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Candidate reference measurement procedure based on HPAEC-PAD for the development of certified reference materials for monosaccharides in serum.

Anal Bioanal Chem 2021 Jul 20. Epub 2021 Jul 20.

Biometrology Group, Division of Chemical and Biological Metrology, Korea Research Institute of Standards and Science, 267 Gajeong-ro, Yuseong-Gu, Daejeon, 34113, Republic of Korea.

To achieve the measurement reliability of monosaccharides used as diagnostic markers in clinical fields, it is essential to establish certified reference materials (CRMs). The purpose of this study is to develop a serum CRM by adopting high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) as a new candidate reference measurement procedure for the measurement of glucose and galactose, common diagnostic markers of diabetes and galactosemia, respectively. Using various monosaccharides as internal standards, the accuracy of the HPAEC-PAD method was tested by measuring glucose CRM following treatment with three different deproteinization methods: ultrafiltration, protein precipitation by trichloroacetic acid (TCA), and protein precipitation by acetonitrile. Read More

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Multi-Omics Analysis Reveals Disturbance of Nanosecond Pulsed Electric Field in the Serum Metabolic Spectrum and Gut Microbiota.

Front Microbiol 2021 2;12:649091. Epub 2021 Jul 2.

Shulan (Hangzhou) Hospital Affiliated to Zhejiang Shuren University, Shulan International Medical College, Hangzhou, China.

Nanosecond pulsed electric field (nsPEF) is a novel ablation technique that is based on high-intensity electric voltage to achieve tumour-killing effect in the target region, and increasingly considered for treating tumours of the liver, kidneys and other organs with rich blood supply. This study aims to observe effect of nsPFE treatment on serum metabolites and gut microbiota. The serum and faecal specimens of the pigs were collected pre- and post-treatment. Read More

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The Determination of Carbohydrates by High-Performance Anion-Exchange Chromatography Coupled with Pulsed Amperometric Detection (HPAEC-PAD).

Methods Mol Biol 2021 ;2356:57-68

Johannes Gutenberg University Mainz, Microbiology and Wine Research at the Institute for Molecular Physiology, Mainz, Germany.

Chromatography techniques are widely used to separate, identify, and quantify molecules depending on their physicochemical properties. Standard methods range from simple size exclusion to separation based on affinity or ion exchange. Here, we present a method for the direct analysis of carbohydrates in Magnaporthe oryzae using high-performance anion-exchange chromatography (HPAEC) coupled with pulsed amperometric detection (PAD). Read More

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January 2021

Strains Isolated From Danish Cheese Brines Act as Biocontrol Agents to Inhibit Germination and Growth of Contaminating Molds.

Front Microbiol 2021 15;12:662785. Epub 2021 Jun 15.

Department of Food Science, Faculty of Science, University of Copenhagen, Copenhagen, Denmark.

The antagonistic activities of native strains isolated from Danish cheese brines were evaluated against contaminating molds in the dairy industry. Determination of chromosome polymorphism by use of pulsed-field gel electrophoresis (PFGE) revealed a huge genetic heterogeneity among the strains, which was reflected in intra-species variation at the phenotypic level. 11 strains were tested for their ability to inhibit germination and growth of contaminating molds, frequently occurring at Danish dairies, i. Read More

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Improvement of Must Fermentation from Late Harvest cv. Tempranillo Grapes Treated with Pulsed Light.

Foods 2021 Jun 18;10(6). Epub 2021 Jun 18.

enotecUPM, Chemistry and Food Technology Department, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Avenida Puerta de Hierro 2, 28040 Madrid, Spain.

Pulsed light irradiation is a nonthermal technology currently used for the elimination of pathogens from a diverse range of food products. In the last two decades, the results obtained using PL at laboratory scale are encouraging wine experts to use it in the winemaking industry. PL can reduce native yeast counts significantly, which facilitates the use of starter cultures, reducing SO requirements at the same time. Read More

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Extraction and Characterization of Hemicelluloses from a Softwood Acid Sulfite Pulp.

Polymers (Basel) 2021 Jun 22;13(13). Epub 2021 Jun 22.

CNRS, University Bordeaux, Bordeaux INP, LCPO, UMR 5629, 33600 Pessac, France.

Hemicelluloses were extracted from a softwood acid sulfite pulp in a three-step procedure. Further delignification step resulted in a holocellulose pulp containing only 1.7 wt. Read More

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Crystal structure of a homotrimeric verrucomicrobial --1,4-mannosidase active in the hindgut of the wood-feeding termite .

J Struct Biol X 2021 24;5:100048. Epub 2021 May 24.

