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1.
Front Physiol ; 15: 1370079, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39100275

RESUMEN

There are several well-known medical conditions in which posture and gravity interact with natural history, including pregnancy. In this review, we provide a comprehensive overview of interactions between maternal posture and maternal physiology and pathophysiology at rest during pregnancy. We conducted a systematic literature search of the MEDLINE database and identified 644 studies from 1991 through 2021, inclusive, that met our inclusion criteria. We present a narrative review of the resulting literature and highlight discrepancies, research gaps, and potential clinical implications. We organize the results by organ system and, commencing with the neurological system, proceed in our synthesis generally in the craniocaudal direction, concluding with the skin. The circulatory system warranted our greatest and closest consideration-literature concerning the dynamic interplay between physiology (heart rate, stroke volume, cardiac output, blood pressure, and systemic vascular resistance), pathophysiology (e.g., hypertension in pregnancy), and postural changes provide an intricate and fascinating example of the importance of the subject of this review. Other organ systems discussed include respiratory, renal, genitourinary, gastrointestinal, abdominal, and endocrine. In addition to summarizing the existing literature on maternal posture-physiology interactions, we also point out gaps and opportunities for further research and clinical developments in this area. Overall, our review provides both insight into and relevance of maternal posture-physiology interactions vis à vis healthcare's mission to improve health and wellness during pregnancy and beyond.

2.
Front Physiol ; 15: 1394707, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38827993

RESUMEN

In numerous medical conditions, including pregnancy, gravity and posture interact to impact physiology and pathophysiology. Recent investigations, for example, pertaining to maternal sleeping posture during the third trimester and possible impact on fetal growth and stillbirth risk highlight the importance and potential clinical implications of the subject. In this review, we provide an extensive discussion of the impact of maternal posture on fetal physiology from conception to the postpartum period in human pregnancy. We conducted a systematic literature search of the MEDLINE database and identified 242 studies from 1991 through 2021, inclusive, that met our inclusion criteria. Herein, we provide a synthesis of the resulting literature. In the first section of the review, we group the results by the impact of maternal posture at rest on the cervix, uterus, placenta, umbilical cord, amniotic fluid, and fetus. In the second section of the review, we address the impact on fetal-related outcomes of maternal posture during various maternal activities (e.g., sleep, work, exercise), medical procedures (e.g., fertility, imaging, surgery), and labor and birth. We present the published literature, highlight gaps and discrepancies, and suggest future research opportunities and clinical practice changes. In sum, we anticipate that this review will shed light on the impact of maternal posture on fetal physiology in a manner that lends utility to researchers and clinicians who are working to improve maternal, fetal, and child health.

3.
Mol Imaging Biol ; 24(5): 830-841, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35482146

RESUMEN

PURPOSE: Bruton's tyrosine kinase (BTK) is a key component of B cell receptor (BCR) signaling, and as such a critical regulator of cell proliferation and survival. Aberrant BCR signaling is important in the pathogenesis of various B cell malignancies and autoimmune disorders. Here, we describe the development of a novel positron emission tomography (PET) tracer for imaging BTK expression and/or occupancy by small molecule therapeutics. METHODS: Radiochemistry was carried out by reacting the precursor with [18F]fluoride on a GE FX-FN TracerLab synthesis module to produce [18F]BTK-1 with a 6% decay-corrected radiochemical yield, 100 ± 6 GBq/µmol molar activity, and a radiochemical purity of 99%. Following intravenous administration of [18F]BTK-1 (3.63 ± 0.59 MBq, 0.084 ± 0.05 µg), 60-min dynamic images were acquired in two xenograft models: REC-1, an efficacious mantle cell lymphoma model, and U87MG, a non-efficacious glioblastoma model. Subsequent studies included vehicle, pretreatment (10 min prior to tracer injection), and displacement (30 min post-tracer injection) studies with different reversible BTK inhibitors to examine BTK binding. Human radiation dosimetry was estimated based on PET imaging in healthy rats. RESULTS: Uptake of [18F]BTK-1 was significantly higher in BTK expressing REC-1 tumors than non-BTK expressing U87MG tumors. Administration of BTK inhibitors prior to tracer administration blocked [18F]BTK-1 binding in the REC-1 tumor model consistent with [18F]BTK-1 binding to BTK. The predicted effective dose in humans was 0.0199 ± 0.0007 mSv/MBq. CONCLUSION: [18F]BTK-1 is a promising PET tracer for imaging of BTK, which could provide valuable information for patient selection, drug dose determination, and improving our understanding of BTK biology in humans.


