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1.
Artículo en Chino | WPRIM | ID: wpr-982248

RESUMEN

The proton treatment control system is the supporting software of the proton therapy device, which specifically coordinates and controls the status and work of each subsystem. In this study, the software architecture and hardware implementation of the proton treatment control system was developed and built a foundation for the overall debugging. Using C# programming language and WPF programming techniques, TCP network communication protocol specified by the proton treatment technical document and MVVM pattern in Windows system, the logic design and implementation of each level were studied. Meanwhile, the communication interface between the subsystems under TCP communication protocol was agreed. The logic design and research of the setup field and treatment field were carried out. And the User Interface was designed and developed using the above technology. The program realizes the communication and interaction between the proton treatment control system and each subsystem, so as to control and monitor the whole treatment process. The proton treatment control system provides a software basis for the remote overall debugging and on-line monitor and control of proton treatment device.


Asunto(s)
Protones , Interfaz Usuario-Computador , Programas Informáticos , Computadores , Lógica
2.
Neuroscience Bulletin ; (6): 845-862, 2023.
Artículo en Inglés | WPRIM | ID: wpr-982425

RESUMEN

Adenosine triphosphate (ATP) is well-known as a universal source of energy in living cells. Less known is that this molecule has a variety of important signaling functions: it activates a variety of specific metabotropic (P2Y) and ionotropic (P2X) receptors in neuronal and non-neuronal cell membranes. So, a wide variety of signaling functions well fits the ubiquitous presence of ATP in the tissues. Even more ubiquitous are protons. Apart from the unspecific interaction of protons with any protein, many physiological processes are affected by protons acting on specific ionotropic receptors-acid-sensing ion channels (ASICs). Both protons (acidification) and ATP are locally elevated in various pathological states. Using these fundamentally important molecules as agonists, ASICs and P2X receptors signal a variety of major brain pathologies. Here we briefly outline the physiological roles of ASICs and P2X receptors, focusing on the brain pathologies involving these receptors.


Asunto(s)
Humanos , Canales Iónicos Sensibles al Ácido , Protones , Neuronas , Encefalopatías , Adenosina Trifosfato/fisiología
3.
Neuroscience Bulletin ; (6): 1157-1172, 2023.
Artículo en Inglés | WPRIM | ID: wpr-982467

RESUMEN

Hv1 is the only voltage-gated proton-selective channel in mammalian cells. It contains a conserved voltage-sensor domain, shared by a large class of voltage-gated ion channels, but lacks a pore domain. Its primary role is to extrude protons from the cytoplasm upon pH reduction and membrane depolarization. The best-known function of Hv1 is the regulation of cytosolic pH and the nicotinamide adenine dinucleotide phosphate oxidase-dependent production of reactive oxygen species. Accumulating evidence indicates that Hv1 is expressed in nervous systems, in addition to immune cells and others. Here, we summarize the molecular properties, distribution, and physiological functions of Hv1 in the peripheral and central nervous systems. We describe the recently discovered functions of Hv1 in various neurological diseases, including brain or spinal cord injury, ischemic stroke, demyelinating diseases, and pain. We also summarize the current advances in the discovery and application of Hv1-targeted small molecules in neurological diseases. Finally, we discuss the current limitations of our understanding of Hv1 and suggest future research directions.


Asunto(s)
Animales , Protones , Canales Iónicos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Encéfalo/metabolismo , NADPH Oxidasas , Mamíferos/metabolismo
4.
Artículo en Chino | WPRIM | ID: wpr-1008838

RESUMEN

A quantitative proton nuclear magnetic resonance(qHNMR) method was established to determine the glucose content in commercially available Massa Medicata Fermentata(MMF) products and explore the variations of glucose content in MMF products during processing. The qHNMR spectrum of MMF in deuterium oxide was obtained with 2,2,3,3-d_4-3-(trimethylsilyl) propionate sodium salt as the internal standard substance. With the doublet peaks of terminal hydrogen of glucose with chemical shift at δ 4.65 and δ 5.24 as quantitative peaks, the content of glucose in MMF samples was determined. The glucose content showed a good linear relationship within the range of 0.10-6.44 mg·mL~(-1). The relative standard deviations(RSDs) of precision, stability, repeatability, and recovery for determination were all less than 2.3%. The glucose content varied in different commercially available MMF samples, which were associated with the different fermentation days, wheat bran-to-flour ratios, and processing methods. The glucose content in MMF first increased and then decreased over the fermentation time. Compared with the MMF products fermented with wheat bran or flour alone, the products fermented with both wheat bran and flour had increased glucose. The glucose content of bran-fried MMF was slightly lower than that of raw MMF, while the glucose content in charred MMF was extremely low. In conclusion, the qHNMR method established in this study is simple, fast, and accurate, serving as a new method for determining the glucose content in MMF. Furthermore, this study clarifies the variations of glucose content in MMF during processing, which can not only indicate the processing degree but also provide a scientific basis for revealing the fermentation mechanism and improving the quality control of MMF.


