Απομόνωση, ταυτοποίηση και ποσοτικός προσδιορισμός της γ-ορυζανόλης και της πολικής γ-ορυζανόλης από παραπροϊόντα μύλευσης του ρυζιού (Oryza sativa L.)

Το πίτουρο είναι το σημαντικότερο υποπροϊόν της επεξεργασίας του ρυζιού από την εκχύλιση του οποίου προκύπτει το ρυζέλαιο (Rice Bran Oil - RBO). Το RBO είναι πλούσιο σε βιοδραστικές ενώσεις και ω-6 λιπαρά οξέα αλλά ξεχωρίζει από τα υπόλοιπα φυτικά έλαια χάρη στην υψηλά ποσοστά γ-ορυζανόλης, η οποία εμφανίζει πληθώρα φαρμακολογικών ιδιοτήτων. Αν και θεωρείται ως ένα από τα έλαια με τις περισσότερες ευεργετικές ιδιότητες στον κόσμο, δεν είναι ευρέως γνωστό. Η πολύπλοκη διαδικασία εξευγενισμού που το καθιστά ίσως πιο ακριβό σε σχέση με άλλα φυτικά έλαια μπορεί να αντισταθμιστεί από την σωστή εκμετάλλευση και την ανακύκλωση των υποπροϊόντων και των αποβλήτων που προκύπτουν από την επεξεργασία του ρυζιού με ευεργετικά οφέλη για το περιβάλλον και την υγεία. Από το 2009 και μετά παρατηρείται μία συνεχώς αυξανόμενη ζήτηση του RBO από το αγοραστικό κοινό κυρίως της Ασίας, γεγονός που καθιστά το RBO και τα υποπροϊόντα του ρυζιού, μία προσοδοφόρα επιχειρηματική ευκαιρία. Αυξημένο είναι και το ενδιαφέρον της επιστημονική κοινότητας παγκοσμίως για τις ευεργετικές για την υγεία ιδιότητες των συστατικών του. Στα πλαίσια αυτής της εργασίας αναπτύχθηκε μέθοδος ποσοτικοποίησης της γ-ορυζανόλης (γOR) και της πολικής γ-ορυζανόλης (PγOR) στα παραπροϊόντα μύλευσης του ρυζιού που θα επιτρέπει την επιλογή της πιο πλούσιας πρώτης ύλης για τη μετέπειτα απομόνωση των επιμέρους ενώσεων τους με τη χρήση διαφόρων χρωματογραφικών τεχνικών. Μελετήθηκαν συνολικά 12 δείγματα -δέκα δείγματα πίτουρου και δύο δείγματα φλοιού- τα οποία είναι υποπροϊόντα της επεξεργασίας του ρυζιού. Προήλθαν από την αποφλοίωση και τα διάφορα στάδια της μύλευσης του λευκού και κίτρινου (parboiled) ρυζιού της ποικιλίας Gladio και του λευκού ρυζιού της ποικιλίας Ronaldo. Από τα δείγματα παρασκευάστηκαν τα εκχυλίσματα ρυζελαίου και φλοιού, τα οποία αναλύθηκαν με την τεχνική HPLC. Με την ανάπτυξη κατάλληλης μεθόδου και την κατασκευή καμπύλης αναφοράς για την γOR και την PγOR πραγματοποιήθηκε ποσοτικός προσδιορισμός των ομάδων αυτών στο πίτουρο και στο φλοιό. Με βάση τα αποτελέσματα του ποσοτικού προσδιορισμού επιλέχθηκε το πιο πλούσιο δείγμα σε γOR & PγOR. Το δείγμα αυτό εκχυλίστηκε και με την ανάπτυξη κατάλληλης μεθόδου στην Χρωματογραφία Κατανομής με Φυγοκέντριση (CPC) η PγOR κλασματώθηκε και διαχωρίστηκε από τη γOR. Με την εφαρμογή επιπλέον χρωματογραφικών τεχνικών στα κλάσματα του CPC απομονώθηκαν μέσω semi prep-HPLC έξι ενώσεις της γOR και μέσω SFC-MS απομονώθηκαν έξι ενώσεις της 9 PγOR. Η ταυτοποίηση των απομονωμένων ενώσεων έγινε με εφαρμογή φασματοσκοπικών (1D & 2D NMR), φασματομετρικών (HRMS) μεθόδων και μελέτη των βιβλιογραφικών δεδομένων.The oil deriving from rice bran, namely rice bran oil (RBO), is one of the major by-product of the rice milling industry. RBO represents a rich source of ω-6 FFA and bioactive phytochemicals with pharmaceutical and cosmetic interest such as γ-oryzanol (γOR). γ-Oryzanol is of particular significance because it is abundant in RBO compared to other vegetable oils. Although RBO is considered to be one the healthiest oils in the world, it does not reach its full production potential. RBO is more expensive than other vegetable oils due to its complex refining process. However, the correct management of the wastes in the rice industry can reduce that cost. The exploitation and recycling of the main rice byproducts and residues is an economical opportunity that has benefits for the environment as well. Apart from the commercial part of the matter, the scientific community is interested more and more about the beneficial for the human health activities of RBO’s constituents, and especially γOR. The aim of the present study is, on the one hand, the determination and quantification of both γOR and PγOR components in rice bran and rice husk and on the other hand, the isolation and structural elucidation of their individual constituents. Initially, 12 different samples of rice bran and rice husk, of different varieties (Gladio and Ronaldo) obtained throughout the various steps of the milling process, with or without the parboiling technique (PB), were extracted independently twice via ultrasonic extraction using EtOAc. EtOAc was the optimum solvent for the extraction of both γOR and PγOR. The obtained RBO extracts yielded up to 25% (w/w). Additionally, a targeted HPLC-UV method was developed for the separation and quantification of γOR & PγOR in bran/husk (w/w). Taking into accounts the results of the quantification, Gladio parboiled 1st step bran (Gpb1) was chosen for the isolation of γOR’s & PγOR’s individual constituents, which is the second goal of the present study. The fractionation of PγOR and its separation from γOR was succeeded via CPC. The isolation of γOR’s & PγOR’s constituents demands the implementation of more than one chromatographic techniques. γOR’s individual constituents were isolated via semi prep-HPLC whereas PγOR’s individual constituents were isolated via prep- SFC-MS. Their structural elucidation was accomplished by combining LC-HRMSn and NMR (1D& 2D) data

Acid-fast bacteria as causative agents of skin and soft tissue infections: case presentations and literature review

Acid-fast bacteria can be implicated in skin and soft tissue infections. Diagnostic identification can be challenging or not feasible by routine laboratory techniques, especially if there is no access to the Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) technology. Here, we present two cases of skin and soft tissue infections caused by two different acid-fast bacteria, Nocardia brasiliensis and Mycobacterium marinum. They both grew on Löwenstein–Jensen medium, Sabouraud agar medium and blood agar medium. Both bacteria appeared acid-fast by Ziehl–Neelsen stain and Gram-positive by Gram stain. The identification was performed by MALDI-TOF MS and gene analysis. N. brasiliensis and nontuberculous mycobacterium M. marinum represent rare pathogens that cause severe skin and soft tissue infections. Failure to identify the causative agent and subsequent inappropriate or inadequate treatment may lead to severe complications or even disseminated disease, especially in immunocompromised individuals

Attitudes of Greek Health Care Professionals on Human Cloning

The aim of the study is to evaluate the attitudes and opinions of Greek health care professionals with regard to cloning. The sample included 303 individuals, medical and nursing personnel. An anonymous questionnaire was used and data analysis was performed using descriptive statistics, X2 (Chi Square) test and Mann-Whitney U test. More than 50% of the participants agree that cloning a) offends human dignity, b) devalues the role of the male in human reproduction and c) helps rescue endangered species. Eighty percent of the sample supports that cloning reduces the genetic diversity of humans and nature. Additionally, 71.2% of the sample stands against reproductive cloning, while 63.9% are in favor of therapeutic cloning. Independent variables that influence the attitudes towards cloning are: the importance of religion, the category of personnel (medical or nursing) and age. The majority of the participants do not consider reproductive cloning morally acceptable. Nevertheless, it is believed to help rescue endangered species. The participants consider therapeutic cloning important for the treatment of illnesses

Methods on LDL particle isolation, characterization, and component fractionation for the development of novel specific oxidized LDL status markers for atherosclerotic disease risk assessment

The present study uses simple, innovative methods to isolate, characterize and fractionate LDL in its main components for the study of specific oxidations on them that characterize oxidized low-density lipoprotein (oxLDL) status, as it causatively relates to atherosclerosis-associated cardiovascular disease (CVD) risk assessment. These methods are: (a) A simple, relatively time-short, low cost protocol for LDL isolation, to avoid shortcomings of the currently employed ultracentrifugation and affinity chromatography methodologies. (b) LDL purity verification by apoB100 SDS-PAGE analysis and by LDL particle size determination; the latter and its serum concentration are determined in the present study by a simple method more clinically feasible as marker of CVD risk assessment than nuclear magnetic resonance. (c) A protocol for LDL fractionation, for the first time, into its main protein/lipid components (apoB100, phospholipids, triglycerides, free cholesterol, and cholesteryl esters), as well as into LDL carotenoid/tocopherol content. (d) Protocols for the measurement, for the first time, of indicative specific LDL component oxidative modifications (cholesteryl ester-OOH, triglyceride-OOH, free cholesterol-OOH, phospholipid-OOH, apoB100-MDA, and apoB100-DiTyr) out of the many (known/unknown/under development) that collectively define oxLDL status, which contrasts with the current non-specific oxLDL status evaluation methods. The indicative oxLDL status markers, selected in the present study on the basis of expressing early oxidative stress-induced oxidative effects on LDL, are studied for the first time on patients with end stage kidney disease on maintenance hemodialysis, selected as an indicative model for atherosclerosis associated diseases. Isolating LDL and fractionating its protein and main lipid components, as well as its antioxidant arsenal comprised of carotenoids and tocopherols, paves the way for future studies to investigate all possible oxidative modifications responsible for turning LDL to oxLDL in association to their possible escaping from LDL’s internal antioxidant defense. This can lead to studies to identify those oxidative modifications of oxLDL (after their artificial generation on LDL), which are recognized by macrophages and convert them to foam cells, known to be responsible for the formation of atherosclerotic plaques that lead to the various CVDs

High Genetic Diversity among Community-Associated Staphylococcus aureus in Europe: Results from a Multicenter Study

Background: Several studies have addressed the epidemiology of community-associated Staphylococcus aureus (CA-SA) in Europe; nonetheless, a comprehensive perspective remains unclear. In this study, we aimed to describe the population structure of CA-SA and to shed light on the origin of methicillin-resistant S. aureus (MRSA) in this continent. Methods and Findings: A total of 568 colonization and infection isolates, comprising both MRSA and methicillin-susceptible S. aureus (MSSA), were recovered in 16 European countries, from community and community-onset infections. The genetic background of isolates was characterized by molecular typing techniques (spa typing, pulsed-field gel electrophoresis and multilocus sequence typing) and the presence of PVL and ACME was tested by PCR. MRSA were further characterized by SCCmec typing. We found that 59 % of all isolates were associated with community-associated clones. Most MRSA were related with USA300 (ST8-IVa and variants) (40%), followed by the European clone (ST80-IVc and derivatives) (28%) and the Taiwan clone (ST59-IVa and related clonal types) (15%). A total of 83 % of MRSA carried Panton-Valentine leukocidin (PVL) and 14 % carried the arginine catabolic mobile element (ACME). Surprisingly, we found a high genetic diversity among MRSA clonal types (ST-SCCmec), Simpson’s index of diversity = 0.852 (0.788–0.916). Specifically, about half of the isolates carried novel associations between genetic background and SCCmec. Analysis by BURP showed that some CA-MSSA and CA-MRS

Exploring causality in the association between circulating 25-hydroxyvitamin D and colorectal cancer risk:a large Mendelian randomisation study

Background: Whilst observational studies establish that lower plasma 25-hydroxyvitamin D (25-OHD) levels are associated with higher risk of colorectal cancer (CRC), establishing causality has proven challenging. Since vitamin D is modifiable, these observations have substantial clinical and public health implications. Indeed, many health agencies already recommend supplemental vitamin D. Here, we explore causality in a large Mendelian randomisation (MR) study using an improved genetic instrument for circulating 25-OHD. Methods: We developed a weighted genetic score for circulating 25-OHD using six genetic variants that we recently reported to be associated with circulating 25-OHD in a large genome-wide association study (GWAS) meta-analysis. Using this score as instrumental variable in MR analyses, we sought to determine whether circulating 25-OHD is causally linked with CRC risk We conducted MR analysis using individual-level data from 10,725 CRC cases and 30,794 controls (Scotland, UK Biobank and Croatia). We then applied estimates from meta-analysis of 11 GWAS of CRC risk (18,967 cases; 48,168 controls) in a summary statistics MR approach. Results: The new genetic score for 25-OHD was strongly associated with measured plasma 25-OHD levels in 2821 healthy Scottish controls (P = 1.47 x 10(-11)), improving upon previous genetic instruments (F-statistic 46.0 vs. 13.0). However, individual-level MR revealed no association between 25-OHD score and CRC risk (OR 1.03/unit log-transformed circulating 25-OHD, 95% CI 0.51-2.07, P= 0.93). Similarly, we found no evidence for a causal relationship between 25-OHD and CRC risk using summary statistics MR analysis (OR 0.91, 95% CI 0.69-1.19, P= 0.48). Conclusions: Despite the scale of this study and employing an improved score capturing more of the genetic contribution to circulating 25-OHD, we found no evidence for a causal relationship between circulating 25-OHD and CRC risk Although the magnitude of effect for vitamin D suggested by observational studies can confidently be excluded, smaller effects sizes and non-linear relationships remain plausible. Circulating vitamin D may be a CRC biomarker, but a causal effect on CRC risk remains unproven