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1.
AJNR Am J Neuroradiol ; 40(12): 2094-2101, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31727754

RESUMEN

BACKGROUND AND PURPOSE: The recently introduced Pipeline Flex Embolization Device with Shield Technology (Pipeline Shield) is the third generation of Pipeline flow-diverter devices. It has a new stent-surface modification, which reduces thrombogenicity. We aimed to evaluate clinical and radiographic (safety and efficacy) outcomes of the Pipeline Shield. MATERIALS AND METHODS: The 30-day and 1-year mortality and morbidity rates and the 6- and 18-month radiographic aneurysm occlusion outcomes for procedures performed between March 2016 and January 2018 were analyzed. 3D-TOF-MRA was used for follow-up. RESULTS: Forty-four attempted Pipeline Shield procedures were performed for 41 patients with 44 target aneurysms (total of 52 aneurysms treated). A total of 88.5% of devices were inserted in the anterior circulation, and 11.5%, in the posterior circulation; 49/52 (94.2%) aneurysms were saccular; and 1/52 (1.9%) was fusiform. One (1.9%) aneurysm was an iatrogenic pseudoaneurysm, and 1 (1.9%) was a dissecting aneurysm. Seventy-one percent (35/49) of the saccular aneurysms were wide-neck (neck, >4 mm), 34.6% (18/52) were large (≥10 mm), and 3.8% (2/52) were giant (≥25 mm). The mean aneurysm sac maximal diameter was 9.0 mm, and the mean neck width was 5.0 mm. The cumulative mortality and morbidity rates were 2.3% and 6.8% at 1 year, respectively. The adequate occlusion rate was 78.8% at 6 months and 90.3% at 18 months. CONCLUSIONS: In this pragmatic and non-industry-sponsored study, the occlusion rates and safety outcomes were similar to those seen in previously published studies with flow-diverter devices and earlier generation Pipeline Embolization Devices.


Asunto(s)
Prótesis Vascular , Embolización Terapéutica/instrumentación , Aneurisma Intracraneal/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Stents , Resultado del Tratamiento , Adulto Joven
2.
J Nanosci Nanotechnol ; 18(6): 3960-3968, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29442732

RESUMEN

A flower like cobalt oxide nanostructured thin film (Co2O3) on Nickel (Ni) plate as have been successfully developed via alcoholic Seed Layer assisted chemical bath Deposition (SLD) process. Through the controlled alkaline electrolytes, the flower and paddles like Co2O3 nanoarchitectures were formed. The prepared thin film was characterized by X-ray diffraction (XRD), scanning electron microscope with energy dispersive X-ray (SEM and EDX), Atomic Force Microscope (AFM), Raman spectroscopy techniques. Electron micrograph reveals the flower and paddles like nanostructured Co2O3 thin film deposited on Ni plates. The electrochemical characteristics were investigated using cyclic voltammetry (CV), charge-discharge and AC impedance spectroscopy in different aqueous electrolytes such as NaOH, KOH, and LiOH. The maximum specific capacitance of 856 Fg-1 was attained with 2 M KOH electrolyte with 2 mVs-1 of the Co2O3 thin film coated Ni plate at 80 °C using SLD method. The capacitance values obtained with various electrolytes are in the order of KOH > NaOH > LiOH. The results indicate that the present method is economical and the material is ecofriendly with enhanced capacitance property.

5.
Ann R Coll Surg Engl ; 94(4): 240-4, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22613301

RESUMEN

INTRODUCTION: A total of 17 cases of penetrating neck injury were managed by the otolaryngology team at King's College Hospital over a 3-year period in the 1980s. In April 2010 King's College Hospital became the major trauma centre for South East London. This prospective cohort study compares the incidence, changing demographic features and treatment outcomes of penetrating neck trauma in South East London over the previous 23 years. METHODS: Data were collected over a 12-month period (April 2010 to March 2011) and a selective management protocol was introduced to standardise initial investigations and further treatment. RESULTS: The past 23 years have seen a 550% increase in the incidence of penetrating neck injuries in South East London, with a marked increase in gun crime. Only 38% of cases underwent negative neck exploration in 2011 compared with 65% in 1987. Selective conservative management based on the absence of haemodynamic instability or radiological findings reduces length of hospital stay, lightens surgical workload and cuts costs without affecting morbidity or mortality. CONCLUSIONS: The increased incidence of penetrating neck injury is a reflection of more interpersonal violence rather than a consequence of the larger South East London trauma centre catchment area. Tackling this problem requires focus on wider issues of community prevention. Sharing of data between the four London trauma centres and the police is needed to help prevent interpersonal violence and develop a universal treatment algorithm for other institutions to follow.


