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1.
Nature ; 626(8000): 792-798, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38297125

RESUMO

Crop production is a large source of atmospheric ammonia (NH3), which poses risks to air quality, human health and ecosystems1-5. However, estimating global NH3 emissions from croplands is subject to uncertainties because of data limitations, thereby limiting the accurate identification of mitigation options and efficacy4,5. Here we develop a machine learning model for generating crop-specific and spatially explicit NH3 emission factors globally (5-arcmin resolution) based on a compiled dataset of field observations. We show that global NH3 emissions from rice, wheat and maize fields in 2018 were 4.3 ± 1.0 Tg N yr-1, lower than previous estimates that did not fully consider fertilizer management practices6-9. Furthermore, spatially optimizing fertilizer management, as guided by the machine learning model, has the potential to reduce the NH3 emissions by about 38% (1.6 ± 0.4 Tg N yr-1) without altering total fertilizer nitrogen inputs. Specifically, we estimate potential NH3 emissions reductions of 47% (44-56%) for rice, 27% (24-28%) for maize and 26% (20-28%) for wheat cultivation, respectively. Under future climate change scenarios, we estimate that NH3 emissions could increase by 4.0 ± 2.7% under SSP1-2.6 and 5.5 ± 5.7% under SSP5-8.5 by 2030-2060. However, targeted fertilizer management has the potential to mitigate these increases.


Assuntos
Amônia , Produção Agrícola , Fertilizantes , Amônia/análise , Amônia/metabolismo , Produção Agrícola/métodos , Produção Agrícola/estatística & dados numéricos , Produção Agrícola/tendências , Conjuntos de Dados como Assunto , Ecossistema , Fertilizantes/efeitos adversos , Fertilizantes/análise , Fertilizantes/estatística & dados numéricos , Aprendizado de Máquina , Nitrogênio/análise , Nitrogênio/metabolismo , Oryza/metabolismo , Solo/química , Triticum/metabolismo , Zea mays/metabolismo , Mudança Climática/estatística & dados numéricos
2.
Nature ; 615(7951): 280-284, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36859547

RESUMO

Phytoplankton blooms in coastal oceans can be beneficial to coastal fisheries production and ecosystem function, but can also cause major environmental problems1,2-yet detailed characterizations of bloom incidence and distribution are not available worldwide. Here we map daily marine coastal algal blooms between 2003 and 2020 using global satellite observations at 1-km spatial resolution. We found that algal blooms occurred in 126 out of the 153 coastal countries examined. Globally, the spatial extent (+13.2%) and frequency (+59.2%) of blooms increased significantly (P < 0.05) over the study period, whereas blooms weakened in tropical and subtropical areas of the Northern Hemisphere. We documented the relationship between the bloom trends and ocean circulation, and identified the stimulatory effects of recent increases in sea surface temperature. Our compilation of daily mapped coastal phytoplankton blooms provides the basis for global assessments of bloom risks and benefits, and for the formulation or evaluation of management or policy actions.


Assuntos
Ecossistema , Eutrofização , Oceanos e Mares , Fitoplâncton , Fitoplâncton/crescimento & desenvolvimento , Temperatura , Movimentos da Água , Medição de Risco , Política Ambiental , Ecologia , Proliferação Nociva de Algas , Clima Tropical , História do Século XXI , Mapeamento Geográfico
3.
Anal Chem ; 96(23): 9379-9389, 2024 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-38805056

RESUMO

Over the years, a number of state-of-the-art data analysis tools have been developed to provide a comprehensive analysis of data collected from gas chromatography-mass spectrometry (GC-MS). Unfortunately, the time shift problem remains unsolved in these tools. Here, we developed a novel comprehensive data analysis strategy for GC-MS-based untargeted metabolomics (AntDAS-GCMS) to perform total ion chromatogram peak detection, peak resolution, time shift correction, component registration, statistical analysis, and compound identification. Time shift correction was specifically optimized in this work. The information on mass spectra and elution profiles of compounds was used to search for inherent landmarks within analyzed samples to resolve the time shift problem across samples efficiently and accurately. The performance of our AntDAS-GCMS was comprehensively investigated by using four complex GC-MS data sets with various types of time shift problems. Meanwhile, AntDAS-GCMS was compared with advanced GC-MS data analysis tools and classic time shift correction methods. Results indicated that AntDAS-GCMS could achieve the best performance compared to the other methods.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Metabolômica , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metabolômica/métodos , Animais , Fatores de Tempo , Análise de Dados
4.
Mol Ecol ; : e17516, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39188110

