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1.
Veronique Blanchard Rita Raisman-Vozari Marc Savasta Etienne Hirsch France Javoy-Agid Claude Feuerstein Yves Agid 《Journal of neurochemistry》1993,61(2):617-626
Abstract: We developed a rapid and sensitive radioimmunohistochemical method for the quantification of tyrosine hydroxylase (TH) at both the anatomical and cellular level. Coronal tissue sections from fresh-frozen rat brains were incubated in the presence of a TH monoclonal antibody. The reaction was revealed with a 35 S-labeled secondary antibody. TH content was quantified in catecholaminergic brain areas by measuring optical density on autoradiographic films or silver grain density on autoradiographic emulsion-coated sections. Regional TH concentrations determined in the locus ceruleus (LC), substantia nigra pars compacta (SNC), and ventral tegmental area (VTA) were significantly increased by 45% after reserpine treatment in the LC but unchanged in the SNC and VTA. Microscopic examination of TH radioimmunolabeling showed a heavy accumulation of silver grains over catecholaminergic cell bodies. In the LC, grain density per cell was heterogeneous and higher in the ventral than in the dorsal part of the structure. After reserpine treatment, TH levels were significantly increased (57%) in the neurons of the LC but not in those of the SNC or VTA. The data support the validity of this radioimmunohistochemical method as a tool for quantifying TH protein at the cellular level and they confirm that TH protein content is differentially regulated in noradrenergic and dopaminergic neurons in response to reserpine. 相似文献
2.
Etienne H.; Lartaud M.; Carron M.P.; Michaux-Ferrire N. 《Journal of experimental botany》1997,48(1):129-137
In Hevea brasiliensis (Mll. Arg.), increasing the calcium contentof the friable callus maintenance medium from 3 to 9 mM stimulatedregeneration potential through somatic embryogenesis. This stimulationcould be attributed to the homogeneous cytological structureof calluses, which were formed of undifferentiated cells capableof somatic embryogenesis in optimal culture conditions. Thevery marked increase in the active cell population was sufficientto cause a decrease and a stabilization of water and osmoticpotentials of the calluses, whereas their water content increased.The regeneration capacity of calluses cultured on a medium withadditional CaCl2 was greater in terms of both quantity (numberof somatic embryos produced was increased 2-fold) and quality(germination efficiency trebled). High CaCl2 concentrations (9 mM CaCl2) in the embryogenesisinduction medium favoured somatic embryo development when calluseswere maintained 2 months on the same medium. In this case, additionof benzylaminopurine (BAP) and 3,4-dichlorophenoxy- acetic acid(3,4-D) increased the number of embryos produced (243 embryosg1 FW callus) and their germination capacity (27%). These culture conditions were used to determine the optimumembryogenesis induction period. The length of the period affectedboth the intensity of embryogenesis (maximum 5677 d)and somatic embryo quality (maximum 4970 d). The bestresults were obtained with a 70 d embryogenesis induction period,within which 355 embryos g1 FW callus were obtained,with 35% germination. Key words: Calcium, somatic embryogenesis, long-term culture, water status, histology 相似文献
3.
Willy J. Malaisse Kowluru Anjaneyulu Renu Anjaneyulu Etienne Couturier 《Molecular and cellular biochemistry》1980,30(2):67-70
Summary In an artificial system, the ionophore A23187, which transports Ca2+ but not Na+, is able to mediate the uphill translocation of Ca2+ from one aqueous medium to another across an organic immiscible phase, provided that a Na+, Li+ or H+ gradient is imposed on the system. Therefore, in the process known as Na-Ca countertransport, the downhill influx of Na+ may not be necessary for causing Ca2+ extrusion against its electrochemical gradient. 相似文献
4.
5.
J Etienne A Grüber J Polonovski 《Comptes rendus des séances de la Société de biologie et de ses filiales》1976,170(6):1159-1165
When partially purified platelet-rat lysate is injected in the rat aorta, transformation of prophospholipase into phospholipase is observed. Blood prophospholipases are activated almost entirely during about 15 minutes; aortic phospholipase are entirely activated for a longer time. 相似文献
6.
Mustapha Arkoun Laëtitia Jannin Philippe Laîné Philippe Etienne Céline Masclaux-Daubresse Sylvie Citerne Maria Garnica José-Maria Garcia-Mina Jean-Claude Yvin Alain Ourry 《Plant and Soil》2013,362(1-2):79-92
Background and aims
Urea is the major nitrogen (N) form supplied as fertilizer in agriculture. However, urease, a nickel-dependent enzyme, allows plants to use external or internally generated urea as a nitrogen source. Since a urease inhibitor is frequently applied in conjunction with urea fertilizer, the N-metabolism of plants may be affected. The aim of this study was to determine physiological and molecular effects of nickel deficiency and a urease inhibitor on urea uptake and assimilation in oilseed rape.Methods
Plants were grown on hydroponic solution with urea as the sole N source under three treatments: plants treated with nickel (+Ni) as a control, without nickel (?Ni) and with nickel and phenylphosphorodiamidate (+Ni+PPD). Urea transport and assimilation were investigated.Results
The results show that Ni-deficiency or PPD supply led to reduced growth and reduced 15N-uptake from urea. This effect was more pronounced in PPD-treated plants, which accumulated high amounts of urea and ammonium. Thus, Ni-deficiency or addition of PPD, limit the availability of N and decreased shoot and root amino acid content. The up-regulation of BnDUR3 in roots indicated that this gene is a component of the stress response to nitrogen-deficiency. A general decline of glutamine synthetase (GS) activity and activation of glutamate dehydrogenase (GDH) and increases in its expression level were observed in control plants. At the same time, in (?N) or (+Ni+PPD) treated plants, no increases in GS or GDH activities and expression level were found.Conclusions
Overall results showed that plants require Ni as a nutrient (while most widely used nutrient solutions are devoid of Ni), whether they are grown with or without a urea supply, and that urease inhibitors may have deleterious effects at least in hydroponic grown oilseed rape. 相似文献7.
