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1.
Pol J Radiol ; 85: e125-e131, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32322318

RESUMEN

PURPOSE: Pulmonary tuberculosis (PTB) is one of the major health problems in the elderly population, causing significant morbidity and mortality. The aim of this study is to evaluate the significance of the high-resolution computed tomography (HRCT) modality for the diagnosis of PTB, in comparison to culture test. MATERIAL AND METHODS: Thoracic HRCT images of the study population, comprising 124 patients clinically suspected for PTB with smear and culture reports, were analysed for sensitivity and specificity of the HRCT test. Features of active PTB were centrilobular nodules, 'tree-in-bud' pattern densities, macro-nodules, consolidations, cavitary lesions, ground-glass opacities, and miliary nodules. RESULTS: Among the study population, 108 cases presented HRCT features of active PTB and the remaining cases were negative but had presented a few features mimicking PTB. As inferred from positive culture test results, 106 cases had active PTB, the remaining cases were culture negative for PTB. False-positive (FP) or 'type I error' cases, and false-negative (FN) or 'type II error' cases were ascertained by Bayes' theorem. Sensitivity (true positive rate) and specificity (true negative rate) of HRCT test were 0.8125 and 0.8571, respectively. CONCLUSIONS: For proper diagnosis the predictive capability, as two values of 'a posteriori probability', was computed; the mean value of 'a posteriori probability' for HRCT was 0.6358. When its culture test was positive, the HRCT test was 69.56-92.85% efficient in ascertaining positive results with a sample; on the other hand, when its culture test was negative it was 66.66-100% efficient for a negative result. Thus, the HRCT test is considerably dependable.

2.
J Med Microbiol ; 56(Pt 9): 1196-1204, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17761483

RESUMEN

Leishmaniasis remains a major health problem of the tropical and subtropical world. The visceral form causes the most fatalities if left untreated. Dramatic increases in the rates of infection and drug resistance and the non-availability of safe vaccines have highlighted the need for identification of novel and inexpensive anti-leishmanial agents. This study reports that racemoside A, a water-soluble steroidal saponin purified from the fruits of Asparagus racemosus, is a potent anti-leishmanial molecule effective against antimonial-sensitive (strain AG83) and -unresponsive (strain GE1F8R) Leishmania donovani promastigotes, with IC(50) values of 1.15 and 1.31 microg ml(-1), respectively. Incubation of promastigotes with racemoside A caused morphological alterations including cell shrinkage, an aflagellated ovoid shape and chromatin condensation. This compound exerts its leishmanicidal effect through the induction of programmed cell death mediated by the loss of plasma membrane integrity as detected by binding of annexin V and propidium iodide, loss of mitochondrial membrane potential culminating in cell-cycle arrest at the sub-G(0)/G(1) phase, and DNA nicking shown by deoxynucleotidyltransferase-mediated dUTP end labelling (TUNEL). Racemoside A also showed significant activity against intracellular amastigotes of AG83 and GE1F8R at a 7-8-fold lower dose, with IC(50) values of 0.17 and 0.16 microg ml(-1), respectively, and was non-toxic to murine peritoneal macrophages up to a concentration of 10 microg ml(-1). Hence, racemoside A is a potent anti-leishmanial agent that merits further pharmacological investigation.


Asunto(s)
Antiprotozoarios/farmacología , Apoptosis , Leishmania donovani/efectos de los fármacos , Saponinas/farmacología , Esteroides/farmacología , Animales , Anexina A5/metabolismo , Antiprotozoarios/toxicidad , Asparagus/química , Permeabilidad de la Membrana Celular/efectos de los fármacos , Supervivencia Celular , Células Cultivadas , Roturas del ADN de Cadena Simple , Etiquetado Corte-Fin in Situ , Concentración 50 Inhibidora , Leishmania donovani/citología , Macrófagos Peritoneales/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Extractos Vegetales/farmacología , Propidio/metabolismo , Saponinas/aislamiento & purificación , Esteroides/aislamiento & purificación
3.
J Ethnopharmacol ; 110(2): 189-99, 2007 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-17276634

RESUMEN

Woodfordia fruticosa Kurz of the family Lythraceae is a plant of tropical and subtropical region with a long history of medicinal use. A wide range of chemical compounds including tannins (especially those of macrocyclic hydrolysable class), flavonoids, anthraquinone glycosides, and polyphenols have been isolated from this species in recent times. Extracts and metabolites of this plant, particularly those from flowers and leaves, possess useful pharmacological activities. A comprehensive account of the chemical constituents and the biological activities is presented and a critical appraisal of the ethnopharmacological issues is included in view of the many recent findings of importance on this plant.


