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1.
Front Oncol ; 13: 1259416, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37841437

RESUMO

Purpose: The objective of this research is to compare the efficacy of conventional and hypofractionated radiotherapy treatment plans for breast cancer patients, with a specific focus on the unique features of the Halcyon system. Methods and materials: The study collected and analyzed dose volume histogram (DVH) data for two groups of treatment plans implemented using the Halcyon system. The first group consisted of 19 patients who received conventional fractionated (CF) treatment with a total dose of 50 Gy in 25 fractions, while the second group comprised 9 patients who received hypofractionated (HF) treatment with a total dose of 42.56 Gy in 16 fractions. The DVH data was used to calculate various parameters, including tumor control probability (TCP), normal tissue complication probability (NTCP), and equivalent uniform dose (EUD), using radiobiological models. Results: The results indicated that the CF plan resulted in higher TCP but lower NTCP for the lungs compared to the HF plan. The EUD for the HF plan was approximately 49 Gy (114% of its total dose) while that for the CF plan was around 53 Gy (107% of its total dose). Conclusions: The analysis suggests that while the CF plan is better at controlling tumors, it is not as effective as the HF plan in minimizing side effects. Additionally, it is suggested that there may be an optimal configuration for the HF plan that can provide the same or higher EUD than the CF plan.

2.
Biomolecules ; 10(9)2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32962160

RESUMO

Donepezil (DPZ) is an acetylcholinesterase inhibitor used for the clinical treatment of mild cognitive impairment. However, DPZ has been reported to have adverse effects, including causing abnormal cardiac rhythm, insomnia, vomiting, and muscle cramps. However, the existence of these effects in subjects without Dementia is unknown. In this study, we use zebrafish to conduct a deeper analysis of the potential adverse effects of DPZ on the short-term memory and behaviors of normal zebrafish by performing multiple behavioral and biochemical assays. Adult zebrafish were exposed to 1 ppm and 2.5 ppm of DPZ. From the results, DPZ caused a slight improvement in the short-term memory of zebrafish and induced significant elevation in aggressiveness, while the novel tank and shoaling tests revealed anxiolytic-like behavior to be caused by DPZ. Furthermore, zebrafish circadian locomotor activity displayed a higher reduction of locomotion and abnormal movement orientation in both low- and high-dose groups, compared to the control group. Biomarker assays revealed that these alterations were associated with an elevation of oxytocin and a reduction of cortisol levels in the brain. Moreover, the significant increases in reactive oxygen species (ROS) and malondialdehyde (MDA) levels in muscle tissue suggest DPZ exposure induced muscle tissue oxidative stress and muscle weakness, which may underlie the locomotor activity impairment. In conclusion, we show, for the first time, that chronic waterborne exposure to DPZ can severely induce adverse effects on normal zebrafish in a dose-dependent manner. These unexpected adverse effects on behavioral alteration should be carefully addressed in future studies considering DPZ conducted on zebrafish or other animals.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Donepezila/toxicidade , Exposição Ambiental/efeitos adversos , Testes de Toxicidade Crônica/métodos , Peixe-Zebra/fisiologia , Animais , Encéfalo/metabolismo , Inibidores da Colinesterase/toxicidade , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Malondialdeído/metabolismo , Memória de Curto Prazo/efeitos dos fármacos , Memória de Curto Prazo/fisiologia , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Músculos/efeitos dos fármacos , Músculos/metabolismo , Músculos/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
3.
Int J Mol Sci ; 21(8)2020 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-32325720

RESUMO

Lysophosphatidic acid (LPA) is a small lysophospholipid molecule that activates multiple cellular functions through pathways with G-protein-coupled receptors. So far, six LPA receptors (LPAR1 to LPAR6) have been discovered and each one of them can connect to the downstream cell message-transmitting network. A previous study demonstrated that LPA receptors found in blood-producing stem cells can enhance erythropoietic processes through the activation of LPAR3. In the current study, newly discovered functions of LPAR3 were identified through extensive behavioral tests in lpar3 knockout (KO) zebrafish. It was found that the adult lpar3 KO zebrafish display an abnormal movement orientation and altered exploratory behavior compared to that of the control group in the three-dimensional locomotor and novel tank tests, respectively. Furthermore, consistent with those results, in the circadian rhythm locomotor activity test, the lpar3 KO zebrafish showed a lower level of angular velocity and average speed during the light cycles, indicating an hyperactivity-like behavior. In addition, the mutant fish also exhibited considerably higher locomotor activity during the dark cycle. Supporting those findings, this phenomenon was also displayed in the lpar3 KO zebrafish larvae. Furthermore, several important behavior alterations were also observed in the adult lpar3 KO fish, including a lower degree of aggression, less interest in conspecific social interaction, and looser shoal formation. However, there was no significant difference regarding the predator avoidance behavior between the mutant and the control fish. In addition, lpar3 KO zebrafish displayed memory deficiency in the passive avoidance test. These in vivo results support for the first time that the lpar3 gene plays a novel role in modulating behaviors of anxiety, aggression, social interaction, circadian rhythm locomotor activity, and memory retention in zebrafish.


