Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 50
Filtrar
1.
Proc Natl Acad Sci U S A ; 119(34): e2205920119, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35972963

RESUMO

Nuclear Ca2+ oscillations allow symbiosis signaling, facilitating plant recognition of beneficial microsymbionts, nitrogen-fixing rhizobia, and nutrient-capturing arbuscular mycorrhizal fungi. Two classes of channels, DMI1 and CNGC15, in a complex on the nuclear membrane, coordinate symbiotic Ca2+ oscillations. However, the mechanism of Ca2+ signature generation is unknown. Here, we demonstrate spontaneous activation of this channel complex, through gain-of-function mutations in DMI1, leading to spontaneous nuclear Ca2+ oscillations and spontaneous nodulation, in a CNGC15-dependent manner. The mutations destabilize a hydrogen-bond or salt-bridge network between two RCK domains, with the resultant structural changes, alongside DMI1 cation permeability, activating the channel complex. This channel complex was reconstituted in human HEK293T cell lines, with the resultant calcium influx enhanced by autoactivated DMI1 and CNGC15s. Our results demonstrate the mode of activation of this nuclear channel complex, show that DMI1 and CNGC15 are sufficient to create oscillatory Ca2+ signals, and provide insights into its native mode of induction.


Assuntos
Canais de Cálcio , Sinalização do Cálcio , Medicago truncatula , Proteínas de Plantas , Nodulação , Raízes de Plantas , Cálcio/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Sinalização do Cálcio/fisiologia , Núcleo Celular/metabolismo , Mutação com Ganho de Função , Regulação da Expressão Gênica de Plantas , Células HEK293 , Humanos , Medicago truncatula/genética , Medicago truncatula/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nodulação/genética , Nodulação/fisiologia , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Simbiose/fisiologia
2.
Mol Syst Biol ; 19(10): 1-23, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-38778223

RESUMO

RNA abundance is tightly regulated in eukaryotic cells by modulating the kinetic rates of RNA production, processing, and degradation. To date, little is known about time­dependent kinetic rates during dynamic processes. Here, we present SLAM­Drop­seq, a method that combines RNA metabolic labeling and alkylation of modified nucleotides in methanol­fixed cells with droplet­based sequencing to detect newly synthesized and preexisting mRNAs in single cells. As a first application, we sequenced 7280 HEK293 cells and calculated gene­specific kinetic rates during the cell cycle using the novel package Eskrate. Of the 377 robust­cycling genes that we identified, only a minor fraction is regulated solely by either dynamic transcription or degradation (6 and 4%, respectively). By contrast, the vast majority (89%) exhibit dynamically regulated transcription and degradation rates during the cell cycle. Our study thus shows that temporally regulated mRNA degradation is fundamental for the correct expression of a majority of cycling genes. SLAM­Drop­seq, combined with Eskrate, is a powerful approach to understanding the underlying mRNA kinetics of single­cell gene expression dynamics in continuous biological processes.


Assuntos
Ciclo Celular , RNA Mensageiro , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ciclo Celular/genética , Cinética , Análise de Sequência de RNA/métodos , Humanos
3.
Entropy (Basel) ; 25(7)2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37509982

RESUMO

Elevated mental workload (MWL) experienced by pilots can result in increased reaction times or incorrect actions, potentially compromising flight safety. This study aims to develop a functional system to assist administrators in identifying and detecting pilots' real-time MWL and evaluate its effectiveness using designed airfield traffic pattern tasks within a realistic flight simulator. The perceived MWL in various situations was assessed and labeled using NASA Task Load Index (NASA-TLX) scores. Physiological features were then extracted using a fast Fourier transformation with 2-s sliding time windows. Feature selection was conducted by comparing the results of the Kruskal-Wallis (K-W) test and Sequential Forward Floating Selection (SFFS). The results proved that the optimal input was all PSD features. Moreover, the study analyzed the effects of electroencephalography (EEG) features from distinct brain regions and PSD changes across different MWL levels to further assess the proposed system's performance. A 10-fold cross-validation was performed on six classifiers, and the optimal accuracy of 87.57% was attained using a multi-class K-Nearest Neighbor (KNN) classifier for classifying different MWL levels. The findings indicate that the wireless headset-based system is reliable and feasible. Consequently, numerous wireless EEG device-based systems can be developed for application in diverse real-driving scenarios. Additionally, the current system contributes to future research on actual flight conditions.

