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1.
Insights Imaging ; 15(1): 207, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143413

RESUMEN

Cardiovascular imaging is exponentially increasing in the diagnosis, risk stratification, and therapeutic management of patients with cardiovascular disease. The European Society of Cardiovascular Radiology (ESCR) is a non-profit scientific medical society dedicated to promoting and coordinating activities in cardiovascular imaging. The purpose of this paper, written by ESCR committees and Executive board members and approved by the ESCR Executive Board and Guidelines committee, is to codify a standardized approach to creating ESCR scientific documents. Indeed, consensus development methods must be adopted to ensure transparent decision-making that optimizes national and global health and reaches a certain scientific credibility. ESCR consensus documents developed based on a rigorous methodology will improve their scientific impact on the management of patients with cardiac involvement. CRITICAL RELEVANCE STATEMENT: This document aims to codify the methodology for producing consensus documents of the ESCR. These ESCR indications will broaden the scientific quality and credibility of further publications and, consequently, the impact on the diagnostic management of patients with cardiac involvement. KEY POINTS: Cardiovascular imaging is exponentially increasing for diagnosis, risk stratification, and therapeutic management. The ESCR is committed to promoting cardiovascular imaging. A rigorous methodology for ESCR consensus documents will improve their scientific impact.

3.
Eur J Appl Physiol ; 121(1): 297-306, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33057877

RESUMEN

PURPOSE: High altitude results in lower barometric pressure and hence partial pressure of O2 decrease can lead to several molecular and cellular changes, such as generation of reactive oxygen species (ROS). Electron Paramagnetic Resonance technique was adopted in the field, to evaluate the effects of acute and sub-acute hypobaric hypoxia (HH) on ROS production by micro-invasive method. Biological biomarkers, indicators of oxidative stress, renal function and inflammation were investigated too. METHODS: Fourteen lowlander subjects (mean age 27.3 ± 5.9 years) were exposed to HH at 3269 m s.l. ROS production, related oxidative damage to cellular components, systemic inflammatory response and renal function were determined through blood and urine profile performed at 1st, 2nd, 4th, 7th, and 14th days during sojourn. RESULTS: Kinetics of changes during HH exposition showed out significant (range p < 0.05-0.0001) increases that at max corresponds to 38% for ROS production rate, 140% for protein carbonyl, 44% for lipid peroxidation, 42% for DNA damage, 200% for inflammatory cytokines and modifications in renal function (assessed by neopterin concentration: 48%). Conversely, antioxidant capacity significantly (p < 0.0001) decreased - 17% at max. CONCLUSION: This 14 days in-field study describes changes of oxidative-stress biomarkers during HH exposure in lowlanders. The results show an overproduction of ROS and consequent oxidative damage to protein, lipids and DNA with a decrease in antioxidant capacity and the involvement of inflammatory status and a transient renal dysfunction. Exposure at high altitude induces a hypoxic condition during acute and sub-acute phases accompanied by molecular adaptation mechanism indicating acclimatization.


Asunto(s)
Mal de Altura/metabolismo , Estrés Oxidativo , Adulto , Mal de Altura/sangre , Mal de Altura/orina , Citocinas/sangre , Daño del ADN , Femenino , Hemoglobinas/metabolismo , Humanos , Masculino , Neopterin/orina , Carbonilación Proteica
4.
Eur J Prosthodont Restor Dent ; 26(3): 122-128, 2018 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-30063306

RESUMEN

This study verified if experimental composites containing calcium phosphate nanoparticles exert a protective effect against enamel demineralization. Three experimental resin-based composites containing 60 vol% of fillers were manipulated. Filler phase was constituted by silanized barium glass and 0%, 10% or 20% (by volume) of dicalcium phosphate dihydrate (DPCD) nanoparticles functionalized with the monomer triethylene glycol dimethacrylate (TEGDMA). Cavities (10 x 2 x 2 mm) were prepared in bovine enamel and restored using one of the experimental materials (n=10). Specimens were exposed to pH cycling (demineralizing solution: pH 5.0/4h, remineralizing solution: pH 7.0/20h, 14 days). Enamel Knoop microhardness (100g/10s) was measured on the surface (SH) and after transversal sectioning up to 90 µm depth (cross-sectional microhardness, CSH). Microhardness values and the percent of microhardness loss were analyzed ANOVA/Tukey test and Student's paired t-test (alpha: 5%). The materials did not differ in respect to SH. Enamel adjacent to DCPD-containing composite restorations showed smaller reductions in CSH (-1.2% to -3.5%) than the enamel from control group (-12.5%), while CSH of enamel restored with resin-modified glass ionomer was similar to the other groups (-4.5%). DCPD-containing composites reduced enamel demineralization in comparison to a conventional composite.