Assuntos
Ansiedade/metabolismo , Encéfalo/metabolismo , Ritmo Circadiano/genética , Memória de Curto Prazo , Receptores de Ácidos Lisofosfatídicos/metabolismo , Peixe-Zebra/metabolismo , Agressão , Animais , Animais Geneticamente Modificados , Ansiedade/genética , Aprendizagem da Esquiva , Escala de Avaliação Comportamental , Ritmo Circadiano/efeitos da radiação , Testes de Percepção de Cores , Ensaio de Imunoadsorção Enzimática , Comportamento Exploratório/efeitos da radiação , Regulação da Expressão Gênica/genética , Técnicas de Inativação de Genes , Hormônios/metabolismo , Locomoção/genética , Locomoção/efeitos da radiação , Família Multigênica , Neurotransmissores/metabolismo , Análise de Componente Principal , Receptores de Ácidos Lisofosfatídicos/genética , Peixe-Zebra/genética
4.
Int J Mol Sci ; 21(4)2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32098080

RESUMO

A T-maze test is an experimental approach that is used in congenital research. However, the food reward-based protocol for the T-maze test in fish has low efficiency and a long training period. The aim of this study is to facilitate the T-maze conditions by using a combination of the principles of passive avoidance and a spatial memory test. In our modified T-maze settings, electric shock punishment (1-2 V, 0.3-0.5 mA) is given at the left arm, with a green cue at the right arm. Also, the depth of both arms of the T-maze was increased. The parameters measured in our T-maze design were latency, freezing time, and time spent in different areas of the T-maze. We validated the utility of our modified T-maze protocol by showing the consistent finding of memory impairment in ZnCl2-treated fish, which has been previously detected with the passive avoidance test. In addition, we also tested the spatial memory performance of leptin a (lepa) mutants which displayed an obesity phenotype. The results showed that although the learning and memory performance for lepa KO fish were similar to control fish, they displayed a higher freezing behavior during the training phase. In conclusion, we have established a modified T-maze protocol that can be used to evaluate the anxiety, learning, and memory capacity of adult zebrafish within three days, for the first time.


Assuntos
Aprendizagem em Labirinto/fisiologia , Memória/fisiologia , Peixe-Zebra/fisiologia , Animais
5.
RSC Adv ; 9(46): 26588-26597, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35528575

RESUMO

4-Nitrophenol (4-NP) is a promulgated priority pollutant, which can cause a negative impact on human health. The development of a direct and effective technique for the rapid detection and screening of 4-NP is, therefore, of urgent need. In this study, the blue luminescent sulfur-doped graphene quantum dots (S-GQDs) with a size of 1-5 nm are fabricated using a one-step pyrolysis procedure in the presence of citric acid and 3-mercaptosuccinic acid. The S-GQDs exhibit a strong emission band at 450 nm under the excitation of 330 nm UV light. 4-NP can serve as the fluorescence quencher by the π-π interaction with S-GQD, resulting in the linear decrease in fluorescence intensity after the addition of various 4-NP concentrations ranging from 10 nM to 200 µM. The S-GQDs serve as the sensing probe to enhance the analytical performance on 4-NP detection with the limit of detection values of 0.7 and 3.5 nM in deionized water and wastewater, respectively. The S-GQD based sensing platform can be used to detect 4-NP in different matrices of water and wastewater. In addition, the detected percentages of spiked 4-NP concentrations in the presence of different matrices and interferences are in the range of (98 ± 5)-(108 ± 2)%. Moreover, the S-GQD based paper sensor can rapidly screen 4-NP in wastewater within 1 min. Results obtained in this study clearly demonstrate the superiority of S-GQDs as a promising fluorescence probe for highly sensitive and selective detection of a wide concentration range of 4-NP in deionized water and wastewater.

