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1.
BMC Plant Biol ; 24(1): 980, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39420293

RESUMO

BACKGROUND: Drought stress is a significant abiotic stressor that hinders growth, development, and crop yield in soybeans. Strigolactones (SLs) positively regulate plant resistance to drought stress. However, the impact of foliar application of SLs having different concentrations on soybean growth and metabolic pathways related to osmoregulation remains unknown. Therefore, to clarify the impact of SLs on soybean root growth and cellular osmoregulation under drought stress, we initially identified optimal concentrations and assessed key leaf and root indices. Furthermore, we conducted transcriptomic and metabolic analyses to identify differential metabolites and up-regulated genes. RESULTS: The results demonstrated that drought stress had a significant impact on soybean biomass, root length, root surface area, water content and photosynthetic parameters. However, when SLs were applied through foliar application at appropriate concentrations, the accumulation of ABA and soluble protein increased, which enhanced drought tolerance of soybean seedlings by regulating osmotic balance, protecting membrane integrity, photosynthesis and activating ROS scavenging system. This also led to an increase in soybean root length, lateral root number and root surface area. Furthermore, the effects of different concentrations of SLs on soybean leaves and roots were found to be time-sensitive. However, the application of 0.5 µM SLs had the greatest beneficial impact on soybean growth and root morphogenesis under drought stress. A total of 368 differential metabolites were screened in drought and drought plus SLs treatments. The up-regulated genes were mainly involved in nitrogen compound utilization, and the down-regulated metabolic pathways were mainly involved in maintaining cellular osmoregulation and antioxidant defenses. CONCLUSIONS: SLs enhance osmoregulation in soybean plants under drought stress by regulating key metabolic pathways including Arachidonic acid metabolism, Glycerophospholipid metabolism, Linoleic acid metabolism, and Flavone and flavonol biosynthesis. This study contributes to the theoretical understanding of improving soybean adaptability and survival in response to drought stress.


Assuntos
Antioxidantes , Secas , Glycine max , Lactonas , Osmorregulação , Glycine max/efeitos dos fármacos , Glycine max/fisiologia , Glycine max/genética , Glycine max/metabolismo , Antioxidantes/metabolismo , Lactonas/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Folhas de Planta/metabolismo , Redes e Vias Metabólicas/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/fisiologia , Raízes de Plantas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos
2.
Small ; 20(31): e2308690, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38470201

RESUMO

Traditional surface-enhanced Raman scattering (SERS) sensors rely heavily on the use of plasmonic noble metals, which have limitations due to their high cost and lack of physical and chemical stability. Hence, it is imperative to explore new materials as SERS platforms that can withstand high temperatures and harsh conditions. In this study, the SERS effect of molybdenum boride ceramic powders is presented with an enhancement factor of 5 orders, which is comparable to conventional noble metal substrates. The molybdenum boride powders synthesized through liquid-phase precursor and carbothermal reduction have ß-MoB, MoB2, and Mo2B5 phases. Among these phases, ß-MoB demonstrates the most significant SERS activity, with a detection limit for rhodamine 6G (R6G) molecules of 10-9 m. The impressive SERS enhancement can be attributed to strong molecule interactions and prominent charge interactions between R6G and the various phases of molybdenum boride, as supported by theoretical calculations. Additionally, Raman measurements show that the SERS activity remains intact after exposure to high temperature, strong acids, and alkalis. This research introduces a novel molybdenum boride all-ceramic SERS platform capable of functioning in harsh conditions, thereby showing the promising of boride ultrahigh-temperature ceramics for detection applications in extreme environments.

3.
Small ; 20(36): e2401159, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38716681

RESUMO

Defects can introduce atomic structural modulation and tailor performance of materials. Herein, it demonstrates that semiconductor WO3 with inert electrocatalytic behavior can be activated through defect-induced tensile strains. Structural characterizations reveal that when simply treated in Ar/H2 atmosphere, oxygen vacancies will generate in WO3 and cause defective structures. Stacking faults are found in defects, thus modulating electronic structure and transforming electrocatalytic-inert WO3 into highly active electrocatalysts. Density functional theory (DFT) calculations are performed to calculate *H adsorption energies on various WOx surfaces, revealing the oxygen vacancy composition and strain predicted to optimize the catalytic activity of hydrogen evolution reaction (HER). Such defective tungsten oxides can be integrated into commercial proton exchange membrane (PEM) electrolyser with comparable performance toward Pt-based PEM. This work demonstrates defective metal oxides as promising non-noble metal catalysts for commercial PEM green-hydrogen generation.

