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1.
Biochemistry (Mosc) ; 89(1): 148-158, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38467551

RESUMO

Gestational diabetes mellitus (GDM) is a risk factor for both mother and fetus/neonate during and after the pregnancy. Inconsistent protocols and cumbersome screening procedures warrant the search for new and easily accessible biomarkers. We investigated a potential of serum N-glycome to differentiate between healthy pregnant women (n = 49) and women with GDM (n = 53) using a lectin-based microarray and studied the correlation between the obtained data and parameters of glucose and lipid metabolism. Four out of 15 lectins used were able to detect the differences between the control and GDM groups in fucosylation, terminal galactose/N-acetylglucosamine (Gal/GlcNAc), presence of Galα1,4Galß1,4Glc (Gb3 antigen), and terminal α2,3-sialylation with AUC values above 60%. An increase in the Gb3 antigen and α2,3-sialylation correlated positively with GDM, whereas the amount of fucosylated glycans correlated negatively with the content of terminal Gal/GlcNAc. The content of GlcNAc oligomers correlated with the highest number of blood analytes, indices, and demographic characteristics, but failed to discriminate between the groups. The presence of terminal Gal residues correlated positively with the glucose levels and negatively with the LDL levels in the non-GDM group only. The results suggest fucosylation, terminal galactosylation, and the presence of Gb3 antigen as prediction markers of GDM.


Assuntos
Diabetes Gestacional , Recém-Nascido , Gravidez , Feminino , Humanos , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/metabolismo , Prognóstico , Glicosilação , Lectinas/metabolismo , Glucose
2.
J Enzyme Inhib Med Chem ; 39(1): 2301772, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38221792

RESUMO

The viral genome of the SARS-CoV-2 coronavirus, the aetiologic agent of COVID-19, encodes structural, non-structural, and accessory proteins. Most of these components undergo rapid genetic variations, though to a lesser extent the essential viral proteases. Consequently, the protease and/or deubiquitinase activities of the cysteine proteases Mpro and PLpro became attractive targets for the design of antiviral agents. Here, we develop and evaluate new bis(benzylidene)cyclohexanones (BBC) and identify potential antiviral compounds. Three compounds were found to be effective in reducing the SARS-CoV-2 load, with EC50 values in the low micromolar concentration range. However, these compounds also exhibited inhibitory activity IC50 against PLpro at approximately 10-fold higher micromolar concentrations. Although originally developed as PLpro inhibitors, the comparison between IC50 and EC50 of BBC indicates that the mechanism of their in vitro antiviral activity is probably not directly related to inhibition of viral cysteine proteases. In conclusion, our study has identified new potential noncytotoxic antiviral compounds suitable for in vivo testing and further improvement.


Assuntos
COVID-19 , Cisteína Proteases , Humanos , SARS-CoV-2 , Cisteína Endopeptidases/metabolismo , Proteínas não Estruturais Virais/química , Antivirais/farmacologia , Antivirais/química , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Simulação de Acoplamento Molecular
3.
Int J Mol Sci ; 25(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38731843

RESUMO

Chronic kidney disease (CKD) is a global health concern affecting approximately one billion individuals worldwide. End-stage kidney disease (ESKD), the most severe form of CKD, is often accompanied by anemia. Peritoneal dialysis (PD), a common treatment for ESKD, utilizes the peritoneum for solute transfer but is associated with complications including protein loss, including transferrin (Tf) a key protein involved in iron transport. This study investigated Tf characteristics in ESKD patients compared to healthy individuals using lectin microarray, spectroscopic techniques and immunocytochemical analysis to assess Tf interaction with transferrin receptors (TfRs). ESKD patients exhibited altered Tf glycosylation patterns, evidenced by significant changes in lectin reactivity compared to healthy controls. However, structural analyses revealed no significant differences in the Tf secondary or tertiary structures between the two groups. A functional analysis demonstrated comparable Tf-TfR interaction in both PD and healthy samples. Despite significant alterations in Tf glycosylation, structural integrity and Tf-TfR interaction remained preserved in PD patients. These findings suggest that while glycosylation changes may influence iron metabolism, they do not impair Tf function. The study highlights the importance of a glucose-free dialysis solutions in managing anemia exacerbation in PD patients with poorly controlled anemia, potentially offering a targeted therapeutic approach to improve patient outcomes.


