Testing for the ability to modify antibiotics of Panus tigrinus 8/18 Lentinus strigosus 1566 laccase / Teste de capacidade para modificar antibióticos a partir da lacase de Panus tigrinus 8/18 e Lentinus strigosus 1566

In advanced biotechnology, the utilization of enzymes to achieve new or modified compounds with antibacterial, fungicidal, and anti-cancer specifications is crucial. Mushroom lactases are a hopeful biocatalyst for the synthesis and modification of different compounds. They are an accessible and inexpensive enzyme for the preparation of reaction objects and have recently received attention. Laccase purification was performed from basidiomycete Lentinus strigosus (LS) in several stages: Stage 1. On ion-exchange chromatography on TEAE Servacell 23 (400 ml), two distinctly separated laccase activity peaks were observed, eluted from the carrier at 0.21 and 0.27 M NaCl. In order to reduce the loss of enzymes, all fractions with laccase activity were collected, concentrated, and desalted using an ultrafiltration cell (Amicon, United States) with a UM-10 membrane. Stage 2. The resulting preparation with laccase activity was applied to a Q-Sepharose column (60 ml). Two well-separated peaks with laccase activity were obtained during the elution: laccase I (0.12 M NaCl) and laccase II (0.2 M NaCl). Stage 3. In the course of further purification of both enzymes, carried out on anion-exchange carrier Resource Q (6 ml), a broken gradient was used: 0 - 10%, 10 - 20%, and 20 - 100% with 1M NaCl. Stage 4. Both laccase I and laccase II, obtained after Resource Q, were desalted, concentrated to 1 ml each, and applied to a Superdex 75 gel filtration column. As a result, two laccases were obtained in a homogeneous form.

Na biotecnologia moderna, o uso de enzimas para obter compostos novos ou modificados com propriedades antibacterianas, antifúngicas e anticancerígenas é crucial. Lactases de cogumelos são biocatalisadores promissores para síntese e modificação de diferentes compostos, por serem enzimas baratas e disponíveis para a preparação de componentes de reação, e vem recebendo a devida atenção recentemente. A purificação da lacase foi realizada a partir do basidiomiceto Lentinus strigosus em vários estágios: Etapa 1 - na cromatografia de troca iônica em TEAE Servacell 23 (400 ml), foram observados dois picos de atividade da lacase distintamente separados, com eluição do transportador a 0,21 e 0,27 M de NaCl. Para reduzir a perda de enzimas, todas as frações com atividade de lacase foram coletadas, concentradas e dessalinizadas em uma célula de ultrafiltração (Amicon, Estados Unidos) com membrana UM-10; Etapa 2 - a preparação resultante com atividade de lacase foi aplicada a uma coluna Q-Sepharose (60 ml). Durante a eluição, foram obtidos dois picos bem separados com atividade de lacase: lacase I (NaCl 0,12 M) e lacase II (NaCl 0,2 M); Etapa 3 - no decurso da purificação adicional de ambas as enzimas, realizada no Recurso Q de transportador de troca aniônica (6 ml), um gradiente quebrado foi usado: 0-10%, 10-20% e 20-100% com NaCl 1M; Etapa 4 - tanto a lacase I como a lacase II, obtidas após o Recurso Q, foram dessalinizadas e concentradas para 1 ml cada e aplicadas a uma coluna de filtração em gel Superdex 75. Como resultado, duas lacases foram obtidas de forma homogênea.

Pattern of liver enzymes and maternal outcome in eclamptic patients admitted to the Intensive Care Unit, University College Hospital, Nigeria

Introduction: Eclampsia, a hypertensive disorder, is one of the leading causes of maternal mortality in developing countries like Nigeria. We evaluated the relationship between the pattern of liver enzymes and maternal mortality in eclamptic women. Method: A retrospective study of 55 eclamptic women admitted to the Intensive Care Unit (ICU), University College Hospital, Nigeria, was conducted. Data were obtained on their demographic, obstetric, and clinical characteristics, liver enzyme patterns, and maternal outcome. Analysis was by descriptive statistics, univariate analysis, and non-parametric tests with level of significance set at p<0.05. Results: Maternal deaths occurred in 27.3% and elevation of liver enzymes was observed more among the dead patients compared with those who survived. Alanine aminotransferase (ALT) was the most commonly elevated liver enzyme, occurring in almost all (90.9%) the patients. Maternal mortality was significantly associated with age (p=0.001), saturated oxygen levels (p=0.007), elevated alkaline phosphatase (p=0.008), alanine aminotransferase (p=0.013), aspartate aminotransferase (p=0.016), and total bilirubin (p<0.001). Conclusion: Maternal mortality due to eclampsia was clinically associated with age, elevated liver enzymes and a lower serum level of total bilirubin. Liver transaminases are therefore important prognostic indicators associated with eclampsia.

