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1.
Magn Reson Med ; 89(6): 2281-2294, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36688262

RESUMEN

PURPOSE: This work aims to explore the effect of Blood Brain Barrier (BBB) opening using ultrasound combined with microbubbles injection on cerebral blood flow in rats. METHODS: Two groups of n = 5 rats were included in this study. The first group was used to investigate the impact of BBB opening on the Arterial Spin Labeling (ASL) signal, in particular on the arterial transit time (ATT). The second group was used to analyze the spatiotemporal evolution of the change in cerebral blood flow (CBF) over time following BBB opening and validate these results using DSC-MRI. RESULTS: Using pCASL, a decrease in CBF of up to 29 . 6 ± 15 . 1 % $$ 29.6\pm 15.1\% $$ was observed in the target hemisphere, associated with an increase in arterial transit time. The latter was estimated to be 533 ± 121ms $$ 533\pm 12\mathrm{1ms} $$ in the BBB opening impacted regions against 409 ± 93ms $$ 409\pm 93\mathrm{ms} $$ in the contralateral hemisphere. The spatio-temporal analysis of CBF maps indicated a nonlocal hypoperfusion. DSC-MRI measurements were consistent with the obtained results. CONCLUSION: This study provided strong evidence that BBB opening using microbubble intravenous injection induces a transient hypoperfusion. A spatiotemporal analysis of the hypoperfusion changes allows to establish some points of similarity with the cortical spreading depression phenomenon.


Asunto(s)
Barrera Hematoencefálica , Imagen por Resonancia Magnética , Ratas , Animales , Barrera Hematoencefálica/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Arterias , Isquemia , Circulación Cerebrovascular/fisiología , Marcadores de Spin
2.
Magn Reson Med ; 87(4): 1688-1699, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34825724

RESUMEN

PURPOSE: Proton magnetic resonance spectroscopic imaging (1H MRSI) is a noninvasive technique for assessing tumor metabolism. Manual inspection is still the gold standard for quality control (QC) of spectra, but it is both time-consuming and subjective. The aim of the present study was to assess automatic QC of glioblastoma MRSI data using random forest analysis. METHODS: Data for 25 patients, acquired prospectively in a preradiotherapy examination, were submitted to postprocessing with syngo.MR Spectro (VB40A; Siemens) or Java-based magnetic resonance user interface (jMRUI) software. A total of 28 features were extracted from each spectrum for the automatic QC. Three spectroscopists also performed manual inspections, labeling each spectrum as good or poor quality. All statistical analyses, with addressing unbalanced data, were conducted with R 3.6.1 (R Foundation for Statistical Computing; https://www.r-project.org). RESULTS: The random forest method classified the spectra with an area under the curve of 95.5%, sensitivity of 95.8%, and specificity of 81.7%. The most important feature for the classification was Residuum_Lipids_Versus_Fit, obtained with syngo.MR Spectro. CONCLUSION: The automatic QC method was able to distinguish between good- and poor-quality spectra, and can be used by radiation oncologists who are not spectroscopy experts. This study revealed a novel set of MRSI signal features that are closely correlated with spectral quality.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/radioterapia , Glioblastoma/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética/métodos , Control de Calidad , Reproducibilidad de los Resultados
3.
Nanoscale ; 16(7): 3729-3737, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38294340

RESUMEN

Lanthanide-based macrocycles are successfully incorporated into hybrid polyionic complexes, formed by adding a mixture of zirconium ions to a solution of a double-hydrophilic block copolymer. The resulting nanoobjects with an average radius of approximately 10-15 nm present good colloidal and chemical stability in physiological media even in the presence of competing ions such as phosphate or calcium ions. The final optical and magnetic properties of these objects benefit from both their colloidal nature and the specific properties of the complexes. Hence these new nanocarriers exhibit enhanced T1 MRI contrast, when administered intravenously to mice.


