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1.
Pacing Clin Electrophysiol ; 37(12): 1671-80, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25081578

RESUMEN

BACKGROUND: High-burden premature ventricular contractions (PVCs) may be an important determinant of heart failure (HF) in patients presenting for PVC ablation. The prevalence and characteristics of high-burden PVC patients outside this setting remain unknown. We, therefore, sought to determine predictors of high-burden PVCs and, among high-burden PVC patients, predictors of HF. METHODS: We identified all patients undergoing a 24-48-hour Holter study showing at least 20% PVCs between 2005 and 2013 at the University of California, San Francisco. Three time-matched controls undergoing Holter monitoring were selected for each high-burden PVC patient. Medical records were reviewed and test characteristics of PVC counts from 12-lead electrocardiograms (ECG) as predictors of high-burden PVC Holters were analyzed. RESULTS: Among 5,091 participants, 66 (1.3%) exhibited at least 20% PVCs. After multivariate adjustment, high-burden PVC patients had a three-fold greater odds of HF (odds ratio [OR] 3.15; 95% confidence interval [CI] 1.28-6.50; P = 0.005) and 10-fold greater odds of having a first-degree family member with sudden death (OR 9.97; 95% CI 1.78-60.8; P = 0.011). The C-statistic for the number of PVCs on 12-lead electrocardiogram as a predictor of high-burden PVCs was 0.7949. Among high-burden PVC patients, HF was associated with a history of coronary artery bypass grafting (OR 11.76; 95% CI 1.30-106.49; P = 0.028). CONCLUSION: Among all undergoing Holter monitoring, 1.3% exhibited high-burden PVCs, a phenomenon associated with HF and a first-degree family history of sudden death. In an analysis restricted to high-burden PVC patients, a history of coronary artery bypass grafting was a predictor of HF.


Asunto(s)
Complejos Prematuros Ventriculares/diagnóstico , Estudios Transversales , Electrocardiografía Ambulatoria , Femenino , Insuficiencia Cardíaca/etiología , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Complejos Prematuros Ventriculares/complicaciones , Complejos Prematuros Ventriculares/fisiopatología
2.
Ann Intern Med ; 159(11): 721-8, 2013 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-24297188

RESUMEN

BACKGROUND: Atrial fibrillation (AF) prediction models have unclear clinical utility given the absence of AF prevention therapies and the immutability of many risk factors. Premature atrial contractions (PACs) play a critical role in AF pathogenesis and may be modifiable. OBJECTIVE: To investigate whether PAC count improves model performance for AF risk. DESIGN: Prospective cohort study. SETTING: 4 U.S. communities. PATIENTS: A random subset of 1260 adults without prevalent AF enrolled in the Cardiovascular Health Study between 1989 and 1990. MEASUREMENTS: The PAC count was quantified by 24-hour electrocardiography. Participants were followed for the diagnosis of incident AF or death. The Framingham AF risk algorithm was used as the comparator prediction model. RESULTS: In adjusted analyses, doubling the hourly PAC count was associated with a significant increase in AF risk (hazard ratio, 1.17 [95% CI, 1.13 to 1.22]; P < 0.001) and overall mortality (hazard ratio, 1.06 [CI, 1.03 to 1.09]; P < 0.001). Compared with the Framingham model, PAC count alone resulted in similar AF risk discrimination at 5 and 10 years of follow-up and superior risk discrimination at 15 years. The addition of PAC count to the Framingham model resulted in significant 10-year AF risk discrimination improvement (c-statistic, 0.65 vs. 0.72; P < 0.001), net reclassification improvement (23.2% [CI, 12.8% to 33.6%]; P < 0.001), and integrated discrimination improvement (5.6% [CI, 4.2% to 7.0%]; P < 0.001). The specificity for predicting AF at 15 years exceeded 90% for PAC counts more than 32 beats/h. LIMITATION: This study does not establish a causal link between PACs and AF. CONCLUSION: The addition of PAC count to a validated AF risk algorithm provides superior AF risk discrimination and significantly improves risk reclassification. Further study is needed to determine whether PAC modification can prospectively reduce AF risk. PRIMARY FUNDING SOURCE: American Heart Association, Joseph Drown Foundation, and National Institutes of Health.