Assuntos
Falência Renal Crônica , Receptores da Transferrina , Transferrina , Humanos , Transferrina/metabolismo , Glicosilação , Falência Renal Crônica/terapia , Falência Renal Crônica/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Receptores da Transferrina/metabolismo , Diálise Peritoneal , Idoso , Adulto , Ferro/metabolismo
4.
Sensors (Basel) ; 23(12)2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37420529

RESUMO

Protein-carbohydrate interactions happen to be a crucial facet of biology, discharging a myriad of functions. Microarrays have become a premier choice to discern the selectivity, sensitivity and breadth of these interactions in a high-throughput manner. The precise recognition of target glycan ligands among the plethora of others is central for any glycan-targeting probe being tested by microarray analyses. Ever since the introduction of the microarray as an elemental tool for high-throughput glycoprofiling, numerous distinct array platforms possessing different customizations and assemblies have been developed. Accompanying these customizations are various factors ushering variances across array platforms. In this primer, we investigate the influence of various extrinsic factors, namely printing parameters, incubation procedures, analyses and array storage conditions on the protein-carbohydrate interactions and evaluate these factors for the optimal performance of microarray glycomics analysis. We hereby propose a 4D approach (Design-Dispense-Detect-Deduce) to minimize the effect of these extrinsic factors on glycomics microarray analyses and thereby streamline cross-platform analyses and comparisons. This work will aid in optimizing microarray analyses for glycomics, minimize cross-platform disparities and bolster the further development of this technology.


Assuntos
Líquidos Corporais , Glicômica , Glicômica/métodos , Análise em Microsséries/métodos , Polissacarídeos , Ligantes
5.
Int J Mol Sci ; 24(10)2023 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-37240090

RESUMO

Changes in protein glycosylation are associated with most biological processes, and the importance of glycomic analysis in the research of disorders is constantly increasing, including in the neurodevelopmental field. We glycoprofiled sera in 10 children with attention-deficit hyperactivity disorder (ADHD) and 10 matching healthy controls for 3 types of samples: whole serum, sera after depletion of abundant proteins (albumin and IgG), and isolated IgG. The analytical methods used were a lectin-based glycoprotein microarray enabling high-throughput glycan analysis and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) as a standard method for the identification of glycan structures. For microarray analysis, the samples printed on microarray slides were incubated with biotinylated lectins and detected using the fluorescent conjugate of streptavidin by a microarray scanner. In the ADHD patient samples, we found increased antennary fucosylation, decreased di-/triantennary N-glycans with bisecting N-acetylglucosamine (GlcNAc), and decreased α2-3 sialylation. The results obtained by both independent methods were consistent. The study's sample size and design do not allow far-reaching conclusions to be drawn. In any case, there is a strong demand for a better and more comprehensive diagnosis of ADHD, and the obtained results emphasize that the presented approach brings new horizons to studying functional associations of glycan alterations in ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Criança , Humanos , Glicoproteínas/química , Polissacarídeos/química , Lectinas/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Imunoglobulina G/metabolismo
6.
Int J Mol Sci ; 25(1)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38203400

