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41.
The aim of this study was to detect the effect of extracellular matrix (ECM) proteins on rat Leydig cell shape, adhesion, expression of integrin subunits and testosterone production, in vitro. Leydig cells isolated from adult rats were cultured on plates uncoated or coated with different concentrations of laminin-1, fibronectin, or type IV collagen in the presence or absence of hCG for 3 or 24 hr. A significant increase of cell adhesion and of alpha3, alpha5, and beta1 integrin subunit expression was observed when cells were cultured on ECM proteins, compared to those grown on uncoated plates. Leydig cells cultured on glass coverslips coated with ECM proteins for 24 hr exhibited elongated shapes with long cell processes (spreading), while cells cultured on uncoated plates showed few cell processes. A significant decrease in testosterone production was observed when basal and hCG-stimulated Leydig cells were cultured for 3 or 24 hr on plates coated with type IV collagen (12 and 24 microg/cm(2)) compared to uncoated plates. A significant though a slighter decrease in testosterone production was also observed in cells cultured on plates coated with fibronectin (12 and 24 microg/cm(2)), compared to uncoated plates. Laminin-1 did not modify testosterone production under basal or hCG stimulated conditions. These results suggest that ECM proteins are able to modulate Leydig cell steroidogenesis, in vitro.  相似文献   
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WW domains mediate protein-protein interactions in a number of different cellular functions by recognizing proline-containing peptide sequences. We determined peptide recognition propensities for 42 WW domains using NMR spectroscopy and peptide library screens. As potential ligands, we studied both model peptides and peptides based on naturally occurring sequences, including phosphorylated residues. Thirty-two WW domains were classified into six groups according to detected ligand recognition preferences for binding the motifs PPx(Y/poY), (p/phi)P(p,g)PPpR, (p/phi)PPRgpPp, PPLPp, (p/xi)PPPPP, and (poS/poT)P (motifs according to modified Seefeld Convention 2001). In addition to these distinct binding motifs, group-specific WW domain consensus sequences were identified. For PPxY-recognizing domains, phospho-tyrosine binding was also observed. Based on the sequences of the PPx(Y/poY)-specific group, a profile hidden Markov model was calculated and used to predict PPx(Y/poY)-recognition activity for WW domains, which were not assayed. PPx(Y/poY)-binding was found to be a common property of NEDD4-like ubiquitin ligases.  相似文献   
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Summary Fourteen lysosomal enzymes were compared in 20 cultured cell lines from chorionic biopsy and corresponding embryonic tissue after voluntary abortions. Enzymatic expression appears to be similar in cultured cells from both sources with some slightly higher levels for chorionic villi. We stress the importance of culturing chorionic villi especially in the case of enzymes (-L-iduronidase) or diseases (I cell disease) whose expression is unusual in fresh trophoblast tissue.  相似文献   
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Laccase production in saline conditions is still poorly studied. The aim of the present study was to investigate the production of laccase in two different types of bioreactors by the marine-derived basidiomycete Peniophora sp. CBMAI 1063. The highest laccase activity and productivity were obtained in the Stirred Tank (ST) bioreactor, while the highest biomass concentration in Air-lift (AL) bioreactor. The main laccase produced was purified by ion exchange and size exclusion chromatography and appeared to be monomeric with molecular weight of approximately 55 kDa. The optimum oxidation activity was obtained at pH 5.0. The thermal stability of the enzyme ranged from 30 to 50 °C (120 min). The Far-UV Circular Dichroism revealed the presence of high β-sheet and low α-helical conformation in the protein structure. Additional experiments carried out in flask scale showed that the marine-derived fungus was able to produce laccase only in the presence of artificial seawater and copper sulfate. Results from the present study confirmed the fungal adaptation to marine conditions and its potential for being used in saline environments and/or processes.  相似文献   
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Amyotrophic lateral sclerosis (ALS) is a rapidly progressive and ultimately fatal neurodegenerative disorder of unknown aetiology that involves the loss of upper and lower motor neurons in the cerebral cortex, brainstem and spinal cord. Significant progress in understanding the cellular mechanisms of motor neuron degeneration in ALS has not been matched with the development of therapeutic strategies to prevent disease progression, and riluzole remains the only available therapy, with only marginal effects on disease survival. More recently alterations of mRNA processing in genetically defined forms of ALS, as those related to TDP-43 and FUS-TLS gene mutations have provided important insights into the molecular networks implicated in the disease pathogenesis. Here we review some of the recent progress in promoting therapeutic strategies for neurodegeneration.  相似文献   
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The aim of this study was to investigate the health care available for the poor citizens of Split during the first half of the 19th century. Soon after being constructed in 1797, the Civic Hospital in Split founded by the Ergovac brothers for the needs of the poor was transformed into a military hospital. Consequently, caring for this social stratum was taken over by two inadequate shelters and later by a small civic hospital situated in the Split suburb of Dobri. The year of the application of Petar Ergovac to the supreme ruler for the transformation of the hospital building established by his family from a military to a civil institution was found, as well as the correct data regarding its return to initial idea in 1821. On the basis of the archival documents kept in the Archaeological Museum in Split and in the State Archives in Zadar, the work organization of the Civic Hospital in Split and the first stage of its change from a charitable to a public health hospital institution were presented. This study revealed the aspiration of the authorities in the first half of the 19th century to improve the health system of the city of Split.  相似文献   
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