Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Mol Psychiatry ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724566

RESUMEN

Psychiatric disorders are highly heritable yet polygenic, potentially involving hundreds of risk genes. Genome-wide association studies have identified hundreds of genomic susceptibility loci with susceptibility to psychiatric disorders; however, the contribution of these loci to the underlying psychopathology and etiology remains elusive. Here we generated deep human brain proteomics data by quantifying 11,608 proteins across 268 subjects using 11-plex tandem mass tag coupled with two-dimensional liquid chromatography-tandem mass spectrometry. Our analysis revealed 788 cis-acting protein quantitative trait loci associated with the expression of 883 proteins at a genome-wide false discovery rate <5%. In contrast to expression at the transcript level and complex diseases that are found to be mainly influenced by noncoding variants, we found protein expression level tends to be regulated by non-synonymous variants. We also provided evidence of 76 shared regulatory signals between gene expression and protein abundance. Mediation analysis revealed that for most (88%) of the colocalized genes, the expression levels of their corresponding proteins are regulated by cis-pQTLs via gene transcription. Using summary data-based Mendelian randomization analysis, we identified 4 proteins and 19 genes that are causally associated with schizophrenia. We further integrated multiple omics data with network analysis to prioritize candidate genes for schizophrenia risk loci. Collectively, our findings underscore the potential of proteome-wide linkage analysis in gaining mechanistic insights into the pathogenesis of psychiatric disorders.

2.
Chemistry ; 30(3): e202303133, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-37823679

RESUMEN

Homocubane, a highly strained cage hydrocarbon, contains two very different positions for the introduction of a nitrogen atom into the skeleton, e. g., a position 1 exchange results in a tertiary amine whereas position 9 yields a secondary amine. Herein reported is the synthesis of 9-azahomocubane along with associated structural characterization, physical property analysis and chemical reactivity. Not only is 9-azahomocubane readily synthesized, and found to be stable as predicted, the basicity of the secondary amine was observed to be significantly lower than the structurally related azabicyclo[2.2.1]heptane, although similar to 1-azahomocubane.

3.
J Org Chem ; 89(1): 798-803, 2024 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-38131648

RESUMEN

The unusual and sterically constrained amino acid, seco-1-azacubane-2-carboxylic acid, was incorporated into a range of bioactive chemical templates, including enalaprilat, perindoprilat, endomorphin-2 and isoniazid, and subjected to biological testing. The endomorphin-2 derivative displayed increased activity at the δ opioid receptor, but a loss in activity was observed in the other cases, although human normal cell line evaluation suggests limited cytotoxic effects.


Asunto(s)
Ácidos Carboxílicos , Receptores Opioides mu , Humanos , Receptores Opioides mu/química , Receptores Opioides mu/metabolismo , Aminoácidos , Línea Celular
4.
Environ Res ; 252(Pt 2): 118895, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38604483

RESUMEN

Landfill gases can have numerous detrimental effects on the global climate and urban ecological environment. The protective efficacy of the final cover layer against landfill gases, following exposure to periodic natural meteorological changes during long-term service, remains unclear. This study conducted centrifuge tests and gas permeability tests on compacted loess. The experiments examined the impact and relationship of wetting-drying cycles and dry density on the soil water characteristic curve (SWCC) and gas permeability of compacted loess. Research findings reveal that during the dehumidification process of compacted loess, the gas permeability increases non-linearly, varying the gas permeability of soil with different densities to different extents under wetting-drying cycles. Two models were introduced to describe the impact of wetting-drying cycles on gas permeability of loess with various dry densities, where fitting parameters increased with the number of wetting-drying cycles. Sensitivity analysis of the parameters in the Parker-Van Genuchten-Mualem (P-VG-M) model suggests that parameter γ's accuracy should be ensured in practical applications. Finally, from a microstructural perspective, wetting-drying cycles cause dispersed clay and other binding materials coalesce to fill minuscule pores, leading to an increase in the effective pores responsible for the gas permeability of the soil. These research results offer valuable guidance for designing water retention and gas permeability in compacted loess cover layers under wetting-drying cycles.


