Actividad antimicrobiana de weissella confusa y sus metabolitos frente a escherichia coli y klebsiella pneumoniae

Título en ingles: Antimicrobial activity of Weissella confuse and its metabolites against Escherichia coli and  Klebsiella pneumoniaeResumen: Con el fin evaluar el campo de aplicación potencial de una bacteria ácido láctica y de sus metabolitos, se realizó la cinética de la actividad antimicrobiana de W. confusa y de sus  metabolitos contra E. coli, y K. pneumoniae, dos patógenos causantes de enfermedades transmitidas por alimentos. La producción de W. confusa se realizó por fermentación discontinua en sustrato comercial MRS. Se realizaron tres fermentaciones durante 6 horas, sin aireación, agitación continúa 33°C y 100 rpm. Cada hora de fermentación se separaron tres sustancias biológicas, W. confusa con sus metabolitos (W+W10b), células de W. confusa libres de metabolitos (W) y metabolito (W10b) y se midió la actividad antimicrobiana contra los patógenos E. coli, y K. pneumoniae. Se encontraron diferencias estadísticas significativas entre tratamientos y tiempo de fermentación. Para E. coli el tratamiento W presentó la mayor actividad antimicrobiana, la cual se obtuvo entre la cuarta y sexta hora de fermentación (2.45 cm de diámetro promedio de inhibición). Para K. pneumoniae, los tratamientos W y W+W10b presentaron actividad antimicrobiana entre la cuarta y quinta hora de fermentación, sin diferencia significativa entre ellos. W. confusa y el metabolito W10b demostraron poseer capacidad antimicrobiana contra E. coli y K. pneumoniae, lo cual sugiere que W. confusa y W10b podrían utilizarse como alternativa de bioconservación o bioprotección de alimentos frescos y procesados, para alimentación humana y animal; y podría convertirse en una alternativa al uso de antibióticos para enfermedades causadas por E. coli y K. pneumoniae.Palabras clave: bioconservación, alimentos, enfermedades, aplicaciones biotecnológicas.Summary: The kinetic of antimicrobial activity ofWeissella confusa and their metabolites against E. coli, and K. pneumoniae, (two pathogens causing foodborne illness) was evaluated, in order to know the possible use in food processing. W. confusa was produced by batch fermentation using MRS commercial substrate. Three fermentations, of 6 hours at 33 ° C, without aeration, stirring continuously (100 rpm) were performed. In every hour of fermentation, three biological substances, W. confusa with their metabolites (W + W10b), W. confusa free cells metabolites (W), and metabolite (W10b) were separated, and subsequently the antimicrobial activity against pathogenic E. coli and K. pneumoniae was measured. Statistically significant differences between treatments and fermentation time were found. Treatment (W) against E. coli, showed the greatest antimicrobial activity, it was obtained between the fourth and the sixth hours of fermentation (2.45 cm inhibition diameter average). In treatments W and W + W10b against K. pneumoniae, statistically significant differences between them were not found. The antimicrobial activity was shown between the fourth and fifth hour of fermentation. W. confusa and W10b have antimicrobial activity against E. coli andK. pneumoniae, suggesting that W and W10b could be used as an alternative to biopreservation or bioprotection of fresh and processed food for human and animal consumption, and could become an alternative to antibiotics used for diseases caused by E. coli and K. pneumoniae.Key words: bioconservation, food, diseases, biotechnology applications

Rendimiento de fibra de dos variedades de Abacá (Musa textiles) en tres densidades de Siembra

