ABSTRACT
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.
ABSTRACT
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.
Subject(s)
Hydrogels , Cartilage , Bone and Bones , Tissue Engineering/methodsABSTRACT
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 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.
ABSTRACT
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.
ABSTRACT
Objective:To study the significance of QT dispersion(QTd) changes in electrocardiogram(ECG) after coronary artery bypass graft. Methods:Forty eight patients scheduled for elective coronary artery bypass graft were studied. The changes of QTd were monitored by 12 lead electrocardiogram system before surgery (as baseline values), at the end of surgery, and 1 4 d and 7 d after surgery.Results:The baseline values for QTd was (56.32?2.25) ms.QTd were significantly longer as compared to the baseline values ( P
ABSTRACT
The aim of this study is to invistigate the effects of heparinization and the reversal of heparin activity with protamine on platelet function during extracorporeal cardiopulmonary bypass. The venous blood of 10 healthy volunteers was collected in tubes containing 3 2% trisodium citrate or 25??/ml heparin. The expression of P selectin (a secretion marker of platelets) and activated fibrinogen receptor GP Ⅱb Ⅲa (an aggregation marker of platelets) on normal platelets in response to the treatment with heparin and protamine in vitro were examined using whole blood flow cytometry. The results showed that heparin (5～50?g/ml) could increase adenosine diphosphate (ADP) induced expression of P selectin and GPⅡb Ⅲa in a dose dependent manner ( P