4.
Crit Rev Food Sci Nutr ; 62(32): 9053-9075, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34142875

RESUMO

Nonalcoholic fatty liver disease (NAFLD) has become a surge burden worldwide due to its high prevalence, with complicated deterioration symptoms such as liver fibrosis and cancer. No effective drugs are available for NALFD so far. The rapid growth of clinical demand has prompted the treatment of NAFLD to become a research hotspot. Protocatechuic acid (PCA) is a natural secondary metabolite commonly found in fruits, vegetables, grains, and herbal medicine. It is also the major internal metabolites of anthocyanins and other polyphenols. In the present manuscript, food sources, metabolic absorption, and efficacy of PCA were summarized while analyzing its role in improving NAFLD, as well as the mechanism involved. The results indicated that PCA could ameliorate NAFLD by regulating glucose and lipid metabolism, oxidative stress and inflammation, gut microbiota and metabolites. It was proposed for the first time that PCA might reduce NAFLD by enhancing the energy consumption of brown adipose tissue (BAT). However, the PCA administration mode and dose for NAFLD remain inconclusive. Fresh insights into the specific molecular mechanisms are required, while clinical trials are essential in the future. This review provides new targets and reasoning for the clinical application of PCA in the prevention and treatment of NAFLD.


Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Antocianinas/farmacologia , Hidroxibenzoatos/farmacologia , Hidroxibenzoatos/metabolismo , Fígado/metabolismo
5.
Financ Res Lett ; 47: 102726, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35185400

RESUMO

Taking the COVID-19 outbreak as the exogenous shock, we use quarterly reports of Chinese listed firms to examine whether enhanced environmental governance scheme improves corporate investment efficiency over the course of COVID-19. The results show that after the outbreak, firms with greater environmental governance scheme experience more efficient investments, with this effect being more pronounced in non-state-owned enterprises, firms unlisted as key pollution-monitoring units, and firms with higher financial constraints. The results are robust to a battery of robustness checks. These findings provide new evidence on the importance of environmental governance in reaping economic benefits and resilience during crisis times.

6.
J Asian Econ ; 75: 101320, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36567767

RESUMO

The COVID-19 outbreak had a significant impact on business cash flows and investment activities. This paper examined the COVID-19 impact on Chinese business investment in 3326 A-share listed quarterly financial reports, from which it was found that the negative relationship was more pronounced in the large, eastern Chinese state-owned firms. Using a propensity score matching method and difference-in-differences estimation, corporate financial flexibility was also examined, with the results indicating that high cash flexibility provided a buffer that allowed firms to better deal with adverse external shocks as the firms that had high cash flexibility were able to significantly increase their investments after the COVID-19 outbreak. Various robustness tests were conducted, all of which verified the robustness of the results. Overall, the empirical results provided evidence that the COVID-19 pandemic in China had a negative impact on Chinese listed firms, and verified the vital role of flexible financial reserves for firm survival and development during crises.

