80 research outputs found
Profiling of polar ionogenic metabolites in Polish wines by capillary electrophoresis-mass spectrometry
The composition of wine is determined by a complex interaction between environmental factors, genetic factors (i.e., grape varieties), and winemaking practices (including technology and storage). Metabolomics using NMR spectroscopy, GC-MS, and/or LC-MS has shown to be a useful approach for assessing the origin, authenticity, and quality of various wines. Nonetheless, the use of additional analytical techniques with complementary separation mechanisms may aid in the deeper understanding of wine's metabolic processes. In this study, we demonstrate that CE-MS is a very suitable approach for the efficient profiling of polar ionogenic metabolites in wines. Without using any sample preparation or derivatization, wine was analyzed using a 10-min CE-MS workflow with interday RSD values for 31 polar and charged metabolites below 3.8% and 23% for migration times and peak areas, respectively. The utility of this workflow for the global profiling of polar ionogenic metabolites in wine was evaluated by analyzing different cool-climate Polish wine samples.Analytical BioScience
Targeting Impaired Antimicrobial Immunity in the Brain for the Treatment of Alzheimer’s Disease
Alzheimer’s disease (AD) is the most common form of dementia and aging is the most common risk factor for developing the disease. The etiology of AD is not known but AD may be considered as a clinical syndrome with multiple causal pathways contributing to it. The amyloid cascade hypothesis, claiming that excess production or reduced clearance of amyloid-beta (Aβ) and its aggregation into amyloid plaques, was accepted for a long time as the main cause of AD. However, many studies showed that Aβ is a frequent consequence of many challenges/pathologic processes occurring in the brain for decades. A key factor, sustained by experimental data, is that low-grade infection leading to production and deposition of Aβ, which has antimicrobial activity, precedes the development of clinically apparent AD. This infection is chronic, low grade, largely clinically silent for decades because of a nearly efficient antimicrobial immune response in the brain. A chronic inflammatory state is induced that results in neurodegeneration. Interventions that appear to prevent, retard or mitigate the devel- opment of AD also appear to modify the disease. In this review, we conceptualize further that the changes in the brain antimicrobial immune response during aging and especially in AD sufferers serve as a foundation that could lead to improved treatment strategies for preventing or decreasing the progression of AD in a disease-modifying treatment
Structure and function of the Ts2631 endolysin of <i>Thermus scotoductus</i> phage vB_Tsc2631 with unique N-terminal extension used for peptidoglycan binding
Abstract To escape from hosts after completing their life cycle, bacteriophages often use endolysins, which degrade bacterial peptidoglycan. While mesophilic phages have been extensively studied, their thermophilic counterparts are not well characterized. Here, we present a detailed analysis of the structure and function of Ts2631 endolysin from thermophilic phage vB_Tsc2631, which is a zinc-dependent amidase. The active site of Ts2631 consists of His30, Tyr58, His131 and Cys139, which are involved in Zn2+ coordination and catalysis. We found that the active site residues are necessary for lysis yet not crucial for peptidoglycan binding. To elucidate residues involved in the enzyme interaction with peptidoglycan, we tested single-residue substitution variants and identified Tyr60 and Lys70 as essential residues. Moreover, substitution of Cys80, abrogating disulfide bridge formation, inactivates Ts2631, as do substitutions of His31, Thr32 and Asn85 residues. The endolysin contains a positively charged N-terminal extension of 20 residues that can protrude from the remainder of the enzyme and is crucial for peptidoglycan binding. We show that the deletion of 20 residues from the N-terminus abolished the bacteriolytic activity of the enzyme. Because Ts2631 exhibits intrinsic antibacterial activity and unusual thermal stability, it is perfectly suited as a scaffold for the development of antimicrobial agents
