304 research outputs found
Analysis of a spontaneous mutant and selected clones of cv. Italia (Vitis vinifera) by AFLP markers
A spontaneously formed mutant and selected clones (from clonal selection) of the table grape cv. Italia (Vitis vinifera) were evaluated with regard to the the possible use of molecular markers for grapevine clone differentiation. The identified off-type grapevine, which presents a mutated branch and a normal one on the same plant, removes any doubt as to its origin and allows a better evaluation of the suitability of molecular markers for the differentiation of grape clones. AFLPs were used as molecular markers because a large number of loci can be screened in a single assay, which is useful for any study on genotype relationships when a large number of bands (variables) is required. Different primer combinations (49) produced 3880 scorable AFLP bands but none showed any polymorphism among clones. Nevertheless it is suggested to use both AFLP and morphological markers for the differentiation of grapevine clones. The AFLPs would confirm the high level of DNA similarity among the suspected clones while morphological characters would allow to verify, through appropriate field experimental designs, the reliability of the phenotypic differences detected among grape clones.
Review on Antifungal Resistance Mechanisms in the Emerging Pathogen Candida auris.
Candida auris is an emerging multi-drug resistant yeast, that causes major issues regarding patient treatment and surface disinfection in hospitals. Indeed, an important proportion of C. auris strains isolated worldwide present a decreased sensitivity to multiple and sometimes even all available antifungals. Based on recent tentative breakpoints by the CDC, it appears that in the USA about 90, 30, and < 5% of isolates have been resistant to fluconazole, amphotericin B, and echinocandins, respectively. To date, this has lead to a low therapeutic success. Furthermore, C. auris is prone to cause outbreaks, especially since it can persist for weeks in a nosocomial environment and survive high-end disinfection procedures. In this review, we describe the molecular resistance mechanisms to antifungal drugs identified so far in C. auris and compare them to those previously discovered in other Candida species. Additionally, we examine the role that biofilm formation plays in the reduced antifungal sensitivity of this organism. Finally, we summarize the few insights on how this yeast survives on hospital surfaces and discuss the challenge it presents regarding nosocomial environment disinfection
Газификация промышленных отходов непрерывным лазерным излучением
Liposome-encapsulated corticosteroids have shown to exert strong beneficial effects in inflammatory diseases, such as arthritis and cancer. To extend the clinical applicability of these potent nanomedicines, the therapeutic effect of dexamethasone phosphate loaded long-circulating liposomes (LCL-DXP) was evaluated in animal models of multiple sclerosis (MS) and Crohn's disease (CD). In mice with experimental autoimmune encephalitis (EAE), a model for MS, treatment with LCL-DXP, but not free DXP, resulted in a decrease in disease activity when compared to PBS treated mice. In contrast, in mice with chronic DSS-induced colitis, a model for CD, treatment with LCL-DXP did not induce an improvement, but in fact worsened the fecal blood loss after treatment, indicating an aggravation of the disease. It is hypothesized that modulation of macrophage polarization towards a M2 phenotype underlies the efficacy of corticosteroid-based drug delivery systems, which is supported by the presented data. On the one hand, M1 polarized macrophages are part of the pathogenesis of MS; the modulation to M2-polarization by LCL-DXP is therefore beneficial. On the other hand, M1-polarized intestinal macrophages fulfill a protective and inflammation-suppressing role in intestinal homeostasis; changing their phenotype to M2 causes reduced protection to invading microorganisms, leading to a more severe intestinal inflammation. These findings therefore indicate that the interplay between the specific phenotype of macrophages and the specific inflammatory context of the inflammatory disease in question may be an important determining factor in the therapeutic applicability of liposomal corticosteroids in inflammatory disease
In vivo magnetic resonance spectroscopy in the brain of Cdkl5 null mice reveals a metabolic profile indicative of mitochondrial dysfunctions
