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1.
Acta neurol. colomb ; 40(1): e8, ene.-mar. 2024. graf
Article de Espagnol | LILACS-Express | LILACS | ID: biblio-1573716

RÉSUMÉ

Resumen Introducción: El síndrome de Percheron es una entidad infrecuente de difícil determinación clínica y que es causada por la oclusión de la arteria de Percheron. Presentación del caso: Paciente masculino de 71 años que llega obnubilado al servicio de urgencias, con disartria, hemiparesia izquierda, signo de Babinski bilateral, ptosis palpebral derecha, con exotropía, limitación total de la aducción del ojo derecho y abducción parcial del izquierdo, con imposibilidad de supraducción e infraducción de ambos ojos. Además, tenía reflejo oculocefálico vertical ausente bilateralmente y horizontal derecho ausente, pupilas anisocóricas y reflejo fotomotor ausente en ambos ojos. La imágenes obtenidas por resonancia magnética nuclear (RMN) (T1W, T2, T2-FLAIR y técnicas de difusión) demostraron que hubo un infarto de la arteria de Percheron. El paciente se mantuvo por 10 días hospitalizado y evolucionó favorablemente. Discusión: El síndrome de Percheron cursa con una triada clásica caracterizada por alteración de la conciencia, deterioro cognitivo y parálisis de la mirada vertical, a lo que se le añade hemiplejía, ataxia cerebelosa y déficit oculomotor y, si se acompaña de lesiones mesencefálicas, se produce un síndrome tálamo-peduncular. La sospecha clínica de esta patología constituye un desafío en la práctica médica, debido a la infrecuencia de presentación, variabilidad de alteraciones neurológicas y la dificultad que ofrecen los estudios imagenológicos de urgencia. Conclusiones: Hemos descrito una entidad infrecuente y de difícil determinación clínica, en la cual, los criterios para el diagnóstico son fundamentalmente imagenológicos, siendo de elección la RMN. La evolución y el pronóstico dependerán de la extensión del proceso, las estructuras involucradas, el diagnóstico y su tratamiento oportuno.


Abstract Introduction: Percheron Syndrome is an infrequent entity that is difficult to determine clinically, caused by the occlusion of the Percheron artery. Case presentation: We present a 71-year-old male patient admitted to the emergency department: obtunded, with dysarthria, left hemiparesis, bilateral Babinsky's sign, right palpebral ptosis, with exotropia, total adduction limitation of the right eye and partial adduction of the right eye. abduction of the left with impossibility of supraduction and infraduction of both eyes. Absent vertical oculocephalic reflex bilaterally and absent right horizontal. Anisochoric pupils, photomotor reflex absent in both eyes. The images obtained by Nuclear Magnetic Resonance (T1W, T2, T2-FLAIR and diffusion techniques) showed infarction of the Percheron artery. He remained hospitalized for 10 days, and evolved favorably. Discussion. Percheron Syndrome presents with a classic triad characterized by altered consciousness, cognitive impairment and paralysis of vertical gaze, to which is added hemiplegia, cerebellar ataxia and oculomotor deficit, if accompanied by mesencephalic lesions, producing a Thalamopeduncular Syndrome. The clinical suspicion of this pathology constitutes a challenge in medical practice, due to the infrequency of presentation, variability of neurological alterations and the difficulty offered by emergency imaging studies. Conclusions. We have described a rare entity that is difficult to determine clinically, in which the criteria for diagnosis are fundamentally imaging, with MRI being the choice. The evolution and prognosis will depend on the extent of the process, structures involved in addition to the diagnosis and timely treatment.

2.
Chinese Journal of Biologicals ; (12): 129-137, 2024.
Article de Chinois | WPRIM | ID: wpr-1006850

RÉSUMÉ

@#Objective To evaluate the stability of polyribosylribitol phosphate(PRP),the basic structure of capsular polysaccharide of Haemophilus influenzae type b(Hib),in the preparation of Hib conjugate vaccine.Methods The structures of the prepared Hib polysaccharides,polysaccharide derivatives and protein-conjugated polysaccharides were analyzed by nuclear magnetic resonance spectroscopy(NMR).Results The detection results of the prepared Hib polysaccharides,polysaccharide derivatives and protein-conjugated polysaccharides all met the requirements of relevant standards of Chinese Pharmacopoeia(VolumeⅢ,2020 edition),and the NMR spectra showed no significant change.Conclusion The basic structure PRP of the main carbohydrate antigen of Hib conjugate vaccine had no change during the vaccine manufacturing.

