Venom of the giant ant Dinoponera quadriceps attenuates inflammatory pain in mouse cutaneous wound healing model

Arthropod venoms are potential sources of bioactive substances, providing tools for the validation of popular use and new drugs design. Ants belonging to the genus Dinoponera are used in the folk medicine to treat inflammatory conditions. It was previously demonstrated that the venom of the giant ant Dinoponera quadriceps (DqV), containing a mixture of polypeptides, elicit antinociceptive effect in mice models of chemical, mechanical and thermal nociception. The aim of this study was to evaluate DqV antiinflammatory and antihypernociceptive effects in a mice model of traumatic cutaneous wound. Colonies of D. quadriceps were collected in the ‘‘Serra de Maranguape’’ (State of Ceará, northeastern Brazil), a small mountain range located on the coastal zone, and the venom secreted by the ant glands was extracted with capillary tubes, further lyophilized and maintained at -20 ± 1ºC until use. Wounds were performed in the dorsum of Swiss mice. Animals received intravenous (i.v.) injection of DqV (50 µg -1kg day-1) during 3 days for evaluation of inflammatory parameters present in the wounds: hypernociception, leukocyte infiltrate, myeloperoxidase activity, nitrite nitrate-1 content. Data was tested by two-way ANOVA and Bonferroni’s post-hoc test. DqV reduced (2.7 folds) hypernociception at 48 hours, leukocyte infiltration by 65% at 6 hours and myeloperoxidase activity by 60% at 0.5 hour after wound induction. In conclusion, the venom extracted from D. quadriceps glands attenuates inflammation and hypernociception in mice cutaneous wounds.

[Head injuries in Duckburg in 1959 and 2009].

Comic books have been a part of popular culture through generations. Debates concerning their graphic depictions of violence have been ongoing for nearly as long. Our aim was to examine if the violence in "Donald Duck & Co." (a weekly published Danish comic book), illustrated through the number of head injuries, increased in the period from 1959 to 2009. The comic book vintages from the years 1959 and 2009 were read, and the number of head injuries noted. The head injuries were characterized by severity, in part by a modified Glasgow Coma Scale and in part by a newly developed Comic Book Coma Scale. The number of head injuries were equal in the examined years, however, the number of head injuries per page decreased from 1/10 pages to 1/20 pages. Donald Duck sustained a better part of the injuries increasing from 17% in 1959 to 33% in 2009. The study indicates that we, with peace of mind, can read a comic book while the rest of the family takes care of the dishes at Christmas.

Light damage as a model of retinal degeneration.

The induction of retinal degeneration by light exposure is widely used to study mechanisms of cell death. The advantage of such light-induced lesions over genetically determined degenerations is that light exposures can be manipulated according to the needs of the experimenter. Bright white light exposure can induce a synchronized burst of apoptosis in photoreceptors in a large retinal area which permits to study cellular and molecular events in a controlled fashion. Blue light of high energy induces a hot spot of high retinal irradiance within very short exposure durations (seconds to minutes) and may help to unravel the initial events after light absorption which may be similar for all damage regimens. These initial events may then induce various molecular signaling pathways and secondary effects such as lipid and protein oxidation, which may be varying in different light damage setups and different strains or species, respectively. Blue light lesions also allow to study cellular responses in a circumscribed retinal area (hot spot) in comparison with the surrounding tissue.Here we describe the methods for short-term exposures (within the hours range) to bright full-spectrum white light and for short exposures (seconds to minutes) to high-energy monochromatic blue or green light.

Genetic influences on secondary degeneration and wound healing following spinal cord injury in various strains of mice.

Various inbred strains of mice exhibit dramatic differences in sensitivity to excitotoxic cell death induced by systemic injections of kainic acid (KA). The present study evaluates whether the same strains are also differentially sensitive to secondary degeneration after spinal cord injury, in which excitotoxic cell death is thought to play a pathogenic role. Spinal cord crush injuries were produced at T9 in two inbred strains that are resistant to KA-induced excitotoxic cell death (C57Bl/6 and Balb/c) and four strains that are sensitive (CD-1, FVB/N, 129T2 Sv/EMS, and C57Bl/10). The spinal cord was prepared for light microscopy at intervals from 1 to 56 days postinjury, and the area of damaged tissue (termed lesion size) and amount of cavitation were determined by quantitative image analysis. Lesion size increased between 1 and 7 days in all strains and then decreased steadily in a wound-healing process that occurs uniquely in mice. The extent of cavitation also gradually decreased from 7 to 56 days in all strains. Although lesion area and cavitation decreased in all strains, there were significant differences in lesion size and cavitation across strains. Specifically, lesion areas in the KA-sensitive strains FVB/N, 129T2 Sv/EMS, and CD-1 were significantly larger at 56 days postinjury than in the KA-resistant strains C57Bl/6 and Balb/c. We conclude that the genetic differences that confer resistance and sensitivity to KA-induced neurotoxicity also modify the secondary degenerative processes that occur after spinal cord injury, so that resistance to excitotoxic injury leads to smaller overall lesions and a more effective wound-healing response.

