La actividad peroxidasa en caña de azúcar (Saccharum spp): evolución temporal de la reacción y su posible rol en la resistencia a la roya marrón (Puccinia melanocephala, H&P

La roya marrón de la caña de azúcar, causada por Puccinia melanocephala, es una enfermedad foliar de preocupación en casi todos los países donde se cultiva la caña de azúcar. Los programas de mejoramiento del cultivo se encuentran en la búsqueda de fuentes de resistencia de la planta al patógeno

Analysis of nifH-RNA reveals phylotypes related to Geobacter and Cyanobacteria as important functional components of the N₂-fixing community depending on depth and agricultural use of soil

In this survey, a total of 80 787 reads and 28 171 unique NifH protein sequences were retrieved from soil RNA. This dataset extends our knowledge about the structure and diversity of the functional diazotrophic communities in agricultural soils from Argentinean Pampas. Operational taxonomic unit (OTU)-based analyses showed that nifH phylotypes related to Geobacter and Anaeromyxobacter (44.8%), Rhizobiales (29%), Cyanobacteria (16.7%), and Verrucomicrobiales (8%) are key microbial components of N2 fixation in soils associated with no-till management and soil depth. In addition, quantification of nifH gene copies related to Geobacter and Cyanobacteria revealed that these groups are abundant in soils under maize–soybean rotation and soybean monoculture, respectively. The correlation of physicochemical soil parameters with the diazotrophic diversity and composition showed that soil stability and organic carbon might contribute to the functional signatures of particular nifH phylotypes in fields under no-till management. Because crop production relies on soil-borne microorganism's activities, such as free N2 fixation, the information provided by our study on the diazotrophic population dynamics, associated with the edaphic properties and land-use practices, represents a major contribution to gain insight into soil biology, in which functionally active components are identified.Instituto de Biotecnologia y Biologia Molecula

The impact of COVID-19 pandemic on pornography habits: a global analysis of Google Trends

As the COVID-19 spread globally, social distancing, self-isolation/quarantine, and national lockdowns have become crucial to control the pandemic. However, these measures may also lead to increases in social isolation, loneliness, and stress, which can alter the consumption of pornography habits. The aim of the study was thus to explore the interest pattern in pornography and coronavirus-themed pornography during the COVID-19 outbreak. Google Trends\uae was employed to determine the most popular porn websites (Porn, XNXX, PornHub, xVideos, and xHamster), and coronavirus-themed pornography worldwide and in six nations with different COVID-19 outbreak and self-isolation recommendations. We analyzed every search trend on Google\uae from January 9, 2020 to May 25, 2020 using \u201cjoint point regression analysis\u201d. Comparisons of week relative search volume (WRSV) and temporal patterns were analyzed to assess the change of interest in search terms during nations lockdowns. Paired t-test was used to compare WRSV values among the porn websites during the national lockdowns and the equivalent timespan of the weeks in the previous 4 years. The research trend of almost every keyword increased with significant inflection points for those nations with a straight \u201cstay at home orders\u201d (China, Italy, Spain, and France). \u201cPornHub\u201d and \u201cPorn\u201d showed the highest increase of interest worldwide with an average weekend percentage change (AWPC) of 4.9 and 3.8, respectively. The mean WRSV for keywords in USA and Sweden did not show a similar increase as the other nations. The WRSV percentage change with the historical data had a peak during the straight nations\u2019 lockdowns (p < 0.01). All the nations had a significant increase in WRSV coronavirus-themed pornography for each keyword (p < 0.01) with an AWPC, ranging worldwide between 18.5 and 61.8 (p < 0.01), after the beginning of self-quarantine. As strengths this study uses a big data technology to collect worldwide trend of interest, however, data are anonymous and do not allow analysis of subpopulation groups. In conclusion, we demonstrated an increased interest in pornography and coronavirus-themed pornography after the outbreak of COVID-19 in nations with a straight \u201cstay at home orders\u201d

Analysis of nifH-RNA reveals phylotypes related to Geobacter and Cyanobacteria as important functional components of the N₂-fixing community depending on depth and agricultural use of soil

