Estudo da interação da natamicina com membranas fosfolipídicas incorporadas de esteróis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Amperometric glucose biosensor based on layer-by-layer films of microperoxidase-11 and liposome-encapsulated glucose oxidase

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cyclodextrin Inclusion Complexes Loaded in Particles as Drug Carrier Systems

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Dioctadecyldimethylammonium:Monoolein Nanocarriers for Efficient in Vitro Gene Silencing

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação de sistemas lipidicos nanoestruturados utilizados como estratégia para melhorar as propriedades biofarmaceuticas do praziquantel no tratamento da esquistossomose

Pós-graduação em Nanotecnologia Farmacêutica - FCFAR

The effects of the C-terminal amidation of mastoparans on their biological actions and interactions with membrane-mimetic systems

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Uso subconjuntival de lipossomas com rapamicina e tacrolimus tópico no tratamento de ceratoconjuntivite seca em cães

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Interaction of biologically-relevant peptides with membrane model systems

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Sistemas bioinspirados aplicados no estudo de interação e sensoriamento de derivados xantênicos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Síntese e estudos de sistemas de bioencapsulação associados a peptídeos antimicrobianos miméticos da toxina natural CcdB

Pós-graduação em Biotecnologia - IQ

Evaluation of testicular tissue of adult rats treated with cisplatin incorporated into the liposome

Cisplatin (CPL) is one of the most widely used and effective chemotherapeutic agents for the treatment of several human malignancies. However, it causes serious side effects, especially on reproduction. In order to reduce the undesirable effects caused by many drugs, liposomes have been used as a good system for drug delivery. The aim of this study was to investigate, for the first time, the effects of CPL incorporated into the dipalmitoyl phosphatidylcholine liposome (DPPC) on the testicular tissue of adult Wistar rats. The animals (n = 20) were distributed into four experimental groups: (a) control (distillated water); (b) liposome (DPPC, 1 mL), (c) cisplatin incorporated into liposome (CPL/DPPC), and (d) CPL (8 mg/kg body weight). The animals received a single intraperitoneal injection and were killed 10 days after each treatment for histopathological analysis of testes. The results showed that the testicular histomorphometric parameters in rats of DPPC and CPL/DPPC groups were similar to those of the control group. Meanwhile, rats of the CPL-treated group showed a variety of morphological alterations, including atrophy of seminiferous tubules and presence of multinucleated cells in the germinal epithelium. The incorporation of CPL into the liposome had no influence on the testicular weight or any other stereological parameters, but it was beneficial in maintaining the body weight of the animals. In conclusion, the liposome suppressed the cytotoxic effects caused by cisplatin in the testes of rats, suggesting a possible use in chemotherapy against cancer to reduce the side effects seen on reproduction.

28-mer fragment derived from enterocin CRL35 displays an unexpected bactericidal effect on listeria cells

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The effects of acute and chronic administration of phosphatidylserine on cell proliferation and survival in the dentate gyms of adult and middle-aged rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Skeletal muscle degeneration and regeneration after injection of bothropstoxin-II, a phospholipase A2 isolated from the venom of the snake Bothrops jararacussu

A myotoxic phospholipase A2, named bothropstoxin II (BthTX-II), was isolated from the venom of the South American snake Bothrops jararacussu and the pathogenesis of myonecrosis induced by this toxin was studied in mice. BthTX-II induced a rapid increase in plasma creatine kinase levels. Histological and ultrastructural observations demonstrate that this toxin affects muscle fibers by first disrupting the integrity of plasma membrane, as delta lesions were the earliest morphological alteration and since the plasma membrane was interrupted or absent in many portions. In agreement with this hypothesis, BthTX-II released peroxidase entrapped in negatively charged multilamellar liposomes and behaved as an amphiphilic protein in charge shift electrophoresis, an indication that its mechanism of action might be based on the interaction and disorganization of plasma membrane phospholipids. Membrane damage was followed by a complex series of morphological alterations in intracellular structures, most of which are probably related to an increase in cytosolic calcium levels. Myofilaments became hypercontracted into dense clumps which alternated with cellular spaces devoid of myofibrillar material. Later on, myofilaments changed to a hyaline appearance with a more uniform distribution. Mitochondria were drastically affected, showing high amplitude swelling, vesiculation of cristae, formation of flocculent densities, and membrane disruption. By 24 hr, abundant polymorphonuclear leucocytes and macrophages were observed in the interstitial space as well as inside necrotic fibers. Muscle regeneration proceeded normally, as abundant myotubes and regenerating myofibers were observed 7 days after BthTX-II injection. By 28 days regenerating fibers had a diameter similar to that of adult muscle fibers, although they presented two distinctive features: central location of nuclei and some fiber splitting. This good regenerative response may be explained by the observation that BthTX-II does not affect blood vessels, nerves, or basal laminae. © 1991.

Photo-induced destruction of giant vesicles in methylene blue solutions

We study the photodecomposition of phospholipid bilayers in aqueous solutions of methylene blue. Observation of giant unilamellar vesicles under an optical microscope reveals a consistent pattern of membrane disruption as a function of methylene blue concentration and photon density for different substrates supporting the vesicles.