Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 113
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Emerg Med ; 52(4): 559-561, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28094079

RESUMEN

BACKGROUND: Acute lymphoblastic leukemia (ALL) is the most common form of childhood leukemia. The treatment of ALL involves multimodality therapy, and methotrexate (MTX) remains a mainstay of treatment. A complication of MTX therapy includes acute, subacute, and chronic neurotoxocity. Signs and symptoms may range from headaches, dizziness, and mood disorders to seizures and stroke-like symptoms. CASE REPORT: An 18-year-old woman with a history of ALL presented to the emergency department with acute onset of right-sided facial paralysis, right upper extremity flaccid paralysis, and right lower extremity weakness after receiving MTX therapy 3 days earlier. Diagnostic studies were unremarkable and the patient was treated with oral dextromethorphan for presumed MTX-induced neurotoxicity. The patient's symptoms began to improve within hours and she was discharged home within 48 hours with no neurologic deficits. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians should be aware of this complication of MTX therapy given the sensitivity in regards to time with respect to cerebral vascular accidents. An awareness of this complication in the setting of the appropriate history and physical examination can lead to an accurate diagnosis and intervention and the avoidance of administering thrombolytics.


Asunto(s)
Metotrexato/toxicidad , Síndromes de Neurotoxicidad/etiología , Accidente Cerebrovascular/diagnóstico , Adolescente , Antimetabolitos Antineoplásicos/farmacología , Antimetabolitos Antineoplásicos/uso terapéutico , Terapia Combinada/métodos , Dextrometorfano/farmacología , Dextrometorfano/uso terapéutico , Servicio de Urgencia en Hospital/organización & administración , Antagonistas de Aminoácidos Excitadores/farmacología , Antagonistas de Aminoácidos Excitadores/uso terapéutico , Parálisis Facial/etiología , Femenino , Humanos , Extremidad Inferior/inervación , Extremidad Inferior/fisiopatología , Metotrexato/farmacología , Metotrexato/uso terapéutico , Hipotonía Muscular/etiología , Debilidad Muscular/etiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Extremidad Superior/inervación , Extremidad Superior/fisiopatología
3.
J Sports Sci ; 33(19): 2061-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25846204

RESUMEN

The match-play demands of rugby union have increased over time, and these demands should be quantified so as to provide a basis for optimal player loading during training. The primary aim of this article was to quantify accelerations, decelerations, impacts and aggregated body demands during the first half of match-play in a Super Rugby team. The secondary aim was to determine whether these characteristics are position-specific. Thirty-three players were monitored for 14 matches using global positioning system units with inbuilt microtechnology. Players were grouped according to positional roles and data were analysed for those who completed the entire duration of the first half of a given match. Forwards sustained more (d = 0.44) high-intensity impacts and greater (d = 0.26) aggregated body demands, while backs had more moderate (d = 0.55) and heavy accelerations (d = 0.76), and moderate (d = 0.23) and heavy decelerations (d = 0.54). These differences suggest that conditioning and recovery strategies should reflect the physical demands placed on players in different playing positions. Forwards should be conditioned with a focus on impacts and require longer recovery for the same duration of playing time, whereas conditioning for backs should emphasise rapid accelerations and decelerations.


Asunto(s)
Rendimiento Atlético/fisiología , Conducta Competitiva/fisiología , Fútbol/fisiología , Aceleración , Adulto , Sistemas de Información Geográfica , Humanos , Masculino , Destreza Motora/fisiología , Educación y Entrenamiento Físico , Estaciones del Año , Estudios de Tiempo y Movimiento , Adulto Joven
4.
Pediatr Blood Cancer ; 61(4): 636-42, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24123865