Asunto(s)
Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Función Atrial/fisiología , Modelos Estadísticos , Contracción Miocárdica/fisiología , Anciano , Causas de Muerte , Electrocardiografía , Femenino , Humanos , Masculino , Estudios Prospectivos , Medición de Riesgo
3.
NPJ Parkinsons Dis ; 10(1): 124, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918417

RESUMEN

Striosomes and matrix are two compartments that comprise the striatum, each having its own distinct immunohistochemical properties, function, and connectivity. It is currently not clear whether prodromal or early manifest Parkinson's disease (PD) is associated with any striatal matrix or striosomal abnormality. Recently, a method of striatal parcellation using probabilistic tractography has been described and validated, using the distinct connectivity of these two compartments to identify voxels with striosome- and matrix-like connectivity. The goal of this study was to use this approach in tandem with DAT-SPECT, a method used to quantify the level of nigrostriatal denervation, to analyze the striatum in populations of de novo diagnosed, treatment-naïve patients with PD, isolated REM behavioral disorder (iRBD) patients, and healthy controls. We discovered a shift in striatal connectivity, which showed correlation with nigrostriatal denervation. Patients with PD exhibited a significantly higher matrix-like volume and associated connectivity than healthy controls and higher matrix-associated connectivity than iRBD patients. In contrast, the side with less pronounced nigrostriatal denervation in PD and iRBD patients showed a decrease in striosome-like volume and associated connectivity indices. These findings could point to a compensatory neuroplastic mechanism in the context of nigrostriatal denervation and open a new avenue in the investigation of the pathophysiology of Parkinson's disease.

4.
Br J Cancer ; 108(4): 766-70, 2013 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-23412098

RESUMEN

BACKGROUND: To evaluate the efficacy and tolerability of the urokinase plasminogen activator (uPA) inhibitor upamostat in combination with gemcitabine in locally advanced pancreatic adenocarcinoma (LAPC). METHODS: Within a prospective multicenter study, LAPC patients were randomly assigned to receive 1000 mg m(-2) of gemcitabine IV weekly either alone (arm A) or in combination with 200 mg (arm B) or 400 mg (arm C) oral upamostat daily. Efficacy endpoints of this proof-of-concept study included response rate, time to first metastasis, progression-free and overall survival (OS). RESULTS: Of the 95 enroled patients, 85 were evaluable for response and 93 for safety. Median OS was 12.5 months (95% CI 8.2-18.2) in arm C, 9.7 months (95% CI 8.4-17.1) in arm B and 9.9 months (95% CI 7.4-12.1) in arm A; corresponding 1-year survival rates were 50.6%, 40.7% and 33.9%, respectively. More patients achieved a partial remission (confirmed responses by RECIST) with upamostat combination therapy (arm C: 12.9%; arm B: 7.1%; arm A: 3.8%). Overall, only 12 patients progressed by developing detectable distant metastasis (arm A: 4, arm B: 6, arm C: 2). The most common adverse events considered to be related to upamostat were asthenia, fever and nausea. CONCLUSION: In this proof-of-concept study targeting the uPA system in LAPC, the addition of upamostat to gemcitabine was tolerated well; similar survival results were observed for the three treatment arms.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Proteínas Sanguíneas/administración & dosificación , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamiento farmacológico , Piperazinas/administración & dosificación , Sulfonamidas/administración & dosificación , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Desoxicitidina/administración & dosificación , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oximas , Gemcitabina
5.
Cogn Neurodyn ; 17(4): 985-1008, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37522034

RESUMEN

Facial Expression Recognition (FER) is the basis for many applications including human-computer interaction and surveillance. While developing such applications, it is imperative to understand human emotions for better interaction with machines. Among many FER models developed so far, Ensemble Stacked Convolution Neural Networks (ES-CNN) showed an empirical impact in improving the performance of FER on static images. However, the existing ES-CNN based FER models trained with features extracted from the entire face, are unable to address the issues of ambient parameters such as pose, illumination, occlusions. To mitigate the problem of reduced performance of ES-CNN on partially occluded faces, a Component based ES-CNN (CES-CNN) is proposed. CES-CNN applies ES-CNN on action units of individual face components such as eyes, eyebrows, nose, cheek, mouth, and glabella as one subnet of the network. Max-Voting based ensemble classifier is used to ensemble the decisions of the subnets in order to obtain the optimized recognition accuracy. The proposed CES-CNN is validated by conducting experiments on benchmark datasets and the performance is compared with the state-of-the-art models. It is observed from the experimental results that the proposed model has a significant enhancement in the recognition accuracy compared to the existing models.

