Abstract in English:The toxicity of deoxynivalenol, both intravenously and orally, was investigated in male and female BALB/c mice. Technetium-99m (99m Tc)-labeled deoxynivalenol was administered to mice by tail vein injection and orally dosed. Distribution of labeled deoxynivalenol at 26 hours was monitored by gamma-scintigraphy. In the evaluated organs, the accumulation of radioactive deoxynivalenol was correlated with the amount of radioactivity. In addition, the toxicity of deoxynivalenol was measured by biochemical assays followed by histopathological findings. Kidney and hepatic marker enzymes were significantly increased in intravenously administered deoxynivalenol as compared to orally treated mice. Intravenously treated mice showed severe damage in liver and kidney when compared to those orally exposed. Biodistribution of 99mTc-labeled deoxynivalenol differed between oral and intravenous treatment. In intravenously exposed mice, deoxynivalenol was distributed primarily in the liver and kidney whereas in oral exposure, it was found in the stomach and intestines after 26 hours. Deoxynivalenol toxicity, associated with its biodistribution and organ toxicity, was greatest where it had accumulated. The results show that the toxicity of deoxynivalenol is associated with organ accumulation.
Abstract in English:The geographic distribution of paracoccidioidomycosis (PCM) in the Brazilian state of São Paulo was evaluated in a retrospective study using secondary data from serological analyses, carried out by double immunodiffusion assay of patients with PCM suspicion, from January 1999 to May 2010. Sixty percent of 10,176 patients, from 239 cities, were serologically reactive to P. brasiliensis. The cities that showed the most serological reactivity among patients were São João da Boa Vista (85%), Piracicaba (75%), Sorocaba (73%), Campinas (72%) and São Paulo (62%). São Paulo state has an area of 248,209.4 km²; the climate is tropical and sub-tropical with annual temperatures between 18 and 24ºC, high rainfall (900 to 1800 mm/year), rainy summers and mild winters. It also features large areas composed of acidic soils, and is one of the greatest contributors to Brazilian agricultural production and, separately, the largest producer of orange juice and, the ninth greatest producer of soy and sugar cane and the fourth largest coffee producer. We suggest that the climatic characteristics associated with soil type and development of primary activities can contribute to the endemic potential of PCM in São Paulo state.
Abstract in English:There are very few microbiological data on wound infections following snakebites. The objective of this study was to investigate the treatment of secondary infection following snakebites in central Taiwan. Microbiological data and antibiotic sensitivity of wound cultures were retrospectively analyzed from December 2005 to October 2007 in a medical center in central Taiwan. A total of 121 snakebite patients participated in the study. Forty-nine (40.5%) subjects were bitten by cobra (Naja atra); 34 of them had secondary infection, and 24 of them (70.6%) needed surgical intervention. Cobra bites caused more severe bacterial infection than other snakebites. Morganella morganii was the most common pathogen, followed by Aeromonas hydrophila and Enterococcus. Gram-negative bacteria were susceptible to amikacin, trimethoprim/sulfamethoxazole, cefotaxime, cefepime, ciprofloxacin, and piperacillin/tazobactam. Enterococcus were susceptible to ampicillin, gentamicin, penicillin and vancomycin. It is reasonable to choose piperacillin/tazobactam, quinolone, second- or third-generation cephalosporin for empirical therapy following snakebite. Surgical intervention should be considered for invasive soft tissue infections.
Abstract in English:Envenomation by Loxosceles bites is characterized by dermonecrotic and/or systemic features that lead to several clinical signs and symptoms called loxoscelism. Dermonecrotic lesions are preceded by thrombosis of the dermal plexus. Recent studies show that atheromatous plaque is prone to thrombosis due to endothelial cell apoptosis. To the best of our knowledge, there are no reports of microscopic dermal lesion and endothelial cell apoptosis induced by Loxosceles similis venom in the literature. Thus, the aim of the present study is to describe histological lesions induced by L. similis venom in rabbit skin and to elucidate whether apoptosis of endothelial cells is involved in the pathogenesis of loxoscelism. Forty male rabbits were split into two groups: the control group (intradermally injected with 50 µL of PBS) and the experimental group (intradermally injected with 0.5 µg of L. similis crude venom diluted in 50 µL of PBS). After 2, 4, 6 and 8 hours of injection, skin fragments were collected and processed for paraffin or methacrylate embedding. Sections of 5 µm thick were stained by HE, PAS or submitted to TUNEL reaction. Microscopically, severe edema, diffuse heterophilic inflammatory infiltrate, perivascular heterophilic infiltrate, thrombosis, fibrinoid necrosis of arteriolar wall and cutaneous muscle necrosis were observed. Two hours after venom injection, endothelial cells with apoptosis morphology were evidenced in the dermal plexus. Apoptosis was confirmed by TUNEL reaction. It seems that endothelial cell apoptosis and its consequent desquamation is an important factor that induces thrombosis and culminates in dermonecrosis, which is characteristic of cutaneous loxoscelism.