Shading minimizes the effects of water deficit in Campomanesia xanthocarpa (Mart) O Berg seedlings / Sombreamento minimiza o efeito do déficit hídrico em mudas de Campomanesia xanthocarpa (Mart) O Berg

The objective of this study was to evaluate the activity of antioxidant enzymes, the functioning of the photosystem II and quality of C. xanthocarpa seedlings cultivated under intermittent water deficit and shading levels and the influence of shading on recovery potential after suspension of the stress conditions. The seedlings were subjected to three levels of shading (0, 30, and 70%), six periods of evaluation (start: 0 days; 1st and 2nd photosynthesis zero: 1st and 2nd P0; 1st and 2nd recovery: 1stand 2nd REC; and END), and two forms of irrigation (control: periodically irrigated to maintain 70% substrate water retention capacity, and intermittent irrigation: suspension of irrigation). The plants subjected to intermittent irrigation conditions at 0% shading showed a reduction in water potential (Ψw) and potential quantum efficiency of photosystem II (Fv/Fm) and maximum efficiency of the photochemical process (Fv/F0) and an increase in basal quantum production of the non-photochemical processes (F0/Fm). Superoxide dismutase (SOD) activity was higher in the leaves than in the roots. The C. xanthocarpa is a species sensitive to water deficit but presents strategies to adapt to an environment under temporary water restriction, which are more temporary are most efficient under shading. The seedlings with water deficit at all levels of shading exhibited higher protective antioxidant activity and lower quality at 0% shading. The shading minimizes prevents permanent damage to the photosystem II and after the re-irrigation, the evaluated characteristics showed recovery with respect to the control group, except POD and SOD activities in the leaves.

O objetivo deste estudo foi avaliar a atividade de enzimas antioxidantes, o funcionamento do fotossistema II e a qualidade de mudas de C. xanthocarpa cultivadas sob déficit hídrico intermitente e níveis de sombreamento e a influência do sombreamento sobre o potencial de recuperação após suspensão das condições de estresse. As mudas foram submetidas a três níveis de sombreamento (0, 30 e 70%), seis períodos de avaliação (início: 0 dias; 1ª e 2ª fotossíntese zero: 1ª e 2ª P0; 1ª e 2ª recuperação: 1ª e 2ª REC; e final), e duas formas de irrigação (controle: periodicamente irrigado para manter 70% da capacidade de retenção de água do substrato, e irrigação intermitente: suspensão da irrigação). As plantas submetidas às condições de irrigação intermitente a 0% de sombreamento apresentaram redução do potencial hídrico (Ψw) e eficiência quântica potencial do fotossistema II (Fv/Fm) e máxima eficiência do processo fotoquímico (Fv/F0) e aumento da produção quantica basal dos processos não fotoquímicos (F0/Fm). A atividade da superóxido dismutase (SOD) foi maior nas folhas do que nas raízes. C. xanthocarpa é uma espécie sensível ao déficit hídrico, mas apresenta estratégias para se adaptar a um ambiente com restrição hídrica temporária, sendo mais eficientes sob sombreamento. As mudas com déficit hídrico em todos os níveis de sombreamento exibiram maior atividade antioxidante protetora e menor qualidade no sombreamento 0%. O sombreamento minimiza danos permanentes ao fotossistema II e após a re-irrigação, as características avaliadas apresentaram recuperação em relação ao grupo controle, exceto atividades de POD e SOD nas folhas.

Ligninolytic enzymes profiling in association with the aggressiveness of Ganoderma boninense isolates

Aims@#This study was designed to examine the enzyme activity of selected virulent isolates of Ganoderma boninense against oil palm. In a separate in vitro assessment, the effect of macronutrients on the mycelial growth of four selected Ganoderma spp. was also tested.@*Methodology and results@#The study involved a comparison of ligninolytic enzymes; lignin peroxidase (LiP), manganese peroxidase (MnP) and laccase (Lac) profiling of eight isolates of G. boninense, categorized into three levels of aggressiveness, with two control isolates (G. boninense PER71 and G. tornatum NPG1) using solid-state fermentation (SSF). The Principal Component Analysis (PCA) revealed that the isolates had a significant production of ligninolytic enzymes on day 80. The most aggressive isolate, ET61 had the highest Lac production. As for the macronutrient test, mycelial growth for all the Ganoderma spp. was highly affected by potassium (K).@*Conclusion, significance and impact of study@#The findings of this study elucidated the characteristics of G. boninense in relation to enzyme production for the degradation of oil palm lignin and the identification of essential nutrients involved in the survival and growth of Ganoderma spp. The study provides vital information on the pathogenic characteristics of G. boninense isolates involved in biomass degradation along with the role of nutrient on the growth of Ganoderma spp. that may influence basal stem rot (BSR) management in the field.

Study of the interactions of di- and tri-terpenes from Stillingia loranthacea with the enzyme NSP16-NSP10 of SARS-CoV-2 / Estudo das interações de di- e tri-terpenos de Stillingia loranthacea com a enzima NSP16-NSP10 de SARS-CoV-2

Objective: This study aimed to evaluate the interactions of di- and tri-terpenes from Stillingia loranthacea with the enzyme NSP16-NSP10 of SARS-CoV-2, important for viral replication. Methods: The molecular docking technique was used to evaluate this interaction. Results: The analysis showed that the evaluated compounds obtained RMSD values of 0.888 to 1.944 Å and free energy of -6.1 to -9.4 kcal/mol, with the observation of hydrogen bonds, salt bridges, and pi-sulfur, pi-alkyl, and hydrophobic interactions. Conclusion: Thus, the results obtained show the potential of the compounds analyzed against the selected target. Since computer simulations are only an initial step in projects for the development of antiviral drugs, this study provides important data for future research.