In this survey, a total of 80 787 reads and 28 171 unique NifH protein sequences were retrieved from soil RNA. This dataset extends our knowledge about the structure and diversity of the functional diazotrophic communities in agricultural soils from Argentinean Pampas. Operational taxonomic unit (OTU)-based analyses showed that nifH phylotypes related to Geobacter and Anaeromyxobacter (44.8%), Rhizobiales (29%), Cyanobacteria (16.7%), and Verrucomicrobiales (8%) are key microbial components of N2 fixation in soils associated with no-till management and soil depth. In addition, quantification of nifH gene copies related to Geobacter and Cyanobacteria revealed that these groups are abundant in soils under maize–soybean rotation and soybean monoculture, respectively. The correlation of physicochemical soil parameters with the diazotrophic diversity and composition showed that soil stability and organic carbon might contribute to the functional signatures of particular nifH phylotypes in fields under no-till management. Because crop production relies on soil-borne microorganism's activities, such as free N2 fixation, the information provided by our study on the diazotrophic population dynamics, associated with the edaphic properties and land-use practices, represents a major contribution to gain insight into soil biology, in which functionally active components are identified.Instituto de Biotecnologia y Biologia Molecula

Dynamics of Seed-Borne Rice Endophytes on Early Plant Growth Stages

Bacterial endophytes are ubiquitous to virtually all terrestrial plants. With the increasing appreciation of studies that unravel the mutualistic interactions between plant and microbes, we increasingly value the beneficial functions of endophytes that improve plant growth and development. However, still little is known on the source of established endophytes as well as on how plants select specific microbial communities to establish associations. Here, we used cultivation-dependent and -independent approaches to assess the endophytic bacterrial community of surface-sterilized rice seeds, encompassing two consecutive rice generations. We isolated members of nine bacterial genera. In particular, organisms affiliated with Stenotrophomonas maltophilia and Ochrobactrum spp. were isolated from both seed generations. PCR-based denaturing gradient gel electrophoresis (PCR-DGGE) of seed-extracted DNA revealed that approximately 45% of the bacterial community from the first seed generation was found in the second generation as well. In addition, we set up a greenhouse experiment to investigate abiotic and biotic factors influencing the endophytic bacterial community structure. PCR-DGGE profiles performed with DNA extracted from different plant parts showed that soil type is a major effector of the bacterial endophytes. Rice plants cultivated in neutral-pH soil favoured the growth of seed-borne Pseudomonas oryzihabitans and Rhizobium radiobacter, whereas Enterobacter-like and Dyella ginsengisoli were dominant in plants cultivated in low-pH soil. The seed-borne Stenotrophomonas maltophilia was the only conspicuous bacterial endophyte found in plants cultivated in both soils. Several members of the endophytic community originating from seeds were observed in the rhizosphere and surrounding soils. Their impact on the soil community is further discussed

Heredabilidad de la resistencia a la roya común (Puccinia melanocephala H. et P. Sydow) en familias FS de caña de azúcar (Saccharum spp)

La caña de azúcar es una especie cultivada de gran complejidad genética. Se postula que la resistencia a la roya común (Puccinia melanocephala H. et P. Sydow) tendría base poligénica u oligogénica con efectos principalmente aditivos y de interacción génica. El empleo de variedades resistentes es el método de control más eficaz, por lo que resulta importante investigar el mecanismo genético que determina la expresión de este atributo. La finalidad de este trabajo fue estimar en poblaciones híbridas la heredabilidad de la resistencia a la roya común, como la regresión de las medias de las progenies sobre las medias de los padres. En la localidad de Barro Negro (Ingenio Río Grande, Jujuy) se investigaron durante tres años consecutivos ocho familias FS BIP (biparentales), involucrando 11 progenitores con diferentes expresiones de resistencia a la enfermedad. La regresión conjunta a través de años permitió estimar una h2= 0,66 (determinación 48%), con valores de 0,90, 0,85 y 0,33 para los años 1, 2 y 3, respectivamente. Las diferencias entre años se explican por la variabilidad de componentes ambientales y probablemente por las cambiantes estructuras poblacionales de P. melanocephala. Los resultados indican la predominancia de efectos genéticos aditivos en la determinación de la resistencia, que explicarían un 92% de la varianza genética total. La heredabilidad es un buen indicador del potencial de los padres para transmitir resistencia a las progenies, lo que permite orientar la selección de combinaciones híbridas que incrementen la frecuencia de aparición de recombinaciones resistentes. Los resultados indican una naturaleza poligénica en la determinación de la resistencia a la roya común en los materiales investigados. Este tipo de resistencia podría complementarse con otros mecanismos de resistencia mediados por genes mayores, contribuyendo a la sostenibilidad de la resistencia

La actividad peroxidasa en caña de azúcar (Saccharum spp): evolución temporal de la reacción y su posible rol en la resistencia a la roya marrón (Puccinia melanocephala, H&P Sydow)

