1.Preparation of titanium implant surface bioactive membrane
Chinese Journal of Tissue Engineering Research 2009;13(38):7489-7492
BACKGROUND: The coating induced by conventional simulated body fluid (SBF) and 1.5-folds SBF as biomimetic method has the shortcomings of slowly growth with weeks or months growth cycle. OBJECTIVE: To evaluate Ti-6Al-4V alloy surface deposition of hydroxyapatite coating induced by 3-folds SBF. DESIGN, TIME AND SETTING: In vitro biological analysis. The experiment was performed at the Institute of Metal Research, Chinese Academy of Sciences from November 2008 to March 2009. MATERIALS: Ti-6A1-4V alloy was supported by Boda Metel Materials Co., Ltd. METHODS: The pretreated Ti-6Al-4V alloy was immersed in 37 'C 3-folds SBF. The SBF was replaced every 24 hours for 3 days. MAIN OUTCOME MEASURES: The morphology, phase and elemental composition of calcium phosphate coating were analyzed by scanning electron microscopy, X-ray diffraction and infrared spectroscopy analysis. RESULTS: The scanning electron microscopy exhibited that the surface of Ti-6A1 -4V alloy was covered with deposited film with granular crystal on local areas at day 1 after immersion. The deposited film covered surface of Ti-6A1-4V alloy at day 3 after immersion, and granular or scale-shaped crystal could be seen. The crystal deposition displayed sustained growth with certain area as center. The product comprised Ca, P, O, C elements without Al, V. X-ray diffraction and infrared spectroscopy analysis revealed that the main component of the coating was hydroxyapatite. CONCLUSION: The 3-folds SBF can accelerate the deposition as well as shorten formation duration of hydroxyapatite coating on Ti-6A1-4V alloy.
2.Effects of desflurane on heart rate variability in patients at risk for coronary artery disease
Xiaoguang CHEN ; Junke WANG ; Xiaoguang ZHANG
Chinese Journal of Anesthesiology 1994;0(03):-
Objective To investigate the effect of desflurane anesthesia on the autonomic nervous system in patients at high risk for coronary artery disease.Methods Thirty patients at high risk for coronary artery disease scheduled for elective abdominal operation were selected. Heart rate variability (HRV) was assessed at preoperation, inhalation of 05,10,15 and 20 MAC of desflurane with Holter electrocardiography Results Low-frequency component increased markedly inhaling low concentration of desflurane. With the increase of the concentration of desflurane, both the high-frequency and low-frequency components decreased significantly (P0 05).Conclusions Desflurane balanced anesthesia dose not increase the activity of sympathetic nervous system.
3.Common etiology and pathogenesis of plastic bronchitis in children
Chinese Journal of Applied Clinical Pediatrics 2021;36(4):244-247
Plastic bronchitis(PB) is an uncommon respiratory disease characterized by formation of casts in tracheobronchial tree.It can lead to airway obstruction, difficulty of breathing and even respiratory failure.PB in children is commonly associated with lower airway infection, cyanotic congenital heart disease and asthma or atopic diseases.It can also be found in children with sickle cell anemia, thalassemia and cystic fibrosis and so no.There are three main mechanisms for the formation of casts: airway inflammation results in mucus hypersecretion; inflammatory insults lead to necrosis and abscission of the airway epithelium, mucosal edema, and finally cause airway clearance impairment; leakage of chyle from lung lymphatic circulation into airway.But the etiology of this disease is various, pathogenesis is complex.Further research is required to elucidate the pathogenesis.
5.Impact of tripterygium glycosides on the expression of CXCR3 and CCR4 genes in peripheral blood from experimental autoimmune thyroiditis rats
Xiaoguang XU ; Hong ZHANG ; Jun GU
Chinese Journal of Dermatology 2010;43(11):792-795
Objective To analyze the impact of tripterygium glycosides (TG) on the expression of CXCR3 and CCR4 gene in peripheral blood mononuclear cells from experimental autoimmune thyroiditis (EAT) rats, and to explore the possible mechanism for regulation of Th1/Th2 balance by TG. Methods EAT was induced in 20 rats, which were randomly divided into two groups, i.e., control group and TG group, to receive intragastric physiological saline and TG suspension (5.5 mg/kg) daily, respectively. The rats were killed 4weeks later, and total RNA was extracted from the peripheral blood mononuclear cells of rats and used for cRNA synthesis. The gene expressions of CXCR3 and CCR4 were detected with a Th1-Th2-Th3 microarray gene chip and realtime RT-PCR. Results Compared with the control group, there was a significant decrease in the mRNA expression of CXCR3 (0.52 ± 0.10 vs. 1.05 ± 0.17, P < 0.01 ) and CXCR3/CCR4 ratio (0.39 ± 0.22 vs. 1.04 ± 0.12, P< 0.01) in the TG group, together with an increase in the mRNA expression of CCR4 (1.56 ±0.13 vs. 1.02 ± 0.09, P < 0.01 ). Conclusions TG could regulate the number of Th1 and Th2 cells as well as their cytokine expression ratio likely by reducing CXCR3 and enhancing CCR4 expression, so as to modulate the Th1/Th2 balance in EAT rats.
