Sita Virakul

Chulalongkorn University · Department of Microbiology

Graves’ ophthalmopathy (GO) is an extra-thyroidal complication of Graves’ disease which can lead to vision loss in severe cases. Currently, treatments of GO are not sufficiently effective, so novel therapeutic strategies are needed. As platelet-derived growth factor (PDGF)-BB induces several effector mechanisms in GO orbital fibroblasts including c...

Human neutrophil peptides (HNPs) can induce cell proliferation and activation so their growth promoting activities may have potential clinical benefit. This study investigated the effects of HNPs on human dermal fibroblasts. Differential gene expression in HNP-treated cells and genes involved in regulating intracellular pathways were explored. Derm...

Host defense peptides (HDPs) or antimicrobial peptides (AMPs) are short cationic amphipathic peptides of divergent sequences, which are part of the innate immune system and produced by various types of cells and tissues. The predominant role of HDPs is to respond to and protect humans against infection and inflammation. Common human HDPs include de...

Background: Graves' ophthalmopathy (GO) is an autoimmune eye disease with the characteristic symptoms of eyelid retraction and proptosis. Orbital fibroblast activation induced by PDGF-BB stimulation plays a crucial role in GO pathogenesis, leading to excessive proliferation and extracellular matrix production by orbital fibroblasts. Currently, GO...

Background Graves’ ophthalmopathy (GO) is a frequent extrathyroidal complication of Graves’ hyperthyroidism. Orbital fibroblasts contribute to both orbital tissue inflammation and remodeling in GO, and as such are crucial cellular elements in active GO and inactive GO. However, so far it is largely unknown whether GO disease progression is associat...

Aspergillus flavus is one of the most common isolates from patients with fungal infections. Aspergillus infection is usually treated with antifungal agents, but side effects of these agents are common. Trehalase is an essential enzyme involved in fungal metabolism, and the trehalase inhibitor, validamycin A, has been used to prevent fungal infectio...

Candida glabrata is a common non-albicans Candida species found in patients with candidiasis and it sometimes develops antifungal resistance. Human beta-defensin-3 (hBD-3) is an antimicrobial peptide of immune system active against various types of microbes including Candida spp. This study investigated antifungal activity of hBD-3 and its synergis...

Background: Basic fibroblast growth factor (bFGF) has been implicated in the pathogenesis of Graves' orbitopathy (GO). It stimulates several processes, including hyaluronan synthesis, involved in orbital tissue volume expansion and may act synergistically with platelet-derived growth factor (PDGF)-BB. PDGF-BB is known to stimulate adipogenesis in...

Mast cells and their products are likely to be involved in regulating orbital fibroblast activity in Graves' Ophthalmopathy (GO). Histamine is abundantly present in granules of mast cells and is released upon mast cell activation. However, the effect of histamine on orbital fibroblasts has not been examined so far. Orbital tissues from GO patients...

Graves' ophthalmopathy (GO) is an extra-thyroidal complication of Graves' disease (GD; Graves' hyperthyroidism) characterized by orbital tissue inflammation, expansion, remodeling and fibrosis. Although the initiating trigger of GO is still indistinct, excessive orbital fibroblast activity is at the heart of its pathogenesis. Orbital fibroblasts ar...

Platelet-derived growth factor (PDGF)-BB has been identified as important factor in pathogenesis of Graves' ophthalmopathy (GO). It stimulates proliferation, cytokine, and hyaluronan production, and thyrotropin receptor expression by orbital fibroblasts. Therefore, the PDGF-pathway has been proposed as a target for pharmacological intervention in G...

Activation of orbital fibroblasts resulting in excessive proliferation, cytokine and hyaluronan production and differentiation into adipocytes, is a main determinant of orbital tissue inflammation and tissue expansion in Graves' ophthalmopathy (GO). During the last years we have shown that the platelet-derived growth factor (PDGF) isoforms PDGF-AA,...

Background: Graves' ophthalmopathy (GO) remains hard to treat. Excessive orbital fibroblast activation by platelet-derived growth factor (PDGF)-BB contributes to GO. The tyrosine kinase inhibitors (TKIs) imatinib mesylate and dasatinib both target PDGF-receptor tyrosine kinase activity, albeit with a different potency. We compared the efficacy of...

In this study, we reported a new technique in detecting HLA-B*15:02 by using a nested sequence-specific primer-polymerase chain reaction (SSP-PCR) that can be used on genomic DNA and whole blood for carbamazepine hypersensitivity prediction. We tested a total of 200 blind samples with known human leukocyte antigen (HLA)-B allelic types (44 positive...