Asunto(s)
Permeabilidad , Suelo , Suelo/química , Agua/química , Humectabilidad , Eliminación de Residuos/métodos , Gases , Desecación/métodos , Contaminantes Atmosféricos/análisis
5.
Anal Chem ; 95(5): 2645-2652, 2023 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-36693249

RESUMEN

Aptamers incorporating chemically modified bases can achieve superior affinity and specificity compared to natural aptamers, but their characterization remains a labor-intensive, low-throughput task. Here, we describe the "non-natural aptamer array" (N2A2) system, in which a minimally modified Illumina MiSeq instrument is used for the high-throughput generation and characterization of large libraries of base-modified DNA aptamer candidates based on both target binding and specificity. We first demonstrate the capability to screen multiple different base modifications to identify the optimal chemistry for high-affinity target binding. We next use N2A2 to generate aptamers that can maintain excellent specificity even in complex samples, with equally strong target affinity in both buffer and diluted human serum. For both aptamers, affinity was formally calculated with gold-standard binding assays. Given that N2A2 requires only minor mechanical modifications to the MiSeq, we believe that N2A2 offers a broadly accessible tool for generating high-quality affinity reagents for diverse applications.


Asunto(s)
Aptámeros de Nucleótidos , Humanos , Aptámeros de Nucleótidos/química , Bioensayo , Técnica SELEX de Producción de Aptámeros
6.
Theor Appl Genet ; 136(1): 3, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36651948

RESUMEN

KEY MESSAGE: The QYm.nau-2D locus conferring wheat yellow mosaic virus resistance is an exotic introgression and we developed 11 diagnostic markers tightly linked to QYm.nau-2D. Wheat yellow mosaic virus (WYMV) is a serious disease of winter wheat in China. Breeding resistant varieties is the most effective strategy for WYMV control. A WYMV resistant locus QYm.nau-2D on the chromosome arm 2DL has been repeatedly reported but the mapped region is large. In the present study, we screened recombinants using a biparental population and mapped QYm.nau-2D into an 18.8 Mb physical interval. By genome-wide association studies of 372 wheat varieties for WYMV resistance in four environments, we narrowed down QYm.nau-2D into a 16.4 Mb interval. Haplotype analysis indicated QYm.nau-2D were present as six different states due to recombination during hybridization breeding. QYm.nau-2D was finally mapped into a linkage block of 11.2 Mb. Chromosome painting using 2D specific probes and collinearity analysis among the published sequences corresponding to QYm.nau-2D region indicated the block was an exotic introgression. The Illumina-sequenced reads of four diploid Aegilops species were mapped to the sequence of Fielder, a variety having the introgression. The mapping reads were significantly increased at the putative introgression regions of Fielder. Ae. uniaristata (NN) had the highest mapping reads, suggesting that QYm.nau-2D was possibly an introgression from genome N. We investigated the agronomic performances of different haplotypes and observed no linkage drag of the alien introgression for the 15 tested traits. For marker-assisted selection of QYm.nau-2D, we developed 11 diagnostic markers tightly linked to the locus. This research provided a case study of an exotic introgression, which has been utilized in wheat improvement for WYMV resistance.


Asunto(s)
Virus del Mosaico , Potyviridae , Triticum/genética , Mapeo Cromosómico , Marcadores Genéticos , Resistencia a la Enfermedad/genética , Estudio de Asociación del Genoma Completo , Enfermedades de las Plantas/genética , Fitomejoramiento
7.
J Org Chem ; 88(18): 12867-12871, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37647582

RESUMEN

seco-1-Azacubane-2-carboxylic acid, an unusual and sterically constrained amino acid, was found to undergo amide bond formation at both the N- and C-termini using proline based bioactive molecule templates as a concept platform.

