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991.
992.
Vincenza Vona Vittoria Di Martino Rigano Sergio Esposito Petronia Carillo Simona Carfagna Carmelo Rigano 《Physiologia plantarum》1999,105(2):288-293
N-sufficient cells of Chlorella sorokiniana Shihira and Krauss, strain 211/8k, absorbed NH4 + under light plus CO2 conditions, when growth occurred, but not in darkness or in the absence of CO2 , when growth was inhibited. N-sufficient cells subjected to conditions of N-starvation for a 24-h period showed a marked loss of photosynthetic activity. Upon supply of NH4 + , N-starved cells sufflated with CO2 air exhibited a time-dependent recovery of photosynthetic activity, both when suspended in light and in darkness. By contrast, growth only occurred in cells suspended in light. N-starved cells absorbed NH4 + in darkness, but at a lower rate than in light. All of these data suggest that dark NH4 + uptake is driven by N assimilation to recover from N-starvation and that the light-dependent NH4 + uptake is driven by growth, being then influenced by conditions that affect recovery or growth. Unlike CO2 conditions, in a CO2 -free atmosphere, absorption of NH4 + by N-starved cells occurred at a higher rate in darkness than in light. Accordingly, resumption of photosynthetic potential after NH4 + supply occurred in darkened cells, but not in illuminated cells. Respiratory activity of N-starved cells was enhanced up to 3-fold by NH4 + and 2-fold by methylammonium, with different patterns, suggesting that respiratory enzymes were affected by N-metabolism, especially through short-term control mechanisms triggered by the expenditure of metabolic energy involved in N-metabolism. 相似文献
993.
Daniele A Cardillo G Pennino C Carbone MT Scognamiglio D Esposito L Correra A Castaldo G Zagari A Salvatore F 《Biochimica et biophysica acta》2008,1782(6):378-384
Hyperphenylalaninemia is a group of autosomal recessive disorders caused by a wide range of phenylalanine hydroxylase (PAH) gene variants. To study the effects of mutations on PAH activity, we have reproduced five mutations (p.N223Y, p.R297L, p.F382L, p.K398N and p.Q419R) that we recently identified in a population of Southern Italy. Transient expression of mutant full-length cDNAs in human HEK293 cells yielded PAH variants whose l-phenylalanine hydroxylase activity was between 40% and 70% that of the wild-type enzyme. Moreover, Western blot analysis revealed a 50-kD monomer in all mutants thereby indicating normal synthesis of the mutant proteins. Because of the clinical mild nature of the phenotypes we performed an in vivo BH4 loading test. This was positive in all tested patients, which indicates that they are likely to respond to the coenzyme in vivo. We also analysed the environment of each mutation site in the available crystal structures of PAH by using molecular graphics tools. The structural alteration produced by each mutation was elucidated and correlated to the mutated properties of the mutant enzymes. All the data obtained demonstrate the disease-causing nature of the five novel variants. 相似文献
994.
Roberto Esposito Franco Cilli Valentina Pieramico Antonio Ferretti Antonella Macchia Marco Tommasi Aristide Saggino Domenico Ciavardelli Antonietta Manna Riccardo Navarra Filippo Cieri Liborio Stuppia Armando Tartaro Stefano L. Sensi 《PloS one》2013,8(7)
Background
There is growing debate on the use of drugs that promote cognitive enhancement. Amphetamine-like drugs have been employed as cognitive enhancers, but they show important side effects and induce addiction. In this study, we investigated the use of modafinil which appears to have less side effects compared to other amphetamine-like drugs. We analyzed effects on cognitive performances and brain resting state network activity of 26 healthy young subjects.Methodology
A single dose (100 mg) of modafinil was administered in a double-blind and placebo-controlled study. Both groups were tested for neuropsychological performances with the Raven’s Advanced Progressive Matrices II set (APM) before and three hours after administration of drug or placebo. Resting state functional magnetic resonance (rs-FMRI) was also used, before and after three hours, to investigate changes in the activity of resting state brain networks. Diffusion Tensor Imaging (DTI) was employed to evaluate differences in structural connectivity between the two groups. Protocol ID: Modrest_2011; ; http://clinicaltrials.gov/ct2/show/ NCT01684306. NCT01684306Principal Findings
Results indicate that a single dose of modafinil improves cognitive performance as assessed by APM. Rs-fMRI showed that the drug produces a statistically significant increased activation of Frontal Parietal Control (FPC; p<0.04) and Dorsal Attention (DAN; p<0.04) networks. No modifications in structural connectivity were observed.Conclusions and Significance
Overall, our findings support the notion that modafinil has cognitive enhancing properties and provide functional connectivity data to support these effects.Trial Registration
ClinicalTrials.gov http://clinicaltrials.gov/ct2/show/ NCT01684306. NCT01684306相似文献995.
