Surface enhanced fluorescence effect improves the in vivo detection of amyloid aggregates.

The ß-amyloid (Aß) peptide is one of the key etiological agents in Alzheimer's disease (AD). The in vivo detection of Aß species is challenging in all stages of the illness. Currently, the development of fluorescent probes allows the detection of Aß in animal models in the near-infrared region (NIR). However, considering future applications in biomedicine, it is relevant to develop strategies to improve detection of amyloid aggregates using NIR probes. An innovative approach to increase the fluorescence signal of these fluorophores is the use of plasmonic gold nanoparticles (surface-enhanced fluorescence effect). In this work, we improved the detection of Aß aggregates in C. elegans and mouse models of AD by co-administering functionalized gold nanorods (GNRs-PEG-D1) with the fluorescent probes CRANAD-2 or CRANAD-58, which bind selectively to different amyloid species (soluble and insoluble). This work shows that GNRs improve the detection of Aß using NIR probes in vivo.

[Pediatric tracheostomy: Ten year experience in an Intensive Care Unit]. / Traqueostomía en niños: Experiencia de 10 años en una Unidad de Cuidados Intensivos Pediátricos.

INTRODUCTION: Pediatric tracheostomy indications have changed over the last 30 years, from acute and transient pro cedures secondary to airway obstruction to programmed tracheostomies indicated due to the need for chronic use of mechanical ventilation (MV). OBJECTIVE: To describe indications and morbidity associated with pediatric tracheostomies during a ten-year period. PATIENTS AND METHODS: Descrip tive study. Clinical records review of discharged patients (< 15 years old) tracheostomized during their hospital stay between 2005 and 2015. Demographic and clinical variables were evaluated before and after tracheostomy, stay in intensive care unit, age at the time of the tracheostomy, indication of tracheostomy, early complications (< 7 days), late complications (> 7 days), and mortality. RESULTS: 59 children with tracheostomy were analyzed, 36 (59%) tracheostomies were performed in children under 6 months, and 39 (60%) in males. 23 (39%) had a confirmed or under study genopathy and 25 (42%) had congenital heart disease. The main indications for tracheostomy were 58% secondary to airway disease and 42% due to chronic use of MV. Within the airway disease group, subglottic steno sis, vocal cord paralysis, and tracheobronchomalacia were the principal reasons for indication, and in the group of chronic use of MV, the main causes were bronchopulmonary dysplasia and chronic lung disease. We did not find tracheostomy-related mortality. 89% of the patients were discharged with tracheostomy and 59% with chronic use of MV. The probability of being discharged with a tracheos tomy was higher in younger patients while the chronic use of MV at discharge was higher in patients with a greater number of extubation failures before tracheostomy. CONCLUSION: Tracheostomy is a safe procedure in children, where the predominant causes of indication are airway disease and the need for chronic use of MV. Most children with tracheostomies are discharged with tracheostomy and chronic use of MV. Younger children, those with difficult weaning, confirmed or suspected ge nopathy, or special health needs are at greater risk of needing tracheostomy and chronic use of MV.

Plasmonic Nanoparticles as Optical Sensing Probes for the Detection of Alzheimer's Disease.

Alzheimer's disease (AD), considered a common type of dementia, is mainly characterized by a progressive loss of memory and cognitive functions. Although its cause is multifactorial, it has been associated with the accumulation of toxic aggregates of the amyloid-ß peptide (Aß) and neurofibrillary tangles (NFTs) of tau protein. At present, the development of highly sensitive, high cost-effective, and non-invasive diagnostic tools for AD remains a challenge. In the last decades, nanomaterials have emerged as an interesting and useful tool in nanomedicine for diagnostics and therapy. In particular, plasmonic nanoparticles are well-known to display unique optical properties derived from their localized surface plasmon resonance (LSPR), allowing their use as transducers in various sensing configurations and enhancing detection sensitivity. Herein, this review focuses on current advances in in vitro sensing techniques such as Surface-enhanced Raman scattering (SERS), Surface-enhanced fluorescence (SEF), colorimetric, and LSPR using plasmonic nanoparticles for improving the sensitivity in the detection of main biomarkers related to AD in body fluids. Additionally, we refer to the use of plasmonic nanoparticles for in vivo imaging studies in AD.

