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Dive into the research topics where Yoshihisa Fujikura is active.

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Featured researches published by Yoshihisa Fujikura.


Urologia Internationalis | 2005

Lower Incidence of Inguinal Hernia: Minilaparotomy Radical Retropubic Prostatectomy Compared with Conventional Technique

Takeo Nomura; Hiromitsu Mimata; Hirokazu Kitamura; Yoshihisa Fujikura; Yasuyuki Akita; Mutsushi Yamasaki; Daisaku Nakano; Yoshihisa Tasaki; Yoshio Nomura

Introduction: The purpose of the present study was to compare the incidence of inguinal hernias after conventional and minilaparotomy (minilap) radical retropubic prostatectomy (RRP). Patients and Methods: In this retrospective study, we review our experience with 70 consecutive patients with prostate cancer who underwent prostatectomy from April 1995 through March 2001. Of these, 35 patients had conventional RRP, and 35 patients had minilap RRP. Results: Conventional RRP and minilap RRP groups were similar in body mass index (mean 24.4 and 23.5), operative time (mean 260 and 241 min), previous lower abdominal operation record (mean 37.1 and 25.7%), and post-prostatectomy anastomotic strictures (mean 11.4 and 14.3%). The volume of the estimated blood loss was significantly less for minilap RRP (mean 1,220 ml) than for conventional RRP (mean 1,666 ml; p = 0.0194). The incidence of postoperative inguinal hernias was 17.1% (6 of 35), 2.9% (1 of 35), and 3.2% (1 of 31) in conventional RRP, minilap RRP, and unoperated groups, respectively. The incidence of inguinal hernias after minilap RRP was significantly lower than after conventional RRP (p = 0.0464). Seven patients with postoperative inguinal hernias had a high incidence of postoperative strictures (42.9%), while 63 patients without hernia had a low incidence (9.5%). There was a significant difference in developing postoperative strictures between patients with hernia and those without (p = 0.0124). While postoperative stricture and operative technique were different in the hernia and hernia-free groups on univariate analysis, multivariate logistic analysis revealed that the operative technique was an independent factor for the occurrence of inguinal hernias (p = 0.0419). Conclusion: Minilap RRP compares favorably with conventional RRP in view of the postoperative inguinal hernia development.


American Journal of Physiology-lung Cellular and Molecular Physiology | 2010

Direct inhibition of arginase attenuated airway allergic reactions and inflammation in a Dermatophagoides farinae-induced NC/Nga mouse model

Noriko Takahashi; Keiki Ogino; Kei Takemoto; Seiji Hamanishi; Da Hong Wang; Tomoko Takigawa; Masafumi Shibamori; Hironobu Ishiyama; Yoshihisa Fujikura

The expression of arginase I has been a focus of research into the pathogenesis of experimental asthma, because arginase deprives nitric oxide synthase (NOS) of arginine and therefore participates in the attenuation of bronchodilators such as nitric oxide (NO). The present study used an intranasal mite-induced NC/Nga mouse model of asthma to investigate the contribution of arginase to the asthma pathogenesis, using an arginase inhibitor, N(omega)-hydroxy-nor-l-arginine (nor-NOHA). The treatment with nor-NOHA inhibited the increase in airway hyperresponsiveness (AHR) and the number of eosinophils in bronchoalveolar lavage fluid. NOx levels in the lung were elevated despite suppressed NOS2 mRNA expression. Accompanied by the attenuated activity of arginase, the expression of arginase I at both the mRNA and protein level was downregulated. The levels of mRNA for T helper 2 cytokines such as IL-4, IL-5, and IL-13, and for chemotactants such as eotaxin-1 and eotaxin-2, were reduced. Moreover, the accumulation of inflammatory cells and the ratio of goblet cells in the bronchiole were decreased. The study concluded that the depletion of NO caused by arginase contributes to AHR and inflammation, and direct administration of an arginase inhibitor to the airway may be beneficial and could be of use in treating asthma due to its anti-inflammatory and airway-relaxing effects, although it is not clear whether the anti-inflammatory effect is direct or indirect.


PLOS ONE | 2014

Allergic airway inflammation by nasal inoculation of particulate matter (PM2.5) in NC/Nga mice.

