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1.
Nucleic Acids Res ; 52(D1): D1588-D1596, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37933857

RESUMO

Perennial woody plants hold vital ecological significance, distinguished by their unique traits. While significant progress has been made in their genomic and functional studies, a major challenge persists: the absence of a comprehensive reference platform for collection, integration and in-depth analysis of the vast amount of data. Here, we present PPGR (Resource for Perennial Plant Genomes and Regulation; https://ngdc.cncb.ac.cn/ppgr/) to address this critical gap, by collecting, integrating, analyzing and visualizing genomic, gene regulation and functional data of perennial plants. PPGR currently includes 60 species, 847 million protein-protein/TF (transcription factor)-target interactions, 9016 transcriptome samples under various environmental conditions and genetic backgrounds. Noteworthy is the focus on genes that regulate wood production, seasonal dormancy, terpene biosynthesis and leaf senescence representing a wealth of information derived from experimental data, literature mining, public databases and genomic predictions. Furthermore, PPGR incorporates a range of multi-omics search and analysis tools to facilitate browsing and application of these extensive datasets. PPGR represents a comprehensive and high-quality resource for perennial plants, substantiated by an illustrative case study that demonstrates its capacity in unraveling gene functions and shedding light on potential regulatory processes.


Assuntos
Bases de Dados Genéticas , Genoma de Planta , Genômica , Plantas/genética , Transcriptoma
2.
Mol Psychiatry ; 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704506

RESUMO

Autism spectrum disorder (ASD) encompasses a range of neurodevelopmental conditions. Different mutations on a single ASD gene contribute to heterogeneity of disease phenotypes, possibly due to functional diversity of generated isoforms. SHANK2, a causative gene in ASD, demonstrates this phenomenon, but there is a scarcity of tools for studying endogenous SHANK2 proteins in an isoform-specific manner. Here, we report a point mutation on SHANK2, which is found in a patient with autism, located on exon of the SHANK2B transcript variant (NM_133266.5), hereby SHANK2BY29X. This mutation results in an early stop codon and an aberrant splicing event that impacts SHANK2 transcript variants distinctly. Induced pluripotent stem cells (iPSCs) carrying this mutation, from the patient or isogenic editing, fail to differentiate into functional dopamine (DA) neurons, which can be rescued by genetic correction. Available SMART-Seq single-cell data from human midbrain reveals the abundance of SHANK2B transcript in the ALDH1A1 negative DA neurons. We then show that SHANK2BY29X mutation primarily affects SHANK2B expression and ALDH1A1 negative DA neurons in vitro during early neuronal developmental stage. Mice knocked in with the identical mutation exhibit autistic-like behavior, decreased occupancy of ALDH1A1 negative DA neurons and decreased dopamine release in ventral tegmental area (VTA). Our study provides novel insights on a SHANK2 mutation derived from autism patient and highlights SHANK2B significance in ALDH1A1 negative DA neuron.

3.
BMC Plant Biol ; 24(1): 590, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38902595

RESUMO

BACKGROUND: The Prunus sibirica seeds with rich oils has great utilization, but contain amygdalin that can be hydrolyzed to release toxic HCN. Thus, how to effectively reduce seed amygdalin content of P. sibirica is an interesting question. Mandelonitrile is known as one key intermediate of amygdalin metabolism, but which mandelonitrile lyase (MDL) family member essential for its dissociation destined to low amygdalin accumulation in P. sibirica seeds still remains enigmatic. An integration of our recent 454 RNA-seq data, amygdalin and mandelonitrile content detection, qRT-PCR analysis and function determination is described as a critical attempt to determine key MDL and to highlight its function in governing mandelonitrile catabolism with low amygdalin accumulation in Prunus sibirica seeds for better developing edible oil and biodiesel in China. RESULTS: To identify key MDL and to unravel its function in governing seed mandelonitrile catabolism with low amygdalin accumulation in P. sibirica. Global identification of mandelonitrile catabolism-associated MDLs, integrated with the across-accessions/developing stages association of accumulative amount of amygdalin and mandelonitrile with transcriptional level of MDLs was performed on P. sibirica seeds of 5 accessions to determine crucial MDL2 for seed mandelonitrile catabolism of P. sibirica. MDL2 gene was cloned from the seeds of P. sibirica, and yeast eukaryotic expression revealed an ability of MDL2 to specifically catalyze the dissociation of mandelonitrile with the ideal values of Km (0.22 mM) and Vmax (178.57 U/mg). A combination of overexpression and mutation was conducted in Arabidopsis. Overexpression of PsMDL2 decreased seed mandelonitrile content with an increase of oil accumulation, upregulated transcript of mandelonitrile metabolic enzymes and oil synthesis enzymes (involving FA biosynthesis and TAG assembly), but exhibited an opposite situation in mdl2 mutant, revealing a role of PsMDL2-mediated regulation in seed amygdalin and oil biosynthesis. The PsMDL2 gene has shown as key molecular target for bioengineering high seed oil production with low amygdalin in oilseed plants. CONCLUSIONS: This work presents the first integrated assay of genome-wide identification of mandelonitrile catabolism-related MDLs and the comparative association of transcriptional level of MDLs with accumulative amount of amygdalin and mandelonitrile in the seeds across different germplasms and developmental periods of P. sibirica to determine MDL2 for mandelonitrile dissociation, and an effective combination of PsMDL2 expression and mutation, oil and mandelonitrile content detection and qRT-PCR assay was performed to unravel a mechanism of PsMDL2 for controlling amygdalin and oil production in P. sibirica seeds. These findings could offer new bioengineering strategy for high oil production with low amygdalin in oil plants.


