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1.
Plant Biotechnol J ; 22(9): 2461-2471, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38735054

RESUMO

The reduction in crop yield caused by pathogens and pests presents a significant challenge to global food security. Genetic engineering, which aims to bolster plant defence mechanisms, emerges as a cost-effective solution for disease control. However, this approach often incurs a growth penalty, known as the growth-defence trade-off. The precise molecular mechanisms governing this phenomenon are still not completely understood, but they generally fall under two main hypotheses: a "passive" redistribution of metabolic resources, or an "active" regulatory choice to optimize plant fitness. Despite the knowledge gaps, considerable practical endeavours are in the process of disentangling growth from defence. The plant microbiome, encompassing both above- and below-ground components, plays a pivotal role in fostering plant growth and resilience to stresses. There is increasing evidence which indicates that plants maintain intimate associations with diverse, specifically selected microbial communities. Meta-analyses have unveiled well-coordinated, two-way communications between plant shoots and roots, showcasing the capacity of plants to actively manage their microbiota for balancing growth with immunity, especially in response to pathogen incursions. This review centers on successes in making use of specific root-associated microbes to mitigate the growth-defence trade-off, emphasizing pivotal advancements in unravelling the mechanisms behind plant growth and defence. These findings illuminate promising avenues for future research and practical applications.


Assuntos
Microbiota , Desenvolvimento Vegetal , Imunidade Vegetal , Raízes de Plantas/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/imunologia , Plantas/microbiologia , Plantas/imunologia , Plantas/metabolismo , Produtos Agrícolas/microbiologia , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/imunologia , Produtos Agrícolas/genética
2.
J Transl Med ; 22(1): 742, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107788

RESUMO

BACKGROUND: LARC patients commonly receive adjuvant therapy, however, hidden micrometastases still limit the improvement of OS. This study aims to investigate the impact of VASN in rectal cancer with pulmonary metastasis and understand the underlying molecular mechanisms to guide adjuvant chemotherapy selection. METHODS: Sequencing data from rectal cancer patients with pulmonary metastasis from Sun Yat-sen University Cancer Center (SYSUCC) and publicly available data were meticulously analyzed. The functional role of VASN in pulmonary metastasis was validated in vivo and in vitro. Coimmunoprecipitation (co-IP), immunofluorescence, and rescue experiments were conducted to unravel potential molecular mechanisms of VASN. Moreover, VASN expression levels in tumor samples were examined and analyzed for their correlations with pulmonary metastasis status, tumor stage, adjuvant chemotherapy benefit, and survival outcome. RESULTS: Our study revealed a significant association between high VASN expression and pulmonary metastasis in LARC patients. Experiments in vitro and in vivo demonstrated that VASN could promote the cell proliferation, metastasis, and drug resistance of colorectal cancer. Mechanistically, VASN interacts with the NOTCH1 protein, leading to concurrent activation of the NOTCH and MAPK pathways. Clinically, pulmonary metastasis and advanced tumor stage were observed in 90% of VASN-positive patients and 53.5% of VASN-high patients, respectively, and VASN-high patients had a lower five-year survival rate than VASN-low patients (26.7% vs. 83.7%). Moreover, the Cox analysis and OS analysis indicated that VASN was an independent prognostic factor for OS (HR = 7.4, P value < 0.001) and a predictor of adjuvant therapy efficacy in rectal cancer. CONCLUSIONS: Our study highlights the role of VASN in decreasing drug sensitivity and activating the NOTCH and MAPK pathways, which leads to tumorigenesis and pulmonary metastasis. Both experimental and clinical data support that rectal cancer patients with VASN overexpression detected in biopsies have a higher risk of pulmonary metastasis and adjuvant chemotherapy resistance.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares , Neoplasias Retais , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Feminino , Masculino , Neoplasias Retais/patologia , Neoplasias Retais/metabolismo , Neoplasias Retais/genética , Neoplasias Retais/tratamento farmacológico , Quimioterapia Adjuvante , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Pessoa de Meia-Idade , Animais , Regulação Neoplásica da Expressão Gênica , Camundongos Nus , Proliferação de Células/efeitos dos fármacos , Receptor Notch1/metabolismo , Receptor Notch1/genética , Proteínas dos Microfilamentos/metabolismo , Proteínas dos Microfilamentos/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos
3.
J Surg Oncol ; 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39434619

