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41.
Mark van den Boogaard Rachel PL van Swelm Frans GM Russel Suzanne Heemskerk Johannes G van der Hoeven Rosalinde Masereeuw Peter Pickkers 《Proteome science》2011,9(1):13
Background
Suitable biomarkers associated with the development of delirium are still not known. Urinary proteomics has successfully been applied to identify novel biomarkers associated with various disease states, but its value has not been investigated in delirium patients. 相似文献42.
G Abu Sheika E Tramontano A G Loi P Franchetti M Grifantini P La Colla 《Nucleosides & nucleotides》1999,18(4-5):849-851
Integrase (IN) is an essential enzyme in the human immunodeficiency virus type-1 (HIV-1) replication cycle and, thus, a potential target for chemotherapeutic agents. Because various nucleotide analogues have been reported to inhibit IN in vitro, we investigated the effect of acyclic nucleoside phosphonates. Both unphosphorylated and diphosphorylated derivatives were inhibitory to IN at concentrations ranging between 60 and 800 microM, with diphosphorylated derivatives being 5- to 8-fold more potent than unphosphorylated counterparts. 相似文献
43.
Recombinant DNA methods have been exploited to enable the creation of protein-based block copolymers with programmable sequences, desired properties, and predictable three-dimensional structures. These advantages over conventional polymer counterparts facilitate the utility of this new class of biomaterials in a wide range of applications. In this project, we exploited the environmental application of protein-based block copolymers based on elastin-like protein (ELP) sequences. Triblock copolymers containing charged and hydrophobic segments were synthesized. Chain lengths of each segment were manipulated in order to maintain a gelation point below room temperature. Polyhistidine sequences were successfully incorporated into the hydrophilic segment without disruption of the self-assembled hydrogel formation. The microscopic structure was further investigated using laser confocal microscopy. The metal binding capability and capacity of resulting hydrogel were studied to demonstrate the functionality of polyhistidine and its environmental application for heavy metal removal. Reversibility of metal binding was demonstrated, indicating the cost-effectiveness of this hydrogel. Significantly, we envision that this versatile strategy of incorporating functional groups within a 3-D protein network provides new possibilities in creation of biomaterials with great control over structure-property relationships. 相似文献
44.
FMRFamide-related peptides (FaRPs) are among several neurotransmitters known to regulate the chromatophore function in the European cuttlefish Sepia officinalis. Here we report the cloning and sequencing of a novel S. officinalis FaRP gene (SOFaRP(2)). The complete 835-base pair cDNA sequence of the SOFaRP(2) gene contains an open reading frame of 567 base pairs encoding 188 amino acids and four putative FaRPs, NSLFRFamide, GNLFRFamide, TIFRFamide and PHTPFRFamide. All except TIFRFamide cause chromatophore expansion when assayed in an in vitro chromatophore bioassay. To investigate the expression pattern of SOFaRP(2) gene in the cuttlefish brain, in situ hybridization was performed using a full length RNA probe. The SOFaRP(2) gene was expressed primarily in the posterior chromatophore, anterior chromatophore, lateral basal and optic lobes among other brain locations. The SOFaRP(2) gene appears to be expressed in all brain regions involved in chromatophore regulation. These data suggests that some or all of the four FaRPs encoded by SOFaRP(2) might be involved in controlling chromatophore activity in cuttlefish. 相似文献
45.
Mario PL Calus Theo HE Meuwissen Jack J Windig Egbert F Knol Chris Schrooten Addie LJ Vereijken Roel F Veerkamp 《遗传、选种与进化》2009,41(1):11
The aim of this paper was to compare the effect of haplotype definition on the precision of QTL-mapping and on the accuracy of predicted genomic breeding values. In a multiple QTL model using identity-by-descent (IBD) probabilities between haplotypes, various haplotype definitions were tested i.e. including 2, 6, 12 or 20 marker alleles and clustering base haplotypes related with an IBD probability of > 0.55, 0.75 or 0.95. Simulated data contained 1100 animals with known genotypes and phenotypes and 1000 animals with known genotypes and unknown phenotypes. Genomes comprising 3 Morgan were simulated and contained 74 polymorphic QTL and 383 polymorphic SNP markers with an average r2 value of 0.14 between adjacent markers. The total number of haplotypes decreased up to 50% when the window size was increased from two to 20 markers and decreased by at least 50% when haplotypes related with an IBD probability of > 0.55 instead of > 0.95 were clustered. An intermediate window size led to more precise QTL mapping. Window size and clustering had a limited effect on the accuracy of predicted total breeding values, ranging from 0.79 to 0.81. Our conclusion is that different optimal window sizes should be used in QTL-mapping versus genome-wide breeding value prediction. 相似文献
46.
