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1.
Cell Mol Biol (Noisy-le-grand) ; 70(6): 233-237, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38836656

RESUMO

Nur77 is a member of the NR4A subfamily of orphan nuclear receptors that is expressed and has a function within the immune system. This study aimed to investigate the role of Nur77 in hypoxic pulmonary hypertension. SPF male SD rats were exposed in hypobaric chamber simulating 5000 m high altitude for 0, 3, 7, 14, 21 or 28 days. Rat pulmonary artery smooth muscle cells (RPASMCs) were cultured under normoxic conditions (5% CO2-95% ambient air) or hypoxic conditions (5% O2 for 6 h, 12 h, 24 h, 48 h). Hypoxic rats developed pulmonary arterial remodeling and right ventricular hypertrophy with significantly increased pulmonary arterial pressure. The levels of Nur77, HIF-1α and PNCA were upregulated in pulmonary arterial smooth muscle from hypoxic rats. Silencing of either Nur77 or HIF-1α attenuated hypoxia-induced proliferation. Silencing of HIF-1α down-regulated Nur77 protein level, but Nur77 silence did not reduce HIF-1α. Nur77 was not con-immunoprecipitated with HIF-1α. This study demonstrated that Nur77 acted as a downstream regulator of HIF-1α under hypoxia, and plays a critical role in the hypoxia-induced pulmonary vascular remodeling, which is regulated by HIF-1α. Nur77 maybe a novel target of HPH therapy.


Assuntos
Hipertensão Pulmonar , Subunidade alfa do Fator 1 Induzível por Hipóxia , Hipóxia , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares , Artéria Pulmonar , Ratos Sprague-Dawley , Remodelação Vascular , Animais , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Remodelação Vascular/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Masculino , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/genética , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Hipóxia/metabolismo , Proliferação de Células , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Ratos , Hipertrofia Ventricular Direita/metabolismo , Hipertrofia Ventricular Direita/patologia , Hipertrofia Ventricular Direita/fisiopatologia , Hipertrofia Ventricular Direita/genética , Células Cultivadas
2.
Neuroimage ; 261: 119532, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35931307

RESUMO

Natural images containing affective scenes are used extensively to investigate the neural mechanisms of visual emotion processing. Functional fMRI studies have shown that these images activate a large-scale distributed brain network that encompasses areas in visual, temporal, and frontal cortices. The underlying spatial and temporal dynamics, however, remain to be better characterized. We recorded simultaneous EEG-fMRI data while participants passively viewed affective images from the International Affective Picture System (IAPS). Applying multivariate pattern analysis to decode EEG data, and representational similarity analysis to fuse EEG data with simultaneously recorded fMRI data, we found that: (1) ∼80 ms after picture onset, perceptual processing of complex visual scenes began in early visual cortex, proceeding to ventral visual cortex at ∼100 ms, (2) between ∼200 and ∼300 ms (pleasant pictures: ∼200 ms; unpleasant pictures: ∼260 ms), affect-specific neural representations began to form, supported mainly by areas in occipital and temporal cortices, and (3) affect-specific neural representations were stable, lasting up to ∼2 s, and exhibited temporally generalizable activity patterns. These results suggest that affective scene representations in the brain are formed temporally in a valence-dependent manner and may be sustained by recurrent neural interactions among distributed brain areas.


Assuntos
Mapeamento Encefálico , Córtex Visual , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa , Córtex Visual/fisiologia , Percepção Visual/fisiologia
3.
Cereb Cortex ; 31(6): 3047-3063, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33594428

