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1.
Plant Cell Rep ; 43(11): 258, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39384635

RESUMO

KEY MESSAGE: Hydrogen peroxide promoted leaf senescence by sulfenylating the magnesium chelating protease I subunit (CHLI1) in the chlorophyll synthesis pathway, and inhibited its activity to reduce chlorophyll synthesis. Leaf senescence is the final and crucial stage of plant growth and development, during which chlorophyll experiences varying degrees of destruction. It is well-known that the higher ROS accumulation is a key factor for leaf senescence, but whether and how ROS regulates chlorophyll synthesis in the process are unknown. Here, we report that H2O2 inhibits chlorophyll synthesis during leaf senescence via the I subunit of magnesium-chelatase (CHLI1). During leaf senescence, the decrease of chlorophyll content is accompanied by the increase of H2O2 accumulation, as well as the inhibition of catalase (CAT) genes expression. The mutant cat2-1, with increased H2O2 shows an accelerated senescence phenotype and decreased CHLI1 activity compared with the wild type. H2O2 inhibits CHLI1 activity by sulfenylating CHLI1 during leaf senescence. Consistent with this, the chli1 knockout mutant displays the same premature leaf senescence symptom as cat2-1, while overexpression of CHLI1 in cat2-1 can partially restore its early senescence phenotype. Taken together, these results illustrate that CAT2-mediated H2O2 accumulation during leaf senescence represses chlorophyll synthesis through sulfenylating CHLI1, and thus inhibits its activity, providing a new insight into the pivotal role of chlorophyll synthesis as a participant in orchestrating the leaf senescence.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Catalase , Clorofila , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio , Folhas de Planta , Senescência Vegetal , Folhas de Planta/metabolismo , Folhas de Planta/genética , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Clorofila/metabolismo , Peróxido de Hidrogênio/metabolismo , Arabidopsis/genética , Arabidopsis/fisiologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Senescência Vegetal/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Catalase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Liases
2.
J Environ Manage ; 367: 121960, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39111009

RESUMO

Substituting mineral fertilizer with manure or a combination of organic amendments plus beneficial soil microorganisms (bio-manure) in agriculture is a standard practice to mitigate N2O and NO emissions while enhancing crop performance and nitrogen use efficiency (NUE). Here, we conducted a greenhouse trial for three consecutive vegetable growth seasons for Spinach, Coriander herb, and Baby bok choy to reveal the response of N2O and NO emissions, NUE, and vegetable quality index (VQI) to fertilization strategies. Strategies included solely chemical nitrogen fertilizer (CN), 20 (M1N4) and 50% (M1N1) substitution with manure, 20 (BM1N4) and 50% (BM1N1) substitution with bio-manure, and no fertilization as a control and were organized in a completely randomized design (n = 3). Manure decreased N2O emissions by 24-45% and bio-manure by 44-53% compared to CN. Manure reduced NO emissions by 28-41% and bio-manure by 55-63%. Bio-manure increased NUE by 0.04-31% and yields by 0.05-61% while improving VQI, attributed to yield growth and reduced vegetable NO3- contents. Improvement of root growth was the main factor that explained the rise of NUE; NUE declined with the increase of N2O emissions, showing the loss of vegetable performance under conditions when denitrification processes prevailed. Under the BM1N1, the highest VQI and the lowest yield-scaled N-oxide emissions were observed, suggesting that substitution with bio-manure can improve vegetable quality and mitigate N-oxide emissions. These findings indicate that substituting 50% of mineral fertilizer with bio-manure can effectively improve NUE and VQI and mitigate N-oxides in intensive vegetable production.


