Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
1.
J Appl Clin Med Phys ; 16(5): 246­258, 2015 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-26699305

RESUMEN

The purpose of this study was to introduce a three-field monoisocentric inverse treatment planning method without half-beam blocks for breast cancer radiation treatments. Three-field monoisocentric breast treatment planning with half-beam blocks limits the tangential field length to 20 cm. A dual-isocenter approach accommodates patients with larger breasts, but prolongs treatment time and may introduce dose uncertainty at the matching plane due to daily setup variations. We developed a novel monoisocentric, three-field treatment planning method without half-beam blocking. The new beam-matching method utilizes the full field size with a single isocenter. Furthermore, an open/IMRT hybrid inverse optimization method was employed to improve dose uniformity and coverage. Geometric beam matching was achieved by rotating the couch, collimator, and gantry together. Formulae for three-field geometric matching were derived and implemented in Pinnacle scripts. This monoisocentric technique can be used for patients with larger breast size. The new method has no constraints on the length of tangential fields. Compared with the dual-isocenter method, it can significantly reduce patient setup time anduncertainties.


Asunto(s)
Neoplasias de la Mama/radioterapia , Fantasmas de Imagen , Planificación de la Radioterapia Asistida por Computador/métodos , Femenino , Humanos , Aceleradores de Partículas , Dosificación Radioterapéutica
2.
Int J Radiat Oncol Biol Phys ; 91(2): 435-43, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25636766

RESUMEN

PURPOSE: This study compared normal tissue complication probability (NTCP) modeling of chronic gastrointestinal toxicities following prostate cancer treatment for 2 treatment modalities. Possible factors causing discrepancies in optimal NTCP model parameters between 3-dimensional conformal radiation therapy (3D-CRT) and intensity modulated RT (IMRT) were analyzed and discussed, including the impact of patient characteristics, image guidance, toxicity scoring bias, and NTCP model limitations. METHODS AND MATERIALS: Rectal wall dose-volume histograms of 1115 patients treated for prostate cancer under an adaptive radiation therapy protocol were used to model gastrointestinal toxicity grade ≥2 (according to Common Terminology Criteria for Adverse Events). A total of 457 patients were treated with 3D-CRT and 658 with IMRT. 3D-CRT patients were matched to IMRT patients based on various patient characteristics, using a propensity score-based algorithm. Parameters of the Lyman equivalent uniform dose and cut-off dose logistic regression NTCP models were estimated for the 2 matched treatment modalities and the combined group. RESULTS: After they were matched, the 3D-CRT and IMRT groups contained 275 and 550 patients with a large discrepancy of 28.7% versus 7.8% toxicities, respectively (P<.001). For both NTCP models, optimal parameters found for the 3D-CRT groups did not fit the IMRT patients well and vice versa. Models developed for the combined data overestimated NTCP for the IMRT patients and underestimated NTCP for the 3D-CRT group. CONCLUSIONS: Our analysis did not reveal a single definitive cause for discrepancies of model parameters between 3D-CRT and IMRT. Patient characteristics and bias in toxicity scoring, as well as image guidance alone, are unlikely causes of the large discrepancy of toxicities. Whether the cause was inherent to the specific NTCP models used in this study needs to be verified by future investigations. Because IMRT is increasingly used clinically, it is important that appropriate NTCP model parameters are determined for this treatment modality.


Asunto(s)
Enfermedades Gastrointestinales/epidemiología , Modelos Biológicos , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/radioterapia , Traumatismos por Radiación/epidemiología , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Conformacional/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Causalidad , Comorbilidad , Simulación por Computador , Enfermedades Gastrointestinales/etiología , Alemania/epidemiología , Humanos , Incidencia , Masculino , Análisis por Apareamiento , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Traumatismos por Radiación/etiología , Radioterapia Conformacional/efectos adversos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Medición de Riesgo , Sensibilidad y Especificidad , Resultado del Tratamiento
3.
Int J Radiat Oncol Biol Phys ; 91(1): 124-32, 2015 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25442337