4.
Langmuir ; 40(40): 21067-21076, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39329510

RESUMO

Understanding the interlayer interaction between 2D layered structures is critical for the construction of various micro- and nanoscale functional devices. However, both the normal and the tangential interlayer interactions between 2D layered materials have rarely been studied simultaneously. In this work, an immersion and lift-up method is proposed to wrap a layer of graphene flakes onto a plasma-pretreated atomic force microscopy (AFM) nanoprobe for the measurements of interaction forces by AFM. The normal interactions (adhesion force and adhesion energy) and tangential interactions (friction force) between two different probes (Pt-coated probe and graphene-wrapped probe) and two different 2D graphene materials [graphene and graphene oxide (GO)] were systematically measured, respectively. The adhesion energies of Pt-GO, Pt-graphene, graphene-GO, and graphene-graphene were measured to be 0.72 ± 0.05, 0.41 ± 0.03, 0.19 ± 0.02, and 0.10 ± 0.02 J m-2, respectively. The graphene-graphene contact pair showed the lowest adhesion force (5.57 ± 1.03 nN) and adhesion energy (0.10 ± 0.02 J m-2), which was attributed to the strong covalent bonds and charge density distribution. The friction coefficients of Pt-GO, graphene-GO, Pt-graphene, and graphene-graphene were determined to be 0.38, 0.14, 0.054, and 0.013. The graphene-graphene tribo-pair exhibited a superlow friction state for a long time, which was attributed to incommensurate contact and weak van der Waals interactions. These findings provide a technical route to reveal the interlayer interactions of various 2D layered materials, which can be widely applied in microelectromechanical systems.

5.
Langmuir ; 40(1): 950-959, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38110298

RESUMO

Frost formation and accumulation can have catastrophic effects on a wide range of industrial activities. Hence, a dual-scale surface with a stable Cassie-Baxter state is developed to mitigate the frosting problem by utilizing direct laser interference lithography assisted with hydrothermal treatment. The high Laplace pressure tolerance under the evaporation stimulus and prolonged Cassie-Baxter state maintenance under the condensation stimulus demonstrate the stable Cassie-Baxter state. The dual-scale surface exhibits a lengthy frost-delaying time of up to 5277 s at -7 °C due to the stable Cassie-Baxter state. The self-removal of frost is achieved by promoting the mobility of frost melts driven by the released interfacial energy. In addition, the dense flocculent frost layer is observed on the single-scale micro surface, whereas the sparse pearl-shaped frost layer with many voids is obtained on the dual-scale surface. This work will aid in understanding the frosting process on various-scale superhydrophobic surfaces and in the design of antifrosting surfaces.

6.
Phys Chem Chem Phys ; 26(10): 7988-8012, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38380525

RESUMO

Artificial materials, characterized by their distinctive properties and customized functionalities, occupy a central role in a wide range of applications including electronics, spintronics, optoelectronics, catalysis, and energy storage. The emergence of atomically thin two-dimensional (2D) materials has driven the creation of artificial heterostructures, harnessing the potential of combining various 2D building blocks with complementary properties through the art of stacking engineering. The promising outcomes achieved for heterostructures have spurred an inquisitive exploration of homostructures, where identical 2D layers are precisely stacked. This perspective primarily focuses on the field of stacking engineering within layered homostructures, where precise control over translational or rotational degrees of freedom between vertically stacked planes or layers is paramount. In particular, we provide an overview of recent advancements in the stacking engineering applied to 2D homostructures. Additionally, we will shed light on research endeavors venturing into three-dimensional (3D) structures, which allow us to proactively address the limitations associated with artificial 2D homostructures. We anticipate that the breakthroughs in stacking engineering in 3D materials will provide valuable insights into the mechanisms governing stacking effects. Such advancements have the potential to unlock the full capability of artificial layered homostructures, propelling the future development of materials, physics, and device applications.

