Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 473
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Plant Physiol ; 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38753299

RESUMEN

The transcriptional regulation of aluminum (Al) tolerance in plants is largely unknown, although Al toxicity restricts agricultural yields in acidic soils.. Here, we identified a NAM, ATAF1/2, and cup-shaped cotyledon 2 (NAC) transcription factor that participates in Al tolerance in Arabidopsis (Arabidopsis thaliana). Al substantially induced the transcript and protein levels of ANAC070, and loss-of-function anan070 mutants showed remarkably increased Al sensitivity, implying a beneficial role of ANAC070 in plant tolerance to Al toxicity. Further investigation revealed that more Al accumulated in the roots of anac070 mutants, especially in root cell walls, accompanied by a higher hemicellulose and xyloglucan level, implying a possible interaction between ANAC070 and genes that encode proteins responsible for the modification of xyloglucan, including xyloglucan endo-transglycosylases/hydrolase (XTH) or ANAC017. Yeast one hybrid analysis revealed a potential interaction between ANAC070 and ANAC017, but not for other XTHs. Furthermore, dual-luciferase reporter assay, RT-qPCR, and GUS analysis revealed that ANAC070 could directly repress the transcript levels of ANAC017, and knockout of ANAC017 in the anac070 mutant partially restored its Al sensitivity phenotype, indicating that ANAC070 contributes to Al tolerance mechanisms other than suppression of ANAC017 expression. Further analysis revealed that the core transcription factor SENSITIVE TO PROTON RHIZOTOXICITY1 (STOP1) and its target genes, which control Al tolerance in Arabidopsis, may also be involved in ANAC070-regulated Al tolerance. In summary, we identified a transcription factor, ANAC070, that represses the ANAC017-XTH31 module to regulate Al tolerance in Arabidopsis.

2.
Plant J ; 114(1): 176-192, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36721978

RESUMEN

The supply of boron (B) alleviates the toxic effects of aluminum (Al) on root growth; however, the mechanistic basis of this process remains elusive. This study filled this knowledge gap, demonstrating that boron modifies auxin distribution and transport in Al-exposed Arabidopsis roots. In B-deprived roots, treatment with Al induced an increase in auxin content in the root apical meristem zone (MZ) and transition zone (TZ), whereas in the elongation zone (EZ) the auxin content was decreased beyond the level required for adequate growth. These distribution patterns are explained by the fact that basipetal auxin transport from the TZ to the EZ was disrupted by Al-inhibited PIN-FORMED 2 (PIN2) endocytosis. Experiments involving the modulation of protein biosynthesis by cycloheximide (CHX) and transcriptional regulation by cordycepin (COR) demonstrated that the Al-induced increase of PIN2 membrane proteins was dependent upon the inhibition of PIN2 endocytosis, rather than on the transcriptional regulation of the PIN2 gene. Experiments reporting on the profiling of Al3+ and PIN2 proteins revealed that the inhibition of endocytosis of PIN2 proteins was the result of Al-induced limitation of the fluidity of the plasma membrane. The supply of B mediated the turnover of PIN2 endosomes conjugated with indole-3-acetic acid (IAA), and thus restored the Al-induced inhibition of IAA transport through the TZ to the EZ. Overall, the reported results demonstrate that boron supply mediates PIN2 endosome-based auxin transport to alleviate Al toxicity in plant roots.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Aluminio/toxicidad , Aluminio/metabolismo , Boro/metabolismo , Proteína 1 de Unión a Repeticiones Teloméricas/metabolismo , Raíces de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Arabidopsis/metabolismo
3.
Planta ; 259(3): 52, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38289400

RESUMEN

MAIN CONCLUSION: Auxin acts upstream of NO through NOA and XXT5 pathways to regulate the binding capacity of the root cell wall to Al. In our previous study, we identified an unknown mechanism by which 1-naphthaleneacetic acid (NAA) decreased the fixation of aluminum (Al) in the cell wall. Here, we observed that external application of the nitric oxide (NO) donor S-nitrosoglutathion (GSNO) increased the inhibition of Al on root elongation. Further analysis indicated that GSNO could induce Al accumulation in the roots and root cell walls, which is consistent with lower xyloglucan content. In comparison to the Columbia-0 (Col-0) wild type (WT), endogenous NO-reduced mutants noa1 (NOA pathway) and nia1nia2 (NR pathway) were more resistant to Al, with lower root Al content, higher xyloglucan content, and more Al accumulation in the root cell walls. By contrast, the xxt5 mutant with reduced xyloglucan content exhibited an Al-sensitive phenotype. Interestingly, Al treatment increased the endogenous auxin and NO levels, and the auxin levels induced under Al stress further stimulated NO production. Auxin application reduced Al retention in hemicellulose and decreased the xyloglucan content, similar to the effects observed with GSNO. In yucca and aux1-7 mutants, exogenous application of NO resulted in responses similar to those of the WT, whereas exogenous auxin had little effect on the noa1 mutant under Al stress. In addition, as auxin had similar effects on the nia1nia2 mutant and the WT, exogenous auxin and NO had little effect on the xxt5 mutant under Al stress, further confirming that auxin acts upstream of NO through NOA and XXT5 pathways to regulate the binding capacity of the root cell wall to Al.