Asunto(s)
Fluoruros , Inhibidores de Proteínas Quinasas , Humanos , Animales , Ratas , Adulto , Agammaglobulinemia Tirosina Quinasa/química , Agammaglobulinemia Tirosina Quinasa/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Receptores de Antígenos de Linfocitos B , Tomografía de Emisión de Positrones
4.
J Cardiovasc Transl Res ; 15(5): 927-943, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35288821

RESUMEN

Successful translation of new and innovative medical products from concept to clinical use is a complex endeavor that requires understanding and overcoming a variety of challenges. In particular, regulatory pathways and processes are often unfamiliar to academic researchers and start-ups, and even larger companies. Growing evidence suggests that the successful translation of ideas to products requires collaboration and cooperation between clinicians, researchers, industry, and regulators. A multi-stakeholder group developed this review to enhance regulatory knowledge and thereby improve translational success for medical devices. Communication between and among stakeholders is identified as a critical factor. Current regulatory programs and processes to facilitate communication and translation of innovative devices are described and discussed. Case studies are used to highlight the importance of flexibility when considering evidence requirements. We provide a review of emerging strategies, opportunities, and best practices to increase the regulatory knowledge base and facilitate medical device translation by all stakeholders. Clinicians, regulators, industry, and researchers require regulatory knowledge and collaboration for successful translation of innovative medical devices.


Asunto(s)
Comunicación
5.
Artículo en Inglés | MEDLINE | ID: mdl-32110775

RESUMEN

Preeclampsia leads to increased risk of morbidity and mortality for both mother and fetus. Most previous studies have largely neglected mechanical compression of the left renal vein by the gravid uterus as a potential mechanism. In this study, we first used a murine model to investigate the pathophysiology of left renal vein constriction. The results indicate that prolonged renal vein stenosis after 14 days can cause renal necrosis and an increase in blood pressure (BP) of roughly 30 mmHg. The second part of this study aimed to automate a diagnostic tool, known as the supine pressor test (SPT), to enable pregnant women to assess their preeclampsia development risk. A positive SPT has been previously defined as an increase of at least 20 mmHg in diastolic BP when switching between left lateral recumbent and supine positions. The results from this study established a baseline BP increase between the two body positions in nonpregnant women and demonstrated the feasibility of an autonomous SPT in pregnant women. Our results demonstrate that there is a baseline increase in BP of roughly 10-14 mmHg and that pregnant women can autonomously perform the SPT. Overall, this work in both rodents and humans suggests that (1) stenosis of the left renal vein in mice leads to elevation in BP and acute renal failure, (2) nonpregnant women experience a baseline increase in BP when they shift from left lateral recumbent to supine position, and (3) the SPT can be automated and used autonomously.

6.
Mol Cancer Ther ; 17(4): 795-805, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29483208

RESUMEN

Depatuxizumab mafodotin (depatux-m, ABT-414) is a tumor-selective antibody drug conjugate (ADC) comprised of the anti-EGFR antibody ABT-806 and the monomethyl auristatin F (MMAF) warhead. Depatux-m has demonstrated promising clinical activity in glioblastoma multiforme (GBM) patients and is currently being evaluated in clinical trials in first-line and recurrent GBM disease settings. Depatux-m responses have been restricted to patients with amplified EGFR, highlighting the need for therapies with activity against tumors with nonamplified EGFR overexpression. In addition, depatux-m dosing has been limited by corneal side effects common to MMAF conjugates. We hypothesized that a monomethyl auristatin E (MMAE) ADC utilizing an EGFR-targeting antibody with increased affinity may have broader utility against tumors with more modest EGFR overexpression while mitigating the risk of corneal side effects. We describe here preclinical characterization of ABBV-221, an EGFR-targeting ADC comprised of an affinity-matured ABT-806 conjugated to MMAE. ABBV-221 binds to a similar EGFR epitope as depatux-m and retains tumor selectivity with increased binding to EGFR-positive tumor cells and greater in vitro potency. ABBV-221 displays increased tumor uptake and antitumor activity against wild-type EGFR-positive xenografts with a greatly reduced incidence of corneal side effects relative to depatux-m. ABBV-221 has similar activity as depatux-m against an EGFR-amplified GBM patient derived xenograft (PDX) model and is highly effective alone and in combination with standard-of-care temozolomide in an EGFRvIII-positive GBM xenograft model. Based on these results, ABBV-221 has advanced to a phase I clinical trial in patients with advanced solid tumors associated with elevated levels of EGFR. Mol Cancer Ther; 17(4); 795-805. ©2018 AACR.


