Έκφραση του γονιδίου DAZL σε τροφοβλαστικά κύτταρα μετά από CVS

Το γονίδιο DAZL αποτελεί δείκτη των γεννητικών κυττάρων και εκφράζεται σε εμβρυϊκά βλαστικά κύτταρα. Τα τελευταία χρόνια, η επιστημονική κοινότητα αναζητά τη σημασία της έκφρασής του σε διάφορους εμβρυϊκούς και εξωεμβρυϊκούς ιστούς. Σκοπός της παρούσας εργασίας ήταν η μελέτη της έκφρασης του γονιδίου DAZL και ειδικότερα η εύρεση έκφρασης ή όχι σε τροφοβλαστικά κύτταρα του πλακούντα. Τα κύτταρα αυτά ελήφθησαν με βιοψία χοριακών λαχνών, στα πλαίσια του προγεννητικού ελέγχου στο τέλος του 1ου τριμήνου της κύησης. Η έκφραση του γονιδίου DAZL στα τροφοβλαστικά κύτταρα μελετήθηκε με την τεχνική Real – Time PCR και διαπιστώθηκε ελάχιστη θετική έκφραση, διαφορετική του μηδενός, η οποία δε μπορεί να θεωρηθεί αμελητέα. Η σύγκριση με τα αποτελέσματα άλλων αντίστοιχων μελετών έδειξε συμφωνία των αποτελεσμάτων. Συνεπώς, η εύρεση έκφρασης του γονιδίου DAZL στα τροφοβλαστικά κύτταρα φαίνεται να σχετίζεται με τη δυνητική ικανότητα διαφοροποίησης των κυττάρων αυτών σε γεννητικά κύτταρα κάτω από τις κατάλληλες συνθήκες, ανοίγωντας έτσι νέα μονοπάτια στους τομείς της έρευνας και της αναγεννητικής ιατρικής.The DAZL gene is a germ cell marker and it is expressed in embryonic stem cells. In recent years, the scientific community is looking for the importance of its expression in various embryonic and extra-embryonic tissues. The purpose of this study was to search the expression of DAZL gene and, in particular, the finding of gene expression or not in trophoblastic cells of the placenta. These cells were obtained by chorionic villus sampling (CVS), in the context of prenatal diagnostic testing at the end of the first trimester of pregnancy. The DAZL gene expression in trophoblastic cells was measured with the Real - Time PCR technique and demonstrated minimal gene expression, different from zero, which cannot be considered negligible. The comparison with other relevant studies revealed agreement of the results. Therefore, the finding of DAZL gene expression in trophoblastic cells seems to be related to the potential capacity of these cells to differentiate into germ cells under appropriate conditions, opening new paths in the fields of research and regenerative medicine

Μελέτη Μεντελιανής Τυχαιοποίησης για τη συσχέτιση διατροφικών χαρακτηριστικών με τον καρκίνο παχέος εντέρου