The Influence of Size and Chemical Composition of Silver and Gold Nanoparticles on in vivo Toxicity with Potential Applications to Central Nervous System Diseases.

The physicochemical and optical properties of silver nanoparticles (SNPs) and gold nanoparticles (GNPs) have allowed them to be employed for various biomedical applications, including delivery, therapy, imaging, and as theranostic agents. However, since they are foreign body systems, they are usually redistributed and accumulated in some vital organs, which can produce toxic effects; therefore, this a crucial issue that should be considered for potential clinical trials. This review aimed to summarize the reports from the past ten years that have used SNPs and GNPs for in vivo studies on the diagnosis and treatment of brain diseases and those related to the central nervous system, emphasizing their toxicity as a crucial topic address. The article focuses on the effect of the nanoparticle´s size and chemical composition as relevant parameters for in vivo toxicity. At the beginning of this review, the general toxicity and distribution studies are discussed separately for SNPs and GNPs. Subsequently, this manuscript analyzes the principal applications of both kinds of nanoparticles for glioma, neurodegenerative, and other brain diseases, and discusses the advances in clinical trials. Finally, we analyze research prospects towards clinical applications for both types of metallic nanoparticles.

[Cerebral sinovenous thrombosis in a newborn with mutation of MTHFR C677T treated with enoxaparin]. / Trombosis senovenosa cerebral en un recién nacido con mutación MTHFR C677T tratado con enoxaparina.

INTRODUCTION: Neonatal cerebral sinovenous thrombosis (CSNT) is a rare and generally serious con dition about which there is little knowledge of the responsible pathophysiological mechanisms and, although controversial, it has been suggested that genetic thrombophilia may play a role in its patho genesis. Out of concern for intracranial bleeding, the anticoagulant treatment with low-molecular- weight heparin is controversial. CLINICAL CASE: Full-term newborn who presented at eight days of life breastfeeding rejection, clonic seizures, and locomotor hypoactivity. The MRI neuroimaging showed a CSNT involving multiple venous sinuses, a right thalamic hemorrhagic infarction, and venous con gestion in frontal white matter. Thrombophilia study highlighted a homozygous MTHFR C677T mutation. Treatment with low-molecular-weight heparin was associated with repermeabilization of the superior sagittal sinus after 23 days of starting therapy. CONCLUSIONS: The clinical presentation of CSNT in the neonate is nonspecific, probably related to the extent and severity of the injury and the development of associated complications, such as venous hemorrhagic infarctions and intraparenchymal or intraventricular hemorrhage. These complications are detected through ultrasound or MRI, and they should make us suspect a CSNT. In this experience, the anticoagulant treatment proved to be safe and prevents thrombus propagation.

Trombosis senovenosa cerebral en un recién nacido con mutación MTHFR C677T tratado con enoxaparina / Cerebral sinovenous thrombosis in a newborn with mutation of MTHFR C677T treated with enoxaparin

Resumen: Introducción: La trombosis senovenosa cerebral neonatal (TSVC), es una patología rara y generalmente grave, de la cual se conoce poco sobre los mecanismos fisiopatológicos responsables y, aunque controvertido, se ha sugerido que la trombofilia genética, puede desempeñar un rol en la patogénesis. Debido a los temores de un sangrado intracraneal el tratamiento anticoagulante con heparina de bajo peso mole cular es controvertido. Objetivo: presentar un recién nacido con una trombosis senovenosa cerebral neonatal, discutir los factores de riesgo trombofílico, y el manejo con heparina de bajo peso molecu lar de la trombosis venosa cerebral. Caso Clínico: Recién nacido de término que debutó a los 8 días de vida con convulsiones clónicas, rechazo al pecho más hipoactividad motora. La neuroimagen con RM mostró una TSVC involucrando múltiples senos venosos, un infarto hemorrágico talámico dere cho y congestión venosa de la sustancia blanca frontal. El estudio de trombofilia puso de relieve una mutación homocigota del gen MTHFR C677T. El tratamiento con heparina de bajo peso molecular se asoció a repermeabilización del seno sagital superior a los 23 días de iniciada la terapia. Conclusio nes: La presentación clínica de la TSVC en el neonato es inespecífica, probablemente en relación con la extensión y gravedad de la lesión y el desarrollo de complicaciones asociadas, como infartos he morrágicos venosos intraparenquimatosos o hemorragia intraventricular. Estas complicaciones son detectables mediante Ecografia o Resonancia Magnética, y deben hacer sospechar una TSVC. En esta experiencia el tratamiento anticoagulante mostró ser seguro y prevenir la extensión de la trombosis.

Abstract: Introduction: Neonatal cerebral sinovenous thrombosis (CSNT) is a rare and generally serious con dition about which there is little knowledge of the responsible pathophysiological mechanisms and, although controversial, it has been suggested that genetic thrombophilia may play a role in its patho genesis. Out of concern for intracranial bleeding, the anticoagulant treatment with low-molecular- weight heparin is controversial. Objective: To present a case of a newborn with neonatal CSNT, to analyze the thrombophilic risk factors, and the management of cerebral venous thrombosis with low-molecular-weight heparin. Clinical Case: Full-term newborn who presented at eight days of life breastfeeding rejection, clonic seizures, and locomotor hypoactivity. The MRI neuroimaging showed a CSNT involving multiple venous sinuses, a right thalamic hemorrhagic infarction, and venous congestion in frontal white matter. Thrombophilia study highlighted a homozygous MTHFR C677T mutation. Treatment with low-molecular-weight heparin was associated with repermeabilization of the superior sagittal sinus after 23 days of starting therapy. Conclusions: The clinical presentation of CSNT in the neonate is nonspecific, probably related to the extent and severity of the injury and the development of associated complications, such as venous hemorrhagic infarctions and intraparenchymal or intraventricular hemorrhage. These complications are detected through ultrasound or MRI, and they should make us suspect a CSNT. In this experience, the anticoagulant treatment proved to be safe and prevents thrombus propagation.

[Breastfeeding, obesity and metabolic syndrome at school age]. / Lactancia materna, obesidad y síndrome metabólico en la edad escolar.

INTRODUCTION: Breastfeeding (BF) can be a protective factor against obesity and its associated metabolic complications. OBJECTIVE: To determine the association between breastfeeding history and present obesity, metabolic syndrome (MS) and insulin resistance (IR). PATIENTS AND METHODS: Cross-sectio nal study in 20 public schools in Santiago, Chile. Anthropometry and blood pressure were assessed. Blood lipids, glucose, insulin and HOMA index were measured in a fast blood sample. Parents answe red a survey on BF. MS was defined according to Cook's criteria and IR as HOMA > 90th percentile. Parents answered a survey about the antecedent of breastfeeding. Chi2 and Fischer tests were used (SSPS). RESULTS: 3,278 surveys were valid. Average age: 11.4 ± 1 years, 52.3% were female. Most of them (98.2%) were breasted, with a 15.9% prevalence of obesity versus 18.6% in the group that was not breastfed (p = 0.039). There was a non-significant trend of higher prevalence in MS and its components (except IR) in the non-breastfed group. The group breastfed from three to six months had a lower prevalence of obesity and MS components than the 0 to 3 months group ; the effect was the opposite when BF lsted longer than nine months. CONCLUSIONS: The prevalence of obesity was higher in children that did not received breastfeeding. A longer breastfeeding time during the first semester of life was associated with lower prevalence of obesity and metabolic complications.

Lactancia materna, obesidad y síndrome metabólico en la edad escolar / Breastfeeding, obesity and metabolic syndrome at school age

INTRODUCCIÓN: La lactancia materna (LM) puede ser un factor protector de la obesidad y sus complicaciones metabólicas. OBJETIVO: Determinar la asociación entre el antecedente de amamantamiento y la presencia de obesidad, síndrome metabólico (SM) y resistencia insulínica (RI). PACIENTES Y MÉTODOS: Estudio transversal en 20 escuelas públicas de Santiago, Chile. Se evaluó antropometría, presión arterial, perfil lipídico, glicemia, insulinemia e índice HOMA. Los padres respondieron una encuesta sobre el antecedente de LM. Se definió SM según criterios de Cook y RI como HOMA > percentil 90. RESULTADOS: Se recibieron 3.278 encuestas válidas. La edad promedio fue de 11,4 ± 1 años, siendo 52,3% mujeres. La mayoría (98,2%) recibió LM, con una prevalencia de 15,9% de obesidad versus 18,6% en los que no la recibieron (p = 0,039). Hubo una tendencia no significativa a que SM y sus componentes, excepto RI, fueran más prevalentes en el grupo no amamantado. Los escolares que recibieron LM por 3-6 meses presentaron una menor prevalencia de obesidad y de algunos componentes de SM que los que recibieron menor tiempo o no la recibieron; el efecto fue inverso cuando la LM se prolongó por más de 9 meses. CONCLUSIONES: La prevalencia de obesidad fue mayor en los escolares que no fueron amamantados. Durante el primer semestre, la LM de mayor duración se asoció a menor prevalencia de obesidad y complicaciones metabólicas.

INTRODUCTION: Breastfeeding (BF) can be a protective factor against obesity and its associated metabolic complications. OBJECTIVE: To determine the association between breastfeeding history and present obesity, metabolic syndrome (MS) and insulin resistance (IR). PATIENTS AND METHODS: Cross-sectio nal study in 20 public schools in Santiago, Chile. Anthropometry and blood pressure were assessed. Blood lipids, glucose, insulin and HOMA index were measured in a fast blood sample. Parents answe red a survey on BF. MS was defined according to Cook's criteria and IR as HOMA > 90th percentile. Parents answered a survey about the antecedent of breastfeeding. Chi2 and Fischer tests were used (SSPS). RESULTS: 3,278 surveys were valid. Average age: 11.4 ± 1 years, 52.3% were female. Most of them (98.2%) were breasted, with a 15.9% prevalence of obesity versus 18.6% in the group that was not breastfed (p = 0.039). There was a non-significant trend of higher prevalence in MS and its components (except IR) in the non-breastfed group. The group breastfed from three to six months had a lower prevalence of obesity and MS components than the 0 to 3 months group ; the effect was the opposite when BF lsted longer than nine months. CONCLUSIONS: The prevalence of obesity was higher in children that did not received breastfeeding. A longer breastfeeding time during the first semester of life was associated with lower prevalence of obesity and metabolic complications.

The relationship between inflammation and remodeling in childhood asthma: A systematic review.

OBJECTIVES: We aimed to perform a systematic review of all studies with direct measurements of both airway inflammation and remodeling in the subgroup of children with repeated wheezing and/or persistent asthma severe enough to warrant bronchoscopy, to address whether airway inflammation precedes remodeling or is a parallel process, and also to assess the impact of remodeling on lung function. METHODS: Four databases were searched up to June 2017. Two independent reviewers screened the literature and extracted relevant data. RESULTS: We found 526 references, and 39 studies (2390 children under 18 years old) were included. Airway inflammation (eosinophilic/neutrophilic) and remodeling were not present in wheezers at a mean age of 12 months, but in older pre-school children (mean 2.5 years), remodeling (mainly increased reticular basement membrane [RBM] thickness and increased area of airway smooth muscle) and also airway eosinophilia was reported. This was worse in school-age children. RBM thickness was similar in atopic and non-atopic preschool wheezers. Airway remodeling was correlated with lung function in seven studies, with FeNO in three, and with HRCT-scan in one. Eosinophilic inflammation was not seen in patients without remodeling. There were no invasive longitudinal or intervention studies. CONCLUSION: The relationship between inflammation and remodeling in children cannot be determined. Failure to demonstrate eosinophilic inflammation in the absence of remodeling is contrary to the hypothesis that inflammation causes these changes. We need reliable, non-invasive markers of remodeling in particular if this is to be addressed.

Anterior abdominal wall parasitic leiomyoma: case report.

The leiomyomas are a common gynecologic entity that may present unusual growth patterns or unusual locations. Its atypical presentations creates a diagnostic challenge. This is a case report of a parasitic leiomyoma located in the anterior abdominal wall in a 53 years old woman with pelvic compressive and urinary symptoms, with no history of any gynecological surgery. This case illustrates the diagnostic difficulties and describes the complementary images used in the preoperative evaluation.

Efficacy and safety of misoprostol, dinoprostone and Cook's balloon for labour induction in women with foetal growth restriction at term.

BACKGROUND AND OBJECTIVES: To compare effectiveness and safety of dinoprostone, misoprostol and Cook's balloon as labour-inducing agents in women with intrauterine growth restriction (IUGR) at term. METHODS: Retrospective cohort chart review of women diagnosed with foetal growth restriction at term in Reina Sofia Hospital, Cordoba, Spain from January 2014 to December 2015. Registration of baseline characteristics and method of induction was made. The main outcome was time from induction to delivery. Obstetric and perinatal outcomes were also collected. RESULTS: A total of 99 women were diagnosed with IUGR in the mentioned period. Of them, 21 women were induced with dinoprostone [dinoprostone group (DG)], 20 with misoprostol (MG) and in 58 with Cook's balloon (CG). Groups were homogeneous regarding pre-induction Bishop score and parity. The CG required more time (24.36 vs. 19.23 h; p = 0.02) and more oxytocin dose for conduction of labour from induction to delivery (6.75 vs. 1.24 mUI; p < 0.01) than DG. Moreover, the CG also needed more oxytocin than MG, 6.75 vs. 2.37 mUI (p < 0.001). Caesarean rate was 5, 14.9 and 17.3% in MG, DG and CG, respectively. No differences were observed in rates of uterine tachysystole, non-reassuring foetal status and neonatal adverse events. INTERPRETATION AND CONCLUSIONS: Prostaglandins were more effective than Cook's balloon to induce labour and achieve vaginal birth in this sample of women with IUGR at term, with a similar safety profile.

Comparison of the catalytic activity for O2 reduction of Fe and Co MN4 adsorbed on graphite electrodes and on carbon nanotubes.

We have compared the electrocatalytic activity of several substituted and unsubstituted Co and Fe N4-macrocyclic complexes (MN4) for the electro-reduction of oxygen with the complexes directly adsorbed on the edge plane of pyrolytic graphite or adsorbed on carbon nanotubes (CNTs). In the presence of CNTs, one order of magnitude higher surface concentrations of MN4 catalysts per geometric area unit could be adsorbed leading to a lower overpotential for the oxygen electro-reduction and activities in the same order of magnitude as the commercially available Pt/C catalysts in basic pH. From Koutecky-Levich regression analysis, the total number of electrons transferred was approximately 2 for all the Co complexes and 4 for all the Fe ones, both in the presence and in the absence of the carbon nanotubes. Furthermore, the Tafel slopes did not vary due to the presence of the CNTs and presented values in the range of -0.06 V decade-1 for the CoN4 compounds and in the range of -0.04 V decade-1 for FeN4. When plotting the log of kinetic current densities (i.e. log jk) at a constant potential for each complex divided by the surface concentration Γ, and the number of electrons transferred n for the ORR for each catalyst, versus the difference between the redox potential of the metal active site of the Co(ii)/(i) or Fe(iii)/(ii) catalyst and the reversible potential of the reaction they promote, the catalytic activity increases when the formal potential of the complex becomes more positive and the data obtained with complexes adsorbed on graphite are in agreement with the data obtained when using CNTs indicating that the increase in jk when CNTs are present is only due to an increase in the number of active sites per geometric area of the electrode.

What can we do to reduce the associated costs in induction of labour of intrauterine growth restriction foetuses at term? A cost-analysis study.

OBJECTIVE: To evaluate the costs associated with induction of labour in intrauterine growth restriction fetuses comparing different procedures. STUDY DESIGN: 150 pregnancies at term diagnosed with intrauterine growth restriction and indication for induction of labour were included. 24 were ripened with misoprostol 25 µg tablets, 24 with dinoprostone 10 mg vaginal insert, and 77 with Cook® cervical ripening balloon. To determine the costs of induction of labour, method of induction, intrapartum medication, epidural analgesia, type of delivery, and maternal and neonatal admissions were considered. Statistical analysis was performed using the G-Stat 2.0 free statistical software. ANOVA test was used for comparisons between quantitative parametric variables. Chi-squared test or Fisher test was used for qualitative variables. A value of p < 0.05 was considered statistically significant. RESULTS: Up to 70.83% women in dinoprostone group gave birth within the first 24 h compared to 42.66% in misoprostol group and 36.36% in CG (p < 0.01). Misoprostol tablets were cheaper (9.45 ± 1.52 US dollars) than dinoprostone or Cook® balloon (41.67 ± 0 and 59.85 ± 0 54.45 ± 0 US dollars, respectively) (p < 0.01). Costs related to maternal admissions were higher in CG (475.13 ± 146.95$) than dinoprostone group (475.13 ± 146.95$) or MG (427.97 ± 112.65$) (p = 0.03). Total costs in misoprostol group (2765.18 ± 495.38$) were lower than in the dinoprostone group (3075.774 ± 896.14$) or Cook® balloon group (3228.02 ± 902.06$) groups. CONCLUSIONS: Misoprostol for induction of labour had lower related costs than dinoprostone or Cook® balloon, with similar obstetrical and perinatal outcomes.

Local hormone therapy for genitourinary syndrome of menopause in breast cancer patients: is it safe?

The genitourinary syndrome of menopause (GSM) is a frequent complaint among breast cancer (BC) survivors that lead to an important affection of their quality of life (QoL). Lifestyle measures such as smoking cessation or regular sexual activity are usually insufficient to significantly improve GMS and although therapies such as lubricants and polycarbophil moisturized gels are considered first-line therapies to alleviate symptoms of vulvovaginal atrophy, these non-hormonal options are not able to reverse atrophy once it occurs. Instead, this complaint is corrected by local estrogens. The estrogen vaginal treatment usually used to treat GSM, is an issue of concern in this group due to the possible negative effect over the BC outcomes. On the other hand, the worsening of QoL in these patients due to symptoms related to GSM can lead to discontinuation of hormone adjuvant therapies and therefore must be addressed properly. The goal of this review is to contribute to health care professionals to make an informed decision to care for their BC patients.

Vaginal misoprostol and cervical ripening balloon for induction of labor in late-term pregnancies.

AIM: The aim of this study was to compare vaginal misoprostol with the Cook cervical ripening balloon (CCRB) for induction of labor in late-term nulliparous women. METHODS: This open, quasi-experimental, prospective study included 109 nulliparous women with late-term pregnancies and Bishop scores < 7. Fifty-five women were allocated to receive vaginal misoprostol 25 mcg and 54 received the CCRB to induce labor. The primary outcome was the time until delivery. Secondary outcomes included time to the onset of labor and obstetric and perinatal outcomes. RESULTS: Women in the misoprostol group experienced shorter time until delivery (25.41 h vs 31.26 h; P < 0.01) and in a greater percentage gave birth within the first 24 h. Time to active stage of labor was 19.5 h and 23.8 h (P < 0.01) for misoprostol and the CCRB, respectively. There were no differences in the rates of cesarean section or post-partum anemia. Additionally, there were no differences in rates of tachysystolia, intrapartum fever, or meconium. Perinatal outcomes, post-partum pH, Apgar scores, and neonatal admissions were similar in the two groups. CONCLUSION: Misoprostol 25 mcg reduces labor induction time compared with the CCRB with similar safety in late-term pregnancies.

Use of hormone therapy for menopausal symptoms and quality of life in breast cancer survivors. Safe and ethical?

Breast cancer is the most prevalent cancer in women and presently, the breast cancer survivors are an important group of women that faced the several consequences of estrogen deficiency, which is especially common in women after chemotherapy. The most bothersome is the vasomotor symptoms, which are effectively relieved by hormonal therapy (HT). Also, the increased risk of osteoporosis and coronary artery disease is major problem to be resolved in pos of maintaining a good quality of life. Fearing cancer recurrence, most physicians do not offer HT to women with a history of breast cancer. Over this issue reviews the available evidence of the use of HT and tibolone in women treated for breast cancer.

Sexuality and quality of life in congenital hypogonadisms.

Turner syndrome and idiopathic congenital hypogonadism including Kallmann syndrome are conditions associated to a large number of widely known comorbidities that need a medical support forever. One of the characteristics shared by both conditions is the lack of sexual development that influencing the sexuality functioning and quality of life of the affected women. Few studies have been conducted to assess these topics, but they need to be considered in the treatment to all women with hypogonadism. This review on the major medical issues and psychological aspects, also focus in the present knowledge about sexual function and quality of life of women with Turner syndrome and idiopathic congenital hypogonadism, which aims to help in the comprehensive management of these patients.

Binding of Trivalent Arsenic onto the Tetrahedral Au20 and Au19Pt Clusters: Implications in Adsorption and Sensing.

The interaction of arsenic(III) onto the tetrahedral Au20 cluster was studied computationally to get insights into the interaction of arsenic traces (presented in polluted waters) onto embedded electrodes with gold nanostructures. Pollutant interactions onto the vertex, edge, or inner gold atoms of Au20 were observed to have a covalent character by forming metal-arsenic or metal-oxygen bonding, with adsorption energies ranging from 0.5 to 0.8 eV, even with a stable physisorption; however, in aqueous media, the Au-vertex-pollutant interaction was found to be disadvantageous. The substituent effect of a platinum atom onto the Au20 cluster was evaluated to get insights into the changes in the adsorption and electronic properties of the adsorbent-adsorbate systems due to chemical doping. It was found that the dopant atom increases both the metal-pollutant adsorption energy and stability onto the support in a water media for all interaction modes; adsorption energies were found to be in a range of 0.6 to 1.8 eV. All interactions were determined to be accompanied by electron transfer as well as changes in the local reactivity that determine the amount of transferred charge and a decrease in the HOMO-LUMO energy gap with respect to the isolated substrate.

[Prevalence of sudden death syndrome among children]. / Síndrome de muerte súbita del lactante: prevalencia y cambios en los últimos años en Chile.

BACKGROUND: The sudden infant's death syndrome (SD) is the leading cause of death in children under one year. Despite advances in its study, the pathogenesis has not been yet fully elucidated. AIM: To assess the prevalence of SD in Chilean infants and its changes in recent years. MATERIAL AND METHODS: Review of birth and death databases of the Ministry of Health from 1997 to 2009. All cases diagnosed as SD, according to the lnternational Classification of Diseases, 10th edition, were selected. A demographic analysis was performed and mortality rates for each year were calculated. RESULTS: We identified 1442 cases of SD (847 males, 517 deaths at home). The median age of death was 2 months (0 to 11.0 months). Ninety six percent of deaths occurred in children aged <6 months. Mortality rate for SD was 0.45/1000 live births. There was a 23% reduction between 1997 and 2009. When analyzing geographic distribution, more cases were found in the Southern latitudes of the country. CONCLUSIONS: The overall rate of SD in Chile is higher than in European countries and in North America. The observed decrease in cases over the years is still far from optimal.

Síndrome de muerte súbita del lactante: prevalencia y cambios en los últimos años en Chile / Prevalence of sudden death syndrome among children

Background: The sudden infant's death syndrome (SD) is the leading cause of death in children under one year. Despite advances in its study, the pathogenesis has not been yet fully elucidated. Aim: To assess the prevalence of SD in Chilean infants and its changes in recent years. Material and Methods: Review of birth and death databases of the Ministry of Health from 1997 to 2009. All cases diagnosed as SD, according to the lnternational Classification of Diseases, 10th edition, were selected. A demographic analysis was performed and mortality rates for each year were calculated. Results: We identified 1442 cases of SD (847 males, 517 deaths at home). The median age of death was 2 months (0 to 11.0 months). Ninety six percent of deaths occurred in children aged <6 months. Mortality rate for SD was 0.45/1000 live births. There was a 23% reduction between 1997 and 2009. When analyzing geographic distribution, more cases were found in the Southern latitudes of the country. Conclusions: The overall rate of SD in Chile is higher than in European countries and in North America. The observed decrease in cases over the years is still far from optimal.