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1.
Osteoporos Int ; 33(7): 1619-1624, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35106625

RESUMEN

Transient osteoporosis of the hip (TOH) is usually reported in middle-aged men or during pregnancy as a benign self-limiting condition. Nevertheless, its impact on quality of life in terms of pain and disability is considerable. Also, it can lead to insufficiency fractures or, more rarely, evolve into osteonecrosis. This condition is anecdotally described in the pediatric age and very little is known about how it may affect the growing bone. We herein describe a case of TOH in a 10-year-old child treated at our pediatric rheumatology service and summarize the pediatric cases of TOH previously reported in literature. There are two points of interest in our case report, the first one being the unusual complication of TOH with a femoral physis fracture and the second the complete recovery after the off-label therapy with bisphosphonates. We suggest that interventional medical treatment could be considered in selected cases of juvenile TOH, to prevent any possible irreversible damage on the femoral physis. As far as we know, this is the first report of neridronate employment in children affected by TOH.


Asunto(s)
Osteoporosis , Calidad de Vida , Niño , Difosfonatos/uso terapéutico , Femenino , Articulación de la Cadera , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Osteoporosis/etiología , Embarazo
3.
J Mol Recognit ; 28(6): 393-400, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25726811

RESUMEN

Antibodies play an ever more prominent role in basic research as well as in the biotechnology and pharmaceutical sectors. Characterizing their epitopes, that is, the region that they recognize on their target molecule, is useful for purposes ranging from molecular biology research to vaccine design and intellectual property protection. Solution NMR spectroscopy is ideally suited to the atomic level characterization of intermolecular interfaces and, as a consequence, to epitope discovery. Here, we illustrate how NMR epitope mapping can be used to rapidly and accurately determine protein antigen epitopes. The basic concept is that differences in the NMR signal of an antigen free or bound by an antibody will identify epitope residues. NMR epitope mapping provides more detailed information than mutagenesis or peptide mapping and can be much more rapid than X-ray crystallography. Advantages and drawbacks of this technique are discussed together with practical considerations.


Asunto(s)
Mapeo Epitopo/métodos , Epítopos/química , Regulación Alostérica , Anticuerpos/química , Espectroscopía de Resonancia Magnética , Soluciones
4.
Clin Exp Rheumatol ; 33(6): 769-78, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26690889

RESUMEN

Spondyloarthritis represents a heterogeneous group of articular inflammatory diseases that share common genetic, clinical and radiological features. Recently, novel insights into the epidemiology, pathogenesis and treatment of these diseases have been provided. Herewith, we provide an overview of the most significant literature contributions published over the year.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Antirreumáticos/farmacología , Espondiloartritis , Manejo de la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Espondiloartritis/diagnóstico , Espondiloartritis/tratamiento farmacológico , Espondiloartritis/epidemiología , Espondiloartritis/etiología , Espondiloartritis/fisiopatología
5.
Minerva Med ; 101(1): 49-58, 2010 Feb.
Artículo en Italiano | MEDLINE | ID: mdl-20228720

RESUMEN

The patients undergoing major orthopedic surgery, which includes total hip replacement (THR), total knee replacement (TKR), and hip fracture surgery (HFS), represent a group that has a particularly high risk for venous thromboembolism (VTE), and routine thromboprophylaxis has been standard of care for >20 years. The following article summarizes data derived from numerous randomized clinical trials of thromboprophylaxis following THR, TKR, and HFS; areas of orthopedic surgery for which there are much less data, including knee arthroscopy and isolated lower extremity injuries, are also reviewed.


Asunto(s)
Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Fracturas de Cadera/cirugía , Complicaciones Posoperatorias/prevención & control , Tromboembolia Venosa/prevención & control , Factores de Edad , Humanos , Procedimientos Ortopédicos/efectos adversos
7.
Diabetes ; 50(11): 2619-24, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11679443

