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Featured researches published by Masaru Takeuchi.


Ophthalmology | 2013

Use of a Comprehensive Polymerase Chain Reaction System for Diagnosis of Ocular Infectious Diseases

Sunao Sugita; Manabu Ogawa; Norio Shimizu; Tomohiro Morio; Nobuyuki Ohguro; Kei Nakai; Kazuichi Maruyama; Kenji Nagata; Atsunobu Takeda; Yoshihiko Usui; Koh-Hei Sonoda; Masaru Takeuchi; Manabu Mochizuki

PURPOSE To measure the genomic DNA of ocular infectious pathogens in ocular fluids and to analyze the clinical relevance of these pathogens in uveitis and endophthalmitis. DESIGN Prospective clinical case series. PARTICIPANTS A total of 500 patients with infectious uveitis and endophthalmitis were examined at Tokyo Medical and Dental University, Tokyo Medical University, Kyushu University, Osaka University, and Kyoto Prefectural University, all in Japan. METHODS Genomic DNA of bacteria, fungi, parasites, and viruses in collected intraocular samples were examined by comprehensive polymerase chain reaction (PCR). Samples were analyzed first by multiplex PCR and quantitative real-time PCR for human herpes viruses (HHVs) 1 through 8 and toxoplasma. Subsequently, samples were examined by broad-range real-time PCR for bacterial 16S and fungal 18S/28S ribosomal DNA (rDNA). MAIN OUTCOME MEASURES Infectious uveitis and endophthalmitis diagnoses were obtained when using the PCR system. Calculations of the positivity and the diagnostic parameters such as sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) also were evaluated. RESULTS In all of the tested infectious uveitis and endophthalmitis patients, either herpes simplex virus type 1 (n = 18), herpes simplex virus type 2 (n = 4), varicella-zoster virus (n = 55), Epstein-Barr virus (n = 17), cytomegalovirus (n = 68), HHV type 6 (n = 2), toxoplasma (n = 6), bacterial 16S (n = 33), or fungal 18S/28S (n = 11) genome was detected. Neither HHV type 7 nor HHV type 8 DNA was detected in any of the samples. Of the 21 false-negative results found during the PCR analyses, 12 cases were negative for patients clinically suspected of having bacterial endophthalmitis. Conversely, false-positive results for the comprehensive PCR examinations occurred in only 3 cases that subsequently were found to have bacterial 16S rDNA. Diagnostic parameters for the sensitivity, specificity, PPV, and NPV of our PCR examinations were 91.3%, 98.8%, 98.6%, and 92.4%, respectively. CONCLUSIONS Use of our comprehensive PCR assay to examine ocular samples in patients with endophthalmitis and uveitis seems to be clinically useful for detecting infectious antigen DNA. Thus, this PCR method is a reliable tool for both diagnosing ocular disorders and further screening of patients for intraocular infections. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.


Ophthalmology | 2014

Evaluation of the Long-Term Efficacy and Safety of Infliximab Treatment for Uveitis in Behçet's Disease: A Multicenter Study

Masaru Takeuchi; Takeshi Kezuka; Sunao Sugita; Hiroshi Keino; Kenichi Namba; Toshikatsu Kaburaki; Kazuichi Maruyama; Kei Nakai; Kuniaki Hijioka; Etsuko Shibuya; Keiko Komae; Junko Hori; Nobuyuki Ohguro; Koh-Hei Sonoda; Nobuhisa Mizuki; Annabelle A. Okada; Tatsuro Ishibashi; Hiroshi Goto; Manabu Mochizuki

