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1.
Arterioscler Thromb Vasc Biol ; 44(7): 1628-1645, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38813696

RESUMEN

BACKGROUND: Pericoronary epicardial adipose tissue (EAT) is a unique visceral fat depot that surrounds the adventitia of the coronary arteries without any anatomic barrier. Clinical studies have demonstrated the association between EAT volume and increased risks for coronary artery disease (CAD). However, the cellular and molecular mechanisms underlying the association remain elusive. METHODS: We performed single-nucleus RNA sequencing on pericoronary EAT samples collected from 3 groups of subjects: patients undergoing coronary bypass surgery for severe CAD (n=8), patients with CAD with concomitant type 2 diabetes (n=8), and patients with valvular diseases but without concomitant CAD and type 2 diabetes as the control group (n=8). Comparative analyses were performed among groups, including cellular compositional analysis, cell type-resolved transcriptomic changes, gene coexpression network analysis, and intercellular communication analysis. Immunofluorescence staining was performed to confirm the presence of CAD-associated subclusters. RESULTS: Unsupervised clustering of 73 386 nuclei identified 15 clusters, encompassing all known cell types in the adipose tissue. Distinct subpopulations were identified within primary cell types, including adipocytes, adipose stem and progenitor cells, and macrophages. CD83high macrophages and FOSBhigh adipocytes were significantly expanded in CAD. In comparison to normal controls, both disease groups exhibited dysregulated pathways and altered secretome in the primary cell types. Nevertheless, minimal differences were noted between the disease groups in terms of cellular composition and transcriptome. In addition, our data highlight a potential interplay between dysregulated circadian clock and altered physiological functions in adipocytes of pericoronary EAT. ANXA1 (annexin A1) and SEMA3B (semaphorin 3B) were identified as important adipokines potentially involved in functional changes of pericoronary EAT and CAD pathogenesis. CONCLUSIONS: We built a complete single-nucleus transcriptomic atlas of human pericoronary EAT in normal and diseased conditions of CAD. Our study lays the foundation for developing novel therapeutic strategies for treating CAD by targeting and modifying pericoronary EAT functions.


Asunto(s)
Tejido Adiposo , Enfermedad de la Arteria Coronaria , Pericardio , Transcriptoma , Humanos , Pericardio/metabolismo , Pericardio/patología , Femenino , Masculino , Persona de Mediana Edad , Enfermedad de la Arteria Coronaria/genética , Enfermedad de la Arteria Coronaria/patología , Enfermedad de la Arteria Coronaria/metabolismo , Anciano , Tejido Adiposo/metabolismo , Tejido Adiposo/patología , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Adipocitos/metabolismo , Adipocitos/patología , Enfermedades de las Válvulas Cardíacas/genética , Enfermedades de las Válvulas Cardíacas/patología , Enfermedades de las Válvulas Cardíacas/metabolismo , Enfermedades de las Válvulas Cardíacas/cirugía , Perfilación de la Expresión Génica/métodos , Estudios de Casos y Controles , Puente de Arteria Coronaria , Análisis de la Célula Individual , Macrófagos/metabolismo , Macrófagos/patología , Redes Reguladoras de Genes , Tejido Adiposo Epicárdico
2.
J Am Chem Soc ; 146(25): 17140-17149, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38864776

RESUMEN

Enantioselective three-component difunctionalization of alkenes with boron reagents represents an attractive strategy for assembling three-dimensional chiral organoboron compounds. However, regio- and enantiocontrol comprise the pivot challenges in these transformations, which predominantly require the use of activated conjugated alkenes. Herein, by utilizing various carbonyl directing groups, including amides, sulfinamides, ketones, and esters, we succeed in realizing a nickel-catalyzed 1,2-borylalkynylation of unactivated alkenes to enable the simultaneous incorporation of a boron entity and an sp-fragment across the double bond. The products contain boryl, alkynyl, and carbonyl functional groups with orthogonal synthetic reactivities, offering three handles for further derivatization to access valuable intermediates. The utility of this ligand-enabled asymmetric protocol has been highlighted through the late-stage decoration of drug-relevant molecules.

