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1.
Circulation ; 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38686562

RESUMEN

BACKGROUND: Myocardial mitochondrial dysfunction underpins the pathogenesis of heart failure (HF), yet therapeutic options to restore myocardial mitochondrial function are scarce. Epigenetic modifications of mitochondrial DNA (mtDNA), such as methylation, play a pivotal role in modulating mitochondrial homeostasis. However, their involvement in HF remains unclear. METHODS: Experimental HF models were established through continuous angiotensin II and phenylephrine (AngII/PE) infusion or prolonged myocardial ischemia/reperfusion injury. The landscape of N6-methyladenine (6mA) methylation within failing cardiomyocyte mtDNA was characterized using high-resolution mass spectrometry and methylated DNA immunoprecipitation sequencing. A tamoxifen-inducible cardiomyocyte-specific Mettl4 knockout mouse model and adeno-associated virus vectors designed for cardiomyocyte-targeted manipulation of METTL4 (methyltransferase-like protein 4) expression were used to ascertain the role of mtDNA 6mA and its methyltransferase METTL4 in HF. RESULTS: METTL4 was predominantly localized within adult cardiomyocyte mitochondria. 6mA modifications were significantly more abundant in mtDNA than in nuclear DNA. Postnatal cardiomyocyte maturation presented with a reduction in 6mA levels within mtDNA, coinciding with a decrease in METTL4 expression. However, an increase in both mtDNA 6mA level and METTL4 expression was observed in failing adult cardiomyocytes, suggesting a shift toward a neonatal-like state. METTL4 preferentially targeted mtDNA promoter regions, which resulted in interference with transcription initiation complex assembly, mtDNA transcriptional stalling, and ultimately mitochondrial dysfunction. Amplifying cardiomyocyte mtDNA 6mA through METTL4 overexpression led to spontaneous mitochondrial dysfunction and HF phenotypes. The transcription factor p53 was identified as a direct regulator of METTL4 transcription in response to HF-provoking stress, thereby revealing a stress-responsive mechanism that controls METTL4 expression and mtDNA 6mA. Cardiomyocyte-specific deletion of the Mettl4 gene eliminated mtDNA 6mA excess, preserved mitochondrial function, and mitigated the development of HF upon continuous infusion of AngII/PE. In addition, specific silencing of METTL4 in cardiomyocytes restored mitochondrial function and offered therapeutic relief in mice with preexisting HF, irrespective of whether the condition was induced by AngII/PE infusion or myocardial ischemia/reperfusion injury. CONCLUSIONS: Our findings identify a pivotal role of cardiomyocyte mtDNA 6mA and the corresponding methyltransferase, METTL4, in the pathogenesis of mitochondrial dysfunction and HF. Targeted suppression of METTL4 to rectify mtDNA 6mA excess emerges as a promising strategy for developing mitochondria-focused HF interventions.

2.
Chem Rev ; 123(9): 6257-6358, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-36944098

RESUMEN

The oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) are core steps of various energy conversion and storage systems. However, their sluggish reaction kinetics, i.e., the demanding multielectron transfer processes, still render OER/ORR catalysts less efficient for practical applications. Moreover, the complexity of the catalyst-electrolyte interface makes a comprehensive understanding of the intrinsic OER/ORR mechanisms challenging. Fortunately, recent advances of in situ/operando characterization techniques have facilitated the kinetic monitoring of catalysts under reaction conditions. Here we provide selected highlights of recent in situ/operando mechanistic studies of OER/ORR catalysts with the main emphasis placed on heterogeneous systems (primarily discussing first-row transition metals which operate under basic conditions), followed by a brief outlook on molecular catalysts. Key sections in this review are focused on determination of the true active species, identification of the active sites, and monitoring of the reactive intermediates. For in-depth insights into the above factors, a short overview of the metrics for accurate characterizations of OER/ORR catalysts is provided. A combination of the obtained time-resolved reaction information and reliable activity data will then guide the rational design of new catalysts. Strategies such as optimizing the restructuring process as well as overcoming the adsorption-energy scaling relations will be discussed. Finally, pending current challenges and prospects toward the understanding and development of efficient heterogeneous catalysts and selected homogeneous catalysts are presented.

