These results suggest that PDT with EDTA-2Na and ALA is a potential novel treatment option for PA-infected wounds.

Signal transducer and activator of transcription 3 (STAT3) is involved in many biological processes, including immunity and cancer. STAT3 becomes phosphorylated at Tyr705 and Ser727 on IL-6 stimulation. Phospho-Tyr705 (pY705) stabilizes the STAT3 dimer with reciprocal interactions between pY705 and the SH2 of the other molecule and phospho-Ser727 (pS727) accelerates pY705 dephosphorylation. We study how pS727 regulates STAT3 in both structural and biological perspectives. Using STAT3 reconstituted in HepG2-stat3-knockout cells, we show that pS727, together with a handshake N-terminal domain (NTD) interaction, causes rapid inactivation of STAT3 for pY705 dephosphorylation and a chromosome region maintenance 1 (CRM1)-independent nuclear export, which is critical for faithful STAT3 response to the cellular signals. The various N-terminal tags, GFP-related Ruby and FLAG, rendered the export CRM1-dependent and especially FLAG-tag caused nuclear accumulation of STAT3, indicating the presence of conformational changes in inactivation. Impaired reactivation of STAT3 by S727A or FLAG-tag delayed or inhibited the IL-6-induced saa1 mRNA expression, respectively. The detailed analysis of the pY705–SH2 structure identified the C-terminal tail (CTT) from L706 to P715 as a key regulator of the CTT–CTT intermolecular and the CTT–SH2 intramolecular interactions that support pY705–SH2 association. The functional studies using multiple STAT3 mutants indicated that the degree of the two interactions determines the stability of pY705–SH2 interaction. Importantly, Pro715 was critical for the pS727's destabilizing activity and the known phosphorylation and acetylation at the CTT structurally inhibited the pY705–SH2 interaction. Thus, pS727 triggers pY705–SH2 dissociation by weakening the supportive interactions likely through CTT modulation, inducing rapid cycles of STAT3 activation–inactivation for proper function of STAT3.

Although long noncoding RNAs (lncRNAs) are transcripts that do not encode proteins by definition, some lncRNAs actually contain small open reading frames that are translated. TINCR (terminal differentiation–induced ncRNA) has been recognized as a lncRNA that contributes to keratinocyte differentiation. However, we here show that TINCR encodes a ubiquitin-like protein that is well conserved among species and whose expression was confirmed by the generation of mice harboring a FLAG epitope tag sequence in the endogenous open reading frame as well as by targeted proteomics. Forced expression of this protein promoted cell cycle progression in normal human epidermal keratinocytes, and mice lacking this protein manifested a delay in skin wound healing associated with attenuated cell cycle progression in keratinocytes. We termed this protein TINCR-encoded ubiquitin-like protein (TUBL), and our results reveal a role for TINCR in the regulation of keratinocyte proliferation and skin regeneration that is dependent on TUBL.

Pigmentation in the dermis is known to be caused by melanophages, defined as melanosome-laden macrophages. In this study, we show that dermal fibroblasts also have an ability to uptake melanosomes and apoptotic melanocytes. We have previously demonstrated that normal human melanocytes constantly secrete melanosome clusters from various sites of their dendrites. After adding secreted melanosome clusters collected from the culture medium of melanocytes, time-lapse imaging showed that fibroblasts actively attached to the secreted melanosome clusters and incorporated them. Annexin V staining revealed that phosphatidylserine (PtdSer), which is known as an ‘eat-me’ signal that triggers the internalization of apoptotic cells by macrophages, is exposed on the surface of secreted melanosome clusters. Dermal fibroblasts were able to uptake secreted melanosome clusters as did macrophages, and those fibroblasts express TIM4, a receptor for PtdSer-mediated endocytosis. Further, co-cultures of fibroblasts and melanocytes demonstrated that dermal fibroblasts internalize PtdSer-exposed apoptotic melanocytes. These results suggest that not only macrophages, but also dermal fibroblasts contribute to the collection of potentially toxic substances in the dermis, such as secreted melanosome clusters and apoptotic melanocytes, that have been occasionally observed to drop down into the dermis from the epidermis.

Cytotoxic effects of ethanol on cultured human hepatocytes and fibroblasts differed with the type of culture medium used. When cytotoxic effects of ethanol were compared between culture systems using either RPMI-1640 or Dulbecco's modified Eagle's medium (DMEM), the cytotoxicity was more prominent with the former medium than with the latter. A reduction of the cytotoxic effects appeared to be due to the pyruvate contained in DMEM. The protective effect of pyruvate against ethanol toxicity may be related to tricarboxylic acid (TCA) cycle activity because addition of malate to the medium also reduced the cytotoxic effects. Our results suggest that drug cytotoxicity testing in vitro must be done using various types of culture medium.

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Recently, bacteria resistant to many antibiotics have spread and become a problem. Because using antibiotic causes to produce antibiotic-resistant bacteria, it is thought that it is necessary to develop new mean which is different from antibiotic, in order not to increase the number of resistant bacteria anymore. We focus on and study photodynamic therapy (PDT) as new treatment of bacteria infections. Here, we report effect of PDT against infection ulcer we have done so far. Key words： photodynamic therapy (PDT), 5-aminolevulinic acid (ALA), methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa

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