3.
Phys Rev Lett ; 132(1): 016601, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38242675

RESUMEN

Topological photonic states provide intriguing strategies for robust light manipulations, however, it remains challenging to perfectly excite these topological eigenstates due to their complicated mode profiles. In this work, we propose to realize the exact eigenmode of the topological edge states by supersymmetric (SUSY) structures. By adiabatically transforming the SUSY partner to its main topological structure, the edge modes can be perfectly excited with simple single-site input. We experimentally verify our strategy in integrated silicon waveguides in telecommunication wavelength, showing a broad working bandwidth. Moreover, a shortcut-to-adiabaticity strategy is further applied to speed up the adiabatic pump process by inverse-design approaches, thus enabling fast mode evolutions and leading to reduced device size. Our method is universal and beneficial to the topology-based or complex eigenmodes systems, ranging from photonics and microwaves to cold atoms and acoustics.

4.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(1): 191-198, 2024 Feb 25.
Artículo en Zh | MEDLINE | ID: mdl-38403621

RESUMEN

In recent years, bone implant materials such as titanium and titanium alloys have been widely used in the biomedical field due to their excellent mechanical properties and good biocompatibility. However, in clinical practice, bacterial adhesion to the material surface and postoperative infection issues may lead to implantation failure. Based on the antibacterial mechanism, this review elaborated on the antibacterial surface design of titanium implants from the aspects of anti-bacterial adhesion, contact sterilization and photocontrol sterilization. Surface modification of titanium or titanium-based alloy implants with different techniques can inhibit bacteria and promote osseointegration. Thus, the application range of multifunctional titanium-based implants in the field of orthopedics will be expanded.


Asunto(s)
Antibacterianos , Titanio , Titanio/farmacología , Propiedades de Superficie , Antibacterianos/farmacología , Prótesis e Implantes , Oseointegración , Aleaciones
5.
J Transl Med ; 21(1): 404, 2023 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-37344847

RESUMEN

BACKGROUND: Breast cancer brain metastases (BCBM) are the most fatal, with limited survival in all breast cancer distant metastases. These patients are deemed to be incurable. Thus, survival time is their foremost concern. However, there is a lack of accurate prediction models in the clinic. What's more, primary surgery for BCBM patients is still controversial. METHODS: The data used for analysis in this study was obtained from the SEER database (2010-2019). We made a COX regression analysis to identify prognostic factors of BCBM patients. Through cross-validation, we constructed XGBoost models to predict survival in patients with BCBM. Meanwhile, a BCBM cohort from our hospital was used to validate our models. We also investigated the prognosis of patients treated with surgery or not, using propensity score matching and K-M survival analysis. Our results were further validated by subgroup COX analysis in patients with different molecular subtypes. RESULTS: The XGBoost models we created had high precision and correctness, and they were the most accurate models to predict the survival of BCBM patients (6-month AUC = 0.824, 1-year AUC = 0.813, 2-year AUC = 0.800 and 3-year survival AUC = 0.803). Moreover, the models still exhibited good performance in an externally independent dataset (6-month: AUC = 0.820; 1-year: AUC = 0.732; 2-year: AUC = 0.795; 3-year: AUC = 0.936). Then we used Shiny-Web tool to make our models be easily used from website. Interestingly, we found that the BCBM patients with an annual income of over USD$70,000 had better BCSS (HR = 0.523, 95%CI 0.273-0.999, P < 0.05) than those with less than USD$40,000. The results showed that in all distant metastasis sites, only lung metastasis was an independent poor prognostic factor for patients with BCBM (OS: HR = 1.606, 95%CI 1.157-2.230, P < 0.01; BCSS: HR = 1.698, 95%CI 1.219-2.365, P < 0.01), while bone, liver, distant lymph nodes and other metastases were not. We also found that surgical treatment significantly improved both OS and BCSS in BCBM patients with the HER2 + molecular subtypes and was beneficial to OS of the HR-/HER2- subtype. In contrast, surgery could not help BCBM patients with HR + /HER2- subtype improve their prognosis (OS: HR = 0.887, 95%CI 0.608-1.293, P = 0.510; BCSS: HR = 0.909, 95%CI 0.604-1.368, P = 0.630). CONCLUSION: We analyzed the clinical features of BCBM patients and constructed 4 machine-learning prognostic models to predict their survival. Our validation results indicate that these models should be highly reproducible in patients with BCBM. We also identified potential prognostic factors for BCBM patients and suggested that primary surgery might improve the survival of BCBM patients with HER2 + and triple-negative subtypes.