Asunto(s)
Traumatismos del Cuello/epidemiología , Heridas Penetrantes/epidemiología , Adulto , Protocolos Clínicos , Femenino , Hematoma/etiología , Hematoma/terapia , Humanos , Incidencia , Puntaje de Gravedad del Traumatismo , Tiempo de Internación , Londres/epidemiología , Masculino , Traumatismos del Cuello/terapia , Grupo de Atención al Paciente/estadística & datos numéricos , Estudios Prospectivos , Centros Traumatológicos/estadística & datos numéricos , Resultado del Tratamiento , Heridas Penetrantes/terapia
6.
Pituitary ; 15(3): 276-87, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22076588

RESUMEN

Pituitary carcinoma occurs in ~0.2% of resected pituitary tumours and carries a poor prognosis (mean survival <4 years), with standard chemotherapy regimens showing limited efficacy. Recent evidence suggests that temozolomide (TMZ), an orally-active alkylating agent used principally in the management of glioblastoma, may also be effective in controlling aggressive/invasive pituitary adenomas/carcinomas. A low level of expression of the DNA-repair enzyme O6-methylguanine-DNA methyltransferase (MGMT) predicts TMZ responsiveness in glioblastomas, and a similar correlation has been observed in the majority of aggressive pituitary adenomas/carcinomas reported to date. Here, we report a case of a silent pituitary corticotroph adenoma, which subsequently re-presented with Cushing's syndrome due to functioning hepatic metastases. The tumour exhibited low immunohistochemical MGMT expression in both primary (pituitary) and secondary (hepatic) lesions. Initial TMZ therapy (200 mg/m² for 5 days every 28 days-seven cycles) resulted in marked clinical, biochemical [>50% fall in adrenocorticotrophic hormone (ACTH)] and radiological [partial RECIST (response evaluation criteria in solid tumors) response] improvements. The patient then underwent bilateral adrenalectomy. However, despite reintroduction of TMZ therapy (further eight cycles) ACTH levels plateaued and no further radiological regression was observed. We review the existing literature reporting TMZ efficacy in pituitary corticotroph tumours, and highlight the pointers/lessons for treating aggressive pituitary neoplasia that can be drawn from experience of susceptibility and evolving resistance to TMZ therapy in glioblastoma. Possible strategies for mitigating resistance developing during TMZ treatment of pituitary adenomas/carcinomas are also considered.


Asunto(s)
Dacarbazina/análogos & derivados , Neoplasias Hipofisarias/tratamiento farmacológico , Adenoma Hipofisario Secretor de ACTH/tratamiento farmacológico , Adenoma Hipofisario Secretor de ACTH/patología , Adenoma/tratamiento farmacológico , Anciano , Antineoplásicos Alquilantes/uso terapéutico , Dacarbazina/uso terapéutico , Resistencia a Antineoplásicos , Glioblastoma/tratamiento farmacológico , Humanos , Neoplasias Hepáticas/secundario , Masculino , O(6)-Metilguanina-ADN Metiltransferasa/metabolismo , Neoplasias Hipofisarias/patología , Neoplasias Hipofisarias/cirugía , Temozolomida
9.
Phys Med Biol ; 55(21): 6329-51, 2010 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-20938071

RESUMEN

Spline-based deformable registration methods are quite popular within the medical-imaging community due to their flexibility and robustness. However, they require a large amount of computing time to obtain adequate results. This paper makes two contributions towards accelerating B-spline-based registration. First, we propose a grid-alignment scheme and associated data structures that greatly reduce the complexity of the registration algorithm. Based on this grid-alignment scheme, we then develop highly data parallel designs for B-spline registration within the stream-processing model, suitable for implementation on multi-core processors such as graphics processing units (GPUs). Particular attention is focused on an optimal method for performing analytic gradient computations in a data parallel fashion. CPU and GPU versions are validated for execution time and registration quality. Performance results on large images show that our GPU algorithm achieves a speedup of 15 times over the single-threaded CPU implementation whereas our multi-core CPU algorithm achieves a speedup of 8 times over the single-threaded implementation. The CPU and GPU versions achieve near-identical registration quality in terms of RMS differences between the generated vector fields.


Asunto(s)
Algoritmos , Computadores , Procesamiento de Imagen Asistido por Computador/métodos , Gráficos por Computador , Humanos , Imagenología Tridimensional , Radiografía Torácica , Reproducibilidad de los Resultados , Programas Informáticos , Tomografía Computarizada por Rayos X
11.
Phys Med Biol ; 52(19): 5771-83, 2007 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-17881799

RESUMEN

This paper shows how to significantly accelerate cone-beam CT reconstruction and 3D deformable image registration using the stream-processing model. We describe data-parallel designs for the Feldkamp, Davis and Kress (FDK) reconstruction algorithm, and the demons deformable registration algorithm, suitable for use on a commodity graphics processing unit. The streaming versions of these algorithms are implemented using the Brook programming environment and executed on an NVidia 8800 GPU. Performance results using CT data of a preserved swine lung indicate that the GPU-based implementations of the FDK and demons algorithms achieve a substantial speedup--up to 80 times for FDK and 70 times for demons when compared to an optimized reference implementation on a 2.8 GHz Intel processor. In addition, the accuracy of the GPU-based implementations was found to be excellent. Compared with CPU-based implementations, the RMS differences were less than 0.1 Hounsfield unit for reconstruction and less than 0.1 mm for deformable registration.


