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Search Results: 1 - 10 of 23515 matches for " Fernando Lombi "
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"Síndrome complejo de malnutrición e inflamación" en la hemodiálisis crónica "Malnutrition-inflammation complex syndrome" in chronic hemodialysis
Pablo Young,Fernando Lombi,Bárbara C. Finn,Mariano Forrester
Medicina (Buenos Aires) , 2011,
Abstract: La malnutrición calórico-proteica y la inflamación suelen ser condiciones comunes y concurrentes en pacientes con hemodiálisis crónica, asociándose ambas a mal pronóstico. La hiporexia y el hipercatabolismo son características comunes y frecuentes. Se ha sugerido que la primera es secundaria a la inflamación. Si bien la evidencia no es concluyente, se ha acu ado el término síndrome complejo de malnutrición e inflamación para englobar esta situación clínica, independientemente de la causa originaria. Posibles causas de este síndrome incluyen diferentes comorbilidades, estrés oxidativo, pérdida de nutrientes a través de la diálisis, hiporexia, toxinas urémicas, elevación de citoquinas inflamatorias, sobrecarga de volumen, hiperfosfatemia, subdiálisis, entre otros. Se cree que en este síndrome la resistencia a la eritropoyetina, promueve la enfermedad aterosclerótica, disminuyendo la calidad de vida e incrementando el tiempo de internación y la mortalidad. Este síndrome origina un bajo índice de masa corporal, hipocolesterolemia, sarcopenia e hipocreatininemia, e hipohomocisteinemia, paradójicamente incrementando el riesgo cardiovascular. A este fenómeno se lo ha denominado "epidemiología reversa". Por lo tanto, y dentro de ciertos límites, la obesidad, la hipercolesterolemia, el incremento de la creatinina y de la homocisteína jugarían un rol protector, asociándose a mejor pronóstico. No existe consenso sobre cómo determinar la gravedad del síndrome complejo de malnutrición e inflamación, su abordaje y su tratamiento. En este trabajo se discuten varias herramientas diagnósticas y modalidades de tratamiento. El correcto manejo de este cuadro podría disminuir en última instancia la enfermedad cardiovascular, principal causa de óbito en esta población. Protein-energy wasting (PEW) and inflammation are usually common and concurrent conditions in maintenance dialysis patients and associated with poor prognosis. Low appetite and hypercatabolic states are common features. In dialysis patients, the former has been suggested to be secondary to inflammation; however, the evidence is not conclusive. Hence, the term malnutrition-inflammation complex syndrome (MICS) was coined to include this clinical entity, regardless the original causes. Possible causes of MICS include comorbid illnesses, oxidative stress, nutrient loss through dialysis, hyporexia, uremic toxins, decreased clearance of inflammatory cytokines, volume overload, increased blood phosphate and dialysis-related factors. MICS is believed to be the main cause of erythropoietin hypo-responsiveness, cardiova
Injuria renal aguda en la sepsis grave Acute kidney injury in severe sepsis
Hernán Trimarchi,Christian Nozieres,Vicente Cámpolo Girard,Fernando Lombi
Medicina (Buenos Aires) , 2009,
Abstract: La sepsis afecta al 40% de los pacientes críticos, siendo su mortalidad de aproximadamente un 30% en el caso de la sepsis grave, y de 75% con injuria renal aguda, la cual sucede en el 20-51% de los casos. Se realizó un estudio prospectivo, observacional, longitudinal, en 80 pacientes sépticos graves en el lapso de 1 a o para determinar el desarrollo de injuria renal aguda y su relación con la mortalidad; correlacionar antecedentes clínicos y variaciones del laboratorio con la mortalidad; determinar la tasa de mortalidad de la sepsis grave; relacionar óbito y foco séptico primario; evaluar la predictibilidad de mortalidad según niveles de creatinina de ingreso y sus variaciones finales. Se definieron dos grupos: Obito (n = 25) y No-óbito (n = 55). Analizados según la creatinina de ingreso, 39 tenían valores normales de creatinina (10 óbitos) y 41 la presentaban elevada (15 óbitos); según la creatinina de egreso, 48 presentaron creatinina normal y fallecieron 7, mientras que 32 tenían da o renal agudo, de los cuales 18 fallecieron. De los 25 pacientes fallecidos, el 72% presentaron da o renal. De éstos, 7 pacientes vivos y 2 fallecidos requirieron hemodiálisis. El foco primario más frecuente fue el respiratorio (26.4%). El desarrollo de da o renal es un alto predictor de mortalidad en la sepsis, independientemente de los valores iniciales de creatinina. Edad más avanzada, hipertensión arterial, score APACHE más elevado, anemia más grave, hipoalbuminemia, hiperfosfatemia e hiperkalemia se asociaron a mayor mortalidad. La mortalidad global fue 31.3%. La imposibilidad de identificar el foco séptico primario se asoció a mayor mortalidad. El foco respiratorio se relacionó a mayor riesgo de requerir hemodiálisis. Sepsis affects 40% of critically ill patients, with a reported mortality of approximately 30% in severe sepsis, raising to 75% when acute kidney injury ensues, which occurs in about 20-51% of cases. The present study consists on a one-year prospective, observational, longitudinal trial undergone in 80 severe septic patients to determine the risk of development of acute kidney injury and its relationship with mortality; the association of the clinical course and blood parameter variations with mortality; the severe sepsis mortality rate; an eventual correlation between death and septic focus, and to assess mortality predictibility based on initial creatinine levels and final variations. Two groups were defined: Dead (n=25) and Not-dead (n=55). According to creatinine on admission, 39 subjects presented with normal creatinine levels (10 deaths) and 41 pr
Is There a Role for Mammalian Target of Rapamycin Inhibition in Renal Failure due to Mesangioproliferative Nephrotic Syndrome?
Hernán Trimarchi,Mariano Forrester,Fernando Lombi,Vanesa Pomeranz,Romina Iriarte,María Soledad Ra?a,Pablo Young
International Journal of Nephrology , 2012, DOI: 10.1155/2012/427060
Abstract: Primary glomerulonephritis stands as the third most important cause of end-stage renal disease, suggesting that appropriate treatment may not be as effective as intended to be. Moreover, proteinuria, the hallmark of glomerular damage and a prognostic marker of renal damage progression, is frequently resistant to thorough control. In addition, proteinuria may be the common end pathway in which different pathogenetic mechanisms may converge. This explains why immunosuppressive and nonimmunosuppressive approaches are partly not sufficient to halt disease progression. One of the commonest causes of primary glomerulonephritis is mesangioproliferative glomerulonephritis. Among the triggered intracellular pathways involved in mesangial cell proliferation, the mammalian target of rapamycin (mTOR) plays a critical role in cell growth, in turn regulated by many cytokines, disbalanced by the altered glomerulopathy itself. However, when inhibition of mTOR was studied in rodents and in humans with primary glomerulonephritis the results were contradictory. In light of these controversial data, we propose an explanation for these results, to dilucidate under which circumstances mTOR inhibition should be considered to treat glomerular proteinuria and finally to propose mTOR inhibitors to be prospectively assessed in clinical trials in patients with primary mesangioproliferative glomerulonephritis, for which a satisfactory standard immunosuppressive regimen is still pending. 1. Introduction The universal and growing impact of chronic diseases is undoubtedly high. While there has been little attention paid to kidney disease on a public health level, the reality is that many countries hardly bear the costs of providing end-stage renal disease care through renal replacement therapy. According to the latest USRDS report, while the prevalence of diabetes has clearly increased and the prevalence of congestive heart failure has remained stable, the prevalence of chronic kidney disease appears to have declined slightly in 2009, from 15.8 percent to 15.1 percent when calculated with the MDRD-4 formula and from 14.7 percent to 14.5 percent when calculated with the CKD-EPI formula; prevalence estimates of chronic kidney disease in USA in 1988–1994 had been 12.8 and 12 percent, respectively [1]. Obviously, differences in the prevalence estimates may in part differ depending on the criteria and equations employed. Among the most frequent causes of end-stage renal disease, glomerulonephritis ranks third worldwide. Mesangioproliferative glomerulonephritis, mostly IgA nephropathy, is
Injuria renal aguda en la sepsis grave
Trimarchi,Hernán; Nozieres,Christian; Cámpolo Girard,Vicente; Lombi,Fernando; Smith,Cristian; Young,Pablo; Pomeranz,Vanesa; Forrester,Mariano;
Medicina (Buenos Aires) , 2009,
Abstract: sepsis affects 40% of critically ill patients, with a reported mortality of approximately 30% in severe sepsis, raising to 75% when acute kidney injury ensues, which occurs in about 20-51% of cases. the present study consists on a one-year prospective, observational, longitudinal trial undergone in 80 severe septic patients to determine the risk of development of acute kidney injury and its relationship with mortality; the association of the clinical course and blood parameter variations with mortality; the severe sepsis mortality rate; an eventual correlation between death and septic focus, and to assess mortality predictibility based on initial creatinine levels and final variations. two groups were defined: dead (n=25) and not-dead (n=55). according to creatinine on admission, 39 subjects presented with normal creatinine levels (10 deaths) and 41 presented elevated creatinine measurements (15 deaths); regarding final creatinine levels, 48 presented normal levels and 7 patients died, while 32 developed acute kidney injury, with 18 deaths. of the total of 25 deaths, 72% presented renal injury. seven alive patients and 2 deceased patients required hemodialysis. the most frequent primary septic focus was the airway (26.4%). the development of kidney injury is a high predictor of mortality in sepsis, independent of initial serum creatinine levels. older patients, hypertension, a higher apache score, a more severe degree of anemia, hypoalbuminemia, hyperphosphatemia and hyperkalemia were associated with a higher mortality rate. the global mortality was: 31.3%. the failure to identify the primary septic focus was associated with higher mortality. the respiratory focus was related with a higher risk to require hemodialysis.
Dual renin-angiotensin system blockade plus oral methylprednisone for the treatment of proteinuria in IgA nephropathy
Trimarchi,Hernán; Muryan,Alexis; Young,Pablo; Forrester,Mariano; Iotti,Alejandro; Pereyra,Horacio; Lombi,Fernando; Seminario,Omar; Alonso,Mirta; Iotti,Roberto;
Medicina (Buenos Aires) , 2007,
Abstract: renin-angiotensin system inhibition is a widely accepted approach to initially deal with proteinuria in iga nephropathy, while the role of immunosuppressants remains controversial in many instances. a prospective, uncontrolled, open-label trial was undertaken in patients with biopsy-proven iga nephropathy with proteinuria > 0.5 g/day and normal renal function to assess the efficacy of a combination treatment of angiotensin converting enzyme inhibitors plus angiotensin receptor blockers enalapril valsartan coupled with methylprednisone to decrease proteinuria to levels below 0.5 g/day. twenty patients were included: age 37.45 ± 13.26 years (50% male); 7 patients (35%) were hypertensive; proteinuria 2.2 ± 1.86 g/day; serum creatinine 1.07 ± 0.29 mg/dl; mean follow-up 60.10 ± 31.47 months. iga nephropathy was subclassified according to haas criteria. twelve patients (60%) were class ii; seven (35%) were class iii and one (5%) class v. all patients received dual reninangiotensin system blockade as tolerated. oral methylprednisone was started at 0.5 mg/kg/day for the initial 8 weeks and subsequently tapered bi-weekly until the maintenance dose of 4 mg was reached. oral steroids were discontinued after 24 weeks (6 months) of therapy but renin-angiotensin inhibition remained unchanged. at 10 weeks of therapy proteinuria decreased to 0.15 ± 0.07 g/day (p < 0.001) while serum creatinine did not vary: 1.07 ± 0.28 mg/dl (p=ns). after a mean follow-up of 42.36 ± 21.56 months urinary protein excretion (0.12 ± 0.06 g/day) and renal function (serum creatinine 1.06 ± 0.27 mg/dl) remained stable. no major side effects were reported during the study. renin-angiotensin blockade plus oral steroids proved useful to significantly decrease proteinuria to < 0.5 g/day in patients with iga nephropathy without changes in renal function.
"Síndrome complejo de malnutrición e inflamación" en la hemodiálisis crónica
Young,Pablo; Lombi,Fernando; Finn,Bárbara C.; Forrester,Mariano; Campolo-Girard,Vicente; Pomeranz,Vanesa; Iriarte,Romina; Bruetman,Julio E.; Trimarchi,Hernán;
Medicina (Buenos Aires) , 2011,
Abstract: protein-energy wasting (pew) and inflammation are usually common and concurrent conditions in maintenance dialysis patients and associated with poor prognosis. low appetite and hypercatabolic states are common features. in dialysis patients, the former has been suggested to be secondary to inflammation; however, the evidence is not conclusive. hence, the term malnutrition-inflammation complex syndrome (mics) was coined to include this clinical entity, regardless the original causes. possible causes of mics include comorbid illnesses, oxidative stress, nutrient loss through dialysis, hyporexia, uremic toxins, decreased clearance of inflammatory cytokines, volume overload, increased blood phosphate and dialysis-related factors. mics is believed to be the main cause of erythropoietin hypo-responsiveness, cardiovascular atherosclerotic disease, decreased quality of life, hospitalization and increased mortality in dialysis patients. because mics leads to a low body mass index, hypocholesterolemia, decrease in muscle mass, hypocreatininemia and hypohomocysteinemia, a "reverse epidemiology" phenomenon of cardiovascular risk factors can occur in dialysis patients. therefore, obesity, hypercholesterolemia, and increased blood levels of creatinine and homocysteine, within certain limits, appear to be protective and paradoxically associated with a better outcome. there is no consensus about how to determine the degree of severity of mics or how to manage it. several diagnostic tools and treatment modalities are discussed in this paper. the correct management of mics may diminish the cardiovascular disease, main cause of death in this population.
Proteinuria, 99mTc-DTPA Scintigraphy, Creatinine-, Cystatin- and Combined-Based Equations in the Assessment of Chronic Kidney Disease
Hernán Trimarchi,Alexis Muryan,Agostina Toscano,Diana Martino,Mariano Forrester,Vanesa Pomeranz,Fernando Lombi,Pablo Young,María Soledad Ra?a,Alejandra Karl,M. Alonso,Mariana Dicugno,Clara Fitzsimons
ISRN Nephrology , 2014, DOI: 10.1155/2014/430247
Abstract: Background. Precise estimation of the glomerular filtration rate (GFR) and the identification of markers of progression are important. We compared creatinine, cystatin, and combined CKD-EPI equations with scintigraphy to measure GFR and proteinuria as markers of progression. Methods. Cross-sectional, observational study including 300 subjects. CKD was classified by scintigraphy. Determinations. Creatinine, 24-hour creatinine clearance, cystatin, Hoek formula, and creatinine, cystatin, and combined CKD-EPI equations. Results. In the global assessment, creatinine CKD-EPI and combined CKD-EPI equations yielded the highest correlations with : ρ = 0.839, and ρ = 0.831, . Intergroup analysis versus : control G, creatinine clearance ρ = 0.414, P = 0.013; G3, combined CKD-EPI ρ = 0.5317, ; G4, Hoek ρ = 0.618, , combined CKD-EPI ρ = 0.4638, ; and G5, creatinine clearance ρ = 0.5414, , combined CKD-EPI ρ = 0.5288, . In the global assessment, proteinuria displayed the highest significant correlations with cystatin (ρ = 0.5433, ) and cystatin-based equations (Hoek: , ). When GFR < 60?mL/min: in stage 3, proteinuria-cystatin (ρ = 0.4341, ); proteinuria-Hoek (ρ = ?0.4105, ); in stage 4, proteinuria-cystatin (ρ = 0.4877, ); proteinuria-Hoek (ρ = ?0.4877, P = 0.0026). Conclusions. At every stage of GFR < 60?mL/min, cystatin-based equations displayed better correlations with . Proteinuria and cystatin-based equations showed strong associations and high degrees of correlation. 1. Introduction In clinical practice, it is critical to assess kidney function in a precise and accurate manner. Measurement of the glomerular filtration rate (GFR) is considered the best method that reflects kidney function, both in health and in disease [1]. The Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines, widely employed in clinical practice, stratify CKD into 5 stages according to the GFR estimated through the depuration of creatinine [2]. During the last decades, serum creatinine has been the most frequently employed marker to estimate GFR. The K/DOQI guidelines emphasize the necessity to assess GFR employing equations based on serum creatinine and not to rely on serum creatinine concentration alone [2]. The most commonly used creatinine-based formulae include Crockoft-Gault, adjusted to age, weight, and gender, and the Modification of Diet in Renal Disease (MDRD) and its variants, focused on estimating GFR [3]. Finally, Chronic Kidney Disease Epidemiology (CKD-EPI) equation, published in 2009 appears to be more exact than the previous ones in estimating GFR [1]. All these
Constitutive Overexpression of the OsNAS Gene Family Reveals Single-Gene Strategies for Effective Iron- and Zinc-Biofortification of Rice Endosperm
Alexander A. T. Johnson, Bianca Kyriacou, Damien L. Callahan, Lorraine Carruthers, James Stangoulis, Enzo Lombi, Mark Tester
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0024476
Abstract: Background Rice is the primary source of food for billions of people in developing countries, yet the commonly consumed polished grain contains insufficient levels of the key micronutrients iron (Fe), zinc (Zn) and Vitamin A to meet daily dietary requirements. Experts estimate that a rice-based diet should contain 14.5 μg g?1 Fe in endosperm, the main constituent of polished grain, but breeding programs have failed to achieve even half of that value. Transgenic efforts to increase the Fe concentration of rice endosperm include expression of ferritin genes, nicotianamine synthase genes (NAS) or ferritin in conjunction with NAS genes, with results ranging from two-fold increases via single-gene approaches to six-fold increases via multi-gene approaches, yet no approach has reported 14.5 μg g?1 Fe in endosperm. Methodology/Principal Findings Three populations of rice were generated to constitutively overexpress OsNAS1, OsNAS2 or OsNAS3, respectively. Nicotianamine, Fe and Zn concentrations were significantly increased in unpolished grain of all three of the overexpression populations, relative to controls, with the highest concentrations in the OsNAS2 and OsNAS3 overexpression populations. Selected lines from each population had at least 10 μg g?1 Fe in polished grain and two OsNAS2 overexpression lines had 14 and 19 μg g?1 Fe in polished grain, representing up to four-fold increases in Fe concentration. Two-fold increases of Zn concentration were also observed in the OsNAS2 population. Synchrotron X-ray fluorescence spectroscopy demonstrated that OsNAS2 overexpression leads to significant enrichment of Fe and Zn in phosphorus-free regions of rice endosperm. Conclusions The OsNAS genes, particularly OsNAS2, show enormous potential for Fe and Zn biofortification of rice endosperm. The results demonstrate that rice cultivars overexpressing single rice OsNAS genes could provide a sustainable and genetically simple solution to Fe and Zn deficiency disorders affecting billions of people throughout the world.
International Trade and Unemployment in Less Developed Countries  [PDF]
Fernando Mesa
Theoretical Economics Letters (TEL) , 2012, DOI: 10.4236/tel.2012.25101
Abstract:

The main interest focus of this paper is the relation between international trade and the labour market, with an emphasis on the unemployment rate, and the allocation of workers among sectors. A general trade equilibrium model with three sectors is constructed for a less developed country. An informal and un-tradable sector is characterised by flexible wages, while the other two sectors are tradable, export and import sectors. The model imposes a binding minimum wage on unskilled labour and wage distortions on skilled labour. Comparative statics are used to analyse the effects on the labour market of an open economy, a rise in the minimum wage and a positive productivity shock in the export sector.

Intergenerational Real Wages, Technological Change, and Economic Growth in Colombia  [PDF]
Fernando Mesa
Modern Economy (ME) , 2016, DOI: 10.4236/me.2016.72015
Abstract: This paper focuses on the decomposition of real wages in Colombia both by workers’ ages and by cohorts, which overlap over time. The paper analyses how the Colombia’s labour structure has undergone important changes in the period 1982-2007. This period has been characterized by a demographic transition that has tilted the balance from a relatively young population to an older one. The effects of capital accumulation have been estimated and modelled considering the presence of ever more sophisticated machinery, usually replacing less-skilled, younger workers, in relation to older and more qualified ones. In general real wages present a curved shape for each generation, as is acknowledged in the life-cycle hypothesis, according to which people generally start their working life with low incomes and rising debts and then obtain higher income and accumulate assets.
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