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1.
Cell ; 186(21): 4632-4651.e23, 2023 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-37776858

RESUMO

The dynamics of immunity to infection in infants remain obscure. Here, we used a multi-omics approach to perform a longitudinal analysis of immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in infants and young children by analyzing blood samples and weekly nasal swabs collected before, during, and after infection with Omicron and non-Omicron variants. Infection stimulated robust antibody titers that, unlike in adults, showed no sign of decay for up to 300 days. Infants mounted a robust mucosal immune response characterized by inflammatory cytokines, interferon (IFN) α, and T helper (Th) 17 and neutrophil markers (interleukin [IL]-17, IL-8, and CXCL1). The immune response in blood was characterized by upregulation of activation markers on innate cells, no inflammatory cytokines, but several chemokines and IFNα. The latter correlated with viral load and expression of interferon-stimulated genes (ISGs) in myeloid cells measured by single-cell multi-omics. Together, these data provide a snapshot of immunity to infection during the initial weeks and months of life.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Criança , Lactente , Humanos , Pré-Escolar , SARS-CoV-2/metabolismo , Multiômica , Citocinas/metabolismo , Interferon-alfa , Imunidade nas Mucosas
2.
Eur J Immunol ; 53(2): e2250190, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36480793

RESUMO

T follicular helper (TFH ) cells play an essential role in promoting B cell responses and antibody affinity maturation in germinal centers (GC). A subset of memory CD4+ T cells expressing the chemokine receptor CXCR5 has been described in human blood as phenotypically and clonally related to GC TFH cells. However, the antigen specificity and relationship of these circulating TFH (cTFH ) cells with other memory CD4+ T cells remain poorly defined. Combining antigenic stimulation and T cell receptor (TCR) Vß sequencing, we found T cells specific to tetanus toxoid (TT), influenza vaccine (Flu), or Candida albicans (C.alb) in both cTFH and non-cTFH subsets, although with different frequencies and effector functions. Interestingly, cTFH and non-cTFH cells specific for C.alb or TT had a largely overlapping TCR Vß repertoire while the repertoire of Flu-specific cTFH and non-cTFH cells was distinct. Furthermore, Flu-specific but not C.alb-specific PD-1+ cTFH cells had a "GC TFH -like" phenotype, with overexpression of IL21, CXCL13, and BCL6. Longitudinal analysis of serial blood donations showed that Flu-specific cTFH and non-cTFH cells persisted as stable repertoires for years. Collectively, our study provides insights on the relationship of cTFH with non-cTFH cells and on the heterogeneity and persistence of antigen-specific human cTFH cells.


Assuntos
Células T Auxiliares Foliculares , Linfócitos T Auxiliares-Indutores , Humanos , Linfócitos B , Centro Germinativo , Receptores de Antígenos de Linfócitos T
3.
BMC Biotechnol ; 24(1): 13, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459479

RESUMO

OBJECTIVE: Smoking was a major risk factor for chronic obstructive pulmonary disease (COPD). This study plan to explore the mechanism of Polyphyllin B in lung injury induced by cigarette smoke (CSE) in COPD. METHODS: Network pharmacology and molecular docking were applied to analyze the potential binding targets for Polyphyllin B and COPD. Commercial unfiltered CSE and LPS were used to construct BEAS-2B cell injury in vitro and COPD mouse models in vivo, respectively, which were treated with Polyphyllin B or fecal microbiota transplantation (FMT). CCK8, LDH and calcein-AM were used to detect the cell proliferation, LDH level and labile iron pool. Lung histopathology, Fe3+ deposition and mitochondrial morphology were observed by hematoxylin-eosin, Prussian blue staining and transmission electron microscope, respectively. ELISA was used to measure inflammation and oxidative stress levels in cells and lung tissues. Immunohistochemistry and immunofluorescence were applied to analyze the 4-HNE, LC3 and Ferritin expression. RT-qPCR was used to detect the expression of FcRn, pIgR, STAT3 and NCOA4. Western blot was used to detect the expression of Ferritin, p-STAT3/STAT3, NCOA4, GPX4, TLR2, TLR4 and P65 proteins. 16S rRNA gene sequencing was applied to detect the gut microbiota. RESULTS: Polyphyllin B had a good binding affinity with STAT3 protein, which as a target gene in COPD. Polyphyllin B inhibited CS-induced oxidative stress, inflammation, mitochondrial damage, and ferritinophagy in COPD mice. 16S rRNA sequencing and FMT confirmed that Akkermansia and Escherichia_Shigella might be the potential microbiota for Polyphyllin B and FMT to improve CSE and LPS-induced COPD, which were exhausted by the antibiotics in C + L and C + L + P mice. CSE and LPS induced the decrease of cell viability and the ferritin and LC3 expression, and the increase of NCOA4 and p-STAT3 expression in BEAS-2B cells, which were inhibited by Polyphyllin B. Polyphyllin B promoted ferritin and LC3II/I expression, and inhibited p-STAT3 and NCOA4 expression in CSE + LPS-induced BEAS-2B cells. CONCLUSION: Polyphyllin B improved gut microbiota disorder and inhibited STAT3/NCOA4 pathway to ameliorate lung tissue injury in CSE and LPS-induced mice.