8.
Proteomics ; 22(22): e2200120, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35856475

RESUMEN

Protein kinases are a crucial component of signaling pathways involved in a wide range of cellular responses, including growth, proliferation, differentiation, and migration. Systematic investigation of protein kinases is critical to better understand phosphorylation-mediated signaling pathways and may provide insights into the development of potential therapeutic drug targets. Here we perform a systems-level analysis of the mouse kinome by analyzing multi-omics data. We used bulk and single-cell transcriptomic data from the C57BL/6J mouse strain to define tissue- and cell-type-specific expression of protein kinases, followed by investigating variations in sequence and expression between C57BL/6J and DBA/2J strains. We then profiled a deep brain phosphoproteome from C57BL/6J and DBA/2J strains as well as their reciprocal hybrids to infer the activity of the mouse kinome. Finally, we performed phenome-wide association analysis using the BXD recombinant inbred (RI) mice (a cross between C57BL/6J and DBA/2J strains) to identify any associations between variants in protein kinases and phenotypes. Collectively, our study provides a comprehensive analysis of the mouse kinome by investigating genetic sequence variation, tissue-specific expression patterns, and associations with downstream phenotypes.


Asunto(s)
Proteínas Quinasas , Ratones , Animales , Ratones Endogámicos DBA , Ratones Endogámicos C57BL , Fenotipo , Proteínas Quinasas/genética , Especificidad de la Especie
9.
Respir Res ; 23(1): 38, 2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35189885

RESUMEN

BACKGROUND: Studies on the associations between ambient temperature and asthma hospitalizations are limited, and the results are controversial. We aimed to assess the short-term effects of ambient temperature on the risk of asthma hospitalizations and quantify the hospitalization burdens of asthma attributable to non-optimal temperature in adults in Beijing, China. METHODS: We collected daily asthma hospitalizations, meteorological factors and air quality data in Beijing from 2012 to 2015. We applied a time-stratified case-crossover design and fitted a distributed lag non-linear model with a conditional quasi-Poisson regression to explore the association between ambient temperature and adult asthma hospitalizations. The effect modifications of these associations by gender and age were assessed by stratified analyses. We also computed the attributable fractions and numbers with 95% empirical confidence intervals (eCI) of asthma hospitalizations due to extreme and moderate temperatures. RESULTS: From 2012 to 2015, we identified a total of 18,500 hospitalizations for asthma among adult residents in Beijing, China. Compared with the optimal temperature (22 °C), the cumulative relative risk (CRR) over lag 0-30 days was 2.32 with a 95% confidence interval (CI) of 1.57-3.42 for extreme cold corresponding to the 2.5th percentile (- 6.5 °C) of temperature distribution and 2.04 (95% CI 1.52-2.74) for extreme heat corresponding to the 97.5th percentile (29 °C) of temperature distribution. 29.1% (95% eCI 17.5-38.0%) of adult asthma hospitalizations was attributable to non-optimum temperatures. Moderate cold temperatures yielded most of the burdens, with an attributable fraction of 20.3% (95% eCI 9.1-28.7%). The temperature-related risks of asthma hospitalizations were more prominent in females and younger people (19-64 years old). CONCLUSIONS: There was a U-shaped association between ambient temperature and the risk of adult asthma hospitalizations in Beijing, China. Females and younger patients were more vulnerable to the effects of non-optimum temperatures. Most of the burden was attributable to moderate cold. Our findings may uncover the potential impact of climate changes on asthma exacerbations.


Asunto(s)
Asma/terapia , Hospitalización/estadística & datos numéricos , Medición de Riesgo/métodos , Temperatura , Adulto , Asma/epidemiología , Beijing/epidemiología , Estudios Cruzados , Estudios Transversales , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
10.
Bioorg Med Chem ; 69: 116889, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35779512

RESUMEN

Multiple sclerosis-associated central neuropathic pain (MS-CNP) is difficult to alleviate with clinically used pain-killers and so there is a large unmet medical need for novel treatments for alleviating MS-CNP. Although (R)-alpha lipoic acid (ALA) evoked significant pain relief efficacy in a mouse model of multiple sclerosis-associated central neuropathic pain (MS-CNP), this dietary supplement has poor oral bioavailability due to low gastric stability. Eight ester prodrugs of the R enantiomer of ALA [(R)-ALA] were designed encompassing a range of biocompatible hydrophobic and hydrophilic features and synthesized in an effort to identify a prodrug candidate that was stable at gastric and upper gastrointestinal tract (GIT) pH, and that could be released (hydrolyzed by esterases) in the blood to (R)-ALA immediately after absorption into the portal vein (i.e., highly desirable features for pain relief development). These biocompatible hydrophobic and hydrophilic (R)-ALA pro-dugs underwent comprehensive preliminary screening to reveal PD-ALA4 HCl salt (10) as a promising candidate and PD-ALA 7 (8) could be a viable substitute, utilizing enzyme-free gastric and intestinal stability assessments, LogP evaluations, in vitro plasma stability and caco-2 cell monolayer permeability.


Asunto(s)
Esclerosis Múltiple , Neuralgia , Profármacos , Ácido Tióctico , Animales , Disponibilidad Biológica , Células CACO-2 , Humanos , Ratones , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/tratamiento farmacológico , Neuralgia/tratamiento farmacológico , Profármacos/química , Profármacos/farmacología , Profármacos/uso terapéutico , Ácido Tióctico/farmacología , Ácido Tióctico/uso terapéutico
11.
BMC Public Health ; 22(1): 996, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35581565

RESUMEN

BACKGROUND: The rapid development of digital health has reduced the time and cost of medical treatment, bringing efficient and economical benefits. However, older adults all over the world are deficient in digital health knowledge and skills to varying degrees. This study intends to investigate the current status and influencing factors of digital health literacy among community-dwelling older adults in Southwest China, so as to provide theoretical reference for global digital health researches and the construction of gerontological digital health service models. METHODS: A cross-sectional survey was conducted from September 2020 to April 2021 in Chongqing, China. 572 community-dwelling older adults (≥ 65 years) were surveyed by stratified sampling. Data on sociodemographic characteristics, Internet usage, attitude towards Internet health information and digital health literacy were collected. Wherein, the digital health literacy assessment adopted the Digital Health Literacy Assessment Scale for community-dwelling older adults, which was developed by the research group, proven to be with good internal consistency (0.941), split-half reliability (0.889), test-retest reliability (0.941), content validity (0.967), criterion validity (0.938) and construct validity. The influencing factors were explored by univariate analysis and multiple linear regression analysis. RESULTS: The average score of digital health literacy was 37.10 (SD 18.65). Univariate analysis showed that there were statistically significant differences in the comparison of digital health literacy according to 16 variables, such as different age and education levels. Multiple linear regression analysis showed that education level, marital status, self-rated health status, degree of health concerns, duration of Internet usage, time spent using the Internet per day, frequency of Internet usage, frequency of receiving guidance passively from family members, perceived usefulness, perceived ease of use and perceived reliability were positively correlated with digital health literacy, while age and perceived risk were negatively correlated with digital health literacy. CONCLUSION: The overall digital health literacy of community-dwelling older adults in Southwest China is relatively low. In the future, health professionals should fully consider the diverse influencing factors of digital health literacy, assess individual differences and provide targeted intervention programs. Meanwhile, global public health authorities should integrate health resources effectively, and seek health service models for older adults in line with the development of the digital age to narrow the digital divide.


Asunto(s)
Alfabetización en Salud , Telemedicina , Anciano , China , Estudios Transversales , Humanos , Vida Independiente , Internet , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
12.
BMC Geriatr ; 21(1): 450, 2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34344309

RESUMEN

BACKGROUND: With the development of digital media, online activities are increasingly becoming part of the daily life of older adults. Widowed older adults generally would face changes in social interactions and activities due to widowhood; thus, the importance of online participation may be more prominent in this population. However, a detailed evidence on the experiences of online social participation among widowed older adults is relatively sparse. This study aimed to explore widowed older adults' perceptions regarding online social participation in southwestern China. METHODS: This study adopted a qualitative approach. Semi-structured, in-depth individual interviews were conducted with 19 widowed older adults between September-December 2020. Thematic analysis was applied to analyse the data. RESULTS: Two major themes, "benefits" and "barriers" were identified from the original data analysis. Subcategories concerning the theme "benefits" were "benefit perception (convenience, flexible time, supplementation)", "health promotion", "emotional comfort", and "social connection". Subcategories of "barriers" were "worries: personal economic loss", "concerns: security of digital device", "troubles: the diversity of online social participation", and "difficulties: using digital media". CONCLUSIONS: Social participation of widowed older adults in southwestern China has begun to be integrated into the digital world; however, it remains at an early stage with the simple purpose of engagement. The older adults may face many challenges for online social participation. Although there are barriers and challenges in online social participation, widowed older adults can reap its benefits, which can be used as an important measure to facilitate a fulfilling life and successful ageing. There is no doubt that online social participation will become a trend within the foreseeable future. Family, friends and health care professionals should pay more attention to the needs of online social participation in widowed older adults and provide adequate support for them to achieve a meaningful life.


Asunto(s)
Participación Social , Viudez , Anciano , China , Femenino , Humanos , Internet , Investigación Cualitativa
13.
Toxicol Appl Pharmacol ; 357: 70-79, 2018 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-30130555

RESUMEN

Both epidemiological investigations and animal studies have linked arsenic-contaminated water to cancers, including skin, liver and lung cancers. Besides genotoxicity, arsenic exposure-related pathogenesis of disease is widely considered through epigenetic mechanisms; however, the underlying mechanism remains to be determined. Herein we explore the initial epigenetic changes via acute sodium arsenite (As) exposures of mouse embryonic fibroblast (MEF) cells and histone H3K79 methyltransferase Dot1L knockout (Dot1L-/-) MEF cells. Our RNA-seq and Western blot data demonstrated that, in both cell lines, acute As exposure abolished histone acetyltransferase p300 at the RNA level and subsequent protein level. Consequently, p300-specific main target histone H3K27ac, a marker separating active from poised enhancers, decreased dramatically as validated by both Western blot and ChIP-qPCR/seq analyses. Concomitantly, H3K4me1 as another well-known marker for enhancers also showed significant decreases, suggesting an underappreciated crosstalk between H3K4me1 and H3K27ac involved in As exposure. Significantly, As exposure-reduced H3K27ac and H3K4me1 inhibited the expression of genes including EP300 itself and Kruppel Like Factor 4(Klf4) that both are tumor suppressor genes. Collectively, our investigations identified p300 as an internal bridging factor within cells to sense external environmental As exposure to alter chromatin, thereby changing gene transcription for disease pathogenesis.


Asunto(s)
Arsenitos/toxicidad , Fibroblastos/efectos de los fármacos , Histonas/metabolismo , Compuestos de Sodio/toxicidad , Factores de Transcripción p300-CBP/antagonistas & inhibidores , Animales , Línea Celular , Regulación de la Expresión Génica/efectos de los fármacos , Factor 4 Similar a Kruppel , Ratones , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Transcripción p300-CBP/metabolismo
14.
Neuroepidemiology ; 50(1-2): 63-73, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29421788

RESUMEN

BACKGROUND: The study aimed to analyze the hospital charges of the inpatients with acute ischemic stroke in Beijing and determine the factors associated with hospital costs. METHODS: Medical records of hospitalized patients with a primary diagnosis of ischemic stroke according to International Classification of Diseases 10th Revision codes were collected from 121 hospitals in Beijing from March 1, 2012, to February 28, 2015. Distribution characteristics of hospital charges for different hospital levels (level 2 hospitals and level 3 hospitals) and types (Western medicine hospitals and Chinese medicine hospitals) were studied. Linear regression analysis was used to examine the association among hospital costs and factors that influenced total hospital charges. RESULTS: There were 158,781 admissions for ischemic stroke, 63.1% of the patients were male and their mean age was 67.7 ± 12.4 years, the median length of hospital stay (LOHS) was 13.5 days (interquartile range 9.9-18.1 days). The median hospital charge was 2,112 (1,436-3,147) US dollars. Of these, 46.7% were for medicine, 21.1% for laboratory and examination, and 16.3% for therapy. LOHS, hospital level, and pulmonary infection were key determinants of the hospital charges. CONCLUSIONS: The proportion of medicine fees for the ischemic stroke inpatients showed a downward trend during the period from 2012 to 2015, but medicine fees still accounted for the largest percentage of hospital charges in China. LOHS emerged to be the main determinant of the cost. Decreasing medicine fees and LOHS might be strategies to decrease hospital charges and reduce economic burden of stroke in China.


