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).

Objective To investigate the effect of Toutongning capsule for treatment of headache with stroke-associated risk fac-tors .Methods 60 cases of headache patients with stroke-associated risk factors were selected and divided into the treatment group and the control group ,30 cases in each group .The treatment group were given conventional therapy plus Toutongning capsule while the control group were given conventional therapy only .Results After 4 weeks ,the remission rate of treatment group was 93% and that of the control group was 63% .The attack frequency ,duration and degree between the two groups showed statistically signifi-cant difference(P<0 .05) .Conclusion Additional Toutongning capsule has a better effect for treatment of headache with stroke-as-sociated risk factors.

OBJECTIVE: To study the expression of Cyclin D1 in nasopharyngeal carcinoma cells processed by epigallocatechin gallate(EGCG) and it's significance, and revealed the anti-tumor mechanism of EGCG against nasopharyngeal carcinoma. METHOD: CNE-2 cells were treated by EGCG at different concentrations, the morphological changes of CNE-2 cells were observed by inverted microscope; the inhibition ratio of cell proliferation was detected by MTT colorimetric method, flow cytometry was used to analyze the changes of cell cycle. The expression of Cyclin D1 mRNA was detected by RT-PCR. RESULT: After treated by EGCG, the CNE2 cells decreased in amount and density, some of which became roll and small; Floating and dead cells can be seen in the inverted microscopy; cell proliferation was significantly inhibited in a time and dose dependent (P < 0.05). CNE-2 cells were arrested at G1/G0 phase. The expression of Cyclin D1 mRNA was down-regulated by EGCG with concentration and action time dependent (P < 0.05). CONCLUSION EGCG resisted nasopharyngeal carcinoma by inhibiting the cell proliferation, The down regulation of Cyclin D1 mRNA expression in a time and dose dependent may be the possible mechanisms.
Carcinoma ; Catechin ; analogs & derivatives ; pharmacology ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cyclin D1 ; metabolism ; Humans ; Nasopharyngeal Carcinoma ; Nasopharyngeal Neoplasms ; metabolism ; pathology

AIM: To detect unknown CD44 variants(CD44v) in nasopharyngeal cancer by using reverse transcription-polymerase chain reaction(RT-PCR) to analyze the expression of cell adhesion protein CD44 gene in nasopharyngeal cancer tissue and cell lines.METHODS: Specific primers at up start code,down terminal code of CD44 and primers at the middle,splicing points of variable splicing exon v10 of CD44 were designed.cDNA of nasopharyngeal cancer tissues,5-8F and HNE1 cell lines were analyzed by RT-PCR.Products of RT-PCR were sequenced and further analyzed by bioinformatics.RESULTS: The new CD44v sequence possessed 1634 bp with a completed open reading frame.The start code was at 12 bp site and terminal code at 1301bp site.It was predicted to code 429 amino acids,and only variable splicing exon 10 existed in the flexible region.It was given an accessible number EF581837 by GenBank.CONCLUSION: A new CD44 variant predicted to code 429 amino acids exists in the studied nasopharyngeal cancer tissues and cell lines.

Objective To explore the clinical application of blood return by tee union among central venous catheter ( CVC) in hemodialysis patients. Methods A total of 90 MHD patients had been selected and randomly divided into group A (opening blood return), group B (closing blood return), and group C (blood return by tee union) on average from August 2013 to July 2014 in Hemodialysis Center. We documented the length of blood return, the volume of 0. 9% sodium chloride solution, red-cell count ( RCC) in the residual liquid after dialysis, the change of C reactive protein at the beginning of treatment, 6 months and 12 months after treatment, and the rate of CVC relative infection ( CVC-RI) among three groups. Results The length of blood return were (291.04 ±46.92),(340.75 ±51.36), (278.99 ±45.21)s in A, B, C group, the volume of 0. 9% sodium chloride solution (186. 72 ± 27. 65),(257. 24 ± 40. 07),(191. 11 ± 32. 53) ml, the number of RCC in the residual liquid after dialysis (4 628. 4 ± 501. 6),(5 104. 5 ± 592. 7), (4 588. 2 ± 546. 9)/μl (F=3. 932 7,4. 529 1,3. 133 8;P<0. 05). Compared each two of three groups, the differences of each indexes between group A and group C were no statistically significant (P>0. 05), but the length of blood return in these two groups were shorter than that of group B (P<0. 05). After 6 and 12 months, the level of CRP in group B and C was lower than that of group A (P<0. 05);the different time point of CRP, it presented that it increased with the length of treatment in the group A (P <0. 05), but these of group B and C had no statistical significance at three time point (P>0. 05). The incidence rate of CVC-RI were 40. 00%, 16. 67%, 13. 33%in group A, B and C (χ2 =7. 080 7,P<0. 05);these of group B and C was lower than that of group A ( P<0. 05), but the statistical significance did not exist between group B and C (P >0. 05). Conclusions The CVC in hemodialysis patients utilized tee union for blood return which is simple, organized, saving time and labor, and reduced the potential risk of CVC-RI, slight infection symptom and the volume of sodium chloride solution.