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961.
In the area of genometry—the nascent field of science and technology that proposes to apply enhanced understanding of the human genetic code to reshaping our individual and collective destinies—no topic has generated more interest among the general public, as well as in the athletic community, than the potential for physical enhancement of the human body and its performance. Genometric experiments have produced physically enhanced mice, and the production of similarly enhanced humans may not be far off. Although it is not the objective of most genometric research, the day will come when gene-based “treatments” will enable individuals to build muscle or increase endurance faster than is possible through conventional methods. This article describes developments in the area of physical enhancement that may find application in the “gene doping” of athletes. For example, human performance-related genes may be delivered to athletes using tools developed for research in gene therapy; the protein products of these genes may be administered in recombinant form; and recently discovered small-molecule activators of the major genetic regulatory pathways of physical prowess may be taken orally, providing “exercise in a pill”. This article also describes US and international attempts to regulate and punish the use of prohibited techniques for performance enhancement among athletes. As science advances, defining and detecting “gene doping” becomes increasingly complex. Thus, the study of physical enhancement provides an ideal starting point for the interdisciplinary Redefined Destinies Colloquium's examination of the intersection between law and science. 相似文献
962.
Andoniaina R. Andrianaivoarivelo Gary D. Shore Susie M. McGuire Richard K. B. Jenkins Olga Ramilijaona Edward E. Louis Jr. Rick A. Brenneman 《Conservation Genetics》2009,10(4):1025-1028
Twenty-two nuclear microsatellite loci were isolated from a genomic DNA library derived from Madagascar’s Rousettus madagascariensis. Marker characteristics were determined from a single population (37 individuals) from Fort Dauphin (southeastern Madagascar).
Sixteen of the 22 loci were within Hardy–Weinberg expectations. These loci are highly informative with polymorphic information
content values ranging between 0.757 and 0.916. These loci will provide valuable information for the study of population genetics
and gene flow within this species of bats. Due to the dramatic reduction and alteration of their habitat, data generated utilizing
this marker suite will potentially provide additional information for the effective long-term management of this near-threatened
bat species. 相似文献
963.
Wendy A. Lea Jin Xi Ajit Jadhav Louis Lu Christopher P. Austin Anton Simeonov Roderic G. Eckenhoff 《PloS one》2009,4(9)
Anesthetic development has been a largely empirical process. Recently, we described a GABAergic mimetic model system for anesthetic binding, based on apoferritin and an environment-sensitive fluorescent probe. Here, a competition assay based on 1-aminoanthracene and apoferritin has been taken to a high throughput screening level, and validated using the LOPAC1280 library of drug-like compounds. A raw hit rate of ∼15% was reduced through the use of computational filters to yield an overall hit rate of ∼1%. These hits were validated using isothermal titration calorimetry. The success of this initial screen and computational triage provides feasibility to undergo a large scale campaign to discover novel general anesthetics. 相似文献
964.
Rosemary Oh-McGinnis Aaron B Bogutz Kang Yun Lee Michael J Higgins Louis Lefebvre 《BMC developmental biology》2010,10(1):50
Background
Several imprinted genes have been implicated in the process of placentation. The distal region of mouse chromosome 7 (Chr 7) contains at least ten imprinted genes, several of which are expressed from the maternal homologue in the placenta. The corresponding paternal alleles of these genes are silenced in cis by an incompletely understood mechanism involving the formation of a repressive nuclear compartment mediated by the long non-coding RNA Kcnq1ot1 initiated from imprinting centre 2 (IC2). However, it is unknown whether some maternally expressed genes are silenced on the paternal homologue via a Kcnq1ot1-independent mechanism. We have previously reported that maternal inheritance of a large truncation of Chr7 encompassing the entire IC2-regulated domain (DelTel7 allele) leads to embryonic lethality at mid-gestation accompanied by severe placental abnormalities. Kcnq1ot1 expression can be abolished on the paternal chromosome by deleting IC2 (IC2KO allele). When the IC2KO mutation is paternally inherited, epigenetic silencing is lost in the region and the DelTel7 lethality is rescued in compound heterozygotes, leading to viable DelTel7/IC2KO mice. 相似文献965.
Alcoholic extracts from bark of Calocedrus macrolepis var. formosana Florin (Cupressaceae) were extracted successively using n-hexane, dichloromethane, ethyl acetate, 1-butanol and water, which gave 34.8%, 34.1%, 24.1%, 3.3% and 3.7% soluble fractions, respectively. Antioxidation activity of these fractions by DPPH assay and dissimilar IC50 values of the DPPH showed that ethyl acetate fraction had the best antioxidant activity; its IC50 was 2.6 microg/ml. Analyses of the composition and anti-inflammatory activity of the subfractions from n-C6H14 fraction showed that the T3 and H5ppt had the best anti-inflammatory activity in LPS-stimulated murine macrophage J774A. 1 cells, respectively; moreover, their major constituent was sugiol (T3 37.1%, H5ppt 81.1%), which at dosages of 10 microg/ml inhibited proIL-1beta protein production completely. Furthermore, the T1 also exhibited anti-inflammatory activity, and its major constituent was ferruginol (above 85.6%). 相似文献
966.
