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31.
Price DC Chan CX Yoon HS Yang EC Qiu H Weber AP Schwacke R Gross J Blouin NA Lane C Reyes-Prieto A Durnford DG Neilson JA Lang BF Burger G Steiner JM Löffelhardt W Meuser JE Posewitz MC Ball S Arias MC Henrissat B Coutinho PM Rensing SA Symeonidi A Doddapaneni H Green BR Rajah VD Boore J Bhattacharya D 《Science (New York, N.Y.)》2012,335(6070):843-847
32.
Rosa María Arias Gabriela Heredia-Abarca Vinicio J. Sosa Luis Ernesto Fuentes-Ramírez 《Agroforestry Systems》2012,85(1):179-193
We evaluate the arbuscular mycorrhizal fungi (AMF) community as measured by spores in different coffee production systems (at the depth of 0?C15?cm). In addition, we analyze the similarities between the AMF communities in coffee production systems and those that occur in a tropical montane cloud forest patch in order to evaluate the capacity of coffee production systems to preserve the native AMF community. We carried out four samplings in five coffee production systems representative of a vegetation structure gradient, and in a forest. From 120 soil samples, 33 morphospecies were detected. In all the sites, the dominant morphospecies were Glomus clarum and Glomus sp. 3. We found no significant difference in AMF spore richness between sites. Diversity was similar in most of the coffee production systems. Significant differences were only detected in spore abundance; during the dry season the forest, shaded traditional rustic system and shaded simple system presented the highest spore abundance. With the exception of one species exclusive to the forest, the coffee production systems all share the same AMF species as the forest. The coffee production systems with the greatest similarity to cloud forest were the shaded traditional rustic system and the shaded simple system. It is suggested that control of weeds and fertilization could be important factors influencing the composition and abundance of AMF spores in coffee production systems. 相似文献
33.
Arias M Yeargan M Francisco I Dangoudoubiyam S Becerra P Francisco R Sánchez-Andrade R Paz-Silva A Howe DK 《Veterinary parasitology》2012,185(2-4):301-304
Horses serve as an intermediate host for several species of Sarcocystis, all of which utilize canids as the definitive host. Sarcocystis spp. infection and formation of latent sarcocysts in horses often appears to be subclinical, but morbidity can occur, especially when the parasite burden is large. A serological survey was conducted to determine the presence of antibodies against Sarcocystis spp. in seemingly healthy horses from the Galicia region of Spain. Western blot analyses using Sarcocystis neurona merozoites as heterologous antigen suggested greater than 80% seroprevalance of Sarcocystis spp. in a sample set of 138 horses. The serum samples were further tested with enzyme-linked immunosorbent assays (ELISAs) based on recombinant S. neurona-specific surface antigens (rSnSAGs). As expected for horses from the Eastern Hemisphere, less than 4% of the serum samples were positive when analyzed with either the rSnSAG2 or the rSnSAG4/3 ELISAs. An additional 246 horses were tested using the rSnSAG2 ELISA, which revealed that less than 3% of the 384 samples were seropositive. Collectively, the results of this serologic study suggested that a large proportion of horses from this region of Spain are exposed to Sarcocystis spp. Furthermore, the anti-Sarcocystis seroreactivity in these European horses could be clearly distinguished from anti-S. neurona antibodies using the rSnSAG2 and rSnSAG4/3 ELISAs. 相似文献
34.