Lesines locales y sistemicas inducidas por veneno de Bothrops alternatus (víbora de la cruz) de Argentina / Local and sistemic lesions induced by Bothrops alternatus venom (víbora de la cruz) of Argentine

Se inocularon ratas de 220+= 20 g de peso, en grupos de 5 animales, con 800 ug de veneno de Bothrops alternatus de Argentina desecado y homogeneizado, diluído en 0,1 ml de solución salina, pore via intramuscular. Para la obtención de sangre y su posterior sacrificio, se anestesiaron a las 3, 9 y 24 horas, tomándose muestras del músculo inoculado, hígado y riñón. Se realizaron determinaciones enzimáticas y los tejidos se procesaron para histopatología. A las 3 horas, se observaron necrosis de fibras musculares confirmadas por métodos histoquímicos, hemorragia e infiltrado inflamatorio, los que se intensificaron a las 9 y 24 horas. Paralelamente se observó un incremento plasmático de lñas actividades enzimáticas de creatin fosfoquinasa (CPK), aspartato aminotransferasa (AST) y la alanina aminotransferasa (ALT); siendo máximo el aumento de CPK entre las 3 y 9 horas. La respuesta inflamatoria estudiada en ratón, mostró una reacción rápida cuya recuperación fue lenta. La necrosis de fibras musculares fue acompañada por peroxidación de lípidos y precipitación de calcio en las células. Las lesiones de te4jido hepático no fueron relevantes y en riñón se detectaron alteraciones en zona yuxtamedular y en el intersticio cortical

Lesines locales y sistemicas inducidas por veneno de Bothrops alternatus (víbora de la cruz) de Argentina / Local and sistemic lesions induced by Bothrops alternatus venom (víbora de la cruz) of Argentine

Se inocularon ratas de 220+= 20 g de peso, en grupos de 5 animales, con 800 ug de veneno de Bothrops alternatus de Argentina desecado y homogeneizado, diluído en 0,1 ml de solución salina, pore via intramuscular. Para la obtención de sangre y su posterior sacrificio, se anestesiaron a las 3, 9 y 24 horas, tomándose muestras del músculo inoculado, hígado y riñón. Se realizaron determinaciones enzimáticas y los tejidos se procesaron para histopatología. A las 3 horas, se observaron necrosis de fibras musculares confirmadas por métodos histoquímicos, hemorragia e infiltrado inflamatorio, los que se intensificaron a las 9 y 24 horas. Paralelamente se observó un incremento plasmático de lñas actividades enzimáticas de creatin fosfoquinasa (CPK), aspartato aminotransferasa (AST) y la alanina aminotransferasa (ALT); siendo máximo el aumento de CPK entre las 3 y 9 horas. La respuesta inflamatoria estudiada en ratón, mostró una reacción rápida cuya recuperación fue lenta. La necrosis de fibras musculares fue acompañada por peroxidación de lípidos y precipitación de calcio en las células. Las lesiones de te4jido hepático no fueron relevantes y en riñón se detectaron alteraciones en zona yuxtamedular y en el intersticio cortical(AU)

Ectopic osteomyelogenous response to demineralized bone matriz implant in busulphan treated mice

Camundongos Swiss, fêmeas, (25-30 g; n = 100) receberam 4 injeçöes de bussulfano (20 mg/kg, ip) a intervalos de 15 dias (n = 100). Antes do tratamento e após 30, 60 e 90 dias, os animais deste e de um grupo controle (n = 15) foram avaliados quanto ao leucograma, taxa de hemoglobina e hematócrito por meio do sangue colhido por punçäo retroorbital. Sessenta dias após o início do tratamento, 60 animais sobreviventes do grupo tratado e 15 animais do grupo controle receberam implantes intermusculares de matriz óssea desmineralizada (MOD-10 mg). No 90§ dia (30 dias após o implante) foram sacrificados para exame histológico da medula óssea esternal (MOE) e da resposta osteomielogênica ao implante de MOD. Trinta dias após o início do tratamento observou-se leucopenia, com diminuiçäo do número de granulócitos, linfócitos e monócitos nos animais que receberam bussulfano. O hematócrito e a taxa de hemoglobina apresentaram-se diminuídos no 60§ dia. O exame histológico da MOE do grupo tratado revelou hipocelularidade, dilataçäo dos capilares sinusóides e reduçäo do número de megacariócitos (50 por cento). Os animais controle apresentaram 100 por cento de resposta positiva ao implante de MOD, havendo formaçäo de placas metaplásicas compostas por trabéculas ósseas contendo cavitaçöes preenchidas por células hematopoiéticas. Em 46,7 por cento dos animais tratados observou-se resposta osteomielogênica semelhante à do grupo controle, mas com hipocelularidade e maior componente de adipócitos; 25 por cento apresentaram resposta osteomielogênica tardia e incompleta com menor componente ósseo, maior componente cartilaginoso e ausência de células hematopoiéticas; nos 28,3 por cento restantes a resposta foi negativa