Surveillance on the adverse events following immunization in Dazu District of Chongqing， 2016‒2020 / 上海预防医学

ObjectiveTo determine the incidence and characteristics of adverse events following immunization （AEFI） in 2016‒2020 in Dazu District of Chongqing， and evaluate the AEFI surveillance information system and provide scientific evidence for vaccine safety. MethodsDescriptive epidemiological analysis was performed on the cases collected by the AEFI surveillance system. Incidence and coverage of AEFI were then presented. ResultsA total of 319 AEFI cases were reported in 2016‒2020. Reported incidence of AEFI was determined to be 24.64/105 doses. The proportion of timely reporting AEFI within 48 hours was 94.04% and that of timely investigation within 48 hours was 98.41%. The proportion of completing the AEFI survey was 100.00% and that of AEFI classification was 99.69%. The male to female ratio was 1.28∶1. Majority of the AEFI cases were less than 1 year old （64.26%， 205/319）， from April to September （68.97%， 220/319）， and reported at 0‒1 day post-immunization （89.34%， 285/319）. Moreover， the reported incidence differed significantly between time periods （χ2=32.481，P<0.05） and time intervals from vaccination to occurrence of AEFI （χ2=961.408， P<0.05）. Coverage of reporting AEFI at county level reached 100％. In addition， non-severe AEFI cases accounted for 98.43% （314/319） and no death case was reported. General events， such as fever， redness， and scleroma， accounted for 80.56% （257/319）， whereas rare adverse events accounted for 15.99% （51/319）. The reported incidence of NIP vaccines was highest in the diphtheria tetanus acellular pertussis combined vaccine， followed by measles and rubella combined attenuated vaccine and diphtheria tetanus combined vaccine. Clinical diagnosis of rare adverse events was mainly allergic rashes. ConclusionThe AEFI surveillance information system in Dazu District of Chongqing achieves efficient monitoring of AEFI. It has proven that the vaccines are generally safe and immunization strategies may be continuously implemented. Furthermore， the sensitivity of AEFI surveillance should be improved through multiple approaches.

Electrospun Fibrous Silk Fibroin/Poly(L-Lactic Acid) Scaffold for Cartilage Tissue Engineering

For successful tissue engineering of articular cartilage, a scaffold with mechanical properties that match those of natural cartilage as closely as possible is needed. In the present study, we prepared a fibrous silk fibroin (SF)/poly(L-lactic acid) (PLLA) scaffold via electrospinning and investigated the morphological, mechanical, and degradation properties of the scaffolds fabricated using different electrospinning conditions, including collection distance, working voltage, and the SF:PLLA mass ratio. In addition, in vitro cell-scaffold interactions were evaluated in terms of chondrocyte adhesion to the scaffolds as well as the cytotoxicity and cytocompatibility of the scaffolds. The optimum electrospinning conditions for generating a fibrous SF/PLLA scaffold with the best surface morphology (ordered alignment and suitable diameter) and tensile strength (~1.5 MPa) were a collection distance of 20 cm, a working voltage of 15 kV, and a SF:PLLA mass ratio of S50P50. The degradation rate of the SF/PLLA scaffolds was found to be determined by the SF:PLLA mass ratio, and it could be increased by reducing the PLLA proportion. Furthermore, chondrocytes spread well on the fibrous SF/PLLA scaffolds and secreted extracellular matrix, indicating good adhesion to the scaffold. The cytotoxicity of SF/PLLA scaffold extract to chondrocytes over 24 and 48 h in culture was low, indicating that the SF/PLLA scaffolds are biocompatible. Chondrocytes grew well on the SF/PLLA scaffold after 1, 3, 5, and 7 days of direct contact, indicating the good cytocompatibility of the scaffold. These results demonstrate that the fibrous SF/PLLA scaffold represents a promising composite material for use in cartilage tissue engineering.

Biocompatibility of a non-woven silk fibroin and poly L-lactic acid net and evaluation on its safety / 吉林大学学报(医学版)

Objective To study the biocompatibility of silk fibroin/poly L-lactic acid (SF/PLLA) non-woven network,a kind of new composite tissue engineering nanomaterials,and to explore its possibility as the biological implant materials.Methods The PLLA non-woven network was prepared by electrostatic spinning.Physiological saline as control,the leaching solution was prepared and injected into the mice,then the mice were observed for 2 weeks.The materials were implanted into the back of the mice,and 3-0 suture was used as control.Tissues were collected at 1,2,3,and 4 weeks after operation,dyed by HE staining and then the photos were taken.The tissue reactions in experimental group and control group were observed.The rabbit knee joint cartilage cells were cultured,and then subculture cells were seeded to the surface of materials.After cultured invitro,the adhesion and growth of the cells were observed with inverted optical microscope.The bioactivities of the rabbit knee joint cartilage cells in negative control group(DMEM culture media),experimental group(DMEM containing materials) and positive control group(DMEM containing phenol solution)were determined by MTT assay after cocultured for 24 and 48 h.Results After injection,the body status of the mice in experimental group was the same to the control group.There were little fibroblasts was and a little of lymphocytes and macrophage cells in the materials which were implanted into the back of the mice at the beginning.Then the number of the fibroblasts was increased, but the number of the lymphocytes and macrophage cells did not change obviously.The materials degraded slowly, and the material degraded obviously at 4 weeks.The inflammation of tissue around the material reduced gradually from the 2nd week.The inflammation of tissue around the material was the same to the suture,and sometimes was slighter than the suture.After sed for 24 h,there were cells attaching to the fibers of the material.More and more cells attached to the fibers.The reasult of MTT assay showed that the cytotoxicities in experimental groups were all on LevelⅠ at 24 and 48 h.Except for positive control group,the A values were increased in other groups with the extended response time.At the same time,there was no significant difference in cytotoxicity between experimental group and negative control group(P>0.05)and the A value in experimental group was higher than that in positive control group(P<0.01).Conclusion The SF/PLLA non-woven network scaffold material has good biological compatibility and safety,it could be used as implant material in tissue engineering.

Progress of caspase inhibitors in pharmacology / 中国临床药理学与治疗学

Apoptosis is involved in a variety of diseases. Cysteine aspartate specific protease (caspase), a protease family which executes apoptosis, plays a crucial role in course of apoptosis. It can be activated through various pathways. Some natural and synthetic caspase inhibitors will strengthen anti apoptotic action through inhibiting one or several caspase activity, and will become effective means in treating diseases caused by overapoptosis.