In the shadow of SARS-CoV-2, influenza seems to be an innocent virus, although new zoonotic influenza viruses evolved by mutations may lead to severe pandemics. According to WHO, there is an urgent need for better antiviral drugs. Blocking viral hemagglutinin with multivalent N-acetylneuraminic acid derivatives is a promising approach to prevent influenza infection. Moreover, dual inhibition of both hemagglutinin and neuraminidase may result in a more powerful effect. Since both viral glycoproteins can bind to neuraminic acid, we have prepared three series of amphiphilic self-assembling 2-thio-neuraminic acid derivatives constituting aggregates in aqueous medium to take advantage of their multivalent effect. One of the series was prepared by the azide-alkyne click reaction, and the other two by the thio-click reaction to yield neuraminic acid derivatives containing lipophilic tails of different sizes and an enzymatically stable thioglycosidic bond. Two of the three bis-octyl derivatives produced proved to be active against influenza viruses, while all three octyl derivatives bound to hemagglutinin and neuraminidase from H1N1 and H3N2 influenza types.
- MeSH
- chřipka lidská * farmakoterapie MeSH
- hemaglutininové glykoproteiny viru chřipky metabolismus MeSH
- hemaglutininy farmakologie MeSH
- kyselina N-acetylneuraminová farmakologie metabolismus MeSH
- kyseliny neuraminové MeSH
- lidé MeSH
- neuraminidasa metabolismus MeSH
- virus chřipky A, podtyp H1N1 * MeSH
- virus chřipky A, podtyp H3N2 MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
BackgroundTimely treatment with neuraminidase inhibitors (NAI) can reduce severe outcomes in influenza patients.AimWe assessed the impact of antiviral treatment on in-hospital deaths of laboratory-confirmed influenza patients in 11 European Union countries from 2010/11 to 2019/20.MethodsCase-based surveillance data from hospitalised patients with known age, sex, outcome, ward, vaccination status, timing of antiviral treatment, and hospitalisation were obtained. A mixed effect logistic regression model using country as random intercept was applied to estimate the adjusted odds ratio (aOR) for in-hospital death in patients treated with NAIs vs not treated.ResultsOf 19,937 patients, 31% received NAIs within 48 hours of hospital admission. Older age (60-79 years aOR 3.0, 95% CI: 2.4-3.8; 80 years 8.3 (6.6-10.5)) and intensive care unit admission (3.8, 95% CI: 3.4-4.2) increased risk of dying, while early hospital admission after symptom onset decreased risk (aOR 0.91, 95% CI: 0.90-0.93). NAI treatment initiation within 48 hours and up to 7 days reduced risk of dying (0-48 hours aOR 0.51, 95% CI: 0.45-0.59; 3-4 days 0.59 (0.51-0.67); 5-7 days 0.64 (0.56-0.74)), in particular in patients 40 years and older (e.g. treatment within 48 hours: 40-59 years aOR 0.43, 95% CI: 0.28-0.66; 60-79 years 0.50 (0.39-0.63); ≥80 years 0.51 (0.42-0.63)).ConclusionNAI treatment given within 48 hours and possibly up to 7 days after symptom onset reduced risk of in-hospital death. NAI treatment should be considered in older patients to prevent severe outcomes.
- MeSH
- antivirové látky terapeutické užití MeSH
- chřipka lidská * farmakoterapie epidemiologie MeSH
- guanidiny terapeutické užití MeSH
- inhibitory enzymů terapeutické užití MeSH
- lidé MeSH
- mortalita v nemocnicích MeSH
- neuraminidasa MeSH
- oseltamivir * terapeutické užití MeSH
- senioři MeSH
- výsledek terapie MeSH
- zanamivir terapeutické užití MeSH
- Check Tag
- lidé MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
Saccharides form one of the major constituents of biological macromolecules in living organisms. Many biological processes including protein folding, stability, immune response and receptor activation are regulated by glycosylation. In this work, we optimized a capillary electrophoresis method with capacitively coupled contactless conductivity detection for the separation of eight monosaccharides commonly found in glycoproteins, namely D-glucose, D-galactose, D-mannose, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, D-fucose, N-acetylneuraminic acid, and D-xylose. A highly alkaline solution of 50 mM sodium hydroxide, 22.5 mM disodium phosphate, and 0.2 mM CTAB (pH 12.4) was used as a background electrolyte in a 10 μm id capillary. To achieve baseline separation of all analytes, a counter-directional pressure of -270 kPa was applied during the separation. The limits of detection of our method were below 7 μg/ml (i.e., 1.5 pg or 1 mg/g protein) and the limits of quantification were below 22 μg/ml (i.e., 5 pg or 3 mg/g protein). As a proof of concept of our methodology, we performed an analysis of monosaccharides released from fetuin glycoprotein by acid hydrolysis. The results show that, when combined with an appropriate pre-concentration technique, the developed method can be used as a monosaccharide profiling tool in glycoproteomics and complement the routinely used LC-MS/MS analysis.