RESUMO

BACKGROUND AND OBJECTIVES: Endoscopic ultrasound (EUS) is an imaging modality that can be applied to predict preoperative T staging. It is important for the patient to decide whether to receive endoscopic therapy, surgical intervention, or neoadjuvant therapy. The objectives of our study were to (1) identify if EUS could precisely predict T1-stage tumor, which is suitable for endoscopic treatment and (2) identify if EUS could precisely predict tumors more advanced than T3, which would mandate neoadjuvant therapy. METHODS: A retrospective study of patients who received gastrectomy was conducted from March 2017 to December 2021 at Taichung Veterans General Hospital. Those who received preoperative EUS, with final pathology showing gastric adenocarcinoma were included. Consistency of EUS prediction and pathology, accuracy, and parameters impacting accuracy were analyzed. RESULTS: The κ value was 0.6 if the T stage was not grouped, indicating moderate agreement. Overall accuracy was 52.8%. Overestimation and underestimation rates were 17.6% and 29.5%, respectively. The accuracy of T stages is highest in T1 (85.23%). The κ value of T1-stage was 0.67, and those of T2, T3, and T4 were below 0.5. Regarding parameters affecting accuracy, we found longitudinal portion, Borrmann type, ulcer presentation, early gastric cancer, and size of tumor could influence the accuracy. CONCLUSIONS: Our study showed that EUS was a good tool for precisely predicting T1-stage of gastric adenocarcinoma preoperatively. For this situation, endoscopic treatment would be enough. However, for predicting more advanced gastric adenocarcinoma, EUS should be combined with other modalities to achieve better accuracy.

4.
J Formos Med Assoc ; 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38880710

RESUMO

BACKGROUND PURPOSE: Capsule endoscopy (CE) is a noninvasive examination for excellent visualization of small bowel mucosal lesions. We aimed to evaluate the clinical efficacy and safety of CE in pediatric patients. METHODS: From April 2014 to December 2022, CE procedures performed in children younger than 18 years of age at Taichung Veteran General Hospital were analyzed retrospectively. RESULTS: Among 136 procedures, the completion rate was 95.6% (n = 130), with a median age of 14 years old. Suspicion or evaluation of inflammatory bowel diseases (IBD) (41%) was the most common indication for CE. Other common indications of CE were chronic unexplained abdominal pain (35%) and obscure gastrointestinal bleeding or iron deficiency anemia (21%). No procedure-related complications occurred. The diagnosis of those patients with incomplete study were CD with small bowel stricture, graft-versus-host disease and duodenal ulcers. A total of 86 CE procedures showed positive findings, and the overall diagnostic yield rate was 63.2%. Small bowel ulcers (65.12%) were the most common findings. Overall, 26.5% of CE examinations resulted in a new diagnosis and 44.9% of CE exams led to a change in therapy. For patients with IBD, CE findings resulted in an even higher therapeutic change rate of 48.1%. CONCLUSIONS: CE is a safe and feasible diagnostic method to study the small intestine in children, especially for IBD. Incomplete study could be an indicator of positive finding and can potentially be a guide to identify the site of possible strictures.