6.
Artículo en Inglés | MEDLINE | ID: mdl-37107837

RESUMEN

Microplastics (MP) are plastic particles less than 5 mm in size. There are two categories of MP: primary and secondary. Primary or microscopic-sized MP are intentionally produced material. Fragmentation of large plastic debris through physical, chemical, and oxidative processes creates secondary MP, the most abundant type in the environment. Microplastic pollution has become a global environmental problem due to their abundance, poor biodegradability, toxicological properties, and negative impact on aquatic and terrestrial organisms including humans. Plastic debris enters the aquatic environment via direct dumping or uncontrolled land-based sources. While plastic debris slowly degrades into MP, wastewater and stormwater outlets discharge a large amount of MP directly into water bodies. Additionally, stormwater carries MP from sources such as tire wear, artificial turf, fertilizers, and land-applied biosolids. To protect the environment and human health, the entry of MP into the environment must be reduced or eliminated. Source control is one of the best methods available. The existing and growing abundance of MP in the environment requires the use of multiple strategies to combat pollution. These strategies include reducing the usage, public outreach to eliminate littering, reevaluation and use of new wastewater treatment and sludge disposal methods, regulations on macro and MP sources, and a wide implementation of appropriate stormwater management practices such as filtration, bioretention, and wetlands.


Asunto(s)
Plásticos , Contaminantes Químicos del Agua , Humanos , Plásticos/química , Microplásticos/toxicidad , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Aguas Residuales
8.
Physiol Res ; 68(Suppl 4): S453-S458, 2019 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-32118476

RESUMEN

Neuromelanin (NM) is a black pigment located in the brain in substantia nigra pars compacta (SN) and locus coeruleus. Its loss is directly connected to the loss of nerve cells in this part of the brain, which plays a role in Parkinson's Disease. Magnetic resonance imaging (MRI) is an ideal tool to monitor the amount of NM in the brain in vivo. The aim of the study was the development of tools and methodology for the quantification of NM in a special neuromelanin-sensitive MRI images. The first approach was done by creating regions of interest, corresponding to the anatomical position of SN based on an anatomical atlas and determining signal intensity threshold. By linking the anatomical and signal intensity information, we were able to segment the SN. As a second approach, the neural network U-Net was used for the segmentation of SN. Subsequently, the volume characterizing the amount of NM in the SN region was calculated. To verify the method and the assumptions, data available from various patient groups were correlated. The main benefit of this approach is the observer-independency of quantification and facilitation of the image processing process and subsequent quantification compared to the manual approach. It is ideal for automatic processing many image sets in one batch.


Asunto(s)
Aprendizaje Profundo , Imagen por Resonancia Magnética/métodos , Melaninas/análisis , Sustancia Negra/diagnóstico por imagen , Sinucleinopatías/diagnóstico por imagen , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Síntomas Prodrómicos
10.
Am J Cardiol ; 118(5): 714-9, 2016 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-27448684