Asunto(s)
Fitoterapia , Extractos Vegetales/química , Extractos Vegetales/farmacología , Woodfordia/química , Antraquinonas , Etnofarmacología , Flavonoides , Glicósidos , Humanos , Medicina Tradicional , Fenoles , Extractos Vegetales/uso terapéutico , Plantas Medicinales/química , Polifenoles , Taninos
4.
Phytochemistry ; 67(2): 183-90, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16343564

RESUMEN

Bioguided-fractionation of the methanol extract of the leaves of Careya arborea led to isolation of a triterpenoid saponin, designated arborenin, and characterized as 3-O-beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl-2 alpha,3beta-dihydroxy-taraxast-20-en-28-oic acid (1), together with desacylescin III (2). The structures were determined on the basis of extensive 2D NMR spectroscopic analysis. The saponin showed in vitro antileishmanial activity against Leishmania donovani (strain AG 83).


Asunto(s)
Antiprotozoarios/farmacología , Lecythidaceae/química , Leishmania donovani/efectos de los fármacos , Hojas de la Planta/química , Saponinas/farmacología , Triterpenos/farmacología , Animales , Antiprotozoarios/química , Antiprotozoarios/aislamiento & purificación , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética/normas , Conformación Molecular , Datos de Secuencia Molecular , Pruebas de Sensibilidad Parasitaria , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Estándares de Referencia , Saponinas/química , Saponinas/aislamiento & purificación , Triterpenos/química , Triterpenos/aislamiento & purificación
5.
Phytochemistry ; 67(13): 1316-21, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16759676

RESUMEN

Three steroidal saponins, racemosides A (1), B (2) and C (3), were isolated from the methanolic extract of the fruits of Asparagus racemosus, and characterized as (25S)-5beta-spirostan-3beta-ol-3-O-{beta-D- glucopyranosyl (1-->6)-[alpha-L-rhamnopyranosyl (1-->6)-beta-D-glucopyranosyl (1-->4)]-beta-D-glucopyranoside}, (25S)-5beta-spirostan-3beta-ol-3-O-alpha-L-rhamnopyranosyl (1-->6)-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranoside and (25S)-5beta-spirostan-3beta-ol-3-O-{alpha-L-rhamnopyranosyl-(1-->6)-[alpha-L-rhamnopyranosyl (1-->4)]-beta-D-glucopyranoside}, respectively, by spectrometric analysis and some chemical strategies.


Asunto(s)
Asparagus/química , Frutas/química , Saponinas/química , Esteroides/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Saponinas/aislamiento & purificación , Esteroides/aislamiento & purificación
6.
J Drug Target ; 14(4): 171-9, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16777677

RESUMEN

Bassic acid, an unsaturated triterpene acid isolated from Mimusops elangii, was tested for its antileishmanial properties both in vitro and in vivo. The in vitro antileishmanial activity of bassic acid being encouraging, its activity in vivo was evaluated in hamster models of visceral leishmaniasis, both in free form, as well as incorporated in two different delivery systems, viz microemulsions and polylactide nanoparticles. The delivery systems were prepared by published protocols. The percentage intercalation of bassic acid in nanoparticles and microemulsion was found to be about 50 and 100, respectively, when determined at its absorption maxima (lambda(max)) 285 nm (epsilon(m) = 2.3 x 10(2) M(-1) cm(-1)). At an equivalent dose of 2 mg kg(-1) body weight, when injected subcutaneously for a total of six doses in 15 days, bassic acid was found to reduce spleen parasite loads by 45, 62 and 78% in free, microemulsion-incorporated and nanoparticle-incorporated forms, respectively. A comparison of specific biochemical tests related to normal liver and kidney functions revealed that the nanoparticulate form was successful in significantly reducing the hepatotoxicity and nephrotoxicity of the free drug, but the microemulsion delivery system was less effective and toxic to liver and kidney to some extent. Confocal microscopic images of Leishmania donovani promastigotes treated with bassic acid revealed that the drug induced necrotic cell death due to non-specific membrane damage. Because of its high efficacy as well as non-hepatotoxicity and non-nephrotoxicity, the nanoparticulate form of bassic acid may be considered for clinical application in humans rather than the microemulsion incorporated form.


