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Dive into the research topics where Akira Sakamaki is active.

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Featured researches published by Akira Sakamaki.


Acta Oto-laryngologica | 1993

Expanded primary T nodules in the palatine tonsils from patients with IgA nephropathy

Makoto Kawaguchi; Takeshi Sakai; Akira Sakamaki; Shin Ishizawa; Yuzo Baba; Yu Masuda; Fumitomo Koizumi

We designed a study to investigate the morphological expression of immune responses in the palatine tonsils from patients with IgA nephropathy. To distinguish between the histological characteristics of the tonsils in habitual tonsillitis (47 patients) and IgA nephropathy (11 patients), we studied the T nodules, B-lymphoid follicles, germinal centers, areas of mixed T and B lymphocytes, lacunar epithelium and connective tissues; then we compared patients with habitual tonsillitis and IgA nephropathy. The T nodules in patients with IgA nephropathy were enlarged, and this change was not accompanied by atrophy of B-lymphoid follicles. Morphologically, primary T nodules were predominant. In reactive lymph nodes, T nodules generally play an important role in the extra-follicular maturation of stimulated B lymphocytes into Ig-secreting plasma cells. Therefore the enlarged primary T nodules remind us that this maturation may occur more frequently in the tonsils of patients with IgA nephropathy than in those with habitual tonsillitis. This suggests that some immunoregulatory dysfunction exists in the secretory immune system of mucosa-associated lymphoid tissues in patients with IgA nephropathy.


Carcinogenesis | 2015

Bcl11b SWI/SNF-complex subunit modulates intestinal adenoma and regeneration after γ-irradiation through Wnt/β-catenin pathway.

Akira Sakamaki; Yoshinori Katsuragi; Kensuke Otsuka; Masanori Tomita; Miki Obata; Tomohiro Iwasaki; Manabu Abe; Toshihiro Sato; Masako Ochiai; Yoshiyuki Sakuraba; Yutaka Aoyagi; Yoichi Gondo; Kenji Sakimura; Hitoshi Nakagama; Yukio Mishima; Ryo Kominami

SWI/SNF chromatin remodeling complexes constitute a highly related family of multi-subunit complexes to modulate transcription, and SWI/SNF subunit genes are collectively mutated in 20% of all human cancers. Bcl11b is a SWI/SNF subunit and acts as a haploinsufficient tumor suppressor in leukemia/lymphomas. Here, we show expression of Bcl11b in intestinal crypt cells and promotion of intestinal tumorigenesis by Bcl11b attenuation in Apc (min/+) mice. Of importance, mutations or allelic loss of BCL11B was detected in one-third of human colon cancers. We also show that attenuated Bcl11b activity in the crypt base columnar (CBC) cells expressing the Lgr5 stem cell marker enhanced regeneration of intestinal epithelial cells after the radiation-induced injury. Interestingly, BCL11B introduction in human cell lines downregulated transcription of β-catenin target genes, whereas Bcl11b attenuation in Lgr5(+) CBCs increased expression of β-catenin targets including c-Myc and cyclin D1. Together, our results argue that Bcl11b impairment promotes tumor development in mouse and human intestine at least in part through deregulation of β-catenin pathway.


PLOS ONE | 2017

Long-term efficacy and safety of nalfurafine hydrochloride on pruritus in chronic liver disease patients: Patient-reported outcome based analyses

Kenya Kamimura; Takeshi Yokoo; Hiroteru Kamimura; Akira Sakamaki; Satoshi Abe; Atsunori Tsuchiya; Masaaki Takamura; Hirokazu Kawai; Satoshi Yamagiwa; Shuji Terai