Objetivo: avaliar as interações de di- e tri-terpenos de Stillingia loranthacea com a enzima NSP16-NSP10 de SARS-CoV-2, importante para a replicação viral. Métodos: A técnica de docking molecular foi utilizada para avaliar essa interação. Resultados: A análise mostrou que os compostos avaliados obtiveram valores de RMSD de 0,888 a 1,944 Å e energia livre de -6,1 a -9,4 kcal/mol, observando-se ligações de hidrogênio, pontes salinas e pi-enxofre, pi-alquil, e interações hidrofóbicas. Conclusão: Assim, os resultados obtidos mostram o potencial dos compostos analisados frente ao alvo selecionado. Como as simulações computacionais são apenas um passo inicial nos projetos de desenvolvimento de medicamentos antivirais, este estudo fornece dados importantes para pesquisas futuras.

Comparação do efeito de beta alanina, bicarbonato de sódio e limão como agentes tamponantes entre ciclistas em exercício de alta intensidade / Comparison of the effect of beta alanine, sodium bicarbonate and lemon as tamponant agents among high-intensity exercise cyclists

Alguns suplementos exercem atividade tamponante e têm sido reconhecidos por sua contribuição anaeróbica em exercícios de alta intensidade, retardando a fadiga muscular periférica e potencializando assim a performance esportiva. O objetivo deste estudo foi comparar o benefício ergogênico no tamponamento e dano muscular, dos suplementos beta alanina, bicarbonato de sódio e suco de limão por meio da dosagem de lactato sanguíneo e creatinofosfoquinase (CPK) e na performance de ciclistas submetidos a exercício anaeróbico de alta intensidade. Estudo transversal crossover, realizado em quatro etapas, com ciclistas do sexo masculino. A suplementação foi constituída de 6 g de beta alanina, 0,2 g/kg de bicarbonato de sódio e 30 mL de suco de limão. Lactato sanguíneo e enzima CPK foram dosados pelo método teste ultravioleta enzimático e cinético, respectivamente, em cada uma das etapas. A performance correspondeu à rotação máxima por minuto (RPM) da Air Bike. Participaram do estudo sete ciclistas, com média de idade de 31,14 ± 3,71 anos. O lactato e a CPK apresentaram significância entre os momentos em todas as etapas avaliadas, porém as suplementações comparadas entre si não apresentaram diferença estatística. Não houve melhora da performance (p>0,05) com as utilizações de bicarbonato de sódio, beta alanina e suco de limão em ciclistas. Para os parâmetros avaliados, nenhum dos suplementos apresentou superioridade nas variáveis de tamponamento, dano muscular e performance no treinamento.

Some supplements exert buffering activity and have been recognized for their anaerobic contribution to high-intensity exercise, delaying peripheral muscle fatigue and thus enhancing sports performance. The aim of this study was to compare the ergogenic benefit in muscle buffering and damage of beta alanine, sodium bicarbonate and lemon juice supplements through the measurement of blood lactate and creatine phosphokinase (CPK) and on the performance of cyclists submitted to high intensity anaerobic exercise. Cross-sectional study, carried out in 4 stages, with male cyclists. Supplementation was 6 g beta alanine, 0.2 g/kg of sodium bicarbonate and 30 mL of lemon juice. Blood lactate and creatine phosphokinase enzyme were measured by the enzymatic and kinetic ultraviolet test method, respectively, in each of the steps. Performance corresponded to the maximum rotation per minute (RPM) of the Air Bike. Seven cyclists participated in the study, with a mean age of 31.14 ± 3.71 years. Lactate and CPK presented significance between the moments in all the evaluated stages, however the supplements compared to each other showed no statistical difference. There was no performance improvement (p>0.05) with the use of sodium bicarbonate, beta alanine and lemon juice in cyclists. For the parameters evaluated, none of the supplements showed superiority in the variables of buffering, muscle damage and training performance.

Estudio genómico de la Quinua (Chenopodium quinoa Willd): técnicas de secuenciación e identificación genómica. Una revision. / Genomic study of Quinoa (Chenopodium quinoa Willd): sequencing techniques and genomic identification. A review.

INTRODUCCIÓN. La quinua (Chenopodium quinoa Willd), es considerado uno de los alimentos más completos debido a su alto contenido en ácidos grasos, oligoelementos y proteínas ricas en aminoácidos esenciales; sin embargo, también posee metabolitos con propiedades anti nutricionales (saponinas) que deben ser eliminados antes de su consumo. Algunos estudios realizados en el genoma de la quinua, se han basado en la identificación de genes involucrados en la producción de saponinas para inhibir su expresión y evitar los tratamientos de pos cosecha (escarificado). OBJETIVO. Establecer, mediante revisión bibliográfica, las técnicas de biología molecular aplicadas a la expresión genómica de saponinas en quinua (Chenopodium quinoa Willd) MÉTODOS. La revisión bibliográfica, se realizó tomando en cuenta varias fuentes de información, entre ellas: tesis doctorales, artículos científicos, libros y algunas plataformas WEB (www.bbc.com, www.fao.org, www.sidalc.net y https://biología.laguía2000.com) con principal interés en: genoma de la quinua, técnicas de secuenciación, genes identificados y su posterior expresión génica. CONCLUSIONES. El descubrimiento del genoma completo de la quinua en el año 2017, aplicando la técnica SMTR u otras técnicas como la pirosecuenciación, fue el punto de partida para el estudio de genes que le proporciona su adaptabilidad a varias condiciones bióticas y abióticas. De esta manera, en relación a los factores abióticos, se documentó en dos oportunidades que la expresión génica de saponinas, estaba relacionada con genes del citocromo P450 y enzimas como las glucosil transferasas. Ahora bien, aunque los genes involucrados en la respuesta a los agentes bióticos aún no están identificados, este se mantiene como hipótesis relacionándose con el contenido de saponinas.

INTRODUCTION. Quinoa (Chenopodium quinoa Willd), is considered one of the most complete foods due to its high content of fatty acids, trace elements and proteins rich in essential amino acids; however, it also has metabolites with anti-nutritional properties (saponins) that must be eliminated before consumption. Some studies carried out on the quinoa genome have been based on the identification of genes involved in the production of saponins to inhibit their expression and avoid post-harvest treatments (scarification). OBJECTIVE. To establish, through bibliographic review, the molecular biology techniques applied to the genomic expression of saponins in quinoa (Chenopodium quinoa Willd). METHODS. The bibliographic review was carried out taking into account several sources of information, among them: doctoral theses, scientific articles, books and some WEB platforms (www.bbc.com, www.fao.org, www.sidalc.net and https://biología.laguía2000.com) with main interest in: quinoa genome, sequencing techniques, identified genes and their subsequent gene expression. CONCLUSIONS. The discovery of the complete genome of quinoa in 2017, applying the SMTR technique or other techniques such as pyrosequencing, was the starting point for the study of genes that provide its adaptability to various biotic and abiotic conditions. Thus, in relation to abiotic factors, it was reported on two occasions that the gene expression of saponins was related to cytochrome P450 genes and enzymes such as glucosyl transferases. Although the genes involved in the response to biotic agents have not yet been identified, this remains a hypothesis related to the content of saponins.

The role of enzymes in the angiogenic activity of Hancornia speciosa latex

The Hancornia speciosa latex has shown angiogenic activity. Angiogenesis plays a major role in wound healing, and materials that stimulate this process could be used to develop drugs. This study aimed to explain the role of proteins in the H. speciosa serum fraction latex in angiogenesis. Hence, this material was treated with proteinase K and the proteins were inactivated. After protein inactivation, angiogenic activity was assessed with the chick chorioallantoic membrane assay. The result showed that the proteins in the serum fraction are responsible for angiogenic activity. Then, the total protein content in the serum fraction and its enzymatic activity were investigated. The low protein content observed in the H. speciosa serum fraction latex suggests that this biomaterial could be used to develop new drugs with a hypoallergenic response. Despite the low protein content, there was a significant enzymatic activity of at least three enzymes in the serum fraction latex: ß-1,3 glucanase, ß-glucosidase, and proteases. These enzymes seem to influence the healing process, assisting debridement, extracellular matrix remodeling, and collagen deposition, and decreasing the chances of contamination by microorganisms. In conclusion, the enzymes in the H. speciosa serum latex are associated with the angiogenic activity of this biomaterial and may be used to assist the wound healing process.

Achyrocline satureioides (Lam) DC extracts acting as enzyme modulators: digestion, inflammation, and hemostasis / Extratos de Achyrocline satureioides (Lam) DC atuando como moduladores enzimáticos: digestão, inflamação e hemostasia

Achyrocline satureioides is popularly known for its richness in phenolic compounds and medicinal properties (anti-inflammatory, analgesic, and hepatoprotective). The present study aimed at broadening the knowledge about the pharmacological potential exerted by the aqueous and ethanolic extracts of A. satureioides. These extracts were characterized by HPLC and tested for their modulatory action on phospholipases A2 and proteases of snake venoms. In addition, they were tested on the activities of digestive enzymes. Snake venoms were used as tools since they have enzymes with high functional and structural homology to human enzymes. The results demonstrate that the extracts of A. satureioides act as enzymatic inhibitors or potentiators, interfering in processes related to the hemostasis, such as coagulation and thrombus dissolution. In addition, the anti-genotoxic activity and inhibitions exerted on digestive enzymes suggests their potential use in the prevention and/or treatment of several pathologies. New studies could provide information on how the compounds present in the extracts and the different enzymes interact.

A Achyrocline satureioides é popularmente conhecida por sua riqueza em compostos fenólicos e por suas propriedades medicinais (anti-inflamatória, analgésica e hepatoprotetora). No presente estudo, com o objetivo de ampliar o conhecimento sobre o potencial farmacológico exercido por esses extratos, os extratos aquoso e etanólico de A. satureioides foram caracterizados por HPLC e testados quanto à sua ação modulatória sobre as fosfolipases A2 e proteases de peçonhas de serpentes. Além disso, também foram testados em atividades de enzimas digestivas. As peçonhas de serpentes foram usadas como ferramentas por apresentarem enzimas com alta homologia funcional e estrutural às humanas. Os resultados demonstram que os extratos de A. satureioides atuam como inibidores ou potencializadores enzimáticos, interferindo em processos relacionados à hemostasia, como coagulação e dissolução do trombo. Além do mais, destacam seu potencial antigenotóxico e as inibições exercidas sobre as enzimas digestivas direcionando seu potencial de uso na prevenção e/ou tratamento de diversas patologias. Novos estudos poderão fornecer informações sobre os mecanismos de interação entre os compostos presentes nos extratos e as diferentes enzimas.