RESUMEN

BACKGROUND: Preclinical models show that an antiangiogenic regimen at low-dose daily (metronomic) dosing may be effective against chemotherapy-resistant tumors. We undertook a prospective, open-label, single-arm, multi-institutional phase II study to evaluate the efficacy of a "5-drug" oral regimen in children with recurrent or progressive cancer. PROCEDURE: Patients ≤21 years old with recurrent or progressive tumors were eligible. Treatment consisted of continuous oral celecoxib, thalidomide, and fenofibrate, with alternating 21-day cycles of low-dose cyclophosphamide and etoposide. Primary endpoint was to assess, within eight disease strata, activity of the 5-drug regimen over 27 weeks. Blood and urine angiogenesis markers were assessed. RESULTS: One hundred one patients were enrolled; 97 began treatment. Median age was 10 years (range: 191 days-21 years); 47 (49%) were female. Disease strata included high-grade glioma (HGG, 21 patients), ependymoma (19), low-grade glioma (LGG, 12), bone tumors (12), medulloblastoma/primitive neuroectodermal tumor (PNET, 8), leukemia (4), neuroblastoma (3), and miscellaneous tumors (18). Treatment was generally well tolerated; most common toxicities were hematologic. Twenty-four (25%) patients completed 27 weeks therapy without progression, including HGG: 1 (5%), ependymoma: 7 (37%), LGG: 7 (58%), medulloblastoma/PNET: 1, neuroblastoma: 1, and miscellaneous tumors: 7 (39%). Best response was complete response (one patient with medulloblastoma), partial response (12), stable disease (36), progressive disease (47), and inevaluable (1). Baseline serum thrombospondin levels were significantly higher in patients successfully completing therapy than in those who progressed (P = 0.009). CONCLUSION: The 5-drug regimen was well tolerated. Clinical activity was demonstrated in some but not all tumor strata.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Adolescente , Adulto , Celecoxib , Niño , Preescolar , Ciclofosfamida/administración & dosificación , Etopósido/administración & dosificación , Femenino , Fenofibrato/administración & dosificación , Estudios de Seguimiento , Humanos , Lactante , Masculino , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Neoplasias/patología , Pronóstico , Estudios Prospectivos , Pirazoles/administración & dosificación , Sulfonamidas/administración & dosificación , Tasa de Supervivencia , Talidomida/administración & dosificación , Adulto Joven
5.
Mol Microbiol ; 84(3): 516-29, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22435733

RESUMEN

Burkholderia pseudomallei is a category B pathogen and the causative agent of melioidosis--a serious infectious disease that is typically acquired directly from environmental reservoirs. Nearly all B. pseudomallei strains sequenced to date (> 85 isolates) contain gene clusters that are related to the contact-dependent growth inhibition (CDI) systems of γ-proteobacteria. CDI systems from Escherichia coli and Dickeya dadantii play significant roles in bacterial competition, suggesting these systems may also contribute to the competitive fitness of B. pseudomallei. Here, we identify 10 distinct CDI systems in B. pseudomallei based on polymorphisms within the cdiA-CT/cdiI coding regions, which are predicted to encode CdiA-CT/CdiI toxin/immunity protein pairs. Biochemical analysis of three B. pseudomallei CdiA-CTs revealed that each protein possesses a distinct tRNase activity capable of inhibiting cell growth. These toxin activities are blocked by cognate CdiI immunity proteins, which specifically bind the CdiA-CT and protect cells from growth inhibition. Using Burkholderia thailandensis E264 as a model, we show that a CDI system from B. pseudomallei 1026b mediates CDI and is capable of delivering CdiA-CT toxins derived from other B. pseudomallei strains. These results demonstrate that Burkholderia species contain functional CDI systems, which may confer a competitive advantage to these bacteria.


Asunto(s)
Proteínas Bacterianas/inmunología , Toxinas Bacterianas/inmunología , Burkholderia pseudomallei/crecimiento & desarrollo , Burkholderia pseudomallei/metabolismo , Inhibición de Contacto , Melioidosis/inmunología , Melioidosis/microbiología , Proteínas Bacterianas/genética , Toxinas Bacterianas/genética , Burkholderia pseudomallei/enzimología , Burkholderia pseudomallei/genética , Endorribonucleasas/genética , Endorribonucleasas/metabolismo , Humanos , Familia de Multigenes
6.
Science ; 269(5224): 664-6, 1995 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-7624795

RESUMEN

Microcontact printing (mu CP) has been used to produce patterned self-assembled monolayers (SAMs) with submicrometer features on curved substrates with radii of curvature as small as 25 micrometers. Wet-chemical etching that uses the patterned SAMs as resists transfers the patterns formed by mu CP into gold. At present, there is no comparable method for microfabrication on curved surfaces.


