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1.
Nature ; 618(7964): 349-357, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37258678

RESUMEN

The incidence of Alzheimer's disease (AD), the leading cause of dementia, increases rapidly with age, but why age constitutes the main risk factor is still poorly understood. Brain ageing affects oligodendrocytes and the structural integrity of myelin sheaths1, the latter of which is associated with secondary neuroinflammation2,3. As oligodendrocytes support axonal energy metabolism and neuronal health4-7, we hypothesized that loss of myelin integrity could be an upstream risk factor for neuronal amyloid-ß (Aß) deposition, the central neuropathological hallmark of AD. Here we identify genetic pathways of myelin dysfunction and demyelinating injuries as potent drivers of amyloid deposition in mouse models of AD. Mechanistically, myelin dysfunction causes the accumulation of the Aß-producing machinery within axonal swellings and increases the cleavage of cortical amyloid precursor protein. Suprisingly, AD mice with dysfunctional myelin lack plaque-corralling microglia despite an overall increase in their numbers. Bulk and single-cell transcriptomics of AD mouse models with myelin defects show that there is a concomitant induction of highly similar but distinct disease-associated microglia signatures specific to myelin damage and amyloid plaques, respectively. Despite successful induction, amyloid disease-associated microglia (DAM) that usually clear amyloid plaques are apparently distracted to nearby myelin damage. Our data suggest a working model whereby age-dependent structural defects of myelin promote Aß plaque formation directly and indirectly and are therefore an upstream AD risk factor. Improving oligodendrocyte health and myelin integrity could be a promising target to delay development and slow progression of AD.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Vaina de Mielina , Placa Amiloide , Animales , Ratones , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Modelos Animales de Enfermedad , Vaina de Mielina/metabolismo , Vaina de Mielina/patología , Placa Amiloide/genética , Placa Amiloide/metabolismo , Placa Amiloide/patología , Axones/metabolismo , Axones/patología , Microglía/metabolismo , Microglía/patología , Análisis de Expresión Génica de una Sola Célula , Factores de Riesgo , Progresión de la Enfermedad
2.
EMBO J ; 43(8): 1499-1518, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38528181

RESUMEN

The intestinal pathogen Salmonella enterica rapidly enters the bloodstream after the invasion of intestinal epithelial cells, but how Salmonella breaks through the gut-vascular barrier is largely unknown. Here, we report that Salmonella enters the bloodstream through intestinal CX3CR1+ macrophages during early infection. Mechanistically, Salmonella induces the migration/invasion properties of macrophages in a manner dependent on host cell actin and on the pathogen effector SteC. SteC recruits host myosin light chain protein Myl12a and phosphorylates its Ser19 and Thr20 residues. Myl12a phosphorylation results in actin rearrangement, and enhanced migration and invasion of macrophages. SteC is able to utilize a wide range of NTPs other than ATP to phosphorylate Myl12a. We further solved the crystal structure of SteC, which suggests an atypical dimerization-mediated catalytic mechanism. Finally, in vivo data show that SteC-mediated cytoskeleton manipulation is crucial for Salmonella breaching the gut vascular barrier and spreading to target organs.


Asunto(s)
Cadenas Ligeras de Miosina , Salmonella enterica , Cadenas Ligeras de Miosina/genética , Cadenas Ligeras de Miosina/metabolismo , Actinas/metabolismo , Células Epiteliales/metabolismo , Macrófagos/metabolismo
3.
Nature ; 605(7908): 152-159, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35477759