7.
Biol Pharm Bull ; 47(5): 978-987, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38631865

RESUMO

Nonalcoholic steatohepatitis (NASH) is a subtype of nonalcoholic fatty liver disease (NAFLD) characterized by hepatic steatosis and evidence of hepatocyte injury (ballooning) and inflammation, with or without liver fibrosis. In this study, after 12 weeks of induction, the mice were treated with emodin succinyl ethyl ester (ESEE) for four weeks at doses of 10/30/90 mg/kg/d. The blood analysis of experimental endpoints showed that ESEE exhibited significant therapeutic effects on the progression of disorders of glycolipid metabolism and the induced liver injury in the model animals. Histopathological diagnosis of the liver and total triglyceride measurements revealed that ESEE had a significant therapeutic effect on the histopathological features of nonalcoholic fatty liver disease/hepatitis, such as cellular steatosis and activation of intrahepatic inflammation. Additionally, ESEE was able to improve hepatocyte fat deposition, steatosis, and the course of intrahepatic inflammatory activity. Furthermore, it showed some inhibitory effect on liver fibrosis in the model animals. In summary, this study confirms the therapeutic effects of ESEE on the NAFLD/NASH model in C57BL/6J mice induced by a high-fat, high cholesterol, and fructose diet. These effects were observed through improvements in liver function, inhibition of fibrosis, and inflammatory responses. Changes in blood glucose levels, blood lipid metabolism, liver histopathological staining, liver fibrosis staining, and related pathological scores further supported the therapeutic effects of ESEE. Therefore, this study has important implications for the exploration of novel drugs for nonalcoholic fatty liver disease.


Assuntos
Dieta Hiperlipídica , Emodina , Frutose , Fígado , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/etiologia , Masculino , Emodina/farmacologia , Emodina/uso terapêutico , Emodina/análogos & derivados , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/metabolismo , Dieta Hiperlipídica/efeitos adversos , Camundongos , Triglicerídeos/sangue , Colesterol/sangue , Modelos Animais de Doenças , Glicemia/efeitos dos fármacos
8.
J Sep Sci ; 47(5): e2300922, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38471974

RESUMO

Qi-Wei-Tong-Bi oral liquid (QWTB), a famous Chinese medicine preparation composed of seven crude drugs has a good therapeutic effect on rheumatoid arthritis and is widely used in China. However, its chemical composition and quality control have not been comprehensively and systematically investigated. In this study, high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was employed for its chemical profiling. As a result, 100 components were chemically characterized. Additionally, high-performance liquid chromatography coupled with a quadrupole linear ion trap mass spectrometry method was developed to simultaneously quantify nine bioactive components (hyperoside, ononin, quercetin, sinomenine, magnoflorine, gallic acid, protocatechuic acid, monotropein, and cyclo-(Pro-Tyr)) in multiple-reaction monitoring mode. After successful validation in terms of linearity, precision, repeatability, and recovery, the assay method was applied for the determination of 10 batches of QWTB. The results showed that QWTB was enriched in sinomenine and magnoflorine with the highest amount up to hundreds or even thousands of µg/mL, while quercetin, ononin, cyclo-(Pro-Tyr), and hyperoside were much lower with the lowest content below 10 µg/mL. This study work would help to reveal the chemical profiling and provide a valuable and reliable approach for quality evaluation and even pharmacodynamic material basis studies of QWTB.


Assuntos
Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Flavonoides/análise , Espectrometria de Massa com Cromatografia Líquida , Quercetina/análise , Espectrometria de Massas em Tandem/métodos
9.
Appl Opt ; 63(5): 1394-1401, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38437320

RESUMO

Broadband antireflection (AR) is highly significant in a wide range of optical applications, and using a gold (Au) micropattern presents a viable method for controlling the behavior of light propagation. This study investigates a novel, to the best of our knowledge, methodology to achieve broadband AR properties in Au micropatterns. It employed the three-dimensional finite-difference time-domain (FDTD) method to simulate and optimize the design of micropatterns. In contrast, the fabrication of Au micropatterns was carried out using two-beam laser interference lithography (LIL). The fabricated Au micropatterns were characterized by a scanning electron microscope (SEM) and spectroscope to validate their antireflection and transmission properties and evaluate their performance at various wavelengths. The optimized Au micropatterns had a high transmittance rating of 96.2%. In addition, the device exhibits a broad-spectrum antireflective property, covering wavelengths ranging from 400 to 1100 nm. The simulation data and experimentally derived results show comparable patterns. These structures can potentially be employed in many optical devices, such as solar cells and photodetectors, whereby achieving optimal device performance reduced reflection and enhanced light absorption.