Asunto(s)
Anticuerpos Monoclonales Humanizados/farmacología , Glioblastoma/tratamiento farmacológico , Inmunoconjugados/farmacología , Oligopéptidos/química , Animales , Anticuerpos Monoclonales Humanizados/química , Apoptosis , Proliferación Celular , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/inmunología , Femenino , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos , Inmunoconjugados/química , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
7.
J Am Soc Hypertens ; 10(11): 891-899, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27751879

RESUMEN

The morbidity and mortality associated with preeclampsia is staggering. The physiology of the Page kidney, a condition in which increased intrarenal pressure causes hypertension, appears to provide a unifying framework to explain the complex pathophysiology. Page kidney hypertension is renin-mediated acutely and ischemia-mediated chronically. Renal venous outflow obstruction also causes a Page kidney phenomenon, providing a hypothesis for the increased vulnerability of a subset of women who have what we are hypothesizing is a "renal compartment syndrome" due to inadequate ipsilateral collateral renal venous circulation consistent with well-known variation in normal venous anatomy. Dynamic changes in renal venous anatomy and physiology in pregnancy appear to correlate with disease onset, severity, and recurrence. Since maternal recumbent position is well known to affect renal perfusion and since chronic outflow obstruction makes women vulnerable to the ischemic/inflammatory sequelae, heightened awareness of renal compartment syndrome physiology is critical. The anatomic and physiologic insights provide immediate strategies to predict and prevent preeclampsia with straightforward, low-cost interventions that make renewed global advocacy for pregnant women a realistic goal.


Asunto(s)
Síndromes Compartimentales/fisiopatología , Riñón/fisiopatología , Preeclampsia/fisiopatología , Circulación Renal , Venas Renales/anatomía & histología , Renina/metabolismo , Variación Anatómica , Circulación Colateral , Endotelina-1/sangre , Endotelina-1/metabolismo , Femenino , Humanos , Isquemia/fisiopatología , Riñón/irrigación sanguínea , Riñón/patología , Obesidad/complicaciones , Obesidad/fisiopatología , Preeclampsia/prevención & control , Embarazo , Venas Renales/fisiopatología , Sistema Renina-Angiotensina , Factores de Riesgo , Sistema Nervioso Simpático/fisiopatología
8.
Open Heart ; 3(2): e000411, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27493761

RESUMEN

OBJECTIVE: Functional (or secondary) mitral regurgitation (FMR) is associated with greater morbidity and worse outcomes in patients with congestive heart failure (CHF) and cardiomyopathy. The Carillon® Mitral Contour System® is a coronary sinus-based percutaneous therapy to reduce FMR. We evaluated the safety and efficacy of a modified version of the Carillon device in the treatment of patients with cardiomyopathy and FMR. METHODS: 36 patients with CHF, depressed left ventricular function (ejection fraction <40%) and at least moderate FMR underwent the Carillon device implant. RESULTS: There was 1 major adverse event within 30 days-a death (not device related)-occurring 17 days after the implant. Reductions in FMR and improvements in functional class and 6 min walk tests were seen, similar to prior studies. Device fractures in the high strain region of the proximal anchor (seen in prior studies) were not seen in this study. CONCLUSIONS: The modified Carillon device was associated with improvements in clinical and echocardiographic parameters in treating patients with FMR, while successfully addressing the issue of anchor fracture. This version of the Carillon device will be used in a blinded randomised trial of symptomatic patients with FMR.

