876 resultados para Future in common


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The glutathione S-transferases play important roles in the detoxification of microcystin. In this experiment, nine glutathione S-transferase genes including cytosolic GSTs (rho, mu, theta, alpha and pi), mitochondrial GST (kappa) and microsomal GSTs (mGST1, mGST2 and mGST3) were cloned from common carp Cyprinus carpio. The mRNA abundance of each carp GST isoform in liver was analyzed by real time PCR. The relative changes after stimulation with microcystin LR were also analyzed: increased levels of transcription of GST alpha, rho and mGST3 isoforms were detected at 6 h post stimulation; the transcription of mu, theta and mGST2 isoforms were relatively stable; and all the GST isoforms except GST kappa and rho recovered to original levels compared with controls at 72 h. It is suggested that MC-LR showed different effects on the transcription of nine carp GST isoforms. (c) 2006 Elsevier B.V. All rights reserved.

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Gonadotropin-releasing hormone (GnRH) is a conservative neurodecapeptide family, which plays a crucial role in regulating the gonad development and in controlling the final sexual maturation in vertebrate. Two differing cGnRH-II cDNAs of common carp, namely cGnRH-II cDNA1 and cDNA2, were firstly cloned from the brain by rapid amplification of cDNA end (RACE) and reverse transcription- polymerase chain reaction (RT-PCR). The length of cGnRH-II cDNA1 and cDNA2 was 622 and 578 base pairs (bp), respectively. The cGnRH-II precursors encoded by two cDNAs consisted of 86 amino acids, including a signal peptide, cGnRH-II decapeptide and a GnRH-associated peptide (GAP) linked by a Gly-Lys-Arg proteolytic site. The results of intron trapping and Southern blot showed that two differing cGnRH-II genes in common carp genome were further identified, and that two genes might exist as a single copy. The multi-gene coding of common carp cGnRH-II gene offered novel evidence for gene duplication hypothesis. Using semi-quantitative RT-PCR, expression and relative expression levels of cGnRH-II genes were detected in five dissected brain regions, pituitary and gonad of common carp. With the exception of no mRNA2 in ovary, two cGnRH-II genes could be expressed in all the detected tissues. However, expression levels showed an apparent difference in different brain regions, pituitary and gonad. According to the expression characterization of cGnRH-II genes in brain areas, it was presumed that cGnRH-II might mainly work as the neurotransmitter and neuromodulator and also operate in the regulation for the GnRH releasing. Then, the expression of cGnRH-II genes in pituitary and gonad suggested that cGnRH-II might act as the autocrine or paracrine regulator.

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The first successful case of transgenic fish was achieved in 1984. It is in a model system that the integration and expression of recombinant human growth hormone (hGH) in host red common carp (Cyprinus carpio, red var.) have been thoroughly studied. Recently, the integration sites have been recovered and characterized. Compared with non-transgenic peers, hGH-transgenic fish are prior in dietary utilization and growth performance. In view of bio-safety and bio-ethics, an "all-fish" construct CAgcGH, grass carp growth hormone fused with common carp P-actin promoter, has been generated and transferred into Yellow River carp (C carpio, local strain in Yellow River) fertilized eggs. Under middle-scale trial, CAgcGH-transgenics show higher growth rate and food conversion efficiency than the controls, which is consistent to laboratory findings. To avoid the potential impact of transgenic fish on the environment, a sterile strain of transgenic triploid fish has been successfully produced. The "all-fish" transgenic common carp is also approved safe enough as daily food, according to a test based on the pathological principles of new medicines issued by the Ministry of Health of China. The "all-fish" transgenic common carp with growth enhancement is now ready for market, but looking for governmental authorization. (C) 2003 Editions scientifiques et medicales Elsevier SAS and Ifremer/IRD/Inra/Cemagref. All rights reserved.

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The transgenic carp were produced by micro-injection of CAgcGHc into the fertilized eggs. Observation of the thymus development between the transgenics and non-transgenic controls was carried out. The thymus of one-year-old transgenics F1 showed a great increase in both size and weight. The unilateral thymus of the transgenics weighed from 190 to 295 mg with average 218.6 mg, whereas the unilateral thymus of the controls weighed 20-81 mg with average 42.5 mg; i.e. the thymus weight in the transgenics was 5.14 fold over that in the controls. The index of thymus/body weight in the transgenics was 2.97 fold over the controls. Light microscopy observation indicated that the thymus of the transgenics; well developed with the thickened outer region and compactly arranged thymocytes, while the thymus in the controls were degenerating with the thinned outer region, scattered thymocytes and groups of fatty cells. Further analysis with the electron microscopy revealed that pro-liferous cells in the transgenics; were mainly small lymphocytes and no pathological changes were found. The results confirmed that the "All-fish" GH-transgene promotes thymus development and thymocyte proliferation, and retards thymus degeneration. The study has laid a foundation for further analysis of the immunobiological function in GH-transgenic carp.

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A study was undertaken on the susceptibility of the F-4 generation of "all-fish" growth hormone transgenic carp, Cyprinus carpio L, against Ichthyophthirius multifiliis infections. When 1-year old, transgenic carp, with non-transgenic carp and non-manipulated carp (controls) were split into three batches, and experimental infections were performed throughout the 3-month period. All 72 fish were successfully infected. It was shown that there was a significant difference (P<0.01) on infection level between transgenics and non-transgenics, and transgenics and controls. It possibly resulted from transgenics that had stronger non-specific immune functions. In addition, fish surface area affected significantly infection level (P<0.001). Carp with larger surface area harboured more parasites for each type of fish, but transgenic with larger surface area than non-transgenics and controls (P<0.01), loaded fewer parasites than others. Besides, the time of infection also greatly influenced (P<0.001) infection level. Results showed that there was a significant decline in parasite infectivity through October to November (P<0.001). It was likely to suggest that there existed senescence resulted in failure of any I. multifiliis isolate maintenance. Significant difference in infectivity between isolate G from grass carp and isolate H from gold fish suggested that different parasite strains may exist. (C) 2009 Elsevier B.V. All rights reserved.

