RESUMEN
We summarise a Cochrane review of qualitative evidence that explored parents' views and practices around routine childhood vaccination, and provide implications for research and practice that are relevant to the South African (SA) context. Many public health interventions to encourage vaccination are informed by an assumption that vaccine hesitancy is due to a lack of knowledge or irrational forms of thinking. The findings from this review suggest that childhood vaccination views and practices are complex social processes that are shaped by multiple factors and carry a variety of meanings. As such, we suggest that biomedical approaches must be supplemented by more nuanced and sociopolitically informed strategies for enhancing and sustaining childhood vaccination practices in SA.
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Cuidadores , Padres , Humanos , Sudáfrica , Vacunación , Salud Pública , Conocimientos, Actitudes y Práctica en Salud , Aceptación de la Atención de SaludRESUMEN
The role of an influenza vaccine is to minimise illness and death. Vaccines provide good protection against influenza strains and significantly reduce time off work. However, the recommendation for use depends on the efficacy, effectiveness and safety of the vaccines. We highlight a Cochrane review that sought to determine the efficacy, effectiveness and safety of seasonal influenza vaccines in healthy children, and provide implications for practice for vaccination of children. The findings suggest that influenza vaccines play a key role in reducing serious morbidity and mortality among children. There were few data available to provide firm conclusions on adverse events. Vaccinating against influenza not only reduces its incidence among children, but also extends these benefits to the unvaccinated population, such as the elderly. In light of the many direct and indirect benefits of vaccinating children aged 2 - 16 years, there is a need to provide access to influenza vaccines to all eligible South African children.
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Vacunas contra la Influenza/administración & dosificación , Gripe Humana/prevención & control , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Gripe Humana/epidemiología , Masculino , Sudáfrica/epidemiologíaRESUMEN
COVID-19 spreads easily between people who are in close contact, or through coughs and sneezes. As the number of cases continues to increase, healthcare workers (HCWs) are notably at risk as a result of frequency of contact with suspected cases or infected people. Use of infection prevention and control (IPC) strategies by HCWs is therefore important. We summarise the evidence from a rapid Cochrane qualitative evidence synthesis by Houghton et al. on barriers and facilitators to HCWs' adherence to IPC guidelines for respiratory infectious diseases.
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Infecciones por Coronavirus , Personal de Salud , Control de Infecciones , Pandemias , Neumonía Viral , Betacoronavirus , COVID-19 , Humanos , SARS-CoV-2RESUMEN
COVID-19 spreads easily between people who are in close contact, or through coughs and sneezes. As the number of cases continues to increase, healthcare workers (HCWs) are notably at risk as a result of frequency of contact with suspected cases or infected people. Use of infection prevention and control (IPC) strategies by HCWs is therefore important. We summarise the evidence from a rapid Cochrane qualitative evidence synthesis by Houghton et al. on barriers and facilitators to HCWs' adherence to IPC guidelines for respiratory infectious diseases
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COVID-19 , Enfermedades Transmisibles/prevención & control , Adhesión a Directriz , Personal de Salud , Equipo de Protección Personal , SudáfricaRESUMEN
Vaccine hesitancy is an emerging problem in South Africa (SA), which threatens to erode the country's immunisation achievements. Communication interventions may be an effective strategy for addressing vaccine hesitancy. We highlight a Cochrane review of qualitative evidence that explored parents' views and experiences of communication regarding childhood vaccinations, and provide implications for practice that are relevant to the SA context. The findings suggest that healthcare providers (HCPs) play a central role in childhood vaccination attitudes and decision-making. Therefore, capacitating HCPs to promote vaccination with confidence is key to effective communication to address vaccine hesitancy in SA.