9.
Mol Imaging Biol ; 18(3): 377-85, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26493052

RESUMEN

PURPOSE: Zr-89 positron emission tomography (PET) is a valuable tool for understanding the biodistribution and pharmacokinetics of antibody-based therapeutics. We compared the image quality of Zr-89 PET and F-18 PET in the Siemens microPET Focus 220 preclinical scanner using different reconstruction methods. PROCEDURES: Image quality metrics were measured in various Zr-89 and F-18 PET phantoms, including the NEMA NU 4-2008 image quality phantom. Images were reconstructed using various algorithms. RESULTS: Zr-89 PET had greater image noise, inferior spatial resolution, and greater spillover than F-18 PET, but comparable recovery coefficients for cylinders of various diameters. Of the reconstruction methods, OSEM3D resulted in the lowest noise, highest recovery coefficients, best spatial resolution, but also the greatest spillover. Scatter correction results were found to be sensitive to varying object sizes. CONCLUSIONS: Zr-89 PET image quality was inferior to that of F-18, and no single reconstruction method was superior in all aspects of image quality.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/normas , Tomografía de Emisión de Positrones/instrumentación , Tomografía de Emisión de Positrones/normas , Circonio/química , Algoritmos , Animales , Femenino , Macaca fascicularis , Fantasmas de Imagen , Radioisótopos
10.
BMC Cardiovasc Disord ; 15: 43, 2015 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-25971307

RESUMEN

BACKGROUND: To determine the cost-effectiveness of the percutaneous mitral valve repair (PMVR) using Carillon® Mitral Contour System® (Cardiac Dimensions Inc., Kirkland, WA, USA) in patients with congestive heart failure accompanied by moderate to severe functional mitral regurgitation (FMR) compared to the prolongation of optimal medical treatment (OMT). METHODS: Cost-utility analysis using a combination of a decision tree and Markov process was performed. The clinical effectiveness was determined based on the results of the Transcatheter Implantation of Carillon Mitral Annuloplasty Device (TITAN) trial. The mean age of the target population was 62 years, 77% of the patients were males, 64% of the patients had severe FMR and all patients had New York Heart Association functional class III. The epidemiological, cost and utility data were derived from the literature. The analysis was performed from the German statutory health insurance perspective over 10-year time horizon. RESULTS: Over 10 years, the total cost was €36,785 in the PMVR arm and €18,944 in the OMT arm. However, PMVR provided additional benefits to patients with an 1.15 incremental quality-adjusted life years (QALY) and an 1.41 incremental life years. The percutaneous procedure was cost-effective in comparison to OMT with an incremental cost-effectiveness ratio of €15,533/QALY. Results were robust in the deterministic sensitivity analysis. In the probabilistic sensitivity analysis with a willingness-to-pay threshold of €35,000/QALY, PMVR had a 84 % probability of being cost-effective. CONCLUSIONS: Percutaneous mitral valve repair may be cost-effective in inoperable patients with FMR due to heart failure.


Asunto(s)
Implantación de Prótesis de Válvulas Cardíacas/economía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Anuloplastia de la Válvula Mitral/economía , Anuloplastia de la Válvula Mitral/métodos , Insuficiencia de la Válvula Mitral/cirugía , Análisis Costo-Beneficio , Árboles de Decisión , Femenino , Alemania , Insuficiencia Cardíaca/complicaciones , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Humanos , Masculino , Cadenas de Markov , Persona de Mediana Edad , Insuficiencia de la Válvula Mitral/complicaciones , Insuficiencia de la Válvula Mitral/fisiopatología , Años de Vida Ajustados por Calidad de Vida , Sensibilidad y Especificidad
11.
J Pharmacol Exp Ther ; 343(3): 617-27, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22935731

RESUMEN

ABT-348 [1-(4-(4-amino-7-(1-(2-hydroxyethyl)-1H-pyrazol-4-yl)thieno[3,2-c]pyridin-3-yl)phenyl)-3-(3-fluorophenyl)urea] is a novel ATP-competitive multitargeted kinase inhibitor with nanomolar potency (IC(50)) for inhibiting binding and cellular autophosphorylation of Aurora B (7 and 13 nM), C (1 and 13 nM), and A (120 and 189 nM). Cellular activity against Aurora B is reflected by inhibition of phosphorylation of histone H3, induction of polyploidy, and inhibition of proliferation of a variety of leukemia, lymphoma, and solid tumor cell lines (IC(50) = 0.3-21 nM). In vivo inhibition of Aurora B was confirmed in an engrafted leukemia model by observing a decrease in phosphorylation of histone H3 that persisted in a dose-dependent manner for 8 h and correlated with plasma concentration of ABT-348. Evaluation of ABT-348 across a panel of 128 kinases revealed additional potent binding activity (K(i) < 30 nM) against vascular endothelial growth factor receptor (VEGFR)/platelet-derived growth factor receptor (PDGFR) families and the Src family of cytoplasmic tyrosine kinases. VEGFR/PDGFR binding activity correlated with inhibition of autophosphorylation in cells and inhibition of vascular endothelial growth factor (VEGF)-stimulated endothelial cell proliferation (IC(50) ≤ 0.3 nM). Evidence of on-target activity in vivo was provided by the potency for blocking VEGF-mediated vascular permeability and inducing plasma placental growth factor. Activity against the Src kinase family was evident in antiproliferative activity against BCR-ABL chronic myeloid leukemia cells and cells expressing the gleevec-resistant BCR-ABL T315I mutation. On the basis of its unique spectrum of activity, ABT-348 was evaluated and found effective in representative solid tumor [HT1080 and pancreatic carcinoma (MiaPaCa), tumor stasis] and hematological malignancy (RS4;11, regression) xenografts. These results provide the rationale for clinical assessment of ABT-348 as a therapeutic agent in the treatment of cancer.


