1.Construction of genetic recombinant adenovirus carrying human growth and differentiation factor-5 gene by using AdEasy-1 adenovirus vector system
Xuwei LUO ; Kang LIU ; Zhu CHEN ; Ming ZHAO ; Xiaowei HAN ; Yiguang BAI ; Gang FENG
Chongqing Medicine 2014;(12):1412-1415
Objective To construct the genetic recombinant adenovirus vector carrying the human growth and differentiation fac-tor-5(GDF-5) gene by using AdEasy-1 adenovirus vector system and to amplify and prepare the recombinant adenovirus in HEK 293 cells .Methods Human GDF-5 gene obtained by PCR was inserted into plasmid pMD19-T and the 1 .7 kb GDF-5 cDNA sequence was cloned into the adenoviral shuttle plasmid pShuttle-cytomegalovirus(CMV) of the AdEasy-1 system .It was identified by DNA sequencing and a digestion with Hind Ⅲ restriction enzyme .The resultant pShuttle-CMV-GDF-5 was used to generate the adenovi-ral GDF-5 vector through homologous recombination with the adenoviral backbone plasmid ,pAdEasy-1 in BJ5183 bacterial cells .It was selected by kanamycin and identified by a digestion with Hind Ⅲ restriction enzyme and amplified in XL10-Gold competent bac-teria .The DNA of recombinant adenovirus vector was finally linearized by Pac Ⅰ and the adenoviral recombinants were used to pro-duce adenoviruses in HEK293 packaging cells ,resulting in an Ad-GDF-5 identified by Western blot .The virus titer was assayed by TCID50 .Results GDF-5 cDNA sequence obtained by PCR was 1 .7 kb .Gene sequencing results indicated that the sequence was i-dentical with the one in GENBANK .Cloned sequence 1 .7 kb(GDF-5) was obtained by a digestion with Hind Ⅲ restriction enzyme after GDF-5 cDNA segment was cloned into pShuttle-CMV and AdEasy-1 .Western blot showed that two bands migrating at ap-proximately 15 and 55 kDa were clearly observed in PVDF membrane .These data confirmed that HEK293 cells expressed a large number of mature GDF-5 protein after infected with Ad-GDF-5 .Our research results demonstrated that recombinant adenovirus vector GDF-5 was successfully constructed .The virus titer was 5 .6 × 109 PFU/mL .Conclusion Recombinant adenovirus vector carrying the human GDF-5 gene is successfully constructed by using the AdEasy-1 adenovirus vector system .Moreover ,the Ad-GDF-5 with high titer is prepared .These provide the basis for further study of the biological function of GDF-5 and the gene thera-py of its related diseases .
2.Correlation between the replacing time of plasma drainage bag and the bacterial growth rate
Jiemin ZHANG ; Xinghua YANG ; Subi HUANG ; Kang LIU ; Ke CHEN ; Qingxia WU ; Yiguang BAI
Chinese Journal of Modern Nursing 2014;20(11):1282-1285
Objective To explore the correlation between the replacing time of plasma drainage bag and the bacterial growth rate among orthopaedic surgery patients , and to control or reduce the risk of catheter-related infection.Methods The convenient sampling method was used to select 100 patients with postoperative serum drainage tube and disposable drainage bag , from September 2012 to August 2013.Patients were randomly divided into the control group (group A, 33 cases) and the observation group (group B, 32 cases; group C, 35 cases).The amount of drainage were recorded every 24 hours of the three groups of patients , and then the drainage bags were emptied .Group A replaced the drainage bag regularly every day; Group B replaced the drainage bag every 48 hours;Group C did not replace the drainage bag .The outside mouth of the drainage tube and the drainage liquid were taken to bacterial culture . The positive rate of bacterial culture , patients'postoperative body temperature and the rate of incision infection were compared within groups .Results Twenty-four hours after operation, the results of bacterial culture among three groups were negative .However, after 48 hours, six patients (18.1%) in group A, two patients (6.4%) in group B showed positive results of the bacterial culture .None of the patients in group C had the positive results .The comparison among three groups was statistically significant (χ2 =10.32,P<0.05).After 72 hours, eight patients (24.2%) in group A, two patients (6.4%) in group B showed positive results of the bacterial culture .None of the patients in group C had the positive results.The comparison among three groups was statistically significant (χ2 =11.82,P<0.05). The incidence of incision infection of group A , group B and group C were 15.1%(5/33), 6.3%(2/32) and 0.0%(0/35), respectively.There was a significant difference among three groups (χ2 =11.18,P<0.05).The body temperature of the three groups showed no significant difference (F=7.53,P>0.05).Conclusions With the increase of drainage bag replacement frequency , the positive rate of bacterial culture , as well as the drainage bag and drainage tube mouth bacteria culture positive rate increase .Therefore, for orthopaedic patients , the plasma drainage tube and disposable drainage bag should be emptied every 24 hours after the measurement of drainage liquid, but do not have to be replaced every 48 hours or every 24 hours.
3.Changes in the gut microbiota of osteoporosis patients based on 16S rRNA gene sequencing: a systematic review and meta-analysis.
Rui HUANG ; Pan LIU ; Yiguang BAI ; Jieqiong HUANG ; Rui PAN ; Huihua LI ; Yeping SU ; Quan ZHOU ; Ruixin MA ; Shaohui ZONG ; Gaofeng ZENG
Journal of Zhejiang University. Science. B 2022;23(12):1002-1013
BACKGROUND: Osteoporosis (OP) has become a major public health issue, threatening the bone health of middle-aged and elderly people from all around the world. Changes in the gut microbiota (GM) are correlated with the maintenance of bone mass and bone quality. However, research results in this field remain highly controversial, and no systematic review or meta-analysis of the relationship between GM and OP has been conducted. This paper addresses this shortcoming, focusing on the difference in the GM abundance between OP patients and healthy controls based on previous 16S ribosomal RNA (rRNA) gene sequencing results, in order to provide new clinical reference information for future customized prevention and treatment options of OP. METHODS: According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), we comprehensively searched the databases of PubMed, Web of Science, Embase, Cochrane Library, and China National Knowledge Infrastructure (CNKI). In addition, we applied the R programming language version 4.0.3 and Stata 15.1 software for data analysis. We also implemented the Newcastle-Ottawa Scale (NOS), funnel plot analysis, sensitivity analysis, Egger's test, and Begg's test to assess the risk of bias. RESULTS: This research ultimately considered 12 studies, which included the fecal GM data of 2033 people (604 with OP and 1429 healthy controls). In the included research papers, it was observed that the relative abundance of Lactobacillus and Ruminococcus increased in the OP group, while the relative abundance for Bacteroides of Bacteroidetes increased (except for Ireland). Meanwhile, Firmicutes, Blautia, Alistipes, Megamonas, and Anaerostipes showed reduced relative abundance in Chinese studies. In the linear discriminant analysis Effect Size (LEfSe) analysis, certain bacteria showed statistically significant results consistently across different studies. CONCLUSIONS: This observational meta-analysis revealed that changes in the GM were correlated with OP, and variations in some advantageous GM might involve regional differences.
Middle Aged
;
Aged
;
Humans
;
Gastrointestinal Microbiome/genetics*
;
RNA, Ribosomal, 16S/genetics*
;
Genes, rRNA
;
Osteoporosis
;
Feces
4.Short-chain fatty acids ameliorate spinal cord injury recovery by regulating the balance of regulatory T cells and effector IL-17+ γδ T cells.
Pan LIU ; Mingfu LIU ; Deshuang XI ; Yiguang BAI ; Ruixin MA ; Yaomin MO ; Gaofeng ZENG ; Shaohui ZONG
Journal of Zhejiang University. Science. B 2023;24(4):312-325
Spinal cord injury (SCI) causes motor, sensory, and autonomic dysfunctions. The gut microbiome has an important role in SCI, while short-chain fatty acids (SCFAs) are one of the main bioactive mediators of microbiota. In the present study, we explored the effects of oral administration of exogenous SCFAs on the recovery of locomotor function and tissue repair in SCI. Allen's method was utilized to establish an SCI model in Sprague-Dawley (SD) rats. The animals received water containing a mixture of 150 mmol/L SCFAs after SCI. After 21 d of treatment, the Basso, Beattie, and Bresnahan (BBB) score increased, the regularity index improved, and the base of support (BOS) value declined. Spinal cord tissue inflammatory infiltration was alleviated, the spinal cord necrosis cavity was reduced, and the numbers of motor neurons and Nissl bodies were elevated. Enzyme-linked immunosorbent assay (ELISA), real-time quantitative polymerase chain reaction (qPCR), and immunohistochemistry assay revealed that the expression of interleukin (IL)-10 increased and that of IL-17 decreased in the spinal cord. SCFAs promoted gut homeostasis, induced intestinal T cells to shift toward an anti-inflammatory phenotype, and promoted regulatory T (Treg) cells to secrete IL-10, affecting Treg cells and IL-17+ γδ T cells in the spinal cord. Furthermore, we observed that Treg cells migrated from the gut to the spinal cord region after SCI. The above findings confirm that SCFAs can regulate Treg cells in the gut and affect the balance of Treg and IL-17+ γδ T cells in the spinal cord, which inhibits the inflammatory response and promotes the motor function in SCI rats. Our findings suggest that there is a relationship among gut, spinal cord, and immune cells, and the "gut-spinal cord-immune" axis may be one of the mechanisms regulating neural repair after SCI.
Animals
;
Rats
;
Interleukin-17
;
Rats, Sprague-Dawley
;
Recovery of Function
;
Spinal Cord Injuries/drug therapy*
;
T-Lymphocytes, Regulatory
;
Receptors, Antigen, T-Cell, gamma-delta/immunology*