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1.
Am J Sports Med ; 38(8): 1558-63, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20351203

RESUMEN

BACKGROUND: There are no validated outcome measures consistently used in the literature to report results of ulnar collateral ligament reconstruction in overhead athletes. HYPOTHESIS: The Kerlan-Jobe Orthopaedic Clinic Overhead Athlete Shoulder and Elbow score (KJOC score) will correlate with other validated scores for upper extremity assessment but will be more accurate in evaluating ulnar collateral ligament reconstruction outcomes in professional baseball players. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: Fifty-five professional baseball players who underwent ulnar collateral ligament reconstruction were asked to complete the KJOC score, the Disabilities of the Arm, Shoulder and Hand (DASH) score, and the DASH sports module. Players were separated into 3 categories-(1) playing without pain, (2) playing with pain, and (3) not playing because of pain-and compared with 123 asymptomatic throwers. Pearson (parametric) and Spearman rank (nonparametric) correlations among the 3 systems were conducted to validate the KJOC score. Means across categories were compared using a Wilcoxon rank-sum test, and a threshold score separating categories 1 and 3 was determined using receiver operator characteristic discrimination analysis. RESULTS: Significant correlations were found between the KJOC score and the DASH (-.693, P < .0001), and the DASH sports module (-0.804, P < .0001). Only the KJOC score was able to discriminate between categories 2 and 3, as well as category 1 and the uninjured population. In addition, the KJOC score was the most sensitive and accurate method of discriminating category 1 from category 3, with a threshold score of 81.3. CONCLUSION: The results of this study validate the use of the KJOC score for evaluation of overhead athletes undergoing ulnar collateral ligament reconstruction. The KJOC score is the most sensitive score for detecting subtle changes in performance in the throwing athlete.


Asunto(s)
Béisbol/lesiones , Ligamentos Colaterales/cirugía , Procedimientos Ortopédicos/métodos , Índices de Gravedad del Trauma , Cúbito/lesiones , Adulto , Traumatismos en Atletas/fisiopatología , Ligamentos Colaterales/lesiones , Articulación del Codo/fisiopatología , Estudios de Seguimiento , Humanos , Masculino , Articulación del Hombro/fisiopatología , Adulto Joven
2.
Am J Sports Med ; 37(8): 1484-91, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19633301

RESUMEN

BACKGROUND: Increased pitch counts have been linked to increased complaints of shoulder and elbow pain in youth baseball pitchers. Improper pitching mechanics have not been shown to adversely affect the upper extremity in youth pitchers. HYPOTHESIS: The correct performance of 5 biomechanical pitching parameters correlates with lower humeral internal rotation torque and elbow valgus load, as well as higher pitching efficiency, in youth and adolescent pitchers. STUDY DESIGN: Descriptive laboratory study. METHODS: In sum, 169 baseball pitchers (aged 9-18) were analyzed using a quantitative motion analysis system and a high-speed video while throwing fastballs. The correct performance of 5 common pitching parameters was compared with each pitcher's age, humeral internal rotation torque, elbow valgus load, and calculated pitching efficiency. RESULTS: Motion analysis correlated with video analysis for all 5 parameters (P < .05). Youth pitchers (aged 9-13) performing 3 or more parameters correctly showed lower humeral internal rotation torque, lower elbow valgus load, and higher pitching efficiency (P < .05). CONCLUSIONS: Youth pitchers with better pitching mechanics generate lower humeral internal rotation torque, lower elbow valgus load, and more efficiency than do those with improper mechanics. Proper pitching mechanics may help prevent shoulder and elbow injuries in youth pitchers. CLINICAL RELEVANCE: The parameters described in this study may be used to improve the pitching mechanics of youth pitchers and possibly reduce shoulder and elbow pain in youth baseball pitchers.


