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1.
J Ethnopharmacol ; 279: 114393, 2021 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-34229058

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Tagetes erecta L., known as marigold, belongs to the Asteraceae family and is mainly found in South America. Despite reports that T. erecta flowers are used in folk medicine to treat cardiovascular and renal diseases, there is no study regarding its diuretic effect. AIM: This study aimed to evaluate the chemical composition and the diuretic efficacy of the hydroethanolic extract from T. erecta (HETE) in normotensive (NTR) and hypertensive (SHR) rats. MATERIAL AND METHODS: The HETE was analyzed by liquid chromatography coupled to diode array detector and mass spectrometry (LC-DAD-MS). Female and male NTR and SHR received the treatment with vehicle, HETE (0.01 mg/kg, 0.1 mg/kg, and 1 mg/kg) or hydrochlorothiazide (HCTZ; 5 mg/kg) orally. The urinary parameters were measured at the end of the 8-h experiment. RESULTS: From HETE, saccharides and triterpenes were the main annotated compounds, such as erythrodiol and ß-amyrin. The urine volume was significantly increased in the groups treated with HETE, in both male and female NTR and SHR rats, compared to the respective vehicle-treated groups. Regarding electrolytes elimination, the treatment with HETE did not reveal significant changes in the urine levels of K+ or Cl-, but it showed a natriuretic and Ca2+-sparing effects. The HETE beneficial result in reducing Ca2+ excretion was confirmed through the protective effect found in front of the urinary calcium oxalate precipitation and crystallization. The combination with HCTZ, a classic diuretic and saluretic medicine, significantly enhanced HETE-induced diuresis, natriuresis, and the Ca2+-sparing effect. On the other hand, the K+-sparing action was improved in the combination of HETE with amiloride, a standard K+-sparing diuretic. In contrast, the combination of HETE with atropine (a non-selective muscarinic receptor antagonist) and indomethacin (an inhibitor of the cyclooxygenase enzyme), promoted an important reduction in urinary volume, but interestingly the natriuretic effect was maintained. CONCLUSION: This study contributed to the preclinical validation of the diuretic efficacy of T. erecta, highlighting this species as promising for the development of new pharmacological strategies for the management of kidney disorders.


Asunto(s)
Diuréticos/farmacología , Flores/química , Hipertensión/tratamiento farmacológico , Natriuresis/efectos de los fármacos , Extractos Vegetales/farmacología , Tagetes/química , Animales , Presión Sanguínea/efectos de los fármacos , Diuresis/efectos de los fármacos , Diuréticos/química , Femenino , Masculino , Fitoterapia , Extractos Vegetales/química , Plantas Medicinales , Ratas , Ratas Endogámicas SHR , Ratas Wistar
2.
Drug Dev Res ; 80(6): 800-806, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31243798

RESUMEN

Gymnosperma glutinosum (Spreng) Less (Asteraceae) is a shrub used in traditional medicine for the treatment of inflammatory and renal diseases. The ent-dihydrotucumanoic acid (DTA) is a diterpene obtained from G. glutinosum. This study evaluated the antioxidant, genotoxic, and diuretic properties of DTA, as well as its in vitro and in vivo anti-inflammatory actions. The antioxidant actions of DTA were assessed with the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), ferric reducing antioxidant power (FRAP), and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) assays, the genotoxic action was assessed with the comet assay, and the diuretic effects of DTA were assessed using metabolic cages. The anti-inflammatory actions were evaluated using primary murine peritoneal macrophages stimulated with LPS and the λ-carrageenan-induced hind paw edema test. DTA lacked antioxidant (IC50 > 25,000 µg/mL) activity in the ABTS, FRAP, and DPPH assays. DTA at 500-1,000 µg/mL showed moderate genotoxicity. In LPS-stimulated macrophages, DTA showed IC50 values of 74.85 µg/mL (TNF-α) and 58.12 µg/mL (NO), whereas the maximum inhibition of IL-6 (24%) and IL-1ß (36%) was recorded at 200 µg/mL. DTA induced in vivo anti-inflammatory effects with ED50 = 124.3 mg/kg. The in vitro anti-inflammatory activity of DTA seems to be associated with the decrease in the release of TNF-α and NO. DTA promoted the excretion of urine (ED50 = 86.9 mg/kg), Na+ (ED50 = 66.7 mg/kg), and K+ (ED50 = 8.6 mg/kg). The coadministration of DTA with L-NAME decreased the urinary excretion shown by DTA alone. Therefore, the diuretic activity is probably associated with the participation of nitric oxide synthase. In conclusion, DTA exerted anti-inflammatory and diuretic effects, but lacked antioxidant effects.


