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961.
Maria Nicoletti Claudia Capodanno Cristian Gambarotti Elisa Fasoli 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(10):2293-2303
Background
The formation of bio-corona, due to adsorption of biomolecules onto carbon nanotubes (CNTs) surface in a physiological environment, may lead to a modified biological “identity” of CNTs, contributing to determination of their biocompatibility and toxicity.Methods
Multi-walled carbon nanotubes surfaces (f-MWCNTs) were modified attaching acid and basic chemical functions such as carboxyl (MWCNTs-COOH) and ammonium (MWCNTs-N) groups respectively. The investigation of interactions between f-MWCNTs and proteins present in biological fluids, like human plasma, was performed by electrophoretic separation (SDS-PAGE) and mass spectrometry analysis (nLC-MS/MS).Results
A total of 52 validated proteins was identified after incubation of f-MWCNTs in human plasma. 86% of them was present in bio-coronas formed on the surface of all f-MWCNTs and 29% has specifically interacted with only one type of f-MWCNTs.Conclusions
The evaluation of proteins primary structures, present in all bio-coronas, did not highlight any correlation between the chemical functionalization on MWCNTs and the content of acid, basic and hydrophobic amino acids. Despite this, many proteins of bio-corona, formed on all f-MWCNTs, were involved in the inhibitor activity of serine- or cysteine- endopeptidases, a molecular function completely unrevealed in the human plasma as control. Finally, the interaction with immune system's proteins and apolipoproteins has suggested a possible biocompatibility and a favored bio-distribution of tested f-MWCNTs.General significance
Considering the great potential of CNTs in the nanomedicine, a specific chemical functionalization onto MWCNTs surface could control the protein corona formation and the biocompatibility of nanomaterials. 相似文献962.
Héctor A. Vargas Sergio Rasmann Pamela Ramirez-Verdugo Cristian A. Villagra 《Neotropical Entomology》2018,47(1):62-68
Understanding the factors driving the diet breadth of phytophagous insects remains one of the main questions in ecological research. In this study we explored the diet breadth and plant-insect associations in the plume moth Lioptilodes friasi Vargas & Parra (Lepidoptera: Pterophoridae). This phytophagous insect was originally described in association with a single host species, Haplopappus foliosus (Asteraceae), a native shrub of the Chilean Mediterranean matorral. In order to address the breadth of host plant choice, we surveyed other Haplopappus species growing along the elevation gradient of central Chile from sea level to 2600 m. We were able to obtain L. friasi adults from five additional Haplopappus species: Haplopappus chrysantemifolius and Haplopappus decurrens from the coastal zone, Haplopappus multifolius and Haplopappus schumanii from the mid-elevation zone, and Haplopappus scrobiculatus at high elevation. Our results demonstrate that the genus-specialized endophagous herbivore L. friasi has a wider distribution and climatic tolerance than previously described. Its biogeographical range extends from the lowland coastal habitats up to the Andean subnival level. We propose that shared flower phenotypic traits such as morphology and chemical composition may have allowed the colonization of closely related Haplopappus species in central Chile, the expansion of which is limited by the harsh high elevation conditions. 相似文献
963.
A M Carcassi A Concu M Decandia D Licheri M Onnis M B Piras L Tocco 《Bollettino della Società italiana di biologia sperimentale》1979,55(22):2305-2309
Brief contraction of arm muscles affects respiratory ventilation either by increasing respiratory frequency or by increasing the instantaneous flow. Both these changes occur at a time subsequent to muscle contraction and can be attributed to a reflex mechanism originating from the muscles. 相似文献
964.
The protein kinase activity of a 10,000 g supernatant of purified human lymphocytes can be resolved by DEAE-cellulose chromatography into six protein kinase fractions: three of them phosphorylate casein preferentially, and three histones. The same procedure with the corresponding nuclear fraction yields only two casein kinases. All these fractions, except one casein kinase of the cytosol, have been studied with respect to protein and nucleotide specificity, effect of salts and of cyclic nucleotides, sedimentation, etc. The results obtained indicate that the enzyme fractions of the cytosol have distinct characteristics, suggesting that they are different protein kinases, and that the nuclear kinases are similar to the two main casein kinases of the cytosol. 相似文献
965.
