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Iron dyshomeostasis is implicated in Alzheimer's disease (AD) alongside β-amyloid and tau pathologies. Despite the recent discovery of ferroptosis, an iron-dependent form cell death, hitherto, in vivo evidence of ferroptosis in AD is lacking. The present study uniquely adopts an integrated multi-disciplinary approach, combining protein (Western blot) and elemental analysis (total reflection X-ray fluorescence) with metabolomics (1H nuclear magnetic resonance spectroscopy) to identify iron dyshomeostasis and ferroptosis, and possible novel interactions with metabolic dysfunction in age-matched male cognitively normal (CN) and AD post-mortem brain tissue (n = 7/group). Statistical analysis was used to compute differences between CN and AD, and to examine associations between proteins, elements and/or metabolites. Iron dyshomeostasis with elevated levels of ferritin, in the absence of increased elemental iron, was observed in AD. Moreover, AD was characterised by enhanced expression of the light-chain subunit of the cystine/glutamate transporter (xCT) and lipid peroxidation, reminiscent of ferroptosis, alongside an augmented excitatory glutamate to inhibitory GABA ratio. Protein, element and metabolite associations also greatly differed between CN and AD suggesting widespread metabolic dysregulation in AD. We demonstrate iron dyshomeostasis, upregulated xCT (impaired glutathione metabolism) and lipid peroxidation in AD, suggesting anti-ferroptotic therapies may be efficacious in AD. Chemical proteomics encompasses novel drug target deconvolution methods in which compound modification is not required. Herein we use Thermal Proteome Profiling, Functional Identification of Target by Expression Proteomics and multiplexed redox proteomics for deconvolution of auranofin targets to aid elucidation of its mechanisms of action. Auranofin (Ridaura®) was approved for treatment of rheumatoid arthritis in 1985. Because several clinical trials are currently ongoing to repurpose auranofin for cancer therapy, comprehensive characterization of its targets and effects in cancer cells is important. Together, our chemical proteomics tools confirmed thioredoxin reductase 1 (TXNRD1, EC1.8.1.9) as a main auranofin target, with perturbation of oxidoreductase pathways as the top mechanism of drug action. Additional indirect targets included NFKB2 and CHORDC1. Our comprehensive data can be used as a proteomic signature resource for further analyses of the effects of auranofin. Here we also assessed the orthogonality and complementarity of different chemical proteomics methods that can furnish invaluable mechanistic information and thus the approach can facilitate drug discovery efforts in general. Lignans are the bioactive constituents in Schisandra chinensis fruits. For the first time major representatives could directly be determined in plant extracts by using Supercritical Fluid Chromatography. Based on nine commercially available standards the method was developed, finally permitting their baseline separation in less than 10 min. The optimum setup showed to be a Viridis HSS C18 SB column, supercritical carbon dioxide and methanol. The compounds could be assigned in the extracts either at 210 nm or by MS, for which no modifications except of an additional sheath liquid (0.1 % acetic acid in methanol) were required. The determined lignan patterns were typical for S. chinensis, with schisandrol A being the most abundant compound, followed by schisandrin B or schisandrol B. As method validation results also complied well with the requirements the here presented method is definitely an interesting alternative to established techniques like UHPLC for the analysis of lignans in Schisandra chinensis. Bictegravir is a novel integrase strand transfer inhibitor, administrated in co-formulation with tenofovir alafenamide and emtricitabine (Biktarvy®), indicated in the management of HIV-1 infection in patients not previously treated with antiretroviral therapy. Bictegravir is highly bound to plasma proteins, and this significantly determines its clearance, solubility, and activity. These characteristics are crucial determinants of bictegravir penetration into human body compartments, as the central nervous system. We developed and validated UHPLC-MS/MS procedures to measure total and unbound bictegravir concentrations in plasma and cerebrospinal fluid. Simple protein precipitation with acetonitrile was implemented to prepare plasma and cerebrospinal fluid samples. Sample preparation was preceded by ultrafiltration for measuring unbound bictegravir concentrations. Chromatographic separations were achieved on an Acquity® UHPLC® BEHTM (2.1 × 100 mm id, 1.7 μm) reverse-phase C18 column using an isocratic mobile phase 2080 (v/v) water/acetonitrile with 0.1% formic. Bictegravir and its internal standard (bictegravir-15N d2) were detected by electrospray ionization mass spectrometry in positive and multiple reaction monitoring modes, using transitions of 450.2→289.2/145.4 and 453.2→289.2, respectively. Ultrafiltration procedures presented non-specific bindings of (8.6 ± 1.2) % for bictegravir in plasma and (26.6 ± 3.1) % for bictegravir in cerebrospinal fluid. Linearity was observed between (10.70-8560) μg/L, (1.07-856.0) μg/L for total and unbound bictegravir in plasma, and 0.107-26.75 μg/L for total and unbound bictegravir in cerebrospinal fluid. Imprecisions, absolute relative biases, normalized-matrix factors, and normalized-recoveries were ≤14.4%, ≤13.8%, (97.4-102.5) %, and (99.8-105.1) %, respectively. No significant interferences and carry-over were observed. The validated UHPLC-MS/MS procedures could be useful for pharmacokinetic and pharmacodynamic studies. A highly sensitive method was developed to quantitate the antileishmanial agent paromomycin in human plasma, with a lower limit of quantification of 5 ng/mL. Separation was achieved using an isocratic ion-pair ultra-high performance liquid chromatographic (UPLC) method with a minimal concentration of heptafluorobutyric acid, which was coupled through an electrospray