10.
BMC Public Health ; 24(1): 1429, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807089

RESUMO

OBJECTIVES: The purpose of our study is to further understanding of the depression symptoms of HIV/AIDS patients in Guilin, Guangxi via exploring whether there is a mediating effect of sleep quality on medical-social support and depression symptoms and therefore provide a theoretical basis for application of medical-social support to alleviate depression symptoms of HIV/AIDS patients. METHODS: A convenience sampling method was used to select 200 HIV/AIDS patients for the study. Depression symptoms, sleep quality, and medical-social support of the study participants were investigated using The Center for Epidemiological Studies Depression Scale (CES-D), The Pittsburg Sleep Quality Index (PSQI), and The Medical Outcomes Study Social Support Survey (MOS-SSS), respectively. Predictors of depression symptoms were explored by multiple linear regression, and Pearson correlation was used to analyze the relationship between sleep quality, medical-social support, and depression symptoms. Mediating effect analysis was performed by nonparametric Bootstrap test. RESULTS: In this study, the incidence of depression symptoms was 54.4%. Multiple linear regression analysis showed that leanness (ß = 0.161, P = 0.008), obesity (ß = 0.186, P = 0.002), sleep quality score > 7 (ß = 0.331, P < 0.001), and medical-social support score > 56 (ß = -0.247, P < 0.001) could influence depression symptoms of HIV and Pearson's correlation analysis demonstrated that there was a two-way correlation between sleep quality, medical social support and depression symptoms (P < 0.05). In addition, Bootstrap tests showed that medical-social support might affect depression symptoms not only directly but also indirectly through the mediating effect of sleep quality with the direct and mediating effects accounting for 77.25% and 22.75% of the total effect, respectively. CONCLUSION: The prevalence of depression symptoms is high among HIV/AIDS patients in Guilin City. The depressive symptoms of PLWHs(people living with HIV) are related to their sleep quality and medical-social support, and sleep quality partially mediates the relationship between medical-social support and depression symptoms. Therefore, interventions to improve sleep quality and medical-social support have the potential to allay the depression symptoms of HIV/AIDS patients.


Assuntos
Depressão , Infecções por HIV , Qualidade do Sono , Apoio Social , Humanos , Masculino , Feminino , Depressão/epidemiologia , Adulto , Infecções por HIV/psicologia , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , China/epidemiologia , Pessoa de Meia-Idade , Síndrome da Imunodeficiência Adquirida/psicologia , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/epidemiologia , Estudos Transversais , Inquéritos e Questionários , Adulto Jovem
11.
World J Surg Oncol ; 22(1): 90, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600491

RESUMO

OBJECTIVES: This study aims to gather and analyze the anatomical characteristics of the posterior gastric artery (PGA), investigate the presence and metastasis of lymph nodes around the PGA in patients with gastric cancer. Additionally, the study aims to analyze the relationship between the PGA and its surrounding lymph nodes and the clinicopathological features of patients with gastric cancer. METHODS: This study consisted of a cross-sectional analysis of data from 52 patients with gastric cancer who underwent total or proximal gastrectomy at the Department of Gastrointestinal Surgery, First Affiliated Hospital of Dalian Medical University, between January 2020 and November 2022. Intraoperative exploration was performed to determine the presence of the PGA, and patients with the PGA were assessed for relevant anatomical characteristics, including the length of the PGA and the distance from the root of the PGA to the celiac trunk. Dissection of lymph nodes around the PGA was also performed. Statistical methods were employed to describe and analyze the data regarding the presence of the PGA, as well as the presence and metastasis of the lymph nodes around the PGA. Additionally, the study identified clinicopathological factors associated with these conditions. RESULTS: The PGA was identified in 39 (75.0%) out of 52 patients with gastric cancer, exhibiting a mean PGA length of 3.5 ± 0.8 cm and a mean distance from the root of the PGA to the celiac trunk of 6.7 ± 1.7 cm. Among the 39 patients who underwent dissection of lymph nodes around the PGA, 36 lymph nodes around the PGA were detected in 20 patients. Analysis of factors associated with the presence of lymph nodes around the PGA revealed a significant correlation with the macroscopic type of the tumor and the total number of dissected lymph nodes (P = 0.007 and P = 0.022, respectively), with a larger number of total dissected lymph nodes being an independent factor (OR = 1.105, 95%CI: 1.019-1.199, P = 0.016). Furthermore, analysis of risk factors for metastasis of the lymph nodes around the PGA demonstrated that the total number of metastatic lymph nodes, No.3 lymph node metastasis, and No.11 lymph node metastasis were associated with metastasis of the lymph nodes around the PGA (P = 0.043, P = 0.028, and P = 0.020, respectively). CONCLUSION: The PGA exhibits a high incidence. It is essential to carefully identify the PGA during procedures involving the PGA and consider appropriate preservation or disconnection of this vessel. The presence of lymph nodes around the PGA is not an isolated occurrence. Gastric cancer can result in metastasis of the lymph nodes around the PGA. Although the overall risk of metastasis of the lymph nodes around the PGA is low in patients with gastric cancer, it increases in the presence of conditions such as No.3 lymph node metastasis, No.11 lymph node metastasis, advanced tumor stage, and extensive metastases in other regional lymph nodes.