Синтез і цитотоксичність аміноетоксидифенілів
The implementation mechanism of the antiviral activity (AA) and interferon induction (IFI) by planar polycyclic compounds has not yet been determined. However, our hypothesis of the priority role of intercalation in double strand nucleic acids (NA) has gained strong arguments in its favour in our works and the works of foreign colleagues.On the other hand, the presence of AA and the ability to induce IFI in biphenyl derivatives that are incapable to intercalate in NA indicates the possibility of implementing alternative mechanisms. This determined our interest to the study of aminoethoxydiphenyls (AED), which synthesis and investigation of cytotoxicity become the subject of this article. 4,4’-Bis-(2-chloroethoxy)diphenyl was obtained by alkylation of dihydroxydiphenyl with dichloroethane in its mixture with aqueous sodium hydroxide (20%) in the presence of tetrabutylammonium chloride (TBAC). Series of AED were synthesized by substitution of chlorine by iodine in the mixture of xylene with the aqueous solution of sodium iodide in the presence of TBAC with subsequent amination with primary and secondary amines. The protonated molecular ions (MI) intensive peaks of the compounds synthesized are observed in the mass spectra with FAB ionization. The most common way of MI fragmentation is PhO-CH2-bond cleavage following the side aminoalkyl fragment detachment. Absorption bands typical for CH (arom.), CH (aliph.), COC bonds and NH protonated terminal amino groups are present in IR spectra. In the 1H-NMR spectra signals from aromatic and aliphatic protons present, multiplicity and integral intensity correspond to the attributed structures. Cytotoxicity of the compounds synthesized was tested using EPT cells in vitro. All AED tested appeared to be comparable to amixine and are in the range from low to moderate cytotoxicity.Механизм реализации противовирусной активности (ПА) и индукции индерферона (ИФН) планарными полициклическими соединениями до сих пор не установлен, хотя выдвинутая нами гипотеза о приоритетной роли интеркаляции в двухспиральные нуклеиновые кислоты (НК) получила весомые аргументы в свою пользу в наших работах и работах зарубежных коллег. С другой стороны, наличие ПА и способности индуцировать ИФН в производных дифенила, не способных к интеркаляции в НК, указывает на возможность реализации альтернативных механизмов. Это и определило наш интерес к развернутому исследованию аминоалкоксидифенила (ААД), началу которого – синтезу и исследованию цитотоксичности ААД и посвящена эта статья. Алкилированием дигидроксибифенила дихлорэтаном в смеси водного раствора гидроксида натрия (20%) с 1,2-дихлорэтаном в присутствии тетрабутиламмония хлорида (ТБАХ) получен 4,4’-бис-(2-хлороэтокси) бифенил. Замену хлора на йод проводили в смеси ксилола с водным раствором йодида натрия в присутствии ТБАЙ с последующим аминированием рядом первичных и вторичных аминов; синтезирован ряд АЭД. В масс-спектрах с ионизацией БУА синтезированных соединений имеются интенсивные пики протонированных молекулярных ионов (МИ), наиболее типичным путем фрагментации МИ является разрыв связи PhO-CH2 с отщеплением бокового аминоалкильного фрагмента. В ИК-спектрах наблюдаются полосы поглощения, характерные для связей CH (аром.), CH (алиф), COC и NH протонованных терминальных аминогрупп. В спектрах 1H-ЯМР имеются сигналы от ароматических и алифатических протонов, мультиплетность и интегральная интенсивность которых соответствуют приписываемым структурам. На клетках ПТП изучена цитотоксичность ряда 4,4’-бис-(2-аминоэтокси)дифенилов, значения сопоставимы с цитотоксичностью амиксина и находятся в диапазоне от низких до умеренных.