RESUMO

Both regional species pool and local community assembly mechanism drive the microbial diversity patterns across geographical gradients. However, little has been done to separate their effects on the ß diversity patterns of microbial communities involved in nitrogen (N) cycling in river ecosystems. Here, we use high-throughput sequencing of the archaeal amoA, bacterial amoA, nirK, and nirS genes, null model, and neutral community model to distinguish the relative importance of species pool and local assembly processes for ammonia-oxidizing and denitrifying communities in river wetlands along a latitudinal gradient in eastern China. Results indicated that the ß diversity of the nirS-type denitrifying community co-varied with γ diversity and environmental heterogeneity, implying that regional species pool and heterogeneous selection explained variation in ß diversity. However, the ß diversity of ammonia-oxidizing and nirK-type denitrifying communities did not correlate with γ diversity and environmental heterogeneity. The continuous hump distribution of ß deviation along the latitudinal gradient and the lower species dispersal rate indicated that the dispersal limitation shaped the variation in ß diversity of ammonia-oxidizing and nirK-type denitrifying communities. Additionally, biotic interactions drove ammonia-oxidizing and nirS-type denitrifying communities by influencing species co-occurrence patterns. Our study highlights the importance of regional species pool and local community assembly processes in shaping geographical patterns of N-cycling microorganisms and extends knowledge of their adaptability to a continuously changing environment on a large scale.

5.
Acc Chem Res ; 56(2): 169-186, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36571794

RESUMO

ConspectusThe past decades have witnessed tremendous progress on radical reactions. However, in comparison with carbon, nitrogen, oxygen, and other main group element centered radicals, the synthetic chemistry of boron centered radicals was less studied, mainly due to the high electron-deficiency and instability of such 3-center-5-electron species. In the 1980s, Roberts and co-workers found that the coordination of a Lewis base (amines or phosphines) with the boron center could form 4-center-7-electron boryl radicals (Lewis base-boryl radicals, LBRs) that are found to be more stable. However, only limited synthetic applications were developed. In 2008, Curran and co-workers achieved a breakthrough with the discovery of N-heterocyclic carbene (NHC) boryl radicals, which could enable a range of radical reduction and polymerization reactions. Despite these exciting findings, more powerful and valuable synthetic applications of LBRs would be expected, given that the structures and reactivities of LBRs could be easily modulated, which would provide ample opportunities to discover new reactions. In this Account, a summary of our key contributions in LBR-enabled radical borylation reactions and selective activation of inert carbon-heteroatom bonds will be presented.Organoboron compounds have shown versatile applications in chemical society, and their syntheses rely principally on ionic borylation reactions. The development of mechanistically different radical borylation reactions allows synthesizing products that are inaccessible by traditional methods. For this purpose, we progressively developed a series of NHC-boryl radical mediated chemo-, regio-, and stereoselective radical borylation reactions of alkenes and alkynes, by which a wide variety of structurally diverse organoboron molecules were successfully prepared. The synthetic utility of these borylated products was also demonstrated. Furthermore, we disclosed a photoredox protocol for oxidative generation of NHC-boryl radicals, which enabled useful defluoroborylation and arylboration reactions.Selective bond activation is an ideal way to convert simple starting materials to value-added products, while the cleavage of inert chemical bonds, in particular the chemoselectivity control when multiple identical bonds are present in similar chemical environments, remains a long-standing challenge. We envisaged that finely tuning the properties of LBRs might provide a new solution to address this challenge. Recently, we disclosed a 4-dimethylaminopyridine (DMAP)-boryl radical promoted sequential C-F bond functionalization of trifluoroacetic acid derivatives, in which the α-C-F bonds were selectively snipped via a spin-center shift mechanism. This strategy enables facile conversion of abundantly available trifluoroacetic acid to highly valuable mono- and difluorinated molecules. Encouraged by this finding, we further developed a boryl radical enabled three-step sequence to construct all-carbon quaternary centers from a range of trichloromethyl groups, where the three C-Cl bonds were selectively cleaved by the rational choice of suitable boryl radical precursors in each step. Furthermore, a boryl radical promoted dehydroxylative alkylation of α-hydroxy carboxylic acid derivatives was achieved, allowing for the efficient conversion of some biomass platform molecules to high value products.

