BACKGROUND:Skeletal muscle satel ite cells are totipotential stem cells with multi-directional differentiation potential, locate in skeletal muscle interstitium, have a certain tolerance to ischemia and hypoxia, and are important cells in stem cellengineering.
OBJECTIVE:To establish a thrifty, convenient culture procedure and create a simple, efficient method to transfect skeletal muscle satel ite cells, and investigate genetic expression after the transfection for cellular cardiomyoplasty.
METHODS:Skeletal muscle satel ite cells were isolated from rabbit thigh and cultured. Their growth curves were determined by CKK-8 method. Grouped by different proportions of the plasmid and liposome, skeletal muscle satel ite cells were transfered by the enhanced green fluorescent protein plasmid based on liposome. After transfection, the efficiency and character of target genetic expression was determined.
RESULTS AND CONCLUSION:Satel ite cells were isolated, cultured and transfected successful y. In suitable ratio of plasmid and liposomes, the transfection efficiency reached up to above 35%. The target protein was expressed within 12 hours after transfection, reached maximum in 48-72 hours and decreased gradual y after one week. The expression stil could be observed two weeks latter. The enhanced green fluorescent protein plasmid conducted by cationic liposome could be transfered into skeletal muscle satel ite cells efficiently. The transfection efficiency was correlated closely to the ratio of plasmid and lipofectamine. The change of target gene expression depended on time.

BACKGROUND: Previous studies have found that skeletal muscle satellite cell transplantation can induce angiogenesisin myocardial infarction area, reduce infarct size and improve cardiac function. But the overall effect is not satisfactory.OBJECTIVE: To observe the survival of basic fibroblast growth factor (bFGF) gene modified skeletal muscle satellitecells in acute myocardial infarction and to observe the expression of bFGF gene and the effect of cell transplantation onangiogenesis in myocardial infarction area.METHODS: Eighteen New Zealand white rabbits were divided into three groups by random: skeletal muscle satellite cellgroup (control group), bFGF gene enhanced skeletal muscle satellite cell group (experimental group) and blank controlgroup. The left anterior descending branch of the coronary artery of the rabbits was ligated so as to establish an animalmodel of acute myocardial infarction in the former two groups. After labeled by DAPI before transplantation, the skeletalmuscle satellite cells, bFGF gene modified skeletal muscle satellite cells and the equivalent amount of DMEM/F12 wereinjected into the local infarct myocardium correspondingly. Samples were taken 4 weeks after transplantation. Then, thesurvival of skeletal muscle satellite cells and the expression of bFGF gene were observed under light microscope andfluorescence microscope, and the neovascularization in the myocardial infarction area was examined byimmunohistochemical staining.RESULTS AND CONCLUSION: No DAPI-labeled cells were visible in the blank control group, but in the other twogroups, a large amount of DAPI-labeled skeletal muscle satellite cells were seen in the infarction area. Enhanced greenfluorescent protein was highly expressed in the experimental group. Microvessel density in the infarction area washighest in the experimental group followed by the control and blank control groups (P < 0.05). These findings indicatethat bFGF gene modified skeletal muscle satellite cells can survive and promote neovascularization in the acutemyocardial infarction area.

Objective To observe the effects of high-fat diet on liver steatosis and liver endoplasm reticulum stress in mice and to investigate the interventional effect of metfomin on them.Methods Forth-five male C57BL/J6 mice were divided into healthy control group,high-fat group and metformin group.High fat group and metformin group were fed with high-fat diet.Mice in metformin group were given metformin since the fourth week of high-fat feeding.After feeding for eight weeks,subperitoneal glucose tolerance test was performed in mice.After mice were sacrificed,liver triglyceride (TG) content and the expression of endoplasmic reticulum stress related factors at gene and protein levels were measured.One-way ANOVA was applied for analysis between groups.Results Compared with healthy control group,area under curve (AUC) of glucose tolerance and TG contents in liver tissues significantly increased in high-fat group [998±87 vs 1409±106,(10.05±0.29) μmol/g vs (27.11 ±4.76) μmol/g].Glucose tolerance and liver steatosis were improved in metformin group,AUC and TG of metformin group were significantly lower than those of high-fat group in metformin group [1178±90,(15.12±2.11) μmol/g,F=55.328,89.212,both P ＜0.01].Compared with healthy control group,the expression of glucose-regulated protein 94 (GRP94)at mRNA level significantly increased in high-fat group.Meanwhile,the expression of phosphorylated eukaryotic translation initiation factor 2α at protein level,which indicated endoplasmic reticulum stress,significantly increased.However,the expression of those endoplasmic reticulum stress markers at mRNA and protein level of metformin group were both lower than those of high fat group (F=84.002,137.321,both P＜0.05).Conclusions High fat diet caused liver steatosis in mice and accompanied by endoplasmic reticulum stress.Fatty liver was significantly improved by metformin treatment in high-fat-fed mice.The mechanism may be related with the improvement of endoplasmic reticulum stress by metformin.

