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1.
Support Care Cancer ; 32(9): 627, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39222247

RESUMEN

PURPOSE: Clinical guidelines recommend early palliative care for patients with advanced lung cancer. In rural and underserved community oncology practices with limited resources, both primary palliative care from an oncologist and specialty palliative care are needed to address patients' palliative care needs. The aim of this study is to describe community oncology clinicians' primary palliative care practices and perspectives on integrating specialty palliative care into routine advanced lung cancer treatment in rural and underserved communities. METHODS: Participants were clinicians recruited from 15 predominantly rural community oncology practices in Kentucky. Participants completed a one-time survey regarding their primary palliative care practices and knowledge, barriers, and facilitators to integrating specialty palliative care into advanced-stage lung cancer treatment. RESULTS: Forty-seven clinicians (30% oncologists) participated. The majority (72.3%) of clinicians worked in a rural county. Over 70% reported routinely asking patients about symptom and physical function concerns, whereas less than half reported routinely asking about key prognostic concerns. Roughly 30% held at least one palliative care misconception (e.g., palliative care is for only those who are stopping cancer treatment). Clinician-reported barriers to specialty palliative care referrals included fear a referral would send the wrong message to patients (77%) and concern about burdening patients with appointments (53%). Notably, the most common clinician-reported facilitator was a patient asking for a referral (93.6%). CONCLUSION: Educational programs and outreach efforts are needed to inform community oncology clinicians about palliative care, empower patients to request referrals, and facilitate patients' palliative care needs assessment, documentation, and standardized referral templates.


Asunto(s)
Neoplasias Pulmonares , Oncología Médica , Cuidados Paliativos , Humanos , Cuidados Paliativos/métodos , Masculino , Femenino , Persona de Mediana Edad , Neoplasias Pulmonares/terapia , Oncología Médica/métodos , Oncología Médica/organización & administración , Kentucky , Actitud del Personal de Salud , Adulto , Encuestas y Cuestionarios , Pautas de la Práctica en Medicina/estadística & datos numéricos , Servicios de Salud Rural/organización & administración , Atención Primaria de Salud/organización & administración
2.
Support Care Cancer ; 31(3): 190, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36847880

RESUMEN

PURPOSE: Despite clinical guidelines, palliative care is underutilized during advanced stage lung cancer treatment. To inform interventions to increase its use, patient-level barriers and facilitators (i.e., determinants) need to be characterized, especially among patients living in rural areas or those receiving treatment outside academic medical centers. METHODS: Between 2020 and 2021, advanced stage lung cancer patients (n = 77; 62% rural; 58% receiving care in the community) completed a one-time survey assessing palliative care use and its determinants. Univariate and bivariate analyses described palliative care use and determinants and compared scores by patient demographic (e.g., rural vs. urban) and treatment setting (e.g., community vs. academic medical center) factors. RESULTS: Roughly half said they had never met with a palliative care doctor (49.4%) or nurse (58.4%) as part of cancer care. Only 18% said they knew what palliative care was and could explain it; 17% thought it was the same as hospice. After palliative care was distinguished from hospice, the most frequently cited reasons patients stated they would not seek palliative care were uncertainty about what it would offer (65%), concerns about insurance coverage (63%), difficulty attending multiple appointments (60%), and lack of discussion with an oncologist (59%). The most common reasons patients stated they would seek palliative care were a desire to control pain (62%), oncologist recommendation (58%), and coping support for family and friends (55%). CONCLUSION: Interventions should address knowledge and misconceptions, assess care needs, and facilitate communication between patients and oncologists about palliative care.


Asunto(s)
Enfermería de Cuidados Paliativos al Final de la Vida , Hospitales para Enfermos Terminales , Neoplasias Pulmonares , Humanos , Cuidados Paliativos , Neoplasias Pulmonares/terapia , Dolor
3.
Hepatology ; 76(6): 1778-1793, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35603482

