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1.
Vertical ionization energies (VIEs) of medazepam, nordazepam and their molecular subunits have been calculated using the electron
propagator method in the P3/CEP-31G* approximation. Vertical electron affinities (VEAs) have been obtained with a ∆SCF procedure
at the DFT-B3LYP/6-31+G* level of theory. Excellent correlations have been achieved between IEcalc and IEexp, allowing reliable assignment of the ionization processes. Our proposed assignment differs in many instances from that previously
reported in the literature. The electronic structure of the frontier Dyson orbitals shows that the IE and EA values of the
benzodiazepines can be modulated by substitution at the benzene rings. Hardness values, evaluated as (IE − EA)/2, follow the
trend of the experimental singlet transition energies. Medazepam is a less hard (i.e., less stable) compound than nordazepam. 相似文献
2.
A new human species of aldolase A mRNA from fibroblasts 总被引:2,自引:0,他引:2
P Izzo P Costanzo A Lupo E Rippa A M Borghese G Paolella F Salvatore 《European journal of biochemistry》1987,164(1):9-13
A full-length cDNA aldolase A clone was isolated from a human fibroblast cDNA library and completely sequenced. Excluding the poly(A) tail, the clone covers 1095 base pairs (bp) of the coding region, plus 199 bp downstream for the termination codon and 146 bp upstream for the initiation codon, within a total of 1440 bp. Primer extension experiments performed with human cultured fibroblast mRNA indicate an elongated product of a further 40 bp. These results evaluated together with those obtained in a concurrent study concerning aldolase A mRNA isolated from human liver are direct evidence of aldolase A mRNA multiplicity in man. The data also suggest the existence in mammals of three different classes of aldolase A mRNA, which would account for tissue specificity and resurgence of foetal expression in tumors. 相似文献
3.
Mapping of a restriction fragment length polymorphism within the human aldolase B gene 总被引:1,自引:0,他引:1
Giovanni Paolella Rita Santamaria Pasqualina Buono Francesco Salvatore 《Human genetics》1987,77(2):115-117
Summary Peripheral blood DNA was hybridized to the full-length cDNA and the cloned structural gene of human aldolase B. With PvuII endonuclease a restriction fragment length polymorphism was detected that was present in the heterozygous state in about 21% of the individuals tested. A map of the human aldolase gene was constructed for the two groups of individuals found to produce different fragments after PvuII digestion. This allowed the localization of the polymorphic site within the gene, which was found to be due to the loss of a PvuII site in the last intron upstream from the 3 end. This polymorphism may be used as a genetic marker to study individuals affected by hereditary fructose intolerance. 相似文献
4.
5.
T Improta A M Salvatore A Di Luzio G Romeo E M Coccia P Calissano 《Experimental cell research》1988,179(1):1-9
Natural or recombinant murine interferon-gamma causes a reversible arrest of proliferation of PC12 cells. Treatment with other antimitotics (AraC, colchicine, mitomycin C, hydroxyurea) or removal of serum, on the contrary, leads to mitotic arrest followed by cell death. IFN-gamma-treated PC12 cells respond more rapidly to NGF in terms of speed of neuronal outgrowth. On the other hand, NGF potentiates the action of IFN-gamma in stimulating the enzyme 2',5'-A synthetase which shifts from an average of 4.4-fold stimulation at 48 h with IFN-gamma alone to increments varying between 5- and 18-fold when PC12 cells are treated for 48 h with IFN-gamma and NGF. NGF alone, on the contrary, does not exert any detectable effect on this enzyme. From the findings we propose the use of a combined treatment of PC12 cells with NGF and IFN-gamma for a more rapid induction of neuronal differentiation. 相似文献
6.
Salvatore Oliviero Mario DeMarchi Angelo O. Carbonara Luigi F. Bernini Giuliano Bensi Giovanni Raugei 《Human genetics》1985,71(1):49-52
Summary The protein and gene structure of the Hp Johnson variant (Hp3) were analyzed in two related heterozygous individuals. The molecular weight (23kd) and amino acid composition of Hp3 alpha chain were in agreement with the triplicated structure first suggested by Smithies in 1964. Direct gene analysis by Southern blotting showed a three-fold tandem repeat of the same 1.7 kb DNA segment implicated in the Hp2 gene duplication. On the basis of these data a nine exon model for the Hp3 gene is proposed. 相似文献
7.
Lucio Annunziato Salvatore Amoroso Gianfranco Di Renzo Filomena Argenzio Caterina Aurilio Antonio Grella Aldo Quattrone 《Life sciences》1983,33(26):2651-2655
In humans the release of growth hormone (GH) elicited by dopamine (DA) and DA agonists may represent a reliable model to assess change in sensitivity of DA receptors. We now report that in chronic alcoholics, 4–7 days after the suspension of alcohol consumption, the increase of GH response to DA infusion was higher than that seen in non alcoholic volunteers. The specificity of this GH response to DA administration was demonstrated by the use of domperidone, a novel peripheral antagonist of DA receptors. These results suggest the development of hyper-responsiveness of DA receptors involved in the control of GH secretion in chronic alcoholics during the later phases of the “withdrawal syndrome”. 相似文献
8.
Maureane Hoffman Steven R. Feldman Salvatore V. Pizzo 《Biochimica et Biophysica Acta (BBA)/General Subjects》1983,760(3):421-423
Mouse peritoneal macrophages activated by bacillus Calmette-Guerin (BCG) were incubated with human α2-macroglobulin converted to its ‘fast’ form with either trypsin or methylamine before being stimulated with phorbol myrystate acetate. Both α2-macroglobulin-trypsin and α2-macroglobulin-methylamine inhibited macrophage production of superoxide anion (O2−) while native α2-macroglobulin had little effect except at high concentration. The α2-macroglobulin ‘fast’ forms, which bind with a Kd of about 8 nM, inhibited 50% generation of O2−(ID50) at a concentration of 7 nM while α2-macroglobulin inhibited O2− production with an ID50 of 141 nM. The ‘fast’ forms of α2-macroglobulin may play a role in the feedback regulation of inflammatory reactions. 相似文献
9.
10.
C Feuerstein R Peretti-Renucci M Savasta B Scatton M Manier A Dubois J Thibault N Mons M Geffard 《Analytical cellular pathology》1989,1(3):153-171
Major technical progress in the development of computer-based image analysis systems has made possible the entry of autoradiographic and immunohistochemical techniques into a new era where quantification via densitometry and morphometry has become easily accessible. In this context, quantitative biochemical data can be adapted to anatomical and histological resolution. This adaptation is most efficient in the neuroscience fields because of the huge importance of cellular communication via neuronal networks in the nervous system. Therefore, any experimental approach to the brain which considers the brain as a 'black box' appears now as very crude. In fact, subtle heterogeneity in the distribution of biochemical markers can now be demonstrated, as illustrated here by the use of quantitative autoradiography of D1 and D2 dopaminergic receptors in the striatum of the mammalian brain. Also, local adaptive changes resulting from chronic blockade of the dopaminergic input can be detected after repeated treatments with dopaminergic antagonists selective for D1 or D2 receptors or with surgical lesioning of the dopaminergic nigrostriatal pathway. The resulting plastic changes are unevenly distributed throughout the striatal target organ and vary according to the mode of suppressing the dopaminergic flow: direct destruction of the dopaminergic pathway or selective pharmacological manipulation without physical elimination of the dopaminergic cells themselves. All these results are discussed and reviewed in light of the most recent reports in this field. 相似文献