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1.
Cell ; 186(17): 3593-3605.e12, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37516107

RESUMO

Animal fertilization relies on hundreds of sperm racing toward the egg, whereas, in angiosperms, only two sperm cells are delivered by a pollen tube to the female gametes (egg cell and central cell) for double fertilization. However, unsuccessful fertilization under this one-pollen-tube design can be detrimental to seed production and plant survival. To mitigate this risk, unfertilized-gamete-controlled extra pollen tube entry has been evolved to bring more sperm cells and salvage fertilization. Despite its importance, the underlying molecular mechanism of this phenomenon remains unclear. In this study, we report that, in Arabidopsis, the central cell secretes peptides SALVAGER1 and SALVAGER2 in a directional manner to attract pollen tubes when the synergid-dependent attraction fails or is terminated by pollen tubes carrying infertile sperm cells. Moreover, loss of SALs impairs the fertilization recovery capacity of the ovules. Therefore, this research uncovers a female gamete-attraction system that salvages seed production for reproductive assurance.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Animais , Arabidopsis/fisiologia , Fertilização , Tubo Polínico , Sementes , Células Germinativas Vegetais
2.
Cell ; 146(1): 80-91, 2011 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-21729781

RESUMO

Proper eukaryotic DNA replication requires temporal separation of helicase loading from helicase activation and replisome assembly. Using an in vitro assay for eukaryotic origin-dependent replication initiation, we investigated the control of these events. After helicase loading, we found that the Dbf4-dependent Cdc7 kinase (DDK) but not S phase cyclin-dependent kinase (S-CDK) is required for the initial origin recruitment of Sld3 and the Cdc45 helicase-activating protein. Likewise, in vivo, DDK drives early-firing-origin recruitment of Cdc45 before activation of S-CDK. After S-CDK activation, a second helicase-activating protein (GINS) and the remainder of the replisome are recruited to the origin. Finally, recruitment of lagging but not leading strand DNA polymerases depends on Mcm10 and DNA unwinding. Our studies identify distinct roles for DDK and S-CDK during helicase activation and support a model in which the leading strand DNA polymerase is recruited prior to origin DNA unwinding and RNA primer synthesis.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Replicação do DNA , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , DNA Polimerase I/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fase G1 , Proteínas Nucleares/metabolismo , Origem de Replicação , Fase S , Saccharomyces cerevisiae/citologia
3.
Hepatology ; 79(2): 425-437, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37611260

RESUMO

BACKGROUND AND AIMS: The predominantly progressive, indeterminate, and predominantly regressive (P-I-R) classification extends beyond staging and provides information on dynamic changes of liver fibrosis. However, the prognostic implication of P-I-R classification is not elucidated. Therefore, in the present research, we investigated the utility of P-I-R classification in predicting the on-treatment clinical outcomes. APPROACH AND RESULTS: In an extension study on a randomized controlled trial, we originally enrolled 1000 patients with chronic hepatitis B and biopsy-proven histological significant fibrosis, and treated them for more than 7 years with entecavir-based therapy. Among the 727 patients with a second biopsy at treatment week 72, we compared P-I-R classification and Ishak score changes in 646 patients with adequate liver sections for the histological evaluation. Progressive, indeterminate, and regressive cases were observed in 70%, 17%, and 13% of patients before treatments and 20%, 14%, and 64% after 72-week treatment, respectively, which could further differentiate the histological outcomes of patients with stable Ishak scores. The 7-year cumulative incidence of HCC was 1.5% for the regressive cases, 4.3% for the indeterminate cases, and 22.8% for the progressive cases ( p <0.001). After adjusting for age, treatment regimen, platelet counts, cirrhosis, Ishak fibrosis score changes, and Laennec staging, the posttreatment progressive had a HR of 17.77 (vs. posttreatment regressive; 95% CI: 5.55-56.88) for the incidence of liver-related events (decompensation, HCC, and death/liver transplantation). CONCLUSIONS: The P-I-R classification can be a meaningful complement to the Ishak fibrosis score not only in evaluating the histological changes but also in predicting the clinical outcomes.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Antivirais/uso terapêutico , Neoplasias Hepáticas/patologia , Cirrose Hepática/patologia , Fígado/patologia , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/patologia , Fibrose , Biópsia/efeitos adversos
4.
Clin Gastroenterol Hepatol ; 22(3): 591-601.e3, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38040276