3.
J Am Chem Soc ; 146(11): 7178-7184, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38466344

RESUMEN

In the field of catalytic asymmetric synthesis, the less-treated path lies in oxidative catalytic asymmetric transformations. The hurdles of pinpointing the appropriate chemical oxidants and addressing their compatibility issues with catalysts and functionalities present significant challenges. Organic electrochemistry, employing traceless electrons for redox reactions, is underscored as a promising solution. However, the commonly used electrolysis in batch cells introduces its own set of challenges, hindering the advancement of electrochemical asymmetric catalysis. Here we introduce a microfluidic electrochemistry platform with single-pass continuous flow reactors that exhibits a wide-ranging applicability to various oxidative asymmetric catalytic transformations. This is exemplified through the sulfenylation of 1,3-dicarbonyls, dehydrogenative C-C coupling, and dehydrogenative alkene annulation processes. The unique properties of microfluidic electrochemical reactors not only eliminate the need for chemical oxidants but also enhance reaction efficiency and reduce the use of additives and electrolytes. These salient features of microfluidic electrochemistry expedite the discovery and development of oxidative asymmetric transformations. In addition, the continuous production facilitated by parallel single-pass reactors ensures straightforward reaction upscaling, removing the necessity for reoptimization across various scales, as evidenced by direct translation from milligram screening to hectogram asymmetric synthesis.

4.
Mol Cell Biochem ; 479(4): 993-1010, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37269411

RESUMEN

Radiotherapy is essential to cancer treatment, while it inevitably injures surrounding normal tissues, and bone tissue is one of the most common sites prone to irradiation. Bone marrow mesenchymal stem cells (BMMSCs) are sensitive to irradiation and the irradiated dysfunction of BMMSCs may be closely related to irradiation-induced bone damage. Macropahges play important role in regulating stem cell function, bone metabolic balance and irradiation response, but the effects of macrophages on irradiated BMMSCs are still unclear. This study aimed to investigate the role of macrophages and macrophage-derived exosomes in restoring irradiated BMMSCs function. The effects of macrophage conditioned medium (CM) and macrophage-derived exosomes on osteogenic and fibrogenic differentiation capacities of irradiated BMMSCs were detected. The key microribonucleic acids (miRNAs) and targeted proteins in exosomes were also determined. The results showed that irradiation significantly inhibited the proliferation of BMMSCs, and caused differentiation imbalance of BMMSCs, with decreased osteogenic differentiation and increased fibrogenic differentiation. M2 macrophage-derived exosomes (M2D-exos) inhibited the fibrogenic differentiation and promoted the osteogenic differentiation of irradiated BMMSCs. We identified that miR-142-3p was significantly overexpressed in M2D-exos and irradiated BMMSCs treated with M2D-exos. After inhibition of miR-142-3p in M2 macrophage, the effects of M2D-exos on irradiated BMMSCs differentiation were eliminated. Furthermore, transforming growth factor beta 1 (TGF-ß1), as a direct target of miR-142-3p, was significantly decreased in irradiated BMMSCs treated with M2D-exos. This study indicated that M2D-exos could carry miR-142-3p to restore the differentiation balance of irradiated BMMSCs by targeting TGF-ß1. These findings pave a new way for promising and cell-free method to treat irradiation-induced bone damage.


Asunto(s)
Exosomas , Células Madre Mesenquimatosas , MicroARNs , MicroARNs/genética , MicroARNs/metabolismo , Osteogénesis , Factor de Crecimiento Transformador beta1/metabolismo , Exosomas/metabolismo , Células Madre Mesenquimatosas/metabolismo , Macrófagos/metabolismo
5.
Circ Res ; 130(10): 1490-1506, 2022 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-35387487

RESUMEN

RATIONALE: Long-term exercise provides reliable cardioprotection via mechanisms still incompletely understood. Although traditionally considered a thermogenic tissue, brown adipose tissue (BAT) communicates with remote organs (eg, the heart) through its endocrine function. BAT expands in response to exercise, but its involvement in exercise cardioprotection remains undefined. OBJECTIVE: This study investigated whether small extracellular vesicles (sEVs) secreted by BAT and their contained microRNAs (miRNAs) regulate cardiomyocyte survival and participate in exercise cardioprotection in the context of myocardial ischemia/reperfusion (MI/R) injury. METHODS AND RESULTS: Four weeks of exercise resulted in a significant BAT expansion in mice. Surgical BAT ablation before MI/R weakened the salutary effects of exercise. Adeno-associated virus 9 vectors carrying short hairpin RNA targeting Rab27a (a GTPase required for sEV secretion) or control viruses were injected in situ into the interscapular BAT. Exercise-mediated protection against MI/R injury was greatly attenuated in mice whose BAT sEV secretion was suppressed by Rab27a silencing. Intramyocardial injection of the BAT sEVs ameliorated MI/R injury, revealing the cardioprotective potential of BAT sEVs. Discovery-driven experiments identified miR-125b-5p, miR-128-3p, and miR-30d-5p (referred to as the BAT miRNAs) as essential BAT sEV components for mediating cardioprotection. BAT-specific inhibition of the BAT miRNAs prevented their upregulation in plasma sEVs and hearts of exercised mice and attenuated exercise cardioprotection. Mechanistically, the BAT miRNAs cooperatively suppressed the proapoptotic MAPK (mitogen-associated protein kinase) pathway by targeting a series of molecules (eg, Map3k5, Map2k7, and Map2k4) in the signaling cascade. Delivery of BAT sEVs into hearts or cardiomyocytes suppressed MI/R-related MAPK pathway activation, an effect that disappeared with the combined use of the BAT miRNA inhibitors. CONCLUSIONS: The sEVs secreted by BAT participate in exercise cardioprotection via delivering the cardioprotective miRNAs into the heart. These results provide novel insights into the mechanisms underlying the BAT-cardiomyocyte interaction and highlight BAT sEVs and their contained miRNAs as alternative candidates for exercise cardioprotection.