Assuntos
Amigdalina , Prunus , Sementes , Amigdalina/metabolismo , Prunus/genética , Prunus/metabolismo , Prunus/enzimologia , Sementes/metabolismo , Sementes/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Óleos de Plantas/metabolismo , Aldeído Liases/metabolismo , Aldeído Liases/genética , Regulação da Expressão Gênica de Plantas
4.
J Exp Bot ; 75(8): 2545-2557, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38271585

RESUMO

Non-structural carbohydrates (NSCs) are building blocks for biomass and fuel metabolic processes. However, it remains unclear how tropical forests mobilize, export, and transport NSCs to cope with extreme droughts. We combined drought manipulation and ecosystem 13CO2 pulse-labeling in an enclosed rainforest at Biosphere 2, assessed changes in NSCs, and traced newly assimilated carbohydrates in plant species with diverse hydraulic traits and canopy positions. We show that drought caused a depletion of leaf starch reserves and slowed export and transport of newly assimilated carbohydrates below ground. Drought effects were more pronounced in conservative canopy trees with limited supply of new photosynthates and relatively constant water status than in those with continual photosynthetic supply and deteriorated water status. We provide experimental evidence that local utilization, export, and transport of newly assimilated carbon are closely coupled with plant water use in canopy trees. We highlight that these processes are critical for understanding and predicting tree resistance and ecosystem fluxes in tropical forest under drought.


Assuntos
Carbono , Floresta Úmida , Carbono/metabolismo , Ecossistema , Secas , Água/metabolismo , Árvores/metabolismo , Carboidratos , Folhas de Planta/metabolismo
5.
J Org Chem ; 89(10): 7076-7083, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38701135

RESUMO

A method has been developed for the rapid synthesis of highly substituted 3-methylpyridones via the condensation of Baylis-Hillman amines and ketones under benzoic acid catalysis. The process features readily available starting materials, broad substrate scope, high functional group tolerance, excellent regioselectivity, and gram-scale synthesis. We envision that this on-demand construction of 3-methylpyridones will provide exciting opportunities in biological research, therapeutics, and material sciences.

6.
Int J Mol Sci ; 25(4)2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38396847

RESUMO

Schima superba is a precious timber and fire-resistant tree species widely distributed in southern China. Currently, there is little knowledge related to its growth traits, especially with respect to molecular breeding. The lack of relevant information has delayed the development of modern breeding. The purpose is to identify probable functional genes involved in S. superba growth through whole transcriptome sequencing. In this study, a total of 32,711 mRNAs, 525 miRNAs, 54,312 lncRNAs, and 1522 circRNAs were identified from 10 S. superba individuals containing different volumes of wood. Four possible regulators, comprising three lncRNAs, one circRNA, and eleven key miRNAs, were identified from the regulatory networks of lncRNA-miRNA-mRNA and circRNA-miRNA-mRNA to supply information on ncRNAs. Several candidate genes involved in phenylpropane and cellulose biosynthesis pathways, including Ss4CL2, SsCSL1, and SsCSL2, and transcription factors, including SsDELLA2 (SsSLR), SsDELLA3 (SsSLN), SsDELLA5 (SsGAI-like2), and SsNAM1, were identified to reveal the molecular regulatory mechanisms regulating the growth traits of S. superba. The results not merely provide candidate functional genes related to S. superba growth trait and will be useful to carry out molecular breeding, but the strategy and method also provide scientists with an effective approach to revealing mechanisms behind important economic traits in other species.


