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1.
J Dent ; 136: 104645, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37524196

RESUMO

OBJECTIVES: To identify the metabolomic differences in the saliva of healthy children versus children with active carious lesions and to estimate the predictive capacity of a model based on the salivary metabolomic profile. METHODS: A study of cases (n = 31) and controls (n = 37) was designed for children aged between 6 and 12 (mean age of the cases: 8.9; controls: 8.7). The said children attended public health centers in Valencia, Spain. Intraoral examinations were performed by a single examiner using ICDAS II diagnostic criteria. Unstimulated total saliva samples were analyzed by nuclear magnetic resonance (NMR) spectroscopy. RESULTS: The dft index for cases was 2.84 while it was 0.19 for the control group, the DMFT index was 1.13 and 0.11, respectively. The predictive model generated by the multivariate PLS-DA analysis projects a separation between the cases and the controls on the score chart with a predictive capacity and generating an area under the curve of 0.71. The metabolites: 3-methyl-2-oxovalerate, 3-hydroxybutyrate, lactate, acetone, citrate, ornithine, ethanolamine, taurine, proline, glycine, mannose, glucose, 1-6-Anhydro-ß-d-glucose and citraconate, are those that show greater significance in the model. In the controls, glycine (Cohen's d = 0.430) and glucose (Cohen's d = 0.560) present higher means compared to the cases. On the contrary, taurine (Cohen's d= -0.474) and mannose (Cohen's d= -0.456) show higher means in cases compared to controls. CONCLUSIONS: Our findings show a difference in the salivary metabolomic profiles, specifically in the groups of saccharides and amino acids, suggesting an association of these with the level of caries risk. CLINICAL SIGNIFICANCE: The results reported in the present study reinforce the use of salivary metabolomics as a research method for the search for salivary biomarkers that allow the evaluation of caries risk in patients. Furthermore, it brings us closer to a personalized medicine that will help in dental caries prevention strategies.


Assuntos
Cárie Dentária , Humanos , Criança , Cárie Dentária/diagnóstico , Manose/análise , Manose/metabolismo , Saliva/química , Metabolômica , Glucose/metabolismo , Glicina/análise , Glicina/metabolismo , Taurina/análise , Taurina/metabolismo
2.
Int J Biol Macromol ; 227: 1001-1014, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36464192

RESUMO

Galactomannans are reserve carbohydrates in legume plants and are primarily extracted from their seeds. They contain galactose side chains throughout the mannose backbone and have unique features such as emulsifying, thickening, and gelling together with biodegradability, biocompatibility, and non-toxicity, which make them an appealing material. Guar gum and locust bean gum mainly are used in all galactomannan needed applications. Nonetheless, tara gum and fenugreek gum have also attracted considerable attention in recent decades. Despite the increased usage of galactomannans in the textile-related fields in recent years, there is no review article published yet. To fill this gap and to demonstrate the striking and increasing importance of galactomannans, a concise summary of the properties of common galactomannans and their comparisons is given first, followed by an account of recent developments and applications of galactomannans in the textile-related fields. The associated potential opportunities are also provided at the end of this review.


Assuntos
Galactanos , Gomas Vegetais , Gomas Vegetais/química , Galactanos/química , Mananas/química , Galactose/química , Manose/análise , Sementes/química , Têxteis
3.
Molecules ; 27(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36558014