Asunto(s)
Arabidopsis , Glucanos , Óxido Nítrico , Xilanos , Arabidopsis/genética , Aluminio/farmacología , Pared Celular , Ácidos Indolacéticos
4.
J Med Virol ; 96(5): e29669, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38773784

RESUMEN

Chronic hepatitis B virus (HBV) infection remains a significant global health challenge due to its link to severe conditions like HBV-related cirrhosis and hepatocellular carcinoma (HCC). Although current treatments effectively reduce viral levels, they have limited impact on certain HBV elements, namely hepatitis B surface antigen (HBsAg) and covalently closed circular DNA (cccDNA). This highlights the urgent need for innovative pharmaceutical and biological interventions that can disrupt HBsAg production originating from cccDNA. In this study, we identified a natural furanocoumarin compound, Imperatorin, which markedly inhibited the expression of HBsAg from cccDNA, by screening a library of natural compounds derived from Chinese herbal medicines using ELISA assay and qRT-PCR. The pharmacodynamics study of Imperatorin was explored on HBV infected HepG2-NTCP/PHHs and HBV-infected humanized mouse model. Proteome analysis was performed on HBV infected HepG2-NTCP cells following Imperatorin treatment. Molecular docking and bio-layer interferometry (BLI) were used for finding the target of Imperatorin. Our findings demonstrated Imperatorin remarkably reduced the level of HBsAg, HBV RNAs, HBV DNA and transcriptional activity of cccDNA both in vitro and in vivo. Additionally, Imperatorin effectively restrained the actions of HBV promoters responsible for cccDNA transcription. Mechanistic study revealed that Imperatorin directly binds to ERK and subsequently interfering with the activation of CAMP response element-binding protein (CREB), a crucial transcriptional factor for HBV and has been demonstrated to bind to the PreS2/S and X promoter regions of HBV. Importantly, the absence of ERK could nullify the antiviral impact triggered by Imperatorin. Collectively, the natural compound Imperatorin may be an effective candidate agent for inhibiting HBsAg production and cccDNA transcription by impeding the activities of HBV promoters through ERK-CREB axis.


Asunto(s)
ADN Circular , Furocumarinas , Antígenos de Superficie de la Hepatitis B , Virus de la Hepatitis B , Transcripción Genética , Furocumarinas/farmacología , Humanos , Animales , Virus de la Hepatitis B/efectos de los fármacos , Virus de la Hepatitis B/genética , Antígenos de Superficie de la Hepatitis B/metabolismo , Antígenos de Superficie de la Hepatitis B/genética , Células Hep G2 , Ratones , ADN Circular/genética , ADN Circular/metabolismo , Transcripción Genética/efectos de los fármacos , Antivirales/farmacología , ADN Viral , Simulación del Acoplamiento Molecular , Replicación Viral/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/virología , Modelos Animales de Enfermedad , Regiones Promotoras Genéticas
5.
Plant Physiol ; 192(3): 1947-1968, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-36913259

RESUMEN

Dwarfism is an agronomic trait that has substantial effects on crop yield, lodging resistance, planting density, and a high harvest index. Ethylene plays an important role in plant growth and development, including the determination of plant height. However, the mechanism by which ethylene regulates plant height, especially in woody plants, remains unclear. In this study, a 1-aminocyclopropane-1-carboxylic acid synthase (ACC) gene (ACS), which is involved in ethylene biosynthesis, was isolated from lemon (Citrus limon L. Burm) and named CiACS4. Overexpression of CiACS4 resulted in a dwarf phenotype in Nicotiana tabacum and lemon and increased ethylene release and decreased gibberellin (GA) content in transgenic plants. Inhibition of CiACS4 expression in transgenic citrus significantly increased plant height compared with the controls. Yeast two-hybrid assays revealed that CiACS4 interacted with an ethylene response factor (ERF), CiERF3. Further experiments revealed that the CiACS4-CiERF3 complex can bind to the promoters of 2 citrus GA20-oxidase genes, CiGA20ox1 and CiGA20ox2, and suppress their expression. In addition, another ERF transcription factor, CiERF023, identified using yeast one-hybrid assays, promoted CiACS4 expression by binding to its promoter. Overexpression of CiERF023 in N. tabacum caused a dwarfing phenotype. CiACS4, CiERF3, and CiERF023 expression was inhibited and induced by GA3 and ACC treatments, respectively. These results suggest that the CiACS4-CiERF3 complex may be involved in the regulation of plant height by regulating CiGA20ox1 and CiGA20ox2 expression levels in citrus.