La roya marrón de la caña de azúcar, causada por Puccinia melanocephala, es una enfermedad foliar de preocupación en casi todos los países donde se cultiva la caña de azúcar. Los programas de mejoramiento del cultivo se encuentran en la búsqueda de fuentes de resistencia de la planta al patógeno. Debido a que se demostró que las peroxidasas vegetales participan en la defensa contra los fitopatógenos, el objetivo de este trabajo fue comparar la actividad peroxidasa basal de dos cultivares con respuestas contrastantes a la roya, la evolución de la actividad peroxidasa en el tiempo después de la inoculación con el patógeno y su posible relación con la resistencia o la susceptibilidad de los cultivares de caña de azúcar a la roya. La actividad de la peroxidasa se midió a 24, 48, 72 y 120 horas después de la inoculación. Dos cultivares de caña de azúcar fueron utilizados, R570 (muy resistente) y NA86-2280 (altamente susceptible). La actividad de la peroxidasa aumentó después de la inoculación en ambos cultivares pero aumentó, con mayor velocidad, en R570 hasta alcanzar un máximo a las 48 hs después de la inoculación. La actividad más alta se detectó en R570 durante todo el experimento. Las diferencias en la actividad de la peroxidasa se encontraron entre cultivares y también entre plantas inoculadas y plantas control. Se postula que tanto la actividad basal de la peroxidasa como su incremento después de la inoculación, podrían ser mecanismos complementarios que favorecen la resisten- cia a la roya en la caña de azúcar

Caracterización de accesiones de garbanzo (Cicer arietinum L.) mediante descriptores morfo agronómicos cuantitativos en una colección del Banco de Germoplasma de la Universidad Nacional de Córdoba

El garbanzo (Cicer arietinum L) es la segunda leguminosa más cultivada en el mundo. La producción nacional está basada en pocos cultivares (Norteño, Chañaritos S-156, Kiara UNC-INTA, Felipe UNC-INTA, TUC 403, TUC 464 y TUC G 470). Debido a que el área cultivada está creciendo resulta importante disponer de nuevos materiales genéticos mejor adaptados a diferentes condiciones agroecológicas. Los objetivos del presente trabajo fueron caracterizar diferentes accesiones de garbanzo mediante descriptores morfo agronómicos cuantitativos, evaluar la variabilidad fenotípica de los materiales genéticos, determinar los descriptores que efectivamente contribuyen a la discriminación de las accesiones estudiadas y obtener una función canónica que permita clasificar nuevas accesiones según su origen.Se estudiaron 93 accesiones de garbanzo de diferentes orígenes utilizando diferentes aproximaciones estadísticas uni y multivariadas. La caracterización de las accesiones se realizó sobre cinco plantas, evaluando 17 descriptores morfo agronómicos. Los resultados de los estadísticos simples revelaron que las variables número de vainas por planta y peso de 100 semillas presentaron valores altos de CV. Los componentes de peso y volumen de semillas resultaron asociarse positivamente entre sí, pero negativamente con el número de vainas por planta. En el gráfico del perfil multivariado los caracteres que permitieron la mayor diferenciación de las accesiones fueron número de semillas por planta, número de vainas por planta y rendimiento por planta. En el análisis de conglomerados se dio la conformación de tres grupos diferenciados por las variables pesos de 100 semillas, altura de planta, número de vainas y semillas por planta. En el análisis de componentes principales se encontró que las tres primeras componentes principales explicaron el 66% de la variación total. En el C1 las variables que mayor contribución realizaron a la separación de los tipos de garbanzo fueron: número de vainas y semillas por planta, tamaño de semillas, peso de 100 semillas y altura de planta. Mediante el análisis discriminante se lograron detectar las variables morfo agronómicas que mejor discriminan (número de vainas y semillas por planta) las accesiones. Este estudio permitió concluir que existe una considerable variabilidad en todos los caracteres estudiados. De este modo podría ser utilizada la información para introducir germoplasma con mayor divergencia genética, seleccionando los progenitores con los mayores contrastes genéticos para los programas de mejora y ampliar la base genética para el garbanzo en Argentina

Development Of Scaffold-free Elastic Cartilaginous Constructs With Structural Similarities To Auricular Cartilage

