The role of land use change on the sustainability of groundwater resources in the eastern plains of Kurdistan, Iran.

In this study, land use change and its effects on level and volume of groundwater were investigated. Using satellite images and field measurements, change in land uses was determined from 1998 to 2007. By analyzing the observation wells data and preparing the zoning maps in GIS, groundwater level fluctuations were assessed. Considering the area corresponding to these fluctuations, changes in aquifers volume were calculated. The rain gauge and synoptic stations data were used to calculate meteorological parameters and evapotranspiration. The water requirement of the main crops was determined by CROPWAT software. Results showed an increase in average rainfall and crops water requirement. The classification of satellite images showed that 11,800 ha was increased in lands under irrigated crops cultivation, while 27,655 ha of rangeland was declined in the region. Groundwater levels dropped an average of 7 m, equal to 63.4 MCM reductions in volume of water in the aquifer.

Shigella flexneri: a three-year antimicrobial resistance monitoring of isolates in a Children Hospital, Ahvaz, Iran.

BACKGROUND AND OBJECTIVES: Shigellosis is an acute gastroenteritis that is one of the most common causes of morbidity and mortality in children with diarrhea in developing countries. The purpose of this study was to describe the distribution of Shigella serogroups and serotypes and their antibacterial drug resistance profiles. MATERIALS AND METHODS: Fecal samples of all children suffering from shigellosis who had been admitted to Abuzar Children's Hospital in Ahvaz, southwestern Iran, from September 2008 to August 2010 were examined. Antibiotics susceptibility testing was performed according to the Kirby Bauer disk diffusion method. RESULTS: Shigella flexneri was the predominant serogroup and being identified in 87 isolates (49.8%). The most common S. flexneri serotypes were type 2 (57.5%) and type 1 (21.8%). High rates of resistance were observed to trimethoprime-sulfamethpxazole (85%) and ampicillin (87.5%). CONCLUSION: S. flexneri and its serotypes was the most frequently isolated Shigella species from southwest of Iran, Ahvaz. Identification of predominant S. flexneri serotypes in developing countries can help in prioritizing strategies such as development of effective vaccines.

Nitric oxide and renal protection in morphine-dependent rats.

Morphine treatment for 5 days protects heart against ischemia-reperfusion (IR) injury. This study evaluated the involvement of nitric oxide (NO) in morphine-induced renal protection. Three weeks after right nephrectomy, increasing doses of morphine were administered (20-30 mg kg(-1)day(-1), 5 days) to develop dependence in rats. The left kidney underwent 45-min ischemia and 24-h reperfusion. Some rats were pretreated with naloxone (5 mg kg(-1)) or L-NAME (20 mg kg(-1)). In one group, IR was induced 24h after the last dose of morphine during the withdrawal period. Plasma nitrite/nitrate levels and serum creatinine and BUN were measured. Creatinine clearance and fractional excretion of sodium (FE(Na)) were calculated. Myeloperoxidase (MPO) activity, malondialdehyde (MDA) level, and inducible NO synthase (iNOS) expression were determined and histopathology was studied in the left kidney. IR increased serum creatinine and BUN, plasma NO (p<0.01), FE(Na), iNOS expression (p<0.001), MPO activity, MDA level, and tissue damage and decreased creatinine clearance. Morphine decreased plasma NO (p<0.05 vs IR), serum creatinine and BUN (p<0.01), FE(Na), MPO activity, MDA level, iNOS expression, and tissue damage (p<0.05), but increased creatinine clearance (p<0.05). Pretreatment with naloxone significantly increased NO production and iNOS expression in morphine-treated rats after IR (p<0.01 vs morphine dependence+IR). Pretreatment with L-NAME in morphine-treated rats decreased NO production (10.7+/-1.9, p<0.01 vs morphine dependence+IR) but could not change iNOS expression after IR. Both naloxone and L-NAME significantly abolished the protective effects of morphine dependence on functional and histological factors. The protective effect of morphine dependence on serum creatinine, BUN, FE(Na), and creatinine clearance persisted during the withdrawal period, whereas iNOS expression decreased. NO production was not decreased during the withdrawal period (p>0.1 vs morphine dependence+IR group). Morphine dependence provided renal protection in the acute phase and during withdrawal. Excessive increase or decrease in NO production abolished the effects of morphine, which suggested a role for balanced NO production and iNOS expression.

The mechanism of preventive effect of captopril on renal ischemia reperfusion injury is independent of ATP dependent potassium channels.

BACKGROUND: Renal ischemia reperfusion (IR) injury has been a major source of concern during the past decades and angiotensin converting enzyme (ACE) inhibitors have been successfully used to prevent this injury. There have been some controversial reports about the involvement of K(ATP) channels in the mechanism of action of ACE inhibitors. In this study, we examined the effect of K(ATP) channel blocker (Glibenclamide) on preventive effect of captopril on renal IR injury. METHODS: Male sprauge-dawley rats were pretreated with glibenclamide (1, 5 and 25 mg/kg) and/or captopril (5 mg/kg). They were anesthetized using ketamine (50 mg/kg) and xylazine (10 mg/kg). The left flank was incised and the left renal artery was clamped for 30 minutes. After that, the kidney was reperfused for 2 hours and then the animal was killed. The Right and left kidneys were removed and evaluated for microscopic damage. RESULTS: Captopril reduced renal IR injury while glibenclamide by itself caused no change. Glibenclamide did not change the preventive effect of captopril. CONCLUSION: It seems that the preventive effect of captopril is not directly mediated by K(ATP) channels and further attention should be paid to other receptor-mediated angiotensin II effects.

The preventive effect of captopril or enalapril on reperfusion injury of the kidney of rats is independent of angiotensin II AT1 receptors.

Occlusion of the artery of organs results in ischaemia. The opening of occluded artery results in tissue lesion identified as reperfusion injury (RI). Renin-angiotensin system seems to be involved in the RI. In this study we assessed the effects of different doses of two inhibitors of angiotensin converting enzyme (captopril or enalapril) and an angiotensin receptor type 1 (AT1) receptor blocker (losartan) in the RI of the kidney of rats. Female rats of 200-250 g were anaesthetized and used for RI studies. Different doses of captopril (5, 20 and 80 mg/kg), enalapril (1, 4 and 16 mg/kg) and/or losartan (5, 10 and 20 mg/kg) were used (s.c.) 120 min prior to the initiation of RI. Kidneys were removed and checked histologically for the presence and the grading of ischaemic injury. Appropriate controls were used as well, RI produced lesions comparable with that of ischaemia. Different doses of captopril or enalapril prevented these lesions. This is suggestive of the involvement of renin-angiotensin system in the RI. Different doses of losartan failed to prevent RI lesions which suggest that the effect of captopril or enalapril are not mediated through the AT1 receptors. Further studies on the involvement of AT2 receptor or other independent mechanisms are suggested.