17 research outputs found
Case Report Neuroendocrine Cell Carcinoma of Unknown Primary Arising in Long Standing History of Multiple Sclerosis
Multiple sclerosis (MS) is a chronic autoimmune disease that targets myelinated axons in the central nervous system (CNS). Cancer of unknown primary site (CUP) is a well-recognised clinical disorder, accounting for 3-5% of all malignant epithelial tumors. CUP is clinically characterised as an aggressive disease with early dissemination. Studies of cancer risk in MS patients have shown inconsistent findings. An increased risk of malignancy in patients with MS has been suggested, but recently serious questions have been raised regarding this association. Use of disease-modifying therapies might contribute to an increased cancer risk in selected MS patients. The concurrence of MS and CUP is exceptionally rare. Here we describe the case of a neuroendocrine carcinoma of unknown primary diagnosed in a male patient with a nine-year history of MS. The discussion includes data from all available population-based register studies with estimates of certain malignancies in patients with MS
Traditional uses, phytochemistry and pharmacology of Chios mastic gum (Pistacia lentiscus var. Chia, Anacardiaceae): A review
Ethnopharmacological relevance
Chios mastic gum constitutes a unique Greek product, produced exclusively in the southern part of the island of Chios. References about its use from local populations for the treatment of gastrointestinal disorders or as a cosmetic agent can even be encountered in ancient texts of Galen, Theophrastus and Dioscorides. Nowadays, this versatile resin has been rediscovered, not only as a traditional remedy and aromatic agent, but as a potent phytotherapeutic product with various biological properties.
Aim of the study: The aim of this study is to quote the summation of the ethnopharmacology, phytochemical profile and pharmacological properties of the resin of Pistacia lentiscus var. Chia and thus provide the scientific community with a summary of the research conducted so far. Furthermore, perspectives and uses are being discussed and studied so as to broaden the field of its applications.
Materials and methods
A comprehensive review of the literature on Pistacia lentiscus var. Chia was performed using as resources scientific databases such as Scopus, Sciencedirect, Pubmed and Web of science, studies and traditional books provided by the Chios Mastiha Growers Association as well as PhD and Master’ s theses.
Results
Chios mastic gum has been used as a traditional medicine over the last 2500 years. More than 120 chemical compounds have been identified in the resin and the major components are a natural polymer, acidic and neutral triterpenes and volatile secondary metabolites. Several plant extracts and compounds have been studied for their antibacterial, anti-inflammatory, antioxidant, anti-ulcer, anti-diabetic, cardioprotective and anti-cancer properties in vitro and in vivo. Clinical interventions and trials have also showed the therapeutic potential of Chios mastic gum. In 2015 Pistacia lentiscus L., resin (mastic) was recognized as a herbal medicinal product with traditional use by the European Medicines Agency (EMA) with two therapeutic indications (mild dyspeptic disorders & skin inflammation/healing of minor wounds). Over the last years, Chios mastic gum is widely involved in medicinal products, food supplements and cosmetics and has become object of study, also in the field of Pharmacotechnology.
Conclusions
Chios mastic's beneficial properties have been demonstrated in the treatment of gastrointestinal disorders, wound healing, skin inflammations, plasma lipid and blood sugar reduction and oral care. These properties are attributed to triterpenes and volatile compounds. However, because of the resin's chemical complexity and the lack of commercial standards for its main compounds, there is a notable gap in literature concerning the biological evaluation of CMG's isolated components. Therefore, future research should focus on the development of efficient extraction, isolation and analysis techniques in order to unravel CMG's full pharmacological potential
Functional consequences of Peroxiredoxin-5 gene inactivation in the mouse
