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1.
J Am Soc Mass Spectrom ; 35(5): 960-971, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38616559

RESUMO

In Asia, some herbal preparations have been found to be adulterated with undeclared synthetic medicines to increase their therapeutic efficiency. Many of these adulterants were found to be toxic when overdosed and have been documented to bring about severe, even life-threatening acute poisoning events. The objective of this study is to develop a rapid and sensitive ambient ionization mass spectrometric platform to characterize the undeclared toxic adulterated ingredients in herbal preparations. Several common adulterants were spiked into different herbal preparations and human sera to simulate the clinical conditions of acute poisoning. They were then sampled with a metallic probe and analyzed by the thermal desorption-electrospray ionization mass spectrometry. The experimental parameters including sensitivity, specificity, accuracy, and turnaround time were prudently optimized in this study. Since tedious and time-consuming pretreatment of the sample is unnecessary, the toxic adulterants could be characterized within 60 s. The results can help emergency physicians to make clinical judgments and prescribe appropriate antidotes or supportive treatment in a time-sensitive manner.


Assuntos
Contaminação de Medicamentos , Preparações de Plantas , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização por Electrospray/métodos , Humanos , Preparações de Plantas/análise , Preparações de Plantas/química , Serviços Médicos de Emergência/métodos
2.
J Food Drug Anal ; 27(2): 415-427, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30987713

RESUMO

The unintentional ingestion of toxic compounds in herbs is not uncommon in many parts of the world. To provide timely and life-saving care in the emergency department, it is essential to develop a point-of-care analytical method that can rapidly identify these toxins in herbs. Since electrospray laser desorption ionization mass spectrometry (ELDI/MS) has been successfully used to characterize non-volatile chemical compounds without sample preparation, it was used to identify toxic herbal compounds in this study. The herbal toxins were collected either by sweeping a metallic probe across the surface of a freshly cut herb section or by directly sampling extracts of ground herbal powder. The analytes on the probe were then desorbed, ionized and detected using ELDI/MS, wherein analysis of the herbal toxins was completed within 30 s. This approach allows for the rapid morphological recognition of herbs and early point-of-care identification of herbal toxins for emergency management and is promising in providing important toxicological information to ensure appropriate medical treatment.


Assuntos
Serviços Médicos de Emergência , Plantas Tóxicas/química , Toxinas Biológicas/análise , Aconitina/análogos & derivados , Aconitina/análise , Flavanonas/análise , Humanos , Piridoxina/análogos & derivados , Piridoxina/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
3.
Anal Chim Acta ; 1049: 1-9, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30612639

RESUMO

A simple and cheap design for interfacing thin layer chromatography (TLC) with electrospray ionization mass spectrometry (ESI/MS) was developed to scan and characterize compounds on TLC plate. The developed TLC plate was rapidly and easily modified into two sawtooth-edged pieces that were positioned on an XYZ stage so that one of the triangular tips was pointed toward the MS inlet. A drop of methanol and high DC voltage was applied at the tip to induce ESI. After the analytes in the first tip were analyzed, the TLC piece was moved so that the second triangular tip was pointed toward the MS inlet for analysis. The process was repeated until all the triangular tips on the piece were analyzed. In this manner, the analytes, no matter visible or non-visible bands, were scanned and characterized. Since a 4.8 cm long TLC track were cut to 32 triangles on two sawtooth pieces for analysis, the spatial resolution of using the sawtooth TLC-ESI/MS for analysis is 1.5 mm/band. A mixture of dye standards and Datura metel flower extract was analyzed to demonstrate the capability of sawtooth TLC-ESI/MS on scanning and characterizing chemical compounds on the TLC plates. The limits of detection of the dye standards were between 0.25 and 2.5 ng/band. TLC bands containing alkaloids such as scopolamine and norscopolamine from the Datura metel flower extract were not visualized on the developed TLC track, but were successfully detected at different triangular tips using sawtooth TLC-ESI/MS. Based on these results, the Rf values of scopolamine and norscopolamine were determined.


Assuntos
Cromatografia em Camada Fina/métodos , Corantes/análise , Extratos Vegetais/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Cromatografia em Camada Fina/instrumentação , Datura metel/química , Técnicas Eletroquímicas/métodos , Flores/química , Limite de Detecção , Escopolamina/análise , Derivados da Escopolamina/análise
4.
Bioresour Technol ; 98(1): 232-6, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16406607

RESUMO

Investigations were carried out to evaluate the therapeutic properties of the seeds and leaves of Moringa oleifera Lam as herbal medicines. Ethanol extracts showed anti-fungal activities in vitro against dermatophytes such as Trichophyton rubrum, Trichophyton mentagrophytes, Epidermophyton floccosum, and Microsporum canis. GC-MS analysis of the chemical composition of the essential oil from leaves showed a total of 44 compounds. Isolated extracts could be of use for the future development of anti-skin disease agents.


Assuntos
Antifúngicos/farmacologia , Moringa oleifera/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Óleos de Plantas/farmacologia , Antifúngicos/química , Fungos/efeitos dos fármacos , Óleos Voláteis/química , Extratos Vegetais/química , Folhas de Planta/química , Óleos de Plantas/química , Sementes/química
5.
Surg Neurol ; 65(3): 253-60; discussion 260-1, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16488244

RESUMO

BACKGROUND: The contribution of MER to improving bilateral STN-DBS is debatable. To resolve the controversy and elucidate the role of MER in DBS, we compared the outcome of bilateral STN-DBS surgery with and without MER in parkinsonian patients. METHODS: From February 2002 to November 2002, the first 7 of 13 consecutive parkinsonian patients received STN-DBS without MER (group A), and the last 6 received STN-DBS with MER (group B). Pre- and postoperative assessments included scoring of UPDRS with video taping, and MR images. RESULTS: The mean Hoehn and Yahr stage was 3.6 in group A and 4.0 in group B. The mean follow-up was 7.4 months for group A and 5.3 months for group B. The mean coordinates of the tip of the permanent electrode relative to the mid-commissural point were x = 8.1 mm, y = 4.3 mm, and z = 5.9 mm for group A and x = 10.6 mm, y = 4.1 mm, and z = 6.9 mm for group B. When levodopa was withdrawn from group A for 12 hours at follow-up, the postoperative UPDRS total score improved by 27.6% (P = .01) and the motor score by 25.4% (P = .02); their LEDD decreased by 17.5% (P = .03). In group B, the postoperative UPDRS total score improved by 49.3% (P = .00002) and the motor score by 45.2% (P = .0004); LEDD decreased by 48.5% (P = .01). CONCLUSIONS: Although STN-DBS is a promising surgical modality for advanced parkinsonian patients, there is an inevitable learning curve associated with adopting this new procedure. Intraoperative MER is an effective way to ensure correct electrode placement in the STN. With the assistance of intraoperative MER, the outcome of STN-DBS can be improved significantly.


Assuntos
Terapia por Estimulação Elétrica , Eletroencefalografia , Imageamento por Ressonância Magnética , Microeletrodos , Transtornos Parkinsonianos/terapia , Núcleo Subtalâmico/fisiopatologia , Cirurgia Assistida por Computador , Idoso , Antiparkinsonianos/administração & dosagem , Terapia Combinada , Dominância Cerebral/fisiologia , Feminino , Seguimentos , Humanos , Levodopa/administração & dosagem , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Transtornos Parkinsonianos/fisiopatologia , Estudos Retrospectivos , Técnicas Estereotáxicas , Resultado do Tratamento
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