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1.
Front Mol Neurosci ; 17: 1459083, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39386050

RESUMO

The Transient Receptor Potential (TRP) constitutes a family of channels subdivided into seven subfamilies: Ankyrin (TRPA), Canonical (TRPC), Melastatin (TRPM), Mucolipin (TRPML), no-mechano-potential C (TRPN), Polycystic (TRPP), and Vanilloid (TRPV). Although they are structurally similar to one another, the peculiarities of each subfamily are key to the response to stimuli and the signaling pathway that each one triggers. TRPs are non-selective cation channels, most of which are permeable to Ca2+, which is a well-established second messenger that modulates several intracellular signaling pathways and is involved in physiological and pathological conditions in various cell types. TRPs depolarize excitable cells by increasing the influx of Ca2+, Na+, and other cations. Most TRP families are activated by temperature variations, membrane stretching, or chemical agents and, therefore, are defined as polymodal channels. All TPRs are expressed, at some level, in the central nervous system (CNS) and ocular-related structures, such as the retina and optic nerve (ON), except the TRPP in the ON. TRPC, TRPM, TRPV, and TRPML are found in the retinal pigmented cells, whereas only TRPA1 and TRPM are detected in the uvea. Accordingly, several studies have focused on the search to unravel the role of TRPs in physiological and pathological conditions related to the eyes. Thus, this review aims to shed light on endogenous and exogenous modulators, triggered cell signaling pathways, and localization and roles of each subfamily of TRP channels in physiological and pathological conditions in the retina, optic nerve, and retinal pigmented epithelium of vertebrates.

2.
Anal Chem ; 96(40): 15852-15858, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39236255

RESUMO

Three-dimensional (3D) printing is an emerging technology to develop devices on a large scale with potential application for electroanalysis. However, 3D-printed electrodes, in their native form, provide poor electrochemical response due to the presence of a high percentage of thermoplastic polymer in the conductive filaments. Therefore, surface treatments are usually required to remove the nonconductive material from the 3D-printed electrode surfaces, providing a dramatic improvement in the electroanalytical performance. However, these procedures are time-consuming, require bulky equipment, or even involve non-eco-friendly protocols. Herein, we demonstrated that portable and low-cost atmospheric air plasma jet pens can be used to activate electrodes additively manufactured using a commercial poly(lactic acid) filament containing carbon black as conductive filler, improving the electrochemical activity. Remarkable electrochemical results were obtained (voltammetric profile) using [Fe(CN)6]3-/4-, dopamine and [Ru(NH3)6]2+/3+ as redox probes. Microscopic, spectroscopic, and electrochemical techniques revealed that the air-plasma jet pen removes the excess PLA on the 3D-printed electrode surface, exposing the conductive carbon black particles and increasing the surface area. The performance of the treated electrode was evaluated by the quantification of capsaicin in pepper sauce samples, with a limit of detection of 3 nM, suitable for analysis of food samples. Recovery values from 94% to 101% were obtained for the analysis of spiked samples. The new treatment generated by a plasma jet pen is an alternative approach to improve the electrochemical activity of 3D-printed electrodes that present sluggish kinetics with great advantages over previous protocols, including low-cost, short time of treatment (2 min), environmentally friendly protocol (reagentless), and portability (hand-held pen).

3.
Acta Ortop Bras ; 32(3): e276513, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39086848

RESUMO

Objective: Throughout microsurgical anastomosis, many surgeons use topical vasodilators in order to reduce pathological vasospasm. It was carried out an experimental study comparing the effectiveness of topical use of Nitroglycerin, Papaverine, Magnesium sulfate over a control group in the femoral artery and vein of rats, in reducing prolonged vasospasm. Methods: Randomized comparative experimental study in 15 rats, divided into four groups. The external diameter of the vases soaked in the randomized solution was measured. For statistical analysis, it was calculated the percentual increase in the external diameter of the vessels. Results: A statistically significant increase in arterial dilation was observed after 10 minutes of topical application of 10% magnesium sulfate compared to the control group, with p = 0.044 . No other drug showed a vasodilator effect superior to the control group. Magnesium sulfate at 10% is still not used in microsurgery and costs 15 times less than papaverine, the standard drug for topical vasodilation in clinical cases at our service. Conclusion: Magnesium sulfate had better vasodilating effects over the control group after 10 minutes of arterial microanastomosis. None of the tested drugs have presented superior vasodilating effects over each other nor the control group after venous microanastomosis. Level of evidence II, Experimental study, Randomized Trial.


