V. Pletser¹, R. Bosch², L. Potthast², R. Kassel³

FDMP-Fluid Dynamics & Materials Processing, Vol.2, No.1, pp. 65-76, 2006, DOI:10.3970/fdmp.2006.002.065

Abstract Orbital weightless conditions have been shown to yield better and larger crystals. The Solution Crystallization Diagnostics Facility (SCDF) is a third generation instrument developed by ESA and dedicated to the observation and study with advanced diagnostics nucleation and crystallisation processes of molecules from solutions on board the International Space Station. The SCDF is intended to be used for studies of proteins and large biomolecules, and more generally of any kind of molecules growing from solutions, using the powerful set of diagnostics means available in the SCDF platform. Several protein crystallisation reactors have been developed to More >

ROBERTO YUNES, PEDRO FERNÁNDEZ, GUSTAVO F. DONCEL, ANÍBAL A. ACOSTA

BIOCELL, Vol.29, No.3, pp. 287-293, 2005, DOI:10.32604/biocell.2005.29.287

Abstract Our objective was to determine the effect of phosphodiesterase (PDE) inhibition on: 1) tyrosine phosphorylation of human spermatozoa at the tail level; and 2) sperm motion parameters and hyperactivated motility. The study was conducted with normozoospermic and asthenozoospermic samples incubated under in vitro capacitating conditions. The main outcome measures were computer-assisted sperm motion analysis and fluorescent immunodetection of phosphotyrosine-containing proteins. Pentoxifylline (PTX) was used as PDE inhibitor because of its wide use in the clinic. PTX-treatment significantly increased sperm velocity, hyperactivated motility and tyrosine-phosphorylation, both in normo and asthenozoospermic samples. Tyrosine-phosphorylation of tail proteins was highly More >

Muhammad H. Zaman¹

Molecular & Cellular Biomechanics, Vol.2, No.4, pp. 179-190, 2005, DOI:10.3970/mcb.2005.002.179

Abstract We report the results of longest to date simulation on misfolding of monomeric human prion protein (HuPrP). By comparing our simulation of a partially unfolded protein to the simulation of the native protein, we observe that the native protein as well as native regions in the partially unfolded protein remain in the native state, and the unfolded regions fold back with increased extended (sheet and PP-II) conformations. The misfolded regions show increased basin hopping from non-helical basins while the amino acids locked in the helical conformation tend to stay locked in that conformation. Our results More >

N.I. Wakayama¹, D.C. Yin², J.W. Qi³

FDMP-Fluid Dynamics & Materials Processing, Vol.1, No.2, pp. 153-170, 2005, DOI:10.3970/fdmp.2005.001.153

Abstract The production of crystals of adequate size and high quality is the "bottleneck'' for three-dimensional structure analysis of protein crystals. In this work, in order to shed additional light on the (still controversial) beneficial effect of microgravity on crystal growth, we focus on recent advanced experimental and theoretical research about the effects of buoyancy-driven convection on protein crystallization. In the light of the numerical studies the following major outcomes can be highlighted: (1) when the crystal size exceeds several dozens of µm, buoyancy-driven convection dominates solute transport near the growing crystal and the crystal growth rate… More >

KARINA MANCINI, HEIDI DOLDER

BIOCELL, Vol.28, No.3, pp. 299-310, 2004, DOI:10.32604/biocell.2004.28.299

Abstract This study was undertaken to detect protein components in both sperm types of the butterfly Euptoieta hegesia. These spermatozoa possess complex extracellular structures for which the composition and functional significance are still unclear. In the apyrene sperm head, the proteic cap presented an external ring and an internal dense content; basic proteins were detected only in external portions. In the tail, the paracrystalline core of mitochondrial derivatives and the axoneme are rich in proteins. The extratesticular spermatozoa are covered by a proteic coat, which presented two distinct layers. In eupyrene spermatozoa, acrosome and nucleus were negatively… More >

Min Yue^1,1, Jeanne C. Stachowiak^1,1,2,2, Arunava Majumdar^1,1,3,3

Molecular & Cellular Biomechanics, Vol.1, No.3, pp. 211-220, 2004, DOI:10.3970/mcb.2004.001.211

Abstract Microchips;ontaining arrays of cantilever beams have been used to mechanically detect and quantitatively analyze multiple reactions of DNA hybridization and antigen-antibody binding simultaneously. The reaction-induced deflection of a cantilever beam reflects the interplay between strain energy increase of the beam and the free energy reduction of a reaction, providing an ideal tool for investigating the connection between mechanics and chemistry of biomolecular reactions. Since free energy reduction is common for all reactions, the cantilever array forms a universal platform for label-free detection of various specific biomolecular reactions. A few such reactions and their implications in More >

BIOCELL, Vol.27, Suppl.S, pp. 1-172, 2003

Abstract This article has no abstract. More >

T.L. Rose*, V.M. Gomes*, M. Da Cunha**, K.V.S. Fernandes***, J. Xavier-Filho***

BIOCELL, Vol.27, No.2, pp. 173-179, 2003, DOI:10.32604/biocell.2003.27.173

Abstract Vicilins (7S storage proteins) found in various legume seeds have been previously shown to interfere with the germination of spores or conidia of phytopathogenic fungi and inhibit yeast growth and glucose stimulated acidification of the medium by yeast cells. In the present work vicilins from cowpea (Vigna unguiculata) seeds were added to the growth medium of Saccharomyces cerevisiae cells and Fusarium oxysporum conidia. Helix pomatia lectin, wheat germ agglutinin and Ulex europaeus lectin were used to identify differences in the binding of the vicilins to the surface of cells of S. cerevisiae and F. oxysporum treated with this protein. After the growth More >

R. Yunes, G.F. Doncel, A.A. Acosta

BIOCELL, Vol.27, No.1, pp. 29-36, 2003, DOI:10.32604/biocell.2003.27.029

Abstract Our objective was to study the incidence of sperm-tail phosphotyrosine immunoreactivity in normozoospermic and asthenozoospermic human sperm samples, its association with sperm motion parameters, particularly hyperactivated motility, and its potential involvement in the pathogenesis of asthenozoospermia. The work was conducted as a prospective experimental study in the Sperm Biology and Andrology laboratories of the Jones Institute, a medical school-based fertility center. The study subjects were healthy fertile male donors (normozoospermic samples) and infertile patients (asthenozoospermic samples) attending the center. Recently ejaculated semen samples were washed twice to eliminate seminal plasma and a swim-up was performed… More >

H. Heras, R.J. Pollero

BIOCELL, Vol.26, Suppl.S, pp. 111-118, 2002

Abstract This article has no abstract. More >