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1.
Metallomics ; 16(1)2024 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-38178638

RESUMEN

Demyelination within the central nervous system (CNS) is a significant feature of debilitating neurological diseases such as multiple sclerosis and administering the copper-selective chelatorcuprizone to mice is widely used to model demyelination in vivo. Conspicuous demyelination within the corpus callosum is generally attributed to cuprizone's ability to restrict copper availability in this vulnerable brain region. However, the small number of studies that have assessed copper in brain tissue from cuprizone-treated mice have produced seemingly conflicting outcomes, leaving the role of CNS copper availability in demyelination unresolved. Herein we describe our assessment of copper concentrations in brain samples from mice treated with cuprizone for 40 d. Importantly, we applied an inductively coupled plasma mass spectrometry methodology that enabled assessment of copper partitioned into soluble and insoluble fractions within distinct brain regions, including the corpus callosum. Our results show that cuprizone-induced demyelination in the corpus callosum was associated with decreased soluble copper in this brain region. Insoluble copper in the corpus callosum was unaffected, as were pools of soluble and insoluble copper in other brain regions. Treatment with the blood-brain barrier permeant copper compound CuII(atsm) increased brain copper levels and this was most pronounced in the soluble fraction of the corpus callosum. This effect was associated with significant mitigation of cuprizone-induced demyelination. These results provide support for the involvement of decreased CNS copper availability in demyelination in the cuprizone model. Relevance to human demyelinating disease is discussed.


Asunto(s)
Cuprizona , Enfermedades Desmielinizantes , Humanos , Animales , Ratones , Cuprizona/efectos adversos , Cuerpo Calloso , Enfermedades Desmielinizantes/inducido químicamente , Enfermedades Desmielinizantes/tratamiento farmacológico , Cobre/farmacología , Oligodendroglía , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Vaina de Mielina
2.
Ann N Y Acad Sci ; 1521(1): 140-154, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36718543

RESUMEN

Uncovering the genetic underpinnings of musical ability and engagement is a foundational step for exploring their wide-ranging associations with cognition, health, and neurodevelopment. Prior studies have focused on using twin and family designs, demonstrating moderate heritability of musical phenotypes. The current study used genome-wide complex trait analysis and polygenic score (PGS) approaches utilizing genotype data to examine genetic influences on two musicality traits (rhythmic perception and music engagement) in N = 1792 unrelated adults in the Vanderbilt Online Musicality Study. Meta-analyzed heritability estimates (including a replication sample of Swedish individuals) were 31% for rhythmic perception and 12% for self-reported music engagement. A PGS derived from a recent study on beat synchronization ability predicted both rhythmic perception (ß = 0.11) and music engagement (ß = 0.19) in our sample, suggesting that genetic influences underlying self-reported beat synchronization ability also influence individuals' rhythmic discrimination aptitude and the degree to which they engage in music. Cross-trait analyses revealed a modest contribution of PGSs from several nonmusical traits (from the cognitive, personality, and circadian chronotype domains) to individual differences in musicality (ß = -0.06 to 0.07). This work sheds light on the complex relationship between the genetic architecture of musical rhythm processing, beat synchronization, music engagement, and other nonmusical traits.


Asunto(s)
Música , Cognición , Individualidad , Fenotipo , Percepción , Percepción Auditiva
3.
Front Neurosci ; 16: 765945, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35221896

RESUMEN

Prosody perception is fundamental to spoken language communication as it supports comprehension, pragmatics, morphosyntactic parsing of speech streams, and phonological awareness. A particular aspect of prosody: perceptual sensitivity to speech rhythm patterns in words (i.e., lexical stress sensitivity), is also a robust predictor of reading skills, though it has received much less attention than phonological awareness in the literature. Given the importance of prosody and reading in educational outcomes, reliable and valid tools are needed to conduct large-scale health and genetic investigations of individual differences in prosody, as groundwork for investigating the biological underpinnings of the relationship between prosody and reading. Motivated by this need, we present the Test of Prosody via Syllable Emphasis ("TOPsy") and highlight its merits as a phenotyping tool to measure lexical stress sensitivity in as little as 10 min, in scalable internet-based cohorts. In this 28-item speech rhythm perception test [modeled after the stress identification test from Wade-Woolley (2016)], participants listen to multi-syllabic spoken words and are asked to identify lexical stress patterns. Psychometric analyses in a large internet-based sample shows excellent reliability, and predictive validity for self-reported difficulties with speech-language, reading, and musical beat synchronization. Further, items loaded onto two distinct factors corresponding to initially stressed vs. non-initially stressed words. These results are consistent with previous reports that speech rhythm perception abilities correlate with musical rhythm sensitivity and speech-language/reading skills, and are implicated in reading disorders (e.g., dyslexia). We conclude that TOPsy can serve as a useful tool for studying prosodic perception at large scales in a variety of different settings, and importantly can act as a validated brief phenotype for future investigations of the genetic architecture of prosodic perception, and its relationship to educational outcomes.

