COMPOSICIÓN NUTRICIONAL DE LA CARNE DE GUANACO DE LA PATAGONIA ARGENTINA / NUTRITIONAL COMPOSITION OF GUANACO MEAT FROM PATAGONIA, ARGENTINA

Introducción: Se considera a la carne de guanaco y sus derivados un producto cárnico consumible (Art. 261, CAA). El objetivo fue evaluar los aspectos nutricionales en cortes de uso comercial (lomo y peceto) de la carne de guanaco (Lama guanicoe guanicoe), del departamento Escalante (Chubut, Argentina) durante los años 2022 y 2023. Materiales y métodos: Se obtuvieron las muestras de 10 ejemplares machos adultos. Se determinó humedad (AOAC 950.46), proteínas (AOAC 928.08), grasas totales (AOAC 960.39), cenizas (AOAC 920.153), carbohidratos (cálculo por diferencia) y colesterol (Wiener lab®). Resultados: La composición centesimal de lomo y peceto, expresada en g/100 g en base húmeda, y el contenido de colesterol, expresado en mg/100 g en base húmeda, para el año 2022, en animales faenados en la estancia La Paulina, fue: humedad 75,1±0,13 y 5,2±0,06; proteínas 22,2±0,23 y 22,3±0,18; grasas totales 0,69±0,01 y 0,68±0,02; cenizas 0,85±0,03 y 0,88±0,04; carbohidratos 1,14 y 0,95; y colesterol 58,9±4,52 y 64,4±4,20, respectivamente. No se observaron diferencias estadísticas entre la composición de ambos cortes (p>0,05). La composición centesimal de lomo y peceto, expresada en g/100 g en base húmeda, y el contenido de colesterol, expresado en mg/100 g en base húmeda, para el año 2023 fue: humedad 76,6±0,14 y 76,7±0,17; proteínas 20,6±0,21 y 20,5±0,25; grasas totales 0,58±0,03 y 0,53±0,03; cenizas 1,07±0,04 y 1,02±0,02; carbohidratos 1,21 y 1,19; y colesterol 43,5±3,17 y 37,8±2,10, respectivamente. Se observó un mayor contenido de grasa en el corte lomo (p<0,05), mientras que no se observaron diferencias estadísticas (p>0,05) para el resto de los nutrientes. Conclusiones: El guanaco es una especie abundante y silvestre, muy atractiva para el consumo humano por sus cualidades nutritivas. Este alimento autóctono representa una opción alimentaria regional, con un potencial posicionamiento en el mercado nacional e internacional como una carne exótica. La carne de guanaco presenta un contenido de proteínas ligeramente mayor, un porcentaje de grasas totales significativamente menor y un nivel de colesterol ligeramente inferior, respecto a otras carnes rojas de consumo habitual

Introduction: Guanaco meat and its derivatives are considered a consumable meat product (Art. 261, CAA). The objective was to evaluate the nutritional aspects of commercially used cuts (loin and round) of guanaco meat (Lama guanicoe guanicoe) from the Escalante department (Chubut, Argentina) during the years 2022 and 2023. Materials and Methods: Samples were obtained from 10 adult male specimens. Moisture (AOAC 950.46), protein (AOAC 928.08), total fat (AOAC 960.39), ash (AOAC 920.153), carbohydrates (calculated by difference), and cholesterol (Wiener lab®) were determined. Results: The proximate composition of loin and round, expressed as g/100 g on a wet weight basis, and the cholesterol content, expressed as mg/100 g on a wet weight basis, for the year 2022, in animals slaughtered at La Paulina ranch, was as follows: moisture 75.1±0.13 and 75.2±0.06; protein 22.2±0.23 and 22.3±0.18; total fat 0.69±0.01 and 0.68±0.02; ash 0.85±0.03 and 0.88±0.04; carbohydrates 1.14 and 0.95; and cholesterol 58.9±4.52 and 64.4±4.20, respectively. No statistical differences were observed between the composition of both cuts (p>0.05). The proximate composition of loin and round, expressed as g/100 g on a wet weight basis, and the cholesterol content, expressed as mg/100 g on a wet weight basis, for the year 2023 was as follows: moisture 76.6±0.14 and 76.7±0.17; protein 20.6±0.21 and 20.5±0.25; total fat 0.58±0.03 and 0.53±0.03; ash 1.07±0.04 and 1.02±0.02; carbohydrates 1.21 and 1.19; and cholesterol 43.5±3.17 and 37.8±2.10, respectively. A higher fat content was observed in the loin cut (p<0.05), while no statistically significant differences were observed (p>0.05) for the rest of the nutrients. Conclusions: The guanaco is an abundant and wild species, highly attractive for human consumption due to its nutritional qualities. This native food represents a regional dietary option, with potential positioning in the national and international markets as an exotic meat. Guanaco meat has a slightly higher protein content, significantly lower total fat percentage, and a slightly lower cholesterol level compared to other commonly consumed red meats