7.
Pharmacol Res ; 160: 105095, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32730904

RESUMO

Identification of risk factors for antibiotic treatment failure is urgently needed in acute exacerbations of chronic obstructive pulmonary disease (AECOPD). Here we investigated the relationship between sputum microbiome and clinical outcome of choice of initial antibiotics during hospitalization of AECOPD patients. Sputum samples of 41 AECOPD patients and 26 healthy controls were collected from Guangzhou Medical University, China. Samples were processed for 16S rRNA gene-based microbiome profiling. Thirty patients recovered with initial antibiotic treatment (antibiotic success or AS), while 11 patients showed poor outcome (antibiotic failure or AF). Substantial differences in microbiome were observed in AF versus AS patients and healthy controls. There was significantly decreased alpha diversity and increased relative abundances of Pseudomonas, Achromobacter, Stenotrophomonas and Ralstonia in AF patients. Conversely, Prevotella, Peptostreptococcus, Leptotrichia and Selenomonas were depleted. The prevalence of Selenomonas was markedly reduced in AF versus AS patients (9.1 % versus 60.0 %, P = 0.004). The AF patients with similar microbiome profiles in general responded well to the same new antibiotics in the adjusted therapy, indicating sputum microbiome may help guide the adjustment of antibiotics. Random forest analysis identified five microbiome operational taxonomic units together with C-reactive protein, procalcitonin and blood neutrophil count showing best predictability for antibiotic treatment outcome (area under curve 0.885). Functional inference revealed an enrichment of microbial genes in xenobiotic metabolism and antimicrobial resistance in AF patients, whereas genes in DNA repair and amino acid metabolism were depleted. Sputum microbiome may determine the clinical outcome of initial antibiotic treatment and be considered in the risk management of antibiotics in AECOPD.


Assuntos
Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Hospitalização , Pulmão/microbiologia , Microbiota , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Escarro/microbiologia , Idoso , Antibacterianos/efeitos adversos , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Pacientes Internados , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Projetos Piloto , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/microbiologia , Ribotipagem , Resultado do Tratamento
8.
J Am Soc Nephrol ; 29(8): 2060-2068, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29794128

RESUMO

Background Three different cell types constitute the glomerular filter: mesangial cells, endothelial cells, and podocytes. However, to what extent cellular heterogeneity exists within healthy glomerular cell populations remains unknown.Methods We used nanodroplet-based highly parallel transcriptional profiling to characterize the cellular content of purified wild-type mouse glomeruli.Results Unsupervised clustering of nearly 13,000 single-cell transcriptomes identified the three known glomerular cell types. We provide a comprehensive online atlas of gene expression in glomerular cells that can be queried and visualized using an interactive and freely available database. Novel marker genes for all glomerular cell types were identified and supported by immunohistochemistry images obtained from the Human Protein Atlas. Subclustering of endothelial cells revealed a subset of endothelium that expressed marker genes related to endothelial proliferation. By comparison, the podocyte population appeared more homogeneous but contained three smaller, previously unknown subpopulations.Conclusions Our study comprehensively characterized gene expression in individual glomerular cells and sets the stage for the dissection of glomerular function at the single-cell level in health and disease.


Assuntos
Células Endoteliais/metabolismo , Perfilação da Expressão Gênica , Glomérulos Renais/fisiologia , Células Mesangiais/metabolismo , Podócitos/metabolismo , Análise de Sequência de RNA , Animais , Células Cultivadas , Regulação da Expressão Gênica , Glomérulos Renais/citologia , Masculino , Camundongos , Camundongos Endogâmicos , Valores de Referência
9.
Nucleic Acids Res ; 44(6): 2514-27, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-26926107

RESUMO

Epithelial-to-mesenchymal transition (EMT) is a complex multistep process in which phenotype switches are mediated by a network of transcription factors (TFs). Systematic characterization of all dynamic TFs controlling EMT state transitions, especially for the intermediate partial-EMT state, represents a highly relevant yet largely unexplored task. Here, we performed a computational analysis that integrated time-course EMT transcriptomic data with public cistromic data and identified three synergistic master TFs (ETS2, HNF4A and JUNB) that regulate the transition through the partial-EMT state. Overexpression of these regulators predicted a poor clinical outcome, and their elimination readily abolished TGF-ß-induced EMT. Importantly, these factors utilized a clique motif, physically interact and their cumulative binding generally characterized EMT-associated genes. Furthermore, analyses of H3K27ac ChIP-seq data revealed that ETS2, HNF4A and JUNB are associated with super-enhancers and the administration of BRD4 inhibitor readily abolished TGF-ß-induced EMT. These findings have implications for systematic discovery of master EMT regulators and super-enhancers as novel targets for controlling metastasis.


