Biomedical subjects

Dalong Ma

Publications and source records attributed to Dalong Ma.

42 records · Page 3Linked to original sources

PubMed2002

[Detection and analysis of Helicobacter pylori in oral cavity and stomach from chronic gastritis patients].

OBJECTIVE: To investigate the prevalence of Helicobacter pylori (Hp) in the oral cavity of gastritis patients and analyze the genotype similarity of Hp in the oral cavity with that in the stomach. METHODS: A total of 384 plaque samples were collected from 32 patients with chronic gastritis and chronic periodontitis, one supragingival plaque sample and one subgingival plaque sample from one tooth, totally 6 teeth having been examined for one patient. Gastric biopsy specimens were collected by gastroscopy, four pieces of specimen for one patient, to undergo rapid urease test, histopathology, and Warthin-Starry silver staining. PCR assay was conducted on each specimen with primers based on the sequences of urease C gene and cag A gene specific to Hp to amplify the 294-bp and 400-bp DNA fragments. The identity of amplified products was confirmed by restriction endonuclease digestion. Two PCR positive products (Hp urease C gene 294 bp fragments) from the dental plaque samples and one gastric biopsy specimen from one of the four patients in the same family, totalling 12 specimens, were further examined by single-strand conformation polymorphism (SSCP). RESULTS: Twenty-seven patients (84.4 %) had at least one Hp positive dental plaque sample. In total, 113 (29.4%) of the 384 tested samples were urease C gene positive and 9 (2.3%) were positive for both urease C gene and cag A gene. The Hp positive rate was significantly higher in subgingival plaque (71/192, 37%) than in supragingival plaque (42/192, 21.9 %) (P < 0.01). The Hp positive rate in dental plaque was 57.1% (48/84) at the gingiva with the probing depth (PD) >/= 4 mm, significantly higher than that at the gingiva with the PD < 4 mm (34.3%, 37/108,P < 0.05). The Hp positive rate in the specimens of gastric mucosa was 96.7% (31/32). The Hp in the 12 dental plaque specimens and gastric biopsy specimens from the 4 patients in the same family had 3 banding patterns all together. One of the patients had at least one identical banding pattern in both the plaque specimens and gastric biopsy specimens. One specific banding pattern was found in the Hp from the dental plaques of all 4 patients. In one patient, the SSCP banding pattern in the Hp from dental plaque was inconsistent with that from gastric biopsy specimens. CONCLUSION: Hp exists in the oral cavity of gastritis patients. Oral Hp infection may be an important source of gastric Hp infection. Familial clustering and oral-oral transmission of Hp infection exist.

Adult↗

PubMed2002

[Effect of interleukin I receptor antigonist gene therapy on arthritis induced by type II collagen in mice].

OBJECTIVE: To investigate the effect of interleukin-1 receptor antagonist gene therapy on type II collagen induced arthritis in DBA/1 mice. METHODS: Plasmid pcDI-IL-1ra that expresses IL-1ra in eukaryotes was constructed by inserting human IL-1ra cDNA into the eukaryotic expression vector pcDI. Eukaryotes were transfected with the plasmid pcDI-IL-1ra in vivo and in vitro. The expression of 8 IL-1ra was examined by ELISA and immunohistochemistry. Type II collagen was used to induced arthritis in 32 DBA/1 mice. This plasmid was injected into the muscles of DBA/1 mice with arthritis induced by type II collagen by gene gun (20 micro g/mouse) and into the muscle of 8 mice by intramuscular injection (200 micro g/mouse). After the administration, the condition of arthritis was observed. The serum IL-ira was examined 6 and 12 days after administration. The expression of IL-ira in muscles was tested by computerized imaging analysis. RESULTS: PCR and DNA sequencing proved the accuracy of the inserted fragment. ELISA and immunohistochemistry detected high expression of IL-ira in vivo and in vitro. The absorbance ( A ) 490 value of IL-ira in the mouse muscle was 0.52 +/- 0.03 in gene gun group, and 0.48 +/- 0.02 in intramuscular injection group, all higher than that in the control group (0.41 +/- 0.02,P < 0.01 and P < 0.05). The serum IL-ira values in the gene gun group and in tramuscular injection group 6 days and 12 days after therapy were all significantly higher than that in the control group (all P < 0.01; and P < 0.01 and P < 0.05). Since the 6 th day after therapy, the redness and swelling of joints in both therapies groups were alleviated. Pathological examination made 12 days after therapy showed relief at different degrees of the infiltration of inflammatory cells, hyperplasia of synovia, bone infiltration, and cartilage destruction, especially in the gene gun group. CONCLUSION: Gene therapy of IL-ira via non-virus eukaryotic expression vactor, especially by gene gun, is effective in treating arthritis induced by type II collagen.

Animals↗

PubMed2002

Expression of human VEGF(121) cDNA in mouse bone marrow stromal cells.

