Akiyoshi Hayashi
Osaka Prefecture University
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Publication
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Journal of Vascular and Interventional Radiology | 2014
Kaishu Tanaka; Noboru Maeda; Keigo Osuga; Yoshiyuki Higashi; Akiyoshi Hayashi; Yumiko Hori; Kentaro Kishimoto; Eiichi Morii; Fumihito Ohashi; Noriyuki Tomiyama
PURPOSE To investigate the pharmacokinetics and chemoembolization efficacy of irinotecan-loaded QuadraSphere microspheres (QSMs) in a rabbit VX2 liver tumor model. MATERIALS AND METHODS Fourteen rabbits with VX2 liver tumors were divided into two groups. In the irinotecan-loaded QSM group (n = 7), 3 mg of QSMs (30-60 μm) containing 12 mg of irinotecan (0.6 mL; 20 mg/mL) were injected into the left hepatic artery. In the control group (hepatic arterial infusion [HAI] and QSMs; n = 7), 3 mg of QSMs suspended in ioxaglic acid were injected following a bolus injection of 0.6 mL of irinotecan solution (20 mg/mL). Sequential irinotecan, SN-38, and SN-38G concentration changes were measured in plasma within 24 hours and at 1 week and in tissues at 1 week. The VX2 tumor growth rates at 1 and 2 weeks were calculated from computed tomographic images. RESULTS All rabbits underwent successful embolization. Plasma irinotecan, SN-38, and SN-38G concentrations in the irinotecan-loaded QSM group showed significantly sustained release compared with the control group (P = .01). Compared with the control group, the irinotecan-loaded QSM group had significantly higher irinotecan concentration in liver tumors (P = .03) and a tendency toward higher SN-38 concentration in liver tumors (P = .29). The SN-38G tissue concentrations were below the limits of quantification. The tumor growth rate was significantly lower and the tumor necrosis rate significantly higher in the irinotecan-loaded QSM group (P = .02 and P = .01, respectively). CONCLUSION Chemoembolization via irinotecan-loaded QSMs more effectively suppresses tumor growth than chemoembolization with unloaded QSMs after HAI. A clinical feasibility study is warranted.
Veterinary Immunology and Immunopathology | 2016
Keiichiro Mie; Terumasa Shimada; Hideo Akiyoshi; Akiyoshi Hayashi; Fumihito Ohashi
We evaluated changes in peripheral blood lymphocyte (PBL) count in dogs following adoptive immunotherapy using lymphokine-activated T killer cells (T-LAK) in combination with surgery. Fifteen tumor-bearing dogs treated with T-LAK therapy combined with palliative resection of tumors were enrolled in the present study. T-LAK were generated from autologous peripheral blood mononuclear cells (PBMC) by culture with recombinant human interleukin -2 (rhIL-2) and solid phase anti-canine cluster of differentiation (CD)3 antibody. T-LAK were administrated intravenously at 2-4-week intervals. After the first administration of T-LAK, counts of PBL and T lymphocyte subsets (CD3(+), CD4(+) and CD8(+) cells) increased and the CD4/CD8 ratio decreased, with significant increases in CD8(+) cells (P<0.05). In 8 tumor-bearing dogs that were administered sequential T-LAK, available data on changes in PBL and T lymphocyte phenotypes until the fifth administration were also analyzed. In tumor-bearing dogs administered 5 rounds of T-LAK, CD8(+) cell counts were maintained high until the fifth administration of T-LAK. Moreover, the CD4/CD8 ratio remained low until the fifth administration of T-LAK. These results indicate that T-LAK therapy combined with surgery may increase peripheral blood T lymphocytes, particularly CD8(+) cells, in tumor-bearing dogs.
