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51.
Valeria Edefonti Francesca Bravi Katherine Turner Ettore Beghi Maria Paola Canevini Monica Ferraroni Ada Piazzini 《BMC neurology》2011,11(1):33
Background
The potential effect of age-related factors on health-related quality of life (HRQOL) of patients with epilepsy has rarely been analyzed in the literature. 相似文献52.
53.
54.
Zubrzak P Banaś A Kaczmarek K Leplawy MT Sochacki M Kowalski ML Szkudlińska B Zabrocki J Di Lello P Isernia C Saviano M Pedone C Benedetti E 《Biopolymers》2005,80(2-3):347-356
Linear and cyclic cyclolinopeptide A (CLA) analogues containing alpha-hydroxymethylleucine (HmL) in positions 1, 4, and 1&4, and alpha-hydroxymethylvaline (HmV) in position 5, were synthesized by the solid-phase peptide strategy and cyclized with the 1-Ethyl-3-(3-dimethylaminopropyl)-carbodiimide/1-hydroxy-7-azabenzotriazole (EDC/HOAt) reagent. The peptides were examined for their immunosuppressive activity in the lymphocyte proliferation assays (LPA). Only HmL-containing peptides demonstrated at about 25% lower immunosuppressive activity, but they are four times more soluble in water solutions than the native CLA. It seems from the LPA results that peptide [(HmL4)CLA] is the most promising for further studies. This peptide was characterized in solution, at room temperature in CDCl3, and the conformation compared with that observed for CLA in the solid state. 相似文献
55.
Olmo E 《Genetica》2005,125(2-3):185-203
The chromosome changing rate (i.e. the number of chromosome rearrangements per million years) was studied in 1329 reptile
species in order to evaluate the karyological evolutionary trend and the existence of possible correlations between chromosome
mutations and some aspects of the evolution of this class. The results obtained highlight the existence of a general direct
correlation between chromosome changing rate and number of living species, although different trends can be observed in the
different orders and suborders. In turtles, the separation of pleurodires from cryptodires was accompanied by a considerable
karyological diversification. Among pleurodires, the evolution of the Chelidae and Pelomedusidae was also characterised by
chromosome variation, while in cryptodires a marked karyological homogeneity is observed between and within infraorders. Similarly
there is no correlation between changing rate and species number in crocodiles, where the evolution of the families and genera
has entailed few chromosome mutations. Chromosome variability was greater in lizards and snakes. In the formers variations
in chromosome changing rate accompanied the separation of the infraorders and the evolution of most of the families and of
some genera. The origin of snakes has also been accompanied by a marked karyological diversification, while the subsequent
evolution of the infraorders and families has entailed a high level of chromosome variability only in colubroids. The karyological
evolution in reptiles generally entailed a progressive reduction in chromosome changing rate, albeit with differences in the
diverse orders and suborders. This trend seems to be consistent with the “canalization model” as originally proposed by Bickham
and Baker in [Bickham, J.W. & R J. Baker, 1979. Bull. Carnegie Mus. Nat. Hist. 13: 70–84.]
However, several inconsistencies have been found excluding that in this class the ultimate goal of chromosome variations
was the achievement of a so-called ``optimum karyotype' as suggested by the above-mentioned theory. Other mechanisms could
underpin chromosome variability in Reptiles. Among them a genomic composition more or less favourable to promoting chromosome
rearrangements and factors favouring the fixation of a mutant karyotype in condition of homozygosis. Turtles and crocodiles
would have a genome characterised by large chromosomes and a low level of chromosome compartmentalisation limiting the recombination
and the frequency of rearrangements. A low rate of chromosome variability modifying little if at all the gene linkage groups
would have favoured a conservative evolutionary strategy. In the course of evolution, lizards and snakes could have achieved
a genome characterised by smaller chromosomes and a higher level of compartmentalisation. This would have raised the frequency
of recombination and consequently an evolutionary strategy promoting a higher degree of variability and a greater level of
speciation. 相似文献
56.
Baccante G Mincione G Di Marcantonio MC Piccirelli A Cuccurullo F Porreca E 《Biochemical and biophysical research communications》2004,314(3):704-710
Statins have been shown to interact with several monocyte/macrophage functions. We tested the effect of pravastatin on transforming growth factor-beta1 (TGF-beta1) production and its possible involvement in scavenger receptors class A (SRA) expression in human THP-1 cells. TGF-beta1s biological activity in THP-1 cell conditioned medium, evaluated by luciferase activity of transfected cell with a TGF-beta responsive promoter, was increased in a dose-dependent manner after incubation with pravastatin (1-20 microM). Pravastatin (1-20 microM) induced a dose-dependent increase in TGF-beta1 mRNA expression and protein production in THP-1 cells. PMA-induced SRA gene and protein expression was suppressed by pravastatin with a mean 3-fold decrease at 10 microM. This last effect was reversed by a mouse monoclonal anti-TGF-beta1 neutralizing antibody. PD98059, a specific inhibitor of MAP kinase cascade, completely reversed pravastatin-induced SRA down-regulation. p44 and p42 isoforms showed a dose-dependent phosphorylation after treatment with pravastatin (1-20 microM) which was inhibited by a mouse monoclonal anti-TGF-beta1 antibody. Our results demonstrate that pravastatin significantly up-regulates TGF-beta1 expression which may be in involved in down-regulation of SRA expression in THP-1 cell cultures. A new pathway for pravastatin effects in atherogenesis can be suggested. 相似文献
57.