RESUMEN

Atherosclerotic plaques develop in the inner intimal layer of arteries and can cause heart attacks and strokes1. As plaques lack innervation, the effects of neuronal control on atherosclerosis remain unclear. However, the immune system responds to plaques by forming leukocyte infiltrates in the outer connective tissue coat of arteries (the adventitia)2-6. Here, because the peripheral nervous system uses the adventitia as its principal conduit to reach distant targets7-9, we postulated that the peripheral nervous system may directly interact with diseased arteries. Unexpectedly, widespread neuroimmune cardiovascular interfaces (NICIs) arose in mouse and human atherosclerosis-diseased adventitia segments showed expanded axon networks, including growth cones at axon endings near immune cells and media smooth muscle cells. Mouse NICIs established a structural artery-brain circuit (ABC): abdominal adventitia nociceptive afferents10-14 entered the central nervous system through spinal cord T6-T13 dorsal root ganglia and were traced to higher brain regions, including the parabrachial and central amygdala neurons; and sympathetic efferent neurons projected from medullary and hypothalamic neurons to the adventitia through spinal intermediolateral neurons and both coeliac and sympathetic chain ganglia. Moreover, ABC peripheral nervous system components were activated: splenic sympathetic and coeliac vagus nerve activities increased in parallel to disease progression, whereas coeliac ganglionectomy led to the disintegration of adventitial NICIs, reduced disease progression and enhanced plaque stability. Thus, the peripheral nervous system uses NICIs to assemble a structural ABC, and therapeutic intervention in the ABC attenuates atherosclerosis.


Asunto(s)
Aterosclerosis , Placa Aterosclerótica , Animales , Aterosclerosis/prevención & control , Progresión de la Enfermedad , Ganglios Espinales , Ganglios Simpáticos , Ratones , Neuronas/fisiología , Placa Aterosclerótica/prevención & control
4.
N Engl J Med ; 390(23): 2178-2190, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38899695

RESUMEN

BACKGROUND: Immune thrombocytopenia (ITP) is an autoimmune disease characterized by autoantibody-mediated platelet destruction. Treatment with CM313, a novel anti-CD38 monoclonal antibody, can result in targeted clearance of CD38-positive cells, including plasma cells. METHODS: We conducted a phase 1-2, open-label study to evaluate the safety and efficacy of CM313 in adult patients with ITP. CM313 was administered intravenously at a dose of 16 mg per kilogram of body weight every week for 8 weeks, followed by a 16-week follow-up period. The primary outcomes were adverse events and documentation of two or more consecutive platelet counts of at least 50×109 per liter within 8 weeks after the first dose of CM313. The status of peripheral-blood immune cells in patients and changes in the mononuclear phagocytic system in passive mouse models of ITP receiving anti-CD38 therapy were monitored. RESULTS: Of the 22 patients included in the study, 21 (95%) had two consecutive platelet counts of at least 50×109 per liter during the treatment period, with a median cumulative response duration of 23 weeks (interquartile range, 17 to 24). The median time to the first platelet count of at least 50×109 per liter was 1 week (range, 1 to 3). The most common adverse events that occurred during the study were infusion-related reaction (in 32% of the patients) and upper respiratory tract infection (in 32%). After CD38-targeted therapy, the percentage of CD56dimCD16+ natural killer cells, the expression of CD32b on monocytes in peripheral blood, and the number of macrophages in the spleen of the passive mouse models of ITP all decreased. CONCLUSIONS: In this study, anti-CD38 targeted therapy rapidly boosted platelet levels by inhibiting antibody-dependent cell-mediated cytotoxicity on platelets, maintained long-term efficacy by clearing plasma cells, and was associated with mainly low-grade toxic effects. (Funded by the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences and others; ClinicalTrials.gov number, NCT05694767).


Asunto(s)
Anticuerpos Monoclonales , Púrpura Trombocitopénica Idiopática , Adulto , Anciano , Animales , Femenino , Humanos , Masculino , Ratones , Persona de Mediana Edad , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales/efectos adversos , Recuento de Plaquetas , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Púrpura Trombocitopénica Idiopática/inmunología
5.
Plant Cell ; 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38801738

RESUMEN

Virus-induced drought tolerance presents a fascinating facet of biotic-abiotic interaction in plants, yet its molecular intricacies remain unclear. Our study shows that cowpea mild mottle virus (CPMMV) infection enhances drought tolerance in common bean (Phaseolus vulgaris) plants through a virus-derived small interfering RNA (vsiRNA)-activated autophagy pathway. Specifically, a 21-bp vsiRNA originating from the CPMMV Triple Gene Block1 (TGB1) gene targeted the 5' untranslated region (UTR) of the host Teosinte branched 1, Cycloidea, Proliferating Cell Factor (TCP) transcription factor gene PvTCP2, independent of the known role of TGB1 as an RNA silencing suppressor. This targeting attenuated the expression of PvTCP2, which encodes a transcriptional repressor, and in turn upregulated the core autophagy-related gene (ATG) PvATG8c, leading to activated autophagy activity surpassing the level induced by drought or CPMMV infection alone. The downstream EARLY RESPONSIVE TO DEHYDRATION (ERD) effector PvERD15 is a homologue of Arabidopsis thaliana AtERD15, which positively regulates stomatal aperture. PvERD15 was degraded in PvATG8c-mediated autophagy. Therefore, we establish a TGB1-PvTCP2-PvATG8c-PvERD15 module as a trans-kingdom fine-tuning mechanism that contributes to virus-induced drought tolerance in plant-drought-virus interactions.