Mutations in the X‐linked CDKL5 gene cause CDKL5 deficiency disorder (CDD), a severe neurodevelopmental condition mainly characterized by infantile epileptic encephalopathy, intellectual disability, and autistic features. The molecular mechanisms underlying the clinical symptoms remain largely unknown and the identification of reliable biomarkers in animal models will certainly contribute to increase our comprehension of CDD as well as to assess the efficacy of therapeutic strategies. Here, we used different Magnetic Resonance (MR) methods to disclose structural, functional, or metabolic signatures of Cdkl5 deficiency in the brain of adult mice. We found that loss of Cdkl5 does not cause cerebral atrophy but affects distinct brain areas, particularly the hippocampus. By in vivo proton‐MR spectroscopy (MRS), we revealed in the Cdkl5 null brain a metabolic dysregulation indicative of mitochondrial dysfunctions. Accordingly, we unveiled a significant reduction in ATP levels and a decrease in the expression of complex IV of mitochondrial electron transport chain. Conversely, the number of mitochondria appeared preserved. Importantly, we reported a significant defect in the activation of one of the major regulators of cellular energy balance, the adenosine monophosphate‐activated protein kinase (AMPK), that might contribute to the observed metabolic impairment and become an interesting therapeutic target for future preclinical trials. In conclusion, MRS revealed in the Cdkl5 null brain the presence of a metabolic dysregulation suggestive of a mitochondrial dysfunction that permitted to foster our comprehension of Cdkl5 deficiency and brought our interest towards targeting mitochondria as therapeutic strategy for CDD
Botanical and Genetic Identification Followed by Investigation of Chemical Composition and Biological Activities on the Scabiosa atropurpurea L. Stem from Tunisian Flora
Scarce information about the phenolic composition of Scabiosa atropurpurea L. is available, and no carotenoid compounds have been reported thus far. In this study the phenolic and carotenoid composition of this plant was both investigated and associated bioactivities were evaluated. Aiming to obtain extracts and volatile fractions of known medicinal plants to valorize them in the pharmaceutical or food industries, two techniques of extraction and five solvents were used to determine the biologically active compounds. Gas chromatography coupled to flame ionization and mass spectrometry and liquid chromatography coupled to photodiode array and atmospheric pressure chemical ionization/electrospray ionization mass spectrometry highlighted the presence of 15 volatiles, 19 phenolic, and 24 natural pigments in Scabiosa atropurpurea L. stem samples; among them, the most abundant were 1,8-cineole, chlorogenic acid, cynaroside, and lutein. Bioactivity was assessed by a set of in vitro tests checking for antioxidant, antibacterial, antifungal, and allelopathic (against Brassica oleracea L. and Lens culinaris Medik) effects. Scabiosa atropurpurea L. stem extracts presented a considerable antioxidant, antibacterial, and allelopathic potential, with less antifungal effectiveness. These results indicate that the volatile fractions and extracts from S. atropurpurea L. stem could be considered as a good source of bioactive agents, with possible applications in food-related, agriculture, and pharmaceutical fields. Genetic investigations showed 97% of similarity with Scabiosa tschiliensis, also called Japanese Scabiosa
High pressure phases in highly piezoelectric Pb(Zr0.52Ti0.48)O3
Two novel room-temperature phase transitions are observed, via synchrotron
x-ray diffraction and Raman spectroscopy, in the Pb(Zr0.52Ti0.48)O3 alloy under
hydrostatic pressures up to 16 GPa. A monoclinic (M)-to-rhombohedral (R1) phase
transition takes place around 2-3 GPa, while this R1 phase transforms into
another rhombohedral phase, R2, at about 6-7 GPa. First-principles calculations
assign the R3m and R3c symmetry to R1 and R2, respectively, and reveal that R2
acts as a pressure-induced structural bridge between the polar R3m and a
predicted antiferrodistortive R-3c phase.Comment: REVTeX, 4 pages with 3 figures embedded. Figs 1 and 3 in colo
JAB1 deletion in oligodendrocytes causes senescence-induced inflammation and neurodegeneration in mice
Oligodendrocytes are the primary target of demyelinating disorders, and progressive neurodegenerative changes may evolve in the CNS. DNA damage and oxidative stress are considered key pathogenic events, but the underlying molecular mechanisms remain unclear. Moreover, animal models do not fully recapitulate human diseases, complicating the path to effective treatments. Here we report that mice with cell-autonomous deletion of the nuclear COP9 signalosome component CSN5 (JAB1) in oligodendrocytes develop DNA damage and defective DNA repair in myelinating glial cells. Interestingly, oligodendrocytes lacking JAB1 expression underwent a senescence-like phenotype that fostered chronic inflammation and oxidative stress. These mutants developed progressive CNS demyelination, microglia inflammation, and neurodegeneration, with severe motor deficits and premature death. Notably, blocking microglia inflammation did not prevent neurodegeneration, whereas the deletion of p21CIP1 but not p16INK4a pathway ameliorated the disease. We suggest that senescence is key to sustaining neurodegeneration in demyelinating disorders and may be considered a potential therapeutic target
A facile method for the preparation of bifunctional Mn:ZnS/ZnS/Fe3O4 magnetic and fluorescent nanocrystals
