Epilithic diatoms in the Upper Laja River Basin, Guanajuato, Mexico

This study investigates the epilithic diatoms from the Dolores and Laja Rivers, located within the Upper Laja River Basin, Guanajuato, Mexico. The samples were collected during the cold-dry (January) and rainy (October) seasons of 2011. One-hundred seventy three infrageneric taxa were identified, 7 of which are new records for Mexico: Fallacia monoculata, Hantzschia abundans, Navigiolum uruguayense, Neidium bisulcatum, Nitzschia solita, Planothidium incuriatum and Sellaphora bacilloides; it is worth mentioning that Navigiolum is a new record at the genus level. Furthermore, 3 species are new records for the state of Guanajuato: Gomphonema laticollum, G. subclavatum and Gomphosphenia lingulatiformis. Teratological forms of 6 species were also found in the sampling sites with higher nutrient concentrations, with relative abundances varying from 0.8 to 8.3%

Bioacumulación de cianotoxinas en ecosistemas dulceacuícolas en América Latina: una revisión

Background: The increasing evidence of risk to the environment and human health by cyanotoxin exposure during cyanobacterial blooms has been reported worldwide. Despite the knowledge of cyanotoxin presence in Latin America, cyanotoxin bioaccumulation from freshwater environments have not been reviewed for the region. Goals: To review the current knowledge of cyanotoxin accumulation in tissues of freshwater organisms in field studies in Latin America. Methods: An extensive literature search was conducted to construct a database including information on accumulation of cyanotoxins in organisms inhabiting freshwater environments in Latin America (i.e., México to Argentina). Results: We found twenty-one studies from 2001 to 2020, including twenty-seven mostly eutrophic water bodies, the majority from Brazil. Microcystis was the most reported genus responsible for cyanotoxin production. Fish comprised most of the species accumulating cyanotoxins (20 species). Nile tilapia (Oreochromis niloticus) was the most studied species, and 80% of the fish species included have commercial importance, which highlights a potential route of exposure to humans by consumption of contaminated food. Some studies showed the reduction of cyanotoxins in tissues after an experimental depuration time. Also, calculations of the potential human intakes of microcystins by fish consumption exceeded the recommendations of tolerable intakes in most of the cases. Conclusions: In Latin America, the geographic extent of studies is narrow, however the summarized information indicates a risk for environment and human health by cyanotoxins bioaccumulation. There is a need for more efforts to generate scientific research on cyanotoxins bioaccumulation, but also for improvement of local level management policies to reduce eutrophication.Antecedentes: La creciente evidencia de riesgo para el medio ambiente y la salud humana por la exposición a cianotoxinas durante las floraciones de cianobacterias se ha reportado en todo el mundo. A pesar del conocimiento de la presencia de cianotoxinas en América Latina, la bioacumulación de cianotoxinas en ambientes de agua dulce no ha sido revisada para la región. Objetivos: Revisar el conocimiento actual sobre la acumulación de cianotoxinas en tejidos de organismos de agua dulce en estudios de campo en América Latina. Métodos: Se realizó una extensa búsqueda bibliográfica para construir una base de datos que incluyera información sobre la acumulación de cianotoxinas en organismos que habitan ambientes de agua dulce en América Latina (de México a Argentina). Resultados: Encontramos veintiún estudios de 2001 a 2020, incluidos veintisiete cuerpos de agua en su mayoría eutróficos, la mayoría de Brasil. Microcystis fue el género productor de cianotoxinas más reportado. Los peces comprendieron la mayoría de las especies que acumulaban cianotoxinas (20 especies). Oreochromis niloticus fue la especie más estudiada, y el 80% de las especies de peces incluidas tienen importancia comercial, lo que destaca una vía potencial de exposición a los humanos. Algunos estudios demostraron la reducción de cianotoxinas en los tejidos después de un tiempo de depuración experimental. Además, los cálculos de las ingestas humanas potenciales de microcistinas por consumo de pescado excedieron las recomendaciones de ingestas tolerables en la mayoría de los casos. Conclusiones: En América Latina, los estudios se han realizado en pocos países, sin embargo, estos trabajos indican un riesgo para el medio ambiente y la salud humana por la bioacumulación de cianotoxinas. Se necesita más investigación científica sobre la bioacumulación de cianotoxinas, pero también esfuerzos para mejorar la gestión a nivel local con la finalidad de reducir la eutrofización