Asunto(s)
Neoplasias Encefálicas , Neoplasias de la Mama , Modelos Estadísticos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/cirugía , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Aprendizaje Automático , Pronóstico , Reproducibilidad de los Resultados , Análisis de Supervivencia
6.
J Med Virol ; 95(4): e28722, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37185860

RESUMEN

In contemporary literature, little attention has been paid to the association between coronavirus disease-2019 (COVID-19) and cancer risk. We performed the Mendelian randomization (MR) to investigate the causal associations between the three types of COVID-19 exposures (critically ill COVID-19, hospitalized COVID-19, and respiratory syndrome coronavirus 2 (SARS-CoV-2) infection) and 33 different types of cancers of the European population. The results of the inverse-variance-weighted model indicated that genetic liabilities to critically ill COVID-19 had suggestive causal associations with the increased risk for HER2-positive breast cancer (odds ratio [OR] = 1.0924; p-value = 0.0116), esophageal cancer (OR = 1.0004; p-value = 0.0226), colorectal cancer (OR = 1.0010; p-value = 0.0242), stomach cancer (OR = 1.2394; p-value = 0.0331), and colon cancer (OR = 1.0006; p-value = 0.0453). The genetic liabilities to hospitalized COVID-19 had suggestive causal associations with the increased risk for HER2-positive breast cancer (OR = 1.1096; p-value = 0.0458), esophageal cancer (OR = 1.0005; p-value = 0.0440) as well as stomach cancer (OR = 1.3043; p-value = 0.0476). The genetic liabilities to SARS-CoV-2 infection had suggestive causal associations with the increased risk for stomach cancer (OR = 2.8563; p-value = 0.0019) but with the decreasing risk for head and neck cancer (OR = 0.9986, p-value = 0.0426). The causal associations of the above combinations were robust through the test of heterogeneity and pleiotropy. Together, our study indicated that COVID-19 had causal effects on cancer risk.


Asunto(s)
Neoplasias de la Mama , COVID-19 , Neoplasias Esofágicas , Neoplasias Gástricas , Humanos , Femenino , SARS-CoV-2 , Enfermedad Crítica , Análisis de la Aleatorización Mendeliana , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple
7.
EMBO Rep ; 22(11): e52389, 2021 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-34569705

RESUMEN

The migratory cardiac neural crest cells (CNCCs) contribute greatly to cardiovascular development. A thorough understanding of the cell lineages, developmental chronology, and transcriptomic states of CNCC derivatives during normal development is essential for deciphering the pathogenesis of CNCC-associated congenital anomalies. Here, we perform single-cell transcriptomic sequencing of 34,131 CNCC-derived cells in mouse hearts covering eight developmental stages between E10.5 and P7. We report the presence of CNCC-derived mural cells that comprise pericytes and microvascular smooth muscle cells (mVSMCs). Furthermore, we identify the transition from the CNCC-derived pericytes to mVSMCs and the key regulators over the transition. In addition, our data support that many CNCC derivatives had already committed or differentiated to a specific lineage when migrating into the heart. We explore the spatial distribution of some critical CNCC-derived subpopulations with single-molecule fluorescence in situ hybridization. Finally, we computationally reconstruct the differentiation path and regulatory dynamics of CNCC derivatives. Our study provides novel insights into the cell lineages, developmental chronology, and regulatory dynamics of CNCC derivatives during development.


Asunto(s)
Corazón , Cresta Neural , Transcriptoma , Animales , Diferenciación Celular , Corazón/crecimiento & desarrollo , Hibridación Fluorescente in Situ , Ratones , Cresta Neural/citología , Análisis de la Célula Individual
8.
Fish Shellfish Immunol ; 138: 108834, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37207885