RESUMO

The extraction, characterization and antioxidant activity of polysaccharides from Choerospondias axillaris leaves were investigated in the present study. Two purified polysaccharide fractions, CALP-1 and CALP-2, were isolated from crude Choerospondias axillaris leaf polysaccharides (CALP) by DEAE-52 cellulose chromatography and Sephadex G-100 column chromatography. The characteristics of CAL-1 and CALP-2 were determined by using High-performance Gel Permeation Chromatography (HPGPC), High-Performance Anion-Exchange Chromatography, HPAEC (HPAEC-PAD) and Fourier transform infrared spectroscopy (FTIR). CALP-1 with molecular weight of 11.20 KDa was comprised of Rhamnose, Arabinose, Galactose, Glucose, Xylose, Mannose and galacturonic acid in a molar ratio of 5.16:2.31:5.50:27.18:1.00:0.76:1.07. CAL-2 with molecular weight of 8.03 KDa consisted of Rhamnose, Arabinose, Galactose, Glucose, and galacturonic acid at a ratio of 1.38:3.63:18.84:8.28:1.45. FTIR revealed that CALP-1 and CALP-2 were acidic polysaccharides. The antioxidant activity of crude CALP, CALP-1 and CALP-2 was evaluated in vitro. The fraction CALP-2 was demonstrated to be of polysaccharide nature containing a large percentage of Galactose but no Xylose and Mannose. The antioxidant activity assays showed that CALP-1 and CALP-2 exhibited antioxidant and scavenging activities on hydroxyl and DPPH radicals in vitro. Compared with pure polysaccharide, crude CALP exhibited stronger anti-oxidant activities. These results will provide a better understanding of Choerospondias axillaris leaf polysaccharide and promote the potential applications of Choerospondias axillaris leaf polysaccharide in the pharmacological field and as a natural antioxidant.


Assuntos
Antioxidantes , Galactose , Antioxidantes/química , Galactose/análise , Manose/análise , Ramnose/análise , Arabinose/análise , Peso Molecular , Cromatografia em Gel , Polissacarídeos/química , Folhas de Planta/química , Glucose/análise
4.
Molecules ; 27(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36296474

RESUMO

Although the fruit of Ficus tikoua Bur. has been consumed by montanic people in China for centuries, its chemical and biological composition was still unclear. A series of comprehensive investigations on its chemical constituents and bioactivities were carried out for the first time. As a result, six compounds were isolated and identified as the main components in this fruit. GC-MS analysis of the lipid components demonstrated that Ficus tikoua Bur. fruit contains some wholesome constituents such as fatty acids, vitamins, triterpenoids, and phytosterols. The fatty acids are mainly composed of linolenic acid (61.27%) and linoleic acid (22.79%). Furthermore, this fruit contains a relative high content of crude protein (9.41 ± 0.03%), total amino acids (9.28%), and total polyphenols (0.86 ± 0.01 g/100 g). The analysis of monosaccharide composition showed that the total polysaccharide mainly consists of glucose, glucuronic acid, xylose, arabinose, mannose, galactose, galacturonic acid, and rhamnose. The polysaccharide, polyphenol, water, ethanol, and flavonoid extracts exhibited prominent antioxidant activity determined by ABTS, DPPH, and FRAPS methods. Meanwhile, the total polysaccharide exhibited significant immunomodulatory effect by enhancing the release of cytokines and expression of iNOS and COX-2 in RAW264.7 cells, significantly decreasing the expression of c-Jun and p65 proteins in the cytoplasm; increasing the translocation of c-Jun and p65 to the nucleus; and regulating the phosphorylation level of Akt, PI3K, and PDK1 in the PI3K/AKT signaling pathway. This study proved that the fruit of F. tikoua is a reliable source of functional food.


Assuntos
Ficus , Fitosteróis , Triterpenos , Humanos , Ficus/química , Antioxidantes/química , Frutas/química , Polifenóis/farmacologia , Polifenóis/análise , Ciclo-Oxigenase 2 , Galactose/análise , Manose/análise , Arabinose/análise , Ramnose/análise , Xilose/análise , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Polissacarídeos/química , Flavonoides/análise , Monossacarídeos/análise , Citocinas/análise , Água/análise , Lipídeos/análise , Vitaminas/análise , Triterpenos/análise , Fitosteróis/análise , Glucose/análise , Etanol/análise , Aminoácidos/análise , Glucuronatos , Ácidos Linolênicos , Ácidos Linoleicos/análise
5.
Chem Biodivers ; 19(10): e202200156, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36039474

RESUMO

Alsophila spinulosa, as a rare tree fern with potential medicinal value, has attracted extensive attention. Herein, the physicochemical properties, antioxidant and anti-aging activities of polysaccharide from A. spinulosa leaf (ALP) were investigated. ALP was composed of galactose, arabinose, glucose, rhamnose, galacturonic acid, mannose, and fucose. (1→), (1→6), and (1→2) bond types were the primary glycosidic bond in ALP. Surprisingly, ALP displayed the wonderful activity of antioxidant and anti-aging, including excellent scavenging ability against DPPH and ABTS radicals in vitro; prolonging the life span, improving activity of antioxidative enzymes (SOD and CAT), and decreasing the level of ROS, MDA in Caenorhabditis elegans. Meanwhile, ALP promoted DAF-16 to move into the nuclear. Overall, our results illustrated that ALP could be further developed as a functional food ingredient.


