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1.
Korean J Parasitol ; 55(4): 409-416, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28877572

RESUMO

The high prevalence of pediculosis capitis, commonly known as head lice (Pediculus humanus capitis) infestation, has led to the preparation of a community-based pediculicidal ointment, which is made of common household items and the extract of Tinospora crispa stem. The present study aimed to evaluate the safety, efficacy, and physicochemical characteristics of the T. crispa pediculicidal ointment. The physicochemical properties of the ointment were characterized, and safety was determined using acute dermal irritation test (OECD 404), while the efficacy was assessed using an in vitro pediculicidal assay. Furthermore, the chemical compounds present in T. crispa were identified using liquid-liquid extraction followed by ultra-performance liquid chromatography quadruple time-of-flight mass spectrometric (UPLC-qTOF/MS) analysis. The community-based ointment formulation was light yellow in color, homogeneous, smooth, with distinct aromatic odor and pH of 6.92±0.09. It has spreadability value of 15.04±0.98 g·cm/sec and has thixotropic behavior. It was also found to be non-irritant, with a primary irritation index value of 0.15. Moreover, it was comparable to the pediculicidal activity of the positive control Kwell®, a commercially available 1% permethrin shampoo (P>0.05), and was significantly different to the activity of the negative control ointment, a mixture of palm oil and candle wax (P<0.05). These findings suggested that the community-based T. crispa pediculicidal ointment is safe and effective, having acceptable physicochemical characteristics. Its activity can be attributed to the presence of compounds moupinamide and physalin I.


Assuntos
Composição de Medicamentos , Infestações por Piolhos/tratamento farmacológico , Infestações por Piolhos/parasitologia , Pediculus , Fitoterapia , Extratos Vegetais , Tinospora/química , Animais , Fenômenos Químicos , Ácidos Cumáricos/análise , Pomadas , Pediculus/efeitos dos fármacos , Praguicidas , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Segurança , Secoesteroides/análise , Testes de Irritação da Pele , Tiramina/análogos & derivados , Tiramina/análise
2.
Biochem Biophys Res Commun ; 446(3): 702-8, 2014 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-24412245

RESUMO

There is rising interest in non-enzymatic cholesterol oxidation because the resulting oxysterols have biological activity and can be used as non-invasive markers of oxidative stress in vivo. The preferential site of oxidation of cholesterol by highly reactive species is at C7 having a relatively weak carbon-hydrogen bond. Cholesterol autoxidation is known to proceed via two distinct pathways, a free radical pathway driven by a chain reaction mechanism (type I autoxidation) and a non-free radical pathway (type II autoxidation). Oxysterols arising from type II autoxidation of cholesterol have no enzymatic correlates, and singlet oxygen ((1)ΔgO2) and ozone (O3) are the non-radical molecules involved in the mechanism. Four primary derivatives are possible in the reaction of cholesterol with singlet oxygen via ene addition and the formation of 5α-, 5ß-, 6α- and 6ß-hydroxycholesterol preceded by their respective hydroperoxyde intermediates. The reaction of ozone with cholesterol is very fast and gives rise to a complex array of oxysterols. The site of the initial ozone reaction is at the Δ5,6 -double bond and yields 1,2,3-trioxolane, a compound that rapidly decomposes into a series of unstable intermediates and end products. The downstream product 3ß-hydroxy-5-oxo-5,6-secocholestan-6-al (sec-A, also called 5,6-secosterol), resulting from cleavage of the B ring, and its aldolization product (sec-B) have been proposed as a specific marker of ozone-associated tissue damage and ozone production in vivo. The relevance of specific ozone-modified cholesterol products is, however, hampered by the fact sec-A and sec-B can also arise from singlet oxygen via Hock cleavage of 5α-hydroperoxycholesterol or via a dioxietane intermediate. Whatever the mechanism may be, sec-A and sec-B have no enzymatic route of production in vivo and are reportedly bioactive, rendering them attractive biomarkers to elucidate oxidative stress-associated pathophysiological pathways and to develop pharmacological agents.