Peroxiredoxins (Prdxs) are a superfamily of peroxidases widely distributed among prokaryotes and eukaryotes. Prdx5 is ubiquitously expressed in tissues and its role as cytoprotective antioxidant enzyme as well as modulator of redox signaling have been largely reported in vitro. The goal of this work was to study in vivo Prdx5 functions through the generation of transgenic mice in which Prdx5 gene was disrupted using gene trapping strategy. Prdx5 knockout (Prdx5-/-) mice are viable and fertile. The vulnerability of Prdx5-/- mice to lipopolysaccharide (LPS) in vivo was examined. Our results show that Prdx5-/- mice mortality is significantly higher after intraperitoneal injection of 20 mg/kg of LPS compared to the Prdx5+/+. A proteomic analysis of proteins extracted from primary culture of Prdx5-/- and Prdx5+/+ phagocytes, exposed for 24 hours to 1 μg/ml LPS revealed that proteins related to inflammation, cancer, apoptosis and redox state regulation were altered in the Prdx5-/- phagocytes. Also, 41 % of old Prdx5-/- mice developed significantly more tumors compared to 16 % of Prdx5+/+ animals, suggesting that Prdx5 protein is involved in tumor suppression in vivo. Most of the tumors are characterized as lymphoma and hepatocarcinoma. Moreover, the Akt/PTEN signaling pathway in Prdx5-/- MEF cells was investigated, showing that phosphorylation of Akt is higher in Prdx5-/- cells exposed to H2O2. Finally, the consequences of Prdx5 gene inactivation was examined in the central nervous system. Prdx5-/- mice present significantly less motor coordination and a tendency of higher anxiety. Additionally, absence of Prdx5 is linked to glial cell proliferation in hippocampus, suggesting a role in neuroinflammation. Altogether, our results suggest that Prdx5 may play important roles in inflammation and in tumor suppression.(SC - Sciences) -- UCL, 201
A Content and Sentiment Analysis of Greek Tweets during the Pandemic
During the time of the coronavirus, strict prevention policies, social distancing, and limited contact with others were enforced in Greece. As a result, Twitter and other social media became an important place of interaction, and conversation became online. The aim of this study is to examine Twitter discussions around COVID-19 in Greece. Twitter was chosen because of the critical role it played during the global health crisis. Tweets were recorded over four time periods. NodeXL Pro was used to identify word pairs, create semantic networks, and analyze them. A lexicon-based sentiment analysis was also performed. The main topics of conversation were extracted. “New cases” are heavily discussed throughout, showing fear of transmission of the virus in the community. Mood analysis showed fluctuations in mood over time. Positive emotions weakened and negative emotions increased. Fear is the dominant sentiment. Timely knowledge of people’s sentiment can be valuable for government agencies to develop efficient strategies to better manage the situation and use efficient communication guidelines in Twitter to disseminate accurate, reliable information and control panic
Multiple roles of peroxiredoxins in inflammation.
Inflammation is a pathophysiological response to infection or tissue damage during which high levels of reactive oxygen and nitrogen species are produced by phagocytes to kill microorganisms. Reactive oxygen and nitrogen species serve also in the complex regulation of inflammatory processes. Recently, it has been proposed that peroxiredoxins may play key roles in innate immunity and inflammation. Indeed, peroxiredoxins are evolutionarily conserved peroxidases able to reduce, with high rate constants, hydrogen peroxide, alkyl hydroperoxides and peroxynitrite which are generated during inflammation. In this minireview, we point out different possible roles of peroxiredoxins during inflammatory processes such as cytoprotective enzymes against oxidative stress, modulators of redox signaling, and extracellular pathogen- or damage-associated molecular patterns. A better understanding of peroxiredoxin functions in inflammation could lead to the discovery of new therapeutic targets
An Approach towards Investigating Factors Affecting Intention to Book a Hotel Room through Social Media
Today, social media have become a major trend, and consumers are engaging more and more in the social media platforms used by hotels. This does not mean that they book a hotel room via social media, as the booking process is a complex one. The paper investigates the factors that affect users’ intention to book a hotel room using social media applications. The recent enforcement of General Data Protection Regulation (GDPR) in the European Union and California Consumer Privacy Act (CCPA) in California may have an impact on consumers’ behavior. To investigate this further, the study integrates into a model the following constructs: Perceived ease of use, perceived usefulness, trust in online hoteliers, social media use, and permission-based-acceptance. The survey was conducted on Greek users of social media. An online questionnaire was used for data collection. The conceptual model was tested using Structural Equation Modeling (SEM) analysis. The study identified four factors that directly or indirectly influence consumers’ intention to book hotel rooms through social media. Usefulness directly affects intention to book online. Permission-based acceptance plays a core role in the model. Both constructs trust in online hoteliers and social media use, and have a direct positive effect on permission-based acceptance, whereas permission-based acceptance has a direct positive influence on intention to book through social media. The validated model stretches the need for hoteliers to obtain permission from consumers in carrying out their marketing activities. It is important for hotel owners, managers, and social media specialists to keep consumers in mind, offer them useful information and services, and have a trustworthy behavior in order to boost bookings through social media
