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601.
García-Guerrero M Villarreal H Racotta IS 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2003,135(1):147-154
The influence of temperature on biochemical composition, survival and duration of development of Cherax quadricarinatus from egg extrusion to juvenile was analyzed. Berried females were individually subjected to each of 22, 25, 28 and 31 degrees C (n=5 per temperature). Egg samples were obtained every 3 days from egg extrusion to juvenile stage for biochemical analysis. Duration of development and survival decreased with increasing temperature. At 22 and 25 degrees C half of the initial lipid content was consumed during development. At 28 and 31 degrees C, 80% of the initial amount of lipids was consumed. For proteins, depletion rate was significantly lower at 25 degrees C (36% of the initial amount) than at 22, 28 and 31 degrees C (61-65% of the initial amount). For carbohydrates, a significant consumption was observed only at 22 degrees C. Total energy consumption was lower at 22 and 25 degrees C than at 28 and 31 degrees C. We conclude that 22-25 degrees C is the optimal temperature range for C. quadricarinatus egg incubation, although 25 degrees C might be better in terms of development duration in terms of survival, energy cost and protein consumption. 相似文献
602.
Yolk proteins during ovary and egg development of mature female freshwater crayfish (Cherax quadricarinatus) 总被引:4,自引:0,他引:4
Serrano-Pinto V Vazquez-Boucard C Villarreal-Colmenares H 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2003,134(1):33-43
Vitellins from ovaries and eggs at different stages of development in freshwater crayfish (Cherax quadricarinatus) were examined by chromatography, PAGE and SDS-PAGE. With these methods, two forms of vitellin (Vt1 and Vt2) were observed in ovaries and eggs (stages I and V). In ovaries in secondary vitellogenesis, native molecular mass was 470 (Vt1) and 440 (Vt2) kDa. The electrophoretic pattern of the eggs proved to be more complex. The protein molecular mass depend on the development stage of the egg: stage I, 650 kDa (Vt1) and 440 kDa (Vt2); stage V, 390 kDa (Vt1) and 340 kDa (Vt2). The identified vitellins appear to be lipo-glycocarotenoprotein. A similar vitellin polypeptide composition was observed in the two forms of vitellin from ovaries and eggs in stage V. In ovaries the SDS-PAGE analysis showed four subunits with molecular weights of approximately 180, 120, 95 and 80 kDa (Vt1 and Vt2). The polypeptide composition in the two forms of vitellins in stage I and stage III eggs were different at 195, 190, 130 and 110 kDa (Vt1) and 116 and 107 kDa (Vt2). On the other hand, in stage V eggs, 110, 95, 87 and 75 kDa (Vt1 and Vt2) were identified. Two antibodies (Ab1 and Ab2) were prepared against the purified proteins of stage V eggs and their specificity was demonstrated by radial immunoprecipitation, and Western blotting analysis. Two forms of vitellins were also found in stage V eggs after chromatography on Sepharose CL-2B column and hydroxylapatite and polyacrylamide gel electrophoresis. 相似文献
603.
604.
Hernández-Hernández Fde L de Muñoz FG Rojas-Martínez A Hernández-Martínez S Lanz-Mendoza H 《Archives of insect biochemistry and physiology》2003,54(1):37-45
The activation of Dactylopius coccus (Costa) hemolymph with microbial polysaccharide molecules was studied. Hemolymph incubated in the presence of laminarin, zymosan, and N-acetyl glucosamine produced a dark fibrillar precipitated, and the red pigment (carminic acid) was consumed (measured spectrophotometrically at 495 nm). Lipopolysaccharide (LPS) did not induce any response. The reaction was inhibited with millimolar concentrations of serine and cysteine protease inhibitors, EGTA and phenyl thiourea. It was also diminished by prostaglandin synthesis inhibitors: dexamethasone, acetylsalicylic acid, and indomethacin. However, Mg2+ chelator EDTA did not inhibit hemolymph activation. Hemolymph proteins were depleted from soluble phase during treatment with laminarin, but a group of around 34 kDa remained unmodified. These results showed that D. coccus hemolymph is activated by microbial elicitors, its activation depends on eicosanoids, and suggest participation of a prophenoloxidase (PPO)-like activation system that could consume carminic acid. We are currently dissecting the molecular factors involved in D. coccus hemolymph activation to determine homologies and differences with other arthropods immune response pathways. 相似文献
605.
Design and synthesis of orally active inhibitors of TNF synthesis as anti-rheumatoid arthritis drugs
Chen JJ Dewdney N Lin X Martin RL Walker KA Huang J Chu F Eugui E Mirkovich A Kim Y Sarma K Arzeno H Van Wart HE 《Bioorganic & medicinal chemistry letters》2003,13(22):3951-3954
A novel series of TNF inhibitors was identified based on the screening of existing MMP inhibitor libraries. Further SAR optimization led to the discovery of a novel lead compound. Its synthesis, efficacy in experimental animal models, and pharmacokinetic data are discussed. 相似文献
606.