PURPOSE To evaluate the long-term efficacy and safety of infliximab for the treatment of uveitis in Behçets disease (BD). DESIGN Retrospective multicenter study using a questionnaire. PARTICIPANTS A total of 164 consecutive patients with BD treated with infliximab for more than 1 year were studied. The mean age at initiation of infliximab treatment was 42.6±11.7 years, and the mean treatment duration was 32.9±14.4 months. METHODS Data before and at the last visit during infliximab treatment were analyzed in 4 groups divided by duration of treatment: group A (n = 43, 12-<24 months), group B (n = 62, 24-<36 months), group C (n = 42, 36-<48 months), and group D (n = 17, ≥48 months). MAIN OUTCOME MEASURES Best-corrected visual acuity (BCVA), relapse of ocular inflammation, numbers of ocular inflammatory attacks per year, and adverse effects of infliximab therapy. RESULTS The frequency of ocular attacks decreased in all groups (from 5.3±3.0 to 1.0±0.3 in group A, 4.8±4.6 to 1.4±0.3 in group B, 4.1±2.9 to 0.9±0.3 in group C, and 9.5±5.8 to 1.6±0.5 in group D; all P < 0.05). The BCVA was improved in approximately 55% of the eyes after treatment. Mean BCVA converted to logarithm of the minimum angle of resolution was improved after treatment with infliximab in groups A to C (from 0.79±1.04 to 0.59±0.94 in group A, 0.59±1.07 to 0.41±1.04 in group B, and 1.15±1.77 to 0.92±1.73 in group C; all P < 0.05) but not in group D. Uveitis relapsed in 59.1% of all patients after infliximab treatment, and no difference in duration until relapse was observed between individual groups. Approximately 80% of relapses occurred within 1 year after the initiation of infliximab treatment in all groups, 90% of which were controlled by increasing doses of topical corticosteroids and shortening the interval of infliximab infusion. Adverse effects were observed in 65 cases or 35% of all subjects. Infliximab treatment was continued in 85% of the patients, but 15% of the patients discontinued infliximab treatment because of adverse effects or insufficient efficacy. CONCLUSIONS Infliximab reduced the frequency of ocular attacks and improved visual acuity in patients with BD-related uveitis and was generally well tolerated with few serious adverse events.


British Journal of Ophthalmology | 2014

Changes in subfoveal choroidal thickness associated with uveitis activity in patients with Behçet's disease

Sho Ishikawa; Manzo Taguchi; Tadashi Muraoka; Yutaka Sakurai; Takayuki Kanda; Masaru Takeuchi

Aims To evaluate the efficacy of measuring subfoveal choroidal thickness in monitoring uveitis activity before and after treatment with infliximab in patients with Behçets disease (BD)-associated uveitis. Methods Thirteen patients with BD (23 eyes) were selected for this retrospective observational case study. Subfoveal choroidal thickness was measured during active and remission phases of uveitis by enhanced depth imaging–spectral domain optical coherence tomography (EDI-OCT). In five patients (10 eyes), choroidal thickness was assessed at weeks 0, 2, 6 and 14 after the initiation of infliximab treatment. Results Accompanied by excessive dye leakage from choroidal vessels on indocyanine green angiography, dilation of choroidal vessels was observed in the active phase of uveitis by EDI-OCT and the choroidal thickness was significantly greater than that in the remission phase. Treatment with infliximab significantly reduced the choroidal thickness from week 2 after the first infusion, and the reduced choroidal thickness was maintained thereafter. No correlation was found between choroidal thickness and best corrected visual acuity converted to logarithm of the minimum angle of resolution, but choroidal thickness correlated significantly with anterior and posterior ocular inflammation scores. Conclusions This study indicates that measurement of subfoveal choroidal thickness by EDI-OCT is useful for evaluating the activity of uveitis and the therapeutic efficacy in patients with BD.


PLOS ONE | 2015

Elevated Levels of Cytokines Associated with Th2 and Th17 Cells in Vitreous Fluid of Proliferative Diabetic Retinopathy Patients

Masaru Takeuchi; Tomohito Sato; Atsushi Tanaka; Tadashi Muraoka; Manzo Taguchi; Yutaka Sakurai; Yoko Karasawa; Masataka Ito