Asunto(s)
Medios de Contraste , Nanoestructuras , Animales , Ratones , Medios de Contraste/química , Luminiscencia , Imagen por Resonancia Magnética/métodos , Polímeros , Iones
4.
Radiother Oncol ; 183: 109665, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37024057

RESUMEN

BACKGROUND AND PURPOSE: All glioblastoma subtypes share the hallmark of aggressive invasion, meaning that it is crucial to identify their different components if we are to ensure effective treatment and improve survival. Proton MR spectroscopic imaging (MRSI) is a noninvasive technique that yields metabolic information and is able to identify pathological tissue with high accuracy. The aim of the present study was to identify clusters of metabolic heterogeneity, using a large MRSI dataset, and determine which of these clusters are predictive of progression-free survival (PFS). MATERIALS AND METHODS: MRSI data of 180 patients acquired in a pre-radiotherapy examination were included in the prospective SPECTRO-GLIO trial. Eight features were extracted for each spectrum: Cho/NAA, NAA/Cr, Cho/Cr, Lac/NAA, and the ratio of each metabolite to the sum of all the metabolites. Clustering of data was performed using a mini-batch k-means algorithm. The Cox model and logrank test were used for PFS analysis. RESULTS: Five clusters were identified as sharing similar metabolic information and being predictive of PFS. Two clusters revealed metabolic abnormalities. PFS was lower when Cluster 2 was the dominant cluster in patients' MRSI data. Among the metabolites, lactate (present in this cluster and in Cluster 5) was the most statistically significant predictor of poor outcome. CONCLUSION: Results showed that pre-radiotherapy MRSI can be used to reveal tumor heterogeneity. Groups of spectra, which have the same metabolic information, reflect the different tissue components representative of tumor burden proliferation and hypoxia. Clusters with metabolic abnormalities and high lactate are predictive of PFS.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/diagnóstico por imagen , Glioblastoma/radioterapia , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/radioterapia , Supervivencia sin Progresión , Estudios Prospectivos , Imagen por Resonancia Magnética/métodos , Lactatos/uso terapéutico , Colina/metabolismo , Colina/uso terapéutico , Ácido Aspártico/metabolismo , Ácido Aspártico/uso terapéutico
5.
Nanoscale ; 15(8): 3893-3906, 2023 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-36723163

RESUMEN

Because of the formation of specific antibodies to poly(ethylene glycol) (PEG) leading to life-threatening side effects, there is an increasing need to develop alternatives to treatments and diagnostic methods based on PEGylated copolymers. Block copolymers comprising a poly(N-vinyl-2-pyrrolidone) (PVP) segment can be used for the design of such vectors without any PEG block. As an example, a poly(acrylic acid)-block-poly(N-vinyl-2-pyrrolidone) (PAA-b-PVP) copolymer with controlled composition and molar mass is synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. Mixing this copolymer with lanthanide cations (Gd3+, Eu3+, Y3+) leads to the formation of hybrid polyion complexes with increased stability, preventing the lanthanide cytotoxicity and in vitro cell penetration. These new nanocarriers exhibit enhanced T1 MRI contrast, when intravenously administered into mice. No leaching of gadolinium ions is detected from such hybrid complexes.


Asunto(s)
Medios de Contraste , Elementos de la Serie de los Lantanoides , Animales , Ratones , Polímeros , Imagen por Resonancia Magnética , Iones
6.
Radiother Oncol ; 181: 109486, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36706959

RESUMEN

BACKGROUND AND PURPOSE: To investigate the feasibility of using a multiapproach analysis combining clinical data, diffusion- and perfusion-weighted imaging, and 3D magnetic resonance spectroscopic imaging to distinguish true tumor progression (TP) from pseudoprogression (PSP) in patients with glioblastoma. MATERIALS AND METHODS: Progression was suspected within 6 months of radiotherapy in 46 of the 180 patients included in the Phase-III SpectroGlio trial (NCT01507506). Choline/creatine (Cho/Cr), choline/N-acetyl aspartate (Cho/NAA) and lactate/N-acetyl aspartate (Lac/NAA) ratios were extracted. Apparent diffusion coefficient (ADC) and cerebral blood volume (CBV) maps were calculated. ADC, relative CBV values and tumor volume (TV) were collected at relapse. Differences between TP and PSP were evaluated using Mann-Whitney tests, and p values were adjusted with Bonferroni correction. RESULTS: Patients with suspected progression underwent a new MRI scan 1 month after the first one. Of these, 28 were classified as PSP, and 18 as TP. After a median follow-up of 41 months, median overall survival was higher in PSP than in TP (25.2 vs 20.3 months; p = 0.0092). Lac/NAA and Cho/Cr ratios were higher in TP than in PSP (1.2 vs 0.5; p = 0.006; and 3 vs 2.2; p = 0.021). After multivariate regression analysis, TV was the most significant predictor of TP vs PSP, and the only one retained in the model (p = 0.028). CONCLUSION: Three spectroscopic ratios could be used to differentiate PSP from TP. TV at relapse was the most predictive factor in the multivariate analysis, and overall survival was higher in PSP than in TP.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Humanos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/radioterapia , Colina , Progresión de la Enfermedad , Glioblastoma/diagnóstico por imagen , Glioblastoma/radioterapia , Imagen por Resonancia Magnética/métodos , Recurrencia Local de Neoplasia
7.
Brain Pathol ; 32(5): e13105, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35773942