Assuntos
MicroRNAs , RNA Longo não Codificante , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Circular/genética , RNA Longo não Codificante/genética , Melhoramento Vegetal , Redes Reguladoras de Genes
7.
Int J Mol Sci ; 25(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38542472

RESUMO

In recent years, the field of biology has witnessed a surge of interest in genomics research due to the advancements in biotechnology. Gene expression pattern analysis plays a crucial role in this research, as it enables us to understand the regulatory mechanism of gene expression and the associated biological processes. Real-time quantitative polymerase chain reaction (q-PCR) is an efficient method to analyze the gene expression patterns, for which accuracy relies on the standardized analysis of reference genes. However, numerous studies have shown that no reference gene is universal in all conditions, so screening a suitable reference gene under certain conditions is of great importance. Cinnamomum burmannii (C. burmannii) is rich in volatile components and has high medicinal and economic value. However, knowledge of the screening of reference genes for the gene expression analysis of C. burmannii is insufficient. Aiming at this problem, we evaluated and screened the reference genes in C. burmannii under different experimental conditions, including different abiotic stresses (Cold-treated, PEG-treated and Nacl-treated), different tissues, leaves at different developmental stages and different chemical types. In this study, different algorithms (∆Ct, geNorm, NormFinder and BestKeeper) were used to evaluate the stability of the candidate reference genes, and RefFinder further merged the output data to screen out the optimum reference gene under various experimental conditions in C. burmannii. The results showed that the optimal reference gene number for gene standardization was 2 under different experimental conditions. RPL27|RPS15 was the most suitable combination under the Nacl-treated and PEG-treated samples. RPL27|APT was the optimum combination under the Cold-treated samples. The optimal combinations of other samples were EF1α|ACT7 for different tissues, eIF-5A|Gllα for different borneol clones in C. burmannii, RPS15|ACT7 for leaves at different developmental stages and RPS15|TATA for all samples. Additionally, two terpenoid synthesis-related genes (CbWRKY4 and CbDXS2) were standardized to verify the feasibility of the selected reference genes under different experimental conditions. This study will be helpful for the subsequent molecular genetic mechanism study of C. burmannii.


Assuntos
Cinnamomum , Regulação da Expressão Gênica de Plantas , Cloreto de Sódio , Cinnamomum/genética , Perfilação da Expressão Gênica , Reação em Cadeia da Polimerase em Tempo Real/métodos , Padrões de Referência
8.
Int J Mol Sci ; 25(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38474323

RESUMO

This work aimed to identify the chemical compounds of Cinnamomum burmannii leaf essential oil (CBLEO) and to unravel the antibacterial mechanism of CBLEO at the molecular level for developing antimicrobials. CBLEO had 37 volatile compounds with abundant borneol (28.40%) and showed good potential to control foodborne pathogens, of which Staphylococcus aureus had the greatest inhibition zone diameter (28.72 mm) with the lowest values of minimum inhibitory concentration (1.0 µg/mL) and bactericidal concentration (2.0 µg/mL). To unravel the antibacterial action of CBLEO on S. aureus, a dynamic exploration of antibacterial growth, material leakage, ROS formation, protein oxidation, cell morphology, and interaction with genome DNA was conducted on S. aureus exposed to CBLEO at different doses (1/2-2×MIC) and times (0-24 h), indicating that CBLEO acts as an inducer for ROS production and the oxidative stress of S. aureus. To highlight the antibacterial action of CBLEO on S. aureus at the molecular level, we performed a comparative association of ROS accumulation with some key virulence-related gene (sigB/agrA/sarA/icaA/cidA/rsbU) transcription, protease production, and biofilm formation in S. aureus subjected to CBLEO at different levels and times, revealing that CBLEO-induced oxidative stress caused transcript suppression of virulence regulators (RsbU and SigB) and its targeted genes, causing a protease level increase destined for the biofilm formation and growth inhibition of S. aureus, which may be a key bactericidal action. Our findings provide valuable information for studying the antibacterial mechanism of essential oil against pathogens.