B. Pérez-Ortega H. Fernández-Marín M. S. Loiácono P. Galgani W. T. Wcislo 《Insectes Sociaux》2010,57(3):317-322
A number of wasps in the family Diapriidae, subfamily Diapriinae (Proctotrupoidea), are parasitoids that specialize on ant
larvae. These wasps are abundant and diverse in the Neotropics, but little is known about their biology. We studied parasitism
rates by an array of diapriine wasps that attack the larvae of fungus-growing ants, Trachymyrmex cf. zeteki, in a single population (near Gamboa, Panamá). Relatively little is known about the biology and natural history of these ants,
so we also present data on colony size and nest architecture. We excavated 136 colonies in central Panamá from June to September
2006, and 20 nests from July 2009. We reared six wasp morphotypes; two of them in the genus Mimopriella Masner and Garcia, one Oxypria Kieffer, two Szelenyiopria Fabritius and one Acanthopria Ashmead. The mean intensity of larval parasitism per ant colony was 33.9% (2006), and its prevalence across all ant populations
was 27.2% (2006 and 2009). Parasitism rates were not positively correlated with host colony size. A single case of super-parasitism
was documented in which two Oxypria males were reared from the same host larva. 相似文献
47.
The endothelin B receptor (ETB) is an endothelial cell receptor found in caveolae. Studies with GFP-tagged ETB have suggested that the protein is constitutively endocytosed and targeted to lysosomes where it is rapidly degraded. We report that iodinated endothelin-1 ligand (ET-1) is taken up by cells transfected with ETB and remains undegraded for at least 17 h. Analysis of the intracellular traffic of endocytosed ET-1 on isotonic Ficoll gradients shows that it is rapidly internalised to lysosomes by a chloroquine sensitive and cholesterol dependent pathway. Low-temperature nonreducing SDS gels show that the ET-1 initially binds to full-length GFP-tagged ETB, which is rapidly clipped at the amino-terminus and is then stable for at least 6 h. Analysis of GFP tagged ETB on reducing SDS gels shows that it is proteolytically cleaved with a half time of approximately 3 h. However, nonreducing gels show that the receptor is virtually intact, suffering only a similar cleavage to the liganded receptor. We conclude that the ETB receptor shows remarkable stability in lysosomes, held together by disulfide bonds, and maintaining ligand binding for long periods of time. 相似文献
48.
Griffon JF Dukhan D Pierra C Benzaria S Loi AG La Colla P Sommadossi JP Gosselin G 《Nucleosides, nucleotides & nucleic acids》2003,22(5-8):707-709
In order to evaluate their antiviral properties, a series of 4'-C-methyl-beta-D-ribofuranosyl purine and pyrimidine nucleosides has been prepared. Unfortunately, none of these 4'-branched nucleosides showed any antiviral activity or cytotoxcity when tested against HIV, HBV, and Yellow Fever virus. 相似文献
49.
Genomic imprinting in ruminants: allele-specific gene expression in parthenogenetic sheep 总被引:5,自引:0,他引:5
Studies in the mouse have established that both parental genomes are essential for normal embryonic development. Parthenogenetic
mouse embryos (which have two maternal genomes and no paternal genome), for example, are growth-retarded and die at early
postimplantation stages. The distinct maternal and paternal contributions are mediated by genomic imprinting, an epigenetic
mechanism by which the expression of certain genes is dependent on whether they are inherited from mother or father. Although
comparative studies have established that many imprinted mouse (and rat) genes are allele-specifically expressed in humans
as well (and vice versa), so far imprinting studies have not been performed in other mammalian species. When considering evolutionary
theories of genomic imprinting, it would be important to know how widely it is conserved among placental mammals. We have
investigated its conservation in a bovid ruminant, the domestic sheep, by comparing parthenogenetic and normal control embryos.
Our study establishes that, like in the mouse, parthenogenetic development in sheep is associated with growth-retardation
and does not proceed beyond early fetal stages. These developmental abnormalities are most likely caused by imprinted genes.
We demonstrate that, indeed, like in mice and humans, the growth-related PEG1/MEST and Insulin-like Growth Factor 2 (IGF2) genes are expressed from the paternal chromosome in sheep. These observations suggest that genomic imprinting is conserved
in a third, evolutionarily rather diverged group of placental mammals, the ruminants.
Received: 13 May 1998 / Accepted: 16 July 1998 相似文献
50.
Micromanipulation techniques are widely used in assisted human reproduction and it is logical to assume that successes with recent animal cloning will invariably raise the question of human cloning along with its related ethical problems. However, it is often overlooked that even in animals many complications are still associated with this technique. The purpose of our article is to highlight and discuss some of these problems in the context of the eventual use of nuclear and/or cytoplasmic transfer techniques in assisted human reproduction. 相似文献