Scatena R Bottoni P Martorana GE Ferrari F De Sole P Rossi C Giardina B 《Biochemical and biophysical research communications》2004,319(3):967-973
Peroxisome proliferator activated receptors (PPARs) are a class of nuclear receptors involved in lipid and glucidic metabolism, immune regulation, and cell differentiation. Many of their biological activities have been studied by using selective synthetic activators (mainly fibrates and thiazolidinediones) which have been already employed in therapeutic protocols. Both kinds of drugs, however, showed pharmacotoxicological profiles, which cannot be ascribed by any means to receptor activation. To better understand these non-receptorial or extrareceptorial aspects, the effect of different PPAR-ligands on the metabolic status of human HL-60 cell line has been investigated. At this regard, NMR analysis of cell culture supernatants was accomplished in order to monitor modifications at the level of cell metabolism. Cell growth and chemiluminescence assays were employed to verify cell differentiation. Results showed that all the considered PPAR-ligands, although with different potencies and independently from their PPAR binding specificity, induced a significant derangement of the mitochondrial respiratory chain consisting in a strong inhibition of NADH-cytochrome c reductase activity. This derangement has been shown to be strictly correlated to the adaptive metabolic modifications, as evidenced by the increased formation of lactate and acetate, due to the stimulation of anaerobic glycolysis and fatty acid beta-oxidation. It is worthy noting that the mitochondrial dysfunction appeared also linked to the capacity of any given PPAR-ligand to induce cell differentiation. These data could afford an explanation of biochemical and toxicological aspects related to the therapeutic use of synthetic PPAR-ligands and suggest a revision of PPAR pathophysiologic mechanisms. 相似文献
58.
Barucca M Biscotti MA Olmo E Canapa A 《Journal of experimental zoology. Part B. Molecular and developmental evolution》2006,306(2):164-167
The ParaHox gene cluster contains three homeobox genes, Gsx, Xlox and Cdx and has been demonstrated to be an evolutionary sister of the Hox gene cluster. Among deuterostomes the three genes are found in the majority of taxa, whereas among protostomes they have so far been isolated only in the phylum Sipuncula.We report the partial sequences of all three ParaHox genes in the polyplacophoran Nuttallochiton mirandus, the first species of the phylum Mollusca where all ParaHox genes have been isolated. This finding has phylogenetic implications for the phylum Mollusca and for its relationships with the other lophotrochozoan taxa. 相似文献
59.
Proteomic analysis of membrane microdomains derived from both failing and non-failing human hearts 总被引:3,自引:0,他引:3
Banfi C Brioschi M Wait R Begum S Gianazza E Fratto P Polvani G Vitali E Parolari A Mussoni L Tremoli E 《Proteomics》2006,6(6):1976-1988
Eukaryotic cells plasma membranes are organized into microdomains of specialized function such as lipid rafts and caveolae, with a specific lipid composition highly enriched in cholesterol and glycosphingolipids. In addition to their role in regulating signal transduction, multiple functions have been proposed, such as anchorage of receptors, trafficking of cholesterol, and regulation of permeability. However, an extensive understanding of their protein composition in human heart, both in failing and non-failing conditions, is not yet available. Membrane microdomains were isolated from left ventricular tissue of both failing (n = 15) and non-failing (n = 15) human hearts. Protein composition and differential protein expression was explored by comparing series of 2-D maps and subsequent identification by LC-MS/MS analysis. Data indicated that heart membrane microdomains are enriched in chaperones, cytoskeletal-associated proteins, enzymes and protein involved in signal transduction pathway. In addition, differential protein expression profile revealed that 30 proteins were specifically up- or down-regulated in human heart failure membrane microdomains. This study resulted in the identification of human heart membrane microdomain protein composition, which was not previously available. Moreover, it allowed the identification of multiple proteins whose expression is altered in heart failure, thus opening new perspectives to determine which role they may play in this disease. 相似文献
60.
Francesca Marini Alberto Falchetti Del Francesca Monte Silvia Carbonell Sala Alessia Gozzini Ettore Luzi Maria Luisa Brandi 《Orphanet journal of rare diseases》2006,1(1):1-9
Solitary median maxillary central incisor syndrome (SMMCI) is a complex disorder consisting of multiple, mainly midline defects of development resulting from unknown factor(s) operating in utero about the 35th–38th day(s) from conception. It is estimated to occur in 1:50,000 live births. Aetiology is uncertain. Missense mutation in the SHH gene (I111F) at 7q36 may be associated with SMMCI. The SMMCI tooth differs from the normal central incisor, in that the crown form is symmetric; it develops and erupts precisely in the midline of the maxillary dental arch in both primary and permanent dentitions. Congenital nasal malformation (choanal atresia, midnasal stenosis or congenital pyriform aperture stenosis) is positively associated with SMMCI. The presence of an SMMCI tooth can predict associated anomalies and in particular the serious anomaly holoprosencephaly. Common congenital anomalies associated with SMMCI are: severe to mild intellectual disability, congenital heart disease, cleft lip and/or palate and less frequently, microcephaly, hypopituitarism, hypotelorism, convergent strabismus, oesophageal and duodenal atresia, cervical hemivertebrae, cervical dermoid, hypothyroidism, scoliosis, absent kidney, micropenis and ambiguous genitalia. Short stature is present in half the children. Diagnosis should be made by eight months of age, but can be made at birth and even prenatally at 18–22 weeks from the routine mid-trimester ultrasound scan. Management depends upon the individual anomalies present. Choanal stenosis requires emergency surgical treatment. Short stature may require growth hormone therapy. SMMCI tooth itself is mainly an aesthetic problem, which is ideally managed by combined orthodontic, prosthodontic and oral surgical treatment; alternatively, it can be left untreated. 相似文献