Journal of Vascular and Interventional Radiology | 2014
Kentaro Kishimoto; Keigo Osuga; Noboru Maeda; Yoshiyuki Higashi; Akiyoshi Hayashi; Yumiko Hori; Masahisa Nakamura; Fumihito Ohashi; Eiichi Morii; Noriyuki Tomiyama
PURPOSE To determine the arterial distribution and ischemic effects of various particle sizes after transcatheter embolization of the small bowel in a dog model. MATERIALS AND METHODS In 10 dogs, selective microsphere embolization was performed in six branches of the superior mesenteric artery. Microspheres were allocated into three size ranges (100-300 μm, 300-500 μm, and 500-700 μm) and four volume concentrations (0.625%, 1.25%, 2.5%, and 5%). For each size and volume concentration, embolization was performed of five branches at the origin of the last arcade. The distribution of microspheres and the range of ischemic changes of mucosa were evaluated histologically. Angiograms were categorized into two groups: group A, only the vasa recta nonopacified; group B, the last arcade or more proximal branches nonopacified. RESULTS Microspheres sized 100-300 μm penetrated into intramural arteries and 500-700 μm microspheres mainly blocked arteries in the mesentery. There was a significant difference among three sizes in terms of the locations within the vasculature (P < .0001). The larger volume and the smaller size resulted in more ischemia. The range of ischemic changes among three sizes and among four volume concentrations was significantly different (P = .004 and P < .0001, respectively). The range of ischemic changes with 500-700 μm microspheres in group B was significantly greater than in group A (0% in group A vs 83% in group B, P = .001). CONCLUSIONS In a dog model, embolization of the small bowel limited to the vasa recta with the use if 500-700 μm microspheres reduced the range of ischemic changes.
Journal of Veterinary Medical Science | 2016
Katsuhito Sone; Hideo Akiyoshi; Akiyoshi Hayashi; Fumihito Ohashi
A 7-year-old female spayed Labrador Retriever was admitted to our hospital, because of cough with sputum. She was diagnosed as having canine eosinophilic pneumonia (CEP) based on blood eosinophilia, bronchial pattern and infiltrative shadow observed on thoracic radiography, bronchiolar obstruction and air-space consolidation predominantly affecting the right caudal lung lobe, as revealed by computed tomography (CT), predominant eosinophils in CT-guided fine needle aspiration and the clinical course. She exhibited a good response to steroid therapy, and the cough disappeared. The serum surfactant protein (SP)-A level increased with the aggravated symptom and decreased markedly with improvement compared with the C-reactive protein level and the number of eosinophils. We propose that serum SP-A level is a good biomarker in CEP.
Journal of Veterinary Medical Science | 2015
Maki Ishibashi; Akiyoshi Hayashi; Hideo Akiyoshi; Fumihito Ohashi
Recently, hyperbaric oxygen therapy with a lower pressure and oxygen concentration (L-HBOT) than previous methods has been used for dogs in Japan; however, the influences of L-HBOT on dogs have not been clarified. To verify the influences of L-HBOT on physiological mechanism in dogs, we investigated blood gas parameters, glutathione peroxidase (GPx) activity, heart rate variability, stress-related hormones and skin conductance (SC) in 4 clinically normal beagle dogs with catheters in their carotid arteries and jugular veins when they were quiet, after running, after receiving L-HBOT (30% oxygen concentration, 1.3 atmospheres absolute, 30 min) or after not receiving L-HBOT. The results showed there were no changes in blood gas parameters, heart rate variability and catecholamine levels after L-HBOT. GPx activity was significantly higher, and the SC and cortisol level were lower in dogs that received L-HBOT than those when they were quiet. These results suggested that L-HBOT may have a small influence on oxygenation dynamics, activate antioxidant enzymes such as GPx, restrain autonomic nervous activity and control the balance between oxidation and antioxidation inside the body.
Journal of Veterinary Medical Science | 2013
Toshiyuki Tanaka; Terumasa Shimada; Hideo Akiyoshi; Junichiro Shimizu; Cao Zheng; Yijyun Li; Keiichiro Mie; Akiyoshi Hayashi; Mitsuru Kuwamura; Fumio Hoshi; Fumihito Ohashi
ABSTRACT The aim of this study was to evaluate MHC class I expression and prognosis using tumor tissues surgically removed from 9 dogs with mammary gland carcinomas and from 13 dogs with complex carcinomas. We assessed MHC class I expression and its correlation with tumor size, B2M expression, infiltration of lymphocytes, histological grade and prognosis. Hematoxylin and eosin-stained sections were histologically graded using the Elston and Ellis grading method. MHC class I expression on tumor cells was evaluated using the avidin-biotin peroxidase complex method. Loss of MHC class I expression from canine mammary gland carcinomas was significantly correlated with poor prognosis (P<0.05). Loss of MHC class I expression showed no association with poor prognosis in canine mammary gland complex carcinomas, because the data were not balanced. Only 1 of 13 (7.6%) canine mammary gland complex carcinomas showed loss of MHC class I expression. All 13 of these dogs showed good prognosis. Thus, the low frequency of MHC class I expression loss from canine mammary gland complex carcinomas may be associated with good prognosis. Taken together, these results suggest that loss of MHC class I expression may be associated with poor prognosis in canine mammary gland carcinomas.
Journal of Feline Medicine and Surgery | 2012
Toshiyuki Tanaka; Hideo Akiyoshi; Hitoshi Shimazaki; Akinori Sato; Masahiro Inada; Ken-ichi Kiyomiya; Junichiro Shimizu; Zheng Cao; Yijyun Li; Akiyoshi Hayashi; Katsuhito Sone; Tadashi Kitai; Fumihito Ohashi
A 5-month-old male Abyssinian presented with right hemiplegia. Cervical radiographs, haematology and serum biochemistry were normal. A foreign body was identified on computed tomography (CT) and magnetic resonance imaging (MRI). Removal of the foreign body was carried out via a dorsal approach between the occipital bone and the C1 vertebral body using intra-operative CT. No complications were encountered. Thirty days after surgery, the cat was ambulatory.
Journal of Veterinary Medical Science | 2015
Toshie Iseri; Junichiro Shimizu; Hideo Akiyoshi; Kayo Kusuda; Akiyoshi Hayashi; Keiichiro Mie; Takeshi Izawa; Mitsuru Kuwamura; Jyoji Yamate; Yuka Fujimoto; Fumihito Ohashi
A Bengal tiger was presented for evaluation of weakness, ataxia and inappetance. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed a mass extending from the T7-8 vertebral body to the left rib and compressing the spinal cord. On CT, the bone destruction and sequestrum were shown. On MRI, the multilobulated mass appeared hypo- to isointense in T1-weighted and hyperintense in T2-weighted images. The tiger died after imaging, most likely from renal failure. Chordoma without metastasis was diagnosed on necropsy. The imaging characteristics were similar to those found in chordoma in humans. This report describes the use of CT and MRI in an exotic species.
Veterinary Record | 2013
Toshiyuki Tanaka; Terumasa Shimada; Hideo Akiyoshi; Cao Zheng; Keiichiro Mie; Yijyun Li; Akiyoshi Hayashi; Fumihito Ohashi
β2-Microglobulin (β 2M ) forms the invariant chain of major histocompatibility complex (MHC) class I molecules and is essential for their structural stability and optimal functioning (Pedersen and others 1994). Loss or downregulation of MHC class I expression has been reported in various types of cancer (Chang and others 2003, Aptsiauri and others 2007). In human beings, mutations in β 2M are a significant mechanism for the total loss of MHC class I, and β 2M mutations have been described in colon carcinomas, melanomas and lymphomas. The mutational hot spot in β 2M mutations is exon 1 (Garrido and others 1997, Perez and others 1999), although no such mutations have been identified in breast cancers (Chen and others 1996). Several point mutations have been identified in β 2M in healthy domestic dogs, and the data have been deposited in the Broad Institute Dog Genome Project database (CanFam2.0—2,544,508 SNPs; http://www.broadinstitute.org/mammals/dog). However, almost all known canine point mutations remain uncharacterised (Chang and others 2007). To the best of our knowledge, no other group has studied β 2M mutations in canine mammary gland tumours. Therefore, the aim of the present study was to determine β 2M mutations in canine mammary gland simple and complex carcinomas. Approximately 1 g tissue samples were collected from the mammary gland tissues of seven healthy beagles, from the tumours of 11 dogs with mammary gland tumours (one Shih Tzu, two Labrador retrievers, two mixed breeds, one Welsh corgi, two toy poodles, one great Pyrenees, and two papillons), and from normal …
Journal of Veterinary Medical Science | 2013
Katsuhito Sone; Hideo Akiyoshi; Junichiro Shimizu; Zheng Cao; Yijyun Li; Toshiyuki Tanaka; Akiyoshi Hayashi; Shunji Sugii; Fumihito Ohashi
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Obihiro University of Agriculture and Veterinary Medicine
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