- MeSH
- acetylgalaktosamin MeSH
- acetylglukosamin MeSH
- cetrimonium MeSH
- chromatografie kapalinová MeSH
- elektroforéza kapilární metody MeSH
- elektrolyty chemie MeSH
- fetuiny MeSH
- fosfáty MeSH
- fukosa MeSH
- galaktosa MeSH
- glukosa MeSH
- glykoproteiny chemie MeSH
- hydroxid sodný MeSH
- kyselina N-acetylneuraminová * MeSH
- mannosa MeSH
- monosacharidy * analýza MeSH
- tandemová hmotnostní spektrometrie MeSH
- xylosa MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The composition of a sample solvent has a crucial impact on separations in hydrophilic interaction liquid chromatography (HILIC). In this short communication, we studied the effect of an organic modifier in the sample solvent on the solubility of different tryptic glycopeptides of hemopexin and haptoglobin proteins. The results showed that the solubility of glycopeptides in solvents with a high acetonitrile content depends on the type of attached N-glycan. We observed lower solubility in larger glycans attached to the same peptide backbone, and we demonstrated that glycopeptides containing sialic acids precipitate more readily than those without sialic acid. Therefore, the sample solvent composition in HILIC must be carefully optimized for accurate quantitative data collection and for adequate separation.
- MeSH
- acetonitrily chemie MeSH
- glykopeptidy analýza chemie izolace a purifikace MeSH
- hydrofobní a hydrofilní interakce MeSH
- kyselina N-acetylneuraminová chemie MeSH
- polysacharidy chemie MeSH
- rozpouštědla chemie MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- Publikační typ
- časopisecké články MeSH
Sialic acid (SA), a family of acetylated derivatives of neuraminic acid, an acute phase reactant by itself. It usually occurs as a terminal component at the non-reducing end of carbohydrate chains of glycoproteins and glycolipids. SA participates in multiple physiological functions, such as cell-to-cell interactions, cell migration and proliferation. Diabetes mellitus (DM) is a chronic metabolic disorder characterized by rise in blood glucose level. Periodontitis is a chronic inflammatory disease of the periodontal tissue, leading to destruction of bone surrounding the tooth and ultimately tooth loss. There is a two way relationship between diabetes mellitus and periodontitis. Periodontitis is the sixth complication of diabetes along with retinopathy, nephropathy, neuropathy, macrovascular disease, and altered wound healing. Inflammatory mediators like interleukin-6 and tumor necrosis factor-alpha produced during periodontal inflammation can interfere with the actions of insulin receptors and worsen the glycemic control of diabetic patients. Periodontitis is a major cause of tooth loss, affecting over 300 million people and bacteria associated with periodontitis are also linked with systemic problems like endocarditis, atherosclerosis. Recent work has highlighted a major role for the host sugar sialic acid in the biofilm physiology and host-pathogen interactions of T. forsithya, a key periodontal pathogen. There exists a need for a biomarker, for early detection of disease evolution and more robust therapy efficacy measurements. Serum sialic acids were estimated in Indian population by diphenylamine method and Thiobarbituric acid method. The average values were 68 ± 2.6 mg percent by DPA method and 56 ± 5 mg percent by TBA (thiobarbituric acid assay) method. Age and sex showed no influence on serum sialic acid level. Objectives of the present study was to compare (TSSA) level in healthy subjects, subjects with (CMP) with and without (NIDDM) and its effect on non-surgical periodontal therapy. In the present study, the participants were divided into three groups: Group A, B and C. Group A consists of systemically healthy subjects, Group B consists of subjects with (CMP) while Group C consists of subjects with (CMP) with (NIDDM) and results of this study indicated that, at baseline, there were significant differences between Group A, B and Group C with respect to all the clinical parameters, including (GI), (OHI-S), (PPD), (CAL), (TSSA) and (HbA1c) levels. Thus (TSSA) level could be considered as novel biomarker in the progression of periodontal disease and diabetic status. Periodontitis could be considered as a potential, modifiable, and independent risk factor for the development of diabetes. Early detection of elevated (TSSA) level may help in interpreting the progression of periodontitis, risk of development of diabetes mellitus in future and also to prevent complications.