3.
Acta ortop. mex ; 37(4): 203-206, jul.-ago. 2023. tab, graf
Article de Espagnol | LILACS-Express | LILACS | ID: biblio-1568756

RÉSUMÉ

Resumen: Introducción: el acromion es una pequeña porción de la escápula que se extiende hacia la región anterior desde la espina de la escápula. Tradicionalmente se clasifica al acromion por la forma de su superficie inferior en un plano sagital. Se ha encontrado que la morfología acromial está rela-cionada con la lesión del manguito rotador. Objetivo: determinar la asociación entre el tipo de acromion con una mayor incidencia de ruptura de manguito rotador. Población de estudio: pacientes que acudan al Servicio de Traumatología y Ortopedia de un hospital privado de tercer nivel en la ciudad de Monterrey por hombro doloroso y a los cuales se les haya realizado una resonancia magnética simple de hombro. Material y métodos: se realizó un estudio de tipo transversal, retrospectivo y descriptivo, en el cual se revisaron 273 estudios de resonancia magnética en pacientes que cumplieran los criterios de inclusión. Se reportó el tipo de acromion según la clasificación morfológica en tipo I a IV y el estado del manguito rotador: sin ruptura, ruptura parcial o ruptura completa, haciendo una comparación entre hombro derecho e izquierdo. Resultados: se obtuvo un valor de p = 0.473 por lo que se concluye que no existe una asociación entre el tipo de acromion y el estado del manguito rotador. Conclusión: en el presente estudio, a diferencia de lo publicado en la literatura, se obtuvo que el acromion tipo II fue al que se asoció la mayoría de los casos con ruptura del manguito rotador.


Abstract: Introduction: the acromion is a small portion of the scapula that extends towards the anterior region from the spine of the scapula. Traditionally, the acromion is classified by the shape of its inferior surface in a sagittal plane. Acromial morphology has been found to be related to rotator cuff injury. Objective: to determine the association between the type of acromion with a higher incidence of rotator cuff rupture. Study population: patients who come to the Traumatology and Orthopedics Service of a third level hospital at Monterrey, Mexico, due to a painful shoulder and who have undergone a simple magnetic resonance of the shoulder. Material and methods: a cross-sectional, retrospective and descriptive study was carried out, in which 273 magnetic resonance studies were reviewed in patients who met the inclusion criteria. The type of acromion was reported according to the morphological classification in type I to IV and the state of the rotator cuff: without rupture, partial rupture or complete rupture, making a comparison between right and left shoulder. Results: in this study we found a value of p = 0.473 which concludes that there is no relation between the type of acromion and the injury of the rotator cuff. Conclusion: in the present study, unlike what has been published in the literature, it was found that type II acromion was the one that was associated in most cases with a rotator cuff tear.

4.
Rev. MED ; 31(1): 141-146, ene.-jun. 2023. tab
Article de Espagnol | LILACS-Express | LILACS | ID: biblio-1575831

RÉSUMÉ

Resumen: Las infecciones osteoarticulares en pacientes pediátricos están asociadas a morbilidad significativa y riesgo de secuelas funcionales o anatómicas, que requieren intervenciones quirúrgicas, en ciertas ocasiones. La sacroileítis piógena (SP) es una infección bacteriana osteoarticular que abarca un pequeño porcentaje del total de las artritis sépticas. La sintomatología es imprecisa, lo que hace retrasar el diagnóstico de la enfermedad y, consecuentemente, llevar a posibles complicaciones como abscesos, sepsis y deformación de las articulaciones. En la actualidad, la resonancia magnética nuclear (RMN) es el método diagnóstico más útil en razón a su relativamente fácil acceso y alta sensibilidad. El inicio del manejo antibiótico adecuado implica una rápida regresión de los síntomas. Presentamos el caso clínico de una paciente escolar atendida en un hospital de Bogotá, Colombia, quien presentó un cuadro de SP, sospechado con base en la anamnesis y examen físico para finalmente ser confirmado por imagenología y cultivo microbiológico.