6.
Proc Natl Acad Sci U S A ; 121(2): e2310763120, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38165928

RESUMEN

Habitat degradation and loss of genetic diversity are common threats faced by almost all of today's wild cats. Big cats, such as tigers and lions, are of great concern and have received considerable conservation attention through policies and international actions. However, knowledge of and conservation actions for small wild cats are lagging considerably behind. The black-footed cat, Felis nigripes, one of the smallest felid species, is experiencing increasing threats with a rapid reduction in population size. However, there is a lack of genetic information to assist in developing effective conservation actions. A de novo assembly of a high-quality chromosome-level reference genome of the black-footed cat was made, and comparative genomics and population genomics analyses were carried out. These analyses revealed that the most significant genetic changes in the evolution of the black-footed cat are the rapid evolution of sensory and metabolic-related genes, reflecting genetic adaptations to its characteristic nocturnal hunting and a high metabolic rate. Genomes of the black-footed cat exhibit a high level of inbreeding, especially for signals of recent inbreeding events, which suggest that they may have experienced severe genetic isolation caused by habitat fragmentation. More importantly, inbreeding associated with two deleterious mutated genes may exacerbate the risk of amyloidosis, the dominant disease that causes mortality of about 70% of captive individuals. Our research provides comprehensive documentation of the evolutionary history of the black-footed cat and suggests that there is an urgent need to investigate genomic variations of small felids worldwide to support effective conservation actions.


Asunto(s)
Felidae , Felis , Leones , Humanos , Animales , Felidae/genética , Genoma , Genómica
7.
Proc Natl Acad Sci U S A ; 120(7): e2216099120, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36757888

RESUMEN

Crystal nucleation is relevant across the domains of fundamental and applied sciences. However, in many cases, its mechanism remains unclear due to a lack of temporal or spatial resolution. To gain insights into the molecular details of nucleation, some form of molecular dynamics simulations is typically performed; these simulations, in turn, are limited by their ability to run long enough to sample the nucleation event thoroughly. To overcome the timescale limits in typical molecular dynamics simulations in a manner free of prior human bias, here, we employ the machine learning-augmented molecular dynamics framework "reweighted autoencoded variational Bayes for enhanced sampling (RAVE)." We study two molecular systems-urea and glycine-in explicit all-atom water, due to their enrichment in polymorphic structures and common utility in commercial applications. From our simulations, we observe multiple back-and-forth nucleation events of different polymorphs from homogeneous solution; from these trajectories, we calculate the relative ranking of finite-sized polymorph crystals embedded in solution, in terms of the free-energy difference between the finite-sized crystal polymorph and the original solution state. We further observe that the obtained reaction coordinates and transitions are highly nonclassical.

8.
Proc Natl Acad Sci U S A ; 120(16): e2301879120, 2023 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-37036969

RESUMEN

Light plays an important role in determining plant architecture, which greatly influences crop yield. However, the precise mechanisms by which light signaling regulates bud outgrowth remain to be identified. Here, we show that light regulates bud outgrowth via both HY5 and brassinosteroid (BR)-dependent pathways in tomato. Inactivation of the red-light photoreceptor PHYB, or deficiencies in PHYB or the blue-light photoreceptor CRY1a, inhibits bud outgrowth and leads to decreased accumulation of HY5 protein and increased transcript level of BRANCHED1 (BRC1), a central integrator of branching signals. HY5, functioning as a mobile systemic signal from leaves, promotes bud outgrowth by directly suppressing BRC1 transcript and activating the transcript of BR biosynthesis genes within the lateral buds in tomato. Furthermore, BRC1 prevents the accumulation of cytokinin (CK) and gibberellin (GA) by directly inhibiting the transcript of CK synthesis gene LOG4, while increasing the transcript levels of CK and GA degradation genes (CKX7, GA2ox4, and GA2ox5), leading to an arrest of bud outgrowth. Moreover, bud outgrowth occurs predominantly in the day due to the suppression of BRC1 transcript by HY5. These findings demonstrate that light-inducible HY5 acts as a systemic signaling factor in fine-tuning the bud outgrowth of tomato.


