Objective To observe the effect and mechanism of imiquimod on T helper (Th) cell subsets in the Parabronchial lymph node (PBLN) cell cultures from ovalbumin (OVA)-sensitized rats.Methods PBLN were isolated and cultured. PBLN cells were divided into A~F, according to different concentrations of intervention. Cultured for 0, 3, 6, 12, 24, 48 hours, the expressions of IL-4 and IFN-? in supernatants were determined by ELISA. The mRNA expressions of the cytokines in cells were detected by RT-PCR.Results In the group A, only low concentrations of IFN-? were detected. Based on the cultured time, the concentrations of IFN-? were increased significantly if imiquimod concentration was between 1 and 10 ?g/ml. Levels of IL-4 were increased slowly compared with those in the group B (P0.05).Conclusion Imiquimod show the best effect on antigen-specific Th cell subsets when cultured for 12h. The results suggest that imiquimod have benefit in atopic diseases such as the late inflammation reaction of asthma.

With the rapid acceleration of aging in China, there is a huge need for elderly patients to have improved quality of life in the terminal stage.Palliative sedation is an integral part of palliative care and can alleviate painful refractory symptoms, and its use in patients in various terminal illnesses is being explored across the world.Attention is focused on its indications and implementation.In China, palliative sedation in clinical practice is in an early exploratory stage and relevant criteria and guidelines have yet to be established.A review of the current practice and research progress concerning palliative sedation for patients' end-of-life care in China and the rest of the world will offer insight and strategic considerations in the initial pursuit and accelerated acceptance in the future in China.