RESUMEN

Atrial fibrillation (AF) is likely secondary to multiple different pathophysiological mechanisms that are increasingly but incompletely understood. Motivated by the hypothesis that 3 previously described electrocardiographic predictors of AF identify distinct AF mechanisms, we sought to determine if these electrocardiographic findings independently predict incident disease. Among Cardiovascular Health Study participants without prevalent AF, we determined whether left anterior fascicular block (LAFB), a prolonged QTC, and atrial premature complexes (APCs) each predicted AF after adjusting for each other. We then calculated the attributable risk in the exposed for each electrocardiographic marker. LAFB and QTC intervals were assessed on baseline 12-lead electrocardiogram (n = 4,696). APC count was determined using 24-hour Holter recordings obtained in a random subsample (n = 1,234). After adjusting for potential confounders and each electrocardiographic marker, LAFB (hazard ratio [HR] 2.1, 95% confidence interval [CI] 1.1 to 3.9, p = 0.023), a prolonged QTC (HR 2.5, 95% CI 1.4 to 4.3, p = 0.002), and every doubling of APC count (HR 1.2, 95% CI 1.1 to 1.3, p <0.001) each remained independently predictive of incident AF. The attributable risk of AF in the exposed was 35% (95% CI 13% to 52%) for LAFB, 25% (95% CI 0.6% to 44%) for a prolonged QTC, and 34% (95% CI 26% to 42%) for APCs. In conclusion, in a community-based cohort, 3 previously established electrocardiogram-derived AF predictors were each independently associated with incident AF, suggesting that they may represent distinct mechanisms underlying the disease.


Asunto(s)
Fibrilación Atrial/diagnóstico , Electrocardiografía , Anciano , Fibrilación Atrial/fisiopatología , Complejos Atriales Prematuros/diagnóstico , Índice de Masa Corporal , Estudios de Cohortes , Electrocardiografía/métodos , Femenino , Humanos , Incidencia , Valor Predictivo de las Pruebas , Prevalencia , Medición de Riesgo , Factores de Riesgo , Sensibilidad y Especificidad
11.
J Am Coll Cardiol ; 66(2): 101-9, 2015 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-26160626

RESUMEN

BACKGROUND: Studies of patients presenting for catheter ablation suggest that premature ventricular contractions (PVCs) are a modifiable risk factor for congestive heart failure (CHF). The relationship among PVC frequency, incident CHF, and mortality in the general population remains unknown. OBJECTIVES: The goal of this study was to determine whether PVC frequency ascertained using a 24-h Holter monitor is a predictor of a decrease in the left ventricular ejection fraction (LVEF), incident CHF, and death in a population-based cohort. METHODS: We studied 1,139 Cardiovascular Health Study (CHS) participants who were randomly assigned to 24-h ambulatory electrocardiography (Holter) monitoring and who had a normal LVEF and no history of CHF. PVC frequency was quantified using Holter studies, and LVEF was measured from baseline and 5-year echocardiograms. Participants were followed for incident CHF and death. RESULTS: Those in the upper quartile versus the lowest quartile of PVC frequency had a multivariable-adjusted, 3-fold greater odds of a 5-year decrease in LVEF (odds ratio [OR]: 3.10; 95% confidence interval [CI]: 1.42 to 6.77; p = 0.005), a 48% increased risk of incident CHF (HR: 1.48; 95% CI: 1.08 to 2.04; p = 0.02), and a 31% increased risk of death (HR: 1.31; 95% CI: 1.06 to 1.63; p = 0.01) during a median follow-up of >13 years. Similar statistically significant results were observed for PVCs analyzed as a continuous variable. The specificity for the 15-year risk of CHF exceeded 90% when PVCs included at least 0.7% of ventricular beats. The population-level risk for incident CHF attributed to PVCs was 8.1% (95% CI: 1.2% to 14.9%). CONCLUSIONS: In a population-based sample, a higher frequency of PVCs was associated with a decrease in LVEF, an increase in incident CHF, and increased mortality. Because of the capacity to prevent PVCs through medical or ablation therapy, PVCs may represent a modifiable risk factor for CHF and death.


Asunto(s)
Insuficiencia Cardíaca/diagnóstico , Complejos Prematuros Ventriculares/complicaciones , Anciano , Ablación por Catéter , Ecocardiografía , Electrocardiografía Ambulatoria , Femenino , Predicción , Insuficiencia Cardíaca/mortalidad , Humanos , Masculino , Factores de Riesgo , Volumen Sistólico , Complejos Prematuros Ventriculares/mortalidad
12.
FEBS Lett ; 309(3): 288-92, 1992 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-1516699

RESUMEN

We have isolated and characterized cDNAs from Hydra which encode antistasin, a potent inhibitor of factor Xa in the vertebrate blood clotting cascade. Hydra antistasin is expressed in gland cells and represents a major class of transcripts from Hydra's head. Sequence analysis revealed that Hydra antistasin contains 6 internal repeats of a 25-26 amino acid sequence with a highly conserved pattern of 6 cysteine and 2 glycine residues identical to that in leech antistasin. Conservation of antistasin in a lower metazoan provides a potential link between the vertebrate and invertebrate coagulation systems.


