1.Preparation and performance of chitosan-gelatin sponge-like wound-healing dressing
Lanzhen HE ; Yi LIU ; Dan YANG
Chinese Journal of Tissue Engineering Research 2007;11(26):5252-5256
BACKGROUND:Chitosan has good filming and viscosity, it contains free amido, and can coordinate and cross-link with gelatin, thus natural semi-interpentrating polymer network structure can be formed among molecules through hydrogen bonds.OBJECTIVE: To prepare sponge-like wound-healing dressing of good porosity, hydrophilia and air permeability by means of frozen chitosan-gelatin mixture induced phase separation.DESIGN: A comparative observation.SETTING: Laboratory of the College of Science, Guangdong Ocean University. MATERIALS: Chitosan was deacetylated by 97.55%, Mη=1.85×106; Gelatin (CP grade) was produced by Shanghai Chemical Dispensing Factory; Glacial acetic acid, NaOH, formaldehyde and glycerin were all CP grade. XL30-EDAX scanning electron microscope (Philips, Dutch); 3365-type universal material testing machine. METHODS: ① By means of frozen chitosan-gelatin mixture induced phase separation chitosan solution of 0.2, 0.4, 0.5, 0.6 and 0.8 (mass fraction) was mixed with gelatin solution, then a small amount of glycerin to prepare sponge-like wound-healing dressing of good porosity, hydrophilia and air permeability. then a small amount of glycerin, and stayed quietly to deaerate. The samples were plated with gold as routine methods, and then the surface and sectional structures were observed under the scanning electron microscope. The effects of different proportion of chitosan and gelatin on the performance parameters (water retention, moisture absorption, avulsion intensity, air permeability rate) of the sponge-like materials were observed. ② Chitosan-gelatin mixtures of 18, 20, 22, 25, 24, 26 and 28 g/L (mass fraction) were used to prepare sponge-like materials, and the effects of different contents on the performances of the materials were observed. ③ The effects of cross-linking agent (formaldehyde) of different dosages (0.002, 0.004, 0.006, 0.008, 0.010, 0.012 and 0.014 in volume fraction) on the avulsion intensity of the materials were observed.MAIN OUTCOME MEASURES: ① Surface and sectional structures of the sponge-like wound-healing dressing; ② Effects of different proportion of chitosan and gelatin on the performance parameters of the sponge-like materials; ③ Effects of different contents on the performances of the chitosan-gelatin sponge-like materials; ④ Effects of cross-linking agent of different dosages on the avulsion intensity of the materials.RESULTS: ① It could be clearly seen from the surface that the chitosan-gelatin sponge-like materials were porous structure, whereas seen from the section, the pores were honey-comb formation or three-dimensional lamellar structure accumulated by porous lamellars. ② When the content of chitosan was greater, the section looked like honey comb;Whereas as the content of chitosan decreased and gelatin content increased, the section tended to parallel lamellar structure, the water content and water retention of corresponding samples had an ascending trend, but the alvusion iintensity increased at first, and then decreased. The mass fraction of 0.5 was suitable for chitosan in the prepared solution by comprehensively analyzing the performance parameters. ③ The lower the total concentration of chitosan and gelatin, the higher the water content, the easier for the formation of bigger self-chips on the surface, the porosity of the prepared materials increased, hydrophilia and water retention ability were increased, but greater cracks formed on the material surface, and avulsion intensity was smaller. As the concentration became higher, the viscosity of the mixture became greater, the excessive viscosity was not good for mixing uniform, thus the material surface was not plain enough, and the porosity was smaller, the hydrophilia and water retention ability were relatively decreased, and the materials were harder. The total concentration should be 22-25 g/L. ④ Once the dosage of cross-linking agent was too low, very few cross-linking points generated, and the intensity was too low; Once the dosage of cross-linking agent was too high, too many cross-linking points generated, and the net space was reduced, then water content and water retention value were decreased; Whereas overdosage cross-linking agent could increase the fragility of the sponge-like materials, manifested as the decrease of avulsion intensity. When formaldehyde of 0.01 in volume fraction, the avulsion intensity was the maximal, thus the dosage of 0.01 in volume fraction was the most suitable.CONCLUSION: The main factors that affect the structures and performances of the sponge-like wound-healing dressing are the proportion of chitosan and gelatin in the mixture, total concentration of the prepared solution, amount of powder and dosage of cross-linkage agent, etc. The best matching iss chitosan of 0.05 (volume fraction)/gelatin of 0.05 (volume fraction), total mass concentration of 22-25 g/L, amount of chitosan-gelatin powder mixture is 1∶1, and the dosage of cross-linking agent is 0.01 (volume fraction).
