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1.
Molecules ; 28(3)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36770886

RESUMO

In recent years, lycopene has been highlighted due to its antioxidant and anti-inflammatory properties, associated with a beneficial effect on human health. The aim of this study was to advance the studies of antioxidant and anti-inflammatory mechanisms on human keratinocytes cells (HaCaT) of a self-emulsifying drug delivery system (SEDDS) loaded with lycopene purified from red guava (nanoLPG). The characteristics of nanoLPG were a hydrodynamic diameter of 205 nm, a polydispersity index of 0.21 and a zeta potential of -20.57, providing physical stability for the nanosystem. NanoLPG demonstrated antioxidant capacity, as shown using the ORAC methodology, and prevented DNA degradation (DNA agarose). Proinflammatory activity was evaluated by quantifying the cytokines TNF-α, IL-6 and IL-8, with only IL-8 showing a significant increase (p < 0.0001). NanoLPG showed greater inhibition of the tyrosinase and elastase enzymes, involved in the skin aging process, compared to purified lycopene (LPG). In vitro treatment for 24 h with 5.0 µg/mL of nanoLPG did not affect the viability of HaCaT cells. The ultrastructure of HaCaT cells demonstrated the maintenance of morphology. This contrasts with endoplasmic reticulum stresses and autophagic vacuoles when treated with LPG after stimulation or not with LPS. Therefore, the use of lycopene in a nanoemulsion may be beneficial in strategies and products associated with skin health.


Assuntos
Antioxidantes , Interleucina-8 , Humanos , Licopeno , Antioxidantes/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Anti-Inflamatórios/farmacologia , DNA
2.
Anal Chem ; 83(18): 7035-43, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21809823

RESUMO

Biomedical sciences, and in particular biomarker research, demand efficient glycoprotein enrichment platforms. Herein magnetic nanoprobes (MNP), after being coated with three broad-spectrum lectins-concanavalin A (ConA), wheat germ agglutinin (WGA), and Maackia amurensis lectin (MA)-were utilized to selectively capture glycoproteins from human body fluids. Additionally, a new methodology, based on protection of the lectins with their target sugars prior to coupling with MNPs, was proposed to overcome the nonspecific nature of conjugation. This approach contributed to preserve lectin conformation, increasing by 40% and 90% the affinity of ConA and MA for glycoproteins in relation to synthesis with nonprotected lectins. Optimal operating conditions (temperature, time) and maximum binding capacities were further determined for each lectin by use of fetuin as a reference. The enhanced performance of lectin-based nanoplatforms was demonstrated by comparing MNP@ConA with conventional Sepharose@ConA. These experiments have shown that ConA immobilized on MNP exhibited 5 times higher affinity for fetuin and ovalbumin when compared with Sepharose@ConA with the same amount of immobilized lectin. MNP@Lectins were then applied to human serum, saliva, and urine and the recovered proteins were digested with trypsin and analyzed by nano-HPLC MALDI-TOF/TOF. This allowed the identification of 180 proteins, 90% of which were found to be glycosylated by use of bioinformatics tools, therefore revealing low levels of unspecific binding. Thus, MNP@lectins have proved to be a valuable tool for glycoproteomic studies, particularly when dealing with minute amounts of material.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Glicoproteínas/análise , Lectinas/metabolismo , Nanopartículas de Magnetita/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Concanavalina A/química , Concanavalina A/metabolismo , Fetuínas/metabolismo , Glicoproteínas/sangue , Glicoproteínas/urina , Glicosilação , Humanos , Proteínas Imobilizadas/química , Proteínas Imobilizadas/metabolismo , Lectinas/química , Ovalbumina/metabolismo , Ligação Proteica , Saliva/metabolismo , Sefarose/análogos & derivados , Sefarose/química , Sefarose/metabolismo , Tripsina/metabolismo , Aglutininas do Germe de Trigo/química , Aglutininas do Germe de Trigo/metabolismo
3.
Nanomaterials (Basel) ; 10(3)2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32106427

RESUMO

Silica nanoparticles (SiO2NPs) are one of the most used in commercial products and biomedical tools, however, their environmental effects have not been fully described. Although negative effects of SiO2NPs on the behavior of freshwater invertebrates have been reported, the knowledge is limited, especially the effect of nanopowders in terrestrial organisms. Accordingly, the aim of the present study is to understand the effects of SiO2NPs on the avoidance behavior of five soil species, whose niche may differ thus contributing to differential harmful SiO2NPs effects. Hence, avoidance assays testing SiO2NPs concentrations of 0, 10, 100, 250, 500 and 1000 mg/kg were performed with Enchytraeus crypticus, Folsomia candida, Tenebrio molitor, Porcellionides pruinosus and Eisenia fetida. SiO2NPs induced different behavioral effects, depending on the invertebrate ecology/habitat, exposure route and physiology. T. molitor, P. pruinosus and F. candida did not avoid contaminated soil; however, E. crypticus and E. fetida significantly avoided SiO2NPs spiked soil. Since these terrestrial worms (oligochaetes) live mostly burrowed in the soil, this can provide greater opportunity for SiO2NPs' uptake. On the other hand, the other tested organisms mainly living on the upper part of the soil did not avoid the SiO2NPs spiked soil. The avoidance data obtained here also highlight the need for further studies to understand whether (or not) the detected behavioral responses are linked to either neurotransmission processes or sensorial aspects of the biological models.

4.
Int J Biol Macromol ; 150: 914-921, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32068054

RESUMO

Immunoglobulin G (IgG) has been used in the treatment of cancer, autoimmune diseases and neurological disorders, however, the current technologies to purify and recover IgG from biological media are of high-cost and time-consuming, resulting in high-cost products. In this sense, the search for cost-effective technologies to obtain highly pure and active IgG is highly required. The present work proposes a simple and efficient method for the purification and recovery of IgG from rabbit serum using magnetic iron oxide nanoparticles (magnetite, Fe3O4) coated with hybrid shells of a siliceous material modified with the anionic polysaccharide κ-carrageenan. Experimental parameters such as pH, contact time between the hybrid magnetic nanoparticles (HMNPs) and rabbit serum, and total protein concentration or dilution factor of serum were evaluated. The best results were achieved at pH 5.0, with a contact time of 60 min and using a rabbit serum with a total protein concentration of 4.8 mg·mL-1. Under these conditions, it was obtained an IgG purification factor and adsorption yield onto the HMNPs of 3.0 and 90%, respectively. The desorption of IgG from the HMNPs was evaluated using two strategies: a KCl aqueous solution and buffered aqueous solutions. Comparing to the initial rabbit serum, an IgG purification factor of 2.7 with a recovery yield of 74% were obtained using a buffered aqueous solution at pH 7.0. After desorption, the secondary structure of IgG and other proteins was evaluated by circular dichroism and no changes in the secondary structure were observed, meaning that the IgG integrity is kept after the adsorption and desorption steps. In summary, the application of HMNPs in the purification of IgG from serum samples has a high potential as a new downstream platform.


Assuntos
Carragenina/química , Imunoglobulina G/química , Imunoglobulina G/isolamento & purificação , Nanopartículas de Magnetita/química , Adsorção , Animais , Anticorpos Monoclonais/isolamento & purificação , Concentração de Íons de Hidrogênio , Imunoglobulina G/sangue , Tamanho da Partícula , Coelhos , Água , Difração de Raios X
5.
Materials (Basel) ; 13(3)2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32046064

RESUMO

This work aims at the preparation of multifunctional titania-based photocatalysts with inherent capabilities for thermal co-activation and stabilisation of anatase polymorph, by designing the phase composition and microstructure of rutile-silicon carbide mixture. The processing involved a conventional solid state route, including partial pre-reduction of rutile by SiC in inert Ar atmosphere, followed by post-oxidation in air. The impacts of processing conditions on the phase composition and photocatalytic activity were evaluated using Taguchi planning. The XRD studies confirmed the presence of rutile/anatase mixtures in the post-oxidised samples. The results emphasise that pre-reduction and post-oxidation temperatures are critical in defining the phase composition, while post-oxidation time is relevant for the photocatalytic performance. Microstructural studies revealed the formation of core-shell particles, which can suppress the photocatalytic activity. The highest apparent reaction rate of the photodegradation of methylene blue was observed for the sample pre-reduced in Ar at 1300 °C for 5 h and then calcined in air at 400 °C for 25 h. Though its performance was ~1.6-times lower than that for the same amount of nanostructured industrial P25 photocatalyst, it was achieved in the material possessing 2-3 times lower surface area and containing ~50 mol% of SiO2 and SiC, thus demonstrating excellent prospects for further improvements.

6.
Talanta ; 184: 347-355, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29674052

RESUMO

Bladder Cancer (BC) presents one of the highest recurrence rates amongst solid tumours and constitutes the second deadliest disease of the genitourinary track. Non-invasive identification of patients facing disease recurrence and/or progression remains one of the most critical and challenging aspects in disease management. To contribute to this goal, we demonstrate the potential of glycan-affinity glycoproteomics nanoplatforms for urinary biomarkers discovery in bladder cancer. Briefly, magnetic nanoprobes (MNP) coated with three broad-spectrum lectins, namely Concanavalin A (ConA; MNP@ConA), Wheat Germ Agglutinin (WGA; MNP@WGA), and Sambucus nigra (SNA; MNP@SNA), were used to selectively capture glycoproteins from the urine of low-grade and high-grade non-muscle invasive as well as muscle-invasive BC patients. Proteins were identified by nano-LC MALDI-TOF/TOF and data was curated using bioinformatics tools (UniProt, NetOGlyc, NetNGlyc, ClueGO app for Cytoscape and Oncomine) to highlight clinically relevant species. Accordingly, 63 glycoproteins were exclusively identified in cancer samples compared with healthy controls matching in age and gender. Specific glycoprotein sets exclusively found in low-grade non-muscle invasive bladder tumours may aid early diagnosis, while those only found in high-grade non-invasive and muscle-invasive tumours hold potential for accessing progression. Amongst these proteins is bladder cancer stem-cell marker CD44, which has been associated with poor prognosis. Orthogonal validation studies by slot-blotting demonstrated an elevation in urine CD44 levels of high-grade patients, which became more pronounced upon muscle-invasion, in mimicry of the primary tumour. These observations demonstrate the potential of MNP@lectins for identification of clinically relevant glycoproteomics signatures in bladder cancer. Future clinical validation in a larger and well characterized patient subset is required envisaging clinical translation of the results.


Assuntos
Biomarcadores Tumorais/urina , Glicoproteínas/urina , Nanopartículas de Magnetita/química , Polissacarídeos/química , Neoplasias da Bexiga Urinária/urina , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Ácidos Siálicos/análise
7.
Rev Port Cardiol ; 35(11): 601-616, 2016 Nov.
Artigo em Inglês, Português | MEDLINE | ID: mdl-27712930

RESUMO

The Acute Dialysis Quality Initiative consensus conference proposed a classification of cardiorenal syndrome (CRS), aiming for a better delineation of each subtype. Although the exact pathophysiology of type 4 CRS is not completely understood, the mechanisms involved are probably multifactorial. There is growing evidence that oxidative stress is a major connector in the development and progression of type 4 CRS. Giving its complexity, poor prognosis and increasing incidence, type 4 CRS is becoming a significant public health problem. Patients with chronic kidney disease are particularly predisposed to cardiac dysfunction, due to the high prevalence of traditional cardiovascular risk factors in this population, but the contribution of risk factors specific to chronic kidney disease should also be taken into account. Much remains to be elucidated about type 4 CRS: despite progress over the last decade, there are still significant questions regarding its pathophysiology and there is as yet no specific therapy. A better understanding of the mechanisms involved may provide potential targets for intervention. The present review will provide a brief description of the definition, epidemiology, diagnosis, prognosis, biomarkers and management strategies of type 4 CRS, and the pathophysiological mechanisms and risk factors presumably involved in its development will be particularly highlighted.


Assuntos
Síndrome Cardiorrenal/classificação , Síndrome Cardiorrenal/etiologia , Doenças Cardiovasculares/etiologia , Humanos , Fatores de Risco
8.
Methods Mol Biol ; 1243: 83-100, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25384741

RESUMO

Protein post-translational modifications (PTMs) have increasingly become a research field of incredible importance to fully understand the regulation of biological processes in health and disease. Among PTMs, glycosylation is one of the most studied for which contributed the development and improvement of enrichment techniques. Nowadays, glycoprotein enrichment methods are based on lectin affinity, covalent interactions, and hydrophilic interaction liquid chromatography (HILIC). Nonetheless, the nanotechnology era has fetched new methods to enrich glycoproteins from complex samples as human biological fluids. For instance, magnetic nanoparticles (MNPs) are being used as an interesting enrichment approach allowing a better characterization of glycoproteins and glycopeptides.In this chapter, we describe an enrichment method based on MNPs functionalized with lectins (Concavalin A, wheat germ agglutinin, and Maackia amurensis lectin) to enrich specific sets of glycoproteins from biological fluids. Moreover, it is proposed a bioinformatic strategy to deal with data retrieved from mass spectrometry analysis of enriched samples aiming the identification of relevant biological processes modulated by a given stimuli and, ultimately, of new biomarkers for disease screening/management.


Assuntos
Glicoproteínas/química , Glicoproteínas/metabolismo , Lectinas/metabolismo , Nanopartículas de Magnetita/química , Cromatografia Líquida , Biologia Computacional , Glicoproteínas/sangue , Glicoproteínas/urina , Glicosilação , Humanos , Proteólise , Proteômica , Manejo de Espécimes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
Biotechnol Adv ; 32(5): 952-70, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24858476

RESUMO

Formed as an interdisciplinary domain on the basis of Human Genome Project, Proteomics aims at the large-scale study of proteins. The enthusiasm that resulted from obtaining the complete human genetic information has, however, been chastened by the realization that this information contributes little to the comprehension and knowledge of the expressed proteins. In the wake of this realization, the Human Proteome Project (HUPO) was founded, which is a global, collaborative initiative, aiming at the complete characterization of the proteins of all protein-coding genes. Nonetheless, the rapid detection of these molecules in complex biological samples under conditions considered to be of clinical relevance is extremely difficult, requiring the development of very sensitive, robust, reproducible and high throughput platforms. Nanoproteomics has emerged as a feasible, promising option, offering short assay times, low sample consumption, ultralow detection and high throughput capacity. Additionally, the successful synthesis of biomolecules and nanoparticle hybrids yields systems which often exhibit new or improved features. Herein, we overview the recent advances in bioconjugation at the nanolevel and, specifically, their application in Proteomics, discussing not only the merits and prospects of Proteomics, but also present day limitations.