Assuntos
Cinnamomum , Óleos Voláteis , Óleos Voláteis/farmacologia , Cinnamomum/genética , Staphylococcus aureus/fisiologia , Virulência , Espécies Reativas de Oxigênio , Antibacterianos/farmacologia , Biofilmes , Estresse Oxidativo , Transcrição Gênica , Peptídeo Hidrolases/genética , Testes de Sensibilidade Microbiana
9.
BMC Plant Biol ; 23(1): 268, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37208597

RESUMO

BACKGROUND: Based on our previous studied on different provenances of Pistacia chinensis, some accessions with high quality and quantity of seed oils has emerged as novel source of biodiesel. To better develop P. chinensis seed oils as woody biodiesel, a concurrent exploration of oil content, FA profile, biodiesel yield, and fuel properties was conducted on the seeds from 5 plus germplasms to determine superior genotype for ideal biodiesel production. Another vital challenge is to unravel mechanism that govern the differences in oil content and FA profile of P. chinensis seeds across different accessions. FA biosynthesis and oil accumulation of oil plants are known to be highly controlled by the transcription factors. An integrated analysis of our recent transcriptome data, qRT-PCR detection and functional identification was performed as an attempt to highlight LEC1/WRI1-mediated transcription regulatory mechanism for high-quality oil accumulation in P. chinensis seeds. RESULTS: To select ideal germplasm and unravel high oil accumulative mechanism for developing P. chinensis seed oils as biodiesel, five plus trees (accession PC-BJ/PC-AH/PC-SX/PC-HN/PC-HB) with high-yield seeds were selected to assess the variabilities in weight, oil content, FA profile, biodiesel yield and fuel property, revealing a variation in the levels of seed oil (50.76-60.88%), monounsaturated FA (42.80-70.72%) and polyunsaturated FA (18.78-43.35%), and biodiesel yield (84.98-98.15%) across different accessions. PC-HN had a maximum values of seed weight (26.23 mg), oil (60.88%) and biodiesel yield (98.15%), and ideal proportions of C18:1 (69.94%), C18:2 (17.65%) and C18:3 (1.13%), implying that seed oils of accession PC-HN was the most suitable for ideal biodiesel production. To highlight molecular mechanism that govern such differences in oil content and FA profile of different accessions, a combination of our recent transcriptome data, qRT-PCR detection and protein interaction analysis was performed to identify a pivotal role of LEC1/WRI1-mediated transcription regulatory network in high oil accumulation of P. chinensis seeds from different accessions. Notably, overexpression of PcWRI1 or PcLEC1 from P. chinensis seeds in Arabidopsis could facilitate seed development and upregulate several genes relevant for carbon flux allocation (plastidic glycolysis and acetyl-CoA generation), FA synthesis, TAG assembly and oil storage, causing an increase in seed oil content and monounsaturated FA level, destined for biodiesel fuel property improvement. Our findings may present strategies for better developing P. chinensis seed oils as biodiesel feedstock and bioengineering its high oil accumulation. CONCLUSIONS: This is the first report on the cross-accessions assessments of P. chinensis seed oils to determine ideal accession for high-quality biodiesel production, and an effective combination of PcWRI1 or PcLEC1 overexpression, morphological assay, oil accumulation and qRT-PCR detection was applied to unravel a role of LEC1/WRI1-mediated regulatory network for oil accumulation in P. chinensis seeds, and to highlight the potential application of PcWRI1 or PcLEC1 for increasing oil production. Our finding may provide new strategies for developing biodiesel resource and molecular breeding.


Assuntos
Biocombustíveis , Pistacia , Óleos de Plantas , Arabidopsis/metabolismo , Ácidos Graxos/metabolismo , Pistacia/genética , Pistacia/metabolismo , Óleos de Plantas/metabolismo , Sementes
10.
Bioorg Chem ; 140: 106765, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37582330

RESUMO

Janus kinases (JAKs) play a critical role in modulating the function and expression of inflammatory cytokines related to rheumatoid arthritis (RA). Herein, we report the design, synthesis, and structure-activity relationships (SARs) of a series of novel quinazoline derivatives as JAK inhibitors. Among these inhibitors, compound 11n showed high potency against JAKs (JAK1/JAK2/JAK3/TYK2, IC50 = 0.40, 0.83, 2.10, 1.95 nM), desirable metabolic characters, and excellent pharmacokinetic properties. In collagen-induced arthritis (CIA) models, compound 11n exhibited significant reduction in joint swelling with good safety, which could be served as a potential therapeutic candidate for the treatment of inflammatory diseases.