2.Survey on the current situation of patients xeroxing medical records
Yi HE ; Yongyou LIU ; Wenqing ZHOU
Chinese Journal of Hospital Administration 1996;0(07):-
Objective To understand the current situation and motives of patients xeroxing medical records and the various factors affecting patients' right to know. Methods A cross-sectional survey was made on people who xeroxed medical records with self-made questionnaires and methods of descriptive analysis and stepwise regression analysis were then used to analyze 306 returned questionnaires. Results 98.37% of those surveyed showed approval for the procedures regarding the xeroxing of medical records; 98.04% felt satisfied with the hospital's medical records control; and the chief motives of patients xeroxing medical records were data keeping (28.57%) and medical insurance(27.12%). The current state of knowledge possessed by people xeroxing medical records about patients' rights was unsatisfying. Conclusion Patients' awareness of their right to xerox medical records and their satisfaction towards the hospital's medical records control are fairly high, and yet efforts still need to be made to step up propaganda among rural and elderly people.
3.Two cases of epiglottic neuroendocrine carcinoma.
Hui LIU ; Yi ZHAO ; Xiaoguang HE
Journal of Clinical Otorhinolaryngology Head and Neck Surgery 2014;28(19):1531-1532
Neuroendocrine tumors of the epiglottis were extremely rare. Patients normally had no obvious symptoms and signs of early stage. Epiglottis lingual except (without) tubercle of epiglottis, and hyperplastic mass were observed by using laryngoscopy and also confirmed by biopsy and immunohistochemistry. Immunohis- tochemical studies showed that Syn, a broad spectrum endocrine marker, and CgA, a specific marker of endocrine tumor, were both positive. Which is consistent with the diagnosis of neuroendocrine carcinoma.
Carcinoma, Neuroendocrine
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pathology
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Epiglottis
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pathology
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Humans
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Immunohistochemistry
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Laryngeal Neoplasms
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pathology
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Laryngoscopy
4.NF-κB inhibitor reduces the expression of zincfinger protein A20 in rabbit lumbar intervertebral disc nucleus pulposuscells induced by lipopolysaccharide
Yafeng WEN ; Weiwei YI ; Xi LIU ; He YE ; Bo LIU
Basic & Clinical Medicine 2017;37(5):601-607
Objective To observe the expression of zinc finger protein A20(A20), NF-κB and related inflammatory factors before and after lipopolysaccharide (LPS) stimulates degeneration of rabbit intervertebral disc nucleus pulposus cells.Methods The normal and degenerative nucleus pulposus cells were isolated and cultured, then divided into normal group,degenerative group,LPS stimulation group and NF-κB inhibition group.HE staining observe the morphological changes of nucleus pulposus and annulus fibrosus,immunohistochemistry was used to detect the expression of A20,NF-κB/p65 and COL-Ⅱ.Real-time PCR was employed to analyze the expression of A20,IL-1β,TNF-α,NF-κB and COL-Ⅱ,Western blot was used to observe the A20 protein,p65 and COL-Ⅱexpression in the four groups, and TNF-α, IL-1β in cell supernatant was determined by ELISA.Results The number of nucleuspulposus cells significantly decreased, aggregation occured in the degenerative group.COL-Ⅱ was obvious lower and A20, p65 significantly higher than that in normal group by immunohistochemical staining.Compared with the normal group,A20,TNF-α,IL-1β,p65 expression was significantly increased and COL-Ⅱ decreased in the mRNA and protein levels in degenerative group.Above indexes changed more significant in LPS stimulation group than in degenerative group.The expression of A20, TNF-α, IL-1β, p65 in the NF-κB inhibitor group was lower than that in the LPS group, and the expression of type Ⅱ collagen increased(P<0.05).Conclusions Intervertebral disc inflammatory response is closely related to the development of intervertebral disc degeneration, A20 may play an important role.
6.The gene expression anti role of Wnt signal pathway in liver fibrosis
Wujun XIONG ; Yi HE ; Fei LIU ; Ming JIANG ; Yanbing LIU
Chinese Journal of Digestion 2008;28(9):612-616
Objective To study the gene expression of Wnt signal transduction pathway in experimental liver fibrosis and to investigate its role in liver fibrosis. Methods Liver fibrosis model was induced with carbon tetrachloride in 8 SD rats. Another 8 healthy rats were served as control. The gene expression in liver tissues of models and controls were examined using real time PCR array. The differential gene expression was identified as either up- or down-regulated 2-fold. The expressions of smooth muscle actin (SMA), Wnt4, Frizzled2 and β-catenin in the tissues were examined by immunohistochemistry and Western blot. Results The examination confirmed that 36 genes were differentially expressed, including 25 genes up-regulated and 11 genes down-regulated. Compared with the controls, the expressions of Wnt4, Wnt5 a and W nt11 were up-regulated more than 13.9-, 16.5-and 2.17-fold respectively, while the expressions of Wntl and Wnt3 were down-regulated more than 2.32- and 2.15-fold respectively in fibrotic liver. Immunohistochemistry and Western blot showed that the expressions of SMA, Wnt4 and Frizzled2 in fibrotic liver were remarkably higher than those in normal controls. While the level of phosphorylated β-catenin was decreased. Conclusion Both canonical and noncanonical Wnt signal transduction pathway may involve in the mechanism of liver fibrogenesis.
7.Design, synthesis and antiepileptic activity of 4-(2-acetoxybenzoylamino) butyrate derivatives.
Wenhu LIU ; Dian HE ; Xinqiang YIN ; Yi LIU
Acta Pharmaceutica Sinica 2011;46(3):299-304
A series of 4-(2-acetoxybenzoylamino) butyrate derivatives were designed and synthesized. All of the novel 12 compounds (7a-7k) were synthesized from gamma-aminobutyric acid (1) as starting material, and their structures were confirmed with IR, 1H NMR, EI-MS and elemental analysis. Preliminary pharmacological test in vitro showed that most of these title compounds possessed antiepileptic activity. Compounds 7i-7k displayed strong antiepileptic activity and are worth for further development. Compounds 4, 7d-7h showed moderate antiepileptic activity. The structure-activity relationship of 4-(2-acetoxybenzoylamino) butyrate derivatives is also discussed preliminarily.
8.Prostate cancer: diagnostic value of quantitative analysis by dynamic contrast-enhanced MR at 3.0 T
Wei HE ; Yi LIU ; Jianyu LIU ; Min LU
Chinese Journal of Radiology 2014;48(3):215-218
Objective To investigate the diagnostic value of the quantitative analysis parameters of dynamic contrast-enhanced MRI (DCE-MRI) for prostate cancer.Methods MR examination were performed in 26 patients and correlations were made with surgical pathology following radical prostatectomy.According to the localization of pathologic specimens,ROI were drawn on areas of cancerous regions,noncancerous regions in peripheral zone and central gland to measure the values of Ktrans,kep and Ve.The values of the three parameters in different tissue were compared with Kruskal-Wallis H and Mann-Whitney U.Results Twenty six patients had prostate cancer confirmed by pathology.Data from 468 assessable regions of prostate were acquired,including 115 cancerous regions and 142 noncancerous regions in central gland,68 cancerous regions and 143 noncancerous regions in peripheral zone.Prostate cancer showed a multifocal distribution.The K,kep and Ve values were (1.04 ± 0.26)/min,(1.43 ± 0.46)/min,(0.76 ±0.12) respectively for cancerous regions in central gland,and (0.82 ±0.19)/min,(1.12 ±0.26)/min,(0.75 ± 0.14) respectively for noncancerous regions in central gland,(0.95 ±0.31)/min,(1.31 ±0.51)/min,(0.76 ± 0.13) respectively for cancerous regions in peripheral zone and (0.32 ± 0.07)/min,(0.52 ± 0.13)/min,(0.64 ± 0.14) respectively for noncancerous regions in peripheral zone.The differences among the three parameters were statistically significant (x2 =316.008,297.985,63.681,P <0.01).The Ktrans,kep values of cancerous regions were significantly higher than the corresponding values of noncancerous regions,respectively.Conclusion Quantitative analysis parameters of DCE-MRI contribute to the diagnosis of prostate cancer,including cancer located in central gland.
10.The mediating effect of personality between schizophrenia and prospective memory
Zhikai LIAN ; Zhanbiao SHI ; Yushan LIU ; Liu YANG ; He LI ; Yi LE ; Ling HE
Chinese Journal of Behavioral Medicine and Brain Science 2015;24(3):233-236
Objective To explore the differences between schizophrenic patients and normal at prospective memory,and investigate the effect of personality intermediary between schizophrenia and prospective memory.Methods A case-control study was utilized in this research.It used the color matching task to test prospective memory and MMPI-2 scale to test personality differences between the two groups.Results Schizophrenia prospective memory score(19.29±2.30),lower than the normal group(44.74±2.06),the difference was significant(P<0.01).In mediating effect on the personality inspection,the subscales within MMPI-2 of Social Scale(Si) and Anxiety and tension Scale(ANX) regression coefficients were tested(P<0.05),which showed significant effect.Further analysis with sobel statistics showed that only one factor tested was significant.The test coefficients of depression scale (D),mental weakness scale (Pt) and schizophrenia scale (Sc) were significantly different (P< 0.05),which showed that these subscales also had significant mediating effect.Conclusion The prospective memory performance is low in schizophrenia.The personality characteristics that depression,mental weakness,schizo phrenia,social anxiety and tension play an intermediary role in schizophrenia and prospective memory.