RESUMEN
PURPOSE: Intracanal rib head penetration is a well-known entity in dystrophic scoliotic curves in neurofibromatosis type 1. There is potential for spinal cord injury if this is not recognised and managed appropriately. No current CT-based classification system is currently in use to quantify rib head penetration. This article aims to propose and evaluate a novel CT-based classification for rib head penetration primarily for neurofibromatosis but which can also be utilised in other conditions of rib head penetration. MATERIALS AND METHODS: The grading was developed as four grades: normal rib head (RH) position-Grade 0, subluxed extracanal RH position-Grade 1, RH at pedicle-Grade 2, intracanal RH-Grade 3. Grade 3 was further classified depending on the head position in the canal divided into thirds. Rib head penetration into proximal third (from ipsilateral side)-Grade 3A, into the middle third-Grade 3B and into the distal third-Grade 3C. Seventy-five axial CT images of Neurofibromatosis Type 1 patients in the paediatric age group were reviewed by a radiologist and a spinal surgeon independently to assess interobserver and intraobserver agreement of the novel CT classification. Agreement analysis was performed using the weighted Kappa statistic. RESULTS: There was substantial interobserver correlation with mean Kappa score (k = 0.8, 95% CI 0.7-0.9) and near perfect intraobserver Kappa of 1.0 (95% CI 0.9-1.0) and 0.9 (95% CI 0.9-1.0) for the two readers. CONCLUSION: The novel CT-based classification quantifies rib head penetration which aids in management planning.
Asunto(s)
Neurofibromatosis 1 , Escoliosis , Niño , Humanos , Costillas/diagnóstico por imagen , Columna Vertebral , Tomografía Computarizada por Rayos XRESUMEN
The management of spinal deformity in children with univentricular cardiac pathology poses significant challenges to the surgical and anaesthetic teams. To date, only posterior instrumented fusion techniques have been used in these children and these are associated with a high rate of complications. We reviewed our experience of both growing rod instrumentation and posterior instrumented fusion in children with a univentricular circulation. Six children underwent spinal corrective surgery, two with cavopulmonary shunts and four following completion of a Fontan procedure. Three underwent growing rod instrumentation, two had a posterior fusion and one had spinal growth arrest. There were no complications following surgery, and the children undergoing growing rod instrumentation were successfully lengthened. We noted a trend for greater blood loss and haemodynamic instability in those whose surgery was undertaken following completion of a Fontan procedure. At a median follow-up of 87.6 months (interquartile range (IQR) 62.9 to 96.5) the median correction of deformity was 24.2% (64.5° (IQR 46° to 80°) vs 50.5° (IQR 36° to 63°)). We believe that early surgical intervention with growing rod instrumentation systems allows staged correction of the spinal deformity and reduces the haemodynamic insult to these physiologically compromised children. Due to the haemodynamic changes that occur with the completed Fontan circulation, the initial scoliosis surgery should ideally be undertaken when in the cavopulmonary shunt stage.