RESUMO

BACKGROUND & AIMS: Liver fibrosis in patients with chronic hepatitis B can regress with successful antiviral therapy. However, the long-term clinical benefits of fibrosis regression have not been fully elucidated. This study investigated the association between biopsy-proven fibrosis regression by predominantly progressive, indeterminate, and predominantly regressive (P-I-R) score and liver-related events (LREs) in chronic hepatitis B patients. METHODS: Patients with on-treatment liver biopsy and significant fibrosis/cirrhosis (Ishak stage ≥3) were included in this analysis. Fibrosis regression was evaluated according to the P-I-R score of the Beijing Classification. LREs were defined as decompensations, hepatocellular carcinoma, liver transplantation, or death. The Cox proportional hazards model was used to determine associations of fibrosis regression with LREs. RESULTS: A total of 733 patients with Ishak stages 3/4 (n = 456; 62.2%) and cirrhosis (Ishak stages 5/6; n = 277; 37.8%) by on-treatment liver biopsy were enrolled. According to the P-I-R score, fibrosis regression, indeterminate, and progression were observed in 314 (42.8%), 230 (31.4%), and 189 (25.8%) patients, respectively. The 7-year cumulative incidence of LREs was 4.1%, 8.7%, and 18.1% in regression, indeterminate, and progression, respectively (log-rank, P < .001). Compared with patients with fibrosis progression, those with fibrosis regression had a lower risk of LREs (adjusted hazard ratio, 0.40; 95% CI, 0.16-0.99; P = .047), followed by the indeterminate group (adjusted hazard ratio, 0.86; 95% CI, 0.40-1.85; P = .691). Notably, this favorable association also was observed in patients with cirrhosis or low platelet counts (<150 × 109/L). CONCLUSIONS: Antiviral therapy-induced liver fibrosis regression assessed by P-I-R score is associated with reduced LREs. This shows the utility of histologic fibrosis regression assessed by on-treatment P-I-R score as a surrogate endpoint for clinical events in patients with hepatitis B virus-related fibrosis or early cirrhosis.


Assuntos
Hepatite B Crônica , Hepatite B , Neoplasias Hepáticas , Humanos , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/patologia , Fígado/patologia , Cirrose Hepática/complicações , Hepatite B/complicações , Neoplasias Hepáticas/patologia , Antivirais/uso terapêutico , Biópsia
5.
Am J Gastroenterol ; 119(4): 700-711, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37929952

RESUMO

INTRODUCTION: Portal hypertension progression can be relieved after controlling the etiology of liver cirrhosis. Whether beta-blockers could additionally enhance the effects during treatment, particularly for small esophageal varices (EV), was unclear. This study aims to assess the efficacy of add-on carvedilol to delay EV progression during anti-hepatitis B virus (HBV) treatment in HBV-related cirrhosis. METHODS: This randomized controlled trial enrolled patients with virologically suppressed HBV-compensated cirrhosis and small/medium EV. The participants were randomly assigned to receive nucleos(t)ide analog (NUC) or carvedilol 12.5 mg plus NUC (1:1 allocation ratio). The primary end point was the progression rate of EV at 2 years of follow-up. RESULTS: A total of 238 patients (small EV, 77.3%) were randomized into 119 NUC and 119 carvedilol plus NUC (carvedilol [CARV] combination group). Among them, 205 patients (86.1%) completed paired endoscopies. EV progression rate was 15.5% (16/103) in the NUC group and 12.7% (13/102) in the CARV combination group (relative risk = 0.79, 95% confidence interval 0.36-1.75, P = 0.567). Subgroup analysis on medium EV showed the CARV combination group had a more favorable effect in promoting EV regression (43.5% vs 13.1%, P = 0.022) than NUC alone, but not in small cases ( P = 0.534). The incidence of liver-related events (decompensation, hepatocellular carcinoma, or death/liver transplantation) within 2 years was similar between the 2 groups (11.2% vs 10.4%, P = 0.881). DISCUSSION: The overall results did not show statistically significant differences between the added carvedilol strategy and NUC monotherapy in preventing EV progression in patients with virologically suppressed HBV-compensated cirrhosis. However, the carvedilol-added approach might offer improved outcomes specifically for patients with medium EV (NCT03736265).


