Objective:To investigate the influencing factors of asthma recurrence in preschool children.Methods:From January 2019 to December 2020, a total of 160 preschool children with asthma in the pediatric inpatient department of the Third People′s Hospital of Henan Province were included as the research subjects. After standardized treatment, the drug was discontinued and the patients were followed up for 1 year. A total of 6 cases were lost or withdrawn during the follow-up, and finally 154 cases were included and divided into recurrence group (91 cases) and non-recurrence group (63 cases) according to the presence or absence of recurrence. The data of these children were collected and recorded, and logistic regression analysis was used to explore the influencing factors of asthma recurrence in children, and to explore the corresponding intervention strategies.Results:The results of univariate analysis showed that the differences in guardian′s education level, asthma family history, asthma severity, coexisting allergic rhinitis, coexisting sinusitis, standardized medication course, combined medication, drug withdrawal season, adherence to regular follow-up visits, etc. were statistically significant between the two groups of asthmatic children (all P<0.05). Multivariate Logistic regression analysis showed that the children′s guardians had low educational level (junior high school and below) ( OR=1.960, 95% CI: 1.714-2.206), family history of asthma ( OR=2.277, 95% CI: 1.850-2.705), coexisting allergic rhinitis ( OR=2.034, 95% CI: 1.520-2.548), severe asthma ( OR=1.866, 95% CI: 1.026-2.707), drug withdrawal in spring or winter ( OR=1.861, 95% CI: 1.704-2.018) were risk factors for asthma recurrence, while standard medication duration >12 months ( OR=0.465, 95% CI: 0.304-0.712), combined medication ( OR=0.458, 95% CI: 0.297-0.705), adherence to regular follow-up visits ( OR=0.559, 95% CI: 0.389-0.803) were protective factors for asthma recurrence in children (all P<0.05). Conclusion:Family history of asthma, coexistence of allergic rhinitis, severity of asthma, adherence to regular follow-up visits, and standardized and combined medication are the main factors affecting asthma recurrence in preschool children, and clinical intervention strategies can be formulated accordingly.

Objective To apply 3D printing technology to fabricate patient-specific silicone tissue compensators for the chest wall and compare the advantages and clinical characteristics between conventional bolus and 3D-printed PLA materials. Methods The chest wall data of two breast cancer patients undergoing mastectomy were obtained based upon the CT images. A patient-specific 3D printing silicone rubber bolus (3D-SRB) was designed and fabricated. The conformability of 3D-SRB,3D-PLA and conventional bolus to the chest wall were validated. Ecipse8. 6 planning system was adopted to statistically compare the dosimetric parameters of virtual plan with those after using three tissue compensators. Results The 3D-SRB was successfully designed and fabricated with a similar hardness to conventional bolus. During the process of validating conformability and radiotherapy planning,3D-SRB and 3D-PLA were superior to conventional bolus in terms of conformability to chest wall and planning dosimetric distribution.3D-SRB was advantageous in repeatability, conformability and comfortable experience compared with 3D-PLA. Regarding dosimetric parameters,3D-SRB yielded the highest repeatability with the virtual plan, followed by 3D-PLA and conventional bolus. Conclusion It is applicable to utilize 3D-SRB as the patient-specific compensators for the chest wall,which is of significance in clinical practice.

Objective To construct the recombinant plasmid of protein CFP10-MPT48-TB8.4 of Mycobacterium tuberculosis and to investigate the diagnosis potential of this fusion protein in tuberculosis serodiagnosis.Methods The recombinant fusion protein CFP10-MPT48-TB8.4 was expressed, and identified by Western blot.The ELSIA based on the purified fusion protein was done,and used for screening in 230 cases of clinical serum samples including pulmonary tuberculosis patients ( n =150 ),pulmonary disease patients other than tuberculosis (n =70) and health controls (n =103 ).The test result was analyzed by Medcale11.5 software.Results The fusion protein CFP10-MPT48-TB8.4 was successfully expressed with a purity over 95％.Specific immunogenicity of the recombinant protein was confirmed by Western blot.The overall sensitivity and specificity obtained of ELISA were 56.7％ (85/150) and 90.8％ ( 157/173 ),respectively.The specificity was 85.7 ％ (60/70) in non-tuberculosis group and 94.2％ (97/103 ) in healthy group,respectively.Conclusion The recombinant protein of CFP10-MPT48-TB8.4 has a high sensitivity and specificity and may be a potential candidate antigen in tuberculosis serodiagnosis.

