Search

[Objective] As an important type of coarse-grained sedimentary system and oil and gas reservoir in faulted basins, fan delta and slump fan complex deposition has been the hot topic of research on lacustrine sedimentary and reservoir formation, such as distribution area, evolution period and accumulation model. [Methods] Based on high resolution 3D seismic and drilling and logging data in the A Sag of Melut Basin in central Africa region, the sedimentary characteristics and evolution of fan delta-slump fan complex are studied by using core observation, sequence division, seismic reflection characteristics and seismic attribute analysis. [Results and Conclusions] The results showed that the types of sedimentary facies of fan in the study area included fan delta and slump fan caused by gravity flow, slump fan had two types of morphology characteristic, the first one was line source slump fan controlled by slope break, the second one was multistage slump fan with single point source controlled by steep topographic slope. Combined with seismic profiles and well logging features, five periods of fans were recognized in the Cretaceous study section. The single-stage fan all had the characteristics of retrogradation, the vertical evolution of multiple periods of fans was characterized by "first progradation and later retrogradation" . The fan distribution was the largest at the end of Renk Formation deposition in the Lower Cretaceous, reaching 148 km². However, the fan evolution was mainly influenced by tectonic activity, palaeogeomorphology, provenance supply, and base-level cycle. The fan distribution was larger in the period of strong tectonic activity, abundant provenance supply and large short-axis tectonic uplift, and the slump fan was most developed in the early period of relative base-level rising cycle and decreasing cycle. A new understanding of the sedimentary pattern transformation occurred in the Early Cretaceous and Late Cretaceous in the A Sag was put forward. The exploration potential of the fan delta and slump fan complex deposition in the faulted depression is clarified, which guided the exploration deployment. [ABSTRACT FROM AUTHOR]

Objective: To explore the effects of protoporphyrin IX (PpIX)-mediated photodynamic therapy (PDT) on induction of apoptosis and death in colon cancer cell and the underlying mechanisms.
 Methods: The cell killing effect of PDT on HCT116 cell was determined by cell counting kit (CCK). The cells were divided into a control group, a single light group, a single PpIX group, and a PDT group. Hoechst 33342 and flow cytometry was used to assess the cell apoptosis. Western blot was employed to analyze the expressions of bcl-2, bax, and caspase-3. Reactive oxygen species (ROS) was detected by flow cytometry.
 Results: The viability of HCT116 cell was decreased gradually with the increase of irradiation dose (P<0.05). Compared to the other 3 groups, ROS production, the number of apoptotic cells and the protein expressions of bax and caspase-3 in PDT group increased, while bcl-2 expression was decreased (P<0.05).
 Conclusion: PpIX-mediated PDT can enhance the apoptosis in HCT116 cell, which may be related to mitochondrial apoptosis pathway.