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1.
Int J Mol Sci ; 25(13)2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-39000240

RESUMEN

GAI-RGA-and-SCR (GRAS) transcription factors can regulate many biological processes such as plant growth and development and stress defense, but there are few related studies in sugar beet. Salt stress can seriously affect the yield and quality of sugar beet (Beta vulgaris). Therefore, this study used bioinformatics methods to identify GRAS transcription factors in sugar beet and analyzed their structural characteristics, evolutionary relationships, regulatory networks and salt stress response patterns. A total of 28 BvGRAS genes were identified in the whole genome of sugar beet, and the sequence composition was relatively conservative. According to the topology of the phylogenetic tree, BvGRAS can be divided into nine subfamilies: LISCL, SHR, PAT1, SCR, SCL3, LAS, SCL4/7, HAM and DELLA. Synteny analysis showed that there were two pairs of fragment replication genes in the BvGRAS gene, indicating that gene replication was not the main source of BvGRAS family members. Regulatory network analysis showed that BvGRAS could participate in the regulation of protein interaction, material transport, redox balance, ion homeostasis, osmotic substance accumulation and plant morphological structure to affect the tolerance of sugar beet to salt stress. Under salt stress, BvGRAS and its target genes showed an up-regulated expression trend. Among them, BvGRAS-15, BvGRAS-19, BvGRAS-20, BvGRAS-21, LOC104892636 and LOC104893770 may be the key genes for sugar beet's salt stress response. In this study, the structural characteristics and biological functions of BvGRAS transcription factors were analyzed, which provided data for the further study of the molecular mechanisms of salt stress and molecular breeding of sugar beet.


Asunto(s)
Beta vulgaris , Regulación de la Expresión Génica de las Plantas , Filogenia , Proteínas de Plantas , Estrés Salino , Factores de Transcripción , Beta vulgaris/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Estrés Salino/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Redes Reguladoras de Genes , Sintenía
2.
BMC Ophthalmol ; 23(1): 232, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37221461

RESUMEN

BACKGROUND: To evaluate the predictive effect of TCED-HFV grading and imaging biomarkers on anti-vascular endothelial growth factor (anti-VEGF) treatment in diabetic macular edema (DME). METHODS: 81 eyes of 81 DME patients who were treated with anti-VEGF were included in this retrospective cohort study. All patients underwent a comprehensive ophthalmic examination at baseline and follow-up, including best-corrected visual acuity (BCVA), fundus photography, and spectral domain-optical coherence tomography (SD-OCT). Baseline imaging biomarkers were qualitatively and quantitatively graded according to the TCED-HFV classification protocol, and DME was divided into early stage, advanced stage, severe stage, and atrophy stage. RESULTS: Six months post treatment, central subfield thickness (CST) in 49 eyes (60.5%) had decreased by 10% from baseline, 30 eyes (37.0%) had achieved CST < 300 µm, and 45 eyes (55.6%) had BCVA improved by more than five letters. Multivariate regression analysis revealed that eyes with baseline CST ≥ 390 µm had a higher probability of ≥ 10% reduction in CST from baseline, and eyes with abundant hyperreflective dots (HRD) had a lower probability of 10% reduction in CST (all P < 0.05). Eyes with vitreomacular traction (VMT) or epiretinal membrane (ERM) at baseline were less likely to reach the end point of CST < 300 µm (P < 0.05). BCVA increases of more than five letters were less likely in eyes with baseline BCVA ≥ 69 letters, complete or partial destruction of ellipsoid zone (EZ) at baseline (all P < 0.05). TCED-HFV staging was negatively correlated with BCVA at both baseline and 6 months (Kendall's tau-b=-0.39 and - 0.55, all P < 0.01). TCED-HFV staging was positively correlated with CST at 6 months (Kendall's tau-b = 0.19, P = 0.049) and negatively correlated with the reduction of CST (Kendall's tau-b=-0.32, P < 0.01). CONCLUSION: The TCED-HFV grading protocol facilitates a comprehensive assessment of DME severity, standardizes the grading of multiple imaging biomarkers, and predicts the anatomical and functional outcomes of anti-VEGF treatment.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Humanos , Estudios Retrospectivos , Ojo , Biomarcadores
4.
Bioinformatics ; 27(5): 611-8, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-21233169