Assuntos
Adenocarcinoma/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Fator 4 Nuclear de Hepatócito/genética , Neoplasias Pulmonares/genética , Proteína Proto-Oncogênica c-ets-2/genética , Fatores de Transcrição/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Antineoplásicos/farmacologia , Azepinas/farmacologia , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Perfilação da Expressão Gênica , Fator 4 Nuclear de Hepatócito/antagonistas & inibidores , Fator 4 Nuclear de Hepatócito/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fenótipo , Proteína Proto-Oncogênica c-ets-2/antagonistas & inibidores , Proteína Proto-Oncogênica c-ets-2/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Análise de Sequência de RNA , Transdução de Sinais , Proteína Smad3/genética , Proteína Smad3/metabolismo , Análise de Sobrevida , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Transcriptoma , Fator de Crescimento Transformador beta/farmacologia , Triazóis/farmacologia
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(12): 3811-6, 2016 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-30234942

RESUMO

Multilayer graphene, with wide absorption spectrum and unique photoelectric properties, is an ideal material to make the next generation of photoelectric detector. Taking graphene interband tunneling theory as the foundation, a photoelectric detector model with the structure of multilayer graphene nanoribbons was proposed. Nanoribbons which contacted with source and drain electrode at the end were sandwiched between the semiconductor substrate and the top and back gate. Using this model, a photoelectric conversion mechanism of multilayer graphene nanoribbon detector was established. It discussed the working principle of the detector at different top gate voltage, studied the relationship between the source-drain current and the incident light energy, researched the influence of the bias voltage, the length of depletion and the values of band gap on the dark current, and analyzed the change of detector responsibility and detectivity with the incident light energy under the different parameters. The results show that, the responsibility of detector increases with the layers of nanoribbons, and are affected by the band gap, the length of depletion and the bias voltage. The maximum responsibility up to 10(3) A·W(-1); By limiting on the top gate voltage, the band gap and other variables can control the dark current of system and increase the detectivity, the detectivity up to a maximum value of 10(9) cm Hz(1/2)·W(-1). The structure of multilayer graphene nanoribbons can enhance the absorption of the incident light, improve the sensitivity of the detector and the detection capability of weak light, and realize the detection from THz to far infrared wavelength of incident light. The detection performance is far better than that of many quantum structures and narrow-band semiconductor structure of photoelectric detector.

11.
Accid Anal Prev ; 195: 107382, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37979465

RESUMO

Regular speeders are those who commit speeding recidivism during a period. Among their speeding behaviors, some occurring in specific scenarios may cause more hazards to road users. Therefore, there is a need to evaluate the driving risks if the regular speeders have different speeding propensities. This study considers speeding-related hard-braking events (SHEs) as a safety surrogate measure and recognizes the regular speeders who encounter at least one SHEs during the study period as risky individuals. To identify speeding behaviors and hard-braking events from low-frequency GPS trajectories, we compare the average travel speed between pairwise adjacent GPS points to the posted speed limit and examine the speed curve and the corresponding travel distance between these GPS points, respectively. Thereafter, a logistic model, XGBoost, and three 1D Convolutional Neural Networks (CNNs) including AlexNet CNN, Mini-AlexNet CNN, and Simple CNN are respectively developed to recognize the regular speeders who encountered SHEs based on their speeding propensities. The proposed Mini-AlexNet CNN achieves a global F1-score of 91% and recall of 90% on the testing data, which are superior to other models. Further, the study uses the Shapley Additive exPlanation (SHAP) framework to visually interpret the contribution of speeding propensities on SHE likelihood. It is found that speeding by 50% or greater for no more than 285 m is the most dangerous kind among all the speeding behaviors. Speeding on roads without bicycle lanes or on roads with roadside parking and excessive accesses increases the probability of encountering SHEs. Based on the analyses, we put forward tailored recommendations that aim to restrict hazard-related speeding behaviors rather than speeding behaviors of all kinds.