Cadmium and Mercury Exposure: Oxidative, Neurobehavioural and Histological Alterations to the Cerebellum of Wistar Rats

Background: The unprecedented increase in metal exposure has been aided by modern industrialization and anthropogenic activities. Cadmium and mercury are recognized as two of the most common heavy metals with destructive impacts on most organ systems. The present study was designed to investigate and improve existing literature on the possible deleterious effects of cadmium and mercury exposure. Methods: Adult Wistar rats were treated with cadmium chloride (5 mg/kg/day) and mercury chloride (4 mg/kg/day) for 14 days. Body, brain and cerebellar weights, motor deficits, antioxidant and lipid peroxidation activities as well as histological alterations to the cerebellum were evaluated at the end of the experiment. Results: Findings showed a significant reduction in body and brain weights, dysregulation of antioxidant enzymes activity and impaired locomotion and exploratory activity in treated rats. Also, an increase in lipid peroxidation and degeneration of Purkinje cells of the cerebellum was observed in treated rats. Conclusion: Overall, these results corroborate previous findings that cadmium and mercury induce deleterious effects on the cerebellum and central nervous system. In addition, this study helps to provide an anatomical perspective and information on the exact cerebellar changes induced by cadmium and mercury in Wistar rats.

Green synthesis of gold nanaoparticles using Delphinium Chitralense tuber extracts, their characterization and enzyme inhibitory potential / Síntese verde de nanaopartículas de ouro utilizando extratos de tubérculos Delphinium chitralense, sua caracterização e potencial inibitório enzimático

Greeen synthesis has been introduced as an alternative to chemical synthesis due to the serious consequences. Metal nanoparticles synthesized through green approach have different pharmaceutical, medical and agricultural applications. The present study followed a green and simple route for the preparation of potentially bioactive gold nanoparticles (Au NPs). Au NPs were prepared via green synthesis approach using crude basic alkaloidal portion of the tuber of Delphinium chitralense. The green synthesized Au NPs were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) fourier transform infrared (FTIR), and UV-Visible spectrophotometer. Morphological analysis shows that Au NPs have cubic geometry with different sizes. UV-Vis spectroscopic analysis confirmed the synthesis of Au NPs while XRD proved their pure crystalline phase. The Au NPs showed promising dose dependent inhibition of both AChE and BChE as compared to the crude as well as standard drug.

A síntese verde foi introduzida como uma alternativa à síntese química devido às graves consequências. As nanopartículas metálicas sintetizadas através da abordagem verde têm diferentes aplicações farmacêuticas, médicas e agrícolas. O presente estudo seguiu uma rota verde e simples para a preparação de nanopartículas de ouro potencialmente bioativas (Au NPs). As NPs de Au foram preparadas via abordagem de síntese verde usando a porção alcaloide básica bruta do tubérculo de Delphinium chitralense. As NPs de Au sintetizadas verdes foram caracterizadas por microscopia eletrônica de transmissão (TEM), microscopia eletrônica de varredura (MEV), difração de raios X (DRX), infravermelho com transformada de Fourier (FTIR) e espectrofotômetro UV-Visível. A análise morfológica mostra que as NPs de Au possuem geometria cúbica com tamanhos diferentes. A análise espectroscópica UV-Vis confirmou a síntese de Au NPs enquanto a XRD provou sua fase cristalina pura. O Au NPs mostrou inibição dependente da dose promissora de AChE e BChE em comparação com a droga bruta e padrão.

Direct Synthesis of Bienzyme-like Carbide-derived Carbons via Mild Electrochemical Oxidation of Ti 3AlC 2 MAX / 生物医学与环境科学（英文）

Objective@#To develop effective alternatives to natural enzymes, it is crucial to develop nanozymes that are economical, resource efficient, and environmentally conscious. Carbon nanomaterials that have enzyme-like activities have been extensively developed as substitutes for traditional enzymes.@*Methods@#Carbide-derived carbons (CDCs) were directly synthesized via a one-step electrochemical method from a MAX precursor using an ammonium bifluoride electrolyte at ambient conditions. The CDCs were characterized by systematic techniques.@*Results@#CDCs showed bienzyme-like activities similar to that of peroxidase and superoxide dismutase. We systematically studied the dependence of CDC enzyme-like activity on different electrolytes and electrolysis times to confirm activity dependence on CDC content. Additionally, the synthesis mechanism and CDC applicability were elaborated and demonstrated, respectively.@*Conclusion@#The demonstrated synthesis strategy eliminates tedious intercalation and delamination centrifugation steps and avoids using high concentrations of HF, high temperatures, and halogen gases. This study paves the way for designing two-dimensional material-based nanocatalysts for nanoenzyme and other applications.

Hepatoprotective and antioxidant effects of alcesefoliside from Astragalus monspessulanus

Abstract The hepatoprotective potential of alcesefoliside (AF) from Astragalus monspessulanus was investigated. Iron sulphate/ascorbic acid (Fe2+/AA) lipid peroxidation was induced in rat liver microsomes and pre-incubated with AF and silybin (100, 10 and 1 µmol). Pronounced effects were observed in 100 µmol. In vivo experiments were carried out on rats, challenged orally with carbon tetrachloride (CCl4) alone and after pre-treatment and followed by curative treatment with AF (10 mg/kg). The activity of the serum and antioxidant enzymes, together with reduced glutathione (GSH) levels and malonedialdehyde (MDA) quantity were measured. Microsomal incubation with Fe2+/AA increased MDA production. The pre-incubation with AF reduced the formation of MDA, comparable to silybin. These findings were supported by the in vivo study where CCl4-induced liver damage was discerned by significant increase in serum enzymes and in MDA production as well as by GSH depletion and reduced antioxidant enzymes activity. The AF pre-treatment and consecutive curative treatment normalizes the activity of the serum and antioxidant enzymes alike, as well as the levels of GSH and MDA. Histological examination of AF-treated livers showed a decrease in the abnormal accumulation of lipids in hepatocytes as well as reduced alterative changes in their structure in a model of CCl4-induced toxicity.