Assuntos
Artrite Reumatoide , Inibidores de Janus Quinases , Humanos , Inibidores de Janus Quinases/farmacologia , Inibidores de Janus Quinases/uso terapêutico , Quinazolinas/farmacologia , Quinazolinas/uso terapêutico , Janus Quinases , Relação Estrutura-Atividade , Artrite Reumatoide/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
11.
J Anesth ; 37(6): 853-860, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37608132

RESUMO

PURPOSE: Repeated exposure of infant rhesus macaques to sevoflurane induces neurotoxicity and is associated with neurocognitive impairment in later life. We aimed to investigate the effect of repeated sevoflurane exposure on the expression of proteins in the prefrontal cortex of infant rhesus macaques by proteomics. METHODS: Rhesus macaques were exposed to sevoflurane three times, on postnatal days 7, 21 and 35. Quantitative proteomics employing LC-MS with isobaric labeling (TMT10plex), western blotting, and transmission electron microscopy (TEM) were utilized in the studies. RESULTS: The results of a proteomics investigation of the brain revealed that the proteins that were differentially expressed in rhesus macaques after sevoflurane exposures were associated mainly with mitochondrial respiration. Following multiple sevoflurane exposures, the prefrontal cortices of rhesus macaques exhibited increases in NDUFA8 and COX IV protein levels, while no alterations in mitochondrial morphology were observed through TEM. CONCLUSION: Multiple exposures to sevoflurane increased the mitochondrial protein levels in rhesus macaques.


Assuntos
Anestésicos Inalatórios , Humanos , Animais , Sevoflurano/toxicidade , Macaca mulatta , Anestésicos Inalatórios/toxicidade , Proteômica , Córtex Pré-Frontal , Expressão Gênica , Animais Recém-Nascidos
12.
Plant Cell Environ ; 45(10): 3122-3133, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35909089

RESUMO

Consequences of interactions between ectomycorrhizal fungi (EcMF) and non-mycorrhizal rhizosphere fungi (NMRF) for plant carbon (C) allocation belowground and nutrient cycling in soil remain unknown. To address this topic, we performed a mesocosm study with Norway spruce seedlings [Picea abies (L.) H. Karst] inoculated with EcMF, NMRF, or a mixture of both (MIX). 14 CO2 pulse labelling of spruce was applied to trace and visualize the 14 C incorporation into roots, rhizohyphosphere and hyphosphere. Activities and localization of enzymes involved in the C, nitrogen (N) and phosphorus (P) cycling were visualized using zymography. Spruce seedlings inoculated with EcMF and NMRF allocated more C to soils (EcMF: 10.7%; NMRF: 3.5% of total recovered C) compared to uninoculated control seedlings. The 14 C activity in the hyphosphere was highest for EcMF and lowest for NMRF. In the presence of both, NMRF and EcMF (MIX), the 14 C activity was 64% lower compared with EcMF inoculation alone. This suggests a suppressed C allocation via EcMF likely due to the competition between EcMF and NMRF for N and P. Furthermore, we observed 57% and 49% higher chitinase and leucine-aminopeptidase activities in the rhizohyphosphere of EcMF compared to the uninoculated control, respectively. In contrast, ß-glucosidase activity (14.3 nmol cm-2 h-1 ) was highest in NMRF likely because NMRF consumed rhizodeposits efficiently. This was further supported by that enzyme stoichiometry in soil with EcMF shifted to a higher investment of nutrient acquisition enzymes (e.g., chitinase, leucine-aminopeptidase, acid phosphatase) compared to NMRF inoculation, where investment in ß-glucosidase increased. In conclusion, the alleviation of EcMF from C limitation promotes higher activities of enzymes involved in the N and P cycle to cover the nutrient demand of EcMF and host seedlings. In contrast, C limitation of NMRF probably led to a shift in investment towards higher activities of enzymes involved in the C cycle.


Assuntos
Abies , Celulases , Quitinases , Micorrizas , Picea , Pinus , Aminopeptidases/metabolismo , Quitinases/metabolismo , Fungos , Leucina/metabolismo , Micorrizas/metabolismo , Picea/metabolismo , Raízes de Plantas/microbiologia , Rizosfera , Plântula/metabolismo , Solo
13.
Environ Sci Technol ; 56(3): 2021-2032, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35048708

RESUMO

As direct mediators between plants and soil, roots play an important role in metabolic responses to environmental stresses such as drought, yet these responses are vastly uncharacterized on a plant-specific level, especially for co-occurring species. Here, we aim to examine the effects of drought on root metabolic profiles and carbon allocation pathways of three tropical rainforest species by combining cutting-edge metabolomic and imaging technologies in an in situ position-specific 13C-pyruvate root-labeling experiment. Further, washed (rhizosphere-depleted) and unwashed roots were examined to test the impact of microbial presence on root metabolic pathways. Drought had a species-specific impact on the metabolic profiles and spatial distribution in Piper sp. and Hibiscus rosa sinensis roots, signifying different defense mechanisms; Piper sp. enhanced root structural defense via recalcitrant compounds including lignin, while H. rosa sinensis enhanced biochemical defense via secretion of antioxidants and fatty acids. In contrast, Clitoria fairchildiana, a legume tree, was not influenced as much by drought but rather by rhizosphere presence where carbohydrate storage was enhanced, indicating a close association with symbiotic microbes. This study demonstrates how multiple techniques can be combined to identify how plants cope with drought through different drought-tolerance strategies and the consequences of such changes on below-ground organic matter composition.


