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Ex vivo hypothermic machine perfusion (HMP) is a strategy for controlling ischemia-reperfusion injury in donation after circulatory death (DCD) liver transplantation. The pH of blood increases with a decrease in temperature and water dissociation, leading to a decrease in [H+]. This study aimed to verify the optimal pH of HMP for DCD livers. Rat livers were retrieved 30 min post-cardiac arrest and subjected to 3-h cold storage (CS) in UW solution (CS group) or HMP with UW-gluconate solution (machine perfusion [MP] group) of pH 7.4 (original), 7.6, 7.8, and 8.0 (MP-pH 7.6, 7.8, 8.0 groups, respectively) at 7–10 °C. The livers were subjected to normothermic perfusion to simulate reperfusion after HMP. All HMP groups showed greater graft protection compared to the CS group due to the lower levels of liver enzymes in the former. The MP-pH 7.8 group showed significant protection, evidenced by bile production, diminished tissue injury, and reduced flavin mononucleotide leakage, and further analysis by scanning electron microscopy revealed a well-preserved structure of the mitochondrial cristae. Therefore, the optimum pH of 7.8 enhanced the protective effect of HMP by preserving the structure and function of the mitochondria, leading to reduced reperfusion injury in the DCD liver.

The machine perfusion (MP) preservation including hypothermic MP (HMP) and midthermic MP (MMP) has been considered as a promising strategy to preserve the functions of liver donated after cardiac death. The importance of understanding liver sinusoidal endothelial cells (LSEC) damage in regulating liver injury during MP has been emphasized. However, the ultrastructural changes in the LSEC and sinusoids around them after MP are unclear.To investigate the ultrastructural changes in the LSEC and sinusoids around them after MP.Porcine liver grafts undergo a warm ischemia time of 60 minutes perfused for 4 h with modified University of Wisconsin gluconate solution. Group A grafts were preserved with HMP at 8 °C constantly for 4 h. Group B grafts were preserved with a rewarming solution at 22 °C by MMP for 4 h. Then the ultrastructural changes in the LSEC and sinusoids in Group A and B were comparatively analyzed by using osmium-maceration scanning electron microscopy with complementary transmission electron microscopy methods.An analysis of the LSEC after warm ischemia revealed that mitochondria with condensed-shaped cristae, abnormal vesicles, reduction of ribosomes and the endoplasmic reticulum (ER) surround the mitochondria appeared. The MP subsequent after warm ischemia alleviate the abnormal vesicles and reduction of ribosomes in LSEC, which indicated the reduction of the ER damage. However, MMP could restore the tubular mitochondrial cristae, while after HMP the condensed and narrow mitochondrial cristae remained. In addition, the volume of the sinusoidal space in the liver grafts after MMP were restored, which indicated a lower risk of pressure injury than HMP.MMP alleviates the ER damage of LSEC by warm ischemia, additionally restore the metabolism of LSEC

Locally known as ‘Njangsa’, Ricinodendron heudelotii refers to groundnut trees with an oily seed that grows widely in Central and West Africa in countries such as Ivory Coast, Ghana, and Nigeria. R. heudellotii or Njangsa serves as one of the significant sources of non-timber forest products of Tropical Africa as it serves a wide range of commodities to the local population. Usage ranges from traditional medicine to home consumption and even local crafts. The seeds, for instance, are marketed locally and exported to Europe. This chapter discusses the phytochemical composition, nutritional values and products of R. heudelotii that have been studied as well as used for traditional practices. R. heudelotii is widely used as traditional medicine for treating cough, yellow fever, anemia, malaria, stomach pain, and intestinal diseases and neutralizing poisons. Throughout this chapter, the discussed scientific findings could further support the application of R. heudelotii in traditional medicine.

The suspension culture system is an increasingly popular method of culturing cells not only because of its up scaling ability, but also the non-enzymatic procurement of cells that is crucial for biomedical research, especially in the fields of pharmacology and regenerative medicine. Hypothetically, by controlling and reducing the shear stress applied to cells in a culture system, the higher viability and proliferation rates. In this study, we analyzed HEK 293 cells cultured with a commercially available spinner flask and our newly developed spinner flask which utilizes the theory of Couette flow for controlling shear stress. Fluid analysis and metabolic analysis of the cultured cells were measured at three different rotational speeds, 40, 50 and 60 rpm. It was apparent that 50 rpm was by far the best speed to proliferate the cells. A further viability test was also done in order to validate our hypothesis. Furthermore, by using the metabolic analysis results, it was observed that in the controlled stress system, the consumption of glucose doubled and lactate production was significantly higher compared to cells that were maintained in the conventional suspension method. Thus, Couette flow based suspension culture system will be a major contributor to the future biomedical and pharmacological field.

[Background] Vascular elasticity is vital for the functions of arterial vessels. The lack of vascular elasticity in arterial walls induces fatal cardiovascular diseases including aortic aneurysms.It has already been known that elasticity is determined by the components such as elastin and collagen, and that blood pulsatile flow affects their expressions. However, this mechanism has not clarified well.Iwasaki et al successfully fabricated three layered bioengineered vessels that had similar elasticity to native arteries with fetal bovine aortic cells using a pulsatile bioreactor regulated flow rate and pressure, and suggested the mechanical stress promoted vascular elastogenesis. In order to clarify the mechanism of arterial elastic fiber formation , we developed rat tissue engineered vessel with physical stimulation by using an orbital shaker.[Method] At first, we isolated rat aortic smooth muscle cells (ASMC) from rat fetuses at embryonic 21 day and harvested them on a polyglycolic acid (PGA) sheet of 2cm×2cm×1mm. After incubation of one week in a CO2 incubator, this sheet was wrapped around a silicone tube. After one week incubation, the cell /PGA construction was placed in a flask. This flask was placed in a CO2 incubator on an orbital shaker, which provided gentle agitation at 50rpm and incubated for two weeks. We histologically and genetically analyzed the cell /PGA construction.[Results] Under orbital shaking condition, cells seemed to localize and maintain their phenotypes. Moreover, elastin deposit was formed in the cell-localized area. Total RNA successfully extracted from the cell/PGA construction. The expression levels of elastin mRNA seemed to be higher under orbital shaking condition than non-shaking condition. [Conclusion] Our results suggested that orbital shaking promoted vascular elastogenesis of the cell /PGA construction and also physical stress by shaking incubation tended to stimulate vascular elastic fiber formation.