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Journal of Physiology and Biochemistry - The product of Aoc3 gene is known as vascular adhesion protein-1 (VAP-1), a glycoprotein contributing to leukocyte extravasation and exhibiting...  相似文献   
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Peili Gu  Sandy Chang 《Aging cell》2013,12(6):1100-1109
Coats plus is a rare recessive disorder characterized by intracranial calcifications, hematological abnormalities, and retinal vascular defects. This disease results from mutations in CTC1, a member of the CTC1–STN1–TEN1 (CST) complex critical for telomere replication. Telomeres are specialized DNA/protein structures essential for the maintenance of genome stability. Several patients with Coats plus display critically shortened telomeres, suggesting that telomere dysfunction plays an important role in disease pathogenesis. These patients inherit CTC1 mutations in a compound heterozygous manner, with one allele encoding a frameshift mutant and the other a missense mutant. How these mutations impact upon telomere function is unknown. We report here the first biochemical characterization of human CTC1 mutations. We found that all CTC1 frameshift mutations generated truncated or unstable protein products, none of which were able to form a complex with STN1–TEN1 on telomeres, resulting in progressive telomere shortening and formation of fused chromosomes. Missense mutations are able to form the CST complex at telomeres, but their expression levels are often repressed by the frameshift mutants. Our results also demonstrate for the first time that CTC1 mutations promote telomere dysfunction by decreasing the stability of STN1 to reduce its ability to interact with DNA Polα, thus highlighting a previously unknown mechanism to induce telomere dysfunction.  相似文献   
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Maize represents one of the main cultivar for food and energy and crop yields are influenced by soil physicochemical and climatic conditions. To study how maize plants influence soil microbes we have examined microbial communities that colonize maize plants grown in carbonate‐rich soil (pH 8.5) using culture‐independent, PCR‐based methods. We observed a low proportion of unclassified bacteria in this soil whether it was planted or unplanted. Our results indicate that a higher complexity of the bacterial community is present in bulk soil with microbes from nine phyla, while in the rhizosphere microbes from only six phyla were found. The predominant microbes in bulk soil were bacteria of the phyla Acidobacteria, Bacteroidetes and Proteobacteria, while Gammaproteobacteria of the genera Pseudomonas and Lysobacter were the predominant in the rhizosphere. As Gammaproteobacteria respond chemotactically to exudates and are efficient in the utilization of plants exudate products, microbial communities associated to the rhizosphere seem to be plant‐driven. It should be noted that Gammaproteobacteria made available inorganic nutrients to the plants favouring plant growth and then the benefit of the interaction is common.  相似文献   
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Children in dentistry are traditionally described in terms of medical diagnosis and prevalence of oral disease. This approach gives little information regarding a child’s capacity to maintain oral health or regarding the social determinants of oral health. The biopsychosocial approach, embodied in the International Classification of Functioning, Disability and Health - Child and Youth version (ICF-CY) (WHO), provides a wider picture of a child’s real-life experience, but practical tools for the application of this model are lacking. This article describes the preliminary empirical study necessary for development of such a tool - an ICF-CY Core Set for Oral Health. An ICF-CY questionnaire was used to identify the medical, functional, social and environmental context of 218 children and adolescents referred to special care or paediatric dental services in France, Sweden, Argentina and Ireland (mean age 8 years ±3.6yrs). International Classification of Disease (ICD-10) diagnoses included disorders of the nervous system (26.1%), Down syndrome (22.0%), mental retardation (17.0%), autistic disorders (16.1%), and dental anxiety alone (11.0%). The most frequently impaired items in the ICF Body functions domain were ‘Intellectual functions’, ‘High-level cognitive functions’, and ‘Attention functions’. In the Activities and Participation domain, participation restriction was frequently reported for 25 items including ‘Handling stress’, ‘Caring for body parts’, ‘Looking after one’s health’ and ‘Speaking’. In the Environment domain, facilitating items included ‘Support of friends’, ‘Attitude of friends’ and ‘Support of immediate family’. One item was reported as an environmental barrier – ‘Societal attitudes’. The ICF-CY can be used to highlight common profiles of functioning, activities, participation and environment shared by children in relation to oral health, despite widely differing medical, social and geographical contexts. The results of this empirical study might be used to develop an ICF-CY Core Set for Oral Health - a holistic but practical tool for clinical and epidemiological use.  相似文献   
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Although there is a wide consensus on the efficacy of paratuberculosis vaccination to limit economic losses, its use has been restricted because of its interference in the diagnosis of tuberculosis. Data from a vaccine clinical trial in the Basque Country (Spain) has been evaluated in relationship with bovine tuberculosis intradermal test results. The trial included two herds applying a Test and Culling strategy and five applying an inactivated vaccine. The vaccine was applied to animals of all ages present in each vaccinated herd when joining the trial, and then to all the replacers within their first three months of life. Yearly testing done with the comparative intradermal test (CIT) was applied to all animals older than 6 weeks. Between 2005 and 2011, the study generated 2,033 records from Vaccinated Herds (VH) and 2,252 from Test and Cull herds (TC). Pre-vaccination positive results rate was 2.40% among the 7 herds in the single bovine intradermal tuberculin test (BSIT). Two years later it rose to 20.42% in the VH and remained below at 0.75% in the TC. Applying the CIT reduced these rates to only 0.58% in the VH and to 0.25% in the TC ons. Regarding time since each animal joined the program, the proportion of positives to BSIT was variable and, in some cases, significantly different between time points. With regard to the age of vaccination, no significant differences were found between vaccination within the first year of life and afterwards. Vaccinated animals showed seventeen times more reactions than the non-vaccinated in the BSIT, but only four times more in the CIT. In conclusion, comparative intradermal test can be a useful tool to differentiate paratuberculosis vaccine cross-reactions from specific bovine tuberculosis reactions according to the European and Spanish legislation.  相似文献   
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wings apart (wap) is a recessive, semilethal gene located on the X chromosome in Drosophila melanogaster, which is required for normal wing-vein patterning. We show that the wap mutation also results in loss of the adult jump muscle. We use complementation mapping and gene-specific RNA interference to localize the wap locus to the proximal X chromosome. We identify the annotated gene CG14614 as the gene affected by the wap mutation, since one wap allele contains a non-sense mutation in CG14614, and a genomic fragment containing only CG14614 rescues the jump-muscle phenotypes of two wap mutant alleles. The wap gene lies centromere-proximal to touch-insensitive larva B and centromere-distal to CG14619, which is tentatively assigned as the gene affected in introverted mutants. In mutant wap animals, founder cell precursors for the jump muscle are specified early in development, but are later lost. Through tissue-specific knockdowns, we demonstrate that wap function is required in both the musculature and the nervous system for normal jump-muscle formation. wap/CG14614 is homologous to vertebrate wdr68, DDB1 and CUL4 associated factor 7, which also are expressed in neuromuscular tissues. Thus, our findings provide insight into mechanisms of neuromuscular development in higher animals and facilitate the understanding of neuromuscular diseases that may result from mis-expression of muscle-specific or neuron-specific genes.  相似文献   
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