Assuntos
Vírus da Hepatite B , Neoplasias Hepáticas , Humanos , Carvedilol/uso terapêutico , Antivirais/uso terapêutico , Cirrose Hepática/tratamento farmacológico
6.
Plant Biotechnol J ; 22(9): 2410-2423, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38634166

RESUMO

The N6-methyladenosine (m6A) mRNA modification is crucial for plant development and stress responses. In rice, the male sterility resulting from the deficiency of OsFIP37, a core component of m6A methyltransferase complex, emphasizes the significant role of m6A in male fertility. m6A is reversible and can be removed by m6A demethylases. However, whether mRNA m6A demethylase regulates male fertility in rice has remained unknown. Here, we identify the mRNA m6A demethylase OsALKBH9 and demonstrate its involvement in male fertility regulation. Knockout of OsALKBH9 causes male sterility, dependent on its m6A demethylation activity. Cytological analysis reveals defective tapetal programmed cell death (PCD) and excessive accumulation of microspores exine in Osalkbh9-1. Transcriptome analysis of anthers shows up-regulation of genes involved in tapetum development, sporopollenin synthesis, and transport pathways in Osalkbh9-1. Additionally, we demonstrate that OsALKBH9 demethylates the m6A modification in TDR and GAMYB transcripts, which affects the stability of these mRNAs and ultimately leads to excessive accumulation of pollen exine. Our findings highlight the precise control of mRNA m6A modification and reveal the pivotal roles played by OsALKBH9-mediated m6A demethylation in tapetal PCD and pollen exine accumulation in rice.


Assuntos
Desmetilação , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Pólen , Oryza/genética , Oryza/metabolismo , Pólen/genética , Pólen/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Adenosina/análogos & derivados , Adenosina/metabolismo , Apoptose/genética , Infertilidade das Plantas/genética
7.
New Phytol ; 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39188077

RESUMO

Aberrant RNA modifications can lead to dysregulated gene expression and impeded growth in plants. Ribosomal RNA (rRNA) constitutes a substantial portion of total RNA, while the precise functions and molecular mechanisms underlying rRNA modifications in plants remain largely elusive. Here, we elucidated the exclusive occurrence of the canonical RNA modification N6-methyladenosine (m6A) solely 18S rRNA, but not 25S rRNA. We identified a completely uncharacterized protein, ATMETTL5, as an Arabidopsis m6A methyltransferase responsible for installing m6A methylation at the 1771 site of the 18S rRNA. ATMETTL5 is ubiquitously expressed and localized in both nucleus and cytoplasm, mediating rRNA m6A methylation. Mechanistically, the loss of ATMETTL5-mediated methylation results in attenuated translation. Furthermore, we uncovered the role of ATMETTL5-mediated methylation in coordinating blue light-mediated hypocotyl growth by regulating the translation of blue light-related messenger RNAs (mRNAs), specifically HYH and PRR9. Our findings provide mechanistic insights into how rRNA modification regulates ribosome function in mRNA translation and the response to blue light, thereby advancing our understanding of the role of epigenetic modifications in precisely regulating mRNA translation in plants.

8.
Hepatology ; 78(4): 1118-1132, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37098756

RESUMO

BACKGROUND AIMS: Excessive deposition and crosslinking of extracellular matrix increases liver density and stiffness, promotes fibrogenesis, and increases resistance to fibrinolysis. An emerging therapeutic opportunity in liver fibrosis is to target the composition of the extracellular matrix or block pathogenic communication with surrounding cells. However, the type and extent of extracellular changes triggering liver fibrosis depend on the underlying etiology. Our aim was to unveil matrisome genes not dependent on etiology, which are clinically relevant to liver fibrosis. APPROACH RESULTS: We used transcriptomic profiles from liver fibrosis cases of different etiologies to identify and validate liver fibrosis-specific matrisome genes (LFMGs) and their clinical and biological relevance. Dysregulation patterns and cellular landscapes of LFMGs were further explored in mouse models of liver fibrosis progression and regression by bulk and single-cell RNA sequencing. We identified 35 LFMGs, independent of etiology, representing an LFMG signature defining liver fibrosis. Expression of the LFMG signature depended on histological severity and was reduced in regressive livers. Patients with liver fibrosis, even with identical pathological scores, could be subclassified into LFMG Low and LFMG High , with distinguishable clinical, cellular, and molecular features. Single-cell RNA sequencing revealed that microfibrillar-associated protein 4 + activated HSC increased in LFMG High patients and were primarily responsible for the LFMG signature expression and dysregulation. CONCLUSIONS: The microfibrillar-associated protein 4 + -activated HSC-derived LFMG signature classifies patients with liver fibrosis with distinct clinical and biological characteristics. Our findings unveil hidden information from liver biopsies undetectable using traditional histologic assessments.