Abstract: Osteoarticular infections in pediatric patients are associated with significant morbidity and the risk of functional and/or anatomical sequelae, often requiring surgical interventions. Pyogenic sacroiliitis is a rare bacterial infection affecting the osteoarticular region, accounting for a small percentage of all septic arthritis cases. The symptomatology is imprecise, leading to delayed diagnosis and potential complications such as abscesses, sepsis and joint deformities. Currently, nuclear magnetic resonance is the most useful diagnostic method due to its relatively easy accessibility and high sensitivity. Initiating appropriate antibiotic treatment results in a rapid regression of symptoms. We present the clinical case of a school- aged patient treated at a hospital in Bogotá, Colombia. The patient exhibited symptoms indicative of pyogenic sacroiliitis, suspected based on the anamnesis and physical examination, and later confirmed through imaging and microbiological culture.


Resumo: As infecções osteoarticulares em pacientes pediátricos estão associadas a morbidade significativa e risco de sequelas funcionais ou anatômicas, que podem requerer intervenções cirúrgicas em certas ocasiões. A sacroileíte piogênica (SP) é uma infecção bacteriana osteoarticular que abrange uma pequena porcentagem do total de artrites sépticas. A sintomatologia é imprecisa, o que pode atrasar o diagnóstico da doença e, consequentemente, levar a complicações como abscessos, sepse e deformação das articulações. Atualmente, a ressonância magnética nuclear (RMN) é o método diagnóstico mais útil devido ao seu acesso relativamente fácil e alta sensibilidade. O início do manejo antibiótico adequado implica uma rápida regressão dos sintomas. Apresentamos o caso clínico de uma paciente escolar atendida em um hospital em Bogotá, Colômbia, que apresentou um quadro de SP, suspeito com base na anamnese e exame físico, sendo posteriormente confirmado por imagem e cultura microbiológica.

5.
Rev. cuba. med ; 62(1)mar. 2023.
Article de Espagnol | LILACS, CUMED | ID: biblio-1449994

RÉSUMÉ

Introducción: Las malformaciones de Arnold-Chiari, son un grupo heterogéneo de desórdenes neurológicos caracterizados por alteraciones dentro de las regiones del cerebelo, tallo cerebral y unión cráneo-cervical; todas resultan en un desplazamiento inferior del cerebelo hacia el canal espinal por el foramen magno, sea en conjunto con la médula inferior o no. Objetivo: Describir los hallazgos clínicos, estudios complementarios, criterios diagnósticos, conducta terapéutica y evolución, en un caso con malformación de Chiari tipo I con siringomielia. Presentación de caso: Se presenta a una paciente con cefalea de curso insidioso a la que se le diagnostica malformación de Chiari tipo I con siringomielia, que requirió tratamiento neuroquirúrgico. La evolución posoperatoria fue favorable. Conclusiones: La malformación de Arnold-Chiari es una entidad rara; la aparición de la resonancia magnética nuclear ha permitido que su diagnóstico aumente y por tanto, su incidencia. El caso presentado tuvo un curso clínico clásico(AU)


Introduction: Arnold-Chiari malformations are a heterogeneous group of neurological disorders characterized by alterations within the regions of the cerebellum, brain stem and craniocervical junction; all result in inferior displacement of the cerebellum into the spinal canal through the foramen magnum, whether in conjunction with the inferior cord or not. Objective: To describe the clinical findings, complementary studies, diagnostic criteria, therapeutic approach and evolution, in a case with type I Chiari malformation with syringomyelia. Case report: A patient with an insidious course of headache is reported. She was diagnosed with type I Chiari malformation with syringomyelia, which required neurosurgical treatment. The postoperative evolution was favorable. Conclusions: Conclusions: Arnold-Chiari malformation is a rare entity. the appearance of nuclear magnetic resonance has allowed it to be diagnosed and therefore its incidence has increased. The reported case had a classic clinical course(AU)