Asunto(s)
Vesículas Extracelulares , MicroARNs , Daño por Reperfusión Miocárdica , Tejido Adiposo Pardo/metabolismo , Animales , Vesículas Extracelulares/metabolismo , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Daño por Reperfusión Miocárdica/genética , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/prevención & control , Miocitos Cardíacos/metabolismo , Condicionamiento Físico Animal
6.
Mol Biol Rep ; 51(1): 228, 2024 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-38281294

RESUMEN

BACKGROUND: The crucial role of STOML2 in tumor progression has been documented recently in various cancers. Previous studies have shown that STOML2 promoted cancer cell proliferation, but the underlying mechanism is not fully illustrated. METHODS AND RESULTS: The expression and clinical relevance of STOML2 in pan-cancer was analyzed by TIMER2 web platform in pan-cancer. The prognostic significance of STOML2 in HCC was evaluated utilizing KM curve and a nomogram model. Signaling pathways associated with STOML2 expression were discovered by GSEA. CCK-8 assay was performed to evaluate the proliferative capacity of HCC cells after manipulating STOML2 expression. Flow cytometry was utilized to analyze cell cycle progression. Results indicated that increased STOML2 expression in HCC linked to unfavorable clinical outcomes. Cell cycle and cell division related terms were enriched under conditions of elevated STOML2 expression via GSEA analysis. A notable decrease in cell proliferation was observed in MHCC97H with STOML2 knocked-down, accompanied by G1-phase arrest, up-regulation of p21, down-regulation of CyclinD1 and its regulatory factor MYC, while STOML2 overexpression in Huh7 showed the opposite results. These results indicated that STOML2 was responsible for HCC proliferation by regulating the expression level of MYC/cyclin D1 and p21. Furthermore, an inverse correlation was found between STOML2 expression and 5-FU sensitivity. CONCLUSIONS: STOML2 promotes cell cycle progression in HCC which is associated with activation of MYC/CyclinD1/p21 pathway, and modulates the response of HCC to 5-FU.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Fluorouracilo/farmacología , Transducción de Señal , Proliferación Celular , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica
7.
Bioorg Chem ; 143: 107001, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38101266

RESUMEN

Although the SARS-CoV-2 pandemic has ended, multiple sporadic cases still exist, posing a request for more antivirals. The main protease (Mpro) of SARS-CoV-2, a key enzyme for viral replication, is an attractive target for drug development. Here, we report the discovery of a new potent α-ketoamide-containing Mpro inhibitor, N-((R)-1-cyclohexyl-2-(((R)-3-methoxy-1-oxo-1-((1-(2-oxo-2-((thiazol-2-ylmethyl)amino)acetyl)cyclobutyl)amino)propan-2-yl)amino)-2-oxoethyl)-4,4-difluorocyclohexane-1-carboxamide (20j). This compound presented promising enzymatic inhibitory activity against SARS-CoV-2 Mpro with an IC50 value of 19.0 nM, and an excellent antiviral activity in cell-based assay with an EC50 value of 138.1 nM. This novel covalent inhibitor may be used as a lead compound for subsequent drug discovery against SARS-CoV-2.