Asunto(s)
Antiinflamatorios/farmacología , Antioxidantes/farmacología , Diterpenos/farmacología , Diuréticos/farmacología , Animales , Antiinflamatorios/química , Antiinflamatorios/uso terapéutico , Antiinflamatorios/toxicidad , Antioxidantes/química , Antioxidantes/uso terapéutico , Antioxidantes/toxicidad , Asteraceae , Benzotiazoles/química , Compuestos de Bifenilo/química , Carragenina , Ensayo Cometa , Citocinas/metabolismo , Diterpenos/química , Diterpenos/uso terapéutico , Diterpenos/toxicidad , Diuréticos/química , Diuréticos/uso terapéutico , Diuréticos/toxicidad , Edema/inducido químicamente , Edema/tratamiento farmacológico , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Lipopolisacáridos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Ratones Endogámicos BALB C , Óxido Nítrico/metabolismo , Picratos/química , Ácidos Sulfónicos/química
3.
J Med Food ; 22(4): 393-407, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30990753

RESUMEN

Although leaves of Anchietea salutaris are used in Brazilian traditional medicine, there is no available data in the literature proving its efficacy and safety. Thus, the aim of the study was to perform a meticulous botanical, phytochemical, toxicological, and pharmacological investigation of A. salutaris in Wistar rats. At first, a morphoanatomical characterization of Anchietea pyrifolia leaves and stems was performed. Then, a purified infusion (ethanol-soluble fraction obtained from A. pyrifolia [ESAP]) was obtained followed by its chemical profile elucidation. Furthermore, an acute toxicity test was performed, and the acute and prolonged diuretic and hypotensive effects were also evaluated in Wistar rats. Finally, the vasodilatory responses of ESAP in mesenteric vascular beds were investigated. The main secondary metabolites identified from ESAP were O-glycosylated flavonoids, chlorogenic acids, and phenylpropanoic acid derivatives. ESAP did not promote any toxic effects in female rats nor increased urinary excretion in male rats after a single exposure. However, ESAP significantly reduced renal elimination of sodium, potassium, and chloride after prolonged treatment. An ESAP highest dose promoted significant acute hypotension without affecting blood pressure levels after prolonged use. Furthermore, its cardiovascular effects seem to be related with the calcium-activated potassium channel activation in resistance vessels.


Asunto(s)
Antihipertensivos/administración & dosificación , Hipertensión/tratamiento farmacológico , Extractos Vegetales/administración & dosificación , Violaceae/química , Animales , Antihipertensivos/efectos adversos , Antihipertensivos/química , Presión Sanguínea/efectos de los fármacos , Brasil , Diuréticos/administración & dosificación , Diuréticos/efectos adversos , Diuréticos/química , Femenino , Humanos , Hipertensión/genética , Hipertensión/metabolismo , Hipertensión/fisiopatología , Masculino , Extractos Vegetales/efectos adversos , Extractos Vegetales/química , Hojas de la Planta/química , Canales de Potasio Calcio-Activados/genética , Canales de Potasio Calcio-Activados/metabolismo , Ratas Wistar
4.
J Enzyme Inhib Med Chem ; 31(6): 1102-10, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26497704

RESUMEN

Three salts of 5-amino-2-sulfonamide-1,3,4-thiadiazole (Hats) were prepared and characterized by physico-chemical methods. The p-toluensulfonate, the methylsulfonate, and the chlorhydrate monohydrate salts of Hats were evaluated as carbonic anhydrase (CA, EC 4.2.1.1) inhibitors (CAIs) and as anticonvulsants and diuretics, since many CAIs are clinically used as pharmacological agents. The three Hats salts exhibited diuretic and anticonvulsant activities with little neurotoxicity. The human (h) isoforms hCA I, II, IV, VII, IX, and XII were inhibited in their micromolar range by these salts, whereas pathogenic beta and gamma CAs showed similar, weak inhibitory profiles.