External ear reconstruction with autologous cartilage still remains one of the most difficult problems in the fields of plastic and reconstructive surgery. As the absence of tissue vascularization limits the ability to stimulate new tissue growth, relatively few surgical approaches are currently available (alloplastic implants or sculpted autologous cartilage grafts) to repair or reconstruct the auricle (or pinna) as a result of traumatic loss or congenital absence (e.g., microtia). Alternatively, tissue engineering can offer the potential to grow autogenous cartilage suitable for implantation. While tissue-engineered auricle cartilage constructs can be created, a substantial number of cells are required to generate sufficient quantities of tissue for reconstruction. Similarly, as routine cell expansion can elicit negative effects on chondrocyte function, we have developed an approach to generate large-sized engineered auricle constructs (≥3 cm2) directly from a small population of donor cells (20,000-40,000 cells/construct). Using rabbit donor cells, the developed bioreactor-cultivated constructs adopted structural-like characteristics similar to native auricular cartilage, including the development of distinct cartilaginous and perichondrium-like regions. Both alterations in media composition and seeding density had profound effects on the formation of engineered elastic tissue constructs in terms of cellularity, extracellular matrix accumulation, and tissue structure. Higher seeding densities and media containing sodium bicarbonate produced tissue constructs that were closer to the native tissue in terms of structure and composition. 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J., Puelacher, W.C., Vacanti, C.A., Cartilage engineered in predetermined shapes employing cell transplantation on synthetic biodegradable polymers (1994) Plast Reconstr Surg, 94, p. 233Bichara, D.A., O'Sullivan, N.A., Pomerantseva, I., Zhao, X., Sundback, C.A., Vacanti, J.P., Randolph, M.A., The tissue-engineered auricle: Past, present, and future (2012) Tissue Eng Part B Rev, 18, p. 51Yotsuyanagi, T., Urushidate, S., Watanabe, M., Sawada, Y., Reconstruction of a three-dimensional structure using cartilage regenerated from the perichondrium of rabbits (1999) Plast Reconstr Surg, 103, p. 1120Moskalewski, S., Rybicka, E., The influence of the degree of maturation of donor tissue on the reconstruction of elastic cartilage by isolated chondrocytes (1977) Acta Anat (Basel, 97, p. 231Madsen, K., Moskalewski, S., Mark Von Der, K., Friberg, U., Synthesis of proteoglycans, collagen, and elastin by cultures of rabbit auricular chondrocytes-relation to age of the donor (1983) Dev Biol, 96, p. 63Hellingman, C.A., Verwiel, E.T., Slagt, I., Koevoet, W., Poublon, E.M., Nolst-Trenité, G.J., Baatenburg De Jong, R.J., Van Osch, G.J., Differences in cartilageforming capacity of expanded human chondrocytes from ear and nose and their gene expression profiles (2011) Cell Transplant, 20, p. 925Takebe, T., Kobayashi, S., Kan, H., Suzuki, H., Yabuki, Y., Mizuno, M., Adegawa, T., Taniguchi, H., Human elastic cartilage engineering from cartilage progenitor cells using rotating wall vessel bioreactor (2012) Transplant Proc, 44, p. 1158Duynstee, M.L.G., Verwoerd-Verhoef, H.L., Verwoerd, C.D.A., Van Osch, G.J.V.M., The dual role of perichondrium in cartilage wound healing (2002) Plast Reconstr Surg, 110, p. 1073Skoog, T., Ohlse'n, L., Sohn, S.A., Perichondrial potential for cartilagenous regeneration (1972) Scand J Plast Reconstr Surg, 6, p. 123Togo, T., Utani, A., Naitoh, M., Ohta, M., Tsuji, Y., Morikawa, N., Nakamura, M., Suzuki, S., Identification of cartilage progenitor cells in the adult ear perichondrium: Utilization for cartilage reconstruction (2006) Lab Invest, 86, p. 445Van Osch, G.J., Van Der Veen, S.W., Burger, E.H., Verwoerd-Verhoef, H.L., Chondrogenic potential of in vitro multiplied rabbit perichondrium cells cultured in alginate beads in defined medium (2000) Tissue Eng, 6, p. 321Ruszymah, B.H., Lokman, B.S., Asma, A., Munirah, S., Chua, K., Mazlyzam, A.L., Isa, M.R., Aminuddin, B.S., Pediatric auricular chondrocytes gene expression analysis in monolayer culture and engineered elastic cartilage (2007) Int J Pediatr Otorhinolaryngol, 71, p. 1225Asawa, Y., Ogasawara, T., Takahashi, T., Yamaoka, H., Nishizawa, S., Matsudaira, K., Mori, Y., Hoshi, K., Aptitude of auricular and nasoseptal chondrocytes cultured under a monolayer or three-dimensional condition for cartilage tissue engineering (2009) Tissue Eng Part A, 15, p. 1109Strehl, R., Schumacher, K., De Vries, U., Minuth, W.W., Proliferating cells versus differentiated cells in tissue engineering (2002) 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reconstructed auricles (1978) Plast Reconstr Surg, 61, p. 161Brent, B., Technical advances in ear reconstruction with autogenous rib cartilage grafts: Personal experience with 1200 cases (1999) Plast Reconstr Surg, 104, p. 319Brent, B., Microtia repair with rib cartilage grafts: A review of personal experience with 1000 cases (2002) Clin Plast Surg, 29, p. 257Brenner, J.M., Kunz, M., Tse, M.Y., Winterborn, A., Bardana, D.D., Pang, S.C., Waldman, S.D., Development of large engineered cartilage constructs from a small population of cells (2013) Biotechnol Prog, 29, p. 213Brenner, J.M., Ventura, N.M., Tse, M.Y., Winterborn, A., Bardana, D.D., Pang, S.C., Hurtig, M.B., Waldman, S.D., Implantation of scaffold-free engineered cartilage constructs in a rabbit model for chondral resurfacing (2013) Tissue Eng Regen Med, , DOI: 10.1111/aor.12199Mishell, R.I., Shiigi, J.M., Mishell, B.B., Grabstein, K.H., Shiigi, S.M., Prevention of the immunosuppressive effects of glucocorticosteroids by 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elastic chondrocytes regenerate natural scaffold in vitro and neocartilage with neoperichondrium in the human body post-Transplantation (2012) Tissue Eng Part A, 18, p. 2020Moskalewski, S., Adamiec, I., Golaszewska, A., Maturation of rabbit auricular chondrocytes grown in vitro in monolayer culture (1979) Am J Anat, 155, p. 339Thyberg, J., Hinek, A., Fine structure of rabbit ear chondrocytes in vitro and after autotransplantation (1977) Cell Tissue Res, 180, p. 341Moskalewski, S., Elastic fiber formation in monolayer and organ cultures of chondrocytes isolated from auricular cartilage (1976) Am J Anat, 146, p. 443Moskalewski, S., The elastogenetic process in transplants and cultures of isolated auricular chondrocytes (1981) Connect Tissue Res, 8, p. 171Madsen, K., Von Der Mark, K., Van Menxel, M., Friberg, U., Analysis of collagen types synthesized by rabbit ear cartilage chondrocytes in vivo and in vitro (1984) Biochem J, 221, p. 189Pelttari, K., Steck, E., Richter, W., The use of 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Development of Scaffold-Free Elastic Cartilaginous Constructs with Structural Similarities to Auricular Cartilage