Εισαγωγή: Ο καρκίνος του παχέος εντέρου είναι ο τρίτος πιο διαδεδομένος καρκίνος παγκοσμίως απαριθμώντας πάνω από 1.2 εκατομμύρια νέες περιπτώσεις και 600.000 θανάτους ανά έτος. Ορισμένα χαρακτηριστικά σχετιζόμενα με τη διατροφή είναι γνωστοί παράγοντες κινδύνου για τον καρκίνο του παχέος εντέρου ενώ για την πλειοψηφία των διατροφικών παραγόντων, οι ενδείξεις ήταν είτε ασαφείς είτε περιορισμένες. Τα περισσότερα στοιχεία σχετικά με τη διατροφή και τον κίνδυνο ανάπτυξης καρκίνου προκύπτουν από μελέτες παρατήρησης. Σκοπός της παρούσας μελέτης είναι να ξεπεραστούν οι περιορισμοί αυτών των μελετών με τη χρήση της μεθόδου της Μενδελιανής τυχαιοποίησης. Εκτιμήθηκαν συσχετίσεις μεταξύ των γενετικά καθορισμένων προσλήψεων διατροφικών παραγόντων και του κινδύνου ανάπτυξης καρκίνου του παχέος εντέρου. Διεξήχθησαν αναλύσεις για τους ακόλουθους διατροφικούς παράγοντες: δημητριακά, φρέσκα φρούτα, επεξεργασμένο κρέας, πουλερικά, λιπαρά ψάρια, μη λιπαρά ψάρια, τυρί, τσάι και πράσινο τσάι. Μέθοδος: Πραγματοποιήθηκε μελέτη Μενδελιανής τυχαιοποίησης δύο δειγμάτων με τη χρήση περιληπτικών δεδομένων. Τα δεδομένα για τη σχέση των SNPs με τον καρκίνο του παχέος εντέρου αντλήθηκαν από 58,221 ασθενείς και 67,694 μάρτυρες από τη GECCO. Οι διατροφικοί παράγοντες επιλέχθηκαν από το World Cancer Research Fund (WCRF) Continuous Update Project (CUP) και τα περιληπτικά δεδομένα για τη σχέση τους με τα SNPs προήλθαν από GWAS της UK Biobank. Εφαρμόστηκε η μέθοδος Inverse Variance Weighted (IVW) για την εκτίμηση της αιτιακής σχέσης και πραγματοποιήθηκαν αναλύσεις ευαισθησίας (simple median, weighted median, MR-Egger, weighted mode, MR-PRESSO) για τον έλεγχο των παραδοχών της Μενδελιανής τυχαιοποίησης. Επιπρόσθετα, διεξήχθησαν αναλύσεις ανά υπότυπο του καρκίνου του παχέος εντέρου (κόλον, δεξί κόλον, αριστερό κόλον και ορθό). Αποτελέσματα: Η γενετικά καθορισμένη κατανάλωση λιπαρών ψαριών συσχετίστηκε με 27% χαμηλότερο κίνδυνο ανάπτυξης καρκίνου του παχέος εντέρου (Odds Ratio [OR]=0.73, 95% Διάστημα Εμπιστοσύνης [ΔΕ]=(0.58-0.92)), 30% χαμηλότερο κίνδυνο ανάπτυξης καρκίνου του κόλου (OR=0.70, 95% ΔΕ=(0.54-0.91)) και 37% χαμηλότερο κίνδυνο ανάπτυξης καρκίνου του αριστερού κόλου (OR=0.63, 95% ΔΕ=(0.46-0.85)). Επίσης, παρατηρήθηκε προστατευτική επίδραση της γενετικά καθορισμένης κατανάλωσης δημητριακών στον καρκίνου του ορθού (OR=0.59, 95% ΔΕ=(0.38-0.89)), ενώ οριακής στατιστικής σημαντικότητας προστατευτική συσχέτιση παρατηρήθηκε για τον ολικό καρκίνο παχέος εντέρου (OR=0.75, 95% ΔΕ=(0.55-1.01)). Προστατευτική επίδραση παρατηρήθηκε και για τη γενετικά καθορισμένη κατανάλωση φρέσκων φρούτων με τον καρκίνο του αριστερού κόλου (OR=0.58, 95% ΔΕ=(0.37-0.89)) χωρίς όμως να ενισχύεται από τις εκτιμήσεις των αναλύσεων ευαισθησίας. Δεν παρατηρήθηκε συσχέτιση των υπόλοιπων διατροφικών παραγόντων με τον καρκίνο του παχέος εντέρου. Συμπεράσματα: Τα ευρήματα έδειξαν πιθανή προστατευτική επίδραση των λιπαρών ψαριών στον ολικό καρκίνο του παχέος εντέρου, το ολικό κόλον και το αριστερό κόλον και ήπια προστατευτική των δημητριακών με τον ολικό καρκίνο του παχέος εντέρου και τον καρκίνο του ορθού. Παρόλα αυτά, δεν μπορούμε να αποφανθούμε με σιγουριά αιτιότητα λόγω πιθανής ύπαρξης πλειοτροπίας. Περαιτέρω μελέτες πρέπει να πραγματοποιηθούν στο μέλλον ώστε να επιβεβαιωθούν αυτά τα ευρήματα και να καταλήξουν σε στιβαρά αποτελέσματα.Background: Colorectal cancer is the third most common type of cancer worldwide with over one million new cases and 600,000 deaths each year. Several nutrition-related characteristics are well-established risk factors of colorectal cancer but for the vast majority of dietary factors the evidence was either inconclusive or limited. Most of the evidence regarding diet and risk of cancer occurrence emerges from observational studies. The aim of this study is to overcome their inherent limitations using the Mendelian randomization (MR) approach. Associations were estimated between genetically determined intakes of dietary factors and risk of colorectal cancer. We run analyses for the following dietary factors: cereals, fresh fruits, processed meat, poultry, oily fish, non-oily fish, cheese, tea and green tea. Methods: A two-sample MR study was conducted using summary data. Data for the association between the selected SNPs and risk of colorectal cancer were retrieved from 58,221 cases and 67,694 controls from GECCO. Diet factors were selected from World Cancer Research Fund (WCRF) Continuous Update Project (CUP) and summary data of their association with the SNPs stemmed from GWAS from the UK Biobank. Inverse Variance Weighted (IVW) method was implemented for the assessment of potential causality and sensitivity analyses (simple median, weighted median, MR-Egger weighted mode, MR-PRESSO) were performed to secure the non-violation of the MR assumptions. Subgroup analyses were conducted according to cancer anatomical distribution (colon, distal colon, proximal colon and rectal cancer). Results: One standard deviation (SD: highest vs lowest consumption) higher genetically determined consumption of oily fish was associated with a 27% (Odds Ratio [OR]= 0.73, 95% Confidence Interval [CI]=(0.58 -0.92), 30% (OR=0.70, 95% CI=0.54 -0.91)) and 37% (OR= 0.63, 95% CI=(0.46 -0.85)) lower risk of colorectal, colon and distal colon cancer, respectively. An inverse association was observed for a SD higher genetically determined consumption of cereals and rectal cancer (OR=0.59, 95% CI=(0.38-0.89)). A suggestive inverse association was observed for a SD higher genetically determined consumption of cereals with overall colorectal cancer (OR= 0.75, 95% CI=(0.55-1.01)). A suggestive inverse association was observed for a SD higher genetically determined consumption of fresh fruits with distal cancer (OR= 0.58, 95% CI=(0.37-0.89)) but was not robust to sensitivity analyses. There was no evidence that any of the other dietary factors were associated with colorectal cancer. Conclusions: There was an inverse association between oily fish and colorectal cancer, colon cancer and distal colon cancer. A suggestive inverse association was observed between cereals and both colorectal and rectal cancer. However, strong evidence cannot be proven due to potential pleiotropy. Further work is required to replicate and strengthen these findings