Assuntos
Fertilizantes , Esterco , Nitrogênio , Solo , Verduras , Verduras/crescimento & desenvolvimento , Nitrogênio/metabolismo , Fertilizantes/análise , Solo/química , Agricultura/métodos , Óxido Nitroso/análise , Óxido Nitroso/metabolismo
3.
BMC Genomics ; 24(1): 332, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322453

RESUMO

The rich genetic diversity in Citrullus lanatus and the other six species in the Citrullus genus provides important sources in watermelon breeding. Here, we present the Citrullus genus pan-genome based on the 400 Citrullus genus resequencing data, showing that 477 Mb contigs and 6249 protein-coding genes were absent in the Citrullus lanatus reference genome. In the Citrullus genus pan-genome, there are a total of 8795 (30.5%) genes that exhibit presence/absence variations (PAVs). Presence/absence variation (PAV) analysis showed that a lot of gene PAV were selected during the domestication and improvement, such as 53 favorable genes and 40 unfavorable genes were identified during the C. mucosospermus to C. lanatus landrace domestication. We also identified 661 resistance gene analogs (RGAs) in the Citrullus genus pan-genome, which contains 90 RGAs (89 variable and 1 core gene) located on the pangenome additional contigs. By gene PAV-based GWAS, 8 gene presence/absence variations were found associated with flesh color. Finally, based on the results of gene PAV selection analysis between watermelon populations with different fruit colors, we identified four non-reference candidate genes associated with carotenoid accumulation, which had a significantly higher frequency in the white flesh. These results will provide an important source for watermelon breeding.


Assuntos
Citrullus , Citrullus/genética , Domesticação , Melhoramento Vegetal , Genoma de Planta , Análise de Sequência de DNA
4.
J Am Chem Soc ; 145(35): 19283-19292, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37585603

RESUMO

Precise tailoring of the aggregation state of covalent organic frameworks (COFs) to form a hierarchical porous structure is critical to their performance and applications. Here, we report a one-pot and one-step strategy of using dynamic combinatorial chemistry to construct imine-based hollow COFs containing meso- and macropores. It relies on a direct copolymerization of three or more monomers in the presence of two monofunctional competitors. The resulting particle products possess high crystallinity and hierarchical pores, including micropores around 0.93 nm, mesopores widely distributed in the range of 3.1-32 nm, and macropores at about 500 nm, while the specific surface area could be up to 748 m2·g-1, with non-micropores accounting for 60% of the specific surface area. The particles demonstrate unique advantages in the application as nanocarriers for in situ loading of Pd catalysts at 93.8% loading efficiency in the copolymerization of ethylene and carbon monoxide. The growth and assembly of the copolymer could thus be regulated to form flower-shaped particles, efficiently suppressing the fouling of the reactor. The copolymer's weight-average molecular weight and the melting temperature are also highly improved. Our method provides a facile way of fabricating COFs with hierarchical pores for advanced applications in catalysis.

5.
Int J Cancer ; 153(8): 1436-1447, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37306091

RESUMO

Multiple myeloma (MM) is a relapsing clonal plasma cell malignancy and incurable thus far. With the increasing understanding of myeloma, highlighting the critical importance of the immune system in the pathogenesis of MM is essential. The immune changes in MM patients after treatment are associated with prognosis. In this review, we summarize currently available MM therapies and discuss how they affect cellular immunity. We find that the modern anti-MM treatments enhance antitumour immune responses. A deeper understanding of the therapeutic activity of individual drugs offers more effective treatment approaches that enhance the beneficial immunomodulatory effects. Furthermore, we show that the immune changes after treatment in MM patients can provide useful prognostic marker. Analysing cellular immune responses offers new perspectives for evaluating clinical data and making comprehensive predictions for applying novel therapies in MM patients.


Assuntos
Mieloma Múltiplo , Humanos , Imunoterapia , Recidiva Local de Neoplasia , Plasmócitos , Imunidade Celular
6.
J Environ Manage ; 330: 117178, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36621315