4.
Sci Rep ; 11(1): 11782, 2021 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-34083644

RESUMEN

The clinical efficacy of adjuvant radiotherapy in sigmoid colon cancer remains questioned. To evaluate the clinical efficacy of adjuvant external beam radiotherapy (EBRT) for patients with pathologic stage T4b sigmoid colon cancer. Patients with stage pT4b sigmoid colon cancer receiving adjuvant EBRT or not followed by surgery between 2004 and 2016 were extracted from the Surveillance, Epidemiology, and End Results database. Analysis of overall survival (OS) was performed using Kaplan-Meier curves and prognostic factors were identified using Cox proportional hazards regression models with 95% confidence intervals within the entire cohort. A risk-stratification system was then developed based on the ß regression coefficient. Among 2073 patients, 284 (13.7%) underwent adjuvant EBRT. The median OS in the group receiving adjuvant EBRT was significantly longer than that in the non-radiotherapy group (p < 0.001). Age, serum carcinoembryonic antigen (CEA) level, perineural invasion, lymph node dissection (LND) number, and adjuvant EBRT were independent factors associated with OS. A risk-stratification system was generated, which showed that low-risk patients had a higher 5-year survival rate than high-risk patients (75.6% vs. 42.3%, p < 0.001). Adjuvant EBRT significantly prolonged the 5-year survival rate of high-risk patients (62.6% vs. 38.3%, p = 0.009) but showed no survival benefit among low-risk patients (87.7% vs. 73.2%, p = 0.100). Our risk-stratification model comprising age, serum CEA, perineural invasion, and LND number predicted the outcomes of patients with stage pT4b sigmoid colon cancer based on which subgroup of high-risk patients should receive adjuvant EBRT.


Asunto(s)
Braquiterapia/métodos , Neoplasias del Colon Sigmoide/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Estimación de Kaplan-Meier , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Curva ROC , Radioterapia Adyuvante , Estudios Retrospectivos , Programa de VERF , Neoplasias del Colon Sigmoide/diagnóstico , Neoplasias del Colon Sigmoide/mortalidad , Resultado del Tratamiento
5.
Cancer Control ; 27(2): 1073274820936287, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32614270

RESUMEN

To evaluate whether high biologically effective dose (BED) radiotherapy improves local control and survival outcomes for patients with brain metastases (BMs) from small-cell lung cancer (SCLC) and to determine possible prognostic factors. From January 1998 to June 2018, 250 patients with BM from SCLC were retrospectively analyzed. The Cutoff Finder program was used to classify patients by BED. Overall survival (OS) and BM progression-free survival (BM-PFS) were analyzed using the Kaplan-Meier method and log-rank test. A Cox regression model was used to calculate the hazard ratio and 95% CI for prognostic factors for OS among the study population and propensity score (PS)-matched patients. A BED of 47.4 was taken as the optimal cutoff value. Both OS and BM-PFS were significantly improved in the high-BED (>47.4 Gy) than in the low-BED (≤47.4 Gy) group (median OS: 17.5 months vs 9.5 months, P < .001, median BM-PFS: 14.4 months vs 8.3 months, P < .001). Biologically effective dose (P < .001), Eastern Cooperative Oncology Group performance status (P = .047), smoking (P = .005), and pleural effusion (P = .004) were independent prognostic factors for OS. Propensity score matching with a ratio of 1:2 resulted in 57 patients in the high-BED group and 106 patients in the low-BED group. In the PS-matched cohort, OS and BM-PFS were significantly prolonged in the high-BED group compared with the low-BED group (P < .001). Biologically effective dose >47.4 Gy improves survival among patients with BM from SCLC. Eastern Cooperative Oncology Group score, smoking, and pleural effusion independently affect OS of SCLC patients with BM.


Asunto(s)
Neoplasias Encefálicas/mortalidad , Neoplasias Pulmonares/mortalidad , Recurrencia Local de Neoplasia/mortalidad , Radioterapia/mortalidad , Carcinoma Pulmonar de Células Pequeñas/mortalidad , Adulto , Anciano , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/radioterapia , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/radioterapia , Pronóstico , Puntaje de Propensión , Dosificación Radioterapéutica , Estudios Retrospectivos , Carcinoma Pulmonar de Células Pequeñas/patología , Carcinoma Pulmonar de Células Pequeñas/radioterapia , Tasa de Supervivencia
6.
ESMO Open ; 5(2)2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32253246