Objective To explore the impact of broad antigen HLA-Bw4 on disease progression in HIV-1 infected subjects. Methods Three hundred and forty subjects chronically infected with HIV-1 and 69 HIV-1 negative subjects were recruited and HLA-B alleles were typed with sequence-based high resolution typing assay. HLA-Bw genotypes of these HIV-1 infected subjects were determined and their association with CD4+ T cell counts and viral loads were analyzed. Results Sixty-five HLA-B alleles were detected in HIV-1 positive subjects. Subjects with Bw4 (Bw4 homozygotes and Bw4Bw6 heterozygotes ) had higher CD4+ T cell counts ( P = 0. 004 ) and lower plasma viral load ( P = 0.003 ) than subjects without Bw4 ( Bw6 homozygotes). When compared with HIV-1 postive subjects with CD4+ T cell counts above 500 celis/μl, those with CD4+ T cell counts below 500 cells/μl were observed with decreased percentage of Bw4Bw6 heterozygote ( P =0.0002) and increased percentage of Bw6 homozygotes ( P < 0. 0001 ). There is no significant difference in CD4+ T cell counts between Bw4 homozygotes and Bw4Bw6 heterozygote, but lower viral loads were observed in Bw4Bw6 heterozygotes( P = 0. 037 ). Conclusion HLA-Bw4 can confer pretective effects on H1V-1 infected subjects by maintaining higher CD4+ T cell counts and lower viral load, the mechanism behind this effect need further exploration.

Objective To explore the possible relationship between alteration of cell cycle and JAK/STAT3 signal transduction pathway inhibition induced by arsenic trioxide (As_2O_3,) in myeloma cell lines U266 and RPMI8226 in vitro. Methods Multiple myeloma cell lines U266 and RPMI8226 were used as in vitro models. The influence of AS_2O_3 on myeloma cells were evaluated by MTT assay and flow cytometry. Meanwhile, methylation specific PCR and Western blotting were employed to detect the methylation status of gene SOCS-1 and protein expression level of P-STAT3 in these cells after AS_2O_3 treatment. Results AS_2O_3 significantly inhibited the growth of U266 and RPMI8226 cells in a dose-dependent manner. Furthermore, cell cycle was arrested at G0/G1 phase with inhibition of protein expression level of P-STAT3 and SOCS-1 gene demethylation after exposure to As_2O_3 for 72 h( r = 0. 85, P < 0.05). Conclusion AS_2O_3 could induce the alteration of cell cycle which might be related to JAK/STAT3 signal transduction pathway inhibition and SOCS-1 demethylation in myeloma cell lines. The study puts forward a new idea of AS_2 O_3 treatment in multiple myeloma.

Objective To compare the therapeutic effect of video-assisted thoracoscopic surgery and traditional thoracotomy in fixation of traumatic multiple rib fractures.Methods Clinical data of 56 patients with traumatic multiple rib fractures treated surgically between July 2005 and September 2012 were analyzed retrospectively.Based on the treatments,the patients were assigned to video-assisted thoracoscopy group (thoracoscopy group,n =27) and traditional thoracotomy group (thoracotomy group,n =29).A comparison was done on the variables including operation time,intraoperative blood loss,ventilator support rate,duration of mechanical ventilation,length of ICU stay,incidence of lung infections,visual analogue scale (VAS) at day 3 postinjury and mortality between the two groups.Results Operation time [(128.9 ± 21.1) min vs (140.7 ± 24.2) min],ventilator support rate (70％ vs 76％) and mortality (4％ vs 7％) in thoracoscopy group revealed no statistical differences compared with thoracotomy group (P ＞ 0.05),but intraoperative blood loss [(321.1 ± 30.1)ml vs (438.1 ± 43.2)ml],duration of mechanical ventilation [(4.3 ± 2.1) d vs (7.2 ± 1.6) d],length of ICU stay [(5.9 ± 21.1) d vs (8.5 ± 1.7) d],incidence of lung infection (33％ vs 90％),and VAS [(7.0 ± 1.4) points vs (8.3 ± 0.9) points] were significantly reduced in thoracoscopy group than in thoracotomy group (all P ＜ 0.01).Conclusion Video-assisted thoracoscopic surgery is characterized by fewer intraoperative bleeding,shorter duration of mechanical ventilation and ICU stay,and lower lung infection rate during treatment of traumatic multiple rib fractures compared to traditional thoracotomy.

Objective To analyze the MR manifestations of the focal nodular hyperplasia (FNH)in liver and observe the MRI changes after 30-36 months.Methods 12 (14 lesions)of the 13 patients (1 5 lesions)were firstly diagnosed as FNH by MRI with plain scan and dynamic Gd-DTPA enhancement,and then were confirmed by the follow-up survey with similar MRI after 30 - 36 months.The last one patient was also scanned with Gd-EOB-DTPA enhancement but with similar plain scans.The size,signal,en-hancement patterns of the lesions were analyzed and compared with those in the follow-up survey.Results Typical MR manifesta-tions were found in 93.33%(14/1 5)of the lesions with hypo-or iso-intensity on T1 WI,hyper-or iso-intensity on T2 WI,marked en-hancement in arterial phase and attenuation but still equal to or higher than normal liver parenchyma in portal and delayed phases af-ter Gd-DTPA administration.In addition,the central scar showed hypointensity on T1 WI,hyperintensity on T2 WI,and enhance-ment in delayed phase.The enhanced small vessels inside lesions and the pesudocapsule enhancement could be seen in delayed phase. The only one lesion with Gd-EOB-DTPA enhancement showed marked enhancement in arterial and portal phases,and slight hyperin-tensity in hepatocellular phase with hypo-intense central scar in any phases.As for the only one lesion with atypical manifestation,it showed isointensity on T1 WI,slightly hyperintensity on T2 WI,nonenhancement in arterial phase,slightly enhancement in portal phase,and small vascular enhancement inside the lesion in delayed phase.After the follow-up survey of 30-36 months 92.86%(13/14)lesions did not change,however one lesion (10mm)disappeared.Conclusion Typical FNH shows similar MRI characteristics, iso-intense or slightly hypo-intense signal on T1 WI,iso-intense or slightly hyper-intense signal on T2 WI,marked enhancement in ar-terial phase,the central scar enhancement and the inside small vascular enhancement of lesions in delayed phase.It is valuable in dif-ferential diagnosis.

Objective:To discuss the influence of mindfulness-based stress reduction plus micro-class education on the complications and knowledge mastery rate in surgical patients with diabetes mellitus.Methods:A total of 105 patients, diagnosed as diabetes mellitus complicated with appendicitis in the Affiliated Hospital of Chengde Medical College were selected from January 2019 to January 2020. They were hospitalized for laparoscopic appendectomy and were randomly divided into the control group ( n = 52) and the study group ( n = 53) in accordance with the random number table. The patients in the control group were given routine nursing care, and the patients in the study group were given mindfulness decompression therapy combined with micro-classroom education. The blood glucose control and psychological emotion of the two groups before and after operation, and the postoperative complications and the mastery rate of disease knowledge of the two groups were compared. Results:There was no significant difference in blood glucose indexes between the two groups at baseline ( P>0.05); FBG, HbA1c and other indicators in the two groups were improved during operation and 24h after operation, but FBG (7.38±0.54) mmol/L, HbA1c (6.39±0.21)% and FBG (6.90±0.52) mmol/L and HbA1c (6.10±0.39)% in the study group were lower than those in the control group [(8.16±1.21) mmol/L, (7.53±1.05)%, (7.60±0.57) mmol/L, (6.50±0.41)%], the difference was statistically significant ( t value was 6.789-13.264, P < 0.05); there was no significant difference in SAS and SDS scores between the two groups at baseline ( P > 0.05), until discharge, the SAS and SDS scores of the treatment group were 35.81±5.49 and 42.08±4.91 respectively, which were significantly lower than those of the control group (42.21±5.53, 6.51±4.72) respectively, compared with the corresponding scale scores of the control group, the difference between the two groups after treatment was statistically significant ( t value was 5.386, 4.265, P < 0.05). Compared with 17.31% (9/52) of the control group, the incidence of complications in the study group decreased to 5.66% (3/53), there was significant difference ( χ2 value was 6.789, P < 0.05). The qualified rate of disease knowledge mastery in the study group (98.11%,52/53) was significantly higher than that in the control group (86.53%, 45/52), and the difference was significant ( χ2 value was 5.062, P < 0.05). Conclusion:The mindfulness-based stress reduction plus micro-class education can effectively control the laparoscopic appendectomy patients blood glucose, stabilize the mental emotions, increase the illness knowledge mastery degree, keep in good mood, reduce the postoperative complications and promote the fast recovery.

Objective To assess the impact of the virus on the complementary determining region 3 (CDR3) length diversity of T cell receptor(TCR) Vβ repertoires of CD4+ T lymphocytes and to explore its association with viral load in individuals with HIV-1 infection. Methods The TCR repertoire was examined using spectratyping of CDR3 length diversity within CD4+ T cells in HIV infected and healthy adults. Separation of CD4+ T cells from peripheral blood mononuclear cells ( PBMCs) was carried out by using immunomagnetic beads coated with anti-CD4 antibody. Total RNAs from the purified CD4 + T lymphocytes were isolated and used to perform nested-PCR amplifications in CDR3 of 22 TCR gene families. CDR3 diversity and its association with viral load in individuals with HIV-1 infection were analyzed. Results An average diversity for all CDR3 profiles in CD4+ T cells from 25 HIV-infected individuals was significantly different as compared to 10 age-matched healthy donors (P＜0.05) with the HIV-infected individuals losing diversity in the CDR3 profiles. There was positive correlation between changes in TCR CDR3 diversity and viral load (r = 0. 494, P ＜ 0. 05). The changes in CDR3 length diversity of Vβ families in HIV-infected individuals, particular in Vβ8, Vβ22, Vβ23 were statistically different from the healthy controls. Conclusion HIV-1 infection might induce the loss of TCR Vp repertoire diversity and disrupt the CDR3 Gaussian distributions within CD4 + T cells. There should be positive correlation between changes in TCR CDR3 diversity and the viral load in HIV-1 infected patients.

Objective To explore the polymorphism of HLA class I alleles of HIV-infected former plasma donors and to investigate its impact on HIV-1 viral load in central China.Methods 106 subjects chronically infected with HIV-1 were recruited and HLA class I alleles were genotyped with PCR-SSP assay.HLA class I genotypes and haplotypes were determined and their association with plasma viral loads were analyzed.Gag-specific CTL responses were detected by an IFN-λ EUSPOT assay by using overlapping peptides,and their association with plasma viral loads were also analyzed.Results Subjects homozygous at HLA class I locus had higher plasma viral loads(P=0.0098);HLA-A*30,-B*13,-Cw*06,-Cw*14 alleles and HLA-A*30/B*13/Cw*06 haplotype were associated with lower plasma viral loads(P=0.0004,0.0103,0.0058,0.0371 and 0.0006);an inverse correlation between p2p7p1p6-specific CTL responses and viral loads in subjects with HLA-A*30/B*13/Cw*06 haplotype as well as an inverse correlation between p17-specific CTL responses and viral loads in subjects with HLA-Cw*14 allele were observed.Conclusion HLA-A*30,-B*13,-Cw*06,-Cw*14 alleles and HLA-A*30/B*13/Cw*06 haplotype were associated with lower plasma viral loads and Gag-specific CTL responses restricted by these HLA alleles may contribute to the protection.