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111.
Paradiopatra multibranchiata, an onuphid found commonly in shelf sediments of the tropical eastern Pacific, is described here. It belongs to the group of Paradiopatra species characterized by the presence of branchiae on the most anterior parapodia (chaetigers 2–3), with at least seven filaments when fully developed. The new species closely resembles P. parva, also distributed in the eastern Pacific but in temperate habitats. It can be distinguished from the latter by the presence rather than the absence of eyes, and because it bears the highest number of branchial filaments (up to 37) observed in any Paradiopatra species known so far (14–18 filaments at most). The taxonomic status of the new species is supported by comparative morphometric and multivariate analyses, which also allowed us to verify its differences with P. parva. The branchial development was the most useful character to determine the relationships between the specimens of P. multibranchiata sp. nov., while its separation from P. parva (Wilks’ lambda?=?0.060, P?<?0.0001) was weighted most heavily by the number of filaments at chaetigers 2 and 10, and the length of the median antenna. An anatomical examination with methylene blue stain and with scanning electron microscopy was carried out to illustrate the ventral glandular pad staining pattern and the features of their cuticular pores.
http://zoobank.org/urn:lsid:zoobank.org:pub:194636C6-A032-4B1F-B0B8-1D494C344623 相似文献
112.
Association and interaction of the IL4R,IL4, and IL13 loci with type 1 diabetes among Filipinos 下载免费PDF全文
Bugawan TL Mirel DB Valdes AM Panelo A Pozzilli P Erlich HA 《American journal of human genetics》2003,72(6):1505-1514
In the search for genes involved in type 1 diabetes (T1D), other than the well-established risk alleles at the human leukocyte antigen loci, we have investigated the association and interaction of polymorphisms in genes involved in the IL4/IL13 pathway in a sample of 90 Filipino patients with T1D and 94 controls. Ten single-nucleotide polymorphisms (SNPs), including two promoter SNPs in the IL4R locus on chromosome 16p11, one promoter SNP in the IL4 locus on chromosome 5q31, and four SNPs--including two promoter SNPs--in the IL13 locus on chromosome 5q31 were examined for association, linkage disequilibrium, and interaction. We found that both individual SNPs (IL4R L389L; odds ratio [OR] 0.34; 95% confidence interval [CI] 0.17-0.67; P=.001) and specific haplotypes both in IL4R (OR 0.10; 95% CI 0-0.5; P=.001) and for the five linked IL4 and IL13 SNPs (OR 3.47; P=.004) were strongly associated with susceptibility to T1D. Since IL4 and IL13 both serve as ligands for a receptor composed, in part, of the IL4R alpha chain, we looked for potential epistasis between polymorphisms in the IL4R locus on chromosome 16p11 and the five SNPs in the IL4 and IL13 loci on chromosome 5q31 and found, through use of a logistic-regression model, significant gene-gene interactions (P=.045, corrected for multiple comparisons by permutation analysis). Our data suggest that the risk for T1D is determined, in part, by polymorphisms within the IL4R locus, including promoter and coding-sequence variants, and by specific combinations of genotypes at the IL4R and the IL4 and IL13 loci. 相似文献
113.
Diaz-Ruiz A Vergara P Perez-Severiano F Segovia J Guizar-Sahagún G Ibarra A Ríos C 《Neurochemical research》2005,30(2):245-251
Nitric oxide (NO) plays a role in the pathophysiology of spinal cord injury (SCI). NO is produced by three types of nitric oxide synthase (NOS) enzymes: The constitutive Ca2+/calmodulin-dependent neuronal NOS (nNOS) and endothelial NOS (eNOS) isoforms, and the inducible calcium-independent isoform (iNOS). During the early stages of SCI, nNOS and eNOS produce significant amounts of NO, therefore, the regulation of their activity and expression may participate in the damage after SCI. In the present study, we used Cyclosporin-A (CsA) to further substantiate the role of Ca-dependent NOS in neural responses associated to SCI. Female Wistar rats were subjected to SCI by contusion, and killed 4 h after lesion. Results showed an increase in the activity of constitutive NOS (cNOS) after lesion, inhibited by CsA (2.5 mg/kg i.p.). Western blot assays showed an increased expression of both nNOS and eNOS after trauma, also antagonized by CsA administration. 相似文献
114.
Blanca Montalbán Sarah Croes Nele Weyens M Carmen Lobo Araceli Pérez-Sanz Jaco Vangronsveld 《International journal of phytoremediation》2016,18(10):985-993
The interaction between plant growth-promoting bacteria (PGPB) and plants can enhance biomass production and metal tolerance of the host plants. This work aimed at isolating and characterizing the cultivable bacterial community associated with Brassica napus growing on a Zn-contaminated site, for selecting cultivable PGPB that might enhance biomass production and metal tolerance of energy crops. The effects of some of these bacterial strains on root growth of B. napus exposed to increasing Zn and Cd concentrations were assessed. A total of 426 morphologically different bacterial strains were isolated from the soil, the rhizosphere, and the roots and stems of B. napus. The diversity of the isolated bacterial populations was similar in rhizosphere and roots, but lower in soil and stem compartments. Burkoholderia, Alcaligenes, Agrococcus, Polaromonas, Stenotrophomonas, Serratia, Microbacterium, and Caulobacter were found as root endophytes exclusively. The inoculation of seeds with Pseudomonas sp. strains 228 and 256, and Serratia sp. strain 246 facilitated the root development of B. napus at 1,000 µM Zn. Arthrobacter sp. strain 222, Serratia sp. strain 246, and Pseudomonas sp. 228 and 262 increased the root length at 300 µM Cd. 相似文献
115.