Assuntos
Matriz Extracelular , Cirrose Hepática , Camundongos , Animais , Humanos , Cirrose Hepática/patologia , Matriz Extracelular/metabolismo , Fígado/patologia , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Modelos Animais de Doenças , Células Estreladas do Fígado/metabolismo
9.
J Med Virol ; 96(6): e29606, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38818708

RESUMO

Hepatitis B virus (HBV) integration exists throughout the clinical course of chronic hepatitis B (CHB). This study investigated the effects of long-term antiviral therapy on the level and profiles of transcriptionally active HBV integration. Serial liver biopsies and paired blood samples were obtained from 16, 16, and 22 patients with CHB at baseline, 78, and 260 weeks of entecavir monotherapy or combined with pegylated interferon alfa, respectively. Serum HBV biomarkers were longitudinally assessed. RNA-seq and HIVID2 program was used to identify HBV-host chimeric RNAs transcribed from integrated DNA. The counts of HBV integration reads were positively related to both serum HBV DNA levels (r = 0.695, p = 0.004) and HBeAg titers (r = 0.724, p = 0.021) at baseline, but the positive correlation exited only to the serum HBsAg levels after 260 weeks of antiviral therapy (r = 0.662, p = 0.001). After 78 weeks of antiviral therapy, the levels of HBV integration expression decreased by 12.25 folds from baseline. The viral junction points were enriched at the S and HBx genes after the long-term antiviral therapy. HBs-FN1 became one of the main transcripts, with the mean proportion of HBs-FN1 in all integrated expression increased from 2.79% at baseline to 10.54% at Week 260 of antiviral treatment. Antiviral therapy may reduce but not eliminate the HBV integration events and integration expression. Certain integration events, such as HBs-FN1 can persist in long-term antiviral treatment.


Assuntos
Antivirais , DNA Viral , Vírus da Hepatite B , Hepatite B Crônica , Fígado , Integração Viral , Humanos , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Antivirais/uso terapêutico , Masculino , Vírus da Hepatite B/genética , Vírus da Hepatite B/efeitos dos fármacos , Adulto , Feminino , Fígado/virologia , Pessoa de Meia-Idade , DNA Viral/sangue , DNA Viral/genética , Guanina/análogos & derivados , Guanina/uso terapêutico , Interferon-alfa/uso terapêutico , Antígenos E da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Estudos Longitudinais
10.
Stat Med ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145573

RESUMO

Joint models for longitudinal and time-to-event data are receiving increasing attention owing to its capability of capturing the possible association between these two types of data. Typically, a joint model consists of a longitudinal submodel for longitudinal processes and a survival submodel for the time-to-event response, and links two submodels by common covariates that may carry both fixed and random effects. However, research gaps still remain on how to simultaneously select fixed and random effects from the two submodels under the joint modeling framework efficiently and effectively. In this article, we propose a novel block-coordinate gradient descent (BCGD) algorithm to simultaneously select multiple longitudinal covariates that may carry fixed and random effects in the joint model. Specifically, for the multiple longitudinal processes, a linear mixed effect model is adopted where random intercepts and slopes serve as essential covariates of the trajectories, and for the survival submodel, the popular proportional hazard model is employed. A penalized likelihood estimation is used to control the dimensionality of covariates in the joint model and estimate the unknown parameters, especially when estimating the covariance matrix of random effects. The proposed BCGD method can successfully capture the useful covariates of both fixed and random effects with excellent selection power, and efficiently provide a relatively accurate estimate of fixed and random effects empirically. The simulation results show excellent performance of the proposed method and support its effectiveness. The proposed BCGD method is further applied on two real data sets, and we examine the risk factors for the effects of different heart valves, differing on type of tissue, implanted in the aortic position and the risk factors for the diagnosis of primary biliary cholangitis.

11.
Biogerontology ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582786

RESUMO

Aging entails the progressive decline in the body's self-regulation and functionality over time. Notably, obesity and aging exhibit parallel phenotypes, with obesity further accelerating the aging process across multiple dimensions and diminishing lifespan. In this study, we explored the impact of trans fatty acid (TFA) consumption on the overall health and lifespan of male Drosophila melanogaster under an isocaloric high-sugar and high-fat diet. Our results indicate that TFA intake results in a shortened lifespan, elevated body weight, and increased triglyceride levels in flies fed a high-sugar and high-fat diet with equivalent caloric intake. Additionally, TFA exposure induces oxidative stress, locomotor deficits, and damage to the intestinal barrier in flies. Collectively, chronic TFA consumption expedites the aging process and reduces the lifespan of male Drosophila melanogaster. These results contribute supplementary evidence regarding the adverse health effects associated with TFAs.

