Saikosaponin A (SSa) is isolated from the dried root of Radix Bupleuri , an herb widely used in traditional Chinese medicine, exerting antitumor activities. The T helper cell type 1(Th1)/Th2 balance is associated with antitumor immunity in breast cancer. The present study aimed to investigate the effects of SSa on Th1/Th2 balance in breast cancer and to explore the underlying mechanisms. Breast cancer in rats was induced by intragastrical administration of 7,12-dimethyl-benz[a] anthracene once (100 mg/kg). At d 91 , the rats suffering from tumors were randomly divided into three groups and treated with vehicle solution (control group), tamoxifen (TAM group), and SSa (SSa group) daily for 56 days, respectively. The tumor volume reduction ratio and tumor cell proliferation were detected to assess the antitumor effect of SSa. The positive staining numbers of CD8+ and CD4+ T cells infiltrated in breast tumors were measured by immunohistochemistry to evaluate the antitumor immunity of SSa. Cytokine levels in serum secreted by Th1 cells [interferon gamma (IFN-γ), interleukin (IL)-12] and Th2 cells (IL-4, IL-10) were detected to evaluate Th1/Th2 balance. The related molecules of IL-12/signal transducers and activators of transcription 4 (STAT4) pathway were detected by immunohistochemistry staining, RT-PCR, and Western blot to explore the mechanisms of SSa. The results showed that, compared with the control group, SSa significantly inhibited tumor growth and tumor cell proliferation. SSa enhanced antitumor immunity, which was demonstrated as increased CD8+ T cells and CD4+ T cells infiltrated in tumors. SSa shifted Th1/Th2 balance toward Th1, which was confirmed as increased serum IFN-γ and IL-12 levels, while decreased serum IL-4 and IL-10 levels. SSa increased IL-12, IL-12 receptor, and phosphorylated STAT4 expressions to promote Th1 differentiation. In conclusion, the present work suggested that SSa could inhibit breast cancer growth by shifting Th1/Th2 balance toward Th1. The underlying mechanism may involve activation of the IL-12/STAT4 pathway that induced Th1 differentiation.

It is very challenging to improve the catalytic activity of Pt-based catalysts since the strong CO chemisorption on Pt inhibits oxygen activation leading to poor activity at low temperature. Here, we report that introducing MO x (M = Fe, Co, Ni) to modify Pt catalysts (0.5 wt % Pt/CeO2) is a facile way to improve catalytic activity for CO oxidation at ambient temperature. The chemical state of Pt and the reducibility of doped MO x dominate the activity for CO oxidation. The electron-deficient Pt due to the strong interaction between Pt and MO x leads to the weaker CO adsorption strength. Meanwhile, the higher reducibility of FeO x and CoO x extends the reaction routine due to the improved activity of oxygen with the help of the redox cycle between FeO x /CoO x and CeO2. However, the stability of catalyst depends on the ability to recover consumed oxygen, and the reversible compensation of consumed oxygen species makes CoO x /Pt/CeO2 and NiO x /Pt/CeO2 remain stable with time on stream. Our study shows that CoO x is a potential candidate to increase Pt atom efficiency for CO oxidation on Pt/CeO2 catalysts.

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Widely distributed in southern China, the windmill palm tree (Trachycarpus fortunei) is an important economic tree species from which palm fiber can be stripped. Palm Fiber (PF) is divided into palm leaf sheath fiber (PLSF) and palm petioles fiber (PPF), and both have good elasticity. These fibers can be used to produce mattresses and other elastic compound materials. While PLSF and PPF shared a similar elastic modulus, the elastic limit and elastic strain of PLSF were found to be significantly higher than that of PPF. Also, PLSF had superior tensile elastic properties. Within the elastic range, the bending and tensile properties of PF were almost the same. When given force under the horizonal-straight state, PLSF displayed superior bending elastic properties.

Dermatomyositis (DM) is a severe autoimmune disease of the connective tissue characterized by inflammatory and degenerative changes in the skin and muscle. However, the lack of experimental models of DM represents a challenge for the development of effective drugs. The aim of the present study was to establish a pharmacodynamic rat model of DM that would recapitulate the clinical manifestation seen in patients. The DM model was established using membrane antigen-induced autoimmune injury, followed by toxin-induced subcutaneous calciphylaxis. The rats were divided into five groups and were subcutaneously injected with membrane antigen. Of these, four antigen-immunized groups then received dihydrotestosterone (DHT), iron-dextrin (Fe-Dex), polymyxin (PMX) either individually or in combination to induce cutaneous calciphylaxis. The clinical manifestation score, ratio of infiltrated lymphocytes, ratio of arteriole calcified nodules in skeletal muscles, serum antibody levels [anti-histidyl tRNA synthetase (Jo-1) and anti-melanoma differentiation-associated protein 5 (MDA5)] and serum cytokine levels [tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ)] were then detected. The results demonstrated that all five autoimmune groups displayed local cutaneous swelling and weakness, increased serum antibody and cytokine levels, and T lymphocyte infiltration in perimysial and perivascular sites. Moreover, pathological changes indicative of calciphylaxis were observed in the PMX and DHT + Fe-Dex + PMX. Among all groups, the rats in the PMX and DHT + Fe-Dex + PMX displayed characteristics most closely resembling those of DM pathogenesis in patients. In conclusion, membrane antigen immunization combined with toxin-induced calciphylaxis can be used as a DM model in rats. This model may be used for the development of effective drugs for DM treatment.

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