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1.
PLoS One ; 18(12): e0294080, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38060542

RESUMO

The X-ray energy spectrum is crucial for image quality and dosage assessment in mammography, radiography, fluoroscopy, and CT which are frequently used for the diagnosis of many diseases including but not limited to patients with cardiovascular and cerebrovascular diseases. X-ray tubes have an electron filament (cathode), a tungsten/rubidium target (anode) oriented at an angle, and a metal filter (aluminum, beryllium, etc.) that may be placed in front of an exit window. When cathode electrons meet the anode, they generate X-rays with varied energies, creating a spectrum from zero to the electrons' greatest energy. In general, the energy spectrum of X-rays depends on the electron beam's energy (tube voltage), target angle, material, filter thickness, etc. Thus, each imaging system's X-ray energy spectrum is unique to its tubes. The primary goal of the current study is to develop a clever method for quickly estimating the X-ray energy spectrum for a variety of tube voltages, filter materials, and filter thickness using a small number of unique spectra. In this investigation, two distinct filters made of beryllium and aluminum with thicknesses of 0.4, 0.8, 1.2, 1.6, and 2 mm were employed to obtain certain limited X-ray spectra for tube voltages of 20, 30, 40, 50, 60, 80, 100, 130, and 150 kV. The three inputs of 150 Multilayer Perceptron (MLP) neural networks were tube voltage, filter type, and filter thickness to forecast the X-ray spectra point by point. After training, the MLP neural networks could predict the X-ray spectra for tubes with voltages between 20 and 150 kV and two distinct filters made of aluminum and beryllium with thicknesses between 0 and 2 mm. The presented methodology can be used as a suitable, fast, accurate and reliable alternative method for predicting X-ray spectrum in medical applications. Although a technique was put out in this work for a particular system that was the subject of Monte Carlo simulations, it may be applied to any genuine system.


Assuntos
Alumínio , Berílio , Humanos , Raios X , Radiografia , Redes Neurais de Computação , Método de Monte Carlo
2.
Arch Biochem Biophys ; 749: 109790, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37858664

RESUMO

Skin wound healing is a dynamic and complex process that involves multiple physiological and cellular events. Grape seed proanthocyanidins (GSP) have strong anti-oxidation and elimination of oxygen free radicals, and have been shown to significantly promote wound healing, but the underlying mechanism remains unclear. Studies have indicated that reactive oxygen species (ROS) acts as an upstream signal to induce mitophagy, suggesting that GSP can regulate mitophagy through the signal pathway. This study aimed to investigate whether GSP regulates mitophagy by down-regulating oxidative stress to promote wound healing. In vivo, GSP treatment accelerated wound healing, granulation tissue formation, collagen deposition, and angiogenesis in mice. Moreover, GSP down-regulated ROS levels and promoted the expression of antioxidant proteins by up-regulating the expression of p-JNK/FOXO3a protein, thereby regulating the expression of mitophagy-related proteins. In vitro, 4 µg/mL GSP showed no apparent toxic effects on cells and effectively reduce the oxidative stress damage of cells induced by H2O2. Western blot and superoxide anion fluorescence probe further confirmed that GSP effectively reduced Dihydroethidium content and up-regulated the expression of antioxidant proteins by activation of p-JNK/FOXO3a protein expression, thereby regulating mitophagy. Taken together, the findings from in vitro and in vivo experiments provide new insights into the promotion of wound healing by GSP.


Assuntos
Antioxidantes , Proantocianidinas , Camundongos , Animais , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células Endoteliais/metabolismo , Peróxido de Hidrogênio/farmacologia , Mitofagia , Proantocianidinas/farmacologia , Transdução de Sinais , Cicatrização
3.
BMC Med Educ ; 23(1): 530, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37491283

RESUMO

BACKGROUND: The traditional Chinese dentistry classroom teaching model focuses on the instruction of knowledge details, but less on the frameworks and learners' motivation. Here, we introduced a combination of mind mapping and PBL instruction (MBL)into the prosthodontics course for Chinese dental students. This study aimed to evaluate the effectiveness and efficiency of MBL in prosthodontics and make observations from the students' perspectives, based on their response with the learning process. METHODS: We prospectively enrolled 56 fourth-year undergraduates of stomatology, and these participants were randomly allocated into either the combined mind map teaching group (MBL) or the problem-based learning group (PBL) to attend the prosthodontics course. An anonymous questionnaire was also administered to both groups to evaluate the students' perceptions and experiences, using closed and open-ended items. Data were analyzed using descriptive statistics and thematic analysis. RESULTS: The students' responses to closed items indicate their experience in PBL and MBL to be positive, including increased motivation, improved memory of knowledge, enhanced discipline connection and raised teamwork, with fairly higher ratings for the MBL group. However, the tutor-guided competence scores including the memory and framework part, were significantly higher for MBL group than PBL group (two-way ANOVA, p < 0.01, p < 0.001, respectively). Meanwhile, the self-perceived competence scores including the motivation, framework and teamwork part, were significantly higher for MBL group than PBL group (two-way ANOVA, p < 0.01, p < 0.001, p < 0.05, respectively). CONCLUSION: Our findings suggest that MBL teaching approach can help in integration of knowledge structure and enhance clinical reasoning. MBL is an effective and well-organized method in prosthodontics course for dental students.


