Human consumption of sea urchin gonads has led to overexploitation of commercial species, and the search for new marketable species to promote the recovery of exploited populations. Echinometra ...vanbrunti is a promising candidate for commercial exploitation. Its annual reproductive cycle has an effect on the proximate composition of the gonads; if they were to be consumed, the best quality in biochemical composition was determined to be from December to May, when nutritive phagocytes uphold the highest contents of protein and lipid. They possess considerable levels of omega-3 essential fatty acids, predominantly eicosapentaenoic and docosahexaenoic (DHA) acids, quite important for human nutrition. A subtle trend of higher DHA levels during the growing, premature, and mature gonadal stages of females and males was observed, though it is strongly influenced by diet and environment. A program to protect and regulate the sustainable extraction needs to be put in place before commercial exploitation.
The shrimp necrotizing hepatopancreatitis is caused by a pleomorphic Gram-negative Rickettsialike bacteria known as NHP-B. It is well known that silver is an effective bactericidal, but experiments ...with aquatic organisms are scarce, even more at nanoparticle level. The objective of this study was to determine the antibacterial effect of silver nanoparticles (AgNP) against NHP-B in the Pacific white shrimp Litopenaeus vannamei. For this, AgNO.sub.3 was used as source of silver, and extracts of dried leaves of green tea Camellia sinensis and neem tree Azadirachta indica as reducing agents. Different lots of infected shrimp received 0,5 and 35 microg of AgNP by forced feeding. The differences between the number of bacterial nodules in shrimp hepatopancreas and shrimp mortality relative to the amount of AgNP demonstrated to be effective against this pathogen.
The Ostreid herpes virus type 1 (OsHV-1) is one of the most devastating pathogen in oyster cultures. Among several factors, as food limitation, oxygen depletion, salinity and temperature variations, ...episodes of “summer mortality” of the Pacific oyster Crassostrea gigas have also been associated with OsHV-1 infection. Mortalities of C. gigas spat and juveniles have increased significantly in Europe, and contemporary mortality records of this mollusk in México have been associated with the occurrence of OsHV-1. In the present study, the expression of the heat shock protein 70 gene from the Pacific oyster correlates with the abundance of DNA polymerase transcripts from the OsHV-1. This may suggest that the induction on the expression of the Pacific oyster hsp70 may potentially participate in the immune response against the virus. Furthermore, this study reports for the first time a TEM representative image of the OsHV-1 in aqueous solution, which possesses an icosahedral shape with a diameter of 70 nm × 100 nm. Finally, the examined sequence encoding the ORF4 of the OsHV-1 isolate from northwest Mexico showed specific sequence variations when compared with OsHV-1 isolates from distant geographical areas.
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•We studied the effect of OsHV-1 on the expression of C. gigas hsp70.•Hsp70 never returned to it amount of mRNA control organism level.•Hsp70 levels were related to the infection level.•In situ detection of host and pathogen genes in same tissues.•First negative aqueous TEM images of the OsHV-1.
En este trabajo se describe de manera general la importancia de la cristalización de proteínas para realizar experimentos de difracción de rayos X que permitan dilucidar la estructura terciaria de ...dichas biomoléculas. En particular, se expone que la cristalización de proteínas de membrana requiere métodos especiales de preparación de la matriz de cristalización puesto que se debe “mimetizar” el ambiente hidrofóbico de la proteína en la membrana. De esta manera, el trabajo se centra en algunas propiedades de la fase líquida de membranas denominada “fase esponja”, cuya característica principal es una estructura membranar compleja conectada en tres dimensiones. Debido a su microestructura, la fase esponja es transparente e isotrópica, además de presentar baja viscosidad en las membranas. Estas características convierten a la fase esponja en un medio “biomimético” potencialmente útil para cristalizar proteínas de membrana.
MÉTODOS DE SIMULACIÓN COMPUTACIONAL EN BIOLOGÍA Maldonado Arce, Amir Darío; Contreras Aburto, Claudio; Favela Rosales, Fernando ...
Epistemus : ciencia tecnología y salud,
12/2016, Letnik:
10, Številka:
21
Journal Article
Odprti dostop
Las técnicas de simulación computacional se usan extensivamente para estudiar sistemas biológicos, y en general, materiales sólidos y blandos. Debido a la complejidad de los fenómenos biológicos, y a ...la imposibilidad de estudiar teóricamente el comportamiento de sistemas tales como proteínas y membranas, la simulación computacional se utiliza para estudiar la estructura y dinámica de estos sistemas en diferentes escalas temporales. En este artículo describiremos brevemente algunas de las técnicas de simulación computacional más utilizadas en Biología: la Dinámica Molecular, la Dinámica Browniana y el Método de Monte Carlo. Nuestra intención es proporcionar un panorama introductorio de la utilidad de los métodos de simulación molecular en Biología.
The shrimp necrotizing hepatopancreatitis is caused by a pleomorphic Gram-negative Rickettsialike bacteria known as NHP-B. It is well known that silver is an effective bactericidal, but experiments ...with aquatic organisms are scarce, even more at nanoparticle level. The objective of this study was to determine the antibacterial effect of silver nanoparticles (AgNP) against NHP-B in the Pacific white shrimp Litopenaeus vannamei. For this, AgNO.sub.3 was used as source of silver, and extracts of dried leaves of green tea Camellia sinensis and neem tree Azadirachta indica as reducing agents. Different lots of infected shrimp received 0,5 and 35 microg of AgNP by forced feeding. The differences between the number of bacterial nodules in shrimp hepatopancreas and shrimp mortality relative to the amount of AgNP demonstrated to be effective against this pathogen. Keywords: Litopenaeus vannamei, Azadirachta indica, Camellia sinensis, necrotizing hepatopancreatitis bacterium, Pacific white shrimp, silver nanoparticles.
MÉTODOS DE SIMULACIÓN COMPUTACIONAL EN BIOLOGÍA Amir Darío Maldonado Arce; Claudio Contreras Aburto; Fernando Favela Rosales ...
Epistemus : ciencia tecnología y salud,
12/2016, Letnik:
10, Številka:
21
Journal Article
Odprti dostop
Las técnicas de simulación computacional se usan extensivamente para estudiar sistemas biológicos, y en general, materiales sólidos y blandos. Debido a la complejidad de los fenómenos biológicos, y a ...la imposibilidad de estudiar teóricamente el comportamiento de sistemas tales como proteínas y membranas, la simulación computacional se utiliza para estudiar la estructura y dinámica de estos sistemas en diferentes escalas temporales. En este artículo describiremos brevemente algunas de las técnicas de simulación computacional más utilizadas en Biología: la Dinámica Molecular, la Dinámica Browniana y el Método de Monte Carlo. Nuestra intención es proporcionar un panorama introductorio de la utilidad de los métodos de simulación molecular en Biología.
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