Objective To establish a better method of isolating andculturing ofneural stem cells(NSCs) in neonatal rat brain. Methods Tissue of brain was isolated from neonatal rats. Different medium and culture concentration were used toculture NSCs of neonatal rat. The culture concentration used were 1×10 4, 1×105, 1×106and 1×107/ml respectively. Ingredient of medium was classified into group 1 to 8 respectively according to whether to add 2% B27, epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) as well as the difference in culture concentration. The cells were induced to differentiate asto be confirmed as NSCs, and then were checked by phase contrast microscopy and identified by immunocytochemistry. Results The cells isolated and cultured gathered into neurospheres. The cells were capable of proliferating and maintaining longterm survival in vitro. The cells could be differentiated into neurons and glia.It was to the benefit of the survival of NSCs to add 5% fetal bovine serum(FBS)into the medium at the beginning of the culturing. When 10% FBS was added intothe medium, the neurospheres differentiated quickly. When concentration 1×106/ ml was used, the growth rate of the cells was the highest of all the concentrations. Reasonably higher cell concentration promoted the proliferation of NSCs. It was necessary to add 2% B27, EGF, and bFGF into the medium. The cells had the best growth when 2% B27, 20 ng/ml bFGF and 20 ng/ml EGF were added into the culture medium. EGF and bFGF had cooperative effect. Conclusion A better method of isolating and culturing of NSCs in neonatal rat brain is established and the foundation for future research is laid.
ObjectiveTo observe the effects of human umbilical cord mesenchymal stem cells (hUCMSCs) on blood glucose levels and diabetic retinopathy in diabetes mellitus (DM) rats. MethodA total of 45 healthy male Sprague-Dawley rats were randomly divided into normal control group (group A, 10 rats) and DM group (33 rats). Diabetic model was established in DM group by tail vein injection of streptozotocin.The DM group was further randomly divided into 3 groups (11 rats in each group), including group B (no transplantation), group C (hUCMSC was injected through tail vein) and group D (hUCMSC was injected into the vitreous). Blood glucose, retina wholemont staining and expression of brain derived neurotrophic factor (BDNF) in the retina were measured at 2, 4, 6, 8 weeks after hUCMSC injection. The blood glucose was significantly different between A-D groups before injection (t=-64.400, -60.601, -44.065, -43.872; P=0.000) BDNF expression was studied by real time fluorescence quantitative polymerase chain reaction (RT-PCR) and immunohistochemistry staining. ResultsThe blood glucose was significantly different between A-D groups after hUCMSC injection (F=400.017, 404.410, 422.043, 344.109; P=0.000), and between group C and group B/D (t=4.447, 4.990; P < 0.01). Immuno-staining shown that BDNF was positive in ganglion cell layer (RGC) of group A, weak in group B while BDNF expression increased in group C/D. BDNF mRNA expression was significantly different between group B, C and D at 4, 6 and 8 weeks after hUCMSC injection (F=29.372, 188.492, 421.537; P=0.000), and between group B and C/D (t=66.781, 72.401, 63.880, 88.423, 75.120, 83.002; P < 0.01) by RT-PCR analysis. The BDNF mRNA expression was significantly different between C and D groups only at 8 weeks after hUCMSC injection (t=127.321, P=0.005). ConclusionsTail vein injection of hUCMSCs can significantly reduce the blood glucose levels of rats. Intravenous and intravitreal injection of hUCMSCs can increase the expression of BDNF.
Transcranial magnetic stimulation (TMS), a widely used neuroregulatory technique, has been proven to be effective in treating neurological and psychiatric disorders. The therapeutic effect is closely related to the intracranial electric field caused by TMS, thus accurate measurement of the intracranial electric field generated by TMS is of great significance. However, direct intracranial measurement in human brain faces various technical, safety, ethical and other limitations. Therefore, we have constructed a brain phantom that can simulate the electrical conductivity and anatomical structure of the real brain, in order to replace the clinical trial to achieve intracranial electric field measurement. We selected and prepared suitable conductive materials based on the electrical conductivity of various layers of the real brain tissue, and performed image segmentation, three-dimensional reconstruction and three-dimensional printing processes on each layer of tissue based on magnetic resonance images. The production of each layer of tissue in the brain phantom was completed, and each layer of tissue was combined to form a complete brain phantom. The induced electric field generated by the TMS coil applied to the brain phantom was measured to further verify the conductivity of the brain phantom. Our study provides an effective experimental tool for studying the distribution of intracranial electric fields caused by TMS.
Objective To summarize the clinical experience of harvesting the lung of a brain death donor by international standardized methods, so as to establ ish a set of standards and regulations appl icable for harvesting the lung of brain-death donors in China. Methods The operation was performed on 1 brain-death donor who had endured 50 hours of mechanical ventilation. The donor was assessed by donor lung function test and international brain death standard. Then the organ was perfused and trimmed ready for lung transplantation. Results We succeeded in harvesting the heart, lung, liver, kidney and cornea from this brain-death voluntary donor. The harvested lung was successfully transplanted into a recipient. And the recipient recovered well after operation. Conclusion The successful experience of harvesting the lung of the brain-death voluntary donor will contribute to the development and promotion of the utilization of brain-death donor suppl ies.
Objective To investigate the effects of ginkgo biloba extract （GBE） on expressions of IL-1β, IL-6,and TNF-α in the pancreas and brain tissues of rats with severe acute pancreatitis （SAP）, and further to explore the pathogenesis of SAP and the efficacy of GBE on brain injury. Methods Fifty-four Winstar rats were randomly divided into normal control group, model group, and treatment group, with 18 rats for each group. For rats in the normal control group, only conversion of pancreas was performed by abdomen opening , followed by wound closure immediately. For rats in the model group and treatment group, 5% sodium taurocholate hydrate were injected under pancreatic capsule to establish SAP model, and then GBE and normal saline were infected into intra-abdomen repeatedly every 8 hours, respectively. At 6 h, 12 h, and 24 h after the model establishment, experimental samples were extracted and serum amylase was detected. Pathogenic scoring for pancreas tissues was performed under light microscopy, and immunohistochemistry method was employed to detect the expression levels of IL-1β, IL-6, and TNF-α in pancreas and brain tissues. Results For the treatment group, both serum amylase and pancreas scoring were significantly lower than those of the model group （P＜0.01）. At 24 h after model establishment, the expressions of IL-1β, IL-6, and TNF-α of pancreas tissues in model group were significantly higher than those at 6 h and 12 h （P＜0.05 or P＜0.01）, but no significant differences wereobserved in treatment group （P＞0.05）. The expressions of IL-1β, IL-6, and TNF-α of brain tissues in model group were significantly higher than those at 6 h and 12 h （P＜0.05 or P＜0.01）, but in treatment group decreased （P＜0.05 or P＜0.01）. The expressions of IL-1β, IL-6, and TNF-α in the treatment group were significantly lower than those of the model group at same time （P＜0.01）. Conclusions During SAP, the expressions of IL-1β, IL-6 and TNF-α in pancreas and brain tissues increased obviously. GBE showed suppressing and scavenging effects on IL-1β, IL-6 and TNF-α in pancreas and brain tissues.
Objective To investigate the perioperative changes of serum brain natriuretic peptide (BNP) concentrations in patients undergoing cardiac valve replacement. Methods There were 20 patients admitted to the study, the serum BNP concentrations were measured before cardiac surgery, 24 hours, 7days, 14 days, and 30 days after operation. The preoperative NYHA cardiac function and the left ventricular ejection fraction(LVEF) were measured by echocardiogram. Results The preoperative BNP level was the baseline, it elevated markedly and acutely to a peak value 24 hours after operation ( P =0.003), then the BNP decreased 7 days later, but was still higher than the concentration before operation ( P =0.015), 14 days later it reached to the concentration before operation, 30 days later it was mild lower than preoperative BNP level, but there was no significant difference. There was a positive correlation between NYHA and BNP ( r =0.69, P lt;0.05), but no correlation between LVEF and BNP( r =0.29, P gt;0 05). Conclusion The preoperative serum BNP concentration can reflect the preoperative cardiac function in patients undergoing cardiac valve replacement, the high BNP level indicates the poor cardiac function. The BNP sharply elevated in the early time after operation, then gradually decreased in the late phase postoperation.
OBJCTIVE :To investigate the fundus ocu]i changes in hypnxie isehemic encepbalnpa ally(HIE)of new[x,rns. METHODS:One hundred and two newblt;~rns suffered from HIE were investi- gated to observe lhe pathological neular fundus changes by di~et ophthabnoseopy after mydria~s. RE- SULTS:Seventy seven ca.~s(154 eyes)were found to have ophthalmoscopic changes in the ~ular fundi including papilledema .white retina vaseolar abnormality and hemorrhage. CONCLUSIONS:In clinical view .the severity of HIE depends on the pathological ebanges of the brain .and ftmdus ahnormalby will be very often in middle and .~vere sufforers of HIE.
Objective To set up and to evaluate an acute closed brain injury model in rats. Methods The acute closed brain injury was produced in rats by using an impactor consisting of a stand, a guide tube, a weight and a footplate. Ninetysix SD rats were divided into a control group(n＝32, no impact), a mild injury group(n＝32, impact once at force level of 400 g·cm) and a severe injury group(n＝32, impact once at force level of 800 g·cm) to elucidate the physiological responses, the pathophysiological changes and brain edema after brain injury at different injury levels. Results In the mild injury group and the severe injury group, a sudden rise or reduction of blood pressure, deep and fast breath apnea, and pain reflects inhibition were observed. The responses were more obvious in the severe injury group than in the mild injury group. The water content of the brain increased after 6 hours of injury. The pathological contusion and edema of brain were noted or above the impact force level of 800 g·cm. When the impact force rose to or over 1200g·cm, the animals died of persistent apnea mostly. Conclusion Although the established closed brain injury model with different biomechanical mechanisms as the clinical brain injury, it is in conformity with pathological changes and pathophysiological characteristics of acute clinical brain injury, it can be utilized extensively because of its convenient and practice.
Coding with high-frequency stimuli could alleviate the visual fatigue of users generated by the brain-computer interface (BCI) based on steady-state visual evoked potential (SSVEP). It would improve the comfort and safety of the system and has promising applications. However, most of the current advanced SSVEP decoding algorithms were compared and verified on low-frequency SSVEP datasets, and their recognition performance on high-frequency SSVEPs was still unknown. To address the aforementioned issue, electroencephalogram (EEG) data from 20 subjects were collected utilizing a high-frequency SSVEP paradigm. Then, the state-of-the-art SSVEP algorithms were compared, including 2 canonical correlation analysis algorithms, 3 task-related component analysis algorithms, and 1 task discriminant component analysis algorithm. The results indicated that they all could effectively decode high-frequency SSVEPs. Besides, there were differences in the classification performance and algorithms' speed under different conditions. This paper provides a basis for the selection of algorithms for high-frequency SSVEP-BCI, demonstrating its potential utility in developing user-friendly BCI.
Fifteen rabbits were given a second degree scald on the back, then a large amount of fluid were given rapidly. In this way an acute diluted hyponatremia and a brain edema model were produced. In one group, the magnetotherapy was instituted immediately following the acut injury, while in the other group, it was started after the brain edema being developed. After giving a large quantity of fluid, the Na~+, CI~-, and K~+ concentrations in the blood were decreased and the quantity of water in the brain tissue was increased evidentely. The phenomena of neuron edema and widening of the perivascular space were also found. It was proved that the model of experimental brain edema could be produced on animals and the treatment and the prevention for brain edema could be obtained to advantage to certaiin degree. Also,it was better to use the magnetotherapy in brain edema as early as possidle.