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Advanced approaches to produce polyhydroxyalkanoate (PHA) biopolyesters in a sustainable and economic fashion

: degree of polymerization; *: chiral carbon atom in most PHA building blocks. The improvement of large-scale productivity, cost efficiency, and strain performance demands optimization procedures of different process steps. This includes the quest for new wild type and genetically modified microbes, development of a process design adapted to the kinetic characteristics PHA production, and ecologically benign and efficient techniques for separation of PHA and residual non-PHA biomass. Only the synopsis of these steps allows ecologically feasible and sustainable

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3D polyelectrolyte scaffolds to mimic exocrine glands: a step towards a prostate-on-chip platform

to custom-made magnetic reversed-phase particles, the substances were eluted and separated by capillary high-performance liquid chromatography. Fractions were spotted directly on a MALDI target, and MALDI-TOF mass spectrometric data acquisition was performed in automatic mode. This technology was used to detect substances secreted by two mammary carcinoma cell lines differing in their malignancy (MCF-7, MDA-MB231). Unequivocal differences in the peptide secretion patterns were observed. In conclusion, this system allows the sensitive investigation of peptides

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Bio-economy in Greece: Current trends and the road ahead

fostered ( 20 ); (b) the National renewable energy action plan (2010) – in accordance with the EU’s 20% renewable energy target by 2020 ( 16 ) and (c) Law 4414/2016 that drafts the national strategy for protection against the effects of climate change and provides a new Support Scheme for power plants from renewable energy sources and cogeneration of high performance electricity and heat ( 21 ). Table 1 A compilation of currently active institutions in Bio-economy and Bio-economy related issues 1. The Rural Development Programme (2014-2020) Relevant 2

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Classification of coronary artery disease data sets by using a deep neural network

Abstract

In this study, a deep neural network classifier is proposed for the classification of coronary artery disease medical data sets. The proposed classifier is tested on reference CAD data sets from the literature and also compared with popular representative classification methods regarding its classification performance. Experimental results show that the deep neural network classifier offers much better accuracy, sensitivity and specificity rates when compared with other methods. The proposed method presents itself as an easily accessible and cost-effective alternative to currently existing methods used for the diagnosis of CAD and it can be applied for easily checking whether a given subject under examination has at least one occluded coronary artery or not.

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Formal- and high-structured kinetic process modelling and footprint area analysis of binary imaged cells: Tools to understand and optimize multistage-continuous PHA biosynthesis

Abstract

Competitive polyhydroxyalkanoate (PHAs) production requires progress in microbial strain performance, feedstock selection, downstream processing, and more importantly according to the process design with process kinetics of the microbial growth phase and the phase of product formation. The multistage continuous production in a bioreactor cascade was described for the first time in a continuously operated, flexible five-stage bioreactor cascade that mimics the characteristics involved in the engineering process of tubular plug flow reactors. This process was developed and used for Cupriavidus necator-mediated PHA production at high volumetric and specific PHA productivity (up to 2.31 g/(Lh) and 0.105 g/(gh), respectively). Based on the experimental data, formal kinetic and high structured kinetic models were established, accompanied by footprint area analysis of binary imaged cells. As a result of the study, there has been an enhanced understanding of the long-term continuous PHA production under balanced, transient, and nutrient-deficient conditions that was achieved on both the micro and the macro kinetic level. It can also be concluded that there were novel insights into the complex metabolic occurrences that developed during the multistage- continuous production of PHA as a secondary metabolite. This development was essential in paving the way for further process improvement. At the same time, a new method of specific growth rate and specific production rate based on footprint area analysis was established by using the electron microscope.

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Lower limb phantom design and production for blood flow and pressure tests

Abstract

Phantoms are specifically designed objects that are utilized or imaged to evaluate, analyze and tune the performance of experimental devices. In this project, it is aimed to design a phantom that responds in a similar manner with how human blood circulation would act in specific flow and pressure tests such as pulse measurement. Ballistic gelatin is a member of hydrogel family with 250 Bloom value which resembles human muscle tissue in terms of mechanical features. That’s why we carried out a uniaxial compression test on our gelatin sample to analyze its similarity of human muscle tissue in terms of elastic modulus, stiffness and rupture strength. Test results indicated that our gelatin sample has approximate values with organic human muscle tissue. Designed model was X-rayed and the similarities of the model to human texture were compared. After producing of lower limb phantoms, we carried out a circulation test through them by the aid of a peristaltic pump to simulate the actual blood circulation of human body limbs. This designed phantom is made ready for available flow and pressure tests.

