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1.
Goicoechea AS Carnese FR Dejean C Avena SA Weimer TA Franco MH Callegari-Jacques SM Estalote AC Simões ML Palatnik M Salzano FM 《American journal of physical anthropology》2001,115(2):133-143
A total of 495 individuals from five different Argentinian tribes was examined for variation in 23 blood group and protein genetic systems, and the results were integrated with previous data on some of these systems. These tribes generally present RH * R1, PGM1 * 1, and ACP * A frequencies lower and RH * R2, ESD * 1, and GLO * 1 prevalences higher than those observed in other South American Indian groups. Earlier studies with mitochondrial DNA showed that haplogroup A was present in low frequencies in these tribes, but haplogroup B showed a high prevalence among the Mataco. Average heterozygosities are very similar in the five tribes, while estimates of non-Indian ancestry are generally low. Both the blood group and protein, as well as the mtDNA data sets, divide the five tribes into two groups, and the relationships obtained with the blood group and protein systems are exactly those expected on the basis of geography and language. However, the topology obtained with the mtDNA results was different, possibly due to sampling effects or diverse patterns of exchange between the groups related to sex. 相似文献
2.
Girón R Abalo R Goicoechea C Martín MI Callado LF Cano C Goya P Jagerovic N 《Life sciences》2002,71(9):1023-1034
Three new fentanyl analogs (compounds 3-4-5) have been synthesized and evaluated for antinociceptive properties using the writhing test. The analgesic property of the active compound, N-[1-phenylpyrazol-3-yl]-N-[1-(2-phenethyl)-4-piperidyl)] propenamide (compound 4), was tested using the hot plate test in mice. Its opioid agonistic activity was characterized using three isolated tissues: guinea pig ileum, mouse vas deferens, and rabbit vas deferens. Compound 4 was as effective as fentanyl or morphine and it showed less antinociceptive potency than fentanyl but it was more potent than morphine. The duration of the antinociception was similar to that of fentanyl. This compound inhibited the electrically evoked contractions of myenteric plexus-longitudinal muscle strips of guinea pig ileum and of mouse vas deferens but not those of rabbit vas deferens. These effects could be reversed by micro selective antagonists (naloxone and/or CTOP) but not by the delta selective antagonist naltrindole, thus indicating that the compound acted as a micro opioid agonist. Finally, the binding data confirmed that compound 4 had high affinity and selectivity for the micro-receptor. 相似文献
3.
Montero A Goya P Jagerovic N Callado LF Meana JJ Girón R Goicoechea C Martín MI 《Bioorganic & medicinal chemistry》2002,10(4):1009-1018
Derivatives of N-(1-phenethyl-4-piperidyl)propanamides incorporating guanidinium and 2-aminoimidazolinium groups have been prepared by a synthetic approach involving first introduction of a spacer between the piperidine and the functional group by reductive amination of piperidinone. The formation of each of these functional groups was carried out using N-N'-di(tert-butoxycarbonyl)thiourea and 2-methylthioimidazolinium iodide, respectively. These structures have been designed to incorporate two pharmacologic goals into one entity. Radioligand binding assays have been used to study their affinity for opioid (mu, delta and kappa) and I2-imidazoline receptors. Two of them, 10 and 16, showed high affinity for mu opioid receptors and functionally they had moderate analgesic properties in the hot plate and writhing tests. The in vitro studies on guinea pig ileum (GPI) indicated that both compounds are mu opioid agonists. In what concerns I2-imidazoline receptor activity, these derivatives showed low affinity around 6 to 7 times less than idazoxan. 相似文献
4.
Iván Closa Juan José Irigoyen Nieves Goicoechea 《Trees - Structure and Function》2010,24(6):1029-1043
Beech forests naturally regenerating from clear-cutting can exhibit different microclimates depending on size of saplings
and stem density. When beech trees are young and stem density is low, the level of radiation inside the ecosystem reaching
the soil surface is high; consequently, air and soil temperatures rise and the soil water content may decrease. These microclimatic
parameters presumably will affect the anatomy, photosynthesis, and carbon metabolism of beech leaves. We studied the morphology
and physiology of sun and shade leaves of beech trees differing in age and growing within clear-cut areas with distinct microclimate.
