Recepcion de balastos para lamparas de vapor de mercurio

La gran utilización de artefactos y equipos con lámparas de vapor de mercurio, destinados a la iluminación pública, originó la necesidad de evaluar las características del balasto, accesorio fundamental de este tipo de fuentes de luz. Los ensayos que señala el autor de este trabajo son aptos, por la rapidez de ejecución y representatividad, para facilitar las tareas de recepción y control. A través de los mismos se pueden obtener valores comparativos, cuando se utiliza una lámpara de referencia, y valores uniformes y reproducibles en el caso de utilizar, además, el balasto patrón correspondiente.This paper details some of the most important testing procedures in ballast for mercury gas-discharge lamps. The more important conditions affecting lamps and ballast testing are described. This procedure was selected for his celerity and for his représentâtivi- ty for the reception and control of the lamps ballasts. Comparative values can be obtained using a reference lamp, and for uniform and reproductible values the use of a reference ballast in necesary

Hypothyroidism and nephrotic syndrome: why, when and how to treat

Hypothyroidism, characterised by low/normal free thyroxine (FT4) and free tri-iodothyronine (FT3) with elevated thyroid-stimulating hormone (TSH), is a well-known complication of nephrotic syndrome (NS). This is a common feature of primary and secondary glomerular diseases and comprises loss of protein in the urine and increased urinary excretion of thyroid hormones and thyroxine-binding globulin. With a normal thyroid reserve, this scenario is associated with the development of subclinical hypothyroidism, with a slight increase in TSH and normal free fractions. However, with a low thyroid reserve the transition toward overt hypothyroidism is almost inevitable, affecting morbidity and mortality. As T4 replacement is a cheap and well-established treatment to achieve a stable hormone status in different types of thyroid deficiency, it is essential to recognise and appropriately treat this condition. In this article we summarise the evidence on this nephro-endocrine disorder in humans and focus on diagnostic and therapeutic strategies

Pharmacological effects of raas blockade in ischemic nephropathy

Background: The management of ischemic nephropathy due to atherosclerotic renal artery stenosis has become increasingly conservative in the modern era, with current guidelines recommending optimized medical therapy as the initial step. The doubts raised by the recently published trials of revascularization strategies have led to a renewed focus on pharmacological strategies promoting blood pressure control and renal protection. It is essential to further elucidate the pathophysiological mechanisms underlying hypoperfusion induced renal microvascular dysfunction with subsequent tissue injury and fibrogenesis. The role of renin angiotensin aldosterone system as a mediator of the main pathophysiological consequences of ischemic nephropathy is well known. However, more recent experimental evidence on the adrenergic system and intrarenal tubular feedback mechanisms has stimulated new interest towards a multi-target therapeutic approach. Methods: This review focuses on the pharmacology of the principle therapeutic drug classes currently used in the treatment of atherosclerotic renal artery stenosis with an analysis of their metabolic aspects and use in clinical practice based on evidence from clinical trials. Results and Conclusions: An optimal pharmacologic approach is crucial for a successful prevention of renal injury and cardiovascular events in this high-risk population. Antihypertensive treatment should include renin angiotensin aldosterone system blockade medication not only for their antihypertensive properties, but especially for those cardio and renoprotectiv

Serum uric acid as a marker of microvascular damage in systemic sclerosis patients

Background: Microvascular damage of skin and internal organs is a hallmark of systemic sclerosis (SSc). Serum uric acid (UA) represents a marker of inflammation and endothelial dysfunction. The aims of this study were to evaluate the correlation between serum UA and intrarenal arterial stiffness evaluated by Doppler ultrasound in SSc patients with normal renal function. We also evaluated the correlation between serum UA and other clinical variables of the disease. Methods: Forty-five SSc patients underwent clinical assessment, Doppler ultrasound of intrarenal arteries with evaluation of resistive index (RI), pulsatile index (PI), and systolic/diastolic ratio (S/D), echocardiography with systolic pulmonary artery pressure (PAPs), baseline pulmonary function tests, and nailfold videocapillaroscopy (NVC). In all patients serum UA was measured. Results: The serum UA showed a significant positive correlation with sCr (r = 0.33, p < 0.0001) and PAPs (r = 0.38, p < 0.01) > and negative correlation with CKD-EPI (r = -0.35, p < 0.01). The mean value of serum UA increased with severity of NVC damage. Using this cut-off value of 4.7 mg/dl, the mean value of Doppler indices of intrarenal stiffness is significantly different (p < 0.05) in SSc patients with low normal or high normal serum UA. Conclusions: Serum UA concentration is higher in patients with high microvascular damage than in patients with low microvascular damage. These preliminary data must be confirmed in large prospective studies

Parkinson's disease: autoimmunity and neuroinflammation

Parkinson's disease is a neurodegenerative disease that causes the death of dopaminergic neurons in the substantia nigra. The resulting dopamine deficiency in the basal ganglia leads to a movement disorder that is characterized by classical parkinsonian motor symptoms. Parkinson's disease is recognized as the most common neurodegenerative disorder after Alzheimer's disease. PD ethiopathogenesis remains to be elucidated and has been connected to genetic, environmental and immunologic conditions. The past decade has provided evidence for a significant role of the immune system in PD pathogenesis, either through inflammation or an autoimmune response. Several autoantibodies directed at antigens associated with PD pathogenesis have been identified in PD patients. This immune activation may be the cause of, rather than a response to, the observed neuronal loss. Parkinsonian motor symptoms include bradykinesia, muscular rigidity and resting tremor. The non-motor features include olfactory dysfunction, cognitive impairment, psychiatric symptoms and autonomic dysfunction. Microscopically, the specific degeneration of dopaminergic neurons in the substantia nigra and the presence of Lewy bodies, which are brain deposits containing a substantial amount of α-synuclein, have been recognized. The progression of Parkinson's disease is characterized by a worsening of motor features; however, as the disease progresses, there is an emergence of complications related to long-term symptomatic treatment. The available therapies for Parkinson's disease only treat the symptoms of the disease. A major goal of Parkinson's disease research is the development of disease-modifying drugs that slow or stop the neurodegenerative process. Drugs that enhance the intracerebral dopamine concentrations or stimulate dopamine receptors remain the mainstay treatment for motor symptoms. Immunomodulatory therapeutic strategies aiming to attenuate PD neurodegeneration have become an attractive option and warrant further investigation

Mediciones de calidad de aire en La Plata, Berisso y Ensenada

Este trabajo de carácter multidisciplinario constituye un aporte para el mejor conocimiento de la calidad del aire de la zona urbana e industrial correspondiente a La Plata, Berisso y Ensenada. Se intenta correlacionar los resultados obtenidos mediante el empleo de distintas técnicas, tales como corrosión atmosférica sobre acero, liqúenes como bioindicadores y medición de dióxido de azufre por métodos óptico y químico. Se hace un comentario de la corrosión atmosférica sobre el acero, y los efectos que produce. Se presentan las ventajas e inconvenientes de la utilización de bioindicadores de contaminantes del aire, en particular los liqúenes. Se describen las metodologías empleadas en cada técnica y se citan los equipos e instrumentos utilizados. Finalmente se brindan los resultados preliminares obtenidos en cada caso hasta el presente y un comentario de los mismos.Tema: Hábitat y ambiente.Asociación Argentina de Energía Sola

Mediciones de calidad de aire en La Plata, Berisso y Ensenada

Este trabajo de carácter multidisciplinario constituye un aporte para el mejor conocimiento de la calidad del aire de la zona urbana e industrial correspondiente a La Plata, Berisso y Ensenada. Se intenta correlacionar los resultados obtenidos mediante el empleo de distintas técnicas, tales como corrosión atmosférica sobre acero, liqúenes como bioindicadores y medición de dióxido de azufre por métodos óptico y químico. Se hace un comentario de la corrosión atmosférica sobre el acero, y los efectos que produce. Se presentan las ventajas e inconvenientes de la utilización de bioindicadores de contaminantes del aire, en particular los liqúenes. Se describen las metodologías empleadas en cada técnica y se citan los equipos e instrumentos utilizados. Finalmente se brindan los resultados preliminares obtenidos en cada caso hasta el presente y un comentario de los mismos.Tema: Hábitat y ambiente.Asociación Argentina de Energía Sola

Mediciones de calidad de aire en La Plata, Berisso y Ensenada

Este trabajo de carácter multidisciplinario constituye un aporte para el mejor conocimiento de la calidad del aire de la zona urbana e industrial correspondiente a La Plata, Berisso y Ensenada. Se intenta correlacionar los resultados obtenidos mediante el empleo de distintas técnicas, tales como corrosión atmosférica sobre acero, liqúenes como bioindicadores y medición de dióxido de azufre por métodos óptico y químico. Se hace un comentario de la corrosión atmosférica sobre el acero, y los efectos que produce. Se presentan las ventajas e inconvenientes de la utilización de bioindicadores de contaminantes del aire, en particular los liqúenes. Se describen las metodologías empleadas en cada técnica y se citan los equipos e instrumentos utilizados. Finalmente se brindan los resultados preliminares obtenidos en cada caso hasta el presente y un comentario de los mismos.Tema: Hábitat y ambiente.Asociación Argentina de Energía Sola

Left ventricular mass and intrarenal arterial stiffness as early diagnostic markers in cardiorenal syndrome type 5 due to systemic sclerosis

Background: Cardiorenal syndrome type 5 (CRS-5) includes a group of conditions characterized by a simultaneous involvement of the heart and kidney in the course of a systemic disease. Systemic sclerosis (SSc) is frequently involved in the etiology of acute and chronic CRS-5 among connective tissue diseases. In SSc patients, left ventricular mass (LVM) can be used as a marker of nutritional status and fibrosis, while altered intrarenal hemodynamic parameters are suggestive of early kidney involvement. Methods: Forty-two consecutive patients with a diagnosis of SSc without cardiac and/or renal impairment were enrolled to assess whether cardiac muscle mass can be related to arterial stiffness. Thirty subjects matched for age and sex were also enrolled as healthy controls (HC). All patients performed echocardiography and renal ultrasound. Results: Doppler indices of intrarenal stiffness and echocardiographic indices of LVM were significantly increased in SSc patients compared to HC. A positive correlation exists between LVM/body surface area and pulsatile index (p < 0.05, r = 0.36), resistive index (p < 0.05, r = 0.33) and systolic/diastolic ratio (p < 0.05, r = 0.38). Doppler indices of intrarenal stiffness and LVM indices were significantly higher in SSc patients with digital ulcers than in SSc patients without a digital ulcer history. Conclusions: SSc is characterized by the presence of microvascular and multiorgan injury. An early cardiac and renal impairment is very common. LVM and intrarenal arterial stiffness can be considered as early markers of CRS onset. The clinical use of these markers permits a prompt identification of organ damage. An early diagnosis allows the appropriate setting of pharmacological management, by slowing disease progression