RESUMO

Soil nitrification driven by ammonia-oxidizing microorganisms is the most important source of nitrous oxide (N2O) and nitric oxide (NO). Biochar amendment has been proposed as the most promising measure for combating climate warming; both have the potential to regulate the soil nitrification process. However, the comprehensive impacts of different aged biochars and warming combinations on soil nitrification-related N2O and NO production are not well understood. Here, 1-octyne and acetylene were used to investigate the relative contributions of ammonia-oxidizing bacteria (AOB) and archaea (AOA) to potential nitrification-mediated N2O and NO production from the fertilized vegetable soil with different aged biochar amendments and soil temperatures in microcosm incubations. Results demonstrated that AOB dominated nitrification-related N2O and NO production across biochar additions and climate warming. Biochar amendment did not significantly influence the relative contribution of AOB and AOA to N2O and NO production. Field-aged biochar markedly reduced N2O and NO production via inhibiting AOB-amoA gene abundance and AOB-dependent N2O yield while fresh- and lab-aged biochar produced negligible effects on AOB-dependent N2O yield. Climate warming significantly increased N2O production and AOB-dependent N2O yield but less so on NO production. Notably, the relative contribution of AOB to N2O production was enhanced by climate warming, whereas AOB-derived NO showed the opposite tendency. Overall, the results revealed that field-aged biochar contributed to mitigating warming-induced increases in N2O and NO production via inhibiting AOB-amoA gene abundance and AOB-dependent N2O yield. Our findings provided guidance for mitigating nitrogen oxide emissions in intensively managed vegetable production under the context of biochar amendments and climate warming.


Assuntos
Óxido Nítrico , Verduras , Nitrificação , Amônia , Microbiologia do Solo , Archaea , Óxido Nitroso/análise , Solo , Oxirredução
7.
Ecotoxicol Environ Saf ; 242: 113932, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35914399

RESUMO

Chemical fertilization in excess and warming disrupt the soil microbes and alter resource stoichiometry, particularly in intensive vegetable soils, while the effects of these variables on the temperature sensitivity of soil organic carbon (SOC) decomposition (Q10) and SOC stability remain elusive. Thus, we collected six long-term vegetable soils along a climatic gradient to examine the microbial mechanisms and resource stoichiometry effects on fluctuations in Q10 and SOC stability induced by warming and fertilization from vegetable soils. Our results showed that the SOC decomposition was dominated by microbes and regulated by stoichiometry. Compared to cold sites, higher Q10 of SOC decomposition was observed in warm sites, accompanied by lower enzyme activities, microbial CUE, and C:N ratio. In this context, warming reduced SOC stability as evidenced by up to 31.8% greater Q10 (1.45) at warm sites than at cold sites (1.10) owing to less richness of microbial communities and lower microbial CUE. The relatively lower pH and labile organic C value restricted the development of microbial richness, and decreased C- and N-related enzyme activities and a lower C:N ratio resulted in microbial CUE reduction. Additionally, N fertilization altered the C:N imbalance and enhanced SOC stability in vegetable soils, exhibiting an increase of Q10 values, particularly of great importance in warm sites. Collectively, our findings emphasize the importance of the microbial mechanism and resource stoichiometry in predicting variations in Q10 and fluctuations in SOC stability, and provide theoretical advice on improving management policies in the context of warming and fertilization from vegetable soils.


Assuntos
Carbono , Solo , Carbono/química , China , Nitrogênio/análise , Solo/química , Microbiologia do Solo , Verduras
8.
Nano Lett ; 21(5): 1935-1942, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33635654

RESUMO

Optical imaging with nanometer resolution offers fundamental insights into light-matter interactions. Traditional optical techniques are diffraction limited with a spatial resolution >100 nm. Optical super-resolution and cathodoluminescence techniques have higher spatial resolutions, but these approaches require the sample to fluoresce, which many materials lack. Here, we introduce photoabsorption microscopy using electron analysis, which involves spectrally specific photoabsorption that is locally probed using a scanning electron microscope, whereby a photoabsorption-induced surface photovoltage modulates the secondary electron emission. We demonstrate spectrally specific photoabsorption imaging with sub-20 nm spatial resolution using silicon, germanium, and gold nanoparticles. Theoretical analysis and Monte Carlo simulations are used to explain the basic trends of the photoabsorption-induced secondary electron signal. Based on our current experiments and this analysis, we expect that the spatial resolution can be further improved to a few nanometers, thereby offering a general approach for nanometer-scale optical spectroscopic imaging and material characterization.