Protein and cell wall polysaccharide carbonyl determination by a neutral pH 2,4-dinitrophenylhydrazine-based photometric assay
A new 2,4-dinitrophenylhydrazine (DNPH)-based photometric assay is developed for the quantification of carbonyls in protein samples from any biological source by protein carbonyl-DNPH hydrazone formation at acidic pH in the presence of denaturing urea, and subsequent hydrazone solubilization in the presence of SDS and stabilization from acid hydrolysis at pH 7.0. At this neutral (ntr) pH, interfering unreacted DNPH is uncharged and its thus increased hydrophobicity permits its 100% effective removal from the solubilizate with ethyl acetate/hexane wash. The ntrDNPH assay is more reliable and sensitive than the standard (std) DNPH photometric assay because it eliminates its main limitations: (i) interfering unreacted DNPH (pKa 1.55) that is nonspecifically bound to the TCA (pKa 0.7)-protein pellet is not effectively removed after wash with EtOH: ethyl acetate because it is positively charged, (ii) acid (TCA-induced) hydrolysis of the protein carbonyl-DNPH hydrazone, (iii) sample protein concentration re-determination, (iv) loss of sample acid (TCA)-soluble proteins, (v) DNA interference, and (vi) requires high protein quantity samples (≥ 1 mg). Considering ntrDNPH assay’s very low protein limit (1 µg), its cumulative and functional sensitivities are 2600- and 2000-fold higher than those of the stdDNPH assay, respectively. The present study elucidates the DNA interference mechanism on the stdDNPH assay, and also develops a standardized protocol for sample protein treatment and fractionation (into cytoplasmic/aqueous, membrane/lipid-bound, and histone/DNA-bound proteins; see Supplement section V) in order to ensure reproducible carbonyl determination on defined cell protein fractions, and to eliminate assay interference from protein samples containing (i) Cys sulfenic acid groups (via their neutralization with dithiothreitol), and (ii) DNA (via its removal by streptomycin sulfate precipitation). Lastly, the ntrDNPH assay determines carbonyl groups on cell wall polysaccharides, thus paving the way on studies to investigate cell walls acting as antioxidant defense in plants, fungi, bacteria and lichens. Keywords: Photometric method, 2,4-dinitrophenylhydrazine, Protein carbonyls, Cell wall polysaccharide carbonyls, Oxidative stress, DNA interference, Protein fractionatio
Neuroendocrine Cell Carcinoma of Unknown Primary Arising in Long Standing History of Multiple Sclerosis
Multiple sclerosis (MS) is a chronic autoimmune disease that targets myelinated axons in the central nervous system (CNS). Cancer of unknown primary site (CUP) is a well-recognised clinical disorder, accounting for 3–5% of all malignant epithelial tumors. CUP is clinically characterised as an aggressive disease with early dissemination. Studies of cancer risk in MS patients have shown inconsistent findings. An increased risk of malignancy in patients with MS has been suggested, but recently serious questions have been raised regarding this association. Use of disease-modifying therapies might contribute to an increased cancer risk in selected MS patients. The concurrence of MS and CUP is exceptionally rare. Here we describe the case of a neuroendocrine carcinoma of unknown primary diagnosed in a male patient with a nine-year history of MS. The discussion includes data from all available population-based register studies with estimates of certain malignancies in patients with MS
Protein carbonyl determination by a rhodamine B hydrazide-based fluorometric assay
A new fluorometric assay is presented for the ultrasensitive quantification of total protein carbonyls, and is based on their specific reaction with rhodamine B hydrazide (RBH), and the production of a protein carbonyl-RBH hydrazone the fluorescence of which (at ex/em 560/585 nm) is greatly enhanced by guanidine-HCl. Compared to the fluorescein-5-thiosemicarbazide (FTC)-based fluorometric assay, the RBH assay uses a 24-fold shorter reaction incubation time (1 h) and at least 1000-fold lower protein quantity (2.5 µg), and produces very reliable data that were verified by extensive standardization experiments. The protein carbonyl group detection sensitivity limit of the RBH assay, based on its standard curve, can be as low as 0.4 pmol, and even lower. Counting the very low protein limit of the RBH assay, its cumulative and functional sensitivity is 8500- and 800-fold higher than the corresponding ones for the FTC assay. Neither heme proteins hemoglobin and cytochrome c nor DNA interfere with the RBH assay. Keywords: Fluorometric method, Rhodamine B hydrazide, Protein carbonyls, Protein oxidation, Oxidative stress, DN