Assuntos
Excisão de Linfonodo , Neoplasias Gástricas , Humanos , Excisão de Linfonodo/métodos , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Metástase Linfática/patologia , Estudos Transversais , Artéria Gástrica/patologia , Linfonodos/cirurgia , Linfonodos/patologia , Gastrectomia , Estudos Retrospectivos
12.
World J Surg Oncol ; 22(1): 87, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582834

RESUMO

BACKGROUND: To investigate the short-term and long-term outcomes of preserving the celiac branch of the vagus nerve during laparoscopic distal gastrectomy. METHODS: A total of 149 patients with prospective diagnosis of gastric cancer who underwent laparoscopic-assisted distal gastrectomy (LADG) combined with Billroth-II anastomosis and D2 lymph node dissection between 2017 and 2018 were retrospectively analyzed. The patients were divided into the preserved LADG group (P-LADG, n = 56) and the resected LADG group (R-LADG, n = 93) according to whether the vagus nerve celiac branch was preserved. We selected 56 patients (P-LADG, n = 56) with preservation of the celiac branch of the vagus nerve and 56 patients (R-LADG, n = 56) with removal of the celiac branch of the vagus nerve by propensity-matched score method. Postoperative nutritional status, weight change, short-term and long-term postoperative complications, and gallstone formation were evaluated in both groups at 5 years of postoperative follow-up. The status of residual gastritis and bile reflux was assessed endoscopically at 12 months postoperatively. RESULTS: The incidence of diarrhea at 5 years postoperatively was lower in the P-LADG group than in the R-LADG group (p < 0.05). In the multivariate logistic analysis, the removal of vagus nerve celiac branch was an independent risk factor for the occurrence of postoperative diarrhea (odds ratio = 3.389, 95% confidential interval = 1.143-10.049, p = 0.028). In the multivariate logistic analysis, the removal of vagus nerve celiac branch was an independent risk factor for the occurrence of postoperative diarrhea (odds ratio = 4.371, 95% confidential interval = 1.418-13.479, p = 0.010). CONCLUSIONS: Preservation of the celiac branch of the vagus nerve in LADG reduced the incidence of postoperative diarrhea postoperatively in gastric cancer. TRIAL REGISTRATION: This study was registered with the Ethics Committee of the First Affiliated Hospital of Dalian Medical University in 2014 under the registration number: LCKY2014-04(X).


Assuntos
Laparoscopia , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Estudos de Coortes , Estudos Retrospectivos , Estudos Prospectivos , Incidência , Gastrectomia/efeitos adversos , Gastrectomia/métodos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Nervo Vago/patologia , Nervo Vago/cirurgia , Diarreia/epidemiologia , Diarreia/etiologia , Diarreia/prevenção & controle , Resultado do Tratamento
13.
Proc Natl Acad Sci U S A ; 118(15)2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33833054

RESUMO

Learning and memory are assumed to be supported by mechanisms that involve cholinergic transmission and hippocampal theta. Using G protein-coupled receptor-activation-based acetylcholine sensor (GRABACh3.0) with a fiber-photometric fluorescence readout in mice, we found that cholinergic signaling in the hippocampus increased in parallel with theta/gamma power during walking and REM sleep, while ACh3.0 signal reached a minimum during hippocampal sharp-wave ripples (SPW-R). Unexpectedly, memory performance was impaired in a hippocampus-dependent spontaneous alternation task by selective optogenetic stimulation of medial septal cholinergic neurons when the stimulation was applied in the delay area but not in the central (choice) arm of the maze. Parallel with the decreased performance, optogenetic stimulation decreased the incidence of SPW-Rs. These findings suggest that septo-hippocampal interactions play a task-phase-dependent dual role in the maintenance of memory performance, including not only theta mechanisms but also SPW-Rs.