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Cuidadores , Conocimientos, Actitudes y Práctica en Salud , Niño , Humanos , Padres , Aceptación de la Atención de Salud , Sudáfrica , VacunaciónRESUMEN
BACKGROUND: Acute kidney injury (AKI) following cardiac surgery is a frequent complication and several risk factors increasing its incidence have already been characterized. This study evaluates the influence of preoperative increased serum uric acid (SUA) levels in comparison with other known risk factors on the incidence of AKI following cardiac surgery. METHODS: During a period of 5 month, 247 patients underwent elective coronary artery bypass grafting, valve replacement/ repair or combined bypass and valve surgery. Datas were prospectively analyzed. Primary endpoint was the incidence of AKI as defined by the AKI criteria comparing patients with preoperative serum uric acid (SUA) levels below versus above the median. Multivariate logistic regression analysis was used to identify independent predictors of postoperative AKI. RESULTS: Thirty (12.1%) of the 247 patients developed postoperative AKI, 24 of 30 (80%) had preoperative SUA- levels above the median (≥373 µmol/l) (OR: 4.680, CI 95% 1.840; 11.904, p = 0.001). In the multivariate analysis SUA levels above the median (OR: 5.497, CI 95% 1.772; 17.054, p = 0.003), cardiopulmonary bypass (CPB) time > 90 min (OR: 4.595, CI 95% 1.587; 13.305, p = 0.005), cardiopulmonary bypass (CPB) > 30 kg/m2 (OR: 3.208, CI 95% 1.202; 8.562; p = 0.02), and preoperative elevated serum-creatinine levels (OR: 1.015, CI 95% 1.001; 1.029, p = 0.04) were independently associated with postoperative AKI. CONCLUSIONS: Serum uric acid is an independent risk marker for AKI after cardiac surgery. From all evaluated factors it showed the highest odds ratio.
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Lesión Renal Aguda/sangre , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Complicaciones Posoperatorias/sangre , Cuidados Preoperatorios , Ácido Úrico/sangre , Lesión Renal Aguda/diagnóstico , Anciano , Biomarcadores/sangre , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Valor Predictivo de las Pruebas , Cuidados Preoperatorios/métodos , Estudios Prospectivos , Factores de RiesgoRESUMEN
OBJECTIVE: Paediatric laboratory reference intervals used in Africa and Asia may be derived from historical intervals of predominantly Caucasian infants in Europe or North America. These intervals may therefore not be compatible with the range of normality for developing country populations. We aimed to compare haematology and biochemistry parameters in healthy South African infants with local laboratory reference intervals. METHODS: We compared the baseline haematology and biochemistry results of 634 (316 male and 318 female) HIV-unexposed infants, aged 3-6 months, living in a rural area of the Western Cape Province, South Africa, against laboratory reference intervals supplied by the South African National Health Laboratory Services (NHLS). We calculated the percentage of observed values out of bound (in terms of lower and upper limits) compared to laboratory reference intervals. RESULTS: Of the 634 healthy infants screened, 316 (49.84%) were male and 318 (50.16%) female. A majority (91.05%) had platelet counts above the laboratory reference interval upper limit (350 × 109 cells/l), while over half, 54.85% and 56.98% had mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH) values below the lower limits of 77.0-105.0 fl and 26.0-34.0 pg, respectively. A small proportion were outside the reference limits for haematocrit, namely 15.71% below and 7.14% above the normal limits of 0.31-0.38 l/l. For male and female infants, 33.65% and 18.04% of alkaline phosphatase (ALP) values and 7.01% and 14.56% of alanine transaminase (ALT) values were above the upper limits, respectively. For male infants, 10.83% of gamma-glutamyl transferase (GGT) values, and for female infants, 31.11% of GGT values were below the lower limits of 12 U/l for males and 15 U/l for females. We observed no significant deviations (>10% out of bound) from NHLS reference intervals in the remaining haematology and biochemistry parameters measured. CONCLUSIONS: Haematology and biochemistry parameters in apparently healthy South African infants deviate frequently from national laboratory reference intervals, including abnormalities consistent with subclinical hypochromic microcytic anaemia. It is important that clinical laboratory reference intervals for children are derived locally, rather than being adopted from Caucasian norms in developed countries, because clinical trials of vaccines, drugs and diagnostics are increasingly conducted in sub-Saharan Africa.
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Química Clínica/normas , Hematología/normas , Bienestar del Lactante , Estándares de Referencia , Recuento de Células Sanguíneas/normas , Femenino , Humanos , Lactante , Masculino , Vigilancia en Salud Pública , Valores de Referencia , SudáfricaRESUMEN
BACKGROUND: The Xpert MTB/RIF test shortens the time to microbiological confirmation of pulmonary tuberculosis (TB) under research conditions. OBJECTIVE: To evaluate the field impact of Xpert MTB/RIF rollout on TB diagnostic yield and time to treatment in a South African (SA) community. METHODS: We compared TB investigation outcomes for 6-month calendar periods before and after Xpert MTB/RIF rollout in a semi-rural area of SA. The proportion of adult patients who tested positive by sputum smear microscopy, liquid culture or Xpert MTB/RIF and the proportion of positive sputum smear, liquid culture or Xpert MTB/RIF tests were compared. Secondary outcomes included time to laboratory diagnosis and treatment initiation. Data were collected from the National Health Laboratory Service database and from the Western Cape Provincial Department of Health TB register. RESULTS: Regional rollout of Xpert MTB/RIF testing occurred in 2013. Of the 15 629 patients investigated in the post-rollout period, 7.9% tested positive on GeneXpert, compared with 6.4% of the 10 741 investigated in the pre-rollout period who tested positive by sputum smear microscopy (p<0.001). Median laboratory processing time was <1 day for Xpert MTB/RIF (interquartile range (IQR) 0 - 1) compared with 1 day (IQR 0 - 16) for sputum smear microscopy (p=0.001). The median time to TB treatment initiation was 4 days (IQR 2 - 8) after rollout compared with 5 days (IQR 2 - 14) before (p=0.001). CONCLUSIONS: Patients investigated for suspected pulmonary TB were more likely to be diagnosed after rollout of Xpert MTB/RIF testing, although the benefit to diagnostic yield was modest, and Xpert MTB/RIF testing was associated with a marginal improvement in time to treatment initiation.
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SETTING: South Africa. OBJECTIVE: To evaluate the long-term effectiveness of infant modified vaccinia Ankara virus-expressing antigen 85A (MVA85A) vaccination against tuberculosis (TB). DESIGN: We analysed data from a double-blind randomised placebo-controlled Phase 2b MVA85A infant TB vaccine trial (2009-2012), with extended post-trial follow-up (2012-2014). Isoniazid preventive therapy (IPT) was provided by public health services according to national guidelines. The primary outcome was curative treatment for TB disease. Survival analysis and Poisson regression were used for study analysis. RESULTS: Total follow-up was 10 351 person-years of observation (pyo). Median follow-up age was 4.8 years (interquartile range 4.4-5.2). There were 328 (12%) TB cases. TB disease incidence was 3.2/100 pyo (95%CI 2.8-3.5) overall, and respectively 3.3 (95%CI 2.9-3.9) and 3.0 (95%CI 2.6-3.5)/100 pyo in the MVA85A vaccine and placebo arms. A total of 304 children (11%) received IPT, with respectively 880 and 9471 pyo among IPT and non-IPT recipients. There were 23 (7.6%) TB cases among 304 IPT recipients vs. 305 (12.9%) among 2374 non-IPT recipients (P = 0.008). IPT effectiveness was 85% (95%CI 76-91). CONCLUSION: Extended follow-up confirms no long-term effectiveness of infant MVA85A vaccination, but a six-fold reduction in TB risk can be attributed to IPT. National TB programmes in high TB burden countries should ensure optimal implementation of IPT for eligible children.