RESUMEN

MOTIVATION: With the advancements of next-generation sequencing technology, it is now possible to study samples directly obtained from the environment. Particularly, 16S rRNA gene sequences have been frequently used to profile the diversity of organisms in a sample. However, such studies are still taxed to determine both the number of operational taxonomic units (OTUs) and their relative abundance in a sample. RESULTS: To address these challenges, we propose an unsupervised Bayesian clustering method termed Clustering 16S rRNA for OTU Prediction (CROP). CROP can find clusters based on the natural organization of data without setting a hard cut-off threshold (3%/5%) as required by hierarchical clustering methods. By applying our method to several datasets, we demonstrate that CROP is robust against sequencing errors and that it produces more accurate results than conventional hierarchical clustering methods. AVAILABILITY AND IMPLEMENTATION: Source code freely available at the following URL: http://code.google.com/p/crop-tingchenlab/, implemented in C++ and supported on Linux and MS Windows.


Asunto(s)
Teorema de Bayes , Análisis por Conglomerados , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN/métodos , Biología Computacional/métodos , Humanos , Metagenoma , Modelos Estadísticos , Piel/microbiología
5.
Bioorg Med Chem Lett ; 21(1): 423-6, 2011 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-21074992
6.
Bioorg Med Chem Lett ; 21(1): 417-22, 2011 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-21074993

RESUMEN

A novel series of (E)-1-((2-(1-methyl-1H-imidazol-5-yl) quinolin-4-yl) methylene) thiosemicarbazides was discovered as potent inhibitors of IKKß. In this Letter we document our early efforts at optimization of the quinoline core, the imidazole and the semithiocarbazone moiety. Most potency gains came from substitution around the 6- and 7-positions of the quinoline ring. Replacement of the semithiocarbazone with a semicarbazone decreased potency but led to some measurable exposure.


Asunto(s)
Quinasa I-kappa B/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/química , Semicarbacidas/química , Animales , Perros , Femenino , Ensayos Analíticos de Alto Rendimiento , Quinasa I-kappa B/metabolismo , Masculino , Microsomas/metabolismo , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacocinética , Quinolinas/química , Ratas , Semicarbacidas/síntesis química , Semicarbacidas/farmacocinética , Relación Estructura-Actividad
7.
Nanomaterials (Basel) ; 9(7)2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31266235

RESUMEN

Terahertz (THz) radiation has received much attention during the past few decades for its potential applications in various fields, such as spectroscopy, imaging, and wireless communications. To use terahertz waves for data transmission in different application systems, the efficient and rapid modulation of terahertz waves is required and has become an in-depth research topic. Since the turn of the century, research on metasurfaces has rapidly developed, and the scope of novel functions and operating frequency ranges has been substantially expanded, especially in the terahertz range. The combination of metasurfaces and semiconductors has facilitated both new opportunities for the development of dynamic THz functional devices and significant achievements in THz modulators. This paper provides an overview of THz modulators based on different kinds of dynamic tunable metasurfaces combined with semiconductors, two-dimensional electron gas heterostructures, superconductors, phase-transition materials, graphene, and other 2D material. Based on the overview, a brief discussion with perspectives will be presented. We hope that this review will help more researchers learn about the recent developments and challenges of THz modulators and contribute to this field.

8.
Bioorg Med Chem Lett ; 18(24): 6352-6, 2008 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-18993068

RESUMEN

A new series of pyrazolo[3,4-d]pyrimidine-3,6-diamines was designed and synthesized as potent and selective inhibitors of the nonreceptor tyrosine kinase, ACK1. These compounds arose from efforts to rigidify an earlier series of N-aryl pyrimidine-5-carboxamides. The synthesis and structure-activity relationships of this new series of inhibitors are reported. The most promising compounds were also profiled for their pharmacokinetic properties.