RESUMEN

PURPOSE: To compare toxicity after stereotactic body radiation therapy (SBRT) for "central" tumors-within 2 cm of the proximal bronchial tree or with planning tumor volume (PTV) touching mediastinum-versus noncentral ("peripheral") lung tumors. METHODS AND MATERIALS: From November 2005 to January 2011, 229 tumors (110 central, 119 peripheral; T1-3N0M0 non-small-cell lung cancer and limited lung metastases) in 196 consecutive patients followed prospectively at a single institution received moderate-dose SBRT (48-60 Gy in 4-5 fractions [biologic effective dose=100-132 Gy, α/ß=10]) using 4-dimensional planning, online image-guided radiation therapy, and institutional dose constraints. Clinical adverse events (AEs) were graded prospectively at clinical and radiographic follow-up using Common Terminology Criteria for Adverse Events version 3.0. Pulmonary function test (PFT) decline was graded as 2 (25%-49.9% decline), 3 (50.0%-74.9% decline), or 4 (≥75.0% decline). Central/peripheral location was assessed retrospectively on planning CT scans. Groups were compared after propensity score matching. Characteristics were compared with χ(2) and 2-tailed t tests, adverse events with χ(2) test-for-trend, and cumulative incidence using competing risks analysis (Gray's test). RESULTS: With 79 central and 79 peripheral tumors matched, no differences in AEs were observed after 17 months median follow-up. Two-year cumulative incidences of grade ≥2 pain, musculoskeletal, pulmonary, and skin AEs were 14%, 5%, 6%, and 10% (central) versus 19%, 10%, 10%, and 3% (peripheral), respectively (P=.31, .38, .70, and .09). Grade ≥2 cardiovascular, gastrointestinal, and central nervous system AEs were rare (<1%). Two-year incidences of grade ≥2 clinical AEs (28% vs 25%, P=.79), grade ≥2 PFT decline (36% vs 34%, P=.94), grade ≥3 clinical AEs (3% vs 7%, P=.48), and grade ≥3 PFT decline (0 vs 10%, P=.11) were similar for central versus peripheral tumors, respectively. Pooled 2-year incidences of grades 4 and 5 AEs were <1% and 0%, respectively, in both the prematched and matched groups. CONCLUSION: Moderate-dose SBRT with these techniques yields a similarly safe toxicity profile for both central and peripheral lung tumors.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/cirugía , Neoplasias Pulmonares/cirugía , Traumatismos por Radiación/epidemiología , Radiocirugia/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Carcinoma de Pulmón de Células no Pequeñas/patología , Distribución de Chi-Cuadrado , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Incidencia , Neoplasias Pulmonares/patología , Masculino , Mediastino/patología , Persona de Mediana Edad , Órganos en Riesgo/efectos de la radiación , Dolor/etiología , Puntaje de Propensión , Radiocirugia/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Guiada por Imagen/efectos adversos , Radioterapia Guiada por Imagen/métodos , Pruebas de Función Respiratoria , Factores Sexuales , Carga Tumoral , Adulto Joven
4.
Brachytherapy ; 13(1): 59-67, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-23871661

RESUMEN

PURPOSE: We compared outcomes in intermediate-risk prostate cancer patients treated with dose-escalated adaptive image-guided radiation therapy (IGRT) or dose-escalated high-dose-rate brachytherapy boost (HDR-B). METHODS AND MATERIALS: Patients with intermediate-risk prostate cancer by National Comprehensive Cancer Network criteria were treated with either CT-based off-line adaptive IGRT (n = 734) or HDR-B (n = 282). IGRT was delivered with 3D-conformal or intensity-modulated radiation therapy with a median dose of 77.4 Gy. For HDR-B, the whole pelvis received a median 46 Gy, and the prostate 2 implants of 9.5 Gy (n = 71), 10.5 Gy (n = 155), or 11.5 Gy (n = 56). RESULTS: Median followup was 3.7 years for IGRT and 8.0 years for HDR-B (p < 0.001). Eight-year biochemical control was 86% for IGRT and 91% for HDR-B (p = 0.22), disease-free survival 67% for IGRT and 79% for HDR-B (p = 0.006), and overall survival 75% for IGRT and 86% for HDR-B (p = 0.009). Cause-specific survival (8-year, 100% vs. 99%), freedom from distant metastases (98% vs. 97%), and freedom from local recurrence (98% vs. 98%) did not differ (p > 0.50 each). A worse prognosis group was defined by percent positive prostate biopsy cores >50%, perineural invasion, or stage T2b-c, encompassing 260 (35%) IGRT and 171 (61%) HDR-B patients. These patients evidenced a 5-year biochemical control of 96% for HDR-B and 87% for IGRT (p = 0.002). CONCLUSIONS: Dose-escalated IGRT and HDR-B both yield excellent clinical outcomes for patients with intermediate-risk prostate cancer. Improved biochemical control with HDR-B for patients with worse pretreatment characteristics suggests that a subgroup of intermediate-risk prostate cancer patients may benefit from dual-modality treatment.


