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Although blockade of renin-angiotensin system have been cited as the first line of therapy for the management of diabetic nephropathy (DN), however in a substantial number of patients, progression of renal disease are not completely halted by these agents. We have conducted a double blinded clinical trial to assess the additive effect of pentoxifylline on reduction of proteinuria among patients with type 2 DM under blockade of angiotensin system. The dosage of PTX used in our trial was at a low dosage of 400mg daily and to our knowledge, we did not found article which evaluated the antiproteinuric effect of pentoxifylline in this dosage. One hundred patients with DN and persistent proteinuria despite treatment with losartan and enalapril in at least 3 months before inclusion in the study were randomly assigned to two groups. Control group (n=50, 26 males and 24 females) received losartan and enalapril, while treatment group (PTX Group) (n=50, 28 males and 22 females) was given losartan, enalapril and pentoxifylline 400mg/day for 6 months. At the beginning of the study there were no significant differences in demographic and clinical characteristics of patients including serum creatinine, HbA1c, blood pressure and urinary protein excretion between two groups (P>.05). In the PTX group, the mean rate of urinary protein excretion have significantly decreased from 616.66mg to 378.24 after 3 months (P=.000) and to 192.05mg after 6 months (P=.000) whereas no significant changes were observed in the control group. The beneficial antiproteinuric effect of PTX was not associated to the degree of metabolic control and a reduction of blood pressure. In addition, at the end of study, the mean clearance of creatinine was significantly higher in PTX group (P=.04). In conclusion, PTX can significantly provide additive antiproteinuric effect and slow the decrease in GFR among patients with type 2 DM under blockade of angiotensin system. Aunque el bloqueo del sistema renina-angiotensina ha sido citado como el tratamiento inicial para la nefropatía diabética (ND), en un número significativo de pacientes el avance de la enfermedad renal no se ve frenado en su totalidad por estos agentes. Hemos realizado un ensayo clínico doble ciego para valorar el efecto acumulativo de la pentoxifilina (PTX) en la reducción de la proteinuria en pacientes con diabetes tipo 2 (DM2) con bloqueo del sistema de angiotensina. La dosis de PTX utilizada en nuestro ensayo fue una cantidad baja de 400 mg diarios y, en nuestra experiencia, no logramos encontrar ningún artículo que evaluara el efecto antiproteinúrico de la PTX con esta dosis. De forma aleatoria, se dividieron en dos grupos 100 pacientes con ND y proteinuria persistente a pesar del tratamiento con losartán y enalapril durante al menos tres meses antes de ser incluidos en el estudio. El grupo de control (n = 50, 26 hombres y 24 mujeres) fueron tratados con losartán y enalapril, mientras que el grupo de tratamiento (grupo de PTX: n = 50, 28 hombres y 22 mujeres) recibieron losartán, enalapril y 400 mg/día de pentoxifilina durante 6 meses. Al comienzo del estudio no se encontraron diferencias significativas en las características demográficas y clínicas de los pacientes, incluida la creatinina sérica, HbA1c, presión arterial y excreción urinaria de proteínas entre los dos grupos (p > 0,05). En el grupo de PTX, la tasa media de excreción urinaria de proteína ha disminuido significativamente de 616,66 a 378,24 mg tras 3 meses (p = 0,000) y a 192,05 mg tras 6 meses (p = 0,000), mientras que en el grupo de control no se han observado cambios significativos. El beneficioso efecto antiproteinúrico del PTX no estuvo asociado a la intensidad del cambio metabólico ni a la reducción de la presión arterial. Además, al final del estudio, el aclaramiento medio de creatinina fue significativamente más elevado en el grupo de PTX (p = 0,04). En conclusión, la PTX puede aportar en gran medida un efecto antiproteinúrico acumulativo y ralentizar el grado de filtración glomerular en pacientes con DM2 con bloqueo del sistema de angiotensina.

Introduction: The development of intradialytic hypotension during hemodialysis (HD) in which fluid removal is the primary goal, contributes to the excessive morbidity that is associated with the dialysis procedure. Materials and Methods: In a double blinded clinical trial, we compared the possible effect of intranasal DDAVP with intranasal distilled water as a placebo in prevention of intradialytic hypotension (IDH) in patients with known symptomatic IDH. In the first month of the study, nasal spray of distill water were administrated 30 minutes before all HD session (Placebo Group, Group 1) and then after a 30-day washout period we were used intranasal DDAVP 30 minutes before HD session (Vasopressin Group, Group 2). Blood pressure was measured just before HD, two hours later and after termination of HD. A hypotensive episode was defined as a decline of systolic blood pressure of more than 10mm Hg. Results: In overall Seventeen patients (nine men, eight women; mean age, 47.5 years) with known symptomatic IDH were enrolled in the study. The kind of dialysis membranes, mean of blood flow rate, dialyzate flow rate and ultrafiltration rate were the same in both groups. Each group has 204 HD session (17 * 12). Hypotensive episode occurred 18 times (8.82%) in vasopressin group compared with 125 times (61.27%) in placebo group and there was a significant association between them (p=0.0001). In addition mean arterial blood pressure in vasopressin group was 80.77 and in placebo group was 73.92 and also there was a significant association (p=0.0001). The mean Kt/v in group 1 and 2 were 1.29 and 1.28 without any differences between them (p=0.896). Conclusion: These results indicate that Compared with placebo, Vasopressin is significantly associated with a decreased incidence of intradialytic hypotension episodes during hemodialysis. Introducción: La aparición de hipotensión intradialítica durante la hemodiálisis (HD) en la que el objetivo principal es la eliminación de fluidos, contribuye a una morbilidad excesiva que se asocia con la diálisis. Materiales y métodos: Mediante un ensayo clínico doble ciego, comparamos los posibles efectos de la DDAVP intranasal con los del agua destilada intranasal como placebo en la prevención de la hipotensión intradialítica (HID) en pacientes con HID sintomática diagnosticada. Durante el primer mes del estudio, la pulverización nasal de agua destilada se realizaba 30 minutos antes de todas las sesiones de HD (grupo de placebo, grupo 1) y luego, tras un periodo de reposo de 30 días, utilizamos DDVAP intranasal 30 minutos antes de las sesiones de HD (grupo vasopresina, grupo 2). La presión arterial se medía justo antes de la HD, dos horas después y una vez finalizada la HD. Se definió como episodio de hipotensión la caída de la presión arterial sistólica del más de 10 mmHg. Resultados: Se incluyó en el estudio un total de 17 pacientes (nueve hombres y ocho mujeres de 47,5 años de edad media) con HID sintomática diagnosticada. En ambos grupos, el tipo de membranas de diálisis, la media del flujo sanguíneo, la tasa del flujo dializado y la tasa de ultrafiltración eran los mismos. Ambos grupos se sometieron a 204 sesiones de HD (17 x 12). Los episodios de hipotensión sucedieron en 18 ocasiones (8,82%) en el grupo de vasopresina en comparación con las 125 ocasiones (61,27%) del grupo de placebo y hubo una relación significativa entre ellos (p=0,0001). Además, la presión arterial media en el grupo de vasopresina era de 80.77 y en el grupo de placebo era de 73,92 e igualmente se observó una asociación significativa (p=0,0001). La media Kt/v en el grupo 1 y el 2 fue de 1,29 y 1,28 sin diferencias entre ellos (p=0,896). Conclusión: Estos resultados indican que, en comparación con el placebo, la vasopresina está relacionada de forma significativa con una menor incidencia de los episodios de hipotensión intradialítica durante la hemodiálisis.

The aim of this paper is to present a methodology in three steps to forecast supply chain demand. In first step, various data mining techniques are applied in order to prepare data for entering into forecasting models. In second step, the modeling step, an artificial neural network and support vector machine is presented after defining Mean Absolute Percentage Error index for measuring error. The structure of artificial neural network is selected based on previous researchers' results and in this article the accuracy of network is increased by using sensitivity analysis. The best forecast for classical forecasting methods (Moving Average, Exponential Smoothing, and Exponential Smoothing with Trend) is resulted based on prepared data and this forecast is compared with result of support vector machine and proposed artificial neural network. The results show that artificial neural network can forecast more precisely in comparison with other methods. 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