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1.
Int J Hyperthermia ; 34(4): 373-381, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28758530

RESUMO

We report the development and optimisation of an assay for quantitating iron from iron oxide nanoparticles in biological matrices by using ferene-s, a chromogenic compound. The method is accurate, reliable and can be performed with basic equipment common to many laboratories making it convenient and inexpensive. The assay we have developed is suited for quantitation of iron in cell culture studies with iron oxide nanoparticles, which tend to manifest low levels of iron. The assay was validated with standard reference materials and with inductively coupled plasma-mass spectrometry (ICP-MS) to accurately measure iron concentrations ∼1 × 10-6 g in about 1 × 106 cells (∼1 × 10-12 g Fe per cell). The assay requires preparation and use of a working solution to which samples can be directly added without further processing. After overnight incubation, the absorbance can be measured with a standard UV/Vis spectrophotometer to provide iron concentration. Alternatively, for expedited processing, samples can be digested with concentrated nitric acid before addition to the working solution. Optimization studies demonstrated significant deviations accompany variable digestion times, highlighting the importance to ensure complete iron ion liberation from the nanoparticle or sample matrix to avoid underestimating iron concentration. When performed correctly, this method yields reliable iron ion concentration measurements to ∼2 × 10-6 M (1 × 10-7 g/ml sample).


Assuntos
Compostos Férricos , Ferro/análise , Nanopartículas Metálicas , Triazinas , Bioensaio , Linhagem Celular Tumoral , Colorimetria , Humanos , Espectrometria de Massas , Ácido Nítrico/química , Espectrofotometria
2.
Am Surg ; 89(10): 4171-4178, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37279501

RESUMO

BACKGROUND: The Commission on Cancer (CoC) established quality measures to be reported in National Cancer Database (NCDB) Quality Reporting Tools. Compliance is provided to accredited cancer programs as Cancer Program Practice Profile Reports (CP3R). At the time of this study, the quality metric for gastric cancer (GC) was removal and pathologic examination of 15 regional lymph nodes for resected GC (G15RLN). OBJECTIVE: This study evaluates national trends in quality metric compliance for GC based on CoC CP3R. METHODS: The National Cancer Database (NCDB) was queried from 2004-2017 to identify patients with stage I-III GC who met criteria for inclusion. National trends in compliance were compared. Overall survival (OS) was compared stage for stage. RESULTS: Overall, 42 997 patients with GC qualified. In 2017, 64.5% of patients met compliance with G15RLN compared to 31.4% in 2004. When comparing academic and non-academic institutions, compliance was met 67.0% vs 60.0% of the time in 2017 (P < .01) and 36% vs 30.6% of the time in 2004 (P < .01). On multivariate logistic regression, patients receiving care at academic institutions (OR 1.5, 95% CI 1.4-1.5) and who underwent surgery at institutions in the >75th percentile for case volume (OR 1.5, 95% CI 1.4-1.6) had higher odds of compliance. When stratified by stage, median OS was better across all stages when compliance was met. CONCLUSION: Compliance rates with GC quality measures have improved over time. Compliance with the G15RLN metric is associated with improved OS, stage for stage. Continued efforts to improve compliance rates across all institutions are critical.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Estudos Retrospectivos , Linfonodos/patologia , Modelos Logísticos , Estadiamento de Neoplasias
3.
J Cardiovasc Transl Res ; 15(2): 207-216, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33782857

RESUMO

New mechanistic insight into how the kidney responds to cardiac injury during acute myocardial infarction (AMI) is required. We hypothesized that AMI promotes inflammation and matrix metalloproteinase-9 (MMP9) activity in the kidney and studied the effect of initiating an Impella CP or veno-arterial extracorporeal membrane oxygenation (VA-ECMO) before coronary reperfusion during AMI. Adult male swine were subjected to coronary occlusion and either reperfusion (ischemia-reperfusion; IR) or support with either Impella or VA-ECMO before reperfusion. IR and ECMO increased while Impella reduced levels of MMP-9 in the myocardial infarct zone, circulation, and renal cortex. Compared to IR, Impella reduced myocardial infarct size and urinary KIM-1 levels, but VA-ECMO did not. IR and VA-ECMO increased pro-fibrogenic signaling via transforming growth factor-beta and endoglin in the renal cortex, but Impella did not. These findings identify that AMI increases inflammatory activity in the kidney, which may be attenuated by Impella support.