Assuntos
Colestanonas/metabolismo , Colesterol/metabolismo , Inflamação/metabolismo , Ozônio , Secoesteroides/metabolismo , Biomarcadores/análise , Técnicas de Química Analítica , Colestanonas/análise , Radicais Livres , Humanos , Oxirredução , Estresse Oxidativo , Ozônio/química , Ozônio/metabolismo , Secoesteroides/análise , Oxigênio Singlete/química , Oxigênio Singlete/metabolismo
3.
Phytochem Anal ; 23(4): 337-44, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21997776

RESUMO

INTRODUCTION: Chinese lantern is the calyx or calyx-with-fruit of the plant Physalis alkekengi .var. franchetii (Solanaceae), and is potential material for the food and pharmaceutical industries. Physalins are the most active and representative secondary metabolites of Chinese lantern. A separation and quantification method based on UPLC-ESI-MS/MS was developed for the quantitative analysis of five active physalins. The transformation products were also detected and identified for the first time. OBJECTIVE: To establish a LC-MS/MS method to quantify five physalins in Chinese lantern for the purpose of quality control, and to identify the transformation products of 4,7-didehydrophysalin B. METHODOLOGY: The separation was carried out on an Acquity UPLC BEH Shield RP C18-column with water and acetonitrile as the mobile phase under gradient conditions. ESI-MS/MS was used as the detector to quantify the five physalins. The transformation products of 4,7-didehydroneophysalin B were detected by UPLC-PDA-ESI-MS/MS and identified through comparing their HRMS and MS² ion fragmentations with corresponding references. RESULTS: All the compounds showed good linearity (R² > 0.998). The recoveries, measured at three concentration levels, varied from 98.8 to 101.4% with RSDs < 4.5%. The total contents of the five physalins in Chinese lantern varied significantly. Three transformation products of 4,7-didehydroneophysalin B were detected and tentatively identified. CONCLUSION: The present study developed a highly effective analytical method for the quality control of Chinese lantern, and it could provide comprehensive information for quality evaluation and new drug development of Chinese lantern.


Assuntos
Physalis/metabolismo , Secoesteroides/análise , Secoesteroides/metabolismo , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Calibragem , Cromatografia Líquida/métodos , Cromatografia Líquida/normas , Limite de Detecção , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Controle de Qualidade , Padrões de Referência , Secoesteroides/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray/normas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/normas
4.
J Chromatogr B Analyt Technol Biomed Life Sci ; 879(26): 2802-8, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21871845

RESUMO

Cholesterol ozonolysis products, 3ß-hydroxy-5-oxo-5,6-secocholestan-6-al (secosterol-A) and its aldolization product 3ß-hydroxy-5ß-hydroxy-B-norcholestane-6ß-carboxaldehyde (secosterol-B) have been found in atherosclerosis plaques and the brain tissues of Alzheimer's disease patients, implicating them in the pathogenesis of cardiovascular and neurodegenerative diseases. We have recently reported that when cholesterol is oxidized with an ozone-like oxidant generated by activated mouse neutrophils, secosterol-A is generated which is then converted to secosterol-B by an aldol reaction. To investigate further pathophysiological roles of secosterols, we have developed a highly sensitive method to detect secosterol-A and -B as derivatives with 2-hydrazino-1-methylpyridine (HMP) by LC-ESI-MS/MS. The limits of detection for the HMP derivatives of secosterol-A and secosterol-B were 0.05 and 0.01fmol, respectively, which were approximately 400 and 2000 times better than those for underivatized secosterol-A and -B. We also developed a highly reproducible and accurate method to extract, purify and derivatize secosterol in small volumes of biological specimens. Using this method, we determined the levels of secosterol-A and -B as 1.4 ± 0.7 and 4.3 ± 0.8 nM, respectively, in the plasma of normal C57BL/6 mice, and in the range of 10.4 ± 16.3 to 40.7 ± 20.1 pmol/g and 110.9 ± 10.6 to 161.5 ± 56.3 pmol/g, respectively, in the brain, liver and lung tissues.


Assuntos
Colesterol/metabolismo , Cromatografia Líquida/métodos , Hidrazinas/química , Ozônio/química , Piridinas/química , Secoesteroides/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Colesterol/análogos & derivados , Colesterol/análise , Colesterol/sangue , Modelos Lineares , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Reprodutibilidade dos Testes , Secoesteroides/sangue , Secoesteroides/química , Secoesteroides/metabolismo , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem , Distribuição Tecidual
5.
J Chromatogr B Analyt Technol Biomed Life Sci ; 879(5-6): 443-8, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21269892

RESUMO

Physalin D is an important constituent of some traditional Chinese medicines, and has several known bioactivities. An UPLC-MS/MS method for the determination of physalin D in rat plasma and tissues was developed and the pharmacokinetic and tissue distribution characteristics of physalin D after intravenous administrations were investigated. The bio-samples were prepared by a simple protein precipitation, and the separation of physalin D was achieved on a UPLC HSS T3 column with a mobile phase consisting of methanol/acetonitrile (70:30, v/v) and water (containing 0.1% formic acid and 10 mM ammonium acetate) at a flow rate of 0.3 mL/min. The MS/MS detection was carried out by monitoring the fragmentation of m/z 544.9→508.8 for physalin D and m/z 286.7→152.8 for luteolin (internal standard; IS) on a triple-quadrupole mass spectrometer. The total run time was only 3.6 min. The analyte showed good linearity over a wide concentration range (R(2)>0.995) and its lower limit of quantification was 2 ng/mL. The pharmacokinetic study found that physalin D was distributed and eliminated rapidly in rats (t(1/2)<10 min). Tissue distribution showed the highest level was observed in kidney, then in liver, but no physalin D was detected in brain, which indicated that kidney was the major distribution tissue for physalin D in rats and that physalin D does not cross the blood-brain barrier.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Secoesteroides/sangue , Espectrometria de Massas em Tandem/métodos , Animais , Estabilidade de Medicamentos , Rim/química , Luteolina , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Secoesteroides/análise , Secoesteroides/farmacocinética , Distribuição Tecidual
6.
Pharm Biol ; 48(2): 142-50, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20645830

