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111.
112.
Pramod Thakare Francesca Vasile Maura Vallaro Sonja Visentin Giulia Caron Emanuela Licandro Silvia Cauteruccio 《Journal of Pharmaceutical Analysis》2021,11(5):638
The first combined experimental and theoretical study on the ionization and lipophilic properties of peptide nucleic acid (PNA) derivatives, including eleven PNA monomers and two PNA decamers, is described. The acidity constants (pKa) of individual acidic and basic centers of PNA monomers were measured by automated potentiometric pH titrations in water/methanol solution, and these values were found to be in agreement with those obtained by MoKa software. These results indicate that single nucleobases do not change their pKa values when included in PNA monomers and oligomers. In addition, immobilized artificial membrane chromatography was employed to evaluate the lipophilic properties of PNA monomers and oligomers, which showed the PNA derivatives had poor affinity towards membrane phospholipids, and confirmed their scarce cell penetrating ability. Overall, our study not only is of potential relevance to evaluate the pharmacokinetic properties of PNA, but also constitutes a reliable basis to properly modify PNA to obtain mimics with enhanced cell penetration properties. 相似文献
113.
Gloria Griffante Shikha Chandel Daniela Ferrante Valeria Caneparo Daniela Capello Valentina Bettio Cinzia Borgogna Chiara Aleni Salvatore Esposito Andrea Sarro Alessandra Vasile Marco Comba Tommaso Testa Gianmarco Cotrupi Marco De Andrea Sara Bortoluzzi Marisa Gariglio 《Viruses》2021,13(11)
Longitudinal mapping of antibody-based SARS-CoV-2 immunity is critical for public health control of the pandemic and vaccine development. We performed a longitudinal analysis of the antibody-based immune response in a cohort of 100 COVID-19 individuals who were infected during the first wave of infection in northern Italy. The SARS-CoV-2 humoral response was tested using the COVID-SeroIndex, Kantaro Quantitative SARS-CoV-2 IgG Antibody RUO Kit (R&D Systems, Bio-Techne, Minneapolis, USA) and pseudotype-based neutralizing antibody assay. Using sequential serum samples collected from 100 COVID-19 recovered individuals from northern Italy—mostly with mild disease—at 2 and 10 months after their first positive PCR test, we show that 93% of them seroconverted at 2 months, with a geometric mean (GeoMean) half-maximal neutralization titer (NT50) of 387.9. Among the 35 unvaccinated subjects retested at 10 months, 7 resulted seronegative, with an 80% drop in seropositivity, while 28 showed decreased anti-receptor binding domain (RBD) and anti-spike (S) IgG titers, with a GeoMean NT50 neutralization titer dropping to 163.5. As an NT50 > 100 is known to confer protection from SARS-CoV-2 re-infection, our data show that the neutralizing activity elicited by the natural infection has lasted for at least 10 months in a large fraction of subjects. 相似文献
114.
Vasile Valeriu Lupu Ingrith Crenguta Miron Ancuta Lupu Mihaela Moscalu Elena Cristina Mitrofan Dragos Munteanu Alina Costina Luca 《Medicine》2021,100(47)
Gastroesophageal reflux disease occurs when gastric contents flow back into the esophagus and produce symptoms. Recurrent wheezing affects the quality of life for the patient and family. The association of gastroesophageal reflux with recurrent wheezing is suggested by different studies. The purpose of this study was to explore this relationship and to evaluate the outcome after appropriate treatment.A retrospective study on 85 children with recurrent wheezing, admitted in a pediatric gastroenterology regional center in Romania was performed. 24-hour continuous esophageal pH monitoring was used to evaluate the presence of gastroesophageal reflux and the results were interpreted using the Boix Ochoa score. All patients with positive score received treatment with proton pump inhibitors and they were evaluated again after 2 months.Gastroesophageal reflux was present in 71 children (83.5%), while 14 (16.5%) had a negative score, with a statistic significance (χ2 = 6.88, P = .0086, 95% confidence interval). After 2 months treatment with proton pump inhibitors, the Boix Ochoa score was still positive in 15 patients (21.13%).Recurrent wheezing is a solid reason for evaluating the presence of gastroesophageal reflux by 24-hour continuous esophageal pH-metry. Adequate treatment of gastroesophageal reflux solves also the recurrent wheezing in the majority of patients. 相似文献
115.
Ctlina Mihaela Grdinaru Adrian Alexandru erbnoiu Radu Muntean Bogdan Vasile erbnoiu 《Materials》2021,14(20)
The effects of the fly ash and of the sunflower stalks and corn cobs within a cement-matrix composite were studied under the aspects of density, compressive strength, splitting tensile strength, elasticity modulus, and resistance to repeated freeze-thaw cycles. In the research were developed 20 recipes of cement-based composite, including the reference composite. Fly ash was used as partial cement replacement (10, 20 and 30% by volume), and the vegetal aggregates made by corn cobs and sunflower stalks as partial replacement of the mineral aggregates (25 and 50% by volume). The study results revealed that a lightweight composite can be obtained with 50% of vegetal aggregates, and the fly ash, no matter its percentage, enhanced the compressive strength and splitting tensile strength of the compositions with 50% of sunflower aggregates and the freeze-thaw resistance of all compositions with sunflower stalks. 相似文献
116.
