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1.
Food Res Int ; 182: 114162, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38519186

RESUMEN

Whey is a by-product derived from cheese making. Despite being rich in nutrients, it is little used, it even represents a problem form the environment in Mexico. In this sense, it is important to know the meanings that are associated with this term, especially when it is intended to develop new products from this by-product. The objective of this work was to analyze the representation of the term whey in rural and urban populations through the Central core Theory. Additionally, the relationship between gender-place of residence with the evoked word is explored. Therefore, three hundred and sixty people (from rural and urban areas) were interviewed face to face in two areas in the western region of Mexico. Word association test was carried out, using "whey" as stimulus; the associated words were ordered according to their importance; the polarity index of each associated word was evaluated. The most frequently mentioned words were analyzed based on their frequency of mention and average importance to identify the conceptual structure of the concept representation. The results show and influence of the place of residence on the conceptual structure. Rural participants tend to generate more words with negative connotations, while the central elements of urban consumers are mainly related to dairy products. When comparing consumers by gender, rural and urban women associate "whey" with aspects of both the production process and dairy products. In the case of men, those from the urban zone, relate to aspects related to nutrition, dairy products and nutrients. In contrast, men from the rural area relate whey mainly to negative aspects such as pollution. The study confirms that there is a link between the place of residence and the conformation of the conceptual structure, where the gender-region relationship influences the definition of the term "whey".


Asunto(s)
Productos Lácteos , Suero Lácteo , Masculino , Humanos , Femenino , México , Población Urbana , Proteína de Suero de Leche/química
2.
Carbohydr Polym ; 329: 121739, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38286536

RESUMEN

Carbohydrate-active enzymes from the glycoside hydrolase family 9 (GH9) play a key role in processing lignocellulosic biomass. Although the structural features of some GH9 enzymes are known, the molecular mechanisms that drive their interactions with cellulosic substrates remain unclear. To investigate the molecular mechanisms that the two-domain Bacillus licheniformis BlCel9A enzyme utilizes to depolymerize cellulosic substrates, we used a combination of biochemical assays, X-ray crystallography, small-angle X-ray scattering, and molecular dynamics simulations. The results reveal that BlCel9A breaks down cellulosic substrates, releasing cellobiose and glucose as the major products, but is highly inefficient in cleaving oligosaccharides shorter than cellotetraose. In addition, fungal lytic polysaccharide oxygenase (LPMO) TtLPMO9H enhances depolymerization of crystalline cellulose by BlCel9A, while exhibiting minimal impact on amorphous cellulose. The crystal structures of BlCel9A in both apo form and bound to cellotriose and cellohexaose were elucidated, unveiling the interactions of BlCel9A with the ligands and their contribution to substrate binding and products release. MD simulation analysis reveals that BlCel9A exhibits higher interdomain flexibility under acidic conditions, and SAXS experiments indicate that the enzyme flexibility is induced by pH and/or temperature. Our findings provide new insights into BlCel9A substrate specificity and binding, and synergy with the LPMOs.


Asunto(s)
Celulosa , Glicósido Hidrolasas , Glicósido Hidrolasas/metabolismo , Dispersión del Ángulo Pequeño , Difracción de Rayos X , Celulosa/química , Carbohidratos , Especificidad por Sustrato
3.
J Biomol Struct Dyn ; : 1-19, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37817533

RESUMEN

The genus Mammarenavirus belonging to the family Arenaviridae encompasses pathogenic viral species capable of triggering severe diseases in humans, causing concern for the health system due to the high fatality rate associated with them. Currently, there is a dearth of specific therapies against pathogens of the genus. Natural products isolated from plants have impacted the development of drugs against several diseases. The Núcleo de Bioensaios, Biossíntese e Ecofisiologia de Produtos Naturais (NuBBE) database offers several natural compounds with antimicrobial activities that can be used in the development of new antiviral drugs. In this context, here we modeled the arenavirus L protein, multifunctional machinery essential for the viral replicative cycle, making this enzyme a potential candidate for targeting the development of antivirals against genus pathogens. Using the modeled L protein, a virtual screening was performed, which suggested eleven molecules from the NuBBE database that binds to the active site of the L protein, which was promising in the in silico predictions of absorption and toxicity analysis. The NuBBE 1642 molecule proved to be the best candidate for four of the five species evaluated, acting as a possible broad-spectrum molecule. Additionally, our results showed that the L protein is highly conserved among species of the genus, as well as presenting close phylogenetic relationships between many of the species studied, strengthening its candidacy as a therapeutic target. The data presented here demonstrate that some NuBBE molecules are potential ligands for the L protein of arenaviruses, which may help to contain possible outbreaks.Communicated by Ramaswamy H. Sarma.