Asunto(s)
Aminopiridinas/farmacología , Antineoplásicos/farmacología , Compuestos de Fenilurea/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Receptores del Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Receptores de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Familia-src Quinasas/antagonistas & inhibidores , Aminopiridinas/química , Aminopiridinas/farmacocinética , Aminopiridinas/uso terapéutico , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapéutico , Aurora Quinasa B , Aurora Quinasas , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Femenino , Histonas/antagonistas & inhibidores , Células Endoteliales de la Vena Umbilical Humana , Humanos , Leucemia Experimental/tratamiento farmacológico , Leucemia Experimental/enzimología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones SCID , Estructura Molecular , Células 3T3 NIH , Compuestos de Fenilurea/química , Compuestos de Fenilurea/farmacocinética , Compuestos de Fenilurea/uso terapéutico , Factores de Tiempo , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Bioorg Med Chem Lett ; 22(14): 4750-5, 2012 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-22695126

RESUMEN

In an effort to identify kinase inhibitors with dual KDR/Aurora B activity and improved aqueous solubility compared to the Abbott dual inhibitor ABT-348, a series of novel pyrazole pyrimidines structurally related to kinase inhibitor AS703569 were prepared. SAR work provided analogs with significant cellular activity, measureable aqueous solubility and moderate antitumor activity in a mouse tumor model after weekly ip dosing. Unfortunately these compounds were pan-kinase inhibitors that suffered from narrow therapeutic indices which prohibited their use as antitumor agents.


Asunto(s)
Inhibidores de Proteínas Quinasas/química , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Pirazoles/química , Pirimidinas/química , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Aminación , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Aurora Quinasa B , Aurora Quinasas , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Ratones , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/enzimología , Modelos Moleculares , Estructura Molecular , Pirimidinas/farmacología , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Eur J Heart Fail ; 14(8): 931-8, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22613584

RESUMEN

AIMS: Functional mitral regurgitation (FMR) contributes to morbidity and mortality in heart failure (HF) patients. The aim of this study was to determine whether percutaneous mitral annuloplasty could safely and effectively reduce FMR and yield durable long-term clinical benefit. METHODS AND RESULTS: The impact of mitral annuloplasty (Carillon Mitral Contour System) was evaluated in HF patients with at least moderate FMR. Patients in whom the device was placed then acutely recaptured for clinical reasons served as a comparator group. Quantitative measures of FMR, left ventricular (LV) dimensions, New York Heart Association (NYHA) class, 6 min walk distance (6MWD), and quality of life were assessed in both groups up to 12 months. Safety and key functional data were assessed in the implanted cohort up to 24 months. Thirty-six patients received a permanent implant; 17 had the device recaptured. The 30-day major adverse event rate was 1.9%. In contrast to the comparison group, the implanted cohort demonstrated significant reductions in FMR as represented by regurgitant volume [baseline 34.5 ±11.5 mL to 17.4 ±12.4 mL at 12 months (P < 0.001)]. There was a corresponding reduction in LV diastolic volume [baseline 208.5 ±62.0 mL to 178.9 ±48.0 mL at 12 months (P =0.015)] and systolic volume [baseline 151.8 ±57.1 mL to 120.7 ±43.2 mL at 12 months (P =0.015)], compared with progressive LV dilation in the comparator. The 6MWD markedly improved for the implanted patients by 102.5 ±164 m at 12 months (P =0.014) and 131.9 ±80 m at 24 months (P < 0.001). CONCLUSION: Percutaneous reduction of FMR using a coronary sinus approach is associated with reverse LV remodelling. Significant clinical improvements persisted up to 24 months.