Results were compared with those of adult trees in an unmanaged forest. We selected a stand clear-cut in 2001 (14,000 trees
ha−1), another clear-cut in 1996 (44,000 trees ha−1) and an unmanaged forest (1,000 trees ha−1). Photosynthetic photon flux density (PPFD) incident on sun leaves, air temperature, soil moisture, and soil temperature
within the forests affected water status and carbohydrate storage in all trees. As trees became older, PPFD also influenced
pigment composition and Rubisco activity in sun leaves. On the other hand, shade leaves from the oldest trees were the most
sensitive to PPFD, air temperature, and soil moisture and temperature inside the forest. Contrariwise, microclimatic parameters
slightly affected the physiology of shade leaves of the beech in the stand with the highest light attenuation. Air and soil
temperatures were the parameters that most affected the photosynthetic pigments and carbohydrate storage in shade leaves of
the youngest trees. 相似文献
5.
Zuccolo A Bowers JE Estill JC Xiong Z Luo M Sebastian A Goicoechea JL Collura K Yu Y Jiao Y Duarte J Tang H Ayyampalayam S Rounsley S Kudrna D Paterson AH Pires JC Chanderbali A Soltis DE Chamala S Barbazuk B Soltis PS Albert VA Ma H Mandoli D Banks J Carlson JE Tomkins J dePamphilis CW Wing RA Leebens-Mack J 《Genome biology》2011,12(5):R48-14
Background
Recent phylogenetic analyses have identified Amborella trichopoda, an understory tree species endemic to the forests of New Caledonia, as sister to a clade including all other known flowering plant species. The Amborella genome is a unique reference for understanding the evolution of angiosperm genomes because it can serve as an outgroup to root comparative analyses. A physical map, BAC end sequences and sample shotgun sequences provide a first view of the 870 Mbp Amborella genome.Results
Analysis of Amborella BAC ends sequenced from each contig suggests that the density of long terminal repeat retrotransposons is negatively correlated with that of protein coding genes. Syntenic, presumably ancestral, gene blocks were identified in comparisons of the Amborella BAC contigs and the sequenced Arabidopsis thaliana, Populus trichocarpa, Vitis vinifera and Oryza sativa genomes. Parsimony mapping of the loss of synteny corroborates previous analyses suggesting that the rate of structural change has been more rapid on lineages leading to Arabidopsis and Oryza compared with lineages leading to Populus and Vitis. The gamma paleohexiploidy event identified in the Arabidopsis, Populus and Vitis genomes is shown to have occurred after the divergence of all other known angiosperms from the lineage leading to Amborella.Conclusions
When placed in the context of a physical map, BAC end sequences representing just 5.4% of the Amborella genome have facilitated reconstruction of gene blocks that existed in the last common ancestor of all flowering plants. The Amborella genome is an invaluable reference for inferences concerning the ancestral angiosperm and subsequent genome evolution. 相似文献6.
Ammiraju JS Yu Y Luo M Kudrna D Kim H Goicoechea JL Katayose Y Matsumoto T Wu J Sasaki T Wing RA 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,111(8):1596-1607
The International Rice Genome Sequencing Project has recently announced the high-quality finished sequence that covers nearly
95% of the japonica rice genome representing 370 Mbp. Nevertheless, the current physical map of japonica rice contains 62 physical gaps corresponding to approximately 5% of the genome, that have not been identified/represented
in the comprehensive array of publicly available BAC, PAC and other genomic library resources. Without finishing these gaps,
it is impossible to identify the complete complement of genes encoded by rice genome and will also leave us ignorant of some
5% of the genome and its unknown functions. In this article, we report the construction and characterization of a tenfold
redundant, 40 kbp insert fosmid library generated by random mechanical shearing. We demonstrated its utility in refining the
physical map of rice by identifying and in silico mapping 22 gap-specific fosmid clones with particular emphasis on chromosomes
1, 2, 6, 7, 8, 9 and 10. Further sequencing of 12 of the gap-specific fosmid clones uncovered unique rice genome sequence
that was not previously reported in the finished IRGSP sequence and emphasizes the need to complete finishing of the rice
genome.
Fosmid library reported here is publicly available from our web site 相似文献
7.