4.
Rev. biol. trop ; Rev. biol. trop;70(1)dic. 2022.
Artículo en Inglés | LILACS, SaludCR | ID: biblio-1407242

RESUMEN

Abstract Introduction: Inventories are essential for forest management, but, in the Amazon region, the absence of standardization produces information loss, low accuracy, and inconsistent measurements. This prevents valid comparisons and compromises the use of information in networks and software. Sampling unit size is of key importance in the inventory of native forests, particularly regarding accuracy and costs. Objective: To identify a plot size that provides adequate precision for dendrometric parameters in the Amazon. Methods: In Cotriguaçu, Mato Grosso, Brazil, we tested four plot sizes with six repetitions each: 2 500, 5 000, 7 500, and 10 000 m². We measured diameter at breast height, population density, basal area, and biomass. We applied Shannon and Jaccard indexes; Weibull 2P and Gamma functions to fit the diametric distribution; and the Akaike Information Criterion for the best model. Results: There was a directly proportional relationship between plot area and population similarity, but diversity did not indicate significant alterations. Plot size did not affect dendrometric attributes and diametric distribution. Larger plot areas led to lower coefficients of variation and smaller confidence intervals. The Gamma function was the best model to represent the distributions of different plot sizes. Conclusions: For similar forests, we recommend the 2 500 m² plot to evaluate diameter at breast height, population density, basal area, and biomass.


Resumen Introducción: Los inventarios son fundamentales para la gestión forestal, pero en la Amazonía la ausencia de estandarización produce pérdida de información, baja precisión y mediciones inconsistentes. Esto impide comparaciones válidas y compromete el uso de información en redes y programas. El tamaño de la unidad de muestreo es de importancia clave en el inventario de bosques nativos, particularmente en lo que respecta a la precisión y los costos. Objetivo: Identificar un tamaño de parcela que proporcione una precisión adecuada para los parámetros dendrométricos en la Amazonía. Métodos: En Cotriguaçu, Mato Grosso, Brasil, probamos cuatro tamaños de parcela con seis repeticiones cada una: 2 500, 5 000, 7 500 y 10 000 m². Medimos diámetro a la altura del pecho, densidad de población, área basal y biomasa. Se aplicaron los índices de Shannon y Jaccard; Funciones Weibull 2P y Gamma para adaptarse a la distribución diametral; y el Criterio de Información de Akaike para el mejor modelo. Resultados: Hubo una relación directamente proporcional entre el área de parcela y la similitud poblacional, pero la diversidad no indicó alteraciones significativas. El tamaño de la parcela no afectó los atributos dendrológicos y la distribución diametral. Las áreas de parcela más grandes dieron lugar a coeficientes de variación más bajos e intervalos de confianza más pequeños. La función Gamma fue el mejor modelo para representar las distribuciones de diferentes tamaños de parcela. Conclusiones: Para bosques similares, recomendamos la parcela de 2 500 m² para evaluar diámetro a la altura del pecho, densidad de población, área basal y biomasa.


Asunto(s)
Bosques , Muestreo , Ecosistema Amazónico , Brasil
5.
Int J Mol Sci ; 23(20)2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36293059

RESUMEN

Naegleria fowleri, also known as the "brain-eating" amoeba, is a free-living protozoan that resides in freshwater bodies. This pathogenic amoeba infects humans as a casual event when swimming in contaminated water. Upon inhalation, N. fowleri invades the central nervous system and causes primary amoebic meningoencephalitis (PAM), a rapidly progressive and often fatal disease. Although PAM is considered rare, reducing its case fatality rate compels the search for pathogen-specific proteins with a structure-function relationship that favors their application as targets for discovering new or improved drugs against N. fowleri infections. Herein, we report a computational approach to study the structural features of Nf314 (a serine carboxypeptidase that is a virulence-related protein in N. fowleri infections) and assess its potential as a drug target, using bioinformatics tools and in silico molecular docking experiments. Our findings suggest that Nf314 has a ligand binding site suitable for the structure-based design of specific inhibitors. This study represents a further step toward postulating a reliable therapeutic target to treat PAM with drugs specifically aimed at blocking the pathogen proliferation by inhibiting protein function.