6.
J Environ Manage ; 365: 121509, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38897088

RESUMO

The Qinghai-Tibetan Plateau harbors rich and diverse wetlands that provide multiple ecological functions simultaneously. Although the relationships between biodiversity and wetland functioning have been well studied in recent decades, the links between the multiple features of plant and microbial communities and soil multifunctionality (SMF) remain unknown in the high-altitude wetlands that are extremely sensitive to human disturbance. Here, using the single function, averaging, weighted, and multiple-threshold methods, we calculated the SMF of Qinghai-Tibetan wetlands based on 15 variables associated with soil nutrient status, nutrient cycle, and greenhouse gas emission. We then related SMF to multidimensional (species, phylogenetic, and functional) diversity of plants and soil microorganisms and microbial network modules. The results showed that plant diversity explained more variance in SMF than soil microbial diversity, and plant species richness and phylogenetic distance were positive predictors of SMF. Bacterial network modules were more positively related to SMF than fungal network modules, and the alpha diversity of bacterial network modules contributed more to SMF than the diversity of the whole bacterial community. Pediococcus, Hirsutella, and Rhodotorula were biomarkers for SMF and had significant relationships with nitrogen mineralization and greenhouse gas emissions. Together, these results highlight the importance of plant diversity and bacterial network modules in determining the SMF, which are crucial to predicting the response of ecosystem functioning to biodiversity loss under intensifying anthropogenic activities.


Assuntos
Biodiversidade , Microbiologia do Solo , Solo , Áreas Alagadas , Tibet , Solo/química , Plantas , Filogenia , Ecossistema , Bactérias/classificação
7.
Angew Chem Int Ed Engl ; 63(25): e202405863, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38589298

RESUMO

Cascade radical cyclization constitutes an atom- and step-economic route for rapid assembly of polycyclic molecular skeletons. Although an array of redox-active metal catalysts has recently shown robust applications in enabling various catalytic cascade radical processes, the use of free organic radical as the catalyst, which is capable of triggering strategically distinct cascades, has rarely been developed. Here, we disclosed that the benzimidazolium-based N-heterocyclic carbene (NHC)-boryl radical is capable of catalyzing cascade cyclization reactions in both intra- and intermolecular pathways, assembling [5,5] fused bicyclic and [6,6,6] fused tricyclic molecules, respectively. The catalytic reactions start with the chemo- and regioselective addition of the boryl radical catalyst to a tethered alkene or alkyne moiety, followed by either an intramolecular formal [3+2] or an intermolecular [2+2+2] cycloaddition process to construct bicyclo[3.3.0]octane or tetrahydrophenanthridine skeletons, respectively. Eventually, a ß-elimination occurs to release the boryl radical catalyst, completing a catalytic cycle. High to excellent diastereoselectivity is achieved in both catalytic reactions under substrate control.