Asunto(s)
Química Física/métodos , Dimetilpolisiloxanos/química , Oro/química , Siliconas/química , Propiedades de Superficie
7.
Science ; 269(5228): 1255-7, 1995 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-7652572

RESUMEN

Lithography can be performed with beams of neutral atoms in metastable excited states to pattern self-assembled monolayers (SAMs) of alkanethiolates on gold. An estimated exposure of a SAM of dodecanethiolate (DDT) to 15 to 20 metastable argon atoms per DDT molecule damaged the SAM sufficiently to allow penetration of an aqueous solution of ferricyanide to the surface of the gold. This solution etched the gold and transformed the patterns in the SAMs into structures of gold; these structures had edge resolution of less than 100 nanometers. Regions of SAMs as large as 2 square centimeters were patterned by exposure to a beam of metastable argon atoms. These observations suggest that this system may be useful in new forms of micro- and nanolithography.


Asunto(s)
Química Física , Oro , Compuestos de Sulfhidrilo , Propiedades de Superficie , Argón , Fenómenos Químicos , Ferricianuros , Microscopía Electrónica/instrumentación
9.
Undersea Hyperb Med ; 36(2): 127-36, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19462752

RESUMEN

Indirect evidence suggests that microbubbles that exist normally in tissue may play a key role in decompression sickness (DCS). Their sizes and locations are unknown. Dual-frequency ultrasound (DFU) exploits bubble resonance to detect bubbles over a wide size range and could potentially detect stationary tissue microbubbles. To test this capability, DFU was used to detect stationary microbubbles of known size (2-3 microm mean diameter) over a range of ultrasound pressures and microbubble concentrations. In gelatin phantoms doped with microbubbles and in ex vivo porcine tissue, signals indicative of bubbles were detected for microbubble concentrations of 5x10(5) per mL and greater. Signals were not returned from solid particle microspheres of similar size to the microbubbles or from saline controls. In the thigh of an anesthetized swine, signals were detected for concentrations of 5x10(7) per mL and greater. Because of its ability to detect bubbles over a wide range of sizes, this technique could potentially detect naturally-existing microbubbles in tissue and lead to (a) an improved understanding of the mechanics of bubble formation during decompression and (b) a new metric for evaluating DCS.


Asunto(s)
Enfermedad de Descompresión/diagnóstico por imagen , Microburbujas , Animales , Gelatina , Fantasmas de Imagen , Sensibilidad y Especificidad , Porcinos , Muslo/diagnóstico por imagen , Ultrasonografía/métodos
10.
Cogent Med ; 6(1)2019.
Artículo en Inglés | MEDLINE | ID: mdl-31754624

RESUMEN

OBJECTIVE: African American Women (AAW) are disproportionately impacted by both physical inactivity and asthma. The aims of this study were to: 1) understand barriers to physical activity among AAW with asthma; 2) obtain feedback from AAW on an evidence-based walking intervention; and 3) modify the intervention using input from AAW with asthma. METHODS: Focus groups and interviews were conducted with sedentary AAW with uncontrolled asthma to identify barriers to walking. Women also suggestions for tailoring an existing walking intervention. Qualitative data were coded using domains from the Behavior Change Wheel and guided modifications of the existing walking intervention to tailor the content for sedentary AAW with asthma. RESULTS: Six focus groups (2-4 /group) and five interviews were completed. Women (n=20) represented an obese (37 kg/m2 ± 11), middle-aged (46 years ± 15) and low-income population. Barriers to physical activity were mapped to 8 theoretical domains: 1) Limited physical capability; 2) Lack of knowledge; 3) Lack of self-monitoring skills; 4) Complex decision making processes; 5) Lack of areas to walk; 6) Lack of social support; 7) Beliefs about consequences; 8) Beliefs about capability. To target these barriers, the existing walking intervention was modified to include an asthma education session, text messages, monthly group meetings, a walking session and informational materials. CONCLUSION: AAW with asthma reported unique barriers to engaging in physical activity. An assessment of the feasibility, acceptability and efficacy of a modified intervention that addresses these barriers is warranted to address physical inactivity and poor asthma outcomes among AAW with asthma.

