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1.
Curr Issues Mol Biol ; 45(4): 3603-3627, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37185759

RESUMO

Nearly 90% of cervical cancers are linked to human papillomavirus (HPV). Uncovering the protein signatures in each histological phase of cervical oncogenesis provides a path to biomarker discovery. The proteomes extracted from formalin-fixed paraffin-embedded tissues of the normal cervix, HPV16/18-associated squamous intraepithelial lesion (SIL), and squamous cell carcinoma (SCC) were compared using liquid chromatography-mass spectrometry (LC-MS). A total of 3597 proteins were identified, with 589, 550, and 1570 proteins unique to the normal cervix, SIL, and SCC groups, respectively, while 332 proteins overlapped between the three groups. In the transition from normal cervix to SIL, all 39 differentially expressed proteins were downregulated, while all 51 proteins discovered were upregulated in SIL to SCC. The binding process was the top molecular function, while chromatin silencing in the SIL vs. normal group, and nucleosome assembly in SCC vs. SIL groups was the top biological process. The PI3 kinase pathway appears crucial in initiating neoplastic transformation, while viral carcinogenesis and necroptosis are important for cell proliferation, migration, and metastasis in cervical cancer development. Annexin A2 and cornulin were selected for validation based on LC-MS results. The former was downregulated in the SIL vs. normal cervix and upregulated in the progression from SIL to SCC. In contrast, cornulin exhibited the highest expression in the normal cervix and lowest in SCC. Although other proteins, such as histones, collagen, and vimentin, were differentially expressed, their ubiquitous expression in most cells precluded further analysis. Immunohistochemical analysis of tissue microarrays found no significant difference in Annexin A2 expression between the groups. Conversely, cornulin exhibited the strongest expression in the normal cervix and lowest in SCC, supporting its role as a tumor suppressor and potential biomarker for disease progression.

2.
Yeast ; 40(5-6): 171-181, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37070695

RESUMO

Beer refermentation in bottles is an industrial process utilized by breweries where yeast and fermentable extract are added to green beer. The beer is refermented for a minimum of 2 weeks before distribution, with the physiological state of the yeast a critical factor for successful refermentation. Ideally, fresh yeast that is propagated from a dedicated propagation plant should be used for refermentation in bottles. Here, we explored the applicability of the fluorescent and redox-sensitive dye, resazurin, to assess cellular metabolism in yeast and its ability to differentiate between growth stages. We applied this assay, with other markers of yeast physiology, to evaluate yeast quality during a full-scale industrial propagation. Resazurin allowed the discrimination between the different growth phases in yeast and afforded a more in-depth understanding of yeast metabolism during propagation. This assay can be used to optimize the yeast propagation process and cropping time to improve beer quality.


Assuntos
Cerveja , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Fermentação , Cerveja/análise , Oxirredução
3.
J Chromatogr A ; 1691: 463813, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36709548

RESUMO

Over the past two decades significant technical advancement in the field of western blotting has been made possible through the utilization of microfluidic technologies. In this review we provide a critical overview of these advancements, highlighting the advantages and disadvantages of each approach. Particular attention is paid to the development of now commercially available systems, including those for single cell analysis. This review also discusses more recent developments, including algorithms for automation and/or improved quantitation, the utilization of different materials/chemistries, use of projection electrophoresis, and the development of triBlots. Finally, the review includes commentary on future advances in the field based on current developments, and the potential of these systems for use as point-of-care devices in healthcare.


Assuntos
Técnicas Analíticas Microfluídicas , Microfluídica , Sistemas Automatizados de Assistência Junto ao Leito , Western Blotting , Automação
4.
RSC Adv ; 12(16): 9773-9785, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35424961

RESUMO

Poly(styrene-co-divinylbenzene)-based monoliths were prepared from the polymerisation of water-in-monomer high internal phase emulsions, where the water-soluble monomers acrylamide (AAm) or poly(ethylene glycol) diacrylate (PEGDA) (M w 258) were also included in the 90 vol% internal phase. Both AAm and PEGDA were found to act as co-surfactants, resulting in the obtainment of monoliths with greater homogeneity in some cases. As a result these materials demonstrated significantly improved chromatographic performance for the separation of a standard mixture of proteins using reversed-phase liquid chromatography, in comparison to monoliths prepared with no internal phase monomer. In particular, the columns grafted with PEGDA were capable of separating a more complex mixture consisting of seven components. The inclusion of monomers in the internal phase also allowed for the functionalisation of the monolith's surface where the degree of polymerisation that occurred in the internal phase, which was governed by the monomer content in the internal phase and initiation location, determined whether polymeric chains or a hydrogel were grafted to the surface. A monolith grafted with AAm was also found to be capable of retaining polar analytes as a result of the increase in surface hydrophilicity.