Asunto(s)
Fosfatos de Calcio/química , Resinas Compuestas/química , Esmalte Dental/efectos de los fármacos , Materiales Dentales/química , Animales , Bovinos , Caries Dental/terapia , Esmalte Dental/patología , Dureza , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Ensayo de Materiales , Nanopartículas , Propiedades de Superficie
5.
Front Robot AI ; 5: 40, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-33500926

RESUMEN

This work illustrates the design phases leading to the development of a new YARP device interface along with its client/server implementation. In order to obtain a smoother integration and a more reliable software usability, while avoiding common errors during the design phases, a new interface is created in the YARP network when a new family of devices is introduced.

6.
Eur Rev Med Pharmacol Sci ; 21(21): 4797-4803, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29164584

RESUMEN

OBJECTIVE: Systemic sclerosis (SSc) is characterized by widespread vascular lesions and skin and internal organs fibrosis, including the heart; all cardiac layers, endocardium, myocardium, and pericardium, may be involved. We report the relevance of cardiac MRI findings in scleroderma patients with cardiac symptoms. PATIENTS AND METHODS: 50 patients, all fulfilling the ACR SSc criteria (19 with limited and 31 with diffused skin involvement) were evaluated using a 1.5T MR scanner. Images were acquired before and after contrast medium administration; the exams were considered positive with one or more of these findings: enlarged volumes, reduced EF, regional kinetic anomalies, edema, DE or pericardial effusion. RESULTS: 40 patients (80%) had one or more cardiac abnormalities: 5 patients had myocardial edema; 2 an increased interventricular septum thickness; 22 dilated ventricles or reduced EF; 12 an abnormal regional ventricular motion (2 of these with akinetic segments); 17 a delayed enhancement with different patterns, all without coronary distribution; 22 a pericardial effusion CONCLUSIONS: Pathologic findings were documented in 80% of the cases confirming a high occurrence of abnormal MR data. Myocardial involvement in systemic sclerosis can be assumed by the presence of multiple pathologic MRI findings. CMR seems to be a valuable tool to identify and assess the presence of cardiac involvement.


Asunto(s)
Esclerodermia Sistémica/diagnóstico , Adulto , Anciano , Ecocardiografía , Femenino , Fibrosis , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/fisiopatología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Miocardio/patología , Derrame Pericárdico/diagnóstico , Derrame Pericárdico/diagnóstico por imagen , Derrame Pericárdico/patología , Esclerodermia Sistémica/diagnóstico por imagen , Esclerodermia Sistémica/patología , Adulto Joven
7.
Eng Geol ; 211: 39-49, 2016 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-27594709

RESUMEN

When a severe flood wave completely filled the Ortiglieto reservoir on August 13, 1935, the 14 m high "Sella Zerbino" secondary dam failed catastrophically causing > 100 casualties. Both of the dams, Sella Zerbino-Zerbino Saddle and Bric Zerbino-Zerbino Peak (Fig. 1) were overtopped but only the Sella Zerbino failed whereas the main barrage did not suffer any damage. The lawsuit that followed this tragic event ended with a full acquittal of the dam's designers since the plaintiff experts succeeded in demonstrating that the collapse was due to an extreme rainfall storm of unpredictable intensity. The case was then officially closed and still today the failure of the Sella Zerbino dam is attributed to the unpredictable hydrological event. Recently, Natale and Petaccia (2013) re-examined the case assessing the capacity of the flood spillways which equipped the Bric Zerbino dam. This paper thoroughly reviews the mechanics of the collapse of the Sella Zerbino dam focusing on the stability of the structure. The water pressure underneath the dam and the poor quality of the foundation rock is believed to have played a major role in the sequence of events that ended in the collapse of the barrage.