Objetivo: Durante a anastomose microcirúrgica, muitos cirurgiões utilizam vasodilatadores tópicos para reduzir o vasoespasmo prolongado patológico, assim reduzindo o risco de complicações vasculares. Entretanto, ainda faltam dados experimentais para identificação da droga padrão-ouro para vasodilatadores tópicos em microcirurgia e sua avaliação de análise de custo, já que a droga geralmente utilizada para este objetivo é baseada, na maior parte dos casos, na experiência do cirurgião. Métodos: Foi realizado um estudo experimental comparativo randomizado, avaliando a eficácia do uso tópico de Nitroglicerina, Papaverina e Sulfato de Magnésio em relação a um grupo controle, na redução do vasoespasmo na artéria e veia femoral de ratos. Foram avaliados o diâmetro externo dos vasos embebidos em solução randomizada dos fármacos para vasodilatação. Após cálculo do aumento percentual no diâmetro externo dos vasos, foi realizada análise estatística. Resultados: Observou-se aumento estatisticamente significativo da dilatação arterial após 10 minutos de aplicação tópica de sulfato de magnésio a 10% em relação ao grupo controle, com p = 0,044. Nenhuma outra droga apresentou efeito vasodilatador superior ao grupo controle. O sulfato de magnésio a 10% ainda não é utilizado em microcirurgia e apresenta custo até 15 vezes menor quando comparado com a papaverina, droga padrão para vasodilatação tópica em casos clínicos em nosso serviço. Conclusão: O sulfato de magnésio apresentou melhor efeito vasodilatador quando comparado ao grupo controle, após 10 minutos da microanastomose arterial. Nenhum dos fármacos testados apresentou efeito vasodilatador superior após a microanastomose venosa. Nível de Evidência II, Estudo experimental, Ensaio Randomizado.

4.
Vitam Horm ; 125: 183-229, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38997164

RESUMO

Hemoglobin (Hb) is a hemeprotein found inside erythrocytes and is crucial in transporting oxygen and carbon dioxide in our bodies. In erythrocytes (Ery), the main energy source is glucose metabolized through glycolysis. However, a fraction of Hb can undergo glycation, in which a free amine group from the protein spontaneously binds to the carbonyl of glucose in the bloodstream, resulting in the formation of glycated hemoglobin (HbA1c), widely used as a marker for diabetes. Glycation leads to structural and conformational changes, compromising the function of proteins, and is intensified in the event of hyperglycemia. The main changes in Hb include structural alterations to the heme group, compromising its main function (oxygen transport). In addition, amyloid aggregates can form, which are strongly related to diabetic complications and neurodegenerative diseases. Therefore, this chapter discusses in vitro protocols for producing glycated Hb, as well as the main techniques and biophysical assays used to assess changes in the protein's structure before and after the glycation process. This more complete understanding of the effects of glycation on Hb is fundamental for understanding the complications associated with hyperglycemia and for developing more effective prevention and treatment strategies.


Assuntos
Hemoglobinas , Humanos , Glicosilação , Hemoglobinas/metabolismo , Hemoglobinas/química , Hemoglobinas Glicadas/metabolismo , Conformação Proteica , Animais
5.
Foods ; 13(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38928788

RESUMO

The present review highlights the potential of insect-based proteins to address the growing need for sustainable and secure food systems. The key findings suggest that edible insects offer a viable and environmentally friendly alternative to traditional livestock, requiring significantly less land, water, and feed while emitting lower levels of greenhouse gases. Insect farming can also reduce waste and recycle nutrients, supporting circular economy models. Nutritionally, insects provide high-quality protein, essential amino acids, and beneficial fats, making them valuable to human diets. Despite these benefits, this review emphasizes the need for comprehensive regulatory frameworks to ensure food safety, manage potential allergenicity, and mitigate contamination risks from pathogens and environmental toxins. Additionally, developing innovative processing technologies can enhance the palatability and marketability of insect-based products, promoting consumer acceptance. This review concludes that with appropriate regulatory support and technological advancements, insect-based proteins have the potential to significantly contribute to global food security and sustainability efforts.

6.
Foods ; 13(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38540806

RESUMO

This study explores the influence of hydrocolloid interactions between Guar Gum (GG) and Xanthan Gum (XG) on the stability and release dynamics of essential thyme oil emulsions. We systematically characterized six emulsions with varying GG and XG ratios, employing spray-drying techniques for the encapsulation process. The stability of the emulsions was quantitatively analyzed, revealing a marked decrease in stability rates correlated with higher initial emulsion activity (zero-order kinetic constant r = -0.972). Furthermore, this study demonstrated that emulsions with carefully optimized hydrocolloid ratios could achieve high encapsulation efficiency (74%) and controlled release profiles. Kinetic modeling and diffusion analyses elucidated that increased XG concentrations tend to reduce diffusivity, thereby enhancing emulsion stability. The effective diffusivity of the thyme oil within the emulsion matrix was determined to be within a range of 0.7 to 2.4 × 10-10 m2/s, significantly influencing release kinetics. The Pearson correlation matrix underlined a substantial negative association between emulsion activity and effective diffusivity (r = -0.740), indicating that denser hydrocolloid networks impede oil mobility. The findings conclusively establish that the interplay of GG and XG concentrations is pivotal in dictating the emulsion's physicochemical properties, with denser networks formed by higher XG content leading to slower oil release rates and enhanced stability. This research provides critical insights for the design of encapsulated food and pharmaceutical products, highlighting the imperative of strategic hydrocolloid selection to realize specific functional attributes and performance criteria.

7.
Am J Med Genet A ; : e63602, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517102

RESUMO

Ramon syndrome (OMIM #266270) was first described in a patient with cherubism, gingival fibromatosis, epilepsy, intellectual disability, hypertrichosis, and stunted growth. In 2018, Mehawej et al. described a patient with Ramon syndrome in whom a homozygous variant in ELMO2 was identified, suggesting that this gene may be the causative for this syndrome. ELMO2 biallelic pathogenic variants were also described in patients with a primary intraosseous vascular malformation (PIVM; OMIM #606893). These patients presented gingival bleeding and cherubism phenotype. Herein, a patient with gingival hypertrophy, neurodevelopmental delay, and cherubism phenotype with a novel homozygous predicted loss-of-function (LOF) variant in the ELMO2 gene and family recurrence was reported. A surgical approach to treat gingival bleeding and mandible vascular malformation was also described. Furthermore, this study includes a comprehensive literature review of molecular data regarding the ELMO2 gene. All the variants, except one described in the ELMO2, were predicted as LOF, including our patient's variant. There is an overlapping between PIVM, also caused by LOF biallelic variants in the ELMO2 gene, and Ramon syndrome, which can suggest that they are not different entities. However, due to a limited number of cases described with molecular evaluation, it is hard to establish a genotype-phenotype correlation. Our study supports that LOF pathogenic biallelic variants in the ELMO2 gene cause a phenotype that has cherubism and gingival hypertrophy as main characteristics.

8.
Environ Sci Pollut Res Int ; 31(13): 20172-20187, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38369661

RESUMO

Tetracycline (TC) is a widely used antibiotic, and evaluating its interaction with humic substances (HS) that act as a complexing agent in the environment is essential to understanding the availability of this contaminant in the environment. This study evaluated the interaction between HS and TC using different spectroscopic techniques, theoretical studies, and biological assays simulating environmental conditions. TC interacts with HS, preferably by electrostatic forces, with a binding constant of 9.2 × 103 M-1 (30 °C). This process induces conformational changes in the superstructure, preferably in the HS, like protein fraction. Besides, studies using the 8-anilino-1-naphthalene sulfonate (ANS) probe indicated that the antibiotic alters the hydrophobicity degree on HS's surface. Synchronized fluorescence shows that the TC interaction occurs preferentially with the protein-like fraction of soil organic matter (KSV = 26.28 ± 1.03 M-1). The TC epitope was evaluated by 1H NMR and varied according to the pH (4.8 and 9.0) of the medium, as well as the main forces responsible for the stabilization of the HS-TC complex. The molecular docking studies showed that the formation of the HS-TC complex is carried out spontaneously (ΔG = -7.1 kcal mol-1) and is stabilized by hydrogen bonds and electrostatic interactions, as observed in the experimental spectroscopic results. Finally, biological assays indicated that HS influenced the antimicrobial activity of TC. Thus, this study contributed to understanding the dynamics and distribution of TC in the environment and HS's potential in the remediation of antibiotics of this class in natural systems, as these can have adverse effects on ecosystems and human health.


Assuntos
Ecossistema , Substâncias Húmicas , Humanos , Substâncias Húmicas/análise , Simulação de Acoplamento Molecular , Adsorção , Antibacterianos/farmacologia , Antibacterianos/química , Tetraciclina/química
9.
Children (Basel) ; 11(2)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38397303

RESUMO

Currently, there is no intervention model for autism spectrum disorder (ASD) that addresses all levels and factors of the International Classification of Functioning, Disability and Health (ICF, WHO). The most researched programs focus on naturalistic, developmental and behavioral approaches to socio-communication. Less attention has been paid to motor and environmental reactivity aspects (behavior/interest restriction and sensory reactivity). The evidence rationale for the Global Integration Method (MIG, "Método de Integração Global"), a model addressing sensorimotor reactivity in addition to socio-communication, is presented. MIG is an integrative, interdisciplinary, family-oriented intervention and naturalistic program that addresses all levels and moderating factors of ASD's impact. MIG's theoretical rationale is based on the predictive coding impairment and embodied cognition hypotheses. MIG incorporates both bottom-up (flexible therapeutic suit, social-motor synchronization) and top-down (schematic social information processing, narratives, imagery) strategies to promote the building and use of accurate, flexible and context-sensitive internal predictive models. MIG is based on the premises that predictive coding improves both socio-communication and environmental reactivity, and that the postural stabilization provided by the flexible therapeutic suit frees information processing resources for socio-cognitive learning. MIG builds on interdisciplinary, professionally and parentally mediated work based on behavioral principles of intensive training in a situated environment.

10.
Rev. Baiana Saúde Pública (Online) ; 47(4): 238-254, 20240131.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1537823

RESUMO

Species of Pithecellobium (Fabaceae) are used in traditional medicine to treat diabetes, cough, bronchitis, and inflammation. This study aims to evaluate the content and determine the antioxidant activity, phenolic compounds content, and cytotoxicity of the extract and the fractions of Pithecellobium diversifolium. This is unprecedented research with an exotic species from the Caatinga, northeastern Brazil, using High-performance Liquid Chromatography-Electrospray Ionization-Mass Spectrometry (HPLC-ESI-MS). The MeOH fractions of leaves and stem barks showed a high content of flavonoids (198.1 ± 106.50 and 542.7 ± 2.52 mg EqQ/g). The CH2Cl2 fraction of peels showed a high content of total phenolic compounds (516.7 ± 3.00 mg EqAG /g). The DPPH test showed that the CH2Cl2 fraction (leaves) held an EC50 of 0.08 ± 0.02, a higher value than that observed for the standards used in the test­Butylated hydroxyanisole (BHA), Butylated hydroxytoluene (BHT), and ascorbic acid. The AcOEt and MeOH fractions of peels presented moderate cytotoxicity with values below 500 µg/mL. The MeOH fraction of leaves showed seven major compounds: myricetin, quercetin, quercetin-arabinofuranoside, apigenin-triglycosides, and apigenin-diglucoside, being the last three unpublished in studies involving the genus. The tests conducted in this study show the potential of P. diversifolium as a promising source of biomolecules with therapeutic applicability.


Espécies de Pithecellobium (Fabaceae) são usadas na medicina tradicional para tratar diabetes, tosse, bronquite e inflamação. Este estudo teve como objetivo avaliar o teor e determinar a atividade antioxidante, o teor de compostos fenólicos e a citotoxicidade do extrato e das frações de Pithecellobium diversifolium, uma pesquisa inédita com uma espécie exótica da Caatinga do Nordeste do Brasil, utilizando a instrumentação Clae-IES. As frações MeOH das folhas e cascas do caule apresentaram alto teor de flavonoides (198,1 ± 106,50 e 542,7 ± 2,52 mg EqQ/g). A fração CH2Cl2 das cascas apresentou um elevado teor de compostos fenólicos totais (516,7 ± 3,00 mg EqAG/g). O teste DPPH mostrou que a fração CH2Cl2 (folhas) apresentou um EC50 de 0,08 ± 0,02, valor superior ao observado para os padrões utilizados no teste ­ Butil hidroxianisol (BHA), Butil hidroxitolueno (BHT) e ácido ascórbico. As frações AcOEt e MeOH das cascas apresentaram citotoxicidade moderada com valores inferiores a 500 µg/mL. A fração MeOH das folhas apresentou sete compostos majoritários: miricetina, quercetina, quercetina-arabinofuranosídeo, apigenina-triglicosídeos e apigenina-diglucosídeo, sendo os três últimos inéditos em estudos envolvendo o gênero. Os testes realizados demonstram o potencial de P. diversifolium, uma promissora fonte de biomoléculas com aplicabilidade terapêutica.


Las especies de Pithecellobium (Fabaceae) se utilizan en la medicina tradicional para tratar diabetes, tos, bronquitis e inflamación. Este estudio tuvo como objetivo evaluar el contenido y determinar la actividad antioxidante, el contenido de compuestos fenólicos y la citotoxicidad del extracto y de las fracciones de Pithecellobium diversifolium, un estudio inédito con una especie exótica de la Caatinga de la región Nordeste de Brasil, que utilizó la instrumentación HPLC-ESI. Las fracciones MeOH de hojas y cortezas de tallo mostraron un alto contenido de flavonoides (198,1 ± 106,50 y 542,7 ± 2,52 mg EqQ/g). La fracción CH2Cl2 de las cortezas presentó un alto contenido de compuestos fenólicos totales (516,7 ± 3,00 mg EqAG/g). El ensayo DPPH mostró que la fracción CH2Cl2 (hojas) tenía EC50 de 0,08 ± 0,02, valor superior a lo observado para los estándares utilizados en el ensayo ­Butilhidroxianisol (BHA), butilhidroxitolueno (BHT) y ácido ascórbico. Las fracciones AcOEt y MeOH de las cortezas presentaron una citotoxicidad moderada con valores inferiores a 500 µ g/mL. La fracción MeOH de las hojas contiene siete compuestos principales: miricetina, quercetina, quercetina-arabinofuranosido, apigenina-triglucósidos y apigenina-diglucósido, de los cuales los tres últimos son inéditos en estudios sobre el género. Las pruebas realizadas demuestran el potencial de P. diversifolium, una fuente prometedora de biomoléculas con aplicabilidad terapéutica.

11.
Acta ortop. bras ; Acta ortop. bras;32(3): e276513, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1563680

RESUMO

ABSTRACT Objective: Throughout microsurgical anastomosis, many surgeons use topical vasodilators in order to reduce pathological vasospasm. It was carried out an experimental study comparing the effectiveness of topical use of Nitroglycerin, Papaverine, Magnesium sulfate over a control group in the femoral artery and vein of rats, in reducing prolonged vasospasm. Methods: Randomized comparative experimental study in 15 rats, divided into four groups. The external diameter of the vases soaked in the randomized solution was measured. For statistical analysis, it was calculated the percentual increase in the external diameter of the vessels. Results: A statistically significant increase in arterial dilation was observed after 10 minutes of topical application of 10% magnesium sulfate compared to the control group, with p = 0.044 . No other drug showed a vasodilator effect superior to the control group. Magnesium sulfate at 10% is still not used in microsurgery and costs 15 times less than papaverine, the standard drug for topical vasodilation in clinical cases at our service. Conclusion: Magnesium sulfate had better vasodilating effects over the control group after 10 minutes of arterial microanastomosis. None of the tested drugs have presented superior vasodilating effects over each other nor the control group after venous microanastomosis. Level of evidence II, Experimental study, Randomized Trial.


RESUMO Objetivo: Durante a anastomose microcirúrgica, muitos cirurgiões utilizam vasodilatadores tópicos para reduzir o vasoespasmo prolongado patológico, assim reduzindo o risco de complicações vasculares. Entretanto, ainda faltam dados experimentais para identificação da droga padrão-ouro para vasodilatadores tópicos em microcirurgia e sua avaliação de análise de custo, já que a droga geralmente utilizada para este objetivo é baseada, na maior parte dos casos, na experiência do cirurgião. Métodos: Foi realizado um estudo experimental comparativo randomizado, avaliando a eficácia do uso tópico de Nitroglicerina, Papaverina e Sulfato de Magnésio em relação a um grupo controle, na redução do vasoespasmo na artéria e veia femoral de ratos. Foram avaliados o diâmetro externo dos vasos embebidos em solução randomizada dos fármacos para vasodilatação. Após cálculo do aumento percentual no diâmetro externo dos vasos, foi realizada análise estatística. Resultados: Observou-se aumento estatisticamente significativo da dilatação arterial após 10 minutos de aplicação tópica de sulfato de magnésio a 10% em relação ao grupo controle, com p = 0,044. Nenhuma outra droga apresentou efeito vasodilatador superior ao grupo controle. O sulfato de magnésio a 10% ainda não é utilizado em microcirurgia e apresenta custo até 15 vezes menor quando comparado com a papaverina, droga padrão para vasodilatação tópica em casos clínicos em nosso serviço. Conclusão: O sulfato de magnésio apresentou melhor efeito vasodilatador quando comparado ao grupo controle, após 10 minutos da microanastomose arterial. Nenhum dos fármacos testados apresentou efeito vasodilatador superior após a microanastomose venosa. Nível de Evidência II, Estudo experimental, Ensaio Randomizado.

12.
Hum Genomics ; 17(1): 102, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37968704

RESUMO

BACKGROUND: Next-generation sequencing has had a significant impact on genetic disease diagnosis, but the interpretation of the vast amount of genomic data it generates can be challenging. To address this, the American College of Medical Genetics and Genomics and the Association for Molecular Pathology have established guidelines for standardized variant interpretation. In this manuscript, we present the updated Hospital Israelita Albert Einstein Standards for Constitutional Sequence Variants Classification, incorporating modifications from leading genetics societies and the ClinGen initiative. RESULTS: First, we standardized the scientific publications, documents, and other reliable sources for this document to ensure an evidence-based approach. Next, we defined the databases that would provide variant information for the classification process, established the terminology for molecular findings, set standards for disease-gene associations, and determined the nomenclature for classification criteria. Subsequently, we defined the general rules for variant classification and the Bayesian statistical reasoning principles to enhance this process. We also defined bioinformatics standards for automated classification. Our workgroup adhered to gene-specific rules and workflows curated by the ClinGen Variant Curation Expert Panels whenever available. Additionally, a distinct set of specifications for criteria modulation was created for cancer genes, recognizing their unique characteristics. CONCLUSIONS: The development of an internal consensus and standards for constitutional sequence variant classification, specifically adapted to the Brazilian population, further contributes to the continuous refinement of variant classification practices. The aim of these efforts from the workgroup is to enhance the reliability and uniformity of variant classification.


Assuntos
Testes Genéticos , Variação Genética , Humanos , Estados Unidos , Mutação , Reprodutibilidade dos Testes , Teorema de Bayes , Genoma Humano
13.
Braz J Microbiol ; 54(4): 2845-2856, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37904004

RESUMO

The high incidence of multidrug-resistant (MDR) Acinetobacter baumannii has been a challenge for health worldwide, due to the reduction of therapeutic options, making the use of antimicrobial combinations necessary for the treatment, such as meropenem, amikacin, and colistin. Antibodies against bacterial species, mainly immunoglobulins G (IgG), are produced for acting as effector mechanisms (neutralization, opsonization, phagocytosis, and complement system activation). Some studies have demonstrated promising results of IgG in combination with antimicrobial preparations against bacterial infections, in which the direct action of IgG has restored the immune system balance. Serious problem caused by the increase of MDR A. baumannii isolates results in a constant search for therapeutic alternatives to defeat these infections. However, this study aims to verify in vitro the phagocytosis rate of the A. baumannii-infected human monocytes, as well as to analyze possible morphological changes induced by intravenous immunoglobulin G (IVIG) with human serum in association with antimicrobials. The phagocytosis rate and bacterial cell binding capacity of IVIG were determined for two A. baumannii isolates submitted to 4 mg/mL of human IVIG alone and in combination with different sub-minimum inhibitory concentrations (sub-MICs) of meropenem, amikacin, and colistin and processed for indirect immunofluorescence. Subsequently, these isolates were resubmitted and coupled with human serum and processed for scanning electron microscopy. There was no statistical difference for phagocytosis rates in the isolates tested. Bacterial isolates showed alterations in cell morphology when exposed to IVIG/human serum alone and in combination with antimicrobials such as alteration in shape, wrinkling, membrane depression, and especially cell rupture with extravasation of cytoplasmic material. The isolates visually differed in the IVIG binding to the bacterial cell, with higher fluorescence intensity, which corresponds to the highest IVIG binding, in the isolate more sensitive to meropenem, amikacin, and colistin. No differences between treatments were observed in the IVIG binding to the bacterial cell. The combined action of IVIG with meropenem, amikacin, and colistin against A. baumannii MDR isolates induced several bacterial cell damages. And when associated with human serum, a massive destruction of cells can be observed. These results may suggest the analysis of the use of IgG preparations for the treatment of A. baumannii MDR infections.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Anti-Infecciosos , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Imunoglobulinas Intravenosas/farmacologia , Imunoglobulinas Intravenosas/uso terapêutico , Meropeném/farmacologia , Meropeném/uso terapêutico , Colistina/farmacologia , Amicacina/farmacologia , Amicacina/uso terapêutico , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/microbiologia , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico
15.
Food Res Int ; 173(Pt 1): 113222, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803540

RESUMO

This work describes the kinetic study of different types (spontaneous, lactic and alcoholic) of açai fermentation in terms of total phenolics and total anthocyanins, as well as antioxidant capacity, before and after simulated digestion (SD). Cytotoxicity (A549, HCT8 and IMR90 cells) and formation of reactive oxygen species (A549 cells) were also evaluated. The results revealed that spontaneous fermentation (SF) for 24 h, followed by SD, generated a product with greater bioaccessibility of phenolics (52.68%) and cyanidin-3-glucoside (27.01%) than unfermented açai. Likewise, lactic fermentation (LF) for 72 h improved the bioavailability of phenolics (64.49%) and cyanidin-3-rutinoside (20.00%). On the other hand, alcoholic fermentation (AF) decreased the bioaccessibility of phenolic compounds and anthocyanins after SD. The SF 24 h (10.16 ± 1.25 µmol Trolox /g) and LF 72 h (15.90 ± 0.51 µmol Trolox /g) significantly increased the antioxidant capacity after SD, when compared to unfermented açai (SF 0 h, 4.00 ± 0.09 µmol Trolox /g; LF 0 h, 10.57 ± 0.91 µmol Trolox /g). It was concluded that the samples did not show cytotoxicity in the cell lines tested and, in addition, AF 24 h showed antioxidant and antimutagenic effects in vitro, reducing about 40% of chromosomal aberrations. The results obtained provide important information that can be used to produce foods with greater bioaccessibility of bioactive compounds.


Assuntos
Antocianinas , Antioxidantes , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Antocianinas/metabolismo , Fermentação , Fenóis/metabolismo , Digestão
16.
Mem Inst Oswaldo Cruz ; 118: e220295, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37878830

RESUMO

BACKGROUND: Trypanosoma cruzi, which causes Chagas disease (CD), is a versatile haemoparasite that uses several strategies to evade the host's immune response, including adipose tissue (AT), used as a reservoir of infection. As it is an effective barrier to parasite evasion, the effectiveness of the drug recommended for treating CD, Benznidazole (BZ), may be questionable. OBJECTIVE: To this end, we evaluated the parasite load and immunomodulation caused by BZ treatment in the culture of adipocytes differentiated from human adipose tissue-derived stem cells (ADSC) infected with T. cruzi. METHODS: The ADSC were subjected to adipogenic differentiation. We then carried out four cultures in which we infected the differentiated AT with trypomastigote forms of the Y strain of T. cruzi and treated them with BZ. After the incubation, the infected AT was subjected to quantitative polymerase chain reaction (qPCR) to quantify the parasite load and transmission electron microscopy (TEM) to verify the infection. The supernatant was collected to measure cytokines, chemokines, and adipokines. FINDINGS: We found elevated secretion of IL-6, CXCL-10/IP-10, CCL2/MCP-1, CCL5/RANTES, and leptin in infected fat cells. However, treatment with BZ promoted a decrease in IL-6. MAIN CONCLUSION: Therefore, we believe that BZ has a beneficial role as it reduces inflammation in infected fat cells.


Assuntos
Doença de Chagas , Nitroimidazóis , Tripanossomicidas , Trypanosoma cruzi , Humanos , Interleucina-6 , Doença de Chagas/parasitologia , Nitroimidazóis/farmacologia , Nitroimidazóis/uso terapêutico , Tecido Adiposo , Adipócitos , Diferenciação Celular , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico
17.
Antioxidants (Basel) ; 12(9)2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37760048

RESUMO

The encapsulation of bioactive compounds, which spans phytochemicals, vitamins, antioxidants, and other precious substances, has risen to prominence as a crucial area of interest spanning various domains, including food, pharmaceuticals, and cosmetics. This investigation delved into the efficacy of distinct wall materials-whey protein isolate, high methoxy pectin, and gum arabic-when employed individually or in combination to encapsulate and preserve phenolic compounds and antioxidants during storage. The encapsulation process involved spray-drying bioactive compounds extracted from grapes. Over a span of 120 days, the stability of these encapsulated compounds was meticulously evaluated, encompassing assessments via different antioxidant capacity assays, phenolic content analyses, and high-performance liquid chromatography measurements. The modeling of retention kinetics during storage facilitated the comprehension of the release mechanisms. Notably, the findings underscore the pivotal role of wall materials in preserving these bioactive compounds, with each material or combination of materials exhibiting varying degrees of protective capacity. Remarkably, the synergistic blend of whey protein, pectin, and gum arabic showcased the utmost retention of bioactive compounds over this study's period. The amassed data distinctly show that an amalgamation of wall materials can indeed considerably enhance the stability of encapsulated bioactive compounds, presenting promising applications within the realms of both the food and pharmaceutical industries.