RESUMO

Blue C-phycocyanin (C-PC), the major Spirulina protein with innumerable health-promoting benefits, is an attractive colourant and food supplement. A crucial obstacle to its more extensive use is its relatively low stability. This study aimed to screen various food-derived ligands for their ability to bind and stabilise C-PC, utilising spectroscopic techniques and molecular docking. Among twelve examined ligands, the protein fluorescence quenching revealed that only quercetin, coenzyme Q10 and resveratrol had a moderate affinity to C-PC (Ka of 2.2 to 3.7 × 105 M-1). Docking revealed these three ligands bind more strongly to the C-PC hexamer than the trimer, with the binding sites located at the interface of two (αß)3 trimers. UV/VIS absorption spectroscopy demonstrated the changes in the C-PC absorption spectra in a complex with quercetin and resveratrol compared to the spectra of free protein and ligands. Selected ligands did not affect the secondary structure content, but they induced changes in the tertiary protein structure in the CD study. A fluorescence-based thermal stability assay demonstrated quercetin and coenzyme Q10 increased the C-PC melting point by nearly 5 °C. Our study identified food-derived ligands that interact with C-PC and improve its thermal stability, indicating their potential as stabilising agents for C-PC in the food industry.


Assuntos
Proteína C , Spirulina , Animais , Ubiquinona , Antioxidantes/farmacologia , Ficocianina , Simulação de Acoplamento Molecular , Quercetina , Resveratrol/farmacologia , Aditivos Alimentares , Decapodiformes , Suplementos Nutricionais
7.
Expert Rev Proteomics ; 17(4): 257-273, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32427033

RESUMO

INTRODUCTION: The importance of biomarkers for pharmaceutical drug development and clinical diagnostics is more significant than ever in the current shift toward personalized medicine. Biomarkers have taken a central position either as companion markers to support drug development and patient selection, or as indicators aiming to detect the earliest perturbations indicative of disease, minimizing therapeutic intervention or even enabling disease reversal. Protein biomarkers are of particular interest given their central role in biochemical pathways. Hence, capabilities to analyze multiple protein biomarkers in one assay are highly interesting for biomedical research. AREAS COVERED: We here review multiple methods that are suitable for robust, high throughput, standardized, and affordable analysis of protein biomarkers in a multiplex format. We describe innovative developments in immunoassays, the vanguard of methods in clinical laboratories, and mass spectrometry, increasingly implemented for protein biomarker analysis. Moreover, emerging techniques are discussed with potentially improved protein capture, separation, and detection that will further boost multiplex analyses. EXPERT COMMENTARY: The development of clinically applied multiplex protein biomarker assays is essential as multi-protein signatures provide more comprehensive information about biological systems than single biomarkers, leading to improved insights in mechanisms of disease, diagnostics, and the effect of personalized medicine.


Assuntos
Biomarcadores/química , Proteômica/métodos , Animais , Biomarcadores/análise , Humanos , Imunoensaio/métodos , Espectrometria de Massas/métodos
8.
Proteomics ; 16(24): 3096-3104, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27883257

RESUMO

Prostate cancer (PCa) is one of the most common newly diagnosed cancers among men and we focused on its traditional biomarker, prostate-specific antigen (PSA), using targeted glycomics-based strategies. The aberrant glycosylation pattern of PSA may serve as a valuable tool for improving PCa diagnosis including its early-stage. In this study, we evaluated the usability of two techniques, surface plasmon resonance and protein microarray assay, for the study and characterization of interactions of PSA (both free and complexed) with six lectins (SNA, ConA, RCA, AAL, WGA and MAA II). The information on the character of such interactions is important for the application of lectins as prospective bioreceptors for biomarker glycoprofiling in a follow-up biosensing assays. SPR as well as established bioanalytical techniques allowed determination of KD values of PSA-lectin interactions in a more reliable way than protein microarray. The protein microarray method did not allow accurate quantification of KD values. However, the features of a microarray approach, such as speed and costs, enabled the screening and estimation of the nature of lectin-glycan biomarker interaction in an effective and time-saving way. All of the tested lectins interacted with commercial PSA standard isolated from healthy persons, except MAA II which reacted only very weakly.