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Algoritmos , Procedimiento de Fontan , Escoliosis/cirugía , Adolescente , Pérdida de Sangre Quirúrgica , Clavos Ortopédicos , Niño , Puente Cardíaco Derecho , Hemodinámica , Humanos , Atención Perioperativa/métodos , Estudios Retrospectivos , Fusión Vertebral/instrumentación , Fusión Vertebral/métodos , Resultado del TratamientoRESUMEN
BACKGROUND: This study evaluated the short-term and long-term effects of the angiotensin II type 1 receptor antagonist candesartan cilexetil on hemodynamics, neurohormones, and clinical symptoms in patients with congestive heart failure (CHF). METHODS: In this multicenter, double-blind, parallel-group study, 218 patients with CHF (New York Heart Association class II or III) with impaired left ventricular function (ejection fraction < or =40%) and pulmonary capillary wedge pressure > or =13 mm Hg were randomly assigned to 12 weeks of treatment with placebo (n = 44) or candesartan cilexetil (2 mg [n = 45], 4 mg [n = 46], 8 mg [n = 39], or 16 mg [n = 44]) once daily after a 2-week placebo run-in period. Hemodynamic measurements were performed by right heart catheterization over a 24-hour period after single (day 1) and repeated (3-month) treatment with the study drug. RESULTS: On regression analysis of the time-response curves, single and multiple doses of candesartan cilexetil produced sustained, significant, and dose-dependent reductions in pulmonary capillary wedge pressure (short-term effect P =.036, long-term effect P =.035) and mean pulmonary arterial pressure (short-term effect P =.031, long-term effect P =.042). Systemic vascular resistance showed a trend toward decreasing with dose on short-term and long-term treatments. No consistent changes were seen in cardiac index. Compensatory increases in plasma renin activity and angiotensin II levels with decreases in aldosterone and atrial natriuretic peptide were dose-dependent and significant. Candesartan cilexetil improved clinical symptoms, stabilized patient New York Heart Association status compared with placebo, and was judged to be an efficacious treatment by the investigators. More patients receiving placebo stopped the trial prematurely because of an adverse event than in any candesartan cilexetil group, and there was no excess of deaths in any treatment group. Candesartan was safe and well tolerated at all dosages. CONCLUSIONS: Candesartan cilexetil demonstrated significant short-term and long-term improvements in hemodynamic, neurohormonal, and symptomatic status and was well tolerated in patients with CHF.
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Bencimidazoles/uso terapéutico , Compuestos de Bifenilo/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Hemodinámica/efectos de los fármacos , Hormonas/sangre , Tetrazoles , Adolescente , Adulto , Anciano , Aldosterona/sangre , Angiotensina II/sangre , Antagonistas de Receptores de Angiotensina , Factor Natriurético Atrial/sangre , Bencimidazoles/farmacología , Compuestos de Bifenilo/farmacología , Método Doble Ciego , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Placebos , Profármacos/farmacología , Profármacos/uso terapéutico , Análisis de Regresión , Renina/sangre , Resultado del TratamientoRESUMEN
Mechanical stabilisation of pathological fractures of the sacrum is technically challenging. There is often inadequate purchase in the sacrum, and stabilisation has to be achieved between the lumbar vertebrae and ilium. We present a simplification of the Galveston technique. We treated a total of six patients with this technique, four for metastatic disease and two for primary tumours. Our technique consists of the formation of a proximal stable construct using ISOLA pedicle screws linked distally using a modular system of connectors to threaded iliac bolts with cross linkages. Neurological decompression and fusion was performed as appropriate. The benefits of this method are: ease of access to the ilium, a solid purchase to the ilium, less rod contouring and shorter operating time. We have had no operative complications from this procedure. All patients were discharged home mobile, with a reduced opiate requirement.