18.
Chemosphere ; 339: 139688, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37532198

RESUMO

In environmental systems, the soil is a principal route of contamination by various potentially toxic species. Roxarsone (RX) is an arsenic (V) organic compound used to treat parasitic diseases and as an additive for animal fattening. When the animal excretes RX, the residues may lead to environmental contamination. Due to their physicochemical properties, the soil's humic substances (HS) are important in species distribution in the environment and are involved in various specific interaction/adsorption processes. Since RX, an arsenic (V) compound, is considered an emerging contaminant, its interaction with HS was evaluated in simulated environmental conditions. The HS-RX interaction was analyzed by monitoring intrinsic HS fluorescence intensity variations caused by complexation with RX, forming non-fluorescent supramolecular complexes that yielded a binding constant Kb (on the order of 103). The HS-RX interaction occurred through static quenching due to complex formation in the ground state, which was confirmed by spectrophotometry. The process was spontaneous (ΔG < 0), and the predominant interaction forces were van der Waals and hydrogen bonding (ΔH < 0 and ΔS < 0), with an electrostatic component evidenced by the influence of ionic strength in the interaction process. Structural changes in the HS were verified by synchronized and 3D fluorescence, with higher variation in the region referring to the protein-like fraction. In addition, metal ions (except ions Cu(II)) favored HS-RX interaction. When interacting with HS, the RX epitope was suggested by 1H NMR, which indicated that the entire molecule interacts with the superstructure. An enzyme inhibition assay verified the ability to reduce the alkaline phosphatase activity of free and complexed RX (RX-HS). Finally, this work revealed the main parameters associated with HS and RX interaction in simulated environmental conditions, thus, providing data that may help our understanding of the dynamics of organic arsenic-influenced soils.


Assuntos
Arsênio , Roxarsona , Poluentes do Solo , Animais , Substâncias Húmicas/análise , Solo/química , Roxarsona/química , Poluentes do Solo/análise , Íons
19.
Parasite Immunol ; 45(6): e12983, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37066749

RESUMO

Benznidazole (Bz) is the recommended drug for the treatment of Chagas disease; however, its efficacy may vary according to the sensitivity of Trypanosoma cruzi strains to the drug and host immune background. The study evaluated the immune response of peripheral blood mononuclear cells (PBMC) that were infected in vitro with the Colombian strain (Col) and treated with Bz. The co-cultures were incubated for 24 h, 5 and 10 days, where cytokine dosage was performed in the supernatant and evaluation of the cells for CD28+ and CTLA-4+ molecules in CD4+ and CD8+ lymphocytes, and CD80+ , CD86+ and HLA-DR+ in CD14+ cells. The results showed that Col induced a strong inflammatory response, with an increase in IFN-γ and TNF early in the infection (24 h), however, from 5 days of infection on, TNF production declined, and IL-10 production increased, which may be associated with a control mechanism of the exacerbated inflammatory response. The Bz treatment did not significantly alter the frequencies of the phenotypes evaluated both T cell subsets and CD14+ cells. Therefore, this study reinforces the need for typing the patient's strain to guide therapy and promote individualized treatment protocols due to the heterogeneous genetic background among T. cruzi strains.


Assuntos
Doença de Chagas , Nitroimidazóis , Tripanossomicidas , Trypanosoma cruzi , Humanos , Leucócitos Mononucleares , Colômbia , Nitroimidazóis/farmacologia , Nitroimidazóis/uso terapêutico , Doença de Chagas/tratamento farmacológico , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico
20.
J Enzyme Inhib Med Chem ; 38(1): 67-83, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36305291

RESUMO

Bacterial infections have become a global concern, stimulating the growing demand for natural and biologically safe therapeutic agents with antibacterial action. This study was evaluated the genotoxicity of the trypsin inhibitor isolated from tamarind seeds (TTI) and the antibacterial effect of TTI theoric model, number 56, and conformation number 287 (TTIp 56/287) and derived peptides in silico. TTI (0.3 and 0.6 mg.mL-1) did not cause genotoxicity in cells (p > 0.05). In silico, a greater interaction of TTIp 56/287 with the Gram-positive membrane (GP) was observed, with an interaction potential energy (IPE) of -1094.97 kcal.mol-1. In the TTIp 56/287-GP interaction, the Arginine, Threonine (Thr), and Lysine residues presented lower IPE. In molecular dynamics (MD), Peptidotrychyme59 (TVSQTPIDIPIGLPVR) showed an IPE of -518.08 kcal.mol-1 with the membrane of GP bacteria, and the Thr and Arginine residues showed the greater IPE. The results highlight new perspectives on TTI and its derived peptides antibacterial activity.


Assuntos
Tamarindus , Inibidores da Tripsina , Inibidores da Tripsina/farmacologia , Tamarindus/química , Peptídeos/química , Sementes/química , Antibacterianos/farmacologia , Antibacterianos/análise , Arginina/análise , Arginina/química
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