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1.
IEEE Trans Neural Netw Learn Syst ; 34(4): 2105-2118, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-34487498

RESUMO

A single dendritic neuron model (DNM) that owns the nonlinear information processing ability of dendrites has been widely used for classification and prediction. Complex-valued neural networks that consist of a number of multiple/deep-layer McCulloch-Pitts neurons have achieved great successes so far since neural computing was utilized for signal processing. Yet no complex value representations appear in single neuron architectures. In this article, we first extend DNM from a real-value domain to a complex-valued one. Performance of complex-valued DNM (CDNM) is evaluated through a complex XOR problem, a non-minimum phase equalization problem, and a real-world wind prediction task. Also, a comparative analysis on a set of elementary transcendental functions as an activation function is implemented and preparatory experiments are carried out for determining hyperparameters. The experimental results indicate that the proposed CDNM significantly outperforms real-valued DNM, complex-valued multi-layer perceptron, and other complex-valued neuron models.


Assuntos
Redes Neurais de Computação , Neurônios , Processamento de Sinais Assistido por Computador , Algoritmos
2.
J Clin Biochem Nutr ; 64(1): 91-95, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30705518

RESUMO

Plasma ghrelin level is influenced by Helicobacter pylori (H. pylori) status and the severity of gastric mucosal atrophy, and the ghrelin level is associated with nutrition status in hemodialysis patients. Here, we investigated the efficacy of H. pylori eradication therapy in improving nutrition status in relation to the ghrelin level in H. pylori-positive hemodialysis patients. Of H. pylori-positive patients receiving hemodialysis at 8 dialysis center, 21 patients underwent gastroduodenoscopy for evaluation of the severity of gastric atrophy, and nutrition markers and plasma ghrelin levels before and 1 year after H. pylori eradication therapy were evaluated. Serum cholinesterase level was significantly increased after H. pylori eradication compared with the level before eradication (303.2 ± 76.0 vs 287.3 ± 68.1 IU/L, p = 0.029). In particular, cholesterol (before, 196.6 ± 23.2 mg/dl; after, 206.1 ± 25.9 mg/dl, p = 0.042) and cholinesterase levels (before, 296.9 ± 70.8 IU/L; after, 316.4 ± 73.8 IU/L, p = 0.049) increased more strongly in patients with mild-moderate atrophy than those with severe atrophy, irrespective of improvement of plasma acyl-ghrelin and desacyl-ghrelin levels after eradication therapy. In conclusion, H. pylori eradication may improve nutrition status by increasing serum cholinesterase and cholesterol levels in hemodialysis patients, especially those with mild and moderate gastric mucosal atrophy.

3.
Bioorg Med Chem ; 25(21): 6007-6015, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28986114

RESUMO

6-O-(2-Nitrobenzyl)guanosine and 4-O-(2-nitrobenzyl)uridine triphosphates (NBGTP, NBUTP) were synthesized, and their biochemical and photophysical properties were evaluated. We synthesized NBUTP using the canonical triphosphate synthesis method and NBGTP from 2',3'-O-TBDMS guanosine via a triphosphate synthesis method by utilizing mild acidic desilylation conditions. Deprotection of the nitrobenzyl group in NBGTP and NBUTP proceeded within 60s by UV irradiation at 365nm. Experiments using NBGTP or NBUTP in T7-RNA transcription reactions showed that NBGTP could be useful for the photocontrol of transcription by UV irradiation.


Assuntos
RNA Polimerases Dirigidas por DNA/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Guanosina/farmacologia , Transcrição Gênica/efeitos dos fármacos , Raios Ultravioleta , Uridina Trifosfato/farmacologia , Proteínas Virais/antagonistas & inibidores , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Guanosina/análogos & derivados , Guanosina/síntese química , Estrutura Molecular , Relação Estrutura-Atividade , Transcrição Gênica/genética , Uridina Trifosfato/síntese química , Uridina Trifosfato/química , Proteínas Virais/genética , Proteínas Virais/metabolismo
4.
Contrib Nephrol ; 186: 71-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26283562

RESUMO

In Japan, use of a surgically superficialized brachial artery is recommended for vascular access in patients who are either unable to tolerate hemodialysis because of reduced cardiac function or who do not have vessels suitable for creation of an arteriovenous fistula. Superficializing a brachial artery involves relocating a portion of the artery into subcutaneous tissue and immobilizing the artery at that location. Superficialized artery access can result in certain serious complications, such as an aneurysm and/or stenosis. In order to avoid such complications, we attempted applying the buttonhole method to this vascular access. A buttonhole track was created slightly distal from the center of the superficialized portion of a brachial artery approximately 2 weeks after superficialization. When arteriosclerosis was evident in that location, we tried to find a less sclerotic portion, under ultrasonography guidance, for creation of the arterial-side buttonhole track. For returning extracorporeal circulated blood, a normal vein on the arm with a superficialized brachial artery was cannulated with a sharp needle. Recently, however, we attempted to create a buttonhole track also on a vein for venous-side buttonhole cannulation. The brachial artery was superficialized in 5 patients. In all patients, buttonhole cannulation was successfully performed with the artery access. Buttonhole cannulation had been performed on these patients for 8-54 months. No serious complications such as a pseudoaneurysm were found in these patients. Serious complications specific to the superficialized artery access may be prevented by application of the buttonhole method.


Assuntos
Artéria Braquial/cirurgia , Cateterismo Periférico/métodos , Falência Renal Crônica/terapia , Diálise Renal/métodos , Humanos , Punções/métodos
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