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71.
Kariz S Milutinović A Bregar D Terzić I Terzić R Lovrecić L Herova M Hruskovicova H Peterlin B Petrovic D Zorc-Pleskovic R 《Collegium antropologicum》2007,31(2):503-507
In this study we investigated the association of the interleukin-1 receptor antagonist gene variable number tandem repeat (IL1RN VNTR) polymorphism and of the inhibitor of kappa B-like protein (IKBL) gene polymorphism with myocardial infarction (MI) in a group of patients with type 2 diabetes. The IL1RN VNTR and the IKBL+ 738T > C gene polymorphisms were tested in 374 Caucasians: 151 cases with MI and 223 subjects with no history of coronary artery disease. The IL1RN VNTR polymorphism was not a risk factor for MI in Caucasians with type 2 diabetes (genotype 22 vs. the rest: odds ratio (OR) 1.6; 95% confidence interval (CI) = 0.8-3.5; p = 0.2). We also failed to demonstrate that IKBL+ 738T > C gene polymorphism was associated with MI in patients with type 2 diabetes (OR = 0.9; 95% CI = 0.3-2.6; p = 0.9). We provide evidence that the IL1RN VNTR and the IKBL + 738T > C gene polymorphisms are not risk factors for MI in Caucasians with type 2 diabetes. 相似文献
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Verde C Howes BD De Rosa MC Raiola L Smulevich G Williams R Giardina B Parisi E Di Prisco G 《Protein science : a publication of the Protein Society》2004,13(10):2766-2781
The suborder Notothenioidei dominates the Antarctic ichthyofauna. The non-Antarctic monotypic family Pseudaphritidae is one of the most primitive families. The characterization of the oxygen-transport system of euryhaline Pseudaphritis urvillii is herewith reported. Similar to most Antarctic notothenioids, this temperate species has a single major hemoglobin (Hb 1, over 95% of the total). Hb 1 has strong Bohr and Root effects. It shows two very uncommon features in oxygen binding: At high pH values, the oxygen affinity is exceptionally high compared to other notothenioids, and subunit cooperativity is modulated by pH in an unusual way, namely the curve of the Hill coefficient is bell-shaped, with values approaching 1 at both extremes of pH. Molecular modeling, electronic absorption and resonance Raman spectra have been used to characterize the heme environment of Hb 1 in an attempt to explain these features, particularly in view of some potentially important nonconservative replacements found in the primary structure. Compared to human HbA, no major changes were found in the structure of the proximal cavity of the alpha-chain of Hb 1, although an altered distal histidyl and heme position was identified in the models of the beta-chain, possibly facilitated by a more open heme pocket due to reduced steric constraints on the vinyl substituent groups. This conformation may lead to the hemichrome form identified by spectroscopy in the Met state, which likely fulfils a potentially important physiological role. 相似文献
75.
Tripodi SA Del Vecchio MT Supuran CT Scozzafava A Gabrielli MG Pastorekova S Rossie R Fasolis G Puccetti L 《Journal of enzyme inhibition and medicinal chemistry》2004,19(3):287-291
Clear renal cell carcinomas (RCC) frequently express carbonic anydrase IX (CA IX) because of non-functional mutation of von Hippel Lindau (VHL) tumor suppressor gene. CA IX is a tumor-associated transmembrane antigen, which catalyzes the extracellular, reversible hydration of carbon dioxide to bicarbonate and proton and thereby contributes to acidification of extracellular milieu. Extracellular acidic pH facilitates tumor growth and progression. CA IX expression is upregulated by Hypoxia Inducible Factor-1 (HIF-1), which is negatively controlled by oxygen via wild type VHL protein and is also regulated by the cell redox state. We investigated the immunohistochemical pattern of distribution of CA IX in a small series (14 cases) of RCCs. CA IX expression was matched with the redox state of RCC, stratifying our series in relation to clinical and histopathological parameters, such as Fuhrman grade, staging, proliferation markers expression, and particularly, the presence of necrosis. Our results show for the first time the existence of a perivascular pattern of CA IX distribution in RCC. We also found a significant relationship between CA IX expression and the presence of necrosis. Tumors with higher CA IX expression exhibited higher degree of necrosis (p < 0.05). Notably, an almost significant relationship between the redox state and CA IX expression was detected in RCC patients with 5 years disease-free survival, most of them showing organ-confined disease. Tumors with lower redox state showed an algebraically higher degree of CA IX expression. On the contrary, tumors with higher redox state exhibited an algebraically lower CA IX expression (p = 0.057). The observed relationship of CA IX expression and necrosis suggests a role for CA IX in RCC. Further investigations are necessary to further establish the role of the redox state in regulation of CA IX expression in RCC. 相似文献
76.
The Cercopithecini, or African guenon monkeys, are one of the most diverse clades of living primates and comprise the most species‐rich clade of Catarrhini. Species identity is announced by flamboyant coloration of the facial and genital regions and, more cryptically, by vigorous chromosomal rearrangements among taxa. Beneath the skin, however, these animals are skeletally conservative and show low levels of genetic sequence divergence consonant with recent divergence between congeneric species. The guenons clearly demonstrate that morphological, cytogenetic, and reproductive differentiation proceed at different rates during speciation. We review diverse kinds of data in an effort to understand this conundrum. 相似文献
77.