RESUMO

The perception of opportunities and threats in complex visual scenes represents one of the main functions of the human visual system. The underlying neurophysiology is often studied by having observers view pictures varying in affective content. It has been shown that viewing emotionally engaging, compared with neutral, pictures (1) heightens blood flow in limbic, frontoparietal, and anterior visual structures and (2) enhances the late positive event-related potential (LPP). The role of retinotopic visual cortex in this process has, however, been contentious, with competing theories predicting the presence versus absence of emotion-specific signals in retinotopic visual areas. Recording simultaneous electroencephalography-functional magnetic resonance imaging while observers viewed pleasant, unpleasant, and neutral affective pictures, and applying multivariate pattern analysis, we found that (1) unpleasant versus neutral and pleasant versus neutral decoding accuracy were well above chance level in retinotopic visual areas, (2) decoding accuracy in ventral visual cortex (VVC), but not in early or dorsal visual cortex, was correlated with LPP, and (3) effective connectivity from amygdala to VVC predicted unpleasant versus neutral decoding accuracy, whereas effective connectivity from ventral frontal cortex to VVC predicted pleasant versus neutral decoding accuracy. These results suggest that affective scenes evoke valence-specific neural representations in retinotopic visual cortex and that these representations are influenced by reentry signals from anterior brain regions.


Assuntos
Afeto/fisiologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Córtex Visual/diagnóstico por imagem , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Adolescente , Eletroencefalografia/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Estimulação Luminosa/métodos , Adulto Jovem
4.
Lancet ; 395(10224): 565-574, 2020 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-32007145

RESUMO

BACKGROUND: In late December, 2019, patients presenting with viral pneumonia due to an unidentified microbial agent were reported in Wuhan, China. A novel coronavirus was subsequently identified as the causative pathogen, provisionally named 2019 novel coronavirus (2019-nCoV). As of Jan 26, 2020, more than 2000 cases of 2019-nCoV infection have been confirmed, most of which involved people living in or visiting Wuhan, and human-to-human transmission has been confirmed. METHODS: We did next-generation sequencing of samples from bronchoalveolar lavage fluid and cultured isolates from nine inpatients, eight of whom had visited the Huanan seafood market in Wuhan. Complete and partial 2019-nCoV genome sequences were obtained from these individuals. Viral contigs were connected using Sanger sequencing to obtain the full-length genomes, with the terminal regions determined by rapid amplification of cDNA ends. Phylogenetic analysis of these 2019-nCoV genomes and those of other coronaviruses was used to determine the evolutionary history of the virus and help infer its likely origin. Homology modelling was done to explore the likely receptor-binding properties of the virus. FINDINGS: The ten genome sequences of 2019-nCoV obtained from the nine patients were extremely similar, exhibiting more than 99·98% sequence identity. Notably, 2019-nCoV was closely related (with 88% identity) to two bat-derived severe acute respiratory syndrome (SARS)-like coronaviruses, bat-SL-CoVZC45 and bat-SL-CoVZXC21, collected in 2018 in Zhoushan, eastern China, but were more distant from SARS-CoV (about 79%) and MERS-CoV (about 50%). Phylogenetic analysis revealed that 2019-nCoV fell within the subgenus Sarbecovirus of the genus Betacoronavirus, with a relatively long branch length to its closest relatives bat-SL-CoVZC45 and bat-SL-CoVZXC21, and was genetically distinct from SARS-CoV. Notably, homology modelling revealed that 2019-nCoV had a similar receptor-binding domain structure to that of SARS-CoV, despite amino acid variation at some key residues. INTERPRETATION: 2019-nCoV is sufficiently divergent from SARS-CoV to be considered a new human-infecting betacoronavirus. Although our phylogenetic analysis suggests that bats might be the original host of this virus, an animal sold at the seafood market in Wuhan might represent an intermediate host facilitating the emergence of the virus in humans. Importantly, structural analysis suggests that 2019-nCoV might be able to bind to the angiotensin-converting enzyme 2 receptor in humans. The future evolution, adaptation, and spread of this virus warrant urgent investigation. FUNDING: National Key Research and Development Program of China, National Major Project for Control and Prevention of Infectious Disease in China, Chinese Academy of Sciences, Shandong First Medical University.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Genoma Viral , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Receptores Virais/metabolismo , Betacoronavirus/metabolismo , Líquido da Lavagem Broncoalveolar/virologia , COVID-19 , China/epidemiologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/transmissão , DNA Viral/genética , Reservatórios de Doenças/virologia , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Filogenia , Pneumonia Viral/diagnóstico , Pneumonia Viral/transmissão , SARS-CoV-2 , Alinhamento de Sequência
5.
Microb Pathog ; 158: 104969, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34044047