Background and aim Among various symptoms accompanied with chronic liver disease, pruritus affects the quality of life of patients, causing physical and mental stress, and worsens hepatic function. Recently, κ-opioid receptor agonist, nalfurafine hydrochloride was approved to treat central pruritus in patients with liver disease in Japan. This study aimed to assess the long-term efficacy and safety of nalfurafine hydrochloride on pruritus in chronic liver disease patients. Methods A patient-reported outcome using questionnaire-based methods was used for 41 liver disease patients with or without pruritus symptoms. Nalfurafine hydrochloride (2.5 μg/day) was orally administered to 18 patients suffering from pruritus symptoms and whose current treatment was not effective. The same questionnaires and visual analogue scales (VAS) were repeatedly followed up for the patients for the entire follow-up period, and biochemical analyses were performed to evaluate the safety of the treatment. Results Pruritus completely disappeared in seven of 18 cases, and VAS scores showed a decreasing trend over time from the start of nalfurafine hydrochloride administration in all patients who received the medication. Among 11 patients who were followed up for more than 12 weeks, nine patients showed continuous improvement of symptoms, and this progress was still apparent at ≥20 weeks after starting administration (p < 0.0001). The medication was discontinued in four patients because of progression of primary disease, high cost, oral dryness, and anemia. No significant toxicity was observed on the serum biochemical analyses. Conclusions Nalfurafine hydrochloride contributed to long-term suppression of pruritus without significant safety problems.


Digestive Diseases and Sciences | 2014

Granulocytapheresis for the Treatment of Severe Alcoholic Hepatitis: A Case Series and Literature Review

Kenya Kamimura; Michitaka Imai; Akira Sakamaki; Shigeki Mori; Masaaki Kobayashi; Ken-ichi Mizuno; Manabu Takeuchi; Takeshi Suda; Minoru Nomoto; Yutaka Aoyagi

Severe alcoholic hepatitis has a high mortality rate due to limited therapeutic methods. Although corticosteroids have been used to control the inflammatory response, the outcomes vary and no standardized therapy has been established. Novel therapeutic approaches, such as anti-TNF-α, pentoxifilline, and others have been tested clinically on the basis of their cytokinemic pathophysiology with limited success. However, treatment of leukocytosis that causes cytokinemia and hepatic inflammation in patients via granulocytapheresis and leukocytapheresis showed promising results in a number of reports. Here, we report two cases of severe alcoholic hepatitis treated with granulocytapheresis. The liver function and inflammation recovered after the therapy. A review of 35 cases treated with granulocytapheresis and leukocytapheresis demonstrated their efficacy in treating alcoholic hepatitis by controlling leukocytosis as well as cytokines such as IL-8. Multidisciplinary treatment for severe alcoholic hepatitis should be considered case by case on the basis of the complexity and severity of the condition.


World Journal of Gastroenterology | 2017

Spontaneous regression of hepatocellular carcinoma: A mini-review

Akira Sakamaki; Kenya Kamimura; Satoshi Abe; Atsunori Tsuchiya; Masaaki Takamura; Hirokazu Kawai; Satoshi Yamagiwa; Shuji Terai

Spontaneous tumor regression is an extremely rare phenomenon in the oncology field. However, there are several case reports resulted in the regression of hepatocellular carcinoma (HCC) and the accumulation of clinical information and analyses of the mechanism can contribute to the development of a novel therapy. For this purpose, we have carefully reviewed 23 cases of spontaneously regressed HCC published in recent 5 years and our case. The information regarding the tumor size, tumor marker, treatments, etc., have been summarized. The mechanism of spontaneous regression has been discussed to date and presumed to be due to many factors, including hypoxia and immunological reactions. In this careful review of the 24 cases based on the clinical information, hypoxia, systemic inflammation, and both upon spontaneous regression were seen in 3, 8, and 4 cases, respectively among the 15 cases for which the information regarding the proposed mechanisms are available. Recent development of immunotherapeutic approaches in oncology shows promising results, therefore, accumulation of additional cases and analysis of mechanisms underlying the spontaneous regression of HCC are essential and could lead to the development of a new generation of immunotherapies including antibodies directed against immune reactions.


BMC Cancer | 2016

A diagnostic marker for superficial urothelial bladder carcinoma: lack of nuclear ATBF1 (ZFHX3) by immunohistochemistry suggests malignant progression.

