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1.
Nat Commun ; 10(1): 256, 2019 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-30635571

RESUMO

The original version of this Article contained an error in the Acknowledgements, which incorrectly omitted from the end the following: 'The research leading to these results has received funding from the European Community's Horizon 2020 Framework Programme under grant agreement nº 730872.' This has been corrected in both the PDF and HTML versions of the Article.

2.
Nat Commun ; 9(1): 4145, 2018 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297775

RESUMO

A fundamental understanding of ion charge storage in nanoporous electrodes is essential to improve the performance of supercapacitors or devices for capacitive desalination. Here, we employ in situ X-ray transmission measurements on activated carbon supercapacitors to study ion concentration changes during electrochemical operation. Whereas counter-ion adsorption was found to dominate at small electrolyte salt concentrations and slow cycling speed, ion replacement prevails for high molar concentrations and/or fast cycling. Chronoamperometry measurements reveal two distinct time regimes of ion concentration changes. In the first regime the supercapacitor is charged, and counter- and co-ion concentration changes align with ion replacement and partially co-ion expulsion. In the second regime, the electrode charge remains constant, but the total ion concentration increases. We conclude that the initial fast charge neutralization in nanoporous supercapacitor electrodes leads to a non-equilibrium ion configuration. The subsequent, charge-neutral equilibration slowly increases the total ion concentration towards counter-ion adsorption.

3.
Nanoscale ; 9(31): 11249-11260, 2017 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-28753215

RESUMO

Determining the in situ 3D nano- and microscale strain and reorientation fields in hierarchical nanocomposite materials is technically very challenging. Such a determination is important to understand the mechanisms enabling their functional optimization. An example of functional specialization to high dynamic mechanical resistance is the crustacean stomatopod cuticle. Here we develop a new 3D X-ray nanostrain reconstruction method combining analytical modelling of the diffraction signal, fibre-composite theory and in situ deformation, to determine the hitherto unknown nano- and microscale deformation mechanisms in stomatopod tergite cuticle. Stomatopod cuticle at the nanoscale consists of mineralized chitin fibres and calcified protein matrix, which form (at the microscale) plywood (Bouligand) layers with interpenetrating pore-canal fibres. We uncover anisotropic deformation patterns inside Bouligand lamellae, accompanied by load-induced fibre reorientation and pore-canal fibre compression. Lamination theory was used to decouple in-plane fibre reorientation from diffraction intensity changes induced by 3D lamellae tilting. Our method enables separation of deformation dynamics at multiple hierarchical levels, a critical consideration in the cooperative mechanics characteristic of biological and bioinspired materials. The nanostrain reconstruction technique is general, depending only on molecular-level fibre symmetry and can be applied to the in situ dynamics of advanced nanostructured materials with 3D hierarchical design.

4.
Phys Chem Chem Phys ; 19(23): 15549-15561, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28581546

RESUMO

A new carbon model derived from in situ small-angle X-ray scattering (SAXS) enables a quantitative description of the voltage-dependent arrangement and transport of ions within the nanopores of carbon-based electric double-layer capacitors. In the first step, ex situ SAXS data for nanoporous carbon-based electrodes are used to generate a three-dimensional real-space model of the nanopore structure using the concept of Gaussian random fields. This pore model is used to derive important pore size characteristics, which are cross-validated against the corresponding values from gas sorption analysis. In the second step, simulated in situ SAXS patterns are generated after filling the model pore structure with an aqueous electrolyte and rearranging the ions via a Monte Carlo simulation for different applied electrical potentials. These simulated SAXS patterns are compared with in situ SAXS patterns recorded during voltage cycling. Experiments with different cyclic voltammetry scan rates revealed a systematic time lag between ion transport processes and the applied voltage signal. Global transport into and out of nanopores was found to be faster than the accommodation of the local equilibrium arrangement in favor of sites with a high degree of confinement.

