Objective To study the relation between changes of the hepatic energy metabolism and allograft viability in early phase after orthotopic liver transplantation, arterial blood ketone body ratio (AKBR) was measured in pre- intra and post-operative phase. Methods The monkeys were divided into two groups in accordance with survived times. A group (＞24h), 5 monkeys survived 29—168 postoperative hours; B group (＜24h), 9 monkeys survived only 5—22 hours. Results AKBR in all models immediately decreased to extraordinarily low state in anhepatic-phase (versus preanhepatic phase, Ｐ＜0.01), and A group recovered rapidly to the normal levels, and maintained continuously for 12 postoperative hours above the level of 0.7. In contrast in B group, AKBR decreased below 0.7 rapidly and failed to restore to the normal level. Within 12 hours postoperatively, in B group, AKBR was lower than 0.4. Conclusion AKBR is a sensitve indicator to the allograft viability in the early phase after hepatic transplantation.
Mental fatigue is a subjective fatigue state caused by long-term brain activity, which is the core of health problems among brainworkers. However, its influence on the process of brain information transmission integration is not clear. In this paper, phase amplitude coupling (PAC) between theta and gamma rhythm was used to study the electroencephalogram (EEG) data recorded before and after mental fatigue, so as to explain the effect of mental fatigue on brain information transmission mechanism. The experiment used a 4-hour professional English reading to induce brain fatigue. EEG signals of 14 male undergraduate volunteers before and after mental fatigue were recorded by Neuroscan EEG system. Phase amplitude coupling value was calculated and analyzed. t test was used to compare the results between two states. The results showed that theta phase of more than 90% of the electrodes in the whole brain area jointly modulated gamma amplitude of the right central area and the right parietal area, and the coupling effect among different brain regions significantly decreased (P < 0.05) when participants had felt mental fatigue. This paper shows that phase amplitude coupling can explain the influence of mental fatigue on information transmission mechanism. It could be an important indicator for mental fatigue detection. On the other hand, the results also provide a new measure to evaluate the effect of neuromodulation in relieving mental fatigue.
Abstract A new type of artificial material could possibly be produced by combination of osteoblast with bioactive material in culture, and thus, make the material "alive" . To study the behavior of osteoblast cultured with bioactive materials, the osteoblasts were isolated from the periosteum of Newzeland Rabbits tibia, and cultured in RPMI1640 medium. After 13 subcultures, the cells were identified as osteoblast in vitro by electron microscope, AKP activity and detection of mineral deposition ability. The osteoblasts were subcultured with three bioactive materials: bioactive glass ceramics (BGC), hydroxyapatite (HA), and double phase hydroxyapatite (HA/TCP). After incubationfor 48 hours, scan electron microscope, 3H-TDR, XRD, RS and EDXAwere performed. The results showed that the osteoblasts grew on the HA/TCR had a higher proliferation rate and better osteoblastoid shape than those grew on BCG and HA. Themechanism of the growth of osteoblasts on bioactive materials was discussed, and the factors influencing the growth of osteoblast were analyzed.
ObjectiveTo investigate the current status of symptom burden and psychological distress among lung cancer patients in the diagnostic phase, and to explore the chain mediating role of social support and resilience between symptom burden and psychological distress. MethodsThe patients with lung cancer in the diagnostic phase who were treated in the Department of Thoracic Surgery of the Second Xiangya Hospital of Central South University from October 2022 to June 2023 were investigated by a general information questionnaire using the MD Anderson Symptom Inventory, the Social Support Rating Scale, the Connor-Davidson Resilience Scale, and the Distress Thermometer. The chain mediating role of social support and resilience between symptom burden and psychological distress was analyzed. ResultsA total of 413 lung cancer patients were enrolled, including 173 males and 240 females, aged (54.69±10.82) years. The detection rate of psychological distress among lung cancer patients in the diagnostic phase was 48.18%, and the average score was (3.84±2.50) points. Psychological distress was positively correlated with symptom burden (P<0.01), and negatively correlated with social support and resilience (P<0.01). The mediating effect of resilience between symptom burden and psychological distress was significant. The chain mediating effect of social support and resilience between symptom burden and psychological distress was also significant. ConclusionLung cancer patients in the diagnostic phase have a high detection rate of psychological distress. Symptom burden can directly impact psychological distress, and can affect psychological distress through the indirect path of resilience as well as the chain mediating path between social support and resilience among lung cancer patients in the diagnostic phase.
Objective To discuss the technical keypoints of the second-phase diaplasis treatment after Hartmann operation. Methods Twenty-one cases of the second-phase diaplasis operation of Hartmann operation in this hospital from January 2003 to December 2007 were analysed retrospectively. Results In this group, stapler technique was used in 15 cases, anastomotic ring was used in 3 cases, and one-layer suture was used in 3 cases. The time of these operations was between 118 min and 240 min (mean 164 min). Neither stomal leak nor stomal stenosis occurred, acute ileus occurred in 2 cases, and both recovered after the treatments of gastrointestinal decompression, inhibition of secretion digestive juice and reoperation. Acute retension of urine occurred in 1 case after urine catheter removed. The symptoms disappeared after excises of bladder function. These cases were followed up for 3-36 months (mean 20 months). All the patients recovered to normal function of defecation. Conclusion The technical keypoints of the second-phase diaplasis treatment after Hartmann operation are how to find and liberate the end of the distal colon. It will affect the prognosis and the occurrence of complications after this operation.