RESUMEN

Cell therapy is a promising strategy in the field of regenerative medicine; however, several concerns limit the effective clinical use, namely a valid cell source. The gastrointestinal tract, which contains a highly organized network of nerves called the enteric nervous system (ENS), is a valuable reservoir of nerve cells. Together with neurons and neuronal precursor cells, it contains glial cells with a well described neurotrophic potential and a newly identified neurogenic one. Recently, enteric glia is looked at as a candidate for cell therapy in intestinal neuropathies. Here, we present the therapeutic potential of the ENS as cell source for brain repair, too. The example of stroke is introduced as a brain injury where cell therapy appears promising. This disease is the first cause of handicap in adults. The therapies developed in recent years allow a partial response to the consequences of the disease. The only prospect of recovery in the chronic phase is currently based on rehabilitation. The urgency to offer other treatments is therefore tangible. In the first part of the review, some elements of stroke pathophysiology are presented. An update on the available therapeutic strategies is provided, focusing on cell- and biomaterial-based approaches. Following, the ENS is presented with its anatomical and functional characteristics, focusing on glial cells. The properties of these cells are depicted, with particular attention to their neurotrophic and, recently identified, neurogenic properties. Finally, preliminary data on a possible therapeutic approach combining ENS-derived cells and a biomaterial are presented.


Asunto(s)
Lesiones Encefálicas , Sistema Nervioso Entérico , Accidente Cerebrovascular , Materiales Biocompatibles , Tratamiento Basado en Trasplante de Células y Tejidos , Sistema Nervioso Entérico/fisiología , Humanos , Neuroglía
8.
Front Cell Neurosci ; 16: 871532, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35928573

RESUMEN

Objective: To date, no safe and effective pharmacological treatment has been clinically validated for improving post-stroke neurogenesis. Growth factors are good candidates but low safety has limited their application in the clinic. An additional restraint is the delivery route. Intranasal delivery presents many advantages. Materials and Methods: A brain lesion was induced in twenty-four rats. Nerve growth factor (NGF) 5 µg/kg/day or vehicle was given intranasally from day 10 post-lesion for two periods of five weeks, separated by a two-week wash out period with no treatment. Lesion volume and atrophy were identified by magnetic resonance imaging (MRI). Anxiety and sensorimotor recovery were measured by behavior tests. Neurogenesis, angiogenesis and inflammation were evaluated by histology at 12 weeks. Results: Remarkable neurogenesis occurred and was visible at the second and third months after the insult. Tissue reconstruction was clearly detected by T2 weighted MRI at 8 and 12 weeks post-lesion and confirmed by histology. In the new tissue (8.1% of the lesion in the NGF group vs. 2.4%, in the control group at 12 weeks), NGF significantly increased the percentage of mature neurons (19% vs. 7%). Angiogenesis and inflammation were not different in the two groups. Sensorimotor recovery was neither improved nor hampered by NGF during the first period of treatment, but NGF treatment limited motor recovery in the second period. Interpretation: The first five-week period of treatment was very well tolerated. This study is the first presenting the effects of a long treatment with NGF and has shown an important tissue regeneration rate at 8 and 12 weeks post-injury. NGF may have increased neuronal differentiation and survival and favored neurogenesis and neuron survival through subventricular zone (SVZ) neurogenesis or reprogramming of reactive astrocytes. For the first time, we evidenced a MRI biomarker of neurogenesis and tissue reconstruction with T2 and diffusion weighted imaging.

