We have previously reported that phosphorylation of human urokinase on Ser138/303 abolishes its catalytic-independent motogen and proadhesive abilities, whereas receptor binding is not affected. Here we show that substitution of the two relevant serines with glutamic acid residues impairs the ability of urokinase to mobilize a variety of human and mouse cell lines as well as human primary T lymphocytes. Accordingly, urokinase receptor-dependent signaling, leading to cytoskeletal rearrangements and paxillin re-distribution, does not occur in MCF-7 breast carcinoma cells exposed to 'phosphorylation-like' urokinase.
View Article and Find Full Text PDFJ Oral Maxillofac Surg
March 2002
Purpose: The aim of the present study was to present a conservative condylectomy technique (condylectomy performed below the condylar head but high in the condylar neck) and articular disc repositioning as the surgical treatment approach for management of osteochondroma of the head of the mandibular condyle.
Patients And Methods: Six patients (4 females and 2 males) with an average age of 22.3 years (range, 13 to 32 years) and with an osteochondroma of the mandibular condyle were treated with conservative condylectomy.
A chemically bonded beta-cyclodextrin chiral stationary phase for HPLC was prepared in a "one pot" process by the reaction of a phenylated beta-cyclodextrin with silica gel. Various racemic analytes such as drugs (aminoalcohol adrenergic beta-blockers, benzodiazepine anxiolytics, arylpropionic acid antiinflammatory agents) and herbicides (aryloxypropionic acids and esters) were separated on the prepared material. The column showed good chiral recognition ability for most of the solutes tested when using heptane and either 2-propanol or chloroform as organic mobile phase modifiers.
View Article and Find Full Text PDFAm J Respir Crit Care Med
October 2001
We compared the breathing characteristics of 40 infants who subsequently died of sudden infant death syndrome (SIDS) with those of 607 healthy infants matched for sex and age. The infants were between 2 and 19 wk old at the time of recording. Compared with the control group, the infants who died of SIDS experienced significantly more frequent episodes of obstructive and mixed sleep apnea.
View Article and Find Full Text PDFA stereoselective ion-pair nonaqueous capillary electrophoresis (NACE) method employing the partial filling technique with N-derivatized amino acids, e.g., (R)- and (S)-3,5-dinitrobenzoyl-leucine (DNB-Leu), as chiral selector for the separation of "pseudoenantiomeric" cinchona alkaloid derivatives and other structurally related basic compounds like the enantiomers of mefloquine is presented.
View Article and Find Full Text PDFWe analyzed the influence of presenilins on the genetic cascades that control neuronal differentiation in Xenopus embryos. Resembling sonic hedgehog (shh) overexpression, presenilin mRNA injection reduced the number of N-tubulin+ primary neurons and modulated Gli3 and Zic2 according to their roles in activating and repressing primary neurogenesis, respectively. Presenilin increased shh expression within its normal domain, mainly in the floor plate, whereas an antisense X-presenilin-alpha morpholino oligonucleotide reduced shh expression.
View Article and Find Full Text PDFA new device for the assessment of instantaneous angular and linear accelerations of the head is presented, which is based on four linear tri-axial accelerometers suitably attached to the head by an helmet. A procedure for reproducible helmet placement and calibration is given. A method is also illustrated to work out the different linear accelerations sensed by the vestibular organs in the left and right labyrinths and the components of the angular acceleration sensed by their semicircular canals.
View Article and Find Full Text PDFA combination of in vivo and in vitro assays was employed to describe the ligand-independent interaction of the orphan nuclear receptor TR2 and histone deacetylase proteins. The repressive effect of TR2 on transcription of a luciferase reporter driven by a promoter containing a direct repeat-5 (DR5) derived from the human RARbeta gene was suppressed by the addition of the histone deacetylase inhibitor trichostatin A. Immunoprecipitation with FLAG-epitope (MDYKDDDDK)-tagged histone deacetylase proteins was used to demonstrate that TR2 and histone deacetylases 3 or 4 are present in the same immunoprecipitated complex.
View Article and Find Full Text PDFIn this study we show that SV-IV, a major immunomodulatory, anti-inflammatory, and sperm immunoprotective protein secreted from the rat seminal vesicle epithelium, acts in vitro as a substrate of protein kinase C (PKC) competing efficiently with H1 histone, a very well known PKC substrate. Electrospray mass spectrometry (ES-MS) analysis demonstrated that approximately 10% of the native SV-IV molecules were phosphorylated by PKC and that such a modification involved only a single serine residue (Ser58) out of the 22 occurring in the protein. Interestingly, this modification produced a substantial enhancement (approximately 50%) of the native SV-IV's ability to stimulate the activity of both horseradish peroxidase (POD) and selenium-dependent glutathione peroxidase (GPX), an enzyme that is known to protect the mammalian spermatozoa from oxidative stress and loss of motility in the female genital tract following ejaculation.