RESUMEN

BACKGROUND AND AIMS: Insulin resistance and poor glycemic control are key drivers of the development of NAFLD and have recently been shown to be associated with fibrosis progression in NASH. However, the underlying mechanisms involving dysfunctional glucose metabolism and relationship with NAFLD/NASH progression remain poorly understood. We set out to determine whether protease-activated receptor 2 (PAR2), a sensor of extracellular inflammatory and coagulation proteases, links NAFLD and NASH with liver glucose metabolism. APPROACH AND RESULTS: Here, we demonstrate that hepatic expression of PAR2 increases in patients and mice with diabetes and NAFLD/NASH. Mechanistic studies using whole-body and liver-specific PAR2-knockout mice reveal that hepatic PAR2 plays an unexpected role in suppressing glucose internalization, glycogen storage, and insulin signaling through a bifurcating Gq -dependent mechanism. PAR2 activation downregulates the major glucose transporter of liver, GLUT2, through Gq -MAPK-FoxA3 and inhibits insulin-Akt signaling through Gq -calcium-CaMKK2 pathways. Therapeutic dosing with a liver-homing pepducin, PZ-235, blocked PAR2-Gq signaling and afforded significant improvements in glycemic indices and HbA1c levels in severely diabetic mice. CONCLUSIONS: This work provides evidence that PAR2 is a major regulator of liver glucose homeostasis and a potential target for the treatment of diabetes and NASH.


Asunto(s)
Diabetes Mellitus Experimental , Resistencia a la Insulina , Enfermedad del Hígado Graso no Alcohólico , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Receptor PAR-2/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Hígado/metabolismo , Insulina/metabolismo , Glucosa/metabolismo , Ratones Noqueados
4.
Mol Metab ; 29: 99-113, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31668396

RESUMEN

OBJECTIVE: Increases in hepatic and plasma cholesterol occur in patients with nonalcoholic fatty liver disease (NAFLD), although the reason for this is not well understood. We investigated whether Protease-Activated Receptor 2 (PAR2) plays a role in cholesterol and lipid homeostasis in NAFLD. METHODS: Human liver biopsies (n = 108) were quantified for PAR2 expression from NAFLD cases randomly selected and stratified by liver fibrosis stage, the primary predictor for clinical outcomes, while controlling for age, gender, and BMI between fibrosis groups. Demographic data and laboratory studies on plasma samples were obtained within 6 months of liver biopsy. Wild-type and PAR2-KO (C57BL/6 F2rl1-/-) mice were fed either normal or high fat diet for 16 weeks and plasma and liver assayed for lipids and soluble metabolites. RESULTS: Severity of NAFLD and plasma cholesterol levels significantly correlated with hepatocyte PAR2 expression in NAFLD patients. Conversely, PAR2 deficiency in mice resulted in reduced expression of key hepatic genes involved in cholesterol synthesis, a 50% drop in plasma and total liver cholesterol, and induced a reverse cholesterol transport system that culminated in 25% higher fecal bile acid output. PAR2-deficient mice exhibited enhanced fatty acid ß-oxidation with a ketogenic shift and an unexpected increase in liver glycogenesis. Mechanistic studies identified Gi-Jnk1/2 as key downstream effectors of protease-activated PAR2 in the regulation of lipid and cholesterol homeostasis in liver. CONCLUSIONS: These data indicate that PAR2 may be a new target for the suppression of plasma cholesterol and hepatic fat accumulation in NAFLD and related metabolic conditions.


Asunto(s)
Colesterol/metabolismo , Metabolismo de los Lípidos , Hígado/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Receptor PAR-2/metabolismo , Adulto , Anciano , Animales , Colesterol/sangre , Dieta Alta en Grasa , Progresión de la Enfermedad , Femenino , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/metabolismo , Humanos , Peroxidación de Lípido , Hígado/patología , Cirrosis Hepática/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Proteína Quinasa 8 Activada por Mitógenos/metabolismo , Proteína Quinasa 9 Activada por Mitógenos/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Receptor PAR-2/deficiencia , Receptor PAR-2/genética
5.
Am J Otolaryngol ; 40(5): 673-677, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31201038