Assuntos
Condução de Veículo , Humanos , Acidentes de Trânsito/prevenção & controle , Viagem , Modelos Logísticos , Comportamento Perigoso
12.
Microbiol Spectr ; 12(6): e0379123, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38747583

RESUMO

The upper and lower respiratory tract may share microbiome because they are directly continuous, and the nasal microbiome contributes partially to the composition of the lung microbiome. But little is known about the upper and lower airway microbiome of early postoperative lung transplant recipients (LTRs). Using 16S rRNA gene sequencing, we compared paired nasal swab (NS) and bronchoalveolar lavage fluid (BALF) microbiome from 17 early postoperative LTRs. The microbiome between the two compartments were significantly different in Shannon diversity and beta diversity. Four and eight core NS-associated and BALF-associated microbiome were identified, respectively. NS samples harbored more Corynebacterium, Acinetobacter, and Pseudomonas, while BALF contained more Ralstonia, Stenotrophomonas, Enterococcus, and Pedobacter. The within-subject dissimilarity was higher than the between-subject dissimilarity, indicating a greater impact of sampling sites than sampling individuals on microbial difference. There were both difference and homogeneity between NS and BALF microbiome in early postoperative LTRs. High levels of pathogens were detected in both samples, suggesting that both of them can reflect the diseases characteristics of transplanted lung. The differences between upper and lower airway microbiome mainly come from sampling sites instead of sampling individuals. IMPORTANCE: Lung transplantation is the only therapeutic option for patients with end-stage lung disease, but its outcome is much worse than other solid organ transplants. Little is known about the NS and BALF microbiome of early postoperative LTRs. Here, we compared paired samples of the nasal and lung microbiome from 17 early postoperative LTRs and showed both difference and homogeneity between the two samples. Most of the "core" microbiome in both NS and BALF samples were recognized respiratory pathogens, suggesting that both samples can reflect the diseases characteristics of transplanted lung. We also found that the differences between upper and lower airway microbiome in early postoperative LTRs mainly come from sampling sites instead of sampling individuals.


Assuntos
Bactérias , Líquido da Lavagem Broncoalveolar , Transplante de Pulmão , Microbiota , RNA Ribossômico 16S , Transplantados , Transplante de Pulmão/efeitos adversos , Humanos , Microbiota/genética , Líquido da Lavagem Broncoalveolar/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/genética , Adulto , Pulmão/microbiologia , Período Pós-Operatório , Idoso , Sistema Respiratório/microbiologia
13.
Microbiol Spectr ; 12(7): e0344123, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38864649

RESUMO

This study aimed to characterize the composition of intestinal and nasal microbiota in septic patients and identify potential microbial biomarkers for diagnosis. A total of 157 subjects, including 89 with sepsis, were enrolled from the affiliated hospital. Nasal swabs and fecal specimens were collected from septic and non-septic patients in the intensive care unit (ICU) and Department of Respiratory and Critical Care Medicine. DNA was extracted, and the V4 region of the 16S rRNA gene was amplified and sequenced using Illumina technology. Bioinformatics analysis, statistical processing, and machine learning techniques were employed to differentiate between septic and non-septic patients. The nasal microbiota of septic patients exhibited significantly lower community richness (P = 0.002) and distinct compositions (P = 0.001) compared to non-septic patients. Corynebacterium, Staphylococcus, Acinetobacter, and Pseudomonas were identified as enriched genera in the nasal microbiota of septic patients. The constructed machine learning model achieved an area under the curve (AUC) of 89.08, indicating its efficacy in differentiating septic and non-septic patients. Importantly, model validation demonstrated the effectiveness of the nasal microecological diagnosis prediction model with an AUC of 84.79, while the gut microecological diagnosis prediction model had poor predictive performance (AUC = 49.24). The nasal microbiota of ICU patients effectively distinguishes sepsis from non-septic cases and outperforms the gut microbiota. These findings have implications for the development of diagnostic strategies and advancements in critical care medicine.IMPORTANCEThe important clinical significance of this study is that it compared the intestinal and nasal microbiota of sepsis with non-sepsis patients and determined that the nasal microbiota is more effective than the intestinal microbiota in distinguishing patients with sepsis from those without sepsis, based on the difference in the lines of nasal specimens collected.