Asunto(s)
Rendimiento Atlético/normas , Béisbol/fisiología , Fenómenos Biomecánicos/fisiología , Extremidad Superior/fisiología , Adolescente , Traumatismos en Atletas/prevención & control , Niño , Articulación del Codo/fisiología , Humanos , Masculino , Movimiento/fisiología , Lesiones del Hombro , Articulación del Hombro/fisiología , Lesiones de Codo
3.
Ann Surg Oncol ; 15(1): 250-5, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17680314

RESUMEN

BACKGROUND: Sonographic evaluation of the axilla can predict node status in a significant proportion of clinically node-negative patients. This review focuses on the value of ultrasound followed by ultrasound-guided cytology in assessing the need for sentinel node mapping and conservative versus complete axillary dissections. DESIGN: Breast primaries from 168 sentinel node candidates were prospectively assessed for clinicopathologic variables associated with increased incidence of axillary metastases. Patients were classified accordingly, and those at a higher risk underwent ultrasound of their axillae, followed by aspiration biopsy if needed. Sentinel node mapping was performed in all low-risk patients, and in high-risk patients with normal axillary ultrasounds or negative cytology. Final axillary status was compared in terms of nodal stage, number of positive nodes, and size of metastasis. RESULTS: 112 patients were at high risk for nodal disease (67%), with a statistically significant lower probability for remaining node-negative and a statistical significantly higher risk for having more than one positive node. All patients with more than three positive nodes were detected by ultrasound-guided cytology. High-risk patients with final positive axillae missed by ultrasound or ultrasound guided cytology had tumor deposits measuring

Asunto(s)
Biopsia con Aguja Fina/métodos , Neoplasias de la Mama/cirugía , Axila/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Drenaje , Femenino , Humanos , Ganglios Linfáticos , Metástasis Linfática , Estudios Prospectivos , Factores de Riesgo , Biopsia del Ganglio Linfático Centinela , Ultrasonografía
4.
Am J Transplant ; 7(11): 2626-9, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17725682

RESUMEN

Domino heart transplantation has been well described in adults, but has not previously been reported in infant patients. We report the successful transplantation of a 'domino' heart from a 3-month-old infant with primary pulmonary hypertension undergoing heart-lung transplantation, into a 3-month-old infant with complex congenital heart disease. Both infants have survived past 1 year post-transplant, and neither infant has experienced any clinically significant allograft-related complications. Echocardiography and cardiac catheterization of the domino heart have consistently demonstrated stable hypertrophy of the right ventricle (RV) and interventricular septum, but good right and left ventricular function. Domino heart transplant surgery may be an effective way to provide 'pre-conditioned' donor hearts to infants urgently in need of heart transplantation.


Asunto(s)
Trasplante de Corazón/métodos , Trasplante de Corazón-Pulmón , Gasto Cardíaco , Femenino , Trasplante de Corazón-Pulmón/métodos , Humanos , Hipertensión Pulmonar , Lactante , Masculino
5.
Arthroscopy ; 23(7): 723-8, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17637407

RESUMEN

PURPOSE: The purpose of this study was to quantify the distance of dual direct lateral (posterolateral radiocapitellar) arthroscopic portals to the lateral ligamentous structures and to report the percentage of capitellum accessible through these portals. METHODS: Arthroscopy was performed on 10 fresh-frozen cadaveric elbows via a standard 6-portal approach. The portals included dual direct lateral portals created in the posterolateral soft spot. The arthroscope was placed through one direct lateral portal; an arthroscopic electrocautery device was placed through the other direct lateral portal and was used to mark all accessible areas of the capitellum. Open dissection allowed measurement of the distances of the portals from the lateral ligamentous structures, as well as determination of the percentage of capitellum accessible through these portals. RESULTS: The more ulnar of the dual lateral portals averaged 9.1 mm from the lateral ulnar collateral ligament, 11.5 mm from the annular ligament, and 13.1 mm from the radial collateral ligament. The more radial of the dual lateral portals averaged 1.5 mm, 9.7 mm, and 7.0 mm from these ligaments, respectively. Seventy-eight percent of the capitellum was accessible for instrumentation with these portals. CONCLUSIONS: Correct placement of dual direct lateral portals does not disrupt the lateral ligamentous complex and allows access to a large portion of the capitellum. CLINICAL RELEVANCE: Use of dual direct lateral portals is safe and practical for arthroscopic treatment of capitellar osteochondritis dissecans.


