Abstract in English:Lonomia obliqua caterpillar is frequently seen in accidents with humans especially in the south of Brazil. Patients develop a hemorrhagic syndrome that can be treated with specific antilonomic serum. A consumptive coagulopathy was found to be the main cause of bleeding complications observed in patients after contact with L. obliqua. Studies revealed that L. obliqua caterpillar bristle extract (LOCBE) displays a procoagulant activity that leads to intravascular thrombin formation, resulting in a special form of disseminated intravascular coagulation (DIC). Fibrinolysis seems to be secondary to the fibrin production, since no direct fibrinolytic activity was found in LOCBE. Two procoagulant toxins, a factor X activator (Losac) and a prothrombin activator (Lopap), were isolated from LOCBE and characterized. Infusion of Lopap into experimental animals triggered a condition similar to that observed in human envenomation.
Abstract in English:We studied and compared the effects of chloramphenicol antibiotic and garlic (Allium sativum), used as immunostimulants and growth promoters, on some physiological parameters, growth performance, survival rate, and bacteriological characteristics of Nile tilapia (Oreochromis niloticus). Fish (7±1g/fish) were assigned to eight treatments, with three replicates each. Treatment groups had a different level of Allium sativum (10, 20, 30, and 40g/kg diet) and chloramphenicol (15, 30, and 45mg/kg diet) added to their diets; the control group diet was free from garlic and antibiotic. Diets also contained 32% crude protein (CP) and were administered at a rate of 3% live body weight twice daily for 90 days. Results showed that the final weight and specific growth rate (SGR) of O. niloticus increased significantly with increasing levels of Allium sativum and chloramphenicol. The highest growth performance was verified with 30g Allium sativum / kg diet and 30mg chloramphenicol / kg diet. The lowest feed conversion ratio (FCR) was observed with 30g Allium sativum / kg diet and 30mg chloramphenicol / kg diet. There were significant differences in the protein efficiency ratio (PER) with all treatments, except with 45mg chloramphenicol / kg diet. No changes in the hepatosomatic index and survival rate were observed. Crude protein content in whole fish increased significantly in the group fed on 30g Allium sativum / kg diet, while total lipids decreased significantly in the same group. Ash of whole fish showed significantly high values with 30g Allium sativum and 15mg chloramphenicol / kg diet while the lowest value was observed in the control group. Blood parameters, erythrocyte count (RBC), and hemoglobin content in fish fed on diets containing 40g Allium sativum and all levels of chloramphenicol were significantly higher than in control. Significantly higher hematocrit values were seen with 30 and 45mg chloramphenicol / kg diet. There were no significant differences in the mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC). Plasma glucose decreased significantly with increasing levels of Allium sativum but increased significantly with increasing levels of chloramphenicol. Total lipids were significantly reduced with diets containing 40g Allium sativum and 30mg chloramphenicol / kg diet, while total plasma protein content was significantly higher in fish fed on diets containing 10, 20, and 30g Allium sativum, and 30 and 45mg chloramphenicol / kg diet. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities in plasma decreased significantly with increasing levels of Allium sativum and chloramphenicol. All Allium sativum and chloramphenicol levels decreased total bacteria and coliforms in water, muscles and intestine when compared to the control group. Treated groups had lower mortality rate than the control group during the challenge test. In conclusion, it can be suggested that adding 3% Allium sativum to fish diet can promote growth, reduce total bacteria, and improve fish health.
Abstract in English:Detection of Toxoplasma gondii (T. gondii) DNA in blood can help to diagnose the disease in its acute phase; however, it must be considered that hemoglobin, present in blood, can inhibit polymerase activity, making impracticable the detection of DNA in samples. Mice were experimentally infected via oral route with ME49 and BTU2 strains cysts and RH strain tachyzoites; polymerase chain reaction was used to detect T. gondii DNA in mice sera 18, 24, 48, 96, and 192 hours post infection (PI). Toxoplama gondii DNA was detected in only one animal infected with BTU2 strain, genotype III (isolated from a dog with neurological signs) 18 hours PI. The agent's DNA was not detected in any sample of the other experimental groups. New studies must be carried out to verify the technique sensitivity in researches on this agent's genetic material using sera samples of acute-phase toxoplasmosis patients, especially in cases of immunosuppression.
