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1.
Gels ; 8(4)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35448103

RESUMO

Fenton reactions with metal complexes of substituted porphyrins and hydrogen peroxide are useful tools for the mineralization of environmentally dangerous substances. In the homogeneous phase, autooxidation of the prophyrin ring may also occur. Covalent binding of porphyrins to a solid support may increase the lifetime of the catalysts and might change its activity. In this study, highly water-insoluble copper and iron complexes of 5,10,15,20-tetrakis(4-aminophenyl)porphyrin were synthesized and bonded covalently to a very hydrophilic silica aerogel matrix prepared by co-gelation of the propyl triethoxysilyl-functionalized porphyrin complex precursors with tetramethoxysilane, followed by a supercritical carbon dioxide drying. In contrast to the insoluble nature of the porphyrin complexes, the as-prepared aerogel catalysts were highly compatible with the aqueous phase. Their catalytic activities were tested in the mineralization reaction of phenol, 3-chlorophenol, and 2,4-dichlorophenol with hydrogen peroxide. The results show that both aerogels catalyzed the oxidation of phenol and chlorophenols to harmless short-chained carboxylic acids under neutral conditions. In batch experiments, and also in a miniature continuous-flow tubular reactor, the aerogel catalysts gradually reduced their activity, due to the slow oxidation of the porphyrin ring. However, the rate and extent of the degradation was moderate and did not exclude the possibility that the as-prepared catalysts, as well as their more stable derivatives, might find practical applications in environment protection.

2.
Biomolecules ; 12(1)2021 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-35053167

RESUMO

Semi-quantitative scoring is a method that is widely used to estimate the quantity of proteins on chromogen-labelled immunohistochemical (IHC) tissue sections. However, it suffers from several disadvantages, including its lack of objectivity and the fact that it is a time-consuming process. Our aim was to test a recently established artificial intelligence (AI)-aided digital image analysis platform, Pathronus, and to compare it to conventional scoring by five observers on chromogenic IHC-stained slides belonging to three experimental groups. Because Pathronus operates on grayscale 0-255 values, we transformed the data to a seven-point scale for use by pathologists and scientists. The accuracy of these methods was evaluated by comparing statistical significance among groups with quantitative fluorescent IHC reference data on subsequent tissue sections. The pairwise inter-rater reliability of the scoring and converted Pathronus data varied from poor to moderate with Cohen's kappa, and overall agreement was poor within every experimental group using Fleiss' kappa. Only the original and converted that were obtained from Pathronus original were able to reproduce the statistical significance among the groups that were determined by the reference method. In this study, we present an AI-aided software that can identify cells of interest, differentiate among organelles, protein specific chromogenic labelling, and nuclear counterstaining after an initial training period, providing a feasible and more accurate alternative to semi-quantitative scoring.


Assuntos
Inteligência Artificial , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Software , Humanos
3.
Electrophoresis ; 42(3): 200-205, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33128395

RESUMO

Although knowledge on glycan biosynthesis and processing is continuously maturing, there are still a limited number of studies that examine biological functions of N-glycan structures in plants, which remain virtually unknown. Here, the statistical correlation between nutrient (nitrogen) deficiency symptoms of crops and changes in 8-aminopyrene-1,3,6-trisulfonic acid (APTS)-labeled complex type free oligosaccharides is reported. While deficiency symptoms are predicted by multispectral images and Kjeldahl digestion, APTS-labeled complex type free oligosaccharides are identified by their glucose unit (GU) values in tomato xylem sap, using capillary electrophoresis with laser induced fluorescence detection (CE-LIF). Given the limited number of structures obtained from plants, archived in the literature, in the future, it is intended to create an open access database of promising indicators, namely, glycan structures that are presumably responsible for the nutrient deficiency caused stress in plants (http://glycoplants.org).


Assuntos
Eletroforese Capilar/métodos , Oligossacarídeos , Polissacarídeos , Solanum lycopersicum , Xilema/química , Glucose/análise , Glucose/química , Glicosilação , Solanum lycopersicum/química , Solanum lycopersicum/metabolismo , Solanum lycopersicum/fisiologia , Oligossacarídeos/análise , Oligossacarídeos/química , Polissacarídeos/análise , Polissacarídeos/química
4.
Curr Mol Med ; 20(10): 765-772, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32321401