Asunto(s)
Citrus , Giberelinas , Giberelinas/farmacología , Giberelinas/metabolismo , Citrus/genética , Citrus/metabolismo , Etilenos/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
6.
Acta Pharmacol Sin ; 45(2): 312-326, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37833535

RESUMEN

Apoptosis plays a critical role in the development of heart failure, and sphingosylphosphorylcholine (SPC) is a bioactive sphingolipid naturally occurring in blood plasma. Some studies have shown that SPC inhibits hypoxia-induced apoptosis in myofibroblasts, the crucial non-muscle cells in the heart. Calmodulin (CaM) is a known SPC receptor. In this study we investigated the role of CaM in cardiomyocyte apoptosis in heart failure and the associated signaling pathways. Pressure overload was induced in mice by trans-aortic constriction (TAC) surgery. TAC mice were administered SPC (10 µM·kg-1·d-1) for 4 weeks post-surgery. We showed that SPC administration significantly improved survival rate and cardiac hypertrophy, and inhibited cardiac fibrosis in TAC mice. In neonatal mouse cardiomyocytes, treatment with SPC (10 µM) significantly inhibited Ang II-induced cardiomyocyte hypertrophy, fibroblast-to-myofibroblast transition and cell apoptosis accompanied by reduced Bax and phosphorylation levels of CaM, JNK and p38, as well as upregulated Bcl-2, a cardiomyocyte-protective protein. Thapsigargin (TG) could enhance CaM functions by increasing Ca2+ levels in cytoplasm. TG (3 µM) annulled the protective effect of SPC against Ang II-induced cardiomyocyte apoptosis. Furthermore, we demonstrated that SPC-mediated inhibition of cardiomyocyte apoptosis involved the regulation of p38 and JNK phosphorylation, which was downstream of CaM. These results offer new evidence for SPC regulation of cardiomyocyte apoptosis, potentially providing a new therapeutic target for cardiac remodeling following stress overload.


Asunto(s)
Calmodulina , Insuficiencia Cardíaca , Fosforilcolina/análogos & derivados , Esfingosina/análogos & derivados , Ratones , Animales , Calmodulina/metabolismo , Calmodulina/farmacología , Calmodulina/uso terapéutico , Cardiomegalia/tratamiento farmacológico , Cardiomegalia/metabolismo , Insuficiencia Cardíaca/metabolismo , Miocitos Cardíacos , Transducción de Señal , Remodelación Ventricular , Ratones Endogámicos C57BL
7.
Molecules ; 29(3)2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38338318

RESUMEN

Theoretical and experimental investigations have shown that biochar, following KOH activation, enhances the efficiency of NO removal. Similarly, NaOH activation also improves NO removal efficiency, although the underlying mechanism remains unclear. In this study, zigzag configurations were employed as biochar models. Density functional theory (DFT) was utilized to examine how Li and Na single adsorption and OH co-adsorption affect the reaction pathways of NO reduction on the biochar surface. The rate constants for all reaction-determining steps (RDSs) within a temperature range of 200 to 1000 K were calculated using conventional transition state theory (TST). The results indicate a decrease in the activation energy for NO reduction reactions on biochar when activated by Li and Na adsorption, thus highlighting their beneficial role in NO reduction. Compared to the case with Na activation, Li-activated biochar exhibited superior performance in terms of the NO elimination rate. Furthermore, upon the adsorption of the OH functional group onto the Li-decorated and Na-decorated biochar models (LiOH-decorated and NaOH-decorated chars), the RDS energy barriers were higher than those of Li and Na single adsorption but easily overcome, suggesting effective NO reduction. In conclusion, Li-decorated biochar showed the highest reactivity due to its low RDS barrier and exothermic reaction on the surface.