Assuntos
Lectinas/metabolismo , Antígeno Prostático Específico/metabolismo , Humanos , Masculino , Análise Serial de Proteínas , Ligação Proteica , Ressonância de Plasmônio de Superfície
9.
Glycoconj J ; 33(5): 717-24, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27085877

RESUMO

The high complexity of glycome, the repertoire of glycans expressed in a cell or in an organism, is difficult to analyze and the use of new technologies has accelerated the progress of glycomics analysis. In the last decade, the microarray approaches, and in particular glycan and lectin microarrays, have provided new insights into evaluation of cell glycosylation status. Here we present a cell microarray method based on cell printing on microarray slides for the analysis of the glycosylation pattern of the cell glycocalyx. In order to demonstrate the reliability of the developed method, the glycome profiles of equine native uncultured mural granulosa cells (uGCs) and in vitro cultured mural granulosa cells (cGCs) were determined and compared. The method consists in the isolation of GCs, cell printing into arrays on microarray slide, incubation with a panel of biotinylated lectins, reaction with fluorescent streptavidin and signal intensity detection by a microarray scanner. Cell microarray technology revealed that glycocalyx of both uGCs and cGCs contains N-glycans, sialic acid terminating glycans, N-acetylglucosamine and O-glycans. The comparison of uGCs and cGCs glycan signals indicated an increase in the expression of sialic acids, N-acetylglucosamine, and N-glycans in cGCs. Glycan profiles determined by cell microarray agreed with those revealed by lectin histochemistry. The described cell microarray method represents a simple and sensitive procedure to analyze cell surface glycome in mammalian cells.


Assuntos
Glicocálix/metabolismo , Células da Granulosa/metabolismo , Lectinas/química , Análise Serial de Tecidos/instrumentação , Análise Serial de Tecidos/métodos , Animais , Feminino , Células da Granulosa/citologia , Cavalos
10.
Analyst ; 141(23): 6444-6448, 2016 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-27767199

RESUMO

Lateral flow assays (LFAs) enable the simple and rapid detection and quantification of analytes and is popular for point-of-care (PoC), point-of-use and outdoor testing applications. LFAs typically depend on antibody or nucleic acid based recognition. We present the innovative concept of a LFA using lectins in the role of the biorecognition element. Lectins are a special kind of glycan-binding protein and the lectin-based LFA herein described was developed for the determination of the glycosylation of free prostate specific antigen (PSA). PSA is routinely used as a biomarker of prostate cancer (PCa) and the glycosylation status of PSA is a more specific marker of disease progress than only the PSA level. Using the lectin-based LFA we were able to detect α-2,6 sialic acid present in fPSA using Sambucus nigra (SNA) lectin. As a negative control, we employed Maackia amurensis lectin II (MAA II) which specifically binds α-2,3 sialic acid. The novel approach presented here can be applied to a wide range of biomarkers that have a significant impact on clinical diagnosis and prognosis, providing an alternative to standard lectin-based assays. The assay uses commercial components and is easily performed by applying a sample to the sampling pad on the lectin-based LFA strip, with results obtained within 10 minutes.


Assuntos
Lectinas/química , Ácido N-Acetilneuramínico/análise , Antígeno Prostático Específico/análise , Biomarcadores Tumorais/análise , Glicosilação , Humanos , Masculino , Estudo de Prova de Conceito , Neoplasias da Próstata/diagnóstico , Sambucus/química
11.
Biotechnol Appl Biochem ; 63(4): 457-64, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26075587

