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1.
Cell Death Discov ; 8(1): 94, 2022 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-35241649

RESUMEN

The BAG3- and SIRPα- mediated pathways trigger distinct cellular targets and signaling mechanisms in pancreatic cancer microenvironment. To explore their functional connection, we investigated the effects of their combined blockade on cancer growth in orthotopic allografts of pancreatic cancer mt4-2D cells in immunocompetent mice. The anti-BAG3 + anti-SIRPα mAbs treatment inhibited (p = 0.007) tumor growth by about the 70%; also the number of metastatic lesions was decreased, mostly by the effect of the anti-BAG3 mAb. Fibrosis and the expression of the CAF activation marker α-SMA were reduced by about the 30% in animals treated with anti-BAG3 mAb compared to untreated animals, and appeared unaffected by treatment with the anti-SIRPα mAb alone; however, the addition of anti-SIRPα to anti-BAG3 mAb in the combined treatment resulted in a > 60% (p < 0.0001) reduction of the fibrotic area and a 70% (p < 0.0001) inhibition of CAF α-SMA positivity. Dendritic cells (DCs) and CD8+ lymphocytes, hardly detectable in the tumors of untreated animals, were modestly increased by single treatments, while were much more clearly observable (p < 0.0001) in the tumors of the animals subjected to the combined treatment. The effects of BAG3 and SIRPα blockade do not simply reflect the sum of the effects of the single blockades, indicating that the two pathways are connected by regulatory interactions and suggesting, as a proof of principle, the potential therapeutic efficacy of a combined BAG3 and SIRPα blockade in pancreatic cancer.

2.
J Clin Invest ; 132(3)2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35104805

RESUMEN

Sortilin has been positively correlated with vascular disorders in humans. No study has yet evaluated the possible direct effect of sortilin on vascular function. We used pharmacological and genetic approaches coupled with study of murine and human samples to unravel the mechanisms recruited by sortilin in the vascular system. Sortilin induced endothelial dysfunction of mesenteric arteries through NADPH oxidase 2 (NOX2) isoform activation, dysfunction that was prevented by knockdown of acid sphingomyelinase (ASMase) or sphingosine kinase 1. In vivo, recombinant sortilin administration induced arterial hypertension in WT mice. In contrast, genetic deletion of sphingosine-1-phosphate receptor 3 (S1P3) and gp91phox/NOX2 resulted in preservation of endothelial function and blood pressure homeostasis after 14 days of systemic sortilin administration. Translating these research findings into the clinical setting, we detected elevated sortilin levels in hypertensive patients with endothelial dysfunction. Furthermore, in a population-based cohort of 270 subjects, we showed increased plasma ASMase activity and increased plasma levels of sortilin, S1P, and soluble NOX2-derived peptide (sNOX2-dp) in hypertensive subjects, and the increase was more pronounced in hypertensive subjects with uncontrolled blood pressure. Our studies reveal what we believe is a previously unrecognized role of sortilin in the impairment of vascular function and in blood pressure homeostasis and suggest the potential of sortilin and its mediators as biomarkers for the prediction of vascular dysfunction and high blood pressure.


Asunto(s)
Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Endotelio Vascular/metabolismo , Hipertensión/metabolismo , Lisofosfolípidos/metabolismo , Transducción de Señal , Esfingomielina Fosfodiesterasa/metabolismo , Esfingosina/análogos & derivados , Proteínas Adaptadoras del Transporte Vesicular/genética , Animales , Endotelio Vascular/lesiones , Endotelio Vascular/patología , Endotelio Vascular/fisiopatología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Hipertensión/genética , Hipertensión/fisiopatología , Lisofosfolípidos/genética , Ratones , Ratones Noqueados , Esfingomielina Fosfodiesterasa/genética , Esfingosina/genética , Esfingosina/metabolismo
3.
J Am Heart Assoc ; 9(5): e014923, 2020 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-32078787