RESUMO

Burkholderia pseudomallei is the etiological agent of melioidosis, which is an emerging infectious disease endemic to many tropical regions. Autophagy is an intrinsic cellular process that degrades cytoplasmic components and plays an important role in protecting the host against pathogens. Like many intracellular pathogens, B. pseudomallei can evade the autophagy-dependent cellular clearance. However, the underlying mechanism remains unclear. In this study, we applied a combination of multiple assays to monitor autophagy processes and found that B. pseudomallei induced an incomplete autophagic flux and eliminate autophagy clearance in macrophages by blocking autophagosome-lysosome fusion. Based on a high-throughput microarray screening, we found that LIPA (lysosomal acid LIPAse A) was downregulated during B. pseudomallei infection. MiR-146a was then identified to be specifically upregulated upon infection with B. pseudomallei and further regulated LIPA expression by interacting with 3'UTR of LIPA. Furthermore, overexpression of miR-146a contributed to the defect of autophagic flux caused by B. pseudomallei and was beneficial for the survival of B. pseudomallei in macrophages. Therefore, our findings suggest that miR-146a inhibits autophagy via posttranscriptional suppression of LIPA expression to maintain B. pseudomallei survival in macrophages.


Assuntos
Burkholderia pseudomallei , Macrófagos/microbiologia , Melioidose , MicroRNAs , Esterol Esterase , Animais , Autofagia , Burkholderia pseudomallei/genética , Células HEK293 , Humanos , Camundongos , MicroRNAs/genética , Células RAW 264.7
6.
Epilepsy Behav ; 114(Pt A): 107598, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33268020

RESUMO

INTRODUCTION: Many commonly prescribed drugs cause cognitive deficits. We investigated whether parameters of the resting-state electroencephalogram (rsEEG) are related to the severity of cognitive impairments associated with administration of the antiseizure drug topiramate (TPM) and the benzodiazepine lorazepam (LZP). METHODS: We conducted a double-blind, randomized, placebo-controlled crossover study. After a baseline visit, subjects completed three sessions at which they received either a single dose of TPM, LZP, or placebo. Four-hours after drug administration and at baseline, subjects completed a working memory (WM) task after their rsEEG was recorded. After quantifying drug-related behavioral (WM accuracy (ACC)/reaction time (RT)) and electrophysiological (alpha, theta, beta (1,2), gamma power) change for each subject, we constructed drug-specific mixed effects models of change for each WM and EEG measure. Regression models were constructed to characterize the relationship between baseline rsEEG measures and drug-related performance changes. RESULTS: Linear mixed effects models showed theta power increases in response to TPM administration. The results of the regression models revealed a number of robust relationships between baseline rsEEG parameters and TPM-related, but not LZP-related, WM impairment. CONCLUSIONS: We showed for the first time that parameters of the rsEEG are associated with the severity of TPM-related WM deficits; this suggests that rsEEG measures may have novel clinical applications in the future.


Assuntos
Disfunção Cognitiva , Eletroencefalografia , Disfunção Cognitiva/induzido quimicamente , Estudos Cross-Over , Humanos , Tempo de Reação , Topiramato
7.
Clin Infect Dis ; 71(16): 2150-2157, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-32442287

