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1.
Cell ; 180(2): 278-295.e23, 2020 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-31978345

RESUMEN

Mutations in FAMIN cause arthritis and inflammatory bowel disease in early childhood, and a common genetic variant increases the risk for Crohn's disease and leprosy. We developed an unbiased liquid chromatography-mass spectrometry screen for enzymatic activity of this orphan protein. We report that FAMIN phosphorolytically cleaves adenosine into adenine and ribose-1-phosphate. Such activity was considered absent from eukaryotic metabolism. FAMIN and its prokaryotic orthologs additionally have adenosine deaminase, purine nucleoside phosphorylase, and S-methyl-5'-thioadenosine phosphorylase activity, hence, combine activities of the namesake enzymes of central purine metabolism. FAMIN enables in macrophages a purine nucleotide cycle (PNC) between adenosine and inosine monophosphate and adenylosuccinate, which consumes aspartate and releases fumarate in a manner involving fatty acid oxidation and ATP-citrate lyase activity. This macrophage PNC synchronizes mitochondrial activity with glycolysis by balancing electron transfer to mitochondria, thereby supporting glycolytic activity and promoting oxidative phosphorylation and mitochondrial H+ and phosphate recycling.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Adenina/metabolismo , Adenosina/metabolismo , Adenosina Desaminasa/metabolismo , Cromatografía Liquida/métodos , Células HEK293 , Células Hep G2 , Humanos , Péptidos y Proteínas de Señalización Intracelular/fisiología , Espectrometría de Masas/métodos , Enzimas Multifuncionales/genética , Fosforilación , Proteínas/genética , Nucleótidos de Purina/metabolismo , Purinas/metabolismo
2.
J Chromatogr A ; 1610: 460544, 2020 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-31564561

RESUMEN

Estimation of the properties of mesoporous aluminosilicates in various environments is important when assessing their sorption capacity. Using inverse liquid chromatography (ILC), Hansen solubility parameters (HSP) and linear free energy relationship (LFER) parameters were calculated to determine the properties of aluminosilicates in a protic and an aprotic system, using water and acetonitrile as the mobile phase, respectively. The calculated Hansen parameters, reflecting the ability of the material under investigation to different types of intermolecular interactions, slightly differ depending on the mobile phase used. It was found that in the presence of water the surface of aluminosilicates shows a weaker ability to interact, as evidenced by negative or near-zero e, s, a, b, v coefficients. Additionally, it was found that the Si/Al ratio in aluminosilicates structure has little effect on the determined parameters.


Asunto(s)
Silicatos de Aluminio/análisis , Silicatos de Aluminio/química , Cromatografía Liquida/métodos , Solubilidad , Agua
3.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1081-1082: 76-86, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29518720

RESUMEN

Eclipta alba (Bhringraj) in ayurveda has been widely used as a traditional medicine for its multi-therapeutic properties for ages. Luteolin (LTL), wedelolactone (WDL) and apigenin (APG) are the three main bioactive phytochemicals present in Eclipta alba extract. However there was a lack of sensitive bioanalytical method for the pharmacokinetics of these free compounds in plasma which majorly contributes for their activities after oral administration of Eclipta alba. The present study aims to develop a sensitive, rapid and reliable liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the simultaneous estimation of mice plasma concentrations of LTL, WDL and APG using quercetin as an internal standard for the pharmacokinetic analysis. Analytes were separated on Phenomenex Luna C18 (150 × 4.6 mm, 3.0 µm) column with mobile phase containing methanol: acetonitrile (90: 10, v/v) and 0.1% formic acid in 10 mM ammonium formate buffer in the ratio of 70: 30 (v/v) in isocratic mode. Liquid-liquid extraction was optimized using Hansen solubility parameters and diethyl ether finalized as an extraction solvent for the recovery ranging from 61 to 76% for all analytes in mice plasma. The validated method has an accuracy and precision over the linearity range of 0.1-200 ng/mL with a correlation coefficient (r2) of ≥0.997. The intra and inter-day assay accuracy was between 98.17 and 107% and 95.83-107.89% respectively and the intra and inter day assay precision ranged from 0.37-6.05% and 1.85-10.76%, respectively for all the analytes. This validated method can be used for future clinical investigation studies of Eclipta alba extracts.


Asunto(s)
Apigenina/sangre , Cumarinas/sangre , Eclipta/química , Extracción Líquido-Líquido/métodos , Luteolina/sangre , Extractos Vegetales/farmacocinética , Animales , Apigenina/química , Apigenina/aislamiento & purificación , Apigenina/farmacocinética , Cloroformo , Cromatografía Liquida/métodos , Cumarinas/química , Cumarinas/aislamiento & purificación , Cumarinas/farmacocinética , Límite de Detección , Modelos Lineales , Luteolina/química , Luteolina/aislamiento & purificación , Luteolina/farmacocinética , Ratones , Extractos Vegetales/química , Reproducibilidad de los Resultados , Solubilidad , Espectrometría de Masas en Tándem/métodos
4.
Ther Drug Monit ; 31(5): 602-3, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19704404

RESUMEN

Thalidomide is used for the acute treatment and suppression of the cutaneous manifestations of erythema nodosum leprosum (ENL). In this study, comparisons were made regarding the plasma concentrations of thalidomide in patients with ENL on the course or after leprosy therapy in a prospective clinical trial. Thalidomide concentrations were measured by liquid chromatography on days 1, 3, and 14 of treatment. After 100 mg/d, the thalidomide concentrations ranged from 0.82 to 1.03 and 0.43 to 0.80 microg/mL, on the course or after leprosy therapy, respectively. No differences were observed in thalidomide concentrations between and within the groups. Our results suggested that leprosy multidrug therapy does not seem to affect the plasma concentrations of thalidomide in patients with ENL.


