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1.
Cell ; 175(2): 347-359.e14, 2018 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-30290141

RESUMEN

We analyze whole-genome sequencing data from 141,431 Chinese women generated for non-invasive prenatal testing (NIPT). We use these data to characterize the population genetic structure and to investigate genetic associations with maternal and infectious traits. We show that the present day distribution of alleles is a function of both ancient migration and very recent population movements. We reveal novel phenotype-genotype associations, including several replicated associations with height and BMI, an association between maternal age and EMB, and between twin pregnancy and NRG1. Finally, we identify a unique pattern of circulating viral DNA in plasma with high prevalence of hepatitis B and other clinically relevant maternal infections. A GWAS for viral infections identifies an exceptionally strong association between integrated herpesvirus 6 and MOV10L1, which affects piwi-interacting RNA (piRNA) processing and PIWI protein function. These findings demonstrate the great value and potential of accumulating NIPT data for worldwide medical and genetic analyses.


Asunto(s)
Pueblo Asiatico/genética , Diagnóstico Prenatal/métodos , Adulto , Alelos , China , ADN/genética , Etnicidad/genética , Femenino , Frecuencia de los Genes/genética , Pruebas Genéticas , Variación Genética/genética , Genética de Población/métodos , Estudio de Asociación del Genoma Completo/métodos , Genómica/métodos , Migración Humana , Humanos , Embarazo , Análisis de Secuencia de ADN
2.
Nat Chem Biol ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38744986

RESUMEN

G-protein-coupled receptors (GPCRs) are key regulators of human physiology and are the targets of many small-molecule research compounds and therapeutic drugs. While most of these ligands bind to their target GPCR with high affinity, selectivity is often limited at the receptor, tissue and cellular levels. Antibodies have the potential to address these limitations but their properties as GPCR ligands remain poorly characterized. Here, using protein engineering, pharmacological assays and structural studies, we develop maternally selective heavy-chain-only antibody ('nanobody') antagonists against the angiotensin II type I receptor and uncover the unusual molecular basis of their receptor antagonism. We further show that our nanobodies can simultaneously bind to angiotensin II type I receptor with specific small-molecule antagonists and demonstrate that ligand selectivity can be readily tuned. Our work illustrates that antibody fragments can exhibit rich and evolvable pharmacology, attesting to their potential as next-generation GPCR modulators.

3.
Genome Res ; 31(7): 1150-1158, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34155038

RESUMEN

Protein-truncating variants (PTVs) have important impacts on phenotype diversity and disease. However, their population genetics characteristics in more globally diverse populations are not well defined. Here, we describe patterns of PTVs in 1320 genes sequenced in 10,539 healthy controls and 9434 patients with psoriasis, all of Han Chinese ancestry. We identify 8720 PTVs, of which 77% are novel, and estimate 88% of all PTVs are deleterious and subject to purifying selection. Furthermore, we show that individuals with psoriasis have a significantly higher burden of PTVs compared to controls (P = 0.02). Finally, we identified 18 PTVs in 14 genes with unusually high levels of population differentiation, consistent with the action of local adaptation. Our study provides insights into patterns and consequences of PTVs.

4.
Bioorg Med Chem Lett ; 91: 129370, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37301522

RESUMEN

Plinabulin is a promising microtubule destabilizing agent in phase 3 clinical stage for treating non-small cell lung cancer. However, the high toxicity and the poor water solubility of plinabulin limited its use and more plinabulin derivatives need to be explored. Here, two series of 29 plinabulin derivatives were designed, synthesized and evaluated for their anti-tumor effect against three types of cancer cell lines. Most of derivatives exerted obvious inhibition to the proliferation of the cell lines tested. Among them, compound 11c exerted stronger efficiency than plinabulin, and the reason might be the additional hydrogen bond between the nitrogen atom of the indole ring in compound 11c and Gln134 of ß-tubulin. Immunofluorescence assay showed that compound 11c at 10 nM significantly disrupted tubulin structure. Compound 11c also significantly induced G2/M cell cycle arrest and apoptosis in dose dependent manner. These results suggest that compound 11c might be a potential candidate for cancer treatment as antimicrotubule agent.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Tubulina (Proteína)/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Moduladores de Tubulina/química , Neoplasias Pulmonares/tratamiento farmacológico , Antineoplásicos/química , Proliferación Celular , Ensayos de Selección de Medicamentos Antitumorales , Línea Celular Tumoral , Relación Estructura-Actividad , Apoptosis
5.
Org Biomol Chem ; 19(27): 6030-6037, 2021 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-34190307