The objective of this research was to evaluate the yield of two varieties of abaca (Musa textiles) in three planting densities, in the first stage of crop production at 24 months of age, in Santo Domingo de los Tsáchilas; the Bungalanón and Tangongón varieties were established. The test consisted of 24 experimental units consisting of 70 m2. A randomized complete block design was used with a 2x3 factorial with four repetitions; The following planting densities were used: 816 (3.5 x 3.5 m), 952 (3.5 x 3 m) and 1111 (3 x 3 m) plants ha-1. The Tangongón variety reached the best results in plant height with 417.72 cm, pseudostem diameter with 20.17 cm and 8.64 leaves per plant; and the Bungalanón variety obtained the highest number of suckers with 19.53. The Tangongón presented the highest yield of dry fiber with 1.27 kg, with the highest weight of the pseudostem (40.73 kg) and tuxedo (18.56 kg). 96.41% was wasted in the process of obtaining fiber and only 3.59% is what is marketed as fiber, obtaining 30% as second category fiberLa presente investigación tuvo como objetivo evaluar el rendimiento de dos variedades de abacá (Musa textiles) en tres densidades de siembra, en la primera etapa de producción del cultivo a los 24 meses de edad, en Santo Domingo de los Tsáchilas; se establecieron las variedades Bungalanón y Tangongón. El ensayo estuvo conformado por 24 unidades experimentales constituida por 70 m2. Se utilizó un diseño de bloques completos al azar con una factorial 2x3 con cuatro repeticiones; se emplearon las siguientes densidades de siembra 816 (3,5 x 3,5 m), 952 (3,5 x 3 m) y 1111 (3 x 3 m) plantas ha-1. La variedad Tangongón alcanzó los mejores resultados en altura de planta con 417,72 cm, diámetro del pseudotallo con 20,17 cm y 8,64 hojas por planta; y la variedad Bungalanón obtuvo el mayor número de hijuelos con 19,53. La Tangongón presentó el mayor rendimiento de fibra seca con 1,27 kg, con el mayor peso del pseudotallo (40,73 kg) y tuxeado (18,56 kg). Se desperdició el 96,41% en el proceso de obtención de fibra y solo el 3,59% es lo que se comercializa como fibra, obteniéndose el 30% como fibra de segunda categoría

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Polimorfismo e expressão de genes candidatos e suas relações com o crescimento e as características da carne em bovinos nelore (Bos indicus)