12.
Rapid Commun Mass Spectrom ; 38(6): e9703, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38356091

RESUMO

RATIONALE: Secondary hypertension is often caused by activation of complex multi-organ endocrine systems, while renin activity indicated by angiotensins (Angs), aldosterone (ALD) and cortisol (COR) in such systems are generally accepted as its diagnostic markers. As antibody-based methods cannot offer comparable quantification for these biomarkers, a liquid chromatography (LC)-tandem mass spectrometry (MS/MS)-based approach was developed to quantify them simultaneously and accurately. METHODS: Five different beads for magnetic solid-phase extraction (MSPE) were evaluated towards their enrichment efficiency for these biomarkers. An LC system with optimized elution gradient and a triple-quadrupole MS with tuned parameters were coupled to quantitatively monitor the extracted analytes. The method performance was further examined such as linearity, precision, stability, recovery rate and matrix effect. Based on the developed method, the abundance of Ang II, ALD and COR in plasma was measured and the quantification was compared with that derived from commercial ELISA kits. RESULTS: As compared with other MSPEs, Angs, ALD and COR were highly enriched by the HLB magnetic beads with satisfactory recoveries. These analytes were simultaneously quantified by LC/MS/MS and all the method parameters for quantification were well matched with the requirements of clinical testing. Comparison of the quantitative results derived from ELISA and LC/MS/MS exhibited that the two methods offered basically comparable values with Pearson r values at 0.896, 0.895 and 0.835, respectively. The stability test for plasma Angs at room temperature indicated that the abundance of Ang II was relatively stable within 3 h, whereas that of Ang I and Ang 1-7 was time-dependently changed. CONCLUSIONS: Coupling of HLB beads and LC/MS/MS thus enables simultaneous quantification of a set of biomarkers related to secondary hypertension.


Assuntos
Hipertensão , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes , Cromatografia Líquida/métodos , Extração em Fase Sólida/métodos , Biomarcadores , Fenômenos Magnéticos , Cromatografia Líquida de Alta Pressão
13.
Ther Drug Monit ; 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39240829

RESUMO

BACKGROUND: Pyrazinamide is used to treat drug-susceptible (DS) and multidrug-resistant (MDR) tuberculosis (TB). This study aimed to characterize the factors associated with the pharmacokinetic parameters of pyrazinamide and evaluate the disposition of the current regimen, which could provide suggestions for adequate dosing strategies for therapeutic targets. METHODS: A population pharmacokinetic model of pyrazinamide was developed based on the data from 499 plasma concentrations from 222 Chinese patients diagnosed with DS or MDR TB. Pyrazinamide exposure was best described using a one-compartment model. RESULTS: No significant differences were observed in the pharmacokinetic parameters between DS and MDR TB. The final covariate model showed that total body weight was the only significant covariate for apparent clearance, which increased by 0.45 L/h with a 10 kg increase in body weight. A simulation showed that for typical subjects weighing 40-80 kg, a fixed dosage of 1500 mg daily had an area under the concentration-time curve from 0 to 24 hours (AUC0-24) of 389.9-716.0 mg·h/L and peak serum concentrations of the drug (Cmax) of 32.2-44.8 mg/L. CONCLUSIONS: Fixed pyrazinamide doses of 1500, 1750, and 2000 mg are recommended for patients weighing 40-70, 70-80, and 80-90 kg, respectively, to achieve the exposure targets of AUC0-24 > 363 mg·h/L or Cmax > 35 mg/L to attain efficacy.

14.
Conserv Biol ; 38(4): e14264, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38563105

RESUMO

Antarctica terrestrial ecosystems are facing the most threats from global climate change, which is altering plant composition greatly. These transformations may cause major reshuffling of soil community composition, including functional traits and diversity, and therefore affect ecosystem processes in Antarctica. We used high-throughput sequencing analysis to investigate soil nematodes under 3 dominant plant functional groups (lichens, mosses, and vascular plants) and bare ground in the Antarctic region. We calculated functional diversity of nematodes based on their diet, life histories, and body mass with kernel density n-dimensional hypervolumes. We also calculated taxonomic and functional beta diversity of the nematode communities based on Jaccard dissimilarity. The presence of plants had no significant effect on the taxonomic richness of nematodes but significantly increased nematode functional richness. The presence of plants also significantly decreased taxonomic beta diversity (homogenization). Only mosses and vascular plants decreased nematode functional beta diversity, which was mostly due to a decreased effect of the richness difference component. The presence of plants also increased the effect of deterministic processes potentially because environmental filtering created conditions favorable to nematodes at low trophic levels with short life histories and small body size. Increasing plant cover in the Antarctic due to climate change may lead to increased diversity of nematode species that can use the scarce resources and nematode taxonomic and functional homogenization. In a future under climate change, community restructuring in the region is possible.


