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111.
ARNE MOKSNES EIVIN RØSKAFT LISE GREGER HAGEN MARCEL HONZA CECILIE MØRK PER H. OLSEN 《Ibis》2000,142(2):247-258
This study is based on continuous video recordings made at 53 Reed Warbler Acrocephalus scirpaceus nests each day during the laying period. Egg-laying by the Common Cuckoo Cuculus canorus was recorded in 14 (26.4%) of these nests. By analysing the activity of the host birds around and at the nest, we found that this is probably not the only cue used by the Common Cuckoo when locating suitable nests to parasitize. Furthermore, in most cases there was no significant difference between the length of time the host birds spent at the nest in the morning and afternoon, thus providing little support for the hypothesis that the Common Cuckoo lays in the afternoon because it is less likely to be seen by the nest owners then. Parasitized Reed Warblers rejected the Common Cuckoo egg more frequently when they observed the parasite at their nests. However, contrary to what should be expected, most Common Cuckoos laid their eggs in the presence of the host(s), and in general their egg-laying behaviour (for example duration of stay at the nest) was less secretive than described earlier. When partially depredating host clutches, Cuckoos showed the same behavioural pattern at parasitized and unparasitized nests, indicating that the latter may act as a potential reserve for egg-laying. 相似文献
112.
Jarvis DE Kopp OR Jellen EN Mallory MA Pattee J Bonifacio A Coleman CE Stevens MR Fairbanks DJ Maughan PJ 《Journal of genetics》2008,87(1):39-51
Quinoa is a regionally important grain crop in the Andean region of South America. Recently quinoa has gained international attention for its high nutritional value and tolerances of extreme abiotic stresses. DNA markers and linkage maps are important tools for germplasm conservation and crop improvement programmes. Here we report the development of 216 new polymorphic SSR (simple sequence repeats) markers from libraries enriched for GA, CAA and AAT repeats, as well as 6 SSR markers developed from bacterial artificial chromosome-end sequences (BES-SSRs). Heterozygosity (H) values of the SSR markers ranges from 0.12 to 0.90, with an average value of 0.57. A linkage map was constructed for a newly developed recombinant inbred lines (RIL) population using these SSR markers. Additional markers, including amplified fragment length polymorphisms (AFLPs), two 11S seed storage protein loci, and the nucleolar organizing region (NOR), were also placed on the linkage map. The linkage map presented here is the first SSR-based map in quinoa and contains 275 markers, including 200 SSR. The map consists of 38 linkage groups (LGs) covering 913 cM. Segregation distortion was observed in the mapping population for several marker loci, indicating possible chromosomal regions associated with selection or gametophytic lethality. As this map is based primarily on simple and easily-transferable SSR markers, it will be particularly valuable for research in laboratories in Andean regions of South America. 相似文献
113.
Background
Previously it has been shown that insulin-mediated tyrosine phosphorylation of myosin heavy chain is concomitant with enhanced association of C-terminal SRC kinase during skeletal muscle differentiation. We sought to identify putative site(s) for this phosphorylation event. 相似文献114.