Asunto(s)
Artroscopía/métodos , Articulación del Codo/cirugía , Osteocondritis Disecante/cirugía , Anciano , Cadáver , Articulación del Codo/fisiopatología , Electrocoagulación/instrumentación , Femenino , Humanos , Masculino , Postura , Rango del Movimiento Articular , Resultado del Tratamiento
6.
Ann Thorac Surg ; 72(3): 872-7; discussion 878, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11565673

RESUMEN

BACKGROUND: In 1995, we reported the use of lateral thoracic expansion in a patient with symptomatic Jeune's asphyxiating thoracic dystrophy. We have subsequently used lateral thoracic expansion 16 times on 10 patients during 7 years. This article reports our outcomes and provides surgical details. METHODS: Charts of all patients undergoing lateral thoracic expansion were reviewed. Eight of the 10 patients had symptomatic Jeune's syndrome. The other 2 had similar thoracic deformities limiting thoracic capacity. In half of the patients the procedures were performed bilaterally. RESULTS: All patients older than 1 year of age were symptomatically benefited by lateral thoracic expansion. Functional and anatomic measurements documented thoracic enlargement in several patients who had comparable preoperative and postoperative studies. However, 2 infants with significant underlying airway disease did not improve and went on to succumb to that aspect of their disease despite enlargement of the thorax. Fracture of the titanium ministruts has been a recurrent problem, and we now use larger struts. CONCLUSIONS: Lateral thoracic expansion is a safe and effective procedure in selected patients with Jeune's syndrome older than 1 year of age as judged by short-term and midterm follow-up. More experience and longer follow-up are required to discern the place of the lateral thoracic expansion in the overall management of these patients.


Asunto(s)
Alargamiento Óseo/métodos , Osteocondrodisplasias/cirugía , Insuficiencia Respiratoria/etiología , Costillas/anomalías , Costillas/cirugía , Procedimientos Quirúrgicos Torácicos/métodos , Adolescente , Placas Óseas , Niño , Preescolar , Femenino , Humanos , Mediciones del Volumen Pulmonar , Masculino , Osteocondrodisplasias/complicaciones , Osteocondrodisplasias/diagnóstico por imagen , Osteocondrodisplasias/patología , Radiografía Torácica , Síndrome , Tomografía Computarizada por Rayos X
7.
Int J Psychoanal ; 82(Pt 3): 449-62, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11436246

RESUMEN

The author reviews a contemporary cognitive psychology perspective on memory that views memory as being composed of multiple separate systems. Most researchers draw a fundamental distinction between declarative/explicit and non-declarative/implicit forms of memory. Declarative memory is responsible for the conscious recollection of facts and events--what is typically meant by the everyday and the common psychoanalytic use of the word 'memory'. Non-declarative forms of memory, in contrast, are specialised processes that influence experience and behaviour without representing the past in terms of any consciously accessible content. They operate outside of an individual's awareness, but are not repressed or otherwise dynamically unconscious. Using this theoretical framework, the question of how childhood relationship experiences are carried forward from the past to influence the present is examined. It is argued that incorporating a conceptualisation of non-declarative memory processing into psychoanalytic theory is essential. Non-declarative memory processes are capable of forming complex and sophisticated representations of the interpersonal world. These non-declarative memory processes exert a major impact on interpersonal experience and behaviour that needs to be analysed on its own terms and not mistakenly viewed as a form of resistance.