Asunto(s)
Antiprotozoarios/uso terapéutico , Portadores de Fármacos/uso terapéutico , Leishmania donovani/efectos de los fármacos , Leishmaniasis Visceral/tratamiento farmacológico , Triterpenos/uso terapéutico , Animales , Antiprotozoarios/farmacología , Cricetinae , Portadores de Fármacos/farmacología , Emulsiones/farmacología , Emulsiones/uso terapéutico , Leishmania donovani/crecimiento & desarrollo , Leishmania donovani/ultraestructura , Leishmaniasis Visceral/parasitología , Microscopía Confocal , Nanoestructuras/química , Aceites , Pruebas de Sensibilidad Parasitaria , Poliésteres/uso terapéutico , Resultado del Tratamiento , Triterpenos/farmacología , Agua
7.
Artículo en Inglés | MEDLINE | ID: mdl-27939854

RESUMEN

INTRODUCTION: To evaluate diagnostic accuracy of high-resolution ultrasonography in differentiation of benign and malignant thyroid nodules in comparison to results of guided fine needle aspiration cytology based on the Bayes rule. OBJECTIVE: To assess the validity of ultrasonography results of thyroid nodules in comparison to guided fine needle aspiration cytology findings. METHODS: This study was done on randomly chosen 80 patients presented with palpable thyroid nodules, undergone real-time sonographic evaluation of thyroid nodules to characterize features, internal consistency, margins, echotexture, calcification, peripheral lucent halo and vascularity. Ultrasonography guided fine needle aspiration cytology studies of thyroid nodules were done. RESULTS: Palpable thyroid nodules were highly prevalent in fourth and fifth decades of life with female-male ratio, 4:1. Solid internal consistency was demonstrated by 75% malignant nodules. Hypoechogenicity and intra-nodular micro-calcifications were observed in 92% malignant nodules; 83% malignant nodules had intra-nodular vascularity and absence of peripheral halo. The pre-test prevalence of malignant nodules in the targeted population was 17.5%. As type I error, 2.5% false-positive cases and as type II error, 5.0% false-negative cases were detected. Values of sensitivity and specificity of the ultrasonography test were 71.43 and 96.97%, respectively. CONCLUSION: Malignant thyroid nodules demonstrated ultrasonography characteristics of hypoechoic texture, intra-nodular micro-calcifications, solid consistency, internal vascularity and absence of peripheral halo. The ultrasonography test has 92.5% diagnostic accuracy to differentiate malignant from benign lesions in comparison to the gold standard fine needle aspiration cytology test.

8.
Phytochemistry ; 61(4): 383-8, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12377230

RESUMEN

Three novel polyoxypregnane glycosides, volubiloside A, B and C (1-3), were isolated from the flowers of Dregea volubilis Linn., and their structures were elucidated as drevogenin D-3-O-beta-D-glucopyranosyl (1-->4)-6-deoxy-3-O-methyl-beta-D-allopyranosyl (1-->4)-beta-D-cymaropyranosyl (1-->4)-beta-D-cymaropyranoside, drevogenin D-3-O-beta-D-glucopyranosyl (1-->4)-6-deoxy-3-O-methyl-beta-D-allopyranosyl (1-->4)-beta-D-cymaropyranosyl (1-->4)-beta-D-digitoxopyranoside and drevogenin P-3-O-beta-D-glucopyranosyl (1-->4)-6-deoxy-3-O-methyl-beta-D-allopyranosyl (1-->4)-beta-D-cymaropyranosyl (1-->4)-beta-D-cymaropyranoside, respectively, on the basis of extensive NMR experiments, MALDI-TOF MS, and some chemical strategies.


Asunto(s)
Apocynaceae/química , Flores/química , Glicósidos/química , Glicósidos/aislamiento & purificación , Saponinas/química , Saponinas/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Estructura Molecular
9.
Braz. j. otorhinolaryngol. (Impr.) ; 84(1): 20-27, Jan.-Feb. 2018. tab
Artículo en Inglés | LILACS | ID: biblio-889353

RESUMEN

Abstract Introduction To evaluate diagnostic accuracy of high-resolution ultrasonography in differentiation of benign and malignant thyroid nodules in comparison to results of guided fine needle aspiration cytology based on the Bayes rule. Objective To assess the validity of ultrasonography results of thyroid nodules in comparison to guided fine needle aspiration cytology findings. Methods This study was done on randomly chosen 80 patients presented with palpable thyroid nodules, undergone real-time sonographic evaluation of thyroid nodules to characterize features, internal consistency, margins, echotexture, calcification, peripheral lucent halo and vascularity. Ultrasonography guided fine needle aspiration cytology studies of thyroid nodules were done. Results Palpable thyroid nodules were highly prevalent in fourth and fifth decades of life with female-male ratio, 4:1. Solid internal consistency was demonstrated by 75% malignant nodules. Hypoechogenicity and intra-nodular micro-calcifications were observed in 92% malignant nodules; 83% malignant nodules had intra-nodular vascularity and absence of peripheral halo. The pre-test prevalence of malignant nodules in the targeted population was 17.5%. As type I error, 2.5% false-positive cases and as type II error, 5.0% false-negative cases were detected. Values of sensitivity and specificity of the ultrasonography test were 71.43 and 96.97%, respectively. Conclusion Malignant thyroid nodules demonstrated ultrasonography characteristics of hypoechoic texture, intra-nodular micro-calcifications, solid consistency, internal vascularity and absence of peripheral halo. The ultrasonography test has 92.5% diagnostic accuracy to differentiate malignant from benign lesions in comparison to the gold standard fine needle aspiration cytology test.


