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131.
Endersby NM Viduka K Baxter SW Saw J Heckel DG McKechnie SW 《Bulletin of entomological research》2011,101(4):393-405
Populations of Plutella xylostella, extending over 3800 km in southern Australia, show no genetic structure as assessed by microsatellite markers; yet outbreaks of pyrethroid resistance occur sporadically in cropping areas. Since mutations in the para voltage-gated sodium channel gene have been implicated in pyrethroid resistance, we looked for DNA sequence variation at this target among Australian moths. We found two resistance mutations previously reported for this species (L1014F and T929I), as well as a novel substitution (F1020S). Of the eight possible haplotypes formed by combinations of these three biallelic polymorphisms, only four were found in Australian populations: the wild-type allele (w), the kdr mutation allele (kdr) with only L1014F, the super-kdr-like combination of L1014F and T929I (skdrl), and the crashdown allele with only F1020S (cdr). Comparison of genotype frequencies among survivors of permethrin assays with those from untreated controls identified three resistant genotypes: skdrl homozygotes, cdr homozygotes and the corresponding heterozygote, cdr/skrdl - the heterozygote being at least as resistant as either homozygote. Spatial heterogeneity of allele frequencies was conspicuous, both across the continent and among local collections, consistent with reported spatial heterogeneity of pyrethroid resistance. Further, high resistance samples were sometimes associated with high frequency of cdr, sometimes high frequency of skdrl, or sometimes with a high combined cdr+skdrl frequency. The skdrl and cdr alleles explain a high proportion of the Australia-wide resistance variation. These data add to evidence that nerve insensitivity by mutations in the para-sodium channel gene is a common pyrethroid resistance mechanism in P. xylostella. 相似文献
132.
Josh Adams Darren Scott Sam McKechnie Grant Blackwell Scott A. Shaffer Henrik Moller 《New Zealand journal of zoology.》2013,40(3):355-366
Abstract We attached 11 g (1.4% body‐mass equivalent) global location sensing (GLS) archival tag packages to tarsi of 25 breeding sooty shearwaters (Puffinus griseus, titi) on Whenua Hou (Codfish Island), New Zealand during the chick‐rearing period in 2005. Compared with chicks reared by non‐handled adults that did not carry tags, deployment of tags on one or both adult parents ultimately resulted in 35% reduction in chick body mass and significantly reduced chick skeletal size preceding fledging (19 April). However, body mass between chick groups was not significantly different after controlling for skeletal size. Effects on chicks were more pronounced in six pairs where both parents carried tags. Chick mass was negatively related to the duration that adults carried tags. In this study, none of the chicks reared by pairs where both parents were tagged, 54% of chicks reared by pairs where one parent was tagged, and 83% of chicks reared by non‐handled and non‐tagged parents achieved a previously determined pre‐fiedging mass threshold (564 g; Sagar & Horning 1998). Body mass of adults carrying tags and returning from trans‐equatorial migration the following year were 4% lighter on average than non‐tagged birds, but this difference was not statistically significant. Reduced mass among chicks reared by adults carrying tags during the chick‐provisioning period indicated that adults altered “normal” provisioning behaviours to maintain their own body condition at the expense of their chicks. Population‐level information derived from telemetry studies can reveal important habitat‐linked behaviours, unique aspects of sea‐bird foraging behaviours, and migration ecology. Information for some species (e.g., overlap with fisheries) can aid conservation and marine ecosystem management. We advise caution, however, when interpreting certain data related to adult provisioning behaviours (e.g., time spent foraging, provisioning rates, etc.). If effects on individuals are of concern, we suggest shorter‐term deployments, smaller and lighter tags, and alternative attachment techniques, especially when investigating threatened or endangered species. 相似文献
133.
Nesreen G Elhelbawy Adel A.H. Nassar Abd ElMonem A Eltorgoman Safa M Saber Eman AE Badr 《Biochemistry and Biophysics Reports》2020
BackgroundNon Hodgkin lymphoma (NHL) is one of the immune system cancers. The occurrence and progression of malignant lymphomas depends on cellular pathways deregulation. Understanding the relationship between the immune system at the genetic level and malignant transformation is critical to reach its etiology.ObjectiveThe aim of this work is to evaluate the expression of five immune related genes (PD-1, FOXP3, GrA, GrB and CD11c) in patients with diffuse large B cell non Hodgkin lymphoma (DLBCL).Materials and methodsThis study was conducted on fifty patients with DLBCL and fifty sex and age matched apparently healthy subjects. The participants were subjected to these laboratory investigations: complete blood count, serum lactate dehydrogenase and β2microglobulin (β2M) levels and determination of PD-1, FOXP3, GrA, GrB and CD11c gene expressions.ResultsThe results of this study revealed that PD-1, FOXP3, GrA, GrB and CD11c gene expressions were significantly increased in DLBCL patients.ConclusionPatients with DLBCL have variablePD-1, FOXP3,GrA, GrB and CD11cgene expressions levels, which are correlated with the overall survival (OS) indicating that they can be good predictors of outcome in these patients. 相似文献
134.