Assuntos
Gleiquênias , Ingredientes de Alimentos , Traqueófitas , Animais , Caenorhabditis elegans , Antioxidantes/química , Espécies Reativas de Oxigênio/análise , Fucose/análise , Galactose , Manose/análise , Arabinose/análise , Ramnose , Polissacarídeos/farmacologia , Polissacarídeos/química , Folhas de Planta/química , Envelhecimento , Superóxido Dismutase , Ingredientes de Alimentos/análise , Glucose/análise
6.
J Sep Sci ; 45(18): 3422-3430, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35839084

RESUMO

Saccharides, especially anhydro sugars present in atmospheric aerosols, can be used as tracers to track sources of atmospheric aerosols. High-performance anion-exchange chromatography with pulsed amperometric detection is a commonly used technique for determining these saccharides, but the reported methods suffer from three drawbacks. First, to achieve separation of the complete set of atmospheric saccharides, run times are very long, typically longer than 60 minutes. Second, some methods require two columns to achieve the desired separation. Finally, in an era when electrolytic eluent preparation allows for excellent precision and accuracy, these methods require manually prepared eluents, which can lead to separation inconsistency for closely eluting analytes. These drawbacks make existing methods difficult to automate. To address this issue, we developed a fast method that uses only a single column for separation and electrolytically generated eluent that resolves 12 key atmospheric aerosol saccharides in 20 minutes. The resolved saccharides include anhydro sugars (levoglucosan, galactosan, and mannosan), sugar alcohols (erythritol, xylitol, and mannitol), and mono-/disaccharides (arabinose, galactose, glucose, mannose, fructose, and sucrose). To our knowledge, this report is the first instance of achieving such a significant reduction in run time with good resolution for this set of saccharides.


Assuntos
Galactose , Manose , Aerossóis/análise , Ânions , Arabinose , Carboidratos/análise , Cromatografia/métodos , Dissacarídeos , Eritritol , Frutose , Galactose/análise , Glucose/análise , Manitol , Manose/análise , Manose/química , Sacarose , Álcoois Açúcares , Açúcares , Xilitol
7.
Fungal Genet Biol ; 160: 103686, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35306147

RESUMO

The formation of a cell wall is vital for the survival and growth of a fungal cell. Fungi express members of the GH76 family of α-1,6-mannanases which play an important role in cell wall biogenesis. In this report we characterize the Neurospora crassa DFG-5 α-1,6-mannanase and demonstrate that it binds to the α-1,6-mannose backbone of an N-linked galactomannan found on cell wall glycoproteins. We show that DFG-5 has an enzymatic activity and provide evidence that it processes the α-1,6-mannose backbone of the N-linked galactomannan. Site-directed mutagenesis and complementation experiments show that D116 and D117 are located at the DFG-5 active site. D76 and E130, which are located in a groove on the opposite side of the protein, are also important for enzyme function. Cell wall glycoproteins co-purify with DFG-5 demonstrating a specific association between DFG-5 and cell wall glycoproteins. DFG-5 is able to discriminate between cell wall and secreted glycoproteins, and does not bind to the N-linked galactomannans present on secreted glycoproteins. DFG-5 plays a key role in targeting extracellular glycoproteins to their final destinations. By processing the galactomannans on cell wall proteins, DFG-5 targets them for cell wall incorporation by lichenin transferases. The N-linked galactomannans on secreted proteins are not processed by DFG-5, which targets these proteins for release into the extracellular medium.


Assuntos
Neurospora crassa , Parede Celular/metabolismo , Glicoproteínas/genética , Glicoproteínas/metabolismo , Manose/análise , Manose/metabolismo
8.
Nat Struct Mol Biol ; 29(3): 190-193, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35273390

RESUMO

Glycoprotein 2 (GP2) and uromodulin (UMOD) filaments protect against gastrointestinal and urinary tract infections by acting as decoys for bacterial fimbrial lectin FimH. By combining AlphaFold2 predictions with X-ray crystallography and cryo-EM, we show that these proteins contain a bipartite decoy module whose new fold presents the high-mannose glycan recognized by FimH. The structure rationalizes UMOD mutations associated with kidney diseases and visualizes a key epitope implicated in cast nephropathy.