RESUMO

Glycosylation is co- and posttranslational modifications affecting proteins. The glycopattern changes are associated with changes in biological function and are involved in many diseases including cancer. We present the lectin-based protein microarray method enabling determination of differences in protein glycosylation. The method involves isolation of targeted protein from samples by immunoprecipitation, spotting of protein from multiple samples into arrays on a microarray slide, incubation with set of biotinylated lectins, the reaction with fluorescent conjugate of streptavidin, and detection of fluorescent intensities by microarray scanner. Lectin-based protein microarray was applied in investigation of differences in alpha-2-macroglobulin (α2M) glycosylation isolated from sera samples of healthy persons and patients with colorectal cancer (CC). From 14 lectins used in analysis, statistically significant differences (Student's t-test, P < 0.05) between two groups of samples (persons without cancer and CC patients) were found for 5 of them. α2M molecules isolated from sera of CC patients have higher content of α2,6 sialic acid, N-acetylglucosamine and mannose residues, and tri-/tetraantennary complex type high-mannose N-glycans. A novel lectin-based protein microarray developed and described can serve as a suitable analytical technique for sensitive, simple, fast, and high-throughput determination of differences in protein glycosylation isolated from serum or other samples.


Assuntos
Neoplasias Colorretais/sangue , Neoplasias Colorretais/metabolismo , Lectinas/metabolismo , Análise Serial de Proteínas/métodos , alfa-Macroglobulinas/metabolismo , Idoso , Estudos de Casos e Controles , Feminino , Glicosilação , Humanos , Masculino , Pessoa de Meia-Idade
12.
Gen Physiol Biophys ; 35(4): 497-510, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27763330

RESUMO

In P-gp-positive cell variants obtained from L1210 cells either by selection with vincristine (L1210/R) or by transfection with the human gene encoding P-gp (L1210/T), we have previously described cross-resistance to tunicamycin (TNM), a protein N-glycosylation inhibitor. Here we studied whether this cross-resistance also underlies P-gp-positive variants of human acute myeloid leukemia cells (AML) derived from SKM-1 and MOLM-13 cells (SKM-1/VCR, SKM-1/LEN, MOLM-13/VCR) by selection with vincristine (VCR) and lenalidomide (LEN). While SKM-1/LEN cells were P-gp positive, no P-gp was detected in MOLM-13/LEN cells. P-gp-positive cells could be repeatedly passaged in medium containing TNM. In contrast, more than 90% of P-gp-negative cells were entering and progressing through cell death mechanisms after the third passage in medium containing TNM. Combined apoptosis/necrosis cell death was detected in L1210 cells after exposure to TNM. Passaging of P-gp-negative AML cells in medium containing TNM induced preferentially apoptosis. Damage to P-gp-negative cells induced with TNM was associated with arrest in the G1 phase of the cell cycle. P-gp-positive leukemia cells differed from P-gp-negative cells in the composition of plasma membrane glycoproteins, which we monitored with the aid of different lectins. The application of TNM to cells induced additional changes in membrane-linked glycosides.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Apoptose/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Leucemia/tratamento farmacológico , Tunicamicina/administração & dosagem , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Glicosilação/efeitos dos fármacos , Humanos , Leucemia/patologia , Resultado do Tratamento
13.
J Cancer Res Clin Oncol ; 150(2): 96, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38372785

RESUMO

BACKGROUND: Bladder cancer (BC) belongs to the most frequent cancer types. The diagnostic process is still long and costly, with a high percentage of false-positive or -negative results. Due to the cost and lack of effectiveness, older methods need to be supplemented or replaced by a newer more reliable method. In this regard, proteins and glycoproteins pose high potential. METHODS: We performed an online search in PubMed/Medline, Scopus, and Web of Science databases to find relevant studies published in English up until May 2023. If applicable, we set the AUC threshold to 0.90 and sensitivity/specificity (SN/SP) to 90%. FINDINGS: Protein and glycoprotein biomarkers are a demonstrably viable option in BC diagnostics. Cholinesterase shows promise in progression-free survival. BLCA-4, ORM-1 along with HTRA1 in the detection of BC. Matrix metallopeptidase 9 exhibits potential for stratification of muscle-invasive subtypes with high negative predictive value for aggressive phenotypes. Distinguishing non-muscle invasive subtypes benefits from Keratin 17. Neu5Gc-modified UMOD glycoproteins pose potential in BC diagnosis, while fibronectin, laminin-5, collagen type IV, and lamprey immunity protein in early detection of BC.