Marije Oosting Kathrin Buffen Subbarao RK Malireddi Patrick Sturm Ineke Verschueren Marije I Koenders Frank L van de Veerdonk Jos WM van der Meer Mihai G Netea Thirumala-Devi Kanneganti Leo AB Joosten 《Arthritis research & therapy》2012,14(6):R247
Introduction
The protein platform called the NOD-like-receptor -family member (NLRP)-3 inflammasome needs to be activated to process intracellular caspase-1. Active caspase-1 is able to cleave pro-Interleukin (IL)-1β, resulting in bioactive IL-1β. IL-1β is a potent proinflammatory cytokine, and thought to play a key role in the pathogenesis of Lyme arthritis, a common manifestation of Borrelia burgdorferi infection. The precise pathways through which B. burgdorferi recognition leads to inflammasome activation and processing of IL-1β in Lyme arthritis has not been elucidated. In the present study, we investigated the contribution of several pattern recognition receptors and inflammasome components in a novel murine model of Lyme arthritis.Methods
Lyme arthritis was elicited by live B. burgdorferi, injected intra-articularly in knee joints of mice. To identify the relevant pathway components, the model was applied to wild-type, NLRP3-/-, ASC-/-, caspase-1-/-, NOD1-/-, NOD2-/-, and RICK-/- mice. As a control, TLR2-/-, Myd88-/- and IL-1R-/- mice were used. Peritoneal macrophages and bone marrow-derived macrophages were used for in vitro cytokine production and inflammasome activation studies. Joint inflammation was analyzed in synovial specimens and whole knee joints. Mann-Whitney U tests were used to detect statistical differences.Results
We demonstrate that ASC/caspase-1-driven IL-1β is crucial for induction of B. burgdorferi-induced murine Lyme arthritis. In addition, we show that B. burgdorferi-induced murine Lyme arthritis is less dependent on NOD1/NOD2/RICK pathways while the TLR2-MyD88 pathway is crucial.Conclusions
Murine Lyme arthritis is strongly dependent on IL-1 production, and B. burgdorferi induces inflammasome-mediated caspase-1 activation. Next to that, murine Lyme arthritis is ASC- and caspase-1-dependent, but NLRP3, NOD1, NOD2, and RICK independent. Also, caspase-1 activation by B. burgdorferi is dependent on TLR2 and MyD88. Based on present results indicating that IL-1 is one of the major mediators in Lyme arthritis, there is a rationale to propose that neutralizing IL-1 activity may also have beneficial effects in chronic Lyme arthritis. 相似文献115.
Anna J. Jasinska Susan Service Matthew Levinson Erin Slaten Oliver Lee Eric Sobel Lynn A. Fairbanks Julia N. Bailey Matthew J. Jorgensen Sherry E. Breidenthal Ken Dewar Thomas J. Hudson Roberta Palmour Nelson B. Freimer Roel A. Ophoff 《Mammalian genome》2007,18(5):347-360
The spectacular progress in genomics increasingly highlights the importance of comparative biology in biomedical research.
In particular, nonhuman primates, as model systems, provide a crucial intermediate between humans and mice. The close similarities
between humans and other primates are stimulating primate studies in virtually every area of biomedical research, including
development, anatomy, physiology, immunology, and behavior. The vervet monkey (Chlorocebus aethiops sabaeus) is an important model for studying human diseases and complex traits, especially behavior. We have developed a vervet genetic
linkage map to enable mapping complex traits in this model organism and facilitate comparative genomic analysis between vervet
and other primates. Here we report construction of an initial genetic map built with about 360 human orthologous short tandem
repeats (STRs) that were genotyped in 434 members of an extended vervet pedigree. The map includes 226 markers mapped in a
unique order with a resolution of 9.8 Kosambi centimorgans (cM) in the vervet monkey genome, and with a total length (including
all 360 markers) of 2726 cM. At least one complex and 11 simple rearrangements in marker order distinguish vervet chromosomes
from human homologs. While inversions and insertions can explain a similar number of changes in marker order between vervet
and rhesus homologs, mostly inversions are observed when vervet chromosome organization is compared to that in human and chimpanzee.
Our results support the notion that large inversions played a less prominent role in the evolution within the group of the
Old World monkeys compared to the human and chimpanzee lineages.
Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. 相似文献
116.
Membrane proteins were fractionated electrophoretically in polyacrylamide gels containing either anionic or cationic detergent at either pH 2.4 or 8.3. In all four systems, polypeptides migrated as monomers bearing the charge of the detergent ion and semi-logarithmic molecular weight–mobility relationships pertained. Electrophoresis of erythrocyte membrane proteins in these systems yielded very similar protein staining patterns but revealed significant differences in sialoglycoprotein migration. 相似文献
117.
Electrophoretic analysis of the major polypeptides of the human erythrocyte membrane 总被引:1012,自引:0,他引:1012
118.