Red blood cells are destroyed when the shear stress in the blood pump exceeds a threshold, which in turn triggers hemolysis in the patient. The impeller design of centrifugal blood pumps significantly influences the hydraulic characteristics and hemolytic properties of these devices. Based on this premise, the present study employs a multiphase flow approach to numerically simulate centrifugal blood pumps, investigating the performance of pumps with varying numbers of blades and blade deflection angles. This analysis encompassed the examination of flow field characteristics, hydraulic performance, and hemolytic potential. Numerical results indicated that the concentration of red blood cells and elevated shear stresses primarily occurred at the impeller and volute tongue, which drastically increased the risk of hemolysis in these areas. It was found that increasing the number of blades within a certain range enhanced the hydraulic performance of the pump but also raised the potential for hemolysis. Moreover, augmenting the blade deflection angle could improve the hemolytic performance, particularly in pumps with a higher number of blades. The findings from this study can provide valuable insights for the structural improvement and performance enhancement of centrifugal blood pumps.
Objective To analyze the reasons for the perioperative death of endovascular repair of acute aortic dissection （AD）. Methods The clinical data of 176 patients with acute AD and received endovascular repair from July 2001 to October 2012 were analyzed retrospectively. Results Among 176 patients with acute AD， 8 patients died during perioperatively， received endovascular repair in 1-5 days after admission （mean 2.4 d）， and all of them admitted before 2008. Two cases were type A and 6 cases were type B. All cases with hypertension and 3 cases with pleural effusion. Three cases died on the day of operation， among them 2 cases occurred in 1 h after operation， the other 1 case occurred in 2 h after operation. Four cases died in 2 days after operation and 1 case died in 4 days after operation. Four cases died of rupture of the aortic dissection， 2 cases died of cerebral infarction， 1 case died of multiple organ failure， and 1 case died of gastrointestinal bleeding. Conclusion To avoid performing endovascular repair during the acute phase and improving operation skills may help to avoid the occurrence of perioperative death.
Wearing transfemoral prosthesis is the only way to complete daily physical activity for amputees. Motion pattern recognition is important for the control of prosthesis, especially in the recognizing swing phase and stance phase. In this paper, it is reported that surface electromyography (sEMG) signal is used in swing and stance phase recognition. sEMG signal of related muscles was sampled by Infiniti of a Canadian company. The sEMG signal was then filtered by weighted filtering window and analyzed by height permitted window. The starting time of stance phase and swing phase is determined through analyzing special muscles. The sEMG signal of rectus femoris was used in stance phase recognition and sEMG signal of tibialis anterior is used in swing phase recognition. In a certain tolerating range, the double windows theory, including weighted filtering window and height permitted window, can reach a high accuracy rate. Through experiments, the real walking consciousness of the people was reflected by sEMG signal of related muscles. Using related muscles to recognize swing and stance phase is reachable. The theory used in this paper is useful for analyzing sEMG signal and actual prosthesis control.
This study was aimed to improve the sensitivity of magnetic induction phase shift detection system for cerebral hemorrhage. In the study, a cerebral hemorrhage model with 13 rabbits was established by injection of autologous blood and the cerebral hemorrhage was detected by utilizing magnetic induction phase shift spectroscopy (MIPSS) detection method under the feature band. Sixty five groups of phase shift spectroscopy data were obtained. According to the characteristics of cerebral hemorrhage phase shift spectroscopy under the feature band, an effective method, B-F distribution, to diagnose the severity of cerebral hemorrhage was designed. The results showed that using MIPSS detection method under feature band, the phase shift obviously growed with increase of injection volume of autologous blood, and the phase shift induced by a 3-mL injection reached-7.750 3°±1.420 4°. B-F distribution could effectively diagnose the severity of cerebral hemorrhage. It can be concluded that the sensitivity of the cerebral hemorrhage magnetic induction detection system is improved by one order of magnitude with the MIPSS detection method under the feature band.
To better use the phase information to compensate the influence of blood flow, the phase unwrapping problem in susceptibility weighted imaging (SWI) is studied in this paper. In order to improve the accuracy of unwrapping, this paper proposes a magnitude image-guided phase unwrapping algorithm of SWI. The basic idea is as follows: (1) reduce the influence of noise by improving the rotational invariant non-local principal component analysis method (PRI-NL-PCA); (2) extract the corresponding solid region in the phase image to avoid the influence of the background noise on the phase unwrapping method; (3) use the phase compensation method to constrain the phase image reconstructed by the K-space. Finally, the reliability of the unwrapping method is evaluated by using four kinds of statistics as quantification index: the number, mean (M), variance (Var), and positive percentage (Pos) and negative percentage (Neg) of phasic error points. By comparing the simulated data with 226 sets of true head SWI data, the results show that the proposed algorithm has high accuracy compared with the classical branch cut method and the least squares method.