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981.
V. G. Nicoletti E. A. Tendi C. Lalicata S. Reale A. Costa R. F. Villa N. Ragusa Prof. A. M. Giuffrida Stella 《Neurochemical research》1995,20(12):1465-1470
The contents of subunits I, II/III, and IV of cytochrome c oxidase and of subunits , and of FoF1 ATP synthase in inner mitochondrial membrane proteins purified from cerebral cortex of rat at 2, 6, 12, 18, 24, and 26 months of age were analyzed by western blot. Age-related changes in the content of subunits, either of mitochondrial or nuclear origin, were observed. All the cytochrome c oxidase (COX) subunits examined showed an age-related increase from 2-month-old rats up to 24 months with a decrease at the oldest age (26 months). The same pattern of age-dependent changes was observed for ATP synthase, while the and subunits increased progressively up to 26 months. 相似文献
982.
Dr F Marinelli S Stella N Montanini F Le Monnier L Cavaletti E Selva 《Journal of industrial microbiology & biotechnology》1995,15(1):49-54
Streptomyces sp GE44282 was isolated in the course of a screening program for novel antibiotics. It co-produces heneicomycin and aurodox, two kirromycin-type antibiotics, which differ by the presence of an hydroxyl group at the C30 position of aurodox. Heneicomycin is converted into aurodox both by growing and resting cells ofStreptomyces sp GE44282 and by the producer of aurodox,Streptomyces goldiniensis ATCC 21386. This bioconversion of heneicomycin is substrate-specific and is not observed using the producer of heneicomycin,Streptomyces filippiniensis NRRL 11044. The three strains show very similar taxonomic characteristics. These results suggest that heneicomycin is a precursor of aurodox, the production of which depends on the bioconversion capability expressed by the strain. 相似文献
983.
Induction of Primary Response Genes by Excitatory Amino Acid Receptor Agonists in Primary Astroglial Cultures 总被引:6,自引:1,他引:5
984.
Granulocytes differ from other blood cells in that they are more sensitive to injury on freezing and thawing. Previous studies suggest that the difficulty in preserving them is related to their sensitivity to osmotic stress. A miniaturized system both for freezing granulocytes and testing their function in the same Terasaki plates has been developed. This allowed study of several factors simultaneously including concentration of protective additive, different cooling conditions, and dilution conditions on rewarming.We observed two types of injury to granulocytes frozen to higher subzero temperatures and thawed directly. The first type was initially severe but decreased with time in the frozen state under some conditions and appears not to have been reported in other cell systems. The second type of injury consists of conventional loss of function with longer holding times after freezing. Cells surviving these two classes of injury could be protected against the further stress of rapid cooling into liquid nitrogen, but this protection required a longer time during cooling in the frozen state than with other cell types.We have studied the interactions between several variables, e.g., time in DMSO before freezing and dilution rate after thawing in an attempt to characterize the unusual injurious mechanism at high subzero temperatures that, we believe, is the real cause of the difficulty of preserving these cells. 相似文献
985.
Optimal conditions for the preservation of mouse lymph node cells in liquid nitrogen using cooling rate techniques 总被引:1,自引:0,他引:1
The factors that affect the survival of mouse lymphocytes throughout a procedure for storage at ?196 °C have been studied both for the improvement of recovery and the possible extension to the mouse system of cell selection by freezing. After thawing, the survival of cells cooled at different rates in dimethyl sulphoxide (DMSO, 5 or 10%, ) was assessed from the [3H]thymidine incorporation in response to phytohaemagglutinin and concanavalin A. Before freezing the protection against freezing damage increased with time (up to 20 min) in DMSO (5%, ) at 0 °C. Superimposed upon this effect was toxicity due to the DMSO. During freezing and thawing the cooling rate giving optimal survival was 8 to 15 °C/min for cells in DMSO (5%) and 1 to 3 °C/min for DMSO (10%). Omission of foetal calf serum was detrimental. Rapid thawing (>2.5 °C/min) was superior to slow thawing. After thawing dilution at 25 or 37 °C greatly improved cell survival compared with 0 °C; at 25 °C survival was optimal (75%) at a moderate dilution rate of 2.5 min for a 10-fold dilution in FCS (10%, ) followed by gentle centrifugation (50g).Dilution damage during both thawing and post-thaw dilution may be due to osmotic swelling as DMSO and normally excluded solutes leave the cell. The susceptibility of the cell membrane to dilution damage may also be increased during freezing. The need to thaw rapidly and dilute at 25 °C after thawing is probably due to a decrease in dilution stress at higher temperatures. Optimisation of dilution procedures both maximised recovery and also widened the range of cooling rates over which the cells were recovered. These conditions increase the possibility of obtaining good recovery of a mixed cell population using a single cooling procedure. Alternatively, if cell types have different optimal cooling rates, stressful dilution may allow their selection from mixed cell populations. 相似文献
986.
