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Y Xiong

Publications and source records attributed to Y Xiong.

202 records · Page 12Linked to original sources

Characterization of structure and diffusion behaviour of Ca-alginate beads prepared with external or internal calcium sources.

Ca-alginate beads were prepared with either external or internal calcium sources. The structures of both beads were investigated with the aid of scanning electron microscopy (SEM) and confocal microscopy. It was shown that the beads with internal calcium source had a looser structure and bigger pore size than those with external calcium source. The attempts to interpret the difference were carried out by determining the Ca content within the beads at various times, which indicated that it was the different gelation mechanisms that caused the difference of structures of both beads. Furthermore, it was also found that the diffusion rate of haemoglobin (Hb) within the beads with an internal calcium source was faster than that of the beads with an external one, which was consistent with the observation of their structures.

Alginates↗

Alterations in cerebral energy metabolism induced by traumatic brain injury.

Energy metabolism of the brain is unique, possessing high aerobic metabolism with no significant capacity for anaerobic glycolysis and limited tissue stores of glucose. A steady supply of oxygen and glucose is essential in order to maintain cerebral function and integrity. Extensive research in experimental and human head injury has been conducted regarding the delivery of oxygen and outcome. This research has provided evidence which indicates that in addition to the availability of oxygen and glucose, other factors, such as perturbation of mitochondrial energy transducing processes which also follow head trauma, play significant roles. In this paper, the salient findings from biochemical studies of experimental and clinical brain injury are summarized and indicate that the mitochondrial respiratory chain-linked oxidative phosphorylation and calcium transport are compromised by trauma-induced brain injury and support the idea that oxidative stress and perturbation of cellular calcium homeostasis play significant roles in traumatic brain injury.

Brain↗

Coagulation and cytokine profile after major hepatobiliary surgery in Chinese patients.

BACKGROUND/AIMS: Hypercoagulability and increased circulating cytokine levels have been separately reported after surgical operations. We investigated whether the cytokine level and postoperative coagulation profile would change similarly in Chinese patients undergoing major hepatobiliary surgery. METHODOLOGY: Serial serum levels of IL-6, IL-1 beta and TNF-alpha were measured by colorimetric ELISA. Serial coagulation profile was measured by thrombelastography. Hemoglobin and white cell counts were also measured serially. RESULTS: Only mild hypercoagulability was found at the 12th and 144th hours, evidenced by shortening of r-time and k-time on thrombelastography (P < 0.05). IL-6 and IL-1 beta levels were significantly raised from the 12th hour (P < 0.01) while TNF-alpha level was unchanged. From the 3rd hour to the 48th hour, there was negative correlation between IL-6 levels and various thrombelastographic parameters such as coagulation index (r = -0.777, P < 0.001); k-time (r = 0.478, P < 0.05); maximum amplitude (r = -0.688, P < 0.01) and angle (r = -0.665, P < 0.01). CONCLUSIONS: We observed a much milder degree of hypercoagulability in Chinese patients after major hepatobiliary surgery as compared to those reported in other operations in non-Chinese patients. Unlike in sepsis where a close link between increased cytokine levels and hypercoagulability has been reported, increase in IL-6 was associated with less hypercoagulability in Chinese patients after major hepatobiliary surgery.

Adult↗