Asunto(s)
Fijación Interna de Fracturas/métodos , Fracturas Espontáneas/cirugía , Sacro/lesiones , Adolescente , Adulto , Anciano , Neoplasias Óseas/complicaciones , Tornillos Óseos , Humanos , Persona de Mediana EdadRESUMEN
BACKGROUND: The impact of race and sex on clinical outcomes after percutaneous coronary interventions remains incompletely understood. Specific data on patient demographics, lesion characteristics, and outcomes of black versus white patients are poorly described. To further evaluate these issues, we analyzed the New Approaches in Coronary Interventions (NACI) registry. METHODS: Patients (200 black, 4279 white) undergoing coronary interventions in the NACI trial were compared. A Cox proportional hazards model was used to determine which baseline demographics were independent risk factors for the combined end point of death, Q-wave myocardial infarction, and coronary artery bypass grafting at 1 year. RESULTS: Black patients were significantly younger (age 59 +/- 11 vs 63 +/- 11 years; P <.001), more often obese (29.6 +/- 6 vs 27.5 +/- 4.8 kg/m(2); P <.001), female (50% vs 34%; P <.001), diabetic (34% vs 21%; P <.001), and hypertensive (71% vs 52%; P <.001). Black patients were significantly more likely to have single-vessel disease (48% vs 40%; P <.05) and less likely to have undergone coronary artery bypass grafting (26% vs 34%; P <.05). Blacks were significantly more likely to have a discrete lesion (85% vs 62%; P <. 001) with less thrombus (7% vs 12%; P <.05), tortuosity (17% vs 25%; P <.05), and an ulcerated appearance (5% vs 10%; P <.05). Despite these significant baseline differences, no significant difference was seen in the procedural success (80% vs 82%) or major adverse events (death, Q-wave myocardial infarction, any revascularization) at 1 year (39% vs 34%). Predictors of adverse events for white patients included diabetes (relative risk [RR] = 1.24; confidence intervals [CI], 1.0-1.5) and high-risk status (RR = 1.58; CI, 1.26-1. 91). Predictive characteristics of adverse events for black patients included only sex (RR = 3.45; CI, 1.27-9.35; P =.02). CONCLUSIONS: There are significant differences in baseline characteristics of black patients compared with white patients. Despite these differences in traditional risk factors, they do not affect procedural success or 1-year outcome. In black patients, only sex predicted adverse events. Additional investigation is required to understand the mechanisms for this difference.
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Angioplastia Coronaria con Balón/métodos , Población Negra , Enfermedad Coronaria/etnología , Enfermedad Coronaria/terapia , Población Blanca , Adulto , Distribución por Edad , Anciano , Angioplastia Coronaria con Balón/mortalidad , Intervalos de Confianza , Enfermedad Coronaria/diagnóstico , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Probabilidad , Modelos de Riesgos Proporcionales , Sistema de Registros , Factores de Riesgo , Distribución por Sexo , Tasa de Supervivencia , Resultado del Tratamiento , Estados Unidos/epidemiologíaAsunto(s)
Corazón/diagnóstico por imagen , Función Ventricular Izquierda , Adulto , Anciano , Cardiomiopatías/diagnóstico por imagen , Enfermedad Coronaria/diagnóstico por imagen , Dilatación Patológica , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cintigrafía , Radioisótopos de TalioRESUMEN
The utility of intra-arterial Doppler flow in assessing internal mammary artery (IMA) bypass grafts has infrequently been reported. Two patients are described in which Doppler evaluation of the IMA graft provided valuable diagnostic information prior to intervention. Also provided is a review of the available literature concerning evaluation of pathology in IMA grafts.
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Enfermedad Coronaria/cirugía , Oclusión de Injerto Vascular/diagnóstico , Anastomosis Interna Mamario-Coronaria , Velocidad del Flujo Sanguíneo , Angiografía Coronaria , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Flujo Sanguíneo Regional , UltrasonidoRESUMEN
Metaphyseal chondrodysplasia type Schmid (MCDS) is caused by mutations in COL10A1 that are clustered in the carboxyl-terminal non-collagenous (NC1) encoding domain. This domain is responsible for initiating trimerization of type X collagen during biosynthesis. We have built a molecular model of the NC1 domain trimer based on the crystal structure coordinates of the highly homologous trimeric domain of ACRP30 (adipocyte complement-related protein of 30 kDa or AdipoQ). Mapping of the MCDS mutations onto the structure reveals two specific clusters of residues as follows: one on the surface of the monomer which forms a tunnel through the center of the assembled trimer and the other on a patch exposed to solvent on the exterior surface of each monomeric unit within the assembled trimer. Biochemical studies on recombinant trimeric NC1 domain show that the trimer has an unusually high stability not exhibited by the closely related ACRP30. The high thermal stability of the trimeric NC1 domain, in comparison with ACRP30, appears to be the result of a number of factors including the 17% greater total buried solvent-accessible surface and the increased numbers of hydrophobic contacts formed upon trimerization. The 27 amino acid sequence present at the amino terminus of the NC1 domain, which has no counterpart in ACRP30, also contributes to the stability of the trimer. We have also shown that NC1 domains containing the MCDS mutations Y598D and S600P retain the ability to homotrimerize and heterotrimerize with wild type NC1 domain, although the trimeric complexes formed are less stable than those of the wild type molecule. These studies suggest strongly that the predominant mechanism causing MCDS involves a dominant interference of mutant chains on wild type chain assembly.