Assuntos
Glicômica , Neoplasias da Bexiga Urinária , Humanos , Proteômica , Neoplasias da Bexiga Urinária/diagnóstico , Biomarcadores , Fenótipo , Proteínas Nucleares , Biomarcadores Tumorais
14.
Front Biosci (Landmark Ed) ; 29(1): 32, 2024 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-38287814

RESUMO

BACKGROUND: Aberrant glycosylation is a hallmark of cancer and thereby has an excellent potential for the discovery of novel biomarkers. Impairments in the glycan composition of lipoproteins impact their functional properties and can be associated with various diseases, including cancer. This research is still in its infancy; however, it can lead to the development of new diagnostic and disease stratification approaches as well as therapeutic strategies. Therefore, we aimed to evaluate anomalies in O-glycosylation of apolipoprotein C-III (apoC-III) in colorectal carcinoma (CRC) patients' sera, in comparison with sera from healthy individuals, and assess the disparities of O-glycoforms on apoC-III in CRC. METHODS: The choice of patients (n = 42) was based on the same tumor type (adenocarcinoma) and tumor size (T3), without or with inconsiderable lymph node infiltration. Patients with comorbidities were excluded from the study. The control healthy individuals (n = 40) were age- and sex-matched with patients. We used an approach based on the MALDI-TOF MS in linear positive ion mode, allowing simple analysis of O-glycosylation on intact apoC-III molecules in the serum samples directly, without the need for specific protein isolation. This approach enables relatively simple and high-throughput analysis. RESULTS: In CRC patients' sera samples, we observed significantly elevated apoC-III sialylation. Fully sialylated (disialylated) O-glycans had 1.26 times higher relative abundance in CRC samples compared to controls with a p-value of Mann-Whitney U test of 0.0021. CONCLUSIONS: We found altered O-glycosylation of apoC-III in the serum of CRC patients. However, it can be non-specific as it may be associated with another process such as ongoing inflammation. Therefore, to establish it as a potential novel non-invasive biomarker for CRC in suspected patients, further studies interrogating the changes in apoC-III O-glycosylation and the robustness of this biomarker need to be performed and evaluated.


Assuntos
Neoplasias Colorretais , Polissacarídeos , Humanos , Apolipoproteína C-III , Glicosilação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Biomarcadores , Neoplasias Colorretais/diagnóstico
15.
Macromol Rapid Commun ; 34(8): 635-9, 2013 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-23401120

RESUMO

A novel cationic polymer poly(N,N-dimethyl-N-[3-(methacroylamino) propyl]-N-[2-[(2-nitrophenyl)methoxy]-2-oxo-ethyl]ammonium chloride) is synthesized by free-radical polymerization of N-[3-(dimethylamino)propyl] methacrylamide and subsequent quaternization with o-nitrobenzyl 2-chloroacetate. The photolabile o-nitrobenzyl carboxymethyl pendant moiety is transformed to the zwitterionic carboxybetaine form upon the irradiation at 365 nm. This feature is used to condense and, upon the light irradiation, to release double-strand DNA tested by gel electrophoresis and surface plasmon resonance experiments as well as to switch the antibacterial activity to non-toxic character demonstrated for Escherichia coli bacterial cells in solution and at the surface using the self-assembled monolayers.