6.
Biomed Res Int ; 2016: 9302428, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26881233

RESUMO

A study of 600 rural under-five mothers' knowledge, attitude, and practice (KAP) in child care was performed in 4 southern provinces of Vietnam. The mothers were randomly selected and interviewed about sociodemographic factors, health seeking behaviour, and practice of home care of children and neonates. 93.2% of the mothers were literate and well-educated, which has been shown to be important for child health care. 98.5% were married suggesting a stable family, which is also of importance for child health. Only 17.3% had more than 2 children in their family. The mother was the main caretaker in 77.7% of the families. Only 1% would use quacks as their first health contact, but 25.2% would use a private clinic, which therefore eases the burden on the government system. Nearly 69% had given birth in a hospital, 27% in a commune health station, and only 2.7% at home without qualified assistance. 89% were giving exclusive breast feeding at 6 months, much more frequent than in the cities. The majority of the mothers could follow IMCI guideline for home care, although 25.2% did not deal correctly with cough and 38.7% did not deal correctly with diarrhoea. Standard information about Integrated Management of Childhood Illnesses (IMCI) based home care is still needed.


Assuntos
Cuidado da Criança , Conhecimentos, Atitudes e Prática em Saúde , Mães , Adulto , Idoso , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , População Rural , Vietnã
7.
Comput Math Methods Med ; 2014: 761536, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24719648

RESUMO

Unsupervised mining of electrocardiography (ECG) time series is a crucial task in biomedical applications. To have efficiency of the clustering results, the prominent features extracted from preprocessing analysis on multiple ECG time series need to be investigated. In this paper, a Harmonic Linear Dynamical System is applied to discover vital prominent features via mining the evolving hidden dynamics and correlations in ECG time series. The discovery of the comprehensible and interpretable features of the proposed feature extraction methodology effectively represents the accuracy and the reliability of clustering results. Particularly, the empirical evaluation results of the proposed method demonstrate the improved performance of clustering compared to the previous main stream feature extraction approaches for ECG time series clustering tasks. Furthermore, the experimental results on real-world datasets show scalability with linear computation time to the duration of the time series.


Assuntos
Eletrocardiografia/métodos , Processamento de Sinais Assistido por Computador , Algoritmos , Arritmias Cardíacas/fisiopatologia , Análise por Conglomerados , Análise de Fourier , Humanos , Modelos Lineares , Análise de Componente Principal , Análise de Regressão , Fatores de Tempo
8.
PLoS One ; 4(12): e8341, 2009 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-20020056

RESUMO

MODS is a novel liquid culture based technique that has been shown to be effective and rapid for early diagnosis of tuberculosis (TB). We evaluated the MODS assay for diagnosis of TB in children in Viet Nam. 217 consecutive samples including sputum (n = 132), gastric fluid (n = 50), CSF (n = 32) and pleural fluid (n = 3) collected from 96 children with suspected TB, were tested by smear, MODS and MGIT. When test results were aggregated by patient, the sensitivity and specificity of smear, MGIT and MODS against "clinical diagnosis" (confirmed and probable groups) as the gold standard were 28.2% and 100%, 42.3% and 100%, 39.7% and 94.4%, respectively. The sensitivity of MGIT and MODS was not significantly different in this analysis (P = 0.5), but MGIT was more sensitive than MODS when analysed on the sample level using a marginal model (P = 0.03). The median time to detection of MODS and MGIT were 8 days and 13 days, respectively, and the time to detection was significantly shorter for MODS in samples where both tests were positive (P<0.001). An analysis of time-dependent sensitivity showed that the detection rates were significantly higher for MODS than for MGIT by day 7 or day 14 (P<0.001 and P = 0.04), respectively. MODS is a rapid and sensitive alternative method for the isolation of M.tuberculosis from children.


Assuntos
Testes Diagnósticos de Rotina/métodos , Diagnóstico Precoce , Tuberculose Pulmonar/diagnóstico , Adolescente , Técnicas de Tipagem Bacteriana , Criança , Pré-Escolar , Demografia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/isolamento & purificação , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo , Resultado do Tratamento , Tuberculose Pulmonar/líquido cefalorraquidiano , Tuberculose Pulmonar/terapia
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