Asunto(s)
Acetazolamida/análogos & derivados , Anticonvulsivantes/farmacología , Inhibidores de Anhidrasa Carbónica/farmacología , Diuréticos/farmacología , Sulfonamidas/química , Tiadiazoles/farmacología , Anticonvulsivantes/química , Inhibidores de Anhidrasa Carbónica/química , Diuréticos/química , Humanos , Isoenzimas/antagonistas & inhibidores , Tiadiazoles/química
5.
Plant Foods Hum Nutr ; 69(3): 189-95, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24862084

RESUMEN

The exploration of nature as a source of sustainable, novel bioactive substances continues to grow as natural products play a significant role in the search for new therapeutic and agricultural agents. In this context, plants of the genus Pereskia (Cactaceae) have been studied for their biological activities, and are evolving as an interesting subject in the search for new, bioactive compounds. These species are commonly used as human foodstuffs and in traditional medicine to treat a variety of diseases. This review focuses on the bioactivity and chemical composition of the genus Pereskia, and aims to stimulate further studies on the chemistry and biological potential of the genus.


Asunto(s)
Cactaceae/química , Extractos Vegetales/farmacología , Analgésicos/química , Analgésicos/farmacología , Antiinfecciosos/química , Antiinfecciosos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Cactaceae/clasificación , Diuréticos/química , Diuréticos/farmacología , Humanos , Extractos Vegetales/química , Hojas de la Planta/química , Especias/análisis
6.
J Pharm Biomed Anal ; 88: 152-6, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24055851

RESUMEN

The identification and quantification of crystalline phases of antihypertensive drugs - Losartan potassium (LOS-K), Hydrochlorothiazide (HCTZ) and Chlorthalidone (CTD) were carried out by means of X-ray powder diffraction data and the Rietveld method. Quantitative phase analyses of Losartan potassium/Chlorthalidone (LOS-K/CTD) and Losartan potassium/Hydrochlorothiazide (LOS-K/HCTZ) combinations were also evaluated. The results indicated that for diuretics (HCTZ and CTD) only one crystalline phase was found in samples, and for LOS-K the crystal structure showed similarity between the Bragg peaks to the phase described as monoclinic and space group P21/c. After one year storage, the orthorhombic one was also observed in this sample.


Asunto(s)
Antihipertensivos/análisis , Clortalidona/análisis , Hidroclorotiazida/análisis , Losartán/análisis , Bloqueadores del Receptor Tipo 1 de Angiotensina II/análisis , Química Farmacéutica , Cristalización , Diuréticos/química , Estabilidad de Medicamentos , Polvos , Temperatura , Factores de Tiempo , Difracción de Rayos X
7.
Braz. j. pharm. sci ; 47(3): 593-600, July-Sept. 2011. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-602676

RESUMEN

The objective of this study was to prepare and evaluate chronotherapeutic drug delivery systems (ChrDDs) of torsemide. Compression coated tablets (CCT) containing torsemide in the core tablet were prepared by the compression coating technique with different grades of polyethylene oxide (PEO WSR 301 & 1105). The optimized formulations were characterised for tabletting parameters and drug polymer interaction by Fourier-Transform Infrared Spectroscopy (FTIR).The hardness of all the CCT using PEO WSR 301 & PEO WSR 1105 were in the range 6-8 kg/cm² & 5.5 to 7 kg/cm² respectively. Their friability values were <0.3 percent. All the CCT showed a clear lag time but finalized as per the predetermined lag time. As the amount of PEO was increased in the outer layer the drug released was delayed. The drug content of all the CCT was >99 percent. The FTIR studies showed no interaction throughout the process of development. Formulations of F7 and of P7 were considered optimized formulations since they yielded a predetermined lag time of 6h before burst release. Hence, these formulations can be exploited to achieve chronotherapeutic drug delivery systems of Torsemide for the treatment of hypertension at the time the patient needs it.


O objetivo deste estudo foi preparar e avaliar sistemas cronoterapêuticos de liberação de fármacos (ChrDDs) de torsemida. Comprimidos revestidos por compressão (CCT) contendo torsemida no (núcleo) foram preparados pela técnica de revestimento por compressão, com diferentes categorias de óxido de polietileno (PEO WSR 301 & 1105). As formulações otimizadas foram caracterizadas por parâmetros de compressão e interação fármaco polímero por Infravermelho com Transformada de Fourier (FTIR). A dureza dos CCT utilizando PEO WSR 301 e PEO WSR 1105 foi entre 6-8 kg/cm² e 5,5 a 7 kg/cm², respectivamente. Os valores de friabilidade foram <0,3 por cento. Todos os CCT mostraram claro tempo de retardo, mas finalizaram de acordo com o tempo de retardo pré-determinado. À medida que a quantidade de PEO aumentava na camada mais externa, a liberação do fármaco era retardada. O teor de fármaco em todos os CCT foi >99 por cento. Os estudos de FTIR mostraram que não h[a interação durante o processo de desenvolvimento. As formulações F7 e P7 foram consideradas otimizadas, uma vez que resultaram em tempo de retardo pré-determinado de 6 h antes da liberação por meio de explosão. Dessa forma, estas formulações podem ser exploradas para se obter sistemas de liberação.