Assuntos
Fumar Cigarros , Microbioma Gastrointestinal , Lesão Pulmonar , Doença Pulmonar Obstrutiva Crônica , Animais , Camundongos , Linhagem Celular , Fumar Cigarros/efeitos adversos , Ferritinas/metabolismo , Inflamação/patologia , Lipopolissacarídeos/efeitos adversos , Pulmão , Lesão Pulmonar/complicações , Lesão Pulmonar/metabolismo , Lesão Pulmonar/patologia , Simulação de Acoplamento Molecular , Doença Pulmonar Obstrutiva Crônica/terapia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , RNA Ribossômico 16S , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
4.
New Phytol ; 242(2): 641-657, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38379453

RESUMO

Nitrate is the main source of nitrogen (N) available to plants and also is a signal that triggers complex regulation of transcriptional networks to modulate a wide variety of physiological and developmental responses in plants. How plants adapt to soil nitrate fluctuations is a complex process involving a fine-tuned response to nitrate provision and N starvation, the molecular mechanisms of which remain largely uncharted. Here, we report that the wheat transcription factor TaLBD41 interacts with the nitrate-inducible transcription factor TaNAC2 and is repressed by nitrate provision. Electrophoretic mobility shift assay and dual-luciferase system show that the TaLBD41-NAC2 interaction confers homeostatic coordination of nitrate uptake, reduction, and assimilation by competitively binding to TaNRT2.1, TaNR1.2, and TaNADH-GOGAT. Knockdown of TaLBD41 expression enhances N uptake and assimilation, increases spike number, grain yield, and nitrogen harvest index under different N supply conditions. We also identified an elite haplotype of TaLBD41-2B associated with increased spike number and grain yield. Our study uncovers a novel mechanism underlying the interaction between two transcription factors in mediating wheat adaptation to nitrate availability by antagonistically regulating nitrate uptake and assimilation, providing a potential target for designing varieties with efficient N use in wheat (Triticum aestivum).


Assuntos
Nitratos , Nitrogênio , Nitratos/metabolismo , Nitrogênio/metabolismo , Transporte Biológico , Grão Comestível/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
5.
Nature ; 560(7720): 595-600, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30111841

RESUMO

Enhancing global food security by increasing the productivity of green revolution varieties of cereals risks increasing the collateral environmental damage produced by inorganic nitrogen fertilizers. Improvements in the efficiency of nitrogen use of crops are therefore essential; however, they require an in-depth understanding of the co-regulatory mechanisms that integrate growth, nitrogen assimilation and carbon fixation. Here we show that the balanced opposing activities and physical interactions of the rice GROWTH-REGULATING FACTOR 4 (GRF4) transcription factor and the growth inhibitor DELLA confer homeostatic co-regulation of growth and the metabolism of carbon and nitrogen. GRF4 promotes and integrates nitrogen assimilation, carbon fixation and growth, whereas DELLA inhibits these processes. As a consequence, the accumulation of DELLA that is characteristic of green revolution varieties confers not only yield-enhancing dwarfism, but also reduces the efficiency of nitrogen use. However, the nitrogen-use efficiency of green revolution varieties and grain yield are increased by tipping the GRF4-DELLA balance towards increased GRF4 abundance. Modulation of plant growth and metabolic co-regulation thus enables novel breeding strategies for future sustainable food security and a new green revolution.