Keiki Ogino; Ran Zhang; Hidekazu Takahashi; Kei Takemoto; Masayuki Kubo; Ikuo Murakami; Da Hong Wang; Yoshihisa Fujikura

To evaluate the effect of airborne particulate matter 2.5 (PM2.5) in winter on airway inflammation, water-soluble supernatant (Sup) and water-insoluble precipitate (Pre) in PM2.5 were inoculated in NC/Nga mice with high sensitivity to mite allergens. Sup with aluminum oxide was injected intraperitoneally for sensitization. Five days later, Sup, Pre or both Sup and Pre were inoculated via the nasal route five times for more sensitization and a challenge inoculation on the 11th day in NC/Nga mice. On the 12th day, mice were examined for airway hyperresponsiveness (AHR), BALF cell count and IL-1β concentration, mRNA expression of Th1 and Th2 cytokines, chemokines such as eotaxin 1 and eotaxin 2, inflammasomal complex molecules such as IL-1β, caspase 1 and the nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) in lung tissue as well as histopathology. The synergistic effect of Sup and Pre was observed in terms of increases in AHR, BALF cells, the mRNA expression of IL-13, eotaxin1 and IL-1β, and the IL-1β concentration in BALF. Intracellular deposits of insoluble particulates were observed in macrophages around inflammatory granulation of the mouse group treated with Sup and Pre. These results suggest that PM2.5 can induce airway hyperresponsiveness in mice with genetically high sensitivity to mite allergens by an inflammasome-associated mechanism and synergistic action of insoluble particulates and soluble components.


Free Radical Research | 2013

Inhibition of arginase ameliorates experimental ulcerative colitis in mice

Y. Akazawa; Masayuki Kubo; Ran Zhang; K. Matsumoto; F. Yan; Heri Setiawan; Hidekazu Takahashi; Yoshihisa Fujikura; Keiki Ogino

Abstract Nitric oxide (NO) is produced from the conversion of L-arginine by NO synthase (NOS) and regulates a variety of processes in the gastrointestinal tract. Considering the increased activity of arginase in colitis tissue, it is speculated that arginase could inhibit NO synthesis by competing for the same L-arginine substrate, resulting in the exacerbation of colitis. We examined the role of arginase and its relationship to NO metabolism in dextran sulfate sodium (DSS)-induced colitis. Experimental colitis was induced in mice by administration of 2.5% DSS in drinking water for 8 days. Treatment for arginase inhibition was done by once daily intraperitoneal injection of Nω-hydroxy-nor- arginine (nor-NOHA). On day 8, we evaluated clinical parameters (body weight, disease activity index, and colon length), histological features, the activity and expression of arginase, L-arginine content, the expression of NO synthase (NOS), and the concentration of NO end-product (NOx: nitrite + nitrate). Administration of nor-NOHA improved the worsened clinical parameters and histological features in DSS-induced colitis. Treatment with nor-NOHA attenuated the increased activity of arginase, upregulation of arginase Ι at both mRNA and protein levels, and decreased the content of L-arginine in colonic tissue in the DSS-treated mice. Conversely, despite the decreased expression of NOS2 mRNA, the decreased concentration of NOx in colonic tissues was restored to almost normal levels. The consumption of L-arginine by arginase could lead to decreased production of NO from NOS, contributing to the pathogenesis of the colonic inflammation; thus, arginase inhibition might be effective for improving colitis.


Journal of Dermatological Science | 2010

Epiplakin accelerates the lateral organization of keratin filaments during wound healing

Kazushi Ishikawa; Hideaki Sumiyoshi; Noritaka Matsuo; Naoko Takeo; Mizuki Goto; Osamu Okamoto; Shuji Tatsukawa; Hirokazu Kitamura; Yoshihisa Fujikura; Hidekatsu Yoshioka; Sakuhei Fujiwara