Asunto(s)
Diuréticos/agonistas , Diuréticos/farmacocinética , Diuréticos/química , Desarrollo Experimental , Técnicas In Vitro , Cronoterapia de Medicamentos , Preparaciones de Acción Retardada/química
8.
Molecules ; 16(6): 4482-99, 2011 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-21623317

RESUMEN

Hydrochlorothiazide is a common diuretic antihypertensive drug of the thiazide family. Its poor aqueous solubility is one of the reasons for its limited bioavailability after oral administration. This work aimed at the development of a hydrochlorothiazide:ß-cyclodextrin (HTZ:ß-CD) pharmaceutical composition in order to improve water solubility and bioavailability of the drug. The HTZ:ß-CD complexes were prepared by three different methods: spray-drying, freeze-drying and fluid bed. Complexes were characterized by thermal analysis, Fourier transform-infrared (FTIR) spectroscopy, powder X-ray diffractometry, NMR (2D-ROESY), scanning electron microscopy (SEM), particle analysis and intrinsic dissolution. The findings reveal that three binary systems prepared presented better solubility results in comparison with free HTZ. Increased diuretic effect was observed to HTZ:ß-CD obtained by fluid bed in comparison to free drug in rats. Results taken together suggest that pharmacological effect of HTZ in complex was increased by solubility improvement promoted by cyclodextrin.


Asunto(s)
Diuréticos/química , Diuréticos/farmacología , Hidroclorotiazida/química , Hidroclorotiazida/farmacología , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacología , Animales , Química Farmacéutica , Capacidad de Concentración Renal/efectos de los fármacos , Masculino , Resonancia Magnética Nuclear Biomolecular , Polvos/química , Polvos/farmacología , Ratas , Ratas Wistar , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
9.
Rev. bras. plantas med ; Rev. bras. plantas med;13(4): 375-381, 2011. ilus, graf
Artículo en Portugués | LILACS | ID: lil-611441

RESUMEN

O milho (Zea mays L.) possui nos estigmas (cabelo de milho) substâncias que o tornam diurético, podendo ser importante no controle da hipertensão. No presente estudo, foi investigado o efeito do extrato aquoso (EA) do cabelo de milho sobre o fluxo renal de água (V) e eletrólitos e a pressão arterial (PA) em ratos Wistar anestesiados. Foram realizados 3 grupos: I) Controle - administração intragástrica (AI) de 1mL de água destilada; II) AI de 1 mL de EA de cabelo de milho a 20 por cento e III) AI de 1 mL de solução contendo furosemida. Canulou-se a artéria carótida esquerda para mensuração da PA, de 10 em 10 minutos, e a bexiga urinária, para mensuração de V de 30 em 30 minutos e da carga excretada dos íons sódio (Qe (Na+)) e potássio (Qe (K+)). Protocolo experimental: quatro períodos de 30 minutos cada: basal (avaliação dos parâmetros basais) e experimentais (Ex) 1, 2 e 3 (30, 60 e 90 minutos após a AI, respectivamente). O Grupo I não apresentou alterações significativas entre os períodos nos parâmetros analisados (p>0,05). O Grupo II apresentou aumento significativo (p<0,05) em V, em Qe (Na+) e em Qe (K+) nos períodos Ex2 e Ex3, com redução significativa na PA (p<0,05) em Ex2 e Ex3. Conforme esperado, o Grupo III apresentou aumento significativo em V nos períodos Ex2 (p<0,05) e Ex3 (p<0,001), aumento em Qe (Na+) em Ex1 (p<0,05), Ex2 (p<0,001) e Ex3 (p<0,001) e aumento em Qe (K+) em Ex2 (p<0,05) e Ex3 (p<0,001), com redução significativa na PA (p<0,05) em Ex2 e Ex3. Os dados mostram que o EA do cabelo de milho possui efeito diurético, porém não age como um diurético "de alça", uma vez que não levou à expoliação de potássio e nem a uma excreção tão acentuada de sódio quanto à furosemida.


