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1.
White‐nose syndrome (WNS) has decimated hibernating bat populations across eastern and central North America for over a decade. Disease severity is driven by the interaction between bat characteristics, the cold‐loving fungal agent, and the hibernation environment. While we further improve hibernation energetics models, we have yet to examine how spatial heterogeneity in host traits is linked to survival in this disease system. Here, we develop predictive spatial models of body mass for the little brown myotis (Myotis lucifugus) and reassess previous definitions of the duration of hibernation of this species. Using data from published literature, public databases, local experts, and our own fieldwork, we fit a series of generalized linear models with hypothesized abiotic drivers to create distribution‐wide predictions of prehibernation body fat and hibernation duration. Our results provide improved estimations of hibernation duration and identify a scaling relationship between body mass and body fat; this relationship allows for the first continuous estimates of prehibernation body mass and fat across the species'' distribution. We used these results to inform a hibernation energetic model to create spatially varying fat use estimates for M. lucifugus. These results predict WNS mortality of M. lucifugus populations in western North America may be comparable to the substantial die‐off observed in eastern and central populations.  相似文献   

2.
β-defensins are a group of cysteine-rich cationic antimicrobial peptides that play antibacterial and antiviral roles in immune systems of vertebrates. Here, we report the cloning and identification of a β-defensin 3 cDNA sequence from the common carp (Cyprinus carpio L.). Sequence alignment and phylogenetic analysis indicated that this β-defensin 3 belonged to the BD-2 group of fish. Real-time PCR showed that the β-defensin 3 mRNA was expressed in all the tissues of normal common carp that we examined and was highly expressed in the spleen and gills. When challenged with Vibrio anguillarum, the expression level of common carp β-defensin 3 mRNA was quickly upregulated in various tissues. Our results indicate that the β-defensin 3 showed markedly high constitutive expression in the gills, and significantly upregulated expression in the hindgut of the common carp after infection, suggesting it plays an important role in the innate and mucosal immunity of common carp.  相似文献   

3.
Environmental Biology of Fishes - The bentfin devil ray (Mobula thurstoni) is a migratory elasmobranch species with a wide distribution range. Despite the recent increase in mobulid research,...  相似文献   

4.
Neural transplantation in experimental parkinsonism (PD) is limited by poor survival of grafted embryonic dopaminergic (DA) cells. In this proof-of-principle study we hypothesized that a first regular initial graft may create a “dopaminergic” environment similar to the perinatal substantia nigra and consequently stimulate a subsequent graft. Therefore, we grafted ventral mesencephalic neurons sequentially at different time intervals into the same target localization. Rats with a unilateral lesion of the dopamine neurons produced by injections of 6-hydroxydopamine (6-OHDA) received E14 ventral mesencephalon derived grafts into the DA-depleted striatum. In the control group we grafted all 6 deposits on the first day (d0). The other 4 groups received four graft deposits distributed over 2 implantation tracts followed by a second engraftment injected into the same site 3, 6, 14 and 21 days later. Quantitative assessment of the survival of tyrosine hydroxylase-immunoreactive neurons and graft volume revealed best results for those DA grafts implanted 6 days after the first one. In the present study, a model of short-interval sequential transplantation into the same target-site, so called “nest” grafts were established in the 6-OHDA rat model of PD which might become a useful tool to further elucidate the close neurotrophic and neurotopic interactions between the immediate graft vicinity and the cell suspension graft. In addition, we could show that the optimal milieu was established around the sixth day after the initial transplantation. This may also help to further optimize current transplantation strategies to restore the DA system in patients with PD.  相似文献   

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Hainan Eld’s deer (Cervus eldi hainanus) experienced a dramatic decline in the late 1960s through early 1970s and by 1976 only 26 deer remained in Datian of Hainan Island, China. Since then, conservation efforts have successfully rescued this deer from extinction. We employed 10 microsatellite DNA loci to index genetic variation in the one source (Datian) and two introduced populations (Bangxi and Ganshiling) and suggest implications for the conservation of the species. A total of 40 alleles at 10 loci were examined from 198 deer blood samples. The source population harbored all 40 alleles, while the Bangxi and Ganshiling translocated populations contained 24 and 26 alleles, respectively. The genetic variability was low (H e ≈ 0.33) for each of the three populations. No significant difference in genetic variability between the three populations was detected (P > 0.05); yet significant differentiation was found among the three populations. Our results suggest that founder effects and genetic drift have affected the two translocated populations. For conservation we recommend the three populations be managed as a meta-population. When establishing future reintroductions, the founder population should have a size larger than the original 26 founders in Datian population or be composed of a cohort of over 20 same-age individuals with 1:1 sex ratio. Genetic monitoring for both the source and translocated populations should be continuously conducted in order to assess the effectiveness of deer conservation in the future.  相似文献   

7.
Studies on terrestrial ecosystems in the high Arctic region have focused on the response of these ecosystems to global environmental change and their carbon sequestration capacity in relation to ecosystem function. We report here our study of the photosynthetic characteristics and biomass distribution of the dominant vascular plant species, Salix polaris, Dryas octopetala and Saxifraga oppositifolia, in the high Arctic tundra ecosystem at Ny-Alesund, Svalbard (78.5 degrees N, 11.5 degrees E). We also estimated net primary production (NPP) along both the successional gradient created by the proglacial chronosequence and the topographical gradient. The light-saturated photosynthesis rate (A (max)) differed among the species, with approximately 124.1 nmol CO(2) g(-1)leaf s(-1) for Sal. polaris, 57.8 for D. octopetala and 24.4 for Sax. oppositifolia, and was highly correlated with the leaf nitrogen (N) content for all three species. The photosynthetic N use efficiency was the highest in Sal. polaris and lowest in Sax. oppositifolia. Distributions of Sal. polaris and D. octopetala were restricted to the area where soil nutrient availability was high, while Sax. oppositifolia was able to establish at the front of a glacier, where nutrient availability is low, but tended to be dominated by other vascular plants in high nutrient areas. The NPP reflected the photosynthetic capacity and biomass distribution in that it increased with the successional status; the contribution of Sal. polaris reached as high as 12-fold that of Sax. oppositifolia.  相似文献   

8.
Molecular Biology Reports - Mitochondrial diseases include a wide group of clinically heterogeneous disorders caused by a dysfunction of the mitochondrial respiratory chain and can be related to...  相似文献   

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