Reacciones de hipersensibilidad a alglucosidasa alfa en enfermedad de Pompe: dos casos de desensibilización exitosa / Hypersensitivity reactions to alglucosidase alfa in Pompe disease: two cases of successful desensitization

La enfermedad de Pompe es un desorden neuromuscular autosómico recesivo de baja prevalencia, causado por la deficiencia total o parcial de la enzima alfa glucosidasa ácida (GAA), cuya única terapia de reemplazo enzimático disponible es la alglucosidasa alfa recombinante. Las reacciones adversas asociadas a la infusión se presentan con frecuencia. Se reportan dos casos de desensibilización exitosa con alglucosidasa alfa utilizando protocolos con dosis meta de 20 mg/kg, administrados quincenalmente; el primero de ellos, en una niña con historia de reacción adversa grave a los 15 meses de edad, en quien se utilizó un esquema con una dilución inicial de 1/10.000.000 de 28 pasos y una duración total de 13,1 horas. En el segundo caso, la paciente tuvo una reacción adversa grave a los 4 años de edad, se utilizó el protocolo de 22 pasos, concentración inicial de 1/1.000.000 y duración total de 7,2 horas. Se concluye que en pacientes con enfermedad de Pompe que presentan reacciones adversas durante la terapia de reemplazo enzimático, es posible realizar la desensibilización cada dos semanas con la dosis estándar de 20 mg/kg de forma exitosa, y progresivamente lograr la administración usual de la infusión

Pompe disease is a low prevalence autosomal recessive neuromuscular disorder, caused by total or partial deficiency of the acid alpha-glucosidase (GAA) enzyme, and its only available enzyme replacement therapy is the recombinant alglucosidase alfa. Infusion-associated adverse reactions occur frequently. Two cases of successful desensitization with alglucosidase alfa using protocols with a target dose of 20 mg/kg administered biweekly are reported; the first was a girl who had a history of serious adverse reaction at the age of 15 months, and undergone to a scheme with an initial dilution of 1/10,000,000 with 28 steps and a total duration of 13.1 hours. In the second case, the patient had a severe adverse reaction at the age of 4 years, a 22-step protocol was used with an initial concentration of 1/1,000,000 and a total duration of 7.2 hours. In conclusion, in patients with Pompe disease who presented adverse reactions during enzyme replacement therapy with alglucosidase alfa, it is possible to perform desensitization every two weeks with the standard dose of 20 mg/kg, and progressively achieve the usual administration of the infusion

Current status of whitening agents and enzymes in Dentistry

Abstract This study reviews the knowledge on the use of conventional dental whitening and the use of enzymes as a new approach in bleaching. A review of the literature was based on academic articles and on patents related to the use of enzymes in dental bleaching. Tooth whitening techniques used nowadays are well reported in the literature, and its mechanism of action consists of an oxidoreduction reaction with the release of free radicals. The great instability of radicals, when in contact with the tissues, promotes oxidation and reduction in the size of the pigment chains incorporated into them. These pigments are eventually broken down into smaller and smaller molecular chains and end up being diffused from the dental structure. In turn, the use of enzymes aimed at tooth whitening can be a less harmful alternative to the tooth because their specificity regarding the substrate makes them of great interest to perform specific reactions, reducing collateral effects. The use of proteolytic enzymes and oxidoreductases paired with the application of peroxides, can be a promising alternative for obtaining even better results in the dental bleaching process.

Hígado y SARS-CoV-2: aspectos claves de la literatura / Liver and SARS-CoV-2: Literature key aspects

Resumen El nuevo coronavirus del síndrome respiratorio agudo grave de tipo 2 (SARS-CoV-2), virus que se ha expandido por todo el mundo, produce una infección respiratoria aguda capaz de producir la muerte; sin embargo, el daño en otros órganos también es frecuente. Diversos estudios han evidenciado alteraciones en pruebas de lesión hepáticas, las cuales se han asociado con enfermedad grave y mayor estancia hospitalaria; así mismo, en la infección por el virus en pacientes con enfermedad hepática preexistente se observó una elevación significativa de las aminotransferasas durante el curso de la enfermedad y mayor riesgo de enfermedad grave. La explicación fisiopatológica de la afectación hepática en estos pacientes abarca el efecto citopático directo producido por la unión del virus a la enzima convertidora de la angiotensina II (ECA-II) a los hepatocitos y colangiocitos, una respuesta inmunitaria desproporcionada y, en algunos casos, la hepatotoxicidad por medicamentos.

