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1.
Genes (Basel) ; 12(9)2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34573312

RESUMO

Ufmylation is a relatively newly discovered type of post-translational modification when the ubiquitin-fold modifier 1 (UFM1) protein is covalently attached to its target proteins in a three-step enzymatic reaction involving an E1 activating enzyme (UBA5), E2 conjugating enzyme (UFC1), and E3 ligase enzyme (UFL1). The process of ufmylation is essential for normal brain development and function in humans. Mutations in the UFM1 gene are associated with Hypomyelinating leukodystrophy type 14, presenting with global developmental delay, failure to thrive, progressive microcephaly, refractive epilepsy, and hypomyelination, with atrophy of the basal ganglia and cerebellum phenotypes. The c.-155_-153delTCA deletion in the promoter region of UFM1 is considered to be a founding mutation in the Roma population. Here we present four index patients with homozygous UFM1:c.-155_-153delTCA mutation detected by next-generation sequencing (whole genome/exome sequencing) or Sanger sequencing. This mutation may be more common in the Roma population than previously estimated, and the targeted testing of the UFM1:c.-155_-153delTCA mutation may have an indication in cases of hypomyelination and neurodegenerative clinical course in pediatric patients of Roma descent.


Assuntos
Enzimas de Conjugação de Ubiquitina
2.
Molecules ; 24(15)2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31387338

RESUMO

BACKGROUND: A low dose of capsaicin and its natural homologs and analogs (capsaicinoids) have shown to prevent development of gastric mucosal damage of alcohol and non-steroid anti-inflammatory drugs. Based on this experimental observation, a drug development program has been initiated to develop per os applicable capsaicin containing drugs to eliminate gastrointestinal damage caused by non-steroid anti-inflammatory drugs. METHODS: As a part of this program, a sensitive and selective reverse-phase high-performance liquid chromatography-based method with fluorescence detection has been developed for quantification of capsaicin and dihydrocapsaicin in experimental dog's plasma. RESULTS: The method was evaluated for a number of validation characteristics (selectivity, repeatability, and intermediate precision, LOD, LOQ, and calibration range). The limit of detection (LOD) was 2 ng/mL and the limit of quantification (LOQ) was 10 ng/mL for both capsaicin and dihydrocapsaicin. The method was used for analysis of capsaicin and dihydrocapsaicin in the plasma samples obtained after per os administration of low doses (0.1, 0.3, and 0.9 mg/kg bw) of Capsaicin Natural (USP 29) to the experimental animals. CONCLUSIONS: The obtained results indicated that the administered capsaicinoids did not reach the general circulation.


Assuntos
Capsaicina/química , Capsaicina/farmacologia , Substâncias Protetoras/química , Substâncias Protetoras/farmacologia , Animais , Capsaicina/toxicidade , Cromatografia Líquida de Alta Pressão , Cães , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Limite de Detecção , Estrutura Molecular , Reprodutibilidade dos Testes , Estômago/efeitos dos fármacos , Toxicocinética
3.
J Pharm Biomed Anal ; 103: 59-66, 2015 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25462121

RESUMO

A sensitive and selective reverse-phase high performance liquid chromatographic method with fluorescence detection has been developed for determination of capsaicin (8-methyl-N-vanillyl-(trans)-6-nonenamid) and dihydrocapsaicin (8-methyl-N-vanillylnonanamide) in samples generated in rat small intestine luminal perfusion experiments. The experiments were designed to study the biotransformation of capsaicinoids in the small intestine in the rat. The chromatographic separation was performed at room temperature on a ZORBAX Eclipse(®) XDB-C8 column using isocratic elution with a mobile phase consisting 0.05M orthophosphoric acid solution and acetonitrile (60:40, v/v; pH 3.0) with a flow rate of 1.5mL/min. Fluorescence detection was performed at excitation and emission wavelengths of 230 and 323nm, respectively. The method was evaluated for a number of validation characteristics (accuracy, repeatability and intermediate precision, limit of detection, limit of quantification and calibration range). The limit of detection (LOD) was 50ng/mL and the limit of quantification (LOQ) was 100ng/mL for both capsaicin and dihydrocapsaicin reference standards dissolved in blank perfusate. The method was successfully applied for investigation of intestinal absorption of capsaicin and dihydrocapsaicin while 30µg/mL standardized Capsicum extract - containing capsaicin and dihydrocapsaicin - was luminally perfused for a 90min period. The structure of the glucuronide metabolites of capsaicin and dihydrocapsaicin appeared in the perfusate was identified by mass spectrometry.


Assuntos
Capsaicina/análogos & derivados , Capsaicina/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Absorção Intestinal , Espectrometria de Fluorescência/métodos , Animais , Área Sob a Curva , Calibragem , Capsaicina/metabolismo , Limite de Detecção , Masculino , Ratos , Ratos Wistar , Padrões de Referência , Reprodutibilidade dos Testes
4.
J Chromatogr Sci ; 53(1): 16-23, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24557717

RESUMO

A reverse-phase high-performance liquid chromatography method was developed to quantify capsaicin (trans-8-methyl-N-vanillyl-6-nonenamid), dihydrocapsaicin (8-methyl-N-vanillylnonanamide) and the main capsaicinoid contents of Capsicum extracts. The chromatographic separation was carried out on a C8 column using isocratic mobile phase consisting of 40% (v/v) acetonitrile and 60% (v/v) orthophosphoric acid solution with flow rate of 1.5 mL/min. The concentration of the eluting compounds was monitored by a diode-array detector at wavelength of 281 nm. The method was evaluated for number of validation characteristics (selectivity, accuracy (confidence intervals <1%), repeatability and intermediate precision (RSD% < 2.5%), limit of detection (LOD), limit of quantification (LOQ) and calibration range). The LOD was 0.25 µg/mL and the LOQ was 0.5 µg/mL. Using methanolic solutions of United States Pharmacopoeia (USP) Capsaicin and Dihydrocapsaicin Reference Standards, the method was linear over the concentration range 0.0005-0.5000 mg/mL for both capsaicinoids. The method was applied to qualify capsaicinoid content of two industrial capsicum extracts according to the USP 29.


