In vivo effects of fluconazole on lymphocyte subpopulations of the thymus and spleen in mice: flow cytometry analysis

Methods and Advances in the Design, Testing and Development of In Vitro Diagnostic Instruments

With the continuous improvement of medical testing and instrumentation engineering technologies, the design, testing and development methods of in vitro diagnostic instruments are developing rapidly. In vitro diagnostic instruments are also gradually developing into a class of typical high-end medical equipment. The design of in vitro diagnostic instruments involves a variety of medical diagnostic methods and biochemical, physical and other related technologies, and its development process involves complex system engineering. This paper systematically organizes and summarizes the design, testing and development methods of in vitro diagnostic instruments and their development in recent years, focusing on summarizing the related technologies and core aspects of the R&D process, and analyzes the development trend of the in vitro diagnostic instrument market.

Design and Synthesis of Biotinylated Bivalent Carboline Derivatives as Potent Antitumor Agents

Compound 6, a novel β-carboline comprising two 1-methyl-9H-β-carboline-3-carboxylic acids and a biotin moiety conjugated together using tris(2-aminoethyl)amine, was synthesized and tested for its cytotoxicity toward MCF-7 and HepG2 cell lines and antitumor potency in an S180 tumor-bearing mouse model. Compound 6 was delivered via biotin receptor-mediated endocytosis and exerted its therapeutic effects by intercalation binding with DNA. In vivo antitumor evaluations of 6 revealed that it is efficacious and exhibits low systemic toxicity.

Comparison of worm development and host immune responses in natural hosts of Schistosoma japonicum, yellow cattle and water buffalo

BACKGROUND

Yellow cattle and water buffalo are two of the most important natural hosts for Schistosoma japonicum in China. Previous observation has revealed that yellow cattle are more suited to the development of S. japonicum than water buffalo. Understanding more about the molecular mechanisms involved in worm development, as well as the pathological and immunological differences between yellow cattle and water buffalo post infection with S japonicum will provide useful information for the vaccine design and its delivery procedure.

RESULTS

The worm length (p < 0.01), worm recovery rate (p < 0.01) and the percentage of paired worms (p < 0.01) were significantly greater in yellow cattle than those in water buffalo. There were many white egg granulomas in the livers of yellow cattle, but fewer were observed in water buffalo at 7 weeks post infection. The livers of infected yellow cattle contained significantly increased accumulation of inflammatory cells, and the schistosome eggs were surrounded with large amounts of eosinophil infiltration. In contrast, no hepatocyte swelling or lymphocyte infiltration, and fewer white blood cells, was observed in water buffalo. The percentage of CD4⁺ T cells was higher in yellow cattle, while the percentage of CD8⁺ T cells was higher in water buffalo from pre-infection to 7 w post infection. The CD4/CD8 ratios were decreased in both species after challenge with schistosomes. Comparing with water buffalo, the IFN-γ level was higher and decreased significantly, while the IL-4 level was lower and increased gradually in yellow cattle from pre-infection to 7 w post infection.

CONCLUSIONS

In this study, we confirmed that yellow cattle were more suited to the development of S. japonicum than water buffalo, and more serious pathological damage was observed in infected yellow cattle. Immunological analysis suggested that CD4⁺ T cells might be an integral component of the immune response and might associate with worm development in yellow cattle. A shift from Th1 to Th2 type polarized immunity was only shown clearly in schistosome-infected yellow cattle, but no shift in water buffalo. The results provide valuable information for increased understanding of host-schistosome interactions, and for control of schistosomiasis.

{2-[1-(3-Methoxycarbonylmethyl-1H-indol-2-yl)-1-methyl-ethyl]-1H-indol-3-yl}-acetic acid methyl ester (MIAM): its anti-cancer efficacy and intercalation mechanism identified via multi-model systems

{2-[1-(3-Methoxycarbonylmethyl-1H-indol-2-yl)-1-methyl-ethyl]-1H-indol-3-yl}-acetic acid methyl ester (MIAM) was provided as a DNA-intercalator. For the comprehensive evaluation of this new intercalator, an assay system consisting of cell, S180 mouse, healthy mouse, spectrum, non-spectrum, and gel electrophoresis models was constructed. On the cell (S180, K562, MCF-7, HeLa and HepG2) models, MIAM selectively inhibited the viability of HeLa. On the S180 mouse model, 0.89, 8.9, 89 and 890 μmol kg(-1) of MIAM dose-dependently inhibited the tumor growth. Even at a dose of 890 μmol kg(-1), MIAM did not damage the treated S180 mice. The safety of MIAM was supported by a high spleen index and an obvious increase of body weight of the treated S180 mice. On the healthy mouse model the LD(50) value of MIAM is higher than 890 μmol kg(-1). The ultraviolet (UV), fluorescence, circular dichroism (CD), relative viscosity, melting curve, and gel electrophoresis assays of DNA with or without MIAM consistently supported an intercalation mechanism for MIAM.

Study on differences in the pathology, T cell subsets and gene expression in susceptible and non-susceptible hosts infected with Schistosoma japonicum

More than 40 kinds of mammals in China are known to be naturally infected with Schistosoma japonicum (S. japonicum); Microtus fortis (M. fortis), a species of vole, is the only mammal in which the schistosomes cannot mature or cause significant pathogenic changes. In the current study, we compared the differences in pathology by Hematoxylin-eosin staining and in changes in the T cell subsets with flow cytometry as well as gene expression using genome oligonucleotide microarrays in the lung and liver, before challenge and 10 days post-infection with schistosomes in a S. japonicum-susceptible mouse model of infection, a non-susceptible rat model and the non-permissive host, M. fortis. The results demonstrated that S. japonicum promoted a more intensive immune response and more pathological lesions in M. fortis and rats than in mice. Hematoxylin-eosin staining revealed that the immune effector cells involved were mainly eosinophilic granulocytes supplemented with heterophilic granulocytes and macrophages. The analysis of splenic T cell subsets showed that CD4(+) T cell subsets and the CD4(+)/CD8(+) ratio were increased, while the CD8(+) T cell subsets decreased remarkably in rats; whereas the CD8(+) T cell subsets were increased, but the CD4(+)/CD8(+) ratio was decreased significantly in mice. The analysis of the pattern of gene expression suggested that some immune-associated genes and apoptosis-inducing genes up-regulated, while some development-associated genes were down-regulated in the infected M. fortis compared to the uninfected controls; the three different hosts have different response mechanisms to schistosome infection. The results of this study will be helpful for identifying the key molecules in the immune response to S. japonicum in M. fortis and for understanding more about the underlying mechanism of the response, as well as for elucidating the interaction between S. japonicum and its hosts.