RESUMEN

PURPOSE: Optimal treatment strategies for the management of oropharyngeal squamous cell carcinoma (OPSCC) remain unclear. The objective of this study is to examine the role of transoral robotic surgery (TORS) on functional and treatment outcomes. MATERIALS AND METHODS: A retrospective review of patients with OPSCC (tonsil/base of tongue) who underwent TORS with neck dissection± adjuvant therapy between January 2011 to December 2016 were compared to a stage matched cohort of patients treated with primary chemoradiation. Demographic, treatment, and outcome data were collected. RESULTS: 54 patients received primary chemoradiation and 65 patients (surgical group) received TORS ± adjuvant therapy for clinically staged disease meeting study criteria. 25% (N = 17) were treated with surgery alone. The remainder of the surgical group received postoperative radiation (N = 48), half of which received adjuvant chemotherapy (N = 24) in addition to radiation. 63% (N = 41) of the patients did not have risk factors for chemotherapy. No differences in overall or disease free survival were observed with TORS compared to chemoradiation (p = 0.9), although Charlson Comorbidity Index (CCI) was higher in the surgical group (p = 0.01). The strongest predictor of prolonged gastrostomy tube use was not treatment, but rather co-morbidity (p = 0.03), with no significant differences beyond 12 months. CONCLUSION: Although no significant survival differences were observed across treatment groups, this was maintained despite increased comorbidity index in the surgical patients. Given the ability to de-escalate and/or eliminate adjuvant therapy, particularly in a less healthy population, TORS would appear to be the viable treatment option it has become.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Quimioradioterapia/métodos , Cirugía Endoscópica por Orificios Naturales/métodos , Neoplasias Orofaríngeas/cirugía , Evaluación de Resultado en la Atención de Salud , Procedimientos Quirúrgicos Robotizados/métodos , Adulto , Anciano , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Estudios de Casos y Controles , Causas de Muerte , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Boca , Análisis Multivariante , Cirugía Endoscópica por Orificios Naturales/efectos adversos , Disección del Cuello/métodos , Invasividad Neoplásica/patología , Estadificación de Neoplasias , Neoplasias Orofaríngeas/tratamiento farmacológico , Neoplasias Orofaríngeas/mortalidad , Neoplasias Orofaríngeas/patología , Pronóstico , Radioterapia Adyuvante , Estudios Retrospectivos , Medición de Riesgo , Procedimientos Quirúrgicos Robotizados/efectos adversos , Análisis de Supervivencia , Resultado del Tratamiento
6.
J Radiosurg SBRT ; 5(3): 209-216, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29988318

RESUMEN

PURPOSE/OBJECTIVES: Since the inception of stereotactic body radiation therapy (SBRT), treatment delivery has been performed with volumetric modulated arc therapy (VMAT), helical tomotherapy (HT) and noncoplanar static fields (SF). The purpose of this study is to compare SBRT delivery among these treatment modalities to the lung. MATERIALS/METHODS: A retrospective review of SBRT treatments of 30 to 60 Gy in 1 to 5 fractions from 2007 to 2015 was performed. Dosimetric parameters included V5, V20, D2cm, gross tumor volume (GTV) and planning target volume (PTV) size and coverage, rib/esophageal minimum/maximum doses, R30Gy, R50%, and the conformality index (CI). Clinical outcomes evaluated included local control, pneumonitis and other toxicities. ANOVA, Student's t-test and Kruskal-Wallis test were used to compare the parameters among modalities. Kaplan-Meier estimates of time-to-local failure were produced. RESULTS: 176 Treatments included 106 SF, 36 VMAT and 34 HT. HT had better PTV coverage (p=0.0166) but higher lung V5 and esophageal doses (p<0.001 and p=0.0032). R30Gy, R50%, and CI were significantly better with VMAT SBRT (p<0.001). Clinically, Grade 2+ pneumonitis was associated with larger median GTV's of 21.39 cc versus 7.65 cc (p=0.0016), larger median PTV's of 65.62 cc versus 31.75 cc (p=0.0030), and higher V20 6.62% versus 4.08% (p=0.0408). For patients surviving >1 year, overall local failure rate was 9.4%. Actuarial control rates trended toward statistical significance with time to local failure with VMAT being the most favorable group on the Kaplan-Meier curve (p=0.0733). CONCLUSION: VMAT showed superior conformality compared to the other modalities. Among the modalities examined, HT had higher values for parameters associated with toxicity such as V5 and maximum esophageal dose, but all were within acceptable limits. There was a trend to better local control with VMAT.