Sujet(s)
Humains , Mâle , Femelle , Malformation d'Arnold-Chiari/imagerie diagnostique , Spectroscopie par résonance magnétique/méthodes , Céphalées/épidémiologie
6.
Article de Chinois | WPRIM | ID: wpr-973756

RÉSUMÉ

ObjectiveThe hygroscopic properties of Mume Flos decoction pieces were studied from the perspectives of macroscopic[water activity(Aw)] and microscopic(water molecular mobility), which provided a theoretical basis for the determination of the safe storage moisture content. MethodAdsorption isotherm of Mume Flos decoction pieces was obtained by static weighing method, and seven common hygroscopic models were fitted and estimated. The best model was selected according to the principle that determination coefficient(R2) was closer to 1, residual sum of squares(RSS) was closer to 0 and Akaike information criterion(AIC) was smaller. According to the optimal model, the absolute and relative safe moisture contents of Mume Flos decoction pieces at 25, 35, 45 ℃ was calculated. Low-field nuclear magnetic resonance(LF-NMR) was used to measure the water molecular mobility in the hygroscopic process of Mume Flos decoction pieces. ResultThe best model to describe the adsorption isotherm of Mume Flos decoction pieces was the Peleg model. According to the model expression, the absolute safe moisture contents of Mume Flos decoction pieces at 25, 35, 45 ℃ were 9.59%, 7.96% and 7.68%, and the relative safe moisture contents were 13.05%, 11.99%, 11.77%, respectively. Mume Flos decoction pieces all contained two water states during the process of hygroscopic absorption at different temperatures, namely bound water T21 and free water T22. During the process of hygroscopic absorption, bound water had the largest increase in peak area. The sum of peak areas of the bound water and free water had a good linear relationship with the moisture contents, and the R2 were 0.959 9, 0.911 8 and 0.974 7 at 25, 35, 45 ℃, respectively. When Aw<0.57, T21 did not change, and the water molecular mobility remained unchanged. When Aw>0.57, T21 showed an increasing trend, and the water molecular mobility increased. The moisture contents of Mume Flos decoction pieces were 8.44%, 6.81% and 6.25% when the water molecular mobility increased at 25, 35, 45 ℃, respectively. ConclusionCombined with the theory of water activity and water molecular mobility, 6.25% is recommended as the safe storage moisture content of Mume Flos decoction pieces, this study can provide reference for determining the safe storage moisture content of other decoction pieces.

7.
Article de Chinois | WPRIM | ID: wpr-973759

RÉSUMÉ

ObjectiveTo establish the identification method of Dalbergiae Odoriferae Lignum(DOL) and its counterfeits by nuclear magnetic resonance hydrogen spectrum(1H-NMR) combined with multivariate statistical analysis. Method1H-NMR spectra of DOL and its counterfeits were obtained by NMR, and the full composition information was established and transformed into a data matrix, and the detection conditions were as follows:taking dimethyl sulfoxide-d6(DMSO-d6) containing 0.03% tetramethylsilane(TMS) as the solvent, the constant temperature at 298 K(1 K=-272.15 ℃), pulse interval of 1.00 s, spectrum width of 12 019.23 Hz, the scanning number of 16 times, and the sampling time of 1.08 s. Similarity examination and hierarchical cluster analysis(HCA) were performed on the data matrix of DOL and its counterfeits, and orthogonal partial least squares-discriminant analysis(OPLS-DA) was used to analyze the data matrix and identify the differential components between them. In the established OPLS-DA category variable value model, the category variable value of DOL was set as 1, and the category variable value of the counterfeits was set as 0, and the threshold was set as ±0.3, in order to identify the commercially available DOL. The OPLS-DA score plot was used to determine the types of counterfeits in commercially available DOL, and it was verified by thin layer chromatography(TLC). ResultThe results of similarity analysis and HCA showed that there was a significant difference between DOL and its counterfeits. OPLS-DA found that the differential component between DOL and its counterfeits was trans-nerolidol. The established category variable value model could successfully identify the authenticity of the commercially available DOL. The results of the OPLS-DA score plot showed that there were heartwood of Dalbergia pinnata and D. cochinchinensis in the commercially available DOL, and were consistent with the TLC verification results. ConclusionThere is a phenomenon that heartwood of D. pinnata and D. cochinchinensis are sold as DOL in the market. 1H-NMR combined with multivariate statistical analysis can effectively distinguish DOL and its counterfeits, which can provide a reference for the identification of them.