Perfil de competencias esenciales que orientan la formación de los profesionales de la salud. Documento técnico. Segunda fase: Químico(a), farmacéutico(a) psicólogo(a), nutricionista (a) y cirujano (a), dentista peruano (a) / Profile of essential competencies that guide the training of health professionals. Technical document. Second phase: Chemist, pharmacist, psychologist, nutritionist and surgeon, Peruvian dentist

El perfil de competencias esenciales para el Químico (a) Farmacéutico (a), Psicólogo (a), Nutricionista y Cirujano (a) Dentista Peruano (a) que se incorporarán a trabajar al Sistema Nacional de Salud está conformado por un número mínimo de competencias esenciales que el Sistema Nacional de Salud demanda de los futuros profesionales, las cuales podrán ser complementadas con otras competencias que las escuelas o facultades de ciencias de la salud tengan a bien considerar en el marco de su autonomía universitaria. Cabe precisar, que las competencias esenciales para el profesional Obstetra, Biólogo, Tecnólogo Médico y Médico Veterinario están pendientes de aprobación, conforme a las funciones de la Autoridad Sanitaria. Finalmente, en el presente documento de competencias esenciales que orientan la formación de los profesionales de la salud. Segunda fase: Químico(a) Farmacéutico(a), Psicólogo (a), Nutricionista y Cirujano(a) Dentista Peruano (a), cada perfil está compuesto por los siguientes campos: 1. Descripción y rol del profesional 2. Perfil de competencias: a) Propósito. b) Competencias técnicas. c) Competencias conductuales

Planejamento, síntese e avaliação biológica de candidatos a fármacos: busca de inibidores epigenéticos da Sirtuína 2 Sir2 / Design, synthesis and biological evaluation of drug candidates: search for Sirtuin 2 (Sir 2) epigenetic inhibitors

As doenças negligenciadas são causadas por agentes infecciosos e parasitários, como vírus, bactérias, protozoários e helmintos. Essas doenças são prevalentes em populações de baixa renda que vivem em países em desenvolvimento e são responsáveis por incapacitar e levar milhares de pessoas à morte. Este nome se dá pois, apesar de sua grande relevância médica, recebem pouca atenção dos governos e indústrias farmacêuticas. Dentre essas doenças podemos destacar a Doença de Chagas, doença infecciosa causada pelo parasita hemoflagelado Trypanosoma cruzi. Endêmica em 21 países, com 6 a 7 milhões de pessoas infectadas resultando em 7500 mortes por ano. A quimioterapia disponível contra essa parasitose é baseada em apenas dois medicamentos, o benznidazol e o nifurtimox, ativos principalmente na fase aguda da doença e com efeitos adversos graves que comprometem a adesão ao tratamento e, além disso, apesar dos enormes esforços na pesquisa de novos agentes antichagásicos em nível nacional e internacional, na maioria realizada academicamente, ainda não foram encontradas alternativas terapêuticas para a doença, persistindo, assim, a necessidade de descoberta e desenvolvimento de novos fármacos. O início de um planejamento de um novo fármaco se dá pela definição de um alvo bioquímico a ser utilizado na busca de moléculas que possam exercer a função de inibidores ou moduladores, conforme a atividade biológica desejada. Neste sentido, as sirtuínas 2 (Sir2) são enzimas que se mostraram essenciais para o crescimento in vitro do T. cruzi em suas formas amastigota e epimastigota. No caso de tripanossomatídeos, em geral, a superexpressão de Sir2 está relacionada à sobrevivência de formas amastigotas. Assim, essas evidências indicam que a Sir2 de tripanosomatídeos tem grande potencial como alvo biológico na busca e desenvolvimento de novos fármacos antichagásicos. O objetivo principal deste projeto foi identificar moléculas que apresentaram atividade inibitória para a sirtuína 2 de T. cruzi por meio da utilização da estratégia de Planejamento de Fármacos Baseada no Ligante - Ligand Based Drug Design (LBDD) e o desenvolvimento de análogos dos inibidores da Sir2. A modificação molecular está entre algumas das técnicas tradicionais usadas no desenvolvimento racional de um fármaco, e é usada principalmente no desenvolvimento de análogos, e busca melhorar as propriedades farmacocinéticas e/ou farmacodinâmicas de um protótipo, obter propriedades de interação semelhantes ao alvo e, em alguns casos, revelar uma atividade biológica. Com este intuito, análogos do sirtinol e da salermida foram sintetizados e uma nova rota sintética utilizando o microrreator em fluxo contínuo foi desenvolvida e apresentou rendimento superior quando comparado à síntese em bancada. A partir desta metodologia foram obtidos 20 compostos. Os ensaios in vitro contra formas amastigotas do T. cruzi indicaram que 8 compostos inibiram a atividade parasitária em mais de 50%, na dose de 10 µM, sendo que alguns destes apresentaram maior inibição parasitária quando comparados ao benznidazol, o fármaco de referência e único disponível no Brasil. Com estes resultados preliminares, novos ensaios estão sendo realizados para identificar potência e mecanismo de ação destes candidatos a agentes tripanomicidas

