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151.
Bernardinelli L Murgia SB Bitti PP Foco L Ferrai R Musu L Prokopenko I Pastorino R Saddi V Ticca A Piras ML Cox DR Berzuini C 《PloS one》2007,2(5):e480
Multiple genome screens have been performed to identify regions in linkage or association with Multiple Sclerosis (MS, OMIM 126200), but little overlap has been found among them. This may be, in part, due to a low statistical power to detect small genetic effects and to genetic heterogeneity within and among the studied populations. Motivated by these considerations, we studied a very special population, namely that of Nuoro, Sardinia, Italy. This is an isolated, old, and genetically homogeneous population with high prevalence of MS. Our study sample includes both nuclear families and unrelated cases and controls. A multi-stage study design was adopted. In the first stage, microsatellites were typed in the 17q11.2 region, previously independently found to be in linkage with MS. One significant association was found at microsatellite D17S798. Next, a bioinformatic screening of the region surrounding this marker highlighted an interesting candidate MS susceptibility gene: the Amiloride-sensitive Cation Channel Neuronal 1 (ACCN1) gene. In the second stage of the study, we resequenced the exons and the 3' untranslated (UTR) region of ACCN1, and investigated the MS association of Single Nucleotide Polymorphisms (SNPs) identified in that region. For this purpose, we developed a method of analysis where complete, phase-solved, posterior-weighted haplotype assignments are imputed for each study individual from incomplete, multi-locus, genotyping data. The imputed assignments provide an input to a number of proposed procedures for testing association at a microsatellite level or of a sequence of SNPs. These include a Mantel-Haenszel type test based on expected frequencies of pseudocase/pseudocontrol haplotypes, as well as permutation based tests, including a combination of permutation and weighted logistic regression analysis. Application of these methods allowed us to find a significant association between MS and the SNP rs28936 located in the 3' UTR segment of ACCN1 with p = 0.0004 (p = 0.002, after adjusting for multiple testing). This result is in tune with several recent experimental findings which suggest that ACCN1 may play an important role in the pathogenesis of MS. 相似文献
152.
Toscani T Moseriti A Dossena A Dall'Asta C Simoncini N Virgili R 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,855(2):242-248
A fast and sensitive method for the quantification of the mycotoxin ochratoxin A (OTA) in dry-cured meat products has been developed, which does not require a clean-up step, by HPLC with an alkaline mobile phase (pH 9.8). Validation procedures for specificity, trueness, ruggedness, stability, recovery and repeatability were performed. The decision limit (CC alpha) and the decision capability (CC beta) were calculated at 1.10 and 1.23 microg/kg, respectively. The procedure was applied to representative dehydration levels of dry-cured meat samples. 相似文献
153.
Leite ES Santana SR Hünenberger PH Freitas LC Longo RL 《Journal of molecular modeling》2007,13(9):1017-1025
The relative stabilities of the alkali [M ⊂ 222]+ cryptates (M = Na, K, Rb and Cs) in the gas phase and in solution (80:20 v/v methanol:water mixture) at 298 K, are computed
using a combination of ab initio quantum-chemical calculations (HF/6-31G and MP2/6-31+G*//HF/6-31+G*) and explicit-solvent
Monte Carlo free-energy simulations. The results suggest that the relative stabilities of the cryptates in solution are due
to a combination of steric effects (compression of large ions within the cryptand cavity), electronic effects (delocalization
of the ionic charge onto the cryptand atoms) and solvent effects (dominantly the ionic dessolvation penalty). Thus, the relative
stabilities in solution cannot be rationalized solely on the basis of a simple match or mismatch between the ionic radius
and the cryptand cavity size as has been suggested previously. For example, although the [K ⊂ 222]+ cryptate is found to be the most stable in solution, in agreement with experimental data, it is the [Na ⊂ 222]+ cryptate that is the most stable in the gas phase. The present results provide further support to the notion that the solvent
in which supramolecules are dissolved plays a key role in modulating molecular recognition processes.
Figure Alkali cryptates [M ⊂ 222]+ (M = Na, K, Rb and Cs) relative stabilities in gas and methanol:water solution: solvent effects
and molecular recognition
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
154.