9.
Transl Stroke Res ; 12(1): 98-111, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32249405

RESUMEN

Ischemic stroke mostly affects the primary motor cortex and descending motor fibres, with consequent motor impairment. Pre-clinical models of stroke with reproducible and long-lasting sensorimotor deficits in higher-order animals are lacking. We describe a new method to induce focal brain damage targeting the motor cortex to study damage to the descending motor tracts in the non-human primate. Stereotaxic injection of malonate into the primary motor cortex produced a focal lesion in middle-aged marmosets (Callithrix jacchus). Assessment of sensorimotor function using a neurological scale and testing of forelimb dexterity and strength lasted a minimum of 12 weeks. Lesion evolution was followed by magnetic resonance imaging (MRI) at 24 h, 1 week, 4 and 12 weeks post-injury and before sacrifice for immunohistochemistry. Our model produced consistent lesions of the motor cortex, subcortical white matter and caudate nucleus. All animals displayed partial spontaneous recovery with long lasting motor deficits of force (54% loss) and dexterity (≈ 70% loss). Clearly visible T2 hypointensity in the white matter was observed with MRI and corresponded to areas of chronic gliosis in the internal capsule and lenticular fasciculus. We describe a straightforward procedure to reproducibly injure the motor cortex in the marmoset monkey, causing long-lasting motor deficits. The MRI signature reflects Wallerian degeneration and remote injury of corticospinal and corticopontine tracts, as well as subcortical motor loops. Our model may be suitable for the testing of therapies for post-stroke recovery, particularly in the chronic phase.


Asunto(s)
Modelos Animales de Enfermedad , Fuerza de la Mano/fisiología , Accidente Cerebrovascular Isquémico/inducido químicamente , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Malonatos/toxicidad , Animales , Callithrix , Femenino , Estudios de Seguimiento , Masculino , Malonatos/administración & dosificación , Reproducibilidad de los Resultados , Técnicas Estereotáxicas/normas
10.
Int J Cardiol ; 300: 245-251, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31806281

RESUMEN

BACKGROUND: Insulin-like Growth Factor Binding Protein 2 (IGFBP2) showed greater heart failure (HF) diagnostic accuracy than the "grey zone" B-type natriuretic peptides, and may have prognostic utility as well. OBJECTIVES: To determine if IGFBP2 provides independent information on cardiovascular mortality in HF. METHODS: A retrospective study of 870 HF patients from 3 independent international cohorts. Presentation IGFBP2 plasma levels were measured by ELISA, and patients were followed from 1 year (Maastricht, Netherlands) to 6 years (Atlanta, GA, USA and Toulouse, France). Multivariate analysis, Net Reclassification Improvement (NRI) and Integrated Discrimination Improvement (IDI) were performed in the 3 cohorts. The primary outcome was cardiovascular mortality. RESULTS: In multivariate Cox proportional hazards analysis, the highest quartile of IGFBP2 was associated with mortality in the Maastricht cohort (adjusted hazard ratio 1.69 (95% CI, 1.18-2.41), p = 0.004) and in the combined Atlanta and Toulouse cohorts (adjusted hazard ratio 2.04 (95%CI, 1.3-3.3), p = 0.003). Adding IGFBP2 to a clinical model allowed a reclassification of adverse outcome risk in the Maastricht cohort (NRI = 18.7% p = 0.03; IDI = 3.9% p = 0.02) and with the Atlanta/Toulouse patients (NRI of 40.4% p = 0.01, 31,2% p = 0.04, 31.5% p = 0,02 and IDI of 2,9% p = 0,0005, 3.1% p = 0,0005 and 4,2%, p = 0.0005, for a follow-up of 1, 2 and 3 years, respectively). CONCLUSION: In 3 international cohorts, IGFBP2 level is a strong prognostic factor for cardiovascular mortality in HF, adding information to natriuretic monitoring and usual clinical markers, that should be further prospectively evaluated for patients' optimized care.


Asunto(s)
Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/mortalidad , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Internacionalidad , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Francia/epidemiología , Georgia/epidemiología , Insuficiencia Cardíaca/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Países Bajos/epidemiología , Pronóstico , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo
11.
Front Neurol ; 9: 1072, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30619036