External ear reconstruction with autologous cartilage still remains one of the most difficult problems in the fields of plastic and reconstructive surgery. As the absence of tissue vascularization limits the ability to stimulate new tissue growth, relatively few surgical approaches are currently available (alloplastic implants or sculpted autologous cartilage grafts) to repair or reconstruct the auricle (or pinna) as a result of traumatic loss or congenital absence (e.g., microtia). Alternatively, tissue engineering can offer the potential to grow autogenous cartilage suitable for implantation. While tissue-engineered auricle cartilage constructs can be created, a substantial number of cells are required to generate sufficient quantities of tissue for reconstruction. Similarly, as routine cell expansion can elicit negative effects on chondrocyte function, we have developed an approach to generate large-sized engineered auricle constructs (>= 3 cm(2)) directly from a small population of donor cells (20,000-40,000 cells/construct). Using rabbit donor cells, the developed bioreactor-cultivated constructs adopted structural-like characteristics similar to native auricular cartilage, including the development of distinct cartilaginous and perichondrium-like regions. Both alterations in media composition and seeding density had profound effects on the formation of engineered elastic tissue constructs in terms of cellularity, extracellular matrix accumulation, and tissue structure. Higher seeding densities and media containing sodium bicarbonate produced tissue constructs that were closer to the native tissue in terms of structure and composition. Future studies will be aimed at improving the accumulation of specific tissue constituents and determining the clinical effectiveness of this approach using a reconstructive animal model.204179510121026Canadian Institutes of Health Research (CIHR)Foreign AffairsInternational Trade Canada/L'appui d'Affaires etrangeres et Commerce international Canad