Asunto(s)
Infecciones Protozoarias del Sistema Nervioso Central , Naegleria fowleri , Humanos , Infecciones Protozoarias del Sistema Nervioso Central/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Ligandos , Naegleria fowleri/metabolismo , Agua/metabolismo
6.
Front Immunol ; 13: 931372, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35967415

RESUMEN

COVID-19 brought scenes from sci-fi movies into real life. Infected individuals include asymptomatic cases to severe disease leading to death, suggesting the involvement of the genetic constitution of populations and pathogens contributing to differential individuals' outcomes. To investigate shared immunogenic features between SARS-CoV-2 targets and other coronaviruses, we modeled their peptides in 3D structures of HLA-A*02:01 (pMHC), comparing their molecular surfaces These structures were also compared with a panel of epitopes from unrelated viruses, looking for potential triggers conferring cross-protection in uninfected individuals. As expected, SARS-CoV 1 and 2 peptides share molecular and physicochemical features, providing an explanation for the verified experimental immunogenicity among them. Surprisingly, even discordant sequences from human coronaviruses 229E, OC43 and epitopes from unrelated viruses involved in endemic human infections exhibit similar fingerprints of immunogenicity with SARS-CoV-2 peptides. The same approach indicates a conserved CD8+ T cell recognition between Wuhan SARS-CoV-2 sequences and altered peptides from Variants of Concern. Examination of structural data over epitope sequence analysis here could explain how previous infections may produce a heterologous immunity response in a global scale against emergent diseases such as Covid-19, mitigating its full lethal potential, and paves the way for the development of wide spectrum vaccine development.


Asunto(s)
COVID-19 , SARS-CoV-2 , Antígenos Virales , Epítopos , Humanos , Péptidos
7.
Vaccines (Basel) ; 10(6)2022 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-35746472

RESUMEN

The global scale of the COVID-19 pandemic has demonstrated the evolution of SARS-CoV-2 and the clues of adaptation. After two years and two months since the declaration of the pandemic, several variants have emerged and become fixed in the human population thanks to extrinsic selective pressures but also to the inherent mutational capacity of the virus. Here, we applied a neutral substitution evolution test to the spike (S) protein of Omicron's protein and compared it to the others' variant of concern (VOC) neutral evolution. We carried out comparisons among the interactions between the S proteins from the VOCs (Alpha, Beta, Gamma, Delta and Omicron) and the receptor ACE2. The shared amino acids among all the ACE2 binding S proteins remain constant, indicating that these amino acids are essential for the accurate binding to the receptor. The complexes of the RBD for every variant with the receptor were used to identify the amino acids involved in the protein-protein interaction (PPI). The RBD of Omicron establishes 82 contacts, compared to the 74 of the Wuhan original viral protein. Hence, the mean number of contacts per residue is higher, making the contact thermodynamically more stable. The RBDs of the VOCs are similar in sequence and structure; however, Omicron's RBD presents the largest deviation from the structure by 1.11 Å RMSD, caused by a set of mutations near the glycosylation N343. The chemical properties and structure near the glycosylation N343 of the Omicron S protein are different from the original protein, which provoke reduced recognition by the neutralizing antibodies. Our results hint that selective pressures are induced by mass vaccination throughout the world and by the persistence of recurrent infections in immunosuppressed individuals, who did not eliminate the infection and ended up facilitating the selection of viruses whose characteristics are different from the previous VOCs, less pathogenic but with higher transmissibility.

8.
Heliyon ; 8(4): e09260, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35464708

RESUMEN

The optimization of civil structures is a technique whose purpose is to efficiently use the materials that make up the structural systems based on previously established restrictions and objectives. The use and development of these techniques has been closely linked to technological advance since, through the use of computer equipment, complex mathematical models can be solved with low cost and time. This article presents OPS Design v2.0, a computer tool that allows obtaining a preliminary optimal distribution of metallic structural profiles in a Non-Braced Frame System (OMF: Ordinary Moment Frame). The optimization model implemented in OPS Design v2.0 seeks to minimize the number of different profiles and the structure's own weight in order to reduce the construction complexity and the weight per linear meter (costs in quantities of material). To evaluate its effectiveness, a case study was developed where it was concluded that the designs produced by the application are more efficient than those obtained by commercial tools, thus reducing the computational expense and time used by designers in iterative processes that are carried out in the initial phases project.

9.
Molecules ; 27(8)2022 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-35458600

RESUMEN

An immunoadjuvant preparation (named Fraction B) was obtained from the aqueous extract of Quillaja brasiliensis leaves, and further fractionated by consecutive separations with silica flash MPLC and reverse phase HPLC. Two compounds were isolated, and their structures elucidated using a combination of NMR spectroscopy and mass spectrometry. One of these compounds is a previously undescribed triterpene saponin (Qb1), which is an isomer of QS-21, the unique adjuvant saponin employed in human vaccines. The other compound is a triterpene saponin previously isolated from Quillaja saponaria bark, known as S13. The structure of Qb1 consists of a quillaic acid residue substituted with a ß-d-Galp-(1→2)-[ß-d-Xylp-(1→3)]-ß-d-GlcpA trisaccharide at C3, and a ß-d-Xylp-(1→4)-α-l-Rhap-(1→2)-[α-l-Arap-(1→3)]-ß-d-Fucp moiety at C28. The oligosaccharide at C28 was further substituted at O4 of the fucosyl residue with an acyl group capped with a ß-d-Xylp residue.


Asunto(s)
Saponinas , Triterpenos , Adyuvantes Inmunológicos/química , Humanos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Quillaja/química , Saponinas/química , Triterpenos/química
10.
Pharmaceutics ; 14(2)2022 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-35214026

RESUMEN

Organogels (ORGs) are remarkable matrices due to their versatile chemical composition and straightforward preparation. This study proposes the development of ORGs as dual drug-carrier systems, considering the application of synthetic monoketonic curcuminoid (m-CUR) and lidocaine (LDC) to treat topical inflammatory lesions. The monoketone curcuminoid (m-CUR) was synthesized by using an innovative method via a NbCl5-acid catalysis. ORGs were prepared by associating an aqueous phase composed of Pluronic F127 and LDC hydrochloride with an organic phase comprising isopropyl myristate (IPM), soy lecithin (LEC), and the synthesized m-CUR. Physicochemical characterization was performed to evaluate the influence of the organic phase on the ORGs supramolecular organization, permeation profiles, cytotoxicity, and epidermis structural characteristics. The physico-chemical properties of the ORGs were shown to be strongly dependent on the oil phase constitution. Results revealed that the incorporation of LEC and m-CUR shifted the sol-gel transition temperature, and that the addition of LDC enhanced the rheological G'/G″ ratio to higher values compared to original ORGs. Consequently, highly structured gels lead to gradual and controlled LDC permeation profiles from the ORG formulations. Porcine ear skin epidermis was treated with ORGs and evaluated by infrared spectroscopy (FTIR), where the stratum corneum lipids were shown to transition from a hexagonal to a liquid crystal phase. Quantitative optical coherence tomography (OCT) analysis revealed that LEC and m-CUR additives modify skin structuring. Data from this study pointed ORGs as promising formulations for skin-delivery.

11.
Mol Biotechnol ; 64(4): 388-400, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34655039

RESUMEN

Tannin acyl hydrolases or tannases (E.C.3.1.1.20) are enzymes that hydrolyze the ester bond of tannins to produce gallic acid and glucose. We engineered the Aspergillus niger GH1 tannase sequence and Pichia pastoris strains to produce and secrete the enzyme as a single-chain protein. The recombinant tannase was N-glycosylated, had a molecular mass after N-deglycosylation of 65.4 kDa, and showed activity over broad pH and temperature ranges, with optimum pH and temperature of 5.0 and 20 °C. Furthermore, the single-chain tannase had an 11-fold increased specific activity in comparison to the double-chain A. niger GH1 tannase, which was also produced in P. pastoris. Structural analysis suggested that the high specific activity may be due to the presence of a flexible loop in the lid domain, which can control and drive the substrate to the active site. In contrast, the low specific activity of the double-chain tannase may be due to the presence of a disordered and flexible loop that could hinder the substrate's access to the binding site. Based on its biochemical properties, high specific activity, and the possibility of its production in P. pastoris, the tannase described could be used in food and beverage processing at low and medium temperatures.


Asunto(s)
Aspergillus niger , Proteínas Fúngicas , Hidrolasas de Éster Carboxílico/química , Proteínas Fúngicas/metabolismo , Concentración de Iones de Hidrógeno , Pichia/genética , Pichia/metabolismo , Saccharomycetales
12.
Podium (Pinar Río) ; 16(1): 125-137, tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1155063

RESUMEN

RESUMEN La importancia y transcendencia de cada variable que influye en el entrenamiento de la flexibilidad en gimnastas evaluada por especialistas, podrían modelarse prospectivamente para considerar la toma a mediano y largo plazo de decisiones acertadas y relacionadas con el proceso de dirección del entrenamiento. Conocer las implicaciones y el nivel de importancia de cada variable de interés podría optimizar la preparación deportiva, siendo el análisis estructural una herramienta para lograr dicho fin. El objetivo de este trabajo es determinar variables claves sobre el entrenamiento de la flexibilidad en gimnasia artística masculina; está basado en una investigación prospectiva de análisis cualitativo, aplicando matrices que interrelacionaron diversas variables de importancia, delimitando a futuro cómo modelar un entrenamiento de flexibilidad en gimnasia artística masculina. Se aplicó un cuestionario a 13 de especialistas, estudiando nueve variables, cual indica que la variable más influyente es el nivel de conocimiento de los entrenadores (NCE), y la más dependiente es el modelo de entrenamiento (MoE). Las variables métodos de entrenamiento (ME) y técnicas de entrenamiento (TE) destacan por tener niveles altos de influencia y dependencia, las variables resultantes serían las metodologías observaciones (MO); individualización (I) y modelo de entrenamiento (MoE), y la variable pelotón la edad de entrenamiento (EdE). Se evidencia a criterio de los especialistas el valor supremo del nivel de conocimientos de los entrenadores sobre el desarrollo de la flexibilidad, siendo un condicionante a potenciar mediante cursos de superación, orientando el uso de los mejores métodos y técnicas de entrenamiento para potenciar óptimamente la flexibilidad en la gimnasia artística masculina.


RESUMO A importância e transcendência de cada variável que influencia o treino de flexibilidade em ginastas, avaliada por especialistas, poderia ser modelada prospectivamente para considerar as decisões a médio e longo prazo relacionadas com o processo de gestão do treino. O conhecimento das implicações e do nível de importância de cada variável de interesse poderia optimizar a preparação desportiva, sendo a análise estrutural uma ferramenta para atingir este objetivo. O objetivo deste trabalho é determinar variáveis chave no treino de flexibilidade na ginástica artística masculina; baseia-se numa pesquisa prospectiva de análise qualitativa, aplicando matrizes que inter-relacionam várias variáveis importantes, delimitando no futuro como modelar um treino de flexibilidade na ginástica artística masculina. Foi aplicado um questionário a 13 especialistas, estudando nove variáveis, o que indica que a variável mais influente é o nível de conhecimento dos treinadores (NCE), e a mais dependente é o modelo de formação (MoE). Os variáveis métodos de treino (ME) e técnicas de treino (TE) destacam-se por terem elevados níveis de influência e dependência, as variáveis resultantes seriam as observações metodológicas (MO); individualização (I) e modelo de treino (MoE), e o pelotão de variáveis a idade de treino (EdE). O valor supremo do nível de conhecimento dos treinadores sobre o desenvolvimento da flexibilidade é evidenciado nos critérios dos especialistas, sendo um fator condicionante a ser valorizado através de cursos de aperfeiçoamento, orientando a utilização dos melhores métodos e técnicas de treino para optimizar a flexibilidade na ginástica artística masculina.


ABSTRACT The importance and transcendence of each variable that influences flexibility training in gymnasts, evaluated by specialists, could be modeled prospectively to consider medium and long term decisions related to the training management process. Knowing the implications and level of importance of each variable of interest could optimize sport preparation, being structural analysis a tool to achieve this goal. The objective of this work is to determine key variables on flexibility training in men's artistic gymnastics; it is based on a prospective research of qualitative analysis, applying matrices that interrelated several variables of importance, delimiting in the future how to model a flexibility training in men's artistic gymnastics. A questionnaire was applied to 13 specialists, studying nine variables, which indicates that the most influential variable is the coaches' Level of knowledge (NCE), and the most dependent is the training model (MoE). The variables training methods (ME) and training techniques (TE) stand out for having high levels of influence and dependence, the resulting variables would be the methodologies observations (MO); individualization (I) and training model (MoE), and the platoon variable the training age (EdE). It is evident, according to the specialists, the supreme value of the level of knowledge of the coaches on the development of flexibility, being a conditioning factor to be enhanced through improvement courses, guiding the use of the best training methods and techniques to optimally enhance flexibility in men's artistic gymnastics.

13.
Rev. ciênc. farm. básica apl ; Rev. ciênc. farm. básica apl;42: 1-10, 20210101.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1254105

RESUMEN

Organic inorganic hybrids present several advantages as drug release systems, such as: high flexibility, high mechanical and thermal resistance, transparency, and low water solubility. These hybrids are synthesized through a chemical route named sol-gel that usually uses as solvente tetrahydrofuran (THF). Objetives: To develop film formers from hybrid materials replacing THF with ethanol, a less toxic solvent for skin application and for the environment. Methods: Four polymers were used: two based on polyethylene oxide (PEO) with molecular weight of 500 and 1900 g mol-1 and two based on polypropylene oxide (PPO), with molecular weight of 400 and 2000 g mol-1. The structural analysis was performed by FTIR, 1H-NMR and 29Si-NMR, and the thermal-mechanical analysis by DSC and TG-DTA. Results: The results of the thermo-mechanical analysis revealed that the solvent replacement did not affect the thermal stability and flexibility of the di-ureasil hybrid. Conclusions: Structural characterization confirmed the formation of hybrids both in THF and in ethanol. Therefore, ethanol is an excellent solvent for the synthesis of these hybrid matrices, since it allows obtaining the same material without changing its characteristics, with some advantages, however, over THF. Furthermore, this paper describes the efficiency of ethanol as a solvent, which is environmentally friendly, to replace THF in the physical-chemical characteristics of these filming former materials.

14.
Materials (Basel) ; 15(1)2021 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-35009426

RESUMEN

The performance of an extractor device used in the food industry was studied from the development of structural analysis through computational modeling based on finite elements. These analyses considered the mechanical properties of AISI 304 and 420 stainless steels, in addition to the tribological aspects of the device in operation. Initially, uniaxial tensile tests were carried out according to the ABNT NBR 6892 standard and hardness tests were carried out according to ASTM E384, E92, and E18 standards. From the mechanical tests, structural analyses were carried out numerically on each of the components of the extractor device. After analyzing all the components, the device was assembled to be tested in operation. The wear and service life of devices made from these two materials were evaluated. From this study, it could be concluded that the extractor device made with AISI 420 stainless steel, in addition to having a lower manufacturing cost, suffered less wear and had an increase in service life of up to 650% compared to the extractor device made with steel stainless steel AISI 304.

15.
Antibiotics (Basel) ; 9(9)2020 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-32967114

RESUMEN

Amphibian skin secretions are abundant in bioactive compounds, especially antimicrobial peptides. These molecules are generally cationic and rich in hydrophobic amino acids, have an amphipathic structure and adopt an α-helical conformation when in contact with microorganisms membranes. In this work, we purified and characterized Figainin 1, a novel antimicrobial and antiproliferative peptide from the cutaneous secretion of the frog Boana raniceps. Figainin 1 is a cationic peptide with eighteen amino acid residues-rich in leucine and isoleucine, with an amidated C-terminus-and adopts an α-helical conformation in the presence of trifluoroethanol (TFE). It displayed activity against Gram-negative and especially Gram-positive bacteria, with MIC values ranging from 2 to 16 µM, and showed an IC50 value of 15.9 µM against epimastigote forms of T. cruzi; however, Figanin 1 did not show activity against Candida species. This peptide also showed cytolytic effects against human erythrocytes with an HC50 of 10 µM, in addition to antiproliferative activity against cancer cells and murine fibroblasts, with IC50 values ranging from 10.5 to 13.7 µM. Despite its adverse effects on noncancerous cells, Figainin 1 exhibits interesting properties for the development of new anticancer agents and anti-infective drugs against pathogenic microorganisms.

16.
Artículo en Inglés | MEDLINE | ID: mdl-32673831

RESUMEN

As a special traditional Chinese medicine, Astragalus polysaccharides for injection (APS, batch no. Zhunzi Z20040086) includes complex polysaccharide macromolecules that may increase the risk upon application. Although fingerprints for quality control are available, the specific active ingredients are unclear. Identifying the active components is the key to reduce the risk of adverse reactions of the drug. In this work, APS was mainly separated into two components, namely, macromolecular component (APS-I) and small molecular components (APS-II). The molecular weight measurement revealed that the average molecular weight of APS-I exceeded 500 kDa, and that of APS-II was 10 kDa. Monosaccharide-composition analysis revealed that APS-I consisted of glucose, galactose, arabinose, rhamnose, and galacturonic acid, with a ratio of approximately 1.5:1:5.4:0.08:0.1. Meanwhile, APS-II consisted of glucose, galactose, arabinose, rhamnose, and galacturonic acid, with a molar ratio of 9:1:1.4:0.04:0.001. Methylation, FT-IR, and NMR analysis indicated that the APS-I monosaccharide residue was linked as follows: D-Glcp-(1→, →4)-D-Glcp-(1→, →2)-L-Rhap-(1→, D-Araf-(1→, →5)-D-Araf-(1→, →2,5)-D-Araf-(1→, →4)-D-Galp-(1 â†’ . Meanwhile, the APS-II monosaccharide residue was connected as follows: α-D-Glcp-(1→, →4)-α-D-Glcp-(1→, →6)-α-D-Glcp-(1→, →4,6)-α-D-Glcp-(1→, →3,4,6)-α-D-Glcp-(1→, →2)-α-L-Rhap-(1→, α-D-Araf-(1→, →5)-α-D-Araf-(1→, →4)-ß-D-Galp-(1 â†’ . Screening experiments on their in vitro immunological activity showed that APS-II had stronger effect on innate and adaptive immunities than APS-I. In vivo animal experiments showed that APS-II can increase the leukocyte level of cyclophosphamide immunosuppressed mice and improve their immunomodulatory ability. Therefore, APS-II is the main active ingredient of APS and is expected to become a new generation of APS products.


Asunto(s)
Planta del Astrágalo , Medicamentos Herbarios Chinos , Monosacáridos , Animales , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos/análisis , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Femenino , Factores Inmunológicos/análisis , Factores Inmunológicos/química , Factores Inmunológicos/farmacología , Espectroscopía de Resonancia Magnética , Ratones , Ratones Endogámicos BALB C , Peso Molecular , Monosacáridos/análisis , Monosacáridos/química , Monosacáridos/farmacología , Fagocitosis/efectos de los fármacos , Células RAW 264.7
17.
Biomolecules ; 10(5)2020 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-32443921

RESUMEN

In recent years, the number of new antimicrobial drugs launched on the market has decreased considerably even though there has been an increase in the number of resistant microbial strains. Thus, antimicrobial resistance has become a serious public health problem. Amphibian skin secretions are a rich source of host defense peptides, which generally are cationic and hydrophobic molecules, with a broad-spectrum of activity. In this study, one novel multifunctional defense peptide was isolated from the skin secretion of the Chaco tree frog, Boana raniceps. Figainin 2 (1FLGAILKIGHALAKTVLPMVTNAFKPKQ28) is cationic and hydrophobic, adopts an α-helical structure in 50% (v/v) trifluoroethanol (TFE), and is thermally stable. This peptide exhibited activity against Gram-negative and Gram-positive pathogenic bacteria arboviruses, T. cruzi epimastigotes; however, it did not show activity against yeasts. Figainin 2 also showed antiproliferative activity on cancer cells, is moderately active on human erythrocytes, and activates the oxidative burst in human neutrophils.


Asunto(s)
Proteínas Anfibias/metabolismo , Anuros/metabolismo , Defensinas/metabolismo , Piel/metabolismo , Proteínas Anfibias/química , Proteínas Anfibias/farmacología , Animales , Arbovirus/efectos de los fármacos , Bacterias/efectos de los fármacos , Candida/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Defensinas/química , Defensinas/farmacología , Hemólisis/efectos de los fármacos , Humanos , Neutrófilos/efectos de los fármacos , Conformación Proteica en Hélice alfa , Trypanosoma cruzi/efectos de los fármacos
18.
Bioresour Technol ; 301: 122706, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31945682

RESUMEN

Bioemulsifiers are surface active compounds which could be potentially used in food processing, cosmetic sector and oil recovery. Sugarcane straw (SS), was used as the raw substrate for the production of bio-emulsifiers (BE) by Cutaneotrichosporon mucoides. Three different delignification strategies using dilute sodium hydroxide, sodium sulfite and ammonium hydroxide followed by enzymatic hydrolysis (Cellic CTec 2, 7.5% total solids, 15 FPU/g, 72 h) were studied. Enzyme hydrolysis of ammonium hydroxide pretreated SS showed a maximum of 62.19 ± 0.74 g/l total reducing sugars with 88.35% hydrolytic efficiency (HE) followed by sodium hydroxide (60.06 ± 0.33 g/l; 85.40% HE) and sodium sulfite pretreated SS (57.22 ± 0.52 g/l; 84.71% HE), respectively. The ultrastructure of SS (native and delignified) by fourier transform-infrared and near infrared spectroscopy, revealed notable structural differences. The fermentation of hydrolysates by C. mucoides into bioemulsifiers showing emulsification index (EI) of 54.33%, 48.66% and 32.66% from sodium sulfite, sodium hydroxide, and ammonium hydroxide pretreated SS, respectively.


