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751.
Pierluigi Giampaolino Virginia Foreste Claudia Di Filippo Alessandra Gallo Antonio Mercorio Paolo Serafino Francesco Paolo Improda Paolo Verrazzo Giuseppe Zara Cira Buonfantino Maria Borgo Gaetano Riemma Chiara De Angelis Brunella Zizolfi Giuseppe Bifulco Luigi Della Corte 《International journal of molecular sciences》2021,22(4)
Polycystic ovary syndrome (PCOS) is a complex and heterogeneous endocrine disease. The hypothesis that alterations in the microbiome are involved in the genesis of PCOS has been postulated. Aim of this review is to summarize the available literature data about the relationship between microbiome and PCOS. A search on PubMed and Medline databases was performed from inception to November 20Most of evidence has focused on the connection of intestinal bacteria with sex hormones and insulin-resistance: while in the first case, a relationship with hyperandrogenism has been described, although it is still unclear, in the second one, chronic low-grade inflammation by activating the immune system, with increased production of proinflammatory cytokines which interfere with insulin receptor function, causing IR (Insulin Resistance)/hyperinsulinemia has been described, as well as the role of gastrointestinal hormones like Ghrelin and peptide YY (PYY), bile acids, interleukin-22 and Bacteroides vulgatus have been highlighted. The lower genital tract microbiome would be affected by changes in PCOS patients too. The therapeutic opportunities include probiotic, prebiotics and synbiotics, as well as fecal microbiota transplantation and the use of IL-22, to date only in animal models, as a possible future drug. Current evidence has shown the involvement of the gut microbiome in PCOS, seen how humanized mice receiving a fecal transplant from women with PCOS develop ovarian dysfunction, immune changes and insulin resistance and how it is capable of disrupting the secondary bile acid biosynthesis. A future therapeutic approach for PCOS may involve the human administration of IL-22 and bile acid glycodeoxycholic acid. 相似文献
752.
Ida Cariati Roberto Bonanni Mario Marini Anna Maria Rinaldi Beatrice Zarrilli Virginia Tancredi Claudio Frank Giovanna DArcangelo Marco Diociaiuti 《International journal of molecular sciences》2021,22(8)
Salmon calcitonin is a good model for studying amyloid behavior and neurotoxicity. Its slow aggregation rate allows the purification of low molecular weight prefibrillar oligomers, which are the most toxic species. It has been proposed that these species may cause amyloid pore formation in neuronal membranes through contact with negatively charged sialic acid residues of the ganglioside GM1. In particular, it has been proposed that an electrostatic interaction may be responsible for the initial contact between prefibrillar oligomers and GM1 contained in lipid rafts. Based on this evidence, the aim of our work was to investigate whether the neurotoxic action induced by calcitonin prefibrillar oligomers could be counteracted by treatment with neuraminidase, an enzyme that removes sialic acid residues from gangliosides. Therefore, we studied cell viability in HT22 cell lines and evaluated the effects on synaptic transmission and long-term potentiation by in vitro extracellular recordings in mouse hippocampal slices. Our results showed that treatment with neuraminidase alters the surface charges of lipid rafts, preventing interaction between the calcitonin prefibrillar oligomers and GM1, and suggesting that the enzyme, depending on the concentration used, may have a partial or total protective action in terms of cell survival and modulation of synaptic transmission. 相似文献
753.
Ruth Prieto-Montero Alejandro Prieto-Castaeda Alberto Katsumiti Miren P. Cajaraville Antonia R. Agarrabeitia María J. Ortiz Virginia Martínez-Martínez 《International journal of molecular sciences》2021,22(12)
BODIPY dyes have recently attracted attention as potential photosensitizers. In this work, commercial and novel photosensitizers (PSs) based on BODIPY chromophores (haloBODIPYs and orthogonal dimers strategically designed with intense bands in the blue, green or red region of the visible spectra and high singlet oxygen production) were covalently linked to mesoporous silica nanoparticles (MSNs) further functionalized with PEG and folic acid (FA). MSNs approximately 50 nm in size with different functional groups were synthesized to allow multiple alternatives of PS-PEG-FA decoration of their external surface. Different combinations varying the type of PS (commercial Rose Bengal, Thionine and Chlorine e6 or custom-made BODIPY-based), the linkage design, and the length of PEG are detailed. All the nanosystems were physicochemically characterized (morphology, diameter, size distribution and PS loaded amount) and photophysically studied (absorption capacity, fluorescence efficiency, and singlet oxygen production) in suspension. For the most promising PS-PEG-FA silica nanoplatforms, the biocompatibility in dark conditions and the phototoxicity under suitable irradiation wavelengths (blue, green, or red) at regulated light doses (10–15 J/cm2) were compared with PSs free in solution in HeLa cells in vitro. 相似文献
754.
755.