8.
Transl Med UniSa ; 13: 33-41, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27042431

RESUMEN

Among lifestyle factors, nutrition is one of the most important determinants of health, and represents a pivotal element of cancer risk. Nonetheless, epidemiological evidences of the relationship between several cancers and specific foods and nutrients is still inadequate, and solid conclusions are missing. Indeed, caloric restriction without malnutrition is associated to cancer prevention. Food may be also the primary route of exposure to contaminants such as metals, persistent organic pollutants, and pesticides. Exposuredisease associations and the interplay with genetic susceptibility requires further studies on genetic variation, environment, lifestyle, and chronic disease in order to eliminate and reduce associated health risks, thus contributing to improve health outcomes for the population. A primary nutritional approach for Active and Healthy Ageing (AHA) has been developed by the Nutrition group of the European Innovation Partnership (EIP) on AHA. The working group on lifestyles of the Italian Ministry of Health has developed a comprehensive approach to adequate nutrition using a consensus methodology to collect and integrate the available evidences from the literature and from the Italian experiences at the regional level, to raise the interest of other experts and relevant stakeholders to outline and scale-up joint strategies for a primary nutritional approach to cancer prevention.

9.
Int Endod J ; 48(1): 89-94, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24646329

RESUMEN

AIM: To compare the ion release and mechanical properties of a calcium hydroxide (Dycal) and two calcium silicate (MTA Angelus and Biodentine) cements. METHODOLOGY: Calcium and hydroxyl ion release in water from 24-h set cements were calculated from titration with HCl (n = 3). Calcium release after 7, 14, 21 and 28 days at pH 5.5 and 7.0 was measured using ICP-OES (n = 6). Flexural strength (FS) and modulus (E) were tested after 48-h storage, and compressive strength (CS) was tested after 48 h and 7 days (n = 10). Ion release and mechanical data were subjected to anova/Tukey and Kruskal-Wallis/Mann-Whitney tests, respectively (α = 0.05). RESULTS: Titration curves revealed that Dycal released significantly fewer ions in solution than calcium silicates (P < 0.001). Calcium release remained constant at pH 7.0, whilst at pH 5.5, it dropped significantly by 24% after 21 days (P < 0.05). At pH 5.5, MTA Angelus released significantly more calcium than Dycal (P < 0.01), whilst Biodentine had superior ion release than Dycal at pH 7.0 (P < 0.01). Biodentine had superior flexural strength, flexural modulus and compressive strength than the other cements, whilst MTA Angelus had higher modulus than Dycal (P < 0.001). CONCLUSIONS: Immediate calcium and hydroxyl ion release in solution was significantly lower for Dycal. In general, all materials released constant calcium levels over 28 days, but release from Dycal was significantly lower than Biodentine and MTA Angelus depending on pH conditions. Biodentine had substantially higher strength and modulus than MTA Angelus and Dycal, both of which demonstrated low stress-bearing capabilities.


Asunto(s)
Compuestos de Aluminio/química , Compuestos de Calcio/química , Hidróxido de Calcio/química , Recubrimiento de la Pulpa Dental/métodos , Iones/química , Minerales/química , Óxidos/química , Materiales de Recubrimiento Pulpar y Pulpectomía/química , Silicatos/química , Bismuto , Fuerza Compresiva , Análisis del Estrés Dental , Combinación de Medicamentos , Módulo de Elasticidad , Concentración de Iones de Hidrógeno , Espectrofotometría Atómica
10.
Radiol Med ; 118(5): 752-98, 2013 Aug.
Artículo en Italiano | MEDLINE | ID: mdl-23184241

RESUMEN

Cardiac magnetic resonance (CMR) is considered an useful method in the evaluation of many cardiac disorders. Based on our experience and available literature, we wrote a document as a guiding tool in the clinical use of CMR. Synthetically we describe different cardiac disorders and express for each one a classification, I to IV, depending on the significance of diagnostic information expected.


Asunto(s)
Enfermedades Cardiovasculares/diagnóstico , Imagen por Resonancia Magnética/métodos , Medios de Contraste , Humanos , Italia
11.
Case Rep Obstet Gynecol ; 2012: 472482, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22844625

RESUMEN

Neuraxial techniques of anaesthesia and analgesia are the current choice in obstetrics for efficacy and general low risk of major complications. Concern exists about neuraxial anaesthesia in patients with occult neural tube defects, regarding both labour analgesia and anaesthesia for Caesarean section. Recently, remifentanil infusion has been proposed as an analgesic technique alternative to lumbar epidural, especially when epidural analgesia appears to be contraindicated. Here, we discuss the case of a pregnant woman attending at our institution with occult, symptomatic spinal dysraphism who requested labour analgesia. She was selected for remifentanil intravenous infusion for labour pain and then underwent urgent operative delivery with spinal anaesthesia with no complications.

