1.Immunoisolation effect of xenografts of microencapsulated human chromaffin cells in rats
Jiheng CHEN ; Maoyuan YANG ; Jiyong LI
Chinese Journal of Anesthesiology 1994;0(04):-
Objective To investigate the immunoisolation effect of xenografts of microencapsulated human chromaffin cells (HCCs) .Methods HCCs were microencapsulated with APA microcapsules. Forty-eight SD rats were randomly divided into 3 groups ( n = 16 each) . HCCs (group I ) , empty APA microcapsules (group II ) and microencapsulated HCCs (group III ) were implanted into the anterior chamber of the eyes and the sole of the feet. Seven days after transplantation blood samples were collected for determination of serum IL-2, IgG and IgM concentration. The right eye-balls and left feet were obtained for microscopic examination. Results The serum IL-2, IgG and IgM concentrations were significantly lower in group II and group III than in group I ( P
2.Immunoisolated effect of xenografts of microencapsulated human chromaffin cells in rats
Jiheng CHEN ; Maoyuan YANG ; Jiyong LI ; Xianzhong LIN ; Haosheng BI
Chinese Journal of Tissue Engineering Research 2008;12(1):166-169
BACKGROUND: Based on previous technique prepared for encapsulating living cells with alginate-polysine- alginate (APA) microcapsules, it has been confirmed that microencapsulated chromaffin cells have good analgesic effects. The immunoisolated effects of such microcapsule materials need to be evaluated. OBJECTIVE: This study aimed to investigate the immunological rejections of APA microencapsulated chromaffin cells transplanted into rat anterior chamber of eyes and tendon of feet, and to evaluate the immunoisolated effect of microencapsulation.DESIGN: A randomized controlled animal experiment. SETTING: Department of Anesthesiology, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology.MATERIALS: Forty-eight female SD rats, with the age of 3 months, were provided by the Laboratory Animal Center, Tongji Medical College, Huazhong University of Science and Technology. The protocol was carried out in accordance with ethical guidelines for the use and care of animals. Alginate and polylysine used in the experiment were the products of Sigma Company, USA. Microcapsule generator was gifted by Germany. METHODS: This study was performed at the Department of Anesthesiology, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology from September 2002 to September 2003. Suprarenal medulla was taken from 6 healthy adult cadavers of brain death. After isolated, digested and cultured, suprarenal medulla was prepared into chromaffin cell suspension. Written informed consents were obtained from the family members of donors, and the protocol was given approval by the Ethics Committee of the hospital. Empty microcapsules and microencapsulated cells were prepared by APA. The 48 rats were randomly divided into the human chromaffin cell (HCC) group, the empty microcapsule group and the microencapsulated HCC (ME-HCC) group. In each group, there were two transplanted regions of anterior chamber of eyes and tendon of feet, with 8 rats used for each region. Each rat in the HCC group was perfused 2×1010 L-1 cell suspension into the anterior chamber of eyes and tendon of feet. Those in the empty microcapsule group and the ME-HCC group were perfused 100 empty capsules and ME-HCCs (100 microcapsules, 400-500 HCCs per microcapsule) into the same regions, respectively. MAIN OUTCOME MEASURES: On day 7 after transplantation, serum interleukin (IL)-2 level was determined by ELISA. Serum IgG and IgM levels were determined with a laser turbidimeter. On day 28 after transplantation, rat right eyeball and left feet were harvested, routinely sliced and stained by haematoxylin-eosin (HE). Histo-morphological structure was observed under a 40×light microscope. RESULTS: Forty-eight rats were included in the final analysis. Serum IL-2, IgG and IgM levels were significantly lower in the empty microcapsule group and ME-HCC group than in the HCC group (t=8.544-21.64, P < 0.01). A lot of lymphocyte and neutrophile infiltration could be found in the anterior chamber of eyes and tendon of feet of rats in the HCC group, but a little seen in that of the empty microcapsule group and ME-HCC group. CONCLUSION: APA microencapsulation has an effective immunoisolated effect on immunological rejection due to its good biocompatibility and mechanical stability.
3.Clinical characteristics and antimicrobial resistance of Burkholderia cepa-cia causing infection in intensive care unit patients
Ling NAN ; Ding LIU ; Hao WANG ; Ping CHEN ; Maoyuan LI ; Qingning HUANG ; Qingyong FANG ; Yao CHENG
Chinese Journal of Infection Control 2015;(11):772-775
Objective To understand the specimen sources,clinical characteristics,and antimicrobial resistance of Burkholderia cepacia (B .cepacia )isolated from infected patients in intensive care unit(ICU),so as to provide reference for guiding rational use of antimicrobial agents.Methods Clinical data of patients with B .cepacia infec-tion in an ICU between 2011 and 2014 were analyzed retrospectively,antimicrobial resistance of strains was ana-lyzed.Results A total of 267 B .cepacia strains were isolated,the major specimen sources were sputum (80.15%, n=214),blood(14.23%,n =38),and urine(3.37%,n =9).Antimicrobial susceptibility testing results revealed that B .cepacia had multiple resistance,and was naturally resistant to multiple clinically used antimicrobial agents, such as ampicillin,cefazolin,ampicillin/sulbactam,nitrofurantoin,and cefuroxime,resistant rates were all 100%;resistant rates to ceftazidime and levofloxacin were 4.12% and 3.00% respectively;resistant rate to compound sulfa-methoxazole had increased tendency(χ2 =5.885,P =0.015).Conclusion Isolation of B .cepacia in ICU increased year by year,antimicrobial resistance is serious,management and targeted monitoring of prevention and control of healthcare-associated infection should be strengthened,antimicrobial agents should be chosen according to antimi-crobial susceptibility testing results.
4.Colonization and antimicrobial resistance of pathogens in nasal vestibular of health care workers in intensive care unit
Ling NAN ; Ding LIU ; Maoyuan LI ; Qingyong FANG ; Hao WANG ; Ping CHEN ; Qingning HUANG ; Yao CHENG
Chinese Journal of Infection Control 2016;15(8):608-611
Objective To understand colonization of pathogens in nasal vestibular of health care workers (HCWs) in intensive care unit (ICU),and provide evidence for strengthening the prevention and control of healthcare-associated infection (HAI)in ICU.Methods On may 2015,colonization status of pathogens in nasal vestibular of uninfected HCWs in ICU were actively screened,bacterial culture,isolation and identification were performed.The surveyed results were analyzed and compared with antimicrobial resistance of pathogens from patients at the same stage.Results A total of 96 HCWs were surveyed,43 pathogenic strains were isolated from different HCWs’na-sal vestibular,isolation rate and carriage rate were both 44.79%.The main pathogenic bacteria was Staphylococcus aureus(n=15,34.88%),followed by Enterobacter aerogenes (n =9,20.93%)and Klebsiella pneumoniae (K . pneumoniae ,n=7,16.28%).There was a high detection rate of pathogens from nasal vestibular of doctors,HCWs who smoked frequently and those who never exercised (all P <0.05).There were 1 strain of imipenem-resistant K . pneumoniae among 43 pathogenic strains.Resistance rate of 7 K .pneumoniae from HCWs to ampicillin/sulbactam, cefazolin,and furantoin were all >50.00%,resistance rates to cefotaxime and imipenem were 28.57% and 14.29%respectively;resistance rates of 11 strains of K .pneumoniae from patients to furantoin was 100.00% during the same stage,but were sensitive to other commonly used antimicrobial agents.Resistance rate of 4 strains of Esche-richia coli (E.coli)to ampicillin was 75.00%,to gentamicin,tobramycin,levofloxacin,ciprofloxacin,and com-pound sulfamethoxazole were all 50.00%,6 strains of E.coli isolated from patients during the same period were found to be resistant to most commonly used antimicrobial agents.Conclusion Colonization rate of pathogens is high in nasal vestibular of HCWs in ICU,active screening and monitoring on colonization of pathogens in HCWs’ nasal vestibular is significant for preventing the occurrence and cross transmission of HAI among HCWs and pa-tients.
5.Surgery treatment of hypertensive intracerebral hemorrhage in basal ganglia under direct vision by small bone window craniotomy approach assisted by the deep cold light suction
Zhi LIU ; Jun HE ; Qifu REN ; Fangping LI ; Huxiang LAN ; Maoyuan TANG ; Minruo CHEN
China Modern Doctor 2015;(11):48-51
Objective To discuss the clinical results and surgical method in treatment of hypertensive intracerebral hemorrhage in basal ganglia. Methods From January 2007 to June 2013, the use of surgery treatment of hypertensive intracerebral hemorrhage in basal ganglia under direct vision assisted by the deep cold light suction in 104 cases,all the cases were done through lateral fissure-brain island approach,removing the hematoma with bipolar coagulation and hemostasis at sametime. This paper analyzed the group of patients with surgical methods and clinical efficacy. Results CT scan of intreatment group showed that there were 6 cases of secondary operation because of recurrent hemorrhage, and the hematoma-cleared rate>80% in 73 cases,50%-80% in 21 cases,<50% in 10 cases before operation within 6 hours. According to ADL classification,the 92 cases were alive after operation, good recovery in 65 cases, moderate disability in 22 cases, 5 cases of severe disability, death and give up treatment 12 cases. There was 12 cases of sec-ondary operation because of recurrent hemorrhage in control group, and the hematoma-cleared rate>80% in 16 cases,50%-80%in 23 cases,<50%in 24 cases before operation within 6 hours. According to ADL classification,the 45 cases were alive after operation in control group, good recovery in 14 cases,moderate disability in 16 cases,15 cases of se-vere disability,death and give up treatment 18 cases. There were significant differences between the two groups in op-eration time, intra-operative blood loss, the volume of blood transfusion, hematoma clearance rate, postoperative sur-vival rate and the survival quality ADL grading at half a year, and the indexes mentioned above in treatment group were better than those in control group. Conclusion Surgery treatment of hypertensive intracerebral hemorrhage in basal ganglia under direct vision by lateral fissure-brain island approach assisted by the deep cold light suction will shooter the operation time and lower the surgical injury,increase hematoma-cleared rate,it aslo has reliable hemostasis and more effective,so this method is worthy of clinical use.
6.Effect of flash glucose monitoring on ambulatory glucose profile in patients with type 2 diabetes mellitus
Maoyuan CHEN ; Xiaofei SU ; Huiqin LI ; Yun SHEN ; Bingli LIU ; Rengna YAN ; Xiaojuan SUN ; Ling CAI ; Jianhua MA
Chinese Journal of Postgraduates of Medicine 2019;42(3):244-247
Objective To investigate the effect of flash glucose monitoring (FGM) on ambulatory glucose profile of only oral antidiabetic drugs treated patients with type 2 diabetes mellitus. Methods Twenty-eight type 2 diabetic mellitus patients with only oral antidiabetic drugs treatment from August 2017 to January 2018 were enrolled. All the patients were exposed to FGM for 14 d without changing the original treatment and encouraged to manage self-behavior by adjusting diet and activity based on the blood glucose data obtained from the real-time scanning. The changes in glucose profile during the FGM period were observed, including estimated glycated hemoglobin (HbA1c), standard deviation of blood glucose, variable coefficient of blood glucose, mean amplitude of glycemic excursions, time in range (blood glucose 3.9 to 10.0 mmol/L), area under the curve hyperglycemia (blood glucose> 10.0 mmol/L) and area under the curve hypoglycemia (blood glucose<3.9 mmol/L). The blood glucose levels on second day and thirteenth day were used as baseline and end point respectively. Results All of the 28 patients did not change their anti-diabetic drug therapy and there were no adverse events occurred. The estimated HbA1c was significantly lower than the baseline HbA1c: (6.90 ± 1.48)% vs. (7.57 ± 1.35)%, and there was statistical difference (P = 0.004). The standard deviation of blood glucose, variable coefficient of blood glucose, mean amplitude of glycemic excursions, area under the curve hyperglycemia and area under the curve hypoglycemia at end were significantly lower than those at baseline: (2.07 ± 0.86) mmol/L vs. (2.44 ± 0.86) mmol/L, 0.26 ± 0.11 vs. 0.30 ± 0.11, (5.32 ± 2.75) mmol/L vs. (6.76 ± 3.06) mmol/L, 265 (0, 1 310) vs. 351 (107, 2 177) and 0 (0, 0) vs. 0 (0, 19), the time in range at end was significantly higher than that at baseline: (1 069 ± 386) min vs. (921 ± 449) min, and there were statistical differences (P<0.05 or<0.01). The rate of scanning was (12.92 ± 4.87) times/d. Conclusions FGM could be applied by type 2 diabetic mellitus patients to make self-glycemic management without changing therapy, reduce the estimated HbA1c,and hypoglycemia, and improve the glucose fluctuations, which may result from real-time scanning to find abnormal glycemia and adjust daily behavior.
7.Preparation and application of injectable sodium alginate hydrogels
Xiaofang CHEN ; Guoshuang ZHENG ; Maoyuan LI ; Weiting YU
Chinese Journal of Tissue Engineering Research 2024;28(5):789-794
BACKGROUND:Sodium alginate,a natural polysaccharide,has become one of the ideal materials for preparing injectable hydrogels because it is an abundant and cheap resource,and has good biocompatibility and biodegradability.It has been widely used in the production of injectable hydrogels. OBJECTIVE:To review the properties of sodium alginate,the preparation of injectable sodium alginate hydrogel,and its application progress in tissue engineering. METHODS:Web of Science,PubMed,and CNKI were searched by computer.Chinese search terms were"sodium alginate;hydrogel;injectable",and English search terms were"alginate;hydrogel;inject".The time range of searching literature was mainly from June 2017 to June 2022. RESULTS AND CONCLUSION:Alginic acid comes from a wide range of sources,and there are many modifiable groups in its molecular structure,so many injectable hydrogels with excellent properties can be produced by various chemical crosslinking or physical crosslinking methods.Introducing other bioactive molecules or drugs into sodium alginate gel can adjust its properties and broaden its application fields.In addition,injectable sodium alginate hydrogels have great application prospects in biomedicine because of their good biocompatibility,biodegradability and other physical and chemical properties.Sodium alginate hydrogels are evenly mixed with various drugs,cells,factors or other biological molecules in vitro,and can form gels in the human body,which plays a pivotal role in gene carrier,cell scaffold and wound repair.
8.Bone/cartilage immunomodulating hydrogels: construction strategies and applications.
Maoyuan LI ; Guoshuang ZHENG ; Jiahui YANG ; Xiaofang CHEN ; Jianfeng XU ; Dewei ZHAO
Chinese Journal of Reparative and Reconstructive Surgery 2023;37(11):1423-1430
OBJECTIVE:
To review the research progress in the construction strategy and application of bone/cartilage immunomodulating hydrogels.
METHODS:
The literature related to bone/cartilage immunomodulating hydrogels at home and abroad in recent years was reviewed and summarized from the immune response mechanism of different immune cells, the construction strategy of immunomodulating hydrogels, and their practical applications.
RESULTS:
According to the immune response mechanism of different immune cells, the biological materials with immunoregulatory effect is designed, which can regulate the immune response of the body and thus promote the regeneration of bone/cartilage tissue. Immunomodulating hydrogels have good biocompatibility, adjustability, and multifunctionality. By regulating the physical and chemical properties of hydrogel and loading factors or cells, the immune system of the body can be purposively regulated, thus forming an immune microenvironment conducive to osteochondral regeneration.
CONCLUSION
Immunomodulating hydrogels can promote osteochondral repair by affecting the immunomodulation process of host organs or cells. It has shown a wide application prospect in the repair of osteochondral defects. However, more data support from basic and clinical experiments is needed for this material to further advance its clinical translation process.
Hydrogels
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Cartilage
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Bone and Bones
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Tissue Engineering/methods*