Asunto(s)
Protones , Medicamentos Herbarios Chinos/química , Fibras de la Dieta , Espectroscopía de Resonancia Magnética
5.
Prensa méd. argent ; Prensa méd. argent;106(3): 186-190, 20200000. graf, tab
Artículo en Inglés | LILACS, BINACIS | ID: biblio-1369103

RESUMEN

In this research, the electronic stopping power was calculated using Bethe and Bragg rule equations for the protons in Human tissues (Bone, Muscle (skeletal) and Adipose tissue) all within energy range (0.01-1000) MeV. The equations were programmed using MATLAB 2017, the calculations were compared with the experimental data of the SRIM2013program and PSTAR code, this comparison showed a good agreement with experimental data


Asunto(s)
Humanos , Protones , Radiación Ionizante , Tiempo , Potencia , Análisis de Clases Latentes
6.
Artículo en Chino | WPRIM | ID: wpr-942724

RESUMEN

As a new type of magnetic resonance imaging method, amide proton transfer (APT) imaging can detect the chemical exchange characteristics of free proprotein, peptide amide proton and water proton by water signal changes, reflecting the changes of protein and pH in tissues. In recent years, clinical research on brain tumors, multiple sclerosis, hepatic encephalopathy and cervical cancer have been carried out. It is a radiation-free and non-invasive new magnetic resonance molecular imaging technology. This study briefly reviews the principle of APT technology and its clinical application, and prospects its application prospects in children's abdominal tumors.


Asunto(s)
Niño , Humanos , Abdomen/patología , Amidas , Imagen por Resonancia Magnética , Neoplasias/diagnóstico por imagen , Protones
7.
Artículo en Chino | WPRIM | ID: wpr-880394

RESUMEN

Compared with conventional high energy X-ray radiotherapy, proton/carbon ion has obvious advantages because of its Bragg peak dose distribution. However, proton heavy ion facility has complex structure, high energy and various radiation types due to various nuclear reaction processes, the radiation protection safety brought by the operation of facilities has gradually attracted attention. Taking the proton/carbon ion radiotherapy facility of Shanghai Proton and Heavy Ion Center as an example, the author mainly analyzed the operation principle of proton/carbon ion treatment facility, the basis of radiation protection, analysis of key radiation source points, etc., so as to provide theoretical support and experience for radiation protection.


Asunto(s)
China , Radioterapia de Iones Pesados , Iones Pesados , Exposición Profesional/prevención & control , Protones , Protección Radiológica , Radioterapia
8.
Asia Pacific Allergy ; (4): e30-2019.
Artículo en Inglés | WPRIM | ID: wpr-762879

RESUMEN

Proton pump inhibitors (PPIs) are widely used for the treatment of gastrointestinal diseases. Incidence of drug hypersensitivity reactions (DHRs) to PPIs has been rising, presumably because of their increased consumption. Most DHR are IgE-mediated, with half of the reactions being anaphylactic. We describe the case of a Caucasian 50-year-old female patient referred to our allergy department after 2 episodes of anaphylaxis. The allergy work-up distinguished PPI as a cause of delayed onset (14 hours) and immediate onset (45 minutes) IgE-mediated DHR.


Asunto(s)
Femenino , Humanos , Persona de Mediana Edad , Anafilaxia , Hipersensibilidad a las Drogas , Enfermedades Gastrointestinales , Hipersensibilidad , Incidencia , Inhibidores de la Bomba de Protones , Bombas de Protones , Protones , Pruebas Cutáneas
9.
Artículo en Inglés | WPRIM | ID: wpr-764167

RESUMEN

In this study, we report arterial spin labelling perfusion, proton MR spectroscopy and susceptibility-weighted MR findings of acute necrotizing encephalopathy in a child with rotavirus infection.