Asunto(s)
Diaminas/antagonistas & inhibidores , Inhibidores Enzimáticos/síntesis química , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Pirazoles/química , Pirimidinas/química , Animales , Química Farmacéutica/métodos , Cristalografía por Rayos X/métodos , Diseño de Fármacos , Inhibidores Enzimáticos/farmacología , Concentración 50 Inhibidora , Masculino , Modelos Químicos , Conformación Molecular , Proteínas Tirosina Quinasas/química , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad
9.
Medicine (Baltimore) ; 97(34): e11981, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30142832

RESUMEN

To study the relationship between pigment epithelium-derived factor (PEDF) rs1136287, rs1894286 polymorphisms and the risk of age-related macular degeneration (AMD) in northern Chinese populations.The study was carried out on case-control methods. Ninety-six patients with AMD and 98 health controls were recruited who were matched with the former by age and gender, rs1136287 and rs1894286 were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Hardy-Weinberg equilibrium (HWE) was also checked by χ test. The distribution frequencies of genotype, allele, and haplotype were calculated by direct counting method. The genotype, allele, and haplotype distribution differences between the case and control groups were analyzed by chi-square test, and odds ratio (OR) and 95% confidence interval (CI) was used to express the relative risk of AMD in northern Chinese populations. The linkage disequilibrium (LD) and haplotype analyses were conducted with Haploview software.The genotype and allele distribution frequencies in rs1136287 were obviously between in cases and controls (P < .05). TT genotype might lead to 3.24 times risk of AMD occurrence compared with CC genotype (OR = 3.24, 95% CI = 1.26-8.32), and C allele also played an increased risk role in the attack of AMD (OR = 1.58, 95% CI = 1.06-2.38). The T-C haplotype frequency of rs1136287-rs1894286 in PEDF were significantly correlated to the increased susceptibility to AMD (OR = 1.57, 95% CI = 1.02-2.40).The rs1136287 polymorphism in PEDF may be related to the occurrence risk of AMD. Additionally, a haplotype is also a non-ignorable risk factor.


Asunto(s)
Proteínas del Ojo/genética , Predisposición Genética a la Enfermedad/genética , Degeneración Macular/genética , Factores de Crecimiento Nervioso/genética , Polimorfismo de Longitud del Fragmento de Restricción/genética , Serpinas/genética , Anciano , Anciano de 80 o más Años , Pueblo Asiatico/genética , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , China , Femenino , Frecuencia de los Genes , Genotipo , Haplotipos , Humanos , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Reacción en Cadena de la Polimerasa , Factores de Riesgo
10.
Chin Med J (Engl) ; 120(9): 820-4, 2007 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-17531125

RESUMEN

BACKGROUND: Congenital cataract is a highly heterogeneous disorder at both the genetic and phenotypic levels. This study was conducted to identify disease locus for autosomal dominant congenital cataracts in a four generation Chinese family. METHODS: Family history and clinical data were recorded. All the members were genotyped with microsatellite markers which are close to the known genetic loci for autosomal congenital cataracts. Two-point Lod scores were obtained using the MLINK of the LINKAGE program package (ver 5.1). Candidate genes were amplified by polymerase chain reaction (PCR) and direct cycle sequencing. RESULTS: The maximum Lod score of Zmax-2.11 was obtained with three microsatellite markers D22S258, D22S315, and D22S1163 at recombination fraction theta=0. Haplotype analysis showed that the disease gene was localized to a 18.5 Mbp region on chromosome 22 flanked by markers D22S1174 and D22S270, spanning the beta-crystallin gene cluster. A c.752T-->C mutation in exon 6 of CRYBB1 gene, which resulted in a heterozygous S228P mutation in predicted protein, was found to cosegregate with cataract in the family. CONCLUSIONS: This study identified a novel mutation in CRYBB1 gene in a Chinese family with autosomal dominant congenital cataract. These results provide strong evidence that CRYBB1 is a pathogenic gene for congenital cataract.


Asunto(s)
Catarata/congénito , Catarata/genética , Genes Dominantes , Mutación Missense , Cadena B de beta-Cristalina/genética , Secuencia de Aminoácidos , Femenino , Ligamiento Genético , Humanos , Masculino , Datos de Secuencia Molecular
11.
Medicine (Baltimore) ; 96(47): e8190, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29381911