Assuntos
Adesinas Bacterianas , Fímbrias Bacterianas , Adesinas Bacterianas/genética , Cristalografia por Raios X , Proteínas de Fímbrias/química , Proteínas de Fímbrias/genética , Proteínas de Fímbrias/metabolismo , Fímbrias Bacterianas/química , Fímbrias Bacterianas/metabolismo , Proteínas Ligadas por GPI , Humanos , Manose/análise , Uromodulina/análise , Uromodulina/química , Uromodulina/metabolismo
9.
Int J Biol Macromol ; 205: 76-89, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35181328

RESUMO

Polysaccharides coded as CP were extracted from Athyrium Multidentatum (Doll.) Ching and then fractionated into five fractions (FP-1, FP-2, FP-3, FP-4 and FP-5). A purified polysaccharide designated as FP-3-4 was prepared from FP-3 by Sephadex G-100 column chromatography. Chemical analysis disclosed that CP and these fractions were heteropolysaccharides and mainly composed of glucose, galactose, arabinose, mannose, rhamnose, xylose, fucose, ribose and uronic acid with different molar ratios. They presented different images of SEM. FP-3-4 was highly branched polymers with sixteen types of linkages. The in vitro immunomodulatory results stated that CP and these fractions could promote macrophage proliferation, enhance macrophage phagocytosis and increase the production of NO, TNF-α, IFN-γ, IL-1ß, IL-6, IL-10 and IL-2, indicating remarkable immune enhancement activities. RNA sequencing analysis revealed that CP and FP-3 induced macrophage activation mainly through MAPK and alternative NF-κΒ signaling pathways via CD14/TLR4 and Dectin-2 receptors, which were verified by RT-qPCR and western blot.


Assuntos
Fucose , Polissacarídeos , Animais , Arabinose , Galactose/análise , Manose/análise , Camundongos , Polissacarídeos/química , Polissacarídeos/farmacologia , Células RAW 264.7
10.
Food Funct ; 12(19): 9327-9338, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34606556

RESUMO

The extracellular polysaccharide of Morchella esculenta cultivated under submerged fermentation was extracted. A single polysaccharide was purified through DEAE-Cellulose 52 and Sephadex G 100, and named as MEP 2a. The molecular weight of MEP 2a was determined by HPGPC and it is about 1391.5 kDa. MEP 2a is composed of mannose and glucose as the monosaccharide unit with a molar ratio of 8.15 : 1.07. The main polysaccharide chemical structure was analyzed by 1D and 2D NMR. Methylation and NMR analysis revealed that the backbone of MEP 2a consists of 1,3,4-linked-Manp, 1,2-linked-Manp and 1,6-linked-Glcp. 1D and 2D NMR results indicated that the main chain is based on →1)-ß-D-Glcp-(6→, →1)-α-D-Manp-(3,4→, →1)-α-D-Manp-(2→) and the branch chain is composed of α-D-Manp-(1→, →1)-ß-D-Glcp-(6→ and α-D-Glcp-(1→). MEP 2a promoted the phagocytosis function and secretion of NO, IL-1ß, IL-6 and TNF-α of macrophages. In the present study, the chemical structure and immunomodulatory ability of an extracellular polysaccharide of Morchella esculenta was investigated which guarantees further research studies and promising applications.