Asunto(s)
Solanum lycopersicum , Solanum lycopersicum/genética , Brotes de la Planta , Factores de Transcripción/metabolismo , Citocininas/metabolismo , Hormonas/metabolismo , Regulación de la Expresión Génica de las Plantas
9.
Plant J ; 117(5): 1503-1516, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38059690

RESUMEN

Plant diseases, which seriously damage crop production, are in most cases caused by fungal pathogens. In this study, we found that the Raf-like MAPKKKs STY8 (SERINE/THREONINE/TYROSINE KINASE 8), STY17, and STY46 negatively regulate resistance to the fungal pathogen Botrytis cinerea through jasmonate response in Arabidopsis. Moreover, STY8/STY17/STY46 homologs negatively contribute to chitin signaling. We further identified MKK7 as the MAPKK component interacting with STY8/STY17/STY46 homologs. MKK7 positively contributes to resistance to B. cinerea and chitin signaling. Furthermore, we found that STY8/STY17/STY46 homologs negatively affect the accumulation of MKK7, in accordance with the opposite roles of MKK7 and STY8/STY17/STY46 homologs in defense against B. cinerea. These results provide new insights into the mechanisms precisely regulating plant immunity via Raf-like MAPKKKs.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Quinasas Quinasa Quinasa PAM/metabolismo , Botrytis/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Quitina/metabolismo , Enfermedades de las Plantas/microbiología , Regulación de la Expresión Génica de las Plantas , Resistencia a la Enfermedad/genética
10.
Plant Physiol ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38850036

RESUMEN

Water transportation to developing tissues relies on the structure and function of plant xylem cells. Plant microtubules govern the direction of cellulose microfibrils and guide secondary cell wall formation and morphogenesis. However, the relevance of microtubule-determined xylem wall thickening patterns in plant hydraulic conductivity remains unclear. In the present study, we identified a maize (Zea mays) semi-dominant mutant, designated drought-overly-sensitive1 (ZmDos1), the upper leaves of which wilted even when exposed to well-watered conditions during growth; the wilting phenotype was aggravated by increased temperatures and decreased humidity. Protoxylem vessels in the stem and leaves of the mutant showed altered thickening patterns of the secondary cell wall (from annular to spiral), decreased inner diameters, and limited water transport efficiency. The causal mutation for this phenotype was found to be a G-to-A mutation in the maize gene α-tubulin4, resulting in a single amino acid substitution at position 196 (E196K). Ectopic expression of the mutant α-tubulin4 in Arabidopsis (Arabidopsis thaliana) changed the orientation of microtubule arrays, suggesting a determinant role of this gene in microtubule assembly and secondary cell wall thickening. Our findings suggest that the spiral wall thickenings triggered by the α-tubulin mutation are stretched during organ elongation, causing a smaller inner diameter of the protoxylem vessels and affecting water transport in maize. This study underscores the importance of tubulin-mediated protoxylem wall thickening in regulating plant hydraulics, improves our understanding of the relationships between protoxylem structural features and functions, and offers candidate genes for the genetic enhancement of maize.

11.
Plant Cell ; 34(5): 1890-1911, 2022 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-35166333

RESUMEN

The unique morphology of grass stomata enables rapid responses to environmental changes. Deciphering the basis for these responses is critical for improving food security. We have developed a planta platform of single-nucleus RNA-sequencing by combined fluorescence-activated nuclei flow sorting, and used it to identify cell types in mature and developing stomata from 33,098 nuclei of the maize epidermis-enriched tissues. Guard cells (GCs) and subsidiary cells (SCs) displayed differential expression of genes, besides those encoding transporters, involved in the abscisic acid, CO2, Ca2+, starch metabolism, and blue light signaling pathways, implicating coordinated signal integration in speedy stomatal responses, and of genes affecting cell wall plasticity, implying a more sophisticated relationship between GCs and SCs in stomatal development and dumbbell-shaped guard cell formation. The trajectory of stomatal development identified in young tissues, and by comparison to the bulk RNA-seq data of the MUTE defective mutant in stomatal development, confirmed known features, and shed light on key participants in stomatal development. Our study provides a valuable, comprehensive, and fundamental foundation for further insights into grass stomatal function.