Makoto Kawaguchi; Noboru Hara; Vladimir Bilim; Hiroshi Koike; Mituko Suzuki; Tae-Sun Kim; Nan Gao; Yu Dong; Sheng Zhang; Yuji Fujinawa; Osamu Yamamoto; Hiromi Ito; Yoshihiko Tomita; Yuchi Naruse; Akira Sakamaki; Yoko Ishii; Koichi Tsuneyama; Masaaki Inoue; Johbu Itoh; Masanori Yasuda; Nobuo Sakata; Cha-Gyun Jung; Satoshi Kanazawa; Hiroyasu Akatsu; Hiroshi Minato; Takayuki Nojima; Kiyofumi Asai; Yutaka Miura

BackgroundPathological stage and grade have limited ability to predict the outcomes of superficial urothelial bladder carcinoma at initial transurethral resection (TUR). AT-motif binding factor 1 (ATBF1) is a tumor suppressive transcription factor that is normally localized to the nucleus but has been detected in the cytoplasm in several cancers. Here, we examined the diagnostic value of the intracellular localization of ATBF1 as a marker for the identification of high risk urothelial bladder carcinoma.MethodsSeven anti-ATBF1 antibodies were generated to cover the entire ATBF1 sequence. Four human influenza hemagglutinin-derived amino acid sequence-tagged expression vectors with truncated ATBF1 cDNA were constructed to map the functional domains of nuclear localization signals (NLSs) with the consensus sequence KR[X10-12]K. A total of 117 samples from initial TUR of human bladder carcinomas were analyzed. None of the patients had received chemotherapy or radiotherapy before pathological evaluation.ResultsATBF1 nuclear localization was regulated synergistically by three NLSs on ATBF1. The cytoplasmic fragments of ATBF1 lacked NLSs. Patients were divided into two groups according to positive nuclear staining of ATBF1, and significant differences in overall survival (P = 0.021) and intravesical recurrence-free survival (P = 0.013) were detected between ATBF1+ (n = 110) and ATBF1− (n = 7) cases. Multivariate analysis revealed that ATBF1 staining was an independent prognostic factor for intravesical recurrence-free survival after adjusting for cellular grading and pathological staging (P = 0.008).ConclusionsCleavage of ATBF1 leads to the cytoplasmic localization of ATBF1 fragments and downregulates nuclear ATBF1. Alterations in the subcellular localization of ATBF1 due to fragmentation of the protein are related to the malignant character of urothelial carcinoma. Pathological evaluation using anti-ATBF1 antibodies enabled the identification of highly malignant cases that had been overlooked at initial TUR. Nuclear localization of ATBF1 indicates better prognosis of urothelial carcinoma.


FEBS Open Bio | 2018

Effect of a neural relay on liver regeneration in mice: activation of serotonin release from the gastrointestinal tract

Ryosuke Inoue; Kenya Kamimura; Takuro Nagoya; Norihiro Sakai; Takeshi Yokoo; Ryo Goto; Kohei Ogawa; Yoko Shinagawa-Kobayashi; Yukari Watanabe‐Mori; Akira Sakamaki; Satoshi Abe; Hiroteru Kamimura; Norio Miyamura; Hiroshi Nishina; Shuji Terai

The development of therapeutic options to promote hepatic regeneration following severe liver injury is essential. While humoral factors have been reported as mechanisms of liver regeneration, the contributions of interorgan communication to liver regeneration have not been reported. In this study, we examined the effect of a neural relay on liver regeneration via activation of serotonin release from the gastrointestinal (GI) tract. Our results demonstrated that the afferent visceral nerve from the liver activates the efferent vagus nerve from the brain, leading to activation of serotonin release from the GI tract and contributing to liver regeneration. While it is difficult to apply these results directly to human health, we believe that this study may represent a step toward developing essential therapeutics to promote liver regeneration.


Cancer Biology & Therapy | 2017

Tumor markers for early diagnosis for brain metastasis of hepatocellular carcinoma: A case series and literature review for effective loco-regional treatment.

Kenya Kamimura; Yuji Kobayashi; Yoshifumi Takahashi; Hiroyuki Abe; Daisuke Kumaki; Takeshi Yokoo; Hiroteru Kamimura; Norihiro Sakai; Akira Sakamaki; Satoshi Abe; Masaaki Takamura; Hirokazu Kawai; Satoshi Yamagiwa; Shuji Terai

ABSTRACT Intrahepatic lesions of hepatocellular carcinoma (HCC) have been controlled by significant advances in treatment using loco-regional therapies, including, surgery, ablative therapy, catheter-based chemotherapy, and embolization. Consequently, the number of patients with extrahepatic metastatic lesions has increased. Their prognosis remains poor with approximately <1 y of survival from the time of diagnosis. A molecularly targeted drug, sorafenib, have been used to treat extrahepatic lesions and shown the prolonged survival time. However, the therapeutic benefit for the brain metastasis remains unclear, since it causes intratumor bleeding leading to the severe brain damage. No guidelines for the brain metastasis of HCC have been developed to date due to the shortage of the experiences and evidences. Therefore, the development of standard therapy for brain metastasis following the early diagnosis is essential by accumulating the information of clinical courses and evidences. For this purpose, we reviewed cases of HCC brain metastasis reported to date and analyzed additional 8 cases from our hospital, reviewing 592 advanced HCC cases to estimate the possible metastatic lesions in the brain. With careful review of cases and literature, we suggest that the cases with lung metastasis with increase tendency of tumor markers within recent 3–6 months have higher risks of brain metastasis. Therefore, they should be carefully followed by imaging modalities. In addition, the loco-regional treatment, including surgical resection and radiation therapy should be performed for better prognosis by preventing re-bleeding from the tumors.


Molecular therapy. Nucleic acids | 2017

Efficacy and Safety of Pancreas-Targeted Hydrodynamic Gene Delivery in Rats

Kohei Ogawa; Kenya Kamimura; Yuji Kobayashi; Hiroyuki Abe; Takeshi Yokoo; Norihiro Sakai; Takuro Nagoya; Akira Sakamaki; Satoshi Abe; Kazunao Hayashi; Satoshi Ikarashi; Junji Kohisa; Masanori Tsuchida; Yutaka Aoyagi; Guisheng Zhang; Dexi Liu; Shuji Terai

Development of an effective, safe, and convenient method for gene delivery to the pancreas is a critical step toward gene therapy for pancreatic diseases. Therefore, we tested the possibility of applying the principle of hydrodynamic gene delivery for successful gene transfer to pancreas using rats as a model. The established procedure involves the insertion of a catheter into the superior mesenteric vein with temporary blood flow occlusion at the portal vein and hydrodynamic injection of DNA solution. We demonstrated that our procedure achieved efficient pancreas-specific gene expression that was 2,000-fold higher than that seen in the pancreas after the systemic hydrodynamic gene delivery. In addition, the level of gene expression achieved in the pancreas by the pancreas-specific gene delivery was comparable to the level in the liver achieved by a liver-specific hydrodynamic gene delivery. The optimal level of reporter gene expression in the pancreas requires an injection volume equivalent to 2.0% body weight with flow rate of 1 mL/s and plasmid DNA concentration at 5 μg/mL. With the exception of transient expansion of intercellular spaces and elevation of serum amylase levels, which recovered within 3 days, no permanent tissue damage was observed. These results suggest that pancreas-targeted hydrodynamic gene delivery is an effective and safe method for gene delivery to the pancreas and clinically applicable.


Hepatology | 2017

Intraductal Papillary Neoplasm of the Bile Duct: A Rare Liver Tumor Complicated by Malignancy

Kentaro Tominaga; Kenya Kamimura; Akira Sakamaki; Shuji Terai

Intraductal papillary neoplasm of bile duct (IPNB) in the liver is a rare tumor, accounting for 10% of all bile duct cancers. However, 40% contain carcinoma; thus, an accurate diagnosis followed by surgical treatment is essential. We report the usefulness of contrast-enhanced ultrasound (CEUS) in the detection of potential carcinoma in the tumor by demonstrating minute imaging details and correlating these with histological findings.

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