Tomato yellow leaf curl Sardinia virus rep-derived resistance to homologous and heterologous geminiviruses occurs by different mechanisms and is overcome if virus-mediated transgene silencing is activated 总被引:7,自引:0,他引:7 下载免费PDF全文
Lucioli A Noris E Brunetti A Tavazza R Ruzza V Castillo AG Bejarano ER Accotto GP Tavazza M 《Journal of virology》2003,77(12):6785-6798
116.
René E. van Dijk Jennifer C. Kaden Araceli Argüelles‐Ticó L. Marcela Beltran Matthieu Paquet Rita Covas Claire Doutrelant Ben J. Hatchwell 《Journal of avian biology》2013,44(2):102-110
Structures built by animals, such as nests, mounds and burrows, are often the product of cooperative investment by more than one individual. Such structures may be viewed as a public good, since all individuals that occupy them share the benefits they provide. However, access to the benefits generated by the structure may vary among individuals and is likely to be an important determinant of social organisation. Here we use the massive, communal nests of sociable weavers Philetairus socius, to investigate whether their thermoregulatory function varies in relation to the size of communal nests, and the position of individual nest chambers within the communal structure. We then examine whether this spatial variation in thermoregulatory function predicts the social organisation of colonies. First, we show that the sociable weavers’ communal nests buffer variation in ambient temperature, and reduce temperature variability within nest chambers. The extent of this buffering effect depends significantly on the position of nest chambers within the communal structure, and on the depth to which chambers are embedded within the nest mass. We detected no effect of nest volume on thermoregulatory benefits, suggesting that there are likely to be additional, non‐thermoregulatory benefits leading to communal nests. Finally, our results indicate that there may be competition for access to the benefits of the public good, since older birds occupied the chambers with the highest thermoregulatory benefits, where breeding activity was also more common. We discuss how the spatial structure of the benefits of the public good might influence social organisation in the unique communal lifestyle of sociable weavers. 相似文献
117.
Araceli Rivera-Ordaz Susanne Bracher Sannia Sarrach Zheng Li Lei Shi Matthias Quick Daniel Hilger Rainer Haas Heinrich Jung 《PloS one》2013,8(12)
Helicobacter pylori is cause of chronic gastritis, duodenal ulcer and gastric carcinoma in humans. L-proline is a preferred energy source of the microaerophilic bacterium. Previous analyses revealed that HpputP and HpputA, the genes that are predicted to play a central role in proline metabolism as they encode for the proline transporter and proline dehydrogenase, respectively, are essential for stomach colonization. Here, the molecular basis of proline transport in H. pylori by HpPutP was investigated experimentally for the first time. Measuring radiolabeled substrate transport in H. pylori and E. coli heterologously expressing HpputP as well as in proteoliposomes reconstituted with HpPutP, we demonstrate that the observed proline transport in H. pylori is mediated by HpPutP. HpPutP is specific and exhibits a high affinity for L-proline. Notably, L-proline transport is exclusively dependent on Na+ as coupling ion, i.e., Na+/L-proline symport, reminiscent to the properties of PutP of E. coli even though H. pylori lives in a more acidic environment. Homology model-based structural comparisons and substitution analyses identified amino acids crucial for function. HpPutP-catalyzed proline uptake was efficiently inhibited by the known proline analogs 3,4-dehydro-D,L-proline and L-azetidine-2-carboxylic acid. 相似文献
118.
Phytophthora sojae causes root and stem rot, one of the most important diseases of soybean worldwide. Genetic diversity of 32 Phytophthora sojae isolates of different geographic origin from Argentina was evaluated with RAPD markers. The isolates were collected from diseased soybean plants and soil samples from Santa Fe, Buenos Aires, C6rdoba and Entre Rios provinces, in the Pampeana Region. DNA was amplified with 20 decanucleotides primers. Seven primers amplified 49 fragments, of which 35 were polymorphic, indicating high variability. RAPD analysis detected intraspecific variability even among isolates of the same geographic origin. 相似文献
119.
120.
Teresa Villarreal-Molina Carlos Posadas-Romero Sandra Romero-Hidalgo Erika Antúnez-Argüelles Araceli Bautista-Grande Gilberto Vargas-Alarcón Eric Kimura-Hayama Samuel Canizales-Quinteros Juan Gabriel Juárez-Rojas Rosalinda Posadas-Sánchez Guillermo Cardoso-Salda?a Aída Medina-Urrutia María del Carmen González-Salazar Rocío Martínez-Alvarado Esteban Jorge-Galarza Alessandra Carnevale 《PloS one》2012,7(11)