Assuntos
Neurônios Colinérgicos/fisiologia , Hipocampo/fisiologia , Memória de Curto Prazo , Ritmo Teta , Acetilcolina/metabolismo , Animais , Neurônios Colinérgicos/metabolismo , Hipocampo/citologia , Hipocampo/metabolismo , Camundongos , Optogenética
14.
Proc Natl Acad Sci U S A ; 118(13)2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33753493

RESUMO

Conventional T cell fate and function are determined by coordination between cellular signaling and mitochondrial metabolism. Invariant natural killer T (iNKT) cells are an important subset of "innate-like" T cells that exist in a preactivated effector state, and their dependence on mitochondrial metabolism has not been previously defined genetically or in vivo. Here, we show that mature iNKT cells have reduced mitochondrial respiratory reserve and iNKT cell development was highly sensitive to perturbation of mitochondrial function. Mice with T cell-specific ablation of Rieske iron-sulfur protein (RISP; T-Uqcrfs1-/- ), an essential subunit of mitochondrial complex III, had a dramatic reduction of iNKT cells in the thymus and periphery, but no significant perturbation on the development of conventional T cells. The impaired development observed in T-Uqcrfs1-/- mice stems from a cell-autonomous defect in iNKT cells, resulting in a differentiation block at the early stages of iNKT cell development. Residual iNKT cells in T-Uqcrfs1-/- mice displayed increased apoptosis but retained the ability to proliferate in vivo, suggesting that their bioenergetic and biosynthetic demands were not compromised. However, they exhibited reduced expression of activation markers, decreased T cell receptor (TCR) signaling and impaired responses to TCR and interleukin-15 stimulation. Furthermore, knocking down RISP in mature iNKT cells diminished their cytokine production, correlating with reduced NFATc2 activity. Collectively, our data provide evidence for a critical role of mitochondrial metabolism in iNKT cell development and activation outside of its traditional role in supporting cellular bioenergetic demands.


Assuntos
Metabolismo Energético/fisiologia , Mitocôndrias/metabolismo , Células T Matadoras Naturais/fisiologia , Animais , Antígenos CD1d/metabolismo , Diferenciação Celular , Complexo III da Cadeia de Transporte de Elétrons/deficiência , Complexo III da Cadeia de Transporte de Elétrons/genética , Técnicas de Silenciamento de Genes , Interleucina-15/metabolismo , Proteínas Ferro-Enxofre/genética , Ativação Linfocitária , Camundongos , Camundongos Knockout , Células T Matadoras Naturais/citologia
15.
Sensors (Basel) ; 24(18)2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39338712

RESUMO

Using first-principles theory, this work purposes Ru-doped Janus WSSe (Ru-WSSe) monolayer as a potential gas sensor for detection of three typical gas species (CO, C2H2, and C2H4), in order to evaluate the operation status of the oil-immersed transformers. The Ru-doping behavior on the WSSe surface is analyzed, giving rise to the preferred doping site by the replacement of a Se atom with the formation energy of 0.01 eV. The gas adsorption of three gas species onto the Ru-WSSe monolayer is conducted, and chemisorption is identified for all three gas systems with the adsorption energy following the order: CO (-2.22 eV) > C2H2 (-2.01 eV) > C2H4 (-1.70 eV). Also, the modulated electronic properties and the frontier molecular orbital are investigated to uncover the sensing mechanism of Ru-WSSe monolayer upon three typical gases. Results reveal that the sensing responses of the Ru-WSSe monolayer, based on the variation of energy gap, to CO, C2H2, and C2H4 molecules are calculated to be 1.67 × 106, 2.10 × 105, and 9.61 × 103, respectively. Finally, the impact of the existence of O2 molecule for gas adsorption and sensing is also analyzed to uncover the potential of Ru-WSSe monolayer for practical application in the air atmosphere. The obtained high electrical responses manifest strong potential as a resistive sensor for detection of three gases. The findings hold practical implications for the development of novel gas sensing materials based on Janus WSSe monolayer. We anticipate that our results will inspire further research in this domain, particularly for applications in electrical engineering where the reliable detection of fault gases is paramount for maintaining the integrity and safety of power systems.