Bifunctional magnetic and fluorescent core/shell/shell Mn:ZnS/ZnS/Fe3O4 nanocrystals were synthesized in a basic aqueous solution using 3-mercaptopropionic acid (MPA) as a capping ligand. The structural and optical properties of the heterostructures were characterized by X-ray diffraction (XRD), dynamic light scattering (DLS), transmission electron microscopy (TEM), UV–vis spectroscopy and photoluminescence (PL) spectroscopy. The PL spectra of Mn:ZnS/ZnS/Fe3O4 quantum dots (QDs) showed marked visible emission around 584 nm related to the 4T1 → 6A1 Mn2+ transition. The PL quantum yield (QY) and the remnant magnetization can be regulated by varying the thickness of the magnetic shell. The results showed that an increase in the thickness of the Fe3O4 magnetite layer around the Mn:ZnS/ZnS core reduced the PL QY but improved the magnetic properties of the composites. Nevertheless, a good compromise was achieved in order to maintain the dual modality of the nanocrystals, which may be promising candidates for various biological applications
Detrimental and protective action of microglial extracellular vesicles on myelin lesions: astrocyte involvement in remyelination failure
Microglia are highly plastic immune cells which exist in a continuum of activation states. By shaping the function of oligodendrocyte precursor cells (OPCs), the brain cells which differentiate to myelin-forming cells, microglia participate in both myelin injury and remyelination during multiple sclerosis. However, the mode(s) of action of microglia in supporting or inhibiting myelin repair is still largely unclear. Here, we analysed the effects of extracellular vesicles (EVs) produced in vitro by either pro-inflammatory or pro-regenerative microglia on OPCs at demyelinated lesions caused by lysolecithin injection in the mouse corpus callosum. Immunolabelling for myelin proteins and electron microscopy showed that EVs released by pro-inflammatory microglia blocked remyelination, whereas EVs produced by microglia co-cultured with immunosuppressive mesenchymal stem cells promoted OPC recruitment and myelin repair. The molecular mechanisms responsible for the harmful and beneficial EV actions were dissected in primary OPC cultures. By exposing OPCs, cultured either alone or with astrocytes, to inflammatory EVs, we observed a blockade of OPC maturation only in the presence of astrocytes, implicating these cells in remyelination failure. Biochemical fractionation revealed that astrocytes may be converted into harmful cells by the inflammatory EV cargo, as indicated by immunohistochemical and qPCR analyses, whereas surface lipid components of EVs promote OPC migration and/or differentiation, linking EV lipids to myelin repair. Although the mechanisms through which the lipid species enhance OPC maturation still remain to be fully defined, we provide the first demonstration that vesicular sphingosine 1 phosphate stimulates OPC migration, the first fundamental step in myelin repair. From this study, microglial EVs emerge as multimodal and multitarget signalling mediators able to influence both OPCs and astrocytes around myelin lesions, which may be exploited to develop novel approaches for myelin repair not only in multiple sclerosis, but also in neurological and neuropsychiatric diseases characterized by demyelination
Dose-Related Effects of Repeated ETC-216 (Recombinant Apolipoprotein A-IMilano/1-Palmitoyl-2-Oleoyl Phosphatidylcholine Complexes) Administrations on Rabbit Lipid-Rich Soft Plaques In Vivo Assessment by Intravascular Ultrasound and Magnetic Resonance Imaging
ObjectivesThis study sought to evaluate in vivo the minimal dose of apolipoprotein (apo) A-IMilano phospholipid complex (recombinant apoA-IMilano and 1-palmitoyl-2-oleoyl phosphatidylcholine complexes [ETC-216]) able to induce atherosclerosis regression in a rabbit model of lipid-rich plaques.BackgroundA single high dose of recombinant apoA-IMilano has promoted atherosclerosis regression in animal models. More recently, regression of atherosclerosis was achieved in coronary patients by repeated infusions of ETC-216.MethodsThirty-six rabbits underwent perivascular injury at both carotid arteries, followed by a 1.5% cholesterol diet. After 90 days, rabbits were randomly divided into 6 groups and treated 5 times with vehicle or ETC-216 at 5, 10, 20, 40, or 150 mg/kg dose every 4 days. Carotid plaque changes were evaluated in vivo by intravascular ultrasound (IVUS) and magnetic resonance imaging (MRI), performed before and at the end of treatments. Magnetic resonance imaging scans were also recorded after administration of the second dose for rabbits infused with vehicle 40 or 150 mg/kg.ResultsAtheroma volume in vehicle-treated rabbits increased dramatically between the first and the second IVUS analyses (+26.53%), whereas in ETC-216–treated animals, a reduced progression at the lower doses and a significant regression at the higher doses, up to −6.83%, was detected. Results obtained by MRI analysis correlated significantly with those at IVUS (r = 0.706; p < 0.0001). The MRI evaluations after the second infusion established that a significant regression was achieved with only 2 administrations of the highest dose.ConclusionsThese results confirm the efficacy of ETC-216 for atherosclerosis treatment and provide guidance for dose selection and frequency to obtain a significant reduction of plaque volume
- …