Gut functions, such as gastrointestinal motility, gastric secretion and pancreatic secretion, were reduced with age. Glucose tolerance is impaired, and the release of insulin and beta-cell's sensitivity on glucose are reduced with age. However, a lot of controversial data have been reported as insulin concentrations after glucose ingestion are either higher or no different in elderly and young subjects. Thus, this study was aimed to investigate whether aging could affect pancreatic exocrine secretion and its action mechanisms. An isolated perfused rat pancreatic model was used to exclude the effects of external nerves or hormones. Pancreatic secretion was increased by CCK under 5.6 mM glucose background in the isolated perfused pancreas of young (3 months), 12 months and 18 months aged rats. There was no significant difference between young and aged rats. In 3 months old rats, CCK-stimulated pancreatic secretion was potentiated under 18 mM glucose background. However, the potentiation effects of endogenous insulin and CCK were not observed in 12 and 18 months old rats. Exogenous insulin also potentiated CCK-stimulated pancreatic secretion in 3 months old rats. Similarly, exogenous insulin failed to potentiate CCK-stimulated pancreatic secretion as that of 3 months old rats. Wet weight of pancreas and amylase content in pancreatic tissue were not changed with age. These results indicate that pancreatic exocrine secretion is reduced with age and endogenous insulin secretion and/or action is involved in this phenomenon.
Aged ; Aging ; Amylases ; Animals ; Cholecystokinin ; Eating ; Gastrointestinal Motility ; Glucose ; Humans ; Insulin ; Pancreas ; Rats

In the past decades, great progress has been made in cartilage regeneration. The traditional techniques for constructing tissue engineering cartilage scaffold mainly include pore agent method (or template method ) , phase separation method, gas foaming method, freeze-drying method , electrospinning method, etc. Cartilage is heterogeneous, and it is difficult for traditional scaffolds to simulate the high anisotropy of cartilage. Therefore, functional regeneration of cartilage is challenging. With the progress of three-dimensional (3D) printing technology, it is possible to prepare functional bionic scaffolds with fine structure and gradient changes through co deposition of biomaterials, cells and active biomolecules, so as to achieve functional cartilage regeneration. This article reviews 3D printing technology of cartilage tissue engineering, and the application of 3D printing technology in cartilage regeneration at different anatomical positions (articular cartilage, auricle cartilage, nasal cartilage) . In addition, the importance of preparing bionic constructs with regional structure gradient and regional composition gradient was discussed. 3D bioprinting technology, 4 D printing techniques, smart biomaterials brought hope for the construction of bionic tissues and organs.

In the past decades, significant progress has been achived in cartilage regeneration. The traditional techniques for constructing tissue engineering cartilage scaffold mainly include pore agent method (or template method), phase separation method, gas foaming method, freeze-drying method, electrospinning method, etc. Cartilage is heterogeneous, and it is difficult for traditional scaffolds to simulate the high anisotropy of cartilage. Therefore, functional regeneration of cartilage is challenging. With the progress of three-dimensional(3D) printing technology, it is possible to prepare functional bionic scaffolds with fine structure and gradient changes through co-deposition of biomaterials, cells and active biomolecules, so as to achieve functional cartilage regeneration. This article reviewed 3D printing technology of cartilage tissue engineering, and the application of 3D printing technology in cartilage regeneration at different anatomical positions (articular cartilage, auricle cartilage, nasal cartilage). In addition, the importance of preparing bionic constructs with regional structure gradient and regional composition gradient was discussed. 3D bioprinting technology, 4D printing techniques, smart biomaterials brought hope for the construction of bionic tissues and organs.

Objective To establish a real-time fluorescent recombinase polymerase amplification(RPA)technology for the detection of the virulence gene exoS of Pseudomonas aeruginosa,and evaluate the specifici-ty,sensitivity and practicability of the method.Methods According to the specific conserved region of the vir-ulence gene exoS of Pseudomonas aeruginosa,the specific primers and probes of RPA were designed,and the extracted target DNA was detected to determine the specificity and sensitivity of RPA.Real-time fluorescence quantitative PCR(qPCR)was established to detect the target DNA,and the detection limits of different detec-tion methods for Pseudomonas aeruginosa were compared.The feasibility of RPA in detecting Pseudomonas aeruginosa was further confirmed by the performance verification test of clinical samples.Results The estab-lished RPA detection method had good specificity.Only Pseudomonas aeruginosa had specific amplification curve,but no specific amplification curve for other bacteria.The sensitivity of RPA was 5×102 cfu/mL,which was consistent with the detection limit of qPCR and the results were reliable.The detection time of RPA method was only 30 min,which was significantly lower than that of the traditional method.Conclusion The RPA method for the detection of Pseudomonas aeruginosa established in this study has high specificity and sensitivity,and significantly shortens the detection time compared with the traditional detection method.It can be used for the rapid detection of Pseudomonas aeruginosa in clinical specimens.

In the past decades, great progress has been made in cartilage regeneration. The traditional techniques for constructing tissue engineering cartilage scaffold mainly include pore agent method (or template method ) , phase separation method, gas foaming method, freeze-drying method , electrospinning method, etc. Cartilage is heterogeneous, and it is difficult for traditional scaffolds to simulate the high anisotropy of cartilage. Therefore, functional regeneration of cartilage is challenging. With the progress of three-dimensional (3D) printing technology, it is possible to prepare functional bionic scaffolds with fine structure and gradient changes through co deposition of biomaterials, cells and active biomolecules, so as to achieve functional cartilage regeneration. This article reviews 3D printing technology of cartilage tissue engineering, and the application of 3D printing technology in cartilage regeneration at different anatomical positions (articular cartilage, auricle cartilage, nasal cartilage) . In addition, the importance of preparing bionic constructs with regional structure gradient and regional composition gradient was discussed. 3D bioprinting technology, 4 D printing techniques, smart biomaterials brought hope for the construction of bionic tissues and organs.

In the past decades, significant progress has been achived in cartilage regeneration. The traditional techniques for constructing tissue engineering cartilage scaffold mainly include pore agent method (or template method), phase separation method, gas foaming method, freeze-drying method, electrospinning method, etc. Cartilage is heterogeneous, and it is difficult for traditional scaffolds to simulate the high anisotropy of cartilage. Therefore, functional regeneration of cartilage is challenging. With the progress of three-dimensional(3D) printing technology, it is possible to prepare functional bionic scaffolds with fine structure and gradient changes through co-deposition of biomaterials, cells and active biomolecules, so as to achieve functional cartilage regeneration. This article reviewed 3D printing technology of cartilage tissue engineering, and the application of 3D printing technology in cartilage regeneration at different anatomical positions (articular cartilage, auricle cartilage, nasal cartilage). In addition, the importance of preparing bionic constructs with regional structure gradient and regional composition gradient was discussed. 3D bioprinting technology, 4D printing techniques, smart biomaterials brought hope for the construction of bionic tissues and organs.