16.
J Fish Biol ; 104(2): 433-449, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36879537

RESUMO

Two new species of Leptobotia are here described as L. rotundilobus from the Xin'an-Jiang of the upper Qiantang-Jiang basin in both Anhui and Zhejiang Provinces and the Cao'e-Jiang in Zhejiang Province, and L. paucipinna from the Qing-Jiang of the middle Chang-Jiang basin in Hubei Province, South China. Both have a plain brown body as found in L. bellacauda Bohlen & Slechtová, 2016, L. microphthalma Fu & Ye, 1983, L. posterodorsalis Chen & Lan, 1992 and L. tientainensis (Wu, 1930). The two new species are distinct from these species in vertebral counts, further from L. posterodorsalis in vent placement and further from the other three species in pectoral-fin length. Both differ in caudal-fin coloration and shape, and dorsal-fin location and coloration, and also in internal morphology. Their validity is confirmed by their own monophyly recovered in a phylogenetic analysis based on the mitochondrial cyt b and COI genes.


Assuntos
Cipriniformes , Animais , Cipriniformes/anatomia & histologia , Filogenia , China , Rios
17.
J Fish Biol ; 104(2): 410-421, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36740452

RESUMO

The tapertail anchovy Coilia brachygnathus, a commercially important species mainly distributed along the mid-lower Chang-Jiang basin, is by far the most dominant species in Lake Honghu. To figure out its success in this semiclosed lake, some basic biological parameters of this anchovy were analysed based on samples seasonally collected from October 2020 to December 2021. The results demonstrated that the age classes of fished individuals varied from 0.5 to 3.5, with the majority (97.36%) being between 0.5 and 3 years old. The size at 50% maturity of 17.2 cm total length (TL) for females and 19.0 cm TL for males corresponded to 1 and 1.6 years, respectively. Coilia brachygnathus has a short life span, early sexual maturity and a relatively fast growth rate. The flourishing of the fish in the lake is mainly attributed to its short life span, early maturity, fast growth rate, closed fishing, pelagic spawners, the availability of plenty of food and low predation effect on it. Age 3.5 year occurs in an extremely small percentage of the total (<3%), indicating that a large number of larger-sized or older fish died after spawning, which is probably one of the major sources of water pollution if the closed fishing measure is adopted in Lake Honghu. Thus, individuals older than 2 years or more than 20.0 cm TL should be harvested. These findings have important management implications for the fish resources in Lake Honghu and beyond.


Assuntos
Peixes , Lagos , Masculino , Feminino , Animais , China
18.
J Fish Biol ; 104(2): 345-364, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37927158

RESUMO

China harbors a high species diversity of freshwater fishes not shared with any of its neighboring nations. Freshwater fish diversity in the country has been under severe threat from human activities over the past decades, thus conservation freshwater fishes and ecosystems is urgently needed. To accumulate baseline data for guiding protection actions, the third red list assessment of Chinese freshwater fishes was carried out. Among Chinese freshwater fishes assessed, there are 355 at-risk species (22.3% of the total), including 69 ranked as Critically Endangered, 97 as Endangered, and 189 as Vulnerable. Two species are classified as Extinct and one as Regionally Extinct. China's threat level seems to be lower than the known average level found in the IUCN's global assessment of freshwater fishes, but this is an artifact of a high rate of species classified as Data Deficient. Conservation of freshwater fishes is presently facing a grim situation in China. Imperilment of Chinese freshwater fishes is primarily attributed to habitat loss and degradation arising from human perturbations, particularly river damming. Despite the adoption of protected areas setting up, captive breeding and release, and a fishing moratorium, conservation efforts for freshwater fishes are compromised by disproportional attention in China's biodiversity conservation, baseline data deficiency, insufficiently designed protection networks, and inefficient or inadequate implementation of conservation strategies. To achieve the objectives of Chinese freshwater fish conservation, it is proposed to conduct a national-scale survey of fish diversity and reassess their at-risk status, develop systematic conservation planning of freshwater fish diversity and ecosystems, prioritize strategies for protected areas development, perform genetic-based captive breeding for releasing in concert with other protection actions, and implement flexible fishing moratorium strategies in different water bodies.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Humanos , Animais , Água Doce , Biodiversidade , China , Peixes/genética
19.
J Fish Biol ; 105(1): 141-152, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38653715