Abstract The new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a virus that has spread around the world, causes an acute respiratory infection and it may also cause death. The damage that can cause in other organs is frequent. Many studies had also shown alterations in liver function tests, that are then related to serious illness and with hospitalization requirements. Moreover, in patients infected with the virus that had underlying liver disease, a significant increase in the level of aminotransferases was observed in the course of the disease. A greater risk of serious illness was also detected. The pathophysiological explanation of liver injury in those patients covers the direct cytopathic effect produced by binding the virus, the angiotensin-converting enzyme (ACE2) to the hepatocytes and the cholangiocytes, excessive immune response, and in some cases, drug-induced hepatotoxicity.

Formación de almidón retrogradado relacionado a niveles de amilosa en el almidón de papa (Solanum tuberosum) y chuño / Retrograded starch formation dependent on amylose level of potatoe starch (Solanum tuberosum) and chuño

INTRODUCCIÓN: la papa es el tubérculo más importante producido a nivel mundial como producto alimenticio. Una de las formas ancestrales de conservación de la papa en los países andinos es la obtención de un producto llamado chuño, obtenido a partir de las denominadas papas amargas. Existen pocos datos respecto a la composición química y nutricional del chuño y sobre los cambios producidos en el almidón durante su elaboración en el proceso de congelado-secado en condiciones específicas de temperatura y exposición a rayos ultravioleta. OBJETIVO: el objetivo del trabajo fue realizar una revisión bibliográfica respecto a cambios producidos en la relación de amilosa y amilopectina, la composición de almidón aislado de papa y la modificación de las características de este almidón en el proceso de elaboración de chuño. METODOLOGÍA: La revisión bibliográfica se ha realizado con la recopilación de tres fuentes referenciales de estudios realizados sobre el chuño y su proceso de elaboración, artículos sobre la estructura del almidón de papa y otros tubérculos del mismo género, artículos de otros productos alimenticios del Altiplano boliviano y peruano, y finalmente la influencia de los cambios de la estructura del almidón en el incremento de la formación de almidón retrogradado. RESULTADOS: la revisión bibliográfica realizada, señala que el proceso de elaboración de chuño eleva el porcentaje de amilosa en el contenido total de almidón, lo cual está relacionado a procesos de exposición a radiación UV y a cambios de temperaturas muy drásticos, que van entre -13,5 ºC y 16 ºC. Este proceso llevaría a la activación de enzimas, como amilasas, para la catálisis de reacciones de ruptura de enlaces como principal ruta del proceso; sin embargo, se podrían evaluar otras causas. CONCLUSIONES: el mayor porcentaje de amilosa permitiría la obtención de altos porcentajes de almidón retrogradado.

INTRODUCTION: the potato is the most important tuber produced worldwide as a food product. One of the ancestral ways of preserving pootatoes in the Andean countries is a product called chuño (traditional Andean freeze and sun-dried potato), obtained from the so-called bitter potatoes. There are few data regarding the chemical and nutritional composition of chuño and the changes produced in the starch during its preparation in the freeze-drying process under specific conditions of temperature and exposure to ultraviolet rays. OBJECTIVE: the objective of this article was to do a bibliographic review regarding changes produced in the amylose and amylopectin ratio, the composition of isolated potato starch and the modification of the characteristics of this starch in the process of making chuño. METHODOLOGY: the literature review methodology has the compilation of three reference sources of studies carried out on chuño and its production process, articles about the structure of potato starch and other tubers, research on other food products from the Bolivian and Peruvian of Altiplano and finally the influence of the changes in starch structure in relation to the increasing of retrograde starch formation. RESULTS: the results show that the process of making chuño increases the percentage of amylose in the total starch content, which is related to the processes of exposure to UV radiation and very drastic temperature changes, ranging between -13, 5 ºC and 16 ºC. This process would lead to the activation of enzymes, such as amylases, for the catalysis of bond breaking reactions as the main route of the process; however, other causes could be evaluated. CONCLUSIONS: the higher percentage of amylose would allow the obtaining of high percentages of retrograded starch.

Efeito de complexo enzimático na dieta para juvenis de pirarucu, Arapaima gigas / Effect of enzymatic complex in the diet of pirarucu, Arapaima gigas juveniles

O pirarucu, Arapaima gigas é um peixe carnívoro nativo da bacia amazônica. Como peixes carnívoros possuem baixa atividade de amilase, enzimas exógenas melhoram a digestibilidade de carboidratos em rações para aquacultura. O objetivo deste estudo foi avaliar a digestibilidade de níveis crescentes de complexo enzimático em dietas para juvenis de pirarucu (65,2 ± 0,4 g). O desenho experimental foi randomizado com quatro tratamentos [dietas contendo 0,25, 0,50, 0,75 e 1 g kg-1 de complexo enzimático adicionado (Allzyme® SSF®, EUA)] e um controle, com três réplicas com densidade de cinco peixes por unidade e 30 dias de duração. A digestibilidade aparente da matéria seca, proteína bruta e energia bruta foi calculada por quantificação de nutrientes e óxido de cromo nas dietas e fezes. A atividade enzimática, o glicogênio hepático e a proteína total foram determinados a partir de amostras do fígado e intestino anterior. A dieta com 1 g kg-1 de complexo enzimático resultou em um aumento da digestibilidade aparente de proteina bruta, energia bruta, matéria seca, glicogênio hepático e proteínas totais no fígado e intestino, mostrando a eficácia do complexo enzimático na dieta dos pirarucus. A acumulação mais alta de matéria seca, energia bruta e extrato etéreo na carcaça indicou o aumento de peso dos peixes tratados com complexo enzimático. A redução da atividade enzimática endógena (protease, lipase e amilase) sugeriu um aumento da eficácia do processo digestivo. Nossos resultados indicam que a inclusão de 1 g kg-1 do complexo enzimático na dietas de juvenis de pirarucu pode ser recomendada para obter maior digestibilidade de nutientes e performance produtiva. (AU)