Asunto(s)
Estomas de Plantas , Zea mays , Humanos , Hojas de la Planta/metabolismo , Estomas de Plantas/metabolismo , Poaceae/genética , Transcriptoma/genética , Zea mays/genética
12.
Glia ; 72(8): 1374-1391, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38587131

RESUMEN

Oligodendrocytes and astrocytes are metabolically coupled to neuronal compartments. Pyruvate and lactate can shuttle between glial cells and axons via monocarboxylate transporters. However, lactate can only be synthesized or used in metabolic reactions with the help of lactate dehydrogenase (LDH), a tetramer of LDHA and LDHB subunits in varying compositions. Here we show that mice with a cell type-specific disruption of both Ldha and Ldhb genes in oligodendrocytes lack a pathological phenotype that would be indicative of oligodendroglial dysfunctions or lack of axonal metabolic support. Indeed, when combining immunohistochemical, electron microscopical, and in situ hybridization analyses in adult mice, we found that the vast majority of mature oligodendrocytes lack detectable expression of LDH. Even in neurodegenerative disease models and in mice under metabolic stress LDH was not increased. In contrast, at early development and in the remyelinating brain, LDHA was readily detectable in immature oligodendrocytes. Interestingly, by immunoelectron microscopy LDHA was particularly enriched at gap junctions formed between adjacent astrocytes and at junctions between astrocytes and oligodendrocytes. Our data suggest that oligodendrocytes metabolize lactate during development and remyelination. In contrast, for metabolic support of axons mature oligodendrocytes may export their own glycolysis products as pyruvate rather than lactate. Lacking LDH, these oligodendrocytes can also "funnel" lactate through their "myelinic" channels between gap junction-coupled astrocytes and axons without metabolizing it. We suggest a working model, in which the unequal cellular distribution of LDH in white matter tracts facilitates a rapid and efficient transport of glycolysis products among glial and axonal compartments.


Asunto(s)
Axones , Glucólisis , L-Lactato Deshidrogenasa , Oligodendroglía , Animales , Oligodendroglía/metabolismo , Axones/metabolismo , L-Lactato Deshidrogenasa/metabolismo , L-Lactato Deshidrogenasa/genética , Glucólisis/fisiología , Ratones , Regulación hacia Abajo/fisiología , Ratones Endogámicos C57BL , Lactato Deshidrogenasa 5/metabolismo , Astrocitos/metabolismo , Astrocitos/ultraestructura , Ratones Transgénicos , Isoenzimas/metabolismo , Isoenzimas/genética , Uniones Comunicantes/metabolismo , Uniones Comunicantes/ultraestructura , Ratones Noqueados
13.
Br J Haematol ; 204(6): 2418-2428, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38513635

RESUMEN

This study aimed to identify key proteomic analytes correlated with response to splenectomy in primary immune thrombocytopenia (ITP). Thirty-four patients were retrospectively collected in the training cohort and 26 were prospectively enrolled as validation cohort. Bone marrow biopsy samples of all participants were collected prior to the splenectomy. A total of 12 modules of proteins were identified by weighted gene co-expression network analysis (WGCNA) method in the developed cohort. The tan module positively correlated with megakaryocyte counts before splenectomy (r = 0.38, p = 0.027), and time to peak platelet level after splenectomy (r = 0.47, p = 0.005). The blue module significantly correlated with response to splenectomy (r = 0.37, p = 0.0031). KEGG pathways analysis found that the PI3K-Akt signalling pathway was predominantly enriched in the tan module, while ribosomal and spliceosome pathways were enriched in the blue module. Machine learning algorithm identified the optimal combination of biomarkers from the blue module in the training cohort, and importantly, cofilin-1 (CFL1) was independently confirmed in the validation cohort. The C-index of CFL1 was >0.7 in both cohorts. Our results highlight the use of bone marrow proteomics analysis for deriving key analytes that predict the response to splenectomy, warranting further exploration of plasma proteomics in this patient population.


Asunto(s)
Aprendizaje Automático , Proteómica , Púrpura Trombocitopénica Idiopática , Esplenectomía , Humanos , Masculino , Femenino , Proteómica/métodos , Púrpura Trombocitopénica Idiopática/cirugía , Púrpura Trombocitopénica Idiopática/sangre , Púrpura Trombocitopénica Idiopática/genética , Adulto , Persona de Mediana Edad , Biomarcadores/sangre , Anciano , Estudios Retrospectivos
14.
Br J Haematol ; 204(6): 2405-2417, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38438130

RESUMEN

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by antibody-mediated platelet destruction and impaired platelet production. The mechanisms underlying ITP and biomarkers predicting the response of drug treatments are elusive. We performed a metabolomic profiling of bone marrow biopsy samples collected from ITP patients admission in a prospective study of the National Longitudinal Cohort of Hematological Diseases. Machine learning algorithms were conducted to discover novel biomarkers to predict ITP patient treatment responses. From the bone marrow biopsies of 91 ITP patients, we quantified a total of 4494 metabolites, including 1456 metabolites in the positive mode and 3038 metabolites in the negative mode. Metabolic patterns varied significantly between groups of newly diagnosed and chronic ITP, with a total of 876 differential metabolites involved in 181 unique metabolic pathways. Enrichment factors and p-values revealed the top metabolically enriched pathways to be sphingolipid metabolism, the sphingolipid signalling pathway, ubiquinone and other terpenoid-quinone biosynthesis, thiamine metabolism, tryptophan metabolism and cofactors biosynthesis, the phospholipase D signalling pathway and the phosphatidylinositol signalling system. Based on patient responses to five treatment options, we screened several metabolites using the Boruta algorithm and ranked their importance using the random forest algorithm. Lipids and their metabolism, including long-chain fatty acids, oxidized lipids, glycerophospholipids, phosphatidylcholine and phosphatidylethanolamine biosynthesis, helped differentiate drug treatment responses. In conclusion, this study revealed metabolic alterations associated with ITP in bone marrow supernatants and a potential biomarker predicting the response to ITP.


Asunto(s)
Aprendizaje Automático , Metabolómica , Púrpura Trombocitopénica Idiopática , Humanos , Púrpura Trombocitopénica Idiopática/metabolismo , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Púrpura Trombocitopénica Idiopática/sangre , Estudios Prospectivos , Masculino , Femenino , Persona de Mediana Edad , Metabolómica/métodos , Adulto , Anciano , Biomarcadores , Metaboloma , Redes y Vías Metabólicas , Resultado del Tratamiento , Médula Ósea/metabolismo , Médula Ósea/patología
15.
Small ; 20(28): e2310519, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38415911

RESUMEN

Rechargeable aqueous ammonium ion (NH4 +) batteries have attracted much attention due to the unique properties of NH4 +. Polyaniline (PA) with outstanding conductivity is a potential cathode material, but it can be oxidized to pernigraniline (PG) rapidly, resulting in its poor stability. In this study, polyaniline@poly(o-fluoroaniline)@carbon layer (PA@POFA@C) is prepared for excellent and durable NH4 + storage. PA@POFA@C exhibits a high capacity of 208 mAh g-1 at 0.2 A g-1 and maintains 126 mAh g-1 at 10 A g-1. More importantly, an excellent capacity retention rate of 88.24% is achieved after 2000 cycles with ≈100% coulombic efficiency. Spectroscopy studies suggest analogous confinement effect can effectively limit the escape of hydrogen in imine group, and form the hydrogen-restricted region between the PA and POFA layer which can provide H+ for the complete reduction of PG. Meanwhile, the hydrophobic effect of POFA effectively restrains the hydrolysis of PG. Interestingly, the introduction of C layer improves the hydrophilicity of electrode and shortens the activation process, serving as the outermost protective layer of the electrode. Finally, PA@POFA@C achieves desirable electrochemical performances with analogous confinement effect. This research provides ideas for the preparation of advanced polymer electrodes for aqueous NH4 + batteries.