5.
Sci Rep ; 6: 26249, 2016 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-27211574

RESUMO

The complex hierarchical structure in biological and synthetic fibrous nanocomposites entails considerable difficulties in the interpretation of the crystallographic texture from diffraction data. Here, we present a novel reconstruction method to obtain the 3D distribution of fibres in such systems. An analytical expression is derived for the diffraction intensity from fibres, explaining the azimuthal intensity distribution in terms of the angles of the three dimensional fibre orientation distributions. The telson of stomatopod (mantis shrimp) serves as an example of natural biological armour whose high impact resistance property is believed to arise from the hierarchical organization of alpha chitin nanofibrils into fibres and twisted plywood (Bouligand) structures at the sub-micron and micron scale. Synchrotron microfocus scanning X-ray diffraction data on stomatopod telson were used as a test case to map the 3D fibre orientation across the entire tissue section. The method is applicable to a range of biological and biomimetic structures with graded 3D fibre texture at the sub-micron and micron length scales.


Assuntos
Quitina/química , Exoesqueleto/química , Exoesqueleto/ultraestrutura , Animais , Quitina/ultraestrutura , Simulação por Computador , Crustáceos/química , Imageamento Tridimensional , Microscopia Eletrônica de Varredura , Modelos Moleculares , Nanocompostos/química , Nanocompostos/ultraestrutura , Nanofibras/química , Nanofibras/ultraestrutura , Síncrotrons , Difração de Raios X
6.
Cir Pediatr ; 28(3): 123-127, 2015 Jul 20.
Artigo em Espanhol | MEDLINE | ID: mdl-27775305

RESUMO

OBJECTIVE: To compare the results of laparoscopic versus open adhesiolysis in children affected by postoperative bowel obstruction. METHODS: Retrospective study reviewing charts of all patients who were operated on due to postoperative adhesions in our Department. Demographic data, clinical characteristics and postoperative data were collected. RESULTS: During the last 8 years, 37 patients were operated on for postoperative intestinal obstructions. 40.5% were operated by laparoscopy and 59.5% by laparotomy. Mean ages were 6.31 and 4.32 years in laparoscopic and open groups, respectively. There were no differences in days of evolution of the occlusion, neither in their medical history. Patients in laparoscopic group had better outcomes in the need of central lines (15% vs 61.90% p= 0.012), use of parenteral nutrition (38.46% vs 83.33% p= 0.005), beginning of the enteral nutrition (4.04 vs 8.17 days p= 0.004) and hospital stay (7.77 vs 13.05 days p= 0.027). CONCLUSIONS: Open and laparoscopic adhesiolysis are effective to treat adhesive cases. Laparoscopic adhesiolysis has some advantages over open surgery: less need of central lines and parenteral nutrition, earlier start of enteral nutrition, less rate of complications and shorter hospital stay.


OBJETIVO: Comparar los resultados de la adhesiolisis laparoscópica frente a la técnica abierta en niños con oclusiones postoperatorias. METODO: Estudio retrospectivo de los pacientes intervenidos por oclusiones postoperatorias en nuestro centro. Se recogieron variables demográficas, las características clínicas del paciente y del cuadro oclusivo y los resultados postoperatorios. RESULTADOS: En los últimos 8 años, se han realizado 37 intervenciones por oclusiones intestinales postoperatorias: un 40,5% mediante laparoscopia y un 59,5% mediante laparotomía. La media de edad fue 6,31 y 4,32 años para la técnica laparoscópica y abierta, respectivamente. No encontramos diferencias en el tiempo de evolución del cuadro oclusivo, ni en los antecedentes quirúrgicos. Sin embargo, el grupo de adhesiolisis laparoscópica presentó mejores resultados que el de cirugía abierta en: necesidad de vía central (15% frente a 61,90% p= 0,012), uso parenteral (38,46% frente a 83,33% p= 0,005), reinicio de la nutrición enteral (4,04 días frente a 8,17 p= 0,004) y estancia postoperatoria (7,77 frente a 13,05 días p= 0,027). CONCLUSIONES: Ambos abordajes son eficaces para la resolución de la oclusión. La adhesiolisis laparoscópica aporta ventajas frente a la cirugía abierta: menor necesidad de vía central y de nutrición parenteral, reinicio precoz de la nutrición enteral y menor estancia hospitalaria.

