Characteristics and seasonal variations of pH in the southern shelf of the Caspian sea

This paper presents distribution and seasonal variations of pH over the southern Caspian Shelf adjacent to Iran. The pH data were collected down to 200m depth in two areas in east [off Babolsar in Mazandaran] and west [off Kiyashahr in Gilan] of the Caspian Sea southern coast. The data were collected using a pH sensor of a CTD probe in summer 2003 and spring and autumn 2004. In summer, when the surface water temperature was highest and the strongest seasonal thermo cline existed, the maximum value for pH was observed. In this season, pH had a value of 8.35-8.4 at the water surface. This amount reduced to 8.2 at 80-m level and even deeper waters. In autumn, the pH was less than summer and was mainly 8.25 at the water surface outside of the shelf and 8.3-8.35 in the shelf and it gradually reduced by decreasing the depth. In early spring, during the formation process of new seasonal thermo cline, low temperature and maximum local river inflow, pH at the water surface was mainly 8.25 and reduced to 8.2 at 30-m level. The results showed that seasonal variations of pH in the southern Caspian Shelf and the coastal waters adjacent to Iran is a function of seasonal variations in water temperature, characteristics of thermo cline, local rivers chemical characteristics and discharges, and production or degradation processes

Long-term follow-up of children with steroid-responsive Nephritic Syndrome

Nephrotic syndrome is one of the most remarkable diseases in childhood. The majority of patients have prompt response to corticosteroids. Methods: In this study, we retrospectively evaluate the outcome of patients with steroid-responsive nephritic syndrome. Medical records from January 1996 to September 2006 were reviewed to identify all children with steroid sensitive nephrotic syndrome at the Pediatric Medical Center, Tehran, Iran. Initial steroid therapy was 60 mg/m[2] per day for four weeks. Levamisole, a steroid-sparing agent, was prescribed at a dose of 2.5 mg/kg on alternate days in conjunction with alternate-day prednisolone. If no benefit was observed by three months, levamisole was discontinued and immunosuppressive therapy with cyclophosphamide at a dose of 3 mg/kg daily for 8 weeks, or cyclosporin A at a dose of 3-5 mg/kg was prescribed. Of 745 children with steroid sensitive nephrotic syndrome, 63.1% of patients were male. The most common causes were minimal change disease [98/324, 30.2%] and focal segmental glomerulosclerosis [81/324, 25%]. At presentation, microscopic hematuria was found in 22.6% of the patients. During follow-up, 9.2% had no relapse at any time, while 15.8% were frequent relapsers. The remission period ranged from 3.5 to 168 months. At the last follow-up, 57.6% of the patients were in remission, 37.7% relapsed and 29 children developed chronic renal failure. The outcome of nephrotic syndrome was not associated with age or gender. The end clinical status of patients correlated with duration of remission, number of subsequent relapses and response to cytotoxic agents. Conclusion: Steroid-responsive nephrotic syndrome in children should be followed over a long period, especially patients with early relapse. Relapse was seen in more than 90% of patients. Documentation of histopathology by renal biopsy may be helpful to identify those at increased risk for a poor outcome