9.
J Environ Manage ; 313: 114972, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35378346

RESUMO

Biochar is widely used for soil carbon sequestration and fertility improvement. However, the effects of biochar interacted with nitrogen (N) on the mineralization of soil organic carbon (SOC) and microbial community have not been thoroughly understood, particularly no reports have been published on the long term effects of biochar in vegetable field. Here, we examined soil properties, SOC mineralization and microbial community affecting by biochar (0, 20 and 40 t ha-1; C0, C1 and C2, respectively), N (0 or 240 t ha-1; N0 or N1, respectively) and their interaction in a greenhouse vegetable field. Results indicated that biochar addition increased soil pH, SOC, recalcitrant C pool, especially for the 40 t ha-1 treatment. Biochar addition generally decreased soil C-cycling enzyme activity while increasing N and P-cycling enzyme and oxidase activities. Biochar combined with N addition reduced SOC mineralization rate and metabolic quotient (qCO2) by 10.2-22.0% and 6.85-30.4%, respectively, across 15-35 °C and the temperature sensitivity (Q10) by 0.96-4.70%, except for the N1C2 at 25-35 °C. Apparent changes in bacterial alpha diversity and community structures were observed among treatments. Besides, biochar mixed with N application significantly enhanced the relative abundance of Proteobacteria and decreased Acidobacteria, while did not result in significant differences in fungal diversity and community composition. Redundancy analysis indicated that the microbial community composition shifts induced by the interaction between N and biochar were attributed to the changes in soil chemical properties, such as pH and SOC. Overall, the combination of biochar and N fertilizer is recommended to improve SOC sequestration potential and regulate bacterial community diversity and composition in vegetable field for sustainable intensification.


Assuntos
Microbiota , Solo , Bactérias , Carbono/análise , Sequestro de Carbono , Carvão Vegetal/química , Solo/química , Microbiologia do Solo , Temperatura , Verduras
10.
Acta Radiol ; 62(6): 776-783, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32660318

RESUMO

BACKGROUND: Several neuroimaging studies demonstrated that optic neuritis (ON) leads to functional and anatomical architecture changes in the brain. The alterations of interhemispheric functional connectivity (IFC) in patients with AQP4-ON and myelin oligodendrocyte glycoprotein (MOG)-ON are not well understood. PURPOSE: To investigate the differential patterns of VMHC in patients with AQP4-ON and MOG-ON. MATERIAL AND METHODS: Twenty-one patients with AQP4-ON, 11 patients with MOG-ON, and 34 healthy controls underwent resting-state MRI scans. One-way ANOVA was used to identify regions in which the zVMHC differed among the three groups. Post hoc two-sample t-tests were then conducted to compare zVMHC values between pairs of groups. Pearson correlation analysis was conducted to reveal relationships between mean zVMHC values and clinical variables in the AQP4-ON and MOG-ON groups. RESULTS: The results revealed significant differences in zVMHC values in the PreCG among the three groups. Compared to the control group: the AQP4-ON group showed significantly lower VMHC values in the superior temporal gyrus, inferior frontal gyrus, and PreCG; and the MOG-ON group showed significantly higher zVMHC values in the PostCG. Compared to the AQP4-ON group, the MOG-ON group showed significantly lower zVMHC values in the PreCG/PostCG (voxel-level P<0.01, GRF correction, cluster-level P<0.05). CONCLUSION: Patients with AQP4-ON and those with MOG-ON showed abnormal VMHC in the motor cortices, sensorimotor cortices, and frontal lobe, possibly indicating impaired sensorimotor function in patients with ON. Moreover, differential patterns of VMHC in patients with AQP4-ON, compared to patients with MOG-ON, might serve as a clinical indicator for classification of ON.