Efectos de la posición taxonómica de las plantas sobre las comunidades de nemátodos del suelo en la Antártida Resumen Los ecosistemas terrestres de la Antártida enfrentan las mayores amenazas del cambio climático global, que está alterando gravemente la composición de plantas. Estas transformaciones pueden provocar una reorganización importante de la composición de la comunidad del suelo, incluyendo atributos y diversidad funcionales, y por lo tanto afectar los procesos ecosistémicos en la Antártida. Utilizamos análisis de secuenciación de alto rendimiento para investigar nemátodos del suelo debajo de tres grupos funcionales de plantas dominantes (líquenes, musgos y plantas vasculares) y de suelo desnudo en la región de la Antártida. Calculamos la diversidad funcional de nemátodos con base en su dieta, historia de vida y masa corporal mediante hipervolúmenes n­dimensionales de densidad del núcleo. También calculamos la diversidad beta taxonómica y funcional de las comunidades de nemátodos con base en la disimilitud de Jacard. La presencia de plantas no tuvo efecto significativo sobre la riqueza taxonómica de nemátodos, pero incrementó su riqueza funcional significativamente. La presencia de plantas también disminuyó la diversidad beta taxonómica (homogenización) significativamente. Solo musgos y plantas vasculares disminuyeron la diversidad beta funcional de nemátodos, lo cual se debió principalmente a un menor efecto del componente de diferencia de riqueza. La presencia de plantas también incrementó el efecto de los procesos determinísticos posiblemente porque el filtrado ambiental creó condiciones favorables para los nemátodos de niveles tróficos inferiores con historias de vida corta y tamaño corporal pequeño. El incremento de la cobertura de plantas en la Antártida debido al cambio climático puede conducir a una mayor diversidad de especies de nemátodos que pueden utilizar los escasos recursos y a la homogenización taxonómica y funcional de los nemátodos. En un futuro bajo el cambio climático, es posible la reestructuración comunitaria en la región.


Assuntos
Biodiversidade , Nematoides , Plantas , Solo , Animais , Regiões Antárticas , Nematoides/fisiologia , Plantas/classificação
15.
Environ Res ; 261: 119725, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39096988

RESUMO

Microbial electrolysis cell-assisted anaerobic digestion represents a promising approach for enhancing methanogenesis. This study investigated the impact of varying energy levels followed by long-term open circuit on biogas recovery from food waste. The results demonstrated that a mild voltage of 0.4 V resulted in 61.7% increase in methane yield, with a methane composition reaching 78.89% vol and a remarkable reduction in digestion time by 8 days. Additionally, the facilitated effects remained after prolonged periods of open-circuit. In-depth study revealed that energization significantly enhanced organic hydrolysis, redox proteins secretion and sludge electro-activity. Microbial communities showed that the ever-present energization enriched the hydrolytic bacterium and electrophiles. Subsequent investigations also revealed the upgradation of enzyme-encoding genes associated with hydrolysis and the synthesis of flavin and its homologs (i.e. ribE, ssuE and nfrA2). These findings collectively demonstrated the enduring benefits of energization were linked to the enhanced hydrolysis and regulated mediator-mediated electron transfer pathway.


Assuntos
Metano , Metano/metabolismo , Anaerobiose , Biocombustíveis , Eletrólise , Esgotos/microbiologia , Esgotos/química , Reatores Biológicos , Perda e Desperdício de Alimentos
16.
Ergonomics ; : 1-14, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613399

RESUMO

Emotion is an important factor that can lead to the occurrence of aggressive driving. This paper proposes an association rule mining-based method for analysing contributing factors associated with aggressive driving behaviour among online car-hailing drivers. We collected drivers' emotion data in real time in a natural driving setting. The findings show that 29 of the top 50 association rules for aggressive driving are related to emotions, revealing a strong relationship between driver emotions and aggressive driving behaviour. The emotions of anger, surprised, happy and disgusted are frequently associated with aggressive driving behaviour. Negative emotions combined with other factors (for example, driving at high speeds and high acceleration rates and with no passengers in the vehicle) are more likely to lead to aggressive driving behaviour than negative emotions alone. The results of this study provide practical implications for the supervision and training of car-hailing drivers.