11.
Acad Med ; 93(5): 742-749, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29045276

RESUMEN

PURPOSE: To explore how students use and benefit from virtual patient cases (VPCs). METHOD: In academic years 2013-2014 and 2014-2015, cohorts of students in pediatrics (Peds), family medicine (FM), and internal medicine (IM) clerkships were allocated to either core required use (CRU) or self-directed use (SU) of MedU VPCs. Outcomes included number and time of case review, student perception of learning from VPCs, National Board of Medical Examiners (NBME) subject examination scores, and summative clinical ratings for medical knowledge and differential diagnoses/problem solving. Focus groups were conducted each year. Mean differences were compared by t test. RESULTS: A total of 255 students participated in the study. Mean number of cases completed by the CRU group was significantly higher than that by the SU group (13.9 vs. 3.1 for FM, 16.1 vs. 3.9 for Peds, and 10.4 vs. 1.2 for IM) (P < .001). Student-perceived value ratings of VPCs were similar between groups. Students described VPCs as time consuming but useful for supplementing clinical conditions not seen in person. Mean scores on NBME subject examinations for CRU versus SU groups were not different between groups in any clerkship, nor were there significant differences in the summative clinical ratings for medical knowledge or differential diagnosis/clinical reasoning. CONCLUSIONS: Although VPCs continue to serve an important role in exposing students to clinical conditions not seen in person, the optimal employment of this technology in clerkship pedagogy requires further exploration.


Asunto(s)
Prácticas Clínicas/métodos , Medicina Familiar y Comunitaria/educación , Medicina Interna/educación , Estudiantes de Medicina/estadística & datos numéricos , Realidad Virtual , Adulto , Competencia Clínica , Evaluación Educacional , Femenino , Grupos Focales , Humanos , Masculino
12.
J Invasive Cardiol ; 29(12): E184-E189, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29207366

RESUMEN

OBJECTIVES: The purpose of this study was to investigate the relationship between operator volume and implantable defibrillator lead failure and patient mortality at a single large implanting center. METHODS: This study analyzed the differences between high-volume and low-volume defibrillator implanters in the Pacemaker and Implantable Defibrillator Lead Survival Study ("PAIDLESS") between February 1, 1996 and December 31, 2011 at NYU Winthrop Hospital. "High-volume" was defined as performing ≥500 implants over the study period, while "low-volume" was defined as performing <500 implants. Comparisons between the procedure volume groups were performed using Fisher's Exact test, Wilcoxon rank-sum test, and Kaplan-Meier analysis as appropriate. RESULTS: Eight operators participated in the study, four of whom were high-volume operators. Of 3801 patients, a total of 3149 (83%) were operated upon by high-volume operators. Low-volume operators implanted fewer recalled leads (12% vs 42%; P<.001) and more often obtained venous access through the cephalic vein cutdown approach (63% vs 38%; P<.001) than high-volume operators. Kaplan-Meier analysis revealed shorter time to lead failure in the low-volume group (P=.02). Time to mortality was not significantly different between the high-volume and low-volume groups (P=.18). When adjusted for lead recall status, patients of high-volume operators were 43% less likely to experience lead failure compared to patients of low-volume operators. CONCLUSIONS: High-volume defibrillator implanters selected a higher percentage of recalled leads, but their patients were less likely to encounter lead failure when adjusted for lead recall status compared to low-volume operators.


Asunto(s)
Desfibriladores Implantables , Cardioversión Eléctrica , Fibrilación Ventricular , Adulto , Anciano , Desfibriladores Implantables/efectos adversos , Desfibriladores Implantables/normas , Cardioversión Eléctrica/efectos adversos , Cardioversión Eléctrica/instrumentación , Cardioversión Eléctrica/métodos , Diseño de Equipo/métodos , Diseño de Equipo/normas , Falla de Equipo/estadística & datos numéricos , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Recall de Suministro Médico , Persona de Mediana Edad , Evaluación de Procesos y Resultados en Atención de Salud , Estados Unidos , Fibrilación Ventricular/mortalidad , Fibrilación Ventricular/prevención & control
13.
J Invasive Cardiol ; 28(12): E198-E202, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27922811