Neglected diseases are caused by infectious and parasitic agents such as viruses, bacteria, protozoa and helminths. These diseases are prevalent in low-income populations living in developing countries and are responsible for disabling and killing thousands of people. They get this name because, despite their great medical relevance, they end up receiving little attention from governments and pharmaceutical industries. Among these diseases, we can highlight Chagas disease, an infectious endemic disease caused by the hemoflagellate parasite Trypanosoma cruzi. This disease is endemic in 21 countries, with 6 to 7 million people infected resulting in 7,500 deaths per year. Chemotherapy is based on just two drugs, benznidazole and nifurtimox, which are mainly active in the acute phase of the disease. These drugs have adverse effects that compromise adherence, even more, considering that they are not effective from the point of view of the chronic phase of the disease. Despite the enormous efforts in researching new anti-chagasic agents at the national and international level, and mostly carried out academically, therapeutic alternatives for the disease have not yet been found, thus, the need for the discovery and development of new drugs persists. Sirtuins 2 (Sir2) are enzymes that have been shown to be essential for the in vitro growth of T. cruzi in its amastigote and epimastigote forms. In the case of trypanosomatids in general, Sir2 overexpression is related to the survival of amastigote forms. Sir2 inhibitors, such as sirtinol, have shown efficacy in leishmanicides. Thus, these evidences indicate that Sir2 from trypanosomatids can be considered as a biological target in the search and development of new anti-chagasic drugs. The beginning of a new drug planning study is the definition of a biochemical target to be used in the search for molecules that can play the role of inhibitors or modulators, according to the desired biological activity. The main objective of this project was to identify molecules that presented inhibitory activity to sirtuin 2 of T. cruzi using the Ligand Based Drug Design (LBDD) strategy of planning and the development of analogues of Sir2 inhibitors. Molecular modification is a traditional technique used in the rational development of a drug, as well as the use of natural products, combinatorial chemistry, high-throughput screening (HTS), among others. Mainly used in the development of analogues, molecular modification is applied for different purposes, among them, it seeks to improve the pharmacokinetic and/or pharmacodynamic properties of a prototype, obtain target-like interaction properties and, in some cases, reveal an activity biological. For this purpose, analogues of sirtinol and salermide were synthesized and a new synthetic route using the microreactor in continuous flow was developed and presented superior yield when compared to benchtop synthesis. From this methodology, 20 compounds were obtained. in vitro assays against amastigote forms of T. cruzi indicated that 8 compounds inhibited parasitic activity by more than 50% at a dose of 10 µM, and some of these showed greater parasitic inhibition when compared to benznidazole, the reference drug, and only available in Brazil. With these preliminary results, new assays are being carried out to identify the potency and mechanism of action of these candidate trypanocidal agents

Self-regulated learning of Natural Sciences and Mathematics future teachers: learning strategies, self-efficacy, and socio-demographic factors

Teacher education programs should have as one of their purposes the promotion of self-regulatory skills for learning among students who aspire to be teachers so that they can take a leading role in their learning and foster these skills in their future students. Considering the importance of knowing what students in teacher education programs do to study and learn, as well as how efficacious they feel to deal with academic demands, this study is part of a larger research and aims to investigate the learning and study strategies and self-efficacy for learning beliefs of 220 students enrolled in teacher education programs in Biological Sciences, Chemistry, Physics and Mathematics of a Higher Education Institution in the state of Piauí, and examine them in relation to age, gender, licentiate area, and course semester. Brazilian translations of the Learning and Study Strategies Inventory (LASSI ­ Third Edition) and the Self-efficacy for Learning Form were used for data collection. Scales were administered in the classrooms both through online platforms and in paper and pencil. Nonparametric inferential statistical pproaches were used to test hypotheses regarding group differences. Statistically significant differences were found in LASSI in relation to gender, licentiate area, and course semester. Overall, students in Physics dealt better with anxiety; in Mathematics showed more favorable attitudes towards learning; in Chemistry reported an aging their time better; in Biological Science showed significantly lower scores on many scales than did other students. Findings from this study could help inform curricular design decisions regarding teacher education programs and inform the design of interventions to strengthen the learning and study strategies and the self-efficacy for learning beliefs of future teachers.

O uso de mapas conceituais e curtas metragens de temática química no estudo de temas da Sociologia / The use of conceptual maps and short films about chemical theme in the study of sociology themes

O objetivo deste estudo interdisciplinar foi usar curtas metragens produzidos por estudantes do ensino médio sobre temas da Química para o ensino de Sociologia. Neste sentido, foram produzidos mapas conceituais pelos estudantes, após a discussão dos curtas metragens, sob uma perspectiva sociológica. Nossos resultados mostram que os mapas conceituais podem atuar como instrumentos facilitadores para a aprendizagem, capazes de estimular a pesquisa e promover a autonomia dos estudantes durante o processo de construção do conhecimento.

