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Primates - Forests affected by fragmentation are at risk of losing their primate populations over the long term. The impact of fragmentation on primate populations has been studied in several...  相似文献   
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Traditional medicine has been practised in Ghana for centuries with the majority of Ghanaians still patronising the services of traditional healers. Throughout Africa a large number of people use pangolins as a source of traditional medicine, however, there is a dearth of information on the use of animals in folk medicine in Ghana, in particular the use of pangolins. The aim of this study was to determine the prevalent use of pangolins and the level of knowledge of pangolin use among traditional healers in Ghana for the treatment of human ailments. Data was gathered from 48 traditional healers using semi-structured interviews on the traditional medicinal use of pangolin body parts in the Kumasi metropolis of Ghana. The cultural importance index, relative frequency of citation, informant agreement ratio and use agreement values were calculated to ascertain the most culturally important pangolin body part as well as the level of knowledge dissemination among traditional healers with regards pangolin body parts. Our study revealed that 13 body parts of pangolins are used to treat various medicinal ailments. Pangolin scales and bones were the most prevalent prescribed body parts and indicated the highest cultural significance among traditional healing practices primarily for the treatment of spiritual protection, rheumatism, financial rituals and convulsions. Despite being classified under Schedule 1 of Ghana’s Wildlife Conservation Act of 1971 (LI 685), that prohibits anyone from hunting or being in possession of a pangolin, our results indicated that the use of pangolins for traditional medicinal purposes is widespread among traditional healers in Ghana. A study on the population status and ecology of the three species of African pangolins occurring in Ghana is urgently required in order to determine the impact this harvest for traditional medical purposes has on their respective populations as current levels appear to be unmonitored and unsustainable.  相似文献   
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Arbuscular mycorrhizal fungi (AMF) are important members of the plant microbiome. They are obligate biotrophs that colonize the roots of most land plants and enhance host nutrient acquisition. Many AMF themselves harbor endobacteria in their hyphae and spores. Two types of endobacteria are known in Glomeromycota: rod-shaped Gram-negative Candidatus Glomeribacter gigasporarum, CaGg, limited in distribution to members of the Gigasporaceae family, and coccoid Mollicutes-related endobacteria, Mre, widely distributed across different lineages of AMF. The goal of the present study is to investigate the patterns of distribution and coexistence of the two endosymbionts, CaGg and Mre, in spore samples of several strains of Gigaspora margarita. Based on previous observations, we hypothesized that some AMF could host populations of both endobacteria. To test this hypothesis, we performed an extensive investigation of both endosymbionts in G. margarita spores sampled from Cameroonian soils as well as in the Japanese G. margarita MAFF520054 isolate using different approaches (molecular phylotyping, electron microscopy, fluorescence in situ hybridization and quantitative real-time PCR). We found that a single AMF host can harbour both types of endobacteria, with Mre population being more abundant, variable and prone to recombination than the CaGg one. Both endosymbionts seem to retain their genetic and lifestyle peculiarities regardless of whether they colonize the host alone or together. These findings show for the first time that fungi support an intracellular bacterial microbiome, in which distinct types of endobacteria coexist in a single cell.  相似文献   
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The blue wildebeest (Connochaetes taurinus) is distributed throughout southern and east Africa while the black wildebeest (Connochaetes gnou) is endemic to South Africa and was driven to near extinction in the early 1900s due to hunting pressure and disease outbreaks. Extensive translocation of both species throughout South Africa is threatening the genetic integrity of blue and black wildebeest. To effectively manage these species, genetic tools that can be used to detect hybrid individuals, identify genetically unique subpopulations and determine the levels of genetic diversity are required. In this study, 11 microsatellite markers were developed for wildebeest through next-generation sequencing. The microsatellite loci displayed 2.00–4.14 alleles, unbiased heterozygosity values ranged from 0.32 to 0.60 and observed heterozygosity values ranged from 0.26 to 0.52. The comparatively high level of polymorphism observed in the microsatellite markers indicates that these markers can contribute significantly to our knowledge of population genetic structure, relatedness, genetic diversity and hybridization in these species.  相似文献   
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Introgressive hybridization poses a threat to the genetic integrity of black wildebeest (Connochaetes gnou) and blue wildebeest (Connochaetes taurinus) populations in South Africa. Black wildebeest is endemic to South Africa and was driven to near extinction in the early 1900s due to habitat destruction, hunting pressure and disease outbreaks. Blue wildebeest on the other hand are widely distributed in southern and east Africa. In South Africa the natural distribution ranges of both species overlap, however, extensive translocation of black wildebeest outside of its normal distribution range in South Africa have led to potential hybridization between the two species. The molecular identification of pure and admixed populations is necessary to design viable and sustainable conservation strategies, since phenotypic evidence of hybridization is inconclusive after successive generations of backcrossing. The aim of this study was to assess levels of hybridization in wildebeest using both species-specific and cross-species microsatellite markers. Black wildebeest (157) and blue wildebeest (122) from provincial and national parks and private localities were included as reference material, with 180 putative hybrid animals also screened. A molecular marker panel consisting of 13 cross-species and 11 species-specific microsatellite markers was developed. We used a Bayesian clustering model to confirm the uniqueness of blue- and black wildebeest reference groups, assign individuals to each of the two clusters, and determine levels of admixture. Results indicated a clear partition between black wildebeest and blue wildebeest (the average proportions of membership to black wildebeest and blue wildebeest clusters were QI?=?0.994 and QI?=?0.955 respectively). From the putative hybrid samples, only five hybrid individuals were confirmed. However, high levels of linkage disequilibrium were observed in the putative hybrid populations which may indicate historical hybridization. Measures of genetic diversity in the black wildebeest populations were found to be lower than that of the blue wildebeest. The observed lower level of genetic diversity was expected due to the demographic history of the specie. This study will make a significant contribution to inform a national conservation strategy to conserve the genetic integrity of both species.  相似文献   
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Melatonin and its derivatives modulate the Plasmodium falciparum and Plasmodium chabaudi cell cycle. Flow cytometry was employed together with the nucleic acid dye YOYO-1 allowing precise discrimination between mono- and multinucleated forms of P. falciparum-infected red blood cell. The use of YOYO-1 permitted excellent discrimination between uninfected and infected red blood cells as well as between early and late parasite stages. Fluorescence intensities of schizont-stage parasites were about 10-fold greater than those of ring-trophozoite form parasites. Melatonin and related indolic compounds including serotonin, N-acetyl-serotonin and tryptamine induced an increase in the percentage of multinucleated forms compared to non-treated control cultures. YOYO-1 staining of infected erythrocyte and subsequent flow cytometry analysis provides a powerful tool in malaria research for screening of bioactive compounds.  相似文献   
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Background