8.
Pharmacol Res ; 190: 106737, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36940891

RESUMO

BACKGROUND: Nucleotide analogs treatment can reverse liver fibrosis in chronic hepatitis B (CHB). However, it has limited effect on fibrosis resolution in patients with CHB, particularly in preventing progression to hepatocellular carcinoma (HCC). Ruangan granule (RG), a Chinese herbal formula, has proven to produce a therapeutic effect against liver fibrosis in animal experiment. Thus, we aimed to evaluate the effect of our Chinese herbal formula (RG) combined with entecavir (ETV) to reverse advanced liver fibrosis/early cirrhosis from CHB. METHODS: A total of 240 CHB patients with histologically confirmed advanced liver fibrosis/early cirrhosis from 12 centers were randomly and blindly allocated to consume either ETV (0.5 mg/day) plus RG (2 times/day) or control (ETV) for 48 weeks (wk) treatment. Changes in histopathology, serology and imageology were observed. Liver fibrosis reversion, defined as a reduction in the Knodell HAI score by ≥ 2 points and Ishak score by ≥ 1 grade, was assessed. RESULTS: The rate of fibrosis regression and inflammation remission after 48 wk of treatment in histopathology was significantly higher in the ETV + RG group (38.73% vs. 23.94%, P = 0.031). The ultrasonic semiquantitative scores decreased by ≥ 2 points and were 41 (28.87%) and 15 (21.13%) in the ETV+RG and ETV groups, respectively (P = 0.026). The ETV+RG group had a significantly lower Fibrosis-4 score (FIB-4) index (P = 0.028). There was a significant difference between the ETV+RG and ETV groups in the liver function normalization rate (P < 0.01). Moreover, ETV plus RG combination treatment further reduced the risk of HCC in median 55-month follow-up (P < 0.01). CONCLUSIONS: This study illustrates that the Chinese herbal formula RG with ETV can improve advanced liver fibrosis/early cirrhosis regression in patients with CHB, further reducing the risk of HCC.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Animais , Vírus da Hepatite B , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Antivirais/uso terapêutico , Antivirais/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Resultado do Tratamento , Neoplasias Hepáticas/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia
9.
Environ Sci Technol ; 57(16): 6415-6424, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37068375

RESUMO

Microplastics and nanoplastics (MNPs) contamination is an emerging environmental and public health concern, and these particles have been reported both in aquatic and terrestrial ecosystems. Recent studies have expanded our understanding of the adverse effects of MNPs pollution on human, terrestrial, and aquatic animals, insects, and plants. In this perspective, we describe the adverse effects of MNPs particles on pollinator and plant health and discuss the mechanisms by which MNPs disrupt the pollination process. We discuss the evidence and integrate transcriptome studies to investigate the negative effects of MNPs on the molecular biology of pollination, which may cause delay or inhibit the pollination services. We conclude by addressing challenges to plant-pollinator health from MNPs pollution and argue that such harmful effects disrupt the communication between plant and pollinator for a successful pollination process.


Assuntos
Microplásticos , Polinização , Animais , Humanos , Plásticos , Ecossistema , Plantas , Biologia
10.
BMC Public Health ; 23(1): 1677, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37653372

RESUMO

OBJECTIVE: To investigate the influence of subjective exercise experience on adolescent trait anxiety and to reveal the mediating effect of exercise behavior. METHODS: Using the Subjective Exercise Experience Scale (SEES), Physical Exercise Rating Scale (PARS-3), and Trait Anxiety Inventory (T-AI), a questionnaire survey was conducted among 500 adolescents in Southwest China, and the SPSS21.0 and AMOS21.0 statistical analysis software was used to statistics and analysis on the questionnaires. RESULTS: 1) Among adolescents, the exercise behavior of boys was significantly higher than that of girls (p < 0.05), and the subjective exercise experience of students aged 9 to 12 was significantly higher than that of students aged 12 to 15 (p < 0.05). 2) The subjective exercise experience could directly and positively predict exercise behavior (ß = 0.45, p < 0.001) and negatively predict trait anxiety (ß = -0.26, p < 0.05), and exercise behavior could directly and negatively predict trait anxiety (ß = -0.32, p < 0.01). 3) The exercise behavior played a partial mediating effect between subjective exercise experience and trait anxiety (the mediation effect was -0.14). Among them, compared with low- and high-exercise amounts, the exercise behavior of moderate exercise amounts had the strongest mediating effect between subjective exercise experience and trait anxiety. CONCLUSION: The good subjective exercise experience not only has direct benefits for improving trait anxiety in adolescents but also helps to improve their exercise behavior, enrich daily physical exercise activities, and indirectly promote the reduction of trait anxiety.