RESUMEN

Background: Stroke is the first cause of disability in adults in western countries. Infarct of the internal capsule (IC) may be related to motor impairment and poor prognosis in stroke patients. Functional deficits due to medium-sized infarcts are difficult to predict, except if the specific site of the lesion is taken into account. None of the few pre-clinical models recapitulating this type of stroke has shown clear, reproducible, and long-lasting sensorimotor deficits. Here, we developed a rat model of lacunar infarction within the IC, key structure of the sensorimotor pathways, by precise injection of malonate. Methods: The mitochondrial toxin malonate was injected during stereotactic surgery into the IC of rat brains. Rats were divided in three groups: two groups received malonate solution at 1.5M (n = 12) or at 3M (n = 10) and a sham group (n = 5) received PBS. Three key motor functions usually evaluated following cerebral lesion in the clinic strength, target reaching, and fine dexterity were assessed in rats by a forelimb grip strength test, a skilled reaching task (staircase) for reaching and dexterity, and single pellet retrieval task. Sensorimotor functions were evaluated by a neurological scale. Live brain imaging, using magnetic resonance (MRI), and post-mortem immunohistochemistry in brain slices were performed to characterize the lesion site after malonate injection. Results: Intracerebral injection of malonate produced a 100% success rate in inducing a lesion in the IC. All rats receiving the toxin, regardless the dose injected, had similar deficits in strength and dexterity of the contralateral forepaw, and showed significant neurological impairment. Additionally, only partial recovery was observed with respect to strength, while no recovery was observed for dexterity and neurological deficit. MRI and immunostaining show volume size and precise location of the lesion in the IC, destruction of axonal structures and Wallerian degeneration of fibers in the area above the injection site. Conclusions: This pre-clinical model of lacunar stroke induces a lesion in the IC with measurable and reproducible sensorimotor deficits, and limited recovery with stabilization of performance 2 weeks post-injury. Future therapies in stroke may be successfully tested in this model.

12.
Sci Rep ; 8(1): 7894, 2018 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-29784904

RESUMEN

Identification of novel circulating biomarkers predicting death and major cardio-metabolic events in obese patients with heart failure (HF) remains a research priority. In this study, we compared multi-marker profile of non-obese (NOB) and obese (OB) HF patients in relation to mortality outcome. The new multiplex proximity extension assay technology was used to analyze the levels of 92 proteins in plasma samples from HF patients according to body mass index (BMI) categories. At 2-year follow-up, all-cause mortality rates were significantly greater in NOB patients (BMI < 30 kg/m2) compared to the OB patients (BMI > 30 kg/m2) with HF (odds ratio 26; 95% CI: 1.14-624, p < 0,04). Quantitative proteomic analysis revealed thirteen distinct proteins expression profiles of OB and NOB HF patients. Among these proteins, RAGE, CXCL6, CXCL1, CD40, NEMO, VEGF-A, KLK6, PECAM1, PAR1, MMP1, BNP and NTproBNP were down-regulated, whereas leptin was up-regulated in OB HF patients. In addition, an inverse correlation between plasma BNP levels and leptin in OB HF patients was observed (r = -0.58 p = 0.02). This study identifies specific plasma protein signature in OB and NOB patients with HF in relation to mortality outcome.


Asunto(s)
Biomarcadores/sangre , Insuficiencia Cardíaca/diagnóstico , Obesidad/complicaciones , Proteoma/análisis , Proteoma/metabolismo , Anciano , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/etiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
13.
Oxid Med Cell Longev ; 2017: 8536910, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28660008

RESUMEN

The aim of this work was to study the vascular effects of dietary supplementation of a nonalcoholic red wine polyphenol extract, Provinols, in Zucker fatty (ZF) obese rats. ZF or lean rats received diet supplemented or not with Provinols for 8 weeks. Vasoconstriction in response to phenylephrine (Phe) was then assessed in small mesenteric arteries (SMA) and the aorta with emphasis on the contribution of cyclooxygenases (COX). Although no difference in vasoconstriction was observed between ZF and lean rats both in SMA and the aorta, Provinols affected the contribution of COX-derived vasoconstrictor agents. The nonselective COX inhibitor, indomethacin, reduced vasoconstriction in vessels from both groups; however, lower efficacy was observed in Provinols-treated rats. This was associated with a reduction in thromboxane-A2 and 8-isoprostane release. The selective COX-2 inhibitor, NS398, reduced to the same extent vasoconstriction in aortas from ZF and Provinols-treated ZF rats. However, NS398 reduced response to Phe only in SMA from ZF rats. This was associated with a reduction in 8-isoprostane and prostaglandin-E release. Paradoxically, Provinols decreased COX-2 expression in the aorta, while it increased its expression in SMA. We provide here evidence of a subtle and paradoxical regulation of COX pathway by Provinols vessels from obese rats to maintain vascular tone within a physiological range.