Asunto(s)
Eritema Nudoso/sangre , Leprostáticos/sangre , Lepra Lepromatosa/sangre , Talidomida/sangre , Adulto , Cromatografía Liquida/métodos , Eritema Nudoso/tratamiento farmacológico , Humanos , Leprostáticos/uso terapéutico , Lepra Lepromatosa/tratamiento farmacológico , Masculino , Tasa de Depuración Metabólica , Talidomida/metabolismo , Vasculitis/inducido químicamente , Vasculitis/tratamiento farmacológico , Adulto Joven
5.
Int J Food Microbiol ; 94(1): 55-66, 2004 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-15172485

RESUMEN

The proteolytic changes taking place in dry-cured hams lead to increases in free amino acids. Such free amino acids not only contribute to flavour, but also serve as precursors of volatile compounds. Several months of ripening time are required to allow the particular flavour to develop. The fungal population allowed to grow on the surface of some types of dry-cured could play a key role on proteolysis, as it has been shown for dry-cured sausages. The purpose of this work was to study the possible contribution of fungi to proteolysis in dry-cured ham. For this, a strain each of non-toxigenic Penicillium chrysogenum (Pg222) and Debaryomyces hansenii (Dh345), selected for their proteolytic activity on myofibrillar proteins, were inoculated as starter cultures. Changes in the high ionic strength-soluble proteins of an external muscle (adductor) revealed in only 6 months higher proteolysis in the inoculated hams when compared to non-inoculated control hams. Proteolytic strains among the wild fungal population on non-inoculated control hams prevented from obtaining similar differences at the end of processing. However, inoculation with Pg222 and Dh345 led to higher levels for most free amino acids at the external muscle in fully dry-cured hams. In addition, the concentration for some of the more polar free amino acids (i.e. Asp, Glu, Ser and Gln) in inoculated hams was higher at external than at internal (biceps femoris) muscles. These promising results deserve further studies to know the impact of a selected fungal population on the volatile compounds and sensory properties of dry-cured ham.


Asunto(s)
Aminoácidos/análisis , Manipulación de Alimentos/métodos , Microbiología de Alimentos , Productos de la Carne/microbiología , Penicillium chrysogenum/metabolismo , Saccharomycetales/metabolismo , Animales , Cromatografía Liquida/métodos , Fermentación , Porcinos , Volatilización
6.
RBCF, Rev. bras. ciênc. farm. (Impr.) ; 36(2): 220-5, jul.-dez. 2000. graf
Artículo en Portugués | LILACS | ID: lil-289826

RESUMEN

A dapsona (4,4-diaminodifenilsulfona), quimioterápico bacteriostático utilizado no tratamento da hanseníase, vem sendo associada a intercorrências clínicas, principalmente devido à sua hemotoxicidade caracterizada por metemoglobinemia e anemia hemolítica. A N-hidroxilação, uma das principais vias de biotransformação da dapsona, vem sendo associada constantemente a quadros de metemoglobinemia decorrentes de sua utilização. Com o objetivo de verificar-se a inibição reversível da via de bioativação toxicológica, sem alterar as vias de destoxificação do composto, a acetilação citosólica, a cimetidina foi administrada concomitantemente à dapsona em ratos machos Wistar, com peso variando entre 200 e 220 g, divididos em 8 grupos (n=6 por grupo), em estudo de dose única...


Asunto(s)
Animales , Ratas , Anemia Hemolítica/terapia , Cimetidina/administración & dosificación , Dapsona/farmacocinética , Lepra , Metahemoglobinemia/metabolismo , Cromatografía Liquida/métodos , Espectrofotometría , Interpretación Estadística de Datos
7.
Ribeirao Preto; s.n; 2000. 114 p. ilus, tab, graf.
Tesis en Portugués | LILACS, Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1236692

RESUMEN

Dapsona, farmaco bacteriostatico utilizado no tratamento da hanseniase, vem sendo associado a intercorrencias clinicas, principalmente devido a sua hemotoxicidade. A N-hidroxilacao, uma das principais vias de biotransformacao da dapsona vem sendo associada constantemente a quadros de metemoglobinemia decorrentes do uso da dapsona. Com objetivo de se verificar a inibicao reversivel desta via de bioativacao toxicologica, sem alterar os caminhos de detoxificacao do farmaco, a aceltilacao citosolica, a cimetidina, ranitidina e famotidina foram administradas concomitantemente a dapsona em ratos machos Wistar, com peso variando entre 200 e 250g divididos em 30 grupos (n=6), em estudo de doses unicas e multiplas. Apos as administracoes, os ratos foram submetidos a coleta de sangue


Asunto(s)
Anemia Hemolítica/terapia , Interpretación Estadística de Datos , Cimetidina/administración & dosificación , Cromatografía Liquida/métodos , Dapsona/farmacocinética , Lepra , Metahemoglobinemia , Toxicología
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