7.
Arterioscler Thromb Vasc Biol ; 38(6): 1368-1380, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29622563

RESUMEN

OBJECTIVE: Protease-activated receptor-1 (PAR1) is classically activated by thrombin and is critical in controlling the balance of hemostasis and thrombosis. More recently, it has been shown that noncanonical activation of PAR1 by matrix metalloprotease-1 (MMP1) contributes to arterial thrombosis. However, the role of PAR1 in long-term development of atherosclerosis is unknown, regardless of the protease agonist. APPROACH AND RESULTS: We found that plasma MMP1 was significantly correlated (R=0.33; P=0.0015) with coronary atherosclerotic burden as determined by angiography in 91 patients with coronary artery disease and acute coronary syndrome undergoing cardiac catheterization or percutaneous coronary intervention. A cell-penetrating PAR1 pepducin, PZ-128, currently being tested as an antithrombotic agent in the acute setting in the TRIP-PCI study (Thrombin Receptor Inhibitory Pepducin-Percutaneous Coronary Intervention), caused a significant decrease in total atherosclerotic burden by 58% to 70% (P<0.05) and reduced plaque macrophage content by 54% (P<0.05) in apolipoprotein E-deficient mice. An MMP1 inhibitor gave similar beneficial effects, in contrast to the thrombin inhibitor bivalirudin that gave no improvement on atherosclerosis end points. Mechanistic studies revealed that inflammatory signaling mediated by MMP1-PAR1 plays a critical role in amplifying tumor necrosis factor α signaling in endothelial cells. CONCLUSIONS: These data suggest that targeting the MMP1-PAR1 system may be effective in tamping down chronic inflammatory signaling in plaques and halting the progression of atherosclerosis.


Asunto(s)
Enfermedades de la Aorta/enzimología , Aterosclerosis/enzimología , Enfermedades de las Arterias Carótidas/enzimología , Enfermedad de la Arteria Coronaria/enzimología , Metaloproteinasa 13 de la Matriz/metabolismo , Metaloproteinasa 1 de la Matriz/metabolismo , Receptor PAR-1/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Animales , Enfermedades de la Aorta/patología , Enfermedades de la Aorta/prevención & control , Aterosclerosis/patología , Aterosclerosis/prevención & control , Biomarcadores/sangre , Enfermedades de las Arterias Carótidas/patología , Enfermedades de las Arterias Carótidas/prevención & control , Línea Celular , Péptidos de Penetración Celular/farmacología , Ensayos Clínicos Fase II como Asunto , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/patología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Femenino , Fibrinolíticos/farmacología , Células Endoteliales de la Vena Umbilical Humana/enzimología , Humanos , Ácidos Hidroxámicos/farmacología , Lipopéptidos/farmacología , Masculino , Metaloproteinasa 1 de la Matriz/sangre , Inhibidores de la Metaloproteinasa de la Matriz/farmacología , Ratones Endogámicos C57BL , Ratones Noqueados para ApoE , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Oligopéptidos/farmacología , Placa Aterosclerótica , Ensayos Clínicos Controlados Aleatorios como Asunto , Receptor PAR-1/antagonistas & inhibidores , Receptor PAR-1/sangre , Transducción de Señal , Factor de Necrosis Tumoral alfa/sangre , Estados Unidos
8.
Int J Radiat Oncol Biol Phys ; 99(3): 652-659, 2017 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-29280459

RESUMEN

PURPOSE: To report long-term outcomes (risk of late toxicities, local control, and survival) of dose escalation by stereotactic radiation therapy boost to residual fluorodeoxyglucose positron emission tomography-positive residual disease after chemoradiation (CRT) in stage III non-small cell lung cancer (NSCLC). METHODS AND MATERIALS: Patients with stage IIB/III NSCLC underwent computed tomography or positron emission tomography-computed tomography screening approximately 1 month after completion of CRT. Limited residual disease (≤5 cm) within the site of the primary tumor received a stereotactic radiation therapy boost of either 10 Gy × 2 fractions or 6.5 Gy × 3 fractions to the primary tumor, to achieve a total Biologically Equivalent Dose >100 Gy. RESULTS: Thirty-seven patients received protocol therapy. With a median follow-up of 25.2 months, the crude local control rate for the entire group was 78% (n=29), but 10 patients (29%) and 24 patients (65%) developed regional and metastatic disease, respectively. At last follow-up, 5 patients (13.5%) remain alive, all with no evidence of disease, whereas 27 (73%) died of disease and the remaining 5 (13.5%) died of other causes. Median overall survival (OS) for the entire group was 25.2 months. Predictors for grade 3 pneumonitis included age and mean lung dose. Poorer median OS was associated with histology: median OS 15.6 months for squamous cell versus 34.8 months for other histologies (large cell neuroendocrine tumors excluded) (P=.04). The median progression-free survival was 6 months, with IIIB disease having significantly worse median progression-free survival (stages IIB/IIA being 9.4 months, vs 4.7 months for stage IIIB [P=.03]). CONCLUSIONS: Stereotactic radiation therapy boost after CRT is a safe treatment resulting in improvements in local control for locally advanced NSCLC. No additional late toxicities were seen. Possible improvement in OS was found, but further study in a larger prospective trial is needed.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Quimioradioterapia , Neoplasias Pulmonares/radioterapia , Radiocirugia/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/terapia , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/terapia , Masculino , Persona de Mediana Edad , Neoplasia Residual , Neumonía/etiología , Estudios Prospectivos , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
9.
Surg Neurol Int ; 8: 87, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28607821

