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1.
BMC Cardiovasc Disord ; 15: 43, 2015 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-25971307

RESUMO

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.


Assuntos
Implante de Prótese de Valva Cardíaca/economia , Implante de Prótese de Valva Cardíaca/métodos , Anuloplastia da Valva Mitral/economia , Anuloplastia da Valva Mitral/métodos , Insuficiência da Valva Mitral/cirurgia , Análise Custo-Benefício , Árvores de Decisões , Feminino , Alemanha , Insuficiência Cardíaca/complicações , Implante de Prótese de Valva Cardíaca/instrumentação , Humanos , Masculino , Cadeias de Markov , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/fisiopatologia , Anos de Vida Ajustados por Qualidade de Vida , Sensibilidade e Especificidade
2.
Front Physiol ; 15: 1394707, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827993

RESUMO

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.
Front Physiol ; 15: 1370079, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39100275

RESUMO

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.

4.
Heliyon ; 10(16): e36483, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39253182

RESUMO

Alzheimer's disease (AD) is the most common global dementia and is universally fatal. Most late-stage AD disease-modifying therapies are intravenous and target amyloid beta (Aß), with only modest effects on disease progression: there remains a high unmet need for convenient, safe, and effective therapeutics. Senescent cells (SC) and the senescence-associated secretory phenotype (SASP) drive AD pathology and increase with AD severity. Preclinical senolytic studies have shown improvements in neuroinflammation, tau, Aß, and CNS damage; most were conducted in transgenic rodent models with uncertain human translational relevance. In this study, aged cynomolgus monkeys had significant elevation of biomarkers of senescence, SASP, and neurological damage. Intermittent treatment with the senolytic navitoclax induced modest reversible thrombocytopenia; no serious drug-related toxicity was noted. Navitoclax reduced several senescence and SASP biomarkers, with CSF concentrations sufficient for senolysis. Finally, navitoclax reduced TSPO-PET frontal cortex binding and showed trends of improvement in CSF biomarkers of neuroinflammation, neuronal damage, and synaptic dysfunction. Overall, navitoclax administration was safe and well tolerated in aged monkeys, inducing trends of biomarker changes relevant to human neurodegenerative disease.

5.
J Pharmacol Exp Ther ; 343(3): 617-27, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22935731

RESUMO

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.


Assuntos
Aminopiridinas/farmacologia , Antineoplásicos/farmacologia , Compostos de Fenilureia/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Receptores do Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Quinases da Família src/antagonistas & inibidores , Aminopiridinas/química , Aminopiridinas/farmacocinética , Aminopiridinas/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Aurora Quinase B , Aurora Quinases , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Feminino , Histonas/antagonistas & inibidores , Células Endoteliais da Veia Umbilical Humana , Humanos , Leucemia Experimental/tratamento farmacológico , Leucemia Experimental/enzimologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Estrutura Molecular , Células NIH 3T3 , Compostos de Fenilureia/química , Compostos de Fenilureia/farmacocinética , Compostos de Fenilureia/uso terapêutico , Fatores de Tempo , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Bioorg Med Chem Lett ; 22(14): 4750-5, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22695126

RESUMO

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.


Assuntos
Inibidores de Proteínas Quinases/química , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirazóis/química , Pirimidinas/química , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Aminação , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Aurora Quinase B , Aurora Quinases , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Camundongos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Modelos Moleculares , Estrutura Molecular , Pirimidinas/farmacologia , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
7.
J Cardiovasc Transl Res ; 15(5): 927-943, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35288821

RESUMO

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.


Assuntos
Comunicação
8.
Mol Imaging Biol ; 24(5): 830-841, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35482146

RESUMO

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.


Assuntos
Fluoretos , Inibidores de Proteínas Quinases , Humanos , Animais , Ratos , Adulto , Tirosina Quinase da Agamaglobulinemia/química , Tirosina Quinase da Agamaglobulinemia/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Receptores de Antígenos de Linfócitos B , Tomografia por Emissão de Pósitrons
9.
Circulation ; 120(4): 326-33, 2009 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-19597051

RESUMO

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.


Assuntos
Angioplastia Coronária com Balão/instrumentação , Angioplastia Coronária com Balão/métodos , União Europeia , Insuficiência da Valva Mitral/fisiopatologia , Insuficiência da Valva Mitral/terapia , Valva Mitral/fisiologia , Idoso , Idoso de 80 Anos ou mais , Estimulação Cardíaca Artificial/métodos , Feminino , Seguimentos , Implante de Prótese de Valva Cardíaca/instrumentação , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/epidemiologia , Estudos Prospectivos
10.
Artigo em Inglês | MEDLINE | ID: mdl-32110775

RESUMO

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.

