Ruy de Souza Lino Junior

Hancornia speciosa latex for biomedical applications: physical and chemical properties, biocompatibility assessment and angiogenic activity

The latex obtained from Hancornia speciosa is used in folk medicine for treatment of several diseases, such as acne, warts, diabetes, gastritis and inflammation. In this work, we describe the biocompatibility assessment and angiogenic properties of H. speciosa latex and its potential application in medicine. The physical–chemical characterization was carried out following different methodologies (CHN elemental analyses; thermogravimetric analyses and Fourier transform infrared spectroscopy). The biocompatibility was evaluated through cytotoxicity and genotoxicity tests in fibroblast mouse cells and the angiogenic properties were evaluated using the chick chorioallantoic membrane (CAM) assay model. The physical–chemical results showed that the structure of Hancornia speciosa latex biomembrane is very similar to that of Hevea brasiliensis (commercially available product). Moreover, the cytotoxicity and genotoxicity assays showed that H. speciosa latex is biocompatible with life systems and can be a good biomaterial for medical applications. The CAM test showed the efficient ability of H. speciosa latex in neovascularization of tissues. The histological analysis was in accordance with the results obtained in the CAM assay. Our data indicate that the latex obtained from H. speciosa and eluted in water showed significant angiogenic activity without any cytotoxic or genotoxic effects on life systems. The same did not occur with H. speciosa latex stabilized with ammonia. Addition of ammonia does not have significant effects on the structure of biomembranes, but showed a smaller cell survival and a significant genotoxicity effect. This study contributes to the understanding of the potentialities of H. speciosa latex as a source of new phytomedicines.

Low intensity ultrasound therapy induces angiogenesis and persistent inflammation in the chronic phase of the healing process of third degree burn wounds experimentally induced in diabetic and non-diabetic rats

PURPOSE To evaluate the effects of low intensity ultrasound on the healing process of third degree burn wounds in experimentally induced diabetic Wistar rats. METHODS One hundred rats were divided into: control group; non-diabetic treated group; diabetic control group; diabetic treated group. The therapy was performed with a 3MHz ultrasound application, pulsed emission at 100Hz frequency, modulated at 20% with a dosage of 0.5W/cm2 during three minutes throughout 30 days. The surgical debridement of the wound was performed once at day 2. The wounds were morphometrically, macroscopically and microscopically evaluated at 3, 7, 14, 21 and 30 days. RESULTS The wound contraction and collagen quantification were higher in all treated groups. Macroscopically, necrosis was higher in the diabetic control group. Granulation tissue was higher in treated groups during the proliferative and remodeling phase. Microscopically, there were greater mononuclear inflammatory infiltration, angiogenesis and fibroblast quantification in treated groups during the proliferative and remodeling phases. CONCLUSIONS therapeutic ultrasound is beneficial in the inflammatory and proliferative phases of the healing process because it controlled the necrotic tissue, increased the granulation tissue and wound contraction. However in the remodeling phase it is not beneficial because of the continued angiogenesis and a mononuclear inflammatory infiltration.

Anatomopathological study in BALB/c mice brains experimentally infected with Toxoplasma gondii

Toxoplasmosis is one of the most important diseases of the nervous central system, leading to severe symptoms and, many times, irreversible sequelae. This work demonstrated the main anatomopathological lesions caused by Toxoplasma gondii in brains from experimentally infected BALB/c mice. We analyzed 51 cases of mice that developed toxoplasmosis after experimental infection by intraperitoneal inoculation of blood, amniotic liquid and cerebrospinal fluid from fetuses, newly born children and pregnant women with clinical and laboratory signals of toxoplasmosis. In all experiments where we detected the parasite in mice we also detected pathological lesions in the animal brains with great polymorphism between experiments. Edema was the most found lesion in all cases. Besides, it was possible to demonstrate the inflammatory process in 82.4% of cases and necrosis in 64.7% of cases, in agreement with the literature that describes severe neurological damage in its hosts.

