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51.
T. WORTHINGTON P. S. KEMP P. E. OSBORNE A. DILLEN J. COECK M. BUNZEL‐DRÜKE M. NAURA J. GREGORY K. EASTON 《Freshwater Biology》2012,57(3):602-611
1. Availability of suitable habitat is a prerequisite for species reintroduction success, and to ensure population persistence, investigations of a species’ habitat utilisation throughout its life history should be conducted as part of a feasibility study. 2. Habitat utilisation models for burbot, Lota lota, developed using data from field studies conducted in France and Germany and information from the literature were used to assess the feasibility of reintroducing burbot into rivers of its former native range in eastern England. 3. Per cent tree roots, aquatic vegetation and flow types were important predictors of adult burbot abundance. Furthermore, the habitat utilisation models were supplemented with information from the literature, which suggested that off‐channel habitat such as wetlands and backwaters is important for spawning and nursery stages. 4. An assessment of the habitat availability in the rivers of the burbot’s former native range using variables related to spawning and nursery and adult life stages showed that although adult habitat was widely distributed, the availability of spawning and nursery habitat was less abundant, potentially limiting successful reestablishment. 5. Potential suitable habitat was concentrated in the central and southern areas of the species’ former English distribution. Overall, rivers of the burbot’s former range potentially afford suitable habitat to sustain a reintroduced population. However, sites should be preferentially selected on the basis of having appropriate spawning and nursery areas. 相似文献
52.
Harries LW Pilling LC Hernandez LD Bradley-Smith R Henley W Singleton AB Guralnik JM Bandinelli S Ferrucci L Melzer D 《Aging cell》2012,11(2):262-268
Declining muscle strength is a core feature of aging. Several mechanisms have been postulated, including CCAAT/enhancer-binding protein-beta (C/EBP-β)-triggered macrophage-mediated muscle fiber regeneration after micro-injury, evidenced in a mouse model. We aimed to identify in vivo circulating leukocyte gene expression changes associated with muscle strength in the human adult population. We undertook a genome-wide expression microarray screen, using peripheral blood RNA samples from InCHIANTI study participants (aged 30 and 104). Logged expression intensities were regressed with muscle strength using models adjusted for multiple confounders. Key results were validated by real-time PCR. The Short Physical Performance Battery (SPPB) score tested walk speed, chair stand, and balance. CEBPB expression levels were associated with muscle strength (β coefficient = 0.20560, P = 1.03*10(-6), false discovery rate q = 0.014). The estimated handgrip strength in 70-year-old men in the lowest CEBPB expression tertile was 35.2 kg compared with 41.2 kg in the top tertile. CEBPB expression was also associated with hip, knee, ankle, and shoulder strength and the SPPB score (P = 0.018). Near-study-wide associations were also noted for TGF-β3 (P = 3.4*10(-5) , q = 0.12) and CEBPD expression (P = 9.7*10(-5) , q = 0.18) but not for CEBPA expression. We report here a novel finding that raised CEBPB expression in circulating leukocyte-derived RNA samples in vivo is associated with greater muscle strength and better physical performance in humans. This association may be consistent with mouse model evidence of CEBPB-triggered muscle repair: if this mechanism is confirmed, it may provide a target for intervention to protect and enhance aging muscle. 相似文献
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56.
Qayyum R Snively BM Ziv E Nalls MA Liu Y Tang W Yanek LR Lange L Evans MK Ganesh S Austin MA Lettre G Becker DM Zonderman AB Singleton AB Harris TB Mohler ER Logsdon BA Kooperberg C Folsom AR Wilson JG Becker LC Reiner AP 《PLoS genetics》2012,8(3):e1002491
Several genetic variants associated with platelet count and mean platelet volume (MPV) were recently reported in people of European ancestry. In this meta-analysis of 7 genome-wide association studies (GWAS) enrolling African Americans, our aim was to identify novel genetic variants associated with platelet count and MPV. For all cohorts, GWAS analysis was performed using additive models after adjusting for age, sex, and population stratification. For both platelet phenotypes, meta-analyses were conducted using inverse-variance weighted fixed-effect models. Platelet aggregation assays in whole blood were performed in the participants of the GeneSTAR cohort. Genetic variants in ten independent regions were associated with platelet count (N?=?16,388) with p<5×10(-8) of which 5 have not been associated with platelet count in previous GWAS. The novel genetic variants associated with platelet count were in the following regions (the most significant SNP, closest gene, and p-value): 6p22 (rs12526480, LRRC16A, p?=?9.1×10(-9)), 7q11 (rs13236689, CD36, p?=?2.8×10(-9)), 10q21 (rs7896518, JMJD1C, p?=?2.3×10(-12)), 11q13 (rs477895, BAD, p?=?4.9×10(-8)), and 20q13 (rs151361, SLMO2, p?=?9.4×10(-9)). Three of these loci (10q21, 11q13, and 20q13) were replicated in European Americans (N?=?14,909) and one (11q13) in Hispanic Americans (N?=?3,462). For MPV (N?=?4,531), genetic variants in 3 regions were significant at p<5×10(-8), two of which were also associated with platelet count. Previously reported regions that were also significant in this study were 6p21, 6q23, 7q22, 12q24, and 19p13 for platelet count and 7q22, 17q11, and 19p13 for MPV. The most significant SNP in 1 region was also associated with ADP-induced maximal platelet aggregation in whole blood (12q24). Thus through a meta-analysis of GWAS enrolling African Americans, we have identified 5 novel regions associated with platelet count of which 3 were replicated in other ethnic groups. In addition, we also found one region associated with platelet aggregation that may play a potential role in atherothrombosis. 相似文献
57.