5.
J Chromatogr A ; 1654: 462464, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34438302

RESUMO

The effect of adding ethoxylated sorbitan ester surfactants (Tweens®) to poly(ethylene glycol) diacrylate-based monolithic recipes was investigated. Five different Tweens® have been evaluated to investigate the exact role of non-ionic surfactants in poly(ethylene glycol) diacrylate-based monolith preparations. These monoliths were characterized by scanning electron microscopy, infrared spectroscopy, and nitrogen physisorption analysis. Different morphological features, and surface areas were observed when different types of Tween® were included in the recipe; Tween® 20 and 85 showed small globules, while Tween® 40, 60 and 80 exhibited larger globular structures with different sizes and degrees of coalescence. The different Tween®-based monoliths were investigated for the chromatographic separation of mixtures consisting of hydroxybenzoic acids and alkylbenzenes. These columns were mechanically stable, except for Tween® 80. The highest methylene selectivity and the best overall performance were achieved by Tween® 60. The efficiency was increased by increasing the concentration of the Tween® 60 and the amount of poly(ethylene glycol) diacrylate Mn 700 in the recipes up to 30 wt%, each. Further increases in either Tween® 60 or poly(ethylene glycol) diacrylate Mn 700 led to formation of non-permeable columns. The optimized column was successfully used for separation of mixtures of nonsteroidal anti-inflammatory and sulfa drugs, with a maximum efficiency of 60,000 plates/m.


Assuntos
Técnicas de Química Analítica , Cromatografia , Ésteres , Polissorbatos , Tensoativos , Anti-Inflamatórios não Esteroides/isolamento & purificação , Técnicas de Química Analítica/métodos , Técnicas de Química Analítica/normas , Cromatografia/instrumentação , Cromatografia/normas , Ésteres/química , Hidroxibenzoatos , Polissorbatos/química
6.
Anal Chem ; 93(5): 2802-2810, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33496173

RESUMO

The influence of the addition of various non-ionic surfactants to poly(ethylene glycol) diacrylate-based monolith formulations was studied. Eight non-ionic surfactants having different chemistries were chosen for this study. These surfactants were Brij L4, Span 80, IGEPAL CO-520, Tergitol 15S9, 2,4,7,9-tetramethyl-5-decyne-4,7-diol ethoxylate, Tween 40, Triton X-405, and Tetronic 701. The chemical structures of these surfactants have a variety of functional groups and cover a wide range of molecular weights (360-3600 g/mol), viscosities (60-1500 cP), and hydrophilic-lipophilic balances (1.0-17.6). The formed polymers were characterized by scanning electron microscopy, surface area measurement by the Brunauer-Emmet-Teller method, elemental analysis, and Fourier transform infrared. Four formulations, involving the use of surfactants, resulted in permeable materials when prepared in 150 µm ID silica capillaries. The chromatographic performance of the resulting columns in reversed-phase mode was evaluated and compared using a mixture of alkyl benzenes as test analytes. The highest efficiency and methylene selectivity were observed when Tween 40 was included in the formulation, using decane/decanol/dodecanol as coporogens. This porogenic mixture was successfully used for preparation of monolithic columns from a selection of methacrylate- and styrene-based monomers, including butylmethacrylate, hydroxyethymethacrylate, laurylmethacrylate, glycidyl methacrylate, bisphenol diacrylate, benzylmethacrylate, and N,N-dimethylacrylamide, as well as for divinylbenzene. These results show the applicability of this porogenic mixture for a variety of monolithic formulations, providing an approach for developing a universal porogen system.

7.
Anal Sci Adv ; 2(3-4): 225-237, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38716449

RESUMO

The applicability of mass spectrometry imaging (MSI) has exponentially increased with the improvement of sample preparation, instrumentation (spatial resolution) and data analysis. The number of MSI publications listed in PubMed continues to grow with 378 published articles in 2020-2021. Initially, MSI was just sensitive enough to identify molecular features correlating with distinct tissue regions, similar to the resolution achieved by visual inspection after standard immunohistochemical staining. Although the spatial resolution was limited compared with other imaging modalities, the molecular intensity mapping added a new exciting capability. Over the past decade, significant improvements in every step of the workflow and most importantly in instrumentation were made, which now enables the molecular analysis at a cellular and even subcellular level. Here, we summarize the latest developments in MSI, with a focus on the latest approaches for tissue-based imaging described in 2020.