RESUMEN

BACKGROUND: Frameless image-guided radiosurgery (IGRS) is a safe and effective noninvasive treatment for trigeminal neuralgia (TN). This study evaluates the use of frameless IGRS to treat patients with refractory TN. METHODS: We reviewed the records of 20 patients diagnosed with TN who underwent frameless IGRS treatments between March 2012 and December 2013. Facial pain was graded using the Barrow Neurological Institute (BNI) scoring system. The initial setup uncertainty from simulation to treatment and the patient intrafraction uncertainty were measured. The median follow-up was 32 months. RESULTS: All patients' pain was BNI Grade IV or V before the frameless IGRS treatment. The mean intrafraction shift was 0.43 mm (0.28-0.76 mm), and the maximum intrafraction shift was 0.95 mm (0.53-1.99 mm). At last follow-up, 8 (40%) patients no longer required medications (BNI 1 or 2), 11 (55%) patients were pain free but required medication (BNI 3), and 1 (5%) patient had no pain relief (BNI 5). Patients who did not have prior surgery had a higher odds ratio for pain relief compared to patients who had prior surgery (14.9, P = 0.0408). CONCLUSIONS: Frameless IGRS provides comparable dosimetric and clinical outcomes to frame-based SRS in a noninvasive fashion for patients with medically refractory TN.

10.
Radiat Oncol ; 10: 222, 2015 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-26520780

RESUMEN

BACKGROUND: Dexamethasone (DXM) is commonly used in the management of cerebral edema in patients diagnosed with glioblastoma multiforme (GBM). Bevacizumab (BEV) is FDA-approved for the progression or recurrence of GBM but has not been shown to improve survival when given for newly diagnosed patients concurrently with radiation (RT) and temozolomide (TMZ). Both DXM and BEV reduce cerebral edema, however, DXM has been shown to induce cytokine cascades which could interfere with cytotoxic therapy. We investigated whether DXM would reduce survival of GBM patients in the setting of concurrent TMZ and BEV administration. METHODS: We reviewed the treatment of all 73 patients with GBM who received definitive therapy at our institution from 2005 to 2013 with RT (60 Gy) delivered with concurrent daily TMZ (75 mg/m(2)). Of these, 34 patients also were treated with concurrent BEV (10 mg/kg every two weeks). Patients received adjuvant therapy (TMZ or TMZ/Bev) until either progression, discontinuation due to toxicity, or 12 months after radiation completion. All patients who had GBM progression with TMZ were offered BEV for salvage therapy, with 19 (56 %) receiving BEV. RESULTS: With a median follow-up of 15.6 months, 67 (91.8 %) patients were deceased. The OS for the entire cohort was 15.9 months, while the PFS was 7.7 months. The extent of resection was a prognostic indicator for OS (p = .0044). The median survival following gross tumor resection (GTR) was 22.5 months, subtotal resection (STR) was 14.9 months, and biopsy was 12.1 months. The addition of BEV to TMZ with RT was borderline significantly associated with increased PFS (9.4 vs. 5.1 months, p = 0.0574) although was not significantly associated with OS (18.1 vs. 15.3 months respectively, p = 0.3064). In patients receiving TMZ, DXM use concurrent with RT was a poor prognostic indicator of both OS (12.7 vs. 22.6 months, p = 0.003) and PFS (3.6 vs. 8.4 months, p <0.0001). DXM did not reduce OS in patients who received TMZ and BEV concurrently with RT (22.9 vs 22.8 months, p = 0.4818). On multivariable analysis, DXM use predicted an unfavorable OS hazard ratio (HR) = 1.72, p = 0.045). CONCLUSIONS: Our results with TMZ, BEV, and RT are similar to previous studies in terms of PFS and OS. DXM use during RT with concurrent TMZ correlated with reduced OS and PFS unless BEV was administered.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Dexametasona/administración & dosificación , Glioblastoma/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Bevacizumab/administración & dosificación , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/radioterapia , Quimioradioterapia/métodos , Dacarbazina/administración & dosificación , Dacarbazina/análogos & derivados , Dexametasona/efectos adversos , Supervivencia sin Enfermedad , Femenino , Glioblastoma/mortalidad , Glioblastoma/radioterapia , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Temozolomida
11.
Dev Biol ; 397(1): 31-44, 2015 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25236433

