Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Phys Chem Chem Phys ; 26(5): 3810-3814, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-37955161

RESUMO

We report on molecular dynamics simulation evidence revealing that an oligomer additive can be used to greatly facilitate the self-assembly of a bisurea in organic solvent media, through the initial regular packing and the subsequent stiffening of the self-assembly filament. The underlying physics is attributed to the substantially reduced diffusivities of the solute and, in particular, solvent molecules, featuring a generally weakened (thermal) Brownian force under ambient conditions. Without such oligomer-induced molecular cooling-in contrast to the usual external cooling, the original solvent medium is noted to foster instead more stabilized and disordered aggregates and, in particular, it would require a temperature reduction that is practically inaccessible in order to sustain similar stiffness of the self-assembly filament. These features, in accord with recent experimental observations, highlight the open opportunity of promoting the self-assembly of small functional molecules in general solvent media without requiring substantial changes of the system temperature, as is crucial for many practical applications including the biological/biomedical ones.

2.
Front Cell Neurosci ; 17: 1187400, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37448698

RESUMO

Purpose: To investigate the relationship between the intraocular levels of complement proteins and myopia-related retinal neuronal and vascular degeneration. Methods: Aqueous humour from 147 myopic patients, including 60 low-myopia and 87 high-myopia were collected during Implantable Collamer Lens implantation surgery. All participants received comprehensive ophthalmic examinations, including logMAR best corrected visual acuity, axial length measurement, fundus photography and ocular B-scan ultrasonography. The myopic eyes were further classified into simple myopia (SM, n = 78), myopic posterior staphyloma (PS, n = 39) and PS with myopic chorioretinal atrophy (PS + CA, n = 30). Retinal thickness and vascular density in the macula (6 mm × 6 mm) and optic nerve head (4.5 mm × 4.5 mm) were measured using Optical Coherence Tomography (OCT) and OCT angiography (OCTA). The levels of complement proteins including C1q, C3, C3b/iC3b, C4, CFB, CFH, C2, C4b, C5, C5a, CFD, MBL and CFI in the aqueous humour were measured using the Luminex Multiplexing system. The real-time RT-PCR was conducted to examine the expression of complement genes (C1q, C2, C3, C4, CFI and CFD) in the guinea pig model of long-term form deprivation-induced myopic retinal degeneration. Results: OCTA showed that retinal neuronal thickness and vascular density in superficial and deep layers of the macular zone as well as vascular density in the optic nerve head were progressively decreased from SM to PS and PS + CA (p < 0.05). The aqueous humour levels of C1q, C3, C3b/iC3b, C4, CFB, CFH, C2, C4b, C5 and CFI were significantly higher in high-myopic eyes compared to those in low-myopic eyes. Further subgroup analysis revealed the highest levels of complement components/fragments in the PS + CA group. The intraocular levels of complement factors particularly C3b/iC3b and C4 were negatively correlated with macular zone deep layer retinal thickness and vascular density and optic nerve head vascular density. The expression of C2, C3 and C4 genes was significantly higher in guinea pig eyes with myopic retinal degeneration compared to control eyes. Conclusions: The intraocular classical pathway and alternative pathway of the complement system are partially activated in pathological myopia. Their activation is related to the degeneration of retinal neurons and the vasculature in the macula and the vasculature in the optic nerve head.

3.
J Affect Disord ; 323: 219-231, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36410454

RESUMO

BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) is a widely available treatment for major depression, but its efficacy and tolerability are uncertain for patients with late-life depression (LLD). To assess the existing evidence of rTMS for LLD treatment, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) according to PRISMA guidelines. METHODS: We retrieved RCTs from four databases published between 1 January 2000 and 10 September 2021 comparing the effects of active and sham stimulation in LLD patients. We performed subgroup analyses to examine the impact of different parameters. The primary outcomes were the response and discontinuation rates of rTMS for LLD patients, representing for efficacy and tolerability, respectively. Secondary outcomes were remission and dropout rates. Discontinuation referred to patients who withdrew for any reason, while dropout referred to participants who withdrew early because of adverse events. RESULTS: Nine articles describing 11 studies (two articles each contained two studies) met the eligibility criteria. All outcomes were analyzed using a random-effects model. The summary analysis of nine suitable RCTs revealed a cumulative response rate of 2.86 (95 % confidence interval (95 % CI), 1.87-4.37) and a remission rate of 4.02 (95 % CI, 1.83-8.81) in the active group compared to the sham group. The pooled odds ratios (ORs) for discontinuation and dropout rates were not significantly different between the two groups. In addition, some rTMS parameters were associated with better efficacy. CONCLUSIONS: The meta-analysis suggested that rTMS is an effective, well-tolerated treatment for patients with LLD. Future efforts should enhance study methodologies to improve their efficacy and increase the homogeneity of rTMS parameters to promote comparability between studies.


Assuntos
Transtorno Depressivo Maior , Estimulação Magnética Transcraniana , Humanos , Estimulação Magnética Transcraniana/efeitos adversos , Estimulação Magnética Transcraniana/métodos , Depressão , Transtorno Depressivo Maior/terapia , Transtorno Depressivo Maior/etiologia , Resultado do Tratamento , Razão de Chances
4.
J Inequal Appl ; 2017(1): 35, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28216990

RESUMO

In this paper, the algorithm for large-scale nonlinear equations is designed by the following steps: (i) a conjugate gradient (CG) algorithm is designed as a sub-algorithm to obtain the initial points of the main algorithm, where the sub-algorithm's initial point does not have any restrictions; (ii) a quasi-Newton algorithm with the initial points given by sub-algorithm is defined as main algorithm, where a new nonmonotone line search technique is presented to get the step length [Formula: see text]. The given nonmonotone line search technique can avoid computing the Jacobian matrix. The global convergence and the [Formula: see text]-order convergent rate of the main algorithm are established under suitable conditions. Numerical results show that the proposed method is competitive with a similar method for large-scale problems.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...