RESUMEN
OBJECTIVES: To test the hypotheses that estimated mean pulmonary arterial pressure (MPAP) decreases and pulmonary vascular maturation, assessed by the ratio of pulmonary arterial flow acceleration time to ejection time (AT/ET ratio), increases after reversal of fetal ductus arteriosus constriction by reducing maternal intake of the causal agent (prostaglandin inhibitors, such as polyphenol-rich foods or non-steroidal anti-inflammatory drugs), and that these effects are independent of gestational age, which are inferences not yet demonstrated in the clinical setting. METHODS: This was a prospective cohort study comparing Doppler echocardiographic ductal flow dynamics, MPAP and pulmonary arterial flow AT/ET ratio in third-trimester fetuses (≥ 28 weeks' gestation) with ductus arteriosus constriction, at the time of diagnosis and after 2 weeks of reduced maternal intake of prostaglandin inhibitors either by suspending the use of pharmacological agents with potential for prostaglandin inhibition or by restricting the consumption of polyphenol-rich foods. MPAP was estimated using the Dabestani equation (MPAP = 90 - (0.62 × AT)), and pulmonary vascular maturity was assessed using the AT/ET ratio, according to reported validation studies. Student's t-test was used for comparison of variables at diagnosis with those after reversal of ductal constriction. Change in MPAP and pulmonary AT/ET ratio between the two assessments was compared with the expected change in the same gestational period in normal fetuses based on reference curves of MPAP and pulmonary AT/ET ratio constructed in normal fetuses from healthy pregnant women at 19-37 weeks' gestation, encompassing the same gestational age range as the study group (28-37 weeks). RESULTS: Seventy pregnancies with fetal ductus arteriosus constriction were included in the study. After 2 weeks of reduced maternal intake of prostaglandin inhibitors, normalization of mean systolic (change from 1.86 ± 0.34 m/s at diagnosis to 1.38 ± 0.41 m/s; P < 0.001) and diastolic (change from 0.41 ± 0.11 m/s to 0.21 ± 0.065 m/s; P < 0.001) ductal velocities and of mean pulsatility index (change from 1.99 ± 0.20 to 2.55 ± 0.42; P < 0.001) was demonstrated. MPAP decreased between the assessments (change from 66.7 ± 6.90 mmHg at diagnosis to 54.5 ± 6.70 mmHg after 2 weeks; P < 0.001) and mean pulmonary AT/ET ratio increased (change from 0.20 ± 0.06 to 0.33 ± 0.07; P < 0.001). Change in MPAP between diagnosis and after 2 weeks of reduced maternal intake of prostaglandin inhibitors was -12.2 ± 0.30 mmHg, which was 5.3-times higher than that in 305 normal fetuses over 2 weeks during the same gestational period (-2.3 ± 0.19 mmHg) (P < 0.001), and change in pulmonary AT/ET ratio between the two assessments was 0.13 ± 0.08, which was 8.7-times higher than that in normal fetuses in the same gestational period (0.015 ± 0.08) (P < 0.001). CONCLUSIONS: Resolution of fetal ductal constriction is followed by a fall in MPAP and by an increase in pulmonary vascular maturity, to a significantly greater degree than is observed in normal fetuses in the same gestational-age period. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.
Asunto(s)
Conducto Arterial/patología , Feto/irrigación sanguínea , Hipertensión Pulmonar/embriología , Atención Prenatal/métodos , Adulto , Presión Arterial , Velocidad del Flujo Sanguíneo , Constricción Patológica/inducido químicamente , Constricción Patológica/embriología , Conducto Arterial/efectos de los fármacos , Conducto Arterial/embriología , Ecocardiografía Doppler , Femenino , Desarrollo Fetal/efectos de los fármacos , Feto/embriología , Edad Gestacional , Humanos , Hipertensión Pulmonar/etiología , Polifenoles/efectos adversos , Embarazo , Estudios Prospectivos , Antagonistas de Prostaglandina/efectos adversos , Arteria Pulmonar/embriología , Arteria Pulmonar/crecimiento & desarrollo , Arteria Pulmonar/fisiopatología , Flujo Pulsátil , Volumen Sistólico , Ultrasonografía PrenatalRESUMEN
OBJECTIVE: Anti-inflammatory substances that inhibit the synthesis of prostaglandins, such as non-steroidal anti-inflammatory drugs (NSAIDs) and polyphenol-rich foods, can cause constriction of the fetal ductus arteriosus. This study aimed to test the hypothesis that reversal of fetal ductal constriction after maternal restriction of polyphenol-rich foods, in the third trimester of pregnancy, is accompanied by increased plasma levels of prostaglandin E2 (PGE2). METHODS: This was a controlled clinical trial of women with singleton pregnancy ≥ 28 weeks undergoing fetal echocardiography. The intervention group included pregnancies with diagnosis of fetal ductal constriction and not exposed to NSAIDs. The control group consisted of third-trimester normal pregnancies. Both groups answered a food frequency questionnaire to assess the amount of total polyphenols in their diet, underwent Doppler echocardiographic examination and had blood samples collected for analysis of plasma levels of PGE2. Intervention group participants received dietary guidance to restrict the intake of polyphenol-rich foods. The assessments were repeated after 2 weeks in both groups. RESULTS: Forty normal pregnancies were assessed in the control group and 35 with fetal ductal constriction in the intervention group. Mean maternal age (26.6 years) and mean body mass index (30.12 kg/m2 ) were similar between the two groups. Intragroup analysis showed that dietary guidance reduced the median consumption of polyphenols (from 1234.82 to 21.03 mg/day, P < 0.001), increasing significantly the plasma concentration of PGE2 (from 1091.80 to 1136.98 pg/mL, P < 0.05) in the intervention group after 2 weeks. In addition, Doppler echocardiography showed reversal of fetal ductal constriction in the intervention group. No significant changes were observed in the control group. CONCLUSIONS: Dietary intervention for maternal restriction of polyphenol-rich foods in the third trimester of pregnancy is accompanied by increase in plasma levels of PGE2 and reversal of fetal ductal constriction. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.