Assuntos
Transtornos de Ansiedade , Ansiedade , Masculino , Feminino , Adolescente , Humanos , China , Exercício Físico , Fenótipo
11.
Molecules ; 28(9)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37175098

RESUMO

With the increased incidence of wine fraud, a fast and reliable method for wine certification has become a necessary prerequisite for the vigorous development of the global wine industry. In this study, a classification strategy based on three-dimensional fluorescence spectroscopy combined with chemometrics was proposed for oak-barrel and stainless steel tanks with oak chips aged wines. Principal component analysis (PCA), partial least squares analysis (PLS-DA), and Fisher discriminant analysis (FDA) were used to distinguish and evaluate the data matrix of the three-dimensional fluorescence spectra of wines. The results showed that FDA was superior to PCA and PLS-DA in classifying oak-barrel and stainless steel tanks with oak chips aged wines. As a general conclusion, three-dimensional fluorescence spectroscopy can provide valuable fingerprint information for the identification of oak-barrel and stainless steel tanks with oak chips aged wines, while the study will provide some theoretical references and standards for the quality control and quality assessment of oak-barrel aged wines.


Assuntos
Quercus , Vinho , Vinho/análise , Aço Inoxidável , Quercus/química , Espectrometria de Fluorescência , Quimiometria , Madeira/química
12.
J Am Chem Soc ; 144(33): 15275-15285, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35950969

RESUMO

The construction of diversely substituted all-carbon quaternary centers has been a longstanding challenge in organic synthesis. Methods that add three alkyl substituents to a simple C(sp3) atom rely heavily on lengthy multiple processes, which usually involve several preactivation steps. Here, we describe a straightforward three-step sequence that uses a range of readily accessible activated trichloromethyl groups as the carbon source, the three C-Cl bonds of which are selectively functionalized to introduce three alkyl chains. In each step, only a single C-Cl bond was cleaved with the choice of an appropriate Lewis base-boryl radical as the promoter. A vast range of diversely substituted all-carbon quaternary centers could be accessed directly from these activated CCl3 trichloromethyl groups or by simple derivatizations. The use of different alkene traps in each of the three steps enabled facile collections of a large library of products. The utility of this strategy was demonstrated by the synthesis of variants of two drug molecules, whose structures could be easily modulated by varying the alkene partner in each step. The results of kinetic and computational studies enabled the design of the three-step reaction and provided insights into the reaction mechanisms.


Assuntos
Alcenos , Carbono , Alcenos/química , Carbono/química , Técnicas de Química Sintética
13.
Anal Chem ; 94(22): 7944-7951, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35616317

RESUMO

High-quality oxygen isotope analysis of composition-variable minerals (e.g., ubiquitous carbonates) using secondary ion mass spectrometry (SIMS) is extremely challenging. The classical off-line procedure, which requires additional electron probe microanalyzer (EPMA) chemical compositions for calibrating instrumental mass fractionation (IMF), is inherently inaccurate and analytically inefficient. In this study, the first accurate and paired SIMS analysis of δ18O and Fe# [molar Fe/(Mg + Fe)] in dolomite is reported. Based on five newly developed dolomite O-isotopic standards with an Fe# range of 0.01-0.35 obtained by SIMS, a novel accurate and rapid online matrix effect calibration method for dolomite O-isotope analysis was developed using concurrent SIMS 18O-16O-56Fe16O-24Mg16O measurements without additional chemical electron probe microanalysis. A logistic equation was proposed as the best-fit curve to represent the δ18O matrix effect based on the 56Fe16O/24Mg16O ratios. For CTD-4 carbonatitic dolomite with variable Fe# but homogeneous oxygen isotopes, the off-line method exhibited highly variable apparent δ18O values in the range of 5.74-10.11‰. The online method yielded a homogeneous δ18O value of 7.94 ± 0.34‰ (2SD, n = 40), which is comparable with that of bulk analysis (7.94 ± 0.20‰; 2SD). Comprehensive analyses validated the online method as the best strategy for performing accurate δ18O analysis of samples with highly heterogeneous compositions. Based on its accuracy, simplicity, and economic feasibility, this method has potential applications in the analysis of composition-complex dolomites, detrital dolomites, and other precious terrestrial and extraterrestrial materials.