8.
Article de Chinois | WPRIM | ID: wpr-961108

RÉSUMÉ

@#Metabolomics reflects the endogenous metabolite changes in organisms through qualitative and quantitative detection of small molecules in biological samples, revealing the metabolic changes during disease development. Metabolomic studies of periodontitis further elucidate the etiology, diagnosis and predictive markers of periodontitis at the levels of metabolites and metabolic pathways. In this paper, the concept and research methods of metabonomics were summarized, and the current status of the metabonomics of saliva and gingival crevicular fluid in the study of periodontitis was reviewed. Previous studies have shown that metabolites such as short-chain fatty acids and amino acids and metabolic pathways such as glutamic acid and pyrimidine metabolism might promote the occurrence of periodontitis, and it was suggested that lactic acid, γ-amino-butyrate, butyric acid and lysophosphatidic acid might be potential diagnostic markers of periodontitis. The metabolomics study of periodontitis still faces challenges such as high heterogeneity of results and fluctuation of metabolites. In the future, its study could be optimized through multicenter prospective studies to provide fresh approaches for the etiology and diagnosis of periodontitis.

9.
Yao Xue Xue Bao ; (12): 3599-3607, 2023.
Article de Chinois | WPRIM | ID: wpr-1004639

RÉSUMÉ

Quantitative nuclear magnetic resonance (qNMR) technology has significant advantages in quantification due to its simple sample processing and high reproducibility. Two-dimensional qNMR analysis, which can solve the quantification problem of different components in complex systems, has gradually been applied in medicine, food, metabonomics, chemical engineering, and other fields. This paper reviews the analysis methods, influencing factors, experimental optimization, application fields, and other aspects of qNMR to promote its wide and effective application.

10.
Chinese Journal of Biologicals ; (12): 1491-1496+1502, 2023.
Article de Chinois | WPRIM | ID: wpr-1005874

RÉSUMÉ

@#Objective To develop an indirect ELISA-based peptide scanning method combined with nuclear magnetic resonance(NMR)technique for the epitope identification of calcitonin gene-related peptide(CGRP)antibodies.Methods The antigen binding activities of two antibodies(new CGRP antibody and control antibody)were determined by indirect ELISA using each truncated CGRP fragment as coating antigen,and the linear epitope was analyzed according to the EC50value of four-parameter curve. Two-dimensional hydrogen-nitrogen correlation(2D1H-15N HSQC)spectrum of CGRP were acquired by NMR technique,and the binding of antibodies to the arginine of CGRP were analyzed through the disturbance of the antibodies to CGRP signals. Specific arginine modifications were detected by liquid chromatography-mass spectrum(LCMS) and NMR technique,and two arginine resonances were assigned on CGRP by correlating the rank order of the modification rate.ResultsThe antigen binding activities of two antibodies with CGRP(1-37),CGRP(19-37)and CGRP(25-37)showed dose-response relationships,and were fitted with four-parameter equation. However,there were no significant antigen binding with CGRP(1-18),CGRP(19-24)and CGRP(25-37)without C-terminal amide. The linear epitopes of both antibodies were located at the C-terminal of CGRP. The resonances of arginine ε-NH in 2D1H-15N HSQC spectrum disappeared in the presence of the control antibody;and the resonances appeared in the presence of the new antibody. The arginine R11 and R18 of CGRP could bind to the control antibody,but not to the new antibody. The NMR assignment for the arginine resonances were made by correlating the relative ranking of the modification rate where signals A and B arose from R11 ε-NH and R18 ε-NH respectively.ConclusionIn this study,the linear and conformational epitopes of new CGRP antibody and control antibody were identified based on the methods of ELISA and NMR,which may provide a theoretical basis for the design of the candidate therapeutic CGRP antibodies.

