Abstract in English:Rabies is a viral acute encephalitis of progressive and fatal outcome, particular of hot-blooded animals, and accidentally affecting men. Since it is a zoonosis with different animal species acting as a reservoir in the nature, this disease is a great public health problem in several countries in development. Prophylactic treatments for human rabies started in 1885 with Louis Pasteur, and developed in order to provide higher protection and lower incidence of side effects. Today, treatments of pre and post-exposure to the virus are well established, with excellent results of protection for individuals exposed to animals potentially contaminated by the rabies virus. These treatments consist of utilising the vaccine isolatedly or in combination with equine immunoglobulin, what contributes, in an important way, to the decrease in the number of cases of rabies.
Abstract in English:The pharmacological effects of Bothrops neuwiedi pauloensis venom on mouse phrenic nerve-diaphragm (PND) preparations were studied. Venom (20 mug/ml) irreversibly inhibited indirectly evoked twitches in PND preparations (60 ± 10% inhibition, mean ± SEM; p<0.05; n=6). At 50 mug/ml, the venom blocked indirectly and directly (curarized preparations) evoked twitches in mouse hemidiaphragms. In the absence of Ca2+, venom (50 mug/ml), produced partial blockade only after an 80 min incubation, which reached 40.3 ± 7.8% (p<0.05; n=3) after 120 min. Venom (20 mug/ml) increased (25 ± 2%, p< 0.05) the frequency of giant miniature end-plate potentials in 9 of 10 end-plates after 30 min and the number of miniature end-plate potentials which was maximum (562 ± 3%, p<0.05) after 120 min. During the same period, the resting membrane potential decreased from - 81 ± 1.4 mV to - 41.3 ± 3.6 mV 24 fibers; p<0.01; n=4) in the end-plate region and from - 77.4 ± 1.4 to -44.6 ± 3.9 mV (24 fibers; p<0.01; n=4) in regions distant from the end-plate. These results indicate that B. n. pauloensis venom acts primarily at presynaptic sites. They also suggest that enzymatic activity may be involved in this pharmacological action.
Abstract in English:The frequency of envenoming in Northwest counties of the Rio de Janeiro State, Brazil, from 1995 to 2000 was evaluated. Reports from the Municipal Secretariat of Health of these counties were used. The results demonstrated that, from 1997 to 1999, there was a shortage of notification, and 40 cases of envenomations caused by Bothrops snakes were registered. These cases were more common from February to October, and the lower limbs of male peasants were the mainly affected areas.
Abstract in English:The use of radiotracers allows the understanding of the bioavailability process, biodistribution, and kinetics of any molecule labelled with an isotope, which does not alter the molecule's biological properties. In this work, technetium-99m and iodine-125 were chosen as radiotracers for biodistribution studies in mice using bee (Apis mellifera) venom and a toxin (PnTX2-6) from the Brazilian "armed" spider (Phoneutria nigriventer) venom. Incorporated radioactivity was measured in the blood, brain, heart, lung, liver, kidney, adrenal gland, spleen, stomach, testicle, intestine, muscle, and thyroid gland. Results provided the blood kinetic parameter, and different organs distribution rates.
Abstract in English:This investigation was performed in order to assess the inflammatory response induced by Naja haje arabica venom (NhaV) in rat hind paw. The inflammatory response was estimated by measuring the edema with a Plethysmometer. The venom (0.625-10mug/paw) produced a dose and time-dependent increase in non-hemorrhagic paw edema. The response to NhaV was maximal within 15 min and disappeared in 24 h. Five mug/paw of NhaV was chosen to test the effect of various drugs on the edema induced by this venom. Quinacrine (QNC), a phospholipase A2 (PLA2) inhibitor, and dipyridamole (DPM), an adenosine transport inhibitor, attenuated venom-induced edema in rat paw (P<0.001). Commercially available antivenom was ineffective when administered intravenously, whereas its local administration with NhaV attenuated the edema formation (P<0.001). In conclusion, NhaV-induced edema in rat paw involves PLA2 and adenosine mechanisms. Additionally, the use of polyspecific antivenom, intravenously, was ineffective in preventing NhaV-induced edema.
Abstract in English:Copulation in Opisthogonimus fonsecai Ruiz & Leão, 1942 (Trematoda, Digenea, Plagiorchiidae), parasite of Bothrops moojeni Hoge, 1966 (Serpentes, Viperiade), was reported. Data on the histology of the cirrus and metraterm of the copulants were presented. Morphology of the cirrus was also examined by scanning electron microscopy.
Abstract in English:The direct effect of ethanolic extract of propolis on guinea pig lung cell suspension containing mast cells, as well as its influence on the histamine release induced by antigen (ovoalbumin 10 mug/ml) and ionophore A 23187 (3 muM) were investigated. Propolis ethanolic extract (300 mug/ml) increased the histamine release in guinea pig lung suspension containing mast cells by a cytotoxic effect. Lower concentrations of propolis had no effect on histamine release. Our results demonstrated that propolis (3, 10, 30, and 100 mug/ml) shows no significant effect on the histamine release induced by ionophore and antigen. Based on these results, we suggest that propolis could directly activate mast cells, promoting inflammatory mediators release by cytotoxic mechanisms, what could be related to allergic processes in propolis sensitive people.
Abstract in English:Rabies is a viral disease of mammals transmitted through the bite of a rabid animal. A frugivorous adult male bat, Artibeus lituratus, family Phyllostomidae, was diagnosed as positive to rabies by direct immunofluorescence (DIF) and mouse inoculation test (MIT) of the bat's brain, both performed at the School of Veterinary Medicine and Animal Husbandry - FMVZ, UNESP, Botucatu, São Paulo State, Brazil. The animal collided with the window of a commercial establishment in the urban area during the day. With regard to DIF, a high amount of Negri bodies of several sizes was observed in the brain. The spleen and right kidney presented some Negri bodies too. In relation to MIT, the mice presented paralysis in the 7th day, and died in the day after with several characteristic small bodies. The reverse transcriptase-polymerase chain reaction (RT-PCR), followed by hemi-nested RT-PCR (hnRT-PCR) resulted in an amplification of fragments from the bat's brain viral RNA, 432bp in RT-PCR, and 274bp in hnRT-PCR, confirming the diagnosis. Therefore, the hnRT-PCR and DIF have good sensitivity and specificity, providing and confirming the diagnosis of the clinical samples in a short period of time.