Asunto(s)
COVID-19 , Proteasas 3C de Coronavirus , SARS-CoV-2 , Humanos , Antivirales/farmacología , Inhibidores de Proteasas/farmacología , Simulación del Acoplamiento Molecular
8.
J Clin Apher ; 39(1): e22103, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38098278

RESUMEN

The purpose of this retrospective study is to compare the efficacy and safety of the centrifugal separation therapeutic plasma exchange (TPE) using citrate anticoagulant (cTPEc) with membrane separation TPE using heparin anticoagulant (mTPEh) in liver failure patients. The patients treated by cTPEc were defined as cTPEc group and those treated by mTPEh were defined as mTPEh group, respectively. Clinical characteristics were compared between the two groups. Survival analyses of two groups and subgroups classified by the model for end-stage liver disease (MELD) score were performed by Kaplan-Meier method and were compared by the log-rank test. In this study, there were 51 patients in cTPEc group and 18 patients in mTPEh group, respectively. The overall 28-day survival rate was 76% (39/51) in cTPEc group and 61% (11/18) in mTPEh group (P > .05). The 90-day survival rate was 69% (35/51) in cTPEc group and 50% (9/18) in mTPEh group (P > .05). MELD score = 30 was the best cut-off value to predict the prognosis of patients with liver failure treated with TPE, in mTPEh group as well as cTPEc group. The median of total calcium/ionized calcium ratio (2.84, range from 2.20 to 3.71) after cTPEc was significantly higher than the ratio (1.97, range from 1.73 to 3.19) before cTPEc (P < .001). However, there was no significant difference between the mean concentrations of total calcium before cTPEc and at 48 h after cTPEc. Our study concludes that there was no statistically significant difference in survival rate and complications between cTPEc and mTPEh groups. The liver failure patients tolerated cTPEc treatment via peripheral vascular access with the prognosis similar to mTPEh. The prognosis in patients with MELD score < 30 was better than in patients with MELD score ≥ 30 in both groups. In this study, the patients with acute liver failure (ALF) and acute on chronic liver failure (ACLF) treated with cTPEc tolerated the TPE frequency of every other day without significant clinical adverse event of hypocalcemia with similar outcomes to the mTPEh treatment. For liver failure patients treated with cTPEc, close clinical observation and monitoring ionized calcium are necessary to ensure the patients' safety.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada , Enfermedad Hepática en Estado Terminal , Humanos , Insuficiencia Hepática Crónica Agudizada/terapia , Intercambio Plasmático/métodos , Estudios Retrospectivos , Heparina/uso terapéutico , Calcio , Enfermedad Hepática en Estado Terminal/terapia , Índice de Severidad de la Enfermedad , Anticoagulantes/uso terapéutico
9.
Sensors (Basel) ; 24(7)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38610255

RESUMEN

In recent years, biomedical optics technology has developed rapidly. The current widespread use of biomedical optics was made possible by the invention of optical instruments. The advantages of being non-invasive, portable, effective, low cost, and less susceptible to system noise have led to the rapid development of functional near-infrared spectroscopy (fNIRS) technology for hemodynamics detection, especially in the field of functional brain imaging. At the same time, laboratories and companies have developed various fNIRS-based systems. The safety, stability, and efficacy of fNIRS systems are key performance indicators. However, there is still a lack of comprehensive and systematic evaluation methods for fNIRS instruments. This study uses the fNIRS system developed in our laboratory as the test object. The test method established in this study includes system validation and performance testing to comprehensively assess fNIRS systems' reliability. These methods feature low cost and high practicality. Based on this study, existing or newly developed systems can be comprehensively and easily evaluated in the laboratory or workspace.


Asunto(s)
Tecnología Biomédica , Espectroscopía Infrarroja Corta , Humanos , Reproducibilidad de los Resultados , Encéfalo/diagnóstico por imagen , Laboratorios
10.
Am J Physiol Cell Physiol ; 324(2): C292-C306, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36440854

RESUMEN

Renal fibrosis is the final pathway for chronic kidney disease to end-stage renal failure. Noncoding RNAs have been reported to play a crucial role in renal fibrosis. Here, the effects of long noncoding RNA (lncRNA) nuclear-enriched abundant transcript 1 (NEAT1) and miR-31 on renal fibrosis and their regulatory mechanism were evaluated. RT-qPCR was used to assess NEAT1, miR-31, and RhoA levels. Western blot was performed to analyze the expression of fibrosis markers, RhoA, rho-related kinase (ROCK1), and connective tissue growth factor (CTGF). RNA immunoprecipitation (RIP), fluorescence in situ hybridization (FISH), and luciferase reporter assays verified the interaction between miR-31 and NEAT1 or RhoA. Renal fibrosis and injury were observed by Masson and hematoxylin and eosin (H&E) staining. The expression level of inflammatory cytokines was detected by ELISA. Immunohistochemistry (IHC) was performed to examine the expression levels of α-smooth muscle actin (α-SMA) and RhoA in renal tissues. We showed that NEAT1 was highly expressed, whereas miR-31 was decreased in renal fibrosis. NEAT1 was found to directly bind miR-31 to positively regulate RhoA expression. Furthermore, NEAT1 silencing inhibited renal fibrosis and inflammation and suppressed the RhoA/ROCK1 signaling pathway. However, knockdown of miR-31 could reverse these effects. NEAT1 silencing or overexpression of miR-31 alleviated renal fibrosis in vivo. In conclusion, NEAT1 accelerates renal fibrosis progression via negative regulation of miR-31 and the activation of RhoA/ROCK1 pathway, thereby upregulating the expression level of CTGF, providing a theoretical basis for treatment and prognostic evaluation of renal fibrosis.