RESUMEN

Extraocular muscles (EOMs) are highly specialized skeletal muscles that originate from the head mesoderm and control eye movements. EOMs are uniquely spared in Duchenne muscular dystrophy and animal models of dystrophin deficiency. Specific traits of myogenic progenitors may be determinants of this preferential sparing, but very little is known about the myogenic cells in this muscle group. While satellite cells (SCs) have long been recognized as the main source of myogenic cells in adult muscle, most of the knowledge about these cells comes from the prototypic limb muscles. In this study, we show that EOMs, regardless of their distinctive Pax3-negative lineage origin, harbor SCs that share a common signature (Pax7(+), Ki67(-), Nestin-GFP(+), Myf5(nLacZ+), MyoD-positive lineage origin) with their limb and diaphragm somite-derived counterparts, but are remarkably endowed with a high proliferative potential as revealed in cell culture assays. Specifically, we demonstrate that in adult as well as in aging mice, EOM SCs possess a superior expansion capacity, contributing significantly more proliferating, differentiating and renewal progeny than their limb and diaphragm counterparts. These robust growth and renewal properties are maintained by EOM SCs isolated from dystrophin-null (mdx) mice, while SCs from muscles affected by dystrophin deficiency (i.e., limb and diaphragm) expand poorly in vitro. EOM SCs also retain higher performance in cell transplantation assays in which donor cells were engrafted into host mdx limb muscle. Collectively, our study provides a comprehensive picture of EOM myogenic progenitors, showing that while these cells share common hallmarks with the prototypic SCs in somite-derived muscles, they distinctively feature robust growth and renewal capacities that warrant the title of high performance myo-engines and promote consideration of their properties for developing new approaches in cell-based therapy to combat skeletal muscle wasting.


Asunto(s)
Distrofina/fisiología , Regulación del Desarrollo de la Expresión Génica , Músculo Esquelético/embriología , Regeneración/fisiología , Células Satélite del Músculo Esquelético/citología , Células Madre/citología , Animales , Linaje de la Célula , Proliferación Celular , Separación Celular , Trasplante de Células , Modelos Animales de Enfermedad , Distrofina/deficiencia , Extremidades/embriología , Femenino , Citometría de Flujo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos mdx , Ratones Transgénicos , Distrofia Muscular de Duchenne/genética
12.
Front Plant Sci ; 4: 181, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23802002

RESUMEN

Second generation feedstocks for bioethanol will likely include a sizable proportion of perennial C4 grasses, principally in the Panicoideae clade. The Panicoideae contain agronomically important annual grasses including Zea mays L. (maize), Sorghum bicolor (L.) Moench (sorghum), and Saccharum officinarum L. (sugar cane) as well as promising second generation perennial feedstocks including Miscanthus×giganteus and Panicum virgatum L. (switchgrass). The underlying complexity of these polyploid grass genomes is a major limitation for their direct manipulation and thus driving a need for rapidly cycling comparative model. Setaria viridis (green millet) is a rapid cycling C4 panicoid grass with a relatively small and sequenced diploid genome and abundant seed production. Stable, transient, and protoplast transformation technologies have also been developed for Setaria viridis making it a potentially excellent model for other C4 bioenergy grasses. Here, the lignocellulosic feedstock composition, cellulose biosynthesis inhibitor response and saccharification dynamics of Setaria viridis are compared with the annual sorghum and maize and the perennial switchgrass bioenergy crops as a baseline study into the applicability for translational research. A genome-wide systematic investigation of the cellulose synthase-A genes was performed identifying eight candidate sequences. Two developmental stages; (a) metabolically active young tissue and (b) metabolically plateaued (mature) material are examined to compare biomass performance metrics.

13.
Ann Neurol ; 65(6): 639-49, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19557869

RESUMEN

OBJECTIVE: Intrathecal IgG synthesis, persistence of bands of oligoclonal IgG, and memory B-cell clonal expansion are well-characterized features of the humoral response in multiple sclerosis (MS). Nevertheless, the target antigen of this response remains enigmatic. METHODS: We produced 53 different human IgG1 monoclonal recombinant antibodies (rAbs) by coexpressing paired heavy- and light-chain variable region sequences of 51 plasma cell clones and 2 B-lymphocyte clones from MS cerebrospinal fluid in human tissue culture cells. Chimeric control rAbs were generated from anti-myelin hybridomas in which murine variable region sequences were fused to human constant region sequences. Purified rAbs were exhaustively assayed for reactivity against myelin basic protein, proteolipid protein, and myelin oligodendrocyte glycoprotein by immunostaining of transfected cells expressing individual myelin proteins, by protein immunoblotting, and by immunostaining of human brain tissue sections. RESULTS: Whereas humanized control rAbs derived from anti-myelin hybridomas and anti-myelin monoclonal antibodies readily detected myelin antigens in multiple immunoassays, none of the rAbs derived from MS cerebrospinal fluid displayed immunoreactivity to the three myelin antigens tested. Immunocytochemical analysis of tissue sections from MS and control brain demonstrated only weak staining with a few rAbs against nuclei or cytoplasmic granules in neurons, glia, and inflammatory cells. INTERPRETATION: The oligoclonal B-cell response in MS cerebrospinal fluid is not targeted to the well-characterized myelin antigens myelin basic protein, proteolipid protein, or myelin oligodendrocyte glycoprotein.


Asunto(s)
Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/líquido cefalorraquídeo , Proliferación Celular , Inmunoglobulina G/biosíntesis , Inmunoglobulina G/líquido cefalorraquídeo , Esclerosis Múltiple/líquido cefalorraquídeo , Esclerosis Múltiple/inmunología , Células Plasmáticas/inmunología , Células Plasmáticas/patología , Animales , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Subgrupos de Linfocitos B/patología , Línea Celular , Células Clonales , Humanos , Ratones , Ratones Endogámicos BALB C , Esclerosis Múltiple/patología , Células Plasmáticas/metabolismo , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/líquido cefalorraquídeo
14.
J Appl Clin Med Phys ; 9(4): 57-67, 2008 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-19020487

RESUMEN

Electron-beam therapy is used to treat superficial tumors at a standard 100 cm source-to-surface distance (SSD). However, certain clinical situations require the use of an extended SSD. In the present study, Monte Carlo methods were used to investigate clinical electron beams, at standard and non-standard SSDs, from a Siemens Oncor Avant Garde (Siemens Healthcare, Erlangen, Germany) linear accelerator (LINAC). The LINAC treatment head was modeled in BEAMnrc for electron fields 5 cm in diameter and 10 x 10 cm, 15 x 15 cm, and 20 x 20 cm; for 6 MeV, 9 MeV, and 12 MeV; and for 100 cm, 110 cm, and 120 cm SSD. The DOSXYZnrc code was used to calculate extended SSD factors and dose contributions from various parts of the treatment head. The main effects of extended SSD on water phantom dose distributions were verified by Monte Carlo methods. Monte Carlo-calculated and measured extended SSD factors showed an average difference of +/-1.8%. For the field 5 cm in diameter, the relative output at extended SSD declined more rapidly than it did for the larger fields. An investigation of output contributions showed this decline was mainly a result of a rapid loss of scatter dose reaching the d max point from the lower scrapers of the electron applicator. The field 5 cm in diameter showed a reduction in dose contributions; the larger fields generally showed an increased contribution from the scrapers with increase in SSD. Angular distributions of applicator-scattered electrons have shown a large number of acute-angle electron tracks contributing to the output for larger field sizes, explaining the shallow output reduction.


Asunto(s)
Electrones , Aceleradores de Partículas/instrumentación , Radioterapia/instrumentación , Algoritmos , Diseño de Equipo , Humanos , Modelos Teóricos , Método de Montecarlo , Fantasmas de Imagen , Fotones , Radioterapia/métodos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Alta Energía , Dispersión de Radiación
15.
Clin Med Case Rep ; 1: 19-23, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-24179339

RESUMEN

Pathological rupture of the spleen in uncomplicated myeloma is extremely rare. We present a case of a splenic rupture which occurred in a 52 year old woman with uncomplicated multiple myeloma. The patient required an urgent splenectomy and had an uneventful recovery. Pathophysiological mechanisms leading to splenic rupture are discussed. Plasma cell leukaemias have been previously documented to present with splenic rupture. A subgroup of aggressive multiple myelomas such as in our case may have a similar tendency for splenic rupture.

16.
J Immunol Methods ; 326(1-2): 33-40, 2007 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-17669417

RESUMEN

Real-time immuno-PCR (RT-IPCR) is a powerful technique that combines ELISA with the specificity and sensitivity of PCR. RT-IPCR of phage-displayed peptides exploits the unique physical associations between phenotype (the displayed peptide) and genotype (the encoding DNA) within the same phage particle. Previously, we identified phage peptides specific for recombinant antibodies (rAbs) prepared from clonally expanded plasma cells in multiple sclerosis (MS) cerebrospinal fluid (CSF) and subacute sclerosing panencephalitis (SSPE) brain. Herein, we applied phage-mediated RT-IPCR to study reactivity of these specific phage peptides for the rAbs. Compared to standard ELISA, which required greater than 10(4) or 10(5) phage particles to detect binding to rAbs, RT-IPCR detected binding with as few as 100 phage particles. RT-IPCR was also superior to ELISA in determining relative affinities of rAbs for phage peptides and was effective in screening MS CSF for IgG reactivity to phage peptides. Phage-mediated RT-IPCR is a rapid, high-throughput technology that avoids the requirement for synthetic peptides and will facilitate the identification of candidate peptides that react with the IgG in MS CSF.


Asunto(s)
Autoanticuerpos/metabolismo , Bacteriófago M13/metabolismo , Péptidos/metabolismo , Reacción en Cadena de la Polimerasa , Mapeo de Interacción de Proteínas , Proteínas Recombinantes/metabolismo , Proteínas Virales/metabolismo , Autoanticuerpos/genética , Bacteriófago M13/inmunología , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoglobulina G/análisis , Inmunoglobulina G/líquido cefalorraquídeo , Esclerosis Múltiple/líquido cefalorraquídeo , Esclerosis Múltiple/inmunología , Péptidos/inmunología , Proteínas Recombinantes/genética , Proteínas Virales/inmunología
17.
J Virol ; 80(24): 12121-30, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17130301

RESUMEN

Infectious and inflammatory diseases of the CNS are often characterized by a robust B-cell response that manifests as increased intrathecal immunoglobulin G (IgG) synthesis and the presence of oligoclonal bands. We previously used laser capture microdissection and single-cell PCR to analyze the IgG variable regions of plasma cells from the brain of a patient with subacute sclerosing panencephalitis (SSPE). Five of eight human IgG1 recombinant antibodies (rAbs) derived from SSPE brain plasma cell clones recognized the measles virus (MV) nucleocapsid protein, confirming that the antibody response in SSPE targets primarily the agent causing disease. In this study, as part of our work on antigen identification, we used four rAbs to probe a random phage-displayed peptide library to determine if epitopes within the MV nucleocapsid protein could be identified with SSPE brain rAbs. All four of the SSPE rAbs enriched phage-displayed peptide sequences that reacted specifically to their panning rAb by enzyme-linked immunosorbent assay. BLASTP searches of the NCBI protein database revealed clear homologies in three peptides and different amino acid stretches within the 65 C-terminal amino acids of the MV nucleocapsid protein. The specificities of SSPE rAbs to these regions of the MV nucleocapsid protein were confirmed by binding to synthetic peptides or to short cDNA expression products. These results indicate the feasibility of using peptide screening for antigen discovery in central nervous system inflammatory diseases of unknown etiology, such as multiple sclerosis, neurosarcoidosis, or Behcet's syndrome.


Asunto(s)
Anticuerpos Antivirales/genética , Epítopos/genética , Virus del Sarampión/genética , Proteínas de la Nucleocápside/genética , Péptidos/genética , Panencefalitis Esclerosante Subaguda/inmunología , Secuencia de Aminoácidos , Biología Computacional , Ensayo de Inmunoadsorción Enzimática , Humanos , Datos de Secuencia Molecular , Biblioteca de Péptidos , Alineación de Secuencia , Análisis de Secuencia de ADN
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