BACKGROUND: Due to a new finding in the in vitro proliferation and differentiation of neural stem cells, neural stem cells are regarded as optimal materials for repairing and replacing the injured neural tissues. But how to enhance the proliferation of neural stem cells and how to induce neural stem cells to differentiate into certain phenotypes remain objects for discussing.OBJECTIVE: To investigate the frozen/nonfrozen storage techniques in isolation and cultivation of neural stem cells isolated from human brain and to discuss the conditions suitable for their differentiation.DESIGN: A single sample based on cells.SETTING: Urinology Institute of Jiangxi Medical University and Neurosurgery Department of Second Hospital Affiliated to Jiangxi Medical College.MATERIALS: From December 2003 to June 2004, this study was conducted at the Urinology Institute of Jiangxi Medical College. Brain tissues removed from sixteen-week-old embryos were studied.METHODS: After being digested with trypsin, cells were separated from the brains of embryos. They were cultured in the serum-free media, stimulated by basic fibroblast growth factor and epidermal growth factor and were induced to differentiate using serum. Immunofluorescent cytochemical staining technique was adopted to detect the expressions of the Nestin and the neuron-specific enolase(the marker for mature neural cells) in these cells. The influence of basic fibroblast growth factor, epidermal growth factor and serum on the proliferation and differentiation of the neural stem cells were investigated.MAIN OUTCOME MEASURES: The main outcome measurements in this tification of the Nestin and the neuron-specific enolase in these cells.bryo brain successfully. The embryo brain cells in primary culture were clear and round. After 3 days some cells aggregated to form neurospheres and some others suspended. Two weeks later, the neurospheres enlarged and a part of cells in it expanded into folds with strong reflection and proliferation. The continuous cultured cells inherited these characteristics and kept the morphological properties. The clones were cultured in the medium with serum. Twenty-four hours later, most of the cells were attached to the bottom of the plates. Cells were dissociated from the neurospheres and became irregular. Forty-eight hours later, most of the cells differentiated into many scattered patches of astrocytes with various shapes and neurites and many isolated neural stem cells were continuously cultured in vitro and they expressed Nestin, the marker of neural stem cells. After being cultured in medium with serum for 48 hours, the differentiated cells mainly expressed freeze-thaw cells were alive. Their living status had no significant difference compared to that of the fresh isolated cells.CONCLUSION: Serum-free culture medium, together with basic fibroblast growth factor and epidermal growth factor, enables the in vitro culture, proliferation and purification of the neural stem cells. The feasibility of the method is confirmed. Meanwhile, the comparison between the cultures of freeze-thaw cells and fresh isolated cells indicated that frozen storage can be used as a way to preserve the human embryo brain cells, which will be available for study after thaw.

Objective To review the treatment of repair gastroschisis with autogenous umbilical cord and evaluate its effect. Methods Thirty newborns who underwent the repair gastroschisis with autogenous umbilical cord between August 1992 to October 2007, 26 cases survived under observed and followed-up, observing physical growth, intelligence measuring and whether the area of operated in abdomen need staged repair or not. Compared with 15 cases who underwent traditional operation method at the same time. Results Two cases died, 2 cases abandoned, and 26 ease received survive (survive rate 86.7%)and their growth was well in 26 cases. But in those 15 cases who underwent traditional operation method, 5 cases survived (survive rate 33.3%). There were significant difference in the survive rate, the mean operative time and postoperative hospital stay time between the two operation methods (P <0.05).Conclusion The material is adopted easily in the operation, autogenous umbilical cord is elastic tissue and no toxicity, it can relax the abdominal press effectively after the operation, the survive rate is high.

BACKGROUND: Earthworms are one of the most important constituents in the ecosystem and become an environmental information carrier between terrestrial organisms and soil ecosystem. They were known as important non-target terrestrial soil organisms for assessing the general impact of pollution on the soil community. Protein content and growth rate in response to organic and heavy metal contaminants in soil are often used to assess the soil ecotoxicity.OBJECTIVES: To investigate the effects of 1, 8-dihydroxyanthraquinone,one representative of hydroxyanthraquinones, on the earthworm eisenia foetide under laboratory conditions of the growth rate and protein content.DESIGN: Experimental study based on the experimental animals.SETTING: Eco-toxicological laboratory and genetic laboratory in a university.MATERIALS: The experiment was conducted in the Eco-toxicological Laboratory and the Genetic Laboratory, Dalian University of Technology from February to July 2004. Eisenia foetide, a kind of international standard earthworm, were maintained in a soil mixture before experiments. Earthworms used in this study were healthy adults with 1 -2 month old and 200 - 300 mg mass and the number of the earthworms in each analytical experiment was 10.METHODS: The earthworms were removed from the soil 12 hours before use and stored in Petri dishes on damp filter paper to void gut contents.Then, these earthworms were exposed for various durations to soils contaminated. The earthworm weight and protein content were determined respectively at every 7 days interval.MAIN OUTCOME MEASURES: Effects of 1, 8-dihydroxyanthraquinone on growth rate and protein content of earthworms.RESULTS: No lethal effect of 1, 8-dihydroxyanthraquinone was observed even at the highest concentration(1.0 g/kg soil) of exposure. The sub-lethal effect, however, was evident at all the concentration scale. 1,8-dihydroxyanthraquinone caused a significant reduction in the growth rate (maximum -22. 5% ) at the dosage of 1.0 g/kg and 28 days contact time.Additionally a reduction in total soluble protein was observed in all treated worms(maximum- 39.6% ) at the dosage of 0. 8 g/kg and 7 days contact time.CONCLUSION: 1, 8-dihydroxyanthraquinone was potentially dangerous to the soil ecosystem and more ecological risk assessment of this chemical material should be thoroughly carried out.

