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排序方式: 共有4287条查询结果,搜索用时 15 毫秒
991.
Chiara Stefani Antonella Sangalli Elena Locatelli Tania Federico Giovanni Malerba Maria Grazia Romanelli Gustavo Adolfo Argaaraz Bosco Christiano Maciel Da Silva Alberto Jose Duarte Da Silva Jorge Casseb Enrique Roberto Argaaraz Alessandra Ruggiero Donato Zipeto 《International journal of molecular sciences》2022,23(23)
HIV-1 infection in the absence of treatment results in progression toward AIDS. Host genetic factors play a role in HIV-1 pathogenesis, but complete knowledge is not yet available. Since less-expressed HLA-C variants are associated with poor HIV-1 control and unstable HLA-C variants are associated with higher HIV-1 infectivity, we investigated whether there was a correlation between the different stages of HIV-1 progression and the presence of specific HLA-C allotypes. HLA-C genotyping was performed using allele-specific PCR by analyzing a treatment-naïve cohort of 96 HIV-1-infected patients from multicentric cohorts in the USA, Canada, and Brazil. HIV-1-positive subjects were classified according to their different disease progression status as progressors (Ps, n = 48), long-term non-progressors (LTNPs, n = 37), and elite controllers (ECs, n = 11). HLA-C variants were classified as stable or unstable according to their binding stability to β2-microglobulin/peptide complex. Our results showed a significant correlation between rapid progression to AIDS and the presence of two or one unstable HLA-C variants (p-value: 0.0078, p-value: 0.0143, respectively). These findings strongly suggest a link between unstable HLA-C variants both at genotype and at allele levels and rapid progression to AIDS. This work provides further insights into the impact of host genetic factors on AIDS progression. 相似文献
992.
Paola Piscopo Valeria Manzini Roberto Rivabene Alessio Crestini Loredana Le Pera Elisabetta Pizzi Caterina Veroni Giuseppina Talarico Martina Peconi Anna Elisa Castellano Carmelo DAlessio Giuseppe Bruno Massimo Corbo Nicola Vanacore Eleonora Lacorte 《International journal of molecular sciences》2022,23(21)
The most frequently used biomarkers to support the diagnosis of Alzheimer’s Disease (AD) are Aβ42, total-Tau, and phospho-tau protein levels in CSF. Moreover, magnetic resonance imaging is used to assess hippocampal atrophy, 18F-FDG PET to identify abnormal brain metabolism, and PET imaging for amyloid deposition. These tests are rather complex and invasive and not easily applicable to clinical practice. Circulating non-coding RNAs, which are inherently stable and easy to manage, have been reported as promising biomarkers for central nervous system conditions. Recently, circular RNAs (circRNAs) as a novel class of ncRNAs have gained attention. We carried out a pilot study on five participants with AD and five healthy controls (HC) investigating circRNAs by Arraystar Human Circular RNA Microarray V2.0. Among them, 26 circRNAs were differentially expressed (FC ≥ 1.5, p < 0.05) in participants with AD compared to HC. From a top 10 of differentially expressed circRNAs, a validation study was carried out on four up-regulated (hsa_circRNA_050263, hsa_circRNA_403959, hsa_circRNA_003022, hsa_circRNA_100837) and two down-regulated (hsa_circRNA_102049, hsa_circRNA_102619) circRNAs in a larger population. Moreover, five subjects with mild cognitive impairment (MCI) were investigated. The analysis confirmed the upregulation of hsa_circRNA_050263, hsa_circRNA_403959, and hsa_circRNA_003022 both in subjects with AD and in MCI compared to HCs. We also investigated all microRNAs potentially interacting with the studied circRNAs. The GO enrichment analysis shows they are involved in the development of the nervous system, and in the cellular response to nerve growth factor stimuli, protein phosphorylation, apoptotic processes, and inflammation pathways, all of which are processes related to the pathology of AD. 相似文献
993.