RESUMEN

The present study was conducted to investigate the effects of dietary Coenzyme Q10 (CoQ10) on the growth performance, body composition, digestive enzyme activity, antioxidant capacity, intestinal histology, immune-antioxidant gene expression and disease resistance of juvenile European eel (Anguilla anguilla). Fish were fed a diet supplemented with CoQ10 at concentrations of 0, 40, 80 and 120 mg/kg for 56 days. The results indicated that dietary CoQ10 supplementation did not significantly affect final body weight (FBW), survival rate (SR), weight gain (WG), feed rate (FR), viscerosomatic index (VSI) or hepatosomatic index (HSI) among all experimental groups. However, the highest FBW, WG and SR were found in the 120 mg/kg CoQ10 group. Dietary 120 mg/kg CoQ10 markedly improved feed efficiency (FE) and the protein efficiency ratio (PER). The crude lipid in the body and triglycerides (TG) and total cholesterol (TC) in serum were obviously lower in the 120 mg/kg CoQ10 group than in the control group. For digestive enzymes, protease activity in the intestine was markedly boosted in the 120 mg/kg CoQ10 group. The serum activities of SOD, CAT and GST in the 120 mg/kg CoQ10 group were significantly higher than those in the control group. Dietary 120 mg/kg CoQ10 efficiently enhanced superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione S-transferase (GST) activities in the liver, while the malondialdehyde (MDA) content was significantly decreased. No significant histological changes in the liver were identified in any group. Dietary supplementation with 120 mg/kg CoQ10 improved antioxidant capacity and immunity by upregulating the expression of cyp1a, sod, gst, lysC, igma1, igmb1 and irf3 in the liver. Furthermore, the cumulative survival rate of juvenile European eel against challenge with Aeromonas hydrophila was significantly elevated in the 80 and 120 mg/kg CoQ10 supplemented groups. Conclusively, our study suggested that supplementing the diet of juvenile European eel with CoQ10 at a concentration of 120 mg/kg could promote their feed utilization, fat reduction, antioxidant capacity, digestibility, immune-antioxidant gene expression and resistance to Aeromonas hydrophila without negative effects on fish health status.


Asunto(s)
Anguilla , Enfermedades de los Peces , Animales , Antioxidantes/metabolismo , Aeromonas hydrophila/fisiología , Anguilla/metabolismo , Dieta/veterinaria , Suplementos Dietéticos , Resistencia a la Enfermedad , Superóxido Dismutasa , Alimentación Animal/análisis
9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 40(4): 792-798, 2023 Aug 25.
Artículo en Zh | MEDLINE | ID: mdl-37666771

RESUMEN

Sodium alginate (SA) is a kind of natural polymer material extracted from kelp, which has excellent biocompatibility, non-toxicity, biodegradability and abundant storage capacity. The formation condition of sodium alginate gel is mild, effectively avoiding the inactivation of active substances. After a variety of preparation methods, sodium alginate microspheres are widely used in the fields of biomaterials and tissue engineering. This paper reviewed the common methods of preparing alginate microspheres, including extrusion, emulsification, electrostatic spraying, spray drying and coaxial airflow, and discussed their applications in biomedical fields such as bone repair, hemostasis and drug delivery.


Asunto(s)
Alginatos , Procedimientos de Cirugía Plástica , Materiales Biocompatibles , Sistemas de Liberación de Medicamentos , Microesferas
10.
Angew Chem Int Ed Engl ; 62(37): e202304740, 2023 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-37212541

RESUMEN

Selective structural modification of amino acids and peptides is a central strategy in organic chemistry, chemical biology but also in pharmacology and material science. In this context, the formation of tetrazole rings, known to possess significant therapeutic properties, would expand the chemical space of unnatural amino acids but has received less attention. In this study, we demonstrated that the classic unimolecular Wolff rearrangement of α-amino acid-derived diazoketones could be replaced by a faster intermolecular cycloaddition reaction with aryldiazonium salts under identical practical conditions. This strategy provides an efficient synthetic platform that could transform proteinogenic α-amino acids into a plethora of unprecedented tetrazole-decorated amino acid derivatives with preservation of the stereocenters. Density functional theory studies shed some light on the reaction mechanism and provided information regarding the origins of the chemo- and regioselectivity. Furthermore, this diazo-cycloaddition protocol was applied to construct tetrazole-modified peptidomimetics and drug-like amino acid derivatives.


Asunto(s)
Aminoácidos , Plata , Aminoácidos/química , Reacción de Cicloadición , Sales (Química) , Péptidos , Tetrazoles/química , Catálisis
11.
Circ Res ; 126(7): 811-821, 2020 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-32078439

RESUMEN

RATIONALE: Transposition of the great arteries (TGA) is one of the most severe types of congenital heart diseases. Understanding the clinical characteristics and pathogenesis of TGA is, therefore, urgently needed for patient management of this severe disease. However, the clinical characteristics and genetic cause underlying TGA remain largely unexplored. OBJECTIVE: We sought to systematically examine the clinical characteristics and genetic cause for isolated nonsyndromic TGA. METHODS AND RESULTS: We recruited 249 patients with TGA (66 family trios) and performed whole-exome sequencing. The incidence of patent ductus arteriosus in dextro-TGA (52.7%) and dextrocardia/mesocardia in congenitally corrected TGA (32.8%) were significantly higher than that in other subtypes. A high prevalence of bicuspid pulmonic valve (9.6%) was observed in patients with TGA. Similar results were observed in a replication group of TGA (n=132). Through a series of bioinformatics filtering steps, we obtained 82 candidate genes harboring potentially damaging de novo, loss of function, compound heterozygous, or X-linked recessive variants. Established congenital heart disease-causing genes, such as FOXH1, were found among the list of candidate genes. A total of 19 ciliary genes harboring rare potentially damaging variants were also found; for example, DYNC2LI1 with a de novo putatively damaging variant. The enrichment of ciliary genes supports the roles of cilia in the pathogenesis of TGA. In total, 33% of the TGA probands had >1 candidate gene hit by putatively deleterious variants, suggesting that a portion of the TGA cases were probably affected by oligogenic or polygenic inheritance. CONCLUSIONS: The findings of clinical characteristic analyses have important implications for TGA patient stratification. The results of genetic analyses highlight the pathogenic role of ciliary genes and a complex genetic architecture underlying TGA.


Asunto(s)
Cilios/metabolismo , Exoma/genética , Predisposición Genética a la Enfermedad/genética , Mutación Missense , Transposición de los Grandes Vasos/genética , Secuencia de Aminoácidos , Secuencia de Bases , Estudios de Casos y Controles , Dineínas Citoplasmáticas/genética , Femenino , Humanos , Masculino , Homología de Secuencia de Aminoácido , Secuenciación del Exoma/métodos
12.
Int J Med Sci ; 19(7): 1173-1183, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35919820

RESUMEN

Backgrounds: The immunonutritional index showed great potential for predicting postoperative complications in various malignant diseases, while risk assessment based on machine learning (ML) methods is becoming popular in clinical practice. Early detection and prevention for postoperative anastomotic leakage (AL) play an important role in prognosis improvement among patients with gastric cancer (GC). Methods: This retrospective study included 297 patients with gastric cancer receiving gastrectomy between 2018 and 2021 in general surgery department of Xinhua Hospital. Perioperative clinical variables were collected to evaluate the predictive value for postoperative AL with 5 ML models. Then, AUROC was applied to identify the optimal perioperative clinical index and ML model for predicting postoperative AL. Results: The incidence of postoperative AL was 6.1% (n=18). After the training of 5 ML classification models, we found that immunonutritional index had significantly better classification ability than inflammatory or nutritional index alone separately (AUROC=0.87 vs. 0.83, P=0.01; AUROC=0.87 vs. 0.68, P<0.01). Next, we found that support vector machine (SVM), one of the ML methods, with selected immunonutritional index showed significantly greater classification ability than optimal univariant parameter [CRP on postoperative day 4 (AUROC=0.89 vs.0.86, P=0.02)]. Also, statistical analysis revealed multiple variables with significant relevance to postoperative AL, including serum CRP and albumin on postoperative day 4, NLR and SII etc. Conclusion: This study showed that perioperative immunonutritional index could act as an indicator for postoperative AL. Also, ML methods could significantly enhance the classification ability, and therefore, could be applied as a powerful tool for postoperative risk assessment for patients with GC.


Asunto(s)
Fuga Anastomótica , Neoplasias Gástricas , Fuga Anastomótica/diagnóstico , Fuga Anastomótica/epidemiología , Fuga Anastomótica/etiología , Correlación de Datos , Gastrectomía/efectos adversos , Humanos , Aprendizaje Automático , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Neoplasias Gástricas/cirugía
13.
Chemistry ; 27(15): 4817-4838, 2021 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-33034923

RESUMEN

Continuous-flow multi-step synthesis takes the advantages of microchannel flow chemistry and may transform the conventional multi-step organic synthesis by using integrated synthetic systems. To realize the goal, however, innovative chemical methods and techniques are urgently required to meet the significant remaining challenges. In the past few years, by using green reactions, telescoped chemical design, and/or novel in-line separation techniques, major and rapid advancement has been made in this direction. This minireview summarizes the most recent reports (2017-2020) on continuous-flow synthesis of functional molecules. Notably, several complex active pharmaceutical ingredients (APIs) have been prepared by the continuous-flow approach. Key technologies to the successes and remaining challenges are discussed. These results exemplified the feasibility of using modern continuous-flow chemistry for complex synthetic targets, and bode well for the future development of integrated, automated artificial synthetic systems.

14.
J Org Chem ; 85(16): 10872-10883, 2020 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-32691600

RESUMEN

The general synthesis of fully substituted N2-aryl-1,2,3-triazoles is hitherto challenging compared with that of the N1-aryl counterparts. Herein, we describe a Cu-catalyzed annulation reaction of azirines and aryldiazonium salts. This regiospecific method allows access to a broad spectrum of tri-carbo N2-aryl-1,2,3-triazoles substituted with diverse aryl and alkyl moieties. Its utility is highlighted by the synthesis of several triazole precursors applicable in drug discovery, as well as novel chiral binaphthyl ligands bearing triazole moieties.

15.
BMC Plant Biol ; 18(1): 261, 2018 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-30373525

RESUMEN

BACKGROUND: Plants have evolved excellent ability of flexibly regulating the growth of organs to adapt to changing environment, for example, the modulation of lateral root development in response to environmental stresses. Despite of fundamental discovery that some microRNAs are involved in this process, the molecular mechanisms of how these microRNAs work together are still largely unknown. RESULTS: Here we show that miR390 induced by auxin promotes lateral root growth in rice. However, this promotion can be suppressed by miR393, which is induced by various stresses and ABA (Abscisic Acid). Results that miR393 responded to ABA stronger and earlier than other stresses implied that ABA likely is authentic factor for inducing miR393. The transgenic lines respectively over-expressing miR393 and OsTAS3a (Oryza sativa Trans-Acting Short RNA precursor 3a) displayed opposite phenotypes in lateral root growth. MiR390 was found to be dominantly expressed at lateral root primordia and roots tips while miR393 mainly expressed in the base part of roots at very low level. When miR393 was up-regulated by various stresses, miR390 expression level fell down. However, the risen expression level of miR390 induced by auxin didn't affect the expression of miR393 and its target OsTIR1 (Transport Inhibitor Response 1). Together with analysis of the two transgenic lines, we provide a model of how the growth of lateral roots in rice is regulated distinctively by the 2 microRNAs. CONCLUSION: We propose that miR390 induced by auxin triggers the lateral root growth under normal growth conditions, meanwhile miR393 just lurks as a potentially regulative role; Once plants suffer from stresses, miR393 will be induced to negatively regulate miR390-mediated growth of lateral roots in rice.


Asunto(s)
MicroARNs/genética , Oryza/crecimiento & desarrollo , Oryza/genética , Raíces de Plantas/crecimiento & desarrollo , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacología , Sequías , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Ácidos Indolacéticos/metabolismo , Metales Pesados/toxicidad , Oryza/efectos de los fármacos , Raíces de Plantas/genética , Plantas Modificadas Genéticamente , ARN de Planta/genética
16.
Mol Ecol ; 27(24): 5088-5103, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30411828