BACKGROUND: Bone marrow cell transplantation is a simple and effective treatment to promote angiogenesis. The neovascularization and reestablishment of blood circulation is crucial to the repair of injured but still living neurons as well as to the survival and differentiation of the implanted tissues and cells. However,it is not clearly known whether autologous bone marrow cells implantation could promote neovascularization and facilitate reestablishment of circulation in ischemic regions of the brain.OBJECTIVE: To investigate the effect of autologous bone marrow cell transplantation via the carotid artery on angiogenesis in the ischemic regions of the brain.DESIGN: A randomized controlled experiment based on experimental animals.SETTING: Department of neurosurgery and institute of urinary surgery in a university hospital.MATERIALS: The experiment was conducted in the Laboratory of the Department of Neurosurgery,Second Affiliated Hospital,and the Institute of Urinary Surgery,Jiangxi Medical College during the period from September 2002 to April 2003,using 10 specific pathogen-free male SD rats weighing 250 - 300 g.INTERVENTIONS: Rat models of focal cerebral ischemia model were established and randomized equally into two groups. The rats in the transplantation group were injected with autologous bone marrow cells via the carotid artery and those in the control group normal saline injection. The angiogenesis in the ischemic regions of the brain was observed with immunohistochemical staining for microvessel counting.MAIN OUTCOME MEASURES: The density of microvessels. Immunohistochemical staining for F8.RESULTS: Greater density of the microvessels was found in the ischemic regions after bone marrow cell transplantation than in the control group[(159. 15 ±40.4)/mm2 vs(81.70 ± 32. 18)/mm2,P ＜ 0. 05] . Numerous endothelial cells were found scattered in the ischemic cortex of the transplantation group,but scarcely in the control group.CONCLUSION: Autologous bone marrow cell transplantation via the carotid artery can promote angiogenesis in the ischemic regions of the brain.

Objective To analyze the setup errors of external?beam and intracavitary radiotherapy for cervical cancer based on the data of cone?beam computed tomography ( CBCT) , and to provide a basis for clinical practice. Methods Sixty patients with stage ⅡA?ⅢB cervical cancer who were admitted to our hospital and underwent external?beam and intracavitary radiotherapy from March to June, 2015 were enrolled as subjects. Sixty patients with stage ⅡA?ⅢB cervical cancer undergoing conventional external?beam radiotherapy within the same period were also enrolled. The CBCT?based setup errors, containing setup errors in x, y, and z directions and three?dimensional vector deviation, in the initial treatment were obtained from each patient. Comparison of errors between the two treatment approaches was made by independent?samples t test. Results Fitting the data to a linear model revealed that the setup errors in x, y, and z directions increased with the increase in the distance between the position reference point and the center point of the target volume. External?beam radiation combined with intracavitary radiation had significantly reduced setup errors in x, y, and z directions than the conventional external?beam radiation ( 0.13± 0?12 vs. 0.31± 0?24, P=0?000;0.23±0?18 vs. 0.47±0?36, P=0?001;0.18±0?11 vs. 0.27±0?18, P=0?001). Conclusions In order to reduce the setup errors, CT scan needs not only a reference marker as close as possible to the center of the tumor, but also a reliable and accurate approach for postural fixation.

Objective To investigate the correlation between the measurement methods of carotidcerebral pulse wave velocity (ccPWV) and the traditional method of brachial-ankle pulse wave velocity (baPWV).Methods A total of 136 healthy volunteers were divided into a youth group (20-39 years),a middleaged group (40-59 years),and an elderly group (more than 60 years) according to their ages.While detecting baPWV,transcranial Doppler ultrasound was used to simultaneously monitor the ipsilateral common carotid artery and the terminal segment of internal carotid artery.The time differences of the beating points of their cardiac cycles and the distanceses of the skin surfaces between the 2 probes were measured and ccPWV was calculated.Results The systolic blood pressure,pulse pressure and mean arterial pressure in the elderly group were signifificantly higher than those in the middle-aged group and the young group.The ccPWVs in the youth,middle-aged and elderly groups were 418 ± 52 cm/s,489 ±54 cm/s,and 599 ± 58 cm/s,respectively.The elderly group was significantly faster than the middle-aged group (t =7.308,P ＜0.001),and the middle-aged group was significantly faster than the youth group (t=6.758,P＜0.001).A Pearson correlation analysis showed that ccPWV was significantly positively associated with the age (r=0.847,P＜0.001) and baPWV (r =0.548,P ＜0.001).The multiple linear regression analysis showed that ccPWV was significantly positively associated with the age and diastolic blood pressure (partial correlation coefficients were 0.742 and 0.293respectively,P ＜0.001 and ＜0.010 respectively).Conchlusions ccPWV is a new measurement method for cerebrovascular stiffneas,and it has a good correlation with the traditional measurement method.

Human hepatocyte transplantation to treat liver-based metabolic deficiencies and acute liver failure has shown promising early improvement in liver function; however, long-term success has not been achieved. Stem cell transplantation to restore liver function as an alternative to whole liver transplantation has not been successful in humans. As alternative sources of cells for human hepatocyte transplantation, stem cells are under investigation. The liver extracellular matrix presents an ideal scaffold for stem cell differentiation into hepatocytes, as well as cell transplantation. The innovative technique of the decellularized liver matrix presents great potential as the scaffold for hepatocyte maturation and transplantation, and allows the development of engineered recellularized liver graft for transplantation.
Extracellular Matrix ; Hepatocytes ; transplantation ; Humans ; Liver Failure ; surgery ; Liver Regeneration ; Liver Transplantation ; methods ; Stem Cell Transplantation ; methods ; Tissue Engineering ; methods ; Tissue Scaffolds

Objective To develop double-arc volumetric modulated arc therapy ( VMAT) plans using standard phantom and standard target volume in AAPM119 report, and to investigate the dosimetric parameters of Agility and MLCi2 leafs according to the requirements for target dose in AAPM119 report. Methods The Cshape, Head and Neck, Prostate, and Multitarget structures for standard target volume delineation in AAPM119 report were used.The Elekta Agility multi-leaf collimator was used to develop plans, and then with other parameters remaining unchanged, Elekta MLCi2 was used for plan optimization and dose calculation.The target dose in AAPM119 report was used as the standard to analyze the differences in target volume and dose-volume parameters of organs at risk between the four structures for target volume delineation.Results According to the mean dose in AAPM119 report, in the Cshape, Head and Neck, and Multitarget target volumes, the radiotherapy plans developed with Agility had better dosimetric parameters compared with those developed with MLCi2.In the prostate target volume, the radiotherapy plans developed with MLCi 2 had better dosimetric parameters compared with those developed with Agility .Conclusions With the structures for target volume delineation, plan designing personnel, designing parameters, and evaluation criteria remaining the same, Elekta Agility can achieve the dose target better than Elekta MLCi2 in the aspect of strict dose limit.

The distribution of shear stress on the bottom of the parallel plate flow chamber under different inlet velocities was analyzed by numerical simulation. In the present experimental study, the projection planes of the relative errors at 0.7% level were obtained, and then the efficient region and the actual entrance length were further corrected by introducing the concept of relative error. The results showed that the efficient region of the chamber increased with the direction of length while the inlet velocity was increased, and the actual entrance length was much greater than that of the theoretical entrance length. Therefore, in accordance to the needed range of shear stress in experiment and to the needed efficient region area, the optimum design of the flow chamber is necessary.
Algorithms ; Blood Flow Velocity ; Blood Pressure ; physiology ; Computer Simulation ; Humans ; Models, Cardiovascular ; Numerical Analysis, Computer-Assisted ; Pulsatile Flow ; Rheology ; Shear Strength ; Stress, Mechanical

Objective:To explore the mediating role of self-control in the relationship between alexithymia and internet addiction.Methods:From August to September 2019, a total of 433 college students were selected from three universities in Jiangxi province by cluster random sampling method. The Chinese internet addiction scale-revised, the twenty-item Toronto alexithymia scale and brief self-control scale were used for questionnaire testing. SPSS 23.0 software was used for descriptive statistics, Pearson correlation analysis and PROCESS V3.5 macro program was used to test the mediating effect.Results:The total scores of alexithymia, internet addiction and self-control were (53.61±9.44), (45.31±9.84) and (41.91±6.09), respectively. Pearson correlation analysis showed that alexithymia was significantly positively correlated with internet addiction ( r=0.47, P<0.01), and significantly negatively correlated with self-control ( r=-0.37, P<0.01). The negative correlation between self-control and internet addiction was significant ( r=-0.46, P<0.01). Multivariate hierarchical regression analysis showed that alexithymia directly predicted internet addiction after controlling the influence of gender. Self-control played a partially mediating role in the relationship between alexithymia and internet addiction (effect size=0.13, 95% CI: 0.082-0.185), the mediating effect accounted for 25% of the total effect. Conclusion:Alexithymia not only directly affects college students′ internet addiction, but also indirectly affects college students′ internet addiction through self-control.