11.
Bioorg Med Chem Lett ; 18(1): 386-90, 2008 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18023347
12.
Mol Cancer Ther ; 17(4): 795-805, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29483208

RESUMO

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.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Glioblastoma/tratamento farmacológico , Imunoconjugados/farmacologia , Oligopeptídeos/química , Animais , Anticorpos Monoclonais Humanizados/química , Apoptose , Proliferação de Células , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/imunologia , Feminino , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Imunoconjugados/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
13.
J Med Chem ; 50(7): 1584-97, 2007 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-17343372

RESUMO

In our continued efforts to search for potent and novel receptor tyrosine kinase (RTK) inhibitors as potential anticancer agents, we discovered, through a structure-based design, that 3-aminoindazole could serve as an efficient hinge-binding template for kinase inhibitors. By incorporating an N,N'-diaryl urea moiety at the C4-position of 3-aminodazole, a series of RTK inhibitors were generated, which potently inhibited the tyrosine kinase activity of the vascular endothelial growth factor receptor and the platelet-derived growth factor receptor families. A number of compounds with potent oral activity were identified by utilizing an estradiol-induced mouse uterine edema model and an HT1080 human fibrosarcoma xenograft tumor model. In particular, compound 17p (ABT-869) was found to possess favorable pharmacokinetic profiles across different species and display significant tumor growth inhibition in multiple preclinical animal models.


Assuntos
Inibidores da Angiogênese/síntese química , Indazóis/síntese química , Compostos de Fenilureia/síntese química , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Trifosfato de Adenosina/química , Administração Oral , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Animais , Sítios de Ligação , Edema/induzido quimicamente , Edema/patologia , Estradiol , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Indazóis/química , Indazóis/farmacologia , Masculino , Camundongos , Modelos Moleculares , Células NIH 3T3 , Compostos de Fenilureia/química , Compostos de Fenilureia/farmacologia , Fosforilação , Receptores Proteína Tirosina Quinases/química , Receptores Proteína Tirosina Quinases/metabolismo , Relação Estrutura-Atividade , Útero/efeitos dos fármacos , Útero/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Mol Cancer Ther ; 5(4): 995-1006, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16648571

RESUMO

ABT-869 is a structurally novel, receptor tyrosine kinase (RTK) inhibitor that is a potent inhibitor of members of the vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) receptor families (e.g., KDR IC50 = 4 nmol/L) but has much less activity (IC50s > 1 micromol/L) against unrelated RTKs, soluble tyrosine kinases, or serine/threonine kinases. The inhibition profile of ABT-869 is evident in cellular assays of RTK phosphorylation (IC50 = 2, 4, and 7 nmol/L for PDGFR-beta, KDR, and CSF-1R, respectively) and VEGF-stimulated proliferation (IC50 = 0.2 nmol/L for human endothelial cells). ABT-869 is not a general antiproliferative agent because, in most cancer cells, >1,000-fold higher concentrations of ABT-869 are required for inhibition of proliferation. However, ABT-869 exhibits potent antiproliferative and apoptotic effects on cancer cells whose proliferation is dependent on mutant kinases, such as FLT3. In vivo ABT-869 is effective orally in the mechanism-based murine models of VEGF-induced uterine edema (ED50 = 0.5 mg/kg) and corneal angiogenesis (>50% inhibition, 15 mg/kg). In tumor growth studies, ABT-869 exhibits efficacy in human fibrosarcoma and breast, colon, and small cell lung carcinoma xenograft models (ED50 = 1.5-5 mg/kg, twice daily) and is also effective (>50% inhibition) in orthotopic breast and glioma models. Reduction in tumor size and tumor regression was observed in epidermoid carcinoma and leukemia xenograft models, respectively. In combination, ABT-869 produced at least additive effects when given with cytotoxic therapies. Based on pharmacokinetic analysis from tumor growth studies, efficacy correlated more strongly with time over a threshold value (cellular KDR IC50 corrected for plasma protein binding = 0.08 microg/mL, >or=7 hours) than with plasma area under the curve or Cmax. These results support clinical assessment of ABT-869 as a therapeutic agent for cancer.