Parmakelis A Stathi I Chatzaki M Simaiakis S Spanos L Louis C Mylonas M 《Molecular ecology》2006,15(10):2883-2894
Sequence data derived from two mitochondrial markers, 16S rRNA and COI genes, were used to infer the evolutionary history of 47 insular and mainland populations covering most of the distributional range of the northeastern Mediterranean scorpion species Mesobuthus gibbosus. Based on the estimated divergence times of Mesobuthus lineages, the temporal frame of the genus differentiation in the northeastern Mediterranean region is placed in middle Miocene (15 million years ago). The biogeographic affinities of M. gibbosus populations point towards a mainly vicariant pattern of differentiation of the species which is consistent with the geological events that transformed the Aegean region during the period from 12 to 5 million years ago. M. gibbosus is an old northeastern Mediterranean species that has retained valuable bits of genetic information, reflecting some of the oldest vicariant events that have occurred in the area. Most importantly, the history witnessed by M. gibbosus has not been obscured by more recent palaeoevents of the region. Therefore, the case of M. gibbosus is in favour of a taxon-oriented 'perception' of the natural history of a given area. 相似文献
967.
The evolutionary potential of a species is determined by its genetic diversity. Thus, management plans should integrate genetic concerns into active conservation efforts. The copper redhorse (Moxostoma hubbsi) is an endangered species, with an endemic distribution limited to the Richelieu River and a short section of the St Lawrence River in Quebec, Canada. The population, gradually fragmented since 1849, is characterized by a decline in population size and a lack of recruitment. A total of 269 samples were collected between 1984 and 2004 and genotyped using 22 microsatellite loci, which indicated that these fish comprise a single population, with a global F(ST) value of only 0.0038. Despite a small census size ( approximately 500), a high degree of genetic diversity was observed compared to common values for freshwater fishes (average number of 12.5 alleles/locus and average HO of 0.77 +/- 0.08). No difference was observed between expected and observed pairwise values of relatedness (r(xy): -0.00013 +/- 0.11737), suggesting an outbred population. Long-term Ne was estimated at 4476 whereas contemporary Ne values ranged from 107 to 568, suggesting a pronounced yet gradual demographic decline of the population, as no bottleneck could be detected for the recent past. By means of simulations, we estimated Ne would need to remain at more than approximately 400 to retain 90% of the genetic diversity over 100 years. Overall, these observations corroborate other recent empirical studies confirming that long generation times may act as a buffering effect contributing to a reduction in the pace of genetic diversity erosion in threatened species. 相似文献
968.
Moita LF Vriend G Mahairaki V Louis C Kafatos FC 《Insect biochemistry and molecular biology》2006,36(4):282-290
Mosquitoes use effective immune responses, including phagocytosis, to fight microbial infection. Here we show that in an Anopheles gambiae immune responsive cell line, RGD recognizing receptors play an important role in the phagocytic response, suggesting overlap between molecular components implicated in adhesion and phagocytosis. Integrins are a major class of adhesive receptors that recognize ligands containing an RGD motif. We have cloned a gene encoding a new beta integrin, BINT2, and demonstrated its involvement in Escherichia coli engulfment. Based on molecular modeling, we propose a structural reason for the role of BINT2, but not BINT1, on phagocytosis of Gram-negative bacteria. Using bioinformatic tools, we have identified and compared the complete A. gambiae integrin repertoire as a prelude to a future systematic functional study. 相似文献
969.
Anopheles gambiae immune responses to Sephadex beads: involvement of anti-Plasmodium factors in regulating melanization 总被引:3,自引:0,他引:3
Warr E Lambrechts L Koella JC Bourgouin C Dimopoulos G 《Insect biochemistry and molecular biology》2006,36(10):769-778
We have performed a global genome expression analysis of mosquito responses to CM-25 Sephadex beads and identified 27 regulated immune genes, including several anti-Plasmodium factors and other components with likely roles in melanization. Silencing of two bead injection responsive genes, TEP1 and LRIM1, which encode proteins known to mediate Plasmodium killing, significantly compromised the ability to melanize the beads. In contrast, silencing of two Plasmodium protective c-type lectins, CTL4 and CTLMA2, did not affect bead melanization. This data suggest that the anti-Plasmodium factors have dual functions, as determinants of both Plasmodium killing and melanization of the parasite and other foreign bodies, while the Plasmodium protective factors are specifically utilized by the parasite for evasion of mosquito defense mechanisms. 相似文献
970.
Crane L Anastassiadou M El Hage S Stigliani JL Baziard-Mouysset G Payard M Leger JM Bizot-Espiard JG Ktorza A Caignard DH Renard P 《Bioorganic & medicinal chemistry》2006,14(22):7419-7433
Imidazoline derivatives have been reported to show antihyperglycemic activity in vivo. In the present study, we first showed that there was no correlation between the in vivo antidiabetic activity and the in vitro affinities for the I1/I2 binding sites for several substituted aryl imidazolines. Among these compounds, 2-(alpha-cyclohexyl-benzyl)-4,5-dihydro-1H-imidazole 2 exhibited potent antihyperglycemic properties. It was then chosen as lead compound. Thirty-six new derivatives were synthesized by replacing the cyclohexyl/benzyl group by various cyclic systems or the imidazoline ring by isosteric heterocycles. These compounds were evaluated in vivo for their antihyperglycemic activity using an oral glucose tolerance test (OGTT) in a rat model of type-2 diabetes obtained by giving a single intravenous (iv) injection of a low dose of streptozotocin to rats (STZ rats) and in normal rats. Nine compounds with an imidazoline moiety, possibly substituted by a methyl group, had a potent effect on the glucose tolerance in normal or STZ-diabetic rats, after an oral (po) administration of the test compound at a dose of 30 or 10 mg kg(-1), without any hypoglycemia. Replacement of the imidazoline ring by isosteric heterocycles resulted in a total loss of activity. 相似文献