View Article and Find Full Text PDFBiochim Biophys Acta
February 2001
The melibiose carrier from Escherichia coli is a cation-substrate cotransporter that catalyzes the accumulation of galactosides at the expense of H(+), Na(+), or Li(+) electrochemical gradients. Charged residues on transmembrane domains in the amino-terminal portion of this carrier play an important role in the recognition of cations, while the carboxyl portion of the protein seems to be important for sugar recognition. In the present study, we substituted Lys-377 on helix XI with Val.
View Article and Find Full Text PDFStudy Objective: To evaluate the influence of ambient temperature on infants' arousability from sleep.
Design: Two groups of healthy infants with a median age of 11 weeks were recorded polygraphically during one night: 31 infants were studied at 24 degreesC and 31 infants at 28 degreesC. To determine their arousal thresholds, the infants were exposed to white noises of increasing intensities during REM and NREM sleep.
Ophthalmic Surg Lasers
August 2001
Background And Objective: GGRGDSPCA synthetic peptide competes for integrin receptor in scar formation after glaucoma filtering surgery in a rabbit model. The purpose of this study was to evaluate the use of this peptide and compare it with mitomycin on glaucoma filtering surgery.
Materials And Methods: Posterior sclerectomy was performed in both eyes of 17 rabbits.
Three "dimeric" C(9)-carbamates of quinine (QN) and quinidine (QD), that is, QN-QN, QD-QD, and QN-QD (chemically prepared mixture of the two cinchona-derived subunits), separated by an ethylene spacer were synthesized and used as chiral selectors for HPLC and capillary electrophoresis (CE) for the resolution of chiral acids. The chiral recognition abilities of these dimers and of several physically prepared mixtures thereof were compared in order to estimate the contribution of every cinchona scaffold to the overall enantioselectivity. The diverse phenomena observed in nonaqueous capillary electrophoresis (NACE), either using the selector added to the background electrolyte (BGE) in the total filling or partial filling mode, led us to rationalize, taking into account the relative mobilities of the chiral selectors in the capillary.
View Article and Find Full Text PDFA decreased arousability and an increased risk for sudden infant death syndrome (SIDS) have been shown in infants sleeping prone. Obstructive apnea, a known risk factor for SIDS, is less often terminated by an arousal reaction in infants than in adults. The effect of body position on the arousal reaction to spontaneous respiratory events had not been previously studied in infants.
View Article and Find Full Text PDFChiral drugs, agrochemicals, food additives and fragrances represent classes of compounds with high economic and scientific potential. First the present implications of their chiral nature and necessity of separating enantiomers are summarised in this article. In the following a brief overview of the actual approaches to perform enantioseparations at analytical and preparative scale is given.
View Article and Find Full Text PDFPolysaccharide derivatives have been extensively used as chromatographic chiral selectors in chiral stationary phases (CSPs) for the separation of enantiomers by HPLC. When coated onto a silica matrix, they represent nowadays one of the most popular type of CSPs. However, they are only compatible with a limited choice of solvents.
View Article and Find Full Text PDFDerivatives of cellulose, amylose and chitosan, bearing simultaneously 10-undecenoyl and arylaminocarbonyl or benzoyl groups were characterized by the combined use of 1H NMR and elemental analysis. The mathematical manipulation of elemental analysis data permits the calculation of the degree of substitution for each kind of substituent. The method was validated and is applicable to other derivatives.
View Article and Find Full Text PDFObjective: To review the major confounding factors that influence the determination of arousal thresholds in infants.Review of confounding factors: The determination of arousal thresholds in infants measures their arousability from sleep. The evaluation is influenced by various conditions.
View Article and Find Full Text PDFStudy Objectives: To collect normative data on the frequency of obstructive and mixed sleep apneas in healthy infants.
Study Design: 1100 infants were recorded during one night in a sleep laboratory.
Setting: the recordings were performed in an infant sleep laboratory.
Objective: The risk of sudden infant death during sleep was postulated to decrease with the use of a pacifier and by conditions facilitating arousals from sleep. We evaluated the influence of a pacifier on arousal from sleep in healthy infants.
Study Design: Fifty-six healthy infants were studied with polygraphy during 1 night; 36 infants used a pacifier regularly during sleep, and 20 never used a pacifier.
Objective: To evaluate the influence of ambient temperature on infant's sleep and cardiorespiratory parameters during sleep.
Patients And Method: 20 healthy infants with a median age of 11.5 weeks (range 7 to 18 weeks) were recorded polygraphically for one night.
Background: Primary hyperaldosteronism is an uncommon cause of hypertension in the general population. Given the mechanism of action of aldosterone clinical manifestations may not occur in the setting of end stage renal disease. However, if a successful renal transplant is performed clinical manifestations may occur.
View Article and Find Full Text PDF