Based on the association rule mining method, we found a close connection between drivers' emotional states and the manifestation of aggressive driving behaviours. The findings indicate that the combination of negative emotions and various contributing factors significantly amplifies the likelihood of aggressive driving.

17.
J Ment Health ; : 1-11, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654552

RESUMO

BACKGROUND: Positive psychological interventions (PPIs) are known to be effective in alleviating depression. However, the effect of PPIs on positive and negative emotions in depressed participants is not unclear. AIMS: To systematically investigate the effects of PPIs on positive and negative emotions in depressed individuals. METHODS: 6 databases were searched for randomized controlled trials of PPIs in individuals with depressive disorders or depressive symptoms. Hedges' g value was computed using a random-effects model to determine effect sizes. RESULTS: 14 trials from 13 studies were included. Our meta-analysis showed that PPIs had significant but small effects on improving positive affect (g = 0.33, p = .02), life satisfaction (g = 0.26, p = .03), happiness (g = 0.62, p = .03) and depression (g = -0.32, p = .001), and negligible effects on improving well-being (g = 0.13, p = .24) and negative affect (g = -0.15, p = .31). Subgroup analyses of depression showed that PPIs have experienced benefits in improving depression in most subgroups. In addition, none of the subgroup analyses performed for outcomes other than depression found PPIs to be more effective than controls. CONCLUSION: PPIs can improve positive affect, life satisfaction, happiness and depression in depressed individuals, but further studies are needed to validate their effects on well-being, and negative affect.

18.
Appl Environ Microbiol ; 89(10): e0095623, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37815340

RESUMO

Klebsiella pneumoniae is a ubiquitous human pathogen, and its clinical treatment faces two major challenges: multidrug resistance and the pathogenesis of hypervirulent K. pneumoniae. The discovery and study of conditionally essential (CE) genes that can function as potential antimicrobial targets has always been a research concern due to their restriction in the development of novel antibiotics. However, the lack of essential functional genomic data has hampered the study of the mechanisms of essential genes related to antimicrobial susceptibility. In this study, we developed a pooled CE genes mobile clustered regularly interspaced short palindromic repeat (CRISPR) interference screening method (Mobile-CRISPRi-seq) for K. pneumoniae to identify genes that play critical roles in antimicrobial fitness in vitro and host immunity in vivo. Targeting 870 predicted CE genes in K. pneumoniae, Mobile-CRISPRi-seq uncovered the depletion of tetrahydrofolate synthesis pathway genes folB and folP under trimethoprim pressure. Our screening also identified genes waaE and fldA related to polymyxin and ß-lactam susceptibility by applying a screening strategy based on Mobile-CRISPRi-seq and comparative genomics. Furthermore, using a mouse infection model and Mobile-CRISPRi-seq, multiple virulence genes were identified, and among these genes, pal, yciS, and ribB were demonstrated to contribute to the pathogenesis of K. pneumoniae. This study provides a simple, rapid, and effective platform for screening potential antimicrobial targets and virulence genes in K. pneumoniae, and this broadly applicable system can be expanded for high-throughput functional gene study in multiple pathogenic bacteria, especially in gram-negative bacteria. IMPORTANCE The discovery and investigation of conditionally essential (CE) genes that can function as potential antimicrobial targets has always been a research concern because of the restriction of antimicrobial targets in the development of novel antibiotics. In this study, we developed a pooled CE gene-wide mobile clustered regularly interspaced short palindromic repeat (CRISPR) interference sequencing (Mobile-CRISPRi-seq) strategy in Klebsiella pneumoniae to identify genes that play critical roles in the fitness of antimicrobials in vitro and host immunity in vivo. The data suggest a robust tool to screen for loss-of-function phenotypes in a pooled gene knockdown library in K. pneumoniae, and Mobile-CRISPRi-seq may be expanded to multiple bacteria for screening and identification of genes with crucial roles in the fitness of antimicrobials and hosts.