Macrophages are involved in low-grade inflammation in diabetes, and play pathogenic roles in proliferative diabetic retinopathy (PDR) by producing proinflammatory cytokines. T cells as well as other cells are also activated by proinflammatory cytokines, and infiltration into the vitreous of patients with PDR has been shown. In this study, we measured helper T (Th) cell-related cytokines in the vitreous of PDR patients to define the characteristics of Th-mediated immune responses associated with PDR. The study group consisted of 25 type 2 diabetic patients (25 eyes) with PDR. The control group consisted of 27 patients with epiretinal membrane (ERM), 26 patients with idiopathic macular hole (MH), and 26 patients with uveitis associated with sarcoidosis. Vitreous fluid was obtained at the beginning of vitrectomy, and centrifuging for cellular removals was not performed. Serum was also collected from PDR patients. IL-1β, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, IFN-γ, soluble sCD40L, and TNFα in the vitreous and serum samples were measured. Both percent detectable and levels of IL-4, IL-6, IL-17A, IL-21, IL-22, and TNFα in the vitreous were significantly higher than those in the serum in PDR patients. Vitreous levels of these cytokines and IL-31 were significantly higher in PDR than in ERM or MH patients. Vitreous levels of IL-4, IL-17A, IL-22, IL-31, and TNFα in PDR patients were also significantly higher than those of sarcoidosis patients. In PDR patients, vitreous IL-17A level correlated significantly with vitreous levels of IL-22 and IL-31, and especially with IL-4 and TNFα. Although it is unclear whether these cytokines play facilitative roles or inhibitory roles for the progression of PDR, the present study indicated that Th2- and Th17-related immune responses are involved in the pathogenesis of PDR.


Retina-the Journal of Retinal and Vitreous Diseases | 2014

Profile of intraocular immune mediators in patients with age-related macular degeneration and the effect of intravitreal bevacizumab injection.

Tsuyoshi Agawa; Yoshihiko Usui; Yoshihiro Wakabayashi; Yoko Okunuki; Ma Juan; Kazuhiko Umazume; Takeshi Kezuka; Masaru Takeuchi; Yasuyuki Yamauchi; Hiroshi Goto

Purpose: To measure intraocular cytokine levels in patients with exudative age-related macular degeneration and analyze changes in the cytokine profile 2 days after intravitreal bevacizumab injection. Methods: This prospective case–control study enrolled 37 patients (37 eyes) with age-related macular degeneration including polypoidal choroidal vasculopathy. Twenty-eight age-matched patients (28 eyes) who underwent cataract surgery were used as controls. Undiluted aqueous humor samples were collected after intravitreal bevacizumab injection. Two days after intravitreal bevacizumab injection, cataract surgery was performed and undiluted aqueous humor samples were collected at the beginning of surgery (10 eyes). Twenty-three cytokines were measured using flow cytometry. P values were corrected in multiple comparisons using the conservative Bonferroni–Holm method. The level of significance was set at 0.0022 (0.05/23). Results: At baseline, aqueous humor levels of vascular endothelial growth factor, angiogenin, interferon gamma-inducible protein (IP)-10, macrophage inflammatory protein (MIP)-1&bgr;, monokine induced by interferon &ggr; (Mig), and monocyte chemotactic protein (MCP)-1 were significantly higher in the age-related macular degeneration group than in the control group (P < 0.0022). The result of exploratory multivariate analysis showed that elevated angiogenin level was an important factor that discriminates the two groups (P = 0.0004). Two days after intravitreal bevacizumab injection, vascular endothelial growth factor levels tended to be reduced (P = 0.049), whereas interleukin (IL)-6 and IL-8 levels increased significantly (P < 0.0022). Conclusion: Vascular endothelial growth factor and also angiogenin, IP-10, MCP-1, MIP-1&bgr;, and Mig may be related to the pathogenesis of age-related macular degeneration. Intravitreal bevacizumab injection increases inflammatory cytokine levels, suggesting the induction of an inflammatory process.