16.
J Vasc Surg ; 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38556041

RESUMEN

PURPOSE: The graduate medical education community implemented virtual residency interviews in response to travel restrictions during the COVID-19 pandemic, and this approach has persisted. Although many residency applicants wish to visit in-person prospective training sites, such opportunities could bias programs toward those who are able to meet this financial burden, exacerbating equity concerns. One proposed solution is to offer applicants the opportunity to visit only after a program's rank list is "locked," avoiding favoritism to applicants who visit, but allowing applicants to experience some of the camaraderie, geography, and local effects of an in-person visit. As debate about the optimal format of residency interviews continues, it is important to investigate whether in-person program visits, completed after program rank list certification, provide meaningful benefits to applicants in the residency match process. METHODS: All vascular programs entering the 2023 integrated vascular surgery residency match were invited to participate. Programs agreed to certify their National Resident Matching Program rank lists by February 1, 2023. Applicants then had the opportunity to visit the programs at which they interviewed. The particulars of the visit were determined by the individual programs. Applicants completed their standard rank list and locked on the standard date: March 1, 2023. Applicants then completed a survey regarding the impact of the visits on their rank order list decision-making. Program directors (PDs) completed a survey regarding their experiences as well. Data were collected using REDCap. RESULTS: Twenty-one of the 74 (28%) programs participated. Nineteen PDs completed the postinterview site visit survey (response rate 90%). Applicants interviewing at the participating programs (n = 112) were informed of the study, offered the opportunity to attend postinterview site visits, and received the survey. Forty-seven applicants responded (response rate 42%). Eighty-six percent of applicants stated that the visit impacted their rank list. Most important factors were esprit de corps of the program (86%), the faculty/trainees/staff (81%), and the physical setting (62%). Seventy-one percent of those participating spent ≤$800 on their visit. Eighty-one percent were satisfied with the process. Twenty-one percent of PDs would have changed their rank list if they could have based on the applicants' in-person visit. Sixty-three percent of the visit sessions cost the programs ≤$500, and 63% were satisfied with the process. CONCLUSIONS: This study is the first to document the impact of in-person site visits by applicants on a graduate medical education match process in one specialty. Our results suggest that this process provides meaningful data to applicants that helped them with their decision-making evidenced by most altering their rank lists, while avoiding some of the critical equity issues that accompany traditional in-person interviews. This may provide a model for future interview processes for residency programs.

17.
J Vasc Surg ; 80(1): 260-267.e2, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38493897

RESUMEN

OBJECTIVE: Gender disparities in surgical training and assessment are described in the general surgery literature. Assessment disparities have not been explored in vascular surgery. We sought to investigate gender disparities in operative assessment in a national cohort of vascular surgery integrated residents (VIRs) and fellows (VSFs). METHODS: Operative performance and autonomy ratings from the Society for Improving Medical Professional Learning (SIMPL) application database were collected for all vascular surgery participating institutions from 2018 to 2023. Logistic generalized linear mixed models were conducted to examine the association of faculty and trainee gender on faculty and self-assessment of autonomy and performance. Data were adjusted for post-graduate year and case complexity. Random effects were included to account for clustering effects due to participant, program, and procedure. RESULTS: One hundred three trainees (n = 63 VIRs; n = 40 VSFs; 63.1% men) and 99 faculty (73.7% men) from 17 institutions (n = 12 VIR and n = 13 VSF programs) contributed 4951 total assessments (44.4% by faculty, 55.6% by trainees) across 235 unique procedures. Faculty and trainee gender were not associated with faculty ratings of performance (faculty gender: odds ratio [OR], 0.78; 95% confidence interval [CI], 0.27-2.29; trainee gender: OR, 1.80; 95% CI, 0.76-0.43) or autonomy (faculty gender: OR, 0.99; 95% CI, 0.41-2.39; trainee gender: OR, 1.23; 95% CI, 0.62-2.45) of trainees. All trainees self-assessed at lower performance and autonomy ratings as compared with faculty assessments. However, women trainees rated themselves significantly lower than men for both autonomy (OR, 0.57; 95% CI, 0.43-0.74) and performance (OR, 0.40; 95% CI, 0.30-0.54). CONCLUSIONS: Although gender was not associated with differences in faculty assessment of performance or autonomy among vascular surgery trainees, women trainees perceive themselves as performing with lower competency and less autonomy than their male colleagues. These findings suggest utility for exploring gender differences in real-time feedback delivered to and received by trainees and targeted interventions to align trainee self-perception with actual operative performance and autonomy to optimize surgical skill acquisition.