Asunto(s)
Braquiterapia/métodos , Neoplasias de la Próstata/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Radioterapia Guiada por Imagen/métodos , Radioterapia de Intensidad Modulada/métodos
5.
Head Neck ; 36(8): 1155-61, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23852670

RESUMEN

BACKGROUND: We compared dependence rates, complications, toxicities, and costs associated with prophylactic versus reactive percutaneous endoscopic gastrostomy (PEG) tube placement. METHODS: One hundred ninety-three patients with locally advanced head and neck squamous cell carcinoma treated with concurrent chemoradiotherapy were retrospectively reviewed. RESULTS: The 1-year and 2-year actuarial PEG tube dependence rate of the entire cohort was 24% and 13%, respectively. There was no difference in the PEG tube dependence rates between those placed prophylactically versus reactively. Patients who received a PEG tube reactively had a significantly higher stricture rate (p = .03) and aspiration rate (p < .001) compared to the prophylactic group. There were significantly fewer hospitalizations in the prophylactic group compared to the reactive group (p = .003). When accounting for both PEG placement and hospitalizations, the prophylactic approach was found to be more cost effective. CONCLUSION: PEG tubes placed prophylactically were associated with lower rates of strictures, aspirations, hospitalizations, and costs compared to those placed reactively.


Asunto(s)
Carcinoma de Células Escamosas/terapia , Quimioradioterapia/métodos , Trastornos de Deglución/prevención & control , Nutrición Enteral/instrumentación , Gastrostomía/métodos , Neoplasias de Cabeza y Cuello/terapia , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/economía , Costos y Análisis de Costo , Trastornos de Deglución/economía , Endoscopía Gastrointestinal , Femenino , Gastrostomía/economía , Neoplasias de Cabeza y Cuello/economía , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello , Resultado del Tratamiento
6.
Brachytherapy ; 13(2): 163-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24295963

RESUMEN

PURPOSE: To compare erectile dysfunction (ED) after adaptive dose-escalated image-guided intensity-modulated radiotherapy (IG-IMRT) and high-dose-rate interstitial brachytherapy (HDR) monotherapy. METHODS AND MATERIALS: Low- and intermediate-risk prostate cancer patients treated with IG-IMRT or HDR were matched on pretreatment ED, age, Gleason score, T-stage, and prostate specific antigen. Patients who received androgen deprivation therapy were excluded. ED was graded by Common Terminology Criteria for Adverse Events v4. Actuarial rates of ED were computed by the Kaplan-Meier method. RESULTS: There were 384 patients with median followup of 2.0 years (0.5-6.1) for IG-IMRT and 2.0 years (0.5-8.7) for HDR. The median IG-IMRT dose was 75.6 Gy and HDR dose 38 Gy in four fractions. For patients with no pretreatment ED, actuarial rates of requiring intervention (Grade ≥2 ED) at 3 years were 31% for IG-IMRT and 19% for HDR (p=0.23), and impotence despite medical intervention (Grade 3) were 0% for IG-IMRT and 6% for HDR (p=0.06). For patients with Grade 1 pretreatment ED, Grade ≥2 ED at 3 years were 47% for IG-IMRT and 34% for HDR (p=0.79), and Grade 3 ED were 15% in both groups (p=0.59). For patients with Grade 2 pretreatment ED, Grade 3 ED at 3 years were 22% for IG-IMRT and 37% for HDR (p=0.70). No variables were predictive of Grade ≥2 ED following treatment. CONCLUSIONS: Rates of ED requiring medical intervention for both IG-IMRT and HDR are low and equivalent. Even patients with ED before treatment are likely to maintain potency with medication use at 3 years following treatment.


Asunto(s)
Braquiterapia/efectos adversos , Disfunción Eréctil/etiología , Neoplasias de la Próstata/radioterapia , Radioterapia de Intensidad Modulada/efectos adversos , Anciano , Braquiterapia/métodos , Estudios de Casos y Controles , Relación Dosis-Respuesta en la Radiación , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Antígeno Prostático Específico , Radioterapia Guiada por Imagen
7.
Med Phys ; 40(10): 101710, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24089900

RESUMEN

PURPOSE: To develop a real-time markerless 3D tumor tracking using kilovoltage (kV) cone-beam CT (CBCT) projection images during volumetric modulated arc therapy (VMAT) treatment of lung tumors. METHODS: The authors have developed a method to identify the position of lung tumors during VMAT treatment, where the current mean 3D position is detected and subsequently the real time 3D position is obtained. The mean position is evaluated by iteratively minimizing an observation error function between the tumor coordinate detected in the imaging plane and the coordinate of the corresponding projection of the estimated mean position. The 3D trajectory is reconstructed using the same optimization formalism, where an observation error function is minimized for tumor positions confined within a predefined amplitude bin as determined from the superior-inferior tumor motion. Dynamic phantom experiments were performed and image data acquired during patient treatment were analyzed to characterize the reconstruction ability of the proposed method. RESULTS: The proposed algorithm needs to acquire kV projection data until a certain gantry angle is passed through, termed the black-out angle, before accurate estimation mean 3D tumor position is possible. The black-out angle for the mean position method is approximately 20°, while for the 3D trajectory reconstruction an additional ≈ 15° is required. The mean 3D position and 3D trajectory reconstruction are accurate within ± 0.5 mm. CONCLUSIONS: The authors present a real-time tracking framework to locate lung tumors during VMAT treatment using an optimization algorithm applied to CBCT kV projection images taken concomitantly with the treatment delivery. The authors' technique does not introduce significant additional dose and can be used for real-time treatment monitoring.