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Colágeno/genética , Mutación , Osteocondrodisplasias/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Biopolímeros , Colágeno/metabolismo , Cartilla de ADN , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homología de Secuencia de AminoácidoRESUMEN
Rotational atherectomy is an important technique for the relief of atherosclerotic disease in both coronary and peripheral arteries. Here, we describe an unusual complication, dilutional metabolic acidosis, due to hydration during rotational atherectomy.
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Acidosis/etiología , Aterectomía Coronaria/efectos adversos , Fluidoterapia/efectos adversos , Acidosis/terapia , Estenosis Coronaria/terapia , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Thymidine phosphorylase (EC 2.4.2.4), identical to the angiogenic factor, platelet-derived endothelial cell growth factor (PD-ECGF), is up-regulated in several tumour types. A similarity model of human thymidine phosphorylase was built, based on the crystal structure of the Escherichia coli enzyme. The high residue conservation between the two enzyme sources (39% sequence identity and 53% sequence similarity) aided model building. The human model was very similar to the E. coli enzyme's crystal structure, with the main tertiary structure difference being the destruction of helix 15 in E. coli by the presence of a loop in the human model. The model was used to rationalize the nature of the binding of the substrates thymine and thymidine, and of known inhibitors using a quantitative docking algorithm. Ab initio calculations on the nM inhibitor 5-chloro-6-(1-(2-iminopyrrolidinyl)methyl)uracil hydrochloride gave its conformation and distribution of charge. Subsequent quantitative docking studies have led to the suggestion, for the first time, that this inhibitor behaves as an oxycarbenium ion transition-state analogue, explaining its strong reported inhibition.
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Modelos Moleculares , Neovascularización Patológica , Timidina Fosforilasa/química , Secuencia de Aminoácidos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Humanos , Datos de Secuencia Molecular , Unión Proteica , Homología de Secuencia de Aminoácido , Timidina Fosforilasa/antagonistas & inhibidores , Timidina Fosforilasa/metabolismoRESUMEN
STUDY DESIGN: A prospective clinical study in which autologous rib graft, harvested during the thoracotomy in staged scoliosis correction, is stored within the patient for use during the second stage (posterior intrumentation and fusion). OBJECTIVE: To determine whether the bone stored by this technique is biologically viable and microbiologically safe. SUMMARY OF BACKGROUND DATA: To the authors' knowledge, this method of storage of bone has never been described previously. METHODS: During the first operation, the excised rib was divided into 3-5 cm fragments and stored in a sub-muscular plane adjacent to the posterior elements of the spine before closure. The graft was then retrieved at the second stage. Samples were sent for histologic and microbiologic examination before implantation. RESULTS: On histologic examination, more than 50% of the osteocytes retained their basophilic staining, indicating that they were viable. In addition, osteoclastic activity was notably absent. There was no significant bacterial contamination of the samples. Clinically, all patients achieved satisfactory bone fusion. CONCLUSION: Homeostatic equilibrium in humans provides the ideal environment in which bone graft can be stored. There is no increased risk of infection, and the osteogenic potential of the graft is retained.
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Trasplante Óseo , Costillas/trasplante , Escoliosis/cirugía , Fusión Vertebral/métodos , Supervivencia Celular , Supervivencia de Injerto , Humanos , Preservación de Órganos/métodos , Osteocitos/citología , Estudios Prospectivos , Costillas/microbiología , Costillas/patología , Costillas/cirugía , Trasplante AutólogoRESUMEN
The direct antithrombin, bivalirudin, did not reduce angiographic restenosis measured either as the dichotomous restenosis rate of 62% for bivalirudin and 58% for heparin (p = 0.70), or as the late loss in lumen diameter of 0.44 +/- 0.47 mm for bivalirudin and 0.39 +/- 0.53 mm for heparin (p = 0.62). Direct thrombin inhibition with bivalirudin neither reduces angiographic restenosis nor alters the impact of several established risk factors for restenosis.
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Angioplastia Coronaria con Balón , Antitrombinas/uso terapéutico , Enfermedad Coronaria/prevención & control , Hirudinas/análogos & derivados , Fragmentos de Péptidos/uso terapéutico , Adulto , Anciano , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/terapia , Femenino , Heparina/uso terapéutico , Terapia con Hirudina , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Radiografía , Proteínas Recombinantes/uso terapéutico , Recurrencia , Factores de Riesgo , Resultado del TratamientoRESUMEN
Recently, a new approach has been proposed to improve the site-specificity and efficiency of the modification of nucleic acid target sequences, the binary system of complementary-addressing nucleic acid sequences. The binary system comprises two oligonucleotides, one modified with a photosensitizing group and the other with a photoreactive group. The sites of chemical modification are arranged to bring the two chemical functions close enough together in space to allow efficient energy transfer from the photo-excited photosensitizer to an arylazide moiety which expels N2 to form a nitrene which subsequently covalently labels the target nucleic acid. Structural analysis performed by high-resolution 2D NMR spectroscopy (400 MHz and 600 MHz) are reported for the model binary system 1:2:3, where 1 is the target 12-mer pdGTATCAGTTTCT, 2 is a photoactivatable fluoroazide derivative dAGAAACp-L-Az and 3 is the photosensitizer derivative Pyr-pdTGATAC (here: Az is the p-azidotetrafluorobenzyl group, Pyr the pyrenyl-1-methylamino group, L a linker group). The assignment of oligonucleotide and modifying group protons was performed using 1H COSY, TOCSY and NOESY experiments. Comprehensive analysis of 1H NOESY spectra of 1:2:3 showed that terminal fragments of the complex [5'p-1T-2G-3A-4T-], [-21A-22T-23A-24C], [-8T-9T-10T-11C-12T] and [13A-14G-15A-15A-17A-18C-] gave a continuous set of intra- and inter-nucleotide interactions, typical of regular double-stranded B-DNA. In contrast, the central region of the complex composed of 5C, 6A, 7G, 19T and 20G nucleotide residues, nearest the Pyr and Az groups, was found to be distorted. Thus some signals from aromatic and/or sugar-ring protons of the above nucleotide residues were extremely broadened or almost absent. Moreover, some intra- and/or inter-nucleotide interactions, typical of the regular DNA duplex, were not detected for the [-5C-6A-7G-] and [-19T-20G-] regions of the tandem system. Instead of that, some cross-peaks of low-intensity between the H2 proton of the Pyr group and 7G(H1'), 7G(H2'/H2"), 7G(H3'), 4T(H2"), 4T(H4') and 4T(H5'/H5") were observed. Additional 1H -1H NOE-interactions between methylene protons of the linker group L and some sugar ring protons of 18C nucleotide residue were detected. A preliminary structural model, constructed using proton-proton distances between Pyr and the DNA and Az-L and DNA obtained from a 1H NOESY experiment at 300 ms mixing time as constraints for the refinement of the structure, displayed significant distortion from B-DNA of the double-stranded helix in the middle of the complex, (-5C-6A-7G, -18C-19T-20G-). The Pyr group was located in what remains of the minor groove near 4T, 5C, 6A and 7G and the centroid of the azide ring less than 9A degrees from the centroid of the ring system of Pyr group.
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Benzoatos , ADN Complementario/química , Espectroscopía de Resonancia Magnética/métodos , Modelos Moleculares , Oligodesoxirribonucleótidos/química , Azidas/química , Benzoatos/química , Simulación por Computador , Metilaminas/química , Desnaturalización de Ácido Nucleico , Oligodesoxirribonucleótidos/síntesis química , Fármacos Fotosensibilizantes/química , Pirenos/químicaAsunto(s)
Antibacterianos/química , Antibacterianos/metabolismo , Factor Tu de Elongación Peptídica/química , Factor Tu de Elongación Peptídica/metabolismo , Escherichia coli/metabolismo , Modelos Moleculares , Conformación Molecular , Resonancia Magnética Nuclear Biomolecular , Piridonas/química , Piridonas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Thermus/metabolismoRESUMEN
STUDY DESIGN: Retrospective review of patient records with current clinical and radiographic assessment. OBJECTIVE: To evaluate the long-term result of anterior and posterior convex spinal growth arrest, with or without instrumentation, in managing infantile idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: There were 12 male and 10 female patients studied, with a mean follow-up period of 10 years, 9 months. The mean Cobb angle before surgery was 65 degrees. All had a rib vertebral angle difference more than 20 degrees. The mean age at surgery was 6 years. Nine patients had epiphysiodesis alone; nine patients also underwent Harrington instrumentation simultaneously, and four underwent Harrington instrumentation 2-4 years later. METHOD: Clinical evaluation and sequential measurements of Cobb angle were done. RESULTS: The epiphysiodesis-only group had a mean preoperative Cobb angle of 72 degrees, mean progression of curves of +12 degrees, and mean rate of progression of +2.5 degrees per year: the group's postoperative figures were 92 degrees, +15 degrees, and +3 degrees per year, respectively. The epiphysiodesis and late Harrington rod group had a mean preoperative Cobb angle of 56 degrees, mean progression of +12 degrees, and a mean rate of progression of +5 degrees per year; the group's postoperative Cobb angle averaged 62 degrees, progression +6 degrees, and rate of progression +1 degree per year. The epiphysiodesis with simultaneous Harrington rod group had a preoperative mean Cobb angle of 60 degrees, mean progression of +18 degrees, and mean rate of progression of +6 degrees per years. After surgery, these improved to 58 degrees, correction of 2 degrees, and rate of correction of 0.5 degree per year. CONCLUSION: Combined anterior and posterior convex spinal growth arrest alone does not prevent progression of deformity in infantile idiopathic scoliosis. The addition of posterior instrumentation can slow or arrest deformity progression but not reverse it.
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Escoliosis/prevención & control , Fusión Vertebral/métodos , Columna Vertebral/cirugía , Clavos Ortopédicos , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Estudios Retrospectivos , Escoliosis/cirugía , Resultado del TratamientoRESUMEN
Endothelium-derived relaxing factor is important for vascular homeostasis and possesses qualities that may modulate vascular injury, including vasodilation, platelet inhibition, and inhibition of smooth muscle proliferation. S-nitrososerum albumin is a naturally occurring adduct of nitric oxide (NO) with a prolonged biologic half-life and is a potent vasodilator and platelet inhibitor. Given the avidity of serum albumin for subendothelial matrix and the antiproliferative effects of NO, we investigated the effects of locally delivered S-nitroso-bovine serum albumin (S-NO-BSA) and a polythiolated form of bovine serum albumin (pS-BSA) modified to carry several S-nitrosothiol groups (pS-NO-BSA) on neointimal responses in an animal model of vascular injury. Locally delivered S-NO-BSA bound preferentially to denuded rabbit femoral vessels producing a 26-fold increase in local concentration compared with uninjured vessels (P = 0.029). pS-NO-BSA significantly reduced the intimal/medial ratio (P = 0.038) and did so in conjunction with elevations in platelet (P < 0.001) and vascular cGMP content (P < or = 0.001). pS-NO-BSA treatment also inhibited platelet deposition (P = 0.031) after denuding injury. Comparison of BSA, S-NO-BSA, pS-NO-BSA, and control revealed a dose-response relationship between the amount of displaceable NO delivered and the extent of inhibition of neointimal proliferation at 2 wk (P < or = 0.001). Local administration of a stable protein S-nitrosothiol inhibits intimal proliferation and platelet deposition after vascular arterial balloon injury. This strategy for the local delivery of a long-lived NO adduct has potential for preventing restenosis after angioplasty.
