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The humanitarian damage caused by the unexploded submunitions is one of the hot issues of concern to the international community at present. A portion of the submunition that did not explode was caused by a break at the connection between the ribbon riveting and the fuze. According to the physical structure of the submunition and the trajectory into which it was ejected, we analyzed the forces of the submunition in flight, deduced the related mathematical models, and clarify the key elements of the mechanics. In this paper, the commercial simulation software was used to calculate the mechanical properties of the ribbon. And the variation regularity between drop velocity and straightening force of ribbon are revealed. And the response characteristics of different material ribbon with different sizes of riveting holes and riveting joints under tensile action were simulated. The simulation results show that, in the trajectory environment with 30 m/s~55 m/s typical stream speed, the tensile force of the ribbon is less than 300 N, and the application concentration of the connecting parts of the riveting joint and the ribbon will not cause the failure of the kevlar ribbon, but it will cause the failure of the nylon ribbon. In order to verify the variation of the tension of kevlar ribbons in different trajectory environments, we designed the experimental scheme of tension test of the ribbon straightening section of submunition and conducted experiments. Experimental results and numerical simulation results revealed the same law. This paper provides effective technical support for solving the problem of unexploded submunitions. [ABSTRACT FROM AUTHOR]

Due to progress in the research of glioma stem cells and the glioma niche, development of an animal model that facilitates the elucidation of the roles of the host tissue and cells is necessary. The aim of the present study was to develop a subcutaneous xenograft green fluorescent protein nude mouse model and use this model to analyze the roles of host cells in tumor necrosis repair. Tumors derived from the human glioma stem/progenitor cell line SU3 were subcutaneously implanted in green fluorescent protein nude mice. The implanted tumors were then passed from animal to animal for 10 generations. Finally, subcutaneous xenografts were assayed with traditional pathology, immunopathological techniques and fluorescence photography. For each generation, the tumorigenicity rate was 100%. Subcutaneous xenografts were rich in blood vessels, and necrotic and hemorrhagic foci, which highly expressed hypoxia-inducible factor-1α, tumor necrosis factor, Ki-67, CD68 and CD11b. In the interstitial tissue, particularly in old hemorrhagic foci, there were numerous cells expressing green fluorescent protein, CD68 and CD11b. Green fluorescent protein nude mouse subcutaneous xenografts not only consistently maintained the high invasiveness and tumorigenicity of glioma stem/progenitor cells, but also consisted of a high concentration of tumor blood vessels and necrotic and hemorrhagic foci. Subcutaneous xenografts also expressed high levels of tumor microenvironment-related proteins and host-derived tumor interstitial molecules. The model has significant potential for further research on tumor tissue remodeling and the tumor microenvironment.

Objective: During the process of tissue remodeling in human tumor transplantation models, the roles of the inoculated tumor cells and host tissue in tumor progression is still largely unknown. The aim of this study was to investigate the relationships and interactions between these two sides using GFP-RFP double fluorescence tracing technique., Methods: Red fluorescence protein (RFP) gene was stably transfected into glioma stem cell line SU3, then SU3-RFP cells were transplanted into the brain of athymic nude mice with green fluorescence protein (GFP) expression. After the intracerebral tumors were formed, the relationship and interaction between GFP cells and RFP cells were analyzed. Highly proliferative GFP cells were screened out, and monocloned with micro-pipetting. DNA content assay, chromosome banding and carcinogenicity test of the GFP cells were performed to observe the GFP cells' cancerous phenotype in nude mice., Results: In the transplantable tumor tissue, besides a great quantity of RFP cells, there were still a proportion of GFP cells and GFP/RFP fusion cells. The proportion of RFP cells, GFP cells and GFP/RFP cells were (88.99 ± 1.46)%, (5.59 ± 1.00)%, and (4.11 ± 1.020)%, respectively. Two monoclonal host GFP cells (H1 and H9) were cloned, which demonstrated the properties of immortality, loss of contact inhibition, and ultra-tetraploid when cultured in vitro. Both H1 and H9 cells expressed CNP, a specific marker of oligodendrocytes. The GFP cells also demonstrated 100% tumorigenic rate and high invasive properties in vivo., Conclusions: In this glioma transplantation model, the transplanted tumor tissues contained not only transplanted glioma stem cells but also cancerous host GFP cells. Our findings offer important clues to further research on the relationships among different members in the tumor microenvironment.

Objective: To investigate the autoimmune injuries of diabetic macrovascular disease (aorta) and the protective effects of immunosuppressive agent (cyclosporine A, CsA) on aortic injuries in streptozotocin (STZ)-induced diabetic rats., Methods: STZ-induced diabetic rats were assigned randomly to 6 groups which received low (BML or AML, 1 mgxkg(-1)xd(-1)), middle (BMM or AMM, 4 mgxkg(-1)xd(-1)) or high (BMH or AMH, 8 mgxkg(-1)xd(-1)) dose of CsA from 1 week before or after STZ for 8 weeks. Diabetic rats without any treatment, insulin-treated diabetic rats and normal rats were also monitored simultaneously and served as control groups. The pathologic abnormalities of the aorta were verified by HE, Masson staining and electronmicroscopy. The depositions of immunoglobulins (IgG, IgM and IgA) were determined by immunohistochemistry and immunofluorescence methods., Results: At the end of study, lymphocytes infiltration and collagen content (26 582 +/- 6901) were significantly higher in diabetic aorta than those in non-diabetic aorta (Collagen: 7482 +/- 3491, P < 0.01). The deposited IgG and IgA were also significantly increased in diabetic aorta compared with non-diabetic aorta (IgG: 11 789 +/- 2491 vs. 2518 +/- 1066, P < 0.01; IgA: 17 430 +/- 3159 vs. 1135 +/- 758, P < 0.01). These changes were not affected by insulin while CsA intervention significantly reduced aortic collagen content (BMH: 13 518 +/- 5440, P < 0.01 vs. STZ) and immunoglobulin deposition (BMH: IgG: 7584 +/- 4462; IgA: 6176 +/- 1900, all P < 0.01 vs. STZ). These immunoglobulin deposition changes were confirmed by results of immunofluorescence. Aortic collagen accumulation was positively correlated to aortic immunoglobulin deposition (IgG, r = 0.556, P < 0.01; IgA, r = 0.661, P < 0.01)., Conclusions: Our data suggest that the autoimmune injuries might be a promoting factor in the pathogenesis of the diabetic macrovascular disease which could lead to the development of macrovascular disease. Immunosuppressive agent, such as CsA, could inhibit the abnormal deposition of immunoglobulins and therefore, delay the development of diabetic macrovascular disease in this model.

Objective: To study the autoimmune injuries on diabetic retinopathy (DR) and the protective effects of immunosuppressive therapy with cyclosporine A (CsA) on the DR of streptozotocin (STZ)-induced diabetic rats., Methods: STZ-induced diabetic rats were randomly divided into 3 groups: group 1: diabetic group without any treatment; group 2: insulin-treated group; group 3: CsA-treated group which was further divided into 2 subgroups: subgroup A: CsA was given 1 week before hyperglycemia appeared and subgroup B: CsA was given one week after hyperglycemia appeared. Subgroup A and subgroup B were further subdivided into 3 groups respectively, based on the dose of CsA (1, 4 and 8 mg x kg(-1) x d(-1)). As a control group, normal rats were also simultaneously monitored. The pathologic changes in the retina were investigated with HE stain and the deposition of immunoglobulins was detected with immunohistochemistry and immunofluorescent microscopy., Results: After 8 week, the deposition of IgG, IgA and IgM was quite significant in the retina of diabetic rats. The data also suggested that insulin treatment had no effects on the DR. In contrast,with CsA intervention, the deposition of immunoglobulins on the retina of diabetic rats vanished., Conclusions: Autoimmune injuries were shown, in the present study, to play a critical role in the pathogenesis of diabetic retinopathy. Immunosuppressive treatment with CsA showed protective effects by inhibiting the deposition of immunoglobulins in the retina of diabetic rats.