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151.
Irene Cardinali Hovirag Lancioni Andrea Giontella Marco Rosario Capodiferro Stefano Capomaccio Luca Buttazzoni Giovanni Paolo Biggio Raffaele Cherchi Emidio Albertini Anna Olivieri Katia Cappelli Alessandro Achilli Maurizio Silvestrelli 《PloS one》2016,11(4)
BackgroundThe climatic and cultural diversity of the Italian Peninsula triggered, over time, the development of a great variety of horse breeds, whose origin and history are still unclear. To clarify this issue, analyses on phenotypic traits and genealogical data were recently coupled with molecular screening.MethodologyTo provide a comprehensive overview of the horse genetic variability in Italy, we produced and phylogenetically analyzed 407 mitochondrial DNA (mtDNA) control-region sequences from ten of the most important Italian riding horse and pony breeds: Bardigiano, Esperia, Giara, Lipizzan, Maremmano, Monterufolino, Murgese, Sarcidano, Sardinian Anglo-Arab, and Tolfetano. A collection of 36 Arabian horses was also evaluated to assess the genetic consequences of their common use for the improvement of some local breeds.ConclusionsIn Italian horses, all previously described domestic mtDNA haplogroups were detected as well as a high haplotype diversity. These findings indicate that the ancestral local mares harbored an extensive genetic diversity. Moreover, the limited haplotype sharing (11%) with the Arabian horse reveals that its impact on the autochthonous mitochondrial gene pools during the final establishment of pure breeds was marginal, if any. The only significant signs of genetic structure and differentiation were detected in the geographically most isolated contexts (i.e. Monterufolino and Sardinian breeds). Such a geographic effect was also confirmed in a wider breed setting, where the Italian pool stands in an intermediate position together with most of the other Mediterranean stocks. However, some notable exceptions and peculiar genetic proximities lend genetic support to historical theories about the origin of specific Italian breeds. 相似文献
152.
Biotransformations of Bile Acids with Bacteria from Cayambe Slaughterhouse (Ecuador): Synthesis of Bendigoles
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Stefania Costa Maria Elena Maldonado Rodriguez Irene Rugiero Morena De Bastiani Alessandro Medici Elena Tamburini Paola Pedrini 《化学与生物多样性》2016,13(8):969-975
The biotransformations of cholic acid ( 1a ), deoxycholic acid ( 1b ), and hyodeoxycholic acid ( 1c ) to bendigoles and other metabolites with bacteria isolated from the rural slaughterhouse of Cayambe (Pichincha Province, Ecuador) were reported. The more active strains were characterized, and belong to the genera Pseudomonas and Rhodococcus. Various biotransformation products were obtained depending on bacteria and substrates. Cholic acid ( 1a ) afforded the 3‐oxo and 3‐oxo‐4‐ene derivatives 2a and 3a (45% and 45%, resp.) with P. mendocina ECS10, 3,12‐dioxo‐4‐ene derivative 4a (60%) with Rh. erythropolis ECS25, and 9,10‐secosteroid 6 (15%) with Rh. erythropolis ECS12. Bendigole F ( 5a ) was obtained in 20% with P. fragi ECS22. Deoxycholic acid ( 1b ) gave 3‐oxo derivative 2b with P. prosekii ECS1 and Rh. erythropolis ECS25 (20% and 61%, resp.), while 3‐oxo‐4‐ene derivative 3b was obtained with P. prosekii ECS1 and P. mendocina ECS10 (22% and 95%, resp.). Moreover, P. fragi ECS9 afforded bendigole A ( 8b ; 80%). Finally, P. mendocina ECS10 biotransformed hyodeoxycholic acid ( 1c ) to 3‐oxo derivative 2c (50%) and Rh. erythropolis ECS12 to 6α‐hydroxy‐3‐oxo‐23,24‐dinor‐5β‐cholan‐22‐oic acid ( 9c , 66%). Bendigole G ( 5c ; 13%) with P. prosekii ECS1 and bendigole H ( 8c ) with P. prosekii ECS1 and Rh. erythropolis ECS12 (20% and 16%, resp.) were obtained. 相似文献
153.
Trey K. Sato Mary Tremaine Lucas S. Parreiras Alexander S. Hebert Kevin S. Myers Alan J. Higbee Maria Sardi Sean J. McIlwain Irene M. Ong Rebecca J. Breuer Ragothaman Avanasi Narasimhan Mick A. McGee Quinn Dickinson Alex La Reau Dan Xie Mingyuan Tian Jeff S. Piotrowski Jennifer L. Reed Yaoping Zhang Joshua J. Coon Chris Todd Hittinger Audrey P. Gasch Robert Landick 《PLoS genetics》2016,12(11)
154.
155.
