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Featured researches published by Sakurai K.


Infection and Immunity | 2005

Expression of Genes Encoding Innate Host Defense Molecules in Normal Human Monocytes in Response to Candida albicans

Hee Sup Kim; Eun Hwa Choi; Javed Khan; Emmanuel Roilides; Andrea Francesconi; Miki Kasai; Tin Sein; Robert L. Schaufele; Sakurai K; Chang Gue Son; Braden T. Greer; Stephen J. Chanock; Caron A. Lyman; Thomas J. Walsh

ABSTRACT Little is known about the regulation and coordinated expression of genes involved in the innate host response to Candida albicans. We therefore examined the kinetic profile of gene expression of innate host defense molecules in normal human monocytes infected with C. albicans using microarray technology. Freshly isolated peripheral blood monocytes from five healthy donors were incubated with C. albicans for 0 to 18 h in parallel with time-matched uninfected control cells. RNA from monocytes was extracted and amplified for microarray analysis, using a 42,421-gene cDNA chip. Expression of genes encoding proinflammatory cytokines, including tumor necrosis factor alpha, interleukin 1 (IL-1), IL-6, and leukemia inhibitory factor, was markedly enhanced during the first 6 h and coincided with an increase in phagocytosis. Expression of these genes returned to near baseline by 18 h. Genes encoding chemokines, including IL-8; macrophage inflammatory proteins 1, 3, and 4; and monocyte chemoattractant protein 1, also were strongly up-regulated, with peak expression at 4 to 6 h, as were genes encoding chemokine receptors CCR1, CCR5, CCR7, and CXCR5. Expression of genes whose products may protect monocyte viability, such as BCL2-related protein, metallothioneins, CD71, and SOCS3, was up-regulated at 4 to 6 h and remained elevated throughout the 18-h time course. On the other hand, expression of genes encoding T-cell-regulatory molecules (e.g., IL-12, gamma interferon, and transforming growth factor β) was not significantly affected during the 18-h incubation. Moreover, genes encoding IL-15, the IL-13 receptor (IL-13Ra1), and CD14 were suppressed during the 18-h exposure to C. albicans. Thus, C. albicans is a potent inducer of a dynamic cascade of expression of genes whose products are related to the recruitment, activation, and protection of neutrophils and monocytes.


Surgery Today | 2011

Evaluation of follow-up strategies for corticosteroid therapy of idiopathic granulomatous mastitis

Sakurai K; Shigeru Fujisaki; Enomoto K; Sadao Amano; Masahiko Sugitani

PurposeIdiopathic granulomatous mastitis (IGM) is a rare inflammatory pseudotumor. No therapeutic modality has been established because of the rareness of this disease. The aim of this study was to investigate the clinical course of IGM treated with corticosteroid, and to evaluate the optimal methods of observation during corticosteroid therapy of IGM.MethodsThe retrospective study included eight women who met the required histological criteria of IGM. The clinical data of the presentation, histopathology, and management were analyzed by reviewing the medical records.ResultsThe mean age of the patients was 44.8 years (range, 28–75 years) and all patients complained of a breast mass. Seven of them had pain. All of them underwent a core needle biopsy and were diagnosed as having IGM. Five took prednisolone orally and three received prednisolone plus antibiotics; one patient of the latter group underwent a resection due to severe pain. Seven patients healed without surgery and it took from 4 to 10 months to achieve a cure. The period until confirmation of the disappearance of a mass was the shortest by palpation, followed by contrast magnetic resonance imaging and ultrasonography in that order.ConclusionSteroid therapy was effective for the treatment of IGM, which was cured without surgery in seven of eight cases. Ultrasonography was considered an excellent method for evaluating the treatment outcomes.


Molecular and Clinical Oncology | 2013

Increased IL‑17 production correlates with immunosuppression involving myeloid‑derived suppressor cells and nutritional impairment in patients with various gastrointestinal cancers

Takashi Yazawa; Masahiko Shibata; Kenji Gonda; Takeshi Machida; Satoshi Suzuki; Akira Kenjo; Izumi Nakamura; Takao Tsuchiya; Yoshihisa Koyama; Sakurai K; Tatsuo Shimura; Ryouichi Tomita; Hitoshi Ohto; Mitsukazu Gotoh; Seiichi Takenoshita

