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1.
Rev. medica electron ; 44(5): 892-902, sept.-oct. 2022.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1409775

ABSTRACT

RESUMEN La muerte súbita inesperada en epilepsia, se define como la muerte repentina -presenciada o no- de personas con epilepsia, no traumática ni por ahogamiento, con o sin evidencias de crisis, y en quienes el examen postmorten no revela una causa estructural o toxicológica de muerte. El objetivo de esta revisión es describir las evidencias más recientes, publicadas en la literatura, sobre la participación crucial del tallo encefálico en la fisiopatología de la muerte súbita inesperada en epilepsia. Se realizó una búsqueda bibliográfica en la base de datos computarizada PubMed. Los estudios en modelos animales han demostrado que los mecanismos de la muerte súbita inesperada en epilepsia involucran un primer evento mediado por una crisis, seguido por la despolarización cortical, que se propaga al tallo encefálico y que resulta en una disfunción autonómica causante de apnea central, edema pulmonar o arritmia cardiaca. Los estudios en humanos se han apoyado en las imágenes de resonancia magnética para evaluar el papel de diferentes áreas del tallo encefálico en la muerte súbita inesperada en epilepsia. Las evidencias acumuladas por la literatura, tanto en estudios con animales como humanos, evidencian el papel fundamental desempeñado por las estructuras del tallo encefálico en la fisiopatología de la muerte súbita inesperada en epilepsia.


ABSTRACT Sudden unexpected death in epilepsy is defined as the sudden death-whether witnessed or not-of people with epilepsy, not traumatic or due to drowning, with or without evidence of seizures, and in whom postmortem examination does not reveal a structural or toxicological cause of death. The aim of this review is to describe the most recent evidence published in the literature, on the crucial involvement of the brain stem in the pathophysiology of sudden unexpected death in epilepsy. A bibliographic search was conducted in PubMed computerized database. Studies in animal models have shown that the mechanisms of sudden unexpected death in epilepsy involve a first seizure-mediated event, followed by cortical depolarization, which spreads to the brainstem and results in autonomic dysfunction causing central apnea, pulmonary edema or cardiac arrhythmia. Studies in humans have relied on magnetic resonance imaging to assess the role of the brainstem in sudden unexpected death in epilepsy. The evidence accumulated in the literature, both in animal and in human studies, shows the role played by brainstem structures in the pathophysiology of sudden unexpected death in epilepsy.

2.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 108-116, 2022.
Article in Chinese | WPRIM | ID: wpr-940214

ABSTRACT

ObjectiveModern scientific methods and techniques were used to scientifically characterize the traditional softening process of Corydalis Rhizoma, so as to clarify the scientificity and rationality of the traditional process, and provide reference for inheriting the processing methods and experience of traditional Chinese medicine. MethodLow-field nuclear magnetic resonance imaging (LF-NMR/MRI) was used to characterize the water types and distribution in the softening process of Corydalis Rhizoma. Samples during the softening process was cut into thick slices and its section was observed by stereoscopic microscope. High performance liquid chromatography (HPLC) was employed to determine the content change of tetrahydropalmatine during the softening process with the mobile phase of methanol-0.1% phosphoric acid solution (60∶40, triethylamine regulated to pH 6.5) and detection wavelength at 280 nm. The determination method of softening endpoint of Corydalis Rhizoma was simulated by texture analyzer (hand pinch method), and the softening degree of the finished products was determined after optimizing the relevant parameters. ResultLF-NMR/MRI showed that the water could penetrate through the core and distribute evenly in Corydalis Rhizoma softened by Zhangbang method. The water first entered into the medicinal material from the epidermis and stem marks in the soaking stage as the form of free water, and then penetrated into the inner core to achieve redistribution in the moistening stage. Under stereoscopic microscope, it was observed that Corydalis Rhizoma softened by the Zhangbang method could be sliced well, but the core bursting slices were easy to appear if the softening time was not enough, and the softening of samples was caused by the keratine-like powder after absorbing water. HPLC measurement showed that the loss of tetrahydropalmatine in the softening method was small, its content decreased about 5% in the soaking process, and its content was almost unchanged during the moistening process. The softening degree of Corydalis Rhizoma could be quantified by the texture analyzer, and the optimum parameters were 2 mm·s-1 of speed before test, test speed and speed after test, 20 g of the trigger force, 20% of compression degree. The compressive force of the qualified softened Corydalis Rhizoma was 12.75-15.69 N with the relative standard deviation (RSD) of 6.8%. ConclusionModern scientific methods and techniques can characterize the scientificity and rationality of the traditional processing methods, and confirm that the Zhangbang softening method has the advantages of high efficiency, convenience and small loss of index components. The texture analyzer can simulate the softening endpoint judgment method (hand pinch method), and realize the goal from subjective experience judgment to objective technology quantification, which has a good demonstration role for the modern inheritance of traditional processing technology.