RESUMEN

Edaphic conditions are important determinants of plant fitness. While much has been learnt in recent years about plant adaptation to heavy metal contaminated soils, the genomic basis underlying adaptation to calcareous and siliceous substrates remains largely unknown. We performed a reciprocal germination experiment and whole-genome resequencing in natural calcareous and siliceous populations of diploid Arabidopsis lyrata to test for edaphic adaptation and detect signatures of selection at loci associated with soil-mediated divergence. In parallel, genome scans on respective diploid ecotypes from the Arabidopsis arenosa species complex were undertaken, to search for shared patterns of adaptive genetic divergence. Soil ecotypes of A. lyrata display significant genotype-by-treatment responses for seed germination. Sequence (SNPs) and copy-number variants (CNVs) point towards loci involved in ion transport as the main targets of adaptive genetic divergence. Two genes exhibiting high differentiation among soil types in A. lyrata further share trans-specific single nucleotide polymorphisms with A. arenosa. This work applies experimental and genomic approaches to study edaphic adaptation in A. lyrata and suggests that physiological response to elemental toxicity and deficiency underlies the evolution of calcareous and siliceous ecotypes. The discovery of shared adaptive variation between sister species indicates that ancient polymorphisms contribute to adaptive evolution.


Asunto(s)
Adaptación Fisiológica/genética , Arabidopsis/genética , Suelo/química , Arabidopsis/fisiología , Variaciones en el Número de Copia de ADN , Ecotipo , Islas Genómicas , Genotipo , Metales Pesados , Modelos Genéticos , Polimorfismo de Nucleótido Simple , Selección Genética
17.
J Org Chem ; 83(18): 10898-10907, 2018 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-30110165

RESUMEN

An efficient chromium(III) chloride-catalyzed Michael-type reaction of water or alcohol with α,ß-unsaturated ketones is developed. A variety of α,ß-unsaturated ketones effectively reacted with either water or alcohols to give the corresponding ß-hydroxyl ketones or ß-alkoxyl ketones in modest to high yields with excellent compatibility to various functional groups. The approach was further utilized for the preparation of synthetically useful compounds containing tetrahydrofuran skeleton.

18.
J Org Chem ; 81(19): 9326-9336, 2016 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-27617346

RESUMEN

A practical intramolecular C-H functionalization reaction of N-aryl enamines has been carried out with molecular iodine (I2) as the sole oxidant in the presence of copper iodide (CuI). The efficient and versatile synthetic method described here is compatible with both N-heteroaryl and N-aryl substituted enamines and produces diverse imidazo[1,2-a]pyridine and indole derivatives via I2-mediated oxidative C-N and C-C bond formation, respectively. This ligand-free C-H functionalization methodology also works well with crude enamines, which allows for the sequential synthesis of the products directly from arylamines and ketones (or alkynes) without purification of the enamine intermediates.

19.
J Org Chem ; 79(3): 1254-64, 2014 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-24417351

RESUMEN

A copper(I)-catalyzed synthesis of substituted dihydropyrimidin-4-ones from propargyl amides via the formation of ketenimine intermediate has been successfully developed; the synthesis afforded good isolated yields (80-95%). The mild reaction conditions at room temperature allow the reaction to proceed to completion in a few hours without altering the stereochemistry. Further, by involving a variety of reactive nucleophiles, the obtained substituted dihydropyrimidin-4-ones were elegantly transformed into the corresponding ß- and ß(3)-amino acid analogues.


Asunto(s)
Aminoácidos/síntesis química , Cobre/química , Pargilina/análogos & derivados , Pargilina/química , Pirimidinonas/síntesis química , Aminoácidos/química , Catálisis , Estructura Molecular , Pirimidinonas/química , Estereoisomerismo
20.
Colloids Surf B Biointerfaces ; 239: 113942, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38729022

RESUMEN

Myocardial infarction (MI) stands out as a highly lethal disease that poses a significant threat to global health. Worldwide, heart failure resulting from MI remains a leading cause of human mortality. Mesenchymal stem cell (MSC) therapy has emerged as a promising therapeutic approach, leveraging its intrinsic healing properties. Nevertheless, pervasive issues, including a low cell retention rate, suboptimal survival rate, and incomplete differentiation of MSCs, present formidable challenges for further research. The introduction and advancement of biomaterials have offered a novel avenue for the exploration of MSC therapy in MI, marking considerable progress thus far. Notably, hydrogels, among the representative biomaterials, have garnered extensive attention within the biomedical field. This review delves into recent advancements, specifically focusing on the application of hydrogels to augment MSC therapy for cardiac tissue regeneration in MI.


Asunto(s)
Hidrogeles , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Infarto del Miocardio , Infarto del Miocardio/terapia , Infarto del Miocardio/patología , Células Madre Mesenquimatosas/citología , Humanos , Hidrogeles/química , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología
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