Asunto(s)
Inhibidores de la Ciclooxigenasa 2/farmacología , Obesidad/tratamiento farmacológico , Fenilefrina/uso terapéutico , Polifenoles/farmacología , Vino , Animales , Humanos , Obesidad/patología , Fenilefrina/farmacología , Ratas , Ratas Zucker
14.
FASEB J ; 19(8): 1045-7, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15788445

RESUMEN

Adipocytes are known to secrete a number of adipokines, but many adipocyte secretions and their functional importance remain to be characterized. This work shows that human white adipocytes and 3T3-F442A-derived adipocytes produce adrenomedullin (AM) and that AM acts in an autocrine/paracrine way on lipid metabolism by extracellular inactivation of isoproterenol, a beta-adrenergic agonist. AM is described as a counter-regulatory factor involved in the control of cardiovascular homeostasis. This peptide is believed to protect the heart from several complications implicated in obesity-linked cardiomorbidity, such as arterial hypertension, cardiac fibrosis, and decreased sinusal variability. The exact source of circulating AM remains a matter of debate, although endothelial and vascular smooth muscle cells seem to be important sites of production. We show that human adipose cells and 3T3-F442A-derived adipocytes express AM receptors and secrete AM. The function of this feature was investigated in 3T3-F442A cell line at the level of lipolysis regulation. AM inhibited beta-adrenergic-stimulated lipolysis by a nitric oxide (NO)-dependent mechanism, inducing a significant decrease in pD2 value for isoproterenol (8.6 +/- 0.2 vs. 9.8 +/- 0.1, P<0.001). This effect is cGMP-independent since it occurred in the presence of the NO-sensitive guanylate cyclase inhibitor ODQ. It is apparently mediated by a novel extracellular mechanism. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) demonstrated that AM-produced NO oxidized isoproterenol to generate its aminochrome, namely isoprenochrome. Isoprenochrome amounts were increased 3.62 +/- 1.13-fold in cell culture media (P<0.05). We describe for the first time that AM down-regulates lipolysis in adipocytes through the chemical modification of a beta-agonist.


Asunto(s)
Adipocitos/metabolismo , Agonistas Adrenérgicos beta/metabolismo , Lipólisis/fisiología , Óxido Nítrico/fisiología , Péptidos/metabolismo , Péptidos/fisiología , Adipocitos/química , Adrenomedulina , Adulto , Línea Celular , Cromatografía Liquida , Ácidos Grasos no Esterificados/metabolismo , Femenino , Humanos , Hidrazinas/farmacología , Isoproterenol/química , Isoproterenol/metabolismo , Isoproterenol/farmacología , Masculino , Espectrometría de Masas , Óxido Nítrico/farmacología , Oxidación-Reducción , ARN Mensajero/análisis , Receptores Adrenérgicos beta/fisiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
15.
Clin Chim Acta ; 366(1-2): 61-73, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16337167

RESUMEN

Fluorine-19 nuclear magnetic resonance (19F NMR) spectroscopy provides a highly specific tool for the detection, identification and quantification of fluorine-containing drugs and their metabolites in biofluids. The value and difficulties encountered in investigations on drug metabolism are first discussed. Then the metabolism of three fluoropyrimidines in clinical use, 5-fluorouracil, 5-fluorocytosine and capecitabine are reported. Besides the parent drug and the already known fluorinated metabolites, 12 new metabolites were identified for the first time with 19F NMR in human biofluids. Nine of them can only be observed with this technique: fluoride ion, N-carboxy-alpha-fluoro-beta-alanine, alpha-fluoro-beta-alanine conjugate with deoxycholic acid, 2-fluoro-3-hydroxypropanoic acid, fluoroacetic acid, O2-beta-glucuronide of fluorocytosine, fluoroacetaldehyde hydrate and its adduct with urea, fluoromalonic acid semi-aldehyde adducts with urea. This emphasizes the high analytical potential of 19F NMR for the furtherance in the understanding of fluoropyrimidine catabolic pathways. 19F NMR should also play a role in the therapeutic monitoring of FU and its prodrugs in specific groups of patients, e.g. hemodialyzed patients or patients with deficiency in FU catabolic enzymes.