D. Arias J. Peñaloza-Ramírez O. Dorado P. Cuevas-Reyes Esaú Leyva Ana Luisa Albarrán-Lara G. Rangel-Altamirano 《Genetic Resources and Crop Evolution》2010,57(8):1227-1238
Jacaratia mexicana A. DC. (Caricaceae) is a tropical tree distributed throughout Mexico and Mesoamerica. Some evidence in Mexico indicates the
presence of an incipient domestication process in this species. Phylogeographical analyses can potentially determine contemporary
patterns of gene flow, isolation between population lineages, as well as historical processes such as population bottlenecks
or expansions on their geographical areas. In this study we reconstruct the phylogeographical patterns in populations of J. mexicana A. DC., in order to find differences between genetic variation among wild and cultivated populations utilizing chloroplast
DNA and nuclear DNA sequences. We generate a Bayesian phylogenetic tree, to estimate the divergence time between clades using
calibrated mutation rates. We also infer the demographic history of these populations using neutrality tests among wild and
cultivated accessions. We identified higher levels of haplotype and nucleotide diversity for the cpDNA and ITS types in wild
populations than in domesticated populations. These results indicate a reduction of genetic diversity derived from human selection
on domestication traits. Neutrality test suggests population expansion detected by the significant negative values of Fu’s
Fs in the cultivated populations of this specie. These process results in an excess of rare polymorphism with the fixation
of certain advantageous mutation throughout time, this implication are in accordance with the role of the strong selection
in the fruit traits of J. mexicana. The dated phylogeny constructed with BEAST program indicated a dispersion pattern for the J. mexicana ancestors across the South Pacific and South Eastern populations during the late Pliocene. Posterior dispersion and divergence
in the clades from Central Mexico and North Pacific are in agreement with the episodes of mountain-building in different regions
of Mexico. 相似文献
35.
Agüero M Arias M Romero LJ Zamora MJ Sánchez-Vizcaíno JM 《Veterinary microbiology》2002,86(4):337-341
At the end of September 2000, clinical symptoms of Bluetongue appeared in sheep flocks of the Balearic Islands (Spain). The presence of the BTV serotype 2 in tissue and blood samples of affected animals was confirmed by laboratory techniques. A systematic vaccination were carried out in affected areas using a live monovalent serotype 2 vaccine available from Onderstepoort laboratory (South Africa). In order to perform epidemiological studies, a new method to differentiate between the NS1 genes of BTV-2 affecting the Balearic islands and that of the Onderstepoort commercial live virus vaccine (monovalent, serotype 2) has been developed. This procedure is based on the use of an RT-PCR, followed by restriction endonuclease analysis. Epidemiological data of a study carried out in the period January-October 2001 using this procedure are included. 相似文献
36.
WE Scherrer AE Kyles VF Samii EM Hardie PH Kass CR Gregory 《New Zealand veterinary journal》2013,61(6):330-333
AIMS: To assess the sensitivity of non-angiographic contrast-enhanced computed tomography (CT) to determine the presence of vascular invasion of cranial mediastinal masses in dogs and a cat, and to evaluate the association between vascular invasion and peri-operative mortality. METHODS: A retrospective study was conducted on 25 dogs and one cat. CT scans were completed with slices ranging from 2 to 10 mm. CT images were evaluated by a board-certifi ed radiologist blinded to previous diagnoses and surgical fi ndings. Each CT study was evaluated for vascular invasion, defi ned as disruption of the vessel wall and extension of the mass into the vessel lumen. Data retrieved from the surgery reports included surgical approach, whether vascular invasion was present, the surgeon's decision on operability, and post-operative complications. RESULTS: Computed tomographic evaluation revealed 25/26 masses had no evidence of vascular invasion. During surgical exploration, 10/26 masses were found to invade major regional vasculature; the cranial vena cava (CVC) was the vessel most commonly invaded (7/10 animals), and 4/7 (57%) patients with invasion of the CVC were euthanised or died in the perioperative period, from surgical or disease-related problems, which was signifi cantly higher than patients without vascular invasion (p=0.045). CONCLUSIONS: Non-angiographic contrast-enhanced CT was signifi cantly less sensitive for detecting vascular invasion of cranial mediastinal masses when compared with surgical evaluation. If the CVC was invaded by a tumour there was a signifi cant risk of death peri-operatively when compared with non-invasive cases. CLINICAL RELEVANCE: Due to the signifi cantly higher mortality risk associated with invasion of the CVC, a more sensitive method than CT should be investigated to determine vascular invasion of mediastinal masses pre-operatively. 相似文献
37.