11.
Zhonghua laodong weisheng zhiyebing zazhi ; Zhonghua laodong weisheng zhiyebing zazhi;(12): 57-62, 2023.
Article de Chinois | WPRIM | ID: wpr-970713

RÉSUMÉ

Acute carbon monoxide poisoning and its delayed encephalopathy have obvious damage to the central nervous system. There are different neuroimaging changes in different stages of the disease, and they are relatively specific. This article reviews the clinical research progress on the imaging changes of carbon monoxide poisoning and delayed encephalopathy, including computed tomography (CT) , conventional magnetic resonance imaging (MRI) , diffusion weighted imaging (DWI) , diffusion tensor imaging (DTI) , diffusion kurtosis imaging (DKI) , magnetic resonance spectroscopy (MRS) and other imaging changes reflecting the function and metabolic state of the brain tissue.


Sujet(s)
Humains , Encéphalopathies/étiologie , Intoxication au monoxyde de carbone/imagerie diagnostique , Imagerie par résonance magnétique de diffusion , Imagerie par tenseur de diffusion , Imagerie par résonance magnétique , Tomodensitométrie , Spectroscopie par résonance magnétique
12.
Chinese Journal of Biotechnology ; (12): 1633-1643, 2023.
Article de Chinois | WPRIM | ID: wpr-981159

RÉSUMÉ

The multiple-step cleavage of amyloid precursor protein (APP) generates amyloid-β peptides (Aβ), highly toxic molecules causing Alzheimer's disease (AD). The nonspecific cleavage between the transmembrane region of APP (APPTM) and γ-secretase is the key step of Aβ generation. Reconstituting APPTM under physiologically-relevant conditions is crucial to investigate how it interacts with γ-secretase and for future AD drug discovery. Although producing recombinant APPTM was reported before, the large scale purification was hindered by the use of biological protease in the presence of membrane protein. Here, we expressed recombinant APPTM in Escherichia coli using the pMM-LR6 vector and recovered the fusion protein from inclusion bodies. By combining Ni-NTA chromatography, cyanogen bromide cleavage, and reverse phase high performance liquid chromatography (RP-HPLC), isotopically-labeled APPTM was obtained in high yield and high purity. The reconstitution of APPTM into dodecylphosphocholine (DPC) micelle generated mono dispersed 2D 15N-1H HSQC spectra in high quality. We successfully established an efficient and reliable method for the expression, purification and reconstruction of APPTM, which may facilitate future investigation of APPTM and its complex in more native like membrane mimetics such as bicelle and nanodiscs.


Sujet(s)
Humains , Précurseur de la protéine bêta-amyloïde/composition chimique , Micelles , Amyloid precursor protein secretases/métabolisme , Spectroscopie par résonance magnétique , Protéines recombinantes
13.
J. forensic med ; Fa yi xue za zhi;(6): 144-150, 2023.
Article de Anglais | WPRIM | ID: wpr-981848