Assuntos
Secas , Raízes de Plantas , Metabolômica , Raízes de Plantas/metabolismo , Plantas , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Estresse Fisiológico
14.
J Neurosci Res ; 98(10): 1968-1986, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32594561

RESUMO

Microglia populate the early developing brain and mediate pruning of the central synapses. Yet, little is known on their functional significance in shaping the developing cortical circuits. We hypothesize that the developing cortical circuits require microglia for proper circuit maturation and connectivity, and as such, ablation of microglia during the cortical critical period may result in a long-lasting circuit abnormality. We administered PLX3397, a colony-stimulating factor 1 receptor inhibitor, to mice starting at postnatal day 14 and through P28, which depletes >75% of microglia in the visual cortex (VC). This treatment largely covers the critical period (P19-32) of VC maturation and plasticity. Patch clamp recording in VC layer 2/3 (L2/3) and L5 neurons revealed increased mEPSC frequency and reduced amplitude, and decreased AMPA/NMDA current ratio, indicative of altered synapse maturation. Increased spine density was observed in these neurons, potentially reflecting impaired synapse pruning. In addition, VC intracortical circuit functional connectivity, assessed by laser scanning photostimulation combined with glutamate uncaging, was dramatically altered. Using two photon longitudinal dendritic spine imaging, we confirmed that spine elimination/pruning was diminished during VC critical period when microglia were depleted. Reduced spine pruning thus may account for increased spine density and disrupted connectivity of VC circuits. Lastly, using single-unit recording combined with monocular deprivation, we found that ocular dominance plasticity in the VC was obliterated during the critical period as a result of microglia depletion. These data establish a critical role of microglia in developmental cortical synapse pruning, maturation, functional connectivity, and critical period plasticity.


Assuntos
Ácido Glutâmico , Microglia/fisiologia , Rede Nervosa/crescimento & desenvolvimento , Plasticidade Neuronal/fisiologia , Sinapses/fisiologia , Córtex Visual/crescimento & desenvolvimento , Animais , Período Crítico Psicológico , Feminino , Ácido Glutâmico/metabolismo , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Rede Nervosa/metabolismo , Técnicas de Cultura de Órgãos , Córtex Visual/metabolismo
15.
Biol Blood Marrow Transplant ; 25(10): 2040-2044, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31207293

RESUMO

As an inherited anemia, thalassemia major (TM) is currently only curable with allogeneic hematopoietic stem cell transplantation (allo-HSCT). Here we report an allo-HSCT protocol for patients with TM who received a combination of granulocyte colony-stimulating factor-primed bone marrow and peripheral blood stem cells (G-BM & PBSCs) from a matched sibling donor (MSD). The conditioning regimen consisted of i.v. busulfan, cyclophosphamide, fludarabine, and antithymocyte globulin. Chimerism analysis was performed for all patients. Immunosuppressive treatment was terminated if rejection was suspected, and donor lymphocyte infusion was administered once no response was observed. A total of 184 patients with TM were enrolled in the study between July 2007 and July 2018. The cumulative incidence of grade II-IV acute graft-versus-host disease (GVHD) was 13.1%, and that of moderate or severe chronic GVHD was 5.7%. The cumulative incidence of graft rejection was .6%. In the total cohort, the 3-year overall survival, thalassemia-free survival, and GVHD-free, relapse-free survival were 97.8%, 97.3%, and 89.5%, respectively. Collectively, our results indicate that G-BM & PBSCs from an MSD is be a good stem cell source for patients with TM undergoing allo-HSCT.