Asunto(s)
Algoritmos , Intensificación de Imagen Radiográfica/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Técnica de Sustracción , Tomografía Computarizada Espiral/métodos , Fantasmas de Imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tomografía Computarizada Espiral/instrumentación
12.
Trop Anim Health Prod ; 35(2): 147-53, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12735705

RESUMEN

This paper reports the milk protein polymorphism, the allele frequencies of variants and the possible linkages among various combinations of milk protein phenotypes in the Kangayam cattle of south India. Milk samples from 156 Kangayam cows were typed by starch gel and polyacrylamide gel electrophoresis for caseins and whey proteins, respectively. All the four milk protein components studied, alpha(s)1-casein. beta-casein, beta-lactoglobulin and alpha-lactalbumin, exhibited polymorphism with high allele frequencies of 0.9231 +/- 0.0151 for alpha(s)1-casein C, 0.9263 +/- 0.0148 for beta-casein A, 0.9135 +/- 0.0159 for beta-lactoglobulin B and a relatively high frequency of 0.6218 +/- 0.0275 for alpha-lactalbumin A. The mean heterozygosity estimated over all the four milk protein loci was 0.2420. Genetic equilibrium was observed among all the loci studied, except alpha-lactalbumin. Linkage analysis confirmed the non-independence between alpha(s)1- and beta-caseins and between caseins and alpha-lactalbumin phenotypes.


Asunto(s)
Bovinos/genética , Proteínas de la Leche/genética , Animales , Caseínas/genética , Femenino , Frecuencia de los Genes/genética , Ligamiento Genético/genética , India , Lactalbúmina/genética , Lactoglobulinas/genética , Masculino , Polimorfismo Genético
13.
J Inorg Biochem ; 23(1): 1-11, 1985 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3981163

RESUMEN

Six new platinum complexes of the formula [Pt(2,2'-bipyridine)(amino acid)]n+, where n = 1 to 2 and amino acid is an anion of L-histidine, L-lysine, L-asparagine, L-phenylalanine, L-tryptophan, or L-tyrosine, have been prepared by interaction of [Pt(2,2'-bipyridine)Cl2] and an appropriate amino acid (sodium salt) in water or water-methanol mixture. They have been characterized by chemical analyses and spectral methods such as ultraviolet-visible, infrared, and 1H NMR spectroscopy. The 1H NMR studies of these complexes ascertain the modes of binding of amino acids to platinum. The histidine binds to platinum through the nitrogen of a -NH2 group and another nitrogen of heterocyclic ring. All other amino acids bind to platinum through nitrogen of a -NH2 group and oxygen of a -COO- group. The mode of binding of some amino acids to platinum in these complexes has been further confirmed by infrared spectroscopy, and the formulations of these complexes have been supported by conductivity measurements. These six amino acid complexes and also other complexes of glycine, alanine, leucine, serine, cysteine, methionine, and glutamine have shown growth inhibition against P-388 lymphocytic leukemic cells.


Asunto(s)
Aminoácidos/síntesis química , Antineoplásicos/síntesis química , Compuestos Organometálicos/síntesis química , Platino (Metal) , Aminoácidos/análisis , Aminoácidos/farmacología , Animales , Antineoplásicos/análisis , Fenómenos Químicos , Química , Química Física , Inhibidores de Crecimiento/farmacología , Leucemia P388/tratamiento farmacológico , Espectroscopía de Resonancia Magnética , Ratones , Ratones Endogámicos DBA , Compuestos Organometálicos/análisis , Compuestos Organometálicos/farmacología
14.
Trop Anim Health Prod ; 11(4): 227-30, 1979 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-552673

RESUMEN

Data on adult body weight of ewes belonging to Nali, Chokla breeds and their crosses (F1) with Rambouillet and Soviet Merino raised under semi-arid conditions in India were analysed. The ewes belonged to 5 distinct age groups ranging from 16.5 to 64 months. Nali and Chokla were significant lighter than all the 4 crossbred groups. There were no significant differences in body weight between crossbred groups except in the case of Soviet Merino x Chokla group which was the lightest and differed significantly from all other groups. Rambouillet crosses were heavier than Merino crosses but the difference was statistically significant only on Rambouillet x Chokla and Merino x Chokla. The improvement in body weight in crossbreds over native sheep ranged between 9.3 and 21.88%. The increase in live weight was significant only up to 49 months.


Asunto(s)
Peso Corporal , Clima , Ovinos/fisiología , Animales , Cruzamiento , Cruzamientos Genéticos , Femenino , India , Ovinos/genética , Especificidad de la Especie
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