8.
Lancet Oncol ; 24(6): 701-708, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37269846

RESUMEN

BACKGROUND: Small cell carcinoma of the cervix is a rare but poor prognosis pathological type of cervical cancer, for which advice in clinical guidelines is unspecific. We therefore aimed to investigate the factors and treatment methods that affect the prognosis of patients with small cell carcinoma of the cervix. METHODS: In this retrospective study, we collected data from the Surveillance, Epidemiology, and End Results (SEER) 18 registries cohort and a Chinese multi-institutional registry. The SEER cohort included females diagnosed with small cell carcinoma of the cervix between Jan 1, 2000, and Dec 31, 2018, whereas the Chinese cohort included women diagnosed between Jun 1, 2006, and April 30, 2022. In both cohorts, eligibility was limited to female patients older than 20 years with a confirmed diagnosis of small cell carcinoma of the cervix. Participants who were lost to follow-up or those for whom small cell carcinoma of the cervix was not the primary malignant tumour were excluded from the multi-institutional registry, and those with an unknown surgery status (in addition to those for whom small cell carcinoma of the cervix was not the primary malignant tumour) were excluded from the SEER data. The primary outcome of this study was overall survival (length of time from the date of first diagnosis until the date of death from any cause, or the last follow-up). Kaplan-Meier analysis, propensity score matching, and Cox-regression analyses were used to assess treatment outcomes and risk factors. FINDINGS: 1288 participants were included in the study; 610 in the SEER cohort and 678 in the Chinese cohort. Both univariable and multivariable Cox regression analysis (SEER hazard ratio [HR] 0·65 [95% CI 0·48-0·88], p=0·0058; China HR 0·53 [0·37-0·76], p=0·0005) showed that surgery was associated with a better prognosis. In subgroup analyses, surgery remained a protective factor for patients with locally advanced disease in both cohorts (SEER HR 0·61 [95% CI 0·39-0·94], p=0·024; China HR 0·59 [0·37-0·95]; p=0·029). Furthermore, the protective effect of surgery was observed among patients with locally advanced disease after propensity score matching in the SEER cohort (HR 0·52 [95% CI 0·32-0·84]; p=0·0077). In the China registry, surgery was associated with better outcomes in patients with stage IB3-IIA2 cancer (HR 0·17 [95% CI 0·05-0·50]; p=0·0015). INTERPRETATION: This study provides evidence that surgery improves outcomes of patients with small cell carcinoma of the cervix. Although guidelines recommend non-surgical methods as first-line treatment, patients with locally advanced disease or stage IB3-IIA2 cancer might benefit from surgery. FUNDING: The National Key R&D Program of China and the National Natural Science Foundation of China.


Asunto(s)
Carcinoma de Células Pequeñas , Neoplasias del Cuello Uterino , Femenino , Humanos , Carcinoma de Células Pequeñas/epidemiología , Carcinoma de Células Pequeñas/terapia , Carcinoma de Células Pequeñas/patología , Pueblos del Este de Asia , Estadificación de Neoplasias , Pronóstico , Sistema de Registros , Estudios Retrospectivos , Programa de VERF , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/terapia
9.
Carcinogenesis ; 44(1): 80-92, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-36300656

RESUMEN

Ovarian cancer is one of the deadliest malignant tumors. Ferroptosis is closely related to various cancers, including ovarian cancer, but the genes involved in regulating ferroptosis in ovarian cancer are still unclear. The aim of this study is to construct a long non-coding RNA (lncRNA) signature related to ferroptosis and evaluate its relationship with the prognosis and clinicopathological characteristics of patients with ovarian cancer. In this study, a prognostic risk model comprising 18 lncRNAs related to ferroptosis was obtained. Compared to the low-risk group, the high-risk group based on the FerRLSig score had significantly poorer overall survival (P < 0.001). The receiver operating characteristics curve supported the accuracy of the model, established a prognostic nomogram combining FerRLSig and clinical characteristics, and showed a good prognosis and survival risk stratification predictive power. In addition, Gene Set Enrichment Analysis (GSEA) showed that FerRLSig was involved in many malignant tumor-related immunomodulatory pathways. Based on the risk model, we found that immune status and immunotherapy, chemotherapy, and targeted therapy were significantly different between the high-risk and low-risk groups. This study provided a more in-depth understanding of the molecular and signaling pathways of ferroptosis in ovarian cancer and showed the impact of tumor microenvironment on ovarian cancer, as well as provided a prognostic model for ovarian cancer patients to guide the clinical treatment of ovarian cancer.


Asunto(s)
Ferroptosis , Neoplasias Ováricas , ARN Largo no Codificante , Humanos , Femenino , ARN Largo no Codificante/genética , Ferroptosis/genética , Neoplasias Ováricas/genética , Pronóstico , Nomogramas , Microambiente Tumoral
10.
Plant J ; 111(2): 529-545, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35596722

RESUMEN

Modification of the O-acetylation level of xyloglucan (XyG) appears to affect aluminum (Al) sensitivity in Arabidopsis by modulating its binding capacity to Al. However, the transcriptional regulation of this process remains largely unknown. In our previous studies, we found that the expression of TRICHOME BIREFRINGENCE-LIKE27 (TBL27), which is responsible for the O-acetylation of XyG, was downregulated under Al stress. In the present study, we showed that the expression of an R2R3-type transcription factor-encoding gene, MYB103, was also inhibited by Al exposure and exhibited a co-expression pattern with TBL27 in roots and siliques, suggesting a potential link between MYB103 and TBL27. The loss of function of MYB103 resulted in increased Al sensitivity, as indicated by more inhibited root growth and elevated root Al content compared with the wild type. Moreover, we also detected increased Al accumulation in the root cell wall and the hemicellulose fraction, which was attributed to the changes in the O-acetylation level of XyG rather than the XyG content itself. In addition, further analysis revealed that MYB103 positively activated TBL27 expression by directly binding to the TBL27 promoter region, and TBL27 overexpression in the myb103 mutant rescued the Al-sensitive phenotype of the mutant to the wild-type level. Taken together, we conclude that MYB103 acts upstream of TBL27 to positively regulate Al resistance by modulating the O-acetylation of the cell wall XyG.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Acetilación , Aluminio/metabolismo , Aluminio/toxicidad , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Birrefringencia , Pared Celular/metabolismo , Regulación de la Expresión Génica de las Plantas , Glucanos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Tricomas/genética , Tricomas/metabolismo , Xilanos
11.
Plant J ; 111(1): 164-182, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35460135

