Fabian Sierra

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We have previously reported on the identification of T-kininogen (T-KG) as a gene whose expression is increased during senescence in male Sprague-Dawley (S-D) rats. Serum T-KG levels increase 2.5-4 months before the time of death for any given animal, irrespective of the actual age of the animal at the time of this event. Furthermore, dietary restriction(More)
In the rat, kininogens are produced from two distinctly regulated gene families, T- and K-kininogens. We have previously established that T-kininogen (T-KG, thiostatin) gene expression is increased in the liver of old rats, as compared to their younger counterparts. In this report, we have used Northern blot analysis to show that the steady state mRNA(More)
T-kininogen (T-KG) is a precursor of T-kinin, the most abundant kinin in rat serum, and also acts as a strong and specific cysteine proteinase inhibitor. Its expression is strongly induced during aging in rats, and expression of T-KG in Balb/c 3T3 fibroblasts results in inhibition of cell proliferation. However, T-KG is a serum protein produced primarily in(More)
This paper presents a design and implementation of a cyber-physical system (CPS) for neurally controlled artificial legs. The key to the new CPS system is the neural-machine interface (NMI) that uses an embedded computer to collect and interpret electromyographic (EMG) signals from a physical system that is a leg amputee. A new deciphering algorithm,(More)
Mitogen activated protein kinases (MAPK) are activated by a wide variety of signals leading to cell proliferation and differentiation in different cell types. With aging, there is a marked decrease in proliferation of T-lymphocytes in response to a variety of mitogens. Several age-related changes in the activation of MAPK pathways in T-lymphocytes activated(More)
The synthesis of histone proteins in G1 and S phase HeLa S3 cells was examined by two-dimensional electrophoretic fractionation of nuclear and total cellular proteins. Newly synthesized histones were detected only in S phase cells. Histone messenger RNA sequences, as detected by hybridization with cloned human histone genes, were present in the cytoplasm of(More)
We have previously reported an increase in T-kininogen mRNA levels in the liver of ageing Sprague-Dawley rats. T-Kininogen functions both as a precursor to the vasoactive peptide T-kinin, and as a potent and specific inhibitor of cysteine proteinases. Under normal physiological conditions, the majority of cysteine proteinases are found intracellularly and(More)
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