7.
Cir Pediatr ; 25(2): 61-5, 2012 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-23113390

RESUMO

BACKGROUND: Withdrawal of central venous catheters (CVCs) is usually a simple surgical procedure. However, in some cases, the catheter is stuck in the vessel wall and its removal is not possible if more invasive interventions are not performed. MATERIAL AND METHODS: We performed a retrospective study from 2003 to 2011 of patients who were clearing a CVC and the factors that could have intervened in the removal impossibility. We compared the type of catheter, the insertion site, the time between its insertion and removal, the primary diagnosis and the treatment. In addition, a monitoring by clinical and imaging tests has been made in patients with retained CVCs. RESULTS: An amount of 174 interventions were carried out. In 5 cases the CVC could not been removed. These 5 cases were patients diagnosed with ALL B and were treated with identical chemotherapy treatment. In addition, at the time of its retirement, all the patients had the CVC for a period longer than 2 years -29 to 84 months-. In patients with retained fragments, no complication arose from this condition. The mean follow-up period was 36 months -maximum 48 months-. CONCLUSIONS: The potential complications arising from the presence of the retained CVCs fragments include infection, venous thrombosis and catheter migration. Based on our results, we propose that a conservative management might be considered as an option in these patients.


Assuntos
Cateteres Venosos Centrais/efeitos adversos , Corpos Estranhos/terapia , Adolescente , Criança , Pré-Escolar , Remoção de Dispositivo , Falha de Equipamento , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos
8.
J Phys Condens Matter ; 24(28): 284112, 2012 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-22738928

RESUMO

The effect of repeated cycles of water adsorption/desorption on the structural stability of ordered mesoporous silica SBA-15 is studied by small-angle x-ray scattering (SAXS). In situ sorption measurements are conducted using a custom-built sorption apparatus in connection with a laboratory SAXS setup. Two striking irreversible changes are observed in the sorption isotherms as derived from the integrated SAXS intensity. First, the capillary condensation pressure shifts progressively to lower relative pressure values with increasing number of sorption cycles. This effect is attributed to chemisorption of water at the silica walls, resulting in a change of the fluid-wall interaction. Second, the sorption cycles do not close completely at vanishing vapour pressure, suggesting that progressively more water remains trapped within the porous material after each cycle. This effect is interpreted to be the result of an irreversible collapse of parts of mesopores, originating from pore wall deformation due to the large Laplace pressure of water acting on the pore walls at capillary condensation and capillary evaporation.

9.
Phys Chem Chem Phys ; 14(11): 3852-8, 2012 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22327805

RESUMO

A simple explanation is given for the low-temperature density minimum of water confined within cylindrical pores of ordered nanoporous materials of different pore size. The experimental evidence is based on combined data from in-situ small-angle scattering of X-rays (SAXS) and neutrons (SANS), corroborated by additional wide-angle X-ray scattering (WAXS). The combined scattering data cannot be described by a homogeneous density distribution of water within the pores, as was originally suggested from SANS data alone. A two-step density model reveals a wall layer covering approximately two layers of water molecules with higher density than the residual core water in the central part of the pores. The temperature-induced changes of the scattering signal from both X-rays and neutrons are consistent with a minimum of the average water density. We show that the temperature at which this minimum occurs depends monotonically on the pore size. Therefore we attribute this minimum to a liquid-solid transition of water influenced by confinement. For water confined in the smallest pores of only 2 nm in diameter, the density minimum is explained in terms of a structural transition of the surface water layer closest to the hydrophilic pore walls.