RESUMEN

Coral-associated microorganisms are likely to play an important role in host defense by the production of antimicrobials. Six new chromanones, namely, phomalichenones H-M (5, 6, and 8-11), and ten known analogues (1-4, 7, and 12-16) were isolated from the coral-associated fungus Parengyodontium album sp. SCSIO 40430. Their structures were elucidated by comprehensive spectroscopic analyses. In addition, the structure of 8 was confirmed by X-ray crystallographic analysis. Resolution using a chiral column showed that each of the compounds 1-8 was an enantiomeric mixture with variable enantiomeric excess (ee) values. Their absolute configurations were determined by a comparison of the experimental and calculated ECD data and by a modified Mosher's method. A plausible biosynthetic scheme was proposed for the production of 1-16. Compounds 2, 3, 13, and 14 were found to be active against Mycobacterium tuberculosis H37Ra with MIC values of 16-64 µg mL-1.


Asunto(s)
Hypocreales
6.
Sensors (Basel) ; 21(5)2021 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-33803461

RESUMEN

With the aim to solve issues of robot object recognition in complex scenes, this paper proposes an object recognition method based on scene text reading. The proposed method simulates human-like behavior and accurately identifies objects with texts through careful reading. First, deep learning models with high accuracy are adopted to detect and recognize text in multi-view. Second, datasets including 102,000 Chinese and English scene text images and their inverse are generated. The F-measure of text detection is improved by 0.4% and the recognition accuracy is improved by 1.26% because the model is trained by these two datasets. Finally, a robot object recognition method is proposed based on the scene text reading. The robot detects and recognizes texts in the image and then stores the recognition results in a text file. When the user gives the robot a fetching instruction, the robot searches for corresponding keywords from the text files and achieves the confidence of multiple objects in the scene image. Then, the object with the maximum confidence is selected as the target. The results show that the robot can accurately distinguish objects with arbitrary shape and category, and it can effectively solve the problem of object recognition in home environments.

7.
World J Microbiol Biotechnol ; 37(1): 16, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33394223

RESUMEN

Succinic acid is a valuable bulk chemical, which has been extensively applied in food, medicine, surfactants and biodegradable plastics industries. As a substitute for chemical raw material, bio-based succinic acid production has received increasing attention due to the depletion of fossil fuels and environmental issues. Meanwhile, the effective bioconversion of lignocellulosic biomass has always been a hot spot of interest owning to the advantages of low expense, abundance and renewability. Consolidated bioprocessing (CBP) is considered to be an alternative approach with outstanding potential, as CBP can not only improve the product yield and productivity, but also reduce the equipment and operating costs. In addition, the current emerging microbial co-cultivation systems provide strong competitiveness for lignocellulose utilization through CBP. This article comprehensively discusses different strategies for the bioconversion of lignocellulose to succinic acid. Based on the principles and technical concepts of CBP, this review focuses on the progress of succinic acid production under different CBP strategies (metabolic engineering based and microbial co-cultivation based). Moreover, the main challenges faced by CBP-based succinic acid fermentation are analyzed, and the future direction of CBP production is prospected.


Asunto(s)
Lignina/metabolismo , Ingeniería Metabólica/métodos , Ácido Succínico/metabolismo , Biomasa , Técnicas de Cocultivo , Fermentación
8.
BMC Bioinformatics ; 21(1): 295, 2020 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-32640979

RESUMEN

BACKGROUND: The human leukocyte antigen (HLA) gene family plays a key role in the immune response and thus is crucial in many biomedical and clinical settings. Utilizing Sanger sequencing, the golden standard technology for HLA typing enables accurate identification of HLA alleles in high-resolution. However, only the commercial software, such as uTYPE, SBT-Assign, and SBTEngine, and very few open-source tools could be applied to perform HLA typing based on Sanger sequencing. RESULTS: We developed a user-friendly, cross-platform and open-source desktop application, known as SOAPTyping, for Sanger-based typing in HLA class I and II alleles. SOAPTyping can produce accurate results with a comprehensible protocol and featured functions. Moreover, SOAPTyping supports a more advanced group-specific sequencing primers (GSSP) module to solve the ambiguous typing results. We used SOAPTyping to analyze 36 samples with known HLA typing from the University of California Los Angeles (UCLA) International HLA DNA Exchange platform and 100 anonymous clinical samples, and the HLA typing results from SOAPTyping are identical to the golden results and 5.5 times faster than commercial software uTYPE, which shows the usability of SOAPTyping. CONCLUSIONS: We introduce the SOAPTyping as the first open-source and cross-platform HLA typing software with the capability of producing high-resolution HLA typing predictions from Sanger sequence data.


Asunto(s)
Antígenos HLA/genética , Prueba de Histocompatibilidad/métodos , Análisis de Secuencia de ADN , Programas Informáticos , Alelos , Cartilla de ADN , Antígenos de Histocompatibilidad Clase I , Antígenos de Histocompatibilidad Clase II , Humanos
9.
Mar Drugs ; 17(5)2019 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-31035725

RESUMEN

Melanoma is one of the most malignant and aggressive types of cancer worldwide. Fibroblast growth factor 2 (FGF2) is one of the critical regulators of melanoma angiogenesis and metastasis; thus, it might be an effective anti-cancer strategy to explore FGF2-targeting drug candidates from existing drugs. In this study, we evaluate the effect of the marine drug propylene glycol alginate sodium sulfate (PSS) on FGF2-mediated angiogenesis and invasion. The data shows that FGF2 selectively bound to PSS with high affinity. PSS inhibited FGF2-mediated angiogenesis in a rat aortic ring model and suppressed FGF2-mediated invasion, but not the migration of murine melanoma B16-F10 cells. The further mechanism study indicates that PSS decreased the expression of activated matrix metalloproteinase 2 (MMP-2) and matrix metalloproteinase 9 (MMP-9), and also suppressed their activity. In addition, PSS was found to decrease the level of Vimentin in B16-F10 cells, which is known to participate in the epithelial-mesenchymal transition. Notably, PSS did not elicit any changes in cancer cell viability. Based on the results above, we conclude that PSS might be a potential drug to regulate the tumor microenvironment in order to facilitate the recovery of melanoma patients.


Asunto(s)
Alginatos/farmacología , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Melanoma Experimental/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológico , Alginatos/uso terapéutico , Animales , Aorta/efectos de los fármacos , Organismos Acuáticos/química , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Embrión de Pollo , Membrana Corioalantoides , Evaluación Preclínica de Medicamentos , Transición Epitelial-Mesenquimal , Humanos , Laminaria/química , Melanoma Experimental/irrigación sanguínea , Melanoma Experimental/patología , Ratones , Invasividad Neoplásica/patología , Invasividad Neoplásica/prevención & control , Neovascularización Patológica/patología , Neovascularización Fisiológica/efectos de los fármacos , Técnicas de Cultivo de Órganos , Ratas , Neoplasias Cutáneas/irrigación sanguínea , Neoplasias Cutáneas/patología , Microambiente Tumoral/efectos de los fármacos
10.
J Neurosci ; 37(1): 152-163, 2017 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-28053038