Assuntos
Bactérias , Biomarcadores , Fezes , Unidades de Terapia Intensiva , Microbiota , RNA Ribossômico 16S , Sepse , Humanos , Sepse/diagnóstico , Sepse/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , RNA Ribossômico 16S/genética , Biomarcadores/análise , Bactérias/isolamento & purificação , Bactérias/genética , Bactérias/classificação , Fezes/microbiologia , Adulto , Aprendizado de Máquina , Microbioma Gastrointestinal , Nariz/microbiologia , Corynebacterium/isolamento & purificação , Corynebacterium/genética , Acinetobacter/isolamento & purificação , Acinetobacter/genética , Idoso de 80 Anos ou mais , Staphylococcus/isolamento & purificação , Staphylococcus/genética , Pseudomonas/isolamento & purificação , Pseudomonas/genética
14.
Heliyon ; 10(4): e25186, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38384514

RESUMO

The relationship between gut microbiota and its metabolites with cardiovascular disease (CVD) has been proven. In this review, we aim to conclude the potential mechanism of gut microbiota and its metabolites on inducing the formation of vulnerable atherosclerotic plaque, and to discuss the effect of intestinal metabolites, including trimethylamine-N-oxide (TMAO), lipopolysaccharide (LPS), phenylacetylglutamine (PAG), short-chain fatty acids (SCFAs) on plaque stability. Finally, we include the impact of gut microbiota and its metabolites on plaque stability, to propose a new therapeutic direction for coronary heart disease. Gut microbiota regulation intervenes the progress of arteriosclerosis, especially on coronary atherosclerosis, by avoiding or reducing the formation of vulnerable plaque, to lower the morbidity rate of myocardial infarction.

15.
Curr Opin Plant Biol ; 76: 102478, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37857037

RESUMO

Root nodule development plays a vital role in establishing the mutualistic relationship between legumes and nitrogen-fixing rhizobia. Two primary processes are involved in nodule development: formative cell divisions in the root cortex and the subsequent differentiation of nodule cells. The first process involves the mitotic reactivation of differentiated root cortex cells to form nodule primordium after perceiving symbiotic signals. The second process enables the nascent nodule primordium cells to develop into various cell types, leading to the creation of a functional nodule capable of supporting nitrogen fixation. Thus, both division and differentiation of nodule cells are crucial for root nodule development. This review provides an overview of the most recent advancements in comprehending the cellular and molecular mechanisms underlying symbiotic nodule development in legumes.


Assuntos
Fabaceae , Rhizobium , Nódulos Radiculares de Plantas/metabolismo , Simbiose/fisiologia , Fabaceae/metabolismo , Fixação de Nitrogênio , Rhizobium/fisiologia
16.
Front Cell Infect Microbiol ; 13: 1038472, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37033478

