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1.
Front Neurol ; 15: 1300459, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38361643

RESUMO

Background: Sleep disturbances are an early indicator of cognitive impairment and exacerbate its progression. While pharmacological treatments for sleep disorders exist, their side-effect profile includes an increased risk of falls and the potential to exacerbate cognitive impairment. Non-pharmacological treatments such as physical exercise should be considered. However, uncertainties persist. We aimed to assess the potential benefits of exercise interventions on sleep in patients with cognitive impairment and determine the specific effects of various exercise modalities. Materials and methods: A systematic search was performed on seven databases for eligible studies published before Nov 2022. Randomized controlled trials of exercise for patients with cognitive impairment (mild cognitive impairment and Alzheimer's disease) were included. All analyses were conducted using RevMan version 5.4. Meta-analysis and The Grading of Recommendations Assessment Development and Evaluations (GRADE) quality ratings were performed on sleep quality and objective sleep data. Results: A total of 8 randomized controlled trials were included with a sample size of 486 subjects. For patients with cognitive impairment, physical exercise had a beneficial effect on sleep quality [MD = -3.55 (-5.57, -1.32), Z = 3.13, p = 0.002] and total sleep time [MD = 33.77 (23.92, 43.62), Z = 6.72, P < 0.00001]. No improvement was found in sleep efficiency and nocturnal awakening time. Subgroup analysis showed that multi-component exercise produced superior results. Conclusion: Physical exercise may improve sleep quality and total sleep time for patients with cognitive impairment. Multi-component exercise designed individually is more effective. Large-scale randomized controlled trials with objective sleep outcome measurements are warranted.Clinical trial registration: https://www.crd.york.ac.uk/prospero/, identifier: CRD42022377221.

2.
Sci Rep ; 13(1): 9752, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37328537

RESUMO

An expanded-sandwich system is a nonlinear extended block-oriented system in which memoryless elements in conventional block-oriented systems are displaced by memory submodels. Expanded-sandwich system identification has received extensive attention in recent years due to the powerful ability of these systems to describe actual industrial systems. This study proposes a novel recursive identification algorithm for an expanded-sandwich system, in which an estimator is developed on the basis of parameter identification error data rather than the traditional prediction error output information. In this scheme, a filter is introduced to extract the available system information based on miserly structure layout, and some intermediate variables are designed using filtered vectors. According to the developed intermediate variables, the parameter identification error data can be obtained. Thereafter, an adaptive estimator is established by integrating the identification error data compared with the classic adaptive estimator based on the prediction error output information. Thus, the design framework introduced in this research provides a new perspective for the design of identification algorithms. Under a general continuous excitation condition, the parameter estimation values can converge to the true values. Finally, experimental results and illustrative examples indicate the availability and usefulness of the proposed method.

3.
Front Aging Neurosci ; 14: 963845, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36062146

RESUMO

Background: Plasma-derived ß-amyloid, tau, and neurodegeneration (ATN) biomarkers can accurately diagnose Alzheimer's disease (AD) and predict its progression. Few studies have investigated the relationship between plasma biomarkers and changes in plasma inflammatory markers in clinically diagnosed AD. Methods: Seventy-four participants were recruited, including 30 mild-to-moderate AD dementia patients and 44 normal controls (NC). All participants underwent neuropsychological testing and blood sampling for biomarker testing. AD was clinically diagnosed according to the National Institute on Aging-Alzheimer's Association (NIA-AA) core criteria and required age-mismatched hippocampal atrophy. We performed Single Molecule Array (Simoa), an ultra-sensitive enzyme-linked immunosorbent assay (ELISA), to examine plasma ATN markers, including ß-amyloid (Aß) 40, Aß42, p-tau181, total (t)-tau, neurofilament protein light chain (NfL), and inflammatory factors (TNF-α, IL-1ß, IL-6, and IL-8). Results: The level of the plasma Aß42/Aß40 ratio was significantly declined and the levels of the plasma p-tau181, NfL and TNF-α were significantly higher in the AD group than the NC group, but there was no significant difference in the levels of plasma t-tau, IL-1ß, IL-6, and IL-8 between the AD and NC groups. The levels of plasma p-tau181, NfL, Aß42/Aß40 ratio, and TNF-α were all associated with impairments in multiple cognitive domains. Among them, the plasma Aß42/Aß40 ratio, and the p-tau181 and TNF-α levels were associated with impairments in global cognition, memory, and visuospatial abilities, but not with executive function, only plasma NfL level was associated with executive function. Plasma NfL showed higher diagnostic performance in AD than in NC individuals (AUC = 0.833). A combined diagnostic prediction model of plasma Aß42/Aß40 ratio, p-tau 181, and NfL had the highest value than each factor alone (AUC = 0.902),with a sensitivity and specificity of 0.867 and 0.886, respectively. Conclusion: The levels of plasma ATN biomarkers (Aß42/Aß40 ratio, p-tua181, and NfL) were significantly changed in clinically diagnosed AD patients and they all associated with different domains of cognitive impairment. Plasma ATN biomarkers better differentiate mild-to-moderate AD dementia from NC when they are incorporated into diagnostic models together rather than individually. Plasma ATN biomarkers have the potential to be a screening tool for AD. However, the expression of inflammatory factors in AD patients requires further research.

4.
Biomaterials ; 280: 121310, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34890972

RESUMO

Radial glia (RG) cells that align in parallel in the embryonic brain are found to be able to guide the directed migration of neurons in response to brain injury. Therefore, biomaterials with aligned architectures are supposed to have positive effects on neural migration and neurogenic differentiation for brain injury repair that are rarely addressed, although they have been widely demonstrated in spinal cord and peripheral nerve system. Here, we present a highly biomimetic scaffold of aligned fibrin hydrogel (AFG) that mimics the oriented structure of RG fibers. Through a combination of histological, behavioral, imaging, and transcriptomic analyses, we demonstrated that transplanting the AFG scaffold into injured cortical brains promotes effective migration, differentiation, and maturation of endogenous neural stem cells, resulting in neurological functional recovery. Therefore, this study will light up a new perspective on applying an aligned scaffold to promote cortical regeneration after injury by inducing endogenous neurogenesis.


Assuntos
Lesões Encefálicas , Células-Tronco Neurais , Traumatismos da Medula Espinal , Encéfalo/patologia , Lesões Encefálicas/terapia , Diferenciação Celular , Humanos , Células-Tronco Neurais/patologia , Neurogênese , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/terapia
5.
Sci Total Environ ; 772: 145039, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33770902

RESUMO

There has been much debate on the temporal change trend and existence of a turning point in spring green-up date (GUD) of plants on the Qinghai-Tibetan Plateau (QTP). Most previous studies on the QTP used remote sensing data, which have large uncertainties. In this study, using a large amount of long-term ground observation data at 27 phenological stations across the QTP (1694 GUD records), we showed that on the whole, QTP herbaceous plant GUD insignificantly advanced during 1982-2017. Although the direction of the GUD trend did not change from 1982 to 2017, the magnitude of the advancing trend greatly weakened after 1999. According to our estimated results from 28 paired GUD time series, the overall GUD trend shifted from -2.70 days/decade during 1982-1999 to -0.56 days/decade during 2000-2017. This finding contrasts with the conclusions of previous satellite-based studies, which either reported a continuous significant advancement of GUD or a turning point in the mid-to-late 1990s. Through partial correlation analysis and partial least squares regression, we found that winter and spring air temperatures were the primary climatic factors that influenced the temporal change in GUD, and both had negative effects on GUD. The decreased GUD trend was mainly attributable to the warming slowdown in spring. On average, the spring warming rate decreased by 52.43% after 1999, whereas the winter warming rate displayed no obvious change. This study also found that the GUD of forbs showed stronger sensitivity to air temperature change than that of sedges and grasses. This indicates that forbs are more competitive in adaptation to climate warming, which might shift plant community structure and affect ecosystem service function. Moreover, the declined advancement in GUD implies that the spring phenologically driven increase in carbon uptake may have also slowed in the past two decades.