10.
Oncogene ; 31(38): 4196-206, 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-22231442

RESUMO

Estrogen effects on mammary epithelial and breast cancer (BC) cells are mediated by the nuclear receptors ERα and ERß, transcription factors that display functional antagonism with each other, with ERß acting as oncosuppressor and interfering with the effects of ERα on cell proliferation, tumor promotion and progression. Indeed, hormone-responsive, ERα+ BC cells often lack ERß, which when present associates with a less aggressive clinical phenotype of the disease. Recent evidences point to a significant role of microRNAs (miRNAs) in BC, where specific miRNA expression profiles associate with distinct clinical and biological phenotypes of the lesion. Considering the possibility that ERß might influence BC cell behavior via miRNAs, we compared miRNome expression in ERß+ vs ERß- hormone-responsive BC cells and found a widespread effect of this ER subtype on the expression pattern of these non-coding RNAs. More importantly, the expression pattern of 67 miRNAs, including 10 regulated by ERß in BC cells, clearly distinguishes ERß+, node-negative, from ERß-, metastatic, mammary tumors. Molecular dissection of miRNA biogenesis revealed multiple mechanisms for direct regulation of this process by ERß+ in BC cell nuclei. In particular, ERß downregulates miR-30a by binding to two specific sites proximal to the gene and thereby inhibiting pri-miR synthesis. On the other hand, the receptor promotes miR-23b, -27b and 24-1 accumulation in the cell by binding in close proximity of the corresponding gene cluster and preventing in situ the inhibitory effects of ERα on pri-miR maturation by the p68/DDX5-Drosha microprocessor complex. These results indicate that cell autonomous regulation of miRNA expression is part of the mechanism of action of ERß in BC cells and could contribute to establishment or maintenance of a less aggressive tumor phenotype mediated by this nuclear receptor.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Receptor beta de Estrogênio/metabolismo , Estrogênios/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Linhagem Celular Tumoral , Cromatina/metabolismo , Análise por Conglomerados , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Ribonuclease III/metabolismo
11.
J Struct Biol ; 171(2): 133-41, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20438848

RESUMO

Nano-crystallite deformation of cellulose microfibrils in the secondary cell wall layer of spruce wood tracheids was observed during de- and rehydration experiments below the fibre saturation point. A quantitative analysis of the (004), (200) and the (110)/(11 0) doublet X-ray diffraction peaks revealed longitudinal contraction, lateral expansion and changes in the monoclinic angle of the cellulose unit cell during drying of wood fibres. Experiments on unfixed samples as well as the simultaneous application of mechanical tensile and dehydration stress to samples hold at constant length showed two deformation mechanisms of different nature and magnitude. The first mechanism depends on the relative wood moisture content and the second one on the macroscopic tensile stress. These findings imply a new perspective on the role of water adsorption perceiving a hydration-induced structural change of cellulose crystal structure as a major driving force for deformation.


Assuntos
Parede Celular/química , Parede Celular/metabolismo , Celulose/química , Celulose/metabolismo , Microfibrilas/química , Microfibrilas/metabolismo , Picea/química , Picea/metabolismo , Difração de Raios X
12.
Cir Pediatr ; 23(4): 201-5, 2010 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-21520550