Assuntos
Aquaporina 4/imunologia , Imageamento por Ressonância Magnética/métodos , Glicoproteína Mielina-Oligodendrócito/imunologia , Neurite Óptica/diagnóstico por imagem , Neurite Óptica/imunologia , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Nervo Óptico/diagnóstico por imagem , Nervo Óptico/imunologia
11.
J Cell Mol Med ; 24(23): 13984-13990, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33155413

RESUMO

Mesenchymal stroma/stem-like cells (MSCs) have antitumour activity, and MSC-derived exosomes play a role in the growth, metastasis and invasion of tumour cells. Additionally, glycoprotein A repetition predominant (GARP) promotes oncogenesis in breast cancer. Therefore, GARP is speculated to be a target gene for cancer therapy. We aimed to explore the therapy role of MSC-derived exosomes targeting GARP in mouse colon cancer cell MC38. We successfully established a GARP knockdown system using three kinds of siRNA-GARP in MSC cells. Exosomes were isolated from MSC and siGARP-MSC cells, and verified by the exosome surface protein markers CD9, CD63 and CD81. GARP expression was significantly decreased in siGARP-MSC exosomes compared with that of MSC exosomes. We found that siGARP-MSC exosomes inhibited cell proliferation, migration and invasion of MC38 cells, using CCK-8, colony formation, wound-healing and Transwell invasion assays. Furthermore, siGARP-MSC exosomes impeded IL-6 secretion and partly inactivated JAK1/STAT3 pathway, measured using ELISA and RT-qPCR. In conclusion, MSC-derived exosomes targeting GARP are a potential strategy for cancer therapy.


Assuntos
Exossomos/metabolismo , Proteínas de Membrana/genética , Células-Tronco Mesenquimais/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Neoplasias do Colo , Técnicas de Silenciamento de Genes , Imuno-Histoquímica , Interleucina-6/metabolismo , Janus Quinase 1/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , MicroRNAs/genética , Interferência de RNA , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
12.
Phys Chem Chem Phys ; 22(14): 7365-7373, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32211620

RESUMO

PdSe2 is a unique layered two-dimensional (2D) material with pentagonal structural motif and anisotropic properties. In addition, its strong interlayer interaction leads to new 2D form of the exfoliated monolayer, that is, Pd2Se3. Despite the increasing interest in these emerging 2D materials, the landscape of the native point defects, as a fundamental materials property, has not been revealed. In this work, we systematically investigate different types of defects in mono- and bi-layer PdSe2 and monolayer Pd2Se3. In contrast to the common expectation, Se vacancy is not the readily formed defect. Instead, Se-excess defects, such as SePd antisite and Se interstitial, are more likely to form over a majority of the allowed range of the atomic chemical potentials. Se-deficiency defect, Pd interstitial, is able to form under the Se-poor condition in bilayer PdSe2. The defect-mediated interlayer fusion model in the formation of monolayer Pd2Se3 from bilayer PdSe2 is reformulated. These dominant defects are found to stay in the neutral charge state, partly explaining the ambipolar behavior of the PdSe2 transistors. Finally, the stacked and lateral contacts between these few-layer semiconductors and the native Pd17Se15 metal are also studied. All these interfaces show p-type contact properties. This work reveals the important materials properties of few-layer PdSe2 and Pd2Se3 for the better development of new functional devices.

13.
BMC Plant Biol ; 19(1): 534, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31795938

RESUMO

BACKGROUND: Flowering is a key process in the life cycle of plants. The transition from vegetative to reproductive growth is thus under sophisticated regulation by endogenous and environmental signals. The plant-specific Teosinte Branched 1/Cycloidea/Proliferating Cell Factors (TCP) family transcription factors are involved in many biological processes, but their roles in regulating flowering have not been totally elucidated. RESULTS: We explored the role of Arabidopsis TCP8 in plant development and, especially, in flowering control. Overexpression of TCP8 significantly delayed flowering under both long-day and short-day conditions and dominant repression by TCP8 led to various growth defects. The upregulation of TCP8 led to more accumulated mRNA level of FLOWERING LOCUS C (FLC), a central floral repressor of Arabidopsis. TCP8 functions in an FLC-dependent manner, as TCP8 overexpression in the flc-6 loss-of-function mutant failed to delay flowering. The vernalization treatment could reverse the late flowering phenotype caused by TCP8 overexpression. CONCLUSIONS: Our results provide evidence for a role of TCP8 in flowering control and add to our knowledge of the molecular basis of TCP8 function.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Proteínas de Domínio MADS/genética , Fatores de Transcrição/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Flores/genética , Proteínas de Domínio MADS/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo
14.
Molecules ; 24(20)2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31658635