8.
RSC Adv ; 9(13): 7301-7313, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35519965

RESUMO

Poly(styrene-co-divinylbenzene) monoliths were prepared from the polymerisation of water-in-monomer high internal phase emulsions consisting of a 90 vol% internal phase and stabilised by the non-ionic surfactant Span 80®. The materials were prepared in capillary housings of various internal diameters ranging from 150 µm to 540 µm by simply passing the emulsion through the capillaries. When low shear (300 rpm) was used for emulsification, the droplet and resulting void size distributions were observed to shift towards lower values when the emulsions were forced through capillaries of internal diameter less than 540 µm and all columns exhibited significant radial heterogeneity. When high shear was employed (14 000 rpm) the resulting emulsions preserved their structure when forced through these capillaries and possessed narrower void size distributions with no obvious radial heterogeneity observed upon curing. This resulted in significantly improved chromatographic performance for the separation of a standard mixture of proteins when compared to the materials prepared under low shear.

9.
Anal Chem ; 90(20): 12081-12089, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30222326

RESUMO

Multimaterial 3D printing facilitates the rapid production of complex devices with integrated materials of varying properties and functionality. Herein, multimaterial fused deposition modeling (MM-FDM) 3D printing was applied to the fabrication of low-cost passive sampler devices with integrated porous membranes. Using MM-FDM 3D printing, the device body was produced using black polylactic acid, with Poro-Lay Lay-Felt filament used for the printing of the integrated porous membranes (rubber-elastomeric polymer, porous after removal of a water-soluble poly(vinyl alcohol) component). The resulting device consisted of two interlocking circular frames, each containing the integrated membrane, which could be efficiently sealed together without the need for additional O-rings, and prevented loss of enclosed microparticulate sorbent. Scanning electron microscopy (SEM) analysis of the purified composite filament confirmed the porous properties of the material, an average pore size of ∼30 nm. The printed passive samplers with various membrane thicknesses, including 0.5, 1.0, and 1.5 mm, were evaluated for their ability to facilitate the extraction of atrazine as the model solute onto the internal sorbent, under standard conditions. Gas chromatography-mass spectrometry was used to determine the uptake of atrazine by the device from standard water samples and also to evaluate any chemical leaching from the printed materials. The sampler with 0.5 mm thick membrane showed the best performance with 87% depletion and a sampling rate of 0.19 Ld-1 ( n = 3, % RSD = 0.59). The results obtained using these printed sampling devices with integrated membranes were in close agreement to devices fitted with a standard poly(ether sulfone) membrane.

10.
J Sep Sci ; 36(17): 2782-92, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23813673

RESUMO

Polymer monoliths were prepared in 150 µm id capillaries by thermally initiated polymerization of PEG diacrylate for rapid hydrophobic interaction chromatography of immunoglobulin G (IgG) subclasses and related variants. Using only one monomer in the polymerization mixture allowed ease of optimization and synthesis of the monolith. The performance of the monolith was demonstrated by baseline resolution of IgG subclasses and variants, including mixtures of the κ variants of IgG1, IgG2, and IgG3 as well as the κ and λ variants associated with IgG1 and IgG2. The effect of eluent concentration and pH on the separation efficiency of studied proteins was also explored, allowing almost baseline resolution to be achieved for mixtures of the κ variants of IgG1, IgG2, IgG3, and IgG4 but also for the κ and λ variants of IgG1 and IgG2. The results showed significant improvement in the separations in terms of the tradeoff between analysis time and resolution, while maintaining a simple methodology, in comparison to previous reports. The synthesized monolith was also used for the separation of isoforms of a therapeutic monoclonal antibody.


Assuntos
Cromatografia Líquida/instrumentação , Imunoglobulina G/isolamento & purificação , Polietilenoglicóis/química , Anticorpos Monoclonais/imunologia , Cromatografia Líquida/métodos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Imunoglobulina G/classificação , Imunoglobulina G/imunologia , Microscopia Eletrônica de Varredura
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