RESUMO

BACKGROUND: Thymosin alpha 1 (Tα1) had been used in the treatment of viral infections as an immune response modifier for many years. However, clinical benefits and the mechanism of Tα1 treatment for COVID-19 patients are still unclear. METHODS: We retrospectively reviewed the clinical outcomes of 76 severe COVID-19 cases admitted to 2 hospitals in Wuhan, China, from December 2019 to March 2020. The thymus output in peripheral blood mononuclear cells from COVID-19 patients was measured by T-cell receptor excision circles (TRECs). The levels of T-cell exhaustion markers programmed death-1 (PD-1) and T-cell immunoglobulin and mucin domain protein 3 (Tim-3) on CD8+ T cells were detected by flow cytometry. RESULTS: Compared with the untreated group, Tα1 treatment significantly reduced the mortality of severe COVID-19 patients (11.11% vs 30.00%, P = .044). Tα1 enhanced blood T-cell numbers in COVID-19 patients with severe lymphocytopenia. Under such conditions, Tα1 also successfully restored CD8+ and CD4+ T-cell numbers in elderly patients. Meanwhile, Tα1 reduced PD-1 and Tim-3 expression on CD8+ T cells from severe COVID-19 patients compared with untreated cases. It is of note that restoration of lymphocytopenia and acute exhaustion of T cells were roughly parallel to the rise of TRECs. CONCLUSIONS: Tα1 treatment significantly reduced mortality of severe COVID-19 patients. COVID-19 patients with counts of CD8+ T cells or CD4+ T cells in circulation less than 400/µL or 650/µL, respectively, gained more benefits from Tα1. Tα1 reversed T-cell exhaustion and recovered immune reconstitution through promoting thymus output during severe acute respiratory syndrome-coronavirus 2 infection.


Assuntos
COVID-19/mortalidade , Linfopenia/metabolismo , SARS-CoV-2/patogenicidade , Timalfasina/metabolismo , Adulto , Idoso , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , COVID-19/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Timalfasina/genética , Timo/metabolismo
8.
Glob Chang Biol ; 26(6): 3429-3442, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32215999

RESUMO

CO2 fluxes from wood decomposition represent an important source of carbon from forest ecosystems to the atmosphere, which are determined by both wood traits and climate influencing the metabolic rates of decomposers. Previous studies have quantified the effects of moisture and temperature on wood decomposition, but these effects were not separated from the potential influence of wood traits. Indeed, it is not well understood how traits and climate interact to influence wood CO2 fluxes. Here, we examined the responses of CO2 fluxes from dead wood with different traits (angiosperm and gymnosperm) to 0%, 35%, and 70% rainfall reduction across seasonal temperature gradients. Our results showed that drought significantly decreased wood CO2 fluxes, but its effects varied with both taxonomical group and drought intensity. Drought-induced reduction in wood CO2 fluxes was larger in angiosperms than gymnosperms for the 35% rainfall reduction treatment, but there was no significant difference between these groups for the 70% reduction treatment. This is because wood nitrogen density and carbon quality were significantly higher in angiosperms than gymnosperms, yielding a higher moisture sensitivity of wood decomposition. These findings were demonstrated by a significant positive interaction effect between wood nitrogen and moisture on CO2 fluxes in a structural equation model. Additionally, we ascertained that a constant temperature sensitivity of CO2 fluxes was independent of wood traits and consistent with previous estimates for extracellular enzyme kinetics. Our results highlight the key role of wood traits in regulating drought responses of wood carbon fluxes. Given that both climate and forest management might extensively modify taxonomic compositions in the future, it is critical for carbon cycle models to account for such interactions between wood traits and climate in driving dynamics of wood decomposition.


Assuntos
Secas , Madeira , Carbono , Ciclo do Carbono , Dióxido de Carbono , Ecossistema
9.
J Cogn Neurosci ; 31(12): 1933-1945, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31418335

RESUMO

Working memory capacity (WMC) measures the amount of information that can be maintained online in the face of distraction. Past work has shown that the efficiency with which the frontostriatal circuit filters out task-irrelevant distracting information is positively correlated with WMC. Recent work has demonstrated a role of posterior alpha oscillations (8-13 Hz) in providing a sensory gating mechanism. We investigated the relationship between memory load modulation of alpha power and WMC in two verbal working memory experiments. In both experiments, we found that posterior alpha power increased with memory load during memory, in agreement with previous reports. Across individuals, the degree of alpha power modulation by memory load was negatively associated with WMC, namely, the higher the WMC, the less alpha power was modulated by memory load. After the administration of topiramate, a drug known to affect alpha oscillations and have a negative impact on working memory function, the negative correlation between memory load modulation of alpha power and WMC was no longer statistically significant but still somewhat detectable. These results suggest that (1) individuals with low WMC demonstrate stronger alpha power modulation by memory load, reflecting possibly an increased reliance on sensory gating to suppress task-irrelevant information in these individuals, in contrast to their high WMC counterparts who rely more on frontal areas to perform this function and (2) this negative association between memory load modulation of alpha oscillations and WMC is vulnerable to drug-related cognitive disruption.