RESUMO

Physalis alkekengi L. (Solanaceae) is a popular plant in traditional European and Chinese folk medicine, and it has been reported to have many ethnopharmacological properties including antifungal, anti-cough, anti-inflammatory, analgesic, and febricide activities. Some active components from Physalis species have been investigated. However, no antimicrobial activity studies on extracts and physalins of P. alkekengi have been carried out. In this study, we attempted to identify the possible antimicrobial activities of the methanol extract from aerial parts of P. alkekengi and the dichloromethane extract from calyces of the plant. The extracts were tested against five Gram-positive and five Gram-negative bacteria and five Candida species by using disk diffusion and broth microdilution methods. The extracts were fractionated to isolate physalins using chromatographic techniques, and physalin D was isolated from the extracts. The structure of the compound was elucidated on the basis of (1)H-NMR spectroscopic study, and confirmed by comparison with a reference sample and literature data. Results indicated that all the extracts and physalin D were characterized by antibacterial action, especially against Gram-positive bacteria, with MIC values between 32 and 128 microg/mL. The methanol extract had moderate activity against fungi at MICs ranging from 128 to 512 microg/mL, but the dichloromethane extract and physalin D had low activity against fungi at MICs ranging from 256 to 512 microg/mL. Additionally, the antioxidant activity of physalin D was evaluated by qualitative DPPH (1,1-diphenyl-2-picrylhydrazyl) radical and TBA (thiobarbituric acid) assays. Physalin D showed low antioxidant activity with an IC(50) value of >or= 10 +/- 2.1.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Medicina Tradicional , Physalis/química , Componentes Aéreos da Planta/química , Extratos Vegetais/farmacologia , Secoesteroides/farmacologia , Anti-Infecciosos/análise , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/química , Candida/efeitos dos fármacos , Linhagem Celular , Flores/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Fitoterapia , Picratos/química , Secoesteroides/análise , Secoesteroides/química , Secoesteroides/isolamento & purificação , Substâncias Reativas com Ácido Tiobarbitúrico/análise
7.
Steroids ; 74(2): 218-28, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19028513

RESUMO

Pregna-5,7-dienes and their hydroxylated derivatives can be formed in vivo when there is a deficiency in 7-dehydrocholesterol (7-DHC) Delta-reductase function, e.g., Smith-Lemli-Opitz syndrome (SLOS). Ultraviolet B (UVB) radiation induces photoconversion of 7-DHC to vitamin D3, lumisterol3 and tachysterol3. Two epimers (20R and 20S) of pregna-5,7-diene-3beta,17alpha,20-triol (4R and 4S, respectively) were synthesized and their UVB photo-conversion products identified as corresponding 9,10-secosteroids with vitamin D-like and tachysterol-like structures, and 5,7-dienes with inverted configuration at C-9 and C-10 (lumisterol-like). The number and character of the products and the dynamics of the process were dependent on the UVB dose. At high UVB doses, the formation of multiple oxidized derivatives of the primary products, and the formation of 5,7,9(11)-triene, were observed. The production of vitamin D-like, tachysterol-like and lumisterol-like derivatives was also observed in human skin treated with 4R and 4S, and subjected to UV irradiation, as shown by RP-HPLC. Newly synthesized compounds inhibited melanoma growth in dose dependent manner, and some of them showed equal or higher potency than 1,25(OH)2D3. In summary, we have characterized for the first time the products of UV induced conversion of pregna-5,7-diene-3beta,17alpha,20-triols and documented that the newly synthesized compounds have antiproliferative properties against melanoma cells.