Asunto(s)
Anticoagulantes/metabolismo , Regulación de la Expresión Génica , Hydra/genética , Hormonas de Invertebrados/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Clonación Molecular , ADN , Hydra/crecimiento & desarrollo , Hydra/metabolismo , Hormonas de Invertebrados/metabolismo , Datos de Secuencia Molecular , Homología de Secuencia de Ácido Nucleico
13.
Folia Biol (Praha) ; 49(2): 74-7, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12779016

RESUMEN

cG250 is an IgG1 kappa light-chain chimeric monoclonal antibody that binds to a cell surface antigen found on 95% of clear-cell renal cancer. A multicentre phase II study was performed to evaluate the safety and efficacy of repeated doses of cG250. Thirty-six patients with metastatic RCC were included. All patients were nephrectomized for the primary tumour. Twenty-one patients were pretreated (e.g. with IL-2, IFN-alpha). A weekly dose of 50 mg cG250 was given by i.v. infusion for 12 weeks. Patients with SD or tumour response (PR, CR) after 12 weeks of treatment could receive additional treatment for 8 more weeks. None of the 36 enrolled patients had any cG250 grade III or IV toxicity. Only three patients had grade II toxicity possibly related to the study medication. ELISA testing gave no evidence for relevant amounts of HACA. Eleven patients presented with SD and ten were eligible for extension treatment. After the end of the study in the follow-up period, one patient demonstrated a CR in week 38 and another patient with SD showed a significant reduction of the overall tumour load in week 44. Six additional patients with progressive disease at study entry were stable for more than six months after the treatment start. The weekly schedule of i.v. cG250 in patients with metastatic RCC was safe, very well tolerated and non-immunogenic in a 12-week treatment regimen. cG250 showed anti-tumour activity.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/uso terapéutico , Carcinoma de Células Renales/tratamiento farmacológico , Neoplasias Renales/tratamiento farmacológico , Proteínas Recombinantes de Fusión/uso terapéutico , Adulto , Anciano , Antígenos de Superficie/efectos de los fármacos , Antígenos de Superficie/inmunología , Carcinoma de Células Renales/inmunología , Progresión de la Enfermedad , Femenino , Humanos , Interferón-alfa/uso terapéutico , Interleucina-2/uso terapéutico , Neoplasias Renales/inmunología , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia/tratamiento farmacológico , Metástasis de la Neoplasia/inmunología , Metástasis de la Neoplasia/prevención & control , Estudios Prospectivos , Resultado del Tratamiento
14.
J Am Heart Assoc ; 2(5): e000428, 2013 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-24045120

RESUMEN

BACKGROUND: Transseptal puncture is a critical step in achieving left atrial (LA) access for a variety of cardiac procedures. Although the mechanical Brockenbrough needle has historically been used for this procedure, a needle employing radiofrequency (RF) energy has more recently been approved for clinical use. We sought to investigate the comparative effectiveness of an RF versus conventional needle for transseptal LA access. METHODS AND RESULTS: In this prospective, single-blinded, controlled trial, 72 patients were randomized in a 1:1 fashion to an RF versus conventional (BRK-1) transseptal needle. In an intention-to-treat analysis, the primary outcome was time required for transseptal LA access. Secondary outcomes included failure of the assigned needle, visible plastic dilator shavings from needle introduction, and any procedural complication. The median transseptal puncture time was 68% shorter using the RF needle compared with the conventional needle (2.3 minutes [interquartile range {IQR}, 1.7 to 3.8 minutes] versus 7.3 minutes [IQR, 2.7 to 14.1 minutes], P = 0.005). Failure to achieve transseptal LA access with the assigned needle was less common using the RF versus conventional needle (0/36 [0%] versus 10/36 [27.8%], P < 0.001). Plastic shavings were grossly visible after needle advancement through the dilator and sheath in 0 (0%) RF needle cases and 12 (33.3%) conventional needle cases (P < 0.001). There were no differences in procedural complications (1/36 [2.8%] versus 1/36 [2.8%]). CONCLUSIONS: Use of an RF needle resulted in shorter time to transseptal LA access, less failure in achieving transseptal LA access, and fewer visible plastic shavings.