Brigitta Ine Van Tussenbroek Tania Valdivia‐Carrillo Irene Teresa Rodríguez‐Virgen Sylvia Nashieli Marisela Sanabria‐Alcaraz Karina Jiménez‐Durán Kor Jent Van Dijk Guadalupe Judith Marquez‐Guzmán 《Ecology and evolution》2016,6(15):5542-5556
The high prevalence of dioecy in marine angiosperms or seagrasses (>50% of all species) is thought to enforce cross‐fertilization. However, seagrasses are clonal plants, and they may still be subject to sibling‐mating or bi‐parental inbreeding if the genetic neighborhood is smaller than the size of the genets. We tested this by determining the genetic neighborhoods of the dioecious seagrass Thalassia testudinum at two sites (Back‐Reef and Mid‐Lagoon) in Puerto Morelos Reef Lagoon, Mexico, by measuring dispersal of pollen and seeds in situ, and by fine‐scale spatial autocorrelation analysis with eight polymorphic microsatellite DNA markers. Prevalence of inbreeding was verified by estimating pairwise kinship coefficients; and by analysing the genotypes of seedlings grown from seeds in mesocosms. Average dispersal of pollen was 0.3–1.6 m (max. 4.8 m) and of seeds was 0.3–0.4 m (max. 1.8 m), resulting in a neighborhood area of 7.4 m2 (range 3.4–11.4 m2) at Back‐Reef and 1.9 (range 1.87–1.92 m2) at Mid‐Lagoon. Neighborhood area (Na) derived from spatial autocorrelation was 0.1–20.5 m2 at Back‐Reef and 0.1–16.9 m2 at Mid‐Lagoon. Maximal extensions of the genets, in 19 × 30 m plots, were 19.2 m (median 7.5 m) and 10.8 m (median 4.8 m) at Back‐Reef and Mid‐Lagoon. There was no indication of deficit or excess of heterozygotes nor were coefficients of inbreeding (FIS) significant. The seedlings did not show statistically significant deficit of heterozygotes (except for 1 locus at Back‐Reef). Contrary to our expectations, we did not find evidence of bi‐parental inbreeding in this dioecious seagrass with large genets but small genetic neighborhoods. Proposed mechanisms to avoid bi‐parental inbreeding are possible selection against homozygotes during fecundation or ovule development. Additionally, the genets grew highly dispersed (aggregation index Ac was 0.09 and 0.10 for Back‐Reef and Mid‐Lagoon, respectively); such highly dispersed guerrilla‐like clonal growth form likely increases the probability of crossing between different potentially unrelated genets. 相似文献
156.
The pH in bacterial biofilms on teeth is of central importance for dental caries, a disease with a high worldwide prevalence. Nutrients and metabolites are not distributed evenly in dental biofilms. A complex interplay of sorption to and reaction with organic matter in the biofilm reduces the diffusion paths of solutes and creates steep gradients of reactive molecules, including organic acids, across the biofilm. Quantitative fluorescent microscopic methods, such as fluorescence life time imaging or pH ratiometry, can be employed to visualize pH in different microenvironments of dental biofilms. pH ratiometry exploits a pH-dependent shift in the fluorescent emission of pH-sensitive dyes. Calculation of the emission ratio at two different wavelengths allows determining local pH in microscopic images, irrespective of the concentration of the dye. Contrary to microelectrodes the technique allows monitoring both vertical and horizontal pH gradients in real-time without mechanically disturbing the biofilm. However, care must be taken to differentiate accurately between extra- and intracellular compartments of the biofilm. Here, the ratiometric dye, seminaphthorhodafluor-4F 5-(and-6) carboxylic acid (C-SNARF-4) is employed to monitor extracellular pH in in vivo grown dental biofilms of unknown species composition. Upon exposure to glucose the dye is up-concentrated inside all bacterial cells in the biofilms; it is thus used both as a universal bacterial stain and as a marker of extracellular pH. After confocal microscopic image acquisition, the bacterial biomass is removed from all pictures using digital image analysis software, which permits to exclusively calculate extracellular pH. pH ratiometry with the ratiometric dye is well-suited to study extracellular pH in thin biofilms of up to 75 µm thickness, but is limited to the pH range between 4.5 and 7.0. 相似文献
157.