Objective To establish a stable in vitro model of blood-brain barrier (BBB) simulating in vivo state using the primary-cultured rat brain microvascular endothelial cells (BMVECs) and pericytes.Methods The primary rat BMVECs and pericytes were isolated,purified and cultured.The isolated cells were identified by immunocytochemical staining method.An in vitro model of BBB was constructed using Transwell inserts (pore size 0.4 μm) coculture.Its barrier function was evaluated by the 4-hour leakage test,tight junction protein identification,transendothelial resistance detection,and permeability test.The difference between the cocultured model and simple BMVEC model across the membrane resistance values,and the permeability difference of the small molecule sodium fluorescein (Na-F) were compared.Results Confluent BMVEC monolayers demonstrated a typical cobblestone appearance and the pericytes displayed irregular shape and overlapping growth.Immunodouble labeling technique identification showed that the pericytes positively expressed α-srmooth muscle actin (α-SMA) and neuron-glial antigen 2 (NG2); after the fusion of cocultured model endothelial cells,the surface leakage test became positive; immnocytochemical staining shows that a continuous and dense tight junction formed between the endothelial cells; compared to the BMVEC model,the transendothelial electrical resistance of the cocultured model increased significantly (190.762 ± 10.326 Ω/cm2 vs.96.503 ± 8.012 Ω/cm2; t=- 24.489,P ＜0.01),and the permeability decreased significantly (56.149％ ± 3.572％ of the single endothelial model; t =19.330,P ＜ 0.01 ).Conclusions The primary isolated rat BMVECs and pericytes cocultured the morphology,structure and barrier function of in vitro model have the basic characteristics of BBB,and they have provided a useful tool for the research of BBB.

Objective To explore the method of primary isolation, cultivation and identification of rat brain microvessel pericytes. Methods The brain tissue of 10 3 week-old Wistar rats was separated sterilely. The brain microvessel fragments were separated using two-step enzyme digestion and one-step gradient centrifugation and were seeded in 35-mm dishes for primary culture. The cell morphology was observed by phase contrast microscopy; the immunofluorescence assay was used to identify the associated antigns, such as the α-smooth muscle actin (α-SMA), neuron-glial antigen 2 (NG2), von Willebrand factor (vWF), and glial fibrillary acidic protein (GFAP). Methyl thiazolyl tetrazolium was used to determine the cell growth curve. Results Pericytes climbed out from the adherent brain microvascular fragments around,showing polygonal, and the cell fusion was 95％ after 12-14 days. Immunofluorescence staining revealed that the molecular markers of the pericytes α-SMA and NG2 related antigens showed double positive, while the vWF and GFAP related antigens showed double negative and the cultured cells were confirmed as brain microvascular pericytes. The growth rate of primary cells was slower. The passage cells entered into logarithmic growth phase after 36 to 60 hours and entered into plateau phase after 72 to 108 hours. Conclusions This method may successfully isolate rat brain microvascular pericytes with higher purity.

Objective To develop an assay to determine Mycobacterium tuberculosis resistance to rifampin, isoniazid, ofloxacin and amikacin by pyrosequencing and evaluate the value of this method in clinical application. Methods Eighty-nine clinical isolates of Mycobacterium tuberculosis from tuberculosis patients were collected from Shanghai Pulmonary Hospital during 2008 to 2009. All strains were isolated from decontaminated sputum, cultured on Lowenstein-Jensen media and identified by traditional biochemical tests with standard methods. Ten Mycobacterium tuberculosis were selected from the strain bank of Shanghai Pulmonary Hospital. The optimal conditions of detection of rpoB, katG, gyrA and rrs gene by pyroseuencing were determined, using the 10 Mycobacterium tuberculosis strains whose drug susceptibility of Bactec 960 and sequence of rpoB, katG, gyrA, rrs gene were known. Then the drug susceptibility of 89 Mycobacterium tuberculosis clinical isolate strains were detected by pyrosequencing using this conditions and the results were compared with that of the Bactec 960 methods. Results The pyrosequencing program of sequence analysis was suitable for the detection of the mutations of rpoB and gyrA genes, and the program of single nucleotide polymorphism was suitable for katG and rrs genes. Among the 89 Mycobacterium tuberculosis clinical isolates,when using the drug susceptibility of Bactec 960 as the standard, the sensitivity of rifampin, isoniazid,ofloxacin and amikacin is 98.0%, 64. 1%, 79.5%, 78. 3% respectively, the specificity is 97.5%,100. 0%, 90. 0%, 100. 0% respectively, the accuracy is 97.8%, 77. 5%, 85.4%, 94. 4% respectively,tested by pyrosequencing. The results of the detection of resistance to rifampin, isoniazid, ofloxacin and amikacin in Mycobacterium tuberculosis using pyrosequencing technique were almost the same with that of Bactec 960, and Kappa ≥0. 7 in each detection. Conclusion Pyrosequencing is thus a rapid, accurate and high throughput method for detecting Mycobacterium tuberculosis resistance to these four drugs.

Objective To study the relationship of two variants( -871A/G and -336A/G) polymorphisms of the DC-SIGN gene with the susceptibility to pulmonary tuberculosis in Chinese population.Methods Two hundred and thirty-seven tuberculosis cases and 244 controls were genotyped by pyrosequencing in this case-control study. The analysis of the relationship of the -871A/G and -336A/G polymorphisms with their susceptibility of pulmonary tuberculosis(PTB) and the relationship of the two variants with their clinical correlation of tuberculosis was performed by chi-square test. Results The genotypic frequencies of A/G + G/G and A/A of - 871, 37.6%, 62.4% respectively in cases, and 43.4%, 56. 6%respectively in controls, had no significant difference in statistics. And the genotypic frequencies of A/G + G/G and A/A of -336, 12. 2% ,87.8% respectively in cases, and 14.3% ,85.7% respectively in controls, had also no statistical difference between two groups. Interestingly, a significant association is disclosed between the promoter variant - 336G allele and fever in patients ( P = 0. 037, OR = 0. 191, 95 % CI:0. 040-0. 907 ). Conclusion The single nucleotide polymorphism of -871A/G and -336A/G in DCSIGN gene promoter might not be associated with the susceptibility to tuberculosis in Chinese. Tuberculosis patients with -336G allele are significantly protected fever.

Pericytes are a very important cellular constituent of the blood-brain barrier.They play a regulatory role in brain angiogenesis,endothelial cell tight junction formation,blood-brain barrier differentiation,microvascular dynamic motion and structural stability.Pericytes exhibit unique functional characteristics in some diseases,such as cerebrovascular disease,neurodegenerative disease,neuroimmune disease and traumatic brain injury.This article reviews the roles of pericytes in the blood-brain barrier.

Objective To obtain DNA oligonucleotide aptamers which can specifically bind to MPT64 protein from Mycobacterium tuberculosis by SELEX(systematic evolution of ligands by exponential enrichment)technology. Methods A random ssDNA library with in vitro synthesized 78 nucleotides in length was subiected to 12 rounds of selection by SELEX method against MPT64 protein. The binding ability of the aptamers to the protein was examined by biotin-streptavidin-horseradish peroxidase system. Results The selective system used was as follows:in PCR amplification,annealing temperature was 65℃ and the concentration of Mg2+ was 1.5 mmol/L in optimizing library, and when preparation of ssDNA with asymmetrical PCR amplification, 0.75 mmol/L of Mg2+ was used. When using the plate for ELISA as the substrate for the selection, the pattern of electrophoretic band of PCR product after the tenth round selection became unitary and denser than that of the first round. The binding assay demonstrated that A value at 450 nm of the tenth round increased by 9.18 times as compared with that of the first round. The results showed that the affinities of the aptamers were different. The highest A value at 450 nm was 1.606, and the lowest 0.572. Conclusion A set of aptamers with considerable binding affinity to MPT64 protein are successfully picked out from the initial random DNA library.