Impact of L-carnitine and selenium treatment on testicular apoptosis in rats exposed to 2.45 GHz microwave energy

Objective: It has been suggested that electromagnetic radiation (EMR) by wireless devices (2.45 GHz) induces testicular apoptosis. We investigated if supplemental selenium (Se) and L-carnitine may reduce this adverse effect. Material: Twelve-week old maleWistar albino rats were used in this study. Twenty-four rats were equally divided into four groups which were named as: sham group, EMR-only, EMR+L-carnitine (1.5 mg L-carnitine/ kg/day) and EMR+Se (1.5 mg Se/kg/ every other day). Results: The level of Bcl-2, Bax, caspase-3 and -8 were compared and a significant difference was found between the sham and EMR-only groups (p < 0.05), and Bcl-2, Bax, caspase-3 and -8 expressions increased in the EMR-only group. The level of Bcl-2, Bax, tumour necrosis factor-alpha (TNF-α), caspase- 3 and -8 were compared and a significant difference was found between the sham and EMR+L-carnitine groups (p < 0.05) and Bcl-2, Bax, TNF-α, caspase-3 and -8 expressions increased in the EMR+L-carnitine group. The level of Bcl-2, Bax, TNF-α, caspase-3 and -8 were compared and a significant difference was found between the sham and EMR+Se groups (p < 0.05) and Bcl-2, Bax, TNF-α, caspase-3 and -8 expressions increased in the EMR+Se group. When the expression of caspase-8 was compared, a significant difference was found between the EMR-only and EMR+Se groups (p < 0.05). Caspase-8 expression decreased in EMR+Se group compared with EMR-only group. Conclusion: Electromagnetic radiation exposure resulted in testicular apoptosis in rats, mainly by the intrinsic pathways by down-regulated expression of caspase-8. Reduction in the activation of the intrinsic pathway of apoptosis was found higher with selenium administration compared with L-carnitine administration

On normalized rabotnov function associated with certain subclasses of analytic functions

In this paper, we investigate some sufficient conditions for the normalized Rabotnov function to be in certain subclasses of analytic and univalent functions. The usefulness of the results is depicted by some corollaries and examples

Measurement of ammonia and glutamine in cell culture media by gas sensing electrodes

This paper describes the use of a commercially available off-line gas sensing electrode for determination of ammonia and glutamine in cell culture media. The measurement technique was tested in different media preparations with different serum concentrations. The glutamine decomposition was studied as a function of pH for cell culture medium and the results were compared to those obtained by conventional methods, i.e. , HPLC. Finally, glutamine and ammonia metabolism were studied during the cultivation of a hybridoma cell line.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42489/1/10542_2005_Article_BF01876051.pd

Kinetic characterization of hybridoma growth, metabolism, and monoclonal antibody production rates.

Monoclonal antibodies produced by hybridoma cells are one of the most important products of biotechnology. Optimal design and development of bioreactors require a quantitative understanding of cell growth, metabolism, and antibody production rates. This thesis is a comprehensive investigation of the influence of culture environment on these biological variables. Both the extent of cell growth and the final antibody concentrations were influenced by the inoculum size, but specific growth, metabolic, and antibody production rates were less sensitive to initial cell density. Short-term exposure to new serum concentrations influenced the growth rate in a Michaelian fashion, but did not alter the cell metabolism and antibody production rate. When cells were cultured in low serum-containing media for prolonged periods of time (6 months), they adapted and both growth and antibody titer were improved. However, for one cell line, adaptation to low serum resulted in a gradual loss of antibody productivity. We have determined that this loss is due to the appearance of a sub-population that has lower internal and surface antibody content. Cell growth was inhibited at 100% air saturation and at very low dissolved oxygen concentrations leading to an optimal range between 25 and 50% air saturation. We have also demonstrated that the cells used in this study could grow and produce antibody under total anaerobic conditions, which has important implications for the design of high density cultures. The antibody production rate was unaffected by the dissolved oxygen concentration. Cell growth and antibody production were optimal at pH 7.2 while the specific antibody production rate, though unaltered under alkaline conditions, was 2-3 fold higher under acidic conditions. Elevated media osmolarity also influenced the specific antibody production rate. Both ammonia and lactate inhibit growth, but do not accelerate cell death. Cell metabolism was influenced by lactate and ammonia levels. However, the specific antibody production rate was unaffected. It is hoped that the results presented in this thesis will contribute significantly to a better understanding of cell physiology in bioreactor environments, and provide coherent design principles for the optimization of mammalian cell culture technology.Ph.D.Chemical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/105413/1/9023613.pdfDescription of 9023613.pdf : Restricted to UM users only