Asunto(s)
Dieta , Dinoprostona/sangre , Conducto Arterioso Permeable/diagnóstico por imagen , Polifenoles/administración & dosificación , Adulto , Velocidad del Flujo Sanguíneo , Estudios de Casos y Controles , Conducto Arterioso Permeable/sangre , Conducto Arterioso Permeable/fisiopatología , Femenino , Humanos , Embarazo , Tercer Trimestre del Embarazo , Ultrasonografía PrenatalRESUMEN
Digital pathology is becoming technically possible to implement for routine pathology work. At our institution, we have been using digital pathology for second opinion intraoperative consultations for over 10 years. Herein, we describe our experience in converting to a digital pathology platform for primary pathology diagnosis. We implemented an incremental rollout for digital pathology on subspecialty benches, beginning with cases that contained small amounts of tissue (biopsy specimens). We successfully scanned over 40,000 slides through our digital pathology system. Several lessons (both challenges and opportunities) were learned through this implementation. A successful conversion to digital pathology requires pre-imaging adjustments, integrated software and post-imaging evaluations.
Asunto(s)
Diagnóstico por Imagen/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Patología Clínica/métodos , Sistemas de Información Radiológica , Telepatología/métodos , Estudios de Factibilidad , HumanosRESUMEN
OBJECTIVES: To compare the distribution of human leucocyte antigen (HLA) class I and II alleles in patients with erosive hand osteoarthritis (EHOA) to that of patients with non-erosive hand OA (non-EHOA) and in healthy Italian Bone Marrow Donors (IBMDs), in order to evaluate possible immunogenetic associations with EHOA. In the EHOA group we also sought possible associations between HLA alleles and disease severity. METHODS: Ninety-four patients with EHOA (82 women, 12 men; mean age 61.4 ± 8.45 years) and 37 with non-EHOA (28 women, nine men; mean age 59.21 ± 9.07 years) were studied. Disease severity was measured by the number of clinically active joints (NCAJ) and by the radiographic score (RS) using the Kallman scale. HLA typing was undertaken for A, B, C, and DRB1 loci; HLA-DRB1* genotyping was determined using polymerase chain reaction (PCR) with sequence-specific primers. Frequencies were compared with those of the healthy IBMDs. RESULTS: The alleles found more frequently in EHOA patients than in non-EHOA patients and healthy controls were: A23, A26, and A29; B38, B44, and HLA DRB1*01 and *07. The RS was more severe in the EHOA compared to the non-EHOA group (63.60 ± 23.14 vs. 34.34 ± 20.24, p < 0.001). Within the EHOA group, HLA-DRB1*07 was associated with a higher RS (67.36 ± 23 vs. 64.5 ± 18.5, p = 0.029). CONCLUSION: In this study of North Italian patients affected with EHOA, the HLA-DRB1*07 allele was found to be associated with both the development and greater severity of the disease.
Asunto(s)
Articulaciones de la Mano/fisiopatología , Fenómenos Inmunogenéticos/genética , Fenómenos Inmunogenéticos/fisiología , Osteoartritis/etnología , Osteoartritis/genética , Anciano , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes/genética , Antígenos HLA-DR/genética , Cadenas HLA-DRB1 , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase II/genética , Humanos , Italia , Masculino , Persona de Mediana Edad , Osteoartritis/fisiopatología , Índice de Severidad de la EnfermedadRESUMEN
BACKGROUND AND AIM: Elevated serum phosphate and calcium-phosphate levels play an important role in the pathogenesis of vascular calcifications in uraemic patients and appear to be associated with increased cardiovascular mortality. We aimed to evaluate the effects of a partial replacement of food protein with a low-phosphorus and low-potassium whey protein concentrate on phosphate levels of dialysis patients with hyperphosphataemia. METHODS AND RESULTS: Twenty-seven patients undergoing chronic haemodialysis were studied for a 3-month period. In the intervention group (n = 15), food protein were replaced by 30 or 40 g of low-phosphorus and low-potassium protein concentrate aimed at limiting the phosphate intake. In the control group (n = 12) no changes were made to their usual diet. Anthropometric measurements, biochemical markers and dietary interviews were registered at baseline and during the follow-up period. From baseline to the end of the study, in the intervention group, serum phosphate and circulating intact parathyroid hormone levels lessened significantly (8.3 ± 1.2 mg/dL vs 5.7 ± 1.4 mg/dL and 488 ± 205 pg/ml vs 177 ± 100 pg/ml respectively; p < 0.05) with decreasing of phosphate and potassium intake. No significant differences were found in the control group. No significant changes were observed in serum albumin, calcium, potassium, Kt/V, body weight and body composition in both the intervention and control groups. CONCLUSION: Dietary intake of phosphate mainly comes from protein sources, so dietary phosphorus restriction may lead to a protein/energy malnutrition in a dialysis patient. A phosphorus-controlled diet plan including a nutritional substitute resulted in serum phosphate and intact parathyroid hormone decrease without nutritional status modifications in dialysis patients.
Asunto(s)
Proteínas en la Dieta/administración & dosificación , Hiperfosfatemia/dietoterapia , Proteínas de la Leche/administración & dosificación , Fósforo Dietético/administración & dosificación , Diálisis Renal , Dieta , Proteínas en la Dieta/análisis , Femenino , Humanos , Hiperfosfatemia/etiología , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Fosfatos/sangre , Potasio en la Dieta/administración & dosificación , Uremia/terapia , Proteína de Suero de LecheRESUMEN
OBJECTIVES: To asses risk factors for a first thrombotic event in antiphospholipid antibody (aPL) positive carriers and evaluate the efficacy of prophylactic treatments. METHODS: Recruitment criteria were age 18-65 years, no history of thrombosis, positivity for lupus anticoagulant and/or IgG/IgM anticardiolipin antibody (aCL) on > or =2 occasions at least 6 weeks apart. Demographic, laboratory and clinical parameters were collected at enrolment and at the time of the thrombotic event. RESULTS: 370 patients/subjects (mean (SD) age 34 (9.9) years) were analysed retrospectively for a mean (SD) follow-up of 59.3 (45.5) months. Thirty patients (8.1%) developed a first thrombotic event during follow-up. Hypertension and medium/high levels of IgG aCL were identified by multivariate logistic regression analysis as independent risk factors for thrombosis. Thromboprophylaxis during high-risk and long-term periods was significantly protective. CONCLUSIONS: Hypertension or medium/high titres of IgG aCL are risk factors for a first thrombotic event in asymptomatic aPL carriers and primary prophylaxis is protective.
Asunto(s)
Anticuerpos Antifosfolípidos/sangre , Síndrome Antifosfolípido/inmunología , Heterocigoto , Trombosis/etiología , Adolescente , Adulto , Anciano , Anticuerpos Anticardiolipina/sangre , Síndrome Antifosfolípido/genética , Métodos Epidemiológicos , Femenino , Humanos , Hipertensión/complicaciones , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , Trombosis/inmunología , Trombosis/prevención & control , Adulto JovenRESUMEN
OBJECTIVES: Myocardial tissue Doppler (MTD) is a technique for the measurement of myocardial velocities in systole and diastole. This study evaluates the use of MTD in the assessment of cardiac diastolic function in fetuses with intrauterine growth restriction (IUGR) with placental insufficiency and in appropriate-for-gestational age (AGA) fetuses with hypertensive mothers. METHODS: This study included 14 IUGR fetuses with placental insufficiency (Group 1), 13 AGA fetuses with hypertensive mothers (Group 2), and 29 AGA fetuses with healthy mothers (Group 3). Patients with other diseases were excluded. All fetuses had a gestational age of at least 25 weeks. MTD assessment was performed with the sample volume placed at the basal segment of the left ventricular side wall (LV), the interventricular septum (IVS) and the right ventricular free wall (RV). E'/A' ratios were calculated for each location. Mitral and tricuspid flows were assessed by conventional spectral pulsed Doppler. RESULTS: Significant differences were found between groups for E'/A' at the IVS (P < 0.001) and LV (P = 0.009), with a higher mean (+/- SD) value in Group 1 (IVS: 0.92 +/- 0.28; LV: 0.85 +/- 0.19) than in Groups 2 (IVS: 0.62 +/- 0.09; LV: 0.68 +/- 0.14) and 3 (IVS: 0.71 +/- 0.14; LV: 0.69 +/- 0.15). In the RV, there was no statistically significant difference in the E'/A' ratio (P = 0.2). No differences were observed for mitral and tricuspid flow velocities and ratios. CONCLUSIONS: Using MTD, the ratios between early and late diastolic myocardial velocities are higher in IUGR fetuses than in AGA fetuses at the IVS and the LV, regardless of the presence of maternal hypertension. MTD may be more sensitive than atrioventricular spectral Doppler for the detection of ventricular diastolic dysfunction in IUGR fetuses.
Asunto(s)
Retardo del Crecimiento Fetal/fisiopatología , Corazón Fetal/fisiopatología , Insuficiencia Placentaria/fisiopatología , Volumen Sistólico/fisiología , Adulto , Análisis de Varianza , Velocidad del Flujo Sanguíneo/fisiología , Estudios Transversales , Diástole/fisiología , Ecocardiografía Doppler de Pulso/métodos , Femenino , Retardo del Crecimiento Fetal/etiología , Corazón Fetal/diagnóstico por imagen , Humanos , Contracción Miocárdica/fisiología , Embarazo , Complicaciones Cardiovasculares del Embarazo/fisiopatología , Función Ventricular/fisiologíaRESUMEN
OBJECTIVE: To test the hypothesis that, in diabetic pregnancies, left atrial shortening fraction (LASF) is decreased in fetuses with myocardial hypertrophy, compared to those without hypertrophy and to fetuses of non-diabetic mothers. METHODS: Fetal echocardiography was performed in women with pre-existing or gestational diabetes and in non-diabetic controls between 25 weeks' gestation and term. LASF was calculated using the formula: (end-systolic diameter-end-diastolic diameter)/end-systolic diameter, and data were compared between diabetic women with and without fetal myocardial hypertrophy and controls. RESULTS: The study population comprised 53 diabetic women and 45 controls. Out of the 53 fetuses of diabetic women, 14 had myocardial hypertrophy and 39 had normal septal thickness. Gestational age at the time of examination did not differ significantly between the control group and the two diabetic subgroups (P = 0.57). Fetuses with myocardial hypertrophy presented a mean ( +/- SD) LASF of 0.32 +/- 0.11, those without myocardial hypertrophy 0.46 +/- 0.12, and those of normal mothers 0.53 +/- 0.09 (P < 0.001). A significant inverse linear correlation was observed between LASF and septal thickness (r = - 0.51, P < 0.001). CONCLUSIONS: In diabetic pregnancies, LASF is lower in fetuses with myocardial hypertrophy than it is in those without hypertrophy and in fetuses of non-diabetic women, suggesting that LASF could be a useful alternative parameter in the assessment of fetal diastolic function.