RESUMEN

Soluble oligomers of amyloid ß-protein (oAß) isolated from the brains of Alzheimer's disease (AD) patients have been shown experimentally (in the absence of amyloid plaques) to impair hippocampal synaptic plasticity, decrease synapses, induce tau hyperphosphorylation and neuritic dystrophy, activate microglial inflammation, and impair memory in normal adult rodents. Nevertheless, there has been controversy about what types of oligomers actually confer these AD-like phenotypes. Here, we show that the vast majority of soluble Aß species obtained from brains of humans who died with confirmed AD elute at high molecular weight (HMW) on nondenaturing size-exclusion chromatography. These species have little or no cytotoxic activity in several bioassays. However, incubation of HMW oAß in mildly alkaline buffer led to their quantitative dissociation into low molecular weight oligomers (∼8-70 kDa), and these were now far more bioactive: they impaired hippocampal LTP, decreased neuronal levels of ß2-adrenergic receptors, and activated microglia in wt mice in vivo Thus, most soluble Aß assemblies in AD cortex are large and inactive but under certain circumstances can dissociate into smaller, highly bioactive species. Insoluble amyloid plaques likely sequester soluble HMW oligomers, limiting their potential to dissociate. We conclude that conditions that destabilize HMW oligomers or retard the sequestration of their smaller, more bioactive components are important drivers of Aß toxicity. Selectively targeting these small, cytotoxic forms should be therapeutically beneficial. SIGNIFICANCE STATEMENT: Oligomers of amyloid ß-protein (oAß) are tought to play an important role in Alzheimer's disease (AD), but there is confusion and controversy about what types and sizes of oligomers have disease-relevant activity. Using size-exclusion chromatography and three distinct measures of bioactivity, we show that the predominant forms of Aß in aqueous extracts of AD brain are high molecular weight (HMW) and relatively inactive. Importantly, under certain conditions, the abundant HMW oAß can dissociate into low molecular weight species, and these low molecular weight oligomers are significantly more bioactive on synapses and microglia than the HMW species from which they are derived. We conclude that conditions that destabilize HMW oAß or retard the sequestration of smaller, more bioactive components are important drivers of Aß toxicity.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/química , Péptidos beta-Amiloides/toxicidad , Química Encefálica , Animales , Cromatografía en Gel , Femenino , Hipocampo/fisiopatología , Humanos , Técnicas In Vitro , Potenciación a Largo Plazo , Masculino , Ratones , Ratones Endogámicos C57BL , Peso Molecular , Receptores Adrenérgicos beta 2/metabolismo , Sinaptosomas/metabolismo
11.
Clin Chem ; 64(4): 715-725, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29545257

RESUMEN

BACKGROUND: Amniocentesis is a common procedure, the primary purpose of which is to collect cells from the fetus to allow testing for abnormal chromosomes, altered chromosomal copy number, or a small number of genes that have small single- to multibase defects. Here we demonstrate the feasibility of generating an accurate whole-genome sequence of a fetus from either the cellular or cell-free DNA (cfDNA) of an amniotic sample. METHODS: cfDNA and DNA isolated from the cell pellet of 31 amniocenteses were sequenced to approximately 50× genome coverage by use of the Complete Genomics nanoarray platform. In a subset of the samples, long fragment read libraries were generated from DNA isolated from cells and sequenced to approximately 100× genome coverage. RESULTS: Concordance of variant calls between the 2 DNA sources and with parental libraries was >96%. Two fetal genomes were found to harbor potentially detrimental variants in chromodomain helicase DNA binding protein 8 (CHD8) and LDL receptor-related protein 1 (LRP1), variations of which have been associated with autism spectrum disorder and keratosis pilaris atrophicans, respectively. We also discovered drug sensitivities and carrier information of fetuses for a variety of diseases. CONCLUSIONS: We were able to elucidate the complete genome sequence of 31 fetuses from amniotic fluid and demonstrate that the cfDNA or DNA from the cell pellet can be analyzed with little difference in quality. We believe that current technologies could analyze this material in a highly accurate and complete manner and that analyses like these should be considered for addition to current amniocentesis procedures.


Asunto(s)
Líquido Amniótico/metabolismo , Feto/metabolismo , Genoma Humano , Secuenciación Completa del Genoma , Anomalías Múltiples/genética , Adulto , Amniocentesis , Trastorno del Espectro Autista/genética , Estudios de Cohortes , Variaciones en el Número de Copia de ADN , Enfermedad de Darier/genética , Cejas/anomalías , Estudios de Factibilidad , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Mutación
12.
J Neurosci ; 36(35): 9041-56, 2016 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-27581448