Assuntos
Ascomicetos/metabolismo , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/farmacologia , Imunomodulação , Animais , Ascomicetos/química , Configuração de Carboidratos , Citocinas/metabolismo , Fermentação , Polissacarídeos Fúngicos/biossíntese , Polissacarídeos Fúngicos/isolamento & purificação , Glucose/análise , Sistema de Sinalização das MAP Quinases , Macrófagos/imunologia , Macrófagos/metabolismo , Manose/análise , Metilação , Camundongos , Peso Molecular , Óxido Nítrico/metabolismo , Fagocitose , Células RAW 264.7
11.
Food Funct ; 12(20): 9855-9865, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34664579

RESUMO

Finger citron pomace is a cheap and renewable by-product of the citrus processing industry, representing up to 60% of the fruit biomass. In this study, a pectinase-based and ultrasonic-assisted method was firstly used to extract pectic oligosaccharides (POS) from finger citron pomace. Using the orthogonal experiment design (OED), the maximum conversion rate of up to 64.5% from pomace to POS was obtained under the extraction conditions of 0.25 mg mL-1 pectinase and 50 mg mL-1 pectin at 45 °C and pH 4.5 for 2 h. The extracted POS was then fractionated and purified to homogeneous oligosaccharides (FCPOS-1) with a molecular weight of 2.15 kDa, and the analyses of monosaccharide composition, FTIR, NMR and ESI-MS indicated that FCPOS-1 consisted of GalA and a small amount of mannose, galactose and arabinose. Multiple antioxidant activity assays in vitro revealed that FCPOS-1 possessed remarkable antioxidant properties, especially scavenging activity against DPPH radicals up to 94.07%. FCPOS-1 has the potential to be an effective natural antioxidant for applications in the food and pharmaceutical industries.


Assuntos
Antioxidantes/farmacologia , Citrus/química , Oligossacarídeos/isolamento & purificação , Oligossacarídeos/farmacologia , Pectinas/isolamento & purificação , Poligalacturonase/metabolismo , Arabinose/análise , Fracionamento Químico/métodos , Frutas/química , Galactose/análise , Humanos , Espectroscopia de Ressonância Magnética/métodos , Manose/análise , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
12.
Carbohydr Polym ; 272: 118411, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34420705

RESUMO

In this work we have efficiently extracted and characterized pectin from different tissues of astringent (AS) and non-astringent (NAS) persimmon fruits (peel, pulp, whole fruit) for the first time. The highest pectin extraction (≥7.2%) was carried out at 80 °C, 120 min with 1.5% sodium citrate in peel of both AS and NAS persimmon samples. All persimmon pectins showed a molecular weight and galacturonic acid content upper than 328 kDa and 78%, respectively, indicating their suitability as food ingredient. Pectin extracted from AS pulp and peel tissues exhibited an enriched structure in rhamnose and arabinose, whereas the opposite behavior was observed in NAS persimmon whole fruit samples. Remarkably, both pulp tissues (AS and NAS) presented the highest levels of glucose and mannose, non-pectic carbohydrates. In addition, techno-functional assessment (zeta potential, particle size, apparent viscosity, gelation) showed the suitability of the persimmon pectins for a broad range of industrial applications.


Assuntos
Diospyros/química , Frutas/química , Pectinas/análise , Arabinose/análise , Glucose/análise , Ácidos Hexurônicos/análise , Manose/análise , Peso Molecular , Tamanho da Partícula , Ramnose/análise , Reologia/métodos , Citrato de Sódio/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Viscosidade
13.
Molecules ; 26(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34361796

RESUMO

Meat is a rich source of energy that provides high-value animal protein, fats, vitamins, minerals and trace amounts of carbohydrates. Globally, different types of meats are consumed to fulfill nutritional requirements. However, the increasing burden on the livestock industry has triggered the mixing of high-price meat species with low-quality/-price meat. This work aimed to differentiate different meat samples on the basis of metabolites. The metabolic difference between various meat samples was investigated through Nuclear Magnetic Resonance spectroscopy coupled with multivariate data analysis approaches like principal component analysis (PCA) and orthogonal partial least square-discriminant analysis (OPLS-DA). In total, 37 metabolites were identified in the gluteal muscle tissues of cow, goat, donkey and chicken using 1H-NMR spectroscopy. PCA was found unable to completely differentiate between meat types, whereas OPLS-DA showed an apparent separation and successfully differentiated samples from all four types of meat. Lactate, creatine, choline, acetate, leucine, isoleucine, valine, formate, carnitine, glutamate, 3-hydroxybutyrate and α-mannose were found as the major discriminating metabolites between white (chicken) and red meat (chevon, beef and donkey). However, inosine, lactate, uracil, carnosine, format, pyruvate, carnitine, creatine and acetate were found responsible for differentiating chevon, beef and donkey meat. The relative quantification of differentiating metabolites was performed using one-way ANOVA and Tukey test. Our results showed that NMR-based metabolomics is a powerful tool for the identification of novel signatures (potential biomarkers) to characterize meats from different sources and could potentially be used for quality control purposes in order to differentiate different meat types.