RESUMEN

Drought is a major environmental stress that severely affects plant growth and crop productivity. FRIGIDA (FRI) is a key regulator of flowering time and drought tolerance in model plants. However, little is known regarding its functions in woody plants, including citrus. Thus, we explored the functional role of the citrus FRI ortholog (CiFRI) under drought. Drought treatment induced CiFRI expression. CiFRI overexpression enhanced drought tolerance in transgenic Arabidopsis and citrus, while CiFRI suppression increased drought susceptibility in citrus. Moreover, transcriptomic profiling under drought conditions suggested that CiFRI overexpression altered the expression of numerous genes involved in the stress response, hormone biosynthesis, and signal transduction. Mechanistic studies revealed that citrus dehydrin likely protects CiFRI from stress-induced degradation, thereby enhancing plant drought tolerance. In addition, a citrus brassinazole-resistant (BZR) transcription factor family member (CiBZR1) directly binds to the CiFRI promoter to activate its expression under drought conditions. CiBZR1 also enhanced drought tolerance in transgenic Arabidopsis and citrus. These findings further our understanding of the molecular mechanisms underlying the CiFRI-mediated drought stress response in citrus.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Citrus , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Citrus/genética , Citrus/metabolismo , Sequías , Regulación de la Expresión Génica de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Estrés Fisiológico/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
12.
Planta ; 258(1): 7, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37222817

RESUMEN

MAIN CONCLUSION: The 4-coumarate:coenzyme A ligase 4CL4 is involved in enhancing rice P acquisition and use in acid soil by enlarging root growth and boosting functional rhizosphere microbe recruitment. Rice (Oryza sativa L.) cannot easily acquire phosphorus (P) from acid soil, where root growth is inhibited and soil P is fixed. The combination of roots and rhizosphere microbiota is critical for plant P acquisition and soil P mobilization, but the associated molecular mechanism in rice is unclear. 4CL4/RAL1 encodes a 4-coumarate:coenzyme A ligase related to lignin biosynthesis in rice, and its dysfunction results in a small rice root system. In this study, soil culture and hydroponic experiments were conducted to examine the role of RAL1 in regulating rice P acquisition, fertilizer P use, and rhizosphere microbes in acid soil. Disruption of RAL1 markedly decreased root growth. Mutant rice plants exhibited decreased shoot growth, shoot P accumulation, and fertilizer P use efficiency when grown in soil-but not under hydroponic conditions, where all P is soluble and available for plants. Mutant ral1 and wild-type rice rhizospheres had distinct bacterial and fungal community structures, and wild-type rice recruited some genotype-specific microbial taxa associated with P solubilization. Our results highlight the function of 4CL4/RAL1 in enhancing rice P acquisition and use in acid soil, namely by enlarging root growth and boosting functional rhizosphere microbe recruitment. These findings can inform breeding strategies to improve P use efficiency through host genetic manipulation of root growth and rhizosphere microbiota.


Asunto(s)
Coenzima A Ligasas , Oryza , Fósforo , Rizosfera , Coenzima A Ligasas/genética , Fertilizantes , Oryza/genética , Fitomejoramiento , Suelo
13.
J Med Virol ; 95(3): e28578, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36846971

RESUMEN

Hepatitis B surface antigen (HBsAg) loss and seroconversion, which is considered as functional cure of chronic Hepatitis B virus (HBV) infection, is rarely achieved even after long-term antiviral treatments. Therefore, new antiviral strategies interfering with other HBV replication steps are required, especially those that could efficiently inhibit HBsAg production. Here, we identified novel anti-HBV compounds that could potently block HBsAg expression from cccDNA by screening a natural compound library derived from Chinese traditional medical plants by a novel screening strategy. The combination of ELISA assay detecting the HBsAg and real-time PCR detecting HBV RNAs as indicator for cccDNA transcriptional activity were used. The antiviral activity of a candidate compound and underlying mechanism were evaluated in HBV-infected cells and a humanized liver mouse model. Herein, we selected a highly effective low-cytotoxic compound sphondin, which could effectively inhibit both intracellular HBsAg production and HBV RNAs levels. Moreover, we found that sphondin markedly inhibited cccDNA transcriptional activity without affecting cccDNA level. Mechanistic study found sphondin preferentially bound to HBx protein by residue Arg72, which led to increased 26S proteasome-mediated degradation of HBx. Sphondin treatment significantly reduced the recruitment of HBx to cccDNA, which subsequently led to inhibition of cccDNA transcription and HBsAg expression. The absence of HBx or R72A mutation potently abrogated the antiviral effect induced by sphondin in HBV-infected cells. Collectively, sphondin may be considered as a novel and natural antiviral agent directly targeting HBx protein, which effectively inhibited cccDNA transcription and HBsAg expression.