RESUMEN

Background High blood pressure (BP) has long been recognized as a major health threat and, particularly, a major risk factor for stroke, cardiovascular disease, and end-organ damage. However, the identification of a novel, alternative, integrative approach for the control of BP and cardiovascular protection is still needed. Methods and Results Sixty-nine uncontrolled hypertension patients, aged 40 to 68 years, on antihypertensive medication were enrolled in 2 double-blind studies. Forty-five were randomized to placebo or a new nutraceutical combination named AkP05, and BP, endothelial function, and circulating nitric oxide were assessed before and at the end of 4 weeks of treatment. Twenty-four patients were randomized to diuretic or AkP05 for 4 weeks and underwent a cardiopulmonary exercise test to evaluate the effects of AkP05 on functional capacity of the cardiovascular, pulmonary, and muscular systems. Vascular and molecular studies were undertaken on mice to characterize the action of the single compounds contained in the AkP05 nutraceutical combination. AkP05 supplementation reduced BP, improved endothelial function, and increased nitric oxide release; cardiopulmonary exercise test revealed that AkP05 increased maximum O2 uptake, stress tolerance, and maximal power output. In mice, AkP05 reduced BP and improved endothelial function, evoking increased nitric oxide release through the PKCα/Akt/endothelial nitric oxide synthase pathway and reducing reactive oxygen species production via NADPH-oxidase inhibition. These effects were mediated by synergism of the single compounds of AkP05. Conclusions This is the first study reporting positive effects of a nutraceutical combination on the vasculature and exercise tolerance in treated hypertensive patients. Our findings suggest that AkP05 may be used as an adjunct for the improvement of cardiovascular protection and to better control BP in uncontrolled hypertension.


Asunto(s)
Suplementos Dietéticos , Tolerancia al Ejercicio/fisiología , Hipertensión/fisiopatología , Hipertensión/terapia , Óxido Nítrico/sangre , Preparaciones de Plantas/uso terapéutico , Adulto , Anciano , Animales , Bacopa , Camellia sinensis , Método Doble Ciego , Prueba de Esfuerzo , Femenino , Ginkgo biloba , Humanos , Hipertensión/sangre , Masculino , Ratones , Persona de Mediana Edad , Fosfatidilserinas/uso terapéutico , Fitoterapia , Especies Reactivas de Oxígeno/sangre
4.
J Cell Physiol ; 228(6): 1359-67, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23192898

RESUMEN

A range of debilitating human diseases is known to be associated with the formation of stable highly organized protein aggregates known as amyloid fibrils. The early prefibrillar aggregates behave as cytotoxic agents and their toxicity appears to result from an intrinsic ability to impair fundamental cellular processes by interacting with cellular membranes, causing oxidative stress and increase in free Ca(2+) that lead to apoptotic or necrotic cell death. However, specific signaling pathways that underlie amyloid pathogenicity remain still unclear. This work aimed to clarify cell impairment induced by amyloid aggregated. To this end, we used a combined proteomic and one-dimensional (1) H-NMR approach on NIH-3T3 cells exposed to prefibrillar aggregates from the amyloidogenic apomyoglobin mutant W7FW14F. The results indicated that cell exposure to prefibrillar aggregates induces changes of the expression level of proteins and metabolites involved in stress response. The majority of the proteins and metabolites detected are reported to be related to oxidative stress, perturbation of calcium homeostasis, apoptotic and survival pathways, and membrane damage. In conclusion, the combined proteomic and (1) H-NMR metabonomic approach, described in this study, contributes to unveil novel proteins and metabolites that could take part to the general framework of the toxicity induced by amyloid aggregates. These findings offer new insights in therapeutic and diagnostic opportunities.


Asunto(s)
Amiloide/toxicidad , Fibroblastos/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Metabolómica/métodos , Proteómica/métodos , Amiloide/metabolismo , Animales , Western Blotting , Electroforesis en Gel Bidimensional , Fibroblastos/metabolismo , Fibroblastos/patología , Ratones , Células 3T3 NIH , Reproducibilidad de los Resultados , Transducción de Señal/efectos de los fármacos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
5.
Rev Sci Instrum ; 79(7): 074501, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18681722

RESUMEN

This paper describes a mechanical monolithic horizontal sensor for geophysical applications developed at the University of Salerno. The instrument is basically a monolithic tunable folded pendulum, shaped with precision machining and electric discharge machining, that can be used both as seismometer and, in a force-feedback configuration, as accelerometer. The monolithic mechanical design and the introduction of laser interferometric techniques for the readout implementation makes it a very compact instrument, very sensitive in the low frequency seismic noise band, with a very good immunity to environmental noises. Many changes have been produced since last version (2007), mainly aimed to the improvement of the mechanics and of the optical readout of the instrument. In fact, we have developed and tested a prototype with elliptical hinges and mechanical tuning of the resonance frequency together with a laser optical lever and a new laser interferometer readout system. The theoretical sensitivity curve for both laser optical lever and laser interferometric readouts, evaluated on the basis of suitable theoretical models, shows a very good agreement with the experimental measurements. Very interesting scientific result is the measured natural resonance frequency of the instrument of 70 mHz with a Q=140 in air without thermal stabilization. This result demonstrates the feasibility of a monolithic folded pendulum sensor with a natural resonance frequency of the order of millihertz with a more refined mechanical tuning.