Draisci R Montesissa C Santamaria B D'Ambrosio C Ferretti G Merlanti R Ferranti C De Liguoro M Cartoni C Pistarino E Ferrara L Tiso M Scaloni A Cosulich ME 《Proteomics》2007,7(17):3184-3193
Surveillance of illegal use of steroids hormones in cattle breeding is a key issue to preserve human health. To this purpose, an integrated approach has been developed for the analysis of plasma and urine from calves treated orally with a single dose of a combination of the androgenic steroids boldenone and boldione. A quantitative estimation of steroid hormones was obtained by LC-APCI-Q-MS/MS analysis of plasma and urine samples obtained at various times up to 36 and 24 h after treatment, respectively. These experiments demonstrated that boldione was never found, while boldenone alpha- and beta-epimers were detected in plasma and urine only within 2 and 24 h after drug administration, respectively. Parallel proteomic analysis of plasma samples was obtained by combined 2-DE, MALDI-TOF-MS and muLC-ESI-IT-MS/MS procedures. A specific protein, poorly represented in normal plasma samples collected before treatment, was found upregulated even 36 h after hormone treatment. Extensive mass mapping experiments proved this component as an N-terminal truncated form of apolipoprotein A1 (ApoA1), a protein involved in cholesterol transport. The expression profile of ApoA1 analysed by Western blot analysis confirmed a significant and time dependent increase of this ApoA1 fragment. Then, provided that further experiments performed with a growth-promoting schedule will confirm these preliminary findings, truncated ApoA1 may be proposed as a candidate biomarker for steroid boldenone and possibly other anabolic androgens misuse in cattle veal calves, when no traces of hormones are detectable in plasma or urine. 相似文献
155.
Pereira LA Báo SN Barbosa MS da Silva JL Felipe MS de Santana JM Mendes-Giannini MJ de Almeida Soares CM 《FEMS yeast research》2007,7(8):1381-1388
Paracoccidioides brasiliensis is an important fungal pathogen. The disease it causes, paracoccidioidomycosis (PCM), ranges from localized pulmonary infection to systemic processes that endanger the life of the patient. Paracoccidioides brasiliensis adhesion to host tissues contributes to its virulence, but we know relatively little about molecules and the molecular mechanisms governing fungal adhesion to mammalian cells. Triosephosphate isomerase (TPI: EC 5.3.1.1) of P. brasiliensis (PbTPI) is a fungal antigen characterized by microsequencing of peptides. The protein, which is predominantly expressed in the yeast parasitic phase, localizes at the cell wall and in the cytoplasmic compartment. TPI and the respective polyclonal antibody produced against this protein inhibited the interaction of P. brasiliensis to in vitro cultured epithelial cells. TPI binds preferentially to laminin, as determined by peptide inhibition assays. Collectively, these results suggest that TPI is required for interactions between P. brasiliensis and extracellular matrix molecules such as laminin and that this interaction may play an important role in the fungal adherence and invasion of host cells. 相似文献
156.
Santos LC Ramos EA Gurgel CA de Santana EJ Dos Santos JN 《Journal of molecular histology》2007,38(3):201-205
Objective Dental granulomas (DGs) and radicular cysts (RCs) are chronic periapical lesions frequently involving the jaws. Langerhans
cells (LCs) are dendritic cells responsible for the presentation of antigens to T lymphocytes. This study examined the expression
of LCs in DG and RCs by immunohistochemical staining.
Study Design Eighteen cases of DGs and 26 cases of RCs were analyzed using anti-CD1a marker.
Results CD1a-labeled LCs were observed in 11.1% of DGs and in 69.2% of RCs, showing a significant correlation (P < 0.0001; Fisher’s test). In DGs, LCs were only observed in granulation tissue, showing discrete immunostaining density.
In RCs, LCs exhibited both a round and a dendritic shape in all epithelial layers. Although a correlation was observed between
immunostaining density and epithelial thickness, as well as between immunostaining and inflammatory intensity, the differences
were not significant in radicular cysts.
Conclusion Langerhans cells provide important insight into the immunopathogenesis of chronic periapical lesions. 相似文献
157.