Механізм реалізації противірусної активності (ПА) та індукції інтерферону (ІФН) планарними поліциклічними сполуками досі не встановлено, хоча висунута нами гіпотеза про пріоритетну роль інтеркаляції в двоспіральні нуклеїнові кислоти (НК) набула вагомих аргументів на свою користь в наших роботах та роботах іноземних колег. З іншого боку, наявність ПА та здатності індукувати ІФН у похідних дифенілу, не здатних до інтеркаляції у НК, вказує на можливість реалізації альтернативних механізмів. Це й спричинило наш інтерес до поглибленого дослідження аміноалкоксидифенілів (АЕД), початку якого – синтезу та дослідженню цитотоксичності АЕД і присвячена ця стаття. Алкілуванням дигідроксибіфенілу дихлороетаном у суміші водного розчину гідроксиду натрію (20%) з 1,2-дихлороетаном у присутності тетрабутиламонію хлориду (ТБАХ) отримано 4,4’-біс-(2-хлороетокси)біфеніл. Заміну хлору на йод проводили в суміші ксилолу з водним розчином йодиду натрію в присутності ТБАЙ з наступним амінуванням низкою первинних та вторинних амінів; синтезована низка АЕД. В мас-спектрах з іонізацією БПА синтезованих сполук наявні інтенсивні піки протонованих молекулярних іонів (МІ), найбільш типовим шляхом фрагментації МІ є розрив зв’язку PhO–CH2 з відщепленням бокового аміноалкільного фрагменту. В ІЧ-спектрах наявні смуги поглинання, характерні для зв’язків C-H (аром.), C-H (аліф), C-O-C та NH протонованих термінальних аміногруп. У спектрах 1H-ЯМР наявні сигнали від ароматичних та аліфатичних протонів, мультиплетність та інтегральна інтенсивність яких відповідає приписуваним структурам. На клітинах ПТП вивчена цитотоксичність низки 4,4’-біс-(2-аміноетокси)дифенілів, значення якої зіставні з токсичністю аміксину та знаходяться в діапазоні від низьких до помірних
Níveis iônicos e enzimáticos de cutias (Dasyprocta sp.) hígidas, criadas em cativeiro, influência do sexo e da idade
Multi-Center Fetal Brain Tissue Annotation (FeTA) Challenge 2022 Results
Segmentation is a critical step in analyzing the developing human fetal brain. There have been vast improvements in automatic segmentation methods in the past several years, and the Fetal Brain Tissue Annotation (FeTA) Challenge 2021 helped to establish an excellent standard of fetal brain segmentation. However, FeTA 2021 was a single center study, limiting real-world clinical applicability and acceptance. The multi-center FeTA Challenge 2022 focused on advancing the generalizability of fetal brain segmentation algorithms for magnetic resonance imaging (MRI). In FeTA 2022, the training dataset contained images and corresponding manually annotated multi-class labels from two imaging centers, and the testing data contained images from these two centers as well as two additional unseen centers. The multi-center data included different MR scanners, imaging parameters, and fetal brain super-resolution algorithms applied. 16 teams participated and 17 algorithms were evaluated. Here, the challenge results are presented, focusing on the generalizability of the submissions. Both in- and out-of-domain, the white matter and ventricles were segmented with the highest accuracy (Top Dice scores: 0.89, 0.87 respectively), while the most challenging structure remains the grey matter (Top Dice score: 0.75) due to anatomical complexity. The top 5 average Dices scores ranged from 0.81-0.82, the top 5 average 95th percentile Hausdorff distance values ranged from 2.3-2.5mm, and the top 5 volumetric similarity scores ranged from 0.90-0.92. The FeTA Challenge 2022 was able to successfully evaluate and advance generalizability of multi-class fetal brain tissue segmentation algorithms for MRI and it continues to benchmark new algorithms.10.13039/100014013-UK Research and Innovation (Grant Number: FLF (MR/T018119/1));
URPP Adaptive Brain Circuits in Development and Learning (AdaBD) Project;
10.13039/501100008494-Vontobel-Stiftung;
Anna M?ller Grocholski Foundation;
10.13039/100010269-Wellcome Trust (Grant Number: Sir Henry Wellcome Fellowship (201374/Z/16/Z and /);
10.13039/501100008464-EMDO Stiftung;
Prof. Dr Max Cloetta Foundation;
10.13039/501100001711-Schweizerischer Nationalfonds zur F?rderung der Wissenschaftlichen Forschung (Grant Number: SNSF 320030_184932, 205321?182602);
10.13039/501100000266-Engineering and Physical Sciences Research Council (Grant Number: EP/V034537/1);
10.13039/501100002428-Austrian Science Fund (Grant Number: FWF [P 35189-B], I 3925-B27);
10.13039/501100023312-Wellcome EPSRC Centre for Medical Engineering (Grant Number: WT203148/Z/16/Z);
10.13039/501100001821-Vienna Science and Technology Fund (Grant Number: WWTF [LS20-030]);
10.13039/501100006391-Centre d'Imagerie BioM?dicale;
10.13039/100000002-National Institutes of Health (Grant Number: Human Placenta Project?grant 1U01HD087202?01)
Measurement of distance, velocity and angle of arrival using FMCW-CW combined waveform
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