6.Dentoalveolar and skeletal changes consequent to maxillary molar distalization with the modified pendulum appliance in classII malocclusion
Xiaoguang ZHANG ; Xuyan TANG ; Jun SHEN
Acta Universitatis Medicinalis Anhui 2014;(5):673-675
21 classII malocclusion adolescents (9 boys and 12 girls) were selected as the subjects, aged from 10.6 to 14.5 years, and the initial mean age was 12.8 years. All were treated with the modified Pendulum appli-ance. The duration for distalization of maxillary molars was from 3.2 to 5.7 months (4.3 months on average). Lat-eral cephalograms were obtained before and after distalization. Changes produced by the modified Pendulum appli-ance were analyzed with paired t tests. The mean space opening on lateral cephalograms was 7.31 mm, and maxil-lary first molar distalization accounted for 64.8% of the space,with a mean distal crown tipping of 18.64o. The rate of molar movement was 1.27 mm per month. The maxillary first molars intruded 0.69 mm,and the premolars extru-ded 1.02 mm. Lower anterior facial height increased 2.19 mm. The maxillary incisors had increased 3.39oof labial tipping and 1.13 mm of protrusion.
7.Impact of the method of cooling blood to remove stasis on tumor necrosis factor-alpha and interleukin-10 mRNA expressions in peripheral blood mononuclear cells of rats with experimental autoimmune thyroiditis
Hong ZHANG ; Xiaoguang XU ; Jun GU
Journal of Integrative Medicine 2008;6(2):190-3
OBJECTIVE: To explore the effects of Liangxue Huayu therapy (LXHYT), a traditional Chinese herbal therapy for cooling blood and dissipating blood stasis, on rat model of experimental autoimmune thyroiditis (EAT) and its impact on tumor necrosis factor-alpha and interleukin-10 mRNA expressions in peripheral blood mononuclear cells. METHODS: Forty Wistar rats were randomly divided into five groups: normal control group, untreated EAT group, cyclosporine A (CyA)-treated group, Tripterygium glycosides-treated group and Liangxue Huayu Recipe (LXHYR)-treated group. The interventions were given by gavage to the rats in different groups once a day. All rats were sacrificed after 4-week treatment, and the level of serum thyroglobulin antibodies (TgAb) and the changes of histological grade of thyroid specimen were assessed by blind evaluation. Expressions of tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10) mRNAs in peripheral blood mononuclear cells were assessed by real-time reverse transcription polymerase chain reaction method. RESULTS: There was a significant increase in the serum TgAb level and severe inflammatory infiltration in the untreated group. Expression of TNF-alpha mRNA in peripheral blood mononuclear cells was increased, while the expression of IL-10 mRNA was decreased in the untreated group (P<0.01). Compared with the untreated group, CyA, Tripterygium glycosides and LXHYF could decrease the serum TgAb level (P<0.05), but the three interventions showed no significant improvement in thyroid inflammation (P>0.05). TNF-alpha mRNA expression was decreased, while IL-10 mRNA expression was increased as compared with the untreated group (P<0.05). CONCLUSION: LXHYT can decrease the serum TgAb level and recover the balance of Th1/Th2. This may provide an experimental basis for further research of assessing the antipsoriatic effect of Chinese herbal drugs with a rat model of EAT as an alternative model of psoriasis in vivo.
8.Preparation and characterization of chitosan-g-poly (3-hydroxybutyrate) copolymer
Xiaorong MENG ; Xiaoguang YANG ; Min ZHANG
Chinese Journal of Tissue Engineering Research 2008;12(23):4591-4593
BACKGROUND: Chitosan/poly (3-hydroxybutyrate) (PHB) copolymer has been paid close attention for special biological source of Chitosan and PHB. However, there has been no proper method for them to polymerize effectively.OBJECTIVE: To prepare chitosan/PHB graft copolymer in a homogeneous medium, using a gentle initiator.DESIGN, TIME and SETTING: This study, a single-sample experiment, was performed at the Research Center of Chemistry, Xi'an University of Architecture and Technology, Xi'an, Shaanxi Province, China from August 2007 to October 2007.MATERIALS: Chitosan: DD=100%, Mη=123000, Kyoto, Japan. PHB was purchased from Aldrich chemicals and the molecular weight was 10000.METHODS: Chitosan was grafted with poly (3-hydroxybutyrate) (PHB) in acetic acid/dimethyl sulfoxide system, and benzoyl peroxide (BPO) was used as initiator. The reaction temperature was 85℃ and the reaction continued for 5 hours with nitrogen protection. Grafting reaction and the chemical structure of the copolymer were confirmed by infrared analysis, NMR and elemental analysis. The crystal form and thermal stability of copolymer were characterized with wide-angel X-ray diffraction (WAXD) and thermogravimetric/differential thermal analysis balance, respectively.MAIN OUTCOME MEASURES: The chemical structure of copolymer, crystal form as well as thermal stability.RESULTS: Grafting reaction was confirmed by infrared analysis, NMR and elemental analysis. Wide angle X-ray diffraction and thermogravimetric analysis indicated that graft copolymer was different from chitosan and PHB in crystalline morphology, and had a good thermal stability.CONCLUSION: Using BPO as initiator, chitosan/PHB grafting copolymer is prepared and it has a steady property.
9.Damaged PC12 cells in Transwell culture system for promoting the transdifferentiation of bone marrow stromal stem cells into neuron-like cells
Jin ZHOU ; Xiaoguang LUO ; Chaodong ZHANG
Chinese Journal of Tissue Engineering Research 2007;11(37):7481-7484
BACKGROUND: Drug treatment has unsatisfactory effect on Alzheimer disease, while many studies have indicated that the transplantation of bone marrow stromal cells (MSCs) is effective on Parkinson disease, cerebral ischemia, etc., but the mechanism is still unclear.OBJECTIVE: To imitate transplantation environment by co-culture of amyloid β1-40 (Aβ1-40) damaged PC12 cells and MSCs, observe the effect of bi-directional information feedback in the microenvironment on the transdifferentiation of MSCs to nerve cells, and observe its protective effect on the apoptosis of damaged PC12 cells.DESTGN: A comparative observation.SETTING: Department of Neurology, China Medical University.MATERIALS: SD rats of 2-3 weeks after birth either male or female were used. PC12 cell lines were purchased from the Institute of Cell Biology, Chinese Academy of Sciences; neuro-specific enolase (1:50, Boster, Wuhan);Methyl-thiazol-tetrazolium (MTT) 15 μL (terminal concentration of 0.5 g/L).METHODS: The experiment was carried out in the Experimental Center (provincial experimental animal center) of China Medical University from June to July in 2004. Bilateral femurs were aseptically removed from 1 SD rat, and MSCs were identified using CD44 antibody immunofiuorescently. PC12 was used to replace nerve cells. The PC12 cells were stimulated by Aβ1-40 then transferred by Transwell. There were 5 groups: Group A: normally cultured PC12 co-cultured with MSCs; Group B: Aβ1-40 stimulated PC12 co-cultured with MSCs; Group C: normal PC12 supernatant+MSCs; Group D: damaged PC12 supernatant+MSCs; Group E: MSCs cultured with common medium 1640.MAIN OUTCOME MEASURES:Routine immunohistochemical staining was performed. NSE positive cells were observed under inverted fluorescence microscope, 10 visual fields (200×) were randomly selected to count the positive cells. MTT metabolic rate was used to detect the proliferation of MSCs in each group. The differences of measurement data were compared using the one-way analysis of variance.fluorescent and bright fields, NSE positive cells appeared as red fluorescence, MSCs were bipolar, multipolar and cone shapes, and appeared as neuron-like forms with dendrite-like structure, and there were extensive connections among some neuron-like cells. The NSE positive rates was obviously higher in group B than groups A, C, D and E (P < 0.01 ).in groups A, C, D and E (F=9.713, P< 0.01).