RESUMEN

UNLABELLED: Microglial dysfunction is increasingly recognized as a key contributor to the pathogenesis of Alzheimer's disease (AD). Environmental enrichment (EE) is well documented to enhance neuronal form and function, but almost nothing is known about whether and how it alters the brain's innate immune system. Here we found that prolonged exposure of naive wild-type mice to EE significantly altered microglial density and branching complexity in the dentate gyrus of hippocampus. In wild-type mice injected intraventricularly with soluble Aß oligomers (oAß) from hAPP-expressing cultured cells, EE prevented several morphological features of microglial inflammation and consistently prevented oAß-mediated mRNA changes in multiple inflammatory genes both in vivo and in primary microglia cultured from the mice. Microdialysis in behaving mice confirmed that EE normalized increases in the extracellular levels of the key cytokines (CCL3, CCL4, TNFα) identified by the mRNA analysis. Moreover, EE prevented the changes in microglial gene expression caused by ventricular injection of oAß extracted directly from AD cerebral cortex. We conclude that EE potently alters the form and function of microglia in a way that prevents their inflammatory response to human oAß, suggesting that prolonged environmental enrichment could protect against AD by modulating the brain's innate immune system. SIGNIFICANCE STATEMENT: Environmental enrichment (EE) is a potential therapy to delay Alzheimer's disease (AD). Microglial inflammation is associated with the progression of AD, but the influence of EE on microglial inflammation is unclear. Here we systematically applied in vivo methods to show that EE alters microglia in the dentate gyrus under physiological conditions and robustly prevents microglial inflammation induced by human Aß oligomers, as shown by neutralized microglial inflammatory morphology, mRNA changes, and brain interstitial fluid cytokine levels. Our findings suggest that EE alters the innate immune system and could serve as a therapeutic approach to AD and provide new targets for drug discovery. Further, we propose that the therapeutic benefits of EE could extend to other neurodegenerative diseases involving microglial inflammation.


Asunto(s)
Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Giro Dentado/patología , Encefalitis/patología , Ambiente , Microglía/metabolismo , Péptidos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/genética , Animales , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Células CHO , Proteínas de Unión al Calcio/metabolismo , Células Cultivadas , Cricetulus , Citocinas/metabolismo , Giro Dentado/fisiopatología , Desoxiuridina/análogos & derivados , Desoxiuridina/metabolismo , Proteínas de Dominio Doblecortina , Humanos , Potenciación a Largo Plazo/efectos de los fármacos , Potenciación a Largo Plazo/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Microdiálisis , Proteínas de Microfilamentos/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Mutación/genética , Neuropéptidos/metabolismo , Fagocitosis/fisiología , ARN Mensajero/metabolismo , Transfección
13.
Immunology ; 152(4): 589-601, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28742222

RESUMEN

Seizures are due to excessive, synchronous neuronal firing in the brain and are characteristic of epilepsy, the fourth most prevalent neurological disease. We report handling-induced and spontaneous seizures in mice deficient for CD39, a cell-surface ATPase highly expressed on microglial cells. CD39-/- mice with handling-induced seizures had normal input-output curves and paired-pulse ratio measured from hippocampal slices and lacked microgliosis, astrogliosis or overt cell loss in the hippocampus and cortex. As expected, however, the cerebrospinal fluid of CD39-/- mice contained increased levels of ATP and decreased levels of adenosine. To determine if immune activation was involved in seizure progression, we challenged mice with lipopolysaccharide (LPS) and measured the effect on microglia activation and seizure severity. Systemic LPS challenge resulted in increased cortical staining of Iba1/CD68 and gene array data from purified microglia predicted increased expression of interleukin-8, triggering receptor expressed on myeloid cells 1, p38, pattern recognition receptors, death receptor, nuclear factor-κB , complement, acute phase, and interleukin-6 signalling pathways in CD39-/- versus CD39+/+ mice. However, LPS treatment did not affect handling-induced seizures. In addition, microglia-specific CD39 deletion in adult mice was not sufficient to cause seizures, suggesting instead that altered expression of CD39 during development or on non-microglial cells such as vascular endothelial cells may promote the seizure phenotype. In summary, we show a correlation between altered extracellular ATP/adenosine ratio and a previously unreported seizure phenotype in CD39-/- mice. This work provides groundwork for further elucidation of the underlying mechanisms of epilepsy.