Asunto(s)
Algoritmos , Imagenología Tridimensional/métodos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/radioterapia , Radioterapia de Intensidad Modulada/métodos , Tomografía Computarizada de Haz Cónico , Tomografía Computarizada Cuatridimensional , Humanos , Imagenología Tridimensional/instrumentación , Fantasmas de Imagen , Radioterapia de Intensidad Modulada/instrumentación , Factores de Tiempo
8.
J Neurosurg ; 115(2): 220-9, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21548745

RESUMEN

OBJECT: The object of this study was to determine the benefit of surgery, radiation, and chemotherapy for patients with glioblastoma multiforme (GBM) and a low Karnofsky Performance Scale (KPS) score. METHODS: The authors retrospectively evaluated the records of patients who underwent primary treatment for pathologically confirmed GBM and with a KPS score ≤ 50 on initial evaluation for radiation therapy at a tertiary care institution between 1977 and 2006. Seventy-four patients with a median age of 69 years (range 19-88 years) and a median KPS score of 50 (range 20-50) were retrospectively grouped into the Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis (RPA) Classes IV (11 patients), V (15 patients), and VI (48 patients). Patients underwent biopsy (38 patients) or tumor resection (36 patients). Forty-seven patients received radiation. Nineteen patients also received chemotherapy (53% temozolomide), initiated concurrently (47%) or after radiotherapy. RESULTS: The median survival overall was 2.3 months (range 0.2-48 months). Median survival stratified by RPA Classes IV, V, and VI was 6.6, 6.6, and 1.8 months, respectively (p < 0.001, log-rank test). Median survival for patients receiving radiation (5.2 months) was greater than that for patients who declined radiation (1.6 months, p < 0.001). Patients in RPA Class VI appeared to benefit from radiotherapy only when tumor resection was also performed. The median survival from treatment initiation was greater for patients receiving chemotherapy concomitantly with radiotherapy (9.8 months) as compared with radiotherapy alone (1.7 months, p = 0.002). Of 20 patients seen for follow-up in the clinic at a median of 48 days (range 24-196 days) following radiotherapy, 70% were noted to have an improvement in the KPS score of between 10 and 30 points from the baseline score. On multivariate analysis, only RPA class (p = 0.01), resection (HR = 0.37, p = 0.001), and radiation therapy (HR = 0.39, p = 0.02) were significant predictors of a decreased mortality rate. CONCLUSIONS: Patients with a KPS score ≤ 50 appear to have increased survival and functional status following tumor resection and radiation. The extent of benefit from concomitant chemotherapy is unclear. Future studies may benefit from reporting that utilizes a prognostic classification system such as the RTOG RPA class, which has been shown to be effective at separating outcomes even in patients with low performance status. Patients with GBMs and low KPS scores need to be evaluated in prospective studies to identify the extent to which different therapies improve outcomes.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/cirugía , Terapia Combinada , Femenino , Estudios de Seguimiento , Glioblastoma/tratamiento farmacológico , Glioblastoma/cirugía , Humanos , Estado de Ejecución de Karnofsky , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
9.
Methods Mol Biol ; 723: 239-54, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21370070

RESUMEN

Candidate interactions identified by high-throughput protein microarray screening require rigorous -confirmation. Such validation is time-consuming and labor-intensive using conventional techniques. We describe a medium-throughput validation protocol based on coprecipitation of biotin-labeled -proteins synthesized in vitro using a rabbit reticulocyte lysate-coupled transcription and translation system. As our experimental system is based on screening for serum antibodies, we also present methods on purifying immunoglobulin from serum and quantifying the amount of coprecipitated (immunoprecipitated) target protein on Western blot. This technique provides a sensitive confirmatory test allowing for the rapid elimination of false positives prior to more extensive validation and analysis of target interactions in their native environment.


Asunto(s)
Inmunoprecipitación/métodos , Análisis por Matrices de Proteínas/métodos , Mapeo de Interacción de Proteínas/métodos , Estudios de Validación como Asunto , Animales , Western Blotting , Electroforesis en Gel de Poliacrilamida , Humanos , Inmunoglobulina G/biosíntesis , Inmunoglobulina G/sangre , Inmunoglobulina G/aislamiento & purificación , Inmunoglobulina G/metabolismo , Linfocitos/metabolismo , Unión Proteica , Biosíntesis de Proteínas
10.
Methods Mol Biol ; 723: 337-47, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21370075

RESUMEN

Protein microarrays are a high-throughput technology capable of generating large quantities of proteomics data. They can be used for general research or for clinical diagnostics. Bioinformatics and statistical analysis techniques are required for interpretation and reaching biologically relevant conclusions from raw data. We describe essential algorithms for processing protein microarray data, including spot-finding on slide images, Z score, and significance analysis of microarrays (SAM) calculations, as well as the concentration dependent analysis (CDA). We also describe available tools for protein microarray analysis, and provide a template for a step-by-step approach to performing an analysis centered on the CDA method. We conclude with a discussion of fundamental and practical issues and considerations.