Asunto(s)
Líquidos Corporales/metabolismo , Flucitosina/farmacocinética , Fluorouracilo/metabolismo , Fluorouracilo/farmacocinética , Espectroscopía de Resonancia Magnética/métodos , Antifúngicos/metabolismo , Antifúngicos/farmacocinética , Antimetabolitos Antineoplásicos/metabolismo , Antimetabolitos Antineoplásicos/farmacocinética , Líquidos Corporales/química , Flucitosina/metabolismo , Flúor/análisis , Humanos
17.
Medicine (Baltimore) ; 95(46): e4965, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27861330

RESUMEN

About 77.9 million (1 in 4) American adults have high blood pressure. High blood pressure is the primary cause of left ventricular hypertrophy (LVH), which represents a strong predictor of future heart failure and cardiovascular mortality. Previous studies have shown an altered metabolic profile in hypertensive patients with LVH. The goal of this study was to identify blood metabolomic LVH biomarkers by H NMR to provide novel diagnostic tools for rapid LVH detection in populations of hypertensive individuals. This cross-sectional study included 48 hypertensive patients with LVH matched with 48 hypertensive patients with normal LV size, and 24 healthy controls. Two-dimensional targeted M-mode echocardiography was performed to measure left ventricular mass index. Partial least squares discriminant analysis was used for the multivariate analysis of the H NMR spectral data. From the H NMR-based metabolomic profiling, signals coming from methylene (-CH2-) and methyl (-CH3) moieties of aliphatic chains from plasma lipids were identified as discriminant variables. The -CH2-/-CH3 ratio, an indicator of the mean length of the aliphatic lipid chains, was significantly higher (P < 0.001) in the LVH group than in the hypertensive group without LVH and controls. Receiver operating characteristic curve showed that a cutoff of 2.34 provided a 52.08% sensitivity and 85.42% specificity for discriminating LVH (AUC = 0.703, P-value < 0.001). We propose the -CH2-/-CH3 ratio from plasma aliphatic lipid chains as a biomarker for the diagnosis of left ventricular remodeling in hypertension.


Asunto(s)
Hipertrofia Ventricular Izquierda/sangre , Lípidos/sangre , Anciano , Biomarcadores/sangre , Estudios Transversales , Femenino , Humanos , Hipertensión/complicaciones , Hipertrofia Ventricular Izquierda/etiología , Masculino , Metabolómica , Persona de Mediana Edad
18.
J Pharm Biomed Anal ; 38(5): 871-91, 2005 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-16087049

RESUMEN

Fluorine-19 or phosphorus-31 NMR (19F NMR or 31P NMR) spectroscopy provides a highly specific tool for identification of fluorine- or phosphorus-containing drugs and their metabolites in biological media as well as a suitable analytical technique for their absolute quantification. This article focuses on the application of in vitro 19F or 31P NMR to the quantitative metabolic studies of some fluoropyrimidine or oxazaphosphorine drugs in clinical use. The first part presents an overview of the advantages (non-destructive and non-selective direct quantitative study of the biological matrices) and limitations (expensive cost of the spectrometers, limited mass or concentration sensitivity) of NMR spectroscopy. The second part deals with the criteria to be considered for successful quantification by NMR (uniform excitation over the entire spectral width of the spectrum, resonance signals properly characterised by taking into account T1 values and avoiding NOE enhancements, optimisation of the data processing, choice of a suitable standard reference). The third and fourth parts report some examples of quantification of 5-fluorouracil, its prodrug capecitabine, 5-fluorocytosine and their metabolites in bulk solutions (biofluids, tissue extracts, perfusates and culture media) and heterogeneous media (excised tissues and packed intact cells) as well as cyclophosphamide and ifosfamide in biofluids. These two parts emphasise the high potential of in vitro 19F or 31P NMR for absolute quantification, in a single run, of all the fluorine- or phosphorus-containing species in the matrices analysed. The limit of quantification in bulk solutions is 1-3 microM for 19F NMR and approximately 10 microM for 31P NMR. In heterogeneous media analysed with 19F NMR, it is 2-5 nmol in excised tissues and cell pellets.