RESUMO

INTRODUCTION: There has been an important evolution of surgical treatment in recent years due to the progressive generalization of laparoscopic surgery. All of the available techniques can be done laparoscopically with similar results to those of open surgery. In 1978, Villet et al. described the Dumping syndrome (DS) as a frequent complication of Nissen fundoplication. DS is a group of signs and symptoms that appear shortly after surgery, including abdominal pain, paleness, sweating, diarrhea, nausea, even weight loss. These symptoms can be differentiated into early dumping that occurs between 30 to 60 minutes after eating and late dumping that occurs 92-240 minutes after the postprandial period. MATERIAL AND METHODS: A total of 8 patients (3 boys and 5 girls) have been studied. Their ages ranged from 3 to 12 years (mean 9 years), and they were diagnosed of dumping syndrome after performing the laparoscopic Nissen-Rossetti. All underwent a gastric voiding study by scintigraphy after administration of a volume of milk adjusted to their weight labeled with 99Tc-DTPA and oral glucose overload test with 1.75 g/kg of glucose, determining the baseline glycemia and every 30 minutes post-intake, at 0, 30 and 90 minutes. Insulin was also measured to obtain the glucose/insulin ratio. This study was conducted for all patient diagnosed of dumping syndrome before and after laparoscopic Nissen-Rossetti surgery. RESULTS: The following results were obtained: Glucose Curve: 1. Maximum glycemia. PreNissen. The mean of the maximum glycemia values before surgery was 133.9+/-32.11 mg/dl. Post-Nissen. Mean maximum glycemias after surgery was 208.5 +/- 45.07 mg/dl with a range of 147-276 mg/dl. These differences of maximum glycemia were clearly significant with a p <0.002. Minimum glycemia. The mean value of the minimum glycemias after the surgery, compared with the previous value, did not show significant differences: 62.6+/- 11.51 mg/dl versus 71.8 +/- 28.04 mg/dl. Glucose/insulin ratio. The hyperinsulinism values after the intervention studied by means of the glucose/insulin ratio were abnormal in 70.5% (defined as ratio under 3). The mean value was also characteristic of hyperinsulinism (2.3 +/- 1.62). The mean value of the coefficient prior to the surgery was 4.6 with a deviation of 3.04, the differences not being statistically significant with a p= 0.097. Measurement of gastric voiding: The T1/2 (decay) value in post-Nissen patients was significantly lower than in pre-Nissen patients. The postsurgical mean and standard deviation was 29.74 +/- 7.92 min, while in the presurgical group, the mean and standard deviation was 73.75 +/- 28.34 min with p< 0.011; statistically significant. CONCLUSIONS: From the values obtained, we can state that a significant increase in maximum glycemia has been found in all children after surgery who were diagnosed of dumping syndrome and a significant decrease in the mean time of gastric voiding and therefore an increase in the acceleration of gastric voiding after the performance of the Nissen regarding the previous values. The dumping syndrome is a frequent side effect that we must keep in mind in patients who have been previously operated for anti-reflex surgery, the symptoms being greater in most of the transitory cases. Furthermore, it is important to keep in mind because it has an easy treatment that reverts the symptoms in a short time


Assuntos
Glicemia/análise , Síndrome de Esvaziamento Rápido/sangue , Síndrome de Esvaziamento Rápido/fisiopatologia , Fundoplicatura/efeitos adversos , Esvaziamento Gástrico , Laparoscopia , Criança , Pré-Escolar , Síndrome de Esvaziamento Rápido/etiologia , Feminino , Fundoplicatura/métodos , Humanos , Masculino
13.
Cir Pediatr ; 21(1): 27-31, 2008 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-18444387

RESUMO

The tumors of the salivary glands are infrequent in children, and parotid gland is involved in 80% of them. When a salivary gland tumor is present, the chance of malignancy is greater in the child than in the adult. We reviewed 8 cases identified in patients aged 14 years and younger in our hospital, analyzing its antecedents, signs and symptoms, histological features, diagnosis, treatment and evolution. All the patients displayed preauricular painless, non-inflammatory and slow-growing masses to an age between 10 months and 14 years. Four or them were pleomorphic adenomas, two haemangiomas, one epidermal cysts and one myoepithelial carcinoma. We emphasize the exceptional nature of the carcinoma for its rareness and for the high degree of malignancy expressed. We made a fine needle aspiration biopsy in four cases but they were conclusive only in three. All were treated by surgical resection of the tumour except for the myoepithelial carcinoma and the recurrent pleomorphic adenoma that were treated by total parotidectomy. The malignant tumours of the parotid gland are clinically indistinguishable of the benign ones, thus when any palpable mass appears in the zone of the parotid gland, an accurate diagnosis should be made without delay. The treatment of choice is the surgical excision with wide margins, being other adjuvant treatments less useful to this age than in the adult age.