Rimbault B Esposito D Drapier D Choquet Y Stern D Wollman FA 《Molecular & general genetics : MGG》2000,264(4):486-491
The chloroplast atpB gene of Chlamydomonas reinhardtii, which encodes the beta subunit of the ATP synthase, contains three in-frame ATGs that are candidate translation initiation codons. An earlier study revealed that the N terminus of the assembled beta subunit maps at the +2 position with respect to the second in-frame methionine codon (Fiedler et al. 1995). Using chloroplast transformation, we have examined the possibility that either of the two additional in-frame ATG codons is competent for translation initiation. We provide evidence that translation of atpB is initiated exclusively at the second ATG codon. We conclude that the beta subunit is not synthesized with an N-terminal leader before its assembly into a functional ATP synthase complex. 相似文献
996.
997.
S Lombardi F Esposito F Zavala L Lamizana P Rossi G Sabatinelli R S Nussenzweig M Coluzzi 《Parassitologia》1986,28(2-3):113-116
Indoor resting Anopheles gambiae s.l. were collected in two villages near Ouagadougou, Burkina Faso, and processed to investigate the presence and distribution of Plasmodium sporozoites. Salivary glands were dissected, examined by phase contrast microscopy and further processed by IRMA in order to reveal the presence of the circumsporozoite (CS) antigen of P. falciparum. The corresponding thoraces were homogenized and processed by IRMA. In the village characterized by the higher inoculation rate more than 40% of the infected mosquitoes were not found infective since CS antigen was detected in the thorax in absence of sporozoites and CS antigen in the corresponding salivary glands. 相似文献
998.
999.
Elisabetta Ullu Vincenzo Esposito Marialuisa Melli 《Journal of molecular biology》1982,161(1):195-201
The cloning and characterization of the cytoplasmic 7 S RNAs of HeLa cells has provided pure probes to study the organization of the corresponding genomic DNA sequences. Such analysis has shown that the 7 S L and K RNAs are derived from families of middle repetitive DNA (Ullu & Melli, 1982; Ullu et al., 1982). In this work we analyze the evolutionary conservation of these sequences in the RNA and DNA of distantly related species. Hybridization of the 7 S recombinants to the RNA of rodents, birds, amphibians and echinoderms suggests high conservation of these sequences throughout evolution. Southern blot analysis of genomic DNAs from the same species shows the presence of families of repeated sequences homologous to the 7 S recombinants and Alu DNAs in the genomes of the same species. We were unable to hybridize the 7 S probes to the RNAs of Drosophila melanogaster or Dictyostelium discoideum, although sequence(s) homologous to the 7 S L probe were found in the genome of D. discoideum and to both 7 S L and K probes in the genome of D. melanogaster. 相似文献
1000.
S B Linhart F S Blom G J Dasch J D Roberts R M Engeman J J Esposito J H Shaddock G M Baer 《Journal of wildlife diseases》1991,27(1):21-33
Captive raccoons were offered a variety of vaccine containers and bait components in a series of three-choice tests. Paraffin wax ampules were the most readily accepted vaccine container. Preferred bait components included corn and shellfish oils, deep fried corn meal batter, and egg, apple and buttermilk flavorings. These results, together with factors including ease of bait formulation, cost, and suitability for field use, were used to develop an experimental delivery system for an oral rabies vaccine. The developed system was composed of a polyurethane sleeve (1.5 x 5.5 cm) dipped in a commercial food batter mix together with corn meal, milk and egg. The sleeve was deep fried in corn oil and a 2.0 ml ampule containing a recombinant rabies vaccine was then inserted into the sleeve bait. These baits were presented to 10 captive raccoons. Nine of the 10 animals developed high levels of rabies virus neutralizing antibodies. Field tests are needed to determine if the delivery system developed also is effective for wild raccoons. 相似文献