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981.
Mucosal malignant melanoma (MMM) is a rare and aggressive tumor. Despite effective local therapies, tumor recurrence and metastasis remain frequent. The genetics of MMM remain incompletely understood. This study is aimed to identify actionable genetic alterations by next-generation sequencing. Fifteen MMM samples were analyzed by next-generation and Sanger sequencing. Gene copy number alterations were analyzed by MLPA. Mutation status was correlated with pERK, pAKT, and Ki-67 expression and follow-up data. Inactivating mutations and intragenic deletions in neurofibromatosis type-1 (NF1) were identified in 3 and 2 cases, respectively, (in total 5/15, 33%) and activating mutations in NRAS and KRAS (3/15, 20%) cases. Other mutated genes included CDKN2A, APC, ATM, MITF, FGFR1, and FGFR2. BRAF and KIT mutations were not observed. Cases with NF1 alterations tended to have worse overall survival. The mutational status was not associated with pERK, pAKT, or Ki-67 immunostaining. MMM carries frequent gene mutations activating the MAPK pathway, similar to cutaneous melanoma. In contrast, NF1 is the most frequently affected gene. Intragenic NF1 deletions have not been described before and may go undetected by sequencing studies. This finding is clinically relevant as NF1-mutated melanomas have worse survival and could benefit from therapy with immune checkpoint and MEK inhibitors.  相似文献   
982.
Limnology - Benthic macroinvertebrate assemblages are used to assess anthropogenic stressors and pressures globally—although considerable spatial and temporal variability in those assemblages...  相似文献   
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984.
SET domain bifurcated protein 1 (SETDB1) is a human histone-lysine methyltransferase which is amplified in human cancers and was shown to be crucial in the growth of non-small and small cell lung carcinoma. In addition to its catalytic domain, SETDB1 harbors a unique tandem tudor domain which recognizes histone sequences containing both methylated and acetylated lysines, and likely contributes to its localization on chromatin. Using X-ray crystallography and NMR spectroscopy fragment screening approaches, we have identified the first small molecule fragment hits that bind to histone peptide binding groove of the Tandem Tudor Domain (TTD) of SETDB1. Herein, we describe the binding modes of these fragments and analogues and the biophysical characterization of key compounds. These confirmed small molecule fragments will inform the development of potent antagonists of SETDB1 interaction with histones.  相似文献   
985.
In this study we tested the use of mucus from five species of Neotropical marine batoid elasmobranchs to extract genomic DNA for barcoding and phylogenetic analysis. The DNA from all individuals sampled was successfully amplified and sequenced for molecular barcode, allowing 99–100% accuracy to the species level. This method proved to provide reliable and good-quality DNA for barcoding and phylogenetic analysis of Neotropical elasmobranchs, through rapid handling and with low disturbance to animals.  相似文献   
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987.
988.
The butterfly Ascia monuste L. (Lepidoptera: Pieridae) is a specialist pest of brassica crops in neotropical regions where it significantly impacts crop production. Understanding the actual and potential distribution of the pest and its hosts in current and future climates may help government agencies to mitigate and manage potential incursions. Here, we use MaxEnt algorithm to model the current distribution of both A. monuste and its host, Brassica oleracea var. capitata L. (cabbage) and then model the likely impact of projected climate change (RCP 4.5 and 8.5 scenarios) on their potential future distributions. While A. monuste is currently restricted to the American continent, we show that under current conditions the potential distribution of both the butterfly and cabbage includes areas of Africa, Asia, Oceania and Europe to some extent. The annual temperature range and mean annual temperature were the strongest predictors of the distribution of both species. Under a projected climate change scenario, suitable areas in the tropical climate zone are expected to decrease for both species. However, in temperate regions, the suitable area for cabbage is expected to increase but will remain unsuitable for the pest. Our results highlight the need for strategies to prevent the introduction of A. monuste to other areas of the tropical climate zone and for the development of management practices in the neotropical region.  相似文献   
989.
Local adaptation can lead to significant differences in host use that may influence population growth and spread. Here, we test the potential for adaptation of one behavioural component (host acceptance) to lead to cross‐adaptation for a separate behavioural component (dispersal propensity) using the cowpea seed beetle, Callosobruchus maculatus. C. maculatus originating from the same source population were subjected to selection for host use by rearing them for over 40 generations on either the preferred host of the ancestral population, Vigna radiata, or a marginal host for the ancestral population, Cicer arietinum. Host acceptance was then assayed using four choice and no‐choice oviposition assays including a low‐quality host, Lens culinaris, a marginal host, C. arietinum, and two high‐quality hosts, V. radiata and V. unguiculata. Dispersal was assayed in interconnected arenas containing one of three different hosts: V. radiata, V. unguiculata or C. arietinum. As expected, differences in host acceptance were present, in this case consisting of greater acceptance of the lower quality hosts in the C. arietinum population, but no significant differences in host preference hierarchy. Dispersal propensity in the C. arietinum population was significantly lower than in the V. radiata population, despite the absence of any difference in selection pressures for dispersal. Furthermore, significant differences in dispersal propensity in arenas containing different hosts were present in the V. radiata population, but not in the C. arietinum population. Results highlight the need to consider local adaptation when developing management recommendations, even for behaviours for which selection pressures are not directly apparent.  相似文献   
990.
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