Asunto(s)
Ablación por Catéter/instrumentación , Atrios Cardíacos/cirugía , Agujas , Punciones/instrumentación , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Ondas de Radio , Método Simple Ciego
15.
Heart Rhythm ; 10(10): 1562-8, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23872693

RESUMEN

BACKGROUND: Abnormal atrial repolarization is important in the development of atrial fibrillation (AF), but no direct measurement is available in clinical medicine. OBJECTIVE: To determine whether the QT interval, a marker of ventricular repolarization, could be used to predict incident AF. METHODS: We examined a prolonged QT interval corrected by using the Framingham formula (QT(Fram)) as a predictor of incident AF in the Atherosclerosis Risk in Communities (ARIC) study. The Cardiovascular Health Study (CHS) and Health, Aging, and Body Composition (ABC) study were used for validation. Secondary predictors included QT duration as a continuous variable, a short QT interval, and QT intervals corrected by using other formulas. RESULTS: Among 14,538 ARIC study participants, a prolonged QT(Fram) predicted a roughly 2-fold increased risk of AF (hazard ratio [HR] 2.05; 95% confidence interval [CI] 1.42-2.96; P < .001). No substantive attenuation was observed after adjustment for age, race, sex, study center, body mass index, hypertension, diabetes, coronary disease, and heart failure. The findings were validated in Cardiovascular Health Study and Health, Aging, and Body Composition study and were similar across various QT correction methods. Also in the ARIC study, each 10-ms increase in QT(Fram) was associated with an increased unadjusted (HR 1.14; 95% CI 1.10-1.17; P < .001) and adjusted (HR 1.11; 95% CI 1.07-1.14; P < .001) risk of AF. Findings regarding a short QT interval were inconsistent across cohorts. CONCLUSIONS: A prolonged QT interval is associated with an increased risk of incident AF.


Asunto(s)
Fibrilación Atrial/epidemiología , Síndrome de QT Prolongado/complicaciones , Síndrome de QT Prolongado/fisiopatología , Anciano , Fibrilación Atrial/diagnóstico , Estudios de Cohortes , Electrocardiografía , Femenino , Humanos , Incidencia , Síndrome de QT Prolongado/diagnóstico , Masculino , Persona de Mediana Edad , Factores de Riesgo
16.
Am J Cardiol ; 110(3): 364-8, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-22521307

RESUMEN

Alcohol and vagal activity may be important triggers for paroxysmal atrial fibrillation (PAF), but it remains unknown if these associations occur more often than would be expected by chance alone because of the lack of a comparator group in previous studies. We compared self-reported frequency of these triggers in patients with PAF to those with other supraventricular tachycardias (SVTs). Consecutive consenting patients presenting for electrophysiology procedures at a single university medical center underwent a structured interview regarding arrhythmia triggers. Two hundred twenty-three patients with a documented arrhythmia (133 with PAF and 90 with SVT) completed the survey. After multivariable adjustment, patients with PAF had a 4.42 greater odds (95% confidence interval [CI] 1.35 to 14.44) of reporting alcohol consumption (p = 0.014) and a 2.02 greater odds (95% CI 1.02 to 4.00) of reporting vagal activity (p = 0.044) as an arrhythmia trigger compared to patients with SVT. In patients with PAF, drinking primarily beer was associated with alcohol as a trigger (odds ratio [OR] 4.49, 95% CI 1.41 to 14.28, p = 0.011), whereas younger age (OR 0.68, 95% CI 0.49 to 0.95, p = 0.022) and a family history of AF (OR 5.73, 95% CI 1.21 to 27.23, p = 0.028) each were independently associated with having vagal activity provoke an episode. Patients with PAF and alcohol triggers were more likely to have vagal triggers (OR 10.32, 95% CI 1.05 to 101.42, p = 0.045). In conclusion, alcohol consumption and vagal activity elicit PAF significantly more often than SVT. Alcohol and vagal triggers often were found in the same patients with PAF, raising the possibility that alcohol may precipitate AF by vagal mechanisms.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Fibrilación Atrial/etiología , Taquicardia Paroxística/etiología , Nervio Vago/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Desencadenantes , Autoinforme
17.
J Urol ; 175(1): 57-62, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16406869

RESUMEN

PURPOSE: WX-G250 is a chimeric monoclonal antibody that binds to carbonic anhydrase IX(G250/MN), which is present on greater than 95% of RCCs of the clear cell subtype. The suggested working mechanism of WX-G250 is by ADCC. Because the number of activated ADCC effector cells can be increased by a low dose interleukin-2 pulsing schedule, a multicenter study was initiated to investigate whether WX-G250 combined with LD-IL-2 could lead to an improved clinical outcome in patients with progressive RCC. MATERIALS AND METHODS: A total of 35 patients with progressive clear cell RCC received weekly infusions of WX-G250 for 11 weeks combined with a daily LD-IL-2 regimen. Patients were monitored longitudinally for ADCC capacity. Radiological assessment of metastatic lesions was performed at week 16 and regularly until disease progression. RESULTS: A durable clinical benefit was achieved in 8 of 35 patients (23%), including 3 with a partial response and 5 with stabilization at 24 weeks or greater. Mean survival was 22 months. In general treatment was well tolerated with little toxicity. The number of effector cells increased during treatment but lytic capacity per cell did not increase. ADCC and clinical outcome did not appear to correlate. CONCLUSIONS: WX-G250 combined with LD-IL-2 in patients with metastatic RCC is safe and well tolerated. With a substantial clinical benefit and a median survival of 22 months in patients with metastatic RCC who have progressive disease at study entry combination therapy showed increased overall survival compared to WX-G250 monotherapy. Survival was at least similar to that of currently used cytokine regimens but with a favorable toxicity profile.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Carcinoma de Células Renales/tratamiento farmacológico , Interleucina-2/administración & dosificación , Neoplasias Renales/tratamiento farmacológico , Adulto , Anciano , Carcinoma de Células Renales/patología , Progresión de la Enfermedad , Quimioterapia Combinada , Femenino , Humanos , Neoplasias Renales/patología , Masculino , Persona de Mediana Edad , Estudios Prospectivos
18.
Anaesth Intensive Care ; 32(3): 372-6, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15264733

RESUMEN

We studied the efficacy of a range of doses of dexamethasone for prevention of postoperative nausea and vomiting following strabismus repair in children in a hospital-based, prospective, double-blinded, randomized, placebo-controlled trial. Two hundred and ten children were randomized to receive either dexamethasone in one of four dosages: 50 microg/kg (Group 1), 100 microg/kg (Group 2), 200 microg/kg (Group 3) and 250 microg/kg (Group 4) or normal saline (Group 5) prior to corrective surgery for strabismus. Anaesthesia was standardized and included nitrous oxide, pethidine, intubation and the use of muscle relaxant and reversal with neostigmine. Postoperative nausea and vomiting were evaluated in epochs of 0-2 hours, 2-6 hours and 6-24 hours after surgery. Parent satisfaction was assessed 24 hours after surgery and the operated eye was examined for wound infection and delayed healing one week later Dexamethasone was effective in preventing nausea and vomiting after strabismus repair: 57.1% children in Group 1, 42.9% in Group 2, 52.4% in Group 3, and 59.5% in Group 4 were free from postoperative nausea and vomiting compared with 7.1% in placebo group. The lowest dose of 50 microg/kg was as efficacious as the higher dosages of dexamethasone during the 24 hours studied. Of the children who developed postoperative nausea and vomiting those who received dexamethasone had significantly fewer episodes than those in the placebo group. We conclude that dexamethasone 50 microg/kg is effective for the prevention of postoperative nausea and vomiting following strabismus repair in children.


Asunto(s)
Antieméticos/administración & dosificación , Dexametasona/administración & dosificación , Náusea y Vómito Posoperatorios/prevención & control , Estrabismo/cirugía , Adolescente , Antieméticos/efectos adversos , Niño , Preescolar , Dexametasona/efectos adversos , Método Doble Ciego , Femenino , Humanos , Masculino , Náusea y Vómito Posoperatorios/tratamiento farmacológico
19.
J Cell Sci ; 111 ( Pt 11): 1545-54, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9580562

RESUMEN

Here we present the cloning, expression and immunocytochemical localization of a novel 24 kDa protein, designated spinalin, which is present in the spines and operculum of Hydra nematocysts. Spinalin cDNA clones were identified by in situ hybridization to differentiating nematocytes. Sequencing of a full-length clone revealed the presence of an N-terminal signal peptide, suggesting that the mature protein is sorted via the endoplasmic reticulum to the post-Golgi vacuole in which the nematocyst is formed. The N-terminal region of spinalin (154 residues) is very rich in glycines (48 residues) and histidines (33 residues). A central region of 35 residues contains 19 glycines, occurring mainly as pairs. For both regions a polyglycine-like structure is likely and this may be stabilized by hydrogen bond-mediated chain association. Similar sequences found in loricrins, cytokeratins and avian keratins are postulated to participate in formation of supramolecular structures. Spinalin is terminated by a basic region (6 lysines out of 15 residues) and an acidic region (9 glutamates and 9 aspartates out of 32 residues). Western blot analysis with a polyclonal antibody generated against a recombinant 19 kDa fragment of spinalin showed that spinalin is localized in nematocysts. Following dissociation of the nematocyst's capsule wall with DTT, spinalin was found in the insoluble fraction containing spines and the operculum. Immunocytochemical analysis of developing nematocysts revealed that spinalin first appears in the matrix but then is transferred through the capsule wall at the end of morphogenesis to form spines on the external surface of the inverted tubule and the operculum.


Asunto(s)
Hydra/genética , Hydra/metabolismo , Proteínas/genética , Proteínas/aislamiento & purificación , Proteínas/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Glicina , Histidina , Inmunohistoquímica , Datos de Secuencia Molecular , Análisis de Secuencia
20.
Br J Cancer ; 90(5): 985-90, 2004 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-14997194

RESUMEN

Chimeric monoclonal antibody G250 (WX-G250) binds to a cell surface antigen found on >90% of renal cell carcinoma (RCC). A multicentre phase II study was performed to evaluate the safety and efficacy of WX-G250 in metastatic RCC (mRCC) patients. In all, 36 patients with mRCC were included. WX-G250 was given weekly by intravenous infusion for 12 weeks. Patients with stable disease (SD) or response were eligible to receive additional treatment for 8 weeks. None of the 36 enrolled patients experienced any drug-related grade III or IV toxicity. Only three patients had grade II toxicity possibly related to the study medication. In all, 10 patients had SD and received extended treatment. One complete response and a significant regression was observed during the follow-up of the treatment. Five patients with progressive disease at study entry were stable for more than 6 months after study entry. The median survival after treatment start was 15 months. The weekly schedule of WX-G250 was well tolerated. With a median survival of 15 months after the start of this treatment and two late clinical responses, WX-G250 seems to be able to modulate mRCC. To improve the activity of WX-G250-specific antibody-dependent cellular cytotoxicity and the clinical response rate, currently combinations of WX-G250 with cytokines are in phase II trials.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/uso terapéutico , Carcinoma de Células Renales/terapia , Neoplasias Renales/terapia , Proteínas Recombinantes de Fusión/uso terapéutico , Adulto , Anciano , Antígenos de Superficie/efectos de los fármacos , Antígenos de Superficie/inmunología , Carcinoma de Células Renales/inmunología , Carcinoma de Células Renales/secundario , Femenino , Humanos , Neoplasias Renales/inmunología , Neoplasias Renales/patología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
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