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Dive into the research topics where Hironori Niizeki is active.

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Featured researches published by Hironori Niizeki.


The Journal of Allergy and Clinical Immunology | 2014

Application of moisturizer to neonates prevents development of atopic dermatitis

K. Horimukai; Kumiko Morita; Masami Narita; Mai Kondo; Hiroshi Kitazawa; Makoto Nozaki; Yukiko Shigematsu; Kazue Yoshida; Hironori Niizeki; Ken Ichiro Motomura; Haruhiko Sago; Tetsuya Takimoto; Eisuke Inoue; Norio Kamemura; Hiroshi Kido; Junzo Hisatsune; Motoyuki Sugai; Hiroyuki Murota; Ichiro Katayama; Takashi Sasaki; Masayuki Amagai; Hideaki Morita; Akio Matsuda; Kenji Matsumoto; Hirohisa Saito; Yukihiro Ohya

BACKGROUND Recent studies have suggested that epidermal barrier dysfunction contributes to the development of atopic dermatitis (AD) and other allergic diseases. OBJECTIVE We performed a prospective, randomized controlled trial to investigate whether protecting the skin barrier with a moisturizer during the neonatal period prevents development of AD and allergic sensitization. METHODS An emulsion-type moisturizer was applied daily during the first 32 weeks of life to 59 of 118 neonates at high risk for AD (based on having a parent or sibling with AD) who were enrolled in this study. The onset of AD (eczematous symptoms lasting >4 weeks) and eczema (lasting >2 weeks) was assessed by a dermatology specialist on the basis of the modified Hanifin and Rajka criteria. The primary outcome was the cumulative incidence of AD plus eczema (AD/eczema) at week 32 of life. A secondary outcome, allergic sensitization, was evaluated based on serum levels of allergen-specific IgE determined by using a high-sensitivity allergen microarray of diamond-like carbon-coated chips. RESULTS Approximately 32% fewer neonates who received the moisturizer had AD/eczema by week 32 than control subjects (P = .012, log-rank test). We did not show a statistically significant effect of emollient on allergic sensitization based on the level of IgE antibody against egg white at 0.34 kUA/L CAP-FEIA equivalents. However, the sensitization rate was significantly higher in infants who had AD/eczema than in those who did not (odds ratio, 2.86; 95% CI, 1.22-6.73). CONCLUSION Daily application of moisturizer during the first 32 weeks of life reduces the risk of AD/eczema in infants. Allergic sensitization during this time period is associated with the presence of eczematous skin but not with moisturizer use.


Cancer | 2007

Role for connexin 26 in metastasis of human malignant melanoma: communication between melanoma and endothelial cells via connexin 26.

Mamiko Saito-Katsuragi; Hironori Niizeki; Fumitaka Katoh; Mikio Masuzawa; Masahiro Tsutsumi; Hiroki Kuniyasu; Akihiko Ito; Hiroshi Nojima; Sachiko Miyagawa

Connexins form the intercellular channels of the gap junction and play an integral part in a variety of biological functions, such as maintaining tissue homeostasis, cell growth control, and development. Previously it was demonstrated that the expression of connexin 26 (Cx26) can increase the metastatic potential of mouse melanoma cells. The objective of the study was to investigate the role Cx26 plays in the metastasis of human melanoma cells, focusing on the communication between melanoma cells and endothelial cells.


Journal of Dermatological Science | 2012

Identification of mutations in the prostaglandin transporter gene SLCO2A1 and its phenotype–genotype correlation in Japanese patients with pachydermoperiostosis

Takashi Sasaki; Hironori Niizeki; Atsushi Shimizu; Aiko Shiohama; Asami Hirakiyama; Torayuki Okuyama; Atsuhito Seki; Kenji Kabashima; Atsushi Otsuka; Akira Ishiko; Keiji Tanese; Shun Ichi Miyakawa; Jun-ichi Sakabe; Masamitsu Kuwahara; Masayuki Amagai; Hideyuki Okano; Makoto Suematsu; Jun Kudoh

BACKGROUND Pachydermoperiostosis (PDP) is a rare genetic disorder characterized by 3 major symptoms: pachydermia including cutis verticis gyrata (CVG), periostosis, and finger clubbing. Recently, a homozygous mutation in the gene HPGD, which encodes 15-hydroxyprostaglandin dehydrogenase (15-PGDH), was found to be associated with PDP. However, mutations in HPGD have not been identified in Japanese PDP patients. OBJECTIVE We aimed to identify a novel responsible gene for PDP using whole exome sequencing by next-generation DNA sequencer (NGS). METHODS Five patients, including 2 patient-parent trios were enrolled in this study. Entire coding regions were sequenced by NGS to identify candidate mutations associated with PDP. The candidate mutations were subsequently sequenced using the Sanger method. To determine clinical characteristics, we analyzed histological samples, as well as serum and urinary prostaglandin E2 (PGE2) levels for each of the 5 PDP patients, and 1 additional patient with idiopathic CVG. RESULTS From initial analyses of whole exome sequencing data, we identified mutations in the solute carrier organic anion transporter family, member 2A1 (SLCO2A1) gene, encoding prostaglandin transporter, in 3 of the PDP patients. Follow-up Sanger sequencing showed 5 different SLCO2A1 mutations (c.940+1G>A, p.E427_P430del, p.G104*, p.T347I, p.Q556H) in 4 unrelated PDP patients. In addition, the splice-site mutation c.940+1G>A identified in 3 of 4 PDP patients was determined to be a founder mutation in the Japanese population. Furthermore, it is likely that the combination of these SLCO2A1 mutations in PDP patients is also associated with disease severity. CONCLUSION We found that SLCO2A1 is a novel gene responsible for PDP. Although the SLCO2A1 gene is only the second gene discovered to be associated with PDP, it is likely to be a major cause of PDP in the Japanese population.


