1,721,046 research outputs found
Antitumoral Efficacy of Two Turmeric Extracts According to Different Extraction Methods in Hepatocellular Carcinoma Cell Lines
Full text linkCurcuminoids, bioactive molecules contained in turmeric, have been reported to exert anticancer effects in several human cancers, including hepatocellular carcinoma (HCC). However, the extraction method can significantly affect the structural characteristics of curcuminoids and their biological properties. On this basis, in the present study we investigated the content of curcuminoids and the anticancer activity of two turmeric powders extracted according two different methodologies: solvent extraction with ethyl acetate vs an ancient Indian extraction method of boiling of rhizomes in water followed by dehydration at the sun. Results obtained showed that extraction with ethyl acetate resulted in a significant recovery of curcuminoids and anticancer activity both in terms of cell cytotoxicity and migration/invasiveness inhibition in HCC cell lines, compared to common Indian practice. Overall these findings suggest that turmeric powders could have different efficacy, depending on the extraction method. This aspect should be taken into account when choosing the best product to be employed in the prevention and treatment of human diseases, including cancer
New analytical tools to investigate the role of protein glycosylation in Alzheimer’s disease
No full textImmobilized enzyme-based analytical tools in the -omics era: recent advances
No full textProtein analysis is a field under rapid development mainly thanks to technological advances which have granted miniaturization of analytical devices, automation and higher detection sensitivity. The interest in the field has paralleled the expansion of the -omics era, laying down the bases for the current applications in proteomics and glycomics. Advances in protein sample transformation prior to analysis have led to reduction of sample consumption and contamination, enhancing throughput. Within this context, and thanks to the availability of new high performing materials and technologies, increasingly more efficient and miniaturized enzyme-based analytical tools have been proposed to overcome shortcomings encountered in the in-solution enzymatic reactions (protein digestion and protein deglycosylation, for proteomics and glycomics, respectively). In this context, immobilized enzyme reactors (IMERs) and IMER-based platforms have been developed as promising approaches toward automation and higher analysis throughput. The scenario is in continuous development as underlined by thirty-four papers published in the last five years. This review encompasses recent advances in the design and operational set-ups of IMERs purposely developed for the analysis of proteins and glycoproteins. Recently developed dual IMERs, which integrate more than one processing step into a single IMER, and analytical platforms exploiting tandem IMERs are also reviewed and commented
Towards automation in protein digestion: Development of a monolithic trypsin immobilized reactor for highly efficient on-line digestion and analysis
Full text linkReducing experimental variability, limiting contamination and increasing automation are essential goals in the development of reliable analytical platforms for mass spectrometry (MS)-based proteomics. In this work novel trypsin-based monolithic immobilized enzyme reactors (tryp-IMERs), obtained by covalent immobilization on convective interaction media (CIMacTM) analytical columns (5 mm×5.2 mm I.D.), were developed. Notwithstanding the small dimensions, column format allowed the insertion in common high performance liquid chromatography (HPLC) systems, thus avoiding the use of expensive micro- or nano-platforms. Monolith pore diameter and surface chemistry were optimized to achieve high digestion efficiency even with high molecular weight proteins and to avoid protein/peptide adsorption, peak broadening and sample loss. A full characterization of the tryp-IMERs was undertaken to select the best protocol for preparation and type of trypsin. Optimization of the operational and storage conditions was carried out by an off-line approach. On-line studies were performed by setting a multidimensional analytical platform, which included the tryp-IMER, a trapping column, an analytical C4 column and a high resolution hybrid mass spectrometer (ESI-Q-TOF). In the optimized conditions rapid protein digestion (90±9 s), high protein coverage (≥60%) and high score values were achieved for five selected sample proteins (cytochrome c, myoglobin and albumins from different sources) differing in molecular size, isoelectric point and accessibility to cleavage sites as well as for a protein mixture of 200 ng. The best performing tryp-IMERs showed high sensitivity down to the pmole level. The platform also resulted suitable for the analysis of high-molecular weight proteins such as a pool of human immunoglobulins G (hIgG) and for the high molecular weight fraction of human plasma proteins, which were digested in less than two minutes to an extent similar to that achieved by overnight incubation in a classical in solution protocol. Finally, underestimated key procedural issues were also highlighted during the study. Such aspects are of general interest both for tryp-IMER users and tryp-IMER developers
