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1.
Gianfranco Sebastio Ornella Castiglione Barbara Incerti Donatello Salvatore Francesca Santamaria 《Human genetics》1990,85(4):430-431
Summary Fifty one independent cystic fibrosis (CF) families originating from a restricted area of Southern Italy (Campania) have been
analyzed for KM19 and XV2c haplotypes and the ΔF508 mutation: 54% of the total CF chromosomes show the ΔF508 mutation. No
significative correlations were obtained when clinical score, radiological score,Pseudomonas colonization, or clinical symptoms at presentation were matched with the presence or absence of the ΔF508 mutation. 相似文献
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Silene ichnusae (Caryophyllaceae) a new species of S. sect. Siphonomoipha is described and illustrated. It is a rare chasmophyte localized at Capo Falcone (W Sardinia), on siliceous rocks near the sea. Its relationships with S. velutina, of the S. mollissima group, are discussed. 相似文献
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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
6.
Giuliano Bonanomi Guido Incerti Gaspare Cesarano Salvatore A. Gaglione Virginia Lanzotti 《PloS one》2015,10(1)
Cigarette butts (CBs) are the most common type of litter on earth, with an estimated 4.5 trillion discarded annually. Apart from being unsightly, CBs pose a serious threat to living organisms and ecosystem health when discarded in the environment because they are toxic to microbes, insects, fish and mammals. In spite of the CB toxic hazard, no studies have addressed the effects of environmental conditions on CB decomposition rate. In this study we investigate the interactive effects of substrate fertility and N transfer dynamics on CB decomposition rate and carbon quality changes. We carried out an experiment using smoked CBs and wood sticks, used as a slow decomposing standard organic substrate, incubated in both laboratory and field conditions for two years. CB carbon quality changes during decomposition was assessed by 13C CPMAS NMR. Our experiment confirmed the low degradation rate of CBs which, on average, lost only 37.8% of their initial mass after two years of decomposition. Although a net N transfer occurred from soil to CBs, contrary to our hypothesis, mass loss in the medium-term (two years) was unaffected by N availability in the surrounding substrate. The opposite held for wood sticks, in agreement with the model that N-rich substrates promote the decomposition of other N-poor natural organic materials with a high C/N ratio. As regards CB chemical quality, after two years of decomposition 13C NMR spectroscopy highlighted very small changes in C quality that are likely to reflect a limited microbial attack. 相似文献
7.
Carla Carluccio Francesco Salvatore Arianna Fornili 《Journal of biomolecular structure & dynamics》2016,34(3):497-507
The enzyme phenylalanine hydroxylase (PAH) is defective in the inherited disorder phenylketonuria. PAH, a tetrameric enzyme, is highly regulated and displays positive cooperativity for its substrate, Phe. Whether Phe binds to an allosteric site is a matter of debate, despite several studies worldwide. To address this issue, we generated a dimeric model for Phe–PAH interactions, by performing molecular docking combined with molecular dynamics simulations on human and rat wild-type sequences and also on a human G46S mutant. Our results suggest that the allosteric Phe-binding site lies at the dimeric interface between the regulatory and the catalytic domains of two adjacent subunits. The structural and dynamical features of the site were characterized in depth and described. Interestingly, our findings provide evidence for lower allosteric Phe-binding ability of the G46S mutant than the human wild-type enzyme. This also explains the disease-causing nature of this mutant. 相似文献
8.
Angela Avenoso Angela D'Ascola Michele Scuruchi Giuseppe Mandraffino Salvatore Campo Giuseppe M. Campo 《Biochimica et Biophysica Acta (BBA)/General Subjects》2021,1865(1):129731
BackgroundSmall HA fragments are produced during cartilage degradation and their role seems to be preponderant during pathologies in which cartilage injury contribute to trigger and perpetuate the inflammatory mechanism.Several reports have increasingly shown that MicroRNAs (miRs), a small non-coding mRNAs are involved in the regulation of multiple biological processes, including cell proliferation and inflammation response in different pathologies, among them miR146a seems to be involved in inflammatory processes.MethodsStarting by these evidences we investigated the levels of miR146a and its correlation with inflammatory mediators in an experimental model of 6-mer HA-induced inflammatory response in human cultured chondrocytes.ResultsTreatment of chondrocytes with 6-mer HA showed up-regulation in inflammation parameters such as TLR-4, and CD44 receptors activation, IL-6, IL-1β and MMP-13 mRNA expression and proteins production, as well as NF-kB activation. We also revealed an up-regulation of miR146a. Transfection with a miR146a mimic or miR146a inhibitor produced the following effects: chondrocytes receiving miR146a mimic and then 6-mer HA significantly reduced inflammatory cytokines and MMP-13, while exposition of chondrocytes with miR146a inhibitor and then the 6-mer HA incremented the activity of damaging cytokines and MMP13. Expression of CD44 receptor was not affected by miR-146a treatments, while TLR-4 expression and NF-kB activation were modified.ConclusionsWe concluded that up-regulation of miR146a occurred in 6-mer HA-induced inflammation response may reduce the inflammatory cascade by modulating TLR-4 and NF-kB activation.General significanceThese results could be useful in develop new therapeutic strategies with the aim to reduce OA and RA incidence. 相似文献
9.
Lorenzo Chiariotti Paola Salvatore Rodolfo Frunzio Carmelo B. Bruni 《Glycoconjugate journal》2002,19(7-9):441-449
In this review we have summarized the more recent studies on the expression of mammalian galectins. One interesting observation that can be made is that in most of microarrays and/or differential display analysis performed in recent years one or more galectins have been picked up. From a critical evaluation of the pertinent studies the main conclusion that can be drawn is that, although it is not yet clear whether the 14 galectins identified so far have functions in common, a striking common feature of all galectins is the strong modulation of their expression during development, differentiation stages and under different physiological or pathological conditions. This suggests that the expression of different galectins is finely tuned and possibly coordinated. In spite of these observations it is rather unexpected that very few studies have been performed on the molecular mechanisms governing the activity of galectin genes. Published in 2004. 相似文献
10.
Steven L. Gonias Salvatore V. Pizzo 《Biochimica et Biophysica Acta (BBA)/General Subjects》1981,678(2):268-274
Clearance studies were performed in mice using α2-macroglobulin (α2M), α2M-trypsin comlex and α2M-CH3NH2 complex. All three species were incubated with cis-dichlorodiamine platinum(II) (cis-DDPt) at concentrations between 9.0 μM and 1.67 mM for 4 h and then dialyzed. The clearance rate of native α2M was unchanged following incubation with cis-DDPt. α2M-trypsin and α2M-CH3NH2 cleared rapidly from the ciruculation; however, reaction with cis-DDPt significantly decreased the plasma elimination rate of both complexes. Non-denaturing gel electrophoresis and α2M activity assays demonstrated relative stability following incubations with cis-DDPt which markedly altered clearance. Evidence for cis-DDPt crosslinking of α2M subunits was obtained: however, whether this crosslinking is involved in altered clearance remains undetermined. Iodoacetamide treatment of α2M did not duplicate the effect of cis-DDPton α2M clearance, nor did it inhibit the effect of cis-DDPt on α2M clearance. Plasma elimination of α2M complex was also unaltered by pretreatment of mice with intravenous free cis-DDPt. 相似文献