The aimof this interdisciplinary study was useshort films produced by high school students about chemical themes to Sociology teaching. In this way, conceptual maps were constructedby students after short films discussion under a social perspective. Our results showed that conceptual maps could act as facilitating learning instrument, able to stimulate research and to promote student autonomy during the knowledge construction process.

Detección de aflatoxina M1 en muestras de leche cruda de vacas en tanques de enfriamiento en Boyacá (Colombia) / Detection of aflatoxin M1 in raw cow milk samples in cooling tanks in Boyacá (Colombia)

RESUMEN Una de las principales formas de contaminación de la leche con micotoxinas es el consumo de alimentos fermentados que se encuentran contaminados con mohos principalmente de Aspergillus spp., los cuales producen toxinas que pueden llegar a constituirse como un problema para la salud publica debido a su estabilidad térmica y química. El objetivo del presente trabajo fue detectar las concentraciones de aflatoxina M1 en muestras de leche de vacas en tanques de enfriamiento en cuatro municipios del departamento de Boyacá durante un año, determinando las variaciones de acuerdo con la temporada. Se realizó un estudio de corte longitudinal, descriptivo cuantitativo. Se seleccionaron aleatoriamente cuatro tanques de enfriamiento de cuatro municipios distintos del departamento; cada uno se muestreó dos veces al mes durante todo el período de estudio y se procesaron mediante metodología Charm Ez Lite . Se realizó un ANDEVA para determinar las diferencias estadísticas entre las concentraciones de la aflatoxina M1 por cada trimestre. Se determinaron diferencias estadísticas entre cada uno de los trimestres del estudio encontrando un porcentaje de positividad de 74,06% del total de muestras positivas en los trimestres de verano. 28,12% (108) de las muestras tomadas durante todo el estudio fueron positivas, con concentraciones de la toxina que oscilaron entre 0,5 y 2,0 μg/Kg de leche. Se determinó por primera vez en el departamento de Boyacá las concentraciones y variaciones estacionales de aflatoxina M1 en muestras de tanques de enfriamiento de leche, encontrando las mayores concentraciones y número de casos positivos de aflatoxina M1 en los meses de verano.

ABSTRACT One of the main forms of contamination of milk with mycotoxins is the consumption of fermented foods that are contaminated with mold, mainly Aspergillus spp, which produce toxins that can become a public health problem due to their thermal and chemical stability. The objective of the present work was to detect aflatoxin M1 concentrations in cows' milk samples in cooling tanks in four municipalities of the department of Boyacá for one year, determining the variations according to the season. A longitudinal, quantitative descriptive study was carried out, four cooling tanks from four different municipalities in the department were randomly selected, each tank, in each municipality, was sampled twice a month throughout the study period and processed using Charm methodology Ez Lite®, an ANDEVA was performed to determine the statistical differences between aflatoxin M1 concentrations for each quarter. Statistical differences were determined between each of the quarters of the study, finding a positivity percentage of 74.06% of the total positive samples in the summer quarters. 28.12% (108) of the samples taken throughout the study were positive, with toxin concentrations ranging between 0.5 and 2.0 μg/Kg of milk. Seasonal concentrations and variations of aflatoxin M1 in milk cooling tank samples were determined for the first time in the department of Boyacá, finding the highest concentrations and number of positive cases of aflatoxin M1 in the summer months.

Estrategias didácticas innovadoras y actitud emprendedora en estudiantes universitarios de biotecnología y química / Innovative teaching strategies and entrepreneurial attitude in Biotechnology and Chemistry university students

Introducción: El emprendimiento es la actitud y aptitud que toma un sujeto para iniciar un nuevo proyecto a través de ideas y oportunidades, su gestión eficiente dota al estudiante universitario de las herramientas necesarias para su implementación. Objetivo: Evaluar la percepción de los estudiantes sobre las estrategias didácticas aplicadas en la cátedra de Emprendimiento de Biotecnología y Química de la Escuela Superior Politécnica de Chimborazo (ESPOCH). Métodos: Se realizó una investigación exploratoria con la participación de 50 estudiantes de Biotecnología y Química de la universidad mencionada, aplicando durante la asignatura de Emprendimiento una estrategia didáctica innovadora, previamente evaluada como pertinente por un grupo de 13 expertos. La percepción del estudiantado fue evaluada a través de un cuestionario (7 preguntas), aplicado al finalizar la asignatura, analizando los datos con estadística descriptiva e inferencial. Resultados: Se calificó las preguntas incluidas en el cuestionario con el máximo valor de acuerdo; existiendo diferencias significativas en relación al sexo en la percepción sobre la disminución de los niveles de estrés durante la clase, cambios en la actitud emprendedora y utilidad de la asignatura para el futuro desarrollo emprendedor. La prueba Rho de Spearman determinó interesantes correlaciones entre las preguntas del cuestionario, especialmente las relacionadas con que la generación de un buen ambiente de aprendizaje, la disminución de los niveles de estrés en la clase y las relaciones profesor-estudiante. Conclusiones: La aplicación de estrategias didácticas-innovadoras mejora el impacto que la asignatura de Emprendimiento tiene sobre la formación de la actitud emprendedora del estudiantado(AU)