5.
J Hum Nutr Diet ; 36(5): 1649-1660, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37485801

RESUMO

BACKGROUND: Crohn's disease (CD) is a progressive inflammatory disease of the gastrointestinal tract associated with malnutrition, high levels of inflammation and calcium and magnesium deficiencies. However, the relationships between these symptoms are poorly defined. METHOD: Seventy-six adult CD patients who had not yet started treatment and 83 healthy volunteers were recruited. The dietary intakes, serum calcium and magnesium levels, nutritional indicators and biochemical markers of disease activity were measured. RESULTS: Most participants had inadequate magnesium and calcium intake. The serum magnesium and calcium levels, as well as nutritional and inflammatory indicators, differed significantly between CD patients and controls, especially in the active phase. Serum levels of magnesium and calcium correlated with both nutritional status and inflammation. The cut-off values for CD development were 0.835 mmol/L (magnesium) and 2.315 mmol/L (calcium), whereas those for the active phase were 0.785 and 2.28 mmol/L, respectively. CONCLUSION: Adequate intake of magnesium and calcium may both improve the nutritional status of CD patients and reduce inflammation, benefiting disease relief. As both magnesium and calcium reflect CD status, they may be useful markers for CD diagnosis and disease activity.


Assuntos
Doença de Crohn , Adulto , Humanos , Doença de Crohn/diagnóstico , Cálcio , Magnésio , Estado Nutricional , Cálcio da Dieta , Inflamação
6.
Small ; 18(4): e2107265, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34908242

RESUMO

Designing heterogeneous interfaces and components at the nanoscale is proven effective for optimizing electromagnetic wave absorption and shielding properties, which can achieve desirable dielectric polarization and ferromagnetic resonances. However, it remains a challenge for the precise control of components and microstructures via an efficient synthesis approach. Here, the arc-discharged plasma method is proposed to synthesize core@shell structural high-entropy-alloy@graphite nanocapsules (HEA@C-NPs), in which the HEA nanoparticles are in situ encapsulated within a few layers of graphite through the decomposition of methane. In particular, the HEA cores can be designed via combinations of various transition elements, presenting the optimized interfacial impedance matching. As an example, the FeCoNiTiMn HEA@C-NPs obtain the minimum reflection loss (RLmin ) of -33.4 dB at 7.0 GHz (3.34 mm) and the efficient absorption bandwidth (≤-10 dB) of 5.45 GHz ranging from 12.55 to 18.00 GHz with an absorber thickness of 1.9 mm. The present approach can be extended to other carbon-coated complex components systems for various applications.

7.
Angew Chem Int Ed Engl ; 60(52): 27113-27118, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34605601

RESUMO

Photothermal materials with broadband optical absorption and high conversion efficiency are intensively pursued to date. Here, proposing by the d-d interband transitions, we report an unprecedented high-entropy alloy FeCoNiTiVCrCu nanoparticles that the energy regions below and above the Fermi level (±4 eV) have been fully filled by the 3d transition metals, which realizes an average absorbance greater than 96 % in the entire solar spectrum (wavelength of 250 to 2500 nm). Furthermore, we also calculated the photothermal conversion efficiency and the evaporation rate towards the steam generation. Due to its pronounced full light capture and ultrafast local heating, our high-entropy-alloy nanoparticle-based solar steam generator has over 98 % efficiency under one sun irradiation, meanwhile enabling a high evaporation rate of 2.26 kg m-2 h-1 .