12.
Radiol Med ; 117(6): 901-38, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22466874

RESUMEN

Cardiac computed tomography (CCT) has grown as a useful means in different clinical contexts. Technological development has progressively extended the indications for CCT while reducing the required radiation dose. Even today there is little documentation from the main international scientific societies describing the proper use and clinical indications of CCT; in particular, there are no complete guidelines. This document reflects the position of the Working Group of the Cardiac Radiology Section of the Italian Society of Radiology concerning the indications for CCT.


Asunto(s)
Enfermedades Cardiovasculares/diagnóstico por imagen , Tomografía Computarizada por Rayos X/estadística & datos numéricos , Humanos , Italia , Dosis de Radiación , Tomografía Computarizada por Rayos X/instrumentación , Tomografía Computarizada por Rayos X/métodos
13.
Radiol Med ; 117(8): 1294-308, 2012 Dec.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-22430684

RESUMEN

PURPOSE: Assessing myocardial viability is crucial in decision making and prognostic restratification after acute myocardial infarction (MI). A number of noninvasive imaging modalities have been employed in viability identification, but contrast-enhanced magnetic resonance (MR) imaging has been shown to be extremely accurate because of its transmural resolution and precise definition of microvascular obstruction. Our purpose was to assess functional recovery after acute MI, with special focus on the role of infarct transmurality and microvascular obstruction. MATERIALS AND METHODS: Forty-six consecutive patients with first acute MI, reperfused by primary percutaneous transluminal coronary angioplasty (PTCA) (n=40) or fibrinolysis (n=6), underwent MR imaging within the first week to assess oedema, microvascular obstruction, function and viability and then again after 4-6 months to assess functional recovery and scar. RESULTS: At first MR examination, postcontrast images were analysed according to three patterns, based on a combination of first-pass and delayed-enhancement data: pattern 1 (normal first pass and late hyperenhancement <50% thickness) identified viable myocardium, whereas pattern 2 (late hyperenhancement >50% thickness, with or without first-pass perfusion defect) and pattern 3 (perfusion defect at first pass and late hypoenhancement) recognised nonviable myocardium, with 93% sensitivity, 75% specificity, 92% positive predictive value and 78% negative predictive value for identifying viable tissue. Furthermore, by dividing pattern 2 into two subpatterns, 2A and 2B, based on absence or presence of microvascular obstruction in >50% transmural infarcts, we were able to better identify the segments without recovery or that were nonviable with a 1.39 relative risk of failed recovery. CONCLUSIONS: After acute MI, not all infarcts with transmurality >50% can be considered nonviable; microvascular obstruction detected at first pass can help to better stratify these cases.


Asunto(s)
Medios de Contraste , Gadolinio DTPA , Imagen por Resonancia Magnética , Infarto del Miocardio/diagnóstico , Angioplastia Coronaria con Balón , Humanos , Infarto del Miocardio/fisiopatología , Sensibilidad y Especificidad , Supervivencia Tisular
14.
Radiol Med ; 117(8): 1309-19, 2012 Dec.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-22327917

RESUMEN

PURPOSE: The exact incidence of myocarditis is unknown, as the diagnosis is frequently delayed or missed. Clinical presentation and disease course are extremely variable, as there may be acute onset with acute coronary syndrome, or cardiogenic shock, or progressive heart failure or arrhythmias. The purpose of this study was to identify prognostic factors on magnetic resonance imaging (MRI) performed in patients with bioptically proven myocarditis at presentation and after 6 months. MATERIALS AND METHODS: Fifty-six consecutive patients with different presentations of myocarditis (20 with acute coronary syndrome, 20 with heart failure, 16 with arrhythmias) were enrolled. All patients underwent B-mode echocardiography (echo) and tissue Doppler imaging, coronarography, ventriculography, endomyocardial biopsy and contrast-enhanced MRI examination, as well as clinical and echo follow-up at 6 months. RESULTS: At 6-month follow-up, patients were divided in two groups according to values of end-systolic volume and ejection fraction: patients with negative remodelling and those with positive remodelling. Late enhancement was found to be an independent predictor of negative remodelling. CONCLUSIONS: Contrast-enhanced MRI is useful both in the diagnosis and as a prognostic indicator in the clinical suspicion of myocarditis.