Asunto(s)
Niño , Humanos , Encefalopatías , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Perfusión , Protones , Infecciones por Rotavirus
10.
Artículo en Inglés | WPRIM | ID: wpr-764168

RESUMEN

Hyperglycemia-induced hemichorea (HGHC) is a rare but characteristic hyperkinetic movement disorder involving limbs on one side of the body. In a 75-year-old woman with a left-sided HGHC, conventional brain MR imaging showed very subtle T1-hyperintensity and unique gadolinium enhancement in the basal ganglia contralateral to movements. Multi-parametric MRI was acquired using pulse sequence with quantification of relaxation times and proton density by multi-echo acquisition. Myelin map was reconstructed based on new tissue classification modeling. In this case report of multi-parametric MRI, quantitative measurement of myelin change related to HGHC in brain structures and its possible explanations are presented. This is the first study to demonstrate myelin loss related to hyperglycemic insult in multi-parametric quantitative MR imaging.


Asunto(s)
Anciano , Femenino , Humanos , Ganglios Basales , Encéfalo , Clasificación , Extremidades , Gadolinio , Hiperglucemia , Hipercinesia , Imagen por Resonancia Magnética , Trastornos del Movimiento , Vaina de Mielina , Protones , Relajación
11.
Artículo en Inglés | WPRIM | ID: wpr-764180

RESUMEN

PURPOSE: To assess the feasibility of the use of spin-echo echo-planar imaging (SE-EPI) magnetic resonance elastography (MRE) in livers of children and young adults. MATERIALS AND METHODS: Patients (≤ 20 years old) who underwent 3T SE-EPI MRE were included retrospectively. Subjects were divided into three groups according to the purpose of the liver MRI: suspicion of fatty liver or focal fat deposition in the liver (FAT group), liver fibrosis after receiving a Kasai operation from biliary atresia (BA group), and hepatic iron deposition after receiving chemotherapy or transfusions (IRON group). Technical failure of MRE was defined when a stiffness map showed no pixel value with a confidence index higher than 95%, and the patients were divided as success and failure groups accordingly. Clinical findings including age, gender, weight, height, and body mass index and magnetic resonance imaging results including proton density fat fraction (PDFF), T2*, and MRE values were assessed. Factors affecting failure of MRE were evaluated and the image quality in wave propagation image and stiffness map was evaluated using the appropriate scores. RESULTS: Among total 240 patients (median 15 years, 211 patients in the FAT, 21 patients in the BA, and 8 patients in the IRON groups), technical failure was noted in six patients in the IRON group (6/8 patients, 75%), while there were no failures noted in the FAT and BA groups. These six patients had T2* values ranging from 0.9 to 3.8 ms. The image quality scores were not significantly different between the FAT and BA groups (P > 0.999), while the scores were significantly lower in the IRON group (P < 0.001). CONCLUSION: The 3T SE-EPI MRE in children and young adults had a high technical success rate. The technical failure was occurred in children with decreased T2* value (≤ 3.8 ms) from iron deposition.


Asunto(s)
Niño , Humanos , Adulto Joven , Atresia Biliar , Índice de Masa Corporal , Quimioterapia , Imagen Eco-Planar , Diagnóstico por Imagen de Elasticidad , Hígado Graso , Hierro , Cirrosis Hepática , Hígado , Imagen por Resonancia Magnética , Protones , Estudios Retrospectivos
12.
Artículo en Inglés | WPRIM | ID: wpr-760891

RESUMEN

PURPOSE: On the basis of evidence, we aimed to reevaluate the necessity of the empirical proton pump inhibitor (PPI) trial for children with suspected gastroesophageal reflux disease (GERD). METHODS: We analyzed the frequency of GERD in 85 school-age children with gastroesophageal reflux (GER) symptoms, who received 24-hour esophageal pH monitoring and/or upper endoscopy. According to the reflux index (RI), the children were classified into normal (RI <5%), intermediate (5%≤ RI <10%), or abnormal (RI ≥10%) groups. RESULTS: Fifty six were female and 29 were male. Their mean age was 12.6±0.5 (±standard deviation) years (range: 6.8–18.6). The RI analysis showed that the normal group included 76 patients (89.4%), the intermediate group included 6 patients (7.1%), and the abnormal group included 3 patients (3.5%). The DeMeester score was 5.93±4.65, 14.68±7.86 and 40.37±12.96 for the normal, intermediate and abnormal group, respectively (p=0.001). The longest reflux time was 5.56±6.00 minutes, 9.53±7.84 minutes, and 19.46±8.35 minutes in the normal, intermediate, and abnormal group, respectively (p=0.031). Endoscopic findings showed reflux esophagitis in 7 patients. On the basis of the Los Angeles Classification of Esophagitis, 5 of these patients were included in group A, 1 patient, in group B and 1 patient, in group C. CONCLUSION: The incidence of GERD was very low in school-age children with GER symptoms. Therefore, injudicious diagnostic PPI trials would be postponed until the actual prevalence of GERD is verified in future prospective studies.