8.
J Am Chem Soc ; 142(50): 21110-21121, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33263388

RESUMO

High-stability, zirconium-based metal-organic frameworks are attractive as heterogeneous catalysts and as model supports for uniform arrays of subsequently constructed heterogeneous catalysts-for example, MOF-node-grafted metal-oxy and metal-sulfur clusters. For hexa-Zr(IV)-MOFs characterized by nodes that are less than 12-connected, sites not used for linkers are ideally occupied by reactive and displaceable OH/H2O pairs. The desired pairs are ideal for grafting the aforementioned catalytic clusters, while aqua-ligand lability renders them effective for exposing highly Lewis-acidic Zr(IV) sites (catalytic sites) to candidate reactants. New single-crystal X-ray studies of an eight-connected Zr-MOF, NU-1000, reveal that conventional activation fully removes modulator ligands, but replaces them with three node-blocking formate ligands (from solvent decomposition) and only one OH/H2O pair, not four-a largely overlooked complication that now appears to be general for Zr-MOFs. Here we describe an alternative activation protocol that effectively removes modulators, avoids formate, and installs the full complement of terminal OH/H2O pairs. It does so via an unusual isolatable intermediate featuring eight aqua ligands and four non-ligated chlorides-again as supported by single-crystal X-ray data. We find that complete replacement of node-blocking modulators/formate with the originally envisioned OH/OH2 pairs has striking consequences; here we touch upon just three. First, elimination of unrecognized formate renders aqua ligands much more thermally labile, enabling open Zr(IV) sites to be obtained at lower temperature. Second, in the absence of formate, which otherwise links and locks pairs of node Zr(IV) ions, reversible removal of aqua ligands engenders reversible contraction of MOF meso- and micropores, as evidenced by X-ray diffraction. Third, formate replacement with OH/OH2 pairs renders NU-1000 ca.10× more active for catalytic hydrolytic degradation of a representative simulant of G-type chemical warfare agents.

9.
J Am Chem Soc ; 140(36): 11174-11178, 2018 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-30141922

RESUMO

To modify its steric and electronic properties as a support for heterogeneous catalysts, electron-withdrawing and electron-donating ligands, hexafluoroacetylacetonate (Facac-) and acetylacetonate (Acac-), were introduced to the metal-organic framework (MOF), NU-1000, via a process akin to atomic layer deposition (ALD). In the absence of Facac- or Acac-, NU-1000-supported, AIM-installed Ni(II) sites yield a mixture of C4, C6, C8, and polymeric products in ethylene oligomerization. (AIM = ALD-like deposition in MOFs). In contrast, both Ni-Facac-AIM-NU-1000 and Ni-Acac-AIM-NU-1000 exhibit quantitative catalytic selectivity for C4 species. Experimental findings are supported by density functional theory calculations, which show increases in the activation barrier for the C-C coupling step, due mainly to rearrangement of the siting of Facac- or Acac- to partially ligate added nickel. The results illustrate the important role of structure-tuning support modifiers in controlling the activity of MOF-sited heterogeneous catalysts and in engendering catalytic selectivity. The results also illustrate the ease with which crystallographically well-defined modifications of the catalyst support can be introduced when the node-coordinating molecular modifier is delivered via the vapor phase.

12.
Hum Mol Genet ; 21(9): 2124-31, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22323359

RESUMO

A variety of conditions lead to anemia, which affects one-quarter of the world's population. Previous genome-wide association studies revealed a number of genetic polymorphisms significantly associated with plasma iron status. To evaluate the association of genetic variants in genes involved in iron delivery and hepcidin regulation pathways with the risk of iron-deficiency anemia (IDA), the following single nucleotide polymorphisms were genotyped in 2139 unrelated elderly Chinese women: rs3811647 (TF), rs7385804 (TFR2), rs235756 (BMP2), and rs855791(V736A) and rs4820268 (TMPRSS6, encoding matriptase-2). We identified common variants in TMPRSS6 as being genetic risk factors for both iron deficiency (OR(rs855791) = 1.55, P = 4.96 × 10(-8)) and IDA (OR(rs855791) = 1.78, P = 8.43 × 10(-9)). TMPRSS6 polymorphisms were also associated with lower serum iron (SI) and hemoglobin levels, consistent with their associations to increased iron deficiency and anemia risk. Variants rs3811647 in TF and rs7385804 in TFR2 were associated with reduced SI, serum transferrin and transferrin saturation levels; however, these variants were not associated with iron deficiency or anemia risk. Our findings suggest that TF, TFR2 and TMPRSS6 polymorphisms are significantly associated with decreased iron status, but only variants in TMPRSS6 are genetic risk factors for iron deficiency and IDA.