Asunto(s)
Enfermedades Renales , MicroARNs , ARN Largo no Codificante , Humanos , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Hibridación Fluorescente in Situ , Fibrosis , Transducción de Señal , Apoptosis , Proteína de Unión al GTP rhoA/genética , Proteína de Unión al GTP rhoA/metabolismo , Quinasas Asociadas a rho/genética , Quinasas Asociadas a rho/metabolismo
11.
Bioorg Med Chem Lett ; 86: 129238, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-36924946

RESUMEN

The ongoing COVID-19 pandemic has led to massive infections and deaths and caused tremendous grief among the people. Although vaccines have played an important role in fighting COVID-19, the situation that the protective effect of current vaccines significantly decreases against mutated strains reminds us of the pressing need for developing effective antiviral therapeutics. The main protease (Mpro) is a key enzyme for SARS-CoV-2 viral replication and transcription and an attractive target for drug development. In this research, we report a new series of Mpro inhibitors containing 3-phenyl-1,2,4-oxadiazole. Structure-activity relationship (SAR) studies led to the discovery of the most active compound, 16d, which showed an IC50 value of 5.27 ± 0.26 µM. Collectively, we obtained a new small molecular inhibitor targeting SARS-CoV-2 Mpro, which contains a new scaffold. This compound could be taken as a lead compound for subsequent drug discovery against SARS-CoV-2.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Pandemias , Inhibidores de Proteasas/farmacología , Antivirales/farmacología , Simulación del Acoplamiento Molecular
12.
Acta Pharmacol Sin ; 44(10): 1989-2003, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37268711

RESUMEN

Patients with rheumatoid arthritis (RA) have a much higher incidence of cardiac dysfunction, which contributes to the high mortality rate of RA despite anti-arthritic drug therapy. In this study, we investigated dynamic changes in cardiac function in classic animal models of RA and examined the potential effectors of RA-induced heart failure (HF). Collagen-induced arthritis (CIA) models were established in rats and mice. The cardiac function of CIA animals was dynamically monitored using echocardiography and haemodynamics. We showed that cardiac diastolic and systolic dysfunction occurred in CIA animals and persisted after joint inflammation and that serum proinflammatory cytokine (IL-1ß, TNF-α) levels were decreased. We did not find evidence of atherosclerosis (AS) in arthritic animals even though cardiomyopathy was significant. We observed that an impaired cardiac ß1AR-excitation contraction coupling signal was accompanied by sustained increases in blood epinephrine levels in CIA rats. Furthermore, serum epinephrine concentrations were positively correlated with the heart failure biomarker NT-proBNP in RA patients (r2 = +0.53, P < 0.0001). In CIA mice, treatment with the nonselective ßAR blocker carvedilol (2.5 mg·kg-1·d-1, for 4 weeks) or the specific GRK2 inhibitor paroxetine (2.5 mg·kg-1·d-1, for 4 weeks) effectively rescued heart function. We conclude that chronic and persistent ß-adrenergic stress in CIA animals is a significant contributor to cardiomyopathy, which may be a potential target for protecting RA patients against HF.


Asunto(s)
Artritis Experimental , Artritis Reumatoide , Cardiomiopatías , Insuficiencia Cardíaca , Humanos , Ratones , Ratas , Animales , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/inducido químicamente , Roedores , Adrenérgicos/efectos adversos , Artritis Reumatoide/tratamiento farmacológico , Citocinas , Insuficiencia Cardíaca/tratamiento farmacológico , Epinefrina/efectos adversos
13.
Phytopathology ; 113(1): 21-30, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35918852

