Objective Toinvestigatethemolecularmechanismsofmitochondrialpathway-mediated apoptosisinintracranialaneurysminitiationinrabbits.Methods FifteenNewZealandwhiterabbitswere divided into 3 groups using the computer random method. After using bilateral carotid artery ligation for modeling basilar artery aneurysm,they were divided into a 2-day group (n=3),a 7-day group (n=6)(3 of them were used for real-time quantitative polymerase chain reaction [PCR]analysis),and a sham operation group (n=6)(3 of them were used for real-time quantitative PCR analysis). The tissue of apex of basilar artery was harvested and the histopathological changes in the vascular wall were observed. TUNEL staining was used to detect apoptotic cells and immunohistochemical staining,and quantitative analysis was used to analyze inflammatory cell distribution. Real-time quantitative PCR was used to detect the expression of apoptosis-related protein mRNA. Results (1 )After modeling,the apoptotic cells were found at the apex of basilar artery in rabbits (the site of internal elastic layer lesion )of the 2-day group and 7-day group. In the 2-day group after operation,the numbers of apoptotic cells (4. 02 ± 0. 21)were significantly higher than those of the basilar artery trunk (0. 40 ± 0. 13),the left posterior cerebral artery (0. 41 ± 0.22),and the right posterior cerebral artery (0. 29 ± 0. 11). The differences were statistically significant (P<0. 05). After modeling,the numbers of apoptotic cells (5. 01 ± 0. 29)of the 7-day group were significantly higher than those of the basilar artery trunk (0. 49 ± 0. 21),the left posterior cerebral artery (0. 31 ± 0. 12),and the right posterior cerebral artery (0. 41 ± 0. 19)(P<0. 05). The internal elastic layer lesions and apoptotic cells were not observed in the rabbits of the sham operation group. (2)After modeling, the expression levels of caspase 9 (1. 97 ± 0. 23)and caspase-3 mRNA (2. 31 ± 0. 40)at the apex of basilar artery in rabbits of the 7-day group were increased significantly compared with that of the sham group (P<0.01).Conclusion Apoptosisisinvolvedintheearlyprocessofaneurysmsinsimple hemodynamics-induced basilar terminus aneurysm formation. Its molecular mechanisms are activated by Bcl-2-mediated mitochondrial pathway through caspase-9.

Anaerobic ammonium oxidation (ANAMMOX), as its essential advantages of high efficiency and low cost, is a promising novel biological nitrogen elimination process with attractive application prospects. Over the past two decades, many processes based on the ANAMMOX reaction have been continuously studied and applied to practical engineering, with the perspective of reaching 100 full-scale installations in operation worldwide by 2014. Our review summarizes various forms of ANAMMOX processes, including partial nitritation-ANAMMOX, completely autotrophic nitrogen removal over nitrite, oxygen limited autotrophic nitrification and denitrification, denitrifying ammonium oxidation, aerobic deammonification, simultaneous partial nitrification, ANAMMOX and denitrification, single-stage nitrogen removal using ANAMMOX and partial nitritation. We also compare the operating conditions for one-stage and two-stage processes and summarize the obstacles and countermeasures in engineering application of ANAMMOX systems, such as moving bed biofilm reactor, sequencing batch reactor and granular sludge reactor. Finally, we discuss the future research and application direction, which should focus on the optimization of operating conditions and applicability of the process to the actual wastewater, especially on automated control and the impact of special wastewater composition on process performance.
Ammonia ; chemistry ; Bioreactors ; Denitrification ; Nitrification ; Nitrites ; chemistry ; Nitrogen ; chemistry ; Oxygen ; chemistry ; Sewage ; chemistry ; Waste Disposal, Fluid ; methods ; Waste Water ; chemistry