Federico Colombo Andrea Pagano Stefano Sangiorgio Anca Macovei Alma Balestrazzi Fabrizio Araniti Roberto Pilu 《International journal of molecular sciences》2023,24(1)
Phytic acid (PA) is a strong anti-nutritional factor with a key antioxidant role in countering reactive oxygen species. Despite the potential benefits of low phytic acid (lpa) mutants, the reduction of PA causes pleiotropic effects, e.g., reduced seed germination and viability loss related to seed ageing. The current study evaluated a historical series of naturally aged seeds and showed that lpa1-1 seeds aged faster as compared to wildtype. To mimic natural ageing, the present study set up accelerated ageing treatments at different temperatures. It was found that incubating the seeds at 57 °C for 24 h, the wildtype germinated at 82.4% and lpa1-1 at 40%. The current study also hypothesized two possible solutions to overcome these problems: (1) Classical breeding was used to constitute synthetic populations carrying the lpa1-1 mutation, with genes pushing anthocyanin accumulation in the embryo (R-navajo allele). The outcome showed that the presence of R-navajo in the lpa1-1 genotype was not able to improve the germinability (−20%), but this approach could be useful to improve the germinability in non-mutant genotypes (+17%). (2) In addition, hydropriming was tested on lpa1-1 and wildtype seeds, and germination was improved by 20% in lpa1-1, suggesting a positive role of seed priming in restoring germination. Moreover, the data highlighted metabolic differences in the metabolome before and after hydropriming treatment, suggesting that the differences in germination could also be mediated by differences in the metabolic composition induced by the mutation. 相似文献
994.
Amalia Luce Angela Lombardi Carmela Ferri Silvia Zappavigna Madhura S. Tathode Amanda K. Miles David J. Boocock Jayakumar Vadakekolathu Marco Bocchetti Roberto Alfano Rossella Sperlongano Angela Ragone Luigi Sapio Vincenzo Desiderio Silvio Naviglio Tarik Regad Michele Caraglia 《International journal of molecular sciences》2023,24(1)
995.
996.
Carlos Jarava-Barrera Alejandro Parra Sergio Quesada Sergio Orgaz-Gordillo Roberto Fernández de la Pradilla Alma Viso Javier Teresa Inés Alonso Mariola Tortosa 《Advanced Synthesis \u0026amp; Catalysis》2024,366(4):768-773
An array of enantioenriched vinyl boronates bearing an allylic carbonate moiety have been prepared through selective hydroboration of propargyl carbonates. Treatment of these vinyl boronates with TBAF in THF affords enantioenriched 1,3-disubstituted allenes through a novel 1,2-anti elimination in good yields and high enantiospecificities. 相似文献
997.
998.
Rauch G Bertolini S Sacile R Giacomini M Ruggiero C 《IEEE transactions on nanobioscience》2011,10(3):152-159
A new method to analyze single ionic channel current conduction is presented. It is based on an automatic classification by K-means algorithm and on the concept of information entropy. This method is used to study the conductance of multistate ion current jumps induced by tetanus toxin in planar lipid bilayers. A comparison is presented with the widely used Gaussian best fit approach, whose main drawback is the fact that it is based on the manual choice of the base line and of meaningful fragments of current signal. On the contrary, the proposed method is able to automatically process a great amount of information and to remove spurious transitions and multichannels. The number of levels and their amplitudes do not have to be known a priori. In this way the presented method is able to produce a reliable evaluation of the conductance levels and their characteristic parameters in a short time. 相似文献
999.
We present a simple model and carry out simulations to investigate the dynamics of mixtures of granular material within a
rotating drum. On the basis of the commonly held belief (supported by considerable experimental evidence) that segregation
is due to motion of particles on the active layer, the bulk playing little or no role, we introduce a 2d lattice gas model
which takes into account the rotational frequency, frictional forces, and the gravitational field, and represents segregation
tendencies via activated effective grain-grain interactions. Our results include the onset of segregation perpendicular to
the drum axis, the appearance and subsequent coarsening of bands and peculiarities of the effects of periodic modulation of
the drum. Observed effects such as the segregation of rougher (smoother) particles into the bellies (necks) of the modulation
are reproduced by our simulation.
Received: 30 March 2000 相似文献
1000.
Megumi Kawasaki Roberto B. Figueiredo Cheng Xu Terence G. Langdon 《Metallurgical and Materials Transactions A》2007,38(9):1891-1898
Conventional superplasticity is generally achieved in metals having grain sizes in the range of ∼2 to 5 μm, but processing
by equal-channel angular pressing (ECAP) provides the opportunity of introducing exceptional grain refinement and producing
materials with ultrafine grain sizes in the submicrometer range. These materials have the potential for exhibiting excellent
superplastic properties when tested in tension at elevated temperatures and examples are presented for representative aluminum
and magnesium alloys. When these ultrafine-grained materials deform in superplasticity, internal cavities develop as in conventional
superplastic alloys. An example is presented for an aluminum-based alloy, and it is shown that the cavity growth processes
are also similar to those in conventional alloys.
This article is based on a presentation made in the symposium entitled “Ultrafine-Grained Materials: From Basics to Application”,
which occurred September 25–27, 2006, in Kloster Irsee, Germany. 相似文献