Assuntos
Inibidores Enzimáticos/farmacologia , Indazóis/farmacologia , Compostos de Fenilureia/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Células 3T3 , Animais , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Córnea , Edema , Feminino , Camundongos , Neovascularização Fisiológica/efeitos dos fármacos , Fosforilação , Receptores do Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Vasos Retinianos/efeitos dos fármacos , Vasos Retinianos/fisiologia , Útero/efeitos dos fármacos , Útero/fisiopatologia
15.
Open Heart ; 3(2): e000411, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27493761

RESUMO

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.

16.
Mol Imaging Biol ; 18(3): 377-85, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26493052

RESUMO

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.


Assuntos
Processamento de Imagem Assistida por Computador/normas , Tomografia por Emissão de Pósitrons/instrumentação , Tomografia por Emissão de Pósitrons/normas , Zircônio/química , Algoritmos , Animais , Feminino , Macaca fascicularis , Imagens de Fantasmas , Radioisótopos
17.
J Am Soc Hypertens ; 10(11): 891-899, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27751879

RESUMO

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.


Assuntos
Síndromes Compartimentais/fisiopatologia , Rim/fisiopatologia , Pré-Eclâmpsia/fisiopatologia , Circulação Renal , Veias Renais/anatomia & histologia , Renina/metabolismo , Variação Anatômica , Circulação Colateral , Endotelina-1/sangue , Endotelina-1/metabolismo , Feminino , Humanos , Isquemia/fisiopatologia , Rim/irrigação sanguínea , Rim/patologia , Obesidade/complicações , Obesidade/fisiopatologia , Pré-Eclâmpsia/prevenção & controle , Gravidez , Veias Renais/fisiopatologia , Sistema Renina-Angiotensina , Fatores de Risco , Sistema Nervoso Simpático/fisiopatologia
18.
Circulation ; 110(19): 3088-92, 2004 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-15505086

RESUMO

BACKGROUND: Functional mitral valve regurgitation plays a key role in the symptomatic severity and progression of heart failure. In an ovine model of dilated cardiomyopathy, we examined the chronic functional consequences of mitral regurgitation reduction using a recently developed novel percutaneous mitral annular reduction (PMAR) device. METHODS AND RESULTS: Fourteen adult sheep were paced right ventricularly at 180 to 190 bpm for 5 weeks, leading to the development of moderate mitral valve regurgitation. After echocardiographic, hemodynamic, and neurohormonal analysis, 9 animals underwent PMAR. All animals were subsequently paced for another 28 days, and a final echocardiographic and hemodynamic study was conducted. Animals that had undergone PMAR showed significantly increased negative and positive dP/dt, whereas pulmonary capillary wedge pressure and mitral valve regurgitation were significantly reduced compared with those at device implant despite continued pacing. In conjunction, significant improvements in plasma norepinephrine and brain natriuretic peptide were apparent. CONCLUSIONS: The application of PMAR in animals with pacing-induced dilated cardiomyopathy and functional mitral valve regurgitation resulted in continued improvements in hemodynamic and neurohormonal parameters.


Assuntos
Cardiomiopatia Dilatada/cirurgia , Valva Mitral/cirurgia , Próteses e Implantes , Animais , Estimulação Cardíaca Artificial/efeitos adversos , Cardiomiopatia Dilatada/sangue , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/etiologia , Seguimentos , Hemodinâmica , Insuficiência da Valva Mitral/sangue , Insuficiência da Valva Mitral/etiologia , Insuficiência da Valva Mitral/cirurgia , Peptídeo Natriurético Encefálico/sangue , Norepinefrina/sangue , Pressão Propulsora Pulmonar , Distribuição Aleatória , Ovinos , Ultrassonografia
19.
J Am Coll Cardiol ; 44(8): 1652-61, 2004 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-15489099

