Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Masahisa Kyogoku is active.

Publication


Featured researches published by Masahisa Kyogoku.


Journal of The American Academy of Dermatology | 2009

Analysis of CXCL9 and CXCR3 expression in a case of intravascular large B-cell lymphoma

Maymi Kato; Koichi Ohshima; Masahiro Mizuno; Masahisa Kyogoku; Keiko Hashikawa; Yoshiki Tokura; Yoshiki Miyachi; Kenji Kabashima

Intravascular large B-cell lymphoma is a rare disease with multiorgan involvement that also affects the skin. Skin manifestations include purpuric to red macules, plaques, or nodules with occasional edema and tenderness. We report a 68-year-old woman with bilateral leg edema and occasional high fever. A biopsy specimen from a subcutaneous nodule showed that the blood vessels in the dermis and subcutaneous tissue were filled with irregularly shaped chromatin-rich large atypical lymphocytes positive for CD20 and bcl-2, consistent with the diagnosis of intravascular large B-cell lymphoma. In addition, immunohistochemical analysis showed expression of CXCR3 in the atypical lymphocytes; its ligand, CXCL9, was detected in blood vessels. Although limited to a single case, our study could provide a possible new clue to the pathogenesis of intravascular large B-cell lymphoma by virtue of the characteristic expression of CXCL9-CXCR3.


European Journal of Cardio-Thoracic Surgery | 2013

Aortic dissection in the outer third of the media: what is the role of the vasa vasorum in the triggering process?

Hiroaki Osada; Masahisa Kyogoku; Motonori Ishidou; Manabu Morishima; Hiroyuki Nakajima

OBJECTIVES Extensive clinicopathological analyses of aortic dissection have implicated hypertension and genetic abnormalities as the major pathogenic mechanisms. However, previous findings from pathological examinations have often been inconsistent with these mechanisms. In this paper, we suggest a significant role for the vasa vasorum in the aetiology and pathogenesis of aortic dissection. METHODS We reviewed records of patients who underwent thoracic aortic dissection repair at our institution between June 2008 and August 2011. Twenty-one patients (10 men, 11 women; mean age, 65.0 ± 12.0 years) underwent surgery with subsequent histopathological examination of the aortic wall. We evaluated the history and histopathological findings of these patients. RESULTS Aortic medial changes were observed in all 21 patients. These changes included thinning and sometimes fragmentation of the elastic lamina, as well as atrophy of the smooth muscle cells, with surrounding accumulation of an Alcian blue-positive mucinous substance, mostly adjacent to the dissection. Importantly, the dissection was located in the outer third of the media in 20 of the 21 patients (95.2%). Of these 20, 18 showed histopathological evidence of sclerotic changes of the vasa vasorum, including muscular hyperplasia, elastosis, intimal fibrosis and/or luminal obstruction, and even rupture. These changes may have been secondary to hypertension or peri-aortic changes, leading to degenerative changes in the aortic media and even initiation of dissection. CONCLUSIONS Most aortic dissections initially developed in the outer third of the media alongside the vasa vasorum. In this type of aortic dissection, dysfunction of the vasa vasorum may play a key role in long-standing ischaemia or malnutrition of the aortic media.


Cardiovascular Pathology | 2016

Coronary artery bypass graft in a patient with Fabry's disease

Hiroaki Osada; Naoki Kanemitsu; Masahisa Kyogoku

Fabrys disease is a lysosomal storage disease characterized by intracellular accumulation of ceramide trihexoside resulting from alpha-galactosidase A deficiency. While the heart is often involved, coronary artery disease and its management in Fabrys disease patients are extremely rare clinical entities. We report a case of a 72-year-old man with left main disease in Fabrys disease with special consideration of the arterial wall pathology.


Asian Cardiovascular and Thoracic Annals | 2015

Partial aortic root replacement for aneurysm of the right sinus of Valsalva.

Hiroaki Osada; Masahisa Kyogoku; Takahisa Fujino; Hiroyuki Nakajima

An aneurysm of the sinus of Valsalva is clinically rare, and its operative indications and procedures are controversial. We herein report the rare case of a 68-year-old woman with severe right ventricular outflow tract obstruction caused by an aneurysm of the right sinus of Valsalva. We performed partial aortic root reconstruction using a bovine pericardial patch, and aortic valve replacement. Although this case provides evidence that these are suitable surgical techniques for treatment of aneurysm of the sinus of Valsalva, total aortic root replacement should have been chosen based on the pathological finding of aortic medial and valve degeneration.


Interactive Cardiovascular and Thoracic Surgery | 2018

Histopathological evaluation of aortic dissection: a comparison of congenital versus acquired aortic wall weakness

Hiroaki Osada; Masahisa Kyogoku; Tekehiko Matsuo; Naoki Kanemitsu

OBJECTIVES The aim of this study was to identify pathological changes of aortic dissection based on histopathological evaluation of aortic wall weakness by comparing patients with and without congenital abnormalities. METHODS We reviewed records of patients who underwent repair for dissection-related aortic disease between 2008