RESUMO

Background: The imbalance of gut microbiota (GM) is associated with a higher risk of thrombosis in patients with atrial fibrillation (AF). Oral anticoagulants (OACs) have been found to significantly reduce the risk of thromboembolism and increase the risk of bleeding. However, the OAC-induced alterations in gut microbiota in patients with AF remain elusive. Methods: In this study, the microbial composition in 42 AF patients who received long-term OAC treatment (AF-OAC group), 47 AF patients who did not (AF group), and 40 volunteers with the risk of AF (control group) were analyzed by 16S rRNA gene sequencing of fecal bacterial DNA. The metagenomic functional prediction of major bacterial taxa was performed using the Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) software package. Results: The gut microbiota differed between the AF-OAC and AF groups. The abundance of Bifidobacterium and Lactobacillus decreased in the two disease groups at the genus level, but OACs treatment mitigated the decreasing tendency and increased beneficial bacterial genera, such as Megamonas. In addition, OACs reduced the abundance of pro-inflammatory taxa on the genus Ruminococcus but increased certain potential pathogenic taxa, such as genera Streptococcus, Escherichia-Shigella, and Klebsiella. The Subgroup Linear discriminant analysis effect size (LEfSe) analyses revealed that Bacteroidetes, Brucella, and Ochrobactrum were more abundant in the anticoagulated bleeding AF patients, Akkermansia and Faecalibacterium were more abundant in the non-anticoagulated-bleeding-AF patients. The neutrophil-to-lymphocyte ratio (NLR) was lower in the AF-OAC group compared with the AF group (P < 0.05). Ruminococcus was positively correlated with the NLR and negatively correlated with the CHA2DS2-VASc score (P < 0.05), and the OACs-enriched species (Megamonas and Actinobacteria) was positively correlated with the prothrombin time (PT) (P < 0.05). Ruminococcus and Roseburia were negatively associated with bleeding events (P < 0.05). Conclusions: Our study suggested that OACs might benefit AF patients by reducing the inflammatory response and modulating the composition and abundance of gut microbiota. In particular, OACs increased the abundance of some gut microbiota involved in bleeding and gastrointestinal dysfunction indicating that the exogenous supplementation with Faecalibacterium and Akkermansia might be a prophylactic strategy for AF-OAC patients to lower the risk of bleeding after anticoagulation.


Assuntos
Fibrilação Atrial , Microbioma Gastrointestinal , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/induzido quimicamente , Filogenia , RNA Ribossômico 16S/genética , Fatores de Risco , Anticoagulantes/uso terapêutico , Hemorragia/induzido quimicamente , Hemorragia/complicações , Administração Oral , Medição de Risco
17.
Clin Kidney J ; 16(11): 1965-1973, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37915931

RESUMO

Background: Chronic kidney disease (CKD) has emerged as a significant challenge to human health and economic stability in aging societies worldwide. Current clinical practice strategies remain insufficient for the early identification of kidney dysfunction, and the differential diagnosis of immunoglobulin A nephropathy (IgAN) predominantly relies on invasive kidney biopsy procedures. Methods: First, we assessed a case-control cohort to obtain urine samples from healthy controls and biopsy-confirmed CKD patients. Matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) was applied to detect urinary peptide and then these urinary peptide profiles were used to construct diagnostic models to distinguish CKD patients from controls and identify IgAN patients from other nephropathy patients. Furthermore, we assessed the robustness of the diagnostic models and their reproducibility by applying different algorithms. Results: A rapid and accurate working platform for detecting CKD and its IgAN subtype based on urinary peptide pattern detected by MALDI-TOF MS was established. Naturally occurring urinary peptide profiles were used to construct a diagnostic model to distinguish CKD patients from controls and identify IgAN patients from other nephropathy patients. The performance of several algorithms was assessed and demonstrated that the robustness of the diagnostic models as well as their reproducibility were satisfactory. Conclusions: The present findings suggest that the CKD-related and IgAN-specific urinary peptides discovered facilitate precise identification of CKD and its IgAN subtype, offering a dependable framework for screening conditions linked to renal dysfunction. This will aid in comprehending the pathogenesis of nephropathy and identifying potential protein targets for the clinical management of nephropathy.