Assuntos
Contaminação de Alimentos/análise , Carne/análise , Metaboloma , Metabolômica/métodos , Aminoácidos/análise , Animais , Bovinos , Galinhas , Colina/análise , Creatina/análise , Equidae , Contaminação de Alimentos/prevenção & controle , Cabras , Humanos , Ácido Láctico/análise , Análise dos Mínimos Quadrados , Espectroscopia de Ressonância Magnética , Manose/análise , Análise Multivariada , Análise de Componente Principal , Especificidade da Espécie
14.
Bioengineered ; 12(1): 4420-4431, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34308749

RESUMO

Raman spectroscopy was applied to an aqueous solution containing D-mannose and D-glucose at a fixed dry matter content. The Raman measurement apparatus was adapted online at the industrial scale to monitor a bioprocess including an epimerization reaction. Online Raman spectroscopy and deconvolution techniques were successfully applied to monitor in real time the D-mannose and D-glucose concentrations using the Raman shifts at 960 cm-1 and 974 cm-1 respectively. The two anomeric forms, α and ß of D-mannose in the pyranose conformation were quantified. In silico analysis of vibrational frequencies and Raman intensities of hydrated structure of D-mannose and D-glucose in the pyranose form for α and ß anomers were carried out using a two-step procedure. First molecular dynamics was used to generate the theoretical carbohydrates' structures keeping the experimental dry matter content, then quantum mechanics was used to compute the Raman frequencies and intensities. Computed vibrational frequencies are in satisfactory agreement with the experimental spectra considering a hydration shell approach. Raman intensities are qualitatively in accordance with the experimental data. The interpretation of Raman frequencies and intensities led to acceptable results regarding the current possible structures of D-mannose and D-glucose in aqueous solution. Online Raman spectroscopy coupled with in silico approaches such as quantum mechanics and molecular dynamics methodology is proved to be a valuable tool to quantify the carbohydrates and stereoisomers content in complex aqueous mixtures. This methodology offers a new way to monitor any bioprocesses that encounter aqueous mixtures of D-glucose and D-mannose.


Assuntos
Glucose/química , Manose/química , Análise Espectral Raman/métodos , Glucose/análise , Manose/análise , Simulação de Dinâmica Molecular , Vibração , Água
15.
Mikrochim Acta ; 188(8): 252, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34255200

RESUMO

A competitive strategy for glycan determination on cell surface with organic electrochemical transistors (OECTs) has been developed. The carboxylic multi-wall carbon nanotubes were firstly immobilized on the gate interface to cross-link the specific monose with adipic dihydrazide as the linker, which could then competitively recognize horseradish peroxidase (HRP)-labeled lectin with the target monose on the cell surface. The HRP captured on the gate interface through the affinity of lectin to monose finally catalyzed the reduction of hydrogen peroxide to produce the output current signal for detection of cell surface monose under the optimal gate voltage of 0.9 V. Using mannose and galactose groups as the target models, HRP-labeled concanavalin A and peanut agglutinin were used to competitively recognize these groups on both cell surface and gate interface, respectively. The amounts of mannose and galactose on HeLa cells were measured to be 3.41 × 108 and 2.92 × 108 molecules per cell, respectively. The changes of the mannose and galactose expressions upon external stimulation were also observed with the proposed biosensors, which showed consistent results with flow cytometric analysis, indicating that the OECT-based biosensor is suitable for analysis of different glycan expressions on cell surface. Graphical abstract.