Introduction: Entrepreneurship is the attitude and aptitude that a subject takes to start a new project through ideas and opportunities, its efficient management allows equipping the university student with the necessary tools for its implementation. Objective: To evaluate the students' perception of the didactic strategies applied in the Chair of Entrepreneurship in Biotechnology and Chemistry careers of Escuela Superior Politécnica de Chimborazo (ESPOCH). Methods: An exploratory research was carried out with the participation of 50 Biotechnology and Chemistry students from the mentioned university, to whom an innovative didactic strategy was applied during the Entrepreneurship course, which was previously evaluated as relevant by a group of 13 experts. The perception of the students was evaluated through a questionnaire with 7 questions, which was applied at the end of the course and whose data were analyzed by applying descriptive and inferential statistics. Results: Most of the students rated the questions included in the questionnaire with the highest value of agreement. There are significant differences according to gender in the perception of the decrease in stress levels during class, changes in entrepreneurial attitude and the usefulness of the subject for future entrepreneurial development. Using the Spearman Rho test, interesting correlations were determined between the questions of the questionnaire, especially those related to the generation of a good learning environment, the reduction of stress levels in the class and teacher-student relationships. Conclusions: The application of didactic-innovative strategies improves the impact that the Entrepreneurship course has on the entrepreneurial attitude formation of the student body(AU)

Partnering ethics and chemistry in secondary and university STEM education via an innovatively designed periodic table of chemical elements / Ética y química asociadas en la educación secundaria y universitaria STEM, a través de una tabla periódica de elementos químicos de diseño innovador / Associando ética e química na educação stem secundária e universitária via uma tabela periódica de elementos químicos desenvolvida de forma innovadora

As declared by the United Nations, 2019 is the International Year of the Periodic Table of Chemical Elements. Accordingly, an innovative new Periodic Table of Chemical Elements and Ethics [PETE] has been developed as an educational tool for secondary and university STEM (Science, Technology, Engineering and Mathematics) education. The tool is designed to be used in a case-based approache that is feasible to both individual and small group learners. Specifically, with the new periodic table, STEM becomes aligned with STSE (Science and Technology on Society and Environment), laying a curricular pathway for integrating discussions of ethics into the teaching of chemistry. Presented is the table, as well as sources for pairable ethics cases, and guidance for teachers to create curriculum which facilitates connections between ethics, chemistry, and society.

Según lo declarado por las Naciones Unidas, 2019 es el Año Internacional de la Tabla Periódica de Elementos Químicos. En consecuencia, se ha desarrollado una nueva e innovadora tabla periódica de elementos químicos y ética [PETE] como una herramienta educativa para la educación secundaria y universitaria STEM (Ciencia, Tecnología, Ingeniería y Matemáticas). La herramienta está diseñada para usarse en un enfoque basado en casos que sea factible tanto para estudiantes individuales como para grupos pequeños. Específicamente, con la nueva tabla periódica, STEM se alinea con STSE (Ciencia y Tecnología en Sociedad y Medio Ambiente), estableciendo una vía curricular para integrar las discusiones de ética en la enseñanza de la química. Se presenta la tabla, así como las fuentes de casos de ética que se pueden pactar, y orientación para que los maestros creen un plan de estudios que facilite las conexiones entre la ética, la química y la sociedad.

Como declarado pelas Nações Unidas, 2019 é o Ano Internacional da Tabela Periódica de Elementos Químicos. Portanto, uma inovadora e nova Tabela Periódica de Elementos Químicos e Ética (PETE, sigla em inglês) foi desenvolvida como uma ferramenta educacional para educação STEM (sigla em inglês para Ciência, Tecnologia, Engenharia e Matemática) secundária e universitária. A ferramenta é elaborada para ser usada em uma abordagem baseada em casos, viável tanto para aprendizagem individual como de pequenos grupos. Especificamente, com a nova tabela periódica, STEM se alinha com STSE (sigla em inglês para Ciência e Tecnologia na Sociedade e Ambiente), estabelecendo uma via curricular para integrar discussões de ética no ensino de química. Apresenta-se a tabela, bem como fontes de casos éticos pareados, e orientação para professores criarem um currículo que facilite conexões entre ética, química e sociedade.