Assuntos
Mudança Climática , Ecossistema , Estações do Ano , Temperatura , Tibet
6.
Ann Thorac Surg ; 110(5): e441-e443, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32492438

RESUMO

Because the segmental bronchi and vessels are commonly variable and complicated, it is difficult to correctly identify them. Misidentification of the segmental anatomy could result in the failure of segmentectomy and conversion to other surgical procedures such as bisegmentectomy or lobectomy. We describe a novel method to identify the target segmental vessels and bronchi by exposing the adjacent segmental anatomy during uniportal video-assisted thoracoscopic segmentectomy, which could help to reduce the chance of misidentification.


Assuntos
Neoplasias Pulmonares/cirurgia , Pneumonectomia/métodos , Cirurgia Torácica Vídeoassistida/métodos , Angiografia , Broncografia , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia Computadorizada por Raios X
7.
Eur Spine J ; 29(8): 2105, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32577863

RESUMO

Zhao-he and Sun-qingling are the co-first authors for this manuscript in the initial submission. Because of author's negligence and fault, this information was not shown clearly in the originally published article.

8.
J Invest Surg ; 33(2): 172-180, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29672183

RESUMO

Background: Peripheral nerve injury (PNI) has devastating consequences. Dorsal root ganglion as a pivotal locus participates in the process of neuropathic pain and nerve regeneration. In recent years, gene sequencing technology has seen rapid rise in the biomedicine field. So, we attempt to gain insight into in the mechanism of neuropathic pain and nerve regeneration in the transcriptional level and to explore novel genes through bioinformatics analysis. Methods: The gene expression profiles of GSE96051 were downloaded from GEO database. The gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) enrichment analyses were performed, and protein-protein interaction (PPI) network of the differentially expressed genes (DEGs) was constructed by Cytoscape software. Results: Our results showed that both IL-6 and Jun genes and the signaling pathway of MAPK, apoptosis, P53 present their vital modulatory role in nerve regeneration and neuropathic pain. Noteworthy, 13 hub genes associated with neuropathic pain and nerve regeneration, including Ccl12, Ppp1r15a, Cdkn1a, Atf3, Nts, Dusp1, Ccl7, Csf, Gadd45a, Serpine1, Timp1 were rarely reported in PubMed database, these genes may provide us the new orientation in experimental research and clinical study. Conclusions: Our results may provide more deep insight into the mechanism and a promising therapeutic target. The next step is to put our emphasis on an experiment level and to verify the novel genes from 13 hub genes.


Assuntos
Traumatismos dos Nervos Periféricos , Gânglios Espinais , Ontologia Genética , Humanos , Análise em Microsséries , Nervo Isquiático
9.
Eur Spine J ; 28(5): 1092-1112, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30666481

RESUMO

PURPOSE: It is an open question whether cell transplantation can provide safety and effective outcome to spinal cord injury (SCI) patient which has remained controversial for almost 40 years. This study aimed to evaluate the safety and efficacy of cell transplantation in SCI patients. METHOD: Studies of the cell transplantation for SCI were retrieved from PubMed, Embase, Medline, Cochrane Library and analyzed quantitative data by Review Manager 5.3. RESULTS: Twenty-one clinical controlled studies with 973 patients were included. The pooled results suggested that cell transplantation significantly improved ASIA score, ASIA motor score, ASIA sensory score, Barthel Index score, residual urine volume, rehabilitative time of automatic micturition. Furthermore, subgroup analysis indicated that the stem cells exhibited more potent than the non-stem cells in spinal cord repair. Cell transplantation at more than 14 days after injury showed more significant improvements than that within 14 days from injury. The dosage of cell transplantation between 1-5 × 107 and 10-20 × 107 was the potent quantity for the patient with SCI. Intrathecal injection and intravenous + intrathecal injection showed more superior to the other method. The top 5 adverse events were febrile reaction (11.5%), neurologic pain (11.3%), headache (2.6%), neurologic deterioration (2.4%), and rigidity or spasticity (1.6%). CONCLUSION: Cell transplantation appears to be a safe therapeutic strategy possessing substantial beneficial effects in the patients with SCI in clinic. Moreover, treating SCI with stem cell, the dosage of cells between 1-5 × 107 and 10-20 × 107, in intermediate or chronic phase, minimally invasive techniques, may bring more advantage to SCI patient. These slides can be retrieved under Electronic Supplementary Material.