RESUMO

BACKGROUND: Immunoglobulin G and A, transferrin, haptoglobin and alpha-1- antitrypsin represent approximately 85% of the human serum glycoproteome and their N-glycosylation analysis may lead to the discovery of important molecular disease markers. However, due to the labile nature of the sialic acid residues, the desialylated subset of the serum N-glycoproteome has been traditionally utilized for diagnostic applications. OBJECTIVE: Creating a five-protein model to deconstruct the overall N-glycosylation fingerprints in inflammatory and malignant lung diseases. METHODS: The N-glycan pool of human serum and the five high abundant serum glycoproteins were analyzed. Simultaneous endoglycosidase/sialidase digestion was followed by fluorophore labeling and separation by CE-LIF to establish the model. Pooled serum samples from patients with COPD, lung cancer (LC) and their comorbidity were all analyzed. RESULTS: Nine significant (>1%) asialo-N-glycan structures were identified both in human serum and the standard protein mixture. The core-fucosylated-agalacto-biantennary glycan differentiated COPD and LC and both from the control and the comorbidity groups. Decrease in the core-fucosylated-agalacto-biantennary-bisecting, monogalacto and bigalacto structures differentiated all disease groups from the control. The significant increase of the fucosylated-galactosylated-triantennary structure was highly specific for LC, to a medium extent for COPD and a lesser extent for comorbidity. Also, some increase in the afucosylated-galactosylated-biantennary structure in all three disease types and afucosylated-galactosylated-triantennary structures in COPD and LC were observed in comparison to the control group. CONCLUSION: Our results suggested that changes in the desialylated human serum Nglycome hold glycoprotein specific molecular diagnostic potential for malignant and inflammatory lung diseases, which can be modeled with the five-protein mixture.


Assuntos
Biomarcadores/sangue , Neoplasias Pulmonares/diagnóstico , Modelos Biológicos , Polissacarídeos/sangue , Ácidos Siálicos/química , Idoso , Estudos de Casos e Controles , Feminino , Glicômica , Glicosilação , Humanos , Neoplasias Pulmonares/sangue , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica
5.
Brain Sci ; 10(2)2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-32012723

RESUMO

: Alzheimer's disease (AD) is the most common neurodegenerative dementia. Mapping the pathomechanism and providing novel therapeutic options have paramount significance. Recent studies have proposed the role of LMTK2 in AD. However, its expression pattern and association with the pathognomonic neurofibrillary tangles (NFTs) in different brain regions and neuropathological stages of AD is not clear. We performed chromogenic (CHR) LMTK2 and fluorescent phospho-tau/LMTK2 double-labelling (FDL) immunohistochemistry (IHC) on 10-10 postmortem middle frontal gyrus (MFG) and anterior hippocampus (aHPC) samples with early and late neuropathological Braak tau stages of AD. MFG in early stage was our 'endogenous control' region as it is not affected by NFTs. Semiquantitative CHR-IHC intensity scoring revealed significantly higher (p < 0.001) LMTK2 values in this group compared to NFT-affected regions. FDL-IHC demonstrated LMTK2 predominance in the endogenous control region, while phospho-tau overburden and decreased LMTK2 immunolabelling were detected in NFT-affected groups (aHPC in early and both regions in late stage). Spearman's correlation coefficient showed strong negative correlation between phospho-tau/LMTK2 signals within each group. According to our results, LMTK2 expression is inversely proportionate to the extent of NFT pathology, and decreased LMTK2 level is not a general feature in AD brain, rather it is characteristic of the NFT-affected regions.

6.
Sci Rep ; 9(1): 17222, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31748522

RESUMO

Alzheimer's disease (AD) and neocortical Lewy body disease (LBD) are the most common neurodegenerative dementias, with no available curative treatment. Elucidating pathomechanism and identifying novel therapeutic targets are of paramount importance. Lemur tyrosine kinase 2 (LMTK2) is involved in several physiological and pathological cellular processes. Herewith a neuropathological characterization is presented in AD and neocortical LBD samples using chromogenic and fluorescent LMTK2 immunohistochemistry on post-mortem brain tissues and compared them to age-matched controls (CNTs). LMTK2 immunopositivity was limited to the neuronal cytoplasm. Neurons, including tau-positive tangle-bearing ones, showed decreased chromogenic and immunofluorescent labelling in AD in every cortical layer compared to CNT and neocortical LBD. Digital image analysis was performed to measure the average immunopositivity of groups. Mean grey values were calculated for each group after measuring the grey scale LMTK2 signal intensity of each individual neuron. There was significant difference between the mean grey values of CNT vs. AD and neocortical LBD vs. AD. The moderate decrease in neocortical LBD suggests the effect of coexisting AD pathology. We provide neuropathological evidence on decreased neuronal LMTK2 immunolabelling in AD, with implications for pathogenesis.