Asunto(s)
Insuficiencia Cardíaca/cirugía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Anuloplastia de la Válvula Mitral/métodos , Insuficiencia de la Válvula Mitral/cirugía , Análisis de Varianza , Prueba de Esfuerzo , Tolerancia al Ejercicio , Femenino , Indicadores de Salud , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/patología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Calidad de Vida/psicología , Factores de Riesgo , Volumen Sistólico , Factores de Tiempo , Ultrasonografía , Función Ventricular Izquierda
14.
Cancer Chemother Pharmacol ; 69(6): 1669-72, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22327787

RESUMEN

Linifanib (ABT-869) is a multitargeted receptor tyrosine kinase inhibitor. This work aims to evaluate F-fluorodeoxyglucose-positron emission tomography (FDG-PET) as a pharmacodynamic (PD) biomarker for linifanib treatment utilizing the Calu-6 model of human non-small cell lung (NSCLC) cancer in SCID-beige mice. Animals received either vehicle or 12.5 mg/kg linifanib orally twice a day for the duration of the study. Imaging was performed at -1, 1, 3, and 7 days after beginning treatment (n = 12-14 per group). Linifanib inhibited tumor growth and suppressed tumor metabolic activity. Changes in tumor FDG uptake were observed as early as 1 day after beginning linifanib treatment and were sustained for the duration of the study. This study confirms that linifanib is efficacious in this xenograft model of human NSCLC and confirms FDG-PET is a potential PD biomarker strategy for linifanib therapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Fluorodesoxiglucosa F18 , Indazoles/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Compuestos de Fenilurea/uso terapéutico , Tomografía de Emisión de Positrones , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Animales , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Línea Celular Tumoral , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Ratones , Ratones SCID , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Mol Imaging Biol ; 14(5): 617-24, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22167582

RESUMEN

PURPOSE: Longitudinal changes of 3'-[(18) F]fluoro-3'-deoxythymidine (FLT) and 2-deoxy-2-[(18) F]fluoro-D-glucose (FDG) in response to irinotecan therapy in an animal model of colorectal cancer were compared. PROCEDURES: SCID/CB-17 mice with HCT116 tumors were treated with 50 mg/kg irinotecan by intraperitoneal injection weekly for 3 weeks. FLT and FDG-positron emission tomography (PET) were performed at baseline, the day after each treatment, and 5 days after the first treatment. Proliferation and apoptosis were evaluated by immunohistochemistry (IHC) after day 15 of imaging. RESULTS: Irinotecan treatment resulted in a suppression of tumor growth. Tumor FLT uptake was decreased the day after each treatment but to a lesser extent 5 days after the first treatment. FDG uptake increased the day after each treatment with a continuous increase throughout the experiment. IHC analysis of phospho-H3 and Ki67 confirmed FLT-PET results, indicating a decrease in proliferation the day after the final irinotecan treatment. Increased apoptosis monitored by caspase-3 was observed after day 15 with irinotecan treatment. CONCLUSIONS: FLT-PET may be a better method than FDG-PET for assessing treatment response to irinotecan. Changes in imaging occur before changes in tumor volume.


Asunto(s)
Camptotecina/análogos & derivados , Neoplasias Colorrectales/diagnóstico por imagen , Neoplasias Colorrectales/tratamiento farmacológico , Didesoxinucleósidos , Fluorodesoxiglucosa F18 , Imagen Multimodal , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Ensayos Antitumor por Modelo de Xenoinjerto , Animales , Camptotecina/farmacología , Camptotecina/uso terapéutico , Línea Celular Tumoral , Neoplasias Colorrectales/patología , Didesoxinucleósidos/farmacocinética , Femenino , Fluorodesoxiglucosa F18/farmacocinética , Humanos , Inmunohistoquímica , Irinotecán , Ratones , Ratones SCID , Carga Tumoral
16.
Cancer Chemother Pharmacol ; 69(4): 911-21, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22080168

RESUMEN

Tyrosine kinase inhibitors represent a class of targeted therapy that has proven to be successful for cancer treatment. Linifanib is a novel, orally active multi-targeted receptor tyrosine kinase (RTK) inhibitor that exhibits potent antitumor and antiangiogenic activities against a broad spectrum of experimental tumors and malignancies in patients. The compound is currently being evaluated in phase 2 and 3 clinical trials. To investigate the effectiveness of linifinib against gliomas and the mechanism of drug action, we characterized treatment-induced antitumor and antiangiogenic responses to linifanib in an orthotopic rat glioma model. The effect of linifanib treatment on tumor growth was determined by tumor volume assessment using anatomical magnetic resonance imaging (MRI). Changes in tumor microvessel function were evaluated with dynamic contrast-enhanced MRI (DCE-MRI). Immunohistochemistry (IHC) was applied to excised tumor samples to examine underlying changes in vascular structures and target receptor expression. Linifanib (10 mg/kg) given twice daily inhibited tumor growth following treatment for 7 days with tumor volumes being 149 ± 30 and 66 ± 7 mm(3) for vehicle-and linifanib-treated groups, respectively. A significant reduction of 37 ± 13% in tumor perfusion and microvessel permeability (measured by K (trans)) was observed as early as 2 h after administration compared with vehicle treatment. Continuous linifanib administration further reduced K (trans) at later time points until the end of the study (7 days post-treatment). At day 7, K (trans) was reduced by 75 ± 32% for linifanib treatment compared with vehicle treatment. Significant reduction in total blood vessel density and improved vessel wall integrity were observed, and staining for target receptor expression confirmed inhibition of phospho VEGFR-2 and PDGFR-ß by linifanib treatment. These results demonstrate significant antitumor and antiangiogenic activity against gliomas by linifanib, a property that may result from the inhibition of VEGFR-2 and PDGFR-ß-mediated vascular changes. DCE-MRI measured K (trans) changes at early treatment stages may be a useful pharmacodynamic marker for linifanib activity in clinical trials, and basal K (trans) may provide predictive value for tumor progression.


Asunto(s)
Neoplasias Encefálicas/irrigación sanguínea , Neoplasias Encefálicas/tratamiento farmacológico , Glioma/irrigación sanguínea , Glioma/tratamiento farmacológico , Indazoles/farmacología , Compuestos de Fenilurea/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Animales , Neoplasias Encefálicas/enzimología , Procesos de Crecimiento Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Glioma/enzimología , Glioma/patología , Inmunohistoquímica , Angiografía por Resonancia Magnética , Neovascularización Patológica/tratamiento farmacológico , Neovascularización Patológica/patología , Ratas , Ratas Endogámicas F344 , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Am J Cardiol ; 104(4): 565-70, 2009 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-19660613

RESUMEN

This report presents the procedural results from the AMADEUS trial that support coronary sinus (CS)-based percutaneous mitral annuloplasty. Despite therapeutic advances, functional mitral regurgitation (MR) continues to be a significant clinical problem for patients with dilated cardiomyopathy. CS approaches to mitral valve repair have been viewed with skepticism because of the distance of the CS/great cardiac vein from the mitral valve annulus and the potential to compress a coronary artery. This report presents the procedural results from the AMADEUS trial that support CS-based percutaneous mitral annuloplasty. Patients who met the inclusion criteria were eligible to receive a mitral annuloplasty device. Transesophageal echocardiography was used to assess changes in MR, angiography was used to assess the coronary arteries, and multislice computed tomography was used to evaluate the anatomic relations between the coronary venous system and the mitral valve. Acute MR reduction (grade 3.0 +/- 0.6 to 2.0 +/- 0.8, p <0.0001) and permanent implantation were achieved in 30 of 43 patients in whom an attempt was made. Additional measurements in 20 patients with implants showed reductions in the vena contracta (0.69 +/- 0.29 to 0.46 +/- 0.26 cm, p <0.0001), effective regurgitant orifice area (0.33 +/- 0.17 to 0.19 +/- 0.08 cm(2), p <0.0001), regurgitant volume (40 +/- 20 to 24 +/- 11 ml, p = 0.0005), and jet area/left atrial area (45 +/- 13% to 32 +/- 12%, p <0.0001). The coronary arteries were crossed in 36 patients (84%). Arterial compromise contributed to a lack of implantation in 6 patients (14%). No difference was found in the CS/great cardiac vein position relative to the annulus between the patients who did and did not have a reduction in MR. In conclusion, percutaneous mitral annuloplasty reduces MR and permanent implantation can be achieved in most eligible patients.


Asunto(s)
Angioplastia Coronaria con Balón , Cardiomiopatía Dilatada/complicaciones , Seno Coronario , Implantación de Prótesis de Válvulas Cardíacas , Insuficiencia de la Válvula Mitral/terapia , Anciano , Cardiomiopatía Dilatada/diagnóstico , Cardiomiopatía Dilatada/fisiopatología , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia de la Válvula Mitral/diagnóstico , Insuficiencia de la Válvula Mitral/etiología , Volumen Sistólico , Resultado del Tratamiento
18.
Circulation ; 120(4): 326-33, 2009 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-19597051

RESUMEN

BACKGROUND: Functional mitral regurgitation (FMR), a well-recognized component of left ventricular remodeling, is associated with increased morbidity and mortality in heart failure patients. Percutaneous mitral annuloplasty has the potential to serve as a therapeutic adjunct to standard medical care. METHODS AND RESULTS: Patients with dilated cardiomyopathy, moderate to severe FMR, an ejection fraction <40%, and a 6-minute walk distance between 150 and 450 m were enrolled in the CARILLON Mitral Annuloplasty Device European Union Study (AMADEUS). Percutaneous mitral annuloplasty was achieved through the coronary sinus with the CARILLON Mitral Contour System. Echocardiographic FMR grade, exercise tolerance, New York Heart Association class, and quality of life were assessed at baseline and 1 and 6 months. Of the 48 patients enrolled in the trial, 30 received the CARILLON device. Eighteen patients did not receive a device because of access issues, insufficient acute FMR reduction, or coronary artery compromise. The major adverse event rate was 13% at 30 days. At 6 months, the degree of FMR reduction among 5 different quantitative echocardiographic measures ranged from 22% to 32%. Six-minute walk distance improved from 307+/-87 m at baseline to 403+/-137 m at 6 months (P<0.001). Quality of life, measured by the Kansas City Cardiomyopathy Questionnaire, improved from 47+/-16 points at baseline to 69+/-15 points at 6 months (P<0.001). CONCLUSIONS: Percutaneous reduction in FMR with a novel coronary sinus-based mitral annuloplasty device is feasible in patients with heart failure, is associated with a low rate of major adverse events, and is associated with improvement in quality of life and exercise tolerance.


Asunto(s)
Angioplastia Coronaria con Balón/instrumentación , Angioplastia Coronaria con Balón/métodos , Unión Europea , Insuficiencia de la Válvula Mitral/fisiopatología , Insuficiencia de la Válvula Mitral/terapia , Válvula Mitral/fisiología , Anciano , Anciano de 80 o más Años , Estimulación Cardíaca Artificial/métodos , Femenino , Estudios de Seguimiento , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Implantación de Prótesis de Válvulas Cardíacas/métodos , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia de la Válvula Mitral/epidemiología , Estudios Prospectivos
19.
J Med Chem ; 51(13): 3777-87, 2008 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-18557606

RESUMEN

7-Aminopyrazolo[1,5- a]pyrimidine urea receptor tyrosine kinase inhibitors have been discovered. Investigation of structure-activity relationships of the pyrazolo[1,5- a]pyrimidine nucleus led to a series of 6-(4- N, N'-diphenyl)ureas that potently inhibited a panel of vascular endothelial growth factor receptor (VEGFR) and platelet-derived growth factor receptor (PDGFR) kinases. Several of these compounds, such as 34a, are potent inhibitors of kinase insert domain-containing receptor tyrosine kinase (KDR) both enzymatically (<10 nM) and cellularly (<10 nM). In addition, compound 34a possesses a favorable pharmacokinetic profile and demonstrates efficacy in the estradiol-induced murine uterine edema (UE) model (ED 50 = 1.4 mg/kg).


Asunto(s)
Compuestos de Fenilurea/síntesis química , Compuestos de Fenilurea/farmacología , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Pirazoles/síntesis química , Pirazoles/farmacología , Pirimidinas/síntesis química , Pirimidinas/farmacología , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/metabolismo , Animales , Edema/tratamiento farmacológico , Edema/enzimología , Femenino , Masculino , Ratones , Modelos Moleculares , Estructura Molecular , Compuestos de Fenilurea/química , Compuestos de Fenilurea/uso terapéutico , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/uso terapéutico , Pirazoles/química , Pirazoles/uso terapéutico , Pirimidinas/química , Pirimidinas/uso terapéutico , Proteínas Tirosina Quinasas Receptoras/química , Relación Estructura-Actividad , Urea/química , Enfermedades Uterinas/tratamiento farmacológico , Enfermedades Uterinas/enzimología
20.
Bioorg Med Chem Lett ; 18(1): 386-90, 2008 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18023347
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