Assuntos
Ritmo alfa/fisiologia , Memória de Curto Prazo/fisiologia , Retenção Psicológica/fisiologia , Filtro Sensorial/fisiologia , Aprendizagem Verbal/fisiologia , Adulto , Ritmo alfa/efeitos dos fármacos , Sinais (Psicologia) , Eletroencefalografia , Feminino , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/fisiologia , Humanos , Masculino , Memória de Curto Prazo/efeitos dos fármacos , Rememoração Mental , Retenção Psicológica/efeitos dos fármacos , Filtro Sensorial/efeitos dos fármacos , Topiramato/farmacologia , Aprendizagem Verbal/efeitos dos fármacos , Adulto Jovem
10.
Neuroimage ; 183: 897-906, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30176369

RESUMO

Power (amplitude) and frequency are two important characteristics of EEG alpha oscillations (8-12 Hz). There is an extensive literature showing that alpha power can be modulated in a goal-oriented manner to either enhance or suppress sensory information processing. Only a few studies to date have examined the task-dependent modulation of alpha frequency. Instead, alpha frequency is often viewed as a trait variable, and used to characterize individual differences in cognitive functioning. We performed two experiments to examine the task-dependent modulation of alpha frequency and its functional significance. In the first experiment, high-density EEG was recorded from 21 participants performing a Sternberg working memory task. The results showed that: (1) during memory encoding, alpha frequency decreased with increasing memory load, whereas during memory retention and retrieval, alpha frequency increased with increasing memory load, (2) higher alpha frequency prior to the onset of probe was associated with longer reaction time, and (3) higher alpha frequency prior to the onset of cue or probe was associated with weaker early cue-evoked or probe-evoked neural responses. In the second experiment, simultaneous EEG-fMRI was recorded from 59 participants during resting state. An EEG-informed fMRI analysis revealed that the spontaneous fluctuations of alpha frequency, but not alpha power, were inversely associated with BOLD activity in the visual cortex. Taken together, these findings suggest that alpha frequency is task-dependent, may serve as an indicator of cortical excitability, and along with alpha power, provides more comprehensive indexing of sensory gating.


Assuntos
Ritmo alfa/fisiologia , Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Memória de Curto Prazo/fisiologia , Adulto , Eletroencefalografia/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Processamento de Sinais Assistido por Computador , Adulto Jovem
11.
Glob Chang Biol ; 24(11): 5259-5269, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29901246

RESUMO

Wood decomposition is a major component of the global carbon cycle. Decomposition rates vary across climate gradients, which is thought to reflect the effects of temperature and moisture on the metabolic kinetics of decomposers. However, decomposition rates also vary with wood traits, which may reflect the influence of stoichiometry on decomposer metabolism as well as geometry relating the surface areas that decomposers colonize with the volumes they consume. In this paper, we combined metabolic and geometric scaling theories to formalize hypotheses regarding the drivers of wood decomposition rates, and assessed these hypotheses using a global compilation of data on climate, wood traits, and wood decomposition rates. Our results are consistent with predictions from both metabolic and geometric scaling theories. Approximately half of the global variation in decomposition rates was explained by wood traits (nitrogen content and diameter), whereas only a fifth was explained by climate variables (air temperature, precipitation, and relative humidity). These results indicate that global variation in wood decomposition rates is best explained by stoichiometric and geometric wood traits. Our findings suggest that inclusion of wood traits in global carbon cycle models can improve predictions of carbon fluxes from wood decomposition.