School of Engineering Sciences in Chemistry, Biotechnology, and Health (CBH), KTH Royal Institute of Technology, Roslagstullsbacken 21, SE-11421 Stockholm, Sweden.

The termite causes extensive damage due to the high efficiency and broad specificity of the ligno- and hemicellulolytic enzyme systems produced by its symbionts. Thus, the gut microbiome is expected to constitute an excellent source of enzymes that can be used for the degradation and valorization of plant biomass. The symbiont bacterium strain TAV5 belongs to the phylum Verrucomicrobia and thrives in the hindgut of . Read More

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Acoustic Mist Ionization Mass Spectrometry for Ultrahigh-Throughput Metabolomics Screening.

Anal Chem 2021 07 22;93(26):9258-9266. Epub 2021 Jun 22.

School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, U.K.

Incorporating safety data early in the drug discovery pipeline is key to reducing costly lead candidate failures. For a single drug development project, we estimate that several thousand samples per day require screening (<10 s per acquisition). While chromatography-based metabolomics has proven value at predicting toxicity from metabolic biomarker profiles, it lacks sufficiently high sample throughput. Read More

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Review of ultrasound combinations with hybrid and innovative techniques for extraction and processing of food and natural products.

Ultrason Sonochem 2021 Jun 11;76:105625. Epub 2021 Jun 11.

Avignon University, INRAE, UMR408, GREEN Extraction Team, 84000 Avignon, France. Electronic address:

Ultrasound has a significant effect on the rate of various processes in food, perfume, cosmetic, pharmaceutical, bio-fuel, materials, or fine chemical industries, despite some shortcomings. Combination with other conventional or innovative techniques can overcome these limitations, enhance energy, momentum and mass transfer, and has been successfully demonstrated in many recent studies. Various ultrasound combined hybrid and innovative techniques are systematically summarized in this review for the first time. Read More

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A one-year study of human milk oligosaccharide profiles in the milk of healthy UK mothers and their relationship to maternal FUT2 genotype.

Glycobiology 2021 Jun 15. Epub 2021 Jun 15.

Department of Food Science and Technology, University of California, Davis, USA.

Human milk oligosaccharides (HMOs) are indigestible carbohydrates with prebiotic, pathogen decoy, and immunomodulatory activities that are theorized to substantially impact infant health. The objective of this study was to monitor HMO concentrations over one year to develop a long-term longitudinal dataset. HMO concentrations in the breast milk of healthy lactating mothers of the Cambridge Baby Growth and Breastfeeding Study (CBGS-BF) were measured at birth, 2 weeks, 6 weeks, 3 months, 6 months and 12 months postpartum. Read More

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Quantitative Characterization of the Amount and Length of (1,3)-β-d-glucan for Functional and Mechanistic Analysis of Fungal (1,3)-β-d-glucan Synthase.

Bio Protoc 2021 Apr 20;11(8):e3995. Epub 2021 Apr 20.

Department of Biochemistry, Duke University School of Medicine, Durham, North Carolina, USA.

(1,3)-β-d-Glucan synthase (GS) is an essential enzyme for fungal cell wall biosynthesis that catalyzes the synthesis of (1,3)-β-d-glucan, a major and vital component of the cell wall. GS is a proven target of antifungal antibiotics including FDA-approved echinocandin derivatives; however, the function and mechanism of GS remain largely uncharacterized due to the absence of informative activity assays. Previously, a radioactive assay and reducing end modification have been used to characterize GS activity. Read More

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Alterations of urinary perchlorate levels in euthyroid postpubertal children with autism spectrum disorder.

J Trace Elem Med Biol 2021 Jun 5;68:126800. Epub 2021 Jun 5.

Department of Human Physiology, Medical University of Lublin, 20-080, Lublin, Poland.

Background: Perchlorates ClO() are known environmental and food contaminants that act as inhibitors of iodine uptake by the thyroid gland; however, information concerning their possible association with the development of autism spectrum disorder (ASD) is still missing. The current study is first presenting the alterations in perchlorate urine levels in euthyroid children with ASD.

Objectives: To examine urinary perchlorates and iodides in euthyroid children diagnosed with ASD, compared to age-, and BMI-matched neurotypical controls, and to verify the association between these two ions in ASD. Read More

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Thickness-Dependent Photoelectrochemical Water Splitting Properties of Self-Assembled Nanostructured LaFeO Perovskite Thin Films.

Nanomaterials (Basel) 2021 May 21;11(6). Epub 2021 May 21.

National Institute for Laser, Plasma and Radiation Physics, 077125 Magurele, Romania.