Association between metal cobalt exposure and the risk of congenital heart defect occurrence in offspring: a multi-hospital case-control study

BACKGROUND@#Many studies have investigated heavy metal exposure could increase the occurrence of congenital heart defects (CHDs). However, there are limited data regarding the relationship between cobalt exposure and CHD occurrence in offspring. The aim of this study was to analyze the association between cobalt exposure in mothers and the risk of CHDs in offspring.@*MATERIALS AND METHODS@#In order to explore the association between cobalt exposure and occurrence of congenital heart defect (CHD), a case-control study with 490 controls and 399 cases with CHDs in China were developed. The concentrations of cobalt in hair of pregnant woman and fetal placental tissue were measured and processed by a logistic regression analysis to explore the relationship between cobalt exposure and risk of CHDs.@*RESULTS@#The median concentration of hair cobalt in the control and case group was 0.023 ng/mg and 0.033 ng/mg (aOR, 1.837; 95% CI, 1.468-2.299; P < 0.001), respectively. And the median (5-95% range) fetal placental cobalt concentrations were 19.350 ng/g and 42.500 ng/g (aOR, 2.924; 95% CI, 2.211-3.868; P < 0.001) in the control and case groups, respectively. Significant differences in the middle level of cobalt in hair were found in the different CHD subtypes, including septal defects, conotruncal defects, right ventricular outflow tract obstruction, and left ventricular outflow tract obstruction (P < 0.001). Dramatically, different cobalt concentrations in fetal placental tissue were found in all subtypes of cases with CHDs (P < 0.01).@*CONCLUSIONS@#The finding suggested that the occurrence of CHDs may be associated with cobalt exposure.

An overview of COVID-19 / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection emerged in Wuhan City, Hubei Province, China in December 2019. By Feb. 11, 2020, the World Health Organization (WHO) officially named the disease resulting from infection with SARS-CoV-2 as coronavirus disease 2019 (COVID-19). COVID-19 represents a spectrum of clinical manifestations that typically include fever, dry cough, and fatigue, often with pulmonary involvement. SARS-CoV-2 is highly contagious and most individuals within the population at large are susceptible to infection. Wild animal hosts and infected patients are currently the main sources of disease which is transmitted via respiratory droplets and direct contact. Since the outbreak, the Chinese government and scientific community have acted rapidly to identify the causative agent and promptly shared the viral gene sequence, and have carried out measures to contain the epidemic. Meanwhile, recent research has revealed critical aspects of SARS-CoV-2 biology and disease pathogenesis; other studies have focused on epidemiology, clinical features, diagnosis, management, as well as drug and vaccine development. This review aims to summarize the latest research findings and to provide expert consensus. We will also share ongoing efforts and experience in China, which may provide insight on how to contain the epidemic and improve our understanding of this emerging infectious disease, together with updated guidance for prevention, control, and critical management of this pandemic.

Clinical efficacy of different waves of electroacupuncture on knee osteoarthritis and its effect on TGF-β1 in joint fluid / 中国针灸

OBJECTIVE@#To observe the therapeutic effects of different waves of electroacupuncture (EA) on knee osteoarthritis (KOA), and to explore the mechanism of different waves of EA on promoting cartilage repair.@*METHODS@#Ninety- seven patients with KOA were randomly divided into a dilatational wave group (32 cases, 2 cases dropped off), a continuous wave group (32 cases, 2 cases dropped off) and a discontinuous wave group (33 cases, 3 cases dropped off). The same acupoints of Xuehai (SP 10), Liangqiu (ST 34), Dubi (ST 35) and Neixiyan (EX-LE 4) were selected in the three groups. The dilatational wave (frequency of 2 Hz/10 Hz) was used in the dilatational wave group, the continuous wave (frequency of 10 Hz) was used in the continuous wave group, and the discontinuous wave (frequency of 10 Hz) was used in the discontinuous wave group. All the needles were retained for 30 min. All the treatment was given 3 times a week (on Monday, Wednesday and Friday) for 4 weeks. Lysholm knees scoring scale (LKSS) was used to evaluate the knee joint function before and after treatment, and the content of transforming growth factor-β1 (TGF-β1) in the joint effusion before and after treatment was determined by enzyme-linked immunosorbent assay (ELISA).@*RESULTS@#Compared before treatment, the total score and each score of LKSS were increased after treatment in the three groups (all <0.05). The improvements of total score, pain score, instability score, swelling score of LKSS in the continuous wave group and the dilatational wave group were superior to those in the discontinuous wave group (all <0.05). The content of TGF-β1 in the joint effusion in each group was increased after treatment (<0.05), and the improvement in dilatational wave group was superior to thoes in the continuous wave group and the discontinuous wave group (all <0.05).@*CONCLUSION@#The three different waves of EA could all improve the clinical symptoms of KOA, which may promote cartilage repair by increasing TGF-β1 content. The dilatational wave had the best overall effect, which can be used as a clinical optimal treatment.