Asunto(s)
Adenosina Trifosfato/inmunología , Adenosina/inmunología , Apirasa/deficiencia , Corteza Cerebral/inmunología , Hipocampo/inmunología , Convulsiones/inmunología , Adenosina/genética , Adenosina Trifosfato/genética , Animales , Antígenos CD/inmunología , Apirasa/inmunología , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/inmunología , Corteza Cerebral/patología , Hipocampo/patología , Lipopolisacáridos/toxicidad , Ratones , Ratones Noqueados , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/inmunología , Convulsiones/genética , Convulsiones/patología
14.
BMC Cancer ; 17(1): 55, 2017 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-28086832

RESUMEN

BACKGROUND: Norcantharidin (NCTD) is a Chinese FDA approved, chemically synthesized drug for cancer treatment. The effect of NCTD on signaling proteins of EGFR and c-Met was systematically elucidated in current study. METHODS: Two human colon cancer cell lines, HCT116 and HT29, were used as model systems to investigate the anti-cancer molecular mechanism of NCTD. Cell cycle arrest and early/late apoptosis were analyzed by flow cytometry. The levels of EGFR, phospho-EGFR, c-Met, phospho-c-Met and other related proteins were quantified by western blot analysis. RESULTS: NCTD induced cell cycle arrest at G2/M phase in both cell lines. The early and late apoptosis was also observed. Further investigation indicated that NCTD suppressed not only the expression of the total EGFR and the phosphorylated EGFR but also the expression of the total c-Met and the phosphorylated c-Met in colon cancer cells. Moreover, EGFR expression could be mostly restored by co-treatment with MG132, a proteasome inhibitor. In addition, NCTD-induced cell death was comparable to that of the anti-cancer drug gefitinib, a tyrosine kinase inhibitor for EGFR, based on the immunoblot analysis of the expressed proteins after the drug treatment. CONCLUSIONS: NCTD might be a useful and inexpensive drug candidate to substitute for gefitinib to serve the treatment needs of cancer patients.


Asunto(s)
Antineoplásicos/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/tratamiento farmacológico , Receptores ErbB/metabolismo , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-met/metabolismo , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Neoplasias del Colon/metabolismo , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Gefitinib , Células HCT116 , Células HT29 , Humanos , Quinazolinas/farmacología
15.
Neurobiol Dis ; 85: 111-121, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26525100

RESUMEN

Epileptic activity may be more prevalent in early stage Alzheimer's disease (AD) than previously believed. Several studies report spontaneous seizures and interictal discharges in mouse models of AD undergoing age-related Aß accumulation. The mechanism by which Aß-induced neuronal excitability can trigger epileptiform activity remains unknown. Here, we systematically examined field excitatory postsynaptic potentials (fEPSP) in stratum radiatum and population spikes (PSs) in the adjacent stratum pyramidale of CA1 in wild-type mouse hippocampal slices. Soluble Aß oligomers (oAß) blocked hippocampal LTP and EPSP-spike (E-S) potentiation, and these effects were occluded by prior treatment with the glutamate uptake inhibitor TBOA. In accord, oAß elevated glutamate levels in the hippocampal slice medium. Recording the PS revealed that oAß increased PS frequency and reduced LTP, and this LTP deficit was occluded by pretreatment with the GABAA antagonist picrotoxin. Whole-cell recordings showed that oAß significantly increased spontaneous EPSC frequency. Decreasing neuronal activity by increasing GABA tone or partially blocking NMDAR activity prevented oAß impairment of hippocampal LTP. Finally, treating slices with two antiepileptic drugs rescued the LTP inhibition induced by oAß. We conclude that soluble Aß oligomers at the low nanomolar levels present in AD brain increase neuronal excitability by disrupting glutamatergic/GABAergic balance, thereby impairing synaptic plasticity.


Asunto(s)
Péptidos beta-Amiloides/toxicidad , Ácido Glutámico/metabolismo , Hipocampo/fisiopatología , Potenciación a Largo Plazo/fisiología , Ácido gamma-Aminobutírico/metabolismo , Animales , Anticonvulsivantes/farmacología , Células CHO , Cricetulus , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Potenciales Postsinápticos Excitadores/fisiología , Femenino , Hipocampo/efectos de los fármacos , Humanos , Potenciación a Largo Plazo/efectos de los fármacos , Masculino , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Neuronas/efectos de los fármacos , Neuronas/fisiología , Técnicas de Placa-Clamp , Técnicas de Cultivo de Tejidos
16.
J Comput Assist Tomogr ; 40(4): 537-42, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26966954