Assuntos
Neoplasias Parotídeas , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Neoplasias Parotídeas/diagnóstico , Neoplasias Parotídeas/cirurgia
14.
Cir Pediatr ; 20(3): 183-7, 2007 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-18018749

RESUMO

INTRODUCTION: Endoscopic dilatation using a high pressure balloon is a widely used technique for the treatment of strictures of the urinary tract secondary to surgery in adult patient. Several studies have evaluated its usage in the treatment of primary and secondary strictures of the urinary tract of child with a disparity of results. GOAL: Evaluate Effectiveness and Safetiness of high pressure balloon dilatation and double "J" implantation in the treatment of postsurgical strictures of urinary tract in children. PATIENTS AND METHODS: Retrospective study of endoscopic dilatation of secondary to surgery strictures performed in our unit during the last past 18 months. Demographical data, surgical records, symptoms, renal function, dilatation technique, postsurgery complications and ultrasonography and isotopic data (pre and post dilatation) were evaluated. RESULTS: Six children, aged 13 months-9 years (media = 4.3 years) were treated in our unit. Four presented ureteropelvic junction obstruction (UPO) after Anderson-Hynes pyeloplasty and 2 vesico-ureteral junction stenosis (VUO) in 3 reimplants units, (one with Cohen tecnique and two with Politano tecnique). All 6 patients showed dilatation of urinary tract and isotopic diuretic renogram prior to dilatation that showed for all cases an obstructed pattern with T1/2 > 20 minutes. Two of the children presented lumbar pain and one of them had suffered an urine infection. Time interval between surgery and dilatation varied between 23 and 118 months. Surgical technique used for all cases was high pressure retrograde balloon dilatation and placement of double "J" before retrograde pielography. In all patients a double J catheter was implanted and left in place for 4 to 9 weeks. Technical inability to place the catheter after the expansion forced to the accomplishment of a percutaneus nephrostomy echo guided in one case. One of the children showed hematuria up to 7 days after dilatation procedure. Hospilatization varied between 24 hours to 10 days being (moda = 3 days). The patient that needed nephrostomy underwent ulterior sucessful dilatation 4 months after first procedure. The 2 children presenting vesico-ureteral junction stricture underwent calibration 10 and 12 months after dilatation, showing both good caliber. Diuretic renogram curve Improvement was confirmed for all patients but one of the VUO children that showed renal function deterioration after dilatation procedure. Lumbar pain disappear for both 2 children that had referred it. CONCLUSIONS: Endoscopic dilatation of strictures of urinary tract using balloon in children that were previously sommeted to surgical interventions is technically available and shows good results in the short-medium term with low index of post procedural complications, so, it should be considered as initial treatment for these patients.


Assuntos
Cateterismo , Pelve Renal , Obstrução Ureteral/terapia , Criança , Pré-Escolar , Humanos , Lactente , Masculino , Estudos Retrospectivos , Obstrução Ureteral/etiologia , Procedimentos Cirúrgicos Urológicos/efeitos adversos
15.
Actas Urol Esp ; 30(1): 93-4, 2006 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-16703738

RESUMO

The paraurethral cyst or Skene's duct cyst is a rare congenital anomaly in the female newborn. It appears like a round, yellow or orange-colored cystic mass on either side of the urethral meatus. The reported incidence is 1 in 2.000 to 7.000 female births. The low frequency of the Skene's duct cyst and the little awareness of it and its benignity may lead to wrong diagnosis that underestimates its incidence. There are authors that agree with surgical treatment of paraurethral cyst to obtain an early resolution, even though a majority agrees to manage conservatively.


Assuntos
Cistos/diagnóstico , Doenças Uretrais/diagnóstico , Feminino , Humanos , Recém-Nascido
16.
Cir Pediatr ; 19(4): 201-3, 2006 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-17352107

RESUMO

Cloacal exstrophy is a complex multisistemic anomaly that involves gastrointestinal and genitourinary issues. The aim of our paper is to report our experience in dealing with genital reconstruction and faecal and urinary continence in patients with female cloacal anomalies. We reviewed the clinical records from the three patients we have achieved a final reconstruction. We recorded the surgical management and both functional and anatomic results. The three of them required a bladder neck closure associated with a continent stoma, they are dry with intermittent catheterization and free of upper urinary complications. Genital reconstruction required a unique plan for each one, according to their anatomy and their cosmetic desires. One of the patients reported satisfactory sexual intercourse. Management of patients with cloacal exstrophy has major concerns about urinary and fecal continence and about genital reconstruction and function. Knowing the long-term results may help to develop management strategies and improve counselling for patients who have under-gone reconstruction.


Assuntos
Extrofia Vesical/cirurgia , Cloaca/anormalidades , Bexiga Urinária/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos , Adolescente , Criança , Feminino , Humanos , Procedimentos de Cirurgia Plástica/métodos , Resultado do Tratamento , Bexiga Urinária/anormalidades
17.
Phys Rev Lett ; 95(22): 225501, 2005 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-16384230

RESUMO

Single carbon fibers are deformed in bending by forming loops with varying radius. Position-resolved x-ray diffraction patterns from the bent fibers are collected from the tension to the compression region with a synchrotron radiation nanobeam of 100 nm size from a waveguide structure. A strain redistribution with a shift of the neutral axis is observed. A significant increase of the misorientation of the graphene sheets in the compression region shows that intense buckling of the nanosized carbon crystallites is the physical origin of different tensile and compressive properties.

18.
Cir Pediatr ; 18(3): 132-5, 2005 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-16209374

RESUMO

AIMS: Analysis of main factors of spinal cord and vertebral column injuries in our environment. METHODS: We reviewed the data collected from the patients (n = 2640) admitted to our hospital because of trauma and included in our Registry from January 1995 to April 2002. Among this group, 86 patients (3.3%) had spinal cord and vertebral column injuries and were included in the study. RESULTS: Group gender distribution was 45 males and 41 females. In our group, 71 patients suffered vertebral fractures, 3 of them with spinal cord injuries (4.2%), 13 patients with vertebral subluxation, 11 of them between C1-C2, and 2 patients with spinal cord injury without radiographic abnormality. Only 71 patients, 4.9% of the total of the patients who were admitted with any type of fracture (n=1457), suffered vertebral fractures. These patients suffered 130 vertebral fractures, 35 of them (49.3%) suffered multiple fractures. Thoracic vertebrae were the most frequently affected (n=82, 63%). The most frequent localization was T4 toT8 (n=50, 38.5% and T11 to L2 (n=41, 31.5%). Age ranged between 12 and 15 years (n=35, 49.3%), with only 5 patients under 6 years. 90.9% of the patients with lumbar fractures were older than 8 years and 76.9% of the patients with cervical fractures were over 8 years. Motor vehicle accident was the most common cause in our series (n=20, 23.3%). 81% of these patients did not use safety belt. Ten children with cervical injuries were seen by medical staff at the prehospital stage, and only 4 of them arrived to Hospital with cervical collar. There were thirty five patients with thoracic or lumbar injuries but only 27 of them were transferred to our Institution by ambulance. Surgery was required in 2 patients, both of them with unstable fractures. Mean hospital stay was 17,1 days (range 2-37 days). CONCLUSIONS: Group gender distribution is similar between males and females and the incidence in our series is higher than other series of the literature. Thoracic injuries are the most frequent. It is necessary to improve prehospital management of these patients and to increase the use of safety belt. Spine injury incidence increased with age.


