ABSTRACT
Organophosphorus pesticide poisoning causes tens of thousands of deaths each year across the world. Poisoning includes acute cholinergic crisis as a result of AChE inhibition, intermediate syndrome (IMS) due to neuromuscular necrosis and organophosphate-induced delayed neuropathy (OPIDN) due to inhibition of neuropathy target esterase (NTE). Standard treatment for acute poisoning involves administration of intravenous atropine, oxime 2-PAM to counter AChE inhibition and diazepam for CNS protection. However clinical trials showed ineffectiveness of the standard therapy regimen. Although new oximes that can reactivate both peripheral and cerebral AChE and other prophylactic agents such as human serum butyrylcholinesterase (Hu BChE), sodium bicarbonate, huperzine A (a reversible ChE inhibitor) with imidazenil (a GABAA receptor modulator) have been proved effective in animal models, systematic clinical trials in patients are warranted. For IMS which is non-responsive to standard therapy, supportive therapy specifically artificial respiration followed by recovery is indicated. For OPIDN which has a different target (NTE) than AChE, standard therapy is ineffective. However neuroprotective drugs such as corticosteroids proved partially effective. Pretreatment with protease inhibitor PMSF has been shown to protect the aging of NTE and prevent the development of delayed symptoms in hens. Since the biology of NTE is being explored, new pharmacological agents should be developed in future. OP pesticide poisoning is a serious condition that needs rapid diagnosis and treatment. Since respiratory failure is the major reason for mortality, artificial respiration, careful monitoring, appropriate treatment and early recognition of OP pesticide poisoning may decrease the mortality rate among these patients.
ABSTRACT
A number of studies have demonstrated that the urinary ion activity product (IAP) of calcium oxalate (CaOx), as an index of urinary CaOx supersaturation (SS), is higher in renal stone formers than in normal subjects. Besides, the relation between CaOx SS and lithogenesis, crystal CaOx exposition can produce tubular cell as well as renal interstitial lesions. The aim of our study was to evaluate the possible relationship between CaOx SS and tubulointerstitial (TI) damage in an animal model of hyperoxaluria. During four weeks, male Sprague-Dawley rats received: G1 (n = 8) control regular water, and G2 (n = 8) 1% ethylene glycol (ETG) (precursor for oxalates) in drinking water. In order to evaluate urinary CaOx SS, IAP assessed by Tisselius formula was performed. At the end of the study, renal lesions were evaluated by light microscopy and immunohistochemistry. Animals from G2 (ETG) presented higher (p < 0.01) values of: a) urinary oxalate excretion; b) urinary CaOx SS; c) crystalluria score; d) proteinuria; and lower (p < 0.01) creatinine clearance, with respect to the control group (G1). Moreover, pathology studies showed that rats from G2 (ETG), presented significant TI lesions characterized by a higher (p < 0.01) score of: a) tubular atrophy; inflammatory infiltrates (monocyte/macrophage); c) crystal deposits; d) intersticial fibrosis; e) interstitial alpha-smooth muscle actin; f) collagen type III; g) TI TGF beta 1 compared with G1 (control). Rats from G2 (ETG) presented a high correlation between urinary CaOx SS and most of the TI damage parameters evaluated, in especial with interstitial fibrosis. Both, inflammatory infiltrates and urinary CaOx SS were the most significant variables related to interstitial fibrosis. Finally, since hyperoxaluric animals showed higher urinary CaOx SS associated with higher renal TI damage, the results from this study suggest the presence of a tight link between urinary CaOx SS and renal TI damage. Considering these findings we think that urinary CaOx SS control rises in importance beyond nephrolithiasis
Subject(s)
Animals , Male , Rats , Calcium Oxalate , Hyperoxaluria , Kidney Calculi , Kidney Tubules , Ions , Rats, Sprague-Dawley , Regression AnalysisABSTRACT
Con el fin de investigar la relación entre el estado redox y la hemodiálisis (HD), en este estudio decidimos evaluar una serie de parámetros de estrés oxidativo y defensas antioxidantes en un grupo de pacients que recibían tratamiento hemodialítico crónico y un gupo control apareado por edad... Podemos concluir que: 1)en los pacientes en HD crónica existen profundas alteraciones de las defensas antioxidantes circulantes; b)que un estrés oxidativo adicional se produce durante la sesión de HD. Por otra parte, el tratamiento con IECA mejora varios componentes de las defensas entioxidantes en este grupo de pacientes. (AU)(Premio Dr. Víctor R. Miatello de la Sociedad Argentina de Nefrología 1998)
Subject(s)
Humans , Antioxidants , Renal Dialysis , Renal Insufficiency, Chronic/therapy , Enalapril , Erythropoietin , Reactive Oxygen Species , Oxidative StressABSTRACT
El sistema renina-angiotensina (SRA) parece influir en el desarrollo renal fundamentalmente en su vasculogenésis. Recientes trabajos indican que el SRA es estimulado durante la organogenésis renal y el crecimiento renal neonatal, las células del SRA son activadas y/o redistribuidas en muchas situaciones que evidencian crecimiento renal. Con el objeto de evaluar este efecto veinte ejemplares de Rana Catesbeiana en período de prometamofosis, cuyo peso medio fue de 4,8 + - 0,1g fueron criados en bateas plásticas con agua libre de cloro a una temperatura que osciló entre 22 y 25 grados C con un fotoperíodo de 12 horas día 12 horas noches. A diez de estos animales se los mantuvo en condiciones similares pero al agua se le agregó 20 mg/litro de enalapril (ENAL). Dos semanas después del período denominado climax metamórfico los animales se pesaron y se sacrificaron por decapitación. Se realizaron estudios morfométricos e inmunohistoquímicos