Assuntos
Membrana Celular/química , Peroxidase do Rábano Silvestre/química , Lectinas/química , Nanotubos de Carbono/química , Polissacarídeos/análise , Técnicas Biossensoriais , Concanavalina A/química , Técnicas Eletroquímicas , Galactose/análise , Células HeLa , Humanos , Peróxido de Hidrogênio/química , Manose/análise , Oxirredução , Polissacarídeos/genética
16.
Development ; 148(10)2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-34015094

RESUMO

Plant growth, morphogenesis and development involve cellular adhesion, a process dependent on the composition and structure of the extracellular matrix or cell wall. Pectin in the cell wall is thought to play an essential role in adhesion, and its modification and cleavage are suggested to be highly regulated so as to change adhesive properties. To increase our understanding of plant cell adhesion, a population of ethyl methanesulfonate-mutagenized Arabidopsis were screened for hypocotyl adhesion defects using the pectin binding dye Ruthenium Red that penetrates defective but not wild-type (WT) hypocotyl cell walls. Genomic sequencing was used to identify a mutant allele of ELMO1 which encodes a 20 kDa Golgi membrane protein that has no predicted enzymatic domains. ELMO1 colocalizes with several Golgi markers and elmo1-/- plants can be rescued by an ELMO1-GFP fusion. elmo1-/- exhibits reduced mannose content relative to WT but no other cell wall changes and can be rescued to WT phenotype by mutants in ESMERALDA1, which also suppresses other adhesion mutants. elmo1 describes a previously unidentified role for the ELMO1 protein in plant cell adhesion.


Assuntos
Arabidopsis/embriologia , Adesão Celular/genética , Adesão Celular/fisiologia , Complexo de Golgi/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Complexo de Golgi/genética , Hipocótilo/citologia , Hipocótilo/genética , Manose/análise , Proteínas de Membrana/genética , Metiltransferases/genética , Pectinas/metabolismo
17.
Reprod Fertil Dev ; 33(5): 349-362, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33602388

RESUMO

Cadmium (Cd) is a heavy metal related to a decrease in sperm parameters. The transit of spermatozoa through the epididymis is necessary to generate changes in the sperm membrane, such as the assembly of various carbohydrates that are added to the spermatazoan's surface to prepare it for successful fertilisation of the oocyte. No studies have yet analysed whether Cd alters the presence and distribution of these carbohydrates. We aimed to evaluate the changes induced by Cd in the distribution pattern of N-acetylglucosamine, sialic acid, mannose and fucose on the sperm membrane in the epididymis (e.g. caput, corpus, cauda) and if it alters the epididymal epithelium. Male Wistar pups were treated with Cd doses (0.125, 0.25 and 0.5mg/kg) on postnatal days 1-49. At postnatal day 90, they were humanely killed, sperm samples were obtained from the epididymis and tissue samples were taken for histological analysis. Cd concentrations in the blood and epididymis increased in proportion to the dose administered and decreased the serum testosterone levels and sperm quality. Histological analysis revealed alterations in the epithelium in all Cd-treated groups. Cd altered the distribution patterns of carbohydrates and fluorescence indices. All these alterations affected the structure and functioning of sperm.


Assuntos
Cádmio/administração & dosagem , Carboidratos/análise , Membrana Celular/química , Epididimo/crescimento & desenvolvimento , Maturação do Esperma/efeitos dos fármacos , Espermatozoides/crescimento & desenvolvimento , Acetilglucosamina/análise , Animais , Cádmio/análise , Membrana Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Epididimo/química , Epididimo/citologia , Fucose/análise , Masculino , Manose/análise , Ácido N-Acetilneuramínico , Ratos , Ratos Wistar , Espermatozoides/efeitos dos fármacos , Espermatozoides/ultraestrutura , Testosterona/sangue
18.
Carbohydr Polym ; 256: 117394, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483006

RESUMO

In the present work a galactomannan extract of low protein residue (< 1.3 % wt dry basis) was isolated from alfalfa (Medicago sativa L.) seed endosperm meal. The alfalfa gum (AAG) comprised primarily mannose and galactose at a ratio of 1.18:1, had a molecular weight of 2 × 106 Da and a radius of gyration of 48.7 nm. The average intrinsic viscosity of the dilute AAG dispersions calculated using the modified Mark-Houwink, Huggins and Kraemer equations was 9.33 dLg-1 at 25 °C. The critical overlap concentration was estimated at 0.306 % whereas the concentration dependence of specific viscosity for the dilute and semi-dilute regimes was ∝ C2.3 and C4.2, respectively. The compliance to the Cox-Merz rule was satisfied at 1% of AAG, whereas a departure from superimposition was observed at higher concentrations. Viscoelasticity measurements demonstrated that AAG dispersions exhibit a predominant viscous character at 1 % wt, whereas a weak gel-like behaviour was reached at AAG concentrations ≥3 %.