Asunto(s)
Antígenos de Superficie de la Hepatitis B , Hepatitis B Crónica , Animales , Ratones , Antígenos de Superficie de la Hepatitis B/genética , Hepatitis B Crónica/tratamiento farmacológico , Virus de la Hepatitis B/fisiología , Antivirales/uso terapéutico , ADN Viral/genética , ADN Circular , Replicación Viral
14.
Plant Physiol ; 189(4): 2517-2534, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35512200

RESUMEN

Aluminum (Al) toxicity is one of the key factors limiting crop production in acid soils; however, little is known about its transcriptional regulation in plants. In this study, we characterized the role of a NAM, ATAF1/2, and cup-shaped cotyledon 2 (NAC) transcription factors (TFs), ANAC017, in the regulation of Al tolerance in Arabidopsis (Arabidopsis thaliana). ANAC017 was localized in the nucleus and exhibited constitutive expression in the root, stem, leaf, flower, and silique, although its expression and protein accumulation were repressed by Al stress. Loss of function of ANAC017 enhanced Al tolerance when compared with wild-type Col-0 and was accompanied by lower root and root cell wall Al content. Furthermore, both hemicellulose and xyloglucan content decreased in the anac017 mutants, indicating the possible interaction between ANAC017 and xyloglucan endotransglucosylase/hydrolase (XTH). Interestingly, the expression of XTH31, which is responsible for xyloglucan modification, was downregulated in the anac017 mutants regardless of Al supply, supporting the possible interaction between ANAC017 and XTH31. Yeast one-hybrid, dual-luciferase reporter assay, and chromatin immunoprecipitation-quantitative PCR analysis revealed that ANAC017 positively regulated the expression of XTH31 through directly binding to the XTH31 promoter region, and overexpression of XTH31 in the anac017 mutant background rescued its Al-tolerance phenotype. In conclusion, we identified that the tTF ANAC017 acts upstream of XTH31 to regulate Al tolerance in Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Aluminio/metabolismo , Aluminio/toxicidad , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Pared Celular/genética , Pared Celular/metabolismo , Regulación de la Expresión Génica de las Plantas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
15.
Opt Lett ; 48(2): 247-250, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36638429

RESUMEN

The authors demonstrate the enhanced light output from 275-nm AlGaN-based deep ultraviolet (DUV) light-emitting diode (LED) structures via the in-plane modulation of shallow photonic crystal (PC) patterns that were fabricated on the p-AlGaN contact layer surface. The employed PC lattice constants are in the range of 270-780 nm, much larger than the fundamental Bragg order lattice constant (∼95 nm). As compared to the unpatterned sample, the intensity of the top (or bottom) emission can be enhanced by up to 331% (or 246%), attributed to the high-order coherent diffraction of the internal trapped light and also the Purcell enhancement of spontaneous emission. The findings in this Letter suggest an easier way for the realization of more energy-efficient DUV LEDs which offer the advantage of high emission for various applications in disinfection and sterilization.

16.
BMC Cancer ; 23(1): 173, 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36810001

RESUMEN

BACKGROUND: Novel antibody‒drug conjugates (ADC) have shown great efficacy in HER2-low advanced breast cancer. However, the clinical features of HER2-low disease still need to be clarified. The current study aims to evaluate the distribution and dynamic change in HER2 expression in patients with disease recurrence and the clinical outcome of those patients. METHODS: Patients with pathologically diagnosed relapsed breast cancer between 2009 and 2018 were included. Samples were considered HER2-zero when the immunohistochemistry (IHC) score was 0, HER2-low when the IHC score was 1 + or 2 + with negative fluorescence in situ hybridization (FISH) results, and HER2-positive when the IHC score was 3 + or the FISH results were positive. Breast cancer-specific survival (BCSS) was compared among the three HER2 groups. Changes in HER2 status were also evaluated. RESULTS: A total of 247 patients were included. Among recurrent tumors, 53 (21.5%) were HER2-zero, 127 (51.4%) were HER2-low, and 67 (27.1%) were HER2-positive. The HER2-low subtype represented 68.1% of the HR-positive breast cancer group and 31.3% of the HR-negative group (P < 0.001). This three-group classification of HER2 status was prognostic in advanced breast cancer (P = 0.0011), with HER2-positive patients having the best clinical outcome after disease recurrence (P = 0.024), while only marginal survival advantages were observed in HER2-low patients versus HER2-zero patients (P = 0.051). In the subgroup analysis, the survival difference was observed only in patients with HR-negative recurrent tumors (P = 0.0006) or with distant metastasis (P = 0.0037). The overall discordance rate of HER2 status between primary and recurrent tumors was 38.1%, with 25 (49.0%) primary HER2-zero patients and 19 (26.8%) HER2-positive patients shifting to HER2-low at recurrence. CONCLUSION: Nearly half of the advanced breast cancer patients had HER2-low disease, which indicates a poorer prognosis than HER2-positive disease and marginally better outcomes than HER2-zero disease. During disease progression, one-fifth of tumors convert to HER2-low entities, and the corresponding patients may benefit from ADC treatment.