Assuntos
DNA/metabolismo , Escherichia coli/metabolismo , Luz , Polímeros/química , Acrilamidas/química , Cátions/química , DNA/química , Escherichia coli/efeitos dos fármacos , Radicais Livres/química , Fotólise , Polímeros/síntese química , Polímeros/farmacologia , Compostos de Amônio Quaternário/química , Ressonância de Plasmônio de Superfície
16.
Cells ; 12(3)2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36766693

RESUMO

As we already reported, fibrinogen fucosylation emerged as a prognostic marker of peritoneal membrane function in end-stage renal disease (ESRD) patients on peritoneal dialysis. After a follow-up period of 18 months, we estimated the ability of employed lectins, as well as other biochemical parameters, to serve as mortality predictors in these patients. Following a univariate Cox regression analysis, ferritin, urea clearance, residual diuresis, hyperglycemia, and an increase in the signal intensity obtained with Galanthus nivalis lectin (GNL) emerged as potential mortality predictors, but additional multivariate Cox regression analysis pointed only to glucose concentration and GNL as mortality predictors. Higher signal intensity obtained with GNL in patients that died suggested the importance of paucimannosidic/highly mannosidic N-glycan structures on fibrinogen as factors that are related to unwanted cardiovascular events and all-cause mortality and can possibly be seen as a prediction tool. Altered glycan structures composed of mannose residues are expected to affect the reactivity of mannosylated glycoproteins with mannose-binding lectin and possibly the entire cascade of events linked to this lectin. Since patients with ESRD are prone to cardiovascular complications and the formation of atherosclerotic plaques, one can hypothesize that fibrinogen with increasingly exposed mannose residues may contribute to the unwanted events.


Assuntos
Hemostáticos , Falência Renal Crônica , Diálise Peritoneal , Humanos , Fibrinogênio , Manose , Lectinas , Polissacarídeos/química
17.
MethodsX ; 11: 102402, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37846355

RESUMO

In this manuscript, we present a comprehensive fabrication protocol for high-performance graphene oxide (GO) sensor concepts. It is suitable for a variety of biosensing applications and contains the essential process steps, starting with vapor phase evaporation for siloxane monolayers, followed by spin-coating of GO as a nanometer-thin transducer with exceptional homogeneity and micromechanical surface methods which enable seamless transformation of GO transducers to be desired micro and nano dimensions. In addition to linking basic research and innovative sensor concepts with an outlook for commercial applications of point-of-care systems for early-stage diagnostics, the authors consider it necessary to take a closer look at the manufacturing processes to create more transparency and clarity, to manufacture such specific sensor concepts systematically. The detailed manufacturing approaches are intended to motivate practitioner to explore and improve this GO-based key technology. This process development is illustrated below using the manufacturing methods for three types of sensors, namely sensors based on i) surface plasmon resonance spectroscopy (SPR), ii) impedance spectroscopy and iii) bio-field effect transistors (ISFETs). The obtained results in this work prove successful GO sensor productions by achieving:•Uniform and stable immobilization of GO thin films,•High yield of sensor units on a wafer scale, here up to 96 %,•Promising integration potential for various biomedical sensor concepts to early-stage diagnostic.

18.
Front Biosci (Landmark Ed) ; 28(2): 39, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36866557

RESUMO

BACKGROUND: Alpha-mannosidosis is a rare lysosomal storage disorder, caused by decreased activity of α-D-mannosidase. This enzyme is involved in the hydrolysis of mannosidic linkages in N-linked oligosaccharides. Due to the mannosidase defect, undigested mannose-rich oligosaccharides (Man2GlcNAc - Man9GlcNAc) accumulating in cells are excreted in large quantities in urine. METHODS: In this work, we determined the levels of urinary mannose-rich oligosaccharides in a patient subjected to novel enzyme replacement therapy. Urinary oligosaccharides were extracted using solid phase extraction (SPE), labeled by fluorescent tag 2-aminobenzamide, and quantified by high-performance liquid chromatography (HPLC) with fluorescence detector (FLD). The identity of peaks was determined by matrix-assisted laser desorption/ionization time-of-flight/time-of-flight (MALDI-TOF/TOF) mass spectrometry. In addition, the levels of urinary mannose-rich oligosaccharides were also quantified by 1H nuclear magnetic resonance (NMR) spectroscopy. The data were analyzed using one-tailed paired t-test and Pearson's correlation tests. RESULTS: Compared to levels before the administration of therapy, an approximately two-folds decrease in total mannose-rich oligosaccharides after one month of treatment was observed by NMR and HPLC. After four months, an approximately ten-folds significant decrease in total urinary mannose-rich oligosaccharides was detected, suggesting therapy effectiveness. A significant decrease in the levels of oligosaccharides with 7-9 mannose units was detected by HPLC. CONCLUSIONS: The application of both HPLC-FLD and NMR in quantification of oligosaccharide biomarkers is a suitable approach for monitoring of therapy efficacy in alpha-mannosidosis patients.


