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81.
Sporotrichosis occurs worldwide, and the metropolitan region of Rio de Janeiro, Brazil, is a main endemic area, with a large number of human and animal cases in the last 19 years. This mycosis is more frequently described in cats rather than in dogs. There are a limited number of oral antifungal agents for the treatment of sporotrichosis in animals. In this context, the effectiveness of terbinafine in the treatment of sporotrichosis in humans, as well as the promising results of in vitro susceptibility tests, inspired us to use this drug in the therapy of this mycosis in dogs. We reported for the first time the use of terbinafine in the treatment of two dogs with sporotrichosis caused by Sporothrix brasiliensis. Moreover, we provided an overview of therapeutic features of canine sporotrichosis cases reported since the 1960s. One of the dogs presented the fixed cutaneous form of the disease, while the other patient presented hyperemia of the nasal mucosa and respiratory signs only. Terbinafine showed high antifungal activity in vitro against the canine Sporothrix isolates. The dogs were successfully treated with terbinafine, with remission of all clinical signs initially presented. The current reports indicate that this drug can emerge as a therapeutic option for canine sporotrichosis.  相似文献   
82.
Many parasites infect multiple hosts, but estimating the transmission across host species remains a key challenge in disease ecology. We investigated the within and across host species dynamics of canine distemper virus (CDV) in grizzly bears (Ursus arctos) and wolves (Canis lupus) of the Greater Yellowstone Ecosystem (GYE). We hypothesized that grizzly bears may be more likely to be exposed to CDV during outbreaks in the wolf population because grizzly bears often displace wolves while scavenging carcasses. We used serological data collected from 1984 to 2014 in conjunction with Bayesian state‐space models to infer the temporal dynamics of CDV. These models accounted for the unknown timing of pathogen exposure, and we assessed how different testing thresholds and the potential for testing errors affected our conclusions. We identified three main CDV outbreaks (1999, 2005, and 2008) in wolves, which were more obvious when we used higher diagnostic thresholds to qualify as seropositive. There was some evidence for increased exposure rates in grizzly bears in 2005, but the magnitude of the wolf effect on bear exposures was poorly estimated and depended upon our prior distributions. Grizzly bears were exposed to CDV prior to wolf reintroduction and during time periods outside of known wolf outbreaks, thus wolves are only one of several potential routes for grizzly bear exposures. Our modeling approach accounts for several of the shortcomings of serological data and is applicable to many wildlife disease systems, but is most informative when testing intervals are short. CDV circulates in a wide range of carnivore species, but it remains unclear whether the disease persists locally within the GYE carnivore community or is periodically reintroduced from distant regions with larger host populations.  相似文献   
83.
A new coccidian species of the genus Isospora Schneider 1881 (Apicomplexa, Eimeriidae) is reported from a single specimen of chelid turtle, Platemys platycephala (Schneider, 1792), obtained in a flooded area of the Amazonian municipality of Altamira, in Pará State, northern Brazil. The oöcysts of Isospora platemysi n. sp. are subspheroidal, 19.0–24.0 × 22.5–18.5 (22.6 × 20.8) µm in size [length/width ratio 1.0–1.1 (1.1)], with a colourless wall, 1.0–1.9 (1.4) wide, with two smooth layers; polar granule is present, oöcyst residuum and micropyle are both absent. The sporocyst is ovoidal, 10.0–12.1 × 8.0–10.0 (11.0 × 9.1) µm [length/width ratio 1.1–1.3 (1.2), with a knob-like Stieda body. Sub-Stieda body is present, rounded irregular-trapezoidal; para-Stieda body is absent. Sporocyst residuum is dispersed and composed of granules of differing sizes. This is only the fifth record of Isospora in chelonians, and the first report of a coccidian parasite of the genus Platemys.  相似文献   
84.
Although a high intake of antioxidants may decrease the risk of developing cardiovascular diseases, under certain circunstances they may promote free radical generation and lipid peroxidation. The objectives of the present study were to determine the antioxidant effects of ascorbic acid (AA), dehydroascorbic acid (DHA) and flavonoids on LDL submitted to different degrees of oxidation. LDL was submitted to oxidation with CuCl2 (2.4 μM). Before or at different times after the propagation of the oxidation process, 28 μM (5 μg/ml) of either AA or DHA or 5 μg/mL flavonoids extract were added. Alpha-tocopherol, conjugated dienes, thiobarbituric acid reacting substances (TBARS) and LDL electrophoretic mobility were determined as indices of LDL oxidation. The presence of any of the three antioxidants from the onset of the incubation delayed the oxidation process. However, the addition of both DHA and flavonoids to the oxidation process when it was already initiated and alpha-tocopherol consumed, accelerated the oxidation. In contrast, AA delayed the oxidation process even when added after alpha-tocopherol was consumed. Nevertheless, it also accelerated LDL oxidation when added during the propagation phase of the oxidation process. In conclusion: although AA, DHA and flavonoids delay LDL oxidation when added before the initiation of the process, they accelerate the process if added to minimally oxidized LDL.  相似文献   
85.
86.