Asunto(s)
Biomarcadores de Tumor , Receptor ErbB-2 , Humanos , Receptor ErbB-2/metabolismo , Biomarcadores de Tumor/metabolismo , Hibridación Fluorescente in Situ/métodos , Recurrencia Local de Neoplasia , Pronóstico
17.
Acta Pharmacol Sin ; 44(7): 1366-1379, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36721009

RESUMEN

Previous studies show that notoginsenoside R1 (NG-R1), a novel saponin isolated from Panax notoginseng, protects kidney, intestine, lung, brain and heart from ischemia-reperfusion injury. In this study we investigated the cardioprotective mechanisms of NG-R1 in myocardial ischemia/reperfusion (MI/R) injury in vivo and in vitro. MI/R injury was induced in mice by occluding the left anterior descending coronary artery for 30 min followed by 4 h reperfusion. The mice were treated with NG-R1 (25 mg/kg, i.p.) every 2 h for 3 times starting 30 min prior to ischemic surgery. We showed that NG-R1 administration significantly decreased the myocardial infarction area, alleviated myocardial cell damage and improved cardiac function in MI/R mice. In murine neonatal cardiomyocytes (CMs) subjected to hypoxia/reoxygenation (H/R) in vitro, pretreatment with NG-R1 (25 µM) significantly inhibited apoptosis. We revealed that NG-R1 suppressed the phosphorylation of transforming growth factor ß-activated protein kinase 1 (TAK1), JNK and p38 in vivo and in vitro. Pretreatment with JNK agonist anisomycin or p38 agonist P79350 partially abolished the protective effects of NG-R1 in vivo and in vitro. Knockdown of TAK1 greatly ameliorated H/R-induced apoptosis of CMs, and NG-R1 pretreatment did not provide further protection in TAK1-silenced CMs under H/R injury. Overexpression of TAK1 abolished the anti-apoptotic effect of NG-R1 and diminished the inhibition of NG-R1 on JNK/p38 signaling in MI/R mice as well as in H/R-treated CMs. Collectively, NG-R1 alleviates MI/R injury by suppressing the activity of TAK1, subsequently inhibiting JNK/p38 signaling and attenuating cardiomyocyte apoptosis.


Asunto(s)
Ginsenósidos , Daño por Reperfusión Miocárdica , Ratones , Animales , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Daño por Reperfusión Miocárdica/prevención & control , Daño por Reperfusión Miocárdica/metabolismo , Ginsenósidos/farmacología , Ginsenósidos/uso terapéutico , Ginsenósidos/metabolismo , Miocardio , Miocitos Cardíacos , Apoptosis
18.
Endocr Pract ; 29(9): 699-704, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37343764

RESUMEN

OBJECTIVE: To compare the incidence of cancer in patients with acromegaly with that of the local population in China and explore possible risk factors. METHODS: Data from 117 patients diagnosed with acromegaly at 2 centers between 2011 and 2022 were analyzed, and their cancer diagnoses were recorded. The cancer standardized incidence ratios (SIRs) and 95% confidence intervals (CIs) were calculated by comparison with those of the local population. The patients were divided into 2 groups, having cancer diagnosis or not. The relationships between cancer and sex, body mass index, age, growth hormone levels, diagnosis delay, tumor size, disease duration, treatment, disease status, and other comorbidities were analyzed. RESULTS: Eight (6.8%) of 117 patients were diagnosed with cancer. The incidence of overall (SIR = 3.29, 95% CI = 1.42-6.94), colorectal (SIR = 16.67, 95% CI = 4.45-42.67), and thyroid cancers (SIR = 14.29, 95% CI = 1.73-51.60) was increased, but that of lung cancer (SIR = 4.17, 95% CI = 0.50-15.05) was not. Diagnostic delay (10.1[8.6-14.3] vs 3.8[1.3-9.0]; P = .005) and duration of acromegaly (12.8[8.9-16.4] vs 5.6[2.3-10.9]; P = .008) were prolonged in the cancer group. Diabetes mellitus (odds ratio = 7.01, 95% CI = 1.23-39.99) was an independent risk factor for acromegaly with cancer. CONCLUSION: Acromegaly patients are at a higher risk of cancer and its association with diabetes mellitus. Considering the rarity of the disease, an Acromegaly Cancer Registry Center should be established in China as soon as possible.