Open access
Electrochemical impedimetric detection of stroke biomarker NT-proBNP using disposable screen-printed gold electrodes

Abstract

Stroke is the second top leading cause of death globally. It is caused by an abrupt interruption of blood flow to the brain. In that course, brain natriuretic peptide (BNP) and its derivative N-terminal pro b-type natriuretic peptide (NT-proBNP), neurohormones produced mainly by the heart ventricles in response to excessive stretching of cardiomyocytes (heart muscle cells), are proven to be good biomarkers for heart failure diagnosis. Moreover, there is growing clinical interest of the use of NT-proBNP for stroke diagnosis and prognosis because it is significantly associated with cardioembolic stroke and secondary stroke reoccurrence, with sensitivity >90% and specificity >80%. However, in diagnostic settings, there is still a need to address the encountered analytical problems, particularly assay specificity and set up. In this study, a novel approach for NT-proBNP detection is demonstrated using an electrochemical immunoassay method. A label-free impedimetry immunosensor for stroke biomarker was developed using modified disposable screen-printed gold electrodes (SPGE) hosting specific anti-NT-proBNP capture antibody. The performance of our immunosensor was studied in the presence of NT-proBNP in both buffered and mock (porcine) plasma samples. A linear relation between the relative total resistance (ΔRtot) responses and the NT-proBNP concentrations in buffer was observed in a range from 0.1 to 5 ng mL-1 with a correlation coefficient (R2) of 0.94656. Overall, the biosensor has demonstrated the capability to quantitate NT-proBNP and differentiate such concentrations in a low concentration range, especially among 0, 0.1, 0.5, 1, and 3 ng mL-1 in plasma samples within 25 min. This range is valuable not only for classifying cardioembolic stroke (higher or equal to 0.5 ng mL-1), but also predicting the risk of secondary stroke reoccurrence (higher than 0.255 ng mL-1). Our biosensor has the potential to be used as an easy-to-use point-of-care test that is both accurate and affordable.

Open access
Applying gas chromatography to monitor extracellular free amino acids content in cultivation medium during lactic acid fermentation

-74. 11. Le Boucher J, Charret C, Coudray-Lucas C, Giboudeau J, Cynober L. Amino acid determination in biological fluids by automated ion-exchange chromatography: performance of Hitachi L-8500A. Clinical Chem 1997; 43: 1421-28. 12. Salazar C, Armenta JM, Cortes DF, Shulaev V. Combination of an AccQ・Tag-Ultra Performance Liquid Chromatographic Method with Tandem Mass Spectrometry for the Analysis of Amino Acids, in Alterman, MA, Hunziker P. (Ed), Amino Acid Analysis: Methods and Protocols, Methods in Molecular Biology, vol. 828, Springer, 2012, pp. 13

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Organic selenium effect on body temperature and body weight in broilers

References 1. Niu ZY, Liu FZ, Yan QL and Li WC. Effects of different levels of vitamin E on growth performance and immune responses of broilers under heat stress. Poult Sci. 2009 Oct; 88(10):2101. 2. Sahin N, Sahin K, Oderci M. Vitamin E and selenium supplementation to alleviate cold stress associated deterioration in egg quality and egg yolk mineral., Biol Trace Elem. Res. Winter 2003; 96(1-3):179-89 3. Panda AK, Ramarao SV, Raju MV, Chatterjee RN, Effect of dietary supplementation with vitamins E and C on

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Synthesis of disulphide-Schiff base derivatives and investigations of in vitro antimicrobial activities against some human pathogens

extended synthesis of bioactive dithiobis( phenylene) bis(benzylideneimine) via sequential oxidative coupling-condensation reactions in one pot from aminothiophenol and benzaldehyde.J Mol Catal B-Enzym 2015; 116: 113-123. 13. Clinical and Laboratory Standards Institute. Performance Standards for Antimicrobial Susceptibility Testing: 25th Informational Supplement. CLSI Document M100-S25. Wayne, Pennsylvania: Clinical and Laboratory Standards Institute; 2015. 14. Tomma JH, Rouil I, and Al-Dujaili AH. Synthesis and mesomorphic behaviour of

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