Although a causal relationship between inflammation and innate immunity of cancer is more widely accepted today, many of the precise cell mechanisms mediating this relationship have not been elucidated. Th17 cells, which produce the proinflammatory cytokine interleukin 17 (IL-17), have been recognized as one of the key factors in the regulation of inflammatory bowel disease and rheumatoid arthritis. This study demonstrated that, in patients with various types of gastrointestinal cancer, IL-17 production was correlated with myeloid-derived suppressor cell (MDSC) levels and with markers for nutritional impairment, immune suppression and chronic inflammation. IL-17 was significantly higher in patients with various types of gastrointestinal cancer compared to normal volunteers. In addition, IL-17 levels were significantly correlated with neutrophil counts and the neutrophil/lymphocyte ratio (NLR) and significantly inversely correlated with cell-mediated immune response indicators [lymphocyte phytohemagglutinin (PHA)-blastogenesis and IL-12 induction] and patient nutritional status (prealbumin levels). Circulating MDSC levels were significantly correlated with IL-17 production. These results suggest that, in human gastrointestinal cancers, chronic inflammation involving IL-17 may be an important mechanism contributing to disease progression through enhancement of immune suppression or cachexia. Controlling the activation of Th17 cells may prove to be a valuable strategy for the treatment of gastrointestinal cancer patients.


Toxicology | 2011

Aryl hydrocarbon receptor ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin enhances liver damage in bile duct-ligated mice

Jun Ozeki; Shigeyuki Uno; Michitaka Ogura; Mihwa Choi; Tetsuyo Maeda; Sakurai K; Sadanori Matsuo; Sadao Amano; Daniel W. Nebert; Makoto Makishima

The environmental pollutant 2,3,7,8-tetracholorodibenzo-p-dioxin (TCDD) is known to cause a wide variety of toxic effects, including hepatotoxicity, by way of the aryl hydrocarbon receptor (AHR). Although inducible expression of cytochrome P450 (CYP) 1A1 and CYP1A2 is associated with liver injury caused by high-dose TCDD, the specific role of the AHR-CYP1 cascade in hepatotoxicity remains unclear. We investigated the effects of AHR activation under conditions of cholestasis. We administered oral TCDD to mice at a dose that can effectively induce Cyp1 gene expression without overt liver toxicity and then ligated their bile ducts. TCDD pretreatment enhanced bile duct ligation (BDL)-induced increases in liver and plasma bile acids, bilirubin, and aminotransferases. Histology of TCDD-pretreated BDL mice revealed massive hepatic necrosis without any increase in number of apoptotic cells. Whereas induction of AHR-target genes by TCDD was observed similarly in sham-operated as well as in BDL mice, TCDD pretreatment of BDL mice altered the expression of hepatic genes involved in bile acid synthesis and transport. Increased plasma proinflammatory cytokines, tumor necrosis factor and interleukin-1β, in BDL mice were further elevated by TCDD pretreatment. Liver injury by TCDD plus BDL, such as increased plasma bile acids, bilirubin and aminotransferases, liver necrosis, and increased tumor necrosis factor production, was exaggerated in Cyp1a1/1a2(-/-) double knockout mice. These findings indicate that TCDD aggravates cholestatic liver damage and that the presence of CYP1A1 and CYP1A2 plays a protective role in liver damage caused by TCDD and BDL.


Oncology Letters | 2013

Serum levels of vascular endothelial growth factor are increased and correlate with malnutrition, immunosuppression involving MDSCs and systemic inflammation in patients with cancer of the digestive system

Izumi Nakamura; Masahiko Shibata; Kenji Gonda; Takashi Yazawa; Tatsuo Shimura; Takayuki Anazawa; Satoshi Suzuki; Sakurai K; Yoshihisa Koyama; Hitoshi Ohto; Ryouichi Tomita; Mitsukazu Gotoh; Seiichi Takenoshita

Vascular endothelial growth factor (VEGF) reportedly has an important role in the progression of malignant neoplasms and has been reported to induce myeloid-derived suppressor cells (MDSCs) that appear in cancer and inflammation. In the present study, serum concentrations of VEGF were measured in patients with digestive system cancer and the correlations with nutritional damage, immune suppression and systemic inflammation were analyzed. A significant increase in VEGF serum levels was observed in patients with esophageal, gastric and colorectal cancers compared with healthy volunteers. Levels of VEGF were inversely correlated with the serum concentrations of albumin, prealbumin and retinol-binding protein. The serum concentrations of VEGF were inversely correlated with the production of interleukin (IL)-12 and correlated with MDSC counts. VEGF levels were also correlated with neutrophil and neutrophil/lymphocyte counts and inversely correlated with lymphocyte count. Serum VEGF levels were divided at a cutoff of 500 pg/ml, with levels of prealbumin and retinol-binding protein significantly decreased in patients with higher VEGF levels. The stimulation index and IL-12 production were significantly decreased in the group with higher VEGF levels and MDSC counts tended to be higher in this group. These results demonstrated that increased production of VEGF was correlated with systemic inflammation, nutritional impairment and the inhibition of cell-mediated immunity involving MDSCs.