RESUMEN

The purpose of this study was to investigate the correlation of single nucleotide polymorphisms (SNPs) in Matrix metalloproteinase -2 (MMP-2) gene and the risk of age-related macular degeneration (AMD) in Chinese Han population.A total of 126 AMD patients and 141 healthy controls participated in this study. Genotypes of MMP-2 gene polymorphisms were identified by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). χtest was used to detect the differences of genotypes and alleles frequencies between case and control groups. Relative risk of AMD was evaluated by odds ratios (ORs) with 95% confidence intervals (CIs).Distribution of variant allele carriers (computed tomography + TT genotypes) of MMP-2 gene rs243865 SNP was significantly different between case and control groups, and might act as protective factors for the onset of AMD (P = .044, OR = 0.583, 95% CI = 0.344-0.987). Nevertheless, the T allele might reduce the AMD risk (P = .030, OR = 0.611, 95% CI = 0.390-0.956). However, no significant association existed between rs243865 and AMD risk in the subgroup analysis based on age. GA + AA genotypes of rs243866 SNP may associate with a decreased risk of AMD in the age≤65 years subgroup (P = .028, OR = 0.399, 95% CI = 0.174-0.915).MMP-2 gene rs243865 and rs243866 SNPs associated with the risk of AMD. Further studies should be performed to confirm the results.


Asunto(s)
Degeneración Macular/epidemiología , Metaloproteinasa 2 de la Matriz/genética , Factores de Edad , Anciano , Pueblo Asiatico/genética , Estudios de Casos y Controles , China/epidemiología , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Degeneración Macular/genética , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo de Nucleótido Simple
12.
J Med Chem ; 59(15): 7252-67, 2016 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-27411843

RESUMEN

Optimization of the potency and pharmacokinetic profile of 2,3,4-trisubstituted quinoline, 4, led to the discovery of two potent, selective, and orally bioavailable PI3Kδ inhibitors, 6a (AM-0687) and 7 (AM-1430). On the basis of their improved profile, these analogs were selected for in vivo pharmacodynamic (PD) and efficacy experiments in animal models of inflammation. The in vivo PD studies, which were carried out in a mouse pAKT inhibition animal model, confirmed the observed potency of 6a and 7 in biochemical and cellular assays. Efficacy experiments in a keyhole limpet hemocyanin model in rats demonstrated that administration of either 6a or 7 resulted in a strong dose-dependent reduction of IgG and IgM specific antibodies. The excellent in vitro and in vivo profiles of these analogs make them suitable for further development.


Asunto(s)
Descubrimiento de Drogas , Inhibidores de las Quinasa Fosfoinosítidos-3 , Inhibidores de Proteínas Quinasas/farmacología , Piridinas/farmacología , Quinolinas/farmacología , Animales , Linfocitos B/efectos de los fármacos , Linfocitos B/inmunología , Fosfatidilinositol 3-Quinasa Clase Ia/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Ratones , Modelos Moleculares , Estructura Molecular , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Piridinas/síntesis química , Piridinas/química , Quinolinas/síntesis química , Quinolinas/química , Relación Estructura-Actividad
13.
J Med Chem ; 58(1): 480-511, 2015 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-25469863

RESUMEN

The development and optimization of a series of quinolinylpurines as potent and selective PI3Kδ kinase inhibitors with excellent physicochemical properties are described. This medicinal chemistry effort led to the identification of 1 (AMG319), a compound with an IC50 of 16 nM in a human whole blood assay (HWB), excellent selectivity over a large panel of protein kinases, and a high level of in vivo efficacy as measured by two rodent disease models of inflammation.


Asunto(s)
Adenosina/farmacología , Enfermedades Autoinmunes/prevención & control , Fosfatidilinositol 3-Quinasa Clase I/antagonistas & inhibidores , Inflamación/prevención & control , Inhibidores de Proteínas Quinasas/farmacología , Quinolinas/farmacología , Adenosina/química , Adenosina/metabolismo , Animales , Células Cultivadas , Fosfatidilinositol 3-Quinasa Clase I/química , Fosfatidilinositol 3-Quinasa Clase I/metabolismo , Cristalografía por Rayos X , Modelos Animales de Enfermedad , Descubrimiento de Drogas , Femenino , Humanos , Ratones Endogámicos BALB C , Ratones Transgénicos , Modelos Químicos , Modelos Moleculares , Estructura Molecular , Unión Proteica , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/metabolismo , Estructura Terciaria de Proteína , Quinolinas/química , Quinolinas/metabolismo , Ratas Endogámicas Lew , Células Sf9 , Relación Estructura-Actividad
14.
J Med Chem ; 57(8): 3464-83, 2014 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-24670009