RESUMO

Natural products are a precious source of promising leads for the development of novel cancer therapeutics. Recently, triterpenoids in Alismatis rhizoma has been widely demonstrated for their anti-cancer activities in cancer cells. In this study, we examined the inhibitory effects of alisol A in human breast cancer cells. We demonstrated that alisol A exhibited significant anti-proliferative effects in MDA-MB-231 cells and this response was related to autophagy induction. Alisol A-induced autophagy was supported by the triggered autophagosome formation and increased LC3-II levels. Interestingly, autophagy inhibitor 3-MA significantly reversed the cytotoxic effects induced by alisol A. Meanwhile, alisol A-induced autophagy was significantly inhibited by 3-MA in MDA-MB-231 cells. Cell cycle analysis revealed that alisol A arrested the cell cycle at G0/G1 phase. The expression level of cell cycle regulatory proteins cyclin D1 was significantly down regulated. In addition, the suppression of NF-κB and PI3K/Akt/mTOR pathways in MDA-MB-231 cells was observed. Furthermore, alisol A significantly suppressed the migration and invasion of MDA-MB-231 cells by inhibiting the expression levels of MMP-2 and MMP-9. Taken together, our results demonstrated that alisol A could inhibit the proliferation and metastasis of MDA-MB-231 cells. It could be a promising agent for breast cancer therapy.


Assuntos
Neoplasias da Mama/metabolismo , Movimento Celular/efeitos dos fármacos , Colestenonas/farmacologia , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Morte Celular Autofágica/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Invasividade Neoplásica , Transdução de Sinais/efeitos dos fármacos
15.
Neurosci Bull ; 40(9): 1287-1298, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38807019

RESUMO

Alcohol abuse induces various neurological disorders including motor learning deficits, possibly by affecting neuronal and astrocytic activity. Physical exercise is one effective approach to remediate synaptic loss and motor deficits as shown by our previous works. In this study, we unrevealed the role of exercise training in the recovery of cortical neuronal and astrocytic functions. Using a chronic alcohol injection mouse model, we found the hyperreactivity of astrocytes along with dendritic spine loss plus lower neuronal activity in the primary motor cortex. Persistent treadmill exercise training, on the other hand, improved neural spine formation and inhibited reactive astrocytes, alleviating motor learning deficits induced by alcohol exposure. These data collectively support the potency of endurance exercise in the rehabilitation of motor functions under alcohol abuse.


Assuntos
Astrócitos , Etanol , Camundongos Endogâmicos C57BL , Córtex Motor , Neurônios , Animais , Masculino , Etanol/toxicidade , Córtex Motor/fisiopatologia , Neurônios/fisiologia , Condicionamento Físico Animal/fisiologia , Condicionamento Físico Animal/métodos , Camundongos , Modelos Animais de Doenças , Deficiências da Aprendizagem/etiologia , Espinhas Dendríticas/patologia , Alcoolismo/fisiopatologia , Alcoolismo/terapia , Aprendizagem/fisiologia , Aprendizagem/efeitos dos fármacos
16.
Toxics ; 12(2)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38393241