EXPERIMENTAL SUBCUTANEOUS CYSTICERCOSIS BY Taenia crassiceps IN BALB/c AND C57BL/6 MICE

SUMMARY Human cysticercosis is one of the most severe parasitic infections affecting tissues. Experimental models are needed to understand the host-parasite dynamics involved throughout the course of the infection. The subcutaneous experimental model is the closest to what is observed in human cysticercosis that does not affect the central nervous system. The aim of this study was to evaluate macroscopically and microscopically the experimental subcutaneous cysticercosis caused by Taenia crassiceps cysticerci in BALB/c and C57BL/6 mice. Animals were inoculated in the dorsal subcutaneous region and macroscopic and microscopic aspects of the inflammatory process in the host-parasite interface were evaluated until 90 days after the inoculation (DAI). All the infected animals presented vesicles containing cysticerci in the inoculation site, which was translucent at 7 DAI and then remained opaque throughout the experimental days. The microscopic analysis showed granulation tissue in BALB/c mice since the acute phase of infection evolving to chronicity without cure, presenting 80% of larval stage cysticerci at 90 DAI. While C57BL/6 mice presented 67% of final stage cysticerci at 90 DAI, the parasites were surrounded by neutrophils evolving to the infection control. It is possible to conclude that the genetic features of susceptibility (BALB/c) or resistance (C57BL/6) were confirmed in an experimental subcutaneous model of cysticercosis.

Facial trauma reconstruction with polymethyl methacrylate-A case report

Polymethyl methacrylate (PMMA) is a dermatologic filler commonly used in esthetic procedures. However, it can also be used in more severe cases such as reconstruction of facial traumas.

In vitro stressing factors altering the TCA cycle and morphology of Taenia crassiceps cysticerci

Abstract Objective To determine the morphological and biochemical alterations of in vitro induced Taenia crassiceps cysticerci by the presence of glucose, insulin and praziquantel isolated and in association. Methods The cysticerci were cultured for 24 h in supplemented Roswell Park Memorial Institute culture medium and added to two different concentrations of glucose, insulin and praziquantel. The morphometrical analysis was performed through the ImageJ programme, and the biochemical one through high-performance liquid chromatography. Results The exposure to the stressing factors led to alterations in the morphology and decrease in the growth rate of the parasite. Conclusions The metabolic effects are related to a decrease in the tricarboxylic acid cycle and fatty acids oxidation metabolites due to the drugs mode of action. Interestingly, the praziquantel, insulin and glucose association enhanced the drugs mode of action with a greater decrease of the tricarboxylic acid cycle metabolites.

TOXOPLASMOSE EXPERIMENTAL: AVALIAÇÃO DAS LESÕES HEPÁTICAS EM MURINOS

Toxoplasma gondii is the most common protozoan found in animals and humans and has been found in several of the host’s organs, including the liver. This study aimed to evaluate hepatic injury in experimental toxoplasmosis caused by two strains of T. gondii (RH and Me-49 strains). Biochemical and histopathological analyses were performed. It was possible to detect significant increases in serum levels of AST, ALT and LDH in both infections. The histopathological analysis showed inflammatory infiltration in the Me-49 strain infection and hyperemia and vasodilation in the RH strain infection. The acute infection (RH strain) induced hepatic failure and the death of the host. The chronic infection (ME-49 strain) caused liver damage but not enough to kill the host. Therefore this study validates the importance of biochemical concentrations for the evaluation of the infection, showing the importance of rigorous clinical assessment of T. gondii infected individuals.

AVALIAÇÃO DO EFEITO DE MEDICAMENTOS IMUNOSSUPRESSORES NA REATIVAÇÃO DA TOXOPLASMOSE CRÔNICA MURINA

This study evaluated the potential for reactivation of chronic toxoplasmosis in an immunocompromised murine model. To this end, BALB/c mice were orally infected with 20 cysts of Toxoplasma gondii ME-49 strain. After 60 days, the treatment with orally administered immunosuppressive drugs, such as azathioprine and dexamethasone, and cortisone acetate (administered by subcutaneous route) alone or in combination, started. The treatment was maintained for 28 days and afterwards the animals were euthanized and had their blood and organs removed for serological, histopathological and clinical examinations. When the drugs were associated to cortisone acetate, the clinical manifestations presented by the mice suggested reactivation due to epidermal lesions in 62.5% of the mice when compared to the control group. The results from this study suggest that with the murine model used, the chronic toxoplasmosis reactivation is greatly influenced by the immunosuppressive treatment proposed. In these cases, the clinic manifestations indicative of chronic toxoplasmosis reactivation may be present even before its detection by serological and histopathological methods.