Assuntos
Transplante de Células , Traumatismos da Medula Espinal/cirurgia , Transplante de Células/efeitos adversos , Transplante de Células/métodos , Transplante de Células/estatística & dados numéricos , Humanos , Complicações Pós-Operatórias
10.
Sci Rep ; 5: 12718, 2015 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-26228734

RESUMO

Photoluminescence (PL) is a nondestructive and powerful method to investigate carrier recombination and transport characteristics in semiconductor materials. In this study, the temperature dependences of photoluminescence of GaAs-AlxGa1-xAs multi-quantum wells samples with and without p-n junction were measured under both resonant and non-resonant excitation modes. An obvious increase of photoluminescence(PL) intensity as the rising of temperature in low temperature range (T < 50 K), is observed only for GaAs-AlxGa1-xAs quantum wells sample with p-n junction under non-resonant excitation. The origin of the anomalous increase of integrated PL intensity proved to be associated with the enhancement of carrier drifting because of the increase of carrier mobility in the temperature range from 15 K to 100 K. For non-resonant excitation, carriers supplied from the barriers will influence the temperature dependence of integrated PL intensity of quantum wells, which makes the traditional methods to acquire photoluminescence characters from the temperature dependence of integrated PL intensity unavailable. For resonant excitation, carriers are generated only in the wells and the temperature dependence of integrated PL intensity is very suitable to analysis the photoluminescence characters of quantum wells.


Assuntos
Luminescência , Teoria Quântica , Medições Luminescentes , Física/métodos , Semicondutores , Temperatura
11.
J Colloid Interface Sci ; 393: 92-6, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23200347

RESUMO

A series of photoelectric conversion films consisting of sandwich-type polyoxometalates [P(2)W(18)M(4)(H(2)O)(2)O(68)](10-) (P(2)W(18)M(4), M=Ni, Cu, Zn) and a bichromophore hemicyanine of (E)-1,1'-(hexane-1,6-diyl)bis(4-(4-(dimethylamino)styryl)pyridinium) bromide (H(6)) were prepared on quartz and indium-tin-oxide (ITO)-coated glass substrates by electrostatic self-assembly. The UV-visible absorption spectroscopy showed that the films were uniformly deposited with the visible absorption bands for H(6) in the films exhibiting different extents of bathochromic shifts with respect to H(6) aqueous solution. The (P(2)W(18)M(4)/H(6))(n) films exhibited cathodic photocurrents as irradiated with white light. The photocurrent action spectra were found to match with the absorption spectra of the films, indicating that the cathodic photocurrents were generated based on intramolecular charge transfer excitation of the H(6) in the films. The photocurrents were found to strongly depend on the transition metal ions M in (P(2)W(18)M(4)/H(6))(n) films. The effects of applied bias voltages, electron acceptor added in the electrolyte, and layer numbers of the films on photocurrent generation of (P(2)W(18)M(4)/H(6))(n) films were also examined, and photoelectric mechanism discussed.