Appraising the causal role of risk factors in coronary artery disease and stroke:A systematic review of Mendelian Randomization studies

BACKGROUND Mendelian randomization (MR) offers a powerful approach to study potential causal associations between exposures and health outcomes by using genetic variants associated with an exposure as instrumental variables. In this systematic review, we aimed to summarize previous MR studies and to evaluate the evidence for causality for a broad range of exposures in relation to coronary artery disease and stroke. METHODS AND RESULTS MR studies investigating the association of any genetically predicted exposure with coronary artery disease or stroke were identified. Studies were classified into 4 categories built on the significance of the main MR analysis results and its concordance with sensitivity analyses, namely, robust, probable, suggestive, and insufficient. Studies reporting associations that did not perform any sensitivity analysis were classified as nonevaluable. We identified 2725 associations eligible for evaluation, examining 535 distinct exposures. Of them, 141 were classified as robust, 353 as probable, 110 as suggestive, and 926 had insufficient evidence. The most robust associations were observed for anthropometric traits, lipids, and lipoproteins and type 2 diabetes with coronary artery; disease and clinical measurements with coronary artery disease and stroke; and thrombotic factors with stroke. CONCLUSIONS Despite the large number of studies that have been conducted, only a limited number of associations were supported by robust evidence. Approximately half of the studies reporting associations presented an MR sensitivity analysis along with the main analysis that further supported the causality of associations. Future research should focus on more thorough assessments of sensitivity MR analyses and further assessments of mediation effects or nonlinearity of associations

Microwave synthesis, characterization and perspectives of wood pencil-derived carbon

More than 14 billion pencils are manufactured and used globally every year. On average, a pencil is discarded after 60% of its original length has been depleted. In the present work we propose a simple and affordable way of converting this non-neglectable amount of waste into added value carbon product. In particular, we demonstrate the microwave synthesis of carbon from the wood pencil with and without chemical activation. This could be a process stage before the final recycling of the expensive graphite core. In the latter case, irradiation of the wood pencil in a domestic microwave oven heats up the pencil's graphite core, thus inducing carbonization of its wood casing. The carbonized product consists of amorphous carbon nanosheets having relatively low surface area. However, if the wood pencil is soaked in 50% KOH aqueous solution prior to microwave irradiation, a significantly higher surface area of carbon is obtained, consisting of irregular-shaped porous particles. Consequently, the obtained carbon can easily decolorize a methylene blue aqueous solution, can be used to make pocket warmers or gunpowder, and lastly, serves as an excellent adsorbent towards Cr(VI) removal from water, showing a maximum adsorption capacity of 70-75 mg/g within 24 h at 23 degrees C, pH = 3.Web of Science121art. no. 41

Nanoporous Activated Carbon Derived via Pyrolysis Process of Spent Coffee: Structural Characterization. Investigation of Its Use for Hexavalent Chromium Removal

Hexavalent chromium (Cr(VI)) is a heavy metal that is highly soluble and exhibits toxic effects on biological systems. Nevertheless, it is used in many industrial applications. The adsorption process of Cr(VI), using activated carbon (AC), is under investigation globally. On the other hand, around six million tons of spent coffee is sent to landfill annually. In the spirit of cyclic economy, this research investigated the production of AC from spent coffee for the removal of Cr(VI) from wastewater. The AC was produced via pyrolysis process under a nitrogen atmosphere. Chemical activation using potassium hydroxide (KOH) occurred simultaneously with the pyrolysis process. The produced AC was tested as an absorber of Cr(VI). The best fitted kinetic model was the diffusion–chemisorption model. A 24-h adsorption experiment was carried out using a solution with a pH of 3 and an initial Cr(VI) concentration of 54.14 ppm. This resulted in an experimental maximum capacity of 109 mg/g, while the theoretical prediction was 137 mg/g. It also resulted in an initial adsorption rate (ri) of 110 (mg/(g h)). The Brunauer–Emmett–Teller surface area (SgBET) was 1372 m2/g, the Langmuir surface area (SgLang.) was 1875 m2/g, and the corrugated pore structure model surface area (SgCPSM) was 1869 m2/g. The micropore volume was 84.6%, exhibiting micropores at Dmicro1 = 1.28 and Dmicro2 = 1.6 nm. The tortuosity factor (τ) was 4.65

Nanocomposites of Barium Titanate Nanoparticles Embedded in Thermosetting Polymer Matrices (Novolac Resin/Unsaturated Polyesters/Epoxy Resin): A Comparative Study

Polymer matrix nanocomposites with embedded ferroelectric barium titanate particles were developed and characterized. The utility of such nanocomposites is the energy storage capability that they exhibit, besides their low weight and cost, in comparison to materials that are customarily used for this purpose. The polymers that have been used as matrices in the composites belong to the three most usable thermosetting polymer resins (novolacs, unsaturated polyesters, and epoxy resins), were either laboratory synthesized or commercially supplied. Structure and morphology of the produced composite specimens were studied via Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), and Fourier Transformation Infrared Spectroscopy (FTIR). Thermal, mechanical and electrical performance was examined via Differential Scanning Calorimetry (DSC), bending and shear strength tests (three-point method), and Broadband Dielectric Spectroscopy (BDS), respectively. Mechanical shear and bending strength values were determined, as well as mechanical failure mode (brittle or elastomer) were estimated. Dielectric measurements disclosed the presence of four relaxation processes (α-mode, β-mode, and γ-mode) and Interfacial Polarization between the system’s constituents. The comparative study ended with the calculation of energy density, so that the energy storing capability could be estimated

Links between the genetic determinants of morning plasma cortisol and body shape: a two-sample Mendelian randomisation study

Abstract High cortisol production in Cushing’s syndrome leads to fat centralisation. The influence of modest cortisol variations on body shape, however, is less clear. We examined potentially causal associations between morning plasma cortisol and body shape and obesity with inverse-variance weighted random-effects models in a two-sample Mendelian randomisation analysis. We used publicly available summary statistics from the CORtisol NETwork (CORNET) consortium, UK Biobank, and the Genetic Investigation of Anthropometric Traits (GIANT) consortium. Only in women, morning plasma cortisol (proxied by ten genetic polymorphisms) was associated positively with waist size reflected in waist-to-hip index (WHI, 0.035 standard deviation (SD) units change per one SD cortisol increase; 95% confidence interval (0.002–0.067); p = 0.036) and “a body shape index” (ABSI; 0.039 (0.006–0.071); p = 0.021). There was no evidence for associations with hip index (HI) or body mass index (BMI). Among individual polymorphisms, rs7450600 stood out (chromosome 6; Long Intergenic Non-Protein-Coding RNA 473 gene, LINC00473). Morning plasma cortisol proxied by rs7450600 was associated positively with WHI and inversely with HI and BMI in women and men. Our findings support a causal association of higher morning plasma cortisol with larger waist size in women and highlight LINC00473 as a genetic link between morning plasma cortisol and body shape

Individualized Approach in the Surgical Management of Hepatocellular Carcinoma: Results from a Greek Multicentre Study

Background: Hepatocellular carcinoma (HCC) is the most common primary liver cancer and the third leading cause of death worldwide. The management of HCC is complex, with surgical treatment providing long-term survival in eligible patients. This study aims to present the experience of aggressive surgical management of HCC in Greece. Methods: This is a retrospective multicentre clinical study with 242 patients. Results: Most patients were male (79%) and had a median age of 71 yrs. According to the most recent BCLC criteria, 172 patients (71.1%) were classified as BCLC 0-A stage, 33 patients (13.6%) were classified as BCLC B, and 37 (15.3%) were classified as BCLC C. A total of 54% of the patients underwent major hepatectomy. Major postoperative morbidity was 15.6%, and the 90-day postoperative mortality rate was 4.5%. The median follow-up was 33.5 months. Three- and five-year overall survival was 65% and 48%, respectively. The median overall survival was 55 months. Significantly, five-year survival was 55% for BCLC A, and 34% and 21% for BCLC B and C, respectively. In univariate analysis, cirrhosis, type of resection (R status), and BCLC stage were associated with overall survival. Multivariate analysis indicated that R1 and R2 resections compared to R0, and BCLC C compared to BCLC 0-A, were independently associated with increased mortality. Conclusions: Aggressive surgical treatment of HCC offers satisfactory long-term survival prospects. A significant percentage (29%) of HCCs that underwent liver resection were of the intermediate and advanced BCLC stage. The management of patients with HCC should be discussed in multidisciplinary tumour board meetings on a case-by-case basis to be more effective

Hypergolic Synthesis of Inorganic Materials by the Reaction of Metallocene Dichlorides with Fuming Nitric Acid at Ambient Conditions: The Case of Photocatalytic Titania

Hypergolic materials synthesis is a new preparative technique in materials science that allows a wide range of carbon or inorganic solids with useful properties to be obtained. Previously we have demonstrated that metallocenes are versatile reagents in the hypergolic synthesis of inorganic materials, such as γ-Fe2O3, Cr2O3, Co, Ni and alloy CoNi. Here, we go one step further by using metallocene dichlorides as precursors for the hypergolic synthesis of additional inorganic phases, such as photocatalytic titania. Metallocene dichlorides are closely related to metallocenes, thus expanding the arsenal of organometallic compounds that can be used in hypergolic materials synthesis. In the present case, we show that hypergolic ignition of the titanocene dichloride–fuming nitric acid pair results in the fast and spontaneous formation of titania nanoparticles at ambient conditions in the form of anatase–rutile mixed phases. The obtained titania shows good photocatalytic activity towards Cr(VI) removal (100% within 9 h), with the latter being dramatically enhanced after calcination of the powder at 500 °C (100% within 3 h). Notably, this performance was found to be comparable to that of commercially available P25 TiO2 under identical conditions. The cases of zirconocene, hafnocene and molybdocene dichlorides are discussed in this work, which aims to show the wider applicability of metallocene dichlorides in the hypergolic synthesis of inorganic materials (ZrO2, HfO2, MoO2)