OBJECTIVE: To construct a retroviral vector carrying human vascular endothelial growth factor (hVEGF (121)) cDNA for evaluation of the possibility of VEGF gene therapy in ischemic bone disease. METHODS: hVEGF(121) cDNA was obtained from the plasmid pCDI/VEGF(121) and cloned into retroviral plasmid pLXSN. Recombinant plasmid was transferred to the retro virus packaging cell, PT-67, by lipofectamine mediated gene transfer. Mouse bone marrow stromal cells (MSCs) were transfected by the retrovirus. The integration of the hVEGF(121) cDNA into MSC genomic DNA and expression of the VEGF gene was detected. Proliferation assays of human umbilical vein endothelial cells (HUVECs) by VEGF(121) in culture medium were performed. RESULTS: Recombinant pLXSN/VEGF(121) was correctly constructed and confirmed by restriction endonuclease analysis and DNA sequencing analysis. hVEGF(121) gene was integrated into MSC genomic DNA after transfection, and the VEGF(121) protein was expressed. Proliferation assays showed VEGF(121) in culture medium was a biologically active protein and had a mitogenic effect on HUVEC. CONCLUSIONS: Recombinant retroviral vector carrying hVEGF(121) cDNA was successfully constructed. VEGF (121) protein expressed by MSCs had mitogenic effect biologically. This provides a further foundation for VEGF gene therapy for bone ischemic disease and bone tissue engineering.

Animals↗

PubMed2002

[Construction of adenoviral vector encoding human VEGF(121) cDNA and its expression in vitro].

OBJECTIVE: To construct the adenoviral vector bringing hVEGF(121) cDNA for evaluation of the possibility of VEGF gene therapy in ischemic bone disease. METHODS: Human vascular endothelial growth factor (hVEGF(121)) cDNA obtained from the plasmid pCDI/VEGF(121) was cloned into plasmid pshuttle and further cloned to Adeno-X Viral DNA. The recombinant adenoviral plasmid was identified and then transferred to the adenoviral packaging cell HEK293 by lipofectamine mediated gene transfer method to pack the virus. After titilating the virus, the mouse bone marrow stromal cells (MSC) were transfected by the adenovirus and the expression of VEGF gene was detected. RESULTS: The recombinant Adeno-VEGF(121) was correctly constructed and confirmed by restriction endonuclease analysis and DNA sequencing analysis. After MSCs were tranfected by the virus, RT-PCR showed that hVEGF(121) mRNA was transcripted from the hVEGF(121) gene. Western blot and immune histochemistry showed VEGF(121) protein was expressed in transgene MSCs. CONCLUSION: The recombinant adenoviral vector bringing hVEGF(121) cDNA was successfully constructed and the transgene MSC expressed hVEGF gene in vitro, it provided the further foundation of VEGF gene therapy for bone ischemic diseases.

Adenoviridae↗

PubMed2002

[Expression of IL-6 in recombinant non-replicating vaccinia virus and studying its effects on immunogenicity].

BACKGROUND: To investigate expression of IL-6 in non?replicating vaccinia virus and its immune effects on recombinant virus. METHODS: The recombinant non replicating vaccinia virus RVJ123 delta CK11 beta 75IL6 was constructed with non?replicating vaccinia virus vector pNEOCK11beta75IL6 and replicating vaccinia virus RVJ123. In animal model, immunization with the recombinant virus was carried out and its immune response was studied. RESULTS: The recombinant virus could express IL-nd HBsAg simultaneously. Southern blot analysis demonstrated that the genes between vaccinia virus Hind? C and K fragments were deleted and IL-6 gene was integrated stably. Given intranasal inocula of the virus to immunize BALB/c mouse and New Zealand Rabbit, the elevated anti-HBsAg IgA and IgG antibody secreting cells in mouse lung lymphoid to vectors expressing IL-6 was at about two?fold higher level than those elicited by control virus at day 14 after immunization. Authors also could detect elevated anti-HBsAg IgA and IgG antibody conversion in mouse serum and lung fluid, rabbits serum, lung fluid, saliva, vagina and nasal washing samples. CONCLUSIONS: IL-6 expressed by non-replicating recombinant vaccinia virus could enhance the induced?immune effects, it could serve as the effective adjuvant for recombinant vector vaccine.

Adjuvants, Immunologic↗

PubMed2000

[Expression of TFAR19 in Apoptotic Processes of Jurkat Cells Induced with Various Methods]

A new apoptosis-related gene TFAR19 was recently cloned. A primary functional analysis indicates its role in the apoptotic process of TF-1 cells. To clarify TFAR19 was involved in which apoptotic pathway, the changes in TFAR19 expression were observed during the apoptotic processes of Jurkat cells induced with various methods: serum deprivation, VP-16 treatment and Fas McAb activation. Then TFAR19 expression in Jurkat cells was detected with flow cytometry and Western blot, and TFAR19 mRNA with RT-PCR. Our results showed that expression of TFAR19 in Jurkat cells was increased at 12 hours after serum deprivation, 2 hours after VP-16 treatment and 2 hours after Fas McAb activation, respectively. These observations suggested that TFAR19 was involved in the apoptotic process of Jurkat cells induced with serum deprivation, DNA destruction and death receptor activation. It might take effect in the early apoptotic process. TFAR19 is a participant of the "final common pathway" in the apoptotic pathway.

Journal Article↗