Asunto(s)
Memoria/fisiología , Interpretación Psicoanalítica , Teoría Psicoanalítica , Terapia Psicoanalítica/tendencias , Afecto , Estado de Conciencia/fisiología , Humanos
9.
J Ultrasound Med ; 20(3): 207-15, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11270524

RESUMEN

Recently the North American Symptomatic Carotid Endarterectomy Trial investigators reported a benefit of carotid endarterectomy compared with medical therapy for symptomatic patients with 50% or greater carotid stenosis. This has necessitated the development of screening parameters for diagnosis of 50% or greater carotid stenosis on the basis of the reference standards used in the study by the North American Symptomatic Carotid Endarterectomy Trial. The duplex scans and arteriograms of 110 patients (210 carotid arteries) were reviewed by blinded readers. Duplex measurements of peak systolic velocity and end diastolic velocity were recorded, and the ratio of these velocities in the internal and common carotid arteries was calculated. The criteria determined for detection of 50% or greater stenosis were as follows: peak systolic velocity of the internal carotid artery greater than 170 cm/s (sensitivity, 92%; specificity, 90%; positive predictive value, 92%; negative predictive value, 90%; and accuracy, 91 %); end diastolic velocity of the internal carotid artery greater than 60 cm/s (sensitivity, 92%; specificity, 86%; positive predictive value, 95%; negative predictive value, 79%; and accuracy, 91 %); ratio of peak systolic velocity of the internal carotid artery to peak systolic velocity of the common carotid artery greater than 2 (sensitivity, 93%; specificity, 75%; positive predictive value, 83%; negative predictive value, 89%; and accuracy, 85%); and ratio of end diastolic velocity of the internal carotid artery to end diastolic velocity of the common carotid artery greater than 2.4 (sensitivity, 96%; specificity, 79%; positive predictive value, 88%; negative predictive value, 92%; and accuracy, 89%). It is concluded that 50% or greater carotid artery stenosis can be reliably determined by duplex criteria. The use of receiver operating characteristic curves allows the individualization of duplex criteria to the clinical situation.


Asunto(s)
Estenosis Carotídea/diagnóstico por imagen , Ultrasonografía Doppler Dúplex , Velocidad del Flujo Sanguíneo , Estenosis Carotídea/cirugía , Endarterectomía Carotidea , Humanos , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Curva ROC , Sensibilidad y Especificidad
10.
Chemistry ; 7(2): 388-95, 2001 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-11271525

RESUMEN

Lipophilic guanosine derivatives act as self-assembled ionophores. In the presence of alkali metal ions in organic solvents, these G derivatives can form tubular polymeric structures. The molecular aggregates formed by 3',5'-didecanoyl-2'-deoxyguanosine (1) have been characterised by SANS and NMR spectroscopy. The polymer is structured as a pile of stacked G quartets held together by the alkali metal ions that occupy the column's central channel. The deoxyribose moieties, with their alkyl substituents, surround the stacked G quartets, and the nucleoside's long-chain alkyl tails are in intimate contact with the organic solvent. In this polymeric structure, there is an amazing regularity in the rotamers around the glycosidic bond within each G quartet and in the repeat sequence of the G quartets along the columns. In hydrocarbon solvents, these columnar aggregates form lyomesophases of the cholesteric and hexagonal types.


Asunto(s)
Guanosina/química , Conformación de Ácido Nucleico , Biopolímeros/química , Espectroscopía de Resonancia Magnética
11.
Pediatr Pulmonol ; 31(1): 80-5, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11180679

RESUMEN

SUMMARY. We utilized improved methods for assessing airway structure and function to define the clinical significance of the innominate artery syndrome. Both infant pulmonary function tests (IPFT) and noninvasive controlled ventilation computed tomography (CVCT) were used, along with traditional diagnostic techniques in a 2-month-old child with compression of the trachea by the innominate artery. These tests provided objective documentation of functional impairment before surgery and improvement postoperatively. These tests should aid in the understanding of this controversial syndrome and help to further define treatment options.


Asunto(s)
Obstrucción de las Vías Aéreas/etiología , Tronco Braquiocefálico/anomalías , Enfermedades de la Tráquea/etiología , Aorta/cirugía , Tronco Braquiocefálico/cirugía , Broncoscopía , Estudios de Seguimiento , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Respiración , Pruebas de Función Respiratoria , Ruidos Respiratorios/etiología , Síndrome , Tomografía Computarizada por Rayos X
12.
Bull Menninger Clin ; 65(4): 451-70, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11761491

RESUMEN

Cognitive psychology research challenges traditional psychoanalytic understanding of memory. The memory of facts and events is now referred to as declarative memory. Nondeclarative memory systems, in contrast, process patterns of perception, emotion, and action without representing the past in terms of any consciously accessible content. The author examines the contributions of declarative and nondeclarative memory processes to resilience. Declarative memories can promote resilience through their capacity to evoke soothing emotional responses. Nondeclarative memory processes can foster resilience through underlying the capacity to elicit and maintain supportive relationships. The concept of nondeclarative memory has potential to inform the understanding of essential psychoanalytic phenomena, including transference, countertransference, and enactment.


Asunto(s)
Memoria/fisiología , Afecto , Anciano , Condicionamiento Clásico , Hábitos , Humanos , Relaciones Interpersonales , Masculino , Teoría Psicológica , Desempeño Psicomotor
13.
Org Lett ; 2(12): 1665-8, 2000 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-10880196

RESUMEN

[reaction: see text] Self-assembled ionophores, formed by hydrogen bonding of isoG 1 around a cation, are dynamic structures. Multinuclear NMR spectroscopy in CD(3)CN-CDCl(3) showed that cation exchange is >10(4) faster than exchange of isoG 1 ligand in (isoG 1)(10)-Cs(+) Ph(4)B(-). The cationic guest also affected the kinetic stability of the complex. 2D-EXSY NMR experiments in CDCl(3) showed that ligand exchange was 2 orders of magnitude faster for the Li(+)-decamer than for the Cs(+)-decamer.


Asunto(s)
Ionóforos/química , Cationes/metabolismo , Guanosina/análogos & derivados , Guanosina/química , Guanosina/metabolismo , Enlace de Hidrógeno , Transporte Iónico , Ionóforos/metabolismo , Cinética , Ligandos , Espectroscopía de Resonancia Magnética , Conformación Molecular , Estructura Molecular
14.
J Clin Neurophysiol ; 17(2): 224-31, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10831113

RESUMEN

Sleep spindles in EEG recordings of adults are most prominent over the central and frontal midline regions. Early magnetoencephalographic recordings agreed with conventional EEG findings. However, more recent small-array magnetoencephalography and quantitative EEG studies suggest that the source areas for spindles are more widespread. We used a whole-head 122-channel biomagnetometer to characterize the sources of sleep spindles in four normal volunteers. Parallel interactive and automated multiple dipole spatiotemporal source modeling was conducted on the data sets of 10 spindles from each subject. Principal component analysis was used to estimate the number of sources in interactive source modeling, and singular value decomposition was used in automated dipole modeling. Spectral analysis of the epochs containing sleep spindles was performed. Principal component analysis and singular value decomposition suggested that all sleep spindles were made up of activity from multiple sources. Similarly, interactive and automated multiple dipole source modeling showed that three or more sources were present in 75% of spindle bursts. The sources for sleep spindles localized to all four cerebral lobes. Parietal and frontal lobes were the areas most frequently involved. Interactive source modeling resulted in more frequent temporal lobe than occipital dipole localizations; automated source modeling showed more frequent occipital than temporal sources. Spindle source localizations varied across subjects and across different spindles within subjects. Our results indicate that individual sleep spindles are generated by multiple cortical sources that are widespread within and across individuals.


Asunto(s)
Encéfalo/fisiología , Magnetoencefalografía/métodos , Sueño/fisiología , Adolescente , Adulto , Niño , Electroencefalografía , Femenino , Lóbulo Frontal/fisiología , Humanos , Masculino , Lóbulo Parietal/fisiología , Lóbulo Temporal/fisiología
15.
Am J Orthopsychiatry ; 70(2): 215-22, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10826033

RESUMEN

Seventy-three inner-city boys with a mean IQ of 80 were followed prospectively from age 14 until age 65. Their adult adjustment was compared to a socioeconomically matched sample of 38 boys with a mean IQ of 115. Although childhood social disadvantage did not distinguish the groups with low and high IQs, half of the low-IQ men enjoyed incomes as high and had children as well-educated as did the high IQ men. These resilient low-IQ men were more likely to be generative, to use mature defenses, and to enjoy warm object relations than the high IQ group as a whole.


