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The preparation of sol-gel glasses is described wherein highly stable Eu(III) centres are anchored to the silica glass upon acidic hydrolysis and by using tetraethylorthosilicate (TEOS) as a silica source. The complex employed is Eu?1 and is obtained from bipartite ligand 1, which features a DO3A macrocycle as a hosting unit for the Eu(III) centre, a methoxy-acetophenone unit as an antenna chromophore, and an alkyl chain bearing one primary hydroxy group (DO3A is 1,4,7,10- tetraazacyclododecane-1,4,7-triacetic acid). Eu?1 is linked to the forming silica glass through the -OH groups and a uniform distribution of the luminescent centres is obtained, as indicated by results from secondary ion mass spectrometry in-depth profiling. The luminescent efficiency of the Eu(III) centres in the solid matrix is evaluated to be 10%, which is comparable to that of Eu?1 in water solution and of a convenient reference complex, Eu?2 (2 is a ligand featuring the same hosting and antenna functionalities of 1, wherein the -OH residue is replaced by an unreactive group, a benzoylmethyl residue). A discussion is given of the photophysical properties exhibited by the complexes in the film and in solution.

Two new compounds with four tertiary arylamine moieties connected in a fully para-conjugated system have been synthesised in order to obtain new molecules having low ionisation potentials, as required for hole transporting materials in organic light emitting diodes (OLEDs). Their electrochemical properties have been measured and compared to seven different commercial triarylamines tested in the same experimental conditions. Using the AM I geometries and the statistical average of orbital potential method (SAOP), the redox potentials of the molecules have been estimated and found to be in good agreement with the experimental data. An evident correlation between the molecular geometry and the electrochemical potential of the first oxidation exists and shows that, for equal number of para-conjugated triarylamine moieties, the starburst configuration is more efficient than the linear one in lowering the oxidation potential and that the amine moieties of the inner sphere play a more important role than those of the outer sphere. Besides, amine moieties connected by a biphenyl bridge show generally higher ionisation potentials than those connected via one phenylene.

Polyconjugated regular bithiophene-alt-thiophene-S,S-dioxide copolymers were produced by anodic coupling of variously 3,4-ethylenedioxy-substituted 2,5-bis(2-thienyl)thiophene-S,S-dioxide. The polymers were characterized by cyclic voltammetry, FTIR reflection-absorption and UV-vis spectroscopy, MALDI-TOF mass spectroscopy,electrochemical quartz crystal microbalance, in situ ESR and in situ conductivity techniques, photo- and electroluminescence measurements. The regular alternation of electron-rich and -poor thiophene rings in the polymer chain operated by the ethylenedioxy and S,S-dioxide moieties produces a finite window of conductivity. Alkylprotection of the b-positions of the thiophene-S,S-dioxide ring gave low-defect and soluble oligomers which were investigated in single-layer organic light-emitting devices (OLEDs). Photoluminescence quantum efficiency of ca. 1% and external electroluminescence quantum efficiencies of 0.01% photon/electron at a luminance of 100 cd m22 were obtained.

Polyconjugated regular bithiophene-alt-thiophene-S,S-dioxide copolymers were produced by anodic coupling of variously 3,4-ethylenedioxy-substituted 2,5-bis(2-thienyl)thiophene-S,S-dioxide. The polymers were characterized by cyclic voltammetry, FTIR reflection-absorption and UV-vis spectroscopy, MALDI-TOF mass spectroscopy, electrochemical quartz crystal microbalance, in situ ESR and in situ conductivity techniques, photo- and electroluminescence measurements. The regular alternation of electron-rich and -poor thiophene rings in the polymer chain operated by the ethylenedioxy and S,S-dioxide moieties produces a finite window of conductivity. Alkylprotection of the b-positions of the thiophene-S,S-dioxide ring gave low-defect and soluble oligomers which were investigated in single-layer organic light-emitting devices (OLEDs). Photoluminescence quantum efficiency of ca. 1% and external electroluminescence quantum efficiencies of 0.01% photon/electron at a luminance of 100 cd m2 were obtained.

L'utilisation de matériel micropropagé par technique in vitro permet une réduction du temps des essais, et une augmentation du nombre des variétés à tester, ainsi que du nombre de répétitions. Après 3 à 4 semaines d'endurcissement, les jeunes plants sont prêts à être plantés en pot de 800 cm@3 de terreau stérilisé. A 27-28 ¼C, une inoculation de 100 Radopholus similis/plant suffit pour observer des différences dans le développement des populations 8 semaines plus tard (résistance). Avec un inoculum plus important (200-400 R. similis) et une plus longue période, on observe des différences dans le développement des racines et des plants (tolérance). Les résultats obtenus sont reproductibles et sont conformes aux observations préliminaires faites en collection au champ. Cette technique est d'une manipulation facile et permet de vérifier la résistance à d'autres espèces de migrateurs. Elle peut être adaptée aux espèces sédentaires

Le pouvoir pathogène de 6 isolats de Radopholus similis, récoltés dans différentes zones de production bananière, a été étudié en pots en conditions contrôlées dans une chambre climatique. Les nématodes, élevés en conditions monoxéniques sur rondelles de carottes, ont été inoculés sur de jeunes plants de bananiers (AAA, cv. Poyo) issus de micropropagation in vitro. Les isolats du Sri lanka et de Martinique n'ont eu aucun effet significatif sur la croissance des plants alors que ceux de Guadeloupe, du Costa Rica, du Kenya et de Côte d'Ivoire ont eu un effet dépressif important. L'isolat de Côte d'Ivoire s'est révélé être le plus pathogène. Ces résultats confirme l'existence d'une grande variabilité biologique entre populations de R. similis séparées géographiquement.