RESUMEN

OBJECTIVES: The purpose of this study was to determine if implantation of multiple recalled defibrillator leads is associated with an increased risk of lead failure. BACKGROUND: The authors of the Pacemaker and Implantable Defibrillator Leads Survival Study ("PAIDLESS") have previously reported a relationship between recalled lead status, lead failure, and patient mortality. This substudy analyzes the relationship in a smaller subset of patients who received more than one recalled lead. The specific effects of having one or more recalled leads have not been previously examined. METHODS: This study analyzed lead failure and mortality of 3802 patients in PAIDLESS and compared outcomes with respect to the number of recalled leads received. PAIDLESS includes all patients at Winthrop University Hospital who underwent defibrillator lead implantation between February 1, 1996 and December 31, 2011. Patients with no recalled ICD leads, one recalled ICD lead, and two recalled ICD leads were compared using the Kaplan-Meier method and log-rank test. Sidak adjustment method was used to correct for multiple comparisons. All calculations were performed using SAS 9.4. P-values <.05 were considered statistically significant. RESULTS: This study included 4078 total ICD leads implanted during the trial period. There were 2400 leads (59%) in the no recalled leads category, 1620 leads (40%) in the one recalled lead category, and 58 leads (1%) in the two recalled leads category. No patient received more than two recalled leads. Of the leads categorized in the two recalled leads group, 12 experienced lead failures (21%), which was significantly higher (P<.001) than in the no recalled leads group (60 failures, 2.5%) and one recalled lead group (81 failures; 5%). Multivariable Cox's regression analysis found a total of six significant predictive variables for lead failure including the number of recalled leads (P<.001 for one and two recalled leads group). CONCLUSIONS: The number of recalled leads is highly predictive of lead failure. Lead-based multivariable Cox's regression analysis produced a total of six predictive variable categories for lead failure, one of which was the number of recalled leads. Kaplan-Meier analysis showed that the leads in the two recalled leads category failed faster than both the no recalled lead and one recalled lead groups. The greater the number of recalled leads to which patients are exposed, the greater the risk of lead failure.


Asunto(s)
Desfibriladores Implantables , Cardioversión Eléctrica , Falla de Equipo/estadística & datos numéricos , Recall de Suministro Médico , Marcapaso Artificial , Anciano , Desfibriladores Implantables/efectos adversos , Desfibriladores Implantables/clasificación , Desfibriladores Implantables/estadística & datos numéricos , Cardioversión Eléctrica/efectos adversos , Cardioversión Eléctrica/instrumentación , Cardioversión Eléctrica/métodos , Diseño de Equipo , Análisis de Falla de Equipo/métodos , Análisis de Falla de Equipo/estadística & datos numéricos , Femenino , Cardiopatías/terapia , Humanos , Masculino , Persona de Mediana Edad , Marcapaso Artificial/efectos adversos , Marcapaso Artificial/clasificación , Marcapaso Artificial/estadística & datos numéricos , Estados Unidos
14.
J Neurosci ; 20(8): 2988-93, 2000 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-10751451

RESUMEN

The Drosophila slowpoke gene encodes a BK-type calcium-activated potassium channel. Null mutations in slowpoke perturb the signaling properties of neurons and muscles and cause behavioral defects. The animals fly very poorly compared with wild-type strains and, after exposure to a bright but cool light or a heat pulse, exhibit a "sticky-feet" phenotype. Expression of slowpoke arises from five transcriptional promoters that express the gene in neural, muscle, and epithelial tissues. A chromosomal deletion (ash2(18)) has been identified that removes the neuronal promoters but not the muscle-tracheal cell promoter. This deletion complements the flight defect of slowpoke null mutants but not the sticky-feet phenotype. Electrophysiological assays confirm that the ash2(18) chromosome restores normal electrical properties to the flight muscle. This suggests that the flight defect arises from a lack of slowpoke expression in muscle, whereas the sticky-feet phenotype arises from a lack of expression in nervous tissue.


Asunto(s)
Potenciales de Acción/genética , Vuelo Animal/fisiología , Eliminación de Gen , Canales de Potasio/genética , Regiones Promotoras Genéticas/genética , Animales , Drosophila , Fenotipo
15.
J Clin Oncol ; 2(5): 443-6, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6587017

RESUMEN

Evaluation of the ultrastructure of material obtained by endomyocardial biopsy has been proposed as a means to evaluate patients for impending anthracycline cardiotoxicity. Eighteen biopsies obtained from 13 patients (age, 3-18 years) are reported. Twelve biopsy procedures were done to evaluate the cardiac status on reaching a cumulative dose of 400 mg/m2 and three patients had six subsequent biopsies after having received significantly more drug or receiving radiation therapy to the lungs or mediastinum. Scores were assigned to the tissue obtained and used to guide the decision to continue or stop anthracycline therapy. Three patients with abnormal cardiac studies at low cumulative doses, five of whom had received greater than 400 mg/m2 and three of whom had received considerably higher doses and thoracic irradiation were given more drug without incident. Two specimens were interpreted to indicate avoidance of further anthracycline and two patients were cautiously given more despite evidence of mild myocardial damage. These results indicate that endomyocardial biopsies can be performed on a pediatric population with a reasonable complication rate. Further studies should be undertaken to evaluate its usefulness as a means to predict and avoid anthracycline cardiomyopathy.


Asunto(s)
Endocardio/efectos de los fármacos , Cardiopatías/inducido químicamente , Neoplasias/tratamiento farmacológico , Adolescente , Antibióticos Antineoplásicos , Biopsia/efectos adversos , Cateterismo Cardíaco/efectos adversos , Niño , Preescolar , Endocardio/patología , Estudios de Evaluación como Asunto , Cardiopatías/prevención & control , Humanos , Naftacenos/efectos adversos , Neumotórax/etiología , Sepsis/etiología
16.
J Invasive Cardiol ; 27(6): 292-300, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26028656

RESUMEN

OBJECTIVES: The purpose of the study was to examine survival in the implantable defibrillator subset of implanted leads at a large-volume implanting hospital. BACKGROUND: Implantable lead survival has been the subject of many multicenter studies over the past decade. Fewer large implanting volume single-hospital studies have examined defibrillator lead failure as it relates to patient survival and lead construction. METHODS: This investigator-initiated retrospective study examined defibrillator lead failure in those who underwent implantation of a defibrillator between February 1, 1996 and December 31, 2011. Lead failure was defined as: failure to capture/sense, abnormal pacing and/or defibrillator impedance, visual insulation defect or lead fracture, extracardiac stimulation, cardiac perforation, tricuspid valve entrapment, lead tip fracture and/or lead dislodgment. Patient characteristics, implant approach, lead manufacturers, lead models, recalled status, patient mortality, and core lead design elements were compared using methods that include Kaplan Meier analysis, univariate and multivariable Cox regression models. RESULTS: A total of 4078 defibrillator leads were implanted in 3802 patients (74% male; n = 2812) with a mean age of 70 ± 13 years at Winthrop University Hospital. Lead manufacturers included: Medtronic: [n = 1834; 801 recalled]; St. Jude Medical: [n = 1707; 703 recalled]; Boston Scientific: [n = 537; 0 recalled]. Kaplan-Meier analysis adjusted for multiple comparisons revealed that both Boston Scientific's and St. Jude Medical's leads had better survival than Medtronic's leads (P<.001 and P=.01, respectively). Lead survival was comparable between Boston Scientific and St. Jude Medical (P=.80). A total of 153 leads failed (3.5% of all leads) during the study. There were 99 lead failures from Medtronic (5.4% failure rate); 56 were recalled Sprint Fidelis leads. There were 36 lead failures from St. Jude (2.1% failure rate); 20 were recalled Riata or Riata ST leads. There were 18 lead failures from Boston Scientific (3.35% failure rate); none were recalled. Kaplan Meier analysis also showed lead failure occurred sooner in the recalled leads (P=.01). A total of 1493 patients died during the study (mechanism of death was largely unknown). There was a significant increase in mortality in the recalled lead group as compared with non-recalled leads (P=.01), but no significant difference in survival when comparing recalled leads from Medtronic with St. Jude Medical (P=.67). A multivariable Cox regression model revealed younger age, history of percutaneous coronary intervention, baseline rhythm other than atrial fibrillation or atrial flutter, combination polyurethane and silicone lead insulation, a second defibrillation coil, and recalled lead status all contributed to lead failure. CONCLUSION: This study demonstrated a significantly improved lead performance in the Boston Scientific and St. Jude leads as compared with Medtronic leads. Some lead construction variables (insulation and number of coils) also had a significant impact on lead failure, which was independent of the manufacturer. Recalled St. Jude leads performed better than recalled Medtronic leads in our study. Recalled St. Jude leads had no significant difference in lead failure when compared with the other manufacturer's non-recalled leads. Defibrillator recalled lead status was associated with an increased mortality as compared with non-recalled leads. This correlation was independent of the lead manufacturer and clinically significant even when considering known mortality risk factors. These results must be tempered by the largely unknown mechanism of death in these patients.


Asunto(s)
Arritmias Cardíacas/terapia , Desfibriladores Implantables/efectos adversos , Recall de Suministro Médico , Diseño de Prótesis/instrumentación , Falla de Prótesis , Factores de Edad , Anciano , Arritmias Cardíacas/mortalidad , Desfibriladores Implantables/estadística & datos numéricos , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Ensayos Clínicos Controlados no Aleatorios como Asunto , Marcapaso Artificial , Estudios Retrospectivos
17.
J Invasive Cardiol ; 27(12): 530-4, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26630641

RESUMEN

OBJECTIVES: The purpose of this study was to investigate the influences of gender and age on defibrillator lead failure and patient mortality. BACKGROUND: The specific influences of gender and age on defibrillator lead failure have not previously been investigated. METHODS: This study analyzed the differences in gender and age in relation to defibrillator lead failure and mortality of patients in the Pacemaker and Implantable Defibrillator Leads Survival Study ("PAIDLESS"). PAIDLESS includes all patients at Winthrop University Hospital who underwent defibrillator lead implantation between February 1, 1996 and December 31, 2011. Male and female patients were compared within each age decile, beginning at 15 years old, to analyze lead failure and patient mortality. Statistical analyses were performed using Wilcoxon rank-sum test, Fisher's exact test, Kaplan-Meier analysis, and multivariable Cox regression models. P<.05 was considered statistically significant. No correction for multiple comparisons was performed for the subgroup analyses. RESULTS: A total of 3802 patients (2812 men and 990 women) were included in the analysis. The mean age was 70 ± 13 years (range, 15-94 years). Kaplan-Meier analysis found that between 45 and 54 years of age, leads implanted in women failed significantly faster than in men (P=.03). Multivariable Cox regression models were built to validate this finding, and they confirmed that male gender was an independent protective factor of lead failure in the 45 to 54 years group (for male gender: HR, 0.37; 95% confidence interval, 0.14-0.96; P=.04). Lead survival time for women in this age group was 13.4 years (standard error, 0.6), while leads implanted in men of this age group survived 14.7 years (standard error, 0.3). Although there were significant differences in lead failure, no differences in mortality between the genders were found for any ages or within each decile. CONCLUSIONS: This study is the first to compare defibrillator lead failure and patient mortality in relation to gender and age deciles at a single large implanting center. Within the 45 to 54 years group, leads implanted in women failed faster than in men. Male gender was found to be an independent protective factor in lead survival. This study emphasizes the complex interplay between gender and age with respect to implantable defibrillator lead failure and mortality.


Asunto(s)
Desfibriladores Implantables , Cardiopatías/mortalidad , Cardiopatías/terapia , Marcapaso Artificial , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Diseño de Equipo , Falla de Equipo , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores Sexuales , Tasa de Supervivencia/tendencias , Estados Unidos/epidemiología , Adulto Joven
18.
J Med Chem ; 21(11): 1168-71, 1978 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-214556

RESUMEN

Three general methods for the synthesis of derivatives of the bis-alkylating agent, myleran [1,4-bis(methane-sulfonoxy)butane (1)], are presented. These derivatives contain a lipophilic group attached to the 2 position of 1,4-bis(methanesulfonoxy)butane by means of a sulfonyl function. As examples of the scope of the methods, the synthesis of seven such derivatives (12a-g) is presented. All seven were inactive against L1210 and P388 leukemia in the mouse.


Asunto(s)
Alquilantes/síntesis química , Mesilatos/síntesis química , Alquilantes/uso terapéutico , Animales , Leucemia L1210/tratamiento farmacológico , Leucemia Experimental/tratamiento farmacológico , Mesilatos/farmacología , Mesilatos/uso terapéutico , Ratones
19.
Neuroscience ; 125(3): 651-61, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15099679

RESUMEN

TorsinA is a novel protein identified in the search for mutations underlying the human neurologic movement disorder, early onset torsion dystonia. Relatively little is understood about the normal function of torsinA or the physiological effects of the codon deletion associated with most cases of disease. Overexpression of wild-type torsinA in cultured cells by DNA transfection results in a reticular distribution of immunoreactive protein that co-localizes with endoplasmic reticulum resident chaperones, while the dystonia-related mutant form accumulates within concentric membrane whorls and nuclear-associated membrane stacks. In this study we examined the biogenesis of mutant torsinA-positive membrane inclusions using tetracycline-regulated herpes simplex virus amplicon vectors. At low expression levels, mutant torsinA was localized predominantly around the nucleus, while at high levels it was also concentrated within cytosolic spheroid inclusions. In contrast, the distribution of wild-type torsinA did not vary, appearing diffuse and reticular at all expression levels. These observations are consistent with descriptions of inducible membrane synthesis in other systems in which cytosolic membrane whorls are derived from multilayered membrane stacks that first form around the nuclear envelope. These results also suggest that formation of mutant torsinA-positive inclusions occurs at high expression levels in culture, whereas the perinuclear accumulation of the mutant protein is present even at low expression levels that are more likely to resemble those of the endogenous protein. These nuclear-associated membrane structures enriched in mutant torsinA may therefore be of greater relevance to understanding how the dystonia-related mutation compromises cellular physiology.


Asunto(s)
Proteínas Portadoras/metabolismo , Núcleo Celular/metabolismo , Cuerpos de Inclusión/metabolismo , Membranas Intracelulares/metabolismo , Chaperonas Moleculares/metabolismo , Orgánulos/metabolismo , Animales , Biomarcadores , Proteínas Portadoras/genética , Línea Celular , Núcleo Celular/genética , Núcleo Celular/patología , Citosol/metabolismo , Citosol/patología , Distonía Muscular Deformante/genética , Distonía Muscular Deformante/metabolismo , Distonía Muscular Deformante/fisiopatología , Genes Reporteros/genética , Vectores Genéticos/genética , Herpes Simple/genética , Humanos , Cuerpos de Inclusión/genética , Cuerpos de Inclusión/patología , Membranas Intracelulares/patología , Chaperonas Moleculares/genética , Mutación/genética , Membrana Nuclear/metabolismo , Membrana Nuclear/patología , Orgánulos/genética , Orgánulos/patología , Tetraciclina/farmacología , Transgenes/genética
20.
Pediatrics ; 61(5): 711-5, 1978 May.
Artículo en Inglés | MEDLINE | ID: mdl-662509

RESUMEN

The prevalence of serologic markers for hepatitis B virus (HBV) among 188 patients and 158 employees in a pediatric oncology unit was evaluated. Evidence of past or present HBV infection was detected in 33 patients (18%) and in 25 employees (16%). The prevalence was higher among patients receiving chemotherapy (19%) than among those not receiving chemotherapy (7%). The prevalence of HBV serologic markers, while much higher than generally found among healthy children in the United States, was low compared to previously reported prevalences in such settings, and may reflect the use in recent years of blood and blood products screened by "third generation" methods (radioimmunoassay and reversed passive hemagglutination) for hepatitis B surface antigen and the use of all volunteer blood donors. This prevalence suggests that perhaps there is less urgent need for the use of hepatitis B immune globulin and hepatitis B vaccine (when it becomes available) in oncology units than had been anticipated from earlier data in oncology units.


Asunto(s)
Hepatitis B/epidemiología , Neoplasias , Pediatría , Adolescente , Adulto , Niño , Preescolar , Femenino , Hepatitis B/sangre , Hepatitis B/prevención & control , Hepatitis B/transmisión , Virus de la Hepatitis B , Unidades Hospitalarias , Humanos , Inmunoglobulinas/uso terapéutico , Lactante , Recién Nacido , Masculino , Personal de Hospital , Riesgo , Vacunas Virales
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA