The main magnetic field, generated by the excitation coil of the magnetic induction phase shift technology detection system, is mostly dispersed field with small field strength, and the offset effect needs to be further improved, which makes the detection signal weak and the detection system difficult to achieve quantitative detection, thus the technology is rarely used in vivo experiments and clinical trials. In order to improve problems mentioned above, a new Helmholtz birdcage sensor was designed. Stimulation experiment was carried out to analyze the main magnetic field in aspects of intensity and magnetic distribution, then different bleeding volume and bleeding rates experiments were conducted to compared with traditional sensors. The results showed that magnetic field intensity in detection region was 2.5 times than that of traditional sensors, cancellation effect of the main magnetic field was achieved, the mean value of phase difference of 10 mL rabbit blood was (–3.34 ± 0.21)°, and exponential fitting adjusted R2 between phase difference and bleeding volumes and bleeding rates were both 0.99. The proposed Helmholtz birdcage sensor has a uniform magnetic field with a higher field strength, enable more accurate quantification of hemorrhage and monitored change of bleeding rates, providing significance in magnetic induced technology research for cerebral hemorrhage detection.
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.
Objective To investigate the mediating effect of phase angle between muscle strength and muscle function in maintenance hemodialysis (MHD) patients, aiming to provide a reference basis for clinical improvement of muscle strength and muscle function in MHD patients. Methods Random sampling was used to collect patients undergoing outpatient MHD in the Wenjiang Hemodialysis Room of the Department of Nephrology, West China Hospital, Sichuan University between September and December 2023 as the subjects of this study. Muscle strength was assessed by handgrip strength, muscle function was assessed by Short Physical Performance Battery (SPPB), and phase angle was measured by bioelectrical impedance analysis. The mediating effect of phase angle between muscle strength and muscle function was analyzed. Results A total of 239 MHD patients were included, including 125 males (52.3%) and 114 females (47.7%). The mean phase angle of MHD patients was (5.77±1.17)°, 89 patients (37.2%) showed decreased muscle strength, and 109 patients (45.6%) showed muscle hypoplasia. Spearman’s correlation analyses showed that phase angle was significantly and positively correlated with both handgrip strength and SPPB in MHD patients (P<0.001). The results of mediation effect analysis showed that handgrip strength was able to positively predict phase angle (β=0.535, P<0.001); handgrip strength was able to positively predict SPPB (β=0.481, P<0.001); phase angle was able to positively predict SPPB (β=0.296, P<0.001); and when both handgrip strength and phase angle entered in the regression equation, both handgrip strength (β=0.392, P<0.001) and phase angle (β=0.165, P<0.05) could positively predict SPPB. Phase angle in MHD patients partially mediated the association between muscle strength and muscle function, with the mediating effect accounting for 32.5% of the total effect. Conclusions There is a close relationship between phase angle, muscle strength and muscle function in MHD patients, and muscle strength can affect muscle function directly or indirectly through phase angle. Medical professionals should pay attention to the muscle function of MHD patients and further improve their muscle function by improving their phase angle and muscle strength.
Objective To study the expressions of SKP2 and p27 in gastric carcinoma and pericancerous tissues and to detect the relationship between their expressions and clinicopathological features. Methods Forty-nine cases of gastric carcinoma spicemen and 20 cases of tissue adjacent to the carcinoma were cut and made into paraffin-embedded slices. The expressions of SKP2 and p27 were then detected by SP immunohistochemical method. Results The positive expression rate and score of SKP2 were both significantly higher in the gastric carcinoma tissues than those in pericancerous tissues (P＜0.01), whereas those terms of p27 were higher in pericancerous tissues (P＜0.05, P＜0.01). It was observed that the pericancerous tissues with positive SKP2 expression or with negative p27 expression showed atypical hyperplasis ranging from moderate to severe degrees. The positive rate and score of SKP2 were significantly lower in the cases of infiltrating depth T1+T2， without-metastasis of lymph node, with-metastasis of the first site lymph node, and without-metastasis of distant organs than those in infiltrating depth T3+T4, with-metastasis of lymph node, with-metastasis of the second or third site lymph node and with-metastasis of distant organs in gastric carcinoma tissues (P＜0.05， P＜0.01), whereas the results were contrary for p27 (P＜0.01). There was a negative correlation between the score of SKP2 and that of p27 in gastric carcinoma tissues (r=-0.65, P＜0.01). Conclusion The expressions of SKP2 and p27 may act as important biological markers to reflect carcinogenesis, progression, biological beheviors and prognosis of gastric carcinoma.
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.
ObjectiveTo observe systemic inflammatory response (SIR)of patients in different stages after the onset of aortic dissection (AD), and preliminarily explore a new staging system of AD based on SIR. MethodsFrom September 2011 to February 2012, 46 AD patients were admitted to the Department of Cardiovascular Surgery, West China Hospital of Sichuan University. There were 33 male and 13 female patients with their age ranging from 22 to 77 years (53.2±13.6 years). Blood samples were collected in 9 different periods after the onset of AD (0-12 hours (T1), 12-24 hours (T2), 24-48 hours (T3, 1-2 days), 48-96 hours (T4, 2-4 days), 96-168 hours (T5, 4-7 days), 168-336 hours (T6, 7-14 days), 336-720 hours (T7, 14-30 days), 720-1440 hours (T8, 30-60 days) and > 1 440 hours (T9, > days))to measure blood concentrations of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), endotoxin (ET), white blood cell (WBC)and neutrophils (Neut). SIR changes after the onset of AD were summarized. ResultsBlood concentrations of different inflammatory mediators were all significantly elevated within 14 days (T1-T6), significantly decreased in 14-60 days (T7-T8), and returned to normal range 60 days (T9)after the onset of AD. Peak levels of ET and TNF-α appeared in T1 with 263.42±29.98 pg/ml and 86.75±18.83 pg/ml respectively. Peak level of IL-6 appeared in T2 with 95.70±22.64 pg/ml. Peak level of CRP appeared in T5 with 123.74±54.78 mg/L. There was no obvious peak level of WBC or Neut. ConclusionDisease progression of AD can be divided into 3 stages including acute stage (within 14 days), subacute stage (14-60 days)and chronic stage ( > 60 days)based on the degree of SIR.
ObjectiveTo compare curative effect of catheter drainage following ultrasound-guided vacuum-assisted rotary excision and traditional excision in treatment of granulomatous mastitis in abscess stage. MethodsA total of 38 patients with granulomatous mastitis in abscess phase from December 2016 to March 2017 in the Third People’s Hospital of Chengdu City and from March 2017 to October 2017 in the Sichuan Provincial Hospital for Women and Children were included as a study group, who were received the catheter drainage following ultrasound-guided vacuum-assisted rotary excision. A total of 38 similar cases from July 2015 to November 2016 in the Third People’s Hospital of Chengdu City were collected as a control group according to the 1∶1 matching principle, who were received the traditional excision. The therapeutic period, postoperative appearance of breast, and recurrence rate were compared between these two groups. ResultsCompared with the control group, the therapeutic period was significantly shorter (t=74.000, P<0.001), the postoperative appearance of breast was significantly better (χ2=7.280, P=0.007) in the study group, while the recurrence rate had no significant difference (χ2=0.559, P=0.455) between these two groups. ConclusionsCatheter drainage following ultrasound-guided vacuum-assisted rotary excision shows advantages in postoperative therapeutic period and appearance of breast and doesn’t increase relapse rate as compared with traditional surgery for patients with granulomatous mastitis in abscess stage.
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 main reason of prolonged latency phase and the impact of prolonged latency phase on the delivery style. Methods The pregnant women with prolonged latency phase (n=92) and normal pregnant women (n=100) were retrospectively analyzed in the maternity department of the second affiliated hospital of Kunming medical college in 2007. Results There was no significant difference in the pelvis and fetal-pelvis in the two groups. The number of the pregnant women with fetal body weight (gt;4 000 g) in the prolonged latency phase group was obviously larger than that in the normal pregnant women group, with the significant difference. As to the situation of fetal position, there were more occipitoanterior positions and fewer occipitoposterior as well as occipitotransterse positions in the prolonged latency phase group (Plt;0.01). In the prolonged latency phase group, the pregnant women with normal delivery were fewer and the uterine-incision deliveries were more than those in the normal group, with the significant difference. Conclusion The prolonged latency phase prognosticates the incidence of dystocia. We should decide if the pregnant women have the tendency of prolonged latency phase before delivery and deal with it in time so as to prevent the occurrence of dystocia.
The real-time monitoring of cerebral hemorrhage can reduce its disability and fatality rates greatly. On the basis of magnetic induction phase shift, we in this study used filter and amplifier hardware module, NI-PXI data-acquisition system and LabVIEW software to set up an experiment system. We used Band-pass sample method and correlation phase demodulation algorithm in the system. In order to test and evaluate the performance of the system, we carried out saline simulation experiments of brain hemorrhage. We also carried out rabbit cerebral hemorrhage experiments. The results of both saline simulation and animal experiments suggested that our monitoring system had a high phase detection precision, and it needed only about 0.030 4s to finish a single phase shift measurement, and the change of phase shift was directly proportional to the volume of saline or blood. The experimental results were consistent with theory. As a result, this system has the ability of real-time monitoring the progression of cerebral hemorrhage precisely, with many distinguished features, such as low cost, high phase detection precision, high sensitivity of response so that it has showed a good application prospect.