Assuntos
Doença de Alzheimer/patologia , Biomarcadores/metabolismo , Doença por Corpos de Lewy/patologia , Proteínas de Membrana/metabolismo , Neocórtex/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Doença de Alzheimer/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Doença por Corpos de Lewy/metabolismo , Masculino , Pessoa de Meia-Idade , Neocórtex/metabolismo , Prognóstico
7.
Anal Chem ; 91(12): 7738-7743, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31136147

RESUMO

Laser-induced fluorescence detection (LIF) is a powerful tool for the quantitative analysis of fluorescent molecules, widely used in glycan analysis with fluorophore labeled carbohydrates where each species has a common response factor. Electrospray ionization mass spectrometry (ESI-MS), on the other hand, while revealing important structural information about individual analytes, generally can have different response factors for different species. For simpler and improved quantitation with ESI-MS, laser-induced fluorescent images were collected at the Taylor cone of the electrospray interface, enabling simultaneous and robust optical (quantitative) and MS (qualitative) detection of fluorophore labeled sugars. The performance of this universally applicable, interface design independent imaging laser-induced fluorescent (iLIF) system was demonstrated using capillary electrophoresis (CE)-ESI-MS in the analysis of aminopyrene-trisulfonate labeled linear maltooligosaccharides and branched glycans from human immunoglobulin. The limit of detection (LOD) of the iLIF system was in this case 40 attomole. The intra- and interday quantitative (peak area) reproducibilities of the system (RSD) were 4.15% and 6.79%, respectively.

8.
Electrophoresis ; 39(22): 2884-2889, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30112845

RESUMO

The search for biotic compounds beyond planet Earth is among the highest priorities in space discovery. We sought to detect organic molecules in various earth soil samples collected from environments with extreme climatic conditions comparable to extraterrestrial environments using HPLC, spectrophotometry (UV, IR), GC/MS and vertical gel electrophoresis analyses systems. The applied methods in the study were compared using a self-developed software tool that was designed to evaluate the viability of instrument selection for organics detection in any given exploratory mission. The tool was created to aid further development and refinements of rapidly improving technological solutions such as MCE and MS instruments. Such comparison can be done quickly and easily, acting as a decision support tool when choosing between analytical methods during any planning phase of future exploration missions led by space agencies (i.e., NASA).


Assuntos
Algoritmos , Técnicas de Química Analítica/métodos , Exobiologia/métodos , Meio Ambiente Extraterreno/química , Compostos Orgânicos/análise , Técnicas de Apoio para a Decisão , Voo Espacial
9.
Electrophoresis ; 39(22): 2851-2853, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30101988

RESUMO

By reading the commentary of Bevelacqua and Mortazavi regarding our recently published paper titled as "The effect of simulated space radiation on the N-glycosylation of human immunoglobulin G1"[1], we are afraid that some of the important messaging aspects of our paper might not have been articulated adequately to be fully understandable for a wider audience, i.e., not separation scientists. First, we should clarify that complete space radiation description was not the goal of this paper. In this short communication we only intended to show the effect of simulated space radiation on the conserved N-glycosylation of IgG1 molecules with the goal to understand if they could be utilized as disease biomarkers during longer space missions, similar to that as they are currently used here on Earth, e.g. for autoimmune disease or aging markers. Therefore, no discussion was given about any biological effects either as our study only investigated the qualitative effects of proton irradiation on the N-linked carbohydrate decomposition of IgG type 1 molecules with the intent of suggesting them to be used as biomarkers during deep space travel. Radioadaptation was never an issue in our study for the reasons mentioned above.


Assuntos
Carboidratos , Imunoglobulina G , Biomarcadores , Eletroforese , Glicosilação , Humanos
10.
Electrophoresis ; 39(22): 2872-2876, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29775210

RESUMO

On a roundtrip to Mars, astronauts are expectedly exposed to an approximate amount of radiation that exceeds the lifetime limits on Earth. This elevated radiation dose is mainly due to Galactic Cosmic Rays and Solar Particle Events. Specific patterns of the N-glycosylation of human Igs have already been associated with various ailments such as autoimmune diseases, malignant transformation, chronic inflammation, and ageing. The focus of our work was to investigate the effect of low-energy proton irradiation on the IgG N-glycosylation profile with the goal if disease associated changes could be detected during space travel and not altered by space radiation. Two ionization sources were used during the experiments, a Van de Graaff generator for the irradiation of solidified hIgG samples in vacuum, and a Tandetron accelerator to irradiate hIgG samples in aqueous solution form. Structural carbohydrate analysis was accomplished by CE with laser induced fluorescent detection to determine the effects of simulated space radiation on N-glycosylation of hIgG1 samples. Our results revealed that even several thousand times higher radiation doses that of astronauts can suffer during long duration missions beyond the shielding environment of Low Earth Orbit, no changes were observed in hIgG1 N-glycosylation. Consequently, changes in N-linked carbohydrate profile of IgG1 can be used as molecular diagnostic tools in space.