Assuntos
Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/métodos , Condicionamento Pré-Transplante/métodos , Talassemia beta/tratamento farmacológico , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Fator Estimulador de Colônias de Granulócitos/farmacologia , Humanos , Masculino , Estudos Prospectivos , Irmãos , Adulto Jovem
16.
Small ; 15(50): e1905166, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31725197

RESUMO

Scalable and sustainable solar hydrogen production via photocatalytic water splitting requires extremely active and stable light-harvesting semiconductors to fulfill the stringent requirements of suitable energy band position and rapid interfacial charge transfer process. Motivated by this point, increasing attention has been given to the development of photocatalysts comprising intimately interfaced photoabsorbers and cocatalysts. Herein, a simple one-step approach is reported to fabricate a high-efficiency photocatalytic system, in which single-site dispersed iron atoms are rationally integrated on the intrinsic structure of the porous crimped graphitic carbon nitride (g-C3 N4 ) polymer. A detailed analysis of the formation process shows that a stable complex is generated by spontaneously coordinating dicyandiamidine nitrate with iron ions in isopropanol, thus leading to a relatively complicated polycondensation reaction upon thermal treatment. The correlation of experimental and computational results confirms that optimized electronic structures of Fe@g-C3 N4 with an appropriate d-band position and negatively shifting Fermi level can be achieved, which effectively gains the reducibility of electrons and creates more active sites for the photocatalytic reactions. As a result, the Fe@g-C3 N4 exhibits a highlighted intramolecular synergistic effect, performing greatly enhanced solar-photon-driven activities, including excellent photocatalytic hydrogen evolution rate (3390 µmol h-1 g-1 , λ > 420 nm) and a reliable apparent quantum efficiency value of 6.89% at 420 nm.

17.
Appl Environ Microbiol ; 85(12)2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-30979833

RESUMO

Deforestation has a substantial impact on aboveground biodiversity, but the response of belowground soil fungi remains poorly understood. In a tropical montane rainforest in southwestern China, plots were established along a forest degradation gradient ranging from mature and regenerated forests to open land to examine the impacts of forest degradation and deforestation on ecosystem diversity and function. Here, we evaluated the changes in belowground fungal diversity and community composition using a metabarcoding approach. Soil saprotrophic fungal richness declined with increasing forest disturbance. For example, Penicillium spp. (phosphorus [P]-solubilizing fungi) dominated in mature forest but were less abundant in regenerating forests and showed the lowest abundance in open land sites. Conversely, the abundance of facultative pathogenic fungi increased along the disturbance gradient. The decline in soil saprophytic fungi may be a direct result of forest disturbance or it may be associated with increased availability of soil phosphorus indirectly through an increase in soil pH. The increase in abundance of facultative pathogenic fungi may be related to reduced competition with saprotrophic fungi, changes in microclimate, or increased spore rain. These results demonstrate a loss of dominant P-solubilizing saprotrophic fungi along the disturbance gradient, indicating a change from soil P limitation in mature tropical forests to soil C limitation in deforested sites. The increased prevalence of pathogenic fungi may inhibit plant succession following deforestation. Overall, this research demonstrates that soil fungi can be used as a sensitive indicator for soil health to evaluate the consequences of forest disturbance.IMPORTANCE The soil fungal functional group changes in response to forest disturbance and indicates a close interaction between the aboveground plant community and the belowground soil biological community. Soil saprotrophic fungi declined in relative abundance with increasing forest disturbance. At the same time, the relative abundance of facultative pathogenic fungi increased. The loss of saprotrophic fungal richness and abundance may have been a direct result of forest disturbance or an indirect result of changes in soil pH and soil P. Furthermore, the dominant P-solubilizing saprotrophic fungi were replaced by diverse facultative pathogenic fungi, which have weaker C decomposition ability. These changes potentially indicate a shift from soil phosphate limitation to carbon limitation following deforestation. This study suggests that changes in fungal functional group composition can be used as an indicator of the effects of forest disturbance on soil carbon and nutrients.


Assuntos
Conservação dos Recursos Naturais , Florestas , Fungos/fisiologia , Microbiota , China
18.
Eur J Haematol ; 103(4): 342-350, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31276236