3.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 108-116, 2022.
Article in Chinese | WPRIM | ID: wpr-940117

ABSTRACT

ObjectiveModern scientific methods and techniques were used to scientifically characterize the traditional softening process of Corydalis Rhizoma, so as to clarify the scientificity and rationality of the traditional process, and provide reference for inheriting the processing methods and experience of traditional Chinese medicine. MethodLow-field nuclear magnetic resonance imaging (LF-NMR/MRI) was used to characterize the water types and distribution in the softening process of Corydalis Rhizoma. Samples during the softening process was cut into thick slices and its section was observed by stereoscopic microscope. High performance liquid chromatography (HPLC) was employed to determine the content change of tetrahydropalmatine during the softening process with the mobile phase of methanol-0.1% phosphoric acid solution (60∶40, triethylamine regulated to pH 6.5) and detection wavelength at 280 nm. The determination method of softening endpoint of Corydalis Rhizoma was simulated by texture analyzer (hand pinch method), and the softening degree of the finished products was determined after optimizing the relevant parameters. ResultLF-NMR/MRI showed that the water could penetrate through the core and distribute evenly in Corydalis Rhizoma softened by Zhangbang method. The water first entered into the medicinal material from the epidermis and stem marks in the soaking stage as the form of free water, and then penetrated into the inner core to achieve redistribution in the moistening stage. Under stereoscopic microscope, it was observed that Corydalis Rhizoma softened by the Zhangbang method could be sliced well, but the core bursting slices were easy to appear if the softening time was not enough, and the softening of samples was caused by the keratine-like powder after absorbing water. HPLC measurement showed that the loss of tetrahydropalmatine in the softening method was small, its content decreased about 5% in the soaking process, and its content was almost unchanged during the moistening process. The softening degree of Corydalis Rhizoma could be quantified by the texture analyzer, and the optimum parameters were 2 mm·s-1 of speed before test, test speed and speed after test, 20 g of the trigger force, 20% of compression degree. The compressive force of the qualified softened Corydalis Rhizoma was 12.75-15.69 N with the relative standard deviation (RSD) of 6.8%. ConclusionModern scientific methods and techniques can characterize the scientificity and rationality of the traditional processing methods, and confirm that the Zhangbang softening method has the advantages of high efficiency, convenience and small loss of index components. The texture analyzer can simulate the softening endpoint judgment method (hand pinch method), and realize the goal from subjective experience judgment to objective technology quantification, which has a good demonstration role for the modern inheritance of traditional processing technology.

4.
Chinese Journal of Medical Instrumentation ; (6): 469-472, 2021.
Article in Chinese | WPRIM | ID: wpr-888648

ABSTRACT

Quench of magnetic resonance imaging system refers to the process that the superconducting condition inside the magnet is destroyed due to some reason. The large current stored in the coil is quickly converted into heat at the place where the resistance is formed, and a large amount of liquid helium in the magnet is evaporated. If it happens, it will cause huge loss to the user. We introduce the real cases of 1.5 T magnetic resonance imaging system's quench fault, maintenance treatment and management improvement, which can be used for reference by various medical institutions, so as to better strengthen the operation and maintenance management of magnetic resonance imaging system, so as to avoid the occurrence of out of tolerance fault, and do a good job in the guarantee work after the out of tolerance fault.


Subject(s)
Helium , Magnetic Resonance Imaging , Magnets
5.
Article in English | IMSEAR | ID: sea-150803

ABSTRACT

Counterfeiting of drugs has now become a lucrative multi-billion dollar business that threatens the effective delivery of health care services. Apart from Africa and other marginally developed parts of the world, the developed economies are equally not spared from the bane of this trade. To combat this menace, concerted efforts are needed from various facets of the community. In addition to visual inspections, sophisticated analytical tools are usually required in order to successfully distinguish counterfeits from the real stuffs. Attempt is made in this review to summarize the recent applications of these tools in keeping track with counterfeit drug flow. These are discussed under the headings of different approaches, including Near Infrared Spectroscopy, Raman Spectroscopy, Fluorescence and Phosphorescence measurements, Nuclear Magnetic Resonance imaging, X-ray and radio frequency analysis. In the quest to maintain their profit margin, the perpetrators of counterfeit pharmaceuticals will continue to develop ingenious ways to circumvent regulatory systems. Therefore, relentless efforts should continue to be deployed toward research and development in low cost, fast and efficient ways of detecting counterfeit drug at different stages of its existence.

6.
China Oncology ; (12)1998.
Article in Chinese | WPRIM | ID: wpr-548593

ABSTRACT

Integrin ?V?3, one of the major members of the integrin family, plays a pivotal role in tumor angiogenesis because it mediates the cell-extracellular matrix and cell to cell adhesion as well as controls cells proliferation, differentiation, cellular modality and motility.Due to restricted high-expressions in tumors, integrin ?V?3, is considered a suitable targeting receptor for tumor diagnosis.In the past decade, several molecular imaging tracers for integrin ?V?3, have been used to noninvasively visualize its expression in tumor tissues and angiogenic blood vessels through the usage of nuclear imaging, nuclear magnetic resonance imaging, ultrasound, and optical imaging.Noninvasive detection of integrin ?V?3, expression can potentially be used for tumor diagnosis and prognosis.The current imaging probes used to target integrin ?V?3, through usage of different technologies are briefly recapitulated in this review.

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