Com o intuito de estudar o potencial de aplicação de genes candidatos na seleção animal para o melhoramento genético da qualidade de carne de bovinos Nelore (Bos indicus), o presente trabalho teve como objetivos principais: (1) Avaliar em bovinos Nelore e cruzamentos Nelore x Bos taurus a ocorrência de associações entre o SNP g.98535683A>G:BTAU7 do gene CAST e as características da carne produzida e (2) quantificar a expressão gênica e proteica da cadeia pesada da miosina em bovinos Nelore com características fenotípicas contrastantes de crescimento e maciez da carne. Para o desenvolvimento do primeiro objetivo, 500 animais foram genotipados para o SNP g.98535683A>G:BTAU7 e fenotipados para força de cisalhamento (FC), índice de fragmentação miofibrilar (MFI), área de olho de lombo (AOL), espessura de gordura subcutânea (EGS) e lipídeos totais (LIP). Associação significativa entre o SNP e a maciez da carne foi observada. O genótipo AA apresentou os melhores valores em relação a esta característica. As diferenças encontradas entre os genótipos AA e AG (AA - AG) foram de - 0,19 kg e 5,31 para FC e MFI, respectivamente. O SNP não mostrou associação significativa com AOL, EGS e LIP. Para a execução do segundo objetivo, 90 bovinos Nelore terminados em confinamento foram utilizados. Levando em consideração o peso final ao abate (PF) e a FC dos 90 animais, 24 indivíduos com características contrastantes de peso e maciez da carne foram selecionados e divididos em quatro grupos experimentais (6 animais/grupo). Os grupos corresponderam a animais leves com carne macia (PF = 493,50 kg e FC = 3,76 kg), animais leves com carne dura (PF = 515,66 kg e FC = 8,06 kg), animais pesados com carne macia (PF = 604,33 kg e FC = 3,99) e animais pesados com carne dura (PF = 605,33 kg e FC = 7,83 kg). Em cada grupo, foram avaliadas características fenotípicas como MFI, AOL, EGS, LIP, índice de marmorização (IM), coloração instrumental (L*, a*, b*) e perdas por cozimento (PT). A análise de expressão dos genes MYH7, MYH2 e MYH1 foi feita por PCR em tempo real (RT-qPCR). A caracterização e quantificação proteica das isoformas da MyHC (MyHC-I, MyHC-IIa e MyHC-IIx/d) foi realizada por eletroforese SDS-PAGE. Em todas as análises (qualidade da carne e expressão gênica e proteica) não foi observada interação significativa entre crescimento e maciez da carne. Nas características AOL, EGS, IM e LIP não foi observado efeito significativo do crescimento e a maciez da carne. Porém, os animais pesados apresentaram maiores valores de L*, a* e b* em relação aos animais leves. Na maciez, o grupo de carne macia mostrou maiores valores de L* (32,29 ± 2,78) que o grupo de carne dura (29,10 ± 2,61). Por outro lado, maiores PT foram observadas em animais com carne dura em relação a animais com carne macia. Nos resultados de expressão gênica, o gene MYH7 não mostrou diferenças entre animais leves e pesados. Entretanto, a expressão dos genes MYH2 e MYH1 foi significativamente menor nos animais pesados em relação aos animais leves. Quanto à maciez da carne, a expressão dos três genes não diferiram significativamente entre grupos de carne dura e macia. Na expressão proteica, as três isoformas (MyHC-I, IIa e IIx), não mostraram diferença significativa entre animais leves e pesados. No entanto, as proporções da MyHC-I foram significativamente maiores no grupo de carne dura (16,51 ± 5,47) em relação ao grupo de carne macia (9,12 ± 3,16) e pelo contrário, as proporções da MyHC-IIa foram maiores no grupo de carne macia (73,78 ± 4,45) em relação ao grupo de carne dura (65,45 ± 8,79). A isoforma MyHC-IIx/d não mostrou efeito significativo sobre a maciez. Os resultados deste trabalho mostraram o potencial de aplicação do SNP g.98535683A>G:BTAU7 do gene CAST e da isoforma MyHC-IIa na seleção de animais para o melhoramento da maciez da carne de bovinos Nelore, além de, manifestar o diferencial de expressão dos genes MYH1 e MYH2 entre animais pesados e leves.In order to study the potential of application of candidate genes in animal selection for breeding meat of Nellore cattle, this work had as main objectives: (1) Assess in Nellore cattle (Bos indicus) and crosses Nellore x Bos taurus the occurrence of associations between the g.98535683A>G:BTAU7 SNP in the CAST gene and traits of the meat produced and (2) quantify the gene and protein expression of myosin heavy chain in Nellore cattle with contrasting phenotypic traits of growth and meat tenderness. For the development of first objective, 500 animals were genotyped for the g.98535683A>G:BTAU7 SNP and phenotyped for shear force (SF), myofibrillar fragmentation index (MFI), ribeye area (RA), backfat thickness (BT) and total lipids (TL). Significant association between the SNP and meat tenderness was observed. The AA genotype showed the best values in relation to this trait. The differences found between genotypes AA and AG (AA - AG) were – 0.19 kg and 5.31 for SF and MFI, respectively. The SNP did not show significant association with RA, BT and TL. For the execution of the second aim, 90 feedlot Nellore cattle were used. Considering the final slaughter weight (FW) and the SF of the 90 animals, 24 individuals with contrasting characteristics of weight and tenderness of meat were selected and divided into four experimental groups (6 animals / group). The groups corresponded to lightweight animals with tender meat (FW = 493.50 kg and SF = 3.76 kg), lightweight animals with tough meat (FW = 515.66 kg and SF = 8.06 kg), heavy animals with tender meat (FW = 604.33 kg and SF = 3.99) and heavy animals with tough meat (FW = 605.33 kg and SF = 7.83 kg). In each group, were evaluated phenotypic characteristics as MFI, RA, BT, TL, marbling índex (MI), instrumental color (L*, a*, b*) and cooking losses (CL). The expression analysis of the MYH7, MYH2 and MYH1 genes was performed by Real-Time PCR (RT-qPCR). The characterization and quantification of the MyHC isoforms (MyHC-I, MyHC-IIa and MyHC-IIx/d) was carried out by SDS-PAGE. In all analyzes (meat quality and gene and protein expression) there was no significant interaction between growth and meat tenderness. In the traits MFI, RA, BT, IM and TL it was not observed significant effect of the growth and the tenderness of meat. However, the heavy animals showed higher values of L*, a* and b* than lightweight animals. In the tenderness, the tender meat group showed higher values of the L* (32.29 ± 2.78) than the tough meat group (29.10 ± 2.61). On the other hand, higher CL were observed in animals with tough meat than animals with tender meat. In the results of gene expression, the MYH7 gene did not show differences between lightweight and heavy animals. However, the expression of the MYH2 and MYH1 genes was significantly lower in heavy animals than lightweight animals. As for meat tenderness, the expression of the three genes did not differ significantly between tough and tender meat groups. In the protein expression, the three isoforms (MHC-I, IIa and IIx), did not show significant difference between lightweight and heavy animals. Nevertheless, the MyHC-I proportions were significantly higher in the tough meat group (16.51 ± 5.47) than tender meat group (9.12 ± 3.16) and on the contrary, the proportions of the MyHC-IIa were higher in tender meat group (73.78 ± 4.45) than tough meat group (65.45 ± 8.79). The MyHC-IIx isoform did not show significant effect on tenderness meat. The results of this work showed the potential of application of the g.98535683A>G:BTAU7 SNP in gene CAST and the MyHC-IIa isoform in animal selection to improve meat tenderness of Nellore cattle, in addition, it showed the differential expression of MYH1 and MYH2 genes between heavy and lightweight animals