Expression optimization and molecular modification of heparin C5 epimerase / 生物工程学报

Heparin and heparan sulfate are a class of glycosaminoglycans for clinical anticoagulation. Heparosan N-sulfate-glucuronate 5-epimerase (C5, EC 5.1.3.17) is a critical modifying enzyme in the synthesis of heparin and heparan sulfate, and catalyzes the inversion of carboxyl group at position 5 on D-glucuronic acid (D-GlcA) of N-sulfoheparosan to form L-iduronic acid (L-IdoA). In this study, the heparin C5 epimerase gene Glce from zebrafish was expressed and molecularly modified in Escherichia coli. After comparing three expression vectors of pET-20b (+), pET-28a (+) and pCold Ⅲ, C5 activity reached the highest ((1 873.61±5.42) U/L) with the vector pCold Ⅲ. Then we fused the solution-promoting label SET2 at the N-terminal for increasing the soluble expression of C5. As a result, the soluble protein expression was increased by 50% compared with the control, and the enzyme activity reached (2 409±6.43) U/L. Based on this, site-directed mutations near the substrate binding pocket were performed through rational design, the optimal mutant (V153R) enzyme activity and specific enzyme activity were (5 804±5.63) U/L and (145.1±2.33) U/mg, respectively 2.41-fold and 2.28-fold of the original enzyme. Modification and expression optimization of heparin C5 epimerase has laid the foundation for heparin enzymatic catalytic biosynthesis.

Screening and evaluation of saline-alkali-tolerant and growth-promoting bacteria / 生物工程学报

Salinity is the most important factor for the growth of crops. It is an effective method to alleviate the toxic effect caused by salt stress using saline-alkali-tolerant and growth-promoting bacteria in agriculture. Seven salt-tolerant bacteria were screened from saline-alkali soil, and the abilities of EPS production, alkalinity reduction and IAA production of the selected strains were investigated. A dominant strain DB01 was evaluated. The abilities of EPS production, alkalinity reduction and IAA production of strain DB01 were 0.21 g/g, 8.7% and 8.97 mg/L, respectively. The isolate was identified as Halomonas aquamarina by partial sequencing analysis of its 16S rRNA genes, and had the ability to inhibit the growth of Fusarium oxysporum f. sp., Alternaria solani, Phytophthora sojae and Rhizoctonia cerealis. It also could promote root length and germination rate of wheat seedlings under salt stress. Halomonas aquamarina can provide theoretical basis for the development of soil microbial resources and the application in saline-alkali soil improvement.

Research progress of phase separation of intracellular biological macromolecules / 生物工程学报

The phenomenon of phase separation of intracellular biological macromolecules is an emerging research field that has received great attention in recent years. As an aggregation and compartment mechanism of cell biochemical reactions, it widely exists in nature and participates in important physiological processes such as gene transcription and regulation, as well as influences organism's response to external stimuli. Disequilibrium of phase separation may lead to the occurrence of some major diseases. Researchers in cross-cutting fields are trying to examine dementia and other related diseases from a new perspective of phase separation, exploring its molecular mechanism and the potential possibility of intervention and treatment. This review intends to introduce the latest research progress in this field, summarize the major research directions, biochemical basis, its relationship with disease occurrence, and giving a future perspective of key problems to focus on.

Antagonistic activity of volatile metabolites from Trichoderma asperellum / 生物工程学报

Trichoderma spp. is a kind of filamentous fungi with important biocontrol value. Twelve strains of Trichoderma spp. were isolated from the soils of different types of crops in Shaoxing, Zhejiang and Foshan, Guangdong. The antagonistic resistance to Fusarium oxysporum was compared by plate confrontation test. The further analysis of volatile secondary metabolites for two strains were carried out using HS-SPME-GC-MS analysis. The results showed that T. asperellum ZJSX5003 and GDFS1009 had fast growth ability, and the inhibition effects on F. oxysporum were 73% and 74% respectively. Six identical volatile metabolites were detected as follows 2-Methyl-1-propanol, 3-Methyl-1-butanol, 3-Methyl-3-buten-1-ol, Acetyl methyl carbinol, Butane-2,3-diol and 6-n-pentyl-2H-pyran-2-one (6-PAP). Among them, 6-PAP was validated to have a higher inhibitory effect on F. oxysporum in vitro. This study will provide basis for the development of biocontrol agents with metabolites of Trichoderma, such as 6-PAP.

Characteristics of selenium nanoparticles synthesized by cell-free supernatant Cupriavidus sp. SHE / 生物工程学报

In recent years, selenium nanoparticles (SeNPs) have been widely used in many fields such as nanotechnology, biomedicine and environmental remediation due to their good electrical conductivity, photothermal properties and anticancer properties. In this study, the cell-free supernatant, whole cell and the cell-free extracts of the strain Cupriavidus sp. SHE were used to synthesize SeNPs, and several methods were applied to analyze the crystal structure and surface functional groups of the nanoparticles. Finally, Pseudomonas sp. PI1 (G⁺) and Escherichia coli BL21 (G⁻) were selected to investigate the antibacterial properties of SeNPs. Cell-free supernatant, whole cell and cell-free extracts of the strain could synthesize SeNPs. As for the cell-free supernatant, selenite concentration of 5 mmol/L and pH=7 were favorable for the synthesis of SeNPs. TEM images show that the average size of nanospheres synthesized by the supernatant was 196 nm. XRD analysis indicates the hexagonal crystals structure of SeNPs. FTIR and SDS-PAGE confirmed the proteins bound to the surfaces of SeNPs. SeNPs synthesized by cell-free supernatant showed no antimicrobial activities against Pseudomonas sp. PI1 and Escherichia coli BL21 (DE3). These results suggest that proteins played an important role in biotransformation of SeNPs in an eco-friendly process, and SeNPs synthesized in this study were non-toxic and biologically compatible, which might be applied in other fields in the future.