In Huntington’s disease (HD), motor symptoms develop prior to the widespread loss of neurons in striatum and cerebral cortex. The aim of this study was to examine dysfunctional patterns of corticostriatal communication during spontaneously occurring behaviors in a transgenic mouse model of HD.

Methodology/Principal Findings

Local field potentials (LFPs) were recorded from two closely interconnected areas, motor cortex and dorsal striatum, in wild-type controls (WT, n = 14) and a widely used transgenic HD model (R6/2 mice, n = 12). All mice were between the ages of 7–9 weeks, a critical period of motor symptom development in R6/2s. Recordings were obtained while the mice were behaving freely in an open field. Specific LFP activity was extracted using timestamps for three increasingly demanding motor behaviors: 1) resting; 2) grooming; and 3) active exploration. Power spectral densities (PSD) were obtained for the cortical and striatal LFPs as well as coherence levels and relative phase across the frequency spectrum. In both brain regions, only R6/2s showed high frequency LFP oscillations during rest and grooming. As behavior increased from resting to exploring, corticostriatal synchrony at high frequencies declined in R6/2s, completely opposite to the WT pattern. R6/2s also exhibited nearly in-phase corticostriatal activity (cortex phase leads of ∼5°), while the WTs consistently showed cortical phase lags of ∼20° across all assessed behaviors, indicating a lead role for striatum.

Conclusions/Significance

Our results add to growing evidence for altered communication between cortex and striatum in HD and suggest more generally that increasingly demanding motor behaviors differentially modulate corticostriatal communication. Our data also suggest conduction delays in R6/2 corticostriatal transmission, leading to compensatory speeding of LFP activity, as evidenced by the presence of high frequency LFP oscillations.  相似文献   
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