Laura Fiameni Ahmad Assi Ario Fahimi Bruno Valentim Karen Moreira Georgeta Predeanu Valerica Slvescu Bogdan . Vasile Adrian I. Nicoar Laura Borgese Gaia Boniardi Andrea Turolla Roberto Canziani Elza Bontempi 《RSC advances》2021,11(15):8927
The livestock sector is one of the most important sectors of the agricultural economy due to an increase in the demand for animal protein. This increase generates serious waste disposal concerns and has negative environmental consequences. Furthermore, the food production chain needs phosphorus (P), which is listed as a critical raw material due to its high demand and limited availability in Europe. Manure contains large amounts of P and other elements that may be recycled, in the frame of circular economy and “zero waste” principles, and reused as a by-product for fertilizer production and other applications. This paper focuses on the extraction and recovery of amorphous silica from rice husk poultry litter ash. Two different extraction procedures are proposed and compared, and the obtained silica is characterized. This work shows that amorphous silica can be recovered as an almost pure material rendering the residual ash free of P. It also addresses the possibility of more specific phosphorous extraction procedures via acid leaching.Rice husk poultry litter ash (RHPLA) is proposed as a valuable secondary source to recover phopshorus and amorphous silica in three steps. 相似文献
117.
Adrian Alexandru erbnoiu Ctlina Mihaela Grdinaru Nicanor Cimpoeu Dumitru Filipeanu Bogdan Vasile erbnoiu Nelu Cristian Chereche 《Materials》2021,14(23)
The use of plant ash as a sustainable cementitious material in concrete composition is a widely researched subject in the construction domain. A plant studied so far more for its thermal insulation properties, sunflower, was analyzed in this study with regard to its ash effects on the concrete composition. The present research aimed to analyze the effects of a 2.5%, 5%, 7.5%, 10%, 15%, 20%, or 30% volume replacement of cement by sunflower stalk ash (SA), a sustainable cementitious material, on the concrete compressive strength at 28 days and three months, the flexural and splitting tensile strengths, the resistance to repeated freeze–thaw cycles, and the resistance to chemical attack of hydrochloric acid. The elementary chemical composition of the SA and the composites was included also. According to the experimental results, SA decreased the values of the compressive and tensile strength of the concrete, but it improved the concrete behavior under repeated freeze–thaw cycles and under the action of hydrochloric acid. A percent of 10% of SA led to a much more pronounced development of compressive strength over time than conventional concrete (26.6% versus 12%). 相似文献
118.
Khan PM Correa RG Divlianska DB Peddibhotla S Sessions EH Magnuson G Brown B Suyama E Yuan H Mangravita-Novo A Vicchiarelli M Su Y Vasile S Smith LH Diaz PW Reed JC Roth GP 《ACS medicinal chemistry letters》2011,2(10):780-785
NOD1 (nucleotide-binding oligomerization domain 1) protein is a member of the NLR (NACHT and leucine rich repeat domain containing proteins) protein family, which plays a key role in innate immunity as a sensor of specific microbial components derived from bacterial peptidoglycans and induction of inflammatory responses. Mutations in NOD proteins have been associated with various inflammatory diseases that affect NF-κB (nuclear factor κB) activity, a major signaling pathway involved in apoptosis, inflammation, and immune response. A luciferase-based reporter gene assay was utilized in a high-throughput screening program conducted under the NIH-sponsored Molecular Libraries Probe Production Center Network program to identify the active scaffolds. Herein, we report the chemical synthesis, structure-activity relationship studies, downstream counterscreens, secondary assay data, and pharmacological profiling of the 2-aminobenzimidazole lead (compound 1c, ML130) as a potent and selective inhibitor of NOD1-induced NF-κB activation. 相似文献
119.
Inflammation is classically recognized as an essential step for the control of microbial invasion or tissue injury as well as for the maintenance of tissue homeostasis under a variety of noxious conditions. One of the most intriguing aspect of studying inflammation is the plurality of the inflammatory mediators that are continuously discovered (microRNAs, adipokines, inflammasomes and the danger signals, etc.) and their effects on target tissues. Several studies have demonstrated that inflammatory response represents the "common soil" of the multifactorial diseases, encompassing both chronic inflammatory rheumatic disorders and a wide variety of conditions including type 2 diabetes, cardiovascular and neurodegenerative diseases, obesity, cancer, asthma, and ageing. While the inflammatory response observed in the rheumatic disorders seems to be triggered by infection and injury, i.e. the main inducers of inflammation, in the other conditions mentioned it appears to be supported by tissue malfunction or homeostatic imbalance. In the present review, we discuss the data emerged from research on inflammatory mediators sustaining multifactorial diseases. 相似文献
120.
Andreica-Sandica B Panaete A Pascanu R Sarban C Andreica V 《Journal of gastrointestinal and liver diseases》2011,20(3):311-313
Helicobacter Pylori is considered to be the agent responsible for peptic ulcers and gastritis, and its eradication represents a main objective in the treatment of digestive diseases. We present the case report of a female patient diagnosed with chronic Helicobacter Pylori infection, where symptoms manifested after the patient was raped. In the context of psychological trauma, digestive manifestations such as ulcer and gastritis were identified, greatly exacerbated as compared with the endoscopic and histological aspect of the gastric mucosa. The patient simultaneously developed a complex psychiatric pathology. The association between Helicobacter Pylori chronic gastritis, somatization and trauma is discussed. 相似文献