Asunto(s)
Isquemia Encefálica/economía , Costos de la Atención en Salud , Precios de Hospital , Hospitalización/economía , Pacientes Internos , Accidente Cerebrovascular/economía , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/terapia , China , Femenino , Humanos , Tiempo de Internación/economía , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/terapia
15.
Pacing Clin Electrophysiol ; 41(11): 1441-1446, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30225893

RESUMEN

BACKGROUND: Atrial fibrillation (AF) is an important arrhythmia associated with cardiovascular morbidity and mortality. This study is focused on exploring the potential relationship between short-term air pollution exposure and occurrence of AF. METHODS: A case-crossover design was used to investigate the effect of pollutants on AF occurrence among 100 patients from 2013 to 2014. The air pollutants included ambient particulate matter less than 2.5 µm in aerodynamic diameter (PM2.5 ), particulate matter less than 10 µm in aerodynamic diameter (PM10 ), nitrogen dioxide (NO2 ), sulfur dioxide (SO2 ), carbon monoxide (CO), and ozone (O3 ). Participants with cardiac implantable electronic devices implanted were followed-up to December 31, 2014. RESULTS: A 10 µg/m3 increase of PM2.5 and PM10 was associated with 3.8% (95% confidence interval [CI]: 1.4-6.2) and 2.7% (95% CI: 0.6-4.8) increase in the risk of AF occurrence, respectively. No statistically significant association was noted with SO2 , NO2 , CO, and O3 . CONCLUSIONS: Short-term exposure to particular matter, both PM2.5 and PM10 , is associated with an increased risk of AF. This further demonstrates the urgency for air quality monitoring and control in geographical area with intense pollution.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Fibrilación Atrial/etiología , Anciano , Fibrilación Atrial/terapia , China , Estudios Cruzados , Desfibriladores Implantables , Electrocardiografía , Femenino , Humanos , Masculino , Marcapaso Artificial , Material Particulado , Factores de Riesgo
16.
J Am Chem Soc ; 139(40): 13977-13980, 2017 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-28938065

RESUMEN

We describe the application of T4 DNA ligase-catalyzed DNA templated oligonucleotide polymerization toward the evolution of a diversely functionalized nucleic acid aptamer for human α-thrombin. Using a 256-membered ANNNN comonomer library comprising 16 sublibraries modified with different functional groups, a highly functionalized aptamer for thrombin was raised with a dissociation constant of 1.6 nM. The aptamer was found to be selective for thrombin and required the modifications for binding affinity. This study demonstrates the most differentially functionalized nucleic acid aptamer discovered by in vitro selection and should enable the future exploration of functional group dependence during the evolution of nucleic acid polymer activity.


Asunto(s)
Aptámeros de Nucleótidos/química , Técnica SELEX de Producción de Aptámeros/métodos , Trombina/análisis , Aptámeros de Nucleótidos/metabolismo , Secuencia de Bases , ADN Ligasas/metabolismo , Biblioteca de Genes , Humanos , Trombina/metabolismo
17.
Angew Chem Int Ed Engl ; 55(42): 13164-13168, 2016 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-27633832

RESUMEN

The development and in-depth analysis of T4 DNA ligase-catalyzed DNA templated oligonucleotide polymerization toward the generation of diversely functionalized nucleic acid polymers is described. The NNNNT codon set enables low codon bias, high fidelity, and high efficiency for the polymerization of ANNNN libraries comprising various functional groups. The robustness of the method was highlighted in the copolymerization of a 256-membered ANNNN library comprising 16 sub-libraries modified with different functional groups. This enabled the generation of diversely functionalized synthetic nucleic acid polymer libraries with 93.8 % fidelity. This process should find ready application in DNA nanotechnology, DNA computing, and in vitro evolution of functional nucleic acid polymers.