RESUMO

Chiral pesticides exhibit enantioselective differences in processes such as biological absorption, metabolism, and toxic effects. Organisms have different physiological characteristics at different developmental stages. Therefore, conducting enantiomeric toxicity studies at different developmental stages of organisms can help deepen the understanding of the ecological effects of chiral pesticides. This study focused on trans-tetramethrin (Tet) and investigated the enantioselectivity in bioconcentration, developmental toxicity, estrogenic effects, and immunotoxicity of Tet's racemate ((±)-Tet) and its two enantiomers ((+)-Tet and (-)-Tet) in three developmental stages of zebrafish: embryos, yolk sac larvae, and juveniles. The results showed that Tet exhibited different enantioselectivity in lethal, bioconcentration, and teratogenic effects on zebrafish at different developmental stages. The LC50 value was (+)-Tet > (±)-Tet > (-)-Tet, with embryos being the most sensitive, followed by juveniles and yolk sac larvae. The enantioselective bioconcentration was (±)-Tet > (+)-Tet > (-)-Tet, and the bioconcentration effect was greater in embryos than that in yolk sac larvae and juveniles. Developmental toxicity indicated that (+)-Tet and (±)-Tet had higher teratogenic effects on yolk sac larvae than on embryos. Tet exhibited different enantioselective effects on the expression of zebrafish estrogen-related genes and innate immune-related genes at different developmental stages. These results will contribute to a more comprehensive assessment of the aquatic toxicity and environmental risks of chiral pesticides.

17.
Br J Ophthalmol ; 108(9): 1313-1317, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-38237954

RESUMO

PURPOSE: To describe the pattern of MRI changes in the pregeniculate visual pathway in Leber hereditary optic neuropathy (LHON). METHOD: This retrospective observational study enrolled 60 patients with LHON between January 2015 and December 2021. The abnormal MRI features seen in the pregeniculate visual pathway were investigated, and then correlated with the causative mitochondrial DNA (mtDNA) mutation, the distribution of the MRI lesions and the duration of vision loss. RESULT: The cohort included 48 (80%) males and 53 (88%) had bilateral vision loss. The median age of onset was 17.0 years (range 4.0-58.0). 28 (47%) patients had the m.11778G>A mutation. 34 (57%) patients had T2 hyperintensity (HS) in the pregeniculate visual pathway and 13 (22%) patients with chiasmal enlargement. 20 patients (71%) carrying the m.11778G>A mutation had T2 HS, significantly more than the 14 patients (44%) with T2 HS in the other LHON mutation groups (p=0.039). Furthermore, significantly more patients in the m.11778G>A group (16 patients (57%)) had T2 HS in optic chiasm (OCh)/optic tract (OTr) than the other LHON mutation groups (7 patients (22%), p=0.005). Optic chiasmal enlargement was more common in patients with vision loss duration <3 months compared with those ≥3 months (p=0.028). CONCLUSION: T2 HS in the pregeniculate visual pathway is a frequent finding in LHON. Signal changes in the OCh/OTr and chiasmal enlargement, in particular within the first 3 months of visual loss, were more commonly seen in patients carrying the m.11778G>A mtDNA mutation, which may be of diagnostic significance.


Assuntos
DNA Mitocondrial , Imageamento por Ressonância Magnética , Atrofia Óptica Hereditária de Leber , Quiasma Óptico , Vias Visuais , Humanos , Atrofia Óptica Hereditária de Leber/genética , Atrofia Óptica Hereditária de Leber/fisiopatologia , Atrofia Óptica Hereditária de Leber/diagnóstico , Masculino , Quiasma Óptico/patologia , Quiasma Óptico/diagnóstico por imagem , Estudos Retrospectivos , Feminino , Adulto , Vias Visuais/patologia , Vias Visuais/diagnóstico por imagem , Vias Visuais/fisiopatologia , Pessoa de Meia-Idade , Adolescente , Adulto Jovem , Criança , DNA Mitocondrial/genética , Pré-Escolar , Acuidade Visual/fisiologia , Neuroimagem , Mutação
18.
Front Plant Sci ; 15: 1347842, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38328701