British Journal of Dermatology | 2005

Intravascular histiocytosis associated with rheumatoid arthritis: report of a case with lymphatic endothelial proliferation

Aiko Okazaki; Hironori Niizeki; Akitaka Nonomura; Sachiko Miyagawa

cin: a clue to the pathogenesis of and therapy for scleroderma? Clin Immunol 2002; 102:209–16. 11 Passiu G, Cauli A, Atzeni F et al. Bleomycin-induced scleroderma: report of a case with a chronic course rather than the typical acute ⁄ subacute self-limiting form. Clin Rheumatol 1999; 18:422–4. 12 Berman B, Duncan MR. Pentoxifylline inhibits the proliferation of human fibroblasts derived from keloid, scleroderma and morphoea skin and their production of collagen, glycosaminoglycans and fibronectin. Br J Dermatol 1990; 123:339–46.


Journal of The American Academy of Dermatology | 2008

Relationship among human herpesvirus 6 reactivation, serum interleukin 10 levels, and rash/graft-versus-host disease after allogeneic stem cell transplantation

Kana Kitamura; Hideyuki Iida; Takaya Fukumoto; Nobuhiko Kobayashi; Hironori Niizeki; Takeshi Morii; Hiroshi Kimura; Sachiko Miyagawa

BACKGROUND The relationship between herpesvirus reactivation and graft-versus-host disease (GVHD) after allogeneic stem cell transplantation (allo-SCT) is unclear. OBJECTIVE We sought to examine the relationship between human herpesvirus (HHV) reactivation and rash/GVHD after allo-SCT by prospective evaluation. METHODS Fifteen patients who had received allo-SCT underwent prospective serial examinations for human herpesvirus 6 (HHV-6), HHV-7, cytomegalovirus, and Epstein-Barr virus DNA in the blood by polymerase chain reaction and real-time polymerase chain reaction. Serum interferon gamma, interleukins 4 and 10, tumor necrosis factor alpha, and soluble interleukin 2 receptor (sIL-2R) were also measured. RESULTS In 10 of 15 patients, macular/papular eruptions were seen after allo-SCT and GVHD was diagnosed. In 8 patients with rash, HHV-6 DNA levels correlated with the cutaneous manifestation. Interleukin 10 and sIL-2R also increased in association with rash. LIMITATIONS The number of patients in our study was relatively small. Not all patients were examined for cytokines and sIL-2R. CONCLUSIONS HHV-6 reactivation may be involved in the pathogenesis of rash/GVHD after allo-SCT.


British Journal of Dermatology | 2002

Genotyping for HLA‐A, B and C alleles in Japanese patients with pemphigus: prevalence of Asian alleles of the HLA‐B15 family

Sachiko Miyagawa; Hironori Niizeki; Yukio Yamashina; T. Kaneshige

Summary Background  There have been only limited reports on major histocompatibility complex class I antigens in pemphigus.


Allergology International | 2016

Transepidermal water loss measurement during infancy can predict the subsequent development of atopic dermatitis regardless of filaggrin mutations

K. Horimukai; Kumiko Morita; Masami Narita; Mai Kondo; Shigenori Kabashima; Eisuke Inoue; Takashi Sasaki; Hironori Niizeki; Hirohisa Saito; Kenji Matsumoto; Yukihiro Ohya

BACKGROUND Atopic dermatitis (AD) is characterized by skin barrier dysfunction. Few studies have used noninvasive techniques to measure epidermis function in asymptomatic neonates. METHODS Data of 116 infants from our previous randomized controlled study were analyzed. Skin barrier function was measured through transepidermal water loss (TEWL), stratum corneum hydration (SCH), and pH. The association between skin barrier function and time to AD development was evaluated. Patients were classified with high or low TEWL, and SCH and pH were assessed. The survival function of the time to AD development and hazard ratios were estimated. Allergic sensitization to egg white and ovomucoid at 32 weeks was assessed. RESULTS Regardless of a filaggrin mutation, TEWL (optimal cutoff, 6.5 g/m(2)/h) of the forehead within the first week of life showed a lower p-value than TEWL of the leg, and the SCH and pH measurements. Baseline TEWL of the forehead was not different between groups, except for the mean gestational age, and it was not affected by humidity. We found a significant difference in the cumulative AD incidence between the high and low TEWL groups for the forehead only (p < 0.05). The probability without AD was lower in the high TEWL group than in the low TEWL group. For only the high TEWL group, AD development decreased significantly with daily emollient use. The high TEWL group exhibited a higher rate of sensitization to ovomucoid (p = 0.07). CONCLUSIONS TEWL of the forehead during the first week of life is associated with AD development.