RESUMO

Ocean acidification could modify the bioavailability and chemical properties of trace elements in seawater, which could affect their incorporation into the calcareous structures of marine organisms. Fish otoliths, biomineralized ear stones made by aragonite, are suspended within the endolymph fluid of teleosts, indicating that the elemental incorporation of otoliths might also be susceptible to ocean acidification. In this study, we evaluated the combined effects of CO2-induced ocean acidification (pH 8.10, 7.70, and 7.30, corresponding to ocean acidification scenarios under the representative concentration pathway 8.5 model as projected by the Intergovernmental Panel on Climate Change) and water elemental concentrations of strontium (Sr) and barium (Ba; low, medium, and high) on elemental incorporation into otoliths of the flounder Paralichthys olivaceus at early life stages. Our results revealed that the elemental incorporation of Sr and Ba into otoliths was principally dependent on the corresponding water elemental concentrations rather than on ocean acidification. Moreover, the partition coefficients (DMe) of Sr and Ba may stabilize after dynamic equilibrium is reached as the water elemental concentration increases, but are not affected by ocean acidification. Therefore, the incorporation of Sr and Ba into otoliths of the flounder at early life stages may not serve as an effective indicator of ocean acidification. In other words, the findings suggest that ocean acidification does not impact the incorporation of Sr and Ba incorporation into otoliths when tracing the temperature or salinity experiences of the flounder. Our findings will provide new knowledge for understanding the potential ecological effects of ocean acidification on the recruitment dynamics of fish species.


Assuntos
Bário , Linguado , Membrana dos Otólitos , Água do Mar , Estrôncio , Animais , Estrôncio/análise , Membrana dos Otólitos/química , Membrana dos Otólitos/crescimento & desenvolvimento , Bário/análise , Água do Mar/química , Linguado/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Dióxido de Carbono , Linguados/crescimento & desenvolvimento , Linguados/metabolismo , Mudança Climática , Acidificação dos Oceanos
20.
J Sci Food Agric ; 104(1): 196-206, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37555248

RESUMO

BACKGROUND: Schisandra chinensis (Turcz.) Baill, a fruit utilized in traditional Chinese medicine (TCM), has a long history of medical application. It has been used to treat diseases of the gastrointestinal tract. Schisandra chinensis (Turcz.) Baill polysaccharide (SACP) is an important biologically active ingredient that has been shown to have a variety of beneficial effects including immune regulation and anti-oxidative properties. Ulcerative colitis (UC) is a complicated gastrointestinal inflammatory disease. We explore the protective effect of SACP against UC. RESULTS: Schisandra chinensis (Turcz.) Baill polysaccharide significantly reduced the disease activity index (DAI) and levels of myeloperoxidase(MPO) and malondialdehyde (MDA) in colonic tissue. It also alleviated weight loss and histopathological damage of mice. The expression of MUC2 and occludin proteins was increased and the barrier function of the colonic mucosa was enhanced by SACP treatment. NF-κB pathway activation was also inhibited and the production of pro-inflammatory cytokines was decreased whereas anti-inflammatory cytokines were increased. 16SrDNA sequencing of fecal flora showed that SACP increased the abundance of Muribaculaceaeunclassified, LachnospiraceaeNK4A136group and reduced the abundance of Bacteroides and Erysipelatoclostridium. CONCLUSION: Schisandra chinensis (Turcz.) Baill polysaccharide can protect against Dextran Sulfate Sodium Salt (DSS)-induced ulcerative colitis in mice. © 2023 Society of Chemical Industry.


Assuntos
Colite Ulcerativa , Colite , Microbioma Gastrointestinal , Schisandra , Camundongos , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , NF-kappa B/genética , NF-kappa B/metabolismo , Schisandra/química , Schisandra/metabolismo , Polissacarídeos , Colo/metabolismo , Citocinas/metabolismo , Cloreto de Sódio , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças
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