The corn (Z. mays) has in its stigmas (corn silks) substances that make it diuretic, which may be important in hypertension control. In this study, the effect of aqueous extract (AE) of corn silks on the renal flow of water (V) and electrolytes and arterial pressure (AP) was investigated in anesthetized Wistar rats. Three groups were tested: I) Control - intragastric administration (IA) of 1mL of distilled water, II) IA of 1 mL of AE of corn silks at 20 percent and III) IA of 1 mL of a solution containing furosemide. Cannulation was performed in the left carotid artery to measure AP, at every 10 minutes, and in the urinary bladder to measure V, at every 30 minutes, and the excreted load of ions sodium (Qe (Na+)) and potassium (Qe (K+)). Experimental protocol: four periods of 30 minutes each: basal (evaluation of basal parameters) and experimental (Ex) 1, 2 and 3 (30, 60 and 90 minutes after IA, respectively). Group I had no significant differences between periods for the analyzed parameters (p>0.05). Group II presented a significant increase (p<0.05) in V, Qe (Na+) and Qe (K+) in periods Ex2 and Ex3, with significant reduction in AP (p<0.05) in Ex2 and Ex3. As expected, Group III had a significant increase in V in periods Ex2 (p<0.05) and Ex3 (p<0.001), an increase in Qe (Na+) in Ex1 (p<0.05), Ex2 (p<0.001) and Ex3 (p<0.001) and an increase in Qe (K+) in Ex2 (p<0.05) and Ex3 (p<0.001), with an important reduction in AP (p<0.05) in Ex2 and Ex3. These data show that AE of corn silks has a diuretic effect but does not act as a loop diuretic since it did not lead to potassium loss or marked sodium loss, compared to furosemide.


Asunto(s)
Animales , Masculino , Ratas , Agua Corporal/química , Electrólitos/química , Extractos Vegetales/uso terapéutico , Presión Arterial , Ratas Wistar , Orina , Zea mays/efectos adversos , Zea mays , Diuréticos/efectos adversos , Diuréticos/química , Diuréticos/uso terapéutico , Plantas Medicinales/efectos adversos , Plantas Medicinales/toxicidad
10.
Anal Sci ; 25(7): 897-901, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19609030

RESUMEN

This paper describes a green analytical procedure for the determination of bumetanide using diffuse reflectance spectroscopy. The proposed method is based on reflectance measurements of a violet compound produced from a spot test reaction between bumetanide and p-dimethylaminocinnamaldehyde (p-DAC) in an acid medium, using filter paper as a solid support. The best conditions for the reaction have been found by experimental design methodologies. All reflectance measurements were carried out at 525 nm, and the linear range was from 1.37 x 10(-4) to 1.37 x 10(-3) mol L(-1), with a correlation coefficient of 0.998. The detection limit was estimated to be 3.98 x 10(-5) mol L(-1). Five commercial medicines containing bumetanide were analyzed by the proposed method. No interferences were observed from the common excipients present in pharmaceutical formulations. The results were favorably compared with those obtained by the United States Pharmacopoeia procedure at 95% confidence level.


Asunto(s)
Bumetanida/análisis , Diuréticos/análisis , Tecnología Química Verde/métodos , Preparaciones Farmacéuticas/química , Análisis Espectral/métodos , Bumetanida/química , Cinamatos/química , Color , Diuréticos/química , Filtración , Concentración de Iones de Hidrógeno , Luz , Factores de Tiempo
11.
Int J Pharm ; 378(1-2): 187-93, 2009 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-19477254

RESUMEN

A simple chemometric approach to differentiate among the three crystalline polymorphs of the model drug Furosemide (FUR) in a pharmaceutical dosage form is presented. The proposed method is based on the principal component analysis with confidence regions (PCA-CR) comparison of the dissolution profiles of the test pharmaceutical formulation, and formulations containing the different polymorphs, employed as the corresponding references. For the elaboration of the references, FUR polymorphs I, II and III were prepared, characterized and compounded with the excipients found in the test commercial formulation. The dissolutions were carried out in a discriminating HCl-KCl dissolution medium (pH 2.2), and the corresponding profiles were constructed from the absorbances (274 nm) of the dissolution samples. PCA-CR was able to differentiate among the three crystalline polymorphs of FUR and to confirm the presence of polymorph I in the test sample, with 99% statistical confidence. The PCA-CR results were compared with those obtained by a bootstrap-mediated implementation of Moore and Flanner's difference factor (f(2)). The same conclusion was reached employing an f(2)-based comparison, despite its inability to differentiate between polymorphs II and III. Therefore, PCA-CR may be considered a complementary and useful tool for probing the polymorphic form present in a pharmaceutical formulation.