RESUMO

FHY3 and its homologous protein FAR1 are the founding members of FRS family. They exhibited diverse and powerful physiological functions during evolution, and participated in the response to multiple abiotic stresses. FRF genes are considered to be truncated FRS family proteins. They competed with FRS for DNA binding sites to regulate gene expression. However, only few studies are available on FRF genes in plants participating in the regulation of abiotic stress. With wide adaptability and high stress-resistance, barley is an excellent candidate for the identification of stress-resistance-related genes. In this study, 22 HvFRFs were detected in barley using bioinformatic analysis from whole genome. According to evolution and conserved motif analysis, the 22 HvFRFs could be divided into subfamilies I and II. Most promoters of subfamily I members contained abscisic acid and methyl jasmonate response elements; however, a large number promoters of subfamily II contained gibberellin and salicylic acid response elements. HvFRF9, one of the members of subfamily II, exhibited a expression advantage in different tissues, and it was most significantly upregulated under drought stress. In-situ PCR revealed that HvFRF9 is mainly expressed in the root epidermal cells, as well as xylem and phloem of roots and leaves, indicating that HvFRF9 may be related to absorption and transportation of water and nutrients. The results of subcellular localization indicated that HvFRF9 was mainly expressed in the nuclei of tobacco epidermal cells and protoplast of arabidopsis. Further, transgenic arabidopsis plants with HvFRF9 overexpression were generated to verify the role of HvFRF9 in drought resistance. Under drought stress, leaf chlorosis and wilting, MDA and O2 - contents were significantly lower, meanwhile, fresh weight, root length, PRO content, and SOD, CAT and POD activities were significantly higher in HvFRF9-overexpressing arabidopsis plants than in wild-type plants. Therefore, overexpression of HvFRF9 could significantly enhance the drought resistance in arabidopsis. These results suggested that HvFRF9 may play a key role in drought resistance in barley by increasing the absorption and transportation of water and the activity of antioxidant enzymes. This study provided a theoretical basis for drought resistance in barley and provided new genes for drought resistance breeding.

19.
Nat Commun ; 15(1): 5605, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961083

RESUMO

Because of their large surface areas, nanotubes and nanowires demonstrate exquisite mechanical coupling to their surroundings, promising advanced sensors and nanomechanical devices. However, this environmental sensitivity has resulted in several ambiguous observations of vibrational coupling across various experiments. Herein, we demonstrate a temperature-dependent Radial Breathing Mode (RBM) frequency in free-standing, electron-diffraction-assigned Double-Walled Carbon Nanotubes (DWNTs) that shows an unexpected and thermally reversible frequency downshift of 10 to 15%, for systems isolated in vacuum. An analysis based on a harmonic oscillator model assigns the distinctive frequency cusp, produced over 93 scans of 3 distinct DWNTs, along with the hyperbolic trajectory, to a reversible increase in damping from graphitic ribbons on the exterior surface. Strain-dependent coupling from self-tensioned, suspended DWNTs maintains the ratio of spring-to-damping frequencies, producing a stable saturation of RBM in the low-tension limit. In contrast, when the interior of DWNTs is subjected to a water-filling process, the RBM thermal trajectory is altered to that of a Langmuir isobar and elliptical trajectories, allowing measurement of the enthalpy of confined fluid phase change. These mechanisms and quantitative theory provide new insights into the environmental coupling of nanomechanical systems and the implications for devices and nanofluidic conduits.

20.
Expert Rev Hematol ; 16(11): 849-860, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37819160

RESUMO

INTRODUCTION: This study aimed to identify the factors affecting the quality of life (QOL) and functional status of patients with MDS. AREAS COVERED: We reviewed the literature published in PUBMED over the past 30 years and searched for keywords such as 'quality of life' and 'myelodysplastic syndromes'. By observing the influence of their symptoms, the possibility of improving patients' QOL was considered by improving these related factors. Concurrently, the effects of related clinical treatments based on the unique disease characteristics of MDS on the patients' QOL were examined, and lifestyle factors were considered in clinical practice, providing an important path to improve the QOL and functional status of patients with MDS. EXPERT OPINION: This review summarized several areas that can improve the quality of survival of MDS patients and discusses them in depth. Although the clinical benefits may be minimal, we still hope to improve patients' daily life outcomes and enhance their quality of life at minimal cost. Also, we hope more researchers will focus on this area in the future to find more factors that may exist to supplement the limitations of these understanding and thinking, and to provide assistance in clinical work.


Assuntos
Síndromes Mielodisplásicas , Qualidade de Vida , Humanos , Síndromes Mielodisplásicas/terapia
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