G Ramieri M Stella M Calcagni S Teich-Alasia G Cellino G C Panzica 《Acta anatomica》1992,144(4):343-347
The present study elucidates the morphology of encapsulated receptors in human skin by means of immunohistochemistry for the recently characterized neurospecific marker protein gene product 9.5, in comparison with neuronal specific enolase and S-100 protein. Only two types of corpuscles are identified, Meissner's corpuscles and simple coiled corpuscles. Moreover, this investigation reveals that though regional specialization may exist with regard to the encapsulated receptor density, the comparison of hairy and nonhairy skin does not reveal important differences. 相似文献
987.
Temporal analysis of brown eye spot of coffee and its response to the interaction of irrigation with phosphorous levels 下载免费PDF全文
Eugênio Chaves Edson Ampélio Pozza Helon Santos Neto Gabriel Brandão Vasco Gabriel Avelar Dornelas Adélia Aziz Alexandre Pozza Myriane Stella Scalco 《Journal of Phytopathology》2018,166(9):613-622
Brown eye spot (BES—Cercospora coffeicola) is a major disease of coffee, and its occurrence is affected by water supply and nutritional balance. Little is known about the effect of phosphorous (P) on coffee fields under irrigation. Thus, this study evaluated the effect of the interaction between different water application levels and phosphorus levels (5 irrigation levels × 4 phosphorus levels) on the intensity of this disease. The area under the incidence progress curve (AUIPC) was calculated and subjected to analysis of variance. The progress curve of the average incidence of BES varied in both evaluation years. In Year 1 (November 2011 to December 2012), the incidence peaked on August 12, 2012 (22.45%), while in Year 2 (January 2013 to January 2014), the incidence reached its highest level on September 12, 2013 (16.29%). The exponential nonlinear model was adjusted for the two years. There was an interaction between irrigation and phosphorus levels on October 07, 2012. The incidence interacted significantly with the harvest dates. On the first evaluation date, an increase in phosphorus levels at shallower irrigation depths and an absence of phosphate fertilizer at higher irrigation levels caused higher incidences. 相似文献
988.
Jonathan Auerbach Richard Howey Lai Jiang Anne Justice Liming Li Karim Oualkacha Sergi Sayols-Baixeras Stella W. Aslibekyan 《BMC genetics》2018,19(1):74
Background
Increasingly available multilayered omics data on large populations has opened exciting analytic opportunities and posed unique challenges to robust estimation of causal effects in the setting of complex disease phenotypes. The GAW20 Causal Modeling Working Group has applied complementary approaches (eg, Mendelian randomization, structural equations modeling, Bayesian networks) to discover novel causal effects of genomic and epigenomic variation on lipid phenotypes, as well as to validate prior findings from observational studies.Results
Two Mendelian randomization studies have applied novel approaches to instrumental variable selection in methylation data, identifying bidirectional causal effects of CPT1A and triglycerides, as well as of RNMT and C6orf42, on high-density lipoprotein cholesterol response to fenofibrate. The CPT1A finding also emerged in a Bayesian network study. The Mendelian randomization studies have implemented both existing and novel steps to account for pleiotropic effects, which were independently detected in the GAW20 data via a structural equation modeling approach. Two studies estimated indirect effects of genomic variation (via DNA methylation and/or correlated phenotypes) on lipid outcomes of interest. Finally, a novel weighted R2 measure was proposed to complement other causal inference efforts by controlling for the influence of outlying observations.Conclusions
The GAW20 contributions illustrate the diversity of possible approaches to causal inference in the multi-omic context, highlighting the promises and assumptions of each method and the benefits of integrating both across methods and across omics layers for the most robust and comprehensive insights into disease processes.989.
990.
Chronotropic responses to symphathomimetic amines of isolated atrial preparations from toads () were mediated by β-adrenoceptors since isoprenaline was more potent than adrenaline and noradrenaline, and propranolol was a potent antagonist (pA2, adrenaline as agonist = 9.33). The β-adrenoceptors had some of the characteristics of mammalian β2-adrenoceptors in that (i) adrenaline was more potent than noradrenaline and (ii) the pA2 values of two selective β-adrenoceptor antagonists, atenolol (pA2 = 5.84) and α-methylpropranolol (pA2 = 8.42), were close to the values reported on β2-adrenoceptors in mammalian tissues. However, the relative potencies of adrenaline, isoprenaline, noradrenaline, rimiterol, salbutamol and fenoterol (1 : 45.8 : 0.07 : 3.3 : 1.05 : 0.32) did not correspond to the relative potencies reported for these agonist on mammalian tissues which contain predominantly β2-adrenoceptors. Also the pA2 value for the β2-selective antagonist, ICI 118,551 (7.89, adrenaline as agonist) was lower than its reported pA2 on β2-adrenoceptors in mammalian tissues. There was no evidence that the response was mediated by both β1-andβ2-adrenoceptors since Schild plots for ICI 118,551 using three agonists of differing selectivity (adrenaline, rimiterol and noradrenaline) weer superimposed. It is concluded that, although toad atrial β-adrenoceptors have several characteristics in common with β2-adrenoceptors in mammalian tissues, these amphibian β-adrenoceptors are not identical with mammalian β2-adrenoceptors. 相似文献