Xabier Murelaga France de Lapparent de Broin Jean-Claude RageSylvain Duffaud Humberto AstibiaAinara Badiola 《Geobios》2002,35(3):347
The Lower Miocene deposits of the Bardenas Reales of Navarre (NW Ebro Basin, northern Iberian Peninsula) have yielded a diverse vertebrate fauna, including remains of amphibians and reptiles. These remains occur in several localities in the Tudela Formation. The fossiliferous levels belong to the Biozones MN2b-3 (Biozones Z-A of the Ramblian, i.e., Late Aquitanian to Early Burdigalian in age). The amphibians and reptiles represent at least 13 out of 37 vertebrate species. Amphibians consist of a salamandrid urodele and two or three anurans. All the turtles are cryptodirans and consist of the chelydrid Chelydropsis apellanizi, the testudinids Ptychogaster (Temnoclemmys) bardenensis and Ptychogaster ronheimensis, and a Trionychinae indet. Squamates are represented by the anguid lizard Ophisaurus sp., a non-anguid lacertilian, an amphisbaenian, the erycine boid? Eryx sp., and indeterminate colubrids. Crocodilian remains are assigned to the basal alligatoroid Diplocynodon sp. The fossil associations of the Bardenas Reales of Navarre suggest that the vertebrates lived in the centre of an endoreic basin with stretches of water under intertropical to subtropical climatic conditions. 相似文献
607.
In this study we investigated the population genetic structure of the queenless ant Diacamma cyaneiventre. This species, lacking winged queens, is likely to have a restricted female dispersal. We used both mitochondrial and microsatellite markers to assess the consequence of such restricted female dispersal at three geographical scales: within a given locality (< 1 km), between localities within a given region (< 10 km) and between regions (> 36 km). Within a locality, a strong population structure was observed for mitochondrial DNA (mtDNA) whereas weak or nonexistent population genetic structure was observed for the microsatellites (around 5% of the value for mtDNA). Male gene flow was estimated to be about 20-30 times higher than female gene flow at this scale. At a larger spatial scale, very strong genetic differentiation for both markers was observed between localities - even within a single region. Female dispersal is nonexistent at these scales and male dispersal is very restricted, especially between regions. The phylogeographical structure of the mtDNA haplotypes as well as the very low genetic diversity of mtDNA within localities indicate that new sites are colonized by a single migration event from adjacent localities, followed by successive colony fissions. These patterns of genetic variability and differentiation agree with what is theoretically expected when colonization events are kin-structured and when, following colonization, dispersion is mainly performed by males. 相似文献
608.
García-Arellano H Valderrama B Saab-Rincón G Vazquez-Duhalt R 《Bioconjugate chemistry》2002,13(6):1336-1344
Chemically modified cytochrome c with poly(ethylene glycol) (PEG) showed activity at temperatures higher than 100 degrees C and to be highly thermostable. The molecular size of PEG moieties and the coupling site affected the thermal stabilization. An optimal PEG/protein mass ratio of 2.8 was found, producing a fully thermostable biocatalyst at 80 degrees C. Site-directed mutagenesis on yeast cytochrome c showed an increased thermostabilization when lysine 79 residue, localized at the edge of the active site, was replaced by a nonreactive residue. Tertiary, secondary, and active-site structures were analyzed by fluorescence, CD, and UV/visible spectroscopies. Besides its disordered structure, the pegylated protein showed a lower unfolding rate at the active-site than the unmodified ones. A shell-like structure seems to protect the heme environment, in which PEG is coiled on the protein surface with a primary shield of rigid water molecules solvating the hydrophilic region of bound-PEG, and the PEG hydrophobic regions interacting with the hydrophobic clusters on protein surface. 相似文献
609.
610.
Optimizing quantitative trait locus (QTL) mapping experiments requires a generalized measure of marker informativeness because variable information is obtained from different marker systems, marker distribution and pedigree types. Such a measure can be derived from the concept of Shannon entropy, a central concept in information theory. Here we introduce entropy-based founder informativeness (EFI), a new measure of information content generalized across pedigrees, maps, marker systems and mating configurations. We derived equations for inbred- and outbred-derived mapping populations. Mathematical properties of EFI include enhanced sensitivity to mapping population type and extension to any number of founders. To illustrate the use of EFI, we compared experimental designs for QTL mapping for three examples: (i) different marker systems for an F2 pedigree, (ii) different marker densities and sampling sizes for a BC1 pedigree and (iii) a comparison of haplotypic versus zygotic analyses of an outbred pedigree. As an a priori generalized measure of information content, EFI does not require phenotypic data for optimizing experimental designs for QTL mapping. 相似文献