Resumo Introdução Avaliar a precisão diagnóstica da ultrassonografia de alta resolução na diferenciação de nódulos tireoidianos benignos e malignos em comparação com os resultados da citologia de aspiração por agulha fina baseada na regra de Bayes. Objetivo Avaliar a validade dos resultados da USG de nódulos da tireoide em comparação com os resultados obtidos por citologia de aspiração por agulha fina. Método Este estudo foi feito em 80 pacientes selecionados aleatoriamente, que apresentavam nódulos palpáveis da tireoide, submetidos à avaliação ultrassonográfica em tempo real de nódulos da tireoide para estabelecer características, consistência interna, margens, ecotextura, calcificação, halo lucente periférico e vascularização. Foram feitos estudos por citologia de aspiração por agulha fina guiados pela USG dos nódulos de tireoide. Resultados Nódulos palpáveis da tireoide foram altamente prevalentes na quarta e quinta décadas de vida com uma razão sexo feminino-masculino de 4:1. A consistência interna sólida foi demonstrada em 75% de nódulos malignos. Hipoecogenicidade e microcalcificações intranodulares foram observadas em 92% de nódulos malignos; 83% dos nódulos malignos apresentaram vascularidade intranodular e ausência de halo periférico. A prevalência pré-teste de nódulos malignos na população alvo foi de 17,5%. Como erro tipo I, houve 2,5% de casos falso-positivos e como erro tipo II, foram detectados 5,0% de casos falso-negativos. Os valores de sensibilidade e especificidade do exame por USG foram de 71,43 e 96,97%, respectivamente. Conclusão Nódulos malignos da tireoide mostraram características de textura hipoecoica, microcalcificações intranodulares, consistência sólida, vascularidade interna e ausência de halo periférico na USG. O exame por USG tem 92,5% de precisão diagnóstica para diferenciar lesões malignas de benignas em comparação com o padrão ouro da citologia de aspiração por agulha fina.

10.
Antimicrob Agents Chemother ; 46(1): 259-61, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11751149

RESUMEN

2-(2"-Dichloroacetamidobenzyl)-3-(3'-indolylquinoline), designated indolylquinoline derivative A, reduced the splenic and the liver parasite burdens by >93.0% in Leishmania donovani-infected hamsters, whereas sodium antimony gluconate (SAG) reduced the burdens approximately 80.0%. Complete clearance of parasitemia from the livers and spleens was noticed when infected animals received indolylquinoline derivative A plus SAG, suggesting that indolylquinoline derivative A has potential as a new agent for sole or conjunctive therapy for leishmaniasis.


Asunto(s)
Gluconato de Sodio Antimonio/uso terapéutico , Antiprotozoarios/uso terapéutico , Indoles/uso terapéutico , Leishmaniasis Visceral/tratamiento farmacológico , Quinolinas/uso terapéutico , Animales , Cricetinae , Modelos Animales de Enfermedad , Quimioterapia Combinada , Resultado del Tratamiento
11.
Bioorg Med Chem ; 10(6): 1687-93, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11937327

RESUMEN

Some novel quinoline derivatives were prepared and tested for antileishmanial activity. 2-(2-Methylquinolin-4-ylamino)-N-phenylacetamide (2) was found to be significantly more active than the standard antileishmanial drug sodium antimony gluconate (SAG) in reducing the parasite load both in the spleen and liver at a much lower concentration in hamster models. The results suggest that the compound could be exploited as an antileishmanial drug.


Asunto(s)
Acetamidas/síntesis química , Acetamidas/farmacología , Acetanilidas , Aminoquinolinas/síntesis química , Aminoquinolinas/farmacología , Acetamidas/uso terapéutico , Aminoquinolinas/uso terapéutico , Animales , Antiprotozoarios/síntesis química , Antiprotozoarios/química , Antiprotozoarios/farmacología , Ciclo Celular/efectos de los fármacos , Cricetinae , Leishmania donovani/citología , Leishmania donovani/efectos de los fármacos , Leishmania donovani/crecimiento & desarrollo , Leishmaniasis/sangre , Leishmaniasis/tratamiento farmacológico , Leishmaniasis/enzimología , Leishmaniasis/parasitología , Hígado/efectos de los fármacos , Hígado/parasitología , Mesocricetus , Estructura Molecular , Bazo/efectos de los fármacos , Bazo/parasitología , Factores de Tiempo
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