18.
Heliyon ; 9(9): e19400, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37681153

RESUMO

Objectives: To evaluate a two-test strategy for HIV screening in the low-prevalence population and to assess the feasibility of utilizing the optimal signal-to-cutoff (S/CO) threshold on the chemiluminescence immunoassay(CMIA) and an additional rapid test on the gold immune-chromatography assay (GICA) for screening positive patients and optimization of clinical management. Methods: We conducted a retrospective study of samples analyzed by the fourth-generation Architect HIV Ag/Ab combo assay (CMIA) in a large medical center between June 2017 and August 2020. Reactive samples underwent a second screening test using the rapid test GICA, followed by Western blot (WB) as the confirmatory test. Receiver operating characteristic (ROC) curve analysis was used to determine the optimal S/CO. We calculated sensitivity, specificity, and predictive value based on our population. The performance of the single-test strategy (CMIA) was compared with that of the two-test strategy (CMIA and GICA). Logistic regression was used to analyze the factors of clinical characteristics leading to false positive results. Results: A total of 220558 samples were screened by CMIA, and 429 patients met the inclusion criteria. Of these, CMIA produced 199 false-positive results with a median S/CO of 1.93(IQR1.45-3.68) and 230 positive results with a median S/CO of 455.1 (IQR169.3-709.7). The optimal S/CO of the single-test strategy was 8.82, which achieved a sensitivity of 100% and a positive predictive value (PPV) of 90.9%. The two-test strategy (CMIA and GICA) provided a sensitivity of 100% and a PPV of 98.7%, which best correlated with the confirmatory test WB. The combination of S/CO 8.82 on the CMIA assay and additional test results of GICA can be defined as four types used to interpret HIV serostatus. The false positive rate (FPR) was high in the female, the age≤18 group, the pre-operative patients, and the patients from the clinical departments of Pediatrics, Gynecology and Obstetrics, and Oncology, etc. Conclusions: The false positive rate is high in the low-prevalence setting by using CMIA. The two-test strategy (CMIA and GICA) is recommended for HIV screening in hospitals. Hopefully, the clinicians will be able to interpret HIV serostatus and facilitate clinical decision-making while waiting for the confirmatory results.

19.
Nat Med ; 29(7): 1750-1759, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37349537

RESUMO

Exposure to environmental pollution influences respiratory health. The role of the airway microbial ecosystem underlying the interaction of exposure and respiratory health remains unclear. Here, through a province-wide chronic obstructive pulmonary disease surveillance program, we conducted a population-based survey of bacterial (n = 1,651) and fungal (n = 719) taxa and metagenomes (n = 1,128) from induced sputum of 1,651 household members in Guangdong, China. We found that cigarette smoking and higher PM2.5 concentration were associated with lung function impairment through the mediation of bacterial and fungal communities, respectively, and that exposure was associated with an enhanced inter-kingdom microbial interaction resembling the pattern seen in chronic obstructive pulmonary disease. Enrichment of Neisseria was associated with a 2.25-fold increased risk of high respiratory symptom burden, coupled with an elevation in Aspergillus, in association with occupational pollution. We developed an individualized microbiome-based health index, which covaried with exposure, respiratory symptoms and diseases, with potential generalizability to global datasets. Our results may inform environmental risk prevention and guide interventions that harness airway microbiome.


Assuntos
Microbiota , Doença Pulmonar Obstrutiva Crônica , Humanos , Sistema Respiratório , Doença Pulmonar Obstrutiva Crônica/etiologia , Doença Pulmonar Obstrutiva Crônica/microbiologia , Exposição Ambiental/efeitos adversos , Escarro/microbiologia
20.
Front Psychol ; 13: 794455, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35360612

RESUMO

Based on 2010 to 2019 Chinese outward foreign direct investment (OFDI) panel data from 39 host countries, this paper studies the relationships between host country cultural characteristics and Chinese OFDI. The OLS regression results show that the cultural tolerance and trust in the host countries are significantly positively correlated with Chinese OFDI, which are robust according to the system GMM tests. Further analysis reveals that cultural tolerance is more positively related to Chinese OFDI in host countries with higher legislation and economic freedom, while cultural trust is positively associated with Chinese OFDI in host countries with lower legislation and economic freedom. In addition, higher cultural tolerance and trust promote Chinese OFDI in countries with greater cultural distance. Unlike traditional studies based on cultural distance in international trade, using more representative cultural characteristics, this paper provides references to Chinese OFDI decision-making based on the root characteristics associated with heterogeneous cultural influences.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa