1.Study on preparation of the pH sensitive hydroxyethyl chitin/poly (acrylic acid) hydrogel and its drug release property.
Yu ZHAO ; Guohua CHEN ; Mingkun SUN ; Zhitao JIN ; Congjie GAO
Journal of Biomedical Engineering 2006;23(2):338-341
Hydroxyethyl chitin (HECH) is a water soluble chitin derivative made by etherification of chitin, ethylene chlorohydrin was used as etherification reagent in this reaction. A novel interpenetrating polymer network (IPN) composed of HECH/PAA was prepared. The IR spectra confirmed that HECH/PAA was formed through chemical bond interaction. The sensitivity of this hydrogel to temperature and pH was studied. The swelling ratio of this hydrogel in artificial intestinal juice is much greater than that in artificial gastric juice. The IPN hydrogel exhibited a typical pH-sensitivity, and its degree of swelling ratio increased with the increase of temperature. The sustained-release drug system of Dichlofenac potassium was prepared by using HECH/PAA as the drug carrier. The release experiment showed a perfect release behavior in artificial intestinal juice. This IPN is expected to be used as a good drug delivery system of enteric medicine.
Acrylates
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administration & dosage
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chemistry
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Anti-Inflammatory Agents, Non-Steroidal
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administration & dosage
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Chitin
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administration & dosage
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analogs & derivatives
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chemistry
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Delayed-Action Preparations
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Diclofenac
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administration & dosage
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Drug Carriers
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chemical synthesis
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Drug Delivery Systems
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Hydrogel, Polyethylene Glycol Dimethacrylate
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administration & dosage
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chemistry
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Hydrogen-Ion Concentration
2.Applications of extracorporeal membrane oxygenation and continuous renal replacement therapy for maintaining organs of potential organ donors with cardiopulmonary failure after brain death
Mingkun ZHAO ; Chuanshen XU ; Feng WANG ; Yunjin ZANG
Chinese Journal of Organ Transplantation 2019;40(5):293-297
Objective To explore the functions of extracorporeal membrane oxygenation (ECMO ) with continuous renal replacement therapy (CRRT ) for potential organ donors with cardiopulmonary failure after brain death and boost the coefficient of utilization of livers .Methods Analysis was conducted for clinical data of 5 donors with cardiopulmonary failure after brain death and their corresponding recipients from July 2015 to May 2017 .Five donors received the treatments of ECMO and CRRT .The relevant data included changes of blood pressure ,dosage of vasoactive agents , liver function ,renal function and urine volume of those treated donors .Also liver functions of liver recipients were observed .Then the clinical data of 18 normal DBD and their liver recipients were compared .Results After ECMO/CRRT ,donor blood pressures rose and the doses of vasoactive agents decreased .Meanwhile urine volume also increased .Finally 4/5 livers could be transplanted . And 10 kidneys were transplanted successfully .There was no significant inter-group difference of liver function .Conclusions The applications of ECMO and CRRT improve liver function of donors with cardiopulmonary failure after brain death and boost the rates of organ donation and utilization .
3.Factors influencing success of external cephalic version: analysis of 118 cases
Genxia LI ; Panpan ZHAO ; Chunhua CHENG ; Mingkun XIE ; Xianrong MENG ; Qinghua XU ; Jiao LI
Chinese Journal of Perinatal Medicine 2024;27(3):220-225
Objective:To investigate the factors influencing the success of external cephalic version.Methods:Pregnant women who underwent an external cephalic version due to breech or transverse presentation by the same operator in the Third Affiliated Hospital of Zhengzhou University from July 2015 to July 2021 were selected as the study objects. Univariate analysis and logistic regression analysis were used to explore the clinical factors influencing the success of the external cephalic version. The receiver operating characteristic (ROC) curve was used to analyze the best cut-off value of gestational week and amniotic fluid index at the time of operation and to evaluate the predictive value of the influencing factors on the success of the external cephalic version.Results:(1) A total of 118 cases finally entered this study. Among the 118 cases,77 cases (65.3%) succeeded in the external cephalic version, among which the success rate was 49.1% (27/55) for primipara and 79.4% (50/63) for multipara. The vaginal delivery rate was 56.8% (67/118). (2) Complications occurred in 19 (16.1%) of the 118 cases. The main complications were abnormal fetal heart rate (13 cases, 11.0%), umbilical cord presentation, and fetal position reversion (two cases and 1.7% in each), and the serious complications were intrauterine fetal death and placental abruption (one case and 0.8% in each).The complication rate of patients with successful external cephalic version was 7.8% (6/77), which was lower than that of those who failed the external cephalic version [31.7%(13/41)] ( χ 2=11.33, P=0.001). (3) Multivariate analysis showed that gestational week at surgery before 38, amniotic fluid index >11.10 cm, and multipara were the factors affecting the success of the external cephalic version [ OR(95% CI)=0.561(0.351-0.897), 1.173(1.018-1.351) and 4.201(1.547-11.404), all P<0.05]. (4) The area under the ROC curve of the combination of the gestational week at surgery, amniotic fluid index, and parity was 0.744 (95% CI: 0.640-0.848, P<0.001), and the Youden index was 0.518, with a sensitivity of 70.0% and a specificity of 81.8%. Conclusion:Gestational weeks, amniotic fluid index, and multipara are related to the success of the external cephalic version, and the combination of the three has certain predictive power for the success of the surgery.