RESUMEN

PURPOSE: The aim of this study was to analyze the correlation between magnetic resonance imaging-based extramural vascular invasion (EMVI) and the prognostic clinical and histological parameters of stage T3 rectal cancers. METHODS: Eighty-six patients with T3 stage rectal cancer who received surgical resection without neoadjuvant therapy were included. Magnetic resonance imaging-based EMVI scores were determined. Correlations between the scores and pretreatment carcinoembryonic antigen levels, tumor differentiation grade, nodal stage, and vascular endothelial growth factor expression were analyzed using Spearman rank coefficient analysis. RESULTS: Magnetic resonance imaging-based EMVI scores were statistically different (P = 0.001) between histological nodal stages (N0 vs N1 vs N2). Correlations were found between magnetic resonance imaging-based EMVI scores and tumor histological grade (rs = 0.227, P = 0.035), histological nodal stage (rs = 0.524, P < 0.001), and vascular endothelial growth factor expression (rs = 0.422; P = 0.016). CONCLUSIONS: Magnetic resonance imaging-based EMVI score is correlated with prognostic parameters of T3 stage rectal cancers and has the potential to become an imaging biomarker of tumor aggressiveness. Magnetic resonance imaging-based EMVI may be useful in helping the multidisciplinary team to stratify T3 rectal cancer patients for neoadjuvant therapies.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Neovascularización Patológica/diagnóstico por imagen , Neovascularización Patológica/patología , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias , Variaciones Dependientes del Observador , Pronóstico , Sensibilidad y Especificidad , Estadística como Asunto
17.
Front Psychol ; 15: 1288711, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38770260

RESUMEN

Earth Hour, a global mass effort coordinated to show concern for green urban construction and sustainable development, was first organized by the World Wildlife Fund in Australia in 2007 with a growing trend of participation worldwide. However, analysis of participation in Earth Hour based on a large population are sparse, with only a few studies reporting details in positive results without a clear pattern that explains the potential low participation. This study focuses on the non-participants and analyzed the reasons for low participation in Earth Hour using a questionnaire with 401 college students based on the socio-ecological model. Two aspects are explored: (1) social-demographic features; (2) psychosocial traits (environmental awareness, acceptance for law, social support from family and friends and knowledge about the event). Barriers toward participation are included as mediators to explain how these basic features change students' decision on joining large-scale environmental campaign. A participation analysis method using binary logistic regression and one-way MANOVA is applied in data analysis. This study highlights that the irrelevance between students' belief and practice on environmental protection should not be overlooked, and that college students are inclined to join in groups in relevant activities-conversely, herd effect could greatly reduce their willingness to participation. The findings of this study have wider implications for school educators, practitioners and organizations involved in pro-environmental career. This paper highlights that, from an international perspective, the essence of collective action with a similar nature to Earth Hour and contributes to a global dialogue on fostering sustainable behaviors.

18.
J Biol Chem ; 287(36): 30812-22, 2012 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-22822074

RESUMEN

APOBEC3A belongs to a family of single-stranded DNA (ssDNA) DNA cytosine deaminases that are known for restriction of HIV through deamination-induced mutational inactivation, e.g. APOBEC3G, or initiation of somatic hypermutation and class switch recombination (activation-induced cytidine deaminase). APOBEC3A, which is localized to both the cytoplasm and nucleus, not only restricts HIV but can also initiate catabolism of cellular DNA. Despite being ascribed these roles, there is a paucity of data available on the biochemical mechanism by which APOBEC3A deaminates ssDNA. Here we assessed APOBEC3A deamination activity on ssDNA and in dynamic systems modeling HIV replication (cytoplasmic event) and DNA transcription (nuclear event). We find that APOBEC3A, unlike the highly processive APOBEC3G, exhibits low or no processivity when deaminating synthetic ssDNA substrates with two cytosines located 5-63 nucleotides apart, likely because of an apparent K(d) in the micromolar range (9.1 µm). APOBEC3A was able to deaminate nascently synthesized (-)DNA in an in vitro model HIV replication assay but induced fewer mutations overall in comparison to APOBEC3G. However, the data indicate that the target deamination motif (5'-TC for APOBEC3A and 5'-CC for APOBEC3G) and not the number of mutations best predicted the ability to mutationally inactivate HIV. We further assessed APOBEC3A for the ability to deaminate dsDNA undergoing transcription, which could allow for collateral deaminations to occur in genomic DNA similar to the action of activation-induced cytidine deaminase. That APOBEC3A was able to deaminate dsDNA undergoing transcription suggests a genomic cost of a deamination-based retroviral restriction system.