Assuntos
Agricultura/métodos , Produtos Agrícolas/metabolismo , Desenvolvimento Vegetal , Desenvolvimento Sustentável , Compostos de Amônio/metabolismo , Ciclo do Carbono , Nitrogênio/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Grãos Integrais/crescimento & desenvolvimento , Grãos Integrais/metabolismo
6.
Health Expect ; 27(1): e13990, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38367247

RESUMO

BACKGROUND: With the growing challenge of an aging population, addressing the needs of elderly individuals who face living difficulties and lack family support becomes increasingly difficult. Volunteer services are crucial in this context, yet their effectiveness is hindered by unclear service scopes and uncertain volunteer inclinations. AIM: To explore the role and specific preference of volunteers with nursing backgrounds in support of older adults living in the urban community. DESIGN, SETTING AND PARTICIPANTS: A descriptive qualitative study was conducted between September and October 2022. Twenty-three participants (hospital nurses [10], community nurses [4], nursing teachers [4] and nursing students [5]) were selected. Data analysis followed conventional content analysis. RESULTS: Nine major themes were identified based on interview data. Four themes described the service scope of nursing volunteers: (1) environment domain, (2) physiological domain, (3) psychosocial domain and (4) health-related behaviours domain. Another five themes highlighted the service inclination of these volunteers: (1) service frequency, (2) service duration per person/time, (3) service coverage, (4) service place and (5) service object. CONCLUSION: This study clarifies the service focus and scope of necessary support for volunteers, exploring the potential service capabilities of scarce volunteers to the greatest extent. Meanwhile, the results of this study also provide a foundation for stakeholders to fully exploit the synergy. The important findings of this study will help the government and relevant authorities better understand the service attributes of nursing volunteers, allowing them to develop detailed training plans and provide nursing volunteers with targeted support and assistance to meet the health expectations of urban community-living older adults in need. PATIENT OR PUBLIC CONTRIBUTION: Developing research questions, participation and conduct and provision and interpretation of evidence.


Assuntos
Voluntários , Idoso , Humanos , Pesquisa Qualitativa , Vida Independente
7.
Inflammopharmacology ; 32(5): 3079-3098, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38977646

RESUMO

BACKGROUND: Ulcerative colitis (UC) is a chronic inflammatory disease of the colon. Ginsenoside may be an ideal agent for UC treatment. However, its efficacy and safety are unknown. We aim to conduct a systematic evaluation to assess the effects and potential mechanisms of ginsenosides in animal models of UC. METHODS: Six electronic databases will be searched (PubMed, Embase, Web of Science, China Knowledge Network (CNKI), China Science and Technology Journal Database (CQVIP), and Wanfang Data Knowledge). SYRCLE list will be used to assess the quality of literature, and STATA 15.1 for data analysis. Time-dose effects analysis will be used to reveal the time-dosage response relations between ginsenosides and UC. RESULTS: Ultimately, fifteen studies involving 300 animals were included. Preliminary evidence was shown that ginsenosides could reduce Disease Activity Index (DAI) scores, weight loss, histological colitis score (HCS), spleen weight, Malondialdehyde (MDA), Myeloperoxidase (MPO) activity, interleukin-1ß (IL-1ß), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α) and increase colon length (CL), myeloperoxidase (GSH), interleukin 4 (IL-4), interleukin 10 (IL-10), Zonula Occludens-1 (ZO-1) and occludin. Results of time-dose interval analysis indicated that ginsenosides at a dosage of 5-200 mg/kg with an intervention time of 7-28 days were relatively effective. CONCLUSIONS: Preclinical evidence suggests that ginsenoside is a novel treatment for UC. And the mechanisms of ginsenosides in treating UC may involve anti-inflammatory, antioxidant, barrier protection, intestinal flora regulation, and immune regulation. Although, due to the high heterogeneity, further large-scale and high-quality preclinical studies are needed to examine the protection of ginsenosides against UC.