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Plaquetas/fisiología , Arteria Femoral/patología , Músculo Liso Vascular/patología , Óxido Nítrico/farmacología , Albúmina Sérica Bovina/farmacología , Túnica Íntima/patología , 1-Metil-3-Isobutilxantina/farmacología , Animales , Animales Recién Nacidos , Aorta/efectos de los fármacos , Aorta/fisiología , Bovinos , División Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Células Cultivadas , GMP Cíclico/metabolismo , Femenino , Arteria Femoral/efectos de los fármacos , Humanos , Técnicas In Vitro , Radioisótopos de Indio , Masculino , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/fisiología , Compuestos Nitrosos , Adhesividad Plaquetaria/efectos de los fármacos , Conejos , Ratas , Compuestos de Sulfhidrilo/farmacología , Túnica Íntima/citología , Túnica Íntima/efectos de los fármacosRESUMEN
STUDY DESIGN: Retrospective review of patient records with recent clinical and radiologic assessment. OBJECTIVE: To evaluate the long-term result of anterior and posterior convex ephiphysiodesis in the management of congenital scoliosis resulting from fully segmented nonincarcerated hemivertebra. SUMMARY OF BACKGROUND DATA: Thirty patients (16 male/14 female patients) were reviewed. Follow-up was a minimum of 3 years (average, 8 years 10 months; range, 3-22.5 years). Nineteen patients were skeletally mature, and the mean age of the remaining 11 was 11.75 years. METHOD: Clinical evaluation and sequential measurements of Cobb angle was made independently by two observers. RESULTS: Compared with preoperative values, the rate of change in Cobb angle was reversed in 23 patients, arrested or slowed in five patients, and unchanged or progressed in two patients. The annual rate of change in Cobb angle was +1.9 degrees before surgery and -1.2 degrees after surgery, a difference of 3.1 degrees. This is highly statistically significant (P < 0.001). Total correction in Cobb angle correlates with age at time of surgery (P < 0.03). The rate of correction in Cobb angle after surgery correlates with the total correction achieved (P < 0.001) and with age at time of surgery (P < 0.05). The greater correction is achieved when surgery is performed at a young age. The preoperative rate of increase in Cobb angle does not correlate with correction (P < 0.76). The site of the hemivertebrae influenced final outcome with best results in the lumbar spine. CONCLUSION: Combined anterior and posterior convex epiphysiodesis is a reliable method for the correction of deformity resulting from hemivertebrae.
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Epífisis/cirugía , Escoliosis/congénito , Escoliosis/cirugía , Fusión Vertebral , Columna Vertebral/anomalías , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Estudios Longitudinales , Masculino , Estudios Retrospectivos , Escoliosis/etiología , Columna Vertebral/diagnóstico por imagen , Tomografía Computarizada por Rayos XRESUMEN
Four patients with haemangioendothelioma of the spine which was treated surgically are presented. Two were male and two female, mean age 30 years (range 5-60). All tumours were sited in the thoracic spine between T5 and T10; three were primary and one metastatic from a hepatic haemangioendothelioma. Each patient had a significant neurological deficit at presentation; three were paraplegic. A diagnosis of vertebral neoplastic disease was suggested on plain radiographs, and in three cases this was supported by computed tomography or magnetic resonance imaging. Two patients underwent anterior decompression and posterior instrumented stabilisation, one anterior decompression alone and one posterior decompression followed by tumour vessel embolisation and then anterior decompression. Intra-operative blood loss was a significant feature despite the use of hypotensive anaesthetic techniques and local haemostatic agents. Three of the tumours were tested for Factor VIII (a tumour for vascular tumours), and all proved positive. In these, sufficient histological material was available to grade the tumours according to the classification of Campanacci et al. [1]. All were grade II. Three patients recovered completely from paraglegia; one had residual mild spasticity which required the use of a walking aid. The mean improvement in Frankel grade was 2.5 (range 1-4). In two the tumour recurred outside the spine within 18 months; one had subsequently died. The presentation, investigation and results of surgery for haemangioendothelioma of the spine are presented. Particular attention is drawn to the neurological status at presentation, the effect of pre-operative tumour embolisation and the dramatic recovery that can be achieved in these patients following surgery.
