Prolonged Activation of ERK Contributes to the Photorejuvenation Effect in Photodynamic Therapy in Human Dermal Fibroblasts

Photodynamic therapy (PDT) is known to be effective in the photorejuvenation of photoaged skin. However, the molecular mechanisms of rejuvenation by PDT remain elusive. In this study, we aimed to understand the molecular events occurring during the photorejuvenation after PDT in dermal fibroblasts in vitro. First, we found that PDT conditions resulted in an increased fibroblast proliferation and motility in vitro. Under this condition, cells had increased intracellular reactive oxygen species (ROS) production. Importantly, PDT induced a prolonged activation of extracellular signal–regulated kinase (ERK) with a corresponding increase in matrix metalloproteinase (MMP)-3 and collagen type Iα messenger RNA and protein. Moreover, inhibition of PDT-induced ERK activation significantly suppressed fibroblast proliferation and expression of MMP-3 and collagen type Iα following PDT. In addition, NAC (an antioxidant) inhibited PDT-induced fibroblast proliferation and ERK activation indicating that prolonged ERK activation and intracellular ROS contribute to the proliferation of fibroblasts and the dermal remodeling process for skin rejuvenation. We also identified increased collagen volume and decreased elastotic materials that are used as markers of photoaging in human skin samples using histochemical studies. Results from this study suggest that intracellular ROS stimulated by PDT in dermal fibroblasts lead to prolonged activation of ERK and, eventually, fibroblast proliferation and activation. Our data thus reveal a molecular mechanism underlying the skin rejuvenation effect of PDT

A Case of Birt-Hogg-Dubé Syndrome

Birt-Hogg-Dubé syndrome (BHDS) is an autosomal dominant genodermatosis characterized by cutaneous hair follicle tumors (fibrofolliculoma or trichodiscoma), pulmonary cysts, and increased risk of renal neoplasia. The genetic alteration for BHDS has been mapped to chromosome 17p12q11, and the gene in this region has been cloned and believed to be responsible for the BHDS. Mutations in the BHD gene (also known as FLCN) have been described in the patients with BHDS. We present a case of a 30-yr-old Korean woman with multiple mildly pruritic papules on her face and neck area. The patient had several firm, flesh-colored, dome-shaped, papular lesions measuring between 2 to 5 mm. Except for a history of pneumothorax her medical records were not remarkable. Mutation analysis of the BHD gene was performed, and a novel deletion mutation (p.F519LfsX17 [c.1557delT]) causing truncation of the gene product, folliculin, was found in the exon 14. The actual incidence of BHDS is unknown, but it is most likely underdiagnosed. So it is imperative that doctors recognize the skin lesions of BHDS and institute proper screening to detect other manifestations of the disease. Here, we report a case of BHDS with a novel mutation, which is the first report in Korea

Export of recombinant proteins in Escherichia coli using ABC transporter with an attached lipase ABC transporter recognition domain (LARD)

<p>Abstract</p> <p>Background</p> <p>ATP binding cassette (ABC) transporter secretes the protein through inner and outer membranes simultaneously in gram negative bacteria. Thermostable lipase (TliA) of <it>Pseudomonas fluorescens </it>SIK W1 is secreted through the ABC transporter. TliA has four glycine-rich repeats (GGXGXD) in its C-terminus, which appear in many ABC transporter-secreted proteins. From a homology model of TliA derived from the structure of <it>P. aeruginosa </it>alkaline protease (AprA), lipase ABC transporter domains (LARDs) were designed for the secretion of fusion proteins.</p> <p>Results</p> <p>The LARDs included four glycine-rich repeats comprising a β-roll structure, and were added to the C-terminus of test proteins. Either Pro-Gly linker or Factor Xa site was added between fusion proteins and LARDs. We attached different length of LARDs such as LARD0, LARD1 or whole TliA (the longest LARD) to three types of proteins; green fluorescent protein (GFP), epidermal growth factor (EGF) and cytoplasmic transduction peptide (CTP). These fusion proteins were expressed in <it>Escherichia coli </it>together with ABC transporter of either <it>P. fluorescens </it>or <it>Erwinia chrysanthemi</it>. Export of fusion proteins with the whole TliA through the ABC transporter was evident on the basis of lipase enzymatic activity. Upon supplementation of <it>E. coli </it>with ABC transporter, GFP-LARDs and EGF-LARDs were excreted into the culture supernatant.</p> <p>Conclusion</p> <p>The LARDs or whole TliA were attached to C-termini of model proteins and enabled the export of the model proteins such as GFP and EGF in <it>E. coli </it>supplemented with ABC transporter. These results open the possibility for the extracellular production of recombinant proteins in <it>Pseudomonas </it>using LARDs or TliA as a C-terminal signal sequence.</p

Development of Dermatomyofibroma in a Male Infant

Dermatomyofibroma is a rare benign cutaneous mesenchymal neoplasm of the fibroblasts and myofibroblasts. The majority of dermatomyofibromas present as red-brown discolored plaques or nodules, commonly located on the shoulder, upper arm, axilla, neck, and/or upper trunk. These lesions develop most frequently in young female patients at a mean of 28-years-of-age. Herein, a case of dermatomyofibroma is reported that developed in an infant. A 4-month-old boy presented with an ill-defined bluish firm plaque on the trunk that developed 1 month after birth. Histopathologically, there was proliferation of bland-looking spindle cells with fascicular arrangement in the dermis and subcutaneous tissue. Immunohistochemistry showed that most of the tumor cells expressed diffuse positivity for vimentin and smooth muscle actin, but were negative for S-100 protein, desmin, and CD34

Comparison of Characteristics of Acquired Bilateral Nevus of Ota-like Macules and Nevus of Ota According to Therapeutic Outcome

Both acquired bilateral nevus of Ota-like macules (ABNOM) and nevus of Ota are characterized by the presence of dermal melanocytes. There are no differences in the method of treatment, however, postinflammatory hyperpigmentation (PIH) develops more often in ABNOM than in nevus of Ota following treatment. We investigated the differences in the development of PIH after treatment between ABNOM and nevus of Ota, and the histopathologic differences in the PIH. A total of 82 patients with ABNOM (n=47) and nevus of Ota (n=35) were treated with Q-switched alexandrite laser and followed up 2 weeks and 3 months later. Biopsies were performed on lesional skin before treatment. The distribution and the amount of melanin pigments were visualized with Fontana-Masson stain, and the distribution and the depth of melanocytes were measured by GP-100 (NK1-beteb) stain. Clinically, there was more erythema and PIH in ABNOM than in nevus of Ota. Histopathologically, intradermal melanocytes were clustered in groups and dispersed perivascularly in ABNOM, while melanocytes were scattered evenly throughout the dermis in nevus of Ota. Both groups show that when there is a statistically significant number of melanocytes in the perivascular area, erythema and PIH occur after laser therapy. In conclusion, indirect vessel injury in addition to perivascular clustering melanocytes might be considered the cause of increased PIH after treatment in ABNOM

Clear Cell Basal Cell Carcinoma with Sialomucin Deposition

Clear cell basal cell carcinoma (BCC) is a variant of BCC with a characteristic clear cell component that may occupy all or part of the tumor islands. Periodic acid-Schiff (PAS) staining for glycogen is variably positive, and mild deposition of sulfated mucin has been noted. However, to our knowledge, clear cell BCC with sialomucin deposition has not been reported. Here we report a case of clear cell BCC showing sialomucin deposition. The clear tumor cells stained with PAS and showed incomplete diastase-resistance. In addition, mucin staining with alcian blue was positive at pH 2.5 but not at pH 0.5

Congenital Atrophoderma of Pasini and Pierini

Idiopathic atrophoderma of Pasini and Pierini is a form of dermal atrophy of unknown etiology, usually affecting women during their adolescence and young adulthood. A 2-yr-old girl was presented with erythematous atrophic lesion on the right shoulder, which appeared from birth. The histologic findings were consistent with atrophoderma. This patient, to the best of our knowledge, is the first case of atrophoderma with an onset since birth