Assuntos
Ciclo do Carbono , Clima , Madeira , Carbono/metabolismo , Nitrogênio/metabolismo , Temperatura , Madeira/metabolismo
12.
J Clin Psychopharmacol ; 38(5): 481-488, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30124584

RESUMO

PURPOSE/BACKGROUND: Topiramate (TPM) and lorazepam (LZP) are two examples of frequently prescribed medications that are associated with a high incidence of cognitive impairment; however, the factors that underlie interindividual differences in side effect profiles have not been fully characterized. Our objective was to determine whether working memory capacity (WMC), the amount of information that can be stored and manipulated in memory over short time intervals, is one such factor. METHODS/PROCEDURES: Twenty-nine healthy volunteers completed a double-blind, randomized, placebo-controlled crossover study during which they received placebo (PBO), TPM, and LZP in random order. Four hours after drug administration, a blood draw was taken to establish drug concentrations, and subjects performed a verbal working memory task while the accuracy and reaction time of their responses were recorded. Working memory capacity was calculated based on accuracy rates during the PBO session, and the role of WMC in moderating the severity of drug-related cognitive impairment was assessed by examining drug-related performance changes from PBO as a function of WMC. FINDINGS/RESULTS: Both TPM and LZP had a negative impact on task performance, although only TPM-related deficits were modulated by WMC; high WMC was associated with more severe impairments and heightened sensitivity to increasing TPM concentrations. IMPLICATIONS/CONCLUSIONS: We have identified a potential clinical risk factor, high WMC, which is associated with drug-related adverse cognitive events. These data provide objective evidence in support of clinical observations that high-functioning patients are more likely to experience severe cognitive impairments.


Assuntos
Anticonvulsivantes/efeitos adversos , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/diagnóstico , Individualidade , Memória de Curto Prazo/efeitos dos fármacos , Topiramato/efeitos adversos , Adolescente , Adulto , Disfunção Cognitiva/psicologia , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Valor Preditivo dos Testes , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Adulto Jovem
13.
Glob Chang Biol ; 23(3): 1167-1179, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27416555

RESUMO

Livestock grazing activities potentially alter ecosystem carbon (C) and nitrogen (N) cycles in grassland ecosystems. Despite the fact that numerous individual studies and a few meta-analyses had been conducted, how grazing, especially its intensity, affects belowground C and N cycling in grasslands remains unclear. In this study, we performed a comprehensive meta-analysis of 115 published studies to examine the responses of 19 variables associated with belowground C and N cycling to livestock grazing in global grasslands. Our results showed that, on average, grazing significantly decreased belowground C and N pools in grassland ecosystems, with the largest decreases in microbial biomass C and N (21.62% and 24.40%, respectively). In contrast, belowground fluxes, including soil respiration, soil net N mineralization and soil N nitrification increased by 4.25%, 34.67% and 25.87%, respectively, in grazed grasslands compared to ungrazed ones. More importantly, grazing intensity significantly affected the magnitude (even direction) of changes in the majority of the assessed belowground C and N pools and fluxes, and C : N ratio as well as soil moisture. Specifically,light grazing contributed to soil C and N sequestration whereas moderate and heavy grazing significantly increased C and N losses. In addition, soil depth, livestock type and climatic conditions influenced the responses of selected variables to livestock grazing to some degree. Our findings highlight the importance of the effects of grazing intensity on belowground C and N cycling, which may need to be incorporated into regional and global models for predicting effects of human disturbance on global grasslands and assessing the climate-biosphere feedbacks.


Assuntos
Pradaria , Gado , Ciclo do Nitrogênio , Animais , Carbono , Ciclo do Carbono , Ecossistema , Herbivoria , Nitrogênio , Poaceae , Solo
14.
Neurocase ; 23(5-6): 263-269, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29052465

RESUMO

To assess the specific roles of left middle frontal gyrus (LMFG) in word production, electrocorticography signals were recorded from an epilepsy patient when he participated in language tasks. We found three sites of LMFG showed high-gamma perturbations with distinct patterns across tasks; and neural activities elicited in the same tasks shared similar patterns, while those elicited by stimuli leading to the same articulations did not. These findings confirmed that the LMFG takes active parts in word production, and suggested that it may serve as a temporal perceptual information storage space, supporting the hierarchical state feedback control model of word production.