RESUMEN

Southern corn rust (SCR) caused by Puccinia polysora is one of the most devastating diseases in the world. In recent years, SCR has been upgraded from a minor to a major disease around the world, including in China. However, little is known about its population genetics and structure in China. In this study, we analyzed 288 isolates collected from various localities during 2017 in seven Chinese provinces: Guangxi, Guangdong, Anhui, Hunan, Shandong, Henan, and Shaanxi. The isolates were analyzed using nine microsatellite markers. The population structure, genetic diversity, and reproduction mode of P. polysora were investigated based on genotype data. Strong genotypic diversity was detected and clonal reproduction was dominant. The populations collected from the pathogen's winter-reproductive regions harbored more genotypes than those collected from the pathogen's epidemic regions. The spatial differences in genotypic richness, and evenness among the populations were significant, and showed a decreasing trend from south to north. Most isolates were clustered into two clonal groups. Two high-frequency multilocus genotypes (MLGs), MLG1 and MLG2, were widely distributed in all populations. Our analyses confirmed that P. polysora employed clone dispersal from the pathogen's winter-reproductive regions to the pathogen's epidemic regions, and in addition to the sources from the pathogen's winter-reproductive regions, the pathogen in Anhui and Hunan might also have other sources from areas such as Taiwan, China, or/and Southeast Asia, and the pathogen went through a genetic bottleneck during its dispersal. These findings provide initial insights into the reproduction mode and dispersal pathways of P. polysora in China.


Asunto(s)
Basidiomycota , Variación Genética , China , Enfermedades de las Plantas/genética , Basidiomycota/genética , Genotipo , Zea mays
14.
Ren Fail ; 45(2): 2254569, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37755153

RESUMEN

Coronary artery calcification (CAC) is common in dialysis patients and is associated with a higher risk of future cardiovascular events. Sodium thiosulfate (STS) is effective for calciphylaxis in dialysis patients; however, the influence of STS on CAC in dialysis patients remains unclear. This systematic review and meta-analysis were conducted to evaluate the effects of STS on CAC in patients undergoing dialysis. PubMed, Embase, Cochrane Library, CNKI, and Wanfang databases were searched from inception to 22 March 2023 for controlled studies comparing the influence of STS versus usual care without STS on CAC scores in dialysis patients. A random effects model incorporating the potential influence of heterogeneity was used to pool the results. Nine studies, including two non-randomized studies and seven randomized controlled trials, were included in the meta-analysis. Among these, 365 patients on dialysis were included in the study. Compared with usual care without STS, intravenous STS for 3-6 months was associated with significantly reduced CAC scores (mean difference [MD] = -180.17, 95% confidence interval [CI]: -276.64 to -83.70, p < 0.001, I2 = 0%). Sensitivity analysis limited to studies of patients on hemodialysis showed similar results (MD: -167.33, 95% CI: -266.57 to -68.09, p = 0.001; I2 = 0%). Subgroup analyses according to study design, sample size, mean age, sex, dialysis vintage of the patients, and treatment duration of STS also showed consistent results (p for subgroup differences all > 0.05). In conclusion, intravenous STS may be effective in attenuating CAC in dialysis patients.


Asunto(s)
Enfermedad de la Arteria Coronaria , Tiosulfatos , Calcificación Vascular , Humanos , Diálisis Renal , Tiosulfatos/uso terapéutico , Calcificación Vascular/prevención & control
15.
BMC Bioinformatics ; 23(1): 358, 2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-36042415

RESUMEN

BACKGROUND: Fractional vegetation coverage (FVC) is a crucial parameter in determining vegetation structure. Automatic measurement of FVC using digital images captured by mobile smart devices is a potential direction for future research on field survey methods in plant ecology, and this algorithm is crucial for accurate FVC measurement. However, there is a lack of insight into the influence of illumination on the accuracy of FVC measurements. Therefore, the main objective of this research is to assess the adaptiveness and performance of different algorithms under varying light conditions for FVC measurements and to deepen our understanding of the influence of illumination on FVC measurement. METHODS AND RESULTS: Based on a literature survey, we selected four algorithms that have been reported to have high accuracy in automatic FVC measurements. The first algorithm (Fun01) identifies green plants based on the combination of [Formula: see text], [Formula: see text], and [Formula: see text] ([Formula: see text], [Formula: see text], and [Formula: see text] are the actual pixel digital numbers from the images based on each RGB channel, [Formula: see text] is the abbreviation of the Excess Green index), the second algorithm (Fun02) is a decision tree that uses color properties to discriminate plants from the background, the third algorithm (Fun03) uses [Formula: see text] ([Formula: see text] is the abbreviation of the Excess Red index) to recognize plants in the image, and the fourth algorithm (Fun04) uses [Formula: see text] and [Formula: see text] to separate the plants from the background. [Formula: see text] is an algorithm used to determine a threshold to transform the image into a binary image for the vegetation and background. We measured the FVC of several surveyed quadrats using these four algorithms under three scenarios, namely overcast sky, solar forenoon, and solar noon. FVC values obtained using the Photoshop-assisted manual identification method were used as a reference to assess the accuracy of the four algorithms selected. Results indicate that under the overcast sky scenario, Fun01 was more accurate than the other algorithms and the MAPE (mean absolute percentage error), BIAS, relBIAS (relative BIAS), RMSE (root mean square error), and relRMSE (relative RMSE) are 8.68%, 1.3, 3.97, 3.13, and 12.33%, respectively. Under the scenario of the solar forenoon, Fun02 (decision tree) was more accurate than other algorithms, and the MAPE, BIAS, relBIAS, RMSE, and relRMSE are 22.70%, - 2.86, - 7.70, 5.00, and 41.23%. Under the solar noon scenario, Fun02 was also more accurate than the other algorithms, and the MAPE, BIAS, relBIAS, RMSE, and relRMSE are 20.60%, - 6.39, - 20.67, 7.30, and 24.49%, respectively. CONCLUSIONS: Given that each algorithm has its own optimal application scenario, among the four algorithms selected, Fun01 (the combination of [Formula: see text], [Formula: see text], and [Formula: see text]) can be recommended for measuring FVC on cloudy days. Fun02 (decision tree) is more suitable for measuring the FVC on sunny days. However, it considerably underestimates the FVC in most cases. We expect the findings of this study to serve as a useful reference for automatic vegetation cover measurements.