Diabetes mellitus is a heterogeneous metabolic disorder characterized by hyperglycaemia resulting in defective insulin secretion,
resistance to insulin action or both. The use of biguanides, sulphonylurea and other drugs are valuable in the treatment of
diabetes mellitus; their use, however, is restricted by their limited action, pharmaco-kinetic properties, secondary failure
rates and side effects. Trigonella foenum-graecum, commonly known as fenugreek, is a plant that has been extensively used as a source of antidiabetic compounds from its seeds
and leaf extracts. Preliminary human trials and animal experiments suggest possible hypoglycaemic and anti-hyperlipedemic
properties of fenugreek seed powder taken orally. Our results show that the action of fenugreek in lowering blood glucose
levels is almost comparable to the effect of insulin. Combination with trace metal showed that vanadium had additive effects
and manganese had additive effects with insulin on in vitro system in control and diabetic animals of young and old ages using adipose tissue. The Trigonella and vanadium effects were studied in a number of tissues including liver, kidney, brain peripheral nerve, heart, red blood
cells and skeletal muscle. Addition of Trigonella to vanadium significantly removed the toxicity of vanadium when used to reduce blood glucose levels. Administration of the
various combinations of the antidiabetic compounds to diabetic animals was found to reverse most of the diabetic effects studied
at physiological, biochemical, histochemical and molecular levels. Results of the key enzymes of metabolic pathways have been
summarized together with glucose transporter, Glut-4 and insulin levels. Our findings illustrate and elucidate the antidiabetic/insulin
mimetic effects of Trigonella, manganese and vanadium. 相似文献
119.
Hydrogels formed from (meth)acrylated poly(ethylene glycol) precursors are commonly used in a variety of biomedical applications ranging from tissue engineering to biosensors. While this approach has proven quite diverse, a major limitation to this approach is the heterogeneities and nonidealities that arise in the gels from the chain polymerization process, which increases the difficulty in relating the network structure to the final physical properties of the gel. Here we have exploited the specificity and fidelity of the [3+2] cycloaddition reaction to synthesize hydrogels with controlled architectures and improved mechanical properties. Moreover, we demonstrate a general approach toward the integration of multifunctional photoreactive polypeptide sequences into the network structure that provides a facile way to independently tune the 3D chemical and physical properties of the gel. Standard photolithographic techniques were used to generate a variety of two- and three-dimensional patterns as well as controlled biochemical gradients within existing preformed hydrogels. 相似文献
120.
Patterns of differentiation and hybridization in North American wolflike canids, revealed by analysis of microsatellite loci 总被引:8,自引:0,他引:8
Roy MS; Geffen E; Smith D; Ostrander EA; Wayne RK 《Molecular biology and evolution》1994,11(4):553-570
Genetic divergence and gene flow among closely related populations are
difficult to measure because mutation rates of most nuclear loci are so low
that new mutations have not had sufficient time to appear and become fixed.
Microsatellite loci are repeat arrays of simple sequences that have high
mutation rates and are abundant in the eukaryotic genome. Large population
samples can be screened for variation by using the polymerase chain
reaction and polyacrylamide gel electrophoresis to separate alleles. We
analyzed 10 microsatellite loci to quantify genetic differentiation and
hybridization in three species of North American wolflike canids. We
expected to find a pattern of genetic differentiation by distance to exist
among wolflike canid populations, because of the finite dispersal distances
of individuals. Moreover, we predicted that, because wolflike canids are
highly mobile, hybrid zones may be more extensive and show substantial
changes in allele frequency, relative to nonhybridizing populations. We
demonstrate that wolves and coyotes do not show a pattern of genetic
differentiation by distance. Genetic subdivision in coyotes, as measured by
theta and Gst, is not significantly different from zero, reflecting
persistent gene flow among newly established populations. However, gray
wolves show significant subdivision that may be either due to drift in past
Ice Age refugia populations or a result of other causes. Finally, in areas
where gray wolves and coyotes hybridize, allele frequencies of gray wolves
are affected, but those of coyotes are not. Past hybridization between the
two species in the south-central United States may account for the origin
of the red wolf.
相似文献