Assuntos
Aprendizagem Baseada em Problemas , Prostodontia , Estudantes de Odontologia , Humanos , População do Leste Asiático , Aprendizagem , Aprendizagem Baseada em Problemas/métodos , Prostodontia/educação , Inquéritos e Questionários , China , Modelos Educacionais
4.
J Coll Physicians Surg Pak ; 28(2): 110-114, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29394968

RESUMO

OBJECTIVE: To assess the sensitivity of the Alvarado score (AS), modified Alvarado score (MAS), Fenyo-Lindberg score (FS), Lintula score (LS), Eskelinen score (ES), Teicher score (TS), and Christian score (CS) [seven scorings] in patients with acute appendicitis (AA). STUDY DESIGN: Analytical study. PLACE AND DURATION OF STUDY: The First Affiliated Hospital of Chongqing Medical University, China, from January 2012 to June 2015. METHODOLOGY: Patients with diagnosis of AA were evaluated retrospectively to compare the scoring systems. The diagnostic sensitivity (the correct number of diagnoses divided by the total number) was compared. Data were analyzed using SPSS software. RESULTS: One hundred and seventy-nine patients were studied. The sensitivity of AS was 92.7%; It outperformed each of the other scores. The sensitivity of FS, LS, and TS in women was lower than that in men (p=0.016, p<0.001, and p<0.001, respectively). The sensitivity of the FS, ES, TS, and CS in patients with a duration of illness greater than 48 hours was lower than that in patients with a duration of illness less than 48 hours (p<0.001 for all). CONCLUSION: AS is the most useful and sensitive diagnostic tool for AA. FS, LS, and TS had a lower diagnostic sensitivity in women; and FS, ES, TS, and CS had a low sensitivity in patients with a duration of illness greater than 48 hours.


Assuntos
Apendicite/diagnóstico , Medição da Dor , Doença Aguda , Adolescente , Adulto , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Vômito/etiologia , Adulto Jovem
5.
Genome Res ; 21(10): 1601-15, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21890681

RESUMO

Emerging evidence suggests that poor glycemic control mediates post-translational modifications to the H3 histone tail. We are only beginning to understand the dynamic role of some of the diverse epigenetic changes mediated by hyperglycemia at single loci, yet elevated glucose levels are thought to regulate genome-wide changes, and this still remains poorly understood. In this article we describe genome-wide histone H3K9/K14 hyperacetylation and DNA methylation maps conferred by hyperglycemia in primary human vascular cells. Chromatin immunoprecipitation (ChIP) as well as CpG methylation (CpG) assays, followed by massive parallel sequencing (ChIP-seq and CpG-seq) identified unique hyperacetylation and CpG methylation signatures with proximal and distal patterns of regionalization associative with gene expression. Ingenuity knowledge-based pathway and gene ontology analyses indicate that hyperglycemia significantly affects human vascular chromatin with the transcriptional up-regulation of genes involved in metabolic and cardiovascular disease. We have generated the first installment of a reference collection of hyperglycemia-induced chromatin modifications using robust and reproducible platforms that allow parallel sequencing-by-synthesis of immunopurified content. We uncover that hyperglycemia-mediated induction of genes and pathways associated with endothelial dysfunction occur through modulation of acetylated H3K9/K14 inversely correlated with methyl-CpG content.


Assuntos
Aorta/citologia , Células Endoteliais/metabolismo , Epigênese Genética , Hiperglicemia/genética , Acetilação , Acetiltransferases/metabolismo , Células Cultivadas , Cromossomos Humanos , Ilhas de CpG , Metilação de DNA , Diabetes Mellitus/genética , Angiopatias Diabéticas/genética , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Histonas/metabolismo , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Cultura Primária de Células , Análise de Sequência de DNA , Transcrição Gênica
6.
Am J Med Sci ; 339(1): 22-4, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20057274

RESUMO

Buckwheat is an important crop in China and is also known as an important potent allergen in the population. Here, we report a series of 7 Chinese patients with buckwheat allergy, which has never been reported previously in China. Mean age was 20 years at diagnosis. Patients' symptoms were respiratory, gastrointestinal, cutaneous, and anaphylactic. The routes of exposure were varied. Laboratory allergy test showed that buckwheat-specific IgE levels in all patients were remarkably elevated. Allergen avoidance was the best treatment in these cases. The data suggest that buckwheat can induce various clinical manifestations. Anaphylaxis might be characterized by severe symptoms. Buckwheat pillow is an important source of exposure to buckwheat in China and other Asian countries. Therefore, public education with effective avoidance measures should be an integral part of the management strategy.


Assuntos
Povo Asiático , Fagopyrum/efeitos adversos , Hipersensibilidade Alimentar/diagnóstico , Adolescente , Corticosteroides/uso terapêutico , Adulto , Roupas de Cama, Mesa e Banho/efeitos adversos , Criança , Pré-Escolar , Feminino , Seguimentos , Hipersensibilidade Alimentar/sangue , Hipersensibilidade Alimentar/tratamento farmacológico , Humanos , Imunoglobulina E/sangue , Masculino
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