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101.
Martínez H Rodríguez-Larralde A Izaguirre MH De Guerra DC 《Human biology; an international record of research》2007,79(2):201-213
The present Venezuelan population is the product of admixture of Amerindians, Europeans, and Africans, a process that was not homogeneous throughout the country. Blood groups, short tandem repeats (STRs), mtDNA, and Y-chromosome markers have been used successfully in admixture studies, but few such studies have been conducted in Venezuela. In this study we aim to estimate the admixture components of samples from two different socioeconomic levels from Caracas, Venezuela's capital city, compare their differences, and infer sexual asymmetry in the European Amerindian union patterns. Gene frequencies for blood groups ABO and Rh (CDE) and for the STRs VWA, F13A01, and FES/FPS and mtDNA and Y-chromosome haplogroups were studied in a sample of 60 individuals living in Caracas, taken from a private clinic (high socioeconomic level), and 50 individuals, also living in Caracas, drawn from a public maternity clinic (low socioeconomic level). The admixture analysis for the five autosomal markers gives a high European component (0.78) and an almost negligible African sub-Saharan component (0.06) for the high socioeconomic level, whereas for the low socioeconomic level the sub-Saharan, European, and Amerindian components were 0.21, 0.42, and 0.36, respectively. Estimates of admixture based on mtDNA and Y-chromosome markers reveal that the Amerindian contribution to these Caracas samples is almost entirely through females, because the Y-chromosome Amerindian and African sub-Saharan chromosomes found in this study were scarce. Our study reveals that the identification of the grandparents' geographic origin is an important methodological aspect to take into account in genetic studies related to the reconstruction of historical events. 相似文献
102.
Although there is a general understanding of Montagu’s harriers migration routes and wintering areas, detailed information
on the species’ migration is still lacking. However, improvements in satellite tracking technology in recent years, have enabled
the study of medium-sized species by means of satellite telemetry. In 2006, ten adult Montagu’s harriers were fitted with
satellite transmitters in northeastern Spain and tracked during their autumn migration to their wintering grounds in sub-Saharan
Africa. The migration took between 10 and 30 days, and the end point was determined using breakpoint regressions. Whereas
some birds had stopovers of more than a week, others stayed at the same site for only 1 or 2 days at the most. The tagged
birds ultimately established at wintering grounds located along the border of Mauritania with Mali and Senegal, a distance
of nearly 3000 km from the breeding sites. These sites are situated within a small range of latitudes (14° and 17°N), although
distributed over a wider range of longitudes (−15°E and −4°E), with some birds occupying sites more than 1000 km apart. The
distance covered in 1 day during the migration ranged between 93 and 219 km, with peaks of traveling speed of up to 65 km/h.
Harriers were recorded traveling only during daytime, covering the longest distances in the late afternoon, suggesting that
they are daytime migrants. Most of the distance was covered between 1500 and 2000 hours, and no traveling was recorded between
2000 and 0500 hours. During migration, harriers flew close to the ground (40–100 m on average). Improved knowledge of the
harriers’ exact wintering sites may provide insights on the problems Montagu’s harriers face during the winter, highlighting
the need to take into account what happens in both the breeding and wintering grounds to implement successful conservation
measures. 相似文献
103.
Duarte CD Tributino JL Lacerda DI Martins MV Alexandre-Moreira MS Dutra F Bechara EJ De-Paula FS Goulart MO Ferreira J Calixto JB Nunes MP Bertho AL Miranda AL Barreiro EJ Fraga CA 《Bioorganic & medicinal chemistry》2007,15(6):2421-2433
We describe herein the discovery of LASSBio-881 (3c) as a novel in vivo antinociceptive, anti-inflammatory, and in vitro antiproliferative and antioxidant compound, with a cannabinoid ligand profile. We observed that LASSBio-881 (3c) was able to bind to CB1 receptors (71% at 100microM) and also to inhibit T-cell proliferation (66% at 10microM) probably by binding to CB2 receptors, in a non-proapoptotic manner, different from anandamide (1). It was also demonstrated that LASSBio-881 (3c) had an important antioxidant profile toward free radicals (DPPH and hydroxyl), probably due to its particular redox behavior, which reflects the presence of both nitro and 3,5-di-tert-butyl-4-hydroxyphenyl sub-units, as demonstrated by cyclic voltammetry studies. In addition, we showed that these structural sub-units are essential for the observed pharmacological activity. 相似文献
104.
Di Fabio R Alvaro G Bertani B Donati D Pizzi DM Gentile G Pentassuglia G Giacobbe S Spada S Ratti E Corsi M Quartaroli M Barnaby RJ Vitulli G 《Bioorganic & medicinal chemistry letters》2007,17(5):1176-1180
Chiral tetrahydroquinoline derivatives have been prepared by an asymmetric Mannich-type condensation reaction using commercially available vinyloxyethylsilane and a N-arylimino R-(+)-t-butyl lactate ester, in the presence of a catalytic amount of metal triflates as Lewis acids. This synthetic approach gave rise to the target aldehyde intermediate in moderate facial diastereoselectivity and in high chemical yield. This efficient route enabled to scale up the synthesis of an orally bioavailable glycine antagonist showing outstanding in vivo anti-hyperalgesic activity in different animal models of sustained inflammation and chronic neuropathic pain. 相似文献
105.
106.
Stefania Neiva Lavorato Policarpo Ademar Sales Júnior Silvane Maria Fonseca Murta Alvaro José Romanha Ricardo José Alves/ 《Memórias do Instituto Oswaldo Cruz》2015,110(4):566-568
We describe herein the antitrypanosomal activity of 20 novel
1,3-bis(aryloxy)propan-2-amine derivatives. Compounds 2, 4, 6, 12, 15, 16 and 19 were
significantly active against amastigote and trypomastigote forms, with half maximal
inhibitory concentrationvalues in the range of 6-18 µM. In the cytotoxicity tests
against L929 cells, only compound 4 presented selectivity index value above 10,
indicating low toxicity. 相似文献
107.
108.
109.
Yanping Geng Alexej Kedrov Joseph J. Caumanns Alvaro H. Crevenna Don C. Lamb Roland Beckmann Arnold J. M. Driessen 《The Journal of biological chemistry》2015,290(28):17250-17261
Members of the YidC/Oxa1/Alb3 protein family mediate membrane protein insertion, and this process is initiated by the assembly of YidC·ribosome nascent chain complexes at the inner leaflet of the lipid bilayer. The positively charged C terminus of Escherichia coli YidC plays a significant role in ribosome binding but is not the sole determinant because deletion does not completely abrogate ribosome binding. The positively charged cytosolic loops C1 and C2 of YidC may provide additional docking sites. We performed systematic sequential deletions within these cytosolic domains and studied their effect on the YidC insertase activity and interaction with translation-stalled (programmed) ribosome. Deletions within loop C1 strongly affected the activity of YidC in vivo but did not influence ribosome binding or substrate insertion, whereas loop C2 appeared to be involved in ribosome binding. Combining the latter deletion with the removal of the C terminus of YidC abolished YidC-mediated insertion. We propose that these two regions play an crucial role in the formation and stabilization of an active YidC·ribosome nascent chain complex, allowing for co-translational membrane insertion, whereas loop C1 may be involved in the downstream chaperone activity of YidC or in other protein-protein interactions. 相似文献
110.