Asunto(s)
Saccharum , Trichosporon , Hidróxido de Amonio , Fermentación , Hidrólisis , Hidróxido de Sodio
19.
Endocrine ; 68(1): 241-247, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31902113

RESUMEN

PURPOSE: Among the inheritable forms of impaired sensitivity to thyroid hormone, resistance to thyroid hormone (RTH) due to mutations in the thyroid hormone receptor beta gene (THRB) is the first and best known described defect, revealing a wide phenotypic variability with an incompletely understood physiopathology. The objective of this study was to evaluate two novel mutations in THRB, N331H and L346R, in an attempt to provide a rational understanding of the harmful effects caused by them. METHODS: The mutations of two patients with RTHß were reproduced for analysis of gene transactivation by dual-luciferase reporter assay, and for molecular modeling for crystallography-based structural assessment. Serum measurements of TSH and FT4 were performed to compare the thyrotrophic resistance to thyroid hormone between RTHß patients and controls. RESULTS: Both mutants showed impaired gene transactivation, with greater damage in L346R. Molecular modeling suggested that the damage occurring in N331H is primarily due to reduced strength of the hydrogen bonds that stabilize T3 in its ligand-binding cavity (LBC), whereas in L346R, the damage is more marked and is mainly due to changes in hydrophobicity and molecular volume inside the LBC. Hormonal dosages indicated that the L346R mutant exhibited greater thyrotrophic resistance than N331H. CONCLUSIONS: This study provides a rational understanding of the effects of mutations, indicating deleterious structural changes in the LBC in both THR, and discloses that not only the position of the mutation but, notably, the nature of the amino acid exchange, has a cardinal role in the functional damage of the receptor.


Asunto(s)
Receptores beta de Hormona Tiroidea , Síndrome de Resistencia a Hormonas Tiroideas , Humanos , Mutación , Receptores beta de Hormona Tiroidea/genética , Síndrome de Resistencia a Hormonas Tiroideas/genética , Hormonas Tiroideas
20.
Movimento (Porto Alegre) ; 26: e26038, 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1356518

RESUMEN

Abstract: This manuscript addresses the internal logic of sparring taekwondo, regulated by the World Taekwondo Federation, to explain motor actions used in competitions. A narrative review was conducted on Google Scholar, Scopus, Web of Science, Ebsco, PubMed, ProQuest, and Dialnet databases, guided by structural and functional taekwondo parameters with no limits as to year of publication or language used. The authors describe the various elements that make up the sport's internal logic such as regulation, space, time, motor communication, roles and sub-roles in addition to the techniques or execution models that explain their special characteristics. This could assist in further examining the characteristics of that sport, defining combat actions, and contextualizing the real competitive situation by adapting tactical taekwondo sequences. Being aware of this sport's unique characteristics will enable creating the necessary framework to continue research on Olympic-level taekwondo.


Resumo: O objetivo do manuscrito é abordar a lógica interna do taekwondo competição regulamentada pela Federação Mundial do Taekwondo para explicar a ação motora na competição. Uma revisão narrativa foi realizada com base nos parâmetros estruturais e funcionais do taekwondo nos bancos de dados do Google Scholar, Scopus, Web of Science, Ebsco, PubMed, ProQuest e Dialnet, sem limitar o ano de publicação nem o idioma utilizado. Os autores se referem aos diversos elementos que compõem a lógica interna mencionada, como regulação, espaço, tempo, comunicação motora, papéis e subfunções, além dos modelos de técnica ou execução, explicando suas particularidades. Isso poderia nos ajudar a aprofundar as características desse esporte, definir a ação de combate e contextualizar a situação real da competição, adaptando as sequências táticas do taekwondo. O conhecimento das particularidades desse esporte permite criar uma estrutura necessária para continuar o trabalho da pesquisa no taekwondo olímpico .


Resumen: El objetivo de este manuscrito es abordar la lógica interna del taekwondo de competición regulado por la Federación Mundial de Taekwondo para explicar la acción motriz en la competición. Se realizó una revisión narrativa basada en los parámetros estructurales y funcionales del taekwondo en las bases de datos del Google Scholar, Scopus, Web of Science, Ebsco, PubMed, ProQuest y Dialnet sin limitar el año de publicación ni el idioma. Los autores se refieren a los diversos elementos que componen la lógica interna mencionada, como reglamento, espacio, tiempo, comunicación motriz, roles y subfunciones, además de los modelos de técnica o ejecución, explicando sus particularidades. Esto podría ayudarnos a profundizar en las características del taekwondo, a definir la acción de combate y a contextualizar la situación real de la competición, adaptando las secuencias tácticas del taekwondo. El conocimiento de las particularidades de este deporte permite crear un marco necesario para continuar el trabajo de investigación en el taekwondo olímpico.


Asunto(s)
Deportes , Artes Marciales , Métodos
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