Asian Journal of Surgery | 2007

Primary Hyperparathyroidism with Thyroid Hemiagenesis

Sakurai K; Sadao Amano; Enomoto K; Sadanori Matsuo; Akira Kitajima

Thyroid hemiagenesis is a very rare anomaly. We herein report a case with right thyroid lobe agenesis, which was incidentally found during the assessment of primary hyperparathyroidism. A 42-year-old male presenting with urinary lithiasis was suspected of having primary hyperparathyroidism, and had elevated levels of both serum calcium and intact parathyroid hormone. Both computed tomography and ultrasonography demonstrated the absence of right thyroid lobe and a mass of 1 cm in diameter at the left lower pole of the thyroid. The patient underwent lower left parathyroidectomy, which confirmed the right thyroid hemiagenesis, as well as the absence of both upper and lower right parathyroid glands. The resected left lower parathyroid gland was pathologically diagnosed as adenoma. The postoperative course was favourable and he was discharged on the 2nd day after surgery, without complications.


Oncology Letters | 2017

Myeloid-derived suppressor cells are increased and correlated with type 2 immune responses, malnutrition, inflammation, and poor prognosis in patients with breast cancer

Kenji Gonda; Masahiko Shibata; Tohru Ohtake; Yoshiko Matsumoto; Kazunoshin Tachibana; Noriko Abe; Hitoshi Ohto; Sakurai K; Seiichi Takenoshita

Myeloid-derived suppressor cells (MDSCs) have been identified in the majority of patients and experimental mice with tumors by their suppression of T cell activation. MDSCs have also been reported to be associated with chronic inflammation. In advanced cancer, the T helper (Th) cell balance tends to shift from Th1 to Th2 predominance, and immune function, including cell-mediated immunity, is impaired by cytokines produced by Th2 cells. The present study examined the correlations between MDSC levels and inflammation, immune suppression, malnutrition, and poor prognosis in 155 patients with breast cancer. The levels of MDSCs in preoperative patients and in patients with recurrent breast cancer were significantly higher compared with postoperative patients, patients with recurrent breast cancer who received chemotherapy and healthy volunteers. The MDSC levels of preoperative patients were significantly positively correlated with interleukin (IL)-6 production by peripheral blood mononuclear cells (PBMCs), the neutrophil/lymphocyte ratio and C-reactive protein, and were negatively correlated with the production of interferon-γ and IL-12, serum concentration of rapid turnover protein, and the stimulation index. These patients were divided into two groups based on the levels of MDSCs. In preoperative patients with MDSC levels >1.0% of total PBMCs, the overall survival of patients with stage IV disease was significantly shorter compared with other disease stages, and was also significantly shorter compared with patients with MDSC levels <1.0% of total PBMCs. Thus, the MDSC levels of preoperative patients may function as a good prognostic indicator, particularly in patients with advanced breast cancer.


Toxicology | 2014

Protective role of cytochrome P450 1A1 (CYP1A1) against benzo[a]pyrene-induced toxicity in mouse aorta

Shigeyuki Uno; Sakurai K; Daniel W. Nebert; Makoto Makishima

Benzo[a]pyrene (BaP) is an environmental pollutant produced by combustive processes, such as cigarette smoke and coke ovens, and is implicated in the pathogenesis of atherosclerosis. Cytochrome P450 1A1 (CYP1A1) plays a role in both metabolic activation and detoxication of BaP in a context-dependent manner. The role of CYP1A1 in BaP-induced toxicity in aorta remains unknown. First, we fed Apoe⁻/⁻ mice an atherogenic diet plus BaP and found that oral BaP-enhanced atherosclerosis is associated with increased reactive oxygen species (ROS) and inflammatory markers, such as plasma tumor necrosis factor levels and aortic mRNA expression of vascular endothelial growth factor A (Vegfa). We next examined the effect of an atherogenic diet plus BaP on ROS and inflammatory markers in Cyp1a1⁻/⁻ mice. Although this treatment was not sufficient to induce atherosclerotic lesions in Cyp1a1⁻/⁻ mice, plasma antioxidant levels were decreased in Cyp1a1⁻/⁻ mice even in the absence of BaP treatment. The atherogenic diet plus BaP effectively elevated plasma ROS levels and expression of atherosclerosis-related genes, specifically Vegfa, in Cyp1a1⁻/⁻ mice compared with wild-type mice. BaP treatment increased Vegfa mRNA levels in mouse embryonic fibroblasts from Cyp1a1⁻/⁻ mice but not from wild-type mice. BaP-induced DNA adduct formation was increased in the aorta of Cyp1a1⁻/⁻ mice, but not wild-type or Apoe⁻/⁻ mice, and the atherogenic diet decreased BaP-induced DNA adducts in Cyp1a1⁻/⁻ mice compared with mice on a control diet. These data suggest that ROS production contributes to BaP-exacerbated atherosclerosis and that CYP1A1 plays a protective role against oral BaP toxicity in aorta.


Hepato-gastroenterology | 2012

Ano-neorectal function using manometry on patients after restorative proctocolectomy and ileal J-pouch anal anastomosis for ulcerative colitis in children.

Ryouichi Tomita; Taro Ikeda; Shigeru Fujisaki; Kiminobu Sugito; Sakurai K; Tsugumichi Koshinaga; Masahiko Shibata

BACKGROUND/AIMS The purpose of this study was to clarify the ano-neorectal functions in pediatric patients with soiling at a short period and without soiling at a long period after restorative colectomy and ileal J-pouch anal anastomosis (IPAA) for ulcerative colitis (UC). METHODOLOGY Ten patients after IPAA for UC in childhood were mamometrically studied, aged 10 to 16 years (mean, 13.9 years). Patients after IPAA with ileostomy closure were studied at 6 months (Group A; all patients had soiling) and 3 years after ileostomy closure (Group B; all patients showed continence). Group C served as controls and consisted of 12 subjects (aged 12 to 16 years, mean, 14.8). RESULTS Maximum anal sphincter pressure at rest and maximum anal sphincter pressure during voluntary contraction were significantly lower in group A than in groups B and C. Minimum neorectal sensory threshold volume in group A was significantly higher than in groups B and C (p<0.01). Maximum neorectal tolerated threshold volumes and neorectal compliances, and positive rates of neorectoanal inhibitory reflex, showed no significant difference among the groups. CONCLUSIONS Patients with soiling at 6 months after IPAA showed anal sphincter dysfunction and neorectal sensory dysfunction. The IPAA may cause damage to the ano-neorectal apparatus during rectal mobilization due to the short rectal cuff and mucosectomy.


Surgery Today | 2011

CYP3A4 expression to predict treatment response to docetaxel for metastasis and recurrence of primary breast cancer

Sakurai K; Enomoto K; Sadanori Matsuo; Sadao Amano; Motomi Shiono

PurposeTumors expressing high levels of CYP3A4 are likely to have a poor treatment response to docetaxel (DOC), which is metabolized by CYP3A4. Tissue samples of recurrent breast cancer are sometimes hard to obtain just before treatment because the tumor is often difficult to access. Using immunohistochemistry, we measured CYP3A4 expression in primary lesions and compared their treatment responses to DOC with those of recurrent breast cancer lesions.MethodsThe subjects of this study were 42 patients who had undergone surgery for breast cancer, and had metastasis or recurrence treated by DOC (60 mg/m2 every 3 weeks). Tumor samples resected at surgery were immunostained for CYP3A4 and its expression levels were compared with the response rate to ongoing DOC treatment.ResultsPatients with CYP3A4-negative tumors (n = 19) showed a significantly higher response rate (63.2%) to DOC treatment than did those with CYP3A4-positive tumors (n = 23) (26.1%). The predictive value, negative predictive value, and diagnostic accuracy of CYP3A4 expression in the prediction response to DOC were 63.2%, 73.9%, and 68.6%, respectively.ConclusionsMeasuring CYP3A4 expression immunohistochemically in the primary breast cancer lesion was useful for predicting the treatment response to DOC of tumors that recurred after a long interval.

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Masahiko Shibata

Fukushima Medical University

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