Asunto(s)
Interferometría/instrumentación , Ruido , Calibración , Diseño de Equipo , Interferometría/métodos , Rayos Láser , Modelos Estadísticos , Reproducibilidad de los Resultados , Proyectos de Investigación , Transductores
6.
J Magn Reson ; 192(2): 294-301, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18396078

RESUMEN

Quantitative information from multi-dimensional NMR experiments can be obtained by peak volume integration. The standard procedure (selection of a region around the chosen peak and addition of all values) is often biased by poor peak definition because of peak overlap. Here we describe a simple method, called CAKE, for volume integration of (partially) overlapping peaks. Assuming the axial symmetry of two-dimensional NMR peaks, as it occurs in NOESY and TOCSY when Lorentz-Gauss transformation of the signals is carried out, CAKE estimates the peak volume by multiplying a volume fraction by a factor R. It represents a proportionality ratio between the total and the fractional volume, which is identified as a slice in an exposed region of the overlapping peaks. The volume fraction is obtained via Monte Carlo Hit-or-Miss technique, which proved to be the most efficient because of the small region and the limited number of points within the selected area. Tests on simulated and experimental peaks, with different degrees of overlap and signal-to-noise ratios, show that CAKE results in improved volume estimates. A main advantage of CAKE is that the volume fraction can be flexibly chosen so as to minimize the effect of overlap, frequently observed in two-dimensional spectra.


Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Método de Montecarlo , Oligopéptidos/química , Hormona Liberadora de Tirotropina/química , Simulación por Computador
7.
Appl Opt ; 47(31): 5853-61, 2008 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-19122727

RESUMEN

We describe a model evaluating changes in the optical isolation of a Faraday isolator when passing from air to vacuum in terms of different thermal effects in the crystal. The changes are particularly significant in the crystal thermal lensing (refraction index and thermal expansion) and in its Verdet constant and can be ascribed to the less efficient convection cooling of the magneto-optic crystal of the Faraday isolator. An isolation decrease by a factor of 10 is experimentally observed in a Faraday isolator that is used in a gravitational wave experiment (Virgo) with a 10 W input laser when going from air to vacuum. A finite element model simulation reproduces with a great accuracy the experimental data measured on Virgo and on a test bench. A first set of measurements of the thermal lensing has been used to characterize the losses of the crystal, which depend on the sample. The isolation factor measured on Virgo confirms the simulation model and the absorption losses of 0.0016 +/- 0.0002/cm for the TGG magneto-optic crystal used in the Faraday isolator.

9.
Neural Netw ; 16(3-4): 297-319, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12672427

RESUMEN

In the last decade, the use of neural networks (NN) and of other soft computing methods has begun to spread also in the astronomical community which, due to the required accuracy of the measurements, is usually reluctant to use automatic tools to perform even the most common tasks of data reduction and data mining. The federation of heterogeneous large astronomical databases which is foreseen in the framework of the astrophysical virtual observatory and national virtual observatory projects, is, however, posing unprecedented data mining and visualization problems which will find a rather natural and user friendly answer in artificial intelligence tools based on NNs, fuzzy sets or genetic algorithms. This review is aimed to both astronomers (who often have little knowledge of the methodological background) and computer scientists (who often know little about potentially interesting applications), and therefore will be structured as follows: after giving a short introduction to the subject, we shall summarize the methodological background and focus our attention on some of the most interesting fields of application, namely: object extraction and classification, time series analysis, noise identification, and data mining. Most of the original work described in the paper has been performed in the framework of the AstroNeural collaboration (Napoli-Salerno).


Asunto(s)
Astronomía/clasificación , Astronomía/métodos , Redes Neurales de la Computación
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