ionization interface to a triple quadrupole - linear ion trap mass spectrometer for detection. The method was validated over a linear calibration range of 5 to 1000 ng/mL (r2≥0.997) with inter-assay accuracies and precisions within the internationally accepted criteria. Volumes of 50 μL of human K2EDTA plasma were processed by using a simple protein precipitation method with 40 μL 20 % trichloroacetic acid. A good performance was shown in terms of recovery (100 %), matrix effect (C.V. ≤ 12.0 %) and carry-over (≤17.5 % of the lower limit of quantitation). Paromomycin spiked to human plasma samples was stable for at least 24 h at room temperature, 6 h at 35 °C, and 104 days at -20 °C. Paromomycin adsorbs to glass containers at low concentrations, and therefore acidic conditions were used throughout the assay, in combination with polypropylene tubes and autosampler vials. The assay was successfully applied in a pharmacokinetic study in visceral leishmaniasis patients from Eastern Africa. Herbal medicine (HM) has been playing a pivotal role in maintaining human health since ancient times, and its therapeutic theory and clinical experience are the precious traditional medical knowledge reserves. As HM occupies an important position in its own right in global healthcare systems, robust quality assessment and control over its complex chemical composition was of great significance to assure its efficacy and safety. Over the past decades, the concept of HM chemical fingerprints aiming to obtain a comprehensive characterization of complex chemical matrices has become one of the most convincing tools for the quality assessment of HM. This review summarizes the recent analytical techniques used to generate HM chemical fingerprints, including chromatography, vibrational spectroscopy, nuclear magnetic resonance spectroscopy, and mass spectrometry. The advantages, drawbacks, and the application scope of each technology have been scrutinized in an attempt to better understand the data analysis. Furthermore, HM fingerprints together with multivariate and multiway chemometrics methods used for different application domains, such as similarity, exploratory, classification, and regression analysis, have also been discussed and illustrated with a few typical studies. The article provides a general picture and workflow of fingerprinting analyses that have been used for the quality assessment of HM. The progressive degeneration of nigrostriatal neurons leads to depletion of the neurotransmitter dopamine (DA) in Parkinson's disease (PD). The hydrophilicity of DA, hindering its cross of the Blood Brain Barrier, makes impossible its therapeutic administration. This work aims at investigating some physicochemical features of novel Solid Lipid Nanoparticles (SLN) intended to enhance DA brain delivery for PD patients by intranasal administration. For this aim, novel SLN were formulated in the presence of Glycol Chitosan (GCS), and it was found that SLN containing GCS and DA were smaller than DA-loaded SLN, endowed with a slightly positive zeta potential value and, remarkably, incorporated 81 % of the initial DA content. The formulated SLN were accurately characterized by Infrared Spectroscopy in Attenuated Total Reflectance mode (FT-IT/ATR) and Thermogravimetric Analysis (TGA) to highlight SLN solid-state properties as a preliminary step forward biological assay. Overall, in vitro characterization shows that SLN are promising for DA incorporation and stable from a thermal viewpoint. Further studies are in due course to test their potential for PD treatment. Radix Astragali is a famous Chinese traditional and folk medicine with a wide range of medicinal values in clinic. In this study, an analytical efficient strategy based on UHPLC-QQQ-MS/MS and UHPLC-LTQ-Orbitrap-MS/MS was established to explore and reveal the chemical transformations for Radix Astragali under different alkaline wash conditions for analytical sample preparation. Firstly, a rapid and sensitive UHPLC-QQQ-MS/MS method for the quantification of 14 main constituents in Radix Astragali has been developed and validated. Secondly, according to the standard substance comparison, accurate mass measurements, mass fragmentation behaviors and related literatures, a total of 102 components have been screened and identified using UHPLC-LTQ-Orbitrap method. Among them, 47 compounds are saponins, and the other 55 are flavonoids. Consequently, there were two chemical transformations including hydrolysis and degradation observed when Radix Astragali was treated with alkali. Besides, hydrolysis of glycosides and acetyl played a considerably important role in the process of sample preparation. It has been proved that 10 % ammonia could relatively guarantee the high content of astragaloside IV and avoid the over-degradation of most chemical ingredients in Radix Astragali. In conclusion, this work would provide a scientific and practical method for quality control of Radix Astragali as well as its compound preparations. V.Bisphenol A, a very widespread environmental pollutant and endocrine disruptor compound, can interact with several steroid receptors, particularly with estrogen ones. Oltipraz ic50 In different studies, it has observed that the endocrine disruption during critical periods of development can trigger alterations in the immune response during the adult life. Male Wistar rats were exposed indirectly to BPA at a dose of 250 μg/kg day during the perinatal period (from day 5 of pregnancy until day 21 postnatal), At the 60 days of age, the adulthood, animals were infected with larvated eggs of the Toxocara canis, and were sacrificed at 7 days post-infection. Parasitic loads in the lung and in the liver were analyzed by artificial digestion. Furthermore, immune cell subpopulations (macrophages, NK cells, Tγδ, total T cells, T helper, T cytotoxic, and B lymphocytes) present in spleen, peripheral and mesenteric lymph nodes were analyzed by flow cytometry. The expression of Th1 and Th2 cytokines at the splenic level was determined by real-time quantitative PCR.

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