Dengue virus infection poses a growing public health and economic burden in a number of tropical and subtropical countries. Dengue circulates as a number of quasispecies, which can be divided by serology into four groups or serotypes. An interesting feature of Dengue, recognized over five decades ago, is that most severe cases that show hemorrhagic fever are not suffering from a primary infection. Instead, they are reinfected with a virus of different serotype. This observation poses considerable problems in vaccine design, and it is therefore imperative to gain a full understanding of the mechanisms underlying this immunological enhancement of disease. In this study, we examined a T cell epitope restricted by HLA-A*24, a major MHC class I allele, in Southeast Asia in a cohort of children admitted to a hospital with acute Dengue infection. The cytokine profiles and the degranulation capacity of T cells generated to this epitope are defined and compared across different viral serotypes. Cross-reactive Dengue-specific T cells seem to show suboptimal degranulation but high cytokine production, which may contribute to the development of the vascular leak characteristic of Dengue hemorrhagic fever.

The Thai Osteoporosis Foundation (TOPF) is an academic organization that consists of a multidisciplinary group of healthcare professionals managing osteoporosis. The first clinical practice guideline for diagnosing and managing osteoporosis in Thailand was published by the TOPF in 2010, then updated in 2016 and 2021. This paper presents important updates of the guideline for the diagnosis and management of osteoporosis in Thailand. A panel of experts in the field of osteoporosis was recruited by the TOPF to review and update the TOPF position statement from 2016. Evidence was searched using the MEDLINE database through PubMed. Primary writers submitted their first drafts, which were reviewed, discussed, and integrated into the final document. Recommendations are based on reviews of the clinical evidence and experts' opinions. The recommendations are classified using the Grading of Recommendations, Assessment, Development, and Evaluation classification system. The updated guideline comprises 90 recommendations divided into 12 main topics. This paper summarizes the recommendations focused on 4 main topics: the diagnosis and evaluation of osteoporosis, fracture risk assessment and indications for bone mineral density measurement, fracture risk categorization, management according to fracture risk, and pharmacological management of osteoporosis. This updated clinical practice guideline is a practical tool to assist healthcare professionals in diagnosing, evaluating, and managing osteoporosis in Thailand.

Human freeze-dried cancellous bone combined with human chondrocyte sheets have recently been used to construct an osteochondral-like tissue, which resembled a cartilage layer on a subchondral bone layer. Nevertheless, the efficacy of these human tissues in a xenogeneic model has been rarely reported. Therefore, this study aimed to evaluate the potential of human freeze-dried cancellous bones combined with human chondrocyte sheets for the treatment of osteochondral defects in rabbits. The key roles of the extracellular matrix (ECM) and released cytokines in these tissues in osteochondral repair were also assessed. Triple-layered chondrocyte sheets were constructed using a temperature-responsive culture surface. Then, they were placed onto cancellous bone to form chondrocyte sheet–cancellous bone tissues. The immunostaining of collagen type II (COL2) and the proteomic analysis of the human tissues were carried out before the transplantation. In our in vitro study, the triple-layered chondrocyte sheets adhered well on the cancellous bone, and the COL2 expression was apparent throughout the tissue structures. From the proteomic analysis results, it was found that the major function of the secreted proteins found in these tissues was protein binding. The distinct pathways were focal adhesion and the ECM–receptor interaction pathways. Among the highly expressed proteins, laminin-alpha 5 (LAMA5) and fibronectin (FN) not only played roles in the protein binding and ECM–receptor interaction, but also were involved in the cytokine-mediated signaling pathway. At 12 weeks after xenogeneic transplantation, compared to the control group, the defects treated with the chondrocyte sheets showed more hyaline-like cartilage tissue, as indicated by the abundance of safranin-O and COL2 with a partial collagen type I (COL1) expression. At 4, 8, and 12 weeks, compared to the defects treated with the cancellous bone, the staining of safranin-O and COL2 was more apparent in the defects treated with the chondrocyte sheet–cancellous bone tissues. Therefore, the human chondrocyte sheets and chondrocyte sheet–cancellous bone tissues provide a potential treatment for rabbit femoral condyle defect. LAMA5 and FN found in these human xenografts and their culture media might play key roles in the ECM–receptor interaction and might be involved in the cytokine-mediated signaling pathway during tissue repair.