Assuntos
Eletrocorticografia/métodos , Epilepsia/fisiopatologia , Lateralidade Funcional/fisiologia , Ritmo Gama/fisiologia , Idioma , Córtex Pré-Frontal/fisiologia , Fala/fisiologia , Adulto , Humanos , Masculino
16.
Cancer Gene Ther ; 31(5): 687-697, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38347129

RESUMO

SMARCA4-deficient undifferentiated thoracic tumor is extremely invasive. This tumor with poor prognosis is easily confused with SMARCA4-deficent non-small cell lung cancer or sarcoma. Standard and efficient treatment has not been established. In this review, we summarized the etiology, pathogenesis and diagnosis, reviewed current and proposed innovative strategies for treatment and improving prognosis. Immunotherapy, targeting tumor microenvironment and epigenetic regulator have improved the prognosis of cancer patients. We summarized clinicopathological features and immunotherapy strategies and analyzed the progression-free survival (PFS) and overall survival (OS) of patients with SMARCA4-UT who received immune checkpoint inhibitors (ICIs). In addition, we proposed the feasibility of epigenetic regulation in the treatment of SMARCA4-UT. To our knowledge, this is the first review that aims to explore innovative strategies for targeting tumor microenvironment and epigenetic regulation and identify potential benefit population for immunotherapy to improve the prognosis.


Assuntos
DNA Helicases , Epigênese Genética , Imunoterapia , Neoplasias Torácicas , Fatores de Transcrição , Microambiente Tumoral , Humanos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Imunoterapia/métodos , DNA Helicases/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Neoplasias Torácicas/genética , Neoplasias Torácicas/terapia , Neoplasias Torácicas/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Prognóstico
17.
Ecology ; : e4375, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38924062

RESUMO

Fungi are key decomposers of deadwood, but the impact of anthropogenic changes in nutrients and temperature on fungal community and its consequences for wood microbial respiration are not well understood. Here, we examined how nitrogen and phosphorus additions (field experiment) and warming (laboratory experiment) together influence fungal composition and microbial respiration from decomposing wood of angiosperms and gymnosperms in a subtropical forest. Nutrient additions significantly increased wood microbial respiration via fungal composition, but effects varied with nutrient types and taxonomic groups. Specifically, phosphorus addition significantly increased wood microbial respiration (65%) through decreased acid phosphatase activity and increased abundance of fast-decaying fungi (e.g., white rot), while nitrogen addition marginally increased it (30%). Phosphorus addition caused a greater increase in microbial respiration in gymnosperms than in angiosperms (83.3% vs. 46.9%), which was associated with an increase in Basidiomycota:Ascomycota operational taxonomic unit abundance in gymnosperms but a decrease in angiosperms. The temperature dependencies of microbial respiration were remarkably constant across nutrient levels, consistent with metabolic scaling theory hypotheses. This is because there was no significant interaction between temperature and wood phosphorus availability or fungal composition, or the interaction among the three factors. Our results highlight the key role of tree identity in regulating nutrient response of wood microbial respiration through controlling fungal composition. Given that the range of angiosperm species may expand under climate warming and forest management, our data suggest that expansion will decrease nutrient effects on forest carbon cycling in forests previously dominated by gymnosperm species.

18.
Front Hum Neurosci ; 17: 1144159, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37275345

RESUMO

Trigeminal neuralgia (TN) is a severe and disabling facial pain condition and is characterized by intermittent, severe, electric shock-like pain in one (or more) trigeminal subdivisions. This pain can be triggered by an innocuous stimulus or can be spontaneous. Presently available therapies for TN include both surgical and pharmacological management; however, the lack of a known etiology for TN contributes to the unpredictable response to treatment and the variability in long-term clinical outcomes. Given this, a range of peripheral and central mechanisms underlying TN pain remain to be understood. We acquired functional magnetic resonance imaging (fMRI) data from TN patients who (1) rested comfortably in the scanner during a resting state session and (2) rated their pain levels in real time using a calibrated tracking ball-controlled scale in a pain tracking session. Following data acquisition, the data was analyzed using the conventional correlation analysis and two artificial intelligence (AI)-inspired deep learning methods: convolutional neural network (CNN) and graph convolutional neural network (GCNN). Each of the three methods yielded a set of brain regions related to the generation and perception of pain in TN. There were 6 regions that were identified by all three methods, including the superior temporal cortex, the insula, the fusiform, the precentral gyrus, the superior frontal gyrus, and the supramarginal gyrus. Additionally, 17 regions, including dorsal anterior cingulate cortex (dACC) and the thalamus, were identified by at least two of the three methods. Collectively, these 23 regions are taken to represent signature centers of TN pain and provide target areas for future studies seeking to understand the central mechanisms of TN.