Asunto(s)
Cardiomegalia/fisiopatología , Diabetes Mellitus/fisiopatología , Corazón Fetal/fisiopatología , Atrios Cardíacos/fisiopatología , Contracción Miocárdica , Embarazo en Diabéticas , Disfunción Ventricular Izquierda/fisiopatología , Cardiomegalia/diagnóstico por imagen , Estudios de Casos y Controles , Estudios Transversales , Diabetes Mellitus/diagnóstico por imagen , Ecocardiografía , Femenino , Enfermedades Fetales/diagnóstico por imagen , Enfermedades Fetales/fisiopatología , Corazón Fetal/diagnóstico por imagen , Atrios Cardíacos/diagnóstico por imagen , Humanos , Embarazo , Ultrasonografía Prenatal , Disfunción Ventricular Izquierda/diagnóstico por imagenRESUMEN
INCIDENCE: Five hundred and sixty patients began renal replacement therapy in 2006, giving an incidence of 117.51 pmp; in 2007 there were 579 new patients, for an incidence rate of 120.01 pmp. Analysis of the incidence between 1998 and 2007 for both raw and age-standardized data (based on the 2001 census) shows a slow, gradual increase that is statistically significant. Most of the patients were between 55 and 85 years old; the modal class for males was between 65 and 70, and between 75 and 80 for females. The median age of the population beginning replacement therapy is clearly over 65 years old. The year 2000 was particularly significant because the incidence of new patients undergoing renal replacement therapy over the age of 75 definitively exceeded that of the next younger class (65-74 years old), a trend that remained constant until 2007. In 2006 and 2007, males account for 64.4% and 66.4%, respectively, of new patients, a proportion that is constant over the years. The greater incidence of males is also to be found across the other age groups and tends to be even more noticeable in the oldest age class. Incidence by province is highly variable, however, there is a constant trend within provinces during these years, since the incidence in some provinces is lower than the regional average and higher in others. After adjusting for age, there are no significant differences in the incidence between provinces: the age structure of the population accounts for the variability of the incidence of terminal uremia across the Veneto provinces. The conditions most responsible for renal insufficiency requiring replacement therapy are vascular diseases, diabetes and nephropathies of unknown origin. Although diabetic and vascular nephropathies are subject to wide fluctuations, they remain stable over the years, whereas the frequency of nephropathy of unknown origin appears to be on the rise. The first treatment for most of the patients is hemodialysis. In 2006, 436 patients (78%) were given extracorporeal dialysis as first treatment, compared to 122 patients (22%) who were given peritoneal dialysis and 2 (0.35%) who received live-donor kidney transplant. In 2007 the situation was very similar, with 435 patients treated with extracorporeal dialysis, 142 with peritoneal dialysis and 1 by a live-donor transplant. The proportion between patients treated with hemodialysis and peritoneal dialysis was constant from 1998 to 2007. The choice between hemodialysis or peritoneal dialysis as the initial treatment modality depends on many factors, ranging from clinical indications to cultural attitudes at the facility to individual patient preferences. Logistic regression of the factors influencing the choice of dialysis treatment shows that peritoneal dialysis is offered primarily to patients between the ages of 45 and 65 who do not have an underlying systemic or nephropathy of unknown origin and who do not have any comorbidities. This confirms the positive selection made with regard to these patients, widely described in the literature. Initial treatment by transplant is an exceptional event: starting from 2003, it was used in only 1 or 2 patients per year. Seventy-two percent of patients starting replacement therapy present with at least one comorbidity. Thirty-six percent of patients also present with more than one associated disease. The RVDT has been gathering data on the vascular access used for new dialysis patients since 2006. Roughly 43% of patients start treatment with an arteriovenous fistula, 38% with a temporary catheter, less than 1% with a prosthesis, 9% with a tunneled catheter, and 10% with a peritoneal catheter. Logistic regression was used to evaluate what role age, primary nephropathies and comorbidities present at the start of treatment play in determining the choice of a temporary catheter. The logistic model estimates a 29% probability of starting treatment with a temporary access. This probability decreases if the patient suffers from a familiar or hereditary nephropathy but increases if the patient has secondary glomerulonephritis or is affected by a group of various diseases (multiple myeloma or other pathologies) or if the patient suffers at the same time from cardiac insufficiency or an infection. The estimated probability of starting hemodialysis with a mature fistula is 40%, but this figure diminishes significantly in female patients, if the patient has secondary glomerulonephritis, cardiac insufficiency or infections. PREVALENCE: As of December 31, 2006, there were 4,071 patients being treated with extracorporeal or peritoneal dialysis or by kidney transplant, leading to a prevalence of 852.82 patients pmp; as of December 31, 2007, there were 4,200 patients treated, with a corresponding prevalence of 869.14 pmp. The breakdown in prevalence by age group shows that the increase in prevalence is highly significant in the top two age classes, namely, between 65 and 75 years of age and over 75, while remaining negligible in the other classes. Between 1998 and 2007, the prevalence increased by 40% in patients over 75 and increased by 20% in the class of 65-to-75 year olds. The elderly contribute a greater weight in the renal replacement therapy population, reflected in the gradual increase of the median age of the prevalent population from 1998 to 2007. During 2006 and 2007, males made up 63.99% and 64.36% of the patients, respectively. This relative frequency mirrors the findings for incidence and is constant over the years. The distribution of primary diseases is very different in the prevalent population compared to findings in the incident patients. Primary glomerulonephritis, at fourth place among incident patients, is the most frequent disease in the prevalent population (although there is a clearly downward trend over the years). The percentages of diabetes and vascular disease, on the other hand, are lower compared to what is observed in the incident population. The prevalence expressed by treatment modality pmp increased for all three types. In analyzing the annual percentage rise in prevalence, using 1998 as the baseline, the most significant figure regards transplant patients, whose prevalence increased by over 60% between 1998 and 2007. Prevalence of hemodialysis patients rose moderately by only slightly over 10%. Peritoneal dialysis shows a rather linear increase, similar to the transplant trend. Our study used longitudinal regression models to analyze factors predictive of a patient starting and continuing to undergo the same type of treatment over the years. The results show that a patient has a greater probability of being treated with hemodialysis based on several primary nephropathies, when aged > 45, and in the presence of the main comorbidities. The predictive factors for peritoneal dialysis mentioned earlier have a diametrically opposed role. The presence of comorbidities (except high blood pressure), the type of nephropathy, and age > 65 lead to a lower probability of receiving a transplant. We analyzed peritoneal dialysis failures - defined as changing over to extracorporeal dialysis for any reason (clinical, psychological or social) - and the cumulative incidence of failure, taking into account the two competing outcomes of transplant and death. The only variable associated with peritoneal dialysis failure was the presence of infections. Older patients, patients with peripheral vascular disease, and those with neoplasia are less frequently taken off peritoneal dialysis to receive a transplant, an event occurring more frequently, however, in patients with hypertension. Death is dependent on age, on the presence of peripheral vascular disease and is less frequent in hypertensives. As is the case for peritoneal dialysis, the natural history of kidney transplant can have two competing outcomes: return to dialysis and death. The risk factors associated with return to dialysis are the presence of peripheral vascular disease, hypertension and infections; risk factors associated with death include age, the presence of cerebral vascular disease and neoplasia. From 1998 to 2007, the prevalence of hepatitis C virus-antibody-positive patients decreased by almost one third. The number of antigen-positive hepatitis B patients is declining slowly, but the levels remain in any case very low. The association between the two infections is disappearing: already at very low levels in 1998, that figure was halved by 2007. MORTALITY AND SURVIVAL: The mortality of uremic patients on renal replacement therapy was calculated both as a cumulative incidence, expressed as the number of deaths over patients at risk (alive at the beginning of the study year) and as a mortality rate, expressed as the number of deaths per patients/year. The figure was constant over the years, at around 10%. The mortality of males was no different from that of females; this finding differs from what is observed in the general population where male mortality is markedly higher than that of females. The mortality rate is dependent on the age group of the patient at start of treatment and shows an upward trend that is growing exponentially. The mortality rate in hemodialysis patients remained stable at 15% between 2000 and 2007, while the mortality rate in peritoneal dialysis patients gradually decreased down to 13%. The mortality rate for transplant patients was low and constant, at under 2%. The trend for the various causes of death is stable over the years and shows that the main cause of death is cardiac, accounting for between 30% and 35%, while mortality due to vascular, neoplastic, infection or cachexia-related causes are all roughly at the same rate, between 10% and 15%. (ABSTRACT TRUNCATED)
Asunto(s)
Trasplante de Riñón/estadística & datos numéricos , Sistema de Registros , Diálisis Renal/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Italia , Masculino , Persona de Mediana Edad , Insuficiencia Renal/mortalidad , Insuficiencia Renal/terapia , Tasa de Supervivencia , Factores de TiempoRESUMEN
This is a case report of a woman who showed headache, weakness, upper-limb edema and a generalized convulsive seizure after chronic ingestion of liquorice. She was taking oral contraceptives which can predispose to liquorice toxicity. Plasma potassium, aldosterone, renin activity and albumin were below the normal level. The abdominal echography and computerized tomography scan demonstrated a perihepatic and perisplenic thin liquid layer with liquid collection in the pelvis. The bioelectrical impedance suggested a hyperhydration state. After stopping the liquorice, the laboratory and bioelectrical values normalized and clinical upper-limb edema and the liquid in the abdomen disappeared in a few days.
Asunto(s)
Edema/patología , Glycyrrhiza/química , Hipopotasemia/patología , Extractos Vegetales/efectos adversos , Abdomen , Adulto , Edema/inducido químicamente , Femenino , Humanos , Hipertensión/fisiopatología , Hipopotasemia/inducido químicamente , Extractos Vegetales/química , Tomografía Computarizada por Rayos X , Ultrasonografía , Agua/metabolismoRESUMEN
Anti-inflammatory property of polyphenols and their effect on the metabolism of prostaglandins is not established in healthy humans. This study aimed to evaluate the effect of polyphenol supplementation in plasma levels of prostaglandin E2 and other markers of inflammation and oxidative stress in women using contraceptives. In this randomized double-blind clinical trial, women aged 25-35 years were selected. Participants received capsules containing polyphenols or placebo, to be consumed for fifteen days. From 40 women randomized, 28 completed the study. Control group showed a significant increase in the levels of PGE2 (p=0.01) while the polyphenols group showed no change in these levels (p=0.79). There was an increase in hs-CRP (p<0.01) and F2-isoprostane (p=0.04) in the control group. The GSSG to GSH ratio significantly reduced in the polyphenols group (p=0.02). Supplementation with polyphenol capsules inhibited the increase in markers of inflammation and oxidative stress in women of childbearing age using combined hormonal contraceptives.
Asunto(s)
Antiinflamatorios no Esteroideos/administración & dosificación , Estrés Oxidativo/efectos de los fármacos , Polifenoles/administración & dosificación , Prostaglandinas E/sangre , Adulto , Antiinflamatorios no Esteroideos/farmacología , Cápsulas , Anticoncepción , Suplementos Dietéticos , Método Doble Ciego , F2-Isoprostanos/sangre , Femenino , Humanos , Polifenoles/farmacología , ReproducciónRESUMEN
Salmonella enterica is a common cause of gastrointestinal illness in Italy. S. Typhimurium accounts for approximately 40% of isolates, and most of these strains belong to the phage type DT104. We describe the investigation of an outbreak of S. Typhimurium DT104A, a subtype never observed before in Italy, which occurred in Rome during spring 2004.We conducted a matched case control study between 24 July and 9 September 2004. Controls were matched for age and area of residence. Each case had between one and four controls. Odds of exposure to potential risk factors and vehicles for the outbreak were compared between cases and controls. A multivariate analysis was conducted to estimate adjusted Odds Ratios.Sixty-three cases of S. Typhimurium DT 104A infection with onset between 1 April and 5 May 2004 were identified. Sixty-one were residents of Rome and two were residents of a neighbouring region. Twenty-six cases (43%) were enrolled in the study. Their median age was 7.5 years. Fourteen of 26 cases and 16 of 62 controls had eaten pork salami (OR= 25.5; 95% CI 1.6- 416.8). No food samples were available for testing. In northern Italy, two months prior to the outbreak, the veterinary surveillance system identified the first isolation of S. Typhimurium DT104A in a pig isolate. Both human and pig isolates showed indistinguishable PFGE patterns. It was not possible to trace the pig after the sample was taken at slaughter. The epidemiological evidence on the implication of pork salami in this outbreak suggests that pork products can also be a vehicle for salmonella in Italy and underlines the importance of good manufacturing practices for ready-to-eat foods. This investigation highlights the value of laboratory-based surveillance in identifying community-wide outbreaks of uncommon pathogens. It also underlines the need to improve surveillance timeliness, for promptly detecting outbreaks, undergoing field investigation, and implementing control measures. Moreover, our study shows the usefulness of integrated human and animal surveillance in tracing the possible source of infection.
Asunto(s)
Brotes de Enfermedades/estadística & datos numéricos , Contaminación de Alimentos/estadística & datos numéricos , Productos de la Carne/microbiología , Productos de la Carne/estadística & datos numéricos , Intoxicación Alimentaria por Salmonella/epidemiología , Salmonella typhimurium/aislamiento & purificación , Adolescente , Adulto , Anciano , Niño , Preescolar , Comercio , Femenino , Congelación , Vacaciones y Feriados , Humanos , Incidencia , Lactante , Italia/epidemiología , Masculino , Persona de Mediana Edad , Vigilancia de la Población , Medición de Riesgo/métodos , Factores de Riesgo , Intoxicación Alimentaria por Salmonella/microbiologíaRESUMEN
The antioxidant profile of extracts from solid olive residue (SOR) of c.v. Coratina, a cultivar widely diffused in the south of Italy, using both cell-free and cell-based experimental models, was investigated. A total hydroalcoholic extract (polyphenols content 19.7%) and a purified extract (Oleaselecttrade mark) (polyphenols content 35.1%) were tested for their ability to quench the stable free radical DPPH, the peroxyl radicals (ORAC assay), by monitoring the loss in fluorescence of R-phycoerythrin induced by the peroxyl radical generator AAPH and their ability to inhibit the cumene hydroperoxide-induced lysis of rat red blood cells (RBC). The total hydroalcoholic extract showed IC(50) 26.96+/-1.53 microg/ml in the DPPH assay, that 10 microg/ml were equivalent to 2.11+/-0.12 microg/ml Trolox (ORAC assay) and IC(50) 1.7+/-0.20 microg/ml in the RBC hemolysis. The Oleaselect extract was 4 to 5 folds more active than the hydroalcoholic extract in all the experimental models, with IC(50) values of 7.36+/-0.38 microg/ml in the DPPH test and of 0.38+/-0.03 microg/ml in RBC; the antioxidant activity in the ORAC assay was slightly greater than that of Trolox (10 microg/ml equivalent to 11.45+/-0.40 microg/ml). The scavenging effect of the extract in the ORAC assay was compared to that of verbascoside (the main polyphenol component) and of caffeic acid (the basic constituent of verbascoside): the results indicate that caffeic acid (10 microg/ml equivalent to 35.70+/-2.95 microg/ml Trolox) is more potent than verbascoside (10 microg/ml equivalent to 15.42+/-1.21 microg/ml Trolox) in entrapping peroxyl radicals. Finally the antioxidant activity of the Oleaselect extract was confirmed in human umbilical endothelial cells (EC) exposed to the site-specific peroxyl radical inducer AAPH, where a massive lipid peroxidation process (marker the fluorescence probe BODIPY) takes place, paralleled by a marked loss of cell viability (calcein assay). The purified extract (1-20 microg/ml) pre-incubated with EC for 1 h dose-dependently inhibited both the lipid-peroxidation damage and cell death. Taking into account the total polyphenol content, these results clearly indicate a greater antioxidant activity for the purified extract, due to a cooperative antioxidant interaction among its polyphenol constituents.
Asunto(s)
Antioxidantes/farmacología , Flavonoides/química , Flavonoides/farmacología , Olea/química , Fenoles/química , Fenoles/farmacología , Extractos Vegetales/farmacología , Amidinas/química , Animales , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo/antagonistas & inhibidores , Línea Celular , Células Cultivadas , Relación Dosis-Respuesta a Droga , Células Endoteliales/citología , Células Endoteliales/metabolismo , Radicales Libres , Hemólisis/efectos de los fármacos , Humanos , Hidrazinas/antagonistas & inhibidores , Masculino , Picratos , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Polifenoles , Ratas , Ratas WistarRESUMEN
UNLABELLED: ESSENTIALS: Thrombosis is a major comorbidity in patients with chronic obstructive pulmonary disease (COPD). Roflumilast is a selective phosphodiesterase type-4 (PDE4) inhibitor approved for treatment of severe COPD. PDE4 blockade by roflumilast inhibits prothrombotic functions of neutrophils and monocytes. PDE4 inhibitors may reduce thrombotic risk in COPD as well as in other vascular diseases. BACKGROUND: Roflumilast, an oral selective phosphodiesterase type 4 inhibitor, is approved for the treatment of severe chronic obstructive pulmonary disease (COPD). A recent meta-analysis of trials on COPD revealed that treatment with roflumilast was associated with a significant reduction in the rate of major cardiovascular events. The mechanisms of this effect remain unknown. OBJECTIVES: We tested the hypothesis that roflumilast N-oxide (RNO), the active metabolite of roflumilast, curbs the molecular mechanisms required for leukocyte-platelet (PLT) interactions and prevents the prothrombotic functions of polymorphonuclear leukocytes (PMNs) and monocytes (MNs). METHODS: Using well-characterized in vitro models, we analysed the effects of RNO on: (i) PMN adhesiveness; (ii) the release of neutrophil extracellular traps (NETs); and (iii) tissue factor expression in MNs. Key biochemical events underlying the inhibitory effects of RNO were defined. RESULTS AND CONCLUSIONS: In PMNs, RNO prevented phosphoinositide 3-kinase (PI3K)-dependent phosphorylation of Akt on Ser473, and Src family kinase (SFK)-mediated Pyk2 phosphorylation on Tyr579-580, while inducing protein kinase A-mediated phosphorylation of C-terminal Src kinase, the major negative regulator of SFKs. Modulation of these signaling pathways by RNO resulted in a significant impairment of PMN adhesion to activated PLTs or human umbilical vein endothelial cells, mainly mediated by inhibition of the adhesive function of Mac-1. Moreover RNO curbed SFK/PI3K-mediated NET release by PMNs adherent on fibrinogen-coated surfaces. In MNs interacting with activated PLTs, RNO curbed PI3K-mediated expression of tissue factor. The efficacy of RNO was significantly potentiated by formoterol, a long acting ß-adrenergic receptor agonist. This study reveals novel antithrombotic activities by which roflumilast may exert protective effects against cardiovascular comorbodities in COPD.
Asunto(s)
Aminopiridinas/farmacología , Benzamidas/farmacología , Plaquetas/efectos de los fármacos , Leucocitos/efectos de los fármacos , Monocitos/citología , Neutrófilos/citología , Trombosis/sangre , Animales , Enfermedades Cardiovasculares/prevención & control , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 4/metabolismo , Ciclopropanos/farmacología , Trampas Extracelulares , Fibrinógeno/química , Humanos , Antígeno de Macrófago-1/genética , Ratones , Microscopía Confocal , Monocitos/efectos de los fármacos , Neutrófilos/efectos de los fármacos , Selectina-P/genética , Selectina-P/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de Fosfodiesterasa 4/farmacología , Fosforilación , Adhesividad Plaquetaria/efectos de los fármacos , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Riesgo , Tromboplastina/metabolismoRESUMEN
OBJECTIVE: To evaluate plasma atrial natriuretic factor (ANF) behavior in hypertensive patients with either insulin-dependent (type I) or non-insulin-dependent (type II) diabetes. RESEARCH DESIGN AND METHODS: Plasma ANF levels were measured in euglycemic normotensive patients (n = 18) and hypertensive patients (n = 18), in diabetic normotensive patients (type I diabetes, n = 12; type II diabetes, n = 12), and in diabetic hypertensive patients (type I diabetes, n = 12; type II diabetes, n = 22). In all groups, plasma ANF levels were determined at the end of a normal NaCl diet period (120 mmol NaCl per day for 10 days) in both the supine and the upright positions. RESULTS: Plasma ANF levels were significantly higher (P < 0.05) in hypertensive euglycemic patients (supine vs. upright: 13.4 +/- 6.7 vs. 8.5 +/- 4.3 fmol/ml) than in normotensive type I diabetic patients (supine vs. upright: 8.6 +/- 2.2 vs. 5.9 +/- 2.9 fmol/ml) but not in euglycemic normotensive subjects (supine vs. upright: 11.4 +/- 5.1 vs. 7.6 +/- 5.8 fmol/ml) and normotensive type II diabetic patients (supine vs. upright: 10.1 +/- 4.1 vs. 7.9 +/- 4.1 fmol/ml). Moreover, in the normotensive groups plasma ANF levels did not significantly differ among euglycemic type I and type II diabetic patients. However, the highest levels of plasma ANF were observed in hypertensive type II diabetic patients (supine vs. upright: 16.9 +/- 7.4 fmol/ml [P < 0.01 vs. euglycemic normotensive subjects, P < 0.0001 vs. normotensive type I diabetic patients, P < 0.01 vs. hypertensive type I diabetic patients and normotensive type II diabetic patients] vs. 11.6 +/- 2.9 fmol/ml [P < 0.005 vs. normotensive type I diabetic patients, P < 0.01 vs. hypertensive type I diabetic patients]). On the contrary, plasma ANF levels were higher (P < 0.05) in hypertensive type I diabetic patients (supine vs. upright: 10.8 +/- 1.9 vs. 6.4 +/- 2.2 fmol/ml) compared with normotensive type I diabetic patients, but not with any other patient group. A significant correlation between supine ANF and insulin levels was found in both type II diabetic (r = 0.457; P < 0.05) and nondiabetic hypertensive patients (r = 0.716; P < 0.0001). CONCLUSIONS: These findings indicate that circulating ANF levels are markedly elevated in type II diabetic patients affected by essential hypertension. On the contrary, plasma ANF levels are in the range of normality in normotensive type I and type II diabetic patients.
Asunto(s)
Factor Natriurético Atrial/sangre , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 2/sangre , Hipertensión/sangre , Adulto , Análisis de Varianza , Glucemia/metabolismo , Presión Sanguínea , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/orina , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/orina , Ayuno , Femenino , Fructosamina , Hexosaminas/sangre , Humanos , Hipertensión/complicaciones , Hipertensión/orina , Insulina/sangre , Masculino , Persona de Mediana Edad , Postura , Potasio/sangre , Potasio/orina , Valores de Referencia , Sodio/sangre , Sodio/orinaRESUMEN
OBJECTIVE: To evaluate the effects of captopril on circulating catecholamine levels in NIDDM patients and the possible relationship between captopril-related changes in circulating catecholamine levels and insulin sensitivity. RESEARCH DESIGN AND METHODS: Fourteen nonobese normotensive NIDDM men (aged 44.5 +/- 5.1 years) underwent a 2-h euglycemic-hyperinsulinemic clamp (40 mU.m-2.min-1). Baseline evaluation of insulin sensitivity was followed by the random assignment of each patient to either captopril or placebo treatment, according to a crossover double-blind design. Euglycemic-hyperinsulinemic clamp studies were then repeated for all patients after both placebo and captopril treatments. Plasma norepinephrine (NE) and epinephrine (E) levels were assessed before, during, and after each clamp. RESULTS: Resulting data showed that plasma catecholamine levels increased during baseline euglycemic-hyperinsulinemic clamp (NE: +23.6% time 0 vs. time 120 min, P < 0.05; E: +24.8% time 0 vs. time 120 min, P < 0.05). Captopril treatment significantly increased total glucose uptake (from 19.0 +/- 9.0 to 26.8 +/- 10.1 mmol.kg-1.min-1, P < 0.05) and reduced baseline plasma NE (P < 0.001) and E (P < 0.05) levels. However, the magnitude of the NE (+25.7% time 0 vs. time 120 min, P < 0.001) and E (+27.2% time 0 vs. time 120 min, P < 0.05) increments during euglycemic hyperinsulinemia were not affected by the drug. Percentage changes in the ratio of total body glucose uptake to circulating insulin levels and corresponding decrements of baseline plasma E levels after captopril therapy were negatively correlated (r = -0.57, P < 0.05). CONCLUSIONS: The reduction of circulating catecholamines could contribute, at least in part, to the captopril-related amelioration of insulin sensitivity.
Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Captopril/uso terapéutico , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/fisiopatología , Epinefrina/sangre , Norepinefrina/sangre , Adulto , Glucemia/metabolismo , Estudios Cruzados , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Técnica de Clampeo de la Glucosa , Humanos , Infusiones Intravenosas , Insulina/administración & dosificación , Insulina/sangre , Insulina/farmacología , MasculinoRESUMEN
To evaluate the influence of salt sensitivity on the blood pressure response to oral indomethacin treatment, we studied 35 hospitalized essential hypertensive patients (24 men and 11 women, aged from 40 to 55 years). During a normal NaCl intake (120 mmol Na+ per day), patients were assigned to receive in a randomized double-blind fashion either 200 mg indomethacin (25 patients) or placebo (10 patients) for 5 days. Two weeks after the interruption of indomethacin treatment, during which the normal NaCl intake was continued, salt sensitivity was assessed by giving each patient a high (220 mmol Na+ per day for 10 days) and then a low (20 mmol Na+ per day for 10 days) NaCl diet. Blood pressure changes were evaluated, and the measurement taken at the end of the 2 weeks under normal sodium intake was considered baseline blood pressure. Patients were classified as salt sensitive when a diastolic blood pressure change of 10 mm Hg or more occurred after both low and high periods of sodium intake. In salt-resistant patients treated with indomethacin (n = 12, nine men and three women, mean age 50.5 +/- 3.7 years), neither blood pressure (systolic blood pressure from 150.8 +/- 11.2 to 154.6 +/- 9.3 mm Hg, NS; diastolic blood pressure from 99.3 +/- 2.1 to 101.1 +/- 4.4 mm Hg, NS) nor the urinary Na+ excretion (from 108.1 +/- 20.9 to 97.9 +/- 9.1 mmol/24 hr, NS) was significantly affected by the drug.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Presión Sanguínea/efectos de los fármacos , Inhibidores de la Ciclooxigenasa/farmacología , Hipertensión/fisiopatología , Indometacina/farmacología , Cloruro de Sodio/farmacología , Adulto , Factor Natriurético Atrial/sangre , Diástole , Método Doble Ciego , Resistencia a Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , SístoleRESUMEN
Structural alterations of small arteries in patients with essential hypertension are characterized by inward eutrophic remodeling. However, small arteries in patients with secondary hypertension, as well as in experimental models of hypertension with high circulating renin, are characterized by inward hypertrophic remodeling, which is characterized by smooth muscle cell hypertrophy in animal models. The aim of our study was to determine whether remodeling of subcutaneous small arteries in patients with secondary forms of hypertension is associated with smooth muscle cell hypertrophy and/or alterations in the elastic modulus of the vessel wall. Fifteen patients with renovascular hypertension, 9 with primary aldosteronism, and 13 with essential hypertension and 9 normotensive subjects were included in the study. A biopsy of subcutaneous fat was taken from all subjects. Small arteries were dissected, and morphology was determined on a micromyograph. Unbiased estimates of cell volume and number were made in fixed material. From the resting tension-internal circumference relation of the small arteries, the incremental elastic modulus was calculated and plotted as a function of wall stress. Blood pressure was greater in patients with essential hypertension, renovascular hypertension, or primary aldosteronism than in normotensive subjects, but no significant difference was observed among the 3 groups of hypertensive patients. The media/lumen ratio, the medial cross-sectional area, and the smooth muscle cell volume were significantly greater in patients with renovascular hypertension than in normotensive subjects and patients with essential hypertension. No difference in cell number or in the elastic properties was observed among the 4 groups of subjects. In conclusion, our data demonstrate for the first time that a pronounced activation of the renin-angiotensin-aldosterone system is associated with vascular smooth muscle cell hypertrophy in human hypertension in a manner similar to that found in animal models.