Assuntos
Radiação Cósmica/efeitos adversos , Glicosilação/efeitos da radiação , Imunoglobulina G , Voo Espacial , Astronautas , Eletroforese Capilar , Humanos , Imunoglobulina G/análise , Imunoglobulina G/química , Imunoglobulina G/efeitos da radiação , Modelos Teóricos
11.
Anal Chem ; 89(20): 10673-10678, 2017 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-28949126

RESUMO

We present the application of a smartphone anatomy based technology in the field of liquid phase bioseparations, particularly in capillary electrophoresis. A simple capillary electrophoresis system was built with LED induced fluorescence detection and a credit card sized minicomputer to prove the concept of real time fluorescent imaging (zone adjustable time-lapse fluorescence image processor) and separation controller. The system was evaluated by analyzing under- and overloaded aminopyrenetrisulfonate (APTS)-labeled oligosaccharide samples. The open source software based image processing tool allowed undistorted signal modulation (reprocessing) if the signal was inappropriate for the actual detection system settings (too low or too high). The novel smart detection tool for fluorescently labeled biomolecules greatly expands dynamic range and enables retrospective correction for injections with unsuitable signal levels without the necessity to repeat the analysis.


Assuntos
Corantes Fluorescentes/química , Processamento de Imagem Assistida por Computador/métodos , Oligossacarídeos/análise , Smartphone , Espectrometria de Fluorescência , Algoritmos , Eletroforese Capilar , Processamento de Imagem Assistida por Computador/instrumentação , Luz , Limite de Detecção , Oligossacarídeos/química , Pirenos/química
12.
Electrophoresis ; 38(12): 1602-1608, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28334446

RESUMO

Capillary electrophoresis with laser-induced fluorescence (CE-LIF) detection was used to analyze endoglycosidase released and fluorophore-labeled N-glycans from formalin-fixed paraffin-embedded (FFPE) mouse tissue samples of lung, brain, heart, spleen, liver, kidney and intestine. The FFPE samples were first deparaffinized followed by solubilization and glycoprotein retrieval. PNGase F mediated release of the N-linked oligosaccharides was followed by labeling with aminopyrene trisulfonate. After CE-LIF glycoprofiling of the FFPE mouse tissues, the N-glycan pool of the lung specimen was subject to further investigation by exoglycosidase array based carbohydrate sequencing. Structural assignment of the oligosaccharides was accomplished by the help of the GUcal software and the associated database, based on the mobility shifts after treatments with the corresponding exoglycosidase reaction mixtures. Sixteen major N-linked carbohydrate structures were sequenced from the mouse lung FFPE tissue glycome and identified, as high mannose (3) neutral biantennary (3) sialylated monoantennary (1) and sialylated bianennary (9) oligosaccharides. Two of these latter ones also possessed alpha(1-3) linked galactose residues.


Assuntos
Eletroforese Capilar/métodos , Oligossacarídeos/química , Polissacarídeos/análise , Animais , Configuração de Carboidratos , Sequência de Carboidratos , Corantes Fluorescentes , Galactose/química , Glicoproteínas/química , Masculino , Manose/química , Camundongos SCID , Especificidade de Órgãos , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase/química , Polissacarídeos/química
13.
Acta Microbiol Immunol Hung ; 63(4): 387-403, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27936861

RESUMO

Morphological transitions of wild-type and oxidative stress-tolerant Candida albicans strains were followed in the RPMI-FBS culture medium at pH values and CO2 levels characteristic for the anatomical niches inhabited by this opportunistic human pathogen fungus, including the oral cavity as well as the intestinal and vaginal lumens. Selected cultures were also supplemented with hemin modeling bleedings. Germination as well as elongation and branching of hyphae were monitored in the cultures using time-lapse video microscopy. Unexpectedly, branching time, which is defined as the time taken until the first branch of hypha emerges for the first time after germination, correlated well with alterations in the environmental conditions meanwhile no such correlations were found for germination time (time lasted until the appearance of the germination tube). Based on these observations, hypotheses were set up to estimate the significance of branching time in the pathogenesis of both superficial and systemic candidiases.