Assuntos
Anemia Ferropriva/genética , Proteína Morfogenética Óssea 2/genética , Proteínas de Membrana/genética , Receptores da Transferrina/genética , Serina Endopeptidases/genética , Transferrina/genética , Idoso , Anemia Ferropriva/sangue , Povo Asiático/genética , Estudos de Casos e Controles , China , Estudos de Coortes , Feminino , Predisposição Genética para Doença , Hemoglobinas/metabolismo , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores de Risco
13.
Angew Chem Int Ed Engl ; 53(39): 10471-5, 2014 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-25088553

RESUMO

Highly enantioselective [3+2] coupling of 3-substituted indoles with quinone monoimines promoted by a chiral phosphoric acid has been reported. A large variety of benzofuroindolines were prepared in moderate to good yields (up to 98%) with generally excellent enantioselectivities (up to 99% ee).


Assuntos
Iminas/química , Indóis/química , Ácidos Fosfóricos/química , Quinonas/química , Catálise , Cristalografia por Raios X , Reação de Cicloadição , Iminas/síntese química , Conformação Molecular , Estereoisomerismo
14.
Plant Sci ; 347: 112200, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39038707

RESUMO

Receptor-like kinases (RLKs) constitute a diverse superfamily of proteins pivotal for various plant physiological processes, including responses to pathogens, hormone perception, growth, and development. Their ability to recognize conserved epitopes for general elicitors and specific pathogens marked significant advancements in plant pathology research. Emerging evidence suggests that RLKs and associated components also act as modulators in hormone signaling and cellular trafficking, showcasing their multifunctional roles in growth and development. Notably, STRESS INDUCED FACTOR 2 (SIF2) stands out as a representative with distinct expression patterns in different Arabidopsis organs. Our prior work highlighted the specific induction of SIF2 expression in guard cells, emphasizing its positive contribution to stomatal immunity. Expanding on these findings, our present study delves into the diverse functions of SIF2 expression in root tissues. Utilizing comprehensive physiology, molecular biology, protein biochemistry, and genetic analyses, we reveal that SIF2 modulates abscisic acid (ABA) signaling in Arabidopsis roots. SIF2 is epistatic with key regulators in the ABA signaling pathway, thereby governing the expression of genes crucial for dormancy release and, consequently, Arabidopsis seed germination. This study sheds light on the intricate roles of SIF2 as a multi-functional RLK, underscoring its organ-specific contributions to plant immunity, hormonal regulation, and seed germination.


Assuntos
Ácido Abscísico , Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Germinação , Arabidopsis/genética , Arabidopsis/fisiologia , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Germinação/genética , Ácido Abscísico/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/genética , Sementes/fisiologia , Sementes/metabolismo , Transdução de Sinais , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Raízes de Plantas/fisiologia , Imunidade Vegetal/genética
15.
J Clin Med ; 13(13)2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38999217