RESUMEN

The discovery and optimization of a series of acyl CoA:diacylglycerol acyltransferase 1 (DGAT1) inhibitors based on a pyrimido[4,5-b][1,4]oxazine scaffold is described. The SAR of a moderately potent HTS hit was investigated resulting in the discovery of phenylcyclohexylacetic acid 1, which displayed good DGAT1 inhibitory activity, selectivity, and PK properties. During preclinical toxicity studies a metabolite of 1 was observed that was responsible for elevating the levels of liver enzymes ALT and AST. Subsequently, analogues were synthesized to preclude the formation of the toxic metabolite. This effort resulted in the discovery of spiroindane 42, which displayed significantly improved DGAT1 inhibition compared to 1. Spiroindane 42 was well tolerated in rodents in vivo, demonstrated efficacy in an oral triglyceride uptake study in mice, and had an acceptable safety profile in preclinical toxicity studies.


Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Inhibidores Enzimáticos/síntesis química , Oxazinas/síntesis química , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Perros , Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacología , Ensayos Analíticos de Alto Rendimiento , Macaca mulatta , Ratones , Ratones Endogámicos C57BL , Oxazinas/farmacología , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad , Triglicéridos/metabolismo
15.
ACS Med Chem Lett ; 4(8): 790-4, 2013 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-24900747

RESUMEN

GPR142 is a G protein-coupled receptor that is predominantly expressed in pancreatic ß-cells. GPR142 agonists stimulate insulin secretion in the presence of high glucose concentration, so that they could be novel insulin secretagogues with reduced or no risk of hypoglycemia. We report here the optimization of HTS hit compound 1 toward a proof of concept compound 33, which showed potent glucose lowering effects during an oral glucose tolerance test in mice and monkeys.

16.
PLoS One ; 7(11): e49785, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23189163

RESUMEN

Because of technological limitations, the primer and amplification biases in targeted sequencing of 16S rRNA genes have veiled the true microbial diversity underlying environmental samples. However, the protocol of metagenomic shotgun sequencing provides 16S rRNA gene fragment data with natural immunity against the biases raised during priming and thus the potential of uncovering the true structure of microbial community by giving more accurate predictions of operational taxonomic units (OTUs). Nonetheless, the lack of statistically rigorous comparison between 16S rRNA gene fragments and other data types makes it difficult to interpret previously reported results using 16S rRNA gene fragments. Therefore, in the present work, we established a standard analysis pipeline that would help confirm if the differences in the data are true or are just due to potential technical bias. This pipeline is built by using simulated data to find optimal mapping and OTU prediction methods. The comparison between simulated datasets revealed a relationship between 16S rRNA gene fragments and full-length 16S rRNA sequences that a 16S rRNA gene fragment having a length >150 bp provides the same accuracy as a full-length 16S rRNA sequence using our proposed pipeline, which could serve as a good starting point for experimental design and making the comparison between 16S rRNA gene fragment-based and targeted 16S rRNA sequencing-based surveys possible.


Asunto(s)
Bacterias/genética , Biología Computacional/métodos , Metagenómica , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Algoritmos , Simulación por Computador , Bases de Datos de Ácidos Nucleicos , Internet , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
17.
J Med Chem ; 55(17): 7667-85, 2012 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-22876881

RESUMEN

Structure-based rational design led to the synthesis of a novel series of potent PI3K inhibitors. The optimized pyrrolopyridine analogue 63 was a potent and selective PI3Kß/δ dual inhibitor that displayed suitable physicochemical properties and pharmacokinetic profile for animal studies. Analogue 63 was found to be efficacious in animal models of inflammation including a keyhole limpet hemocyanin (KLH) study and a collagen-induced arthritis (CIA) disease model of rheumatoid arthritis. These studies highlight the potential therapeutic value of inhibiting both the PI3Kß and δ isoforms in the treatment of a number of inflammatory diseases.


Asunto(s)
Descubrimiento de Drogas , Evaluación Preclínica de Medicamentos , Inhibidores de las Quinasa Fosfoinosítidos-3 , Inhibidores de Proteínas Quinasas/farmacología , Modelos Moleculares
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