Assuntos
Colite Ulcerativa , Ginsenosídeos , Colite Ulcerativa/tratamento farmacológico , Ginsenosídeos/farmacologia , Animais , Humanos , Substâncias Protetoras/farmacologia , Modelos Animais de Doenças
8.
Opt Express ; 31(7): 11239-11248, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37155764

RESUMO

Stable propagation of multifilament arrays in transparent bulk media with adjustable separation distances between adjacent child filaments has always been desired for advanced manufacturing. Here, we report on the generation of an ionization-induced volume plasma grating (VPG) by the interaction of two batches of noncollinearly propagating arrays of multiple filaments (AMF). The VPG can externally arrange the propagation of the pulses along regular plasma waveguides via spatial reconstruction of electrical fields, which is compared with the self-formation of randomly distributed multiple filamentation originated from noises. The separation distances of filaments in VPG are controllable by readily changing the crossing angle of the excitation beams. In addition, an innovative method to efficiently fabricate multidimensional grating structures in transparent bulk media through laser modification using VPG was demonstrated.

9.
Plant Biotechnol J ; 20(8): 1606-1621, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35514029

RESUMO

Genetically enhancing drought tolerance and nutrient use efficacy enables sustainable and stable wheat production in drought-prone areas exposed to water shortages and low soil fertility, due to global warming and declining natural resources. In this study, wheat plants, exhibiting improved drought tolerance and N-use efficacy, were developed by introducing GmTDN1, a gene encoding a DREB-like transcription factor, into two modern winter wheat varieties, cv Shi4185 and Jimai22. Overexpressing GmTDN1 in wheat resulted in significantly improved drought and low-N tolerance under drought and N-deficient conditions in the greenhouse. Field trials conducted at three different locations over a period of 2-3 consecutive years showed that both Shi4185 and Jimai22 GmTDN1 transgenic lines were agronomically superior to wild-type plants, and produced significantly higher yields under both drought and N-deficient conditions. No yield penalties were observed in these transgenic lines under normal well irrigation conditions. Overexpressing GmTDN1 enhanced photosynthetic and osmotic adjustment capacity, antioxidant metabolism, and root mass of wheat plants, compared to those of wild-type plants, by orchestrating the expression of a set of drought stress-related genes as well as the nitrate transporter, NRT2.5. Furthermore, transgenic wheat with overexpressed NRT2.5 can improve drought tolerance and nitrogen (N) absorption, suggesting that improving N absorption in GmTDN1 transgenic wheat may contribute to drought tolerance. These findings may lead to the development of new methodologies with the capacity to simultaneously improve drought tolerance and N-use efficacy in cereal crops to ensure sustainable agriculture and global food security.


Assuntos
Secas , Triticum , Regulação da Expressão Gênica de Plantas , Fotossíntese , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Triticum/genética , Triticum/metabolismo
10.
Xenobiotica ; 52(7): 718-728, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36227237

RESUMO

Curcumin, the main bioactive component of turmeric, has a wild range of beneficial effects on central nervous diseases, including anti-Alzheimer's disease, antioxidant stress, and anti-inflammation. Currently, it has been demonstrated the anti-epileptic potential. However, curcumin has poor water solubility, high sensitivity to light and heat, and low absorption, which results in low bioavailability and greatly limits the clinical application of curcumin, as well as the elusive effects in anti-epileptic treatment.This study aimed to develop a curcumin hydroxypropyl-ß-cyclodextrin inclusion complex (CUR-HP-ß-CD) to improve its bioavailability and facilitate its potential development as an anti-epileptic drug. The CUR-HP-ß-CD was generated by the solvent evaporation method, which has efficient entrapment, high solubility, and facilitated bioavailability and brain distribution.The solubility of the CUR-HP-ß-CD was 63.5, 60.1, and 52.9 times that of the unformulated curcumin in H2O, HCl (pH 1.2), and PBS (pH 6.8), respectively. The bioavailability of CUR-HP-ß-CD is improved 2.8 times and 38.7 folds higher brain concentrations. Moreover, the therapeutic anti-epileptic effects of CUR-HP-ß-CD were much more effective in pentylenetetrazol (PTZ)-induced zebrafish and mouse models.This study showed a simple and reproducible strategy to effectively improve the bioavailability and therapeutic effects of curcumin, which could be potentially used in epilepsy treatment.


Assuntos
Curcumina , Epilepsia , Animais , Camundongos , 2-Hidroxipropil-beta-Ciclodextrina , Curcumina/farmacologia , Peixe-Zebra , Epilepsia/tratamento farmacológico
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