Preliminary analysis of reproductive success in a large mammal with alternative mating tactics,the Northern chamois,Rupicapra rupicapra 下载免费PDF全文
Luca Corlatti Bruno Bassano Radka Poláková Lorenzo Fattorini Maria Chiara Pagliarella Sandro Lovari 《Biological journal of the Linnean Society. Linnean Society of London》2015,116(1):117-123
In polygynous mating systems, reproductive skew depends on the ability of males to monopolize females, which in turn may promote the development of contrasting traits in the two sexes. Although dominant individuals normally enjoy a higher reproductive success (RS) than subordinates, the use of genetic markers has shown that behavioural observations of male mating success may not provide reliable clues of RS. We report the preliminary results of the first DNA‐based paternity analysis on the Northern chamois (Rupicapra rupicapra), a scarcely dimorphic mountain ungulate described as highly polygynous, in relation to mating tactic and age. Because of sampling difficulties, the success in parentage assignment was low, and the interpretation of results requires caution. Territorial males had a greater RS than nonterritorial ones but they were unable to monopolize mating events. Age had a weak effect on paternity outcome but only males ≥ 6 years showed siring success. Although future studies are needed to assess the opportunity for sexual selection in male chamois, the concurrence of limited sexual size dimorphism, compensatory growth, unbiased sex‐specific survival, RS of alternative mating tactics and, possibly, long breeding tenure, may hint at the adoption of a conservative mating strategy in this species. 相似文献
78.
Raffaele Lombardi Patrizia Circelli Maria Elena Villani Giampaolo Buriani Luca Nardi Valentina Coppola Linda Bianco Eugenio Benvenuto Marcello Donini Carla Marusic 《BMC biotechnology》2009,9(1):96
Background
In recent years, different HIV antigens have been successfully expressed in plants by either stable transformation or transient expression systems. Among HIV proteins, Nef is considered a promising target for the formulation of a multi-component vaccine due to its implication in the first steps of viral infection. Attempts to express Nef as a single protein product (not fused to a stabilizing protein) in transgenic plants resulted in disappointingly low yields (about 0.5% of total soluble protein). In this work we describe a transient expression system based on co-agroinfiltration of plant virus gene silencing suppressor proteins in Nicotiana benthamiana, followed by a two-step affinity purification protocol of plant-derived Nef. 相似文献79.
Sapone A Gustavino B Monfrinotti M Canistro D Broccoli M Pozzetti L Affatato A Valgimigli L Forti GC Pedulli GF Biagi GL Abdel-Rahman SZ Paolini M 《Mutation research》2007,626(1-2):143-154
Epidemiological evidence suggests a link between consumption of chlorinated drinking water and various cancers. Chlorination of water rich in organic chemicals produces carcinogenic organochlorine by-products (OBPs) such as trihalomethanes and haloacetic acids. Since the discovery of the first OBP in the 1970s, there have been several investigations designed to determine the biological effects of single chemicals or small artificial OBP combinations. However, there is still insufficient information regarding the general biological response to these compounds, and further studies are still needed to evaluate their potential genotoxic effects. In the current study, we evaluated the effect of three drinking water disinfectants on the activity of cytochrome P450 (CYP)-linked metabolizing enzymes and on the generation of oxidative stress in the livers of male and female Cyprinus carpio fish (carp). The fish were exposed in situ for up 20 days to surface water obtained from the Trasmene lake in Italy. The water was treated with 1-2 mg/L of either sodium hypochlorite (NaClO) or chlorine dioxide (ClO2) as traditional disinfectants or with a relatively new disinfectant product, peracetic acid (PAA). Micronucleus (MN) frequencies in circulating erythrocytes from the fish were also analysed as a biomarker of genotoxic effect. In the CYP-linked enzyme assays, a significant induction (up to a 57-fold increase in the deethylation of ethoxyresorufin with PAA treatment) and a notable inactivation (up to almost a 90% loss in hydroxylation of p-nitrophenol with all disinfectants, and of testosterone 2beta-hydroxylation with NaClO) was observed in subcellular liver preparations from exposed fish. Using the electron paramagnetic resonance (EPR) spectroscopy radical-probe technique, we also observed that CYP-modulation was associated with the production of reactive oxygen species (ROS). In addition, we found a significant increase in MN frequency in circulating erythrocytes after 10 days of exposure of fish to water treated with ClO2, while a non-significant six-fold increase in MN frequency was observed with NaClO, but not with PAA. Our data suggest that the use of ClO2 and NaClO to disinfect drinking water could generate harmful OBP mixtures that are able to perturb CYP-mediated reactions, generate oxidative stress and induce genetic damage. These data may provide a mechanistic explanation for epidemiological studies linking consumption of chlorinated drinking water to increased risk of urinary, gastrointestinal and bladder cancers. 相似文献
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