Previous studies have demonstrated that scorpion toxins increase the serum levels of IL-1, IL-6, INF-gamma, and GM-CSF in patients with severe shock and pulmonary edema. Moreover, it has been shown that experimental models of scorpion envenomation presented an increase in serum levels of IL-1, IL-6, IFN-gamma and nitric oxide. Thus, it is possible that the cytokine release may contribute to the onset and maintenance of the pulmonary edema induced by scorpion venom. This study was designed to investigate whether inflammatory and non-inflammatory cytokines, contribute to the pulmonary injury induced by infusion of Tityus serrulatus scorpion toxin in rats. We show that scorpion venom not only increases the expression of mRNA pulmonary inflammatory cytokines but also non-inflammatory cytokines as well. Moreover, the expression of IL-1alpha, IL-1beta and IL-6 mRNA was shown to be higher among the remaining detectable cytokines. The findings of this study provide additional insight towards the understanding of the pathophysiology of the pulmonary edema induced by scorpion venom. The increased level of pulmonary cytokines observed during the pulmonary edema may be responsible for the exacerbation and maintenance of the inflammatory response to scorpion venom in the lungs. 相似文献
Apis mellifera is a bee that was introduced to Brazil and has adapted very well to the climate conditions and vast diversity of plants that exist in the country. In the northeast region of Brazil, beekeepers make use of the association between bees and plants by selling various bee products, notably honey. One way to identify species visited by bees in an area is by the pollen in its products. Based on this, 16 samples of honey were analysed, which were collected over a period of two years and obtained from an apiary in the Atlantic Forest biome in the municipality of Entre Rios (Bahia). In addition, climatic data (precipitation and temperature) of the region were obtained for the months sampled. The average temperature of the region during the collection months varied from 22 to 28 °C. The highest precipitation recorded in the region was 133.7 mm3 and the lowest was 0.3 mm3. Seventy pollen types were found. The family Fabaceae was notable, with ten pollen types, of which Mimosa pudica was the most important with a high frequency of occurrence and distribution. The Eucalyptus (Myrtaceae) pollen type also had a high frequency of occurrence and distribution. In addition, pollen types corresponding to species that supply nectar to bees were identified, which contributes to the large diversity of bee plants for Apis mellifera in the study area. 相似文献
About 30% of the total area of Lake Batata (Amazon) was impacted by the disposal of bauxite tailings originated from the process
of washing bauxite. This effluent, composed by fine particles of clay and water, settled on top of the natural sediment, originating
a new substratum with a different physical and chemical composition. This phenomenon created a new distinct habitat (impacted
sediment) influencing the benthic community. The aim of this study was to evaluate the impact of bioturbation by Campsurus notatus (Ephemeroptera: Polymitarcytidae) on potential gas fluxes in the sediment of natural and impacted areas of the lake. The
natural sediment had a significantly higher methane concentration when compared to the impacted one. In incubated sediment
cores, the presence of C. notatus nymphs resulted in a significant increase in oxygen consumption and methane and carbon dioxide release to the water column.
The effect of the presence of nymphs on methane was ambiguous. The C. notatus nymphs strongly decreased methane concentration in natural sediment samples, probably because of the enhancement of the oxic
sediment area. However, this effect was not observed in impacted samples. Finally, the new substratum of Lake Batata decreased
methane concentration in sediment and water column. C. notatus nymphs demonstrated to have a significant role on gas flux (methane and CO2) from sediment to water column as well as on oxygen consumption in Lake Batata, consequently influencing the carbon cycle
in this lake.
Handling editor: S. M. Thomaz 相似文献
Coccidian protozoan species recorded from flycatchers are few, but they have been described with a certain frequency in recent years. In this context, the present study describes a new Isospora sp. from sepia-capped flycatchers Leptopogon amaurocephalus Tschudi, 1846 captured in the Itatiaia National Park and in a reforestation area which is about 60 km away from the park boundaries, in addition to providing a molecular identification via sequencing of the mitochondrial cytochrome c oxidase subunit 1 gene. Isospora leptopogonin. sp. has oöcysts that are subspheroidal to ovoidal, measuring on average 22.0 × 19.7 μm, with a smooth, bi-layered wall, c.1.7 μm thick. The micropyle is delicate or inconspicuous. Oöcyst residuum is absent, but one to three polar granules are present. Sporocysts are lemon-shaped, measuring on average 14.7 × 9.3 μm, with a knob-like Stieda body and a rectangular to rounded sub-Stieda body. Sporocyst residuum is present, consisting of compactly bounded granules. Sporozoites are vermiform, with refractile bodies and nucleus. Isospora leptopogoni is different from other Isospora spp. mainly due to its lemon-shaped sporocysts, the presence of micropyle and details of Stieda and sub-Stieda bodies. Phylogenetic analysis placed I. leptopogoni close to other Isospora spp. recorded from phylogenetically related hosts and from the same biogeographic region. Finally, the recurrent finding of this coccidian species in the same L. amaurocephalus specimen in a specific locality in the Itatiaia National Park suggests that the dispersion of I. leptopogoni needs continuous transmissions between susceptible passerines as the area of movement of each L. amaurocephalus specimen appears to be quite small.