Asunto(s)
Arterias/patología , Hipertensión Renovascular/patología , Arterias/fisiopatología , Presión Sanguínea , Tamaño de la Célula , Elasticidad , Humanos , Hipertensión Renovascular/fisiopatología , Piel/irrigación sanguínea , Resistencia VascularRESUMEN
Endothelin-1 (ET-1) is a potent vasoactive and mitogenic peptide produced by the vascular endothelium. In this study, we evaluated whether insulin stimulates ET-1 secretion by human endothelial cells derived from umbilical cord veins and by human permanent endothelial hybrid cells Ea.hy 926. Moreover, to provide evidence that insulin may stimulate ET-1 secretion in vivo, plasma ET-1 levels were evaluated in 7 type II diabetic normotensive males (mean age, 54.3 +/- 4.0 yr) during 2-h hyperinsulinemic euglycemic clamps (287 pmol insulin/m2.min-1) as well as in 12 obese hypertensive males (mean age, 44.2 +/- 4.6 yr) before and after a 12-week period of caloric restriction. Our results showed that insulin stimulated ET-1 release from cultured endothelial cells in a dose-dependent fashion. ET-1 release persisted for 24 h and was also observed at physiological insulin concentrations (10(-9) mol/L). The insulin-induced ET-1 secretion was inhibited by genistein, a tyrosine kinase inhibitor, and by cycloheximide, a protein synthesis inhibitor, suggesting that it requires de novo protein synthesis rather than ET-1 release from intracellular stores. In the in vivo experiments, plasma ET-1 levels rapidly increased during euglycemic hyperinsulinemic clamps (from 0.76 +/- 0.18 pg/mL at time zero to 1.65 +/- 0.21 pg/mL at 60 min; P < 0.05) and persisted elevated until the end of insulin infusion (1.37 +/- 0.37 pg/mL at 120 min; P < 0.05 vs. time zero). In obese hypertensives, plasma ET-1 levels significantly decreased after 12 weeks of caloric restriction (from 0.85 +/- 0.51 to 0.48 +/- 0.28 pg/mL; P < 0.04). The decrease in body weight induced by caloric restriction was accompanied by a significant reduction in fasting insulin levels (from 167.2 +/- 94.0 to 98.9 +/- 44.9 pmol/L; P < 0.05) which correlated with the reduction in plasma ET-1 levels (r = 0.78; P < 0.003). In conclusion, our data show that insulin stimulates both in vitro and in vivo ET-1 secretion. Such interaction could play a significant role in the development of atherosclerotic lesions in hyperinsulinemic conditions.
Asunto(s)
Endotelinas/metabolismo , Endotelio Vascular/metabolismo , Insulina/farmacología , Adulto , Línea Celular , Relación Dosis-Respuesta a Droga , Endotelinas/sangre , Endotelio Vascular/citología , Glucosa/farmacología , Humanos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/farmacologíaRESUMEN
We evaluated the effects on cardiovascular structure of the angiotensin-converting enzyme (ACE) inhibitor enalapril and of the angiotensin II receptor blocker losartan, administered either at hypotensive or nonhypotensive dosage in spontaneously hypertensive rats (SHR). SHR were treated from ages 4 to 12 weeks with low-dose (1 mg x kg(-1) x d(-1)) enalapril, low-dose (0.5 mg x kg(-1) x d(-1)) losartan, high-dose (25 mg x kg(-1) x d(-1)) enalapril, or high-dose (15 mg x kg(-1) x d(-1)) losartan. Untreated WKY and SHR were also studied. Rats were killed at 13 weeks of age, and the heart was weighed. Mesenteric small arteries were dissected and mounted on a micromyograph for determination of media thickness and lumen diameter. In fixed arteries, cell volume, number of cells per segment length, and number of cell layers were measured using the unbiased "disector" method. Systolic blood pressure was significantly reduced by the high doses of both drugs, but the hypotensive effect was greater with enalapril than with losartan (P<0.05). In the high-dose enalapril and losartan groups, there were similar reductions in relative left ventricular mass, media/lumen ratio, and number of cell layers of resistance arteries; however, there were no differences in the cell volume or number of cells per segment length of resistance arteries. Low-dose enalapril did not affect systolic blood pressure or any of the structural parameters. The results show that the hypotensive effects of both losartan and enalapril were associated with outward remodeling of resistance arteries at the cellular level. The effect of losartan on resistance artery structure was equal to that of enalapril, despite the smaller hypotensive effect.