Asunto(s)
Niño , Femenino , Humanos , Masculino , Clasificación , Endoscopía , Monitorización del pH Esofágico , Esofagitis , Esofagitis Péptica , Reflujo Gastroesofágico , Incidencia , Prevalencia , Estudios Prospectivos , Inhibidores de la Bomba de Protones , Bombas de Protones , Protones
13.
Artículo en Inglés | WPRIM | ID: wpr-760892

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in children. The global prevalence of pediatric NAFLD from general populations is 7.6%. In obese children, the prevalence is higher in Asia. NAFLD has a strong heritable component based on ethnic difference in the prevalence and clustering within families. Genetic polymorphisms of patatin-like phospholipase domain–containing protein 3 (PNPLA3), transmembrane 6 superfamily member 2, and glucokinase regulatory protein (GCKR) are associated with the risk of NAFLD in children. Variants of PNPLA3 and GCKR are more common in Asians. Alterations of the gut microbiome might contribute to the pathogenesis of NAFLD. High fructose intake increases the risk of NAFLD. Liver fibrosis is a poor prognostic factor for disease progression to cirrhosis. Magnetic resonance spectroscopy and magnetic resonance proton density fat fraction are more accurate for steatosis quantification than ultrasound. Noninvasive imaging methods to assess liver fibrosis, such as transient elastography, shear-wave elastography, and magnetic resonance elastography are useful in predicting advanced fibrosis, but they need further validation. Longitudinal follow-up studies into adulthood are needed to better understand the natural history of pediatric NAFLD.


Asunto(s)
Niño , Humanos , Asia , Pueblo Asiatico , Diagnóstico , Progresión de la Enfermedad , Diagnóstico por Imagen de Elasticidad , Epidemiología , Fibrosis , Estudios de Seguimiento , Fructosa , Microbioma Gastrointestinal , Genética , Glucoquinasa , Cirrosis Hepática , Hepatopatías , Espectroscopía de Resonancia Magnética , Microbiota , Historia Natural , Enfermedad del Hígado Graso no Alcohólico , Fosfolipasas , Polimorfismo Genético , Prevalencia , Protones , Ultrasonografía
14.
Artículo en Inglés | WPRIM | ID: wpr-761798

RESUMEN

Sperm function and male fertility are closely related to pH dependent K⁺ current (KSper) in human sperm, which is most likely composed of Slo3 and its auxiliary subunit leucine-rich repeat-containing protein 52 (LRRC52). Onion peel extract (OPE) and its major active ingredient quercetin are widely used as fertility enhancers; however, the effect of OPE and quercetin on Slo3 has not been elucidated. The purpose of this study is to investigate the effect of quercetin on human Slo3 channels. Human Slo3 and LRRC52 were co-transfected into HEK293 cells and pharmacological properties were studied with the whole cell patch clamp technique. We successfully expressed and measured pH sensitive and calcium insensitive Slo3 currents in HEK293 cells. We found that OPE and its key ingredient quercetin inhibit Slo3 currents. Inhibition by quercetin is dose dependent and this degree of inhibition decreases with elevating internal alkalization and internal free calcium concentrations. Functional moieties in the quercetin polyphenolic ring govern the degree of inhibition of Slo3 by quercetin, and the composition of such functional moieties are sensitive to the pH of the medium. These results suggest that quercetin inhibits Slo3 in a pH and calcium dependent manner. Therefore, we surmise that quercetin induced depolarization in spermatozoa may enhance the voltage gated proton channel (Hv1), and activate non-selective cation channels of sperm (CatSper) dependent calcium influx to trigger sperm capacitation and acrosome reaction.


Asunto(s)
Humanos , Masculino , Reacción Acrosómica , Calcio , Fertilidad , Células HEK293 , Concentración de Iones de Hidrógeno , Cebollas , Fosfatidilinositoles , Protones , Quercetina , Capacitación Espermática , Espermatozoides
16.
Radiation Oncology Journal ; : 232-248, 2019.
Artículo | WPRIM | ID: wpr-786567

RESUMEN

Proton beams have been used for cancer treatment for more than 28 years, and several technological advancements have been made to achieve improved clinical outcomes by delivering more accurate and conformal doses to the target cancer cells while minimizing the dose to normal tissues. The state-of-the-art intensity modulated proton therapy is now prevailing as a major treatment technique in proton facilities worldwide, but still faces many challenges in being applied to the lung. Thus, in this article, the current status of proton therapy technique is reviewed and issues regarding the relevant uncertainty in proton therapy in the lung are summarized.