RESUMO

Background/Objectives: Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated disorder presenting as mass-like lesions with obstructions. An elevated serum IgG4 level is identified in more than half of affected patients and is considered a diagnostic criterion. IgG4-RD is still easily misdiagnosed as neoplastic or infectious disease. We aimed to conduct a hospital-based study to illuminate the association between serum IgG4 levels and pancreatobiliary disorders and cancer. Methods: In this study, serum IgG4 levels were assessed at our hospital's immunology laboratory, utilizing data from the hospital's computer center, and the diagnostic codes used were based on ICD-9-CM. We analyzed IgG4 level data collected between April 2013 and April 2020, including patients' age, gender, and diseases, but excluding the rationale for IgG4 level assessment. Employing propensity score matching (PSM) at a 1:1 ratio to mitigate age and gender confounding, we analyzed 759 patients divided into groups by IgG4 levels (≤140 and >140 mg/dL; and ≤140, 141-280, >280 mg/dL). We explored associations between IgG4 levels and conditions such as pancreatobiliary cancer (the group included cholangiocarcinoma, pancreatic cancer, and ampullary cancer), cholangitis, cholangiocarcinoma, pancreatitis, pancreatic cancer, and ampullary cancer. Results: Our study analyzed the demographics, characteristics, and serum IgG4 levels of participants and found no significant differences in serum IgG4 levels across various pancreatobiliary conditions. Nevertheless, the crude odds ratios (ORs) suggested a nuanced association between a higher IgG4 level > 280 mg/dL and increased risks of cancer and pancreatitis, with crude ORs of 1.52 (p = 0.03) and 1.49 (p = 0.008), respectively. After PSM matching, the further analysis of 759 matched patients showed no significant differences in IgG4 levels > 140 mg/dL between cancerous and non-cancerous groups, nor across other pancreatobiliary conditions. A higher serum IgG4 level > 280 mg/dL was significantly associated with pancreatobiliary cancer and cholangiocarcinoma, with crude ORs of 1.61 (p = 0.026) and 1.62 (p = 0.044), respectively. In addition, IgG4 > 280 mg/dL showed a greater association with pancreatic cancer compared with 141-280 mg/dL, with crude OR of 2.18 (p = 0.038). Conclusions: Our study did not find a clear association between serum IgG4 levels (>140 mg/dL) and pancreatobiliary cancer. We observed that higher IgG4 levels (>280 mg/dL) may be associated with cholangiocarcinoma and pancreatic cancer, as indicated by crude ORs. However, the adjusted analysis did not demonstrate the significant association between IgG4 level > 280 mg/dL and cancer. Considering IgG4-RD as a chronic and persistent inflammatory status, it is more closely associated with inflammatory diseases than with cancer. Therefore, further long-term cohort studies are necessary to evaluate the potential role of IgG4 levels in cancer risk among these patients.

16.
ACS Appl Mater Interfaces ; 16(31): 41027-41035, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39048298

RESUMO

High-entropy-alloy nanoparticles (HEA-NPs) composed of 3d transition metallic elements have attracted intensive attention in photothermal conversion regions due to their d-d interband transitions (IBTs). However, the effect arising from the unbalanced elemental ratio still needs more focus. In this work, FeCoNiCrMn HEA-NPs with different elemental ratios among Cr and Mn have been employed to clarify the impact of different composed elements on the optical absorption and photothermal conversion performance. It can be recognized that the unbalanced elemental ratio of HEA-NPs can reduce the photothermal performance. Density functional theory calculation demonstrated that d-d IBTs can be changed by the different composed element ratios, resulting in a number of insufficient filling regions around the Fermi level (±4 eV). As a result, the HEA-NPs (FeCoNiCr0.75Mn0.25) with a balanced elemental ratio exhibit the highest surface temperature of 97.6 °C under 1 sun irradiation, and the evaporation rate and energy conversion efficiency could reach 2.13 kg·m-2·h-1 and 93%, respectively, demonstrating effective solar steam generation behavior.

17.
Aging Dis ; 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39012671

RESUMO

Fatigue, commonly experienced in daily life, is a feeling of extreme tiredness, shortage or lack of energy, exhaustion, and difficulty in performing voluntary tasks. Central fatigue, defined as a progressive failure to voluntarily activate the muscle, is typically linked to moderate- or light-intensity exercise. However, in some instances, high-intensity exercise can also trigger the onset of central fatigue. Exercise-induced central fatigue often precedes the decline in physical performance in well-trained athletes. This leads to a reduction in nerve impulses, decreased neuronal excitability, and an imbalance in brain homeostasis, all of which can adversely impact an athlete's performance and the longevity of their sports career. Therefore, implementing strategies to delay the onset of exercise-induced central fatigue is vital for enhancing athletic performance and safeguarding athletes from the debilitating effects of fatigue. In this review, we discuss the structural basis, measurement methods, and biomarkers of exercise-induced central fatigue. Furthermore, we propose non-pharmacological interventions to mitigate its effects, which can potentially foster improvements in athletes' performances in a healthful and sustainable manner.