Abstract in English:Australian funnel-web spiders are relatively large primitive hunting spiders. Male Atrax robustus spiders have been responsible for a number of human deaths. Venom was collected from the species Hadronyche infensa (Hickman) [female], H. formidabilis [male and female], H. versuta [female], and A. robustus (Cambridge) [male] and was fractionated by high performance liquid chromatography. This resulted in the isolation and purification of a homologous series of 7 insecticidal peptides of relatively low molecular mass (approximately 4kDa). The amino acid sequences of these toxins consisted of 36 or 37 amino acids and were named atracotoxins. For the major bioassay of these toxins, we used the cotton bollworm, Helicoverpa armigera (Hubner), due to the great damage it causes to crops worldwide. These toxins, when injected subcutaneously into fifth or sixth instar larvae of Helicoverpa armigera,were lethal or caused an apparently irreversible writhing. The toxin from H. versuta venom showed no significant toxicity when subcutaneously injected into newborn mice. One of the toxins was found to have a free acid carboxyl terminus. These toxins have great potential as lead compounds for insecticide design or for incorporation in recombinant baculovirus insecticides.
Abstract in English:The objective of this paper was to evaluate the hepatobiliary function of patients with pulmonary tuberculosis under triple treatment, using the technetium-99m-DISIDA (99mTc-DISIDA) hepatobiliary scintigraphy. Ten men and three women with pulmonary tuberculosis were subjected to hepatobiliary scintigraphy at the beginning of triple treatment (M1) and two months after it (M2). Patients were from the urban area, of low socioeconomic level, malnourished, and chronic alcohol and/or tobacco users. Ten normal individuals were evaluated as controls. Radiotracer images were acquired on a computerized gamma camera (Orbiter-Siemens) and T1/2 uptake and excretion values were calculated. Nutritional status and serum hepatic enzyme levels for each patient were evaluated at M1 and M2. None presented clinical or laboratory antecedent of hepatobiliary disease. At M1, there were no hepatic serum or kinetic alterations of the 99mTc-DISIDA. At M2, patients presented better nutritional conditions than at M1; there was increased serum aspartate aminotransferase (AST) and reduced excretion time for 99mTc-DISIDA, which was interpreted as a more adaptive than toxic phenomenon, yet not all alterations were significant and none manifested clinically. Apparently, triple treatment acted on the liver inducing the P450 cytochrome enzymatic system, accelerating radiotracer excretion, which follows the same path as the bilirubins.
Abstract in English:Extracted venoms from two species of cubozoan, Chironex fleckeri (C. fleckeri)and Chiropsalmus sp., were injected into the freshwater crayfish Cherax quadricarinatus (C. quadricarinatus). By means of a Vascular Doppler, the cardiac parameters heart rate and contraction amplitude were recorded, with the theoretical total heart output calculated from these two recordings. Cherax quadricarinatus reflects prey items utilized by these two species in the wild and so comparisons of venom action on this animal have greater ecological relevance than those of previous mammalian models used. While the results of this study reflect previous research showing that the overall potency of C. fleckeri venom is greater than that of Chiropsalmus sp. venom, the action of the venoms on the heart muscle is found to be different. Chironex fleckeri,which has the most potent venom out of these two species, is actually less effective in reducing cardiac activity than Chiropsalmus sp., which may be a direct reflection of the variation in primary prey utilized by each species.
Abstract in English:Oxidative stress and proteases have been implicated in several diseases and extensive evidence indicates that antioxidants and protease inhibitors help prevent organ functional damage. Leiurus quinquestriatus (LQQ) scorpion venom causes cellular injuries that may lead to multiple organ failure. Thus, the capability of the antioxidant "natural standardized extract of Gingko biloba leaves (Gin, EGb 761)" and the non-selective protease inhibitor, aprotinin, in ameliorating venom-induced biochemical alterations indicative of cellular injury and oxidative stress was studied to determine their effectiveness in protecting rats from venom-evoked cellular damages. Thus, in this study, rats were treated with LQQ venom (0.3mg.kg-1, subcutaneously) alone or after Gin (150mg.kg-1, orally, daily for 2 weeks before venom) and/or aprotinin (Apr, 46000 KIU.kg-1, intraperitoneally, 30 min before venom). Control groups were injected with saline or treatment modalities. Lungs and hearts were excised after decapitating rats (n=8/group) 60 min after venom injection and the following activities were measured: reduced glutathione (GSH), malondialdehyde (MDA) - an index of lipid peroxidation, glutathione peroxidase (GPx), glucose-6-phosphate dehydrogenase (G6PD), and lactate dehydrogenase (LDH). Our findings demonstrate that LQQ venomsignificantly elevated GSH (p<0.05 vs. control), MDA (p<0.05), G6PD (p<0.05), and LDH activities (p<0.001) in hearts of envenomed rats. The venom also elevated MDA (p<0.05 vs. control) and reduced GSH and GPx (p<0.05) in the lungs of envenomed rats. In general, pretreatment with EGb761 attenuated LQQ venom-evoked increases in GSH (p<0.05 vs. venom), MDA in rat hearts and lungs (p<0.05 vs. venom), plus LDH in the heart (p<0.01). Aprotinin alone significantly reduced the venom-elicited increase in G6PD and LDH activities and the decrease in GPx levels (p<0.05). In general, these protective effects of EGb761 on GSH, MDA (p<0.01 vs. venom) and LDH (p<0.001) in the heart and/or lung were potentiated when combined with aprotinin. We concluded that the effectiveness of EGb761 and Apr in ameliorating venom-evoked biochemical changes indicative of necrosis and free radical generation point out the involvement of oxidative stress and proteases in venom-evoked cellular damages seen in this study in isolated rat hearts and lungs.