Fejerman L Carnese FR Goicoechea AS Avena SA Dejean CB Ward RH 《American journal of physical anthropology》2005,128(1):164-170
The population of Argentina today does not have a “visible” black African component. However, censuses conducted during most of the 19th century registered up to 30% of individuals of African origin living in Buenos Aires city. What has happened to this African influence? Have all individuals of African origin died, as lay people believe? Or is it possible that admixture with the European immigrants made the African influence “invisible?” We investigated the African contribution to the genetic pool of the population of Buenos Aires, Argentina, typing 12 unlinked autosomal DNA markers in a sample of 90 individuals. The results of this analysis suggest that 2.2% (SEM = 0.9%) of the genetic ancestry of the Buenos Aires population is derived from Africa. Our analysis of individual admixture shows that those alleles that have a high frequency in populations of African origin tend to concentrate among 8 individuals in our sample. Therefore, although the admixture estimate is relatively low, the actual proportion of individuals with at least some African influence is approximately 10%. The evidence we are presenting of African ancestry is consistent with the known historical events that led to the drastic reduction of the Afro‐Argentine population during the second half of the 19th century. However, as our results suggest, this reduction did not mean a total disappearance of African genes from the genetic pool of the Buenos Aires population. Am J Phys Anthropol 128:164‐170, 2005. © 2005 Wiley‐Liss, Inc. 相似文献
8.
Scotti-Saintagne C Mariette S Porth I Goicoechea PG Barreneche T Bodénès C Burg K Kremer A 《Genetics》2004,168(3):1615-1626
Interspecific differentiation values (G(ST)) between two closely related oak species (Quercus petraea and Q. robur) were compiled across different studies with the aim to explore the distribution of differentiation at the genome level. The study was based on a total set of 389 markers (isozymes, AFLPs, SCARs, microsatellites, and SNPs) for which allelic frequencies were estimated in pairs of populations sampled throughout the sympatric distribution of the two species. The overall distribution of G(ST) values followed an L-shaped curve with most markers exhibiting low species differentiation (G(ST) < 0.01) and only a few loci reaching >10% levels. Twelve percent of the loci exhibited significant G(ST) deviations to neutral expectations, suggesting that selection contributed to species divergence. Coding regions expressed higher differentiation than noncoding regions. Among the 389 markers, 158 could be mapped on the 12 linkage groups of the existing Q. robur genetic map. Outlier loci with large G(ST) values were distributed over 9 linkage groups. One cluster of three outlier loci was found within 0.51 cM; but significant autocorrelation of G(ST) was observed at distances <2 cM. The size and distribution of genomic regions involved in species divergence are discussed in reference to hitchhiking effects and disruptive selection. 相似文献
9.
Jagerovic N Cano C Elguero J Goya P Callado LF Meana JJ Girón R Abalo R Ruiz D Goicoechea C Martín MA 《Bioorganic & medicinal chemistry》2002,10(3):817-827
The synthesis of new fentanyl analogues in which the benzene ring of the propioanilido group has been replaced by phenylpyrazole is described. Antinociceptive activity was evaluated using the writhing and hot plate tests in mice. Two compounds, and, showed interesting analgesic properties, being more potent than morphine and less than fentanyl but with longer duration of action. These compounds inhibited the electrically evoked muscle contraction of guinea pig ileum and mouse vas deferens but not that of rabbit vas deferens and the effects could be reversed by antagonists (naloxone and/or CTOP), thus indicating that the compounds acted as mu agonists. Finally, the binding data confirmed that the compounds had high affinity and selectivity for the mu receptor. 相似文献
10.
The influence of mycorrhizal symbiosis, atmospheric CO2 concentration and the interaction between both factors on biomass production and partitioning were assessed in nodulated alfalfa (Medicago sativa L.) associated or not with arbuscular mycorrhizal fungi (AMF) and grown in greenhouse at either ambient (392 μmol?mol?1) or elevated (700 μmol?mol?1) CO2 air concentrations. Measurements were performed at three stages of the vegetative period of plants. Shoot and root biomass achieved by plants at the end of their vegetative period were highly correlated to the photosynthetic rates reached at earlier stages, and there was a significant relationship between CO2 exchange rates and total nodule biomass per plant. In non-mycorrhizal alfalfa, the production of leaves, stems and nodules biomass significantly increased when plants had been exposed to elevated CO2 concentration in the atmosphere for 4 weeks. Regardless CO2 concentration at which alfalfa were cultivated, mycorrhizal symbiosis improved photosynthetic rates and growth of alfalfa at early stages of the vegetative period and then photosynthesis decreased, which suggests that AMF shortened the vegetative period of the host plants. At final stages of the vegetative period, AMF enhanced both area and biomass of leaves as well as the leaves to stems ratio when alfalfa plants were cultivated at ambient CO2. The interaction of AMF with elevated CO2 improved root biomass and slightly increased the leaves to stems ratio at the end of the vegetative growth. Therefore, AMF may favor both the forage quality of alfalfa when grown at ambient CO2 and its perennity for next cutting regrowth cycle when grown under elevated CO2. Nevertheless, this hypothesis needs to be checked under natural conditions in field. 相似文献