In the present work we studied the antinociceptive and antiedematogenic effects of a quinone fraction (QF) isolated from the heartwood of Auxemma oncocalyx Taub. The major constituent of QF, which represented around 80% of this fraction, was a terpenoid quinone named oncocalyxone A (1). Results show that QF (10 and 30 mg/kg body wt., i.p.) significantly inhibited paw edema induced by carrageenan at the second, third, and fourth hours. The effect was dose-dependent and long lasting, and QF was less effective orally. An antiedematogenic effect was also demonstrated in the dextran-induced paw edema. In this model, however, QF was somewhat less potent. QF (1 and 5 mg/kg body wt., i.p.) inhibited acetic acid-induced abdominal contractions in mice in a dose-dependent manner. In addition, QF (5 and 10 mg/kg body wt., i.p.) inhibited only the second phase (inflammatory) in the formalin test, and showed no effect in the hot-plate test in mice. The antinociceptive activity of QF was predominantly peripheral and independent of the opioid system. The observed effects of QF are, at least in part, probably due to the presence of oncocalyxone A (1).  相似文献   
87.
Many columnar cacti are bat pollinated. It has been suggested that this kind of pollination would be more important in tropical than in temperate regions where flowers are open only one night. Thrichocereus pasacana produces big and resistant white flowers. We analyzed flower characteristics, floral cycle, stigmatic receptivity, nectar production, pollen presence and floral visitors in a T. pasacana population at National Park Los Cardones (Salta, Argentina) in November 1997. Flower features were constant between individuals of the population. Flowers start opening at evening and anthesis time is from 18 to 40 hs. The estigma was receptive throughout the floral cycle. Anther dehiscence occurs with flower opening. Nectar production was highest between 18 to 24 hs. Although T. pasacana are open during the night, floral visitors are diurnal. The most frequent was Xylocopa sp. In the study area, nectarivorous bats were not detected. The morphological features of T. pasacana flowers were similar but bigger compared to other columnar cacti. Anthesis time was also longer while nectar production was lower. T. pasacana pollination at National Park Los Cardones is done by bees.  相似文献   
88.
Thiamine-responsive megaloblastic anemia (TRMA, also known as Rogers syndrome, OMIM 249270) is a rare autosomal recessive disorder characterized by a triad of megaloblastic anemia, diabetes mellitus, and sensorineural deafness. Patients respond, to varying degrees, to treatment with megadoses of thiamine. We have recently shown genetic linkage of the TRMA gene to a 16-centimorgan (cM) region on 1q23.2–1q23.3 based on the analysis of four large, inbred families of Alaskan, Italian, and Israeli-Arab origin. Here we narrow the TRMA interval down to 4 cM based on genetic recombination, homozygosity mapping, and linkage disequilibrium (highest LOD score of 12.5 at D1S2799, at a recombination fraction of 0). We provide further evidence that the TRMA gene is located in this region and confirm the homogeneity of the disease. In this analysis, we genotyped seven additional families of diverse ethnic origin (Pakistani, Indian, Italian, Brazilian, and Japanese), and analyzed additional markers in two previously reported families showing evidence of linkage disequilibrium in a large area of their haplotypes. The multi-system manifestations of TRMA suggest that thiamine has a pivotal role in a multiplicity of physiological processes. Mapping the TRMA gene and understanding the molecular basis of the disease might, thus, shed light on the role of thiamine in common disorders such as deafness, anemia, and diabetes. Received: 16 April 1998 / Accepted: 6 July 1998  相似文献   
89.
A case of primary nonsecretory plasmacytoma of the spleen is reported. On laparotomy and splenectomy a 920 g spleen was removed, measuring 16×14×6 cm. The cut surface of the entire spleen showed that the tumour occupied most of the splenic tissue. A bone marrow aspirate and trephine, skeletal survey showed no signs of myeloma. Biopsy of the liver and regional lymph nodes was normal. Immunocytochemistry of the splenic tumour showed positivity for pan-B and plasma cell markers. After splenectomy the patient was treated with chemotherapy according to protocol VBCMP (M2).  相似文献   
90.
Increasing plant diversity in agroecosystems (i.e. intercropping) has been widely accepted as a means of promoting conservation biological control of mites and insect pests. Nevertheless, the contribution from underlying mechanisms such as the provision of non‐prey alternative food (i.e. pollen and nectar) and shelter have not been properly disentangled; and additionally, it remains unexplored whether the performance of nocturnal and diurnal natural enemies is improved when provided with diverse plant communities. Using open field experiments and a greenhouse microcosm, we investigated whether intercropping collards with parsley could create shelter for natural enemies in the lower stratum (parsley), and whether or not nocturnal and diurnal natural enemies would carry out aphid biological control equally well in this increased plant diversity scenario (intercropping). The results showed that the shelter alone provided by the lower stratum/companion plants (parsley) mediated an increase in the abundance of natural enemies without involving the provision of non‐prey alternative food. However, the biological control of aphids exerted by nocturnal predators was negatively affected by intercropping. The lower stratum (parsley) appeared to hamper the ability of nocturnal predators to reach aphids more quickly on the collard host plants (higher stratum). In total, our findings indicate that intercropping non‐flowering companion plants is likely enough to mediate an increase of natural enemies via shelter provision. In addition, the results suggest that nocturnal predators, or non‐flying predators for that matter, are hampered by complex lower stratum vegetation. Thus, considering natural enemy behaviour and plant characteristics when designing polyculture systems are vital for attaining conservation biological control success.  相似文献   
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