RESUMEN

OBJECTIVE: The prediction of survival of gastric neuroendocrine tumours (g-NETs) is controversial. Prognostic effects of the metastatic lymph node ratio (LNR) in patients with g-NET were explored, and a nomogram was plotted to predict the survival rates of patients. METHODS: A longitudinal study conducted on the basis of the Surveillance, Epidemiology, and End Results database. The association between LNR and survival were investigated by using Pearson correlation and Cox regression. Overall survival (OS) and cancer-specific survival (CSS) rates were predicted with the help of nomograms. RESULTS: A total of 315 patients with g-NET diagnosed from 2004 to 2015 were included in this study. LNR was discovered to have a negative correlation with OS and CSS (Pearson correlation coefficients: 0.343 (p<0.001) and 0.389 (p<0.001), respectively). The multivariate analyses indicated age, tumour site, differentiation, T staging, M staging, chemotherapy and LNR to be independent prognostic factors for both OS and CSS. Surgery was also a prognostic determinant for CSS (p=0.003). Concordance indices of the nomograms for OS and CSS were higher than those of the TNM classification (0.772 vs 0.730 and 0.807 vs 0.768, respectively). As per the area under the receiver operating characteristic curve, predictive ability of the nomograms for survival of 1, 3 and 5 years was all better than that of TNM classification. CONCLUSIONS: LNR is an independent predictor of g-NETs. The nomograms plotted in this study have a satisfying predictive ability of survival risks and are capable of guiding tailored treatment strategies for patients with g-NET.


Asunto(s)
Neoplasias Intestinales/patología , Índice Ganglionar/métodos , Tumores Neuroendocrinos/patología , Neoplasias Pancreáticas/patología , Programa de VERF/normas , Neoplasias Gástricas/patología , Bases de Datos Factuales , Femenino , Humanos , Neoplasias Intestinales/mortalidad , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/mortalidad , Nomogramas , Neoplasias Pancreáticas/mortalidad , Pronóstico , Neoplasias Gástricas/mortalidad , Análisis de Supervivencia
7.
Dalton Trans ; 48(25): 9181-9186, 2019 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-31149684

RESUMEN

The reaction mechanism of the Ru(ii)-catalyzed regioselective C-H allylation of indoles with allyl alcohols has been studied by density functional theory (DFT) calculations. This reaction mechanism involves five major steps: deprotonation of amide-NH, arene C-H activation, allyl alcohol insertion, ß-OH elimination and protonation. Our calculation results indicate that C2-H bond allylation is better than C7-H bond allylation, which can be attributed to the stronger nucleophilicity of C2 compared to C7 in the C-Ru bond insertion of indole substrates. Furthermore, we also suggest that C-Ru bond insertion is more favorable than N-Ru bond insertion, which can be attributed to the different hybridization states of the relevant carbon and nitrogen atoms. Meanwhile, we also illustrate that the substrate cinnamyl alcohol cannot give the desired product due to the steric hindrance of the phenyl ring in cinnamyl alcohol with the indole skeleton.

8.
Dalton Trans ; 47(41): 14644-14651, 2018 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-30277238

RESUMEN

The reaction mechanism of the Pd2+-catalyzed regioselective C(sp2)-H acylation of azoxybenzenes with α-oxocarboxylic acids has been studied by density functional theory (DFT) calculations. This reaction mechanism involves five major steps: C-H activation, deprotonation, decarboxylation, reductive elimination and oxidation. Our calculation results indicate that the N-coordinated pathway is better than the O-coordinated pathway, which can be interpreted by distortion-interaction analysis of the C-H bond activation transition states. Furthermore, we also suggest that the C-H bond acylation of aryl 1 is more favorable than that of aryl 2, which can be attributed to the fact that five-membered ring transition states are more favorable than four-membered ring transition states and the ON-group has positive charge.

9.
Org Lett ; 15(18): 4670-3, 2013 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-24024875

RESUMEN

Simply by introducing steric side chains, the shape-persistent cyclo[6]aramides were found to exhibit nonaggregational behavior and strong association (3 × 10(4) M(-1)) ability in acetone for binding secondary ammonium salt. The complexation can be switched in an on-and-off fashion using AgPF6 and TBACl, contrasting sharply with their corresponding acyclic pentamer and demonstrating the macrocyclic effect.


Asunto(s)
Modelos Moleculares , Compuestos Policíclicos/química , Compuestos de Amonio Cuaternario/química , Acetona/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Sales (Química)/química , Relación Estructura-Actividad
10.
Org Biomol Chem ; 11(40): 6975-83, 2013 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-24057168

RESUMEN

A new class of imide- and urea-based hetero-strands with a quadruple ADDA/DAAD hydrogen-bond array was designed and synthesized from easily accessible starting materials. The molecular recognition between the two different strands depends highly on the substituents and the linker between neighboring hydrogen-bonds, which results in the stability of these heteroduplexes varying from 10(3) to >10(5) M(-1) in apolar solvents. In particular, an increase of the association constant by up to one order of magnitude was observed by derivatizing the ADDA arrays at the termini with electron-withdrawing groups. Molecular modelling of the representative complementary complexes reveals the binding mode of four hydrogen-bond arrays that agrees with the matched pair.

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