British Journal of Ophthalmology | 2014

Prevalence and aetiology of ocular hypertension in acute and chronic uveitis

Takayuki Kanda; Masaki Shibata; Manzo Taguchi; Sho Ishikawa; Kozo Harimoto; Masaru Takeuchi

Aims To evaluate the prevalence and aetiology of intraocular hypertension (OHT) in granulomatous and non-granulomatous uveitis Methods Medical records of 304 consecutive patients (484 eyes) with uveitis who visited the National Defense Medical Collage Hospital between April 2010 and March 2013 were reviewed retrospectively. OHT irrelevant to glaucomatous changes in optic disc or visual field was investigated. Results OHT was found in 123 eyes (25.4%) of 93 uveitic patients (30.6%); 92% of the eyes had open-angle OHT, 45.6% of which was steroid-induced. The prevalence of OHT was 100% (8/8) in Posner–Schlossman syndrome, 50.0% (10/20) in varicella zoster virus-associated iridocyclitis, 45% (9/20) in scleritis, 34.1% (15/44) in Vogt–Koyanagi–Harada disease, 32.1% (18/56) in Behçets disease (BD), 23.1% (6/26) in acute anterior uveitis, and 20.2% (19/94) in sarcoidosis. Pupillary block was observed only in non-granulomatous uveitis, but not in granulomatous uveitis. Seventy percent of OHT in granulomatous uveitis cases was inflammation-induced, while 76.7% in non-granulomatous uveitis cases was steroid-induced. Conclusions OHT in non-granulomatous uveitis was mainly steroid-induced open-angle OHT with some cases of angle-closure OHT caused by pupillary block, while that in granulomatous uveitis was mostly inflammation-induced open-angle OHT with no pupillary block-related angle-closure OHT.


PLOS ONE | 2015

Treatment of Irradiated Mice with High-Dose Ascorbic Acid Reduced Lethality

Tomohito Sato; Manabu Kinoshita; Tetsuo Yamamoto; Masataka Ito; Takafumi Nishida; Masaru Takeuchi; Daizoh Saitoh; Shuhji Seki; Yasuo Mukai

Ascorbic acid is an effective antioxidant and free radical scavenger. Therefore, it is expected that ascorbic acid should act as a radioprotectant. We investigated the effects of post-radiation treatment with ascorbic acid on mouse survival. Mice received whole body irradiation (WBI) followed by intraperitoneal administration of ascorbic acid. Administration of 3 g/kg of ascorbic acid immediately after exposure significantly increased mouse survival after WBI at 7 to 8 Gy. However, administration of less than 3 g/kg of ascorbic acid was ineffective, and 4 or more g/kg was harmful to the mice. Post-exposure treatment with 3 g/kg of ascorbic acid reduced radiation-induced apoptosis in bone marrow cells and restored hematopoietic function. Treatment with ascorbic acid (3 g/kg) up to 24 h (1, 6, 12, or 24 h) after WBI at 7.5 Gy effectively improved mouse survival; however, treatments beyond 36 h were ineffective. Two treatments with ascorbic acid (1.5 g/kg × 2, immediately and 24 h after radiation, 3 g/kg in total) also improved mouse survival after WBI at 7.5 Gy, accompanied with suppression of radiation-induced free radical metabolites. In conclusion, administration of high-dose ascorbic acid might reduce radiation lethality in mice even after exposure.


British Journal of Ophthalmology | 2014

Evaluation of mouse experimental autoimmune uveoretinitis by spectral domain optical coherence tomography

Kohzou Harimoto; Masataka Ito; Yoko Karasawa; Yutaka Sakurai; Masaru Takeuchi

Aims To evaluate the efficacy of spectral domain optical coherence tomography (SD-OCT) in monitoring the development of mouse experimental autoimmune uveoretinitis (EAU) as an animal model of endogenous uveitis, and to develop an OCT-based grading system for EAU severity. Methods C57BL/6 mice were immunised with human interphotoreceptor retinoid-binding protein (amino acid sequence 1–20) peptide and complete Freunds adjuvant to induce EAU. The development of EAU was monitored by SD-OCT serially throughout the disease course, and the images were graded from 1 to 4 and compared with the clinical and histopathological grades. Results SD-OCT images depicted retinal lamella structures including the inner segment/outer segment (IS/OS) line in normal mice. Retinal structural changes were observed on SD-OCT images in mice that developed EAU clinically scored as grade 1 or higher, which precisely corresponded to the pathological findings. The SD-OCT images of EAU were graded as follows: grade 1, a few infiltrating cells in the vitreous and retina; grade 2, increased vitreous cells, retinal vasculitis, and granulomatous lesion; grade 3, cell infiltration into the whole retina, disappearance of IS/OS line, and destruction of the retinal layer structure; and grade 4, disappearance of the outer retina. The SD-OCT grade of EAU based on these criteria correlated significantly with both the clinical grade (R2=0.282, p<0.005) and histopathological grade (R2=0.846, p<0.0001). Conclusions SD-OCT is useful for evaluating the development and severity of mouse EAU. The SD-OCT scoring system we developed accurately reflects clinical and histopathological changes.


Immunotherapy | 2013

A systematic review of biologics for the treatment of noninfectious uveitis

Masaru Takeuchi

Noninfectious uveitis is a potentially sight-threatening ocular disorder and variable therapeutic strategies have been proposed. Biologic therapies were introduced as a new option for patients with uveitis refractory to the conventional therapy using corticosteroids and immunosuppressive agents, and 10 years have passed since the initiation. In this review, the author summarizes current articles on the assessment of therapeutic application of biologics for refractory uveitis including other autoimmune diseases. Although some results are based on investigation with insufficient clinical trials, especially in biologics, the majority of biologics indicate preferable outcomes on refractory uveitis, with remarkable promise to increase the possibility of long-term remissions.


Investigative Ophthalmology & Visual Science | 2013

Hypotensive effect of latanoprost/timolol versus travoprost/timolol fixed combinations in NTG patients: a randomized, multicenter, crossover clinical trial.

Takuhei Shoji; Hiroki Sato; Atsushi Mizukawa; Naoto Hirota; Toshio Enoki; Teruo Kojima; Takayuki Kanda; Masaru Takeuchi

PURPOSE To compare the ocular hypotensive effect of travoprost plus timolol (TTFC) and latanoprost plus timolol fixed combinations (LTFC) in patients with normal-tension glaucoma (NTG). METHODS A two-sequence 12-week, multicenter, prospective, randomized, single-blinded, crossover clinical trial examined 59 NTG patients. If both eyes were eligible, only one eye (chosen at random) was used for analytical purposes. After a 12-week run-in period with dorzolamide plus timolol fixed combination (DTFC), patients were randomized into one of the two crossover sequences of treatment for 12 weeks with TTFC or LTFC and were subsequently crossed over to the alternative treatment for a further 12 weeks. The primary endpoint was reduction in IOP after 12 weeks of each treatment sequence. The effect of treatment on IOP was assessed using a linear mixed model. RESULTS The mean baseline IOP was 14.8 ± 3.3 mm Hg (95% confidence interval [CI], 14.1-15.3 mm Hg) for treatment with DTFC. The TTFC treatment period showed consistently lower mean IOP compared with LTFC treatment period at all measurement time points. Mean reduction in IOP at 12 weeks was significantly greater in the TTFC group than in the LTFC group (-2.4 ± 2.3 mm Hg vs. -1.1 ± 2.3 mm Hg; P = 0.021). No interaction between the drug and treatment sequence was detected. The effects of intraocular lens implantation and measurement time were also not significant. The tolerability profiles of both treatments were similar. CONCLUSIONS The additional reduction in IOP was greater with TTFC than with LTFC, and their tolerability profiles were similar. (http://www.umin.ac.jp/ctr/ number, UMIN 000005974.).

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Masataka Ito

National Defense Medical College

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Tomohito Sato

National Defense Medical College

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Yoko Karasawa

National Defense Medical College

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Manzo Taguchi

National Defense Medical College

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Yutaka Sakurai

National Defense Medical College

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Sho Ishikawa

National Defense Medical College

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Kozo Harimoto

National Defense Medical College

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Tadashi Muraoka

National Defense Medical College

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Takayuki Kanda

National Defense Medical College

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