Application of exogenous melatonin in vitro and in planta: a review of its effects and mechanisms of action

Biotechnology Letters - Melatonin is a natural indolamine that regulates many physiological functions in plants. The most prominent role of melatonin in plants has been its ability to work as an...     

Destruxin production by the entomogenous fungus <Emphasis Type="Italic">Metarhizium anisopliae</Emphasis> in insects and factors influencing their degradation

There is much public interest in the use of fungal biological control agents as alternatives to chemical pesticides. However, there are some concerns as to whether the metabolites produced by these fungi pose a risk to humans and the environment. Destruxins are the main metabolites produced by the insect pathogenic fungus Metarhizium anisopliae (Metsch.) Sorok. The production of these compounds in two different insect hosts and their subsequent fate in the soil were assessed as a case study. Destruxin profiling revealed that the amount and type of destruxin produced was dependant upon the fungal strain and insect host and that these compounds decomposed shortly after host death. Destruxin decomposition was presumably due to the activity of hydrolytic enzymes in the cadavers and appeared to be independent of host or soil type and biota. Temperature strongly influenced destruxin decomposition. Our studies are the first to show that the destruxins are essentially restricted to the host and pathogen and are unlikely to contaminate the environment or enter the food chain.     

Scaffold architecture determines chondrocyte response to externally applied dynamic compression

It remains unclear how specific mechanical signals generated by applied dynamic compression (DC) regulate chondrocyte biosynthetic activity. It has previously been suggested that DC-induced interstitial fluid flow positively impacts cartilage-specific matrix production. Modifying fluid flow within dynamically compressed hydrogels therefore represents a promising approach to controlling chondrocyte behavior, which could potentially be achieved by changing the construct architecture. The objective of this study was to first determine the influence of construct architecture on the mechanical environment within dynamically compressed agarose hydrogels using finite element (FE) modeling and to then investigate how chondrocytes would respond to this altered environment. To modify construct architecture, an array of channels was introduced into the hydrogels. Increased magnitudes of fluid flow were predicted in the periphery of dynamically compressed solid hydrogels and also around the channels in the dynamically compressed channeled hydrogels. DC was found to significantly increase sGAG synthesis in solid constructs, which could be attributed at least in part to an increase in DNA. DC was also found to preferentially increase collagen accumulation in regions of solid and channeled constructs where FE modeling predicted higher levels of fluid flow, suggesting that this stimulus is important for promoting collagen production by chondrocytes embedded in agarose gels. In conclusion, this study demonstrates how the architecture of cell-seeded scaffolds or hydrogels can be modified to alter the spatial levels of biophysical cues throughout the construct, leading to greater collagen accumulation throughout the engineered tissue rather than preferentially in the construct periphery. This system also provides a novel approach to investigate how chondrocytes respond to altered levels of biophysical stimulation.     

Cadmium in Seminal Plasma of Fertile and Infertile Male Dromedary Camels

Biological Trace Element Research - The objective of this study was to investigate the cadmium (Cd) profile in seminal plasma of male dromedary camel with impotentia generandi (post-coital...     

Fabrication,characterization and application of laccase–nylon 6,6/Fe3+ composite nanofibrous membrane for 3,3′-dimethoxybenzidine detoxification

Bioprocess and Biosystems Engineering - In this study, laccase was immobilized on nylon 6,6/Fe3+ composite (NFC) nanofibrous membrane and used for the detoxification of...     

Community structure of the deep sea fishes in the northern Gulf of Aqaba,Red Sea (Osteichthyes and Chondrichthyes)

The aim of this study was to investigate the community structure of deep sea fishes in the northern Gulf of Aqaba. Deep fish traps, short lines and long lines were deployed at depth ranges from 60 to 700 m between June 2014 and May 2015. A total of 369 fish individuals belonging to 37 species in 21 families were collected. The most abundant family observed in deep fish traps and short line was the commercially important family Sparidae, whereas the most abundant family in long line catch was the commercially unimportant fish family Muraenidae. The most abundant fish species sampled by deep fish traps and shortline was Blueskin Seabream, Polysteganus coeruleopunctatus. The most abundant species in long line catch White-spotted Moray, Gymnothorax johnsoni. In fish traps and with short line, the most commonly caught species was Blueskin Seabream. White-spotted Moray was the most common long line catch. Depth distribution for 37 deep fish species and GIS maps for the two main commercial fish species Blueskin Seabream and Bigeye Hound Shark, Iago omanensis were documented.