Asunto(s)
Competencia Clínica , Educación de Postgrado en Medicina , Internado y Residencia , Autonomía Profesional , Cirujanos , Procedimientos Quirúrgicos Vasculares , Humanos , Femenino , Masculino , Procedimientos Quirúrgicos Vasculares/educación , Cirujanos/educación , Cirujanos/psicología , Factores Sexuales , Médicos Mujeres , Estados Unidos , Sexismo , Docentes Médicos , Adulto
18.
Cancer Cell Int ; 24(1): 237, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38971758

RESUMEN

Coiled-coil domain containing 88C (CCDC88C) is a component of non-canonical Wnt signaling, and its dysregulation causes colorectal cancer metastasis. Dysregulated expression of CCDC88C was observed in lymph node metastatic tumor tissues of breast cancer. However, the role of CCDC88C in breast cancer metastasis remains unclear. To address this, the stable BT549 and SKBR3 cell lines with CCDC88C overexpression or knockdown were developed. Loss/gain-of-function experiments suggested that CCDC88C drove breast cancer cell motility in vitro and lung and liver metastasis in vivo. We found that CCDC88C led to c-JUN-induced transcription activation. Overlapping genes were identified from the genes modulated by CCDC88C and c-JUN. CEMIP, one of these overlapping genes, has been confirmed to confer breast cancer metastasis. We found that CCDC88C regulated CEMIP mRNA levels via c-JUN and it exerted pro-metastatic capabilities in a CEMIP-dependent manner. Moreover, we identified the CCDC88C as a substrate of polypeptide N-acetylgalactosaminyltransferase 6 (GALNT6). GALNT6 was positively correlated with CCDC88C protein abundance in the normal breast and breast cancer tissues, indicating that GALNT6 might be associated with expression patterns of CCDC88C in breast cancer. Our data demonstrated that GALNT6 maintained CCDC88C stability by promoting its O-linked glycosylation, and the modification was critical for the pro-metastatic potential of CCDC88C. CCDC88C also could mediate the pro-metastatic potential of GALNT6 in breast cancer. Collectively, our findings uncover that CCDC88C may increase the risk of breast cancer metastasis and elucidate the underlying molecular mechanisms.

19.
Phys Rev Lett ; 132(4): 045001, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38335335

RESUMEN

Laser wakefield acceleration is paving the way for the next generation of electron accelerators, for their own sake and as radiation sources. A controllable dual-wake injection scheme is put forward here to generate an ultrashort triplet electron bunch with high brightness and high polarization, employing a radially polarized laser as a driver. We find that the dual wakes can be driven by both transverse and longitudinal components of the laser field in the quasiblowout regime, sustaining the laser-modulated wakefield which facilitates the subcycle and transversely split injection of the triplet bunch. Polarization of the triplet bunch can be highly preserved due to the laser-assisted collective spin precession and the noncanceled transverse spins. In our three-dimensional particle-in-cell simulations, the triplet electron bunch, with duration about 500 as, six-dimensional brightness exceeding 10^{14} A/m^{2}/0.1% and polarization over 80%, can be generated using a few-terawatt laser. Such an electron bunch could play an essential role in many applications, such as ultrafast imaging, nuclear structure and high-energy physics studies, and the operation of coherent radiation sources.

20.
Chemistry ; 30(10): e202303497, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38017237

RESUMEN

Covalent organic frameworks (COFs) have recently drawn intense attention due to their potential applications in photocatalysis. Herein, we report a multifunctional COF which consists of triphenylamine (TPA) and 2,2'-bipyridine (2, 2'-bipy) entities. The obtained TAPA-BPy-COF is a heterogeneous photocatalyst and can efficiently catalyze the oxidative coupling of thiols to disulfides. In addition, TAPA-BPy-COF can be further metalated by Pd(II) via 2,2'-bipy-metal coordination. The generated Pd@TAPA-BPy-COF can highly promote photocatalytic synthesis of 3-cyanopyridines via cascade addition/cyclization of arylboronic acids with γ-ketodinitriles in heterogeneous way. This work has demonstrated the way for the rational design and preparation of more efficient photoactive COFs for photocatalysis.

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