Actividad antimicrobiana de weissella confusa y sus metabolitos frente a escherichia coli y klebsiella pneumoniae

Título en ingles: Antimicrobial activity of Weissella confuse and its metabolites against Escherichia coli and  Klebsiella pneumoniaeResumen: Con el fin evaluar el campo de aplicación potencial de una bacteria ácido láctica y de sus metabolitos, se realizó la cinética de la actividad antimicrobiana de W. confusa y de sus  metabolitos contra E. coli, y K. pneumoniae, dos patógenos causantes de enfermedades transmitidas por alimentos. La producción de W. confusa se realizó por fermentación discontinua en sustrato comercial MRS. Se realizaron tres fermentaciones durante 6 horas, sin aireación, agitación continúa 33°C y 100 rpm. Cada hora de fermentación se separaron tres sustancias biológicas, W. confusa con sus metabolitos (W+W10b), células de W. confusa libres de metabolitos (W) y metabolito (W10b) y se midió la actividad antimicrobiana contra los patógenos E. coli, y K. pneumoniae. Se encontraron diferencias estadísticas significativas entre tratamientos y tiempo de fermentación. Para E. coli el tratamiento W presentó la mayor actividad antimicrobiana, la cual se obtuvo entre la cuarta y sexta hora de fermentación (2.45 cm de diámetro promedio de inhibición). Para K. pneumoniae, los tratamientos W y W+W10b presentaron actividad antimicrobiana entre la cuarta y quinta hora de fermentación, sin diferencia significativa entre ellos. W. confusa y el metabolito W10b demostraron poseer capacidad antimicrobiana contra E. coli y K. pneumoniae, lo cual sugiere que W. confusa y W10b podrían utilizarse como alternativa de bioconservación o bioprotección de alimentos frescos y procesados, para alimentación humana y animal; y podría convertirse en una alternativa al uso de antibióticos para enfermedades causadas por E. coli y K. pneumoniae.Palabras clave: bioconservación, alimentos, enfermedades, aplicaciones biotecnológicas.Summary: The kinetic of antimicrobial activity ofWeissella confusa and their metabolites against E. coli, and K. pneumoniae, (two pathogens causing foodborne illness) was evaluated, in order to know the possible use in food processing. W. confusa was produced by batch fermentation using MRS commercial substrate. Three fermentations, of 6 hours at 33 ° C, without aeration, stirring continuously (100 rpm) were performed. In every hour of fermentation, three biological substances, W. confusa with their metabolites (W + W10b), W. confusa free cells metabolites (W), and metabolite (W10b) were separated, and subsequently the antimicrobial activity against pathogenic E. coli and K. pneumoniae was measured. Statistically significant differences between treatments and fermentation time were found. Treatment (W) against E. coli, showed the greatest antimicrobial activity, it was obtained between the fourth and the sixth hours of fermentation (2.45 cm inhibition diameter average). In treatments W and W + W10b against K. pneumoniae, statistically significant differences between them were not found. The antimicrobial activity was shown between the fourth and fifth hour of fermentation. W. confusa and W10b have antimicrobial activity against E. coli andK. pneumoniae, suggesting that W and W10b could be used as an alternative to biopreservation or bioprotection of fresh and processed food for human and animal consumption, and could become an alternative to antibiotics used for diseases caused by E. coli and K. pneumoniae.Key words: bioconservation, food, diseases, biotechnology applications

