30 research outputs found
Autisme et stress familial : le burn-out parental DĂ©fier les barriĂšres sociales pour des perspectives dâĂ©panouissement personnel - regard de psychologie positive
Le mot « autiste » prend son origine de la langue grecque, (autos) signifie soi-mĂȘme. Il a Ă©tĂ© employĂ© en 1911 par le psychiatre suisse Eugen Bleuler pour qualifier les patients schizophrĂšnes repliĂ©s sur eux-mĂȘmes. L'autisme est un trouble neuro-dĂ©veloppemental, caractĂ©risĂ© par des altĂ©rations de la communication verbale et non verbale, pendant les relations sociales et lors des comportements et des activitĂ©s Ă caractĂšre restreint et rĂ©pĂ©titif [1]. Ces symptĂŽmes apparaissent avant lâĂąge de 3 ans et sont regroupĂ©s sous lâappellation      « triade autistique » et plus prĂ©cisĂ©ment des anomalies de comportement.       L'autisme est considĂ©rĂ© comme un problĂšme de santĂ© publique. Plusieurs facteurs sont Ă l'origine de trouble, y compris ceux qui sont de nature gĂ©nĂ©tique.     Les Ă©tudes gĂ©nĂ©tiques des formes mono gĂ©niques du trouble du spectre autistique (TSA) ont identifiĂ© la fonction synaptique comme l'une des voies molĂ©culaires des troubles neuro-dĂ©veloppementaux sous-jacents [2]. Plusieurs gĂšnes sont mis en cause, notamment les gĂšnes des neuroligines, des protĂ©ines d'adhĂ©sion post-synaptiques des cellules impliquĂ©es dans la maturation du systĂšme nerveux et la plasticitĂ© des rĂ©seaux neuronaux [3]
Caractérisation antibiotypique et biochimique des souches marocaines de Salmonella enteritidis d'origine humaine et alimentaire
Lâantibiotypie et la biotypie des souches marocaines de Salmonella enteritidis dâorigine humaine et alimentaire ont Ă©tĂ© investiguĂ©es. Cinquante et une souches ont Ă©tĂ© isolĂ©es entre janvier 96 et dĂ©cembre 97. Parmi les 31 souches humaines, dix souches se sont rĂ©vĂ©lĂ©es rĂ©sistantes aux antibiotiques dont quatre Ă©taient rĂ©sistantes Ă plus dâun antibiotique. Parmi les 20 souches alimentaires, onze Ă©taient rĂ©sistantes dont 6 rĂ©sistantes Ă plus dâun antibiotique. Les rĂ©sultats obtenus montrent une similitude avec les souches mĂ©diterranĂ©ennes. Les profils biochimiques atypiques Ă©taient rencontrĂ©s aussi bien pour les souches alimentaires que pour les souches humaines. Lâatypie affecte aussi bien les souches sensibles que les souches rĂ©sistantes aux antibiotiques. Les caractĂšres atypiques concernent le mĂ©tabolisme de certains sucres et acides aminĂ©s
Silicon-hydroxyapatite bioactive coatings (Si-HA) from diatomaceous earth and silica. Study of adhesion and proliferation of osteoblast-like cells
The aim of this study consisted on investigating
the influence of silicon substituted hydroxyapatite (SiâHA)
coatings over the human osteoblast-like cell line (SaOS-2)
behaviour. Diatomaceous earth and silica, together with
commercial hydroxyapatite were respectively the silicon
and HA sources used to produce the SiâHA coatings. HA
coatings with 0 wt% of silicon were used as control of the
experiment. Pulsed laser deposition (PLD) was the selected
technique to deposit the coatings. The SiâHA thin films
were characterized by Fourier Transformed Infrared
Spectroscopy (FTIR) demonstrating the efficient transfer of
Si to the HA structure. The in vitro cell culture was
established to assess the cell attachment, proliferation and
osteoblastic activity respectively by, Scanning Electron
Microscopy (SEM), DNA and alkaline phosphatase (ALP)
quantification. The SEM analysis demonstrated a similar
adhesion behaviour of the cells on the tested materials and
the maintenance of the typical osteoblastic morphology
along the time of culture. The SiâHA coatings did not
evidence any type of cytotoxic behaviour when compared
with HA coatings. Moreover, both the proliferation rate
and osteoblastic activity results showed a slightly better
performance on the SiâHA coatings from diatoms than on
the SiâHA from silica.This work was supported by the UE-Interreg IIIA (SP1.P151/03) Proteus project and Xunta de Galicia ( Projects: 2006/12 and PGIDITO5PXIC30301PN)
Impedance and electric modulus study of amorphous TiTaO thin films: highlight of the interphase effect
International audienc
Structural and dielectric characterization of sputtered Tantalum Titanium Oxide thin films for high temperature capacitor applications
International audienc
Silicon Nitride: A Synthetic Mineral for Vertebrate Biology
The remarkable stoichiometric flexibility of hydroxyapatite (HAp) enables the formation of a variety of charged structural sites at the materialâs surface which facilitates bone remodeling due to binding of biomolecule moieties in zwitterionic fashion. In this paper, we report for the first time that an optimized biomedical grade silicon nitride (Si(3)N(4)) demonstrated cell adhesion and improved osteoconductivity comparable to highly defective, non-stoichiometric natural hydroxyapatite. Si(3)N(4)âs zwitterionic-like behavior is a function of the dualism between positive and negative charged off-stoichiometric sites (i.e., N-vacancies versus silanols groups, respectively). Lattice defects at the biomaterialâs surface greatly promote interaction with positively- and negatively-charged functional groups in biomolecules, and result in the biologically effective characteristics of silicon nitride. These findings are anticipated to be a starting point for further discoveries of therapeutic bone-graft substitute materials