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Antituberculosos/administración & dosificación , Isoniazida/administración & dosificación , Vacunas contra la Tuberculosis/administración & dosificación , Tuberculosis/prevención & control , Preescolar , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Lactante , Masculino , Distribución de Poisson , Sudáfrica/epidemiología , Análisis de Supervivencia , Resultado del Tratamiento , Tuberculosis/epidemiología , Vacunación , Vacunas de ADNRESUMEN
Hyponatremia is the most common form of electrolyte disorder in the emergency room. The symptoms are unspecific and include nausea, dizziness and often falls. Typical symptoms of severe hypernatremia are vomiting, cerebral seizures, somnolence and even coma. The specific initial laboratory diagnostics include measurement of serum electrolytes, serum glucose, serum and urine osmolarity and sodium in urine. The main aim of the clinical examination is to estimate the volume status. If a patient has hypovolemia an infusion of isotonic sodium chloride solution (0.9 %) is the method of choice. If the patient is euvolemic the syndrome of inappropriate antidiuretic hormone secretion (SIADH) or (neurotropic) drugs might be the cause. In these cases the primary measure is restriction of fluid intake. As a rapid correction of sodium levels can lead to pontine myelinolysis, the increase in sodium concentration must not be less than 10 mmol/l within the first 24 h and 18 mmol/l within the first 48 h. Clinical symptoms of hyperkalemia include neurological (e.g. muscle weakness, paresis, hyperreflexia, cramps and dysesthesia), gastrointestinal (e.g. nausea, vomiting and diarrhea) and cardiac symptoms (e.g. dysrhythmia and conductance disorders). Calcium injection stabilizes cardiac rhythm disorders immediately. For a rapid drop in potassium by shifting the potassium to the intracellular space, administration of glucose with insulin and high-dose inhalative administration of betamimetics can be used. Potassium elimination is achieved by infusion of isotonic sodium choride (0.9 %) with i.v. administration of furosemide, ion exchange resins and hemodialysis.
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Cuidados Críticos/métodos , Fluidoterapia/métodos , Hiperpotasemia/diagnóstico , Hiperpotasemia/terapia , Hiponatremia/diagnóstico , Hiponatremia/terapia , Servicio de Urgencia en Hospital/organización & administración , HumanosRESUMEN
Secondary hypertension affects only 5-10 % of hypertensive patients. Screening is expensive and time-consuming and should be performed only in patients for whom there is a high clinical suspicion of secondary hypertension. Clinical signs of secondary forms of hypertension are new-onset hypertension in patients without other risk factors (i.e., family history, obesity, etc.), sudden increase of blood pressure (BP) in a previously stable patient, increased BP in prepubertal children, resistant hypertension, and severe hypertension or hypertensive emergencies. In adults, renal parenchymal and vascular diseases as well as obstructive sleep apnea are the most common causes of secondary hypertension. Medication-induced hypertension and non-adherence to medication have to be ruled out. Of the endocrine causes associated with hypertension, primary aldosteronism is the most common. Other endocrine causes of hypertension such as thyroid disease (hypo- or hyperthyroidism), hypercortisolism (Cushing's syndrome), hyperparathyroidism, and pheochromocytoma are rare. Monogenetic forms of hypertension are mostly of tubular origin and associated with alterations in mineralocorticoid handling or signaling. Rare causes of hypertension also include inflammatory vascular disease. Acute forms of vasculitis may present as "malignant" hypertension with associated thrombotic microangiopathy and organ damage/failure. It is important to diagnose these rare forms of hypertension in order to prevent acute organ damage in these patients or unnecessary invasive treatment strategies.
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Neoplasias de las Glándulas Suprarrenales/complicaciones , Hipertensión/etiología , Enfermedades Renales/complicaciones , Obesidad/complicaciones , Feocromocitoma/complicaciones , Enfermedades Vasculares/complicaciones , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Diagnóstico Diferencial , Humanos , Hipertensión/diagnóstico , Enfermedades Renales/diagnóstico , Obesidad/diagnóstico , Feocromocitoma/diagnóstico , Enfermedades Raras/diagnóstico , Enfermedades Raras/etiología , Enfermedades Vasculares/diagnósticoRESUMEN
Chronic kidney disease (CKD) is highly prevalent. Independent from the underlying disease, measures capable of decreasing the progression of CKD have been identified. Lowering of blood pressure and proteinuria are most important. As the potential risk of aggressive blood pressure-lowering strategies has become obvious, the current very low blood pressure goals are doubted. Thus, patients have to be treated individually taking into consideration each patient's preexisting cardiovascular damage and the risk of CKD progression. Additional modifiable risk factors are blood glucose in diabetic patients, lipids, anemia, uric acid, vitamin D, protein intake, and smoking.
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Antihipertensivos/uso terapéutico , Hipertensión/complicaciones , Hipertensión/tratamiento farmacológico , Fallo Renal Crónico/tratamiento farmacológico , Fallo Renal Crónico/etiología , Humanos , Fallo Renal Crónico/diagnósticoAsunto(s)
Condrocalcinosis/tratamiento farmacológico , Supresores de la Gota/uso terapéutico , Gota/tratamiento farmacológico , Hiperuricemia/tratamiento farmacológico , Alopurinol/efectos adversos , Alopurinol/uso terapéutico , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Condrocalcinosis/diagnóstico , Comorbilidad , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Febuxostat , Gota/diagnóstico , Adhesión a Directriz , Humanos , Hipertrofia Ventricular Izquierda/diagnóstico , Hipertrofia Ventricular Izquierda/tratamiento farmacológico , Hiperuricemia/diagnóstico , Proteína Antagonista del Receptor de Interleucina 1/efectos adversos , Proteína Antagonista del Receptor de Interleucina 1/uso terapéutico , Fallo Renal Crónico/tratamiento farmacológico , Tiazoles/efectos adversos , Tiazoles/uso terapéutico , Xantina Oxidasa/antagonistas & inhibidoresRESUMEN
The biological processes responsible for somatic cell senescence contribute to organ aging and progression of chronic diseases, and this may contribute to kidney transplant outcomes. We examined the effect of pre-existing donor aging on the performance of kidney transplants, comparing mouse kidney isografts and allografts from old versus young donors. Before transplantation, old kidneys were histologically normal, but displayed an increased expression of senescence marker p16(INK4a). Old allografts at day 7 showed a more rapid emergence of epithelial changes and a further increase in the expression of p16(INK4a). Similar but much milder changes occurred in old isografts. These changes were absent in young allografts at day 7, but emerged by day 21. The expression of p16(INK4a) remained low in young kidney allografts at day 7, but increased with severe rejection at day 21. Isografts from young donors showed no epithelial changes and no increase in p16(INK4a). The measurements of the alloimmune response-infiltrate, cytology, expression of perforin, granzyme B, IFN-gamma and MHC-were not increased in old allografts. Thus, old donor kidneys display abnormal parenchymal susceptibility to transplant stresses and enhanced induction of senescence marker p16(INK4a), but were not more immunogenic. These data are compatible with a key role of somatic cell senescence mechanisms in kidney transplant outcomes by contributing to donor aging, being accelerated by transplant stresses, and imposing limits on the capacity of the tissue to proliferate.
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Envejecimiento/inmunología , Senescencia Celular , Supervivencia de Injerto , Trasplante de Riñón , Animales , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Inmunohistoquímica , Riñón/metabolismo , Riñón/patología , Trasplante de Riñón/inmunología , Masculino , Ratones , Ratones Endogámicos CBA , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Trasplante HomólogoRESUMEN
La hipertrofia ventricular izquierda es una de las principales lesiones de órganos diana relacionadas con la hipertensión arterial. Dicha hipertrofia influye de forma importante en el pronóstico cardiovascular del paciente hipertenso. Las técnicas más utilizadas para identificar la hipertrofia ventricular son la electrocardiografía y los métodos de imagen. Las principales ventajas de la electrocardiografía son su disponibilidad generalizada a un coste muy bajo, su reproductibilidad y la independencia del observador. Su principal debilidad es su baja sensibilidad. El método de imagen más ampliamente utilizado para valorar la masa ventricular izquierda es la ecocardiografía. No obstante, la ecocardiografía presenta una variabilidad inter e intraobservador bastante grande, sobrevalora de forma regular la masa ventricular en los corazones hipertrofiados y se basa en gran medida en suposiciones geométricas. Su principal ventaja es la posibilidad de valorar el llenado ventricular y la relajación diastólica. La hipertrofia ventricular izquierda puede modificarse mediante la administración de fármacos antihipertensivos, siendo los más eficaces los bloqueantes de los receptores de angiotensina y los inhibidores de la enzima de conversión de angiotensina. La reducción de la masa ventricular izquierda se asocia con una disminución del riesgo cardiovascular. La regresión de la hipertrofia debería definirse como uno de los objetivos de la terapia antihipertensiva, de forma adicional e independiente al control de la presión arterial
Left ventricular hypertrophy is one of the main lesions of the target organs related with high blood pressure. This hypertrophy has an important effect on the cardiovascular prognosis of the hypertense patient. The techniques used most to identify ventricular hypertrophy are the electrocardiogram and imaging methods. The primary advantages of the electrocardiogram are its generalized availability at a very low cost, its reproducibility and the observer independence. Its main weakness is its low sensitivity. The most widely used imaging method to evaluate left ventricular mass is the echocardiogram. However, the echocardiogram has a very large inter and intra-rater variability, commonly overestimates the ventricular mass in hypertrophied hearts and is largely based on geometric suppositions. Its main advantage is the possibility of evaluating ventricular filling and diastolic relaxation. Left ventricular hypertrophy may be modified through the administration of antihypertensive drugs, the most effective ones being angiotensin receptor blockers and angiotensin converting enzyme inhibitors. Reduction of left ventricular mass is associated with a decrease of cardiovascular risk. Regression of hypertrophy should be defined as one of the goals of antihypertensive therapy, as an addition and independently to the control of blood pressure
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Humanos , Hipertrofia Ventricular Izquierda/diagnóstico , Hipertrofia Ventricular Izquierda/fisiopatología , Electrocardiografía , Antihipertensivos/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/farmacocinéticaAsunto(s)
Encefalopatías/etiología , Cardiopatías/etiología , Hipertensión/complicaciones , Enfermedades Renales/etiología , Albuminuria , Encefalopatías/patología , Creatinina/sangre , Ecocardiografía , Femenino , Tasa de Filtración Glomerular , Cardiopatías/patología , Humanos , Hipertensión/patología , Enfermedades Renales/patología , Masculino , Especificidad de Órganos , Retina/patología , Factores de RiesgoRESUMEN
BACKGROUND: Impaired baroreflex sensitivity (BRS) is a negative predictive factor of mortality in cardiovascular disease. Aldosterone has been shown to decrease BRS in humans and animal models. However, the mode of aldosterone action, whether genomic or nongenomic has not been determined. Therefore, we conducted a clinical study to examine whether BRS, as measured by the phenylephrine method, is impaired in humans by aldosterone by a nongenomic mechanism. METHODS: In a randomised, double-blinded, fourfold cross-over trial in 16 healthy male volunteers, BRS was tested 15 minutes after initiation of a continuous infusion of aldosterone (3 microg/minute) or placebo. 6 hours earlier, this period was preceded by an injection of either canrenoate (400 mg) or placebo. RESULTS: BRS was 34.6 +/- 4.7 ms/mm Hg in the placebo/placebo period. It was significantly blunted in the placebo/aldosterone (25.5 +/- 1.8 ms/mm Hg) as well as in the canrenoate/placebo (24.0 +/- 1.5 ms/mm Hg) and the canrenoate/aldosterone (25.4 +/- 2.5 ms/mm Hg) periods. CONCLUSION: These data suggest that the decreased BRS caused by aldosterone is due to a rapid, thus presumably nongenomic mechanism, as these effects occur in a time frame that excludes genomic aldosterone effects at large. The mineralocorticoid receptor (MR) antagonist canrenoate does not block these effects, but blunts BRS by itself.
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Aldosterona/farmacología , Barorreflejo/efectos de los fármacos , Adulto , Aldosterona/administración & dosificación , Aldosterona/sangre , Presión Sanguínea , Ácido Canrenoico/administración & dosificación , Estudios Cruzados , Método Doble Ciego , Humanos , Cinética , Masculino , Antagonistas de Receptores de Mineralocorticoides/administración & dosificación , PlacebosRESUMEN
BACKGROUND: Angiotensin II type 1 (AT(1)) receptors are well known to mediate angiotensin II (Ang II)-induced pro-atherosclerotic effects. It has been found that hypercholesterolemia influences the expression of AT(1) receptors on vascular smooth muscle cells and that increased density of AT(1) receptors exaggerates the hemodynamic response to Ang II. We analyzed to what extent statins and AT(1) receptor antagonists diminish the vasoconstrictive response to Ang II infusion in hypercholesterolemic patients. METHODS: A total of 24 male patients with LDL cholesterol levels >130 mg/dL were enrolled in a randomized, cross-over study. After baseline evaluation, 12 patients received first cerivastatin (0.3 mg/day) and the other 12 patients initially received candesartan (8 mg/day) for 3 weeks, with subsequent cross-over of the medication for the second 3-week drug period. The vascular response was analyzed by the increase in mean arterial pressure (MAP) and total peripheral resistance (TPR) during infusion of increasing doses of Ang II at baseline and the end of each treatment period. Hemodynamic changes were also compared with those in 24 normocholesterolemic subjects without any therapy. RESULTS: At baseline, Ang II provoked a similar increase of MAP and TPR in patients and control subjects. Treatment with cerivastatin did not affect the response to Ang II compared with baseline. By contrast, treatment with candesartan attenuated significantly the response to Ang II compared with baseline and cerivastatin. CONCLUSIONS: Our hemodynamic data indicate the hypothesis that statins do not reduce the responsiveness to Ang II in resistance arteries of young, mildly hypercholesterolemic patients.
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Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Angiotensina II/metabolismo , Bencimidazoles/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hipercolesterolemia/tratamiento farmacológico , Tetrazoles/uso terapéutico , Resistencia Vascular/efectos de los fármacos , Adolescente , Adulto , Bloqueadores del Receptor Tipo 1 de Angiotensina II/administración & dosificación , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Bencimidazoles/administración & dosificación , Bencimidazoles/farmacología , Biomarcadores/sangre , Compuestos de Bifenilo , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Hipercolesterolemia/sangre , Hipercolesterolemia/fisiopatología , Masculino , Persona de Mediana Edad , Piridinas/uso terapéutico , Índice de Severidad de la Enfermedad , Tetrazoles/administración & dosificación , Tetrazoles/farmacología , Triglicéridos/sangre , Vasoconstrictores/metabolismoRESUMEN
BACKGROUND: Glucocorticosteroids are effective in the treatment of allergic rhinitis, a disease characterized by a variety of symptoms, e.g. rhinorrhea and itching. The time course of symptomatic relief for allergic rhinitis by steroids has not been examined in detail to date, although the onset of steroid action is one of the main discriminations between genomic and nongenomic actions of steroids. We therefore investigated the time course of subjective and objective measures of nasal affection after steroid administration in patients with allergic rhinitis following specific allergen challenge. METHODS: Six female and 18 male volunteers (median age 26 years) with a history of allergic rhinitis but currently free of symptoms were included in this randomized, placebo-controlled, double-blind, three-period crossover study. A single dose of either betamethasone (60 mg), methylprednisolone (400 mg) or placebo was given intravenously, 5 min after intranasal allergen provocation. After 10, 20, 60, 150 and 240 min, nasal itching and nasal obstruction were assessed using a standardized visual analogue scale. In addition, nasal airflow was measured by anterior rhinomanometry. RESULTS: Nasal itching was markedly reduced following either of the two steroids within 10 min after administration of study drug. Itching was depressed by 38% following betamethasone (P<0.05) and by 18% following methylprednisolone (P=0.07) compared with placebo. Nasal airflow and nasal obstruction were not significantly altered by steroids during the first 2 h of the study. However, after 150 min, nasal airflow was 21% rsp. 19% higher after methylprednisolone and betamethasone (P<0.05) compared with placebo. After 240 min, nasal airflow was increased by 20% following betamethasone (P<0.05) and by 19% following methylprednisolone. Nasal obstruction was also beneficially affected by both steroids 150 and 240 min after administration compared with placebo (P<0.05 for both time points following betamethasone). CONCLUSION: This study for the first time shows rapid in vivo effects of external glucocorticosteroids in humans. Itching, a pathophysiologically complex sensation, is favourably influenced by steroids within 10 min, therefore presumably via nongenomic mechanisms. Though no detailed mechanisms can be derived from this study, steroid interaction with receptors in the central nervous system may play an important role in mediating this effect.