BV Sanches JHF Pontes AC Basso CR Ferreira F Perecin MM Seneda 《Reproduction in domestic animals》2013,48(1):e7-e9
In this work, we evaluated whether embryo development and pregnancy rates would be affected by culturing bovine Bos indicus embryos in Synthetic Oviductal Fluid with amino acids (SOFaa) or G1/G2 sequential medium under a low‐oxygen atmosphere. Using Ovum Pick Up, we obtained 1,538 oocytes, divided into G1/G2 (n = 783) and SOFaa (n = 755). No difference was observed for blastocyst development among the groups (27.8% ± 14.6 and 34.9% ± 20.0 for G1/G2 and SOFaa respectively, p > 0.05). Transferring the embryos (n = 450) from both groups to recipients resulted in similar pregnancy rates for the G1/G2 (38.4% n = 78/203) compared to the SOFaa (39.7% n = 98/247). Our findings confirm that Bos indicus embryos cultured in SOFaa and G1/G2 under low‐oxygen atmosphere have similar in vitro (blastocyst rate) and in vivo (pregnancy rate) developmental capacity. However, embryos cultured in G1/G2 medium have higher cleavage than those cultured in SOFaa medium. 相似文献
38.
Jervis M. Huaman O. Cahuascanco B. Bahamonde J. Cortez J. Arias J. I. Torres C. G. Peralta O. A. 《Veterinary research communications》2019,43(3):165-178
Veterinary Research Communications - Mesenchymal stem cells (MSCs) are found in virtually all tissues, where they self-renew and differentiate into multiple cell types. Cumulative data indicate... 相似文献
39.
Effect of short‐term exposure of cumulus–oocyte complex to 3‐morpholinosydnonimine on in vitro embryo development and gene expression in cattle 下载免费PDF全文
P Loren C Cheuquemán E Sánchez J Risopatrón ME Arias R Felmer R Sánchez 《Reproduction in domestic animals》2016,51(6):1010-1019
Short‐term exposure of gametes to different types of stress might induce stress tolerance in mammalian embryos. The aim of this study was to evaluate the effect of short‐term exposure of bovine mature cumulus–oocyte complex (COC) to 3‐morpholinosydnonimine (SIN‐1) on subsequent in vitro embryo development, embryo quality and relative gene expression. Matured COCs were incubated with SIN‐1 (0, 0.1, 1, 10 and 100 μM SIN‐1) for 1 hr before in vitro fertilization and zygotes were cultured until Day 7. The cleavage rate at 72 hr did not show any differences among groups. However, the blastocyst rate on Day 7 decreased with all treatments evaluated, with the embryos generated with 10 μM SIN‐1 showing the lowest embryo production rate. Embryo quality analysis did not show any differences in total cell number (TCN) or inner cell mass (ICM) among groups. Relative gene expression analysis showed a downregulation of eNOS expression and an upregulation of nNOS expression in all treatments evaluated compared to the control group. Also, a downregulation was observed in some treatments: SOD2 at 0.1 μM; SOD1 at 0.1 and 100 μM; PRDX5 at 0.1, 10 and 100 μM; and NANOG at 10 and 100 μM; and an upregulation of CDX2 expression was observed at 100 μM. The other genes (OCT4, HIF1A, HSPA1A, BCL2A and iNOS) did not show any differences in the relative gene expression. These results suggest that the short‐term exposure of mature bovine COCs to SIN‐1 does not induce stress tolerance and has no beneficial effect on bovine in vitro embryo production. 相似文献
40.
Arias M Morrondo P Hillyer GV Sánchez-Andrade R Suárez JL Lomba C Pedreira J Díaz P Díez-Baños P Paz-Silva A 《Veterinary parasitology》2007,146(1-2):46-49
A 2.9 kDa recombinant-Fasciola hepatica protein (FhrAPS) was employed to estimate the prevalence of fasciolosis in sheep maintained under field conditions. For this purpose, 340 samples with known status in relation to fasciolosis by using a direct-ELISA and the coprological sedimentation were used. These samples were analysed by using an indirect-ELISA (iELISA) and the FhrAPS recombinant protein and excretory/secretory antigens (FhES) of this trematode. Current fasciolosis (CF) was named when results were positive to antigenemia and/or coprology. Out of 198 sheep with current fasciolosis, 68% were positive to the FhrAPS-ELISA test and 53% to the FhES. We observed 14% of the CF-neg sheep were positive to the FhrAPS, whereas this percentage was 52% with the FhES. A significant correlation between FhrAPS and current fasciolosis was obtained (r2=0.513, p=0.001). We concluded that the FhrAPS provides a more suitable antigen than FhES for developing field trials to know the prevalence of early and current fasciolosis. 相似文献