Loretta De Chiara Virginia Leiro-Fernandez Mar Rodríguez-Girondo Diana Valverde María Isabel Botana-Rial Alberto Fernndez-Villar 《International journal of molecular sciences》2020,21(23)
Different methodological approaches are available to assess DNA methylation biomarkers. In this study, we evaluated two sodium bisulfite conversion-dependent methods, namely pyrosequencing and methylation-specific qPCR (MS-qPCR), with the aim of measuring the closeness of agreement of methylation values between these two methods and its effect when setting a cut-off. Methylation of tumor suppressor gene p16/INK4A was evaluated in 80 lung cancer patients from which cytological lymph node samples were obtained. Cluster analyses were used to establish methylated and unmethylated groups for each method. Agreement and concordance between pyrosequencing and MS-qPCR was evaluated with Pearson’s correlation, Bland–Altman, Cohen’s kappa index and ROC curve analyses. Based on these analyses, cut-offs were derived for MS-qPCR. An acceptable correlation (Pearson’s R2 = 0.738) was found between pyrosequencing (PYRmean) and MS-qPCR (NMP; normalized methylation percentage), providing similar clinical results when categorizing data as binary using cluster analysis. Compared to pyrosequencing, MS-qPCR tended to underestimate methylation for values between 0 and 15%, while for methylation >30% overestimation was observed. The estimated cut-off for MS-qPCR data based on cluster analysis, kappa-index agreement and ROC curve analysis were much lower than that derived from pyrosequencing. In conclusion, our results indicate that independently of the approach used for estimating the cut-off, the methylation percentage obtained through MS-qPCR is lower than that calculated for pyrosequencing. These differences in data and therefore in the cut-off should be examined when using methylation biomarkers in the clinical practice. 相似文献
756.
Alexandra Virginia Bounegru Constantin Apetrei 《International journal of molecular sciences》2020,21(23)
Caffeic acid is one of the most important hydroxycinnamic acids found in various foods and plant products. It has multiple beneficial effects in the human body such as antioxidant, antibacterial, anti-inflammatory, and antineoplastic. Since overdoses of caffeic acid may have negative effects, the quality and quantity of this acid in foods, pharmaceuticals, food supplements, etc., needs to be accurately determined. The present paper analyzes the most representative scientific papers published mostly in the last 10 years which describe the development and characterization of voltamperometric sensors or biosensors based on carbon nanomaterials and/or enzyme commonly used for detecting caffeic acid and a series of methods which may improve the performance characteristics of such sensors. 相似文献
757.
María Virginia Candal Rosa Amalia Morales 《Polymer-Plastics Technology and Engineering》2013,52(4):376-383
The influence of the geometrical factors of plastic parts (shape factor, thickness, length/thickness ratio, and section changes) on the behavior of the cavity pressure during the injection process was studied. The instrumentation of injection molds was proposed, placing pressure transducers in the more critical zones of the parts. The evaluation of the molds was made using solid modelator and simulator software of the injection process with different polymers. The geometric factors determine the processing conditions to be used, the behavior of the cavity pressure during filling and postfilling phases, the cooling, and the dimensional stability of the part. 相似文献
758.
Virginia Martínez-Ruiz Pablo Lardelli-Claret Eladio Jiménez-Mejías Carmen Amezcua-Prieto José Juan Jiménez-Moleón Juan de Dios Luna del Castillo 《Accident; analysis and prevention》2013
A quasi-induced exposure approach was applied to the Spanish Register of Traffic Crashes to identify driver- and vehicle-related factors associated with the risk of causing a road crash involving a cyclist in Spain from 1993 to 2009. We analyzed 19,007 collisions between a bicycle and another vehicle in which only one of the drivers committed an infraction, and 13,540 records that included the group of non-infractor cyclists in the above collisions plus cyclists involved in single-bicycle crashes. Adjusted odds ratios were calculated for being responsible for each type of crash for each factor considered. Age from 10 to 19 years, male sex, alcohol or drug consumption and non-helmet use were cyclist-related variables associated with a higher risk of crash, whereas cycling more than 1 h increased only the risk of single crashes. Bicycles with brake defects and ridden by two occupants were also at higher risk of involvement in a crash, whereas light defects were associated only with collisions with another vehicle. For drivers of the other vehicle, age more than 60 years, alcohol, not using safety devices and nonprofessional drivers were at higher risk. The risk of colliding with a bicycle was higher for mopeds than for passenger cars. 相似文献
759.
Iván Ramos‐Diez Joaquín Navarro‐Hevia Roberto San Martín Fernández Virginia Díaz‐Gutiérrez Jorge Mongil‐Manso 《Water and Environment Journal》2016,30(1-2):119-127
Check dams play an important role worldwide in sediment retention, although their effectiveness is currently the subject of debate. In this study, 11 geometric models with their field methodology and equations are proposed to estimate the retained sediment quickly, easily and with a sufficient degree of approximation. The models were applied to a sample of check dams in the Saldaña badlands (Spain) in accordance with the shape of the valley to determine the volume of retained sediment and compare them with other widely used methods. Our geometric method gave lower volumes than topographic methods, but higher volumes than simple methods. This method is thus useful as a first approximation to estimate the sediment trapped by check dams and small silted dams, minimizing fieldwork, calculations and cost. Furthermore, it allows the selection of a better fit to the sediment wedge shape and higher accuracy than the simple methods used until now. 相似文献
760.