Assuntos
alfa-Manosidose , Humanos , Cromatografia Líquida de Alta Pressão , alfa-Manosidose/tratamento farmacológico , Manose , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética
19.
Nutrients ; 15(9)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37432214

RESUMO

In previous publications, we pointed out the importance of mannosylation of fibrinogen for the development of cardiovascular complications and fucosylation as a predictor of peritoneal membrane dysfunction in patients on peritoneal dialysis (PD). After a follow-up period of 30 months from the onset of the COVID-19 pandemic, we evaluated the significance of 1,25-dihydroxyvitamin D3 (calcitriol) therapy, primary disease, biochemical and hematologic analyzes, and previously performed glycan analysis by lectin-based microarray as predictors of mortality in this patient group. After univariate Cox regression analysis, diabetes mellitus (DM) and calcitriol therapy were found to be potential predictors of mortality. Additional multivariate Cox regression analysis confirmed that only DM was a predictor of mortality. Nevertheless, the use of calcitriol in therapy significantly reduced mortality in this patient group, as shown by the Kaplan-Meier survival curve. The presence of DM as a concomitant disease proved to be a strong predictor of fatal outcome in PD patients infected with SARS-CoV-2. This is the first study to indicate the importance and beneficial effect of calcitriol therapy on survival in PD patients with COVID-19 infection. In addition, this study points to the possibility that adverse thrombogenic events observed in PD patients during the pandemic may be caused by aberrant fibrinogen glycosylation.


Assuntos
COVID-19 , Hemostáticos , Diálise Peritoneal , Humanos , Calcitriol , Pandemias , SARS-CoV-2 , Diálise Peritoneal/efeitos adversos , Fibrinogênio
20.
Curr Med Chem ; 29(37): 5795-5814, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35619313

RESUMO

BACKGROUND: Biomarkers are characteristic molecules that can serve as indicators of biological process status or condition; here, they are being studied with special relevance to Parkinson's Disease (PD). This disease is a chronic neurodegenerative disorder very difficult to study given the site of pathology and due to a clinical phenotype that fluctuates over time. Currently, there is no definitive diagnostic test for Parkinson's Disease; thus, clinicians hope that the detection of crucial biomarkers will help in the symptomatic and presymptomatic diagnostics and provide surrogate endpoints to demonstrate the clinical efficacy of new treatments. METHODS: Electrochemical aptasensors are excellent analytical tools that are used in the detection of PD biomarkers, as they are portable, easy to use, and perform real-time analysis. RESULTS: In this review, we discuss the most important clinical biomarkers for PD, highlighting their physiological role and function in the disease. Herein, we review, for the first time, innovative aptasensors for the detection of current potential PD biomarkers based on electrochemical techniques and discuss future alternatives, including ideal analytical platforms for point-of-care diagnostics. CONCLUSION: These new tools will be critical not only in the discovery of sensitive, specific, and reliable biomarkers of preclinical PD, but also in the development of tests that can assist in the early detection and differential diagnosis of parkinsonian disorders and in monitoring disease progression. Various methods for fixing aptamers onto the sensor surfaces, enabling quantitative and specific PD biomarker detection present in synthetic and clinical samples, will also be discussed.


Assuntos
Doença de Parkinson , Biomarcadores/análise , Progressão da Doença , Técnicas Eletroquímicas , Humanos , Doença de Parkinson/diagnóstico , Resultado do Tratamento
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