Assuntos
Traumatismos da Medula Espinal/epidemiologia , Traumatismos da Coluna Vertebral/epidemiologia , Adolescente , Distribuição por Idade , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Espanha/epidemiologia
19.
Eur J Pediatr Surg ; 15(1): 30-7, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15795825

RESUMO

OBJECTIVES: To analyse the characteristics of the infant population suffering trauma in our setting. To evaluate the importance of the different aetiological mechanisms. To study the pre- and intra-hospital management of these children. To describe the relative significance of the different lesions. To establish the magnitude of paediatric trauma as a social problem in terms of morbidity and mortality. MATERIAL AND METHODS: From January 1995 to April 2002, a total of 2633 children admitted to our Centre (Hospital Universitario Gregorio Maranon) after suffering some type of injury were included in our Trauma Register. 108 variables have been analysed, including the identification of the patient, type, site and mechanism of the accident, pre-hospital care, transport, complete evaluation on admission, indices of injury severity, diagnostic tests, lesions, treatments performed and morbidity and mortality. RESULTS: The accidents were more frequent in boys than in girls (68.5 % versus 31.5 %). The predominant age group was the 12 - 15 year old group (36.8 %). There was a higher frequency of accidents in the street (37.2 %) than at home (19.4 %) or at school (13.8 %). The most frequent mechanism was a fall (35.6 %), followed by road traffic accidents (23.7 %). On admission, 14.7 % of the children had a Paediatric Trauma Score (P.T.S.) < or = 8 (n = 388). 3.8 % were considered severe multiple trauma patients, presenting an Injury Severity Score (I.S.S.) > or = 15 (n = 101). 4.2 % of the children required intensive care. The most frequent lesions were those of the locomotor system (58.1 %) and head injuries (34.9 %). Some type of surgical or orthopaedic procedure was performed under general anaesthesia in 1522 patients (57.8 %). The mean length of stay was 4.4 days (range 1 - 214 days). Sequelae of some form were detected in 36.4 % of the patients over 3 years of age. The total mortality was 0.5 % (n = 13), being 12.8 % in the group of patients with an I.S.S. > or = 15. CONCLUSIONS: Analysis of the data in our Registry has helped us to define the characteristics of the paediatric trauma population in our setting, to monitor the management of trauma in the different care levels and to develop prevention programmes. It has also enabled us to compare the results with those of other centres in terms of morbidity and mortality with the aim of identifying and correcting any possible deficiencies in the care system.


Assuntos
Acidentes/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Adolescente , Distribuição por Idade , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Sistema de Registros , Espanha/epidemiologia
20.
Cir Pediatr ; 17(4): 164-70, 2004 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-15559201

RESUMO

INTRODUCTION: Congenital sternal cleft is a rare malformation. Little more than one hundred cases have been published, and rarely more than two cases are published in a single publication. We present five new cases that show the entire spectrum of defects. METHODS: They were 3 males and 2 females. Age range between 1 day and 5 years of age. There were 2 supraxiphoid clefts (SC), 2 gladiolar defects and 1 xiphoid cleft. We evaluate the demographics, associated malformations, mode of treatments and results. RESULTS: The SC were not associated to congenital herat malformations, but with a many other malformative spectrum (anterior cervical web, hemangiomatosis, CNS malformations, coloboma and pectus excavatum). The two females had SC and were operated on the 24th and 30th days of age. The first one developed a superior vena cava síndrome for a few days after surgery and a moderate pectus excavatum that did not required surgery. A midline cervical web was also surgically repaired at 10 years of age. The second patient with SC was treated with interferon alfa-2a and local infiltration of corticosteroid for treatment of hemangiomatosis. Both patients had excellent final results (follow up 11 and 5 years respectively). Gladiolar clefts were observed durign surgical repair of congenital Herat malformations (ventricular septal defect and partial anomalous of pulmonary venous draninage). They were repaired by direct closure of the defect. The patient with the xiphoid cleft had associaed a Cantrell pentalogy. He died 4 days after operation because of extreme prematurity and pulmonary vascular hypertenion. CONCLUSIONS: 1) We have observed five new cases of sternal cleft. 2) Each anatomical variety had their own mode of presentation, a different malformative spectrum and clinical evolution that are based on a distinct embryonic origin. 3) Excluding the xiphoid clefts, the long term surviving is 100%, but they are associated with a great variety of other congenital defects.


Assuntos
Esterno/anormalidades , Esterno/cirurgia , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino
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