A PCR-Based Method for Monitoring Legionella pneumophila in Water Samples Detects Viable but Noncultivable Legionellae That Can Recover Their Cultivability 下载免费PDF全文
8.
Quiniou N Richard S Mourot J Etienne M 《Animal : an international journal of animal bioscience》2008,2(11):1633-1644
Two trials were carried out to compare the effects of fat or starch inclusion in sow's diet on sow and litter performance. In each trial, sows were assigned to one of two treatments. In trial 1, the sows were fed diets containing either soybean oil (5%, treatment GL5) or cornstarch (11.3%, GL0) from day 35 of gestation to weaning. Daily net energy and nutrient allowance were equalised during gestation. In trial 2, the same treatments were applied only after farrowing (treatments L5 and L0, respectively). Within each trial, a batch of piglets was studied until slaughter. In trial 1, adipose cell development and total lipid content were determined on some pigs at weaning (n = 6/treatment) and at slaughter in dorsal subcutaneous adipose tissue (n = 13/group at least) and in muscle (n = 46/group at least). Piglets' birth weight was not affected by treatment in trial 1. Survival rates at birth and after 24 h of life were higher in treatment GL5 (4.0% v. 7.5% stillborn piglets in GL0 treatment, P < 0.05; 8.7% v. 12.6% of piglets alive at 24 h of age died in treatment GL0, P = 0.06). Subsequently, overall survival rate until weaning was higher in treatment GL5 (81.4% v. 75.7% of total born piglets, P = 0.03), but litter size at weaning was not significantly affected (11.3). Litter growth rate before weaning was increased when a fat-enriched diet was provided during gestation and lactation (+140 g/day per litter; P < 0.01) and to a lower extent when provided only after farrowing (+90 g/day; P < 0.05). Energy supply through fat did not decrease the mobilisation of the sow's body reserve and backfat thickness loss was even higher with treatment GL5 (P < 0.05). After weaning, pigs' average daily gain, feed : gain ratio and carcass lean content were not affected by the energy source supplied before and/or after farrowing. At weaning, the number of adipose cells in the dorsal subcutaneous adipose tissue and in the Longissimus dorsi muscle was higher in the GL5 pigs. Muscle lipid content at weaning did not differ between treatments, but it was higher at slaughter, around 110 kg, in the GL5 pigs (3.46% v. 2.58%, P < 0.001). 相似文献
9.
Activities of prevalent protein phosphatases decreased by nearly 95% and those of individual protein kinases were differentially reduced at low temperature. Inhibition of phosphatase activity at temperatures below 12°C resulted in marked hyperphosphorylation of a 58-kDa protein (PP58). The temperature threshold for hyperphosphorylation of PP58 coincided with the known threshold for cold-induced calcium influx. Since calcium influx is triggered by several environmental stresses, we propose that the observed direct effects of cold on the phosphorylation of specific proteins enable cells to couple a shared calcium signal to a cold-specific transduction pathway. 相似文献
10.
In vivo importance of homologous recombination DNA repair for mouse neural stem and progenitor cells
Rousseau L Etienne O Roque T Desmaze C Haton C Mouthon MA Bernardino-Sgherri J Essers J Kanaar R Boussin FD 《PloS one》2012,7(5):e37194
We characterized the in vivo importance of the homologous recombination factor RAD54 for the developing mouse brain cortex in normal conditions or after ionizing radiation exposure. Contrary to numerous homologous recombination genes, Rad54 disruption did not impact the cortical development without exogenous stress, but it dramatically enhanced the radiation sensitivity of neural stem and progenitor cells. This resulted in the death of all cells irradiated during S or G2, whereas the viability of cells irradiated in G1 or G0 was not affected by Rad54 disruption. Apoptosis occurred after long arrests at intra-S and G2/M checkpoints. This concerned every type of neural stem and progenitor cells, showing that the importance of Rad54 for radiation response was linked to the cell cycle phase at the time of irradiation and not to the differentiation state. In the developing brain, RAD54-dependent homologous recombination appeared absolutely required for the repair of damages induced by ionizing radiation during S and G2 phases, but not for the repair of endogenous damages in normal conditions. Altogether our data support the existence of RAD54-dependent and -independent homologous recombination pathways. 相似文献