Diatomeas epilíticas como indicadores de la calidad del agua en la cuenca alta del río Lerma, México

The upper Lerma River is the most economically important basin of Mexico because it is the region where 80 % of the commercial activity of the country takes place, with 3500 industries, 750,000 Ha of irrigated land and 14 cities with populations over 100,000 inhabitants. Despite this relevance, little or no waste water treatment is done in the basin, which results in high contamination levels. The present paper deals with the taxonomy and ecology of epilithic diatoms collected at 11 sites in the basin in the dry and post-rainy seasons of the 2003-2005 period. This is the first study in an environmental direction of the diatoms of the upper Lerma River basin and the information generated will be used to propose, in the short-term, a Lerma River diatom index (IDL), supporting water quality monitoring programs. 178 taxa were recognized, of which 112 taxa (63%) were cosmopolitan or widely distributed. The genera with most species were Nitzschia (34), Navicula (19), Gomphonema (15), and Pinnularia (11). The dominant species in the studied locations and study period were Eolimna subminuscula (Manguin) Moser, Lange-Bertalot et Metzeltin, Gomphonema parvulum (Kützing) Kützing, Navicula veneta Kützing, Nitzschia capitellata Hustedt, N. sublinearis Hustedt, N. umbonata (Ehrenberg) Lange-Bertalot and Sellaphora pupula (Kützing) Mereschkowsky, which are characterized as tolerant to α-mesosaprobic to polysaprobic conditions, and to high nitrogen content. Trends in distribution of diatom species in the sampling sites were explained by variations in environmental parameters such as depth, conductivity, pH, temperature, and total dissolved solids.La cuenca alta del río Lerma es la más importante de México desde el punto de vista económico, ya que en ella ocurren el 80 % de las actividades comerciales del país, con 3500 industrias diversas, 750,000 hectáreas de tierras de riego y 14 ciudades con poblaciones de más de 100,000 habitantes. El escaso o nulo tratamiento de las aguas residuales, trae como consecuencia una elevada contaminación. Este trabajo abordó el estudio taxonómico y ecológico de diatomeas epilíticas colectadas en 11 localidades de ésta cuenca, entre los años 2003-2005. Se trata del primer estudio con una orientación ambiental que se realiza sobre diatomeas de la cuenca alta de este río, y la información generada permitirá proponer en el corto plazo un índice diatomológico para el Río Lerma (IDL), que posibilite emprender programas de monitoreo de la calidad del agua. Se reconocieron 178 especies, de las cuales 112 taxones (63 %) fueron de amplia distribución. Los géneros con mayor número de especies fueron Nitzschia (34), Navicula (19), Gomphonema (15) y Pinnularia (11). Las especies dominantes en las localidades de estudio y en las épocas de recolecta fueron Eolimna subminuscula (Manguin) Moser, Lange-Bertalot et Metzeltin, Gomphonema parvulum (Kützing) Kützing, Navicula veneta Kützing, Nitzschia capitellata Hustedt, N. sublinearis Hustedt, N. umbonata (Ehrenberg) Lange-Bertalot y Sellaphora pupula (Kützing) Mereschkowsky, que se caracterizan por ser tolerantes a condiciones α-mesosapróbicas a polisapróbicas con alto contenido de nitrógeno. La distribución de las especies de diatomeas fueron explicadas por las variaciones en parámetros como profundidad, conductividad, pH, temperatura y sólidos disueltos totales.Fil: Garcia Segura, Virginia. Universidad Michoacana de San Nicolas de Hidalgo; MéxicoFil: Cantoral Uriza, Enrique A.. Universidad Nacional Autonoma de Mexico. Facultad de Ciencias; MéxicoFil: Israde, Isabel. Universidad Michoacana de San Nicolas de Hidalgo; MéxicoFil: Maidana, Nora Irene. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Diatomeas epilíticas como indicadores de la calidad del agua en la cuenca alta del río Lerma, México