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Priest, A. (2005). In Common Cause: The NATO Multilateral Force and Mixed-Manning Demonstration on USS Claude V. Ricketts, 1964-1965. Journal of Military History, 69 (3), 759-789. RAE2008

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We compared non-shivering thermogenesis between two adjacent populations of freshly captured common spiny mice (Acomys cahirinus) during both winter and summer. Mice were captured from north- and south-facing slopes (NFS and SFS) of the same valley that represent 'Mediterranean' and 'Desert' habitats, respectively. Oxygen consumption and body temperature responses to an injection of exogenous noradrenaline (NA) were higher during the winter than during the summer. in addition, SFS mice had a lower body temperature response to NA during the summer than the other groups of mice. This suggests that heat dissipation is likely to have been greatest in SFS mice during the summer. Overall this study shows that seasonal acclimatization of NST mechanisms is an important trait for small mammals that inhabit the Mediterranean ecosystem. Differences in physiological capabilities can occur temporally within populations across seasons, and spatially between populations that are only a short distance (200-500 m) apart.

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1. We compared resting metabolic rate (RMR) and non-shivering thermogenesis (NST) values between founder and F1-populations of winter-acclimatized Acomys cahirinus that originated from north- and south-facing slopes (NFS and SFS) of the same valley, representing mesic and xeric habitats. 2. NST was measured by the increase in oxygen consumption (VO2) and body temperature (T-b) after a noradrenaline (NA) injection (VO2 NA, TbNA). 3. Body mass and TbNA values were higher in SFS F1-mice, while RMR and VO2 NA values were higher in NFS F1-mice. Differences were not apparent in founders. 4. Results are consistent with NFS and SFS mice being considered as

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WaaL is a membrane enzyme that catalyzes a key step in lipopolysaccharide (LPS) synthesis: the glycosidic bonding of a sugar at the proximal end of the undecaprenyl-diphosphate (Und-PP) O-antigen with a terminal sugar of the lipid A-core oligosaccharide (OS). Utilizing an in vitro assay, we demonstrate here that ligation with purified Escherichia coli WaaL occurs without adenosine-5'-triphosphate (ATP) and magnesium ions. Furthermore, E. coli and Pseudomonas aeruginosa WaaL proteins cannot catalyze ATP hydrolysis in vitro. We also show that a lysine substitution of the arginine (Arg)-215 residue renders an active protein, whereas WaaL mutants with alanine replacements in the periplasmic-exposed residues Arg-215, Arg-288 and histidine (His)-338 and also the membrane-embedded aspartic acid-389 are nonfunctional. An in silico approach, combining predicted topological information with the analysis of sequence conservation, confirms the importance of a positive charge at the small periplasmic loop of WaaL, since an Arg corresponding to Arg-215 was found at a similar position in all the WaaL homologs. Also, a universally conserved H[NSQ]X(9)GXX[GTY] motif spanning the C-terminal end of the predicted large periplasmic loop and the membrane boundary of the transmembrane helix was identified. The His residue in this motif corresponds to His-338. A survey of LPS structures in which the linkage between O-antigen and lipid A-core OS was elucidated reveals that it is always in the beta-configuration, whereas the sugars bound to Und-PP are in the alpha-configuration. Together, our biochemical and in silico data argue that WaaL proteins use a common reaction mechanism and share features of metal ion-independent inverting glycosyltransferases.

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We study the exact entanglement dynamics of two qubits in a common structured reservoir. We demonstrate that for certain classes of entangled states, entanglement sudden death occurs, while for certain initially factorized states, entanglement sudden birth takes place. The backaction of the non-Markovian reservoir is responsible for revivals of entanglement after sudden death has occurred, and also for periods of disentanglement following entanglement sudden birth.

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Common variable immunodeficiency (CVID) is a primary immunodeficiency characterized by hypogammaglobulinaemia and antibody deficiency to both T dependent and independent antigens. Patients suffer from recurrent sinopulmonary infections mostly caused by Streptococcus pneumoniae and Haemophilus influenzae, but also gastrointestinal or autoimmune symptoms. Their response to vaccination is poor or absent. In this study we investigated B cell activation induced by the TLR9 specific ligand (CpG-ODN) and bacterial extracts from S. pneumoniae and H. influenzae known to stimulate several TLR. We found that B cells from CVID patients express lower levels of CD86 after stimulation with CpG-ODN, S. pneumoniae and H. influenzae extracts in combination with anti-IgM antibody and also display a lower proliferative index when stimulated with bacterial extracts. Our results point to a broad TLR signalling defect in B lymphocytes from CVID patients that may be related to the hypogammaglobulinaemia and poor response to vaccination characteristic of these patients.

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Roche tomography is a powerful tool for imaging the surfaces of stars. We have applied it to two contrasting systems, a normal dwarf nova, RU Peg, and the peculiar intermediate polar AE Aqr. Despite these differences, the Roche tomograms of the cool stars in the two systems are remarkably similar. We compare them with tomograms of two other stars, and discuss the differences and similarities. The rotation speed may be critical in determining the surface appearance, and it is strongly recommended that a Roche tomogram be obtained for the bright CV SS Cygni, which would be the fastest-rotating secondary to be studied. In addition, V426 Oph should be re-observed.