Asunto(s)
Diuréticos/química , Furosemida/química , Análisis de Componente Principal/métodos , Química Farmacéutica/métodos , Cristalización , Concentración de Iones de Hidrógeno , Solubilidad , Tecnología Farmacéutica/métodos
12.
Z Naturforsch C J Biosci ; 55(5-6): 478-80, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10928563

RESUMEN

We have isolated two phytoconstituents present in the B. forficata leaves, a medicinal plant employed in folk medicine specially for the treatment of diabetes. These compounds were isolated by column chromatography and identified as beta-sitosterol and kaempferol-3,7-dirhamnoside (kaempferitrin) by spectroscopical data and comparison with authentic samples. A comparative study with different parts of the plant indicated that the latter is present only in the leaves, suggesting that it might be useful for a suitable quality control of phytotherapeutics which contain this organ of B. forficata in its composition.


Asunto(s)
Fabaceae/química , Flavonoides/análisis , Quempferoles , Plantas Medicinales/química , Sitoesteroles/análisis , Brasil , Diuréticos/análisis , Diuréticos/química , Flavonoides/química , Hipolipemiantes/análisis , Hipolipemiantes/química , Extractos Vegetales/química , Hojas de la Planta/química , Sitoesteroles/química
13.
Int J Pharm ; 195(1-2): 45-53, 2000 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-10675682

RESUMEN

Solid dispersions and physical mixtures were prepared and characterized by X-ray diffraction, infrared spectroscopy, electronic microscopy and dissolution rate studies. The characterization with X-ray diffraction showed a transition from the crystalline to the amorphous phase. A new phase near 50% Furosemide concentration with both types of carriers was present. From infrared spectroscopy strong interactions between amine and carbonyl groups from both the Furosemide and the polymers were found. Electronic microscopy analysis showed that the Furosemide changed its crystalline habit from needle to a new spherical phase, with diameter near to 1 microm. Solid dispersions were prepared in order to modify the system characteristics. The Furosemide dissolution rate was determined in order to follow the behavioural changes of the system. Scanning electron microscopy showed the presence of micro spheres within the polymeric matrix, and the channels formed due to the Furosemide dissolution inside the Eudragit: this fact modified the release pattern of the Furosemide system.


Asunto(s)
Resinas Acrílicas/química , Preparaciones de Acción Retardada/química , Diuréticos/química , Furosemida/química , Química Farmacéutica , Cristalografía por Rayos X , Portadores de Fármacos , Geles/química , Microscopía Electrónica , Ácidos Polimetacrílicos , Espectrofotometría Infrarroja
14.
Pharmazie ; 54(12): 920-2, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10631756

RESUMEN

The photodegradation process of the phototoxic diuretic drug chlorthalidone was studied. The products of its photolysis under UV-B were isolated and identified. Chlorthalidone was found to be active when examined by photohemolysis on human erythrocytes, but not in the presence of the isolated photoproducts. Inhibition of the photohemolysis process induced by chlorthalidone on addition of reduced glutathione (GSH) or ascorbic acid suggests the involvement of radicals species. The inhibition with 1,4-diazabycyclo [2.2.2] octane (DABCO), sodium azide (NaN3) sowie 2,5-dimethylfuran proof the participation of singlet oxygen (1O2) in this process.


Asunto(s)
Clortalidona/química , Clortalidona/toxicidad , Dermatitis Fototóxica/patología , Diuréticos/química , Diuréticos/toxicidad , Clortalidona/efectos de la radiación , Cromatografía Líquida de Alta Presión , Diuréticos/efectos de la radiación , Transporte de Electrón , Eritrocitos/efectos de los fármacos , Radicales Libres , Humanos , Técnicas In Vitro , Espectroscopía de Resonancia Magnética , Fotoquímica , Fotólisis , Rayos Ultravioleta
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