Asunto(s)
Núcleo Celular/enzimología , Citidina Desaminasa/metabolismo , Citoplasma/enzimología , ADN Viral/metabolismo , VIH-1/fisiología , Proteínas/metabolismo , Replicación Viral/fisiología , Desaminasa APOBEC-3G , Núcleo Celular/genética , Citidina Desaminasa/genética , Citoplasma/genética , ADN Viral/genética , Humanos , Mutación , Proteínas/genética , Transcripción Genética/genética
19.
Fluids Barriers CNS ; 20(1): 45, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37328833

RESUMEN

Regulation of the volume and electrolyte composition of the cerebrospinal fluid (CSF) is vital for brain development and function. The Na-K-Cl co-transporter NKCC1 in the choroid plexus (ChP) plays key roles in regulating CSF volume by co-transporting ions and mediating same-direction water movements. Our previous study showed ChP NKCC1 is highly phosphorylated in neonatal mice as the CSF K+ level drastically decreases and that overexpression of NKCC1 in the ChP accelerates CSF K+ clearance and reduces ventricle size [1]. These data suggest that NKCC1 mediates CSF K+ clearance following birth in mice. In this current study, we used CRISPR technology to create a conditional NKCC1 knockout mouse line and evaluated CSF K+ by Inductively Coupled Plasma Optical Emission spectroscopy (ICP-OES). We demonstrated ChP-specific reduction of total and phosphorylated NKCC1 in neonatal mice following embryonic intraventricular delivery of Cre recombinase using AAV2/5. ChP-NKCC1 knockdown was accompanied by a delayed perinatal clearance of CSF K+. No gross morphological disruptions were observed in the cerebral cortex. We extended our previous results by showing embryonic and perinatal rats shared key characteristics with mice, including decreased ChP NKCC1 expression level, increased ChP NKCC1 phosphorylation state, and increased CSF K+ levels compared to adult. Collectively, these follow up data support ChP NKCC1's role in age-appropriate CSF K+ clearance during neonatal development.


Asunto(s)
Plexo Coroideo , Potasio , Miembro 2 de la Familia de Transportadores de Soluto 12 , Animales , Femenino , Ratones , Embarazo , Ratas , Corteza Cerebral/metabolismo , Ventrículos Cerebrales/metabolismo , Líquido Cefalorraquídeo/metabolismo , Plexo Coroideo/metabolismo , Potasio/metabolismo , Miembro 2 de la Familia de Transportadores de Soluto 12/metabolismo
20.
Sci Rep ; 13(1): 19054, 2023 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-37925582

RESUMEN

It is of much importance to clarify the impact of technological innovation on carbon emission intensity for the low-carbon transformation of China's economy. This study, based on the panel data of 30 Chinese provinces and municipalities from 2010 to 2020, measures and analyzes the carbon emission intensity and the level of technological innovation, establishing a spatial econometric model to study the spatial spillover effect and a panel threshold model to analyze the nonlinear influence of technological innovation level on carbon emission intensity. The findings are as follows: First, the overall carbon emission intensity in China shows a decreasing trend from 2010 to 2020, with the average dropping from 3.09 in 2010 to 1.98 in 2020; Second, the spatial autocorrelation results reveal that the level of technological innovation and carbon emission intensity in China are obviously aggregated in the global spatial distribution pattern. Third, the regression results of the spatial econometric model show that the direct effect of technological innovation on carbon emission intensity is significantly negative at the level of 1%, that is, the improvement of the technological innovation in a certain area has a significant inhibitory effect on carbon emission intensity. Fourth, based on the level of economic development, there is a significant three-threshold effect of the level of technological innovation on carbon emission intensity in China, and the influence of the level of technological innovation on carbon emission intensity varies in the direction of existence and coefficient values within different threshold intervals. As economic development reaches the third interval, the technological innovation level has the most significant inhibition on carbon emission intensity. These findings enriches the research of the nonlinear relationship between technological innovation and carbon emission intensity, clarifies the spatial spillover effect and threshold effect between among them, and provides inspiration for better promote the low-carbon transformation of economy.

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