RESUMO

BACKGROUND: The clinical outcome of hematopoietic stem cell transplantation (HSCT) in those with severe beta-thalassemia (ß-TM) is closely related to post-transplantation immune reconstitution (IR). However, the data on the IR in these settings are scarce. METHODS: A prospective analysis of the clinical outcome and IR in 47 children with severe ß-TM who underwent in vivo T-cell depletion myeloablative conditioning and matched sibling donor HSCT was performed. Immune reconstitution, including immune cell subset counts, as well as the generation of new T and B cells assays after HSCT, was measured. RESULTS: In the first year after HSCT, bacterial infections and cytomegalovirus (CMV) reactivation were observed in 70.2% and 36.2% of the patients, respectively. In the same period, poor CD4+ T-cell recovery was observed. The B cells recovered within 6 months. Natural killer (NK) cells recovered as early as 1 month, but their function was defective. Cord blood and bone marrow (CB + BM) group had slower T-cell recovery, and higher B cells and NK cells in comparison with peripheral blood and bone marrow (PB + BM) group. CONCLUSIONS: The high incidence of infection within 1 year after in vivo T-cell depletion myeloablative conditioning HSCT in severe ß-TM was consistent with poor IR.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Reconstituição Imune , Depleção Linfocítica , Linfócitos T/imunologia , Condicionamento Pré-Transplante , Talassemia beta/imunologia , Talassemia beta/terapia , Linfócitos B/imunologia , Medula Óssea/imunologia , Medula Óssea/metabolismo , Medula Óssea/patologia , Criança , Pré-Escolar , Feminino , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Imunofenotipagem , Células Matadoras Naturais/imunologia , Contagem de Linfócitos , Depleção Linfocítica/métodos , Masculino , Linfócitos T/metabolismo , Condicionamento Pré-Transplante/métodos
19.
Hemoglobin ; 42(4): 225-230, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30821197

RESUMO

Fetal hemoglobin (Hb F, α2γ2) is a potent genetic modifier of the severity of ß-thalassemia (ß-thal) and sickle cell anemia. Differences in the levels of HbF that persist into adulthood affect the severity of sickle cell disease and the ß-thal syndromes. B-cell lymphoma 11 A (BCL11A) is a potent silencer of HbF. Here, we reactivated γ-globin expression by down-regulating BCL11A to alleviate anemia in the ß-thal major (ß-TM) patients. BCL11A were down-regulated by lentiviral RNAi (RNA interference) in the K562 cell line and an in vitro culture model of human erythropoiesis in which erythroblasts are derived from the normal donor mononuclear cells (MNC) or ß-TM MNC. The expression of γ-globin were analyzed by qPCR (quantitative real-time polymerase chain reaction) and Western blot techniques. Our data showed that down-regulation of BCL11A induces γ-globin production in the K562 cell line and human erythrocytes from normal donors and ß-TM donors, without altering erythroid maturation. This is the first report on γ-globin induction by down-regulation of BCL11A in human erythroblasts derived from ß-TM.


Assuntos
Proteínas de Transporte/farmacologia , Células Eritroides/metabolismo , Proteínas Nucleares/farmacologia , Talassemia beta/patologia , gama-Globinas/efeitos dos fármacos , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Eritroblastos/metabolismo , Hemoglobina Fetal , Humanos , Células K562 , Proteínas Repressoras , Ativação Transcricional/efeitos dos fármacos , Talassemia beta/metabolismo
20.
Zhongguo Zhong Yao Za Zhi ; 43(20): 4055-4061, 2018 Oct.
Artigo em Zh | MEDLINE | ID: mdl-30486530

RESUMO

This research preliminarily discusses the relations of Dendrobium system growth through chloroplast gene rbcL, matK and the nuclear genome ITS2. The DNA barcoding universal sequence for authentication of the Dendrobium medical plants was slected and the possibility concerning utilizing the DNA barcoding to distinguish the D. huoshanenseand its adulterants was analyzed. Using the universal primer pair of ITS2, rbcL and matK, series of extended sequencing in the Dendrobium were conducted. Meanwhile, considering the different index about amplification and sequencing success rate of each sequence, the intraspecific and interspecific aberrance, the employment of BioEdit and MEGA 5.0 software were applied to establish the systematic tree of the NJ molecular and evaluate the diversified authentication capability of various sequences. The consequence demonstrates that the sequence of ITS2 is not only the largest one both in the intraspecific and interspecific aberrance of the Dendrobium but also has obvious barcoding gap. Considering the few overlap between the intraspecific and interspecific aberrance and the highest percentage regarding the formation of unilateral branch in diverse Dendrobium which have different ITS2 sequences, it can differentiate the species of Dendrobium. Furthermore, due to the inferior success rate of the rbcL and thematK and the lower reliability of NJ systematic tree, the percentage of the unilateral species which are generated by the systematic tree of rbcL and matK sequences is deficient. Therefore, the sequence of ITS2 can serves as DNA barcoding to distinguish the D. huoshanense, the D. moniliform and the D. officinale.


Assuntos
Código de Barras de DNA Taxonômico , Dendrobium/classificação , Contaminação de Medicamentos , Preparações de Plantas/normas , DNA de Plantas/genética , Plantas Medicinais/classificação , Reprodutibilidade dos Testes
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