Schistosomiasis is an important parasitic disease worldwide that affects more than 207 million people in 76 countries and causes approximately 250,000 deaths per year. The best long-term strategy to control schistosomiasis is through immunization combined with drug treatment. Due to the ability of DNA vaccines to generate humoral and cellular immune responses, such vaccines are considered a promising approach against schistosomiasis. Sm29 and tetraspanin-2 (Sm-TSP2) are two proteins that are located in the S. mansoni tegument of adult worms and schistosomula and induce high levels of protection through recombinant protein immunization. In this study, we transfected BHK-21 cells with plasmids encoding Sm29, Sm-TSP2 or a chimera containing both genes. Using RT-PCR analysis and western blot, we confirmed that the DNA vaccine constructs were transcribed and translated, respectively, in BHK-21 cells. After immunization of mice, we evaluated the reduction in worm burden. We observed worm burden reductions of 17-22%, 22%, 31-32% and 24-32% in animals immunized with the pUMVC3/Sm29, pUMVC3/SmTSP-2, pUMVC3/Chimera and pUMVC3/Sm29 + pUMVC3/SmTSP-2 plasmids, respectively. We evaluated the humoral response elicited by DNA vaccines, and animals immunized with pUMVC3/Sm29 and pUMVC3/Sm29 + pUMVC3/SmTSP-2 showed higher titers of anti-Sm29 antibodies. The cytokine profile produced by the spleen cells of immunized mice was then evaluated. We observed higher production of Th1 cytokines, such as TNF-α and IFN-γ, in vaccinated mice and no significant production of IL-4 and IL-5. The DNA vaccines tested in this study showed the ability to generate a protective immune response against schistosomiasis, probably through the production of Th1 cytokines. However, future strategies aiming to optimize the protective response induced by a chimeric DNA construct need to be developed. 相似文献
At small spatial and temporal scales, genetic differentiation is largely controlled by constraints on gene flow, while genetic diversity across a species' distribution is shaped on longer temporal and spatial scales. We assess the hypothesis that oceanographic transport and other seascape features explain different scales of genetic structure of giant kelp, Macrocystis pyrifera. We followed a hierarchical approach to perform a microsatellite‐based analysis of genetic differentiation in Macrocystis across its distribution in the northeast Pacific. We used seascape genetic approaches to identify large‐scale biogeographic population clusters and investigate whether they could be explained by oceanographic transport and other environmental drivers. We then modelled population genetic differentiation within clusters as a function of oceanographic transport and other environmental factors. Five geographic clusters were identified: Alaska/Canada, central California, continental Santa Barbara, California Channel Islands and mainland southern California/Baja California peninsula. The strongest break occurred between central and southern California, with mainland Santa Barbara sites forming a transition zone between the two. Breaks between clusters corresponded approximately to previously identified biogeographic breaks, but were not solely explained by oceanographic transport. An isolation‐by‐environment (IBE) pattern was observed where the northern and southern Channel Islands clustered together, but not with closer mainland sites, despite the greater distance between them. The strongest environmental association with this IBE pattern was observed with light extinction coefficient, which extends suitable habitat to deeper areas. Within clusters, we found support for previous results showing that oceanographic connectivity plays an important role in the population genetic structure of Macrocystis in the Northern hemisphere. 相似文献
The goal of the present study was to characterize the semen quality of dogs naturally infected with Leishmaniachagasi, and treated with Allopurinol and Amphotericin B. Eight naturally infected and eight non-infected dogs were selected. Following semen collection, progressive motility, vigor, concentration and sperm morphology were evaluated. The seminal patterns in the treated animals were evaluated at the beginning (d0) and at days 30 (d30), 60 (d60) and 150 (d150) of treatment. The progressive motility at d0 (35.7 ± 22.3%) was less than that of the control group (77.8 ± 7.1%) (P < 0.05). The vigor was similar to the control group throughout the treatment (P > 0.05). The number of sperm/mL, sperm/ejaculate and sperm/kg of body weight was similar among groups (P > 0.05). The percentages of normal spermatozoa of infected and treated animals were similar throughout the treatment and to the control group (69.1 ± 8.7%) at d60 (37.5 ± 11.2%) and d150 (48.3 ± 10.8%) (P > 0.05), but smaller at d0 (22.7 ± 10.5%) and d30 (28.8 ± 15.9%) (P < 0.05). A greater percentage of acrosome damage was observed in the control group (3.1 ± 2.3%) compared to the d60 (0.1 ± 0.2%) (P < 0.05). The infected dogs had a greater percentage of principal piece defects at d60 (37.0 ± 6.3%) than the control group (16.8 ± 7.3%) (P < 0.05); and greater percentages of detached normal heads at d0 (28.7 ± 19.7%) and d30 (18.5 ± 18.5%) than the control group (0.4 ± 0.5%) (P < 0.05). This reduction in semen quality of the infected animals is suggestive of an epididymal dysfunction. Due to this poor semen quality, caution is recommended when using infected male dogs for reproductive purposes. 相似文献