Asunto(s)
Hemangioendotelioma/cirugía , Neoplasias de la Columna Vertebral/cirugía , Vértebras Torácicas/cirugía , Adulto , Preescolar , Femenino , Hemangioendotelioma/patología , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Columna Vertebral/patología , Vértebras Torácicas/patologíaRESUMEN
The objective of this study was to evaluate the long term outcome of combined anterior and posterior convex spinal epiphysiodesis in the treatment of congenital scoliosis. The study covered 53 patients (27 male, 26 female) with a minimum follow up period from surgery of 3 years (mean 8.8 years, range 3-22.5 years). Of these, 34 were skeletally mature when reviewed. Clinical assessment and sequential measurement of Cobb angles were used to chart the course of the deformity following surgery. The types of vertebral anomalies encountered were: 4 unsegmented bars, 7 unsegmented bars with hemivertebrae, 30 hemivertebrae (of which 2 were double hemivertebrae) and 12 complex (unclassifiable) patterns. The severe types were concentrated in the thoracic spine. Results are presented with reference to the type and site of anomaly and to the age of the patient at the time of surgery. Where deformity was due to an unsegmented bar (with or without hemivertebra) the rate of change of Cobb angle was slowed, but not reversed, following surgery. For the complex anomalies there was a reduction in the rate of progression of deformity following surgery, however, the final Cobb angle still increased from a mean of 61 degrees to 70 degrees. In contrast, the rate of progression reversed or slowed in 97% of the hemivertebra patients following surgery, producing a change in mean Cobb angle from 41 degrees pre-operatively to 35 degrees post-operatively. For each type of anomaly the correction achieved was greater where the surgery was performed at a younger age. Final outcome was influenced by the site of anomaly, with a better correction being achieved in the lumbar than the thoracic spine. In conclusion, we feel that convex epiphysiodesis has an important role in the surgical management of congenital scoliosis and, for hemivertebrae in particular, it can produce significant correction of deformity.
Asunto(s)
Escoliosis/congénito , Escoliosis/cirugía , Fusión Vertebral , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Escoliosis/diagnóstico , Resultado del TratamientoRESUMEN
O6-Alkylguanine-DNA alkyltransferase (EC 2.1.1.63) repairs O6-alkylguanine lesions in DNA. A homology model of the human protein (hAT) was built, based on the crystal structure of the C-terminal domain of the Ada protein, which carries out a similar repair in Escherichia coli. Sequence alignments of known O6-alkylguanine-DNA alkyltransferases were used to aid the model building using QUANTA and CHARMm software. Despite low homology in the N-terminal half (hAT residues 1-85), a well-defined topology over this region in Ada permitted successful modelling. The C-terminal half of hAT (residues 92-207) was modelled almost entirely by residue-for-residue superposition onto the Ada structure up to residue hAT175. The model was solvated to a residue radius of 8.0 A [corrected] and then minimized using CHARMm. This structural model was used to rationalize findings from site-directed mutagenesis experiments on hAT, to make further predictions on the relationship between structure and function for the alkyltransferase family of proteins, and to explain the specificity towards known small-molecule inhibitors of the protein.