Assuntos
Mananas/química , Medicago sativa/química , Gomas Vegetais/química , Sementes/química , Elasticidade , Endosperma/química , Galactose/análise , Concentração de Íons de Hidrogênio , Manose/análise , Peso Molecular , Oscilometria , Reologia , Resistência ao Cisalhamento , Açúcares/química , Trigonella/química , Ácidos Urônicos/química , Viscosidade
19.
Genet Test Mol Biomarkers ; 24(9): 562-568, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32762555

RESUMO

Aims: Nondiabetic patients were studied to determine whether modest elevations in plasma mannose may be associated with a greater incidence of coronary artery disease (CAD). Materials and Methods: Plasma insulin, mannose, glucose, hexokinase 1-2, GLUT1-GLUT4 levels, and serum mannose phosphate isomerase enzyme levels were evaluated with respect to subsequent CAD using records from 120 nondiabetic CAD patients and 120 healthy volunteers. CAD was identified from myocardial infarction and new diagnoses of angina. Results: Of 120 nondiabetic CAD patients studied, their plasma GLUT4 and HK1 levels were significantly lower than those of the control group. In addition, a significant increase in plasma mannose levels was found in the patient group compared to the control group. Conclusion: Our findings showed that elevated baseline mannose levels in plasma are associated with an increased risk of CAD over time.


Assuntos
Doença da Artéria Coronariana/metabolismo , Manose/análise , Idoso , Biomarcadores/sangue , Glicemia/análise , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/genética , Feminino , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 4/genética , Hexoquinase/genética , Humanos , Masculino , Manose/sangue , Manose/genética , Pessoa de Meia-Idade , Infarto do Miocárdio/metabolismo , Plasma/química , Fatores de Risco , Turquia
20.
Int J Biol Macromol ; 162: 116-126, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32565299

RESUMO

In this study, a novel water-soluble polysaccharide (PVLP-1) was extracted and purified from Sacha inchi (Plukenetia volubilis L.) seeds and the structure, antioxidant and immunomodulatory activity of PVLP-1 were investigated. PVLP-1 (144 kDa) consisted of glucose (69.76%), mannose (14.86%), arabinose (10.53%), galactose (2.42%), ribose (1.23%), rhamnose (0.27%) and xylose (0.93%). PVLP-1 displayed characteristic polysaccharide bands in Fourier transform NMR spectra and infrared. The primary structure of PVLP-1 was a heteropolysaccharide with a backbone of (1 â†’ 6)-linked glucose, sidechains of (1 â†’ 4)-linked mannose, (1 â†’ 4)-linked glucose and (1 â†’ 3, 6)-linked mannose and a residue unit of →1)-linked arabinose as revealed the methylation analysis. PVLP-1 possessed good water-holding capacity (WHC), oil-holding capacity (OHC) and antioxidant capacities. Besides, PVLP-1 induced the proliferation of RAW264.7 cell and enhanced the expression of inflammatory cytokines IL-6, TNF-alpha(TNF-α) and IL-1 beta (IL-1ß). The present study indicated that PVLP-1 possessed immune-enhancing bioactivities and could be functional food or adjuvant drug to improve biological immunity of immunodeficiency diseases and hypoimmunity.


Assuntos
Adjuvantes Imunológicos/farmacologia , Antioxidantes/farmacologia , Proliferação de Células/efeitos dos fármacos , Euphorbiaceae/química , Polissacarídeos/análise , Polissacarídeos/farmacologia , Sementes/química , Animais , Arabinose/análise , Sobrevivência Celular/efeitos dos fármacos , Carboidratos da Dieta/metabolismo , Carboidratos da Dieta/farmacologia , Galactose/análise , Glucose/análise , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Manose/análise , Camundongos , Fagocitose/efeitos dos fármacos , Óleos de Plantas/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Células RAW 264.7 , Ramnose/análise , Ribose/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Fator de Necrose Tumoral alfa/metabolismo , Água/química , Xilose/análise
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