RESUMO
The aim of this study was the encapsulation of trans-dehydrocrotonin (t-DCTN) and its inclusion complexes with hydropropyl-beta-cyclodextrin (HP-beta-CD) in liposomes to improve t-DCTN antitumor activity. The in vitro kinetic profiles of t-DCTN-loaded liposomes (LD) and t-DCTN:HP-beta-CD-loaded liposomes (LC) were evaluated using the dialysis technique. The antitumor activity of LD and LC were investigated against Sarcoma 180 in Swiss mice. Histopathological and hematological analyses were carried out. The amounts of t-DCTN and t-DCTN:HP-beta-CD inclusion complex encapsulated in liposomes were equivalent to 1 mg of t-DCTN. The encapsulation efficiencies of LD and LC were 95.0 +/- 3.8% and 91.1 +/- 5.6%, respectively. In relation to kinetics, the drug release profiles of t-DCTN are in substantial agreement with the Fickian model. The treatment of animals with LD and LC produced tumor inhibitions of 79.4 +/- 9.6% and 63.5 +/- 5.5%, respectively. The liposomal encapsulation of t-DCTN by entrapment in the phospholipid bilayer increased at twice the antitumor activity. Moreover, the liposomal formulations reduced the hepatotoxicity effect of the drug and no significant hematological toxicity was observed in the treated animals. However, the counting of platelets was slightly decreased. Thus, the results show that the development of liposomal formulations containing t-DCTN or t-DCTN:HP-beta-CD is an important advance for enabling this drug to be use in therapy.
Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Diterpenos Clerodânicos/administração & dosagem , Diterpenos Clerodânicos/farmacologia , 2-Hidroxipropil-beta-Ciclodextrina , Animais , Antineoplásicos/química , Química Farmacêutica , Diterpenos Clerodânicos/química , Diterpenos Clerodânicos/uso terapêutico , Cinética , Lipossomos , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Tamanho da Partícula , Análise de Regressão , Sarcoma/sangue , Sarcoma/tratamento farmacológico , Sarcoma/patologia , Eletricidade Estática , beta-Ciclodextrinas/químicaRESUMO
A case of a 37-week pregnant woman who developed a hemorrhagic syndrome and acute renal failure after contact with Lonomia caterpillars is reported. The accident also initiated labour and the patient gave birth to an alive child. Some pathophysiological aspects of the genital bleeding and of the acute renal failure are discussed.
Assuntos
Injúria Renal Aguda/etiologia , Mordeduras e Picadas de Insetos/complicações , Mariposas , Complicações na Gravidez/etiologia , Hemorragia Uterina/etiologia , Adulto , Animais , Feminino , Humanos , Recém-Nascido , Trabalho de Parto Prematuro/etiologia , Gravidez , SíndromeRESUMO
Quasi-elastic light scattering of carnauba wax in the liquid phase is obtained in a heterodyne setup, and dynamic processes are analyzed through electrophoresis. Nonspherical polar clusters are found, containing a net electrical charge. An applied square-wave electric field induces drift and rotation of these clusters.These effects are dependent on strength and frequency of the applied electric field. At 373 K and in the low frequency limit the local electric field strength is approximately 70 times the strength of the applied one. This enhancement is believed to be caused by collective orientation of the clusters. The electrophoretic mobility is 1.1 X 10(-12) m2/V sec in the high frequency limit and 7.4 X 10(-11) m2/V sec in the low frequency limit. The electric dipole moment is 6.3 X 10(-16) N(-1/2) m(-1/2) where N is the cluster density/cubic meter and the net charge is about one or two elementary charges.