Assuntos
Carbocianinas/química , Corantes/química , Técnicas Eletroquímicas , Compostos de Tungstênio/química , Modelos Moleculares , Estrutura Molecular , Processos Fotoquímicos , Eletricidade Estática , Compostos de Tungstênio/síntese química
12.
BMC Genomics ; 11 Suppl 2: S9, 2010 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-21047390

RESUMO

BACKGROUND: Ultrasound imaging technology has wide applications in cattle reproduction and has been used to monitor individual follicles and determine the patterns of follicular development. However, the speckles in ultrasound images affect the post-processing, such as follicle segmentation and finally affect the measurement of the follicles. In order to reduce the effect of speckles, a bilateral filter is developed in this paper. RESULTS: We develop a new bilateral filter for speckle reduction in ultrasound images for follicle segmentation and measurement. Different from the previous bilateral filters, the proposed bilateral filter uses normalized difference in the computation of the Gaussian intensity difference. We also present the results of follicle segmentation after speckle reduction. Experimental results on both synthetic images and real ultrasound images demonstrate the effectiveness of the proposed filter. CONCLUSIONS: Compared with the previous bilateral filters, the proposed bilateral filter can reduce speckles in both high-intensity regions and low intensity regions in ultrasound images. The segmentation of the follicles in the speckle reduced images by the proposed method has higher performance than the segmentation in the original ultrasound image, and the images filtered by Gaussian filter, the conventional bilateral filter respectively.


Assuntos
Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Folículo Ovariano/diagnóstico por imagem , Animais , Bovinos , Feminino , Ultrassonografia/métodos
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(9): 1862-5, 2007 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-18051548

RESUMO

In the present paper, a new method for indirect determination of Vc by atomic absorption spectrometry is proposed, based on the reducing properties of Ag+. The effects of temperature, reaction time and use level of Ag+ on the experiment were studied. Room-temperature and reaction time of 35 minutes were chosen. The oxidant amount is 2.0 mL solution of Ag+ (1.0 microg mL(-1)). Meanwhile the AAS working conditions for Ag determination were optimized. The proposed method allows the determination of Vc in a wide range with a relative standard deviation of 2.04%, and the detection limit is less than 1 microg x mL(-1). The method cannot be disturbed by the colour of sample. The interference of coexistent substance is also weak. Other methods for determining Vc could be remedied by this method. Two kinds of standard curves were plotted, standard working curve of sliver and standard working curve of Vc. The former is easier, while the latter is more accurate and could be applied flexibly according to the physical circumstances. This method is easy to control and has been applied to the determination of ascorbic acid in pharmaceutical preparations and orange juice. The recovery ratio of this method is 99.30%-106.06%. The results obtained in the analysis agreed well with the iodimetry in pharmacopeia.


Assuntos
Ácido Ascórbico/análise , Espectrofotometria Atômica/métodos , Bebidas/análise
14.
Comput Med Imaging Graph ; 28(8): 461-70, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15541953

RESUMO

This paper presents an approach for reducing speckle in three dimensional (3D) ultrasound images. A 2D speckle reduction technique, speckle reducing anisotropic diffusion (SRAD), is explored and extended to 3D. 3D SRAD is advantageous in that, like 2D SRAD, it keeps the advantages of the conventional anisotropic diffusion and the traditional speckle reducing filter, the Lee filter, by exploiting the instantaneous coefficient of variation (ICOV). Besides, 3D SRAD uses 3D information; thus it overcomes the shortcoming of the 2D technique that only uses 2D information. The algorithm of 3D SRAD is presented in the continuous domain as well as in the discrete domain. Experiments have been performed on both synthetic and real 3D ultrasound images and the experimental results were compared with those obtained by 3D anisotropic diffusion and the 3D Lee filter. The experimental results show that the quality of the 3D SRAD for speckle reduction in 3D ultrasound images improves upon that of 3D anisotropic diffusion and 3D Lee filter in terms of edge preservation and the smoothness of homogenous regions.


Assuntos
Aumento da Imagem/métodos , Ultrassonografia/métodos , Algoritmos , Animais , Anisotropia , Imageamento Tridimensional , Camundongos , Imagens de Fantasmas
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