RÉSUMÉ

OBJECTIVES@#To identify 1-(4-fluorophenyl)-2-(1-pyrrolidinyl) pentan-1-one (4-F-α-PVP) analog 1-(4-fluoro-3-methyl phenyl)-2-(1-pyrrolidinyl) pentan-1-one (4-F-3-Methyl-α-PVP) hydrochloride without reference substance.@*METHODS@#The direct-injection electron ionization-mass spectrometry (EI-MS), GC-MS, electrospray ionization-high resolution mass spectrometry (ESI-HRMS), ultra-high performance liquid chromatography-high resolution tandem mass spectrometry (UPLC-HRMS/MS), nuclear magnetic resonance (NMR), ion chromatography and Fourier transform infrared spectroscopy (FTIR) were integrated utilized to achieve the structural analysis and characterization of the unknown compound in the sample, and the cleavage mechanism of the fragment ions was deduced by EI-MS and UPLC-HRMS/MS.@*RESULTS@#By analyzing the direct-injection EI-MS, GC-MS, ESI-HRMS and UPLC-HRMS/MS of the compound in the samples, it was concluded that the unknown compound was a structural analog of 4-F-α-PVP, possibly with one more methyl group in the benzene ring. According to the analysis results of 1H-NMR and 13C-NMR, it was further proved that the methyl group is located at the 3-position of the benzene ring. Since the actual number of hydrogen in 1H-NMR analysis was one more than 4-F-3-Methyl-α-PVP neutral molecule, it was inferred that the compound existed in the form of salt. Ion chromatography analysis results showed that the compound contained chlorine anion (content 11.14%-11.16%), with the structural analysis of main functional group information by FTIR, the unknown compound was finally determined to be 4-F-3-Methyl-α-PVP hydrochloride.@*CONCLUSIONS@#A comprehensive method using EI-MS, GC-MS, ESI-HRMS, UPLC-HRMS/MS, NMR, ion chromatography and FTIR to identify 4-F-3-Methyl-α-PVP hydrochloride in samples is established, which will be helpful for the forensic science laboratory to identify this compound or other analog compounds.


Sujet(s)
Benzène , Chromatographie gazeuse-spectrométrie de masse/méthodes , Spectrométrie de masse ESI , Chromatographie en phase liquide à haute performance/méthodes
14.
Article de Chinois | WPRIM | ID: wpr-1029476

RÉSUMÉ

Objective:To investigate the mechanism of Mycobacterium tuberculosis ( Mtb) WhiB2 in the pathogenesis of tuberculosis. Methods:A recombinant vector of pET28a-WhiB2 for heterogeneous expression of WhiB2 was constructed. The target protein WhiB2 and the inclusion bodies were purified. The differences between denatured and non-denatured WhiB2 were analyzed by circular dichroism and nuclear magnetic resonance. Ferrous ion (Fe 2+ ) was used to restore the iron-sulfur cluster of WhiB2. The interaction between WhiB2 and the upstream promoter sequence of the WhiBMtb gene was analyzed by nuclear magnetic resonance. The tertiary structure of WhiB2 and interacting proteins were analyzed and protein structure alignment was performed based on bioinformatics. Results:The structure of the renatured WhiB2 was basically the same as that of the non-denatuous WhiB2. In addition, Fe 2+ could restore the iron-sulfur cluster of WhiB2. It was found that WhiB2 could bind to the upstream promoter sequence of the WhiBMtb/WhiB2Ms gene. Conclusions:Mtb WhiB2 played a key role in the pathogenesis of tuberculosis, which would contribute to future exploration of novel targets against Mtb.

15.
Article de Chinois | WPRIM | ID: wpr-995746

RÉSUMÉ

Nuclear magnetic resonance spectroscopy (NMRS) is a branch of spectroscopy, which can be used to determine the number, type and relative position of components in the mixture. Due to its high throughput, high sensitivity and high stability, especially its "fingerprint", non-destructive and non-biased detection of metabolites, NMRS has become one of the most commonly used analytical and detection techniques in metabolomics. Based on the research of clinical laboratory application, this review briefly expounds the technical principle of nuclear magnetic resonance spectroscopy, introduces the development and latest research results of nuclear magnetic resonance spectroscopy in biomedical application fields such as blood lipid analysis, tumor detection, prediction of mental and nervous system diseases, infectious diseases, nutrition and health management, and discusses the development prospect of clinical translational medicine.

16.
Article de Chinois | WPRIM | ID: wpr-995776

RÉSUMÉ

New techniques in clinical lipid measurements, such as vertical auto profile, nuclear magnetic resonance spectroscopy, electrospray differential mobility analysis and liquid chromatography-mass spectrometry/mass spectrometry, are becoming increasingly mature. Clinical application of these new techniques significantly promoted the use of new lipid parameters including the particle concentrations of low-density lipoprotein/high-density lipoprotein and other lipoprotein subtype in the risk stratification of atherosclerotic cardiovascular disease and in the efficacy monitoring of lipid-regulating therapy, above progress is helpful on developing new individualized and precise lipid management strategies. This review analyzed and summarized the research progress of the new techniques for lipid measurements in recent years, aiming to provide evidence to develop new ideas for the individualized and accurate lipid management in clinical practice.