Assuntos
Melanoma/metabolismo , Melanoma/patologia , Fotólise/efeitos da radiação , Pregnadienos/química , Pregnadienos/farmacologia , Pregnadienotrióis/química , Pregnadienotrióis/síntese química , Pregnadienotrióis/farmacologia , Acetilação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Pregnadienos/síntese química , Pregnadienos/metabolismo , Pregnadienotrióis/metabolismo , Secoesteroides/análise , Secoesteroides/química , Pele/metabolismo , Pele/efeitos da radiação , Estereoisomerismo , Raios Ultravioleta
8.
J Pharm Biomed Anal ; 9(10-12): 1095-105, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1822179

RESUMO

Some underivatized steroids when injected onto conventional packed columns for gas-liquid chromatography underwent varying degrees of dehydration. This problem was traced to the presence of small pieces of broken glass on the top of the column at the point of injection. This observation provoked an examination of the effect of pre-column dehydration on a number of different types of steroids. Powdered aluminium was placed in the injection liner of a Hewlett-Packard gas chromatograph fitted with an HP1 capillary column connected to a mass selective detector, and injections were made using a new high temperature septumless injection system at temperatures between 200 and 400 degrees C. 5 alpha-androstan-3 alpha-ol, a simple monofunctional C19 steroid chosen as a model to establish optimum conditions, underwent dehydration at injection temperatures greater than 250 degrees C and the product reached a maximum at 400 degrees C when no unchanged steroid was present. Monohydroxylated androgens and oestrogens underwent dehydration at 400 degrees C producing products whose mass spectra indicated they were monenes, although the position of the double bond could not be assigned. Polyfunctional androgens and oestrogens and corticosteroids underwent complex changes producing a number of products some of whose structures could not be determined. The dehydration products had the advantage that they had relatively intense high mass ions and for suitable steroids this might provide enhanced sensitivity of detection during mass fragmentography. In such cases dehydration was reproducible and straight line standard curves were obtained. C27 and C28 secosteroids (vitamins D2 and D3) and some of their metabolites (e.g. 25-hydroxyvitamin D) underwent efficient dehydration, again producing products with intense molecular ions. In the case of 24,25-dihydroxyvitamin D3 and 25,26-dihydroxyvitamin D3, dehydration produced different products which were easily resolved in the chromatographic system used. Dehydration of vitamin D metabolites eliminates the need for derivatization and gives enhanced sensitivity of measurement by gas chromatography-mass spectrometry.


Assuntos
Hormônios/análise , Esteroides/análise , Androgênios/análise , Cromatografia Gasosa , Dessecação , Estrogênios/análise , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Secoesteroides/análise , Temperatura
9.
Steroids ; 48(5-6): 439-50, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3445293

RESUMO

A mutant of the efficient bile acid-utilizing Pseudomonas putida ATCC 31752 was found to accumulate three major catabolites on aerobic growth on cholic acid. One of these catabolites was isolated and identified as 3,4,7,12 beta-tetrahydroxy-9,10-seco-1,3,5(10)-androstatriene-9,17-dione (2). This is the first catecholic 9,10-secosteroid isolated from the microbial degradation of bile acids or sterols and confirms the role of such secosteroids in the microbial degradative pathway for steroids.


Assuntos
Androstatrienos/metabolismo , Ácidos Cólicos/metabolismo , Pseudomonas/metabolismo , Secoesteroides/metabolismo , Aerobiose , Androstatrienos/análise , Ácido Cólico , Cromatografia em Gel , Fermentação , Espectroscopia de Ressonância Magnética , Secoesteroides/análise , Espectrofotometria Ultravioleta
10.
Biomed Mass Spectrom ; 4(6): 376-80, 1977 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-597588

RESUMO

The fragmentation processes occurring in various 9alpha-hydroxy steroids upon electron ionization have been studied. The mechanisms proposed for the formation of the prominent ions in these spectra have been confirmed with the aid of deuterium labelling, measurements on metastable ion decompositions, low eV spectra and high resolution mass measurements. The fragmentation of the corresponding 9-oxo-9,10-seco steroids, which shows analogy to that of the 9alpha-hydroxy compounds in many respects, has also been discussed.


Assuntos
Hidroxiesteroides/análise , Espectrometria de Massas , Secoesteroides/análise
11.
J Assoc Off Anal Chem ; 60(5): 989-92, 1977 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-893337

RESUMO

The reaction with maleic anhydride yielding Diels-Alder adducts is used to distinguish vitamin D isomers. Treatment at 100 degrees C for 3 hr eliminates the fast-reacting (tachysterol and trans-vitamin D) and slow-reacting (cis-vitamin D and previtamin D) isomers. However, isotachysterol is not eliminated. The procedure has been incorporated as a confirmation test for isotachysterol in the official final action method for the determination of vitamin D in concentrates, 43.B14-43.B24.


Assuntos
Secoesteroides/análise , Esteróis/análise , Vitamina D/análise , Ergosterol/análogos & derivados , Gorduras , Isomerismo , Métodos , Conformação Molecular , Solubilidade , Espectrofotometria
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