19.
Sci Total Environ ; 878: 162972, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36958562

RESUMO

Soil microbes play key roles that support forest ecosystem functioning, while their community characteristics are strongly determined by tree species identity. However, the majority studies primarily focus on soil microorganisms in the topsoil, resulting in limited understanding of the linkages between tree species identity and the microbial communities that inhabit deep soils. Here we investigated the diversity, structure, function, and co-occurrence networks of soil bacterial and fungal communities, as well as related soil physicochemical properties, to a depth of two meters in dryland forests dominated by either Pinus tabuliformis, a native coniferous species, Robinia pseudoacacia, an exotic broadleaf and nitrogen-fixing species, or both. Tree species identity had stronger effects on soil multifunctionality and microbial community structure in the deep layers (80-200 cm) than in the top layers (0-60 cm). In addition, fungal communities were more responsive to tree species identity, whereas bacteria were more sensitive to soil depth. Tree species identity strongly influenced microbial network stability and complexity, with higher quantities in R. pseudoacacia than the other plantations, by affecting microbial composition and their associations. The increased in microbial network complexity and the relative abundance of keystone taxa enhance the soil multifunctionality of microbial productivity, sugar and chitin degradation, and nutrient availability and cycling. Meanwhile, the relative abundance of keystone taxa was more representative of soil multifunctionality than microbial diversity. Our study highlights that tree species identity significantly influences soil microbial community characteristics and multifunctionality, especially in deep soils, which will help us understand soil nutrients processed in plantation forest ecosystem and provide a reference for tree species selection in ecological restoration.


Assuntos
Ecossistema , Microbiota , Árvores , Solo/química , Microbiologia do Solo , Florestas , Bactérias
20.
Aging Dis ; 14(6): 2238-2248, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37199576

RESUMO

To study the long-term symptom burden among older COVID-19 survivors 2 years after hospital discharge and identify associated risk factors. The current cohort study included COVID-19 survivors aged 60 years and above, who were discharged between February 12 and April 10, 2020, from two designated hospitals in Wuhan, China. All patients were contacted via telephone and completed a standardized questionnaire assessing self-reported symptoms, the Checklist Individual Strength (CIS)-fatigue subscale, and two subscales of the Hospital Anxiety and Depression Scale (HADS). Of the 1,212 patients surveyed, the median (IQR) age was 68.0 (64.0-72.0), and 586 (48.3%) were male. At the two-year follow-up, 259 patients (21.4%) still reported at least one symptom. The most frequently self-reported symptoms were fatigue, anxiety, and dyspnea. Fatigue or myalgia, which was the most common symptom cluster (11.8%; 143/1212), often co-occurred with anxiety and chest symptoms. A total of 89 patients (7.7%) had CIS-fatigue scores ≥ 27, with older age (odds ratio [OR], 1.08; 95% CI: 1.05-1.11, P < 0.001) and oxygen therapy (OR, 2.19; 95% CI: 1.06-4.50, P= 0.03) being risk factors. A total of 43 patients (3.8%) had HADS-Anxiety scores ≥ 8, and 130 patients (11.5%) had HADS-Depression scores ≥ 8. For the 59 patients (5.2%) who had HADS total scores ≥ 16, older age, serious illness during hospitalization and coexisting cerebrovascular diseases were risk factors. Cooccurring fatigue, anxiety, and chest symptoms, as well as depression, were mainly responsible for long-term symptom burden among older COVID-19 survivors 2 years after discharge.

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