Asunto(s)
Interpretación Estadística de Datos , Análisis por Matrices de Proteínas/métodos , Algoritmos , Programas Informáticos
11.
Auton Neurosci ; 157(1-2): 81-90, 2010 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-20494627

RESUMEN

The study of the mechanism of acupuncture action was revolutionized by the use of functional magnetic resonance imaging (fMRI). Over the past decade, our fMRI studies of healthy subjects have contributed substantially to elucidating the central effect of acupuncture on the human brain. These studies have shown that acupuncture stimulation, when associated with sensations comprising deqi, evokes deactivation of a limbic-paralimbic-neocortical network, which encompasses the limbic system, as well as activation of somatosensory brain regions. These networks closely match the default mode network and the anti-correlated task-positive network described in the literature. We have also shown that the effect of acupuncture on the brain is integrated at multiple levels, down to the brainstem and cerebellum. Our studies support the hypothesis that the effect of acupuncture on the brain goes beyond the effect of attention on the default mode network or the somatosensory stimulation of acupuncture needling. The amygdala and hypothalamus, in particular, show decreased activation during acupuncture stimulation that is not commonly associated with default mode network activity. At the same time, our research shows that acupuncture stimulation needs to be done carefully, limiting stimulation when the resulting sensations are very strong or when sharp pain is elicited. When acupuncture induced sharp pain, our studies show that the deactivation was attenuated or reversed in direction. Our results suggest that acupuncture mobilizes the functionally anti-correlated networks of the brain to mediate its actions, and that the effect is dependent on the psychophysical response. In this work we also discuss multiple avenues of future research, including the role of neurotransmitters, the effect of different acupuncture techniques, and the potential clinical application of our research findings to disease states including chronic pain, major depression, schizophrenia, autism, and Alzheimer's disease.


Asunto(s)
Acupuntura , Mapeo Encefálico , Sistema Límbico/fisiología , Puntos de Acupuntura , Animales , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Sistema Límbico/irrigación sanguínea , Imagen por Resonancia Magnética/métodos , Vías Nerviosas/irrigación sanguínea , Vías Nerviosas/fisiología , Oxígeno/sangre , Factores de Tiempo
12.
J Vis Exp ; (38)2010 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-20379133

RESUMEN

Functional MRI is used to study the effects of acupuncture on the BOLD response and the functional connectivity of the human brain. Results demonstrate that acupuncture mobilizes a limbic-paralimbic-neocortical network and its anti-correlated sensorimotor/paralimbic network at multiple levels of the brain and that the hemodynamic response is influenced by the psychophysical response. Physiological monitoring may be performed to explore the peripheral response of the autonomic nerve function. This video describes the studies performed at LI4 (hegu), ST36 (zusanli) and LV3 (taichong), classical acupoints that are commonly used for modulatory and pain-reducing actions. Some issues that require attention in the applications of fMRI to acupuncture investigation are noted.


Asunto(s)
Terapia por Acupuntura , Encéfalo/fisiología , Imagen por Resonancia Magnética/métodos , Adulto , Humanos
13.
Cancer Res ; 70(4): 1344-55, 2010 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-20124481

RESUMEN

Patients with chronic lymphocytic leukemia (CLL) who relapse after allogeneic transplant may achieve durable remission following donor lymphocyte infusion (DLI), showing the potency of donor-derived immunity in eradicating tumors. We sought to elucidate the antigenic basis of the effective graft-versus-leukemia (GvL) responses associated with DLI for the treatment of CLL by analyzing the specificity of plasma antibody responses developing in two DLI-treated patients who achieved long-term remission without graft-versus-host disease. By probing high-density protein microarrays with patient plasma, we discovered 35 predominantly intracellular antigens that elicited high-titer antibody reactivity greater in post-DLI than in pre-DLI plasma. Three antigens-C6orf130, MDS032, and ZFYVE19-were identified by both patients. Along with additional candidate antigens DAPK3, SERBP1, and OGFOD1, these proteins showed higher transcript and protein expression in B cells and CLL cells compared with normal peripheral blood mononuclear cells. DAPK3 and the shared antigens do not represent minor histocompatibility antigens, as their sequences are identical in both donor and tumor. Although ZFYVE19, DAPK3, and OGFOD1 elicited minimal antibody reactivity in 12 normal subjects and 12 chemotherapy-treated CLL patients, 5 of 12 CLL patients with clinical GvL responses were serologically reactive to these antigens. Moreover, antibody reactivity against these antigens was temporally correlated with clinical disease regression. These B-cell antigens represent promising biomarkers of effective anti-CLL immunity.


Asunto(s)
Antígenos de Superficie/análisis , Linfocitos B/inmunología , Biomarcadores de Tumor/sangre , Inmunidad Innata/inmunología , Leucemia Linfocítica Crónica de Células B/inmunología , Leucemia Linfocítica Crónica de Células B/terapia , Antígenos de Superficie/sangre , Antígenos de Superficie/genética , Antígenos de Superficie/metabolismo , Linfocitos B/metabolismo , Linfocitos B/patología , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Trasplante de Médula Ósea/inmunología , Linaje de la Célula/inmunología , Femenino , Humanos , Inmunidad Innata/genética , Epítopos Inmunodominantes/análisis , Epítopos Inmunodominantes/sangre , Leucemia Linfocítica Crónica de Células B/sangre , Leucemia Linfocítica Crónica de Células B/diagnóstico , Masculino , Persona de Mediana Edad , Mutación/fisiología , Pronóstico , Análisis por Matrices de Proteínas , Resultado del Tratamiento
14.
Cancer Res ; 70(3): 906-15, 2010 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-20103624

RESUMEN

Curative effects of graft-versus-leukemia-based therapies such as donor lymphocyte infusion (DLI) for chronic myelogenous leukemia (CML) may result from immunologic ablation of self-renewing CML progenitor cells. Patients who achieved durable remissions after DLI developed a significant B-cell lymphocytosis after treatment, which did not occur in patients who were unresponsive to DLI. In this study, we identified antigen targets of this B-cell response by probing two immunoproteomic platforms with plasma immunoglobulins from seven CML patients with clinically apparent graft-versus-leukemia responses after DLI. In total, 62 antigens elicited greater reactivity from post-DLI versus pre-DLI plasma. Microarray analysis revealed that >70% of the antigens were expressed in CML CD34(+) cells, suggesting that expression in malignant progenitor cells is a feature common to antibody targets of DLI. We confirmed elevated expression of three target antigens (RAB38, TBCE, and DUSP12) in CML that together consistently elicited antibody responses in 18 of 21 of an additional cohort of CML patients with therapeutic responses, but not in normal donors and rarely in non-CML patients. In summary, immunologic targets of curative DLI responses include multiple antigens on CML progenitor cells, identifying them as potential immunogens for vaccination and/or monitoring of immunotherapeutics designed to eliminate myeloid leukemia stem cells.


Asunto(s)
Regulación Leucémica de la Expresión Génica , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Proteínas de Neoplasias/genética , Células Madre Neoplásicas/metabolismo , Adulto , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/inmunología , Antígenos de Neoplasias/metabolismo , Western Blotting , Fosfatasas de Especificidad Dual/genética , Fosfatasas de Especificidad Dual/inmunología , Femenino , Perfilación de la Expresión Génica , Biblioteca de Genes , Efecto Injerto vs Leucemia/inmunología , Humanos , Inmunidad Humoral/inmunología , Células K562 , Leucemia Mielógena Crónica BCR-ABL Positiva/inmunología , Leucemia Mielógena Crónica BCR-ABL Positiva/terapia , Transfusión de Linfocitos , Masculino , Persona de Mediana Edad , Chaperonas Moleculares/genética , Chaperonas Moleculares/inmunología , Proteínas de Neoplasias/inmunología , Proteínas de Neoplasias/metabolismo , Células Madre Neoplásicas/inmunología , Células Madre Neoplásicas/patología , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Análisis por Matrices de Proteínas/métodos , Resultado del Tratamiento , Adulto Joven , Proteínas de Unión al GTP rab/genética , Proteínas de Unión al GTP rab/inmunología
15.
Brain Res ; 1287: 84-103, 2009 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-19559684

RESUMEN

Previous work has shown that acupuncture stimulation evokes deactivation of a limbic-paralimbic-neocortical network (LPNN) as well as activation of somatosensory brain regions. This study explores the activity and functional connectivity of these regions during acupuncture vs. tactile stimulation and vs. acupuncture associated with inadvertent sharp pain. Acupuncture during 201 scans and tactile stimulation during 74 scans for comparison at acupoints LI4, ST36 and LV3 was monitored with fMRI and psychophysical response in 48 healthy subjects. Clusters of deactivated regions in the medial prefrontal, medial parietal and medial temporal lobes as well as activated regions in the sensorimotor and a few paralimbic structures can be identified during acupuncture by general linear model analysis and seed-based cross correlation analysis. Importantly, these clusters showed virtual identity with the default mode network and the anti-correlated task-positive network in response to stimulation. In addition, the amygdala and hypothalamus, structures not routinely reported in the default mode literature, were frequently involved in acupuncture. When acupuncture induced sharp pain, the deactivation was attenuated or became activated instead. Tactile stimulation induced greater activation of the somatosensory regions but less extensive deactivation of the LPNN. These results indicate that the deactivation of the LPNN during acupuncture cannot be completely explained by the demand of attention that is commonly proposed in the default mode literature. Our results suggest that acupuncture mobilizes the anti-correlated functional networks of the brain to mediate its actions, and that the effect is dependent on the psychophysical response.


Asunto(s)
Terapia por Acupuntura/métodos , Encéfalo/fisiología , Red Nerviosa/fisiología , Puntos de Acupuntura , Terapia por Acupuntura/efectos adversos , Estudios de Cohortes , Humanos , Imagen por Resonancia Magnética/métodos , Dimensión del Dolor/métodos , Factores de Tiempo , Tacto/fisiología
16.
J Proteome Res ; 7(5): 2059-68, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18393456

RESUMEN

Protein microarray technology is rapidly growing and has the potential to accelerate the discovery of targets of serum antibody responses in cancer, autoimmunity and infectious disease. Analytical tools for interpreting this high-throughput array data, however, are not well-established. We developed a concentration-dependent analysis (CDA) method which normalizes protein microarray data based on the concentration of spotted probes. We show that this analysis samples a data space that is complementary to other commonly employed analyses, and demonstrate experimental validation of 92% of hits identified by the intersection of CDA with other tools. These data support the use of CDA either as a preprocessing step for a more complete proteomic microarray data analysis or as a stand-alone analysis method.


Asunto(s)
Algoritmos , Perfilación de la Expresión Génica/métodos , Análisis por Matrices de Proteínas/métodos , Estadística como Asunto/métodos , Antígenos/análisis , Biología Computacional/métodos , Humanos , Leucemia Linfocítica Crónica de Células B/sangre , Leucemia Mielógena Crónica BCR-ABL Positiva/sangre , Reproducibilidad de los Resultados
17.
BMC Complement Altern Med ; 7: 33, 2007 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-17973984

RESUMEN

BACKGROUND: Acupuncture stimulation elicits deqi, a composite of unique sensations that is essential for clinical efficacy according to traditional Chinese medicine (TCM). There is lack of adequate experimental data to indicate what sensations comprise deqi, their prevalence and intensity, their relationship to acupoints, how they compare with conventional somatosensory or noxious response. The objective of this study is to provide scientific evidence on these issues and to characterize the nature of the deqi phenomenon in terms of the prevalence of sensations as well as the uniqueness of the sensations underlying the deqi experience. METHODS: Manual acupuncture was performed at LI4, ST36 and LV3 on the extremities in randomized order during fMRI in 42 acupuncture naïve healthy adult volunteers. Non-invasive tactile stimulation was delivered to the acupoints by gentle tapping with a von Frey monofilament prior to acupuncture to serve as a sensory control. At the end of each procedure, the subject was asked if each of the sensations listed in a questionnaire or any other sensations occurred during stimulation, and if present to rate its intensity on a numerical scale of 1-10. Statistical analysis including paired t-test, analysis of variance, Spearman's correlation and Fisher's exact test were performed to compare responses between acupuncture and sensory stimulation. RESULTS: The deqi response was elicited in 71% of the acupuncture procedures compared with 24% for tactile stimulation when thresholded at a minimum total score of 3 for all the sensations. The frequency and intensity of individual sensations were significantly higher in acupuncture. Among the sensations typically associated with deqi, aching, soreness and pressure were most common, followed by tingling, numbness, dull pain, heaviness, warmth, fullness and coolness. Sharp pain of brief duration that occurred in occasional subjects was regarded as inadvertent noxious stimulation. The most significant differences in the deqi sensations between acupuncture and tactile stimulation control were observed with aching, soreness, pressure and dull pain. Consistent with its prominent role in TCM, LI4 showed the most prominent response, the largest number of sensations as well as the most marked difference in the frequency and intensity of aching, soreness and dull pain between acupuncture and tactile stimulation control. Interestingly, the dull pain generally preceded or occurred in the absence of sharp pain in contrast to reports in the pain literature. An approach to summarize a sensation profile, called the deqi composite, is proposed and applied to explain differences in deqi among acupoints. CONCLUSION: The complex pattern of sensations in the deqi response suggests involvement of a wide spectrum of myelinated and unmyelinated nerve fibers, particularly the slower conducting fibers in the tendinomuscular layers. The study provides scientific data on the characteristics of the 'deqi' response in acupuncture and its association with distinct nerve fibers. The findings are clinically relevant and consistent with modern concepts in neurophysiology. They can provide a foundation for future studies on the deqi phenomenon.


Asunto(s)
Puntos de Acupuntura , Fibras Nerviosas Mielínicas/fisiología , Fibras Nerviosas Amielínicas/fisiología , Qi , Sensación/fisiología , Adulto , Femenino , Humanos , Masculino , Dimensión del Dolor/métodos , Umbral del Dolor/fisiología , Valores de Referencia
18.
Proteomics ; 7(6): 976-91, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17370257

RESUMEN

Proteomics offers the most direct approach to understand disease and its molecular biomarkers. Biomarkers denote the biological states of tissues, cells, or body fluids that are useful for disease detection and classification. Clinical proteomics is used for early disease detection, molecular diagnosis of disease, identification and formulation of therapies, and disease monitoring and prognostics. Bioinformatics tools are essential for converting raw proteomics data into knowledge and subsequently into useful applications. These tools are used for the collection, processing, analysis, and interpretation of the vast amounts of proteomics data. Management, analysis, and interpretation of large quantities of raw and processed data require a combination of various informatics technologies such as databases, sequence comparison, predictive models, and statistical tools. We have demonstrated the utility of bioinformatics in clinical proteomics through the analysis of the cancer antigen survivin and its suitability as a target for cancer immunotherapy.


Asunto(s)
Biología Computacional , Neoplasias , Proteoma , Programas Informáticos , Secuencia de Aminoácidos , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Humanos , Sistema Inmunológico/fisiología , Datos de Secuencia Molecular , Proteínas de Neoplasias/clasificación , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/clasificación , Neoplasias/diagnóstico , Neoplasias/fisiopatología , Neoplasias/terapia , Pronóstico , Proteómica
19.
Neuroimage ; 27(3): 479-96, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16046146

RESUMEN

Clinical and experimental data indicate that most acupuncture clinical results are mediated by the central nervous system, but the specific effects of acupuncture on the human brain remain unclear. Even less is known about its effects on the cerebellum. This fMRI study demonstrated that manual acupuncture at ST 36 (Stomach 36, Zusanli), a main acupoint on the leg, modulated neural activity at multiple levels of the cerebro-cerebellar and limbic systems. The pattern of hemodynamic response depended on the psychophysical response to needle manipulation. Acupuncture stimulation typically elicited a composite of sensations termed deqi that is related to clinical efficacy according to traditional Chinese medicine. The limbic and paralimbic structures of cortical and subcortical regions in the telencephalon, diencephalon, brainstem and cerebellum demonstrated a concerted attenuation of signal intensity when the subjects experienced deqi. When deqi was mixed with sharp pain, the hemodynamic response was mixed, showing a predominance of signal increases instead. Tactile stimulation as control also elicited a predominance of signal increase in a subset of these regions. The study provides preliminary evidence for an integrated response of the human cerebro-cerebellar and limbic systems to acupuncture stimulation at ST 36 that correlates with the psychophysical response.


Asunto(s)
Acupuntura , Cerebelo/fisiología , Corteza Cerebral/fisiología , Sistema Límbico/fisiología , Adulto , Cerebelo/irrigación sanguínea , Corteza Cerebral/irrigación sanguínea , Circulación Cerebrovascular/fisiología , Femenino , Hemodinámica/fisiología , Humanos , Sistema Límbico/irrigación sanguínea , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Oxígeno/sangre , Dolor/fisiopatología , Manejo del Dolor , Tacto/fisiología
20.
J Gen Intern Med ; 20(8): 710-4, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16050879

RESUMEN

CONTEXT: The reliance on physical examination as a diagnostic aid is in decline. OBJECTIVE: To determine whether an educational program can increase the use of physical examination by medical residents. DESIGN AND PARTICIPANTS: A series of educational workshops were provided to 47 second- and third-year medical residents at a large academic teaching hospital. MEASUREMENTS: Interns and students reported the frequency and depth of clinical examination performance on morning rounds by their residents before and up to six months after the workshops. Behavior before and after the workshops was compared using a mixed model. RESULTS: A total of 374 reports were returned (77% response). After adjusting for the type of service and observer, there was a statistically significant 23% increase (P=.02) in the performance of physical examination among residents who attended the course. Residents significantly increased the fraction of patients they examined on rounds (absolute increase 11%, P=.002) but did not increase the depth of their examination. The change was greatest on general medical teams, among whom the performance of physical examination had been least frequent. Teaching and feedback events on medicine teams by residents to their interns (2.8 and 1.1 events per 2 weeks, respectively) and medical students (5.9 and 2.8 events per 2 weeks, respectively) remained infrequent. CONCLUSIONS: A skills improvement program can significantly increase the frequency of physical examination, but teaching and feedback events remain sporadic and infrequent.


Asunto(s)
Medicina Interna/educación , Internado y Residencia , Examen Físico , Adulto , Boston , Hospitales de Enseñanza , Humanos , Examen Físico/estadística & datos numéricos , Pautas de la Práctica en Medicina
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...