Tuning the intrinsic structural and stoichiometric properties by different means is used for increasing the green energy production efficiency of complex oxide materials. Here, we report on the formation of self-assembled nanodomains and their effects on the photoelectrochemical (PEC) properties of LaFeO (LFO) epitaxial thin films as a function of layer's thickness. The variation with the film's thickness of the structural parameters such as in-plane and out-of-plane crystalline coherence length and the coexistence of different epitaxial orientation-<100>SrTiO//<001> LFO, <100>SrTiO//<110> LFO and [110] LFO//[10] STO, as well as the appearance of self-assembled nanodomains for film's thicknesses higher than 14 nm, is presented. Read More

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Combining HPAEC-PAD, PGC-LC-MS, and 1D H NMR to Investigate Metabolic Fates of Human Milk Oligosaccharides in 1-Month-Old Infants: a Pilot Study.

J Agric Food Chem 2021 Jun 1;69(23):6495-6509. Epub 2021 Jun 1.

Laboratory of Food Chemistry, Wageningen University, P.O. Box 17, Wageningen 6700 AA, The Netherlands.

A solid-phase extraction procedure was optimized to extract 3-fucosyllactose and other human milk oligosaccharides (HMOs) from human milk samples separately, followed by absolute quantitation using high-performance anion-exchange chromatography-pulsed amperometric detection and porous graphitized carbon-liquid chromatography-mass spectrometry, respectively. The approach developed was applied on a pilot sample set of 20 human milk samples and paired infant feces collected at around 1 month postpartum. One-dimensional H nuclear magnetic resonance spectroscopy was employed on the same samples to determine the relative levels of fucosylated epitopes and sialylated (Neu5Ac) structural elements. Read More

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Results Multi-Laboratory Trial ISO/CD 22184-IDF/WD 244: Milk and Milk Products-Determination of the Sugar Contents-High-Performance Anion Exchange Chromatography Method with Pulsed Amperometric Detection.

J AOAC Int 2021 Jun;104(3):732-756

Eurofins Expertise Centre for Complex Carbohydrates and Chemistry, P.O. Box 766, 8440 AT Heerenveen, The Netherlands.

Background: In this international Multi-Laboratory Trial (MLT) the precision data and the accuracy of the ISO/CD 22184 IDF/WD 244 analytical method for the quantification of 6 different mono- and disaccharides (galactose, glucose, fructose, sucrose, lactose, and maltose) in milk and milk products with high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) are established.

Objective: Thirteen different laboratories participated (located in New Zealand, the United States, and Europe). The study was divided into two parts. Read More

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Towards a more complete glycome: Advances in ion chromatography-mass spectrometry (IC-MS) for improved separation and analysis of carbohydrates.

J Chromatogr B Analyt Technol Biomed Life Sci 2021 Jun 20;1175:122719. Epub 2021 Apr 20.

Thermo Fisher Scientific, 1228 Titan Way, Sunnyvale, CA 94086, USA.

To date, few tools are available for the analysis of the glycome without derivatization, a process which is known to introduce issues such as differential loss of sialic acid and incomplete labeling. We have previously reported the use of ion chromatography-mass spectrometry (IC-MS) to analyze native sialylated and sulfated glycans. Here, we introduce improvements to IC column technology, enabling the separation of neutral glycans while maintaining charge separation capabilities. Read More

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Modulation of the Sulfanylalkyl Acetate/Alcohol Ratio and Free Thiol Release from Cysteinylated and/or Glutathionylated Sulfanylalkyl Alcohols in Beer under Different Fermentation Conditions.

J Agric Food Chem 2021 Jun 21;69(21):6005-6012. Epub 2021 May 21.

Unité de Brasserie et des Industries Alimentaires, LIBST Institute, Faculté des Bioingénieurs, Université catholique de Louvain. Croix du Sud, 2 box L7.05.07, 1348 Louvain-la-Neuve, Belgium.

The occurrence of a substantial pool of cysteinylated and glutathionylated forms of polyfunctional thiols has been evidenced for several dual-purpose hop varieties, and so is the ability of yeast to release free thiols from these forms through fermentation. The present work aimed to investigate the effect of temperature, wort density, maturation time, and strain on the efficiency of free thiol release by yeasts. Model media at 12, 15, or 17°P were spiked with three cysteinylated (Cys-) or three glutathionylated (G-) sulfanylalkyl alcohols (Cys- or G-3-sulfanylpentan-1-ol, 3-sulfanyl-4-methylpentan-1-ol, and 3-sulfanylhexan-1-ol), fermented for 7 days at 18, 24, and 28 °C, and kept at 4 °C for varying number of days. Read More

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Real-Time Measurement of Cellobiose and Glucose Formation during Enzymatic Biomass Hydrolysis.

Anal Chem 2021 06 20;93(21):7732-7738. Epub 2021 May 20.

Biocatalysis and Biosensor Laboratory, Department of Food Science and Technology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria.

Enzymatic hydrolysis of lignocellulosic biomass for biofuel production relies on complex multi-enzyme ensembles. Continuous and accurate measurement of the released key products is crucial in optimizing the industrial degradation process and also investigating the activity and interaction between the involved enzymes and the insoluble substrate. Amperometric biosensors have been applied to perform continuous cellobiose measurements during the enzymatic hydrolysis of pure cellulose powders. Read More

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Underivatized amino acids detection by anion-exchange chromatography coupled to a nanostructured detector.

J Chromatogr B Analyt Technol Biomed Life Sci 2021 Jun 29;1174:122733. Epub 2021 Apr 29.

Analytical Chemistry Department, Institute of Chemistry, São Paulo State University (UNESP), Araraquara 14800-060, São Paulo State, Brazil; Bioenergy Research Institute, São Paulo State University (UNESP), Araraquara 14800-060, São Paulo State, Brazil.

This work reports the development of a fast and reliable amperometric sensor for the detection of amino acids. The detector was constructed using copper nanoparticles (CuNPs) supported on reduced graphene oxide (RGO) modified glassy carbon electrode (CuNPs-RGO/GCE) and based on the application of high performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD). Under optimized isocratic HPAEC-PAD conditions (using 40 mmol L NaOH as mobile phase, flow rate of 0. Read More

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Endolysosomal N-glycan processing is critical to attain the most active form of the enzyme acid alpha-glucosidase.

J Biol Chem 2021 Jan-Jun;296:100769. Epub 2021 May 8.

Discovery Science Division, Amicus Therapeutics, Inc., Philadelphia, Pennsylvania, USA. Electronic address:

Acid alpha-glucosidase (GAA) is a lysosomal glycogen-catabolizing enzyme, the deficiency of which leads to Pompe disease. Pompe disease can be treated with systemic recombinant human GAA (rhGAA) enzyme replacement therapy (ERT), but the current standard of care exhibits poor uptake in skeletal muscles, limiting its clinical efficacy. Furthermore, it is unclear how the specific cellular processing steps of GAA after delivery to lysosomes impact its efficacy. Read More

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Comparison of edible brown algae extracts for the inhibition of intestinal carbohydrate digestive enzymes involved in glucose release from the diet.

J Nutr Sci 2021 12;10:e5. Epub 2021 Jan 12.

Shannon Applied Biotechnology Centre, Institute of Technology Tralee, Tralee, Ireland.

Type II diabetes is considered the most common metabolic disorder in the developed world and currently affects about one in ten globally. A therapeutic target for the management of type II diabetes is the inhibition of α- glucosidase, an essential enzyme located at the brush border of the small intestinal epithelium. The inhibition of α-glucosidase results in reduced digestion of carbohydrates and a decrease in postprandial blood glucose. Read More

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January 2021

Nutritional and anti-nutritional properties of lentil () protein isolates prepared by pilot-scale processing.

Food Chem X 2021 Mar 7;9:100112. Epub 2021 Jan 7.

Department of Food Science, University of Copenhagen, Frederiksberg, Denmark.

Lentil () is a high-protein crop with a promising potential as a plant-based protein source for human nutrition. This study investigated nutritional and anti-nutritional properties of whole seed lentil flour (LF) compared to lentil protein isolates (LPIs) prepared in pilot-scale by isoelectric precipitation (LPI-IEP) and ultrafiltration (LPI-UF). Fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) profiles showed significant reductions in total galacto-oligosaccharides (GOS) contents by 58% and 91% in LPI-IEP and LPI-UF, respectively, compared to LF. Read More

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A novel dextrin produced by the enzymatic reaction of 6-α-glucosyltransferase. I. The effect of nonreducing ends of glucose with by α-1,6 bonds on the retrogradation inhibition of high molecular weight dextrin.

Biosci Biotechnol Biochem 2021 Jun;85(7):1737-1745

HAYASHIBARA CO., LTD., Okayama, Japan.

We prepared a high-molecular-weight modified dextrin (MWS-1000) from a partial hydrolysate of waxy corn starch with a weight average molecular weight of 1 × 106 (WS-1000) using Paenibacillus alginolyticus PP710 α-glucosyltransferase. The gel permeation chromatography showed that the weight average molecular weight of MWS-1000 was almost the same as that of WS-1000. The side chain lengths of WS-1000 and MWS-1000 after isomaltodextranase digestion were also shown to be similar to each other by high-performance anion exchange chromatography with pulsed amperometric detection. Read More

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Characterization of galacto-oligosaccharides using high-performance anion exchange chromatography-tandem mass spectrometry.

J Sep Sci 2021 Jun 22;44(11):2221-2233. Epub 2021 Apr 22.

Thermo Fisher Scientific, Sunnyvale, California, USA.

The analysis of complex oligosaccharide mixtures remains a challenge in the field of analytical chemistry. In this work, two commercial galacto-oligosaccharides samples were characterized using high-performance anion exchange chromatography coupled to mass spectrometry. The isomeric oligosaccharides were resolved with high resolution. Read More

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Saccharide analysis of onion outer epidermal walls.

Biotechnol Biofuels 2021 Mar 15;14(1):66. Epub 2021 Mar 15.

Center for Lignocellulose Structure and Formation, Department of Biology, Pennsylvania State University, 208 Mueller Lab, University Park, PA, 16802, USA.

Background: Epidermal cell walls have special structural and biological roles in the life of the plant. Typically they are multi-ply structures encrusted with waxes and cutin which protect the plant from dehydration and pathogen attack. These characteristics may also reduce chemical and enzymatic deconstruction of the wall for sugar analysis and conversion to biofuels. Read More

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Polymer Networks Synthesized from Poly(Sorbitol Adipate) and Functionalized Poly(Ethylene Glycol).

Gels 2021 Feb 20;7(1). Epub 2021 Feb 20.

Department of Chemistry, Martin Luther University Halle-Wittenberg, D-06120 Halle (Saale), Germany.

Polymer networks were prepared by Steglich esterification using poly(sorbitol adipate) (PSA) and poly(sorbitol adipate)--poly(ethylene glycol) mono methyl ether (PSA--mPEG) copolymer. Utilizing multi-hydroxyl functionalities of PSA, poly(ethylene glycol) (PEG) was first grafted onto a PSA backbone. Then the cross-linking of PSA or PSA--mPEG was carried out with disuccinyl PEG of different molar masses (Suc-PEG-Suc). Read More

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February 2021

Single-run HPLC Quantification of Plant Cell Wall Monosaccharides.

Bio Protoc 2020 Mar 5;10(5):e3546. Epub 2020 Mar 5.

Department of Biology, Institute of Molecular Plant Biology, ETH Zürich, Zürich, Switzerland.

The plant cell wall is a complex network of polysaccharides and proteins that provides strength and structural integrity to plant cells, as well as playing a vital role in growth, development, and defense response. Cell wall polysaccharides can be broadly grouped into three categories: cellulose, pectins, and hemicelluloses. Dynamic interactions between polysaccharides and cell wall-associated proteins contribute to regions of flexibility and rigidity within the cell wall, allowing for remodeling when necessary during growth, environmental adaptation, or stress response activation. Read More

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Determination of Bifidobacterial Carbohydrate Utilization Abilities and Associated Metabolic End Products.

Methods Mol Biol 2021 ;2278:117-129

School of Microbiology and APC Microbiome Ireland, University College Cork, Cork, Ireland.

Bifidobacteria are able to utilize a diverse range of host-derived and dietary carbohydrates, the latter of which include many plant-derived oligo- and polysaccharides. Different bifidobacterial strains may possess different carbohydrate utilization abilities. These metabolic abilities can be studied using classical bacterial growth assessment methods, such as measurement of changes in optical density or acidity of the culture in the presence of the particular carbohydrate to generate growth and acidification curves, respectively. Read More

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Organic biopolymers of venus clams: Collagen-related matrix in the bivalve shells with crossed-lamellar ultrastructure.

Biochem Biophys Rep 2021 Jul 12;26:100939. Epub 2021 Feb 12.

Department of Earth and Environmental Sciences, Macquarie University, Sydney, Australia.

Background: Biochemical studies and spectroscopic techniques have shown that chitin-silk fibroins are common in nacroprismatic bivalve shells. However, the nature of organic biopolymers in the less well studied shell architectures, such as crossed lamellar shells, remain unknown. Here, two venus shells, and , with crossed lamellar ultrastructure have been studied. Read More

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Altered immunoglobulin G glycosylation in patients with isolated hyperprolactinaemia.

PLoS One 2021 26;16(2):e0247805. Epub 2021 Feb 26.

Department of Clinical Chemistry, and Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden.

Prolactin is a peptide hormone produced in the anterior pituitary, which increase in several physiological and pathological situations. It is unclear if hyperprolactinaemia may affect glycosylation of immunoglobulin G (IgG). Twenty-five patients with hyperprolactinemia and 22 healthy control subjects were included in the study. Read More

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February 2021