Averna M Stifanese R De Tullio R Salamino F Bertuccio M Pontremoli S Melloni E 《The FEBS journal》2007,274(23):6116-6127
Ca2+ loading of Jurkat and bovine aorta endothelium cells induces the degradation of the neuronal and endothelial nitric oxide synthases that are selectively expressed in these cell lines. For neuronal nitric oxide synthase, this process involves a conservative limited proteolysis without appreciable loss of catalytic activity. By contrast, endothelial nitic oxide synthase digestion proceeds through a parallel loss of protein and catalytic activity. The chaperone heat shock protein 90 (HSP90) is present in a large amount in Jurkat cells and at significantly lower levels in bovine aorta endothelium cells. The differing ratios of HSP90/nitric oxide synthase (NOS) occurring in the two cell types are responsible for the conservative or nonconservative digestion of NOS isozymes. Consistently, we demonstrate that, in the absence of Ca2+, HSP90 forms binary complexes with NOS isozymes or with calpain. When Ca2+ is present, a ternary complex containing the three proteins is produced. In this associated state, HSP90 and NOS forms are almost completely resistant to calpain digestion, probably due to a structural hindrance and a reduction in the catalytic efficiency of the protease. Thus, the recruitment of calpain in the HSP90-NOS complexes reduces the extent of the proteolysis of these two proteins. We have also observed that calpastatin competes with HSP90 for the binding of calpain in reconstructed systems. Digestion of the proteins present in the complexes can occur only when free active calpain is present in the system. This process can be visualized as a novel mechanism involving the association of NOS with HSP90 and the concomitant recruitment of active calpain in ternary complexes in which the proteolysis of both NOS isozymes and HSP90 is significantly reduced. 相似文献
158.
de Jesus Santana Mayla Barbosa-Júnior Sebastião Martins Dias Lana Laene Lima Silva Lázara Aline Simões da Silva Givanildo Zildo Fortini Evandro Alexandre Batista Diego Silva Otoni Wagner Campos da Costa Netto Antônio Paulino Rocha Diego Ismael 《In vitro cellular & developmental biology. Plant》2022,58(6):865-875
In Vitro Cellular & Developmental Biology - Plant - The aim of this study was to establish a system of in vitro germination and propagation of Guazuma ulmifolia Lam. microcuttings (Malvaceae).... 相似文献
159.
Marco Savioli Lorenzo Antonelli Gianfranco Bocchinfuso Francesca Cavalieri Rita Cimino Emanuela Gatto Ernesto Placidi Julio Raul Fernandez Masso Hilda Garay Perez Hector Santana Maribel Guerra-Vallespi Mariano Venanzi 《Journal of peptide science》2022,28(1):e3356
Synthetic therapeutic peptides (STP) are intensively studied as new-generation drugs, characterized by high purity, biocompatibility, selectivity and stereochemical control. However, most of the studies are focussed on the bioactivity of STP without considering how the formulation actually used for therapy administration could alter the physico-chemical properties of the active principle. The aggregation properties of a 20-mer STP (Ac-His-Ala-Arg-Ile-Lys-D-Pro-Thr-Phe-Arg-Arg-D-Leu-Lys-Trp-Lys-Tyr-Lys-Gly-Lys-Phe-Trp-NH2), showing antitumor activity, were investigated by optical spectroscopy and atomic force microscopy imaging, as itself (CIGB552) and in its therapeutic formulation (CIGB552TF). It has found that the therapeutic formulation deeply affects the aggregation properties of the investigated peptide and the morphology of the aggregates formed on mica by deposition of CIGB552 and CIGB552TF millimolar solutions. Molecular dynamics simulations studied the first steps of CIGB552 aggregation under physiological ionic strength conditions (NaCl 150 mM), showing that peptide oligomers, from dimers to tetramers, are preferentially formed in this environment. Interestingly, cell viability assays performed on H-460 cell lines indicate a major antiproliferative activity of the peptide in its therapeutic formulation with respect to the peptide aqueous solution. 相似文献
160.
Kathryn E. Stanchak Jessica H. Arbour Sharlene E. Santana 《Evolution; international journal of organic evolution》2019,73(8):1591-1603
Neomorphic, membrane‐associated skeletal rods are found in disparate vertebrate lineages, but their evolution is poorly understood. Here we show that one of these elements—the calcar of bats (Chiroptera)—is a skeletal novelty that has anatomically diversified. Comparisons of evolutionary models of calcar length and corresponding disparity‐through‐time analyses indicate that the calcar diversified early in the evolutionary history of Chiroptera, as bats phylogenetically diversified after evolving the capacity for flight. This interspecific variation in calcar length and its relative proportion to tibia and forearm length is of functional relevance to flight‐related behaviors. We also find that the calcar varies in its tissue composition among bats, which might affect its response to mechanical loading. We confirm the presence of a synovial joint at the articulation between the calcar and the calcaneus in some species, which suggests the calcar has a kinematic functional role. Collectively, this functionally relevant variation suggests that adaptive advantages provided by the calcar led to its anatomical diversification. Our results demonstrate that novel skeletal additions can become integrated into vertebrate body plans and subsequently evolve into a variety of forms, potentially impacting clade diversification by expanding the available morphological space into which organisms can evolve. 相似文献