Assuntos
Carbonato de Cálcio , Minerais , Carbonato de Cálcio/química , Calibragem , Magnésio , Isótopos de Oxigênio/química
14.
Reprod Biol Endocrinol ; 20(1): 124, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35986323

RESUMO

BACKGROUND: Patients with recurrent implantation failure (RIF) may have more uterine contractions. Several observational studies suggested that atosiban administration around embryo transfer resulted in higher pregnancy rates in RIF patients. This study aimed to evaluate the effect of atosiban given before fresh embryo transfer on pregnancy outcomes of women with RIF. METHODS: A prospective, randomized, double-blind controlled clinical trial was performed in IVF center of Shanghai First Maternity and Infant Hospital. According to a computer-generated randomization list, 194 infertile women with RIF received fresh embryo transfer between July 2017 and December 2019 were randomly allocated into the atosiban (n = 97) and the placebo (n = 97) groups. Women in the treatment group received atosiban intravenously about 30 min before embryo transfer with a bolus dose of 6.75 mg over one minute. Those in the placebo group received only normal saline infusion for the same duration. RESULTS: There was no significant difference in the live birth rate between the atosiban and placebo groups (42.3% vs 35.1%, P = 0.302, RR = 1.206 (0.844-1.723)). No significant differences were found between the two groups in the positive pregnancy test, clinical pregnancy, ongoing pregnancy, miscarriage, multiple pregnancy, ectopic pregnancy and implantation rates. Similar results were found when stratified by the number of embryos previously transferred, number of previous failed embryo transfers, frequency of endometrial peristalsis on embryo transfer day (≥ 3 waves/min) or serum estradiol (E2) on the day of hCG above the median level. And, there was no correlation between the serum E2 level on the day of hCG and the frequency of endometrial peristalsis on embryo transfer day. The frequency of endometrial peristalsis on embryo transfer day, total FSH/HMG dosage and duration were the significant factors which independently predicted the likelihood of a live birth. CONCLUSIONS: These results suggested that atosiban treatment before fresh embryo transfer might not improve the live birth rate in RIF patients. TRIAL REGISTRATION: The study had been approved by the Institutional Review Board of the hospital (2017 ethics No.43) and was registered under Clinicaltrials.gov with an identifier NCT02893722.


Assuntos
Fertilização in vitro , Infertilidade Feminina , China , Implantação do Embrião , Feminino , Fertilização in vitro/métodos , Humanos , Infertilidade Feminina/terapia , Nascido Vivo , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Vasotocina/análogos & derivados
16.
Acta Pharmacol Sin ; 43(6): 1484-1494, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34497374