Asunto(s)
Neoplasias Pulmonares , Pulmón , Terapia de Protones , Protones , Incertidumbre
17.
Journal of Liver Cancer ; : 159-164, 2019.
Artículo en Inglés | WPRIM | ID: wpr-765712

RESUMEN

The treatment options available for patients with hepatocellular carcinoma (HCC) with portal vein invasion (PVI) include sorafenib, transarterial radioembolization (TARE), radiation therapy (RT), transarterial chemoembolization with RT, and proton beam irradiation. Herein, we present a case of HCC with segmental PVI that was managed via TARE. The patient had a 4 cm HCC that invaded the segment VIII portal vein branch without extrahepatic spread. Liver function was Child-Pugh grade A, and performance status was good. TARE was performed without any adverse events, and a radiological complete response (CR) was achieved. Thereafter, the patient was followed-up every 3–6 months without any further treatment, and the CR was maintained for >3 years. Therefore, TARE may be a useful alternative therapeutic option for patients with HCC exhibiting segmental PVI.


Asunto(s)
Humanos , Carcinoma Hepatocelular , Embolización Terapéutica , Hígado , Vena Porta , Protones , Radioterapia , Trombosis de la Vena
18.
Journal of Liver Cancer ; : 136-142, 2019.
Artículo en Inglés | WPRIM | ID: wpr-765716

RESUMEN

Proton beam therapy (PBT) is one of the advances in radiotherapy techniques, which enables dose escalation with lower probability of radiation-induced liver or gastrointestinal injuries. However, the chest wall proximal to the tumor can be affected by high dose irradiation. Here, we report on a 58-year-old male patient who presented with huge hepatocellular carcinoma, received treatment with transarterial chemoembolization and PBT, and developed severe chest wall pain due to radiation-induced myositis. The patient's symptoms were controlled by oral steroids.


Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , Carcinoma Hepatocelular , Hígado , Miositis , Terapia de Protones , Protones , Radioterapia , Esteroides , Pared Torácica
19.
Artículo en Chino | WPRIM | ID: wpr-772571

RESUMEN

Cancer therapy with accelerated proton or heavy ion beam is the most advanced radiotherapy technology, which is recognized by the international community at present. It is of great practical significance to study the medical proton and heavy ion accelerators and the radiotherapy technology, in order to promote the development of the advanced medical radiotherapy equipments and improve the quality of life of cancer patients in China. After a brief overview of cancer therapy with proton and heavy ion beam, this paper summarized and analyzed the application status of medical proton accelerators and medical heavy ion accelerators at home and abroad, and finally put forward the future development trends of medical proton and heavy ion accelerators and the radiotherapy technology, it can provide a reference for the progress and development strategies of the advanced radiotherapy equipments in China.


Asunto(s)
Humanos , China , Iones Pesados , Neoplasias , Terapéutica , Aceleradores de Partículas , Terapia de Protones , Protones , Calidad de Vida
20.
Artículo en Chino | WPRIM | ID: wpr-774161

RESUMEN

The deoxyribonucleic acid (DNA) molecule damage simulations with an atom level geometric model use the traversal algorithm that has the disadvantages of quite time-consuming, slow convergence and high-performance computer requirement. Therefore, this work presents a density-based spatial clustering of applications with noise (DBSCAN) clustering algorithm based on the spatial distributions of energy depositions and hydroxyl radicals (·OH). The algorithm with probability and statistics can quickly get the DNA strand break yields and help to study the variation pattern of the clustered DNA damage. Firstly, we simulated the transportation of protons and secondary particles through the nucleus, as well as the ionization and excitation of water molecules by using Geant4-DNA that is the Monte Carlo simulation toolkit for radiobiology, and got the distributions of energy depositions and hydroxyl radicals. Then we used the damage probability functions to get the spatial distribution dataset of DNA damage points in a simplified geometric model. The DBSCAN clustering algorithm based on damage points density was used to determine the single-strand break (SSB) yield and double-strand break (DSB) yield. Finally, we analyzed the DNA strand break yield variation trend with particle linear energy transfer (LET) and summarized the variation pattern of damage clusters. The simulation results show that the new algorithm has a faster simulation speed than the traversal algorithm and a good precision result. The simulation results have consistency when compared to other experiments and simulations. This work achieves more precise information on clustered DNA damage induced by proton radiation at the molecular level with high speed, so that it provides an essential and powerful research method for the study of radiation biological damage mechanism.


Asunto(s)
Algoritmos , Simulación por Computador , ADN , Efectos de la Radiación , Daño del ADN , Transferencia Lineal de Energía , Método de Montecarlo , Protones
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