10.Signal transduction of c-Jun N-terminal kinase against beta-amyloid protein 1-40 induced neuronal toxicity to cortical progenitor cells of embryonic rats
Rong YAN ; Xiaoguang LUO ; Chaodong ZHANG
Chinese Journal of Tissue Engineering Research 2006;10(17):170-173
BACKGROUND: The primary pathophysiology of Alzheimer disease (AD) is linked to β-amyloid (Aβ)protein. Neural progenitor cells (NPCs), which have the ability of multipotency, self-renewal and repair,have been detected in the central nerve system (CNS) of adult rat recently. But effective function of these neural progenitor cells are not seen in the AD brain ,which mechanism is unclear.It is unclear if Aβ1-40protein is compromised by the signal pathway of c-Jun N-termial kinase associated with the neurotoxicity to the progenitor cells on the cortex of embryonic rats.OBJECTIVE: To investigate the mechanism of c-Jun N-terminal kinase signal transduction pathway of Aβ1-40 protein, which has neuronal toxicity to progenitor cells(CPC)on the cortex of embryonic rats . To detect the neuroprotective effects of c-Jun N-termial kinase inhibitor (SP600125) against Aβ1-40-induced neuronal toxicity to the cortical progenitor cells on the cortex of embryonic rats.DESIGN: A randomized and controlled trial with cells as objects.SETTING: Department of Neurology, First Hospital Affiliated to China Medical UniversityMATERIALS: This experiment was carried out at the Central Laboratory,China Medical University from May to October 2005. Embryos at age of 14 days from Wistar rats were used in this experiment.METHODS: Cortical progenitor cells harvested from Wistar embryonic rats were cultured in vitro, passaged and identified. Embryonic rat cortical progenitor cells of rats with good growth state were randomly divided into 4groups:Aβ1-40 group (10 nmol/L Aβ1-40 in each well);SP600125+Aβ1-40group (10 μmol/L SP600125 for 30 minutes and then with 10 nmol/L Aβ1-40 in each well); SP600125 group ( 10 μmol/L SP600125 in each well); Normal saline group (same volume of normal saline). The incubated durations were 0,2 hours, 4 hours, 6 hours, 12 hours, 24 hours respectively,8 wells for each time point. The cell survival rate was measured by MTF assay (The concentration of cortical progenitor cells on the cortex was 1×10s L-1 in each group), the apoptosis rate was detected by flow cytometer (The concentration of cortical progenitor cells on the cortex was 1 ×1010 L-1in each group) and the expression of c-Jun N-termial kinase and p-c-Jun N-termial kinase, c-Jun,p-c-Jun were measured by Western Blot(The concentration of cortical progenitor cells on the cortex was 1×1013 L-1 in each group). t test was adopted for the comparison of difference in measurement data.sion of c-Jun N-terminal kinase, p-c-Jun N-termial kinase ,c-Jun and p-c-Jun of embryonic rat CPC .ture time in Aβ group and SP600125 +Aβ group, decreased obviously at 4hours; cellular survival rate in Aβ1-40 group was lower obviously than that in the other 3 groups at 0,2,4,6,12,24 hours (P < 0.01); Cellular survival rate in SP60025 +Aβ1-40 group was lower obviously than that in SP600125 group and normal saline group at 2,4,6,12,24 hours (P < 0.01);Compared with normal saline group, the difference of cell survival rate was not significant without time-dependent manner in SP600125 group (P> 0.05).amyloid protein group and SP600125 +Aβ group, increased obviously at 4hours; cell apoptosis rate in Aβ1-40 group was higher obviously than that of the other 3 groups at 0,2,4,6,12,24 hours(P < 0.01); Cellular apoptosis rate in SP60025+Aβ1-40 group was higher obviously than that in the SP600125 group and normal saline group at 2,4,6,12,24 hours (P < 0.01);Compared with normal saline group, the difference of cellular apoptosis rate was not significant without time-dependent manner in SP600125 group 12,24 hours without changes in Aβ1-40 group; the expression of p-c-Jun N-terminal kinase and p-c-Jun in Aβ1-40 group were seen at 0hour ,increased gradually, reached to the peak at hour 4 and decreased gradually.CONCLUSION: Aβ1-40 could inhibit the cell activity of CPC , reduce cellular survival rate and induce cellular apoptosis. c-Jun N-terminal kinase signal transduction pathway may mediate the Aβ1-40 inducd neurnal apoptosis in AD which may be one reason for unseen rescue mechanism in AD. SP600125 (c-Jun N-terminal kinase inhibitor) could inhibit the activation of c-Jun N-terminal kinase and c-Jun and protect the embryonic rats CPC from the Aβ1-40-induced neurotoxicity.