Assuntos
Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Candidíase/microbiologia , Dióxido de Carbono/farmacologia , Hemina/farmacologia , Candida albicans/metabolismo , Meios de Cultura/química , Meios de Cultura/metabolismo , Humanos , Concentração de Íons de Hidrogênio
14.
J Pharm Biomed Anal ; 128: 367-370, 2016 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-27337190

RESUMO

There is a growing demand in the biopharmaceutical industry for large scale N-glycosylation analysis of biotherapeutics, especially monoclonal antibodies. To fulfill this high throughput analysis requirement with single column separation systems in most instances require finishing the entire analysis cycle including conditioning, injection and separation between sample injections. While in liquid chromatography it represents a challenge, multiple sample injection in capillary electrophoresis has already been demonstrated for one or two sample components by utilizing the concept of introducing sequential sample and buffer zones into the capillary tubing before the start of the separation process. It was also demonstrated in CE-MS mode, mostly to follow one sample component, identified by precise mass measurement. Here we introduce a novel multiple injection approach for rapid large scale capillary electrophoresis analysis of samples with biopharmaceutical interest supporting multicomponent optical detection with laser induced fluorescence. In Separation Window Dependent Multiple Injection (SWDMI) mode, the samples are consecutively injected in predefined time intervals, based on the window that covers the separation of all sample components. As a practical example, this newly developed SWDMI protocol was applied to rapid and large scale analysis of APTS labeled monoclonal antibody N-glycans using a short (20cm effective length) capillary column. Full analysis of 96 samples (injected from a well plate) was obtained in 4h, in contrast to consecutive individual separation cycle processing of the same samples that required 12h.


Assuntos
Anticorpos Monoclonais/química , Anticorpos Monoclonais/isolamento & purificação , Eletroforese Capilar/métodos , Polissacarídeos/análise , Polissacarídeos/isolamento & purificação
15.
F1000Res ; 5: 93, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29026521

RESUMO

Databases which store and manage long-term scientific information related to life science are used to store huge amounts of quantitative attributes. Introduction of a new entity attribute requires modification of the existing data tables and the programs that use these data tables. The solution is increasing the virtual data tables while the number of screens remains the same. The main objective of the present study was to introduce a logic called Joker Tao (JT) which provides universal data storage for cloud-based databases. It means all types of input data can be interpreted as an entity and attribute at the same time, in the same data table.

16.
Fungal Genet Biol ; 54: 1-14, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23485399

RESUMO

The cell wall integrity (CWI) signaling pathway is responsible for cell wall remodeling and reinforcement upon cell wall stress, which is proposed to be universal in fungal cultures. In Aspergillus nidulans, both the deletion of rlmA encoding the RlmA transcription factor in CWI signaling and low concentrations of the cell wall polymer intercalating agent Congo Red caused significant physiological changes. The gene deletion mutant ΔrlmA strain showed decreased CWI and oxidative stress resistances, which indicated the connection between the CWI pathway and the oxidative stress response system. The Congo Red stress resulted in alterations in the cell wall polymer composition in submerged cultures due to the induction of the biosynthesis of the alkali soluble fraction as well as the hydrolysis of cell wall biopolymers. Both RlmA and RlmA-independent factors induced by Congo Red stress regulated the expression of glucanase (ANID_00245, engA) and chitinase (chiB, chiA) genes, which promoted the autolysis of the cultures and also modulated the pellet sizes. CWI stress and rlmA deletion affected the expression of brlA encoding the early conidiophore development regulator transcription factor BrlA and, as a consequence, the formation of conidiophores was significantly changed in submerged cultures. Interestingly, the number of conidiospores increased in surface cultures of the ΔrlmA strain. The in silico analysis of genes putatively regulated by RlmA and the CWI transcription factors AnSwi4/AnSwi6 in the SBF complex revealed only a few jointly regulated genes, including ugmA and srrA coding for UgmA UDP-galactopyranose mutase and SrrA stress response regulator, respectively.


Assuntos
Aspergillus nidulans/crescimento & desenvolvimento , Aspergillus nidulans/genética , Parede Celular/genética , Reprodução Assexuada/genética , Estresse Fisiológico , Fatores de Transcrição/genética , Aspergillus nidulans/enzimologia , Autólise/genética , Parede Celular/metabolismo , Quitinases/genética , Quitinases/metabolismo , Vermelho Congo/toxicidade , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Deleção de Genes , Regulação Fúngica da Expressão Gênica , Reprodução Assexuada/fisiologia , Transdução de Sinais
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