Cambios en la función hepática causados por COVID-19 y su impacto en el resultado clínico del paciente: una revisión sistemática / Changes in liver function tests caused by COVID-19 and impact on patient outcome: a systematic review

Resumen Introducción: En marzo de 2020, la Organización Mundial de la Salud (OMS) decretó la pandemia de la enfermedad por coronavirus de 2019 (COVID-19), que consiste en la infección por coronavirus del síndrome respiratorio agudo grave de tipo 2 (SARS-CoV-2). Este virus utiliza la enzima convertidora de angiotensina II (ECA-II) como receptor celular humano, que está presente en el tejido pulmonar, cardíaco, gastrointestinal, hepático, renal y vascular, lo que configura un potencial de afectación multisistémica por parte del patógeno. El hígado puede resultar dañado tanto por la liberación excesiva de citocinas inflamatorias en COVID-19 como por la adopción de fármacos con potencial hepatotóxico en el tratamiento de sus síntomas. Objetivo: analizar la relación entre los cambios en la función hepática causados por el SARS-CoV-2 y su impacto en el pronóstico del paciente. Métodos: el presente estudio consiste en una revisión sistemática, realizada a partir de estudios seleccionados de las bases de datos PMC, LILACS y SciELO. Después de aplicar los criterios de inclusión y exclusión, se definieron 30 artículos para componer la base de datos de este estudio. Resultados: La enzima aspartato-aminotransferasa (AST) estaba aumentando en mayor prevalencia, con un total de 4695 casos, mientras que la alanina-aminotransferasa (ALT) estaba elevada en 3226 casos. Se observa que los pacientes que presentaban síntomas digestivos tenían más probabilidades de presentar daño hepatocelular y, en consecuencia, alteraciones enzimáticas. Además, la mortalidad ocurrió en el 28,9 % de los casos de pacientes con función hepática alterada, mientras que, en aquellos con función normal, esta tasa fue del 9 %. Conclusión: es evidente que existe una relación entre la afectación hepática por COVID-19 y su mortalidad. Sin embargo, todavía existe una limitación en la cantidad y, principalmente, en la homogeneidad de los estudios que realizaron dicha valoración.

Abstract Introduction: In March 2020, the World Health Organization declared COVID-19, a disease caused by SARS-CoV-2 infection, a global pandemic. This virus uses human angiotensin-converting enzyme 2 (ACE2) as its receptor for entry. ACE2 is found in pulmonary, cardiac, gastrointestinal, hepatic, renal and vascular tissues, thus posing a potential risk for multisystemic involvement. The excessive release of inflammatory cytokines in COVID-19, as well as the use of medicines with hepatotoxic potential for the treatment of its symptoms, can damage the liver. Objective: To analyze the relationship between changes in liver function tests caused by SARS-CoV-2 infection and their impact on patient prognosis. Methodology: This is a systematic review of studies selected from the PMC, LILACS and SciELO databases. After applying the inclusion and exclusion criteria, 30 articles were included in the final sample for analysis. Results: Elevated AST (aspartate aminotransferase) enzyme levels were reported most frequently and were found in 4 695 cases, while ALT (alanine aminotransferase) elevation was described in 3 226 cases. It was observed that patients with digestive symptoms were more likely to present hepatocellular damage and, consequently, enzymatic alterations. Furthermore, 28.9 % of individuals with impaired liver function died, compared to 9 % of patients with normal function. Conclusion: It is evident that there is a relationship between liver involvement in COVID-19 and mortality. However, there is still a limitation in the number and, more importantly, the homogeneity of the research that performed this assessment.

A construção histórica do conceito de enzima e sua abordagem em livros didáticos de biologia / Historical construction of the concept of the enzyme and approaches in biology textbooks

Resumo O uso de história e filosofia da ciência no ensino-aprendizagem é comumente negligenciado, linear e/ou descontextualizado nos livros didáticos. Isso aconteceria com a história do conceito de enzimas? Este trabalho busca investigar essa questão. Para a fundamentação teórica, foi realizada breve revisão bibliográfica, investigando-se como o conceito de enzimas é apresentado em nove livros didáticos, seguindo três categorias de análise. Encontrou-se, de forma geral, falta de interconexão nos assuntos de bioquímica, sendo as enzimas usualmente apresentadas apenas pelo modelo "chave-fechadura", que hoje não é representativo da complexidade do fenômeno. Além disso, foram observados limites conceituais decorrentes da ausência ou deficiência na contextualização histórica presente no material didático.

Abstract The use of the history and philosophy of science in teaching and learning is commonly neglected, linear, and/or out of context in textbooks. This article investigates whether this also occurs with the concept of enzymes. A brief review of the literature establishes the theoretical foundation to investigate how the concept of enzymes is presented in nine textbooks, following three different lines of analysis. A general lack of interconnection was seen in biochemistry topics, with enzymes usually only presented via the "lock-and-key" model, which does not best represent their complexity. Furthermore, conceptual limitations resulting from a lack of historical contextualization (partial or complete) were also observed.