Assuntos
Materiais Biocompatíveis/química , Nanoestruturas/química , Nanotecnologia/métodos , Proteômica/métodos , Animais , Humanos
10.
Eur J Obstet Gynecol Reprod Biol ; 164(2): 156-60, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22743137

RESUMO

OBJECTIVES: To verify non-inferiority of the clinical pregnancy rate of Early hCG administration (leading follicle sizes within 16.0-16.9 mm in diameter) compared to Late hCG administration (leading follicle sizes within 18.0-18.9 mm in diameter). STUDY DESIGN: Prospective randomized trial. Six hundred and twelve infertile women candidates for intrauterine insemination (IUI) received HP-hMG 75 IU/day SC from cycle days 4 to 8 and then as per ovarian response. Ovulation was randomly triggered (hCG 5000 IU, IM) when the leading follicle diameter ranged between either 16.0 and 16.9 mm (Early hCG group, n=227) or 18.0 and 18.9 mm (Late hCG group, n=207) and IUI was performed approximately 36 h later. RESULTS: Whereas population and sperm characteristics were comparable in both groups, the number of follicles ≥ 14 mm in diameter (P<0.007) and serum estradiol levels (P<0.001) on the day of hCG were lower in the Early versus the Late hCG groups. Clinical (11.9% versus 12.1%) and ongoing (11.0% versus 8.6%) pregnancy rates per randomized women were similar in the two groups and statistical non-inferiority of clinical and ongoing pregnancy rates was demonstrated. CONCLUSION: These results suggest that hCG administered when the largest follicle size reaches 16.0-16.9 mm leads to similar clinical and ongoing pregnancy rates as when it reaches 18.0-18.9 mm in IUI cycles.


Assuntos
Gonadotropina Coriônica/administração & dosagem , Fármacos para a Fertilidade Feminina/administração & dosagem , Infertilidade Feminina/terapia , Inseminação Artificial , Oogênese/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Indução da Ovulação , Adulto , Gonadotropina Coriônica/farmacologia , Estradiol/sangue , Feminino , Fármacos para a Fertilidade Feminina/farmacologia , Humanos , Infertilidade/sangue , Infertilidade/terapia , Infertilidade Feminina/sangue , Masculino , Menotropinas/farmacologia , Tamanho do Órgão/efeitos dos fármacos , Folículo Ovariano/anatomia & histologia , Folículo Ovariano/diagnóstico por imagem , Gravidez , Taxa de Gravidez , Equivalência Terapêutica , Ultrassonografia , Adulto Jovem
11.
Fertil Steril ; 96(5): 1062-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22036049

RESUMO

OBJECTIVE: To review and summarize data from the scientific literature on the use of androgens to improve ovarian function. DESIGN: Review of pertinent literature. SETTING: University hospital. PATIENT(S): Women exposed to androgens. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Critical review of the literature. RESULT(S): The artificial increase of intra-ovarian androgen concentrations constitutes an attractive concept for improving the deficient ovarian function of poor responders. Data from studies conducted in animals treated with high-dose androgens, together with observations made in hyperandrogenic women or female-to-male transsexuals receiving virilizing androgen doses, indicate that androgens may increase follicle responsiveness to FSH and/or the number of growing follicles in the ovary. Yet, definite clinical demonstration of such a concept still is not available. CONCLUSION(S): Current clinical approaches aiming at increasing androgen availability in the ovary showed conflicting results. Therefore, additional studies using proper strategies to achieving higher intra-ovarian androgen concentrations for longer intervals are required to define the clinical efficiency of androgens in poor responders.


Assuntos
Androgênios/uso terapêutico , Fármacos para a Fertilidade Feminina/uso terapêutico , Infertilidade/terapia , Folículo Ovariano/efeitos dos fármacos , Indução da Ovulação/métodos , Ovulação/efeitos dos fármacos , Animais , Feminino , Humanos , Hiperandrogenismo/fisiopatologia , Infertilidade/fisiopatologia , Masculino , Folículo Ovariano/fisiopatologia , Gravidez , Procedimentos de Readequação Sexual , Transexualidade/fisiopatologia , Transexualidade/terapia , Falha de Tratamento , Virilismo/fisiopatologia
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