The upper Lerma River is the most economically important basin of Mexico because it is the region where 80 % of the commercial activity of the country takes place, with 3500 industries, 750,000 Ha of irrigated land and 14 cities with populations over 100,000 inhabitants. Despite this relevance, little or no waste water treatment is done in the basin, which results in high contamination levels. The present paper deals with the taxonomy and ecology of epilithic diatoms collected at 11 sites in the basin in the dry and post-rainy seasons of the 2003-2005 period. This is the first study in an environmental direction of the diatoms of the upper Lerma River basin and the information generated will be used to propose, in the short-term, a Lerma River diatom index (IDL), supporting water quality monitoring programs. 178 taxa were recognized, of which 112 taxa (63%) were cosmopolitan or widely distributed. The genera with most species were Nitzschia (34), Navicula (19), Gomphonema (15), and Pinnularia (11). The dominant species in the studied locations and study period were Eolimna subminuscula (Manguin) Moser, Lange-Bertalot et Metzeltin, Gomphonema parvulum (Kützing) Kützing, Navicula veneta Kützing, Nitzschia capitellata Hustedt, N. sublinearis Hustedt, N. umbonata (Ehrenberg) Lange-Bertalot and Sellaphora pupula (Kützing) Mereschkowsky, which are characterized as tolerant to α-mesosaprobic to polysaprobic conditions, and to high nitrogen content. Trends in distribution of diatom species in the sampling sites were explained by variations in environmental parameters such as depth, conductivity, pH, temperature, and total dissolved solids.La cuenca alta del río Lerma es la más importante de México desde el punto de vista económico, ya que en ella ocurren el 80 % de las actividades comerciales del país, con 3500 industrias diversas, 750,000 hectáreas de tierras de riego y 14 ciudades con poblaciones de más de 100,000 habitantes. El escaso o nulo tratamiento de las aguas residuales, trae como consecuencia una elevada contaminación. Este trabajo abordó el estudio taxonómico y ecológico de diatomeas epilíticas colectadas en 11 localidades de ésta cuenca, entre los años 2003-2005. Se trata del primer estudio con una orientación ambiental que se realiza sobre diatomeas de la cuenca alta de este río, y la información generada permitirá proponer en el corto plazo un índice diatomológico para el Río Lerma (IDL), que posibilite emprender programas de monitoreo de la calidad del agua. Se reconocieron 178 especies, de las cuales 112 taxones (63 %) fueron de amplia distribución. Los géneros con mayor número de especies fueron Nitzschia (34), Navicula (19), Gomphonema (15) y Pinnularia (11). Las especies dominantes en las localidades de estudio y en las épocas de recolecta fueron Eolimna subminuscula (Manguin) Moser, Lange-Bertalot et Metzeltin, Gomphonema parvulum (Kützing) Kützing, Navicula veneta Kützing, Nitzschia capitellata Hustedt, N. sublinearis Hustedt, N. umbonata (Ehrenberg) Lange-Bertalot y Sellaphora pupula (Kützing) Mereschkowsky, que se caracterizan por ser tolerantes a condiciones α-mesosapróbicas a polisapróbicas con alto contenido de nitrógeno. La distribución de las especies de diatomeas fueron explicadas por las variaciones en parámetros como profundidad, conductividad, pH, temperatura y sólidos disueltos totales.Fil: Garcia Segura, Virginia. Universidad Michoacana de San Nicolas de Hidalgo; MéxicoFil: Cantoral Uriza, Enrique A.. Universidad Nacional Autonoma de Mexico. Facultad de Ciencias; MéxicoFil: Israde, Isabel. Universidad Michoacana de San Nicolas de Hidalgo; MéxicoFil: Maidana, Nora Irene. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