A patent review of butyrylcholinesterase inhibitors and reactivators 2010–2017
No full textIntroduction: Butyrylcholinesterase (BuChE) has obtained a renewed interest as therapeutic target in Alzheimer’s disease (AD), when changes in BuChE activity and expression along disease progression were highlighted as well as correlation between BuChE levels and cognitive function. Areas covered: During the last eight years, fourteen patents on BuChE inhibitors (BuChEI) have been submitted. Only three of them relate to BuChE selective inhibitors, while four of them focus on multitarget inhibitors which address different key pathological factors other than BuChE. Two patents report on non-selective acetylcholinesterase (AChE)/BuChE inhibitors, while four patents deal with natural compounds and their derivatives. One patent relates to antitoxic agents to treat exposure to ChEI pesticides and nerve agents. Expert opinion: Increasing evidence supports BuChE as a more beneficial target in moderate-to-severe forms of AD in comparison to the well-known AChE. However, hitting a single pathological target is likely not sufficient to halt the disease progression. Therefore, patented BuChE inhibitors with a multifunctional profile may open new therapeutic avenues, since the additional activities could reinforce the therapeutic effects. Unfortunately, in vivo studies are limited and key parameters, such as ADMET data, are missing. This lack of information makes difficult to forecast the development of patented BuChEIs into effective drug candidates
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Structural and functional integrity of human serum albumin: Analytical approaches and clinical relevance in patients with liver cirrhosis
No full textHuman serum albumin (HSA) is the most abundant circulating plasma protein. Besides a significant contribution to the osmotic pressure, it is also involved in the fine regulation of many other physiological processes, including the balance of the redox state, the inflammatory and/or immunological responses, and the pharmacokinetic and pharmacodynamics of many drugs. Growing evidence suggests that HSA undergoes structural and functional damage in diseases characterized by an enhanced systemic inflammatory response and oxidative stress, as it occurs in chronic liver disease. Based on their clinical relevance, this review provides a summary of the most common post-translational modifications affecting HSA structural integrity and functions and their clinical relevance in the field of liver disease. The review also provides a critical description of the analytical approaches employed for the investigation of conformational alterations and the identification/quantitation of specific post-translational modifications affecting HSA. Finally, the analytical methods available for the assessment of two of the most clinically relevant non-oncotic properties of HSA, namely the binding capacity and the antioxidant activity, are critically reviewed. Among the available techniques particular attention is given to those proposed for the in vitro and in vivo investigation of structurally modified albumin
New insights into the altered binding capacity of pharmaceutical-grade human serum albumin: site-specific binding studies by induced circular dichroism spectroscopy
No full textThe ADMET profile of drugs is strongly affected by human serum albumin (HSA), due to its leading role as carrier of poorly soluble compounds in plasma; a critical assessment of the binding capacity of HSA and the evaluation of binding competition between drugs are therefore pivotal for a reliable pharmacokinetic and pharmacodynamic characterization. In clinical practice, a potential source of impairment in the binding properties of HSA is the use of octanoate and N-acetyltryptophan as stabilizers during the production of pharmaceutical-grade HSA for infusion (i-HSA), which is currently administered in the treatment of a growing range of pathological conditions. The peculiar sensitivity of circular dichroism (CD) spectroscopy towards the stereochemical features of high-affinity binding events is herein exploited to achieve a site-specific assessment of the effect of stabilizers on the binding properties of i-HSA. The binding affinity and capacity of fatty-acid-free HSA towards site-selective induced circular dichroism (ICD) markers for the three high-affinity binding sites of HSA was compared to that of i-HSA submitted to ultrafiltration and dialysis to remove both stabilizers. Results showed a considerable impairment of the binding capacity of i-HSA at site II and a relatively lower influence on the binding properties of site I. Ultrafiltration proved to be ineffective in depleting octanoate, while the proposed dialysis protocol, which involves a pH-induced reversible unfolding of the protein, resulted in a total clearance of both stabilizers, confirmed by the full restoration of the binding properties of HSA at all binding sites. The outcomes of this study proved that CD spectroscopy is a suitable technique to evaluate the binding properties of i-HSA, ensuring an assessment of the availability of the binding sites and the possibility of monitoring the clearance of stabilizers. Eventually, the proposed method for their depletion might constitute a connection bridge between albumin in vitro studies and its clinical applications
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