Yilong Fu Lai-Chun Ong Sudhir H. Ranganath Lin Zheng Irene Kee Wenbo Zhan Sidney Yu Pierce K. H. Chow Chi-Hwa Wang 《PloS one》2016,11(2)
Early diagnosis of low grade glioma has been a challenge to clinicians. Positron Emission Tomography (PET) using 18F-FDG as a radio-tracer has limited utility in this area because of the high background in normal brain tissue. Other radiotracers such as 18F-Fluorocholine (18F-FCH) could provide better contrast between tumor and normal brain tissue but with high incidence of false positives. In this study, the potential application of a dual tracer 18F-FCH/18F-FDG-PET is investigated in order to improve the sensitivity of PET imaging for low grade glioma diagnosis based on a mouse orthotopic xenograft model. BALB/c nude mice with and without orthotopic glioma xenografts from U87 MG-luc2 glioma cell line are used for the study. The animals are subjected to 18F-FCH and 18F-FDG PET imaging, and images acquired from two separate scans are superimposed for analysis. The 18F-FCH counts are subtracted from the merged images to identify the tumor. Micro-CT, bioluminescence imaging (BLI), histology and measurement of the tumor diameter are also conducted for comparison. Results show that there is a significant contrast in 18F-FCH uptake between tumor and normal brain tissue (2.65 ± 0.98), but with a high false positive rate of 28.6%. The difficulty of identifying the tumor by 18F-FDG only is also proved in this study. All the tumors can be detected based on the dual tracer technique of 18F-FCH/ 18F-FDG-PET imaging in this study, while the false-positive caused by 18F-FCH can be eliminated. Dual tracer 18F-FCH/18F-FDG PET imaging has the potential to improve the visualization of low grade glioma. 18F-FCH delineates tumor areas and the tumor can be identified by subtracting the 18F-FCH counts. The sensitivity was over 95%. Further studies are required to evaluate the possibility of applying this technique in clinical trials. 相似文献
158.
Tamara Fernández-Marcelo Andrés Sánchez-Pernaute Irene Pascua Carmen De Juan Jacqueline Head Antonio-José Torres-García Pilar Iniesta 《PloS one》2016,11(2)
The role of telomeres and telomerase in colorectal cancer (CRC) is well established as the major driving force in generating chromosomal instability. However, their potential as prognostic markers remains unclear. We investigated the outcome implications of telomeres and telomerase in this tumour type. We considered telomere length (TL), ratio of telomere length in cancer to non-cancer tissue (T/N ratio), telomerase activity and TERT levels; their relation with clinical variables and their role as prognostic markers. We analyzed 132 CRCs and paired non-cancer tissues. Kaplan-Meier curves for disease-free survival were calculated for TL, T/N ratio, telomerase activity and TERT levels. Overall, tumours had shorter telomeres than non-tumour tissues (P < 0.001) and more than 80% of CRCs displayed telomerase activity. Telomere lengths of non-tumour tissues and CRCs were positively correlated (P < 0.001). Considering telomere status and clinical variables, the lowest degree of telomere shortening was shown by tumours located in the rectum (P = 0.021). Regarding prognosis studies, patients with tumours showing a mean TL < 6.35 Kb experienced a significantly better clinical evolution (P < 0.001) and none of them with the highest degree of tumour telomere shortening relapsed during the follow-up period (P = 0.043). The mean TL in CRCs emerged as an independent prognostic factor in the Cox analysis (P = 0.017). Telomerase-positive activity was identified as a marker that confers a trend toward a poor prognosis. In CRC, our results support the use of telomere status as an independent prognostic factor. Telomere status may contribute to explaining the different molecular identities of this tumour type. 相似文献
159.
Catherine M. Hall Nigel A. Adams J. Stuart Bradley Kate A. Bryant Alisa A. Davis Christopher R. Dickman Tsumugi Fujita Shinichi Kobayashi Christopher A. Lepczyk E. Anne McBride Kenneth H. Pollock Irene M. Styles Yolanda van Heezik Ferian Wang Michael C. Calver 《PloS one》2016,11(4)
International differences in practices and attitudes regarding pet cats'' interactions with wildlife were assessed by surveying citizens from at least two cities in Australia, New Zealand, the UK, the USA, China and Japan. Predictions tested were: (i) cat owners would agree less than non-cat owners that cats might threaten wildlife, (ii) cat owners value wildlife less than non-cat owners, (iii) cat owners are less accepting of cat legislation/restrictions than non-owners, and (iv) respondents from regions with high endemic biodiversity (Australia, New Zealand, China and the USA state of Hawaii) would be most concerned about pet cats threatening wildlife. Everywhere non-owners were more likely than owners to agree that pet cats killing wildlife were a problem in cities, towns and rural areas. Agreement amongst non-owners was highest in Australia (95%) and New Zealand (78%) and lowest in the UK (38%). Irrespective of ownership, over 85% of respondents from all countries except China (65%) valued wildlife in cities, towns and rural areas. Non-owners advocated cat legislation more strongly than owners except in Japan. Australian non-owners were the most supportive (88%), followed by Chinese non-owners (80%) and Japanese owners (79.5%). The UK was least supportive (non-owners 43%, owners 25%). Many Australian (62%), New Zealand (51%) and Chinese owners (42%) agreed that pet cats killing wildlife in cities, towns and rural areas was a problem, while Hawaiian owners were similar to the mainland USA (20%). Thus high endemic biodiversity might contribute to attitudes in some, but not all, countries. Husbandry practices varied internationally, with predation highest where fewer cats were confined. Although the risk of wildlife population declines caused by pet cats justifies precautionary action, campaigns based on wildlife protection are unlikely to succeed outside Australia or New Zealand. Restrictions on roaming protect wildlife and benefit cat welfare, so welfare is a better rationale. 相似文献
160.