Assuntos
Genes Essenciais , Klebsiella pneumoniae , Humanos , Klebsiella pneumoniae/genética , Virulência/genética , Técnicas de Silenciamento de Genes , Bactérias/genética , Antibacterianos/farmacologia
19.
J Med Virol ; 95(10): e29156, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37822064

RESUMO

Despite the increasing prevalence of steatosis in patients with chronic hepatitis B (CHB), whether the changes in steatosis impact fibrosis regression during antiviral therapy remain unclear. We aimed to identify the association between histological changes of steatosis and fibrosis in patients undergone antiviral treatment. Patients with paired liver biopsies before and after 78 weeks of antiviral therapy were enrolled in this study. Liver fibrosis was assessed by the Ishak score combined with Beijing Classification predominantly progressive, indeterminate, and predominately regressive score. Steatosis was evaluated by the nonalcoholic fatty liver disease activity score. Collagen in each site was quantitated by second harmonic generation/two photon excitation fluorescence technology. Serum proteomic changes after treatment were characterized by mass-based spectrometry. A total of 239 CHB patients were included and divided into four groups according to the changes in steatosis: 162 (67.8%) had no steatosis throughout, 24 (10.0%) developed new-onset steatosis, 21 (8.8%) had initial steatosis which disappeared, and 32 (13.4%) had persistent steatosis. The persistent steatosis group showed the lowest rate of fibrosis regression (14/32, 43.8%). Persistent steatosis correlated with decreased fibrosis regression significantly after adjusting for age, sex, fibrosis stage, and metabolic factors at baseline, as well as the viral response (adjusted odds ratio = 0.380, 95% confidence interval 0.145-0.996, p = 0.049). This decreased fibrosis regression was associated with accumulated collagen in the perisinusoidal area. Patients with persistent steatosis showed unique changes in glycolipid metabolism according to the serum proteomic atlas. Persistent steatosis correlated with decreased fibrosis regression during antiviral therapy in patients with CHB.


Assuntos
Fígado Gorduroso , Hepatite B Crônica , Humanos , Fígado/patologia , Vírus da Hepatite B , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/patologia , Antivirais/uso terapêutico , Proteômica , Fígado Gorduroso/patologia , Cirrose Hepática/patologia , Fibrose , Colágeno/uso terapêutico
20.
J Med Virol ; 95(2): e28555, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36738235

RESUMO

Hepatic lobular architecture distortion is a deleterious turning point and a crucial histological feature of advanced liver fibrosis in chronic liver diseases. Regression of fibrosis has been documented in chronic hepatitis B (CHB) patients. However, whether lobular architecture could be restored following fibrosis regression after antiviral therapy is still unclear. Glutamine synthetase (GS) is generally expressed by perivenular hepatocytes around hepatic veins (HV). In this study, we defined abnormal lobular architecture (GSPT ) as GS expressing in the vicinity of portal tracts (PT), which denotes parenchymal extinction and lobular collapse. We defined normal lobular architecture (GSHV ) as GS positivity area not approximating PTs. Therefore, we propose a new GS-index, defined as the percentage of GSHV /(GSHV + GSPT ), to evaluate the extent of architectural disruption and restoration. We evaluated 43 CHB patients with advanced fibrosis (Ishak stage ≥4). Posttreatment liver biopsy was performed after 78 weeks of anti-HBV therapy. The median GS-index improved from 7% (interquartile range [IQR]: 0%-23%) at baseline to 36% (IQR: 20%-57%) at Week 78 (p < 0.001). Totals of 22 patients (51%) had significant GS-index improvement from 0% (IQR: 0%-13%) to 55% (IQR: 44%-81%), while the other half had almost no change between 17% (IQR: 0%-33%) to 20% (IQR: 12%-31%). When GS-index78w ≥ 50% was used to define hepatic lobular restoration, 37% of patients (16/43) achieved lobular restoration, with much improvement in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels (median value of ∆/Baseline in ALT: restored vs. nonrestored was 79.1% vs. 48.8%, p = 0.018; median value of ∆/Baseline in AST: restored vs. nonrestored was 69.1% vs. 32.5%, p = 0.005). More importantly, lobular restoration correlated with fibrosis regression (median value of ∆/Baseline in Ishak stage: restored vs. nonrestored was 25.0% vs. 0%, p = 0.008). Therefore, in the era of antiviral therapy for CHB, restoration of hepatic lobular architecture is achievable in patients with advanced fibrosis. GS-index provides additional insight into fibrosis regression that goes beyond collagen degradation.


Assuntos
Glutamato-Amônia Ligase , Hepatite B Crônica , Humanos , Hepatite B Crônica/tratamento farmacológico , Fígado/patologia , Fibrose , Cirrose Hepática/patologia , Alanina Transaminase , Biópsia , Antivirais/uso terapêutico
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