The effect of dietary ethanol on the composition of lipids of Drosophila melanogaster larvae 总被引:4,自引:0,他引:4
At a moderate concentration (2.5%, v/v) dietary ethanol reduced the chain length of total fatty acids (FA) and increased the desaturation of short-chain FA in Drosophila melanogaster larvae with a functional alcohol dehydrogenase (ADH). The changes in length in total FA were postulated to be due to the modulation of the termination specificity of fatty acid synthetase. Because the ethanol-stimulated reduction in the length of unsaturated FA was blocked by linoleic acid, it was thought to reflect the properties of FA 9-desaturase. Although the ethanol-stimulated reduction in chain length of unsaturated FA was also observed in ADH-null larvae, ethanol promoted an increase in the length of total FA of the mutant larvae. Thus, the ethanolstimulated change in FA length was ADH dependent but the ethanol effect on FA desaturation was not. Ethanol also stimulated a decrease in the relative amount of phosphatidylcholine and an increase in phosphatidylethanolamine. Because similar ethanol-induced changes have been found in membrane lipids of other animals, ethanol may alter the properties of membranes in larvae. It is proposed that ethanol tolerance in D. melanogaster may be dependent on genes that specify lipids that are resistant to the detrimental effects of ethanol.This research was supported by National Institutes of Health Grant GM-28779 to B.W.G. and a Monash University Research Grant to S.W.M. 相似文献
135.
Camilla F. Speller Lorenz Hauser Dana Lepofsky Jason Moore Antonia T. Rodrigues Madonna L. Moss Iain McKechnie Dongya Y. Yang 《PloS one》2012,7(11)
Pacific herring (Clupea pallasi) are an abundant and important component of the coastal ecosystems for the west coast of North America. Current Canadian federal herring management assumes five regional herring populations in British Columbia with a high degree of exchange between units, and few distinct local populations within them. Indigenous traditional knowledge and historic sources, however, suggest that locally adapted, distinct regional herring populations may have been more prevalent in the past. Within the last century, the combined effects of commercial fishing and other anthropogenic factors have resulted in severe declines of herring populations, with contemporary populations potentially reflecting only the remnants of a previously more abundant and genetically diverse metapopulation. Through the analysis of 85 archaeological herring bones, this study attempted to reconstruct the genetic diversity and population structure of ancient herring populations using three different marker systems (mitochondrial DNA (mtDNA), microsatellites and SNPs). A high success rate (91%) of DNA recovery was obtained from the extremely small herring bone samples (often <10 mg). The ancient herring mtDNA revealed high haplotype diversity comparable to modern populations, although population discrimination was not possible due to the limited power of the mtDNA marker. Ancient microsatellite diversity was also similar to modern samples, but the data quality was compromised by large allele drop-out and stuttering. In contrast, SNPs were found to have low error rates with no evidence for deviations from Hardy-Weinberg equilibrium, and simulations indicated high power to detect genetic differentiation if loci under selection are used. This study demonstrates that SNPs may be the most effective and feasible approach to survey genetic population structure in ancient remains, and further efforts should be made to screen for high differentiation markers.This study provides the much needed foundation for wider scale studies on temporal genetic variation in herring, with important implications for herring fisheries management, Aboriginal title rights and herring conservation. 相似文献
136.
137.
Evelyn Schenfeld S. W. McKechnie 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1979,54(5):235-237
Summary As a test of the hypothesis that adult temperature stress is an important component of natural selection maintaining the -gpdh polymorphism, we have looked for differential survival among genotypes subjected to (i) heat shock and (ii) cold shock. Factorial ANOVAR, taking account of genotype, sex and temperature-stress indicated that genotype did not contribute to the variance of survival proportion per vial. We have not therefore found evidence to support our hypothesis. Incidental to the above was a significant sex-temperature interaction. Thus, adult females showed higher survival than males under heat stress, while under cold stress, there was no indication of a survival difference between the sexes. 相似文献
138.
SHIGERU A. AE 《Systematic Entomology》1979,4(1):1-16
Abstract. Adults of different species of the genus Papilio can easily be mated by hand-pairing. The data on egg hatchability, adult formation and F1 fertility in these interspecific hybrids show notable variations according to the crosses. Using these data, values of a differentiation index for each cross were calculated. These estimates of genetic distance were then used to study the phylo-genetic relationships of the species involved. The data are consistent with the existence of the following groups, each consisting of closely related species: the black Papilio supergroup, the Papilio memnon group, the P.demoleus group, the P.xuthus group, the P.machaon group, the P.bianor group, the P.glaucus group and the P.troilus group. The phylogenetic relationships revealed by these data generally coincide with the relationships established by classical taxonomy. In cases where there are differences of opinion among taxonomists, the writer's data usually support one or other of them. 相似文献
139.
140.
Max A Little Patrick E McSharry Stephen J Roberts Declan AE Costello Irene M Moroz 《Biomedical engineering online》2007,6(1):23