RESUMO

The epigenetic modification of hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) plays a crucial role in cccDNA transcription and viral persistence. Interferon-α (IFN-α) is a pivotal agent against HBV cccDNA. However, the mechanism by which IFN-α modulates the epigenetic regulation of cccDNA remains poorly understood. In this study, we report that IFN-α2b enhances the histone deacetylase 3 (HDAC3)-mediated de-2-hydroxyisobutyrylation of histone H4 lysine 8 (H4K8) on HBV cccDNA minichromosome to restrict the cccDNA transcription in liver. By screening acetyltransferases and deacetylases, we identified that HDAC3 was an effective restrictor of HBV transcription and replication. Moreover, we found that HDAC3 was able to mediate the de-2-hydroxyisobutyrylation of H4K8 in HBV-expressing hepatoma cells. Then, the 2-hydroxyisobutyrylation of histone H4K8 (H4K8hib) was identified on the HBV cccDNA minichromosome, promoting the HBV transcription and replication. The H4K8hib was regulated by HDAC3 depending on its deacetylase domain in the system. The low level of HDAC3 and high level of H4K8hib were observed in the liver tissues from HBV-infected human liver-chimeric mice. The levels of H4K8hib on HBV cccDNA minichromosome were significantly elevated in the liver biopsy specimens from clinical hepatitis B patients, which was consistent with the high transcriptional activity of cccDNA. Strikingly, IFN-α2b effectively facilitated the histone H4K8 de-2-hydroxyisobutyrylation mediated by HDAC3 on the HBV cccDNA minichromosome in primary human hepatocytes and hepatoma cells, leading to the inhibition of HBV transcription and replication. Our finding provides new insights into the mechanism by which IFN-α modulates the epigenetic regulation of HBV cccDNA minichromosome.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Carcinoma Hepatocelular/genética , DNA Circular/farmacologia , DNA Viral/genética , DNA Viral/farmacologia , Epigênese Genética , Vírus da Hepatite B/genética , Histona Desacetilases , Histonas/metabolismo , Humanos , Interferon-alfa/genética , Interferon-alfa/metabolismo , Interferon-alfa/farmacologia , Neoplasias Hepáticas/genética , Camundongos , Replicação Viral
17.
Cell Mol Life Sci ; 79(1): 44, 2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-34971424

RESUMO

Triacylglycerol lipase (TGL) is an essential lipid metabolism enzyme that also plays a critical role in energy metabolism; however, how it regulates other life processes is unknown. To investigate the functional role of TGL in moth reproduction, males Sitotroga cerealella were used as a model. The TGL gene was cloned and analysed. The results showed that the open reading frame of TGL was 1968 bp long and contained three conserved regions. TGL gene expression was higher in the larval and early adult stages than in the pupal stage, with the highest levels observed in the fat body, testis and accessory glands during the early adult stage. Moreover, after TGL in male adults was silenced through RNAi, the protein content in male accessory glands remained unchanged, and the spermatophore transferred into females mated with TGL-silenced males became small and empty; meanwhile, the number of apyrene sperm in the spermatophore was significantly reduced due to the reduction of apyrene sperm in males, which eventually led to the significant reduction of egg-laying amount. All of the findings suggest that TGL regulates the amount of sperm in male moths as well as the morphology and quality of spermatophores transferred to females after mating with treated males, implying that TGL is critical for Sitotroga cerealella's reproductive process.


Assuntos
Lipase/fisiologia , Reprodução , Testículo/metabolismo , Animais , Larva/metabolismo , Masculino , Mariposas
18.
Neoplasma ; 69(4): 931-939, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35652620

RESUMO

Natural killer (NK) cells typically function as frontline lymphocytes against cancer although little is known about their engagement in non-small cell lung cancer (NSCLC). This study compared the performance and activity of NK cells and their subsets in the peripheral blood of NSCLC sufferers and healthy participants. In total, 67 healthy controls (40 males; 59.7%) and 56 patients with NSCLC (35 males; 62.5%) were included (mean age, 66.6 years). Flow cytometry identified NK cells and their subpopulations in external blood, and the total number, proportion, activity, surface activating, and inhibitory receptor expression levels were determined. Results showed that NK cell surface receptors CD107a, IFN-γ, and TNF-α activity were markedly reduced in lung cancer patients compared to healthy controls. The number and ratio of NK cells within the lymphocyte population were decreased in patients. The concentration of the inhibitory receptors TIGIT, TIM-3, CD96, PD-1, and Siglec-7 were increased in patients, whereas the expression level of the activating receptor NKP30 was decreased. Moreover, the expression levels of IFN-γ, TIGIT, CD96, PD-1, and TIM-3 were correlated with the clinical phase of NSCLC. These findings suggest that surface receptors from NK cells are likely to be involved in the evolution of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Idoso , Antígenos CD/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Humanos , Células Matadoras Naturais , Neoplasias Pulmonares/metabolismo , Masculino , Receptor de Morte Celular Programada 1/metabolismo , Receptores Imunológicos/metabolismo
19.
Ecotoxicol Environ Saf ; 248: 114304, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36403303