17.
Zhongguo Zhong Yao Za Zhi ; (24): 6396-6402, 2023.
Article de Chinois | WPRIM | ID: wpr-1008838

RÉSUMÉ

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.


Sujet(s)
Protons , Médicaments issus de plantes chinoises/composition chimique , Fibre alimentaire , Spectroscopie par résonance magnétique
18.
Yao Xue Xue Bao ; (12): 3082-3089, 2023.
Article de Chinois | WPRIM | ID: wpr-999046

RÉSUMÉ

An LC-MS method with natural isotope abundance correction and a 1H NMR relative quantitative method were established to determine the deuterium incorporation of donafenib tosilate, a new deuterated drug molecule. First, the peak areas of isotopic impurities (non-deuterated and incompletely deuterated impurities) and deuterated drug were recorded through the single ion monitoring (SIM) mode of the established LC-MS method and then corrected in terms of the natural isotope abundance offered by ChemDraw soft, removing the nature isotope interference from 13C, 37Cl, etc. The corrected areas were subsequently used to calculate mol% of isotopologues (D0, D1, D2, D3) and Atom% D, namely, deuterium incorporation. In addition, a 1H qNMR experiment was conducted with the aromatic proton at δ 8.63 and the residual proton of isotopic impurities at δ 2.79 as quantitative peaks. The mixture of DMSO-d6 and D2O (10∶1) was employed as the solvent to change the spin-coupling between the residual proton and active hydrogen so that the residual proton could be measured as the single peak, and the sensitivity was greatly improved. The acquisition parameters were also optimized, and Atom% 1H and the deuterium incorporation were then calculated. The two methods were applied to samples of three commercial batches, and the testing results were almost consistent. Both methods proved accurate, sensitive, fast and independent of standard substances and accurate weighing, which could be applied to the determination of the deuterium incorporation of donafenib tosilate and provide a reference for other deuterated drugs.

19.
Rev. medica electron ; 44(5): 892-902, sept.-oct. 2022.
Article de Espagnol | LILACS-Express | LILACS | ID: biblio-1409775

RÉSUMÉ

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.

20.
Article | IMSEAR | ID: sea-216841

RÉSUMÉ

Aim: Demineralization can be arrested or reversed when remineralization agents are applied to incipient carious or noncavitated carious lesions. A large number of therapeutic agents, including nonfluoridated products, have been developed to promote enamel remineralization. This study aims to evaluate the efficacy of different remineralizing agents on artificially demineralized enamel lesions. Materials and Methods: The present in vitro study was conducted on 75 sound premolars divided into three groups of normal, demineralized (n = 15 each), and remineralized teeth (n = 45). The remineralized teeth were further subdivided into three groups (n = 15) as remineralized with 2% sodium fluoride (NaF), 2% NaF, and Psoralea corylifolia (bakuchi) and white mineral trioxide aggregate. Specimens of each group were treated with the above-mentioned remineralizing agents and then subjected to Vickers hardness number (VHN), scanning electron microscopy–energy dispersive X-ray (SEM-EDX), and magic-angle spinning nuclear magnetic resonance (MAS-NMR) for further evaluation. Results: The test results showed significantly the highest VHN and the emission peak of elements under the EDX test, such as calcium, phosphorous, oxygen, and fluorine with remineralized with NaF + bakuchi. MAS-NMR spectra showed fluorine and phosphorous peak in a group with NaF + bakuchi indicative of the increase in remineralization. NaF + bakuchi showed effective results in VHN, SEM-EDX, and MAS-NMR with no antagonist interaction. Conclusion: Thus, P. Corylifolia presents an advantage in enhancing remineralization and inhibiting demineralization for early carious lesions and can be used as a herbal extract for effective reduction in pathogenic bacteria.

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