Assuntos
Capsicum/química , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/análise , Capsaicina/análogos & derivados , Capsaicina/análise , Cromatografia Líquida de Alta Pressão/normas , Limite de Detecção , Padrões de Referência
5.
Artigo em Inglês | MEDLINE | ID: mdl-19939951

RESUMO

Viscum album preparations are aqueous mistletoe plant extracts used in complementary and alternative medicine as immunomodulators in cancer therapy. However, evidence of immunological efficacy of mistletoe extracts (MEs) used in clinical trials is often lacking. Mechanisms involved in anti-tumor properties of ME and mistletoe lectins (MLs) modify both innate and adaptive immune systems, according to animal model experiments. In the background of these effects, a selective binding of ML on CD75 ganglioside receptors of interleukin 12 (IL-12)-producing macrophages or dendritic cells can play an important role. Immunological effects of ME correlate with their lectin activity, showing a bell-shaped dose-response curve of efficacy. Therefore, a correct determination of MLs for the standardization of commercial ME is essential. However, plant MLs exhibit heterogeneity, which most likely results from post-translational processing. In addition, amino acid analysis of ML has revealed numerous conservative substitutions along their amino acid sequence. Consequently, ML research needs new perspectives, and the advantages and disadvantages of purified and biologically better defined ML preparations are also discussed in this article.

6.
Acta Pharm Hung ; 76(3): 140-4, 2006.
Artigo em Húngaro | MEDLINE | ID: mdl-17094661

RESUMO

The authors examined the possible peroxyl radical scavanger effect of some non-steroidal antiinflammatory drugs and isomeric dihidroxy benzoic acids by means of the test based on 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-initiated degradation of crocin. The method is based on spectrophotometric determination of crocin, of which rate of AAPH-initiated degradation can be decreased in the presence of antioxidants with peroxyl radical scavanger activity. The authors studied the crocin degradation-inhibitory effect of phenacetin, paracetamol (acetaminophen), indomethacin, ibuprofen, diclofenac sodium, salicylic acid, salicylamide as well as the 2,3-, 2,4-, 2,5- and 3,4-dihydroxy substituted benzoic acids in 200 microM concentration. In the 60 minute studies the 2,3-, 2,5- and 3,4-dihydroxy benzoic acids proved to show the most effective degradation inhibitory effect. The results draw attention to the different antioxidant activity of salicylic acid and its hydroxylated metabolites (2,3- and 2,5-dihydroxy benzoic acids) formed under physiological conditions.


Assuntos
Amidinas/química , Anti-Inflamatórios não Esteroides/química , Carotenoides/química , Sequestradores de Radicais Livres/química , Salicilatos/química , Acetaminofen/química , Fenacetina/química
7.
J Biochem Biophys Methods ; 69(1-2): 143-50, 2006 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-16814866

RESUMO

The effect on mitochondrial outer membrane of 4-hydroxychalcone (1), the cyclic chalcone analogues E-2-(4'-hydroxybenzylidene)-1-indanone (2a) and E-2-(4'-hydroxybenzylidene)-1-tetralone (2b), the dihydrochalcones phloretin (3a) and phloridzin (3b), the flavanones naringenin (4a) and naringin (4b), and the flavonol quercetin (5) was investigated by fluorescence spectroscopy. Excitation and emission fluorescence spectra of each flavonoid and synthetic analogue were recorded in respiration medium containing 1 mM succinate. Initial interaction of the compounds with the outer mitochondrial membrane was investigated by recording their fluorescence polarization in the presence of rat liver mitochondria. Most of the compounds displayed an elevated fluorescence polarization on mixing with mitochondria at the zero time point. During the investigated 20 min period the initial fluorescence polarization values remained constant (1, 2a), or a gradual depression of the measured polarization values could be observed (2b, 3a, 4b, 5). In the case of naringenin (4a), however, similar to the previously investigated seven-membered cyclic chalcone analogue E-2-(4 -methoxybenzylidene)-1-benzosuberone, a slight, continuous increase of fluorescence polarization could be detected during the 20 min experiment. Phloridzin (3b) showed an increased fluorescence polarization in first 10 min, which was slightly depressed by the 20 min time point.


Assuntos
Chalconas/farmacologia , Flavonoides/farmacologia , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Animais , Chalconas/química , Flavanonas/farmacologia , Flavonoides/química , Polarização de Fluorescência , Técnicas In Vitro , Masculino , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Florizina/farmacologia , Ratos , Ratos Wistar , Espectrometria de Fluorescência , Espectrofotometria , Espectrofotometria Ultravioleta
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