Abstract in English:In Mexico, medicinal plants are widely used. The use of Randia aculeata by healers against snakebites has never been scientifically tested in relation to possible effects on blood parameters and muscle tissue damage. Interviews were carried out in Jamapa, Veracuz, Mexico, with local residents to collect information about the traditional use of Randia aculeata. In this locality, seven pieces of fruit from the plant are mixed in a liter of alcohol, and then administered orally against snakebites. By using histological techniques and a murine model, we explored its cytoprotective properties against the effects of Crotalus simus and Bothrops asper venoms. Possible protections provided by the plant against tissue damage to skeletal and cardiac muscles and against the typical loss of red blood cells were analyzed. Randia aculeata caused an increase in microhematocrit and total hemoglobin, parameters that are often decremented in association with the loss of red blood cells, which is a characteristic effect of animal venom. Randia aculeata was also shown to protect against the lowering of platelet levels caused by Bothrops asper venom. Finally, Randia aculeata produced a partial inhibition of necrosis following administration of snake venom in skeletal and myocardial muscles. The present results provide solid evidence for the traditional use of Randia aculeata against snakebites, as demonstrated by protection against muscular tissue damage and the diminution of red blood cells.
Abstract in English:Clinical and laboratory changes were evaluated in rabbits after intoxication by Amorimia rigida, a plant that causes sudden death. Nine New Zealand male rabbits, averaging 3.54 kg, were categorized into three groups (n = 3) and received, for eight consecutive days, the equivalent of 30 g/kg dry matter of A. rigida water-soluble (SG) and water-insoluble (IG) extracts via nasoesophageal route. The control group received water. There were no alterations in creatine kinase enzyme (CK), CK myocardial fraction (CKMB) or troponine I (cTnI). None of the animals had clinical or electrocardiographic (conventional and Holter) alterations. There were progressive decreases in the left ventricular ejection fraction and systolic fractional shortening. Doppler echocardiography alterations suggested a systolic dysfunction in the SG and IG groups and diastolic dysfunction in IG group. It was concluded that the soluble and insoluble extracts of A. rigida cause deficit of cardiac function.
Abstract in English:Snake venoms are rich sources of active proteins that have been employed in the diagnosis and treatment of health disorders and antivenom therapy. Developing countries demand fast economical downstream processes for the purification of this biomolecule type without requiring sophisticated equipment. We developed an alternative, simple and easy to scale-up method, able to purify simultaneously protease and phospholipase A2 toxins from Bothrops alternatus venom. It comprises a multiple-step partition procedure with polyethylene-glycol/phosphate aqueous two-phase systems followed by a gel filtration chromatographic step. Two single bands in SDS-polyacrylamide gel electrophoresis and increased proteolytic and phospholipase A2 specific activities evidence the homogeneity of the isolated proteins.
Abstract in English:Although it is a frequent accident in a few countries, scorpion envenomation during pregnancy remains scarcely studied. In the present study, the effects of repetitive maternal exposure to Buthus occitanus tunetanus venom are investigated and its possible embryotoxic consequences on rats. Primigravid rats received a daily intraperitoneal dose of 1 mL/kg of saline solution or 300 µg/kg of crude scorpion venom, from the 7th to the 13th day of gestation. On the 21st day, the animals were deeply anesthetized using diethyl-ether. Then, blood was collected for chemical parameter analysis. Following euthanasia, morphometric measurements were carried out. The results showed a significant increase in maternal heart and lung absolute weights following venom treatment. However, the mean placental weight per rat was significantly diminished. Furthermore, blood urea concentration was higher in exposed rats (6.97 ± 0.62 mmol/L) than in those receiving saline solution (4.94 ± 0.90 mmol/L). Many organs of venom-treated rat fetuses (brain, liver, kidney and spleen) were smaller than those of controls. On the contrary, fetal lungs were significantly heavier in fetuses exposed to venom (3.2 ± 0.4 g) than in the others (3.0 ± 0.2 g). Subcutaneous blood clots, microphthalmia and total body and tail shortening were also observed in venom-treated fetuses. It is concluded that scorpion envenomation during pregnancy potentially causes intrauterine fetal alterations and growth impairment.