BACKGROUND Epiplakin (EPPK) belongs to the plakin family of cytolinker proteins and, resembling other members of the plakin family such as BPAG1 (an autoantigen of bullous pemphigoid) and plectin, EPPK has plakin repeat domains (PRDs) that bind to intermediate filaments. Elimination of EPPK by gene targeting in mice resulted in the acceleration of keratinocyte migration during wound healing. EPPK is expressed in proliferating keratinocytes at wound edges and, in view of its putative function in binding to keratin, we postulated that the keratin network in EPPK-null (EPPK(-/-)) mice might be disrupted during wound healing. OBJECTIVE To examine this hypothesis and to determine the precise localization of EPPK in relation to keratin filaments, we compared the non-wounded and wounded epidermis of wild-type and EPPK(-/-) mice. METHODS Non-wounded epidermis and wounded epidermis from wild-type and EPPK(-/-) mice were examined by immunofluorescence staining and electron microscopy before and after double immunostaining. RESULTS EPPK was colocalized with keratin 17 (K17) more extensively than with other keratins examined in wounded epidermis. The expression of K5, K10, K6, and K17 was the same in EPPK(-/-) mice after wounding as in normal mice, but diameters of keratin filaments were reduced in EPPK(-/-) keratinocytes. Electron microscopy after immunostaining revealed that EPPK colocalized with K5, K10 and K6 after wounding in wild-type mice. CONCLUSION Our data indicate that EPPK accelerates keratin bundling in proliferating keratinocytes during wound healing and suggest that EPPK might contribute to reinforcement of keratin networks under mechanical stress.


Neuroscience Research | 2012

Administration of antisense DNA for GPR39-1b causes anxiolytic-like responses and appetite loss in rats

Yoshinobu Ishitobi; Jotaro Akiyoshi; Shuhei Honda; Taiga Ninomiya; Masayuki Kanehisa; Yoshihiro Tanaka; Jusen Tsuru; Koichi Isogawa; Hirokazu Kitamura; Yoshihisa Fujikura

The G protein-coupled receptor 39-b (GPR39-1b) is a splice variant of which is expressed in the central nervous and gastrointestinal systems. Previously, GPR39-1b was proposed to be the receptor for obestatin, but current evidence does not support this hypothesis. The purpose of the present work was to identify the role of GPR39-1b in anxiety and eating behaviors. Antisense oligonucleotides were infused at a constant rate into the cerebral lateral ventricles of rats and their effect on anxiety-like behavior and food intake was monitored. GPR39-1b antisense oligonucleotides produced anxiolytic-like effects in the elevated-plus maze test and in the black and white box test. Antisense oligonucleotides also decreased food intake. These results indicate that inhibition of GPR39-1b induces a decrease in anxiety-related behaviors and disturbs appetite.


Journal of Clinical Biochemistry and Nutrition | 2012

Regulation of nitric oxide generation by up-regulated arginase I in rat spinal cord injury

Takashi Imagama; Keiki Ogino; Kei Takemoto; Yoshihiko Kato; Hideo Kataoka; Hidenori Suzuki; Zhang Ran; Heri Setiawan; Yoshihisa Fujikura; Toshihiko Taguchi

Recently, arginase is suggested to regulate nitric oxide production by competing with nitric oxide synthase for the same substrate, L-arginine, in experimental asthma. We investigated the role of arginase and its relationship to nitric oxide production after spinal cord injury. Rats were subjected to laminectomy and complete transection of their spinal cords (injury group) or laminectomy only (sham group). In the injury group, arginase I was increased in the macrophages at the transection edge, and the peak was observed 48 h after spinal cord injury. However, nitric oxide production decreased significantly in the injury group despite increased nitric oxide synthase2 mRNA expression compared with the sham group. We also demonstrated the reduction in L-arginine concentrations, which was inversely associated with changes in arginase activity. Therefore, arginase appeared to regulate nitric oxide production by consuming L-arginine. The regulation of arginase activity and L-arginine levels may improve nitroxidative stress and reduce tissue damage in spinal cord injury.


Environmental Toxicology | 2014

Inflammatory airway responses by nasal inoculation of suspended particulate matter in NC/Nga mice.

Keiki Ogino; Noriko Takahashi; Masayuki Kubo; Akihito Takeuchi; Motoharu Nakagiri; Yoshihisa Fujikura

To evaluate the allergic effect of airborne particulate matter (PM) on the airway, separated soluble supernatant (Sup) and insoluble precipitate (Pre) in suspended PM were inoculated into NC/Nga mice with a high sensitivity for mite allergens. Sup, Pre, or both Sup and Pre with or without pronase treatment were inoculated via the nasal route five times for sensitization and a challenge inoculation on the 11th day in NC/Nga mice. On the 14th day, mice were examined for airway hyperresponsiveness (AHR), bronchoalveolar lavage fluid (BALF) cell count, mRNA expression of Th1 and Th2 cytokines in the lung tissue, and histopathology. Synergistic effects of Sup and Pre were observed as increases in AHR and a histopathological change of Periodic acid‐Schiff (PAS) staining. Increases in neutrophils, macrophages, and lymphocytes of BALF cells were dependent on Pre. The expression of IL‐4 mRNA was increased by Sup, and those of IL‐5 mRNA and Il‐13 mRNA was increased by Sup and Pre. Augmented AHR, mRNA expression of IL‐4, peribronchial inflammation, and PAS staining by Sup plus Pre were attenuated by treatment of Sup with pronase to digest proteins. These results suggest that some proteins of ambient PM may be important environmental factors for AHR and airway inflammation with the aid of insoluble particulates, although some soluble factors such as endotoxins cannot be ruled out.


Environmental Toxicology | 2017

PM2.5-induced airway inflammation and hyperresponsiveness in NC/Nga mice

Keiki Ogino; Kenjiro Nagaoka; Tomoaki Okuda; Akira Oka; Masayuki Kubo; Eri Eguchi; Yoshihisa Fujikura

The allergic inflammatory effects of particulate matter (PM) 2.5, collected with the cyclone system in Yokohama city in Japan, were investigated in NC/Nga mice, which are hypersensitive to mite allergens. PM2.5 with alum was injected intraperitoneally for sensitization. Five days later, 200 μg of PM2.5 in 25 μL of saline was administered to mice intranasally five times for further sensitization. On the 11th day, PM2.5 was administered as a challenge. On the 12th day, mice were examined for airway hyperresponsiveness (AHR), the bronchoalveolar lavage fluid (BALF) cell count, mRNA expression of Th1, Th2 cytokines, and metallothioneins in lung tissue, and histopathology. PM2.5 increased AHR, total cell numbers including eosinophils in BALF, and mRNA levels of IL‐5, IL‐22, eotaxin, eotaxin 2, and metallothionein 3. In PM2.5‐induced lungs, inflammation was observed around the bronchus. These results demonstrate that PM2.5 alone, collected with the cyclone system in Yokohama city in Japan, induces asthma‐like airway inflammation.


PLOS ONE | 2015

A Clinical Approach to Brown Adipose Tissue in the Para-Aortic Area of the Human Thorax

Huixing Wei; Seiichi Chiba; Chinatsu Moriwaki; Hirokazu Kitamura; Keisuke Ina; Taishi Aosa; Kenichiro Tomonari; Koro Gotoh; Takayuki Masaki; Isao Katsuragi; Hitoshi Noguchi; Tetsuya Kakuma; Kazuyuki Hamaguchi; Tatsuo Shimada; Yoshihisa Fujikura; Hirotaka Shibata

Background Human thoracic brown adipose tissue (BAT), composed of several subdivisions, is a well-known target organ of many clinical studies; however, the functional contribution of each part of human thoracic BAT remains unknown. The present study analyzed the significance of each part of human thoracic BAT in the association between regional distribution, cellularity, and factors involved in the functional regulation of thoracic BAT. Methods We analyzed 1550 healthy adults who underwent medical check-ups by positron-emission tomography and computed tomography (PET–CT) imaging, 8 cadavers, and 78 autopsy cases in an observational study. We first characterized the difference between the mediastinum and the supraclavicular areas using counts of BAT detection and conditions based on PET–CT outcomes. The measurable important area was then subjected to systematic anatomical and immunohistochemical analyses using anti-uncoupling protein 1 (UCP1) antibody to characterize the cellularity in association with age and sex. Results In PET–CT scanning, the main site of thoracic BAT was the mediastinum rather than the supraclavicular area (P < 0.05). Systemic macroanatomy revealed that the thumb-sized BAT in the posterior mediastinal descending para-aortic area (paBAT) had feeding vessels from the posterior intercostal arteries and veins and sympathetic/parasympathetic innervation from trunks of the sympathetic and vagus nerves, respectively. Immunohistochemical analysis indicated that the paBAT exhibited immunoreactivity for tyrosine hydroxylase and vesicular acetylcholine transporter located in the pericellular nervous fibers and intracellular UCP1. The brown adipose cells of paBAT showed age-dependent decreases in UCP1 expression (P < 0.05), accompanied by a significant increase in vacuole formation, indicating fat accumulation (P < 0.05), from 10 to 37 years of age (P < 0.01). Conclusions paBAT may be one of the essential sites for clinical application in BAT study because of its visible anatomy with feeding vessels and sympathetic/parasympathetic innervation functionally affected by outer condition and senescence.

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