The up-regulation mechanism of membrane type I matrix metalloproteinase (MT1-MMP) in macrophages stimulated by silica in vitro and the contribution of early growth response 1 (Egr-1) transcription factor in the gene expression pathway were investigated. Macrophages stimulated by silica were treated with Egr-1 antibody or Egr-1 decoy oligodeoxynucleotides (ODN). The levels of MT1-MMP proteins were determined by Western blot and the expression of MT1-MMP mRNAs was detected by RT-PCR. The results showed as compared with control macrophages, silica-stimulated group showed up-regulated gene expression of MT1-MMP via Egr-1 (P<0.01). Compared with silica-stimulated macrophages untreated with antibody, the cells treated with 5 μg/mL Egr-1 antibody were associated with reduced expression of MT1-MMP protein (P<0.01) and mRNA (P<0.01). Compared with silica-stimulated untransfected group, the Egr-1 “decoy” ODN group was associated with reduction in the expression of MT1-MMP protein and mRNA (P<0.01). It was concluded gene expression of MT1-MMP which may play a critical role in silicosis was up-regulated by silica in macrophages. Egr-1 participated in the expression of MT1-MMP and positively regulated the expression. Both Egr-1 antibody and Egr-1 decoy ODN suppressed the expression of MT1-MMP through the Egr-1 pathway and may become a potential therapeutic tool in the management of silicosis in the future.

To investigate the enhancement of immunological activity of CpG ODN by chitosan gene carrier in mice, the effect of lymphocyte proliferation was detected in mice by using MTT, the levels of IgG and cytokines (IL-2 and IL-12) in serum were measured by ELISA and peripheral blood T lymphocyte subsets CD4⁺, CD8⁺ were analyzed by flow cytometry. Our results showed that spleen lymphocytes isolated from the CS-CpG ODN group of mice showed the strongest proliferation (SI=1.551), and the levels of IgG, IL-2 and IL-12 in serum were higher than those of other groups. Compared with the immunization with CpG ODN, the immunization with CS-CpG ODN gene carrier was more efficient in up-regulating the percentage of CD4⁺T cells and the ratio of CD4⁺/CD8⁺ of mice. It was concluded that CS gene carrier of CpG ODN was much more effective in improving immunity of CpG ODN in mice.

The human brain-derived neurotrophic factor (hBDNF) gene was cloned by polymerase chain reaction and the recombinant adeno-associated viral vector inserted with hBDNF gene (AAV-hBDNF) was constructed. Cultured rat hippocampal neurons were treated with Aβ_25–35 and serued as the experimental Aβ-induced neuronal damage model (AD model), and the AD model was infected with AAV-hBDNF to explore neuroprotective effects of expression of BDNF. Cell viability was assayed by MTT. The expression of bcl-2 anti-apoptosis protein was detected by immunocytochemical staining. The change of intracellular free Ca ion ([Ca²⁺]_i) was measured by laser scanning confocal microscopy. The results showed that BDNF had protective effects against A-induced neuronal damage. The expression of the bcl-2 anti-apoptosis protein was raised significantly and the balance of [Ca²⁺]i was maintained in the AAv-hBDNF treatment group as compared with AD model group. These data suggested that recombinant AAV mediated a stable expression of hBDNF in cultured hippocampal neurons and resulted in significant neuron protective effects in AD model. The BDNF may reduce neuron apoptosis through increasing the expression of the bcl-2 anti-apoptosis protein and inhibiting intracellular calcium overload. The viral vector-mediated gene expression of BDNF may pave the way of a novel therapeutic strategy for the treatment of neurodegenerative diseases such as Alzheimer’s disease.

This study evaluated the correlation between DNA degradation of the splenic lymphocytes and the early time of death, examined the early time of death by computerized image analysis technique (CIAT) and identified the best parameter that quantitatively reflects the DNA degradation. The spleen tissues from 34 SD rats were collected, subjected to cell smearing every 2 h within the first 36 h after death, stained by Feulgen-Van’s staining, three indices reflecting DNA content in splenic lymphocytes, including integral optical density (IOD), average optical density (AOD), average gray scale (AG) were measured by the image analysis. Our results showed that IOD and AOD decreased and AG increased over time within the first 36 h. A stepwise linear regression analysis showed that only AG was fitted. A correlation between the postmortem interval (PMI) and AG was identified and the corresponding regression equation was obtained. Our study suggests that CIAT is a useful and promising tool for the estimation of early PMI with good objectivity and reproducibility, and AG is a more effective and better quantitative indicator for the estimation of PMI within the first 36 h after death in rats.

In order to investigate the clinical value of vascular endothelial growth factor (VEGF) combined with interferon-γ (IFN-γ) in diagnosing malignant pleural effusion and tuberculous pleural effusion, 42 cases of malignant pleural effusion and 45 cases of tuberculous pleural effusion in Tongji Hospital, from March 2004 to May 2005, were included. The carcinoembryonic antigen (CEA), VEGF and IFN-γ levels of pleural effusion were detected by using ELISA, and adenosine deaminase (ADA) activity was determined by using enzyme kinetic analytical method. The sensitivity, specificity, accuracy and area under the curve (AUC^ROC) of CEA and VEGF, VEGF/IFN-γ ratio, ADA and IFN-γ were measured by receiver operating characteristic curve (ROC). The results showed that CEA, VEGF levels and VEGF/IFN-γ ratio were significantly higher and the ADA and IFN-γ levels were significantly lower in malignant group than those in tuberculous group (P<0.01). The sensitivity, specificity, accuracy and AUC^ROC of VEGF/IFN-γ ratio (88.7%, 99.8%, 94.4%, 0.96 respectively) were higher than those of CEA (67.8%, 96.1%, 82.4%, 0.78 respectively) and VEGF (81.5%, 84.3%, 82.9%, 0.79 respectively). The sensitivity, specificity, accuracy and AUC^ROC of IFN-γ (85.7%, 96.4%, 90.9%, 0.94 respectively) were higher than those of ADA (80.2%, 87.6%, 83.8%, 0.81 respectively). It was concluded that VEGF/IFN-γ ratio and IFN-γ could be used as valuable parameters for the differential diagnosis of malignant pleural effusion and tuberculous pleural effusion.

Pdx-1, an important transcription factor highlighting in the early pancreatic development, islet functions and pancreatic disorders, needs to be more investigated in zebrafish, and siRNA is still seldom applied in zebrafish embryo-related research. Our aim was to explore the role of pdx-1 in pancreatic development of zebrafish embryos by using siRNA approach. Microinjection, reverse transcriptase-PCR (RT-PCR), in situ hybridization and immunofluorescent staining were used in this research, and the morphology of the islet in normal zebrafish embryos, and in those treated with the siRNA specific to pdx-1 (siPDX-1) or siGFP was observed and compared. The expression of pdx-1 was detected in the stages of 1-cell, 2-cell, 4-cell, 8-cell, 16-cell, 16-hour by RT-PCT. The in situ hybridization and immunofluorescent staining results showed that siPDX-1 disturbed the formation of the islet in zebrafish embryos. Pdx-1 played multiple roles in maintaining the phenotype of the islet during embryogenesis in zebrafish.