Abstract in English:Sol i 2 is a potent allergen in Solenopsis invicta venom, and most humans exhibit reactivity to it. The Sol gem 2 allergen found in the venom of the Thai tropical fire ant Solenopsis geminata was analysed in the present study. The protein was present in higher amounts than other proteins, as determined by SDS-PAGE, and presumably has allergenic properties similar to those of Sol i 2. Sol gem 2 molecular weight is 28 and 15 kDa, respectively, under non-reducing and reducing conditions, indicating that its native form is a dimer. LC-MS/MS analysis confirmed its similarity to Sol i 2. The mono/dimeric form of Sol gem 2 was determined to be relevant by proteomic approach and immunoblotting. An anti-Sol gem 2 antibody was produced in mice, with a titer greater than 1:800 according to the Western blotting analysis. The Sol gem 2-neutralising activity of this antibody was determined in crickets. The paralytic dose 50 (PD50) of crude S. geminata venom was elevated from 0.18 mg/g of body weight to more than 0.90 mg/g of body weight after preincubation with antibody at a ratio of 1:1. These results suggest that Sol gem 2 plays an important role in mediating the effects of the piperidine derivatives in the venom.
Abstract in English:Yeasts are becoming a common cause of nosocomial fungal infections that affect immunocompromised patients. Such infections can evolve into sepsis, whose mortality rate is high. This study aimed to evaluate the viability of Candida species identification by the automated system Vitek-Biomerieux (Durham, USA). Ninety-eight medical charts referencing the Candida spp. samples available for the study were retrospectively analyzed. The system Vitek-Biomerieux with Candida identification card is recommended for laboratory routine use and presents 80.6% agreement with the reference method. By separate analysis of species, 13.5% of C. parapsilosis samples differed from the reference method, while the Vitek system wrongly identified them as C. tropicalis, C. lusitaneae or as Candida albicans. C. glabrata presented a discrepancy of only one sample (25%), and was identified by Vitek as C. parapsilosis. C. guilliermondii also differed in only one sample (33.3%), being identified as Candida spp. All C. albicans, C. tropicalis and C. lusitaneae samples were identified correctly.
Abstract in English:The first autochthonous case of American cutaneous leishmaniasis was reported in the Federal District in 1980, and the species involved in this type of leishmaniasis was unknown. This study aimed to identify the species that causes the disease in the Federal District and to investigate its clinical and epidemiological aspects. Between 2000 and 2007, 71 autochthonous cases of leishmaniasis were reported in the Federal District. Leishmania species were identified by means of direct immunofluorescence reactions using monoclonal antibodies and restriction fragment length polymorphism. The species of 40 (56.33%) out of 71 samples were identified. Thirty-six (90%) were identified as Leishmania (Viannia) braziliensis and four (10%) were identified as Leishmania (Leishmania) amazonensis. In this area, the disease had clinical and epidemiological characteristics similar to those found in other Brazilian regions.
Abstract in English:Whenever humans come in touch with the sea, they become vulnerable to risks, most frequently on account of invading a habitat that belongs to potentially harmful aquatic animals. World literature shows a growing number of incidents in recent years with marine stingrays, despite the fact that these animals only attack when harassed. This report describes an accident in which an amateur fisherman was injured by a marine stingray, probably of the Dasyatis family, on his left forearm. The puncture wound was highly painful and progressed to rhabdomyolysis. It is conjectured that lymphatic drainage, applied in an attempt to reduce edema and its complications, may have contributed to rebound increase in serum creatine kinase levels (CK) and, thus, has exacerbated the intensity of rhabdomyolysis. Therefore, as a measure of caution, lymphatic drainage should not enter current treatment protocols for similar cases, until new studies are performed in order to clarify this issue.
Abstract in English:In Italy reports of human envenomations by yellow sac spiders have been sporadic. Since increasing clinical information would improve understanding of the danger of yellow sac spiders to humans, we report the case of a 7-year-old child and her father bitten by a documented Cheiracanthium punctorium. They developed acute persistent pain with local skin signs and numbness, and required emergency treatment. The father recovered completely within 1 to 2 hours and the child within 3 to 4 days after treatment, probably as a result of spontaneous evolution. Clinicians should be aware of the risks and immediate management of spider bites.