Hydrochemical characteristics and formation mechanisms of groundwater in west Zoucheng City, Shandong Province, China.

Groundwater is an important water source for domestic, industrial, and agricultural use in the western part of Zoucheng, China. Understanding its hydrochemical characteristics and formation mechanisms is important for the sustainable development and utilization of groundwater. In this study, 36 water samples were collected during the wet and dry seasons, respectively, and the hydrochemical components such as K+, Na+, Ca2+, Mg2+, Cl-, SO42-, HCO3-, NO3-, F-, TH, and TDS were analyzed. A graphical method, correlation analysis, and principal component analysis were applied to explore the hydrochemical characteristics and evolution mechanisms of groundwater in the study area. The results show that the orders of the anion and cation concentrations of karst groundwater and pore groundwater are Ca2+ > Na+ > Mg2+ > K+ and HCO3- > SO42- > Cl- > NO3- > F-, respectively. On the whole, the karst groundwater quality is better than the pore groundwater quality, which in turn is better than the surface water quality. In addition, water quality in the dry season is better than water quality in the wet season for all the three water sources. The hydrochemical types of groundwater are complex and changeable. Compared with dry seasons, HCO3 and SO4 type water increase during the wet seasons, while the Cl type and Mg type water decrease. Na type is significantly more prevalent in pore groundwater than in karst groundwater. The chemical formations of karst groundwater and pore groundwater in the dry and wet seasons are mainly affected by water-rock interactions and human activities.

[Effect of continuous renal replacement therapy started at different time on patients with multiple organ dysfunction syndrome].

OBJECTIVE: To explore the effects of continuous renal replacement therapy (CRRT) on serum cytokines and prognosis in multiple organ dysfunction syndrome (MODS) patients based on different therapeutic opportunities. METHODS: A total of 34 MODS patients in the treatment of CRRT after admission to ICU of our hospital between July 2008 and October 2010 were recruited. Based on the time interval from the onset of MODS to the initiation of CRRT, the patients were stratified into early group (0 - 3 days, n = 16) and late group (4 - 10 days, n = 18). Both groups of MODS patients received conventional treatment in addition to 72 hours of high-volume hemofiltration (HVHF). The serum levels of such inflammatory mediators as interleukin (IL)-1ß, interleukin-1 receptor antagonist (IL-1Ra), IL-6, tumor necrosis factor (TNF)-α, soluble tumor necrosis factor receptor1 (sTNFR1) and IL-10 were detected by enzyme linked immunosorbent assay (ELISA) before CRRT (0 h) and 6, 12, 18, 24, 48 and 72 h during the treatment of CRRT. Dynamic APACHEII scores were also evaluated. RESULTS: (1) The early group had lower serum levels of IL-1ß, IL-6, IL-10 and higher IL-1Ra, L-1Ra/IL-1ß ratio at 72 h than those of 0 h (P < 0.05). And the late group had a declining serum level of IL-1ß, IL-6, TNF-α and IL-10 and a rising ratio of IL-1Ra and IL-1Ra/IL-1ß during the first 24 h (P < 0.05). As compared with the late group, the early group had a lower level of IL-10 [(25 ± 12) vs (51 ± 33) ng/L] and higher ratios of IL-1Ra and IL-1Ra/IL-1ß at 72 h [(1382 ± 899 vs (683 ± 188) ng/L, (54 ± 10) vs (23 ± 6)] (both P < 0.05). (2) The early group had a lower APACHEIIscore than the late group at 0 h (P < 0.05). APACHEII score at 72 h was significantly lower than 0 h in the early group. And there was no obvious change in the late group. There was no statistical difference in the numbers of MODS patients with dysfunctional organs number ≥ 4 at 0 h in both groups. The number of MODS patients with dysfunctional organs number ≥ 4 at 72 h was lower than 0 h in the early group (P < 0.05). And there was no statistical difference in the late group. CONCLUSION: Regulating the ratio of anti-inflammatory/pro-inflammatory mediators is critical in the immunomodulation of CRRT. And CRRT may provide more clinical benefits in the early phase (0 - 3 days) of MODS.