Clinical & Developmental Immunology | 2012

Distinct Characteristics in Japanese Dermatitis Herpetiformis: A Review of All 91 Japanese Patients over the Last 35 Years

Chika Ohata; Norito Ishii; Takahiro Hamada; Yutaka Shimomura; Hironori Niizeki; Teruki Dainichi; Minao Furumura; Daisuke Tsuruta; Takashi Hashimoto

We reviewed all 91 Japanese dermatitis herpetiformis (DH) patients reported over the last 35 years. The male-to-female ratio was 2 : 1. The mean age at onset was 43.8, and 13 years earlier for female patients. More than half of these Japanese DH patients showed granular IgA deposition in the papillary dermis, and another one-third showed fibrillar IgA deposition. The male patients with granular IgA deposition were 10 years older than those with fibrillar deposition. Whereas patients with granular IgA deposition showed typical distribution of the skin lesions, the predilection sites of DH tended to be spared in patients with fibrillar IgA deposition. Only 3 patients had definite gluten-sensitive enteropathy. There was a statistical difference in the frequency of human leukocyte antigen (HLA)-DR9 between the granular group and controls among Japanese. No patients had HLA-DQ2 or -DQ8, which is frequently found in Caucasian DH patients. The absence of HLA-DQ2/DQ8, the inability to identify celiac disease in most cases, the predominance of fibrillar IgA, and the unusual distribution of clinical lesions in Japanese patients suggest that Japanese DH may be a subset of DH patients and have a pathogenesis which is different from that currently proposed in Caucasian DH patients.


Journal of Dermatology | 2014

Japanese guidelines for the management of pemphigus

Masayuki Amagai; Tomoko Shimizu; Takashi Hashimoto; Shigaku Ikeda; Michiko Kurosawa; Hironori Niizeki; Yumi Aoyama; Keiji Iwatsuki; Yasuo Kitajima

The Committee for Guidelines for the Management of Pemphigus was organized as one element of the Japanese Dermatological Association (JDA) and the Ministry of Health, Labour, and Welfare (MHLW) Research Project on Measures for Research Committee for Intractable Skin Disease. Pemphigus has been defined as a group of intractable autoimmune blistering diseases caused by anti‐desmoglein 1 and/or anti‐desmoglein 3 IgG autoantibodies by the MHLW. The diagnosis of this condition and the criteria for assessing its severity are based on suggestions from the MHLW Research Group. The clinical practice guidelines presented here are those that are currently recommended in Japan. However, symptoms and complications can vary widely among individual pemphigus patients, so not all therapies will be required to be in complete agreement with these guidelines.


Methods | 2002

Polymorphisms in the TNF region confer susceptibility to UVB-induced impairment of contact hypersensitivity induction in mice and humans.

Hironori Niizeki; Hidetoshi Inoko; J. Wayne Streilein

Acute, low-dose ultraviolet B radiation protocols impair induction of contact hypersensitivity (CHS) to highly reactive haptens in some mice and humans (UVB-susceptible) but not others (UVB-resistant). These deleterious effects of ultraviolet radiation appear to be mediated in part by tumour necrosis factor alpha (TNF-alpha), which is released from, or accumulates in, UVB-exposed skin. To test the hypothesis that a polymorphism of the Tnfa locus governs the UVB-S and UVB-R phenotypes, studies have been conducted in genetically disparate strains of mice. Mice carrying the Tnf(d) allele [with precisely 14 (CA) repeats in the promoter region] display the UVB-R phenotype, whereas mice with different Tnf alleles [with (CA) repeats of 14] display the UVB-S phenotype. Molecular genetic studies of the TNF region of HLA in humans displaying either the UVB-S or UVB-R phenotype reveal a significant increase in the frequencies of TNFa2 in UVB-S individuals (P=0.00032) and of TNFd3 in UVB-R individuals (P=0.012). Moreover, DNA sequencing analyses of five single-nucleotide polymorphisms (SNPs) of the TNF promoter region revealed a significant increase in the frequency of TNF/-863A (P=0.015). We propose that the TNF region dictates susceptibility to the deleterious effects of UVB radiation on the induction of contact hypersensitivity in both mice and humans, and that the UVB-S-promoting polymorphisms significantly promote the risk of sunlight-induced skin cancer in humans.

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Kazuhiko Nakabayashi

National Institute of Genetics

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