- MeSH
- biologické markery krev MeSH
- diabetes mellitus 2. typu krev komplikace MeSH
- dospělí MeSH
- komplikace diabetu krev MeSH
- kyselina N-acetylneuraminová krev MeSH
- lidé středního věku MeSH
- lidé MeSH
- parodontitida krev komplikace terapie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Human milk is a source of glycoconjugates, sialylated forms of which enrich the newborn immature immune system and are crucial for their proper development and well-being. Here, we analyzed the expression of α2,3-/α2,6-sialylated glycotopes on skim milk glycoproteins over lactation. Milk samples were analyzed by lectin-blotting using α2,3- and α2,6- sialic acid specific Maackia amurensis (MAA) and Sambucus nigra (SNA) lectins and sialyl- and asialyl-T antigen specific Artocarpus integrifolia (Jacalin) and Arachis hypogaea (PNA) lectins. The reactivities of MAA, SNA, Jacalin and PNA with milk glycoproteins showed that they are heavily decorated with α2,3-/α2,6-linked sialic acid and sialyl-T antigen and to a lesser degree with asialyl-T antigen. Despite individual differences of particular glycoproteins, a sharp and significant decline of α2,6-sialylated glycotopes and sialyl-T antigens and a weaker but significant decrease of α2,3-sialylated glycotopes and asialyl-T antigens on milk glycoproteins during milk maturation was observed. The expression of α2,3-/α2,6-sialylated glycotopes, sialyl- and asialyl-T antigens corresponds to milk maturation but differs in relation to the analyzed glycoprotein. Sialylated milk glycoproteins are considered as a part of innate immunity provided to neonates. Further investigations are needed to understand if they may be useful in milk banking to control the biochemical quality of milk.
- Klíčová slova
- sialyl-T antigen,
- MeSH
- antigeny povrchové MeSH
- časové faktory MeSH
- chemické techniky analytické MeSH
- glykoproteiny * chemie MeSH
- kyseliny sialové analýza chemie MeSH
- laktace MeSH
- lektiny chemie MeSH
- lidé MeSH
- mateřské mléko * chemie MeSH
- muciny * chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
In recent decades, it has become clear that most of human proteins are glycosylated and that protein glycosylation plays an important role in health and diseases. At present, simple, fast and inexpensive methods are sought for clinical applications and particularly for improved diagnostics of various diseases, including cancer. We propose a label- and reagent-free electrochemical method based on chronopotentiometric stripping (CPS) analysis and a hanging mercury drop electrode for the detection of interaction of sialylated protein biomarker a prostate specific antigen (PSA) with two important lectins: Sambucus nigra agglutinin (SNA) and Maackia amurensis agglutinin (MAA). Incubation of PSA-modified electrode with specific SNA lectin resulted in an increase of CPS peak H of the complex as compared to this peak of individual PSA. By adjusting polarization current and temperature, PSA-MAA interaction can be either eliminated or distinguished from the more abundant PSA-SNA complex. CPS data were in a good agreement with the data obtained by complementary methods, namely surface plasmon resonance and fluorescent lectin microarray. It can be anticipated that CPS will find application in glycomics and proteomics.
BACKGROUND: Neuraminidase inhibitors are effective for the treatment of acute uncomplicated influenza. However, there is an unmet need for intravenous treatment for patients admitted to hospital with severe influenza. We studied whether intravenous zanamivir was a suitable treatment in this setting. METHODS: In this international, randomised, double-blind, double-dummy, phase 3 trial, we recruited patients aged 16 years or older with severe influenza admitted to 97 hospitals from 26 countries. We randomly assigned patients (1:1:1 stratified by symptom onset ≤4 days or 5-6 days) to receive 300 mg or 600 mg intravenous zanamivir, or standard-of-care (75 mg oral oseltamivir) twice a day for 5-10 days; patients were followed up for 28 days. The randomisation schedule, including stratification, was generated using GlaxoSmithKline's RandAll software. Patients, site study staff, and sponsor were masked to study treatment. The primary endpoint was time to clinical response-a composite of vital sign stabilisation and hospital discharge-in the influenza-positive population. The trial was powered to show an improvement of 1·5 days or greater with 600 mg intravenous zanamivir. Pharmacokinetic, safety, and virology endpoints were also assessed. This trial is registered with ClinicalTrials.gov, number NCT01231620. FINDINGS: Between Jan 15, 2011, and Feb 12, 2015, 626 patients were randomly assigned to receive 300 mg intravenous zanamivir (n=201), 600 mg intravenous zanamivir (n=209), or 75 mg oral oseltamivir (n=205) twice a day; 11 patients discontinued the study before receiving any study treatment. 488 (78%) of 626 patients had laboratory-confirmed influenza. Compared with a median time to clinical response of 5·14 days in the 600 mg intravenous zanamivir group, the median time to clinical response was 5·87 days (difference of -0·73 days, 95% CI -1·79 to 0·75; p=0·25) in the 300 mg intravenous zanamivir group and 5·63 days (difference of -0·48 days, 95% CI -2·11 to 0·97; p=0·39) in the oseltamivir group. Four patients with influenza A/H1N1pdm09 in the oseltamivir group developed H275Y resistance mutations. Adverse events were reported in 373 (61%) of treated patients and were similar across treatment groups; the most common adverse events (300 mg intravenous zanamivir, 600 mg intravenous zanamivir, oseltamivir) were diarrhoea (10 [5%], 15 [7%], 14 [7%]), respiratory failure (11 [5%], 14 [7%], 11 [5%]), and constipation (7 [3%], 13 [6%], 10 [5%]). 41 (7%) treated patients died during the study (15 [7%], 15 [7%], 11 [5%]); the most common causes of death were respiratory failure and septic shock. INTERPRETATION: Time to clinical response to intravenous zanamivir dosed at 600 mg was not superior to oseltamivir or 300 mg intravenous zanamivir. All treatments had a similar safety profile in hospitalised patients with severe influenza. FUNDING: GlaxoSmithKline.
- MeSH
- antivirové látky aplikace a dávkování MeSH
- aplikace orální MeSH
- chřipka lidská farmakoterapie MeSH
- dospělí MeSH
- dvojitá slepá metoda MeSH
- hospitalizace * MeSH
- intravenózní podání MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- oseltamivir aplikace a dávkování MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- výsledek terapie MeSH
- zanamivir aplikace a dávkování MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- klinické zkoušky, fáze III MeSH
- multicentrická studie MeSH
- práce podpořená grantem MeSH
- randomizované kontrolované studie MeSH
BACKGROUND: Human milk oligosaccharides (HMOs) are one of the major glycan source of the infant gut microbiota. The two species that predominate the infant bifidobacteria community, Bifidobacterium longum subsp. infantis and Bifidobacterium bifidum, possess an arsenal of enzymes including α-fucosidases, sialidases, and β-galactosidases to metabolise HMOs. Recently bifidobacteria were obtained from the stool of six month old Kenyan infants including species such as Bifidobacterium kashiwanohense, and Bifidobacterium pseudolongum that are not frequently isolated from infant stool. The aim of this study was to characterize HMOs utilization by these isolates. Strains were grown in presence of 2'-fucosyllactose (2'-FL), 3'-fucosyllactose (3'-FL), 3'-sialyl-lactose (3'-SL), 6'-sialyl-lactose (6'-SL), and Lacto-N-neotetraose (LNnT). We further investigated metabolites formed during L-fucose and fucosyllactose utilization, and aimed to identify genes and pathways involved through genome comparison. RESULTS: Bifidobacterium longum subsp. infantis isolates, Bifidobacterium longum subsp. suis BSM11-5 and B. kashiwanohense strains grew in the presence of 2'-FL and 3'- FL. All B. longum isolates utilized the L-fucose moiety, while B. kashiwanohense accumulated L-fucose in the supernatant. 1,2-propanediol (1,2-PD) was the major metabolite from L-fucose fermentation, and was formed in equimolar amounts by B. longum isolates. Alpha-fucosidases were detected in all strains that degraded fucosyllactose. B. longum subsp. infantis TPY11-2 harboured four α-fucosidases with 95-99 % similarity to the type strain. B. kashiwanohense DSM 21854 and PV20-2 possessed three and one α-fucosidase, respectively. The two α-fucosidases of B. longum subsp. suis were 78-80 % similar to B. longum subsp. infantis and were highly similar to B. kashiwanohense α-fucosidases (95-99 %). The genomes of B. longum strains that were capable of utilizing L-fucose harboured two gene regions that encoded enzymes predicted to metabolize L-fucose to L-lactaldehyde, the precursor of 1,2-PD, via non-phosphorylated intermediates. CONCLUSION: Here we observed that the ability to utilize fucosyllactose is a trait of various bifidobacteria species. For the first time, strains of B. longum subsp. infantis and an isolate of B. longum subsp. suis were shown to use L-fucose to form 1,2-PD. As 1,2-PD is a precursor for intestinal propionate formation, bifidobacterial L-fucose utilization may impact intestinal short chain fatty acid balance. A L-fucose utilization pathway for bifidobacteria is suggested.
- MeSH
- alfa-L-fukosidasa klasifikace genetika metabolismus MeSH
- beta-galaktosidasa metabolismus MeSH
- Bifidobacterium longum enzymologie genetika metabolismus MeSH
- Bifidobacterium enzymologie genetika metabolismus MeSH
- DNA bakterií genetika MeSH
- feces mikrobiologie MeSH
- fukosa metabolismus MeSH
- genom bakteriální MeSH
- kojenec MeSH
- kyseliny mastné těkavé metabolismus MeSH
- kyseliny sialové metabolismus MeSH
- laktosa analogy a deriváty metabolismus MeSH
- lidé MeSH
- mateřské mléko metabolismus MeSH
- metabolické sítě a dráhy MeSH
- oligosacharidy metabolismus MeSH
- propylenglykol metabolismus MeSH
- RNA ribozomální 16S genetika MeSH
- sekvence nukleotidů MeSH
- střeva mikrobiologie MeSH
- trisacharidy metabolismus MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Bile acids have been implicated in cholestatic liver damage, primarily due to their detergent effect on membranes and induction of oxidative stress. Gangliosides can counteract these harmful effects by increasing the rigidity of the cytoplasmic membrane. Induction of haem oxygenase (HMOX) has been shown to protect the liver from increased oxidative stress. The aim of this study was to determine the changes in the synthesis and distribution of liver gangliosides following bile duct ligation (BDL), and to assess the effects of HMOX both on cholestatic liver injury and ganglioside metabolism. Compared to controls, BDL resulted in a significant increase in total as well as complex gangliosides and mRNA expression of corresponding glycosyltransferases ST3GalV, ST8SiaI and B3GalTIV. A marked shift of GM1 ganglioside from the intracellular compartment to the cytoplasmic membrane was observed following BDL. Induction of oxidative stress by HMOX inhibition resulted in a further increase of these changes, while HMOX induction prevented this effect. Compared to BDL alone, HMOX inhibition in combination with BDL significantly increased the amount of bile infarcts, while HMOX activation decreased ductular proliferation. We have demonstrated that cholestasis is accompanied by significant changes in the distribution and synthesis of liver gangliosides. HMOX induction results in attenuation of the cholestatic pattern of liver gangliosides, while HMOX inhibition leads to the opposite effect.
- MeSH
- biologické markery metabolismus MeSH
- cholestáza enzymologie genetika metabolismus patologie MeSH
- cytoplazma metabolismus MeSH
- gangliosidy metabolismus MeSH
- hemová oxygenasa (decyklizující) metabolismus MeSH
- intracelulární membrány metabolismus MeSH
- játra enzymologie metabolismus patologie MeSH
- kyselina N-acetylneuraminová metabolismus MeSH
- ligace MeSH
- messenger RNA genetika metabolismus MeSH
- oxidační stres * MeSH
- potkani Wistar MeSH
- proliferace buněk MeSH
- tělesná hmotnost MeSH
- velikost orgánu MeSH
- žlučové cesty patologie MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