Abstract in English:The aim of this study was to investigate the antibacterial activity of propolis samples from Goiás, Paraná and São Paulo States, Brazil, and their flavonoids content. Ethanolic extracts of propolis (EEP) were prepared (30g of propolis in 70% ethanol), and the microorganisms Staphylococcus aureus and Escherichia coli were tested. The methodology employed was agar diffusion using filter paper discs. Ampicillin and tetracycline were used as controls. Antibacterial activity was determined by the reading of inhibition zone diameters (mm) after 24 hours incubation at 37°C. Results demonstrated that EEP inhibited the growth of Staphylococcus aureus but not that of Escherichia coli. Tetracycline and ampicillin showed an efficient action against both bacteria. Flavonoids content was variable, depending on the propolis sample. According to the results, it may be concluded that EEP showed effective action against Gram-positive bacteria, independently on their geographic origin, and a positive correlation between antibacterial activity and flavonoids content.
Abstract in English:The present work aimed to evaluate the clinical and hematological aspects during experimental envenomation by Crotalus durissus terrificus in dogs treated with different antiophidic serum doses. Sixteen dogs were divided into two groups of eight animals each. Group I received 1mg/kg venom subcutaneously and 30mg antiophidic serum intravenously; Group II received 1mg/kg venom subcutaneously and 60mg antiophidic serum intravenously. In the clinical evaluation, we observed ataxia, moderate sedation, dilated pupils, sialorrhea, flaccid paralysis of mandibular muscles, and discreet edema at the site of venom inoculation. Evaluating red and white blood cells, we observed a decrease of hemoglobins, globular volume and erythrocytes, and an increase of plasmatic proteins, leukocytes, neutrophils, monocytes and lymphocytes. Clotting time increased and there was blood incoagulability with return to normal clotting time six hours after antiophidic serum administration. Animals treated with six antiophidic serum flasks had a faster recovery than the animals that received three serum flasks.
Abstract in English:Scorpions are included in the order Scorpiones; class Arachnida. Lethal scorpions are mostly of the Buthidae family. Among these, species belonging to Androctonus, Leiurus and Mesobuthus genera cause most scorpion envenomations in Turkey. This study was performed aiming the production of antivenom by using Androctonus crassicauda telsons. Venom toxicity is related to telson weight, size, and storing condition (open or closed). Telsons of A. crassicauda were collected in Southeastern Anatolia (especially in Harran town, Sanliurfa), Turkey. They were separated according to weight, size, and storing condition - open (a) and closed (b). Venom solution was prepared by maceration of telsons. Swiss albino mice were used to determine the lethal dose 50% (LD50), which was as follows: Group 1a - 2.31mg; Group 1b - 2.66mg; Group 2a - 2.32mg; Group 2b - 2.66mg; Group 3a - 6.66mg; Group 3b - 6.88mg. Among the groups of telsons, the first and the second groups showed different characteristics. However, there were no differences between their toxicity. In the third group, a fourfold amount of telsons was used for toxicity. In other words, telsons weighting from 19.99 to 20mg (first group) and from 29.99 to 30mg (second group) presented similar LD50 values, and telsons weighting from 10 to 19.99mg (third group) showed a fourfold higher LD50 value. This difference was caused by the maturity of scorpions and venom toxicity was related to their size. The first and second groups were considered to be mature and the third group, not adult. Therefore, we can conclude that obtaining open telsons due to environmental factors was not effective for venom toxicity.
Abstract in English:Hymenoptera is a class of insects that sting in order to subdue their prey. Humans coming into accidental contact with these insects results in stings that may cause from mild local reaction like weal formation around the sting site to severe systemic reactions such as intravascular hemolysis, acute renal failure, pulmonary edema, cerebral edema, and rarely pancreatitis. We report here the clinical course of a patient who developed concurrent acute pancreatitis and pigment-induced acute renal failure after multiple hornet stings.