L'utilisation de jeunes plants issus de micropropagation in vitro permet une détection rapide et précoce de variétés résistantes ou tolérantes aux nématodes. Les jeunes bananiers sont progressivement acclimatés aux conditions aériennes pendant 3 à 4 semaines avant d'être transplantés dans des pots contenant du sol stérilisé. Les nématodes (Radopholus similis) proviennent d'élevages in vitro sur rondelles de carottes et sont inoculés 2 à 3 semaines après la mise en pots des bananiers. Un inoculum de 100 R. similis par plant est suffisant pour observer des différences significatives de multiplication des nématodes dans les racines, 8 semaines après l'inoculation (évaluation de la résistance). Pour observer des différences au niveau de la croissance végétative (évaluation de la tolérance), une augmentation de l'inoculum et/ou de l'intervalle de temps entre inoculation et observations est nécessaire. Les 5 variétés testées dans le cadre de cette mise au point se sont échelonnées entre une résistance partielle importante (Yangambi km 5) et une forte sensibilité (Poyo). Ces résultats sont conformes aux observations qui avaient été faites au champ. Le test mis au point est donc fiable. Cette méthode peut être facilement aménagée pour le criblage d'autres genres de nématodes (Pratylenchus, Meloidogyne, etc.)

Le test précoce de criblage variétal pour la détection de bananiers résistants à Radopholus similis, mis au point par Blavignac en 1989, a été renouvelé sur les variétés 'Yangambi Km5' (AAA) et Cavendish 'Poyo' (AAA). Les résultats de 1989 ont été confirmés et la fiabiité du test mise en évidence. Les bananiers ont été inoculés avec des doses de 100, 300 ou 800 nématodes par plant. Les populations de nématodes étaient originaires de Côte d'Ivoire, de Guadeloupe, de Martinique et du Costa-Rica. Les doses élevées d'inoculum se sont révélées les meilleures pour souligner, chez la 'Poyo', les densités racinaires de population les plus élevées et les masses foliaires et racinaires les plus faibles. La variété 'Yangambi' s'est montrée la moins sensible. Les nématodes de Cote d'Ivoire se sont révélés les plus pathogènes, ceux de la Martinique l'étant le moins. Des analyses biochimiques ont permis de constater des modifications des teneurs en minéraux, sucres et acides organiques dans les plants inoculés. (d'après résumé d'auteur)

Although relatively rare, meningococcal disease represents a global health problem being still the leading infectious cause of death in childhood with an overall mortality around 8%. Menin- gococcal meningitis is the most commonly recognized presenta- tion, accounting for 80% to 85% of all reported cases of menin- gococcal disease (in half of these cases sepsis is also present con- comitantly). The remaining 15-20% of cases are most commonly bloodstream infections only. Meningococcal serogroups A, B, and C account for most cases of meningococcal disease throughout the world. Recently, serogroups W-135 and X (predominantly in Africa) and group Y (in the United States and European countries) have emerged as important disease-causing isolates. Despite recent advances in medical management, the mortality rate of fulminant meningococcemia ranges from 15% to 30%. However, among survivors, 10-30% could have long term sequelae (i.e. sensoneural hearing loss, seizure, motor problems, hydrocepha- lus, mental retardation, and cognitive and behavioral problems). Considering the clinical severity of meningococcal disease, pre- vention represents the first approach for avoiding serious com- plications and possible deaths. The availability of new vaccines able to cover the emerging serotypes including A and Y as well as the availability on the market of new products that could prevent meningococcal B infection represent a great opportunity for the decrease of the burden of this complicated disease. The full article is free available on www.jpmh.org, Journal of Preventive Medicine and Hygiene, Vol 53, No 2 (2012)

Various studies have confirmed the high incidence of skeletal homeostasis modifications in subjects who are carriers of chronic HIV infections, and specific pharmacological treatments, which modify the metabolism and condition both the weight loss and the reshaping of the bones. The presence of a reduction in body mass index seems to contribute to the progressive deterioration of the skeletal framework. The aim of this study was to see whether the presence of HIV-seropositivity could constitute a risk factor for the development of osteoporosis/osteopenia, even in the light of the fact that our group was composed of patients with a concentrated age span well under the limit for both post-menopausal and senile osteoporosis, and with a median age superimposable for both sexes.Our study involved 26 HIV+ patients with an average duration of infection equal to 6.7 +/- 4.8 years, and a range of seropositive duration between 6 months to 16 years. The prominent ultrasonometrical parameters are as follows: Broadband Ultrasound Attenuation, Speed of Sound, Stiffness Index or Quantitative Ultra-sound Index, Bone Mineral Density, and T-score. The biochemical study was carried out by assessing a marker of neoformation such as seric osteocalcine, and uninary pyridinoline and deoxipyridonoline as resorption markers.The results confirmed the presence of osteoporosis/osteopenia in 46% of the samples (11%, and 35%, respectively), with a progressive reduction in bone mineral density in relation to the duration of HIV infection. Assessment of the marker for bone metabolism showed a significant increase in osteocalcine in the female population compared to the males, without any significant variations in the normal values.Extreme variability in the morphological appearance at bone level during the course of HIV infection would lead us to believe that in the genesis of various forms, depending on the mechanisms and the time involved only in the parts defined, other attributable factors are responsible, not only for the progression of the core pathology and the possible interference of hormonal factors (behavioural and/or nutritional) directly correlated with the state of infection, but also for the dismetabolic effects of the antiretroviral drugs.