An update on North American boar stud practices 总被引:1,自引:0,他引:1
This survey included 44 boar studs from Canada and the USA with a total of approximately 10,000 boars. Studs with 51-500 boars accounted for 84% of respondents. More than 90% of boars were housed in stalls. Evaporative and mechanical cooling systems predominated and boars were typically fed based on body condition. The predominant age of boars was 1-2 years with annual culling rates between 20 and 70%. The primary reasons for culling included genetic improvement, semen quality and feet and leg issues. Collection occurred commonly on Mondays and Thursdays and boars were rested 3-7 days between collections. The average sperm produced per boar per week was 51-150 billions and resulted in 21-40 doses per boar per week. Most studs collected boars using double gloves and disposable cups or liners and used pre-warmed containers. Ejaculate pooling was practiced by >60% of studs. Evaluation of semen for motility was performed with 0-5min of warming in extender with viewing at 100-400x magnification. Concentration estimation occurred by photometer and CASA for 88% of studs. Ejaculate discard occurred for reasons of poor motility, abnormal sperm and bacteria. Most studs retained extended samples for 3-7 days for quality control. Discard rates were most common between 1 and 10% and were related to individual boar and season. Doses of semen contained 2-4 billion sperms, with final sperm numbers adjusted for fertile sperm and packaged as doses in tubes and bags with 60-100mL. 相似文献
58.
Margaret A. Kihlken Chloe Singleton Nick E. Le Brun 《Journal of biological inorganic chemistry》2008,13(6):1011-1023
The chaperone CopZ together with the P-type ATPase transporter CopA constitute a copper-detoxification system in Bacillus subtilis that is commonly found in bacteria and higher cells. Previous studies of the regulation of the copZA operon showed that expression is significantly upregulated in response to elevated concentrations of environmental silver and cadmium, as well as copper. Here, we have used spectroscopic and bioanalytical methods to investigate in detail the capacity of CopZ to bind these metal ions (as Ag(+) and Cd(2+)). We demonstrate that Ag(+) binding mimics closely that of Cu(+): Ag(+)-mediated dimerisation of the protein occurs, and distinct Ag(+)-bound species are formed at higher Ag(+) loadings. Cd(2+) also binds to CopZ, but exhibits significantly different behaviour. Cd(2+)-mediated dimerisation is only observed at low loadings, such that at 0.5 and one Cd(2+) per CopZ the protein is present mainly in a monomeric form; and multinuclear higher-order forms of Cd(2+)-CopZ are not observed. Competition binding studies reveal that Ag(+) binds with an affinity very similar to that of Cu(+), while Cd(2+) binding is significantly weaker. These data provide support for the proposal that CopZ may be involved in the detoxification of silver and cadmium, in addition to copper. 相似文献
59.
F L Singleton R W Attwell M S Jangi R R Colwell 《Applied and environmental microbiology》1982,43(5):1080-1085
Laboratory microcosms were employed to evaluate the influence of selected environmental parameters, organic nutrient concentration, and salinity on the growth and survival of a toxigenic strain of Vibrio cholerae LA4808. Over the range conditions tested, this strain of V. cholerae showed maximum response as determined by increased plate counts and direct microscopic counts in microcosms prepared with a chemically defined sea salts solution at a salinity of 25%, but with lower or higher salinity levels, the maximum population size declined. When added organic concentrations of less than 1,000 micrograms/liter were present, a marked salinity effect on the growth of V. cholerae was detected. However, at or above an organic nutrient concentration of 1,000 micrograms/liter, the need for an optimum salinity level was spared. From the results of this study, it is concluded that V. cholerae can grow under conditions of organic nutrient concentration and salinity typical of estuaries. Results obtained support the hypothesis that V. cholerae is an autochthonous member of the estuarine microbial community. 相似文献
60.
The MIND multiprotein complex is a conserved, essential component of eukaryotic kinetochores and is a constituent of the tripartite KMN network that directly attaches the kinetochore to the mitotic spindle. The primary microtubule-binding complex in this network, NDC80, has been extensively characterized, but very little is known about the structure or function of the MIND complex. In this study, we present biochemical, hydrodynamic, electron microscopy, and small-angle x-ray scattering data that provide insight into the overall architecture and assembly of the MIND complex and the physical relationship of the complex with other components of the KMN network. We propose a model for the overall structure of the complex and provide data on the interactions with NDC80, Spc105p, and thus the mitotic spindle. 相似文献