High efficient assimilation of NO₃⁻-N with coproduction of microalgal proteins by Chlorella pyrenoidosa / 生物工程学报

The aim of this study was to establish a novel technology using microalgae for NO₃⁻ removal from high concentration wastewater and conversion to algal proteins. The effects of cultivation modes and illumination modes on the biomass yield, NO₃⁻ assimilation rate and algal protein yield were first investigated in shaking flasks for mixotrophic cultivation of Chlorella pyrenoidosa, and subsequently the scale-up verification in 5-L photo fermenter was successfully conducted. Fed-batch cultivation without medium recycling was the best cultivation mode in shaking flask system, in which the highest biomass yield (35.95 g/L), the average NO₃⁻ assimilation rate (2.06 g/(L·d)) and algal protein content (up to 42.44% of dry weight) were achieved. By using a staged increase of light intensity as illumination modes, the specific growth rate of cells could be significantly promoted to the highest (0.65 d⁻¹). After a 128-hour continuous cultivation in a 5-L photo fermenter, the highest biomass yield and the average NO₃⁻ assimilation rate were reached to 66.22 g/L and 4.38 g/(L·d) respectively, with the highest algal protein content at 47.13% of dry weight. Our study could provide a photo fermentation technology of microalgae for highly efficient treatment of waste industrial nitric acid and/or high concentration nitrate wastewater. This microalgae-based bioconversion process could coproduce protein-rich microalgal biomass, which facilitates the resource utilization of these type wastewater by trash-to-treasure conversion.

The 40-91 aa sequence of porcine epidemic diarrhea virus ORF3 protein is the key structural domain controlling its location in cytoplasm / 生物工程学报

ORF3 protein, the single accessory protein encoded by porcine epidemic diarrhea virus (PEDV), is related to viral pathogenicity. In order to determine the cytoplasmic location signal of PEDV ORF3, we constructed a series of recombinant plasmids carrying full-length or truncated segments of PEDV DR13 ORF3 protein. When the acquired plasmids were transfected into Vero cells, expression and distribution of the EGFP-fused full-length ORF3 protein and its truncated forms in the cells were observed by laser confocal microscopy. The results showed that ORF3 protein or their truncated forms containing 40-91 aa segment including two transmembrane domains were localized in the cytoplasm, whereas ORF3 truncated peptides without the 40-91 aa segment were distributed in the whole cell (in both cytoplasm and nucleus). This suggests that the 40-91 aa is the key structural domain determining cytoplasmic location of PEDV ORF3 protein. The discovery provides reference for further clarifying intracellular transport and biological function of PEDV ORF3 protein.

Progress in shark single-domain antibody / 生物工程学报

Monoclonal antibody (mAb) is an important biological macromolecule and widely used in immune detection, in vitro diagnostics, and drug discovery. However, the inherent properties of mAb restrict its further development, such as high molecular weight and complex structure. Therefore, there is an urgent need to develop alternatives for mAb. Various types of miniaturized antibodies have been developed, among which the variable domain of immunoglobulin new antigen receptor (VNAR) is very attractive. The shark single-domain antibody, also known as shark VNAR, is an antigen-binding domain obtained by genetic engineering technology based on the immunoglobulin new antigen receptor (IgNAR) that naturally exists in selachimorpha. It has a molecular weight of 12 kDa, which is the smallest antigen-binding domain found in the known vertebrates at present. Compared with mAb, the shark VNAR exhibits various superiorities, such as low molecular weight, high affinity, tolerance to the harsh environment, good water solubility, strong tissue penetration, and recognition of the hidden epitopes. It has attracted wide attention in the fields of immunochemical reagents and drug discovery. In this review, various aspects of shark VNAR are elaborated, including the structural and functional characteristics, generating and humanization techniques, affinity maturation strategies, application fields, advantages and disadvantages, and prospects.

Research progress in structure and function of pectin methylesterase / 生物工程学报

Pectin methylesterase (PME) is an important pectinase that hydrolyzes methyl esters in pectin to release methanol and reduce the degree of methylation of pectin. At present, it has broad application prospects in food processing, tea beverage, paper making and other production processes. With the in-depth study of PME, the crystal structures with different sources have been reported. Analysis of these resolved crystal structures reveals that PME belongs to the right-hand parallel β-helix structure, and its catalytic residues are two aspartic acids and a glutamine, which play the role of general acid-base, nucleophile and stable intermediate, in the catalytic process. At the same time, the substrate specificity is analyzed to understand the recognition mechanism of the substrate and active sites. This paper systematically reviews these related aspects.