SARS-CoV-2 y sistema inmune: una batalla de titanes

Humankind is currently facing a challenge that distinguishes no borders, ideologies, socioeconomic systems, ethnic groups, religions or cultures. It is a war that unites us as a biological species, in which the main weapons come from research aimed at improving health systems. In this war, governments and international health organizations define the strategy; and health systems and law enforcement agencies, together with citizens’ support, carry out actions and fight the battles. However, the most important battle is fought inside each of us. Just like Perseus fought against Hades in a battle of titans to prevent the Earth from turning into hell, the immune system activates a powerful machinery in which molecules and cells of the innate and acquired immune system jointly act to defeat SARS-Cov-2: a machinery that follows a script written by evolution, and that will leave in our immune system a memory that will strengthen us as a species to face future Hades. This work summarizes valuable information published in recent months regarding the interaction between SARS-Cov-2 and the immune system. It also includes aspects related to the detection of the immune response as a tool for the diagnosis of this infection, as well as the manipulation of the immune system to prevent or treat the disease.La humanidad se enfrenta, en la actualidad, a un reto que no diferencia fronteras, ideologías, sistemas socioeconómicos, etnias, religiones o culturas. Es una guerra que nos une como especie biológica, en la que las armas fundamentales provienen de la investigación puesta al servicio de los sistemas de salud. En esta guerra los gobiernos y las organizaciones internacionales de salud definen la estrategia; mientras que los sistemas de salud y las fuerzas del orden, de la mano de la ciudadanía, concretan las acciones y libran cada una de las batallas. Sin embargo, el más importante de los enfrentamientos se realiza en el interior de cada uno de nosotros. Como Perseo enfrentó a Hades en una batalla de titanes para evitar que convirtiera la Tierra en un infierno, el sistema inmune pone en marcha una poderosa maquinaria en la que moléculas y células del sistema innato y adquirido actúan de manera coordinada para combatir al SARS-CoV-2. Una maquinaria que sigue un guion escrito por la evolución, y que deja en nuestro sistema de defensa una memoria que nos fortalecerá como especie para enfrentar futuros Hades. Este trabajo resume la valiosa información que se ha publicado en los últimos meses respecto al coronavirus SARS-CoV-2 en su interacción con el sistema inmune. Se incluyen aspectos relacionados con la detección de la respuesta inmune como herramienta para el diagnóstico de esta infección, y la manipulación del sistema inmune en la prevención o el tratamiento de la misma

Pruebas diagnósticas para la COVID-19: la importancia del antes y el después

En 2019, en la cuidad de Wuhan, China, se detectaron pacientes infectados con un nuevo coronavirus denominado 2019-nCoV, hoy SARS-CoV-2. El alarmante crecimiento de esta pandemia hace necesario conocer e implementar métodos de diagnóstico confiables para detectar y tratar adecuadamente a los pacientes, lo que contribuirá a frenar la propagación de la enfermedad. La necesidad de tener profesionales entrenados en la toma de muestras, en las buenas prácticas de laboratorio clínico y en el manejo de técnicas moleculares y hematológicas es de suma importancia para identificar adecuadamente la infección con este virus. La estandarización de los protocolos de obtención, traslado y almacenamiento de la muestra es igualmente relevante para detener la expansión de la pandemia de COVID-19 causada por el SARS-CoV-2.In 2019, in the city of Wuhan, China, patients were diagnosed with a novel coronavirus originally named 2019-nCoV, currently known as SARS-CoV-2. The alarming expansion of this pandemic makes it necessary to find out and implement reliable diagnostic methods in order to properly detect and treat patients, thus contributing to slowing down the spread of the disease. It is extremely important to have trained professionals in sample collection, good clinical laboratory practices, and molecular and hematological techniques to adequately detect any cases of infection with this virus. Moreover, standardized protocols are essential for obtaining, transferring and storing samples to stop the spread of the COVID-19 pandemic caused by SARS-CoV-2

Un nuevo coronavirus, una nueva enfermedad: COVID-19

The novel COVID-19 pandemic caused by the SARS-CoV-2 virus is currently challenging humankind. This virus originated in bats has probably been transmitted to humans through pangolins in the Wuhan marine market (China) by the end of 2019. It is spread by droplets of saliva or through contaminated materials, making it extremely important to isolate infected people who may be symptomatic or asymptomatic. The typical clinical features of this disease are fever, dry cough, shortness of breath and general malaise. This member of the coronavirus family shows higher infectivity but lower mortality rates (2–3 %) than its predecessors. Laboratory tests to detect the virus include reverse transcriptasepolymerase chain reaction (RT-PCR) tests or immunoassays.La nueva pandemia de COVID-19 causada por el virus SARS-CoV-2 desafía actualmente a la humanidad. Este virus originario de murciélagos ha sido transmitido a humanos, probablemente, a través del pangolín en el mercado marino de Wuhan (China) a fines del 2019. Se disemina por gotitas de saliva o a través de materiales contaminados, por lo que es sumamente importante aislar a las personas infectadas que pueden ser sintomáticas o asintomáticas. El cuadro clínico típico se caracteriza por fiebre, tos seca, dificultad respiratoria y malestar general. Este integrante de la familia de los coronavirus tiene mayor capacidad infectiva que sus predecesores, pero una menor mortalidad (2-3 %). Las pruebas de laboratorio para detectar la presencia del virus se basan en la reacción en cadena de la polimerasa con transcriptasa inversa (RT-PCR, por su sigla en inglés) o en inmunoensayos