Asunto(s)
Algoritmos , Ecología , Plantas
16.
Inorg Chem ; 61(1): 657-663, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-34905335

RESUMEN

Crystal structure design based on known materials is an efficient strategy for exploring new compounds with evident second-harmonic-generation (SHG) effects. By the introduction of Rb+ ions into the 3D framework of Cu3NbS4, the new compound RbCu2NbS4 (space group Ama2) composed of [Cu22∞NbS4]- layers is obtained. The band gap of RbCu2NbS4 is 2.1 eV, indicating that this compound is a semiconductor. Band-structure calculations indicate that the electronic transition mainly occurs from the S 3p/Cu 3d to Nb 4d states. The intercalation of Rb+ ions induces a high degree of local distortion and symmetry reduction, which results in a dipole moment of 11.7 Debye for RbCu2NbS4. RbCu2NbS4 shows a moderate SHG response of 0.33 × AgGaS2 (particle size of 20-41 µm).

17.
Kidney Blood Press Res ; 47(3): 177-184, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35038705

RESUMEN

INTRODUCTION: Diabetic nephropathy (DN) is the leading cause of kidney failure worldwide. To explore the pathogenesis and effective biological target of DN is beneficial to seeking novel treatment strategies. OBJECTIVE: This study aimed to investigate the role of the lncRNA Dlx6os1/SOX6/EZH2 axis in DN progression. METHODS: PAS staining was performed to evaluate extracellular matrix accumulation; ELISA was carried out to assess the levels of urine microalbumin and blood glucose concentration; RT-qPCR was carried out to detect the levels of lncRNA Dlx6os1, TNF-α, IL-1ß, IL-6, SOX6, and EZH2. Western blot was performed to assess the levels of Col-IV, FN, TGF-ß1, and SOX6 proteins. RIP assay was carried out to verify the interaction between lncRNA Dlx6os1 and EZH2. ChIP-qPCR was conducted to verify the interaction between EZH2 and SOX6 promoter. RESULTS: Our results illustrated that lncRNA Dlx6os1 was highly expressed in DN mice and HG-induced SV40 MES13 cells. LncRNA Dlx6os1 knockdown inhibited HG-induced SV40 MES13 cell proliferation, fibrosis, and inflammatory cytokine release. LncRNA Dlx6os1 inhibited SOX6 expression by recruiting EZH2 in HG-SV40 MES13 cells, and SOX6 mediated the effects of lncRNA Dlx6os1 on proliferation, fibrosis, and inflammatory factor release of HG-induced SV40 MES13 cells. CONCLUSION: LncRNA Dlx6os1 accelerates the progression of DN by epigenetically repressing SOX6 via recruiting EZH2.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , ARN Largo no Codificante , Animales , Proliferación Celular , Nefropatías Diabéticas/patología , Proteína Potenciadora del Homólogo Zeste 2 , Fibrosis , Ratones , ARN Largo no Codificante/genética , Factores de Transcripción SOXD
18.
Sensors (Basel) ; 22(22)2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36433477

RESUMEN

Traffic flow prediction is a key issue in intelligent transportation systems. The growing trend in data disclosure has created more potential sources for the input for predictive models, posing new challenges to the prediction of traffic flow in the era of big data. In this study, the prediction of urban traffic flow was regarded as a spatiotemporal prediction problem, focusing on the traffic speed. A Graph LSTM (Long Short-Term Memory) Spatiotemporal Neural Network (GLSNN) model was constructed to perform a multi-scale spatiotemporal fusion prediction based on the multi-source input data. The GLSNN model consists of three parts: MS-LSTM, LZ-GCN, and LSTM-GRU. We used the MS-LSTM module to scale the traffic timing data, and then used the LZ-GCN network and the LSTM-GRU network to capture both the time and space dependencies. The model was tested on a real traffic dataset, and the experiment results verified the superior performance of the GLSNN model on both a high-precision and multi-scale prediction of urban traffic flow.


Asunto(s)
Redes Neurales de la Computación
19.
Mol Cell Biochem ; 476(10): 3551-3561, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34014438

RESUMEN

Vascular calcification is one of the most common effects of macrovascular complications in patients in aging with chronic kidney disease and diabetes. Previous studies showed that HOTAIR attenuated vascular calcification via the Wnt/ß-catenin-signaling pathway, yet the molecular mechanism has not been fully elucidated. This study aimed to identify the explicit molecular mechanism underlying HOTAIR regulated vascular calcification. In the phosphate (Pi)-induced calcification model of human aortic smooth muscle cells (HASMCs), we investigated whether HOTAIR was involved in the regulation of miR-126. The luciferase reporter was used to examine the effect of HOTAIR on miR-126 and miR-126 on Klotho 3'-UTR. Furthermore, we overexpressed Klotho to verify the regulation of Klotho on SIRT1, as well as their roles in mediating Pi-induced calcification in HASMCs via the Wnt/ß-catenin signaling pathway. Finally, the results were verified in an in vivo mice calcification model. Overexpression of HOTAIR reduced the expression of miR-126 in Pi-induced HASMCs. Additionally, knockdown of miR-126 increased SIRT1 expression by regulating Klotho expression. An increased level of Klotho inhibited Wnt/ß-catenin signaling pathway, which eventually attenuated Pi-induced HASMCs calcification. Luciferase reporter assay revealed that HOTAIR targeted miR-126 and miR-126 could directly target Klotho. Eventually, HOTAIR overexpression reversed Pi-induced calcium calcification in vivo mouse models. This study demonstrated that HOTAIR overexpression attenuated Pi-induced calcification by regulating the miR-126/Klotho/SIRT1 axis, thereby inhibiting the Wnt/ß-catenin signaling pathway. It provides new potential target genes for the clinical treatment of vascular calcification.


Asunto(s)
Glucuronidasa/metabolismo , Proteínas de la Membrana/metabolismo , MicroARNs/metabolismo , ARN Largo no Codificante/metabolismo , Sirtuina 1/metabolismo , Calcificación Vascular/metabolismo , Vía de Señalización Wnt , Animales , Línea Celular , Glucuronidasa/genética , Humanos , Proteínas Klotho , Masculino , Proteínas de la Membrana/genética , Ratones , MicroARNs/genética , ARN Largo no Codificante/genética , Sirtuina 1/genética , Calcificación Vascular/genética , Calcificación Vascular/patología
20.
Phytopathology ; 111(1): 96-107, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33026300

RESUMEN

Phytophthora infestans, the causal agent of the Irish Potato Famine in the 1840s, is one of the most destructive crop pathogens that threaten global food security. Host resistance (R) genes may help to control the disease, but recognition by through the gene products can be evaded by newly emerging isolates. Such isolates are dangerous as they may cause disease outbreaks under favorable conditions. However, our lack of knowledge about adaptation in these isolates jeopardizes an apt response to resistance breakdown. Here we performed genome and transcriptome sequencing of HB1501 and HN1602, two field isolates from distinct Chinese geographic regions. We found extensive polymorphisms in these isolates, including gene copy number variations, nucleotide polymorphisms, and gene expression changes. Effector encoding genes, which contribute to virulence, show distinct expression landscapes in P. infestans isolates HB1501 and HN1602. In particular, polymorphisms at multiple effectors required for recognition (Avr loci) enabled these isolates to overcome corresponding R gene based resistance. Although the isolates evolved multiple strategies to evade recognition, we experimentally verified that several R genes such as R8, RB, and Rpi-vnt1.1 remain effective against these isolates and are valuable to potato breeding in the future. In summary, rapid characterization of the adaptation in emerging field isolates through genomic tools inform rational agricultural management to prevent potential future epidemics.


Asunto(s)
Phytophthora infestans , Solanum tuberosum , Variaciones en el Número de Copia de ADN , Manejo de la Enfermedad , Phytophthora infestans/genética , Fitomejoramiento , Enfermedades de las Plantas
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