Asunto(s)
Imagen por Resonancia Magnética , Miocarditis/diagnóstico , Adolescente , Adulto , Anciano , Medios de Contraste , Ecocardiografía Doppler , Femenino , Humanos , Masculino , Persona de Mediana Edad , Miocarditis/diagnóstico por imagen , Miocarditis/fisiopatología , Pronóstico , Función Ventricular Izquierda , Remodelación Ventricular , Adulto Joven
15.
Eur J Echocardiogr ; 12(3): 222-7, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21193485

RESUMEN

AIMS: In 30-40% of patients with acute ischaemic stroke, the cause remains undefined (cryptogenic stroke). Contrast transoesophageal echocardiography (TEE) is considered the gold standard for patent foramen ovale (PFO) detection. Recently, however, cardiac magnetic resonance (CMR) has also been applied to detect PFO. In this study, we compared the diagnostic value of CMR and TEE in detecting PFO in a group of patients with apparently cryptogenic stroke. METHODS AND RESULTS: Twenty-five patients (age 50 ± 13 years, 16 males) with apparently cryptogenic ischaemic stroke underwent contrast-enhanced TEE and contrast CMR for detection of possible PFO. Both imaging studies were performed during Valsalva manoeuvre. PFO grading results were assessed visually both for TEE and for CMR, according to the entity of contrast passage in the left atrium (grade 0 = no PFO; grades 1, 2, and 3 = mild, medium, and wide PFO, respectively). TEE detected PFO in 16 patients (64%). Contrast-enhanced CMR identified a PFO in 7 (44%) of these patients. TEE showed a grade 1 PFO in five patients, a grade 2 PFO in eight patients, and a grade 3 PFO in three patients. Of these patients, CMR failed to identify PFO in all five patients with a grade 1 PFO, in one patient with a grade 2 PFO, and one patient with grade 3 PFO according to TEE. None of the nine patients without PFO at TEE was shown to have a PFO at CMR. When compared with TEE, the present methodology of CMR had a sensitivity of 50%, specificity of 100%, negative predictive value of 31%, and a positive predictive value of 100%. CONCLUSION: Our data suggest that TEE is the cornerstone imaging diagnostic test to detect and characterize PFO in patients with ischaemic stroke, and is shown to be better compared with the current CMR sequences.


Asunto(s)
Ecocardiografía Transesofágica/métodos , Foramen Oval Permeable/diagnóstico por imagen , Foramen Oval Permeable/patología , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Adulto , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/etiología , Estudios de Cohortes , Medios de Contraste , Femenino , Foramen Oval Permeable/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Intensificación de Imagen Radiográfica/métodos , Sensibilidad y Especificidad , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/etiología
16.
J Bacteriol ; 192(12): 3123-31, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20382765

RESUMEN

SSO1273 of Sulfolobus solfataricus was identified as a cell surface-bound protein by a proteomics approach. Sequence inspection of the genome revealed that the open reading frame of sso1273 is associated in an operon-like structure with genes encoding all the remaining components of a canonical protein-dependent ATP-binding cassette (ABC) transporter. sso1273 gene expression and SSO1273 protein accumulation on the cell surface were demonstrated to be strongly induced by the addition of a peptide mixture (tryptone) to the culture medium. The native protein was obtained in multimeric form, mostly hexameric, under the purification conditions used, and it was characterized as an oligopeptide binding protein, named S. solfataricus OppA (OppA(Ss)). OppaA(Ss) possesses typical sequence patterns required for glycosylphosphatidylinositol lipid anchoring, resulting in an N-linked glycoprotein with carbohydrate moieties likely composed of high mannose and/or hybrid complex carbohydrates. OppA(Ss) specifically binds oligopeptides and shows a marked selectivity for the amino acid composition of substrates when assayed in complex peptide mixtures. Moreover, a truncated version of OppA(Ss), produced in recombinant form and including the putative binding domain, showed a low but significant oligopeptide binding activity.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Proteínas Arqueales/metabolismo , Regulación de la Expresión Génica Arqueal/fisiología , Oligopéptidos/metabolismo , Sulfolobus solfataricus/metabolismo , Transportadoras de Casetes de Unión a ATP/genética , Proteínas Arqueales/genética , Clonación Molecular , Unión Proteica , Especificidad por Sustrato
18.
Int J Immunopathol Pharmacol ; 22(2): 521-4, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19505404

RESUMEN

Retroperitoneal fibrosis (RPF) is a disease characterized by inflammatory fibrotic processes affecting the retroperitoneal structures. Familial Mediterranean Fever (FMF) is an autosomal recessive disorder, characterized by fever and attacks of sterile serositis. Colchicine is the only suitable drug for prevention of acute episodes. We describe a case of association between RPF and FMF in a 48-year-old male, in whom therapy with colchicine, besides preventing acute episodes, allowed RPF regression. To date the association between FMF and RPF and the use of colchicine therapy alone for RPF has not been described.


Asunto(s)
Colchicina/uso terapéutico , Fiebre Mediterránea Familiar/tratamiento farmacológico , Fibrosis Retroperitoneal/tratamiento farmacológico , Fiebre Mediterránea Familiar/complicaciones , Fiebre Mediterránea Familiar/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Inducción de Remisión , Fibrosis Retroperitoneal/complicaciones , Fibrosis Retroperitoneal/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
19.
Acta Radiol ; 47(2): 135-44, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16604959

RESUMEN

Caval filters are widely used in the prevention of pulmonary embolism. Filters have proved to be effective, but the complication rate is not negligible. Computed tomography (CT) provides a complete evaluation of the filter, including both caval and extracaval complications. In this review, we describe the normal CT aspect of cava filters, the classification of complications and their CT findings. Technical considerations for adequate CT imaging are also highlighted.


Asunto(s)
Embolia Pulmonar/prevención & control , Tomografía Computarizada por Rayos X , Filtros de Vena Cava , Humanos , Diseño de Prótesis , Falla de Prótesis , Radiografía Intervencional
20.
Auton Autacoid Pharmacol ; 24(2): 45-54, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15458543

RESUMEN

1. Prolonged bed rest or exposure to microgravity may cause several alterations in autonomic nervous system response (ANSR). 2. Hindlimb unloading (HU) rats were used as an animal model of simulated microgravity to investigate ANSR changes. The experiments were carried out to investigate the effects of simulated microgravity on the autonomic nervous response of the perfused mesenteric vascular bed (MVB), vas deferens and the colon and duodenum from 2-week HU rats. 3. In MVB preparations of HU rats, the frequency-dependent increases in perfusion pressure with perivascular nerve stimulation (PNS; 8-40 Hz) were inhibited, whereas the noradrenaline (NA) concentration-dependent (1-100 microM) perfusion pressure increases were potentiated. The latter most probably reflected up-regulation of alpha-adrenergic receptor function. Relaxant responses of NA-precontracted MVB to PNS (4-30 Hz) or isoprenaline were not different between control and HU preparations, while vasodilation induced by the endothelial agonist ACh was reduced. 4. Transmural stimulation (2-40 Hz) induced frequency-dependent twitches of the vas deferens which were reduced in vas deferens of HU rats, while the sensitivity to NA-induced contraction was significantly increased. 5. In the gastroenteric system of HU rat, direct contractile responses to carbachol or tachykinin as well as relaxant or contractile responses to nervous stimulation appeared unchanged both in the proximal colon rings and in duodenal longitudinal strips. 6. In conclusion, HU treatment affects peripheral tissues in which the main contractile mediators are the adrenergic ones such as resistance vessels and vas deferens, probably by reducing the release of neuromediator. This study validates NA signalling impairment as a widespread process in microgravity, which may most dramatically result in the clinical phenotype of orthostatic intolerance.


Asunto(s)
Suspensión Trasera/fisiología , Intestinos/fisiología , Circulación Esplácnica/fisiología , Conducto Deferente/fisiología , Ingravidez , Animales , Relación Dosis-Respuesta a Droga , Técnicas In Vitro , Masculino , Ratas , Ratas Wistar
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