Asunto(s)
ADN Ligasas/metabolismo , ADN/biosíntesis , Polímeros/metabolismo , ADN/química , Polímeros/química
18.
Biochim Biophys Acta ; 1833(12): 3346-3354, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24140207

RESUMEN

BAG3 plays a regulatory role in a number of cellular processes, including cell proliferation, apoptosis, adhesion and migration, epithelial-mesenchymal transition (EMT), autophagy activation, and virus infection. The AP-1 transcription factors are implicated in a variety of important biological processes including cell differentiation, proliferation, apoptosis and oncogenesis. Recently, it has been reported that AP-1 protein c-Jun inhibits autophagy and enhances apoptotic cell death mediated by starvation. However, the molecular mechanisms remain unclear. For the first time, the current study demonstrated that serum starvation downregulated BAG3 at the transcriptional level via c-Jun. In addition, the current study reported that BAG3 stabilized JunD mRNA, which was, at least in part, responsible for the promotion of serum starvation mediated-growth inhibition by BAG3.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Proto-Oncogénicas c-jun/metabolismo , Regulación hacia Arriba/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Reguladoras de la Apoptosis , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Medio de Cultivo Libre de Suero/farmacología , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Humanos , Estabilidad Proteica/efectos de los fármacos , Estabilidad del ARN/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transcripción Genética/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos
19.
Biochim Biophys Acta ; 1833(12): 3245-3253, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24080088

RESUMEN

Bcl-2 associated athanogene 3 (BAG3) has a modular structure that contains a BAG domain, a WW domain, a proline-rich (PxxP) domain to mediate potential interactions with chaperons and other proteins that participate in more than one signal transduction. In search for novel interacting partners, the current study identified that 78kDa glucose-regulated protein (GRP78) was a novel partner interacting with BAG3. Interaction between GRP78 and BAG3 was confirmed by coimmunoprecipitation and glutathione S-transferase (GST) pulldown. We also identified that the ATPase domain of GRP78 and BAG domain of BAG3 mediated their interaction. Counterintuitive for a prosurvival protein, BAG3 was found to promote the cytotoxicity of breast cancer MCF7, thyroid cancer FRO and glioma U87 cells subjected to genotoxic stress. In addition, the current study demonstrated that BAG3 interfered with the formation of the antiapoptotic GRP78-procaspase-7 complex, which resulted in an increased genotoxic stress-induced cytotoxicity in cancer cells. Furthermore, overexpression of GRP78 significantly blocked the enhancing effects of BAG3 on activation of caspase-7 and induction of apoptosis by genotoxic stress. Overall, these results suggested that through direct interaction BAG3 could prevent the antiapoptotic effect of GRP78 upon genotoxic stress.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Daño del ADN , Proteínas de Choque Térmico/metabolismo , Mutágenos/toxicidad , Proteínas Adaptadoras Transductoras de Señales/química , Proteínas Reguladoras de la Apoptosis , Unión Competitiva/efectos de los fármacos , Caspasa 7/metabolismo , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Doxorrubicina/farmacología , Chaperón BiP del Retículo Endoplásmico , Etopósido/farmacología , Proteínas de Choque Térmico/química , Humanos , Unión Proteica/efectos de los fármacos , Estructura Terciaria de Proteína
20.
ACS Sens ; 9(3): 1168-1177, 2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38407035

RESUMEN

The development of receptors suitable for the continuous detection of analytes in complex, interferent-rich samples remains challenging. Antibodies are highly sensitive but difficult to engineer in order to introduce signaling functionality, while aptamer switches are easy to construct but often yield only a modest target sensitivity. We present here a programmable antibody and DNA aptamer switch (PANDAS), which combines the desirable properties of both receptors by using a nucleic acid tether to link an analyte-specific antibody to an internal strand-displacement (ISD)-based aptamer switch that recognizes the same target through different epitopes. The antibody increases PANDAS analyte binding due to its high affinity, and the effective concentration between the two receptors further enhances two-epitope binding and fluorescent aptamer signaling. We developed a PANDAS sensor for the clotting protein thrombin and show that a tuned design achieves a greater than 300-fold enhanced sensitivity compared to that of using an aptamer alone. This design also exhibits reversible binding, enabling repeated measurements with a temporal resolution of ∼10 min, and retains excellent sensitivity even in interferent-rich samples. With future development, this PANDAS approach could enable the adaptation of existing protein-binding aptamers with modest affinity to sensors that deliver excellent sensitivity and minute-scale resolution in minimally prepared biological specimens.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Ácidos Nucleicos , Aptámeros de Nucleótidos/química , Anticuerpos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA