Microbial biogeography of six salt lakes in Inner Mongolia, China, and a salt lake in Argentina.

We used cultivation-independent methods to investigate the prokaryotic biogeography of the water column in six salt lakes in Inner Mongolia, China, and a salt lake in Argentina. These lakes had different salt compositions and pH values and were at variable geographic distances, on both local and intercontinental scales, which allowed us to explore the microbial community composition within the context of both contemporary environmental conditions and geographic distance. Fourteen 16S rRNA gene clone libraries were constructed, and over 200 16S rRNA gene sequences were obtained. These sequences were used to construct biotic similarity matrices, which were used in combination with environmental similarity matrices and a distance matrix in the Mantel test to discover which factors significantly influenced biotic similarity. We showed that archaeal biogeography was influenced by contemporary environmental factors alone (Na+, CO3(2-), and HCO3(-) ion concentrations; pH; and temperature). Bacterial biogeography was influenced both by contemporary environmental factors (Na+, Mg2+, and HCO3(-) ion concentrations and pH) and by geographic distance.

Stent-assisted coiling and balloon-assisted coiling in the management of intracranial aneurysms: A systematic review & meta-analysis.

BACKGROUND: Stent-assisted coiling and balloon-assisted coiling are well-established minimally invasive techniques for treatment of intracranial aneurysms. The aim of this study was to use meta-analysis methods to compare clinical outcomes of aneurysms treated with stent-assisted coiling versus balloon-assisted coiling. METHODS: We searched for two-arm prospective studies and retrospective studies that compared the clinical outcomes in patients that received stent-assisted or balloon-assisted aneurysm treatment. Database search was performed through May 2015. Odds ratios (OR) with 95% confidence intervals (CI) were used to compare the clinical outcomes in patients that underwent either stent-assisted or balloon-assisted coiling for intracranial aneurysms management. RESULTS: Complete occlusion rates at the end of the coiling procedure were similar between patients that received stent-assisted and balloon-assisted aneurysm treatment (OR=0.763, 95% CI=0.47 to 1.23, P=0.270). However, complete occlusion rates were higher with stent-assisted coiling at 6months or later after the procedure (OR=1.82, 95% CI=1.21 to 2.74). The overall complication rates and retreatment rates in patients with recurrence were similar between stent-assisted and balloon-assisted aneurysm treatments. CONCLUSION: Stent-assisted coiling achieved better complete occlusion rates of aneurysms at 6months or later after the procedure compared to balloon-assisted coiling, without being associated with a higher risk of intraprocedural complications and retreatment.

Effect of subarachnoid hemorrhage on voltage-dependence calcium channel current in cerebral artery smooth muscle cells.

OBJECTIVE: To investigate the effect of subarachnoid hemorrhage (SAH) on voltage-dependent calcium channel (VDCC) current in cerebral artery smooth muscle cells (SMCs), oxyhemoglobins (OxyHb) concentration and vasospasm. METHOD: Thirty-six clean SD rats were used to establish SAH model by injecting autologous arterial blood into suprasellar cistern with the aid of stereotaxic instrument. They were divided into arterial SAH group (14 rats), venous SAH group (13 rats) and sham operation group (9 rats), and OxyHb concentrations were measured in the first two groups. Relative membrane surface area of cerebral artery SMCs, resting potential and VDCC current were measured using a patch clamp at day 3 after modeling; cerebral blood flow (CBF) was measured by using fluorescent microsphere-based lateral flow assay. RESULTS: OxyHb concentration of arterial SAH group (127±4 g/L) was higher than that of venous SAH group (54±6 g/L) and sham operation group (50±5 g/L), with significant difference (P<0.05); The maximum VDCC current (3.22±0.31 pA/pF) of the arterial SAH group was obviously higher than that of venous SAH group (2.19±0.27 pA/pF) and sham operation group (2.18±0.29 pA/pF), also showing a significant difference (P<0.05). For arterial SAH group, VDCC current consisted of L- and R-type calcium current, and for venous SAH group the VDCC current consisted of L-type calcium current; CBF of arterial SAH group (0.83±0.14 ml/g/min) was significantly higher than that of venous SAH group (1.28±0.28 ml/g/min) and sham operation group (1.35±0.19 ml/g/min) (P<0.05). CONCLUSION: The effect of arterial SAH was greater on the expression and function of VDCCs in cerebral artery SMCs than venous SAH. This may be explained by the differences in the concentration and composition of pathogenic agents for vasospasm in the arterial and venous blood, such as OxyHb.

Increasing eutrophication in the coastal seas of China from 1970 to 2050.

We analyzed the potential for eutrophication in major seas around China: the Bohai Gulf, Yellow Sea and South China Sea. We model the riverine inputs of nitrogen (N), phosphorus (P) and silica (Si) to coastal seas from 1970 to 2050. Between 1970 and 2000 dissolved N and P inputs to the three seas increased by a factor of 2-5. In contrast, inputs of particulate N and P and dissolved Si, decreased due to damming of rivers. Between 2000 and 2050, the total N and P inputs increase further by 30-200%. Sewage is the dominant source of dissolved N and P in the Bohai Gulf, while agriculture is the primary source in the other seas. In the future, the ratios of Si to N and P decrease, which increases the risk of harmful algal blooms. Sewage treatment may reduce this risk in the Bohai Gulf, and agricultural management in the other seas.