Assuntos
Oxigenação por Membrana Extracorpórea , Coração Auxiliar , Infarto do Miocárdio , Animais , Masculino , Metaloproteinase 9 da Matriz , Choque Cardiogênico , Suínos
4.
J Cardiovasc Transl Res ; 13(2): 151-157, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31773461

RESUMO

Congestion is a major determinant of clinical outcomes in heart failure (HF). We compared the acute hemodynamic effects of occlusion of the superior (SVC) versus the inferior vena cava (IVC) and tested a novel SVC occlusion system in swine models of HF. IVC occlusion acutely reduced left ventricular (LV) systolic and diastolic pressures, LV volumes, cardiac output (CO), and mean arterial pressure (MAP). SVC occlusion reduced LV diastolic pressure and volumes without affecting CO or MAP. The preCARDIA system is a balloon occlusion catheter and pump console which enables controlled delivery and removal of fluid into the occlusion balloon. At 6, 12, and 18 h, SVC therapy with the system provided a sustained reduction in cardiac filling pressures with stable CO and MAP. Intermittent SVC occlusion is a novel approach to reduce biventricular filling pressures in HF. The VENUS-HF trial will test the safety and feasibility of SVC therapy in HF.


Assuntos
Oclusão com Balão , Insuficiência Cardíaca/terapia , Veia Cava Superior/fisiopatologia , Função Ventricular Esquerda , Pressão Ventricular , Animais , Pressão Arterial , Débito Cardíaco , Modelos Animais de Doenças , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Masculino , Infarto do Miocárdio/complicações , Infarto do Miocárdio/fisiopatologia , Estudo de Prova de Conceito , Sus scrofa , Fatores de Tempo , Pressão Venosa
5.
F1000Res ; 72018.
Artigo em Inglês | MEDLINE | ID: mdl-30542612

RESUMO

Heart failure is a major cause of global morbidity and mortality. Acute myocardial infarction (AMI) is a primary cause of heart failure due in large part to residual myocardial damage despite timely reperfusion therapy. Since the 1970's, multiple preclinical laboratories have tested whether reducing myocardial oxygen demand with a mechanical support pump can reduce infarct size in AMI. In the past decade, this hypothesis has been studied using contemporary circulatory support pumps. We will review the most recent series of preclinical studies in the field which led to the recently completed Door to Unload ST-segment Elevation Myocardial Infarction (DTU-STEMI) safety and feasibility pilot trial.


Assuntos
Coração Auxiliar/tendências , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Pesquisa Translacional Biomédica/métodos , Animais , Humanos , Recuperação de Função Fisiológica , Pesquisa Translacional Biomédica/tendências , Função Ventricular Esquerda
6.
Dis Model Mech ; 11(7)2018 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-29903803

RESUMO

Syngeneic, immunocompetent allograft tumor models recapitulate important aspects of the tumor microenvironment and have short tumor latency with predictable growth kinetics, making them useful for trialing novel therapeutics. Here, we describe surgical techniques for orthotopic and heterotopic pancreatic ductal adenocarcinoma (PDAC) tumor implantation and characterize phenotypes based on implantation site.Mice (n=8 per group) were implanted with 104 cells in the pancreas or flank. Hy15549 and Han4.13 cell lines were derived from primary murine PDAC (Ptf1-Cre; LSL-KRAS-G12D; Trp53 Lox/+) on C57BL/6 and FVB strains, respectively. Single-cell suspension and solid tumor implants were compared. Tumors were treated with two intravenous doses of FOLFIRINOX and responses evaluated.All mice developed pancreatic tumors within 7 days. Orthotopic tumors grew faster and larger than heterotopic tumors. By 3 weeks, orthotopic mice began losing weight, and showed declines in body condition requiring euthanasia starting at 4 weeks. Single-cell injection into the pancreas had near 100% engraftment, but solid tumor implant engraftment was ∼50% and was associated with growth restriction. Orthotopic tumors were significantly more responsive to intravenous FOLFIRINOX compared with heterotopic tumors, with greater reductions in size and increased apoptosis. Heterotopic tumors were more desmoplastic and hypovascular. However, drug uptake into tumor tissue was equivalent regardless of tumor location or degree of fibrosis, indicating that microenvironment differences between heterotopic and orthotopic tumors influenced response to therapy.Our results show that orthotopic and heterotopic allograft locations confer unique microenvironments that influence growth kinetics, desmoplastic response and angiogenesis. Tumor location influences chemosensitivity to FOLFIRINOX and should inform future preclinical trials.This article has an associated First Person interview with the first author of the paper.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fluoruracila/uso terapêutico , Leucovorina/uso terapêutico , Compostos Organometálicos/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Aloenxertos , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Autoenxertos , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/cirurgia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Combinação de Medicamentos , Fluoruracila/administração & dosagem , Fluoruracila/farmacologia , Humanos , Irinotecano , Cinética , Leucovorina/administração & dosagem , Leucovorina/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/farmacologia , Oxaliplatina , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Fenótipo , Transplante Heterotópico
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