34 research outputs found

    Creatine Transporter Defect Diagnosed by Proton NMR Spectroscopy in Males With Intellectual Disability

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    Creatine deficiency syndrome due to mutations in X-linked SLC6A8 gene results in nonspecific intellectual disability (ID). Diagnosis cannot be established on clinical grounds and is often based on the assessment of brain creatine levels by magnetic resonance spectroscopy (MRS). Considering high costs of MRS and necessity of sedation, this technique cannot be used as a first level-screening test. Likewise, gene test analysis is time consuming and not easily accessible to all laboratories. In this article feasibility of urine analysis (creatine/creatinine (Cr/Crn) ratio) performed by nuclear magnetic resonance (NMR) as a first level-screening test is explored. Before running a systematic selection of cases a preliminary study for further molecular analysis is shown. NMR urine spectra (n = 1,347) of male patients with an ID without a clinically recognizable syndrome were measured. On the basis of abnormal Cr/Crn ratio, three patients with the highest values were selected for molecular analysis. A confirmatory second urine test was positive in two patients and diagnosis was further confirmed by a decreased brain creatine level and by SLC6A8 gene analysis. A de novo mutation was identified in one. Another patient inherited a novel mutation from the mother who also has a mild ID. A repeat urine test was negative in the third patient and accordingly creatine level in the brain and SLC6A8 gene analysis both gave a normal result. We conclude that Cr/Crn ratio measured by NMR for male patients represents a rapid and useful first level screening test preceding molecular analysis. © 2011 Wiley-Liss, Inc

    Evidence of Unprecedented High Electronic Conductivity in Mammalian Pigment Based Eumelanin Thin Films After Thermal Annealing in Vacuum

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    Melanin denotes a variety of mammalian pigments, including the dark electrically conductive eumelanin and the reddish, sulfur-containing, pheomelanin. Organic (bio)electronics is showing increasing interests in eumelanin exploitation, e.g., for bio-interfaces, but the low conductivity of the material is limiting the development of eumelanin-based devices. Here, for the first time, we report an abrupt increase of the eumelanin electrical conductivity, revealing the highest value presented to date of 318 S/cm. This result, obtained via simple thermal annealing in vacuum of the material, designed on the base of the knowledge of the eumelanin chemical properties, also discloses the actual electronic nature of this material's conduction

    Hydrodechlorination of Aroclor 1260 in aqueous two-phase mixture catalyzed by biogenerated bimetallic catalysts

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    The PCBs are known recalcitrant and toxic pollutants and significant values of contamination could be found in water. PCBs can be hydrodechlorinated using Pd-based catalysts and hydrogen, but the research to identify more efficient heterogeneous catalysts, able to work in an aqueous phase, less sensible to deactivation and easily removable at the end of the treatment, remains a considerable interesting goal. A strain of Klebsiella oxytoca, DSM 29614, known to produce a specific exopolysaccaride (EPS), was grown in different media with sodium citrate or with sodium citrate plus ferric citrate, as sole energy and carbon sources under anaerobic conditions. The cultures were amended with 50 mg of palladium as Pd(NO3)2 to generate Pd-EPS (Pd content 13%) or FePd-EPS (Pd content 8.4%; Fe 7.4%) species which were secreted from the cells, isolated by treatment with a cold ethanol solution (70%) and dried under vacuum as powders. The catalytic ability of these mono- and bi-metallic species was tested in the hydrodechlorination reaction of the Aroclor 1260 PCBs mixture under aqueous biphasic conditions. Here we demonstrate that the degree of PCBs hydrodechlorination is dependent by the nature of catalyst and of base used to neutralize HCl produced, the bimetallic species being more active and an organic base resulting more effective. Working with a substrate/catalyst 8/1 molar ratio, at 3 MPa H2 and 60°C in 20 h a significant removal of highly chl orinated PCBs was obtained under the best conditions. The result seems promising for remediation of groundwater contaminated with PCBs

    Creatine transporter defect diagnosed by proton NMR spectroscopy in males with intellectual disability.

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    Creatine deficiency syndrome due to mutations in X-linked SLC6A8 gene results in nonspecific intellectual disability (ID). Diagnosis cannot be established on clinical grounds and is often based on the assessment of brain creatine levels by magnetic resonance spectroscopy (MRS). Considering high costs of MRS and necessity of sedation, this technique cannot be used as a first level-screening test. Likewise, gene test analysis is time consuming and not easily accessible to all laboratories. In this article feasibility of urine analysis (creatine/creatinine (Cr/Crn) ratio) performed by nuclear magnetic resonance (NMR) as a first level-screening test is explored. Before running a systematic selection of cases a preliminary study for further molecular analysis is shown. NMR urine spectra (n = 1,347) of male patients with an ID without a clinically recognizable syndrome were measured. On the basis of abnormal Cr/Crn ratio, three patients with the highest values were selected for molecular analysis. A confirmatory second urine test was positive in two patients and diagnosis was further confirmed by a decreased brain creatine level and by SLC6A8 gene analysis. A de novo mutation was identified in one. Another patient inherited a novel mutation from the mother who also has a mild ID. A repeat urine test was negative in the third patient and accordingly creatine level in the brain and SLC6A8 gene analysis both gave a normal result. We conclude that Cr/Crn ratio measured by NMR for male patients represents a rapid and useful first level screening test preceding molecular analysis

    Eumelanin Precursor 2-Carboxy-5,6-Dihydroxyindole (DHICA) as Doping Factor in Ternary (PEDOT:PSS/Eumelanin) Thin Films for Conductivity Enhancement

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    The integration of the pristine not-doped commercial poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) PH1000 with eumelanin, the brown to black kind of melanin pigment, was achieved by dissolving the melanogenic precursors 2-carboxy-5,6-dihydroxyindole (DHICA) in the PH1000 suspension. Solid state oxidative polymerization of the catecholic indole allowed obtaining the ternary blend PEDOT:PSS/eumelanin. The introduction of DHICA into PH1000 produced a noticeable increase in the conductivity of PEDOT thin films akin to that produced by dimethyl sulfoxide (DMSO) treatment, opening up novel strategies for the simultaneous integration of eumelanin polymer and conductivity enhancement of PEDOT containing coatings, as well as the long term goal of replacing PSS by DHICA eumelanin for PEDOT pairing

    Electron beam curing technology for very high-throughput manufacturing of flexible alternating current powder electroluminescent devices

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    Thick-film alternating current powder-based electroluminescent (ACPEL) succeeds on the market as mature technology for large-area light sources. An additional boost for its development may come from the radiation curing technology. Since it is totally compatible with high-speed roll-to-roll processing, radiation curing can offer multiple advantages to further lower costs and make easier the fabrication process of ACPEL devices. In this paper, the application of the electron beam (EB) curing technology to produce flexible ACPEL devices was explored for the first time. In particular, devices with emitting layer made by EB irradiation were successfully fabricated on poly(ethylene terephthalate) (PET) substrate. Device properties were evaluated and compared with those obtained using the conventional ultraviolet curing process. Smaller driving voltages and higher luminous output were observed for the EB treated samples as a consequence of a more cross-linked polymeric binder of the emitting layer generated. In addition, possible effects of EB overdose were also investigated; experiments revealed that excessively high doses can induce the degradation of both polymeric binder and emitting particles. Therefore, the feasibility of using the EB curing was proven to fabricate ACPEL devices, launching it as the next future technology for more sustainable, very fast, and one-step manufacturing of powder-based alternating current EL devices

    A metabolomic study of preterm and term human and formula milk by proton MRS analysis: Preliminary results

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    Objective: To investigate changes in global metabolic profile between: 1-breast milk and formula milk, 2-breast milk from mothers delivering at different gestational age (GA) collected within one week from delivery, and then week by week until term equivalent age. Methods: Proton magnetic resonance spectroscopy (MRS) was used to analyze the water-soluble and lipid fractions extracted from 50 milk samples, 46 human milk at different GA, from 23 weeks of gestation until term equivalent age and four different formula milks. Results: The formula milk for premature infants was the most similar to breast milk of preterm babies. Breast milk showed higher lactose concentrations than formula milk, that conversely presented higher galactose 1-phosphate and maltose concentrations. Mother's milk of very preterm babies (23-25 wks of GA) showed a different metabolic profile from preterm infants 29 wks of GA with a subsequent trend to similarity around the 30th week of post-natal age. Breast milk from preterm infants of 29-34 wks, collected up to 40 wks of post-natal age showed a temporal change over the first three weeks of lactation, approaching to zero with the achievement of term age. Conclusions: Metabolome is a promising tool to study human and artificial milk global metabolic profile
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