Acute loss of intestinal CD4+ T cells is not predictive of simian immunodeficiency virus virulence 总被引:7,自引:0,他引:7
Pandrea IV Gautam R Ribeiro RM Brenchley JM Butler IF Pattison M Rasmussen T Marx PA Silvestri G Lackner AA Perelson AS Douek DC Veazey RS Apetrei C 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(5):3035-3046
The predictive value of acute gut-associated lymphoid tissue (GALT) CD4+ T cell depletion in lentiviral infections was assessed by comparing three animal models illustrative of the outcomes of SIV infection: pathogenic infection (SIVsmm infection of rhesus macaques (Rh)), persistent nonprogressive infection (SIVagm infection of African green monkeys (AGM)), and transient, controlled infection (SIVagm infection of Rh). Massive acute depletion of GALT CD4+ T cells was a common feature of acute SIV infection in all three models. The outcome of this mucosal CD4+ T cell depletion, however, differed substantially between the three models: in SIVsmm-infected Rh, the acute GALT CD4+ T cell depletion was persistent and continued with disease progression; in SIVagm, intestinal CD4+ T cells were partially restored during chronic infection in the context of normal levels of apoptosis and immune activation and absence of damage to the mucosal immunologic barrier; in SIVagm-infected Rh, complete control of viral replication resulted in restoration of the mucosal barrier and immune restoration. Therefore, our data support a revised paradigm wherein severe GALT CD4+ T cell depletion during acute pathogenic HIV and SIV infections of humans and Rh is necessary but neither sufficient nor predictive of disease progression, with levels of immune activation, proliferation and apoptosis being key factors involved in determining progression to AIDS. 相似文献
966.
Neovascularization and mast cells with tryptase activity increase simultaneously in human pterygium 总被引:1,自引:0,他引:1
Ribatti D Nico B Maxia C Longo V Murtas D Mangieri D Perra MT De Giorgis M Piras F Crivellato E Sirigu P 《Journal of cellular and molecular medicine》2007,11(3):585-589
Mast cells (MC) have been implicated in both normal and pathological angiogenesis, such as that in chronic inflammatory diseases and tumors. This assumption is partially supported by the close structural association between MC and blood vessels and the recruitment of these cells during tumor growth. MC release a number of angiogenic factors among which tryptase, a serine protease stored in MC granules, is one of the most active. In this study, we correlate the extent of angiogenesis with the number of tryptase-reactive MC in tissue fragments from pterygium and normal bulbar conjunctiva investigated by immunohistochemistry, using two murine monoclonal antibodies against the endothelial cell marker CD31 and the MC marker tryptase. Angiogenesis, measured as microvessel density, was highly correlated with MC tryptase-positive cell count in pterygium tissues. These results suggest that the characteristic neovascularization observed in pterygium may be sustained, at least in part, by MC angiogenic mediators, in particular tryptase. 相似文献
967.
968.
969.
Jing Li Guo‐Bo Chen Awais Rasheed Delin Li Kai Sonder Cristian Zavala Espinosa Jiankang Wang Denise E. Costich Patrick S. Schnable Sarah J. Hearne Huihui Li 《Molecular ecology》2019,28(15):3544-3560
Understanding the genomic basis of adaptation in maize is important for gene discovery and the improvement of breeding germplasm, but much remains a mystery in spite of significant population genetics and archaeological research. Identifying the signals underpinning adaptation are challenging as adaptation often coincided with genetic drift, and the base genomic diversity of the species in massive. In this study, tGBS technology was used to genotype 1,143 diverse maize accessions including landraces collected from 20 countries and elite breeding lines of tropical lowland, highland, subtropical/midaltitude and temperate ecological zones. Based on 355,442 high‐quality single nucleotide polymorphisms, 13 genomic regions were detected as being under selection using the bottom‐up searching strategy, EigenGWAS. Of the 13 selection regions, 10 were first reported, two were associated with environmental parameters via EnvGWAS, and 146 genes were enriched. Combining large‐scale genomic and ecological data in this diverse maize panel, our study supports a polygenic adaptation model of maize and offers a framework to enhance our understanding of both the mechanistic basis and the evolutionary consequences of maize domestication and adaptation. The regions identified here are promising candidates for further, targeted exploration to identify beneficial alleles and haplotypes for deployment in maize breeding. 相似文献
970.
Venturi Martina Piras Francesco Corrieri Federica Martinez Aguilar Ever Alexis Santoro Antonio 《Biodiversity and Conservation》2022,31(10):2315-2327
Biodiversity and Conservation - Traditional agro-silvo-pastoral systems are becoming each day more important, representing multifunctional systems that can contribute to the preservation of... 相似文献