyzed for concentration of haptoglobin. Leukocytes were isolated from blood on d 2 and 7 after treatment and on d 19 after artificial insemination (AI) and mRNA was quantified for a select group of genes. Cows received AI and reproduction was followed for 300 d postpartum. Bacterial infusion induced endometrial inflammation with increased proportions of PMN in the endometrial cytology on d 2 (4.4 ± 0.7 vs. 26.3 ± 2.8%) and 7 (10.9 ± 1.7 vs. 17.4 ± 2.1%) after treatment, resulting in increased mean prevalence of subclinical endometritis (>10% PMN; 23.3 ± 6.3 vs. 80.9 ± 5.1%). Rectal temperature did not differ between CON and INF, but the concentration of haptoglobin in serum tended to increase in INF compared with CON (113 ± 14 vs. 150 ± 16 µg/mL). Induced endometrial inflammation reduced yields of milk (44.9 ± 0.8 vs. 41.6 ± 0.8 kg/d), protein (1.19 ± 0.03 vs. 1.12 ± 0.03 kg/d), and lactose (2.17 ± 0.04 vs. 2.03 ± 0.04 kg/d) and tended to reduce dry matter intake (20.7 ± 0.5 vs. 19.4 ± 0.6 kg/d) in the first 7 d after treatment. Indeed, the reduction in milk yield lasted 4 wk. However, treatment did not affect yields of energy-corrected milk or fat because treatment with INF increased the concentration of fat in milk (3.54 ± 0.10 vs. 3.84 ± 0.10%). Induced endometrial inflammation reduced pregnancy per AI at all inseminations (33.4 ± 5.1 vs. 21.6 ± 3.7%) and the hazard of pregnancy (0.61; 95% CI = 0.36-1.04), which extended the median days open by 24 d. Blood leukocytes from INF cows had increased mRNA expression of the pro-inflammatory gene IL1B on d 2 and 7 after treatment, but reduced expression of the IFN-stimulated genes ISG15 and MX2 on d 19 after AI. Induced endometrial inflammation depressed production and caused long-term negative effects on reproduction in lactating dairy cows.


Asunto(s)
Endometritis , Lactancia , Embarazo , Femenino , Bovinos , Animales , Endometritis/tratamiento farmacológico , Endometritis/veterinaria , Haptoglobinas/metabolismo , Reproducción/fisiología , Periodo Posparto , Leche/metabolismo , Inflamación/metabolismo , Inflamación/veterinaria
18.
J Dairy Sci ; 106(11): 8098-8109, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37641346

RESUMEN

The objective of this study was to identify metabolites associated with metritis and use them for identification of cellular mechanisms affected during transition into lactation. Holstein cows (n = 104) had blood collected in the prepartum period (d -14 ± 6 relative to calving), at calving (d 0), and at the day of metritis diagnosis (d 7 ± 2 after calving). Cows with reddish or brownish, watery, and fetid discharge were diagnosed with metritis (n = 52). Cows with metritis were paired with herdmates without metritis (n = 52) based on days in milk. The metabolome of plasma samples was evaluated using untargeted gas chromatography time-of-flight mass spectrometry. Univariate analyses included t-tests and fold change analyses. Metabolites with false discovery rate adjusted P ≤ 0.10 on t-tests were used for partial least squares discriminant analysis coupled with permutational analysis using 2,000 permutations. Metabolites with false discovery rate adjusted P ≤ 0.10 on t-tests were also used for enriched pathway analyses and identification of cellular processes. Cows that developed metritis had affected cellular processes associated with lower amino acid metabolism in the prepartum period, greater lipolysis, cell death, and oxidative stress at calving and at metritis diagnosis, and greater leukocyte activation at calving, but lower immune cell activation at metritis diagnosis. In summary, cows that developed metritis had plasma metabolomic changes associated with greater lipolysis, oxidative stress, and a dysregulated immune response which may predispose cows to metritis development.

19.
J Dairy Sci ; 106(12): 9244-9259, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37641354

RESUMEN

The objective was to unravel the peripartum immune and metabolic changes associated with metritis in Holstein cows. Holstein cows (n = 128) had blood collected at -14, 0, 3, and 7 d relative to parturition (DRP). Flow cytometry was used to evaluate blood leukocyte counts, proportions, and activation. Total cells, live cells, single cells, monocytes (CD172α+/CD14+), polymorphonuclears (CD172α+/CD14-/SSChigh), B-cells (CD21+/MHCII+), CD4+ T-cells (CD4+), CD8+ T-cells (CD8+), and γδ T-cells (γδTCR+) were evaluated. Both CD62L and CD11b were used as markers of cell activation. Major histocompatibility complex class II was used as a marker of antigen presentation in monocytes. A Milliplex Bovine Cytokine/Chemokine 08-plex kit was used to evaluate plasma concentrations of IFN-γ, IL-1α, IL-1ß, IL-4, IL-6, IL-8, IL-10, and tumor necrosis factor-α. The body weight (BW) change prepartum was calculated as the difference between calving BW and prepartum BW divided by the number of days between measurements. Plasma fatty acids (FA) were measured at -14 and 0 DRP using untargeted gas chromatography with time-of-flight mass spectrometry. Data were analyzed by ANOVA for repeated measures. Cows that developed metritis (n = 57) had greater prepartum BW, prepartum BW loss, and greater FA concentrations at calving. Plasma FA at calving was positively correlated with IL-1ß. Cows that developed metritis had persistent systemic inflammation, which was demonstrated by greater B-cell activation, greater pro-inflammatory cytokine concentrations, and greater cell damage pre- and postpartum. Postpartum, we observed greater polymorphonuclear cell activation and extravasation but lesser monocytes and CD4+ T-cells activation and extravasation, which suggests postpartum immune tolerance. Greater prepartum adiposity in cows that developed metritis may lead to systemic inflammation pre- and postpartum and immune tolerance postpartum, which may lead to failure to prevent bacterial infection, and development of puerperal metritis.


Asunto(s)
Enfermedades de los Bovinos , Enfermedad Inflamatoria Pélvica , Femenino , Bovinos , Animales , Linfocitos T CD8-positivos , Cromatografía de Gases y Espectrometría de Masas/veterinaria , Periodo Posparto , Citocinas , Inflamación/veterinaria , Enfermedad Inflamatoria Pélvica/veterinaria , Lactancia
20.
Int J Mol Sci ; 24(2)2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36674867

RESUMEN

Untargeted multi-omics analysis of plasma is an emerging tool for the identification of novel biomarkers for evaluating disease prognosis, and for developing a better understanding of molecular mechanisms underlying human disease. The successful application of metabolomic and proteomic approaches relies on reproducibly quantifying a wide range of metabolites and proteins. Herein, we report the results of untargeted metabolomic and proteomic analyses from blood plasma samples following analyte extraction by two frequently-used solvent systems: chloroform/methanol and methanol-only. Whole blood samples were collected from participants (n = 6) at University Hospital Sharjah (UHS) hospital, then plasma was separated and extracted by two methods: (i) methanol precipitation and (ii) 4:3 methanol:chloroform extraction. The coverage and reproducibility of the two methods were assessed by ultra-high-performance liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (UHPLC-ESI-QTOF-MS). The study revealed that metabolite extraction by methanol-only showed greater reproducibility for both metabolomic and proteomic quantifications than did methanol/chloroform, while yielding similar peptide coverage. However, coverage of extracted metabolites was higher with the methanol/chloroform precipitation.


Asunto(s)
Metanol , Espectrometría de Masas en Tándem , Humanos , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Metanol/química , Cloroformo , Reproducibilidad de los Resultados , Proteómica
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