RESUMO

OBJECTIVES: We sought to determine acute and chronic efficacy of a percutaneous mitral annuloplasty (PMA) device in experimental heart failure (HF). Further, we evaluated the potential for adverse effects on left ventricular (LV) function and coronary perfusion. BACKGROUND: Reduction of mitral annular dimension with a PMA device in the coronary sinus may reduce functional mitral regurgitation (MR) in advanced HF. METHODS: Study 1: a PMA device was placed acutely in anesthetized open-chest dogs with rapid pacing-induced HF (n = 6) instrumented for pressure volume analysis. Study 2: in 12 anesthetized dogs with HF, fluoroscopic-guided PMA was performed, and dogs were followed for four weeks with continuing rapid pacing. RESULTS: Study 1: percutaneous mitral annuloplasty reduced annular dimension and severity of MR at baseline and with phenylephrine infusion to increase afterload (MR jet/left atrial [LA] area 26 +/- 1% to 7 +/- 2%, p < 0.05). Pressure volume analysis demonstrated no acute impairment of LV function. Study 2: no device was placed in two dogs because of prototype size limitations. Attempted PMA impaired coronary flow in three dogs. Percutaneous mitral annuloplasty (n = 7) acutely reduced MR (MR jet/LA area 43 +/- 4% to 8 +/- 5%, p < 0.0001), regurgitant volume (14.7 +/- 2.1 ml to 3.1 +/- 0.5 ml, p < 0.05), effective regurgitant orifice area (0.130 +/- 0.010 cm(2) to 0.040 +/- 0.003 cm(2), p < 0.05), and angiographic MR grade (2.8 +/- 0.3 device to 1.0 +/- 0.3 device, p < 0.001). In the conscious state, MR was reduced at four weeks after PMA (MR jet/LA area 33 +/- 3% HF baseline vs. 11 +/- 4% four weeks after device, p < 0.05) CONCLUSIONS: Percutaneous mitral annuloplasty results in acute and chronic reduction of functional MR in experimental HF.


Assuntos
Cateterismo Cardíaco , Circulação Coronária/fisiologia , Ecocardiografia , Insuficiência Cardíaca/cirurgia , Implante de Prótese de Valva Cardíaca , Procedimentos Cirúrgicos Minimamente Invasivos , Insuficiência da Valva Mitral/cirurgia , Valva Mitral/cirurgia , Função Ventricular Esquerda/fisiologia , Animais , Estimulação Cardíaca Artificial , Modelos Animais de Doenças , Cães , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/fisiologia , Valva Mitral/diagnóstico por imagem , Valva Mitral/fisiopatologia , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/fisiopatologia , Desenho de Prótese , Resultado do Tratamento
20.
Emerg Med Clin North Am ; 20(1): 155-76, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11826632

RESUMO

Although there are a variety of neurologic disease processes that the emergency physician should be aware of the most common of these include seizures, closed head injury, headache, and syncope. When one is evaluating a patient who has had a seizure, differentiating between febrile seizures, afebrile seizures, and SE helps to determine the extent of the work-up. Febrile seizures are typically benign, although a diagnosis of meningitis must not be missed. Educating parents regarding the likelihood of future seizures, and precautions to be taken should a subsequent seizure be witnessed, is important. The etiology of a first-time afebrile seizure varies with the patient's age at presentation, and this age-specific differential drives the diagnostic work-up. A follow-up EEG is often indicated, and imaging studies can appropriate on a nonurgent basis. Appropriate management of SE requires a paradigm of escalating pharmacologic therapy, and early consideration of transport for pediatric intensive care services if the seizure cannot be controlled with conventional three-tiered therapy. Closed head injury frequently is seen in the pediatric emergency care setting. The absence of specific clinical criteria to guide the need for imaging makes management of these children more difficult. A thorough history and physical examination is important to uncover risk factors that prompt emergent imaging. Headaches are best approached by assessing the temporal course, associated symptoms, and the presence of persistent neurologic signs. Most patients ultimately are diagnosed with either a tension or migraine headache; however, in those patients with a chronic progressive headache course, an intracranial process must be addressed and pursued with appropriate imaging. Syncope has multiple causes but can generally be categorized as autonomic, cardiac, or noncardiac. Although vasovagal syncope is the most common cause of syncope, vigilance is required to identify those patients with a potentially fatal arrhythmia or with heart disease that predisposes to hypoperfusion. As such, all patients who present with syncope should have an ECG. Additional work-up studies are guided by the results of individual history and physical examination.


Assuntos
Medicina de Emergência/métodos , Doenças do Sistema Nervoso/diagnóstico , Adolescente , Criança , Pré-Escolar , Traumatismos Cranianos Fechados/diagnóstico , Cefaleia/diagnóstico , Cefaleia/terapia , Humanos , Lactente , Doenças do Sistema Nervoso/terapia , Convulsões/diagnóstico , Convulsões/terapia , Estado Epiléptico/diagnóstico , Estado Epiléptico/terapia , Síncope/diagnóstico
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