Asunto(s)
Acromegalia , Diabetes Mellitus , Hormona de Crecimiento Humana , Neoplasias de la Tiroides , Humanos , Acromegalia/complicaciones , Acromegalia/epidemiología , Diagnóstico Tardío , Diabetes Mellitus/epidemiología , Factores de Riesgo
19.
BMC Pulm Med ; 23(1): 411, 2023 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-37898737

RESUMEN

OBJECTIVES: To examine the characteristics of blood lymphocyte subsets in dermatomyositis-interstitial lung disease (DM-ILD) inflicted patients with positive anti-melanoma differentiation-associated gene 5 (anti-MDA5), as well as its prognosis value in this set of patients. METHODS: Data were retrospectively collected from 253 DM-ILD patients from three hospitals in China between January 2016 to January 2021. Patients were grouped into anti-MDA5 antibody positive group (MDA5+ DM-ILD) and anti-MDA5 antibody negative group (MDA5- DM-ILD) based on myositis-specific autoantibody test results. Demographic characteristics, lymphocyte subsets patterns and other clinical features were compared between the two groups. The association of lymphocyte subsets with 180-day mortality was investigated using survival analysis in MDA5+ DM-ILD. RESULTS: Out of 253 eligible patients with DM-ILD, 59 patients were anti-MDA5+ and 194 were anti-MDA5-. Peripheral blood lymphocyte count, CD3+ count, percentage of CD3+, CD3+CD4+ count, and CD3+CD8+ count was lower in MDA5+ DM-ILD than in MDA5- DM-ILD- (all P < 0.001) as well as CD3-CD19+ count (P = 0.04). In MDA5+ DM-ILD, CD3+CD8+ count ≤ 49.22 cell/µL (HR = 3.81, 95%CI [1.20,12.14]) and CD3-CD19+ count ≤ 137.64 cell/µL (HR = 3.43, 95%CI [1.15,10.24]) were independent predictors of mortality. CD3+CD8+ count ≤ 31.38 cell/µL was associated with a higher mortality risk in all DM-ILD patients (HR = 8.6, 95%CI [2.12,31.44]) after adjusting for anti-MDA5 and other clinical characteristics. CONCLUSION: Significant lymphocytes decrease was observed in MDA5+ DM-ILD patients. CD3+CD8+ cell count was associated with worse prognosis in both MDA5+ DM-ILD and all DM-ILD patients.


Asunto(s)
Dermatomiositis , Enfermedades Pulmonares Intersticiales , Humanos , Pronóstico , Estudios Retrospectivos , Helicasa Inducida por Interferón IFIH1 , Enfermedades Pulmonares Intersticiales/complicaciones , Autoanticuerpos , Subgrupos Linfocitarios , Recuento de Linfocitos
20.
World J Surg Oncol ; 21(1): 357, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37986077

RESUMEN

BACKGROUND: Endometrial carcinoma (EC) is the second most common gynecological malignancy, and the differences between different pathological types are not entirely clear. Here, we retrospectively collected eligible EC patients to explore their differences regarding clinical characteristics and prognosis. METHODS: Five hundred seventy EC patients from the First Affiliated Hospital of Zhengzhou University were included. Prognostic factors were measured using the univariate/multivariate Cox models. Overall survival (OS) and progression-free survival (PFS) were the primary and secondary endpoints, respectively. RESULTS: In total, 396 patients with uterine endometrioid carcinoma (UEC), 106 patients with uterine serous carcinoma (USC), 34 patients with uterine mixed carcinoma (UMC), and 34 patients with uterine clear cell carcinoma (UCCC) were included. Comparison of baseline characteristics revealed patients diagnosed with UEC were younger, had more early clinical stage, and had lower incidence of menopause and lymph node metastasis. Compared to UEC, other pathological EC obtained more unfavorable OS (UCCC: HR = 12.944, 95%CI = 4.231-39.599, P < 0.001; USC: HR = 5.958, 95%CI = 2.404-14.765, P < 0.001; UMC: HR = 1.777, 95%CI = 0.209-15.114, P = 0.599) and PFS (UCCC: HR = 8.696, 95%CI = 1.972-38.354, P = 0.004; USC: HR = 4.131, 95%CI = 1.243-13.729, P = 0.021; UMC: HR = 5.356, 95%CI = 0.935-30.692, P = 0.060). Compared with UEC patients, the OS of UCCC patients in stage I-II and USC patients in stage III-IV were significantly worse, while UMC patients in stage I-II favored poorer PFS. The OS of UCCC patients receiving no postoperative adjuvant therapy or chemotherapy alone were significantly worse. CONCLUSIONS: The baseline characteristics of UEC and other rare EC types varied greatly, and the prognostic significance of different pathological types on EC patients depended on clinical tumor stages and therapeutic options.


Asunto(s)
Carcinoma , Neoplasias Endometriales , Neoplasias Uterinas , Femenino , Humanos , Estudios Retrospectivos , Estadificación de Neoplasias , Pronóstico , Neoplasias Endometriales/terapia , Neoplasias Endometriales/patología , Neoplasias Uterinas/patología , Carcinoma/patología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA