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1.
J Mater Sci Mater Med ; 25(2): 555-60, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24154920

RESUMO

Twenty orthodontic archwires with 55.2% Ni and 44.8% Ti (% weight) were subjected to a dipping treatment to coat the NiTi surface by a polyamide polymer. It has been selected a Polyamide 11 due to its remarkable long lasting performance. The transformation temperatures as well as the transformation stresses of the NiTi alloy were determined in order to know whether the coating process can alter its properties. The adhesive wear tests have been demonstrated that the wear rates as well as the dynamic friction coefficients µ of polymer coated wires are much lower than metallic wires. The corrosion studies have shown that the use of this polymer, as coating, seals the NiTi surface to prevent corrosion and the release of nickel ions. The average decrease of Ni ions release due to this coating is around 85%.


Assuntos
Ligas de Cromo , Materiais Revestidos Biocompatíveis , Nylons , Fios Ortodônticos , Varredura Diferencial de Calorimetria , Corrosão , Elasticidade
2.
J Mater Sci Mater Med ; 24(5): 1327-32, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23440428

RESUMO

The aim of this paper is to analyze the influence of the nature of the orthodontic archwires on the friction coefficient and wear rate against materials used commonly as brackets (Ti-6Al-4V and 316L Stainless Steel). The materials selected as orthodontic archwires were ASI304 stainless steel, NiTi, Ti, TiMo and NiTiCu. The array archwire's materials selected presented very similar roughness but different hardness. Materials were chosen from lower and higher hardness degrees than that of the brackets. Wear tests were carried out at in artificial saliva at 37 °C. Results show a linear relationship between the hardness of the materials and the friction coefficients. The material that showed lower wear rate was the ASI304 stainless steel. To prevent wear, the wire and the brackets have high hardness values and in the same order of magnitude.


Assuntos
Análise de Falha de Equipamento , Fricção/fisiologia , Fios Ortodônticos , Saliva Artificial/farmacologia , Ligas Dentárias/química , Análise do Estresse Dentário , Dureza/efeitos dos fármacos , Humanos , Desenho de Aparelho Ortodôntico , Aço Inoxidável/química , Propriedades de Superfície/efeitos dos fármacos , Titânio/química
3.
Acta Clin Belg ; 77(1): 118-121, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32543299

RESUMO

BACKGROUND: Weiss-Kruszka syndrome (WSKA) is a rare disorder caused by mutations in the ZNF462 gene or deletion of 9p31.2 chromosome region, involving ZNF462. The prevalence of WSKA is unknown as only 24 affected individuals have been described. This syndrome should be suspected in individuals presenting mild global developmental delay and common craniofacial abnormalities. CASE PRESENTATION: We presented a case of an infant, 3 years and 4-month life who presented pondostatural and psychomotor retardation, generalized hypotonia with hypermobility, bilateral palpebral ptosis, epicanthal folds, and poorly expressive facies as the main clinical features. These characteristics lead to the realization of genetics studies that resulted in the identification of a novel mutation c.3306dup; p.(Gln1103Thrfs*10) in ZNF462. CONCLUSIONS: WSKA should be suspected in individuals presenting mild global developmental delay, ptosis, downslanting palpebral fissures, exaggerated Cupid's Bow, arched eyebrows, epicanthal folds and short upturned nose with a bulbous tip. Hypertrophy of the ventricular septum and severe OSA were described in our patient and should be considered in future reviews of the disease. This case is added to the reduced number of publications previously reported regarding WSKA and contributes to understanding the genetic characteristics, clinical features, and diagnosis of this syndrome.Abbreviations: WSKA: Weiss-Kruszka syndrome; CP: craniofacial perimeter; WES: whole-exome sequencing; RSV: respiratory syncytial virus; OSA: obstructive sleep apnoea; ACMG: American College of Medical Genetics and Genomics.


Assuntos
Anormalidades Craniofaciais , Proteínas de Ligação a DNA/genética , Fácies , Humanos , Lactente , Hipotonia Muscular , Mutação , Proteínas do Tecido Nervoso/genética , Síndrome , Fatores de Transcrição/genética
4.
An Pediatr (Barc) ; 71(1): 31-7, 2009 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-19464968

RESUMO

OBJECTIVE: To determine management practices of minor head trauma in children evaluated at Spanish Hospital Emergency Departments and to determine patient variables associated with intracranial injury. METHODS: Multicenter and prospective study during 18 months in 9 hospitals in Spain. Patients up to the age of 18 years with minor head trauma (Glasgow Coma Scale score higher than or equal to 13 on admission), treated in Emergency Departments and with a maximum onset of 72h since the traumatism, were included in the study. RESULTS: A total of 1070 patients were studied with a median age of 2.4 years (p25-75 0.9-6.4 years); 61.2% were male. The median time between head trauma and medical consultation was 1 hour (p25-75 0.6-2.5h). Skull X-rays were performed on 64.5% of the children and a head CT scan on 9%; 91.4% of X-ray and 84.4% of CT were normal. The prevalence of intracranial injury was 1.4% (95% CI: 0.8-2.3). Twenty-five point three percent of the patients were admitted; 4 (3.7%) required neurosurgical intervention during admission. None of the patients died. Multiple logistic regression analysis identified loss of consciousness (OR 4.2, 95% CI: 1.1-17; P=0.045), neurological deterioration (OR 8.8, 95% CI: 2.1-37.6; P=0.003) and cephalhaematoma (OR 14.6, 95% CI: 4.9-44; P <0.001) as independent predictors of intracranial injury. CONCLUSIONS: The combination of clinical parameters allows selection of patients with minor head trauma who need complementary explorations. In consequence, the routine use of skull X-ray in their initial evaluation is unnecessary.


Assuntos
Lesões Encefálicas/epidemiologia , Sistema de Registros , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Escala de Gravidade do Ferimento , Masculino , Estudos Prospectivos , Espanha
5.
Nutr Hosp ; 20(3): 204-9, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-15989067

RESUMO

OBJECTIVES: To study the macronutrients intake in Soria teenagers from 10 to 19 years, as well as their body mass index (BMI). METHODS: A seven-day diet questionnaire filled in by an accidental sample of teenagers (54 boys and 56 girls) from public schools in the capital. Working out the average daily intake of energy, carbohydrates, lipids and proteins by the software of "Alimentación y Salud" which also gives values of individual recommended dietary allowances (RDAs) related to each individual's particular characteristics. Use of Student's t-test to compare the average values of the estimated intakes of different nutrients and their RDAs. RESULTS: In general, the intakes of energy, proteins and lipids are statistically significant over the RDAs, while the carbohydrates intake is under the recommendations. With reference to the type of lipids, the intake is over the RDAs for cholesterol, monounsaturated fatty acids, and saturated fatty acids, but not for polyunsaturated fatty acids. Among girls from 13 years of age more than 12% have a higher BMI than 26 kg/m2, but between 10 and 12 years of age more than 20% of the students have this parameter under 16 kg/m2. CONCLUSIONS: According to the results, it would be useful to implement some nutritional intervention among the adolescents in Soria capital to promote a healthy feeding in order to avoid possible disorders (obesity, anorexia, etc.).


Assuntos
Dieta , Ingestão de Energia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Espanha , Inquéritos e Questionários
6.
Bioelectrochemistry ; 60(1-2): 81-6, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12893313

RESUMO

The action of electromagnetic fields (EMF) on different pathways related to cell physiology, proliferation, toxicity of chemicals, gene expression, etc., are currently being investigated although the results are still not conclusive and even conflicting. In laboratory and animal studies, EMF has been found to produce a great variety of effects such as: increase in ornithine decarboxylase activity in breast, increase in beta-galactosidase gene expression and oncogene transcription after exposure to 50/60 Hz. Animal studies have shown that the use of EMF can enhance drug delivery across biological barriers (rat abdominal skin), using benzoic acid as the drug candidate. It has been reported by different authors that pulsed EMF (PEMF) can produce alterations in antineoplastic drugs potency. In the present study, we investigated the effects of PEMF on methotrexate cytotoxicity in MCF-7 breast cancer cells and the effects with simultaneous exposure to FeCl3. The data presented in the current report indicate that PEMF (25 Hz, 1.5 mT) do not induce modulation of the action of methotrexate (with and without iron-III) in MCF-7 cells when they are exposed to PEMF for 2 h/day during 3 days.


Assuntos
Neoplasias da Mama/patologia , Compostos Férricos/toxicidade , Magnetismo , Metotrexato/toxicidade , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cloretos , Humanos
7.
An Pediatr (Barc) ; 80(4): 242-8, 2014 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-23849728

RESUMO

OBJECTIVES: To describe epidemiological characteristics, types of injury, prognosis and medical management of bicycle-related Paediatric Emergency Department (ED) visits and to identify potential preventive measures. PATIENTS AND METHODS: This multicentred, observational prospective study included all children between 3 and 16 years of age treated for bicycle-related injuries in the Emergency Departments of 15 Spanish Hospitals belonging to the «Unintentional Paediatric Injury Workshop¼ of the Spanish Paediatric Emergency Society between the 1(st) of June 2011 and the 31(st) of May 2012. Characteristics of all ED visits, as well as epidemiological data and accident-related information, were collected. RESULTS: A total of 846 patients were included in the study, with a male predominance (72.9%) and a median age of 9.6 ± 3.6 years. Head injury was the third most common injury (22.3%) and the main cause of admission to the Pediatric Intensive Care Unit (PICU) (68.4%). More than three-quarters (77.9%) of the patients did not wear a helmet, which was significantly associated to a higher incidence of head injury and admission to PICU. Older children (OR 1.063) and bicycle injuries involving motor vehicles (OR 2.431) were identified as independent risk factors for worse outcomes. CONCLUSIONS: Since helmet use reduces up to 88% of central nervous system lesions secondary to head injury, promotion of its use should be the main preventive measure, followed by restriction of bike-riding to cycling areas.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Ciclismo/lesões , Adolescente , Criança , Pré-Escolar , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Estudos Prospectivos , Espanha , Ferimentos e Lesões/epidemiologia , Ferimentos e Lesões/terapia
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