La importancia ecológica de las algas en los ríos

After reviewing several studies, we set out a proposal regarding the structure and function of benthic algae in rivers. We use an approach that considers the ecology of communities, the role of benthic algae in the rivers autochthonous primary productivity and their eco-physiology in the biogeochemical cycles of the water, their energy intake in food webs, the role they play in the hydrological dynamics in lotic environments, and their use as biological indicators. Finally, pharmaceutical and food industry use of the species in these environments is reviewed.A través de una revisión de diversos estudios, se realiza un planteamiento de la estructura y función que tienen las algas bentónicas en los ríos, desde un punto de vista de la ecología de comunidades, la participación que tienen en la productividad primaria autóctona de los ríos y su ecofisiología, en los ciclos biogeoquímicos del agua, su aporte energético en las redes tróficas, la función que tienen en la dinámica hídrica de los ambientes lóticos, su uso como indicadores biológicos y se plantean algunos usos que se han realizado con especies de estos ambientes en la industria farmaceútica y alimenticia

Immune function and dysfunction are determined by lymphoid tissue efficacy

Lymphoid tissue returns to a steady state once each immune response is resolved, and although this occurs multiple times throughout life, its structural integrity and functionality remain unaffected. Stromal cells orchestrate cellular interactions within lymphoid tissue, and any changes to the microenvironment can have detrimental outcomes and drive disease. A breakdown in lymphoid tissue homeostasis can lead to a loss of tissue structure and function that can cause aberrant immune responses. This Review highlights recent advances in our understanding of lymphoid tissue function and remodelling in adaptive immunity and in disease states. We discuss the functional role of lymphoid tissue in disease progression and explore the changes to lymphoid tissue structure and function driven by infection, chronic inflammatory conditions and cancer. Understanding the role of lymphoid tissues in immune responses to a wide range of pathologies allows us to take a fuller systemic view of disease progression

Exposure to Bisphenol A and phthalates metabolites in the third trimester of pregnancy and BMI trajectories

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146291/1/ijpo12279.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146291/2/ijpo12279_am.pd

Epilithic diatoms (Bacillariophyceae) as indicators of water quality in the Upper Lerma River, Mexico

The upper Lerma River is the most economically important basin of Mexico because it is the region where 80 % of the commercial activity of the country takes place, with 3500 industries, 750,000 Ha of irrigated land and 14 cities with populations over 100,000 inhabitants. Despite this relevance, little or no waste water treatment is done in the basin, which results in high contamination levels. The present paper deals with the taxonomy and ecology of epilithic diatoms collected at 11 sites in the basin in the dry and post-rainy seasons of the 2003-2005 period. This is the first study in an environmental direction of the diatoms of the upper Lerma River basin and the information generated will be used to propose, in the short-term, a Lerma River diatom index (IDL), supporting water quality monitoring programs. 178 taxa were recognized, of which 112 taxa (63%) were cosmopolitan or widely distributed. The genera with most species were Nitzschia (34), Navicula (19), Gomphonema (15), and Pinnularia (11). The dominant species in the studied locations and study period were Eolimna subminuscula (Manguin) Moser, Lange-Bertalot et Metzeltin, Gomphonema parvulum (Kützing) Kützing, Navicula veneta Kützing, Nitzschia capitellata Hustedt, N. sublinearis Hustedt, N. umbonata (Ehrenberg) Lange-Bertalot and Sellaphora pupula (Kützing) Mereschkowsky, which are characterized as tolerant to ?-me­so­saprobic to polysaprobic conditions, and to high nitrogen content. Trends in distribution of diatom species in the sampling sites were explained by variations in environmental parameters such as depth, conductivity, pH, temperature, and total dissolved solids

Overweight and obesity status from the prenatal period to adolescence and its association with non- alcoholic fatty liver disease in young adults: cohort study

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/16/bjo16199-sup-0005-ICMJES2.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/15/bjo16199-sup-0012-ICMJES12.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/14/bjo16199_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/13/bjo16199-sup-0010-ICMJES10.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/12/bjo16199-sup-0002-TableS1.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/11/bjo16199.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/10/bjo16199-sup-0007-ICMJES4.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/9/bjo16199-sup-0008-ICMJES5.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/8/bjo16199-sup-0006-ICMJES3.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/7/bjo16199-sup-0003-AppendixS1.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/6/bjo16199-sup-0011-ICMJES11.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/5/bjo16199-sup-0013-ICMJES13.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/4/bjo16199-sup-0014-ICMJES14.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/3/bjo16199-sup-0001-FigS1.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/2/bjo16199-sup-0009-ICMJES6.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156435/1/bjo16199-sup-0004-ICMJES1.pd