Asunto(s)
Discapacidad Intelectual/psicología , Inteligencia , Desarrollo de la Personalidad , Ajuste Social , Población Urbana , Adaptación Psicológica , Adolescente , Adulto , Anciano , Boston , Niño , Creatividad , Mecanismos de Defensa , Humanos , Masculino , Persona de Mediana Edad , Apego a Objetos , Estudios Prospectivos
16.
Cardiol Young ; 10(1): 27-31, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10695537

RESUMEN

Intrapericardial teratomas are rare primary cardiac tumors of infancy and childhood. We describe three neonates with intrapericardial teratomas diagnosed during fetal life and treated after birth. Clinical and anatomic considerations suggest that cardiopulmonary bypass provides for safe tumor dissection and complete excision of the tumor, thereby decreasing the risk of recurrence.


Asunto(s)
Neoplasias Cardíacas/cirugía , Teratoma/cirugía , Puente Cardiopulmonar , Resultado Fatal , Femenino , Neoplasias Cardíacas/diagnóstico por imagen , Neoplasias Cardíacas/patología , Humanos , Recién Nacido , Pericardio , Embarazo , Teratoma/diagnóstico por imagen , Teratoma/patología , Ultrasonografía Prenatal
17.
J Neurosurg ; 92(1): 79-90, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10616086

RESUMEN

OBJECT: The availability of large-array biomagnetometers has led to advances in magnetoencephalography that permit scientists and clinicians to map selected brain functions onto magnetic resonance images. This merging of technologies is termed magnetic source (MS) imaging. The present study was undertaken to assess the role of MS imaging for the guidance of presurgical planning and intraoperative neurosurgical technique used in patients with intracranial mass lesions. METHODS: Twenty-six patients with intracranial mass lesions underwent a medical evaluation consisting of MS imaging, a clinical history, a neurological examination, and assessment with the Karnofsky Performance Scale. Magnetic source imaging was used to locate the somatosensory cortex in 25 patients, the visual cortex in six, and the auditory cortex in four. The distance between the lesion and the functional cortex was determined for each patient. Twenty-one patients underwent a neurosurgical procedure. As a surgical adjunct, a frameless stereotactic navigational system was used in 17 cases and a standard stereotactic apparatus in four cases. Because of the results of their MS imaging examination, two patients were not offered surgery, four underwent a stereotactic biopsy procedure, 10 were treated with a subtotal surgical resection, and seven were treated with complete surgical resection. One patient deteriorated before a procedure could be scheduled and, therefore, was not offered surgery, and two patients were offered surgery but declined. Three patients experienced surgery-related complications. CONCLUSIONS: Magnetic source imaging is an important noninvasive neurodiagnostic tool that provides critical information regarding the spatial relationship of a brain lesion to functional cortex. By providing this information, MS imaging facilitates a minimum-risk management strategy and helps guide operative neurosurgical technique in patients with intracranial mass lesions.


Asunto(s)
Neoplasias Encefálicas/fisiopatología , Neoplasias Encefálicas/cirugía , Encéfalo/fisiopatología , Encéfalo/cirugía , Imagen por Resonancia Magnética , Magnetoencefalografía , Procedimientos Neuroquirúrgicos/métodos , Adulto , Anciano , Encéfalo/patología , Neoplasias Encefálicas/patología , Niño , Toma de Decisiones , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Magnetoencefalografía/métodos , Masculino , Persona de Mediana Edad , Planificación de Atención al Paciente , Técnicas Estereotáxicas , Resultado del Tratamiento
18.
J Extra Corpor Technol ; 32(3): 138-41, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11146957

RESUMEN

There is a great effort to decrease blood product use during open-heart surgery in pediatrics. We were presented with a research challenge to accomplish heart xenotransplantation from donor cynomologous monkey (Macaca fascicularis) to recipient olive baboon (Papio anubis) of 5-7 kilograms without benefit of donor or banked blood products. The purpose of this study was to design and implement a practical, low-volume circuit to minimize hemodilution and avoid the use of blood products. A simple circuit was assembled using a low-volume oxygenator with hardshell venous reservoir, an 1/8-inch arterial line, an 1/4-inch venous line, and gravity drainage. Three xenotransplants were performed and evaluated. The mean recipient weights were 6.3 +/- 0.7 kg. Circuit prime volume was 228 +/- 5.8 mL, and bypass time was 85 +/- 6.7 min. Blood flow rates were 585 +/- 113 mL/min with postmembrane arterial line pressures of 344 +/- 81 mmHg, and patient mean arterial pressures (MAP) of 51.4 +/- 16.7 mmHg. Venous saturations were 63.7 +/- 8.0%. The hematocrit prebypass was 37.4 +/- 3.2, bypass 20.7 +/- 0.9, post-MUF 27.8 +/- 3.3, and 7 days postoperative 24.5 +/- 7.5%. Platelet count was 289 +/- 1.1 K/microL, 147 +/- 37.1 K/microL, and 322 +/- 292.7 K/microL prebypass, postbypass, and 7 days postoperative, respectively. Plasma-free hemoglobin prebypass was 7.5 +/- 4.4 mg/dL and postbypass 22.2 +/- 16.5 mg/dL with no noted hematuria during and after the procedure. All patients survived and were successfully weaned from cardiopulmonary bypass (CPB) with same day extubation. A low-prime circuit for bloodless heart surgery is possible. To achieve low reservoir levels, especially without the use of an arterial line filter (ALF), it is necessary to have a full armament of monitoring and alarm devices.


Asunto(s)
Pérdida de Sangre Quirúrgica/prevención & control , Trasplante de Corazón/instrumentación , Trasplante Heterólogo/métodos , Animales , Peso Corporal , Trasplante de Corazón/métodos , Hematócrito/estadística & datos numéricos , Macaca fascicularis , Papio , Estados Unidos
19.
Pediatrics ; 104(3 Pt 1): 405-18, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10469763

RESUMEN

BACKGROUND: One-third of children diagnosed with autism spectrum disorders (ASDs) are reported to have had normal early development followed by an autistic regression between the ages of 2 and 3 years. This clinical profile partly parallels that seen in Landau-Kleffner syndrome (LKS), an acquired language disorder (aphasia) believed to be caused by epileptiform activity. Given the additional observation that one-third of autistic children experience one or more seizures by adolescence, epileptiform activity may play a causal role in some cases of autism. OBJECTIVE: To compare and contrast patterns of epileptiform activity in children with autistic regressions versus classic LKS to determine if there is neurobiological overlap between these conditions. It was hypothesized that many children with regressive ASDs would show epileptiform activity in a multifocal pattern that includes the same brain regions implicated in LKS. DESIGN: Magnetoencephalography (MEG), a noninvasive method for identifying zones of abnormal brain electrophysiology, was used to evaluate patterns of epileptiform activity during stage III sleep in 6 children with classic LKS and 50 children with regressive ASDs with onset between 20 and 36 months of age (16 with autism and 34 with pervasive developmental disorder-not otherwise specified). Whereas 5 of the 6 children with LKS had been previously diagnosed with complex-partial seizures, a clinical seizure disorder had been diagnosed for only 15 of the 50 ASD children. However, all the children in this study had been reported to occasionally demonstrate unusual behaviors (eg, rapid blinking, holding of the hands to the ears, unprovoked crying episodes, and/or brief staring spells) which, if exhibited by a normal child, might be interpreted as indicative of a subclinical epileptiform condition. MEG data were compared with simultaneously recorded electroencephalography (EEG) data, and with data from previous 1-hour and/or 24-hour clinical EEG, when available. Multiple-dipole, spatiotemporal modeling was used to identify sites of origin and propagation for epileptiform transients. RESULTS: The MEG of all children with LKS showed primary or secondary epileptiform involvement of the left intra/perisylvian region, with all but 1 child showing additional involvement of the right sylvian region. In all cases of LKS, independent epileptiform activity beyond the sylvian region was absent, although propagation of activity to frontal or parietal regions was seen occasionally. MEG identified epileptiform activity in 41 of the 50 (82%) children with ASDs. In contrast, simultaneous EEG revealed epileptiform activity in only 68%. When epileptiform activity was present in the ASDs, the same intra/perisylvian regions seen to be epileptiform in LKS were active in 85% of the cases. Whereas primary activity outside of the sylvian regions was not seen for any of the children with LKS, 75% of the ASD children with epileptiform activity demonstrated additional nonsylvian zones of independent epileptiform activity. Despite the multifocal nature of the epileptiform activity in the ASDs, neurosurgical intervention aimed at control has lead to a reduction of autistic features and improvement in language skills in 12 of 18 cases. CONCLUSIONS: This study demonstrates that there is a subset of children with ASDs who demonstrate clinically relevant epileptiform activity during slow-wave sleep, and that this activity may be present even in the absence of a clinical seizure disorder. MEG showed significantly greater sensitivity to this epileptiform activity than simultaneous EEG, 1-hour clinical EEG, and 24-hour clinical EEG. The multifocal epileptiform pattern identified by MEG in the ASDs typically includes the same perisylvian brain regions identified as abnormal in LKS. When epileptiform activity is present in the ASDs, therapeutic strategies (antiepileptic drugs, steroids, and even neurosurgery) aimed at its control can lead to a significa


Asunto(s)
Trastorno Autístico/diagnóstico , Encéfalo/fisiopatología , Epilepsia/diagnóstico , Síndrome de Landau-Kleffner/diagnóstico , Magnetoencefalografía , Trastorno Autístico/fisiopatología , Niño , Trastornos Generalizados del Desarrollo Infantil/diagnóstico , Trastornos Generalizados del Desarrollo Infantil/fisiopatología , Preescolar , Electroencefalografía , Epilepsia/fisiopatología , Femenino , Humanos , Síndrome de Landau-Kleffner/fisiopatología , Masculino , Sueño/fisiología
20.
AJNR Am J Neuroradiol ; 20(5): 857-66, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10369357

RESUMEN

BACKGROUND AND PURPOSE: Patients with mild traumatic brain injury (TBI) often show significant neuropsychological dysfunction despite the absence of abnormalities on traditional neuroradiologic examinations or EEG. Our objective was to determine if magnetic source imaging (MSI), using a combination of MR imaging and magnetoencephalography (MEG), is more sensitive than EEG and MR imaging in providing objective evidence of minor brain injury. METHODS: Four subject groups were evaluated with MR, MSI, and EEG. Group A consisted of 20 neurologically normal control subjects without histories of head trauma. Group B consisted of 10 subjects with histories of mild head trauma but complete recovery. Group C consisted of 20 subjects with histories of mild head injury and persistent postconcussive symptoms. The 15 subjects included in group D underwent repeat examinations at an interval of 2 to 4 months. RESULTS: No MR abnormalities were seen in the normal control group or the asymptomatic group, but five (20%) of the patients with persistent postconcussive symptoms had abnormal MR findings. EEG was abnormal for one subject (5%) from the normal control group, one (10%) from the asymptomatic group, and five (20%) from the group with persistent postconcussive symptoms. MSI was abnormal for one subject (5%) from the normal control group, one (10%) from the asymptomatic group, and 13 (65%) from the group with persistent postconcussive symptoms. There was a direct correlation between symptom resolution and MSI findings for the symptomatic head trauma group. CONCLUSION: MSI indicated brain dysfunction in significantly more patients with postconcussive symptoms than either EEG or MR imaging (P < .01). The presence of excessive abnormal low-frequency magnetic activity provides objective evidence of brain injury in patients with postconcussive syndromes and correlates well with the degree of symptomatic recovery.


Asunto(s)
Lesiones Encefálicas/diagnóstico , Imagen por Resonancia Magnética , Magnetoencefalografía , Adolescente , Adulto , Encéfalo/patología , Lesiones Encefálicas/fisiopatología , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad
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