Asunto(s)
Hidrocarburos Fluorados/análisis , Espectroscopía de Resonancia Magnética/métodos , Compuestos Organofosforados/análisis , Animales , Ciclofosfamida/análogos & derivados , Ciclofosfamida/análisis , Flúor , Fluorouracilo/análogos & derivados , Fluorouracilo/análisis , Humanos , Hidrocarburos Fluorados/química , Técnicas In Vitro , Compuestos Organofosforados/química , Isótopos de Fósforo
19.
Medicine (Baltimore) ; 94(7): e544, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25700319

RESUMEN

We investigated the impact of heart failure (HF) etiology on the outcome of cardiac rehabilitation (CR) assessed by functional and clinical parameters. Treatment of chronic HF requires multidisciplinary approaches with a recognized role for CR. INCARD is a French study aimed at evaluating the benefits of sustainable CR in coronary (C) and noncoronary patients (NC) treated and educated during a 24-month period of follow-up. Prospective, monocentric patients with HF underwent inpatient physical training followed by a home-based program. Evaluations were performed at inclusion, discharge, 3 months after discharge, and subsequently every 6 months over the 24 months of outpatient rehabilitation.A total of 147 HF patients with left ventricular ejection fraction (LVEF) <40 were admitted to the CR center, 63 accepted to join INCARD (29 C and 34 NC). Although the C participants C having both an echocardiographic LVEF and an initially lower peak VO2, inpatient rehabilitation improved all functional parameters. Only NC showed an improved LVEF during the first 3 months of outpatient-follow-up. The main outcome of the outpatient rehabilitation was a trend toward stabilization of clinical and laboratory parameters with no significant difference between C and NC. This study confirms the benefits of initial HF inpatient rehabilitation and encourages prolonged outpatient monitoring. The results on functional parameters suggest exercise training should be conducted regardless of the HF etiology.


Asunto(s)
Insuficiencia Cardíaca/rehabilitación , Pacientes Internos , Adulto , Anciano , Índice de Masa Corporal , Fármacos Cardiovasculares/uso terapéutico , Enfermedad Crónica , Ecocardiografía , Prueba de Esfuerzo , Femenino , Insuficiencia Cardíaca/tratamiento farmacológico , Pruebas de Función Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Educación del Paciente como Asunto , Estudios Prospectivos , Factores de Riesgo
20.
PLoS One ; 10(3): e0119160, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25786035

RESUMEN

OBJECTIVE: Galectin-3 (Gal-3) is considered as a myocardial fibrosis biomarker with prognostic value in heart failure (HF). Since aldosterone is a neurohormone with established fibrotic properties, we aimed to investigate if mineralocorticoid receptor antagonists (MRAs) would modulate the prognostic value of Gal-3. METHODS: The IBLOMAVED cohort comprised 427 eligible chronic HF patients (CHF) with echocardiography and heart failure biomarkers assessments (BNP). After propensity score matching CHF patients for cardiovascular risk factors, to form balanced groups, Gal-3 levels were measured at baseline in plasma from patients treated with MRAs (MRA-Plus, n=101) or not (MRA-Neg, n=101). The primary end point was all-cause mortality with a follow-up of 3 years. RESULTS: Gal-3 in plasma from these patients were similar with median values of 14.0 ng/mL [IQR, 9.9-19.3] and 14.4 ng/mL [IQR, 12.3-19.8] (P = 0.132) in MRA-Neg and MRA-Plus, respectively. Patients with Gal-3 ≤17.8 ng/mL had an HR of 1 (reference group) and 1.5 [0.4-5.7] in MRA-Neg and MRA-Plus, respectively (p=0.509). Patients with Gal-3 ≥ 17.8 ng/mL had an HR of 7.4 [2.2-24.6] and 9.0 [2.9-27.8] in MRA-Plus and MRA-Neg, respectively (p=0.539) and a median survival time of 2.4 years [95%CI,1.8-2.4]. Multivariate Cox proportional hazard analysis confirmed that MRA and the interaction term between MRA treatment and Gal-3 >17.8 ng/mL were not factors associated with survival. CONCLUSIONS: MRA treatment did not impair the prognostic value of Gal-3 assessed with a 17.8 ng/mL cut off. Gal-3 levels maintained its strong prognostic value in CHF also in patients treated with MRAs. The significance of the observed lack of an interaction between Gal-3 and treatment effect of MRAs remains to be elucidated.


Asunto(s)
Galectina 3/sangre , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/tratamiento farmacológico , Antagonistas de Receptores de Mineralocorticoides/uso terapéutico , Biomarcadores/sangre , Enfermedad Crónica , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos
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