RESUMO

Environmental pollution and resistance in animals are major concerns for the application of synthetic pesticides. Diallyl trisulfide (DAT), an active compound in garlic essential oil, is a novel tool for active and safe control of agricultural insect pests. In this study, we analysed the effects of DAT (0.01 µL/L) on the protein content in male reproductive tissues (accessory glands, ejaculatory ducts, and testis), and juvenile hormone (JH) and ecdysone titres in a highly detrimental pest of stored products, Sitotroga cerealella. Evaluation of the expression profile of JH and ecdysone pathway-related genes in various tissues indicated that the accessory gland protein and ecdysone titres were markedly decreased after DAT fumigation, whereas the testis protein content and JH titre were increased. However, the protein content of the ejaculatory ducts remained unchanged between the treated and control groups. Further investigation revealed that DAT disrupted the mRNA expression of key enzymes involved in JH and ecdysone pathways. While increased mRNA levels of juvenile hormone acid O-methyltransferase (JHMAT) and Kruppel homologue 1 (Kr-h1) were observed after 4 and 7 h of DAT fumigation, the levels of juvenile hormone epoxide hydrolase (JHEH) were substantially reduced 3 h post-fumigation. mRNA levels of the ecdysone-responsive gene, FTZF1, and cytochrome P450 enzyme, CYP315A1, were notably decreased at 7 h and 4 h, respectively, post-fumigation, whereas CYP314A1 and CYP302A1 mRNA levels decreased after 3 h and 4 h, respectively. While DAT fumigation disrupted sperm number in the testis, ejaculatory ducts, and seminal vesicles, topical application of the 20-hydroxyecdysone (20E) analogue also lowered sperm number in the ejaculatory ducts. Topical application of methoprene, a JH analogue, increased the protein content in the testes, but not in the accessory glands or ejaculatory ducts. However, the survival rate was not affected by the topical application of methoprene or 20E. These data suggest that DAT regulates JH and ecdysone via its molecular pathway genes and modulates endocrine secretion during the male reproductive process.


Assuntos
Ecdisona , Alho , Masculino , Animais , Metoprene , Sementes , Hormônios Juvenis/farmacologia
20.
Genomics ; 113(4): 2276-2289, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33965547

RESUMO

BACKGROUND/AIM: There has been increasing evidence for the function of long non-coding RNA (lncRNA) in nasopharyngeal carcinoma (NPC). We aim to delve into the position of lncRNA HOX antisense intergenic RNA (HOTAIR), together with enhancer of zeste homolog 2 (EZH2), E-cadherin and trimethylation of lysine 27 on histone H3 (H3K27me3) in NPC. METHODS: HOTAIR, EZH2, and E-cadherin expression in NPC tissues and cells were tested. NPC cell biological functions were examined through gain-of and loss-of function assays. The mechanism of lncRNA HOTAIR/E-cadherin/EZH2/H3K27 axis in NPC was decoded. RESULTS: LncRNA HOTAIR and EZH2 were highly expressed in NPC, and E-cadherin was lowly expressed. Down-regulation of HOTAIR or EZH2 inhibited NPC cell progression and tumor growth. HOTAIR recruited histone methylase EZH2 to mediate trimethylation of H3K27 and regulated E-cadherin expression. CONCLUSION: HOTAIR inhibits E-cadherin by stimulating the trimethylation of H3K27 to promote NPC cell progression through recruiting histone methylase EZH2.


Assuntos
Neoplasias Nasofaríngeas , RNA Longo não Codificante , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Regulação Neoplásica da Expressão Gênica , Histona Metiltransferases/genética , Histona Metiltransferases/metabolismo , Humanos , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
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