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Dive into the research topics where Akihiko Fujisawa is active.

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Featured researches published by Akihiko Fujisawa.


British Journal of Dermatology | 2011

microRNA-mediated keratinocyte hyperproliferation in psoriasis vulgaris

Asako Ichihara; Masatoshi Jinnin; Keitaro Yamane; Akihiko Fujisawa; Keisuke Sakai; Shinichi Masuguchi; Satoshi Fukushima; Keishi Maruo; Hironobu Ihn

Background  Psoriasis is a chronic inflammatory skin disease characterized by intense proliferation and abnormal differentiation of keratinocytes, although the pathogenesis is still not completely clarified.


British Journal of Dermatology | 2009

Basic fibroblast growth factor stimulates the proliferation of human dermal fibroblasts via the ERK1/2 and JNK pathways.

Takamitsu Makino; Masatoshi Jinnin; Faith C. Muchemwa; Satoshi Fukushima; H. Kogushi‐Nishi; Chikako Moriya; Toshikatsu Igata; Akihiko Fujisawa; Takamitsu Johno; Hironobu Ihn

Background  Basic fibroblast growth factor (bFGF, FGF‐2) has been described as a multipotent cytokine that regulates cell growth as well as differentiation, matrix composition, chemotaxis, cell adhesion and migration in numerous cell types. It is known that bFGF stimulates proliferation of cultured fibroblasts. However, the detailed mechanism of fibroblast proliferation induced by bFGF in vitro still remains to be elucidated.


European Journal of Dermatology | 2013

Detection of hair root miR-19a as a novel diagnostic marker for psoriasis

Hiroki Hirao; Masatoshi Jinnin; Asako Ichihara; Akihiko Fujisawa; Katsunari Makino; Ikko Kajihara; Keisuke Sakai; Satoshi Fukushima; Yuji Inoue; Hironobu Ihn

BACKGROUND Objective biomarkers that reflect the diagnosis and disease activity have not been in clinical use for psoriasis. OBJECTIVES We investigated the hair root miR-19a levels, regulatory microRNA of TNF-α, and evaluated the possibility that miR-19a can be a biomarker of psoriasis. MATERIALS AND METHODS microRNAs were extracted from hair roots of patients with psoriasis (n = 18) and healthy controls (n = 22). Samples from 10 atopic dermatitis patients and 4 dermatomyositis patients were also included as the disease controls. miR-19a levels were determined by quantitative real-time PCR. RESULTS Hair root levels of miR-19a were significantly up-regulated only in psoriasis compared with normal controls. In characteristics (ROC) curve analysis for hair root miR-19a, to distinguish psoriasis patients from normal subjects, the areas under curve (AUC) was 0.87. Relative miR-19a levels were inversely and significantly correlated with duration between symptom onset and the first visit to the hospital in psoriasis patients. CONCLUSIONS Our results indicated hair root miR-19a levels are effective as a disease marker.


Journal of The Optical Society of America B-optical Physics | 2010

Interference between electromagnetically induced transparency and two-step excitation in three-level ladder systems

Nobuhito Hayashi; Akihiko Fujisawa; Hiroaki Kido; Ken Ichi Takahashi; Masaharu Mitsunaga

We have performed electromagnetically induced transparency (EIT) and two-photon absorption experiments in ladder-type three-level systems in a hot sodium atomic vapor, using the 3S1/2-3P1/2-4D3/2, 3S1/2-3P3/2-4D3/2,5/2, 3S1/2-3P1/2-5S1/2, and 3S1/2-3P3/2-5S1/2 transitions. In particular, in the most pronounced 3S1/2-3P1/2-4D3/2 system, we have observed quite unique spectral line shapes that are superpositions of sharp dips and peaks, in contrast to ordinary EIT spectra. The peaks and dips have apparently different physical origins, and the line shape can be interpreted as the interference between EIT and two-step excitation.


Journal of Dermatology | 2014

miR-424 levels in hair shaft are increased in psoriatic patients

Yasuo Tsuru; Masatoshi Jinnin; Asako Ichihara; Akihiko Fujisawa; Chikako Moriya; Keisuke Sakai; Satoshi Fukushima; Hironobu Ihn

Objective diagnostic markers have not been in clinical use for psoriasis. In this study, we investigated the levels of miR‐424 in hair roots and hair shafts in psoriatic patients, and evaluated the possibility that miR‐424 can be a biomarker of the disease. A single hair root and five pieces of hair shafts (~5 cm in length) were obtained from the non‐lesional occiput of each individual of 26 psoriatic patients. Control hair samples were collected from nine normal subjects. Samples from 10 atopic dermatitis patients were also included as the disease control. miR‐424 levels were determined by quantitative real‐time polymerase chain reaction. Hair shaft miR‐424 levels were significantly upregulated only in patients with psoriasis compared with normal controls and those with atopic dermatitis. By receiver–operator curve analysis of hair shaft miR‐424 to distinguish psoriatic patients from normal subjects, the area under the curve was 0.77. However, relative miR‐424 levels were not correlated with disease activity markers including disease duration, body surface area and Psoriasis Area and Severity Index. Hair root miR‐424 was not useful for evaluating both diagnosis and severity of the disease. Our results indicated hair shaft miR‐424 levels may be useful as a diagnostic marker of psoriasis.


Journal of Dermatological Science | 2014

Analysis of expression pattern of serum microRNA levels in patients with psoriasis

Yusaku Koga; Masatoshi Jinnin; Asako Ichihara; Akihiko Fujisawa; Chikako Moriya; Keisuke Sakai; Satoshi Fukushima; Yuji Inoue; Hironobu Ihn

alysis of expression pattern of serum icroRNA levels in patients with psoriasis seen only in miR-125b levels between normal subjects and AD patients (P = 0.0032). When receiver operating characteristics (ROC) curves of all 6 miRNA levels were analyzed, the serum levels of miR-203, miRNA which is most significantly downregulated in PV patients as described above, might serve as more useful biomarker for differentiating PV patients and normal subjects with the areas under curves (AUCs) of 0.92 than levels of other 5 miRNAs (Fig. S1): according to the Youden index, the most optical ywords: ammatory skin diseases; Epigenetics; croRNA


Optics Letters | 2009

Parametric oscillation in sodium vapor by using an external cavity

Junji Okuma; Nobuhito Hayashi; Akihiko Fujisawa; Masaharu Mitsunaga; Ken Ichi Harada

We report on parametric oscillation in sodium atomic vapor by using an external cavity. Output powers of approximately 56 mW are obtained for both the signal and idler waves with the input coupling power of 290 mW, resulting in a conversion efficiency of 39%. The signal and idler frequencies are either upshifted or downshifted from the coupling frequency by the amount of the Na hyperfine splitting frequency, and the two waves are found to be strongly temporally correlated.


Optics Letters | 2009

Ultraslow matched-pulse propagation in sodium vapor

Junji Okuma; Nobuhito Hayashi; Akihiko Fujisawa; Masaharu Mitsunaga

We have observed ultraslow propagation of matched pulses in a parametric amplifying hot sodium vapor. A fractional delay of more than 1 and a gain of 28 have been simultaneously achieved for a probe pulse of width 100 ns, accompanying a conjugate Stokes pulse with similar gain and delay under a strong coupling beam. The results are compared with the preceding work by Boyer et al. [Phys. Rev. Lett. 99, 143601 (2007)].


Journal of Dermatology | 2014

Case of pemphigoid vegetans positive with both BP180 and BP230 in enzyme-linked immunosorbent assays.

Eiko Nagamoto; Akihiko Fujisawa; Masatoshi Jinnin; Hiroshi Koga; Norito Ishii; Takashi Hashimoto; Yuichiro Yoshino

Naoko TAKAYAMA, Sonoko NAKAZONO, Jiro KUMAGAI, Takahiro KAWAMURA, Fumihito SUZUKI, Norito ISHII, Takashi HASHIMOTO, Takeshi NAMIKI Departments of Dermatology, Pathology, Gastroenterology, Rheumatology, Yokohama City Minato Red Cross Hospital, Naka-ku, Yokohama and Department of Dermatology, Kurume University School of Medicine, Kurume University Institute of Cutaneous Cell Biology, Kurume, Fukuoka, Japan


Annals of Dermatology | 2014

Clinical significance of serum vascular endothelial-cadherin levels in inflammatory skin diseases.

Haruka Kuriyama; Masatoshi Jinnin; Hisashi Kanemaru; Asako Ichihara; Akihiko Fujisawa; Chikako Moriya; Satoshi Fukushima; Hironobu Ihn

Dear Editor: Inflammatory skin diseases are sometimes accompanied by vascular abnormalities; e.g. Auspitz phenomenon in psoriasis or white dermographism in atopic dermatitis (AD)1,2. However, the detailed mechanism(s) and role of such vasculopathy in the pathogenesis of each disease are still unclear. Vascular endothelial (VE)-cadherin is one of the major components of adherens junctions between endothelial cells. The critical role of VE-cadherin is vascular morphogenesis during embryogenesis. Such function of VE-cadherin is regulated by vascular endothelial cell growth factor (VEGF) signaling through the VEGF receptor leads to the increased detachment of endothelial cells and transendothelial permeability by promoting VE-cadherin internalization3. On the other hand, VE-cadherin limits the proliferation of endothelial cells by preventing the internalization of the VEGF receptor4. However, the role of VE-cadherin in the vascular abnormalities of inflammatory skin diseases has not been investigated. Full-length VE-cadherin is an insoluble transmembrane protein, whereas the extracellular domain of VE-cadherin is secreted as a soluble protein through a metalloproteinase-dependent mechanism5. Soluble VE-cadherin may function as an antagonist of full-length VE-cadherin, which is suggested by its inhibitory effect on tumor angiogenesis and tumor growth in vivo6. To date, although soluble VE-cadherin has been detected in serum in vivo, the clinical significance of serum soluble VE-cadherin levels is still unknown. Therefore, in this study, we attempted to evaluate the possibility that the serum VE-cadherin level can be a useful marker for inflammatory skin diseases. Serum samples were obtained from 13 patients with AD, 33 patients with psoriasis, and 7 patients with alopecia areata. Control serum samples were also collected from 18 healthy volunteers. Sera of 12 patients with anaphylactoid purpura, 11 patients with cutaneous polyarteritis nodosa, and 6 patients with angiosarcoma were also included as the disease controls. This research was approved by the Ethics Review Committee in Kumamoto University (No. 177). Written informed consents were obtained before patients and healthy volunteers were enrolled into this study according to the Declaration of Helsinki. The serum soluble VE-cadherin levels were measured with a specific enzyme-linked immunosorbent assay kit (R&D Systems, Minneapolis, MN, USA)7 (Fig. 1A). The mean serum VE-cadherin level tended to be lower in patients with AD (1.903 µg/ml) and those with psoriasis (1.915 µg/ml) in comparison to normal subjects (2.511 µg/ml). We found a statistical significance in these decreases (p=0.01 in patients with AD, and p=0.04 in patients with psoriasis). The serum VE-cadherin levels in patients with alopecia (p=0.81), anaphylactoid purpura (p=0.90), cutaneous polyarteritis nodosa (p=0.96), or angiosarcoma (p=0.13) were similar to those in normal subjects. When the cutoff value was set at 1.880 µg/ml on the basis of the normal range provided by the manufacturer, reduced serum VE-cadherin levels were found in 3 of the 18 healthy volunteers (16.7%), 8 of the 13 patients with AD (61.5%), 16 of the 33 patients with psoriasis (48.5%), 1 of the 7 patients with alopecia (14.3%), 4 of the 12 patients with anaphylactoid purpura (33.3%), 2 of the 11 patients with cutaneous polyarteritis nodosa (11.2%), and 0 of the 6 patients with angiosarcoma. Thus, the low serum VE-cadherin levels may be more specific to AD or psoriasis than cutaneous vasculitis or vascular tumor. Fig. 1 (A) Serum soluble VE-cadherin levels in patients with various skin diseases. The serum levels of VE-cadherin determined by using ELISA are shown on the ordinate; the horizontal bars show the mean value in each group. The dotted line indicates the cutoff. ... In the receiver operating characteristic curve analysis of patients with AD (Fig. 1B), the area under curve (AUC) was 0.77 (95% confidence interval [95% CI], 0.59~0.96). An AUC of >0.7 indicates that the serum VE-cadherin levels can effectively distinguish patients with AD from normal subjects. On the other hand, the AUC was 0.67 (95% CI, 0.53~0.82) in patients with psoriasis, indicating that serum VE-cadherin is less useful in diagnosing psoriasis. Accordingly, serum VE-cadherin may be more effective for diagnosing AD than psoriasis. Next, we determined the association of serum VE-cadherin levels with the clinical and serological features of patients with AD (Table 1); 5 disease activity markers (SCORAD, percentage of eosinophil counts, serum lactate dehydrogenase levels, serum thymus and activation-regulated chemokine levels, and serum immunoglobulin E level) and the duration of the disease (between symptom onset and the first visit to the hospital) were evaluated. However, we could not find a significant difference in these factors between patients with reduced VE-cadherin levels and those with normal levels. On the other hand, in patients with psoriasis, when 4 activity indicators (psoriasis area and severity index score, body surface area of the involved skin, arthritis, and nail change) and disease duration were evaluated (Table 1), patients with reduced VE-cadherin levels showed a significantly lower prevalence of nail change (p=0.03). Thus, serum VE-cadherin levels are correlated with clinical symptom in patients with psoriasis but not in patients with AD. Taken together, our results suggest that the serum VE-cadherin level in patients with AD can be the diagnostic marker rather than the disease activity marker, whereas that in patients with psoriasis may be more useful as the marker for disease activity. Table 1 Association of serum VE-cadherin levels with clinical and serological features This is the first report measuring serum VE-cadherin levels in patients with various skin diseases. Furthermore, as far as we searched, decreased serum VE-cadherin levels have not been reported in human diseases. Although the role of VE-cadherin in skin diseases is unknown, skin erythema, for example, is one of the common features of AD and psoriasis and is caused by dilated vessels. As described above, soluble VE-cadherin may function as an antagonist of full-length VE-cadherin. Thus, lower serum soluble VE-cadherin levels may activate transmembrane full-length VE-cadherin, which may contribute to the pathogenesis of AD and psoriasis through erythema formation. Clarifying the mechanism by which VE-cadherin-mediated vascular abnormality contributes to the pathogenesis may lead to the understanding of these diseases and to novel therapeutic strategies. However, this study has a limitation; although the VE-cadherin levels were lower in patients with psoriasis than in healthy volunteers, the nail change is less frequent in patients with psoriasis with decreased VE-cadherin levels. This paradoxical finding may be due to the small number of patients. A larger study with an increased number of patients is needed in the future.

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