18.
bioRxiv ; 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39345551

RESUMO

As a fundamental biological process, DNA replication ensures the accurate copying of genetic information. However, the impact of this process on cellular plasticity in multicellular organisms remains elusive. Here, we find that reducing the level or activity of a replication component, DNA Polymerase α (Polα), facilitates cell reprogramming in diverse stem cell systems across species. In Drosophila male and female germline stem cell lineages, reducing Polα levels using heterozygotes significantly enhances fertility of both sexes, promoting reproductivity during aging without compromising their longevity. Consistently, in C. elegans the pola heterozygous hermaphrodites exhibit increased fertility without a reduction in lifespan, suggesting that this phenomenon is conserved. Moreover, in male germline and female intestinal stem cell lineages of Drosophila, polα heterozygotes exhibit increased resistance to tissue damage caused by genetic ablation or pathogen infection, leading to enhanced regeneration and improved survival during post-injury recovery, respectively. Additionally, fine tuning of an inhibitor to modulate Polα activity significantly enhances the efficiency of reprogramming human embryonic fibroblasts into induced pluripotent cells. Together, these findings unveil novel roles of a DNA replication component in regulating cellular reprogramming potential, and thus hold promise for promoting tissue health, facilitating post-injury rehabilitation, and enhancing healthspan.

19.
Front Bioeng Biotechnol ; 11: 1271140, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37711454

RESUMO

Desired orthopedic implant materials must have a good biological activity and possess appropriate mechanical property that correspond to those of human bone. Although polyetheretherketone (PEEK) has displayed a promising application prospect in musculoskeletal and dentistry reconstruction thanks to its non-biodegradability and good biocompatibility in the body, the poor osseointegration and insufficient mechanical strength have significantly limited its application in the repair of load-bearing bones and surgical operations. In this study, carbon nanotubes (CNT)/calcium silicate (CS)/polyetheretherketone ternary composites were fabricated for the first time. The addition of CS was mainly aimed at improving biological activities and surface hydrophilicity, but it inevitably compromised the mechanical strength of PEEK. CNT can reinforce the composites even when brittle CS was introduced and further upgraded the biocompatibility of PEEK. The CNT/CS/PEEK composites exhibited higher mechanical strengths in tensile and bending tests, 64% and 90% higher than those of brittle CS/PEEK binary composites. Besides, after incorporation of CNT and CS into PEEK, the hydrophilicity, surface roughness and ability to induce apatite-layer deposition were significantly enhanced. More importantly, the adhesion, proliferation, and osteogenic differentiation of mouse embryo osteoblasts were effectively promoted on CNT/CS/PEEK composites. In contrast to PEEK, these composites exhibited a more satisfactory biocompatibility and osteoinductive activity. Overall, these results demonstrate that ternary CNT/CS/PEEK composites have the potential to serve as a feasible substitute to conventional metal alloys in musculoskeletal regeneration and orthopedic implantation.

20.
Cell Rep ; 42(7): 112723, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37384531

RESUMO

RNA granules are membraneless condensates that provide functional compartmentalization within cells. The mechanisms by which RNA granules form are under intense investigation. Here, we characterize the role of mRNAs and proteins in the formation of germ granules in Drosophila. Super-resolution microscopy reveals that the number, size, and distribution of germ granules is precisely controlled. Surprisingly, germ granule mRNAs are not required for the nucleation or the persistence of germ granules but instead control their size and composition. Using an RNAi screen, we determine that RNA regulators, helicases, and mitochondrial proteins regulate germ granule number and size, while the proteins of the endoplasmic reticulum, nuclear pore complex, and cytoskeleton control their distribution. Therefore, the protein-driven formation of Drosophila germ granules is mechanistically distinct from the RNA-dependent condensation observed for other RNA granules such as stress granules and P-bodies.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Grânulos Citoplasmáticos/metabolismo , Drosophila/genética , Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Grânulos de Ribonucleoproteínas de Células Germinativas , Células Germinativas/metabolismo , RNA/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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