Improved photocatalytic performance of TiO2/carbon photocatalysts: Role of carbon additive.

A series of TiO2 - based photocatalysts have been prepared by the incorporation of 10 wt% of various carbon-based nanomaterials as modifying agents to titania. More specifically, commercial TiO2 P25 was modified through a wet impregnation approach with methanol with four different carbon nanostructures: single-walled carbon nanotubes (SWCNTs), partially reduced graphene oxide (prGO), graphite (GI), and graphitic carbon nitride (gCN). Characterization results (XPS and Raman) anticipate the occurrence of important interfacial phenomena, preferentially for samples TiO2/SWCNT and TiO2/prGO, with a binding energy displacement in the Ti 2p contribution of 1.35 eV and 1.54 eV, respectively. These findings could be associated with an improved electron-hole mobility at the carbon/oxide interface. Importantly, these two samples constitute the most promising photocatalysts for Rhodamine B (RhB) photodegradation, with nearly 100% conversion in less than 2 h. These promising results must be associated with intrinsic physicochemical changes at the formed heterojunction structure and the potential dual-role of the composites able to adsorb and degrade RhB simultaneously. Cyclability tests confirm the improved performance of the composites (e.g., TiO2/SWCNT, 100% degradation in 1 h) due to the combined adsorption/degradation ability, although the regeneration after several cycles is not complete due to partial blocking of the inner cavities in the carbon nanotubes by non-reacted RhB. Under these reaction conditions, Rhodamine-B xanthene dye degrades via the de-ethylation route.

Vaginal neutrophil infiltration is contingent on ovarian cycle phase and independent of pathogen infection.

The mucosa of the female reproductive tract must reconcile the presence of commensal microbiota and the transit of exogenous spermatozoa with the elimination of sexually transmitted pathogens. In the vagina, neutrophils are the principal cellular arm of innate immunity and constitute the first line of protection in response to infections or injury. Neutrophils are absent from the vaginal lumen during the ovulatory phase, probably to allow sperm to fertilize; however, the mechanisms that regulate neutrophil influx to the vagina in response to aggressions remain controversial. We have used mouse inseminations and infections of Neisseria gonorrhoeae, Candida albicans, Trichomonas vaginalis, and HSV-2 models. We demonstrate that neutrophil infiltration of the vaginal mucosa is distinctively contingent on the ovarian cycle phase and independent of the sperm and pathogen challenge, probably to prevent sperm from being attacked by neutrophils. Neutrophils extravasation is a multi-step cascade of events, which includes their adhesion through selectins (E, P and L) and integrins of the endothelial cells. We have discovered that cervical endothelial cells expressed selectin-E (SELE, CD62E) to favor neutrophils recruitment and estradiol down-regulated SELE expression during ovulation, which impaired neutrophil transendothelial migration and orchestrated sperm tolerance. Progesterone up-regulated SELE to restore surveillance after ovulation.

Metformin to treat Huntington disease: A pleiotropic drug against a multi-system disorder.

Huntington disease (HD) is a neurodegenerative disorder produced by an expansion of CAG repeats in the HTT gene. Patients of HD show involuntary movements, cognitive decline and psychiatric impairment. People carrying abnormally long expansions of CAGs (more than 35 CAG repeats) produce mutant huntingtin (mHtt), which encodes tracks of polyglutamines (polyQs). These polyQs make the protein prone to aggregate and cause it to acquire a toxic gain of function. Principally affecting the frontal cortex and the striatum, mHtt disrupts many cellular functions. In addition, this protein is expressed ubiquitously, and some reports show that many other cell types are affected by the toxicity of mHtt. Several studies reported that metformin, a widely-used anti-diabetic drug, is neuroprotective in models of HD. Here, we provide a review of the benefits of this substance to treat HD. Metformin is a pleiotropic drug, modulating different targets such as AMPK, insulin signalling and many others. These molecules regulate autophagy, chaperone expression, and more, which in turn reduce mHtt toxicity. Moreover, metformin alters gut microbiome and its metabolic processes. The study of potential targets, interactions between the drug, host and microbiome, or genomic and pharmacogenomic approaches may allow us to design personalised medicine to treat HD.

Delphi consensus on recommendations for the treatment of spinal muscular atrophy in Spain (RET-AME consensus).

INTRODUCTION: Spinal muscular atrophy (SMA) is a neurodegenerative disease caused by a biallelic mutation of the SMN1 gene, located on the long arm of chromosome 5, and predominantly affects the motor neurons of the anterior horn of the spinal cord, causing progressive muscle weakness and atrophy. The development of disease-modifying treatments is significantly changing the natural history of SMA, but uncertainty remains about which patients can benefit from these treatments and how that benefit should be measured. METHODOLOGY: A group of experts specialised in neurology, neuropediatrics, and rehabilitation and representatives of the Spanish association of patients with SMA followed the Delphi method to reach a consensus on 5 issues related to the use of these new treatments: general aspects, treatment objectives, outcome assessment tools, requirements of the treating centres, and regulation of their use. Consensus was considered to be achieved when a response received at least 80% of votes. RESULTS: Treatment protocols are useful for regulating the use of high-impact medications and should guide treatment, but should be updated regularly to take into account the most recent evidence available, and their implementation should be assessed on an individual basis. Age, baseline functional status, and, in the case of children, the type of SMA and the number of copies of SMN2 are characteristics that should be considered when establishing therapeutic objectives, assessment tools, and the use of such treatments. The cost-effectiveness of these treatments in paediatric patients is mainly influenced by early treatment onset; therefore, the implementation of neonatal screening is recommended. CONCLUSIONS: The RET-AME consensus recommendations provide a frame of reference for the appropriate use of disease-modifying treatments in patients with SMA.

Simple template-based optimization for pediatric total lymphoid irradiation (TLI) radiotherapy treatments.

Total lymphoid irradiation (TLI) is used in the management of pediatric allogeneic hematopoietic stem cell transplantation (HSCT. This work aims to simplify the treatment planning process for TLI via a proposed template using the volumetric modulated arc therapy (VMAT) technique. Fifteen pediatric patients were planned, prescribed to 8 Gy in 4 fractions. Cost functions included in the template were the ones for the planning target volume (PTV), and conformality cost function (CCF) for the rest of the patient's volume. Conformity index (CI), homogeneity index (HI), conformation number (CN), gradient index (GI), integral dose, and doses to the organs at risk achieved with the template were reported. Cost function influence over various indexes was studied by Wilcoxon signed ranks test. Same 15 patients were planned with 3-dimensional conventional radiotherapy (3D-CRT) technique for comparison. Mean CI and HI were 1.33 and 0.13, respectively, which indicates good dose conformation and homogeneity. Mean CN and GI values were 0.69 and 4.51, respectively. Mean PTV coverage was reached (V100% > 95%). No correlation between the CCF and indexes values was found (p > 0.05). Doses to organs at risk (OARs) were as low as possible without losing PTV coverage. VMAT plan showed higher levels of conformation and similar homogeneity as 3D-CRT plans. Doses to OARs were inferior with VMAT except for the right kidney. The proposed template simplifies the planning of TLI treatments, and it is able to create acceptable plans with little modification in order to reduce doses to certain organs like the kidneys or the heart. VMAT technique showed higher conformation and lower doses to OAR compared to 3D-CRT.

Synergistic activation of AMPK prevents from polyglutamine-induced toxicity in Caenorhabditis elegans.

Expression of abnormally long polyglutamine (polyQ) tracks is the source of a range of dominant neurodegenerative diseases, such as Huntington disease. Currently, there is no treatment for this devastating disease, although some chemicals, e.g., metformin, have been proposed as therapeutic solutions. In this work, we show that metformin, together with salicylate, can synergistically reduce the number of aggregates produced after polyQ expression in Caenorhabditis elegans. Moreover, we demonstrate that incubation polyQ-stressed worms with low doses of both chemicals restores neuronal functionality. Both substances are pleitotropic and may activate a range of different targets. However, we demonstrate in this report that the beneficial effect induced by the combination of these drugs depends entirely on the catalytic action of AMPK, since loss of function mutants of aak-2/AMPKα2 do not respond to the treatment. To further investigate the mechanism of the synergetic activity of metformin/salicylate, we used CRISPR to generate mutant alleles of the scaffolding subunit of AMPK, aakb-1/AMPKß1. In addition, we used an RNAi strategy to silence the expression of the second AMPKß subunit in worms, namely aakb-2/AMPKß2. In this work, we demonstrated that both regulatory subunits of AMPK are modulators of protein homeostasis. Interestingly, only aakb-2/AMPKß2 is required for the synergistic action of metformin/salicylate to reduce polyQ aggregation. Finally, we showed that autophagy acts downstream of metformin/salicylate-related AMPK activation to promote healthy protein homeostasis in worms.

TLI in pediatric patients.

PURPOSE: Hematopoietic progenitor cell transplantation (HSCT) is a procedure used in different hematological diseases as part of the curative treatment, so the investigators propose a system of conditioning of reduced intensity based on total lymphoid irradiation (TLI) as an alternative to the classic total body irradiation (TBI) followed by haploidentical transplantation in patients compatible with a single HLA haplotype, as an alternative to patients who do not have an HLA compatible donor. MATERIALS AND METHODS: A cohort of 25 patients with hematological disease underwent haploidentical HSCT from February 2015 to May 2018, conditioned with TLI from day - 10 (2-4 days of treatment) followed by thiotepa (5 mg/kg/12 h) and melphalan (70 mg/m2/day) prior to HSCT and prophylaxis with ciclosporin (1.5 mg/kg/12 h). 2 Gy/fraction was administered to complete 8 Gy with IMRT and VMAT technique. RESULTS: 12% rejection of the transplant was obtained with acute GVHD < II (48%) and chronic GVHD 12%. No acute toxicity was recorded in irradiated patients and 56% survival of patients at the end of follow-up. CONCLUSION: Conditioning the haploidentical transplant with TLI, IMRT, and VMAT techniques compared with TBI and RT3D-C techniques is a feasible technique that helps inducing the necessary immunosuppression in patients with a high risk of graft rejection, minimal adverse effects, low incidence of GVHD, and high survival rate.

Conducting Polymer-TiO2 Hybrid Materials: Application in the Removal of Nitrates from Water.

Materials able to produce the reduction of nitrate from water without the need of a metal catalyst and with avoiding the use of gaseous hydrogen have been developed by combining the synergistic properties of titania and two conducting polymers. Polymerization of aniline and pyrrol on titanium dioxide in the presence of two different oxidants/dopants (iron trichloride or potassium persulfate) has been evaluated. The resulting hybrid materials have good thermal stability imparted by the titania counterpart, and a considerable conductivity provided by the conducting polymers. The capability of the hybrid materials of reducing aqueous nitrate has been assessed and compared to the catalytic hydrogenation of nitrate using a platinum catalyst supported on these hybrid synthesized materials. The mechanism of nitrate abatement implies adsorption of nitrate on the polymer by ion exchange with the dopant anion, followed by the reduction of nitrate. The electron transfer from titania to the conducting polymer in the hybrid material favors the reductive ability of the polymer, in such a way that nitrate is selectively reduced with a very low production of undesirable side products. The obtained results show that the activity and selectivity of the catalytic reduction of nitrate with dihydrogen in the presence of a platinum catalyst supported on the hybrid materials are considerably lower than those of the metal-free nanocomposites.

Metal-organic and covalent organic frameworks as single-site catalysts.

Heterogeneous single-site catalysts consist of isolated, well-defined, active sites that are spatially separated in a given solid and, ideally, structurally identical. In this review, the potential of metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) as platforms for the development of heterogeneous single-site catalysts is reviewed thoroughly. In the first part of this article, synthetic strategies and progress in the implementation of such sites in these two classes of materials are discussed. Because these solids are excellent playgrounds to allow a better understanding of catalytic functions, we highlight the most important recent advances in the modelling and spectroscopic characterization of single-site catalysts based on these materials. Finally, we discuss the potential of MOFs as materials in which several single-site catalytic functions can be combined within one framework along with their potential as powerful enzyme-mimicking materials. The review is wrapped up with our personal vision on future research directions.

Ventilación con mascarilla facial en decúbito prono para tratamiento radioterápico en niños / Ventilation with facial mask in the prone position for radiotherapy procedures in children

Objetivos. La ventilación de los pacientes para procedimientos en decúbito prono representa un reto para el anestesiólogo, especialmente cuando se intenta evitar la intubación endotraqueal. Presentamos un estudio concebido para comprobar la efectividad y la seguridad de un prototipo diseñado para ventilación con mascarilla facial en decúbito prono en niños. Material y métodos. Estudio descriptivo prospectivo de 105 sedaciones realizadas en 3 niños programados para tratamiento radioterápico en decúbito prono por meduloblastoma desmoplásico de fosa posterior (2 pacientes de 4 y 6 años de edad) y neuroblastoma en área temporal (un paciente de 4 años). La inducción y el mantenimiento de la sedación se realizaron con sevoflurano en oxígeno, manteniendo ventilación espontánea. Tras la pérdida de consciencia e inmovilidad del paciente se procedía a colocarlo en decúbito prono y a fijar su cabeza con frente y cara apoyadas en un prototipo creado con un molde de poliexpan que contenía la mascarilla facial (conectada a un circuito Mapleson D,) y la parte posterior de la cabeza inmovilizada con una capa de material termoplástico. Se recogieron variables de tiempo y posibles complicaciones. Resultados. Las 105 sedaciones se realizaron según el protocolo previsto. No se produjeron desaturaciones por debajo del 95%, movimientos durante el procedimiento ni otras complicaciones. El tiempo de estancia en el hospital incluyendo procedimiento y recuperación postanestésica fue de 54,4 ± 7,9 min (media ± DE). Conclusiones. El prototipo y técnica de sedación con mascarilla facial en decúbito prono empleados fueron efectivos y seguros permitiendo la realización del tratamiento radioterápico, asegurando la vía aérea de forma mínimamente invasiva, manteniendo la ventilación adecuada, una sedación superficial y posibilitando un alta a domicilio precoz (AU)

Objectives. Ventilation of patients undergoing procedures in the prone position represents a challenge for the anesthesiologist, especially when trying to avoid tracheal intubation. This study aimed to test the effectiveness and safety of a prototype designed for pediatric facial mask ventilation in the prone position. Material and methods. A prospective descriptive study was conducted on 105 sedations performed in 3 children scheduled for radiotherapy treatment of posterior fossa desmoplastic medulloblastoma (6 and 4 y.o. males), and neuroblastoma in temporal area (4 y.o. male). Induction and maintenance of sedation were conducted with sevoflurane in oxygen, maintaining spontaneous ventilation. After achieving loss of consciousness and immobility, the patients were placed in the prone position. Their heads were fixed with the forehead and face supported by a prototype made with a cast of expanded polystyrene (EPS), which held the facial mask (connected to a Mapleson D circuit), and the back of the head immobilized with a layer of thermoplastic material. Time variables and complications were recorded. Results. All sedations were performed according to the planned protocol. All patients maintained oxygen saturation levels above 95%, and no complications were reported. Daily hospital length of stay including the procedure and post anesthetic recovery was 54.4±7.9 min (mean ± SD). Conclusions. The prototype and the sedation technique with face mask in the prone position employed were effective and safe, allowing the completion of the radiotherapy sessions and securing the airway in a minimally invasive way, maintaining adequate ventilation, light sedation and enabling early hospital discharge (AU)

Ventilation with facial mask in the prone position for radiotherapy procedures in children.

OBJECTIVES: Ventilation of patients undergoing procedures in the prone position represents a challenge for the anesthesiologist, especially when trying to avoid tracheal intubation. This study aimed to test the effectiveness and safety of a prototype designed for pediatric facial mask ventilation in the prone position. MATERIAL AND METHODS: A prospective descriptive study was conducted on 105 sedations performed in 3 children scheduled for radiotherapy treatment of posterior fossa desmoplastic medulloblastoma (6 and 4 y.o. males), and neuroblastoma in temporal area (4 y.o. male). Induction and maintenance of sedation were conducted with sevoflurane in oxygen, maintaining spontaneous ventilation. After achieving loss of consciousness and immobility, the patients were placed in the prone position. Their heads were fixed with the forehead and face supported by a prototype made with a cast of expanded polystyrene (EPS), which held the facial mask (connected to a Mapleson D circuit), and the back of the head immobilized with a layer of thermoplastic material. Time variables and complications were recorded. RESULTS: All sedations were performed according to the planned protocol. All patients maintained oxygen saturation levels above 95%, and no complications were reported. Daily hospital length of stay including the procedure and post anesthetic recovery was 54.4±7.9 min (mean±SD). CONCLUSIONS: The prototype and the sedation technique with face mask in the prone position employed were effective and safe, allowing the completion of the radiotherapy sessions and securing the airway in a minimally invasive way, maintaining adequate ventilation, light sedation and enabling early hospital discharge.

IP-10 is an accurate biomarker for the diagnosis of tuberculosis in children.

OBJECTIVE: Performance of IFN-γ assays in children is compromised. Therefore, we investigated the utility of IP-10 for the detection of active tuberculosis (TB) and latent tuberculosis infection (LTBI) diagnosis in children; comparing its positivity with QuantiFERON-TB Gold In-Tube (QFN-G-IT) and T-SPOT.TB. METHODS: We studied 230 children from three groups: active TB, screening (healthy children without known exposure to active TB patient screened at school or by their paediatrician) and contact-tracing studies. IFN-γ release was determined by QFN-G-IT and T-SPOT.TB. IP-10 was detected in QFN-G-IT supernatants by ELISA. RESULTS: When combining QFN-G-IT and IP-10 assays, positive results improved significantly from 38.3% in QFN-G-IT and 33.9% in IP-10 to 41.3%. Age and type of contact were significant risk factors associated with positive QFN-G-IT and IP-10 results. IP-10 levels after antigen-specific stimulation were significantly higher in comparison to IFN-γ levels. Correlation between the three assays was good (κ = 0.717-0.783). CONCLUSIONS: IP-10 cytokine is expressed in response to TB specific-antigens used in QFN-G-IT. In conclusion, the use of IFN-γ T-cell based assays in combination with an additional IP-10 assay detection could be useful for diagnosing active TB and LTBI in children.

Markers of airway inflammation in the exhaled breath condensate of preschool wheezers.

BACKGROUND: Leukotrienes (LT), isoprostanes, and nitrites/nitrates are biomarkers of airway inflammation and oxidative stress that can be detected in exhaled breath condensate (EBC). The aim of this study was to evaluate LTB4, LTE4, 8-isoprostane, and nitrite/nitrate levels in the EBC of healthy and wheezing preschool children. METHODS: We included 21 healthy nonatopic children and 25 patients with recurrent wheezing episodes in a cross-sectional study. LTB4, LTE4, and 8-isoprostane concentrations were measured directly in EBC using a specific enzyme immunoassay; nitrite/nitrate concentrations were measured using a colorimetric assay. RESULTS: LTB4 concentrations were higher in children with wheezing episodes than in healthy controls (76 pg/mL vs 20 pg/mL, P < .001). LTE4 was increased in children with wheezing episodes than in healthy controls (68 pg/mL vs 35 pg/mL, P < .001). Nitrite concentrations were higher in children with wheezing episodes than in healthy controls (14 pg/mL vs 9.7 pg/mL, P < .03). We found no differences in 8-isoprostane and nitrate concentrations between the patients and the healthy controls. CONCLUSIONS: Our findings suggest that EBC is a suitable noninvasive method for the assessment of airway inflammation and oxidative stress in preschool children. Levels of LTB4, LTE4, and nitrites were higher in children with recurrent wheezing episodes than in healthy controls.

Morphological and molecular identification of Tetratrichomonas flagellates from the giant anteater (Myrmecophaga tridactyla).

A tetratrichomonad flagellate found in the diarrhoeic faeces of a 5 years-old male giant anteater (Myrmecophaga tridactyla) was characterised by morphological and genetic analysis. This protozoan presents four anterior flagella of unequal length and a recurrent flagellum attached to the undulating membrane without a free end portion, and a broad axostyle projection. Numerous vacuoles of different sizes containing bacteria and digestion products were found. The complete sequence of the DNA coding for the 16S rRNA-ITS1-5.8S rRNA-ITS2 region was also obtained in order to compare this isolate with other tetratrichomonad species. The sequence obtained was identical to others previously obtained by other researchers from bovines and turtles (Geochelone sp.). It is not easily explainable how the same organism could be found in such different hosts and locations; however these results indicate that some tetratrichomonad species could have a wide host range and could survive in a wide range of environmental conditions.

Markers of Airway Inflammation in the Exhaled Breath Condensate of Preschool Wheezers

Antecedentes: Los leucotrienos (LT), isoprostanos y nitritos/nitratos, que son biomarcadores de la inflamación de las vías aéreas, y el estrés oxidativo, pueden ser detectados en el condensado del aire exhalado (CAE). El objetivo de este estudio fue evaluar el LTB4, LTE4, 8-isoprostano, nitritos y nitratos en el CAE de niños preescolares sanos y con sibilancias. Material y métodos: Se realizó un estudio transversal en el que se incluyeron 21 niños sanos no atópicos y 25 pacientes con sibilancias recurrentes. El LTB4, LTE4 y 8-isoprostano, se midieron en el CAE mediante enzimoinmunoensayo, y los nitritos/nitratos mediante método colorimétrico. Resultados: Las concentraciones de LTB4 fueron mayores en los niños con episodios de sibilancias que en controles sanos (76 pg/ml vs 20 pg/ml, p<0,001); El LTE4 se incrementó también en niños con episodios de sibilancias en comparación con niños sanos (68 pg/ml vs 35 pg/ml, p<0,001). Las concentraciones de nitritos fueron mayores en los niños con episodios de sibilancias que en los controles (14 pg/ml vs 9,7 pg/ml, p<0,03). No hubo diferencias en las concentraciones de 8-isoprostano y nitratos entre el grupo de niños enfermos y el grupo control. Conclusiones: Nuestros hallazgos sugieren que el CAE es un método no invasivo para la evaluación de la inflamación de las vías respiratorias y del estrés oxidativo en lactantes y niños en edad preescolar. Las concentraciones de LTB4, LTE4 y de nitritos, se incrementaron en niños con episodios recurrentes de sibilancias en comparación con los controles sanos (AU)

Background: Leukotrienes (LT), isoprostanes, and nitrites/nitrates are biomarkers of airway inflammation and oxidative stress that can be detected in exhaled breath condensate (EBC). The aim of this study was to evaluate LTB4, LTE4, 8-isoprostane, and nitrite/nitrate levels in the EBC of healthy and wheezing preschool children. Methods: We included 21 healthy nonatopic children and 25 patients with recurrent wheezing episodes in a cross-sectional study. LTB4, LTE4, and 8-isoprostane concentrations were measured directly in EBC using a specific enzyme immunoassay; nitrite/nitrate concentrations were measured using a colorimetric assay. Results: LTB4 concentrations were higher in children with wheezing episodes than in healthy controls (76 pg/mL vs 20 pg/mL, P<.001). LTE4 was increased in children with wheezing episodes than in healthy controls (68 pg/mL vs 35 pg/mL, P<.001). Nitrite concentrations were higher in children with wheezing episodes than in healthy controls (14 pg/mL vs 9.7 pg/mL, P<.03). We found no differences in 8-isoprostane and nitrate concentrations between the patients and the healthy controls. Conclusions: Our findings suggest that EBC is a suitable noninvasive method for the assessment of airway inflammation and oxidative stress in preschool children. Levels of LTB4, LTE4, and nitrites were higher in children with recurrent wheezing episodes than in healthy controls (AU)

Ethanol steam reforming on Ni/Al2O3 catalysts: effect of the addition of Zn and Pt.

Ni-based catalysts supported on Zn-modified alumina were investigated in the ethanol steam reforming reaction. A commercial γ-alumina was impregnated with different amounts of zinc nitrate (0, 2, 5, 10, 15, 20 wt.% on Zn basis), calcined, and then impregnated with nickel nitrate aqueous solutions. The samples were characterized by a number of techniques: N(2) adsorption at 77 K, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray fluorescence (XRF), and temperature-programmed reduction (TPR). Their catalytic behavior in the ethanol steam reforming reaction was studied at 873 K, with a H(2)O/ethanol ratio of 5:1. Two effects of the presence of Zn were detected. On the one hand, zinc modifies the surface structure and the surface chemistry of the catalysts by formation of zinc aluminates, and on the other hand, zinc oxide can be reduced to metallic zinc under reaction conditions, thus modifying the catalytic properties of the active phase. The presence of Zn increases the ethanol conversion to gaseous compounds as compared with the catalyst supported on the Zn-free commercial alumina. The addition of a small amount of Pt (1 wt.%) causes a beneficial effect in the reaction. When Ni catalysts were used without a previous reduction treatment, ethylene was formed in high amounts; however, the Pt-Ni catalysts need no reduction pre-treatment to achieve high H(2) yields (close to 70%) and showed a high stability versus time on stream because of the control of the production of ethylene, a coke precursor.

Experimental strength of restorations with fibre posts at different stages, with and without using a simulated ligament.

The aim of this study was to analyse the strength and failure mode of teeth restored with fibre posts under retention and flexural-compressive loads at different stages of the restoration and to analyse whether including a simulated ligament in the experimental setup has any effect on the strength or the failure mode. Thirty human maxillary central incisors were distributed in three different groups to be restored with simulation of different restoration stages (1: only post, 2: post and core, 3: post-core and crown), using Rebilda fibre posts. The specimens were inserted in resin blocks and loaded by means of a universal testing machine until failure under tension (stage 1) and 50º flexion (stages 2-3). Half the specimens in each group were restored using a simulated ligament between root dentine and resin block and the other half did not use this element. Failure in stage 1 always occurred at the post-dentine interface, with a mean failure load of 191·2 N. Failure in stage 2 was located mainly in the core or coronal dentine (mean failure load of 505·9 N). Failure in stage 3 was observed in the coronal dentine (mean failure load 397·4 N). Failure loads registered were greater than expected masticatory loads. Fracture modes were mostly reparable, thus indicating that this post is clinically valid at the different stages of restoration studied. The inclusion of the simulated ligament in the experimental system did not show a statistically significant effect on the failure load or the failure mode.

Effect of recombinant growth hormone on leptin, adiponectin, resistin, interleukin-6, tumor necrosis factor-α and ghrelin levels in growth hormone-deficient children.

BACKGROUND: Treatment with GH promotes linear growth and decreases body fat in patients with isolated GH deficiency (GHD). However, few studies have analyzed how GH replacement modifies ghrelin levels and the adipokine profile and the relationship of these modifications with the metabolic changes. AIMS: To analyze the eventual differences between serum levels of leptin, leptin soluble receptor (sOBR), resistin, adiponectin, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), total (TG) and acylated ghrelin (AG) and lipid and glycemic profiles in children with GHD, as well as to determine the effect of GH replacement on these parameters during the first year of therapy. SUBJECTS AND METHODS: Thirty pre-pubertal (Tanner stage I) GHD children and 30 matched controls were enrolled. Children with GHD were studied before and after 6 and 12 months of GH treatment. Weight, height, BMI, fasting glucose, insulin, lipid profile and serum levels of adipokines and ghrelin were studied at every visit. Adi - pokines, insulin and ghrelin levels were determined by using commercial radio- and enzymoimmunoassays. RESULTS: At baseline children with GHD had significantly higher sOBR (p<0.01) and adiponectin (p<0.01) levels than controls. Treatment with GH resulted in a decline in leptin (p<0.05) and TG (p<0.001) levels, an increase of homeostasis model assessment index and restored IGF-I levels (p<0.001). CONCLUSIONS: These data indicate that GH replacement has a negative effect on leptin levels and may also produce a slight unfavorable effect on carbohydrate metabolism. In addition, the changes observed in the adipokine profile appear to be independent of body mass index.

Factors influencing age at diagnosis of primary ciliary dyskinesia in European children.

Primary ciliary dyskinesia (PCD) is a hereditary disorder of mucociliary clearance causing chronic upper and lower airways disease. We determined the number of patients with diagnosed PCD across Europe, described age at diagnosis and determined risk factors for late diagnosis. Centres treating children with PCD in Europe answered questionnaires and provided anonymous patient lists. In total, 223 centres from 26 countries reported 1,009 patients aged < 20 yrs. Reported cases per million children (for 5-14 yr olds) were highest in Cyprus (111), Switzerland (47) and Denmark (46). Overall, 57% were males and 48% had situs inversus. Median age at diagnosis was 5.3 yrs, lower in children with situs inversus (3.5 versus 5.8 yrs; p < 0.001) and in children treated in large centres (4.1 versus 4.8 yrs; p = 0.002). Adjusted age at diagnosis was 5.0 yrs in Western Europe, 4.8 yrs in the British Isles, 5.5 yrs in Northern Europe, 6.8 yrs in Eastern Europe and 6.5 yrs in Southern Europe (p < 0.001). This strongly correlated with general government expenditures on health (p < 0.001). This European survey suggests that PCD in children is under-diagnosed and diagnosed late, particularly in countries with low health expenditures. Prospective studies should assess the impact this delay might have on patient prognosis and on health economic costs across Europe.