RESUMEN

A glomerular permeability defect occurs early in the course of type 1 diabetes and precedes the onset of microalbuminuria and renal morphological changes. Recently, ACE inhibitors have been shown to prevent loss of glomerular membrane permselective function, but the mechanism of this nephroprotective effect is still being debated. The objective of the present study was to evaluate the effects of hypotensive and subhypotensive dosages of the ACE inhibitor quinapril ex vivo and of its active metabolite quinaprilat in vitro on the glomerular albumin permeability (P(alb)) defect in the early phases of experimental diabetes. For the ex vivo study, six groups of male Wistar rats were evaluated for 4 weeks. One group served as a nondiabetic control (C); the other five groups were rendered diabetic and included untreated diabetic rats (D) and diabetic rats receiving quinapril at the dosages of 5 (DQ1), 2.5 (DQ2), 1.25 (DQ3), and 0.625 (DQ4) mg. kg(-1). day(-1). Dosage-dependent effects of quinapril on systolic blood pressure and the glomerular filtration rate were observed. In contrast, control of P(alb) in isolated glomeruli exposed to oncotic gradients, proteinuria, and glomerular and tubular hypertrophy was obtained with subhypotensive dosages (DQ3 and DQ4 groups) of the ACE inhibitor. In the in vitro study, quinaprilat reduced P(alb) significantly in concentration ranges from 10(-6) to 10(-14) mol/l compared with results in control glomeruli. The effect on P(alb) may have occurred by mechanisms different from kidney ACE inhibitor. These study results indicated that ACE inhibitor treatment prevents the early onset of the P(alb) defect in experimental diabetes. This effect seemed to occur independently of systemic or glomerular hemodynamic changes and, at least partially, from kidney ACE inhibition.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/administración & dosificación , Presión Sanguínea/efectos de los fármacos , Nefropatías Diabéticas/patología , Isoquinolinas/administración & dosificación , Glomérulos Renales/patología , Riñón/fisiopatología , Tetrahidroisoquinolinas , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Animales , Glucemia/análisis , Peso Corporal/efectos de los fármacos , Nefropatías Diabéticas/fisiopatología , Relación Dosis-Respuesta a Droga , Isoquinolinas/farmacología , Riñón/enzimología , Riñón/patología , Glomérulos Renales/efectos de los fármacos , Masculino , Peptidil-Dipeptidasa A/sangre , Peptidil-Dipeptidasa A/metabolismo , Permeabilidad , Quinapril , Ratas , Ratas Wistar , Albúmina Sérica/metabolismo
8.
Cardiovasc Res ; 22(3): 226-30, 1988 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3167946

RESUMEN

To assess the acute effects of alcohol on baroreceptor reflex in moderate and heavy drinkers with essential hypertension and in healthy subjects who drank moderately, four groups of age and sex matched subjects were studied. Group 1 consisted of 10 healthy subjects (age range 21-50 (mean 37.4(10.5) years), who usually drank less than 200 g of alcohol per week; group 2 patients (age range 21-50 (mean 37.4(10.3) years) with mild or moderate essential hypertension and whose weekly alcohol consumption was less than 200 g; and groups 3 and 4 patients with mild or moderate hypertension (age range 21-50 (mean 37.2(10.2) years and 21-52 (mean 38.1(10.4) years respectively), who usually drank greater than 700 g of alcohol per week. In groups 1-3 an infusion of alcohol (7 mg.kg-1.min-1) in 500 ml of 5% glucose was administered for 1 h to keep blood concentrations constant (6-7 g.litre-1), whereas in group 4 the dose was doubled (blood concentration 10-11 g.litre-1). Baroreceptor sensitivity was measured by the phenylephrine method before and after alcohol infusion and one or two days later before and after infusion of 500 ml of 5% glucose. In healthy subjects and in moderate drinkers with hypertension the alcohol reduced baroreflex sensitivity significantly (from 17.5(9.5) to 13.8(8.4); p less than 0.01 and from 15(10) to 10.5(6.7) ms.mmHg-1, p less than 0.01 respectively), whereas in the heavy drinkers with hypertension it was significantly reduced only at the highest dose of alcohol (from 12.5(6) to 7.9(3.5) ms.mmHg-1; p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Etanol/farmacología , Hipertensión/fisiopatología , Presorreceptores/efectos de los fármacos , Adulto , Consumo de Bebidas Alcohólicas/fisiología , Presión Sanguínea/efectos de los fármacos , Etanol/administración & dosificación , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Infusiones Intravenosas , Persona de Mediana Edad
9.
Zoonoses Public Health ; 62(5): 365-74, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25220838

RESUMEN

Following reports of human cases of Lyme borreliosis from the Ossola Valley, a mountainous area of Piemonte, north-western Italy, the abundance and altitudinal distribution of ticks, and infection of these vectors with Borrelia burgdorferi sensu lato were evaluated. A total of 1662 host-seeking Ixodes ricinus were collected by dragging from April to September 2011 at locations between 400 and 1450 m above sea level. Additional 104 I. ricinus were collected from 35 hunted wild animals (4 chamois, 8 roe deer, 23 red deer). Tick density, expressed as the number of ticks per 100 m(2), resulted highly variable among different areas, ranging from 0 to 105 larvae and from 0 to 22 nymphs. A sample of 352 ticks (327 from dragging and 25 from wild animals) was screened by a PCR assay targeting a fragment of the 16S rRNA gene of B. burgdorferi s.l. Positive samples were confirmed with a PCR assay specific for the 5S-23S rRNA intergenic spacer region and sequenced. Four genospecies were found: B. afzelii (prevalence 4.0%), B. lusitaniae (4.0%), B. garinii (1.5%) and B. valaisiana (0.3%). Phylogenetic analysis based on the ospC gene showed that most of the Borrelia strains from pathogenic genospecies had the potential for human infection and for invasion of secondary body sites.


Asunto(s)
Borrelia burgdorferi/genética , Borrelia burgdorferi/aislamiento & purificación , Garrapatas/microbiología , Animales , Italia , Datos de Secuencia Molecular
10.
Hypertension ; 26(2): 321-6, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7635542

RESUMEN

Left ventricular hypertrophy with diffuse intermyocardiocytic fibrosis is a feature of uremia. The role of blood pressure and/or other cardiovascular uremic risk factors in cardiac remodeling is still uncertain. To determine the extent to which improvement of kidney function and the control of uremia-related risk factors are associated with a reduction of myocardial injury, we evaluated the effect of dietary protein restriction or the angiotensin-converting enzyme inhibitor lisinopril on cardiac structure in remnant kidney rats. One week after subtotal nephrectomy, Wistar rats were allocated to receive drinking water solution (group 1), 5 mg/kg per day lisinopril (group 2), or a low-protein diet (6%) (group 3) for 12 weeks. Group 2 and 3 showed a comparable efficacy in preventing the expected rise in creatininemia, urinary protein excretion, and glomerulosclerosis. However, hypertension development was prevented only in group 2. Groups 1 and 3 developed a significant (P < .01) increase in left ventricular weight (2.45 +/- 0.1 and 2.5 +/- 0.5 mg/g body wt, respectively) compared with group 2 (1.9 +/- 0.06 mg/g body wt). Cardiac hydroxyporline concentration was also lower in group 2 compared with group 1 (2.07 +/- 0.16 versus 2.73 +/- 0.17 mg/g left ventricular weight, P < .05) but not compared with group 3 (2.59 +/- 0.19 mg/g left ventricular weight). The effect of angiotensin-converting enzyme inhibition on left ventricular mass and intracardiac collagen content appeared to be dissociated from anemia, sympathetic activity, and hyperlipidemia. There was a close relationship between systolic pressure and left ventricular mass; however, no relationship between the degree of cardiac fibrosis and systolic pressure could be determined.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Proteínas en la Dieta/administración & dosificación , Corazón/efectos de los fármacos , Hipertensión/fisiopatología , Lisinopril/administración & dosificación , Uremia/fisiopatología , Animales , Presión Sanguínea/efectos de los fármacos , Corazón/fisiopatología , Hipertensión/etiología , Hipertensión/prevención & control , Masculino , Ratas , Ratas Wistar , Uremia/complicaciones
11.
Am J Med ; 84(1B): 31-5, 1988 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-2829625

RESUMEN

The effect of long-term treatment with indapamide in platelet alpha 2-adrenoceptors has been evaluated in 10 patients with essential hypertension, in a double-blind, cross-over study with placebo. After three months of therapy, indapamide significantly reduced mean blood pressure (from 137 +/- 12 to 116 +/- 6 mm Hg, p less than 0.001), whereas heart rate did not change (from 72 +/- 8 to 73 +/- 7 beats/minute). At the same time, platelet alpha 2-adrenoceptor number increased (from 168.2 +/- 48.4 to 256.8 +/- 14.5 fmol/mg protein, p less than 0.02), whereas the dissociation constant did not change (from 3.79 +/- 2.9 to 4.97 +/- 4.48). The plasma norepinephrine level was significantly reduced after long-term treatment with indapamide (from 275 +/- 118 to 210 +/- 56 pg/ml, p less than 0.02). These results bring about an inhibition of norepinephrine release from sympathetic nerve endings with a likely secondary increase of the number of platelet alpha 2-adrenoceptors.


Asunto(s)
Plaquetas/efectos de los fármacos , Diuréticos/uso terapéutico , Hipertensión/tratamiento farmacológico , Indapamida/uso terapéutico , Receptores Adrenérgicos alfa/efectos de los fármacos , Adulto , Plaquetas/análisis , Presión Sanguínea/efectos de los fármacos , Método Doble Ciego , Evaluación de Medicamentos , Epinefrina/sangre , Femenino , Humanos , Hipertensión/sangre , Masculino , Persona de Mediana Edad , Norepinefrina/sangre , Ensayo de Unión Radioligante , Distribución Aleatoria , Receptores Adrenérgicos alfa/análisis , Factores de Tiempo
12.
J Hypertens ; 10(9): 985-9, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1328380

RESUMEN

OBJECTIVE: To gauge the effectiveness of a new Doppler test for renal artery stenosis (RAS), based on the pulsatility index of the blood flow velocity spectrum within several interlobar arteries of both kidneys. METHODS: Twenty normotensive volunteers and 49 hypertensive patients were investigated with ultrasound. Patients with angiographic signs of RAS underwent bilateral renal vein catheterization for renin measurement. Significant RAS was assumed if lateralization of renal vein renin to the stenotic side was proven. RESULTS: The pulsatility index was higher in the hypertensives without RAS than in normal volunteers. Side differences between both kidneys were within methodological variations with the exception of one case, in whom side difference was > 0.12. The pulsatility index was lower in kidneys with significant RAS than in kidneys without RAS. In most patients with significant unilateral RAS the side difference was < 0.12. In the other patients with a low pulsatility index and a side difference < 0.12 RAS was found to be bilateral upon angiography. Doppler signals were absent in all kidneys with renal occlusion. CONCLUSIONS: A side difference of > or = 0.12 predicts unilateral RAS, whereas the absence of parenchymal Doppler signals indicate occlusive RAS. A low pulsatility index combined with normal side difference may, in hypertensive patients, indicate bilateral RAS. Renovascular hypertension was correctly diagnosed in 84% of the patients and the presence of RAS in 94%.


Asunto(s)
Hipertensión Renovascular/fisiopatología , Obstrucción de la Arteria Renal/diagnóstico por imagen , Arteria Renal/diagnóstico por imagen , Adulto , Anciano , Angiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Flujo Pulsátil/fisiología , Valores de Referencia , Renina/sangre , Ultrasonografía
13.
J Hypertens ; 12(8): 959-64, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7814856

RESUMEN

OBJECTIVE: To gauge the influence of renovascular resistance changes on blood flow velocity pulsatility in kidneys of hypertensive patients by means of the ultrasonic colour and pulsed-wave Doppler method, since we have previously shown in normotensive subjects that the blood flow velocity pulsatility in renal interlobar arteries varies with changes in renovascular resistance. METHODS: In six male patients with primary hypertension, renal blood flow velocity profiles were investigated by means of duplex ultrasound. Single-kidney renovascular resistance was assessed by measurements of split renal function (gamma-camera renography), renal plasma flow (steady-state para-aminohippurate clearance) and cuff blood pressure. The pulsatility index of the blood flow velocity spectrum in the renal interlobar artery and renovascular resistance were measured either at rest, during infusion of angiotensin II, or after angiotensin converting enzyme inhibition. RESULTS: A significant correlation existed between pulsatility index and renovascular resistance (r = 0.50, P < 0.002), which did not improve after correction for the blood pressure pulsatility. Changes of pulsatility index were more closely related (r = 0.64, P < 0.001) to the corresponding changes in renovascular resistance. CONCLUSIONS: With the two-dimensional image-guided colour and pulsed-wave Doppler method it is possible to assess semiquantitatively small intra-individual changes in renovascular resistance in hypertensive patients by means of pulsatility index measurements. Pharmacologically induced alterations in renovascular haemodynamics may therefore be evaluated with this technique.


Asunto(s)
Hipertensión/diagnóstico por imagen , Hipertensión/fisiopatología , Circulación Renal , Resistencia Vascular , Angiotensina II/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Velocidad del Flujo Sanguíneo , Presión Sanguínea/efectos de los fármacos , Gasto Cardíaco/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Flujo Pulsátil , Circulación Renal/efectos de los fármacos , Ultrasonografía , Resistencia Vascular/efectos de los fármacos , Ácido p-Aminohipúrico/sangre
14.
J Hypertens ; 14(9): 1105-10, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8986911

RESUMEN

OBJECTIVE: To evaluate the relationship between the mechanical properties of the carotid artery wall and baroreflex function after acute reduction of blood pressure with lacidipine in essential hypertension. DESIGN: After 15 days of placebo washout, the hypertensive patients underwent a single-blind haemodynamic study before and 90 min after administration of 4 mg lacidipine (a dihydropyridine calcium antagonist). METHODS: Brachial intra-arterial blood pressure was recorded in eight mild-to-moderate essential hypertensive patients aged 40-53 years (mean +/- SEM 46.8 +/- 4.7 years). The carotid pulse diameter was recorded simultaneously by an echo-tracking technique. The mechanical properties of the carotid artery wall were evaluated by calculating Peterson's incremental elastic modulus (Ep) both as an averaged value of 10 heart cycles with stable blood pressure and was the dynamic correlation, on a beat-to-beat basis, of Ep and the systolic blood pressure during a 20 mmHg increase in blood pressure following a bolus injection of phenylephrine. The elastic properties of the carotid artery were investigated further by determining the correlation between the systolic pressure and systolic diameter, beat by beat, during a ramped increase of blood pressure after phenylephrine administration. The baroreceptor reflex sensitivity was measured simultaneously by the Oxford method and by correlating Ep and the electrocardiographic R-R' interval on a beat-to-beat basis during phenylephrine injections. RESULTS: After lacidipine administration Peterson's elastic modulus, measured under resting steady-state conditions, was reduced (18.7 +/- 7.4 versus 16.4 +/- 6 x 10(5) dyne/cm2), whereas the baroreflex sensitivity was unchanged (6.6 +/- 3.3 versus 6.3 +/- 0.2 ms/mmHg) and resetting of the baroreflex had occurred. At the same time, the correlations between the systolic blood pressure and Ep and between the systolic blood pressure and carotid systolic diameter over a 20 mmHg increase in blood pressure were unchanged. Moreover, the correlations between the systolic blood pressure and the R-R' interval and between Ep and R-R' interval during the phenylephrine-induced blood pressure increase did not differ statistically. CONCLUSIONS: The results suggest that the resetting of the baroreflex after the acute reduction in blood pressure caused by lacidipine is dissociated from mechanical changes in the carotid artery wall.


Asunto(s)
Arterias Carótidas/fisiopatología , Hipertensión/fisiopatología , Presorreceptores/fisiopatología , Reflejo , Adulto , Dihidropiridinas/uso terapéutico , Femenino , Humanos , Hipertensión/tratamiento farmacológico , Masculino , Persona de Mediana Edad
15.
J Hypertens ; 17(12 Pt 2): 1925-31, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10703891

RESUMEN

OBJECTIVE: Glomerular hyperfiltration and renal hypertrophy are both considered important in the progression of diabetic nephropathy. The aim of this study was to compare the effects of an equivalent reduction in blood pressure produced by the angiotensin-converting enzyme (ACE) inhibitor spirapril (SPI) and an antihypertensive triple drug combination of hydralazine, reserpine and hydrochlorothiazide (HRH) on kidney function, proteinuria and renal structure in hypertensive diabetic rats. DESIGN AND METHODS: Four groups of animals were evaluated in short-term and long-term studies. In both studies one group served as a non-diabetic hypertensive control (H). The other three groups were rendered diabetic and were allocated to one of the following groups: the first diabetic group received no specific therapy (HD), the second diabetic group was treated with SPI (HD-SPI) and the third diabetic group was treated with HRH (HD-HRH). In each of the two studies the systolic blood pressure (SBP), 24 h urinary total protein, glomerular filtration rate (GFR), glomerular area, proximal tubular area and glomerular sclerosis were evaluated. RESULTS: The blood pressure reduction was equal in rats receiving either SPI or HRH. The GFR, proteinuria, glomerular area and tubular area were significantly increased in the HD group, both in the short-term and the long-term study. In the HD-SPI group the diabetic hyperfiltration and renal hypertrophy responses were prevented. In the HD-HRH group the GFR and proteinuria were slightly reduced in the later phases of diabetes, while the glomerular area and tubular area were not affected. Semiquantitative analysis of renal lesions showed that SPI was more effective than HRH in the prevention of the development of glomerulosclerosis. CONCLUSIONS: The results of this study suggest that the control of early adaptive hyperfiltration and renal hypertrophy by SPI may be relevant in the prevention of glomerulosclerosis.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Angiopatías Diabéticas/tratamiento farmacológico , Nefropatías Diabéticas/fisiopatología , Enalapril/análogos & derivados , Tasa de Filtración Glomerular , Hipertensión/tratamiento farmacológico , Riñón/patología , Animales , Antihipertensivos/farmacología , Presión Sanguínea/efectos de los fármacos , Angiopatías Diabéticas/patología , Angiopatías Diabéticas/fisiopatología , Angiopatías Diabéticas/orina , Progresión de la Enfermedad , Diuréticos , Quimioterapia Combinada , Enalapril/farmacología , Hidralazina/farmacología , Hidroclorotiazida/farmacología , Hipertensión/patología , Hipertensión/fisiopatología , Hipertensión/orina , Hipertrofia , Riñón/fisiopatología , Masculino , Proteinuria/orina , Ratas , Ratas Endogámicas SHR , Reserpina/farmacología , Inhibidores de los Simportadores del Cloruro de Sodio/farmacología
16.
J Hypertens ; 17(12 Pt 2): 1971-6, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10703897

RESUMEN

OBJECTIVE: To study the effects of aortography and of aortic counterflow bolus injection per se on regional and systemic haemodynamics in hypertensives in comparison to normotensive matched controls. DESIGN AND METHODS: Mean blood velocity (MBV) and pulsatility index (PI)--as an index of regional vascular resistance--by the Doppler technique, at the femoral, common carotid and brachial arteries, finger arterial pressure and electrocardiographic R-R' interval were monitored beat-by-beat, before, during and for 3 min following counterflow bolus injections into the abdominal aorta of 40 ml/2.6 s of iopamidol (I), iso-osmolar mannitol (M) and 0.9 N saline (S), in 11 hypertensive and nine normotensive patients. RESULTS: After bolus injection of iopamidol, MBV increased to a peak at 35+/-5 s, both in normotensive (deltaMBV versus baseline +16.7+/-9.9 cm/s; P < 0.01) and in hypertensive subjects (deltaMBV versus baseline: +13.9+/-6.6 cm/s; P < 0.01). At the same time, the PI decreased both in normotensive (deltaPI versus baseline: -4.05+/-2.49; P < 0.01) and in hypertensive subjects (deltaPI versus baseline: -3.02+/-2.25; P < 0.01). After M boluses, the haemodynamic changes were of the same direction and magnitude as I for both groups, while after S the magnitude was approximately 50% lower. No significant differences were observed between normotensive and hypertensive subjects. In other vascular circulations, a 15% increase of the early diastolic backflow in the brachial artery, in phase with the femoral artery haemodynamic changes, was the only evidence of the procedure. Mean arterial pressure decreased and heart rate increased in phase with flow changes of the femoral artery. CONCLUSIONS: (1) The regional flow and systemic pressure changes observed during aortography seem, at least partially, to be due to the hydrodynamic perturbation induced by bolus injection per se. (2) The physical and chemical properties of the contrast media and therefore the probable different shear-stress modifications induced by the fluid injected could explain why the haemodynamic changes were greater after I compared to S and were more similar to M. (3) Hypertensive subjects did not show a different vasoreactive response in comparison to normotensive subjects during aortography.


Asunto(s)
Aortografía , Hemodinámica , Hipertensión/diagnóstico por imagen , Hipertensión/fisiopatología , Anciano , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Arteria Braquial/efectos de los fármacos , Arteria Braquial/fisiología , Medios de Contraste/farmacología , Femenino , Arteria Femoral/efectos de los fármacos , Arteria Femoral/fisiología , Hemodinámica/efectos de los fármacos , Humanos , Yopamidol/farmacología , Masculino , Manitol/farmacología , Persona de Mediana Edad , Concentración Osmolar , Pulso Arterial , Valores de Referencia , Flujo Sanguíneo Regional/efectos de los fármacos , Cloruro de Sodio/farmacología
17.
Exp Gerontol ; 36(3): 571-81, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11250127

RESUMEN

The aim of the present study was to determine whether changes of carotid wall shear stress induced by changes in blood viscosity after diuretic administration cause carotid arterial dilatation in elderly hypertensives, as reported in the cat. Arterial wall shear rate (ultrasound technique, profilmeter FRP III), the systo-diastolic diameter (echotracking technique) and the mean blood flow velocity and volume of the common carotid artery, the blood viscosity (rotational viscometer) and the finger arterial blood pressure (Finapress Ohmeda) were measured in 12 young volunteers (aged 25+/-2 years) and in 12 elderly hypertensives (aged 80+/-4 years) treated with short-acting calcium antagonists up to 24h before the study, both at baseline and after intravenous furosemide infusion (0.5mg/min), when the haematocrit had increased by at least two percentage points. After furosemide administration the mean arterial blood pressure decreased and blood viscosity and carotid systolic shear stress increased in both groups. However, common carotid artery diameter increased only in the young controls but not in the elderly hypertensives. These data show that an increase in carotid shear stress caused by haemoconcentration induces carotid vasodilatation only in young healthy subjects, and not in elderly hypertensives. This effect may be related to impaired endothelium function and/or arterial wall mechanics.


Asunto(s)
Arteria Carótida Común/fisiopatología , Furosemida/farmacología , Hemodinámica/efectos de los fármacos , Hipertensión/fisiopatología , Vasodilatación/efectos de los fármacos , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento , Animales , Presión Sanguínea/efectos de los fármacos , Viscosidad Sanguínea/efectos de los fármacos , Arteria Carótida Común/efectos de los fármacos , Arteria Carótida Común/fisiología , Gatos , Diuréticos/farmacología , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Hipertensión/sangre , Masculino , Estrés Mecánico , Vasodilatación/fisiología
18.
J Hum Hypertens ; 2(3): 171-5, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3236320

RESUMEN

Arterial compliance, assessed by the ratio of stroke volume to pulse pressure, and baroreceptor sensitivity (Oxford method), were determined in ten patients with essential hypertension, treated with placebo or indapamide (2.5 mg/day), in a cross-over, single blind study. After three months of therapy, mean arterial pressure was significantly reduced from 127 +/- 10 to 118 +/- 9 mmHg, (P less than 0.001), as was total peripheral vascular resistance (from 3017 +/- 561 to 2457 +/- 614 dyne/sec/cm-5/m2, P less than 0.001). Significant increases occurred in cardiac index (3.47 +/- 0.55 to 4.03 +/- 0.86 l/min/m2, P less than 0.01), baroreceptor sensitivity assessed with phenylephrine (from 11.69 +/- 7.9 to 15.0 +/- 9.1 msec/mmHg, P less than 0.01) or with nitroglycerine (from 4.77 +/- 1.6 to 7.11 +/- 2.7 msec/mmHg, P less than 0.01) and arterial compliance (from 1.27 +/- 0.42 to 1.55 +/- 0.57, P less than 0.01). A significant direct correlation was found between arterial compliance and baroreceptor sensitivity assessed during induced increase and reduction of BP, both during placebo (r = 0.88, P less than 0.001 and r = 0.77, P less than 0.01, respectively) and during active therapy (r = 0.94, P less than 0.001 and r = 0.92, P less than 0.001, respectively). These results support the conclusion that chronic treatment with indapamide enhances arterial compliances and reduces the heart load and blood vessel stress. The same effect could explain the enhancement of baroreceptor sensitivity promoted by the drug.


Asunto(s)
Arterias/efectos de los fármacos , Diuréticos/uso terapéutico , Hipertensión/tratamiento farmacológico , Indapamida/uso terapéutico , Presorreceptores/efectos de los fármacos , Adulto , Humanos , Hipertensión/fisiopatología , Persona de Mediana Edad , Placebos
19.
Br J Radiol ; 73(870): 588-94, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10911780

RESUMEN

UNLABELLED: The aim was to investigate the regional and systemic haemodynamic consequences of bolus injection of fluids with different physical properties in the course of routine aortography. Iopamidol was compared with an equiosmolar solution of mannitol and with a 0.9 N saline solution. Continuous blood flow and Pulsatility Index (PI), as an index of regional vascular resistance, were measured by Doppler technique. Finger arterial pressure and heart rate were monitored at the time and for 3 min following each intraaortic bolus injections. The patients who underwent routine aortography were grouped according to the site of the flow measurements: common femoral artery, common carotid artery and brachial artery. Flow changes induced by the bolus infusion were evident for all the fluids but only at the femoral artery level. After an immediate (3 +/- 2 s) and brief (2 +/- 2 s) but marked reduction of flow and in-phase increase of PI following the bolus, further haemodynamic changes were observed only in the femoral artery, with a peak at 35 +/- 10 s and returning to baseline values after 70 +/- 15 s, in terms of both increased mean blood velocity and decreased PI. Saline and mannitol induced overall blood velocity alterations of 54% and 80%, respectively, and PI reductions of 44% and 57% compared with those induced by iopamidol. In the other vascular areas there was only a 17 +/- 2% increase of the physiological early diastolic backflow at the brachial artery level. Blood pressure decreased and heart rate increased in phase with the flow changes of the femoral artery. IN CONCLUSION: (1) a dramatic rheodynamic perturbation at the site of injection induces a vasodilating stimulus; (2) the haemodynamic response following injection results in marked vasodilation of only the tributary vascular bed; (3) flow steal may occur from other beds towards the lower limb vascular beds owing to vascular impedance imbalance; (4) a reduction of systemic arterial pressure is induced in phase with the regional vascular events and a reflex increase of the heart rate; and (5) the physical properties of the injected fluids influence the intensity of the perturbation, although the decisive triggering factor is the counterflowing bolus per se.


Asunto(s)
Medios de Contraste/farmacología , Diuréticos Osmóticos/farmacología , Hemodinámica/efectos de los fármacos , Yopamidol/farmacología , Manitol/farmacología , Cloruro de Sodio/farmacología , Aortografía , Femenino , Humanos , Inyecciones Intraarteriales , Soluciones Isotónicas , Masculino , Persona de Mediana Edad , Ultrasonografía Doppler
20.
Minerva Med ; 94(6): 437-44, 2003 Dec.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-14976471

RESUMEN

We report a singular clinical condition observed following a short duration treatment with sulphasalazine (SSZ) in a 64-year-old woman affected by psoriatic arthritis. Two weeks after starting treatment, a high degree, subcontinuous fever occurred, together with systemic discomfort, fatigue, headache, and ultimately a moderate wakefulness impairment. Upon admission to the hospital, a malar rash became evident. Modest notes of hepatotoxicity were also evident. All of the symptoms suddenly resolved after SSZ withdrawal. The markers of hepatitis become negative just 2 months later. It is interesting to note that after dismissal, in order to counteract the severe arthritic conditions and the presence of a type 2 diabetes, a combined therapy with methotrexate and cyclosporin had to be used, with no renal or hepatic side effects and remarkable therapeutic effects. No markers of autoimmunity were found in this patient. The chronology and the clinical events here described may confirm the hypothesis of a idiosyncratic reaction to SSZ, closely resembling a rare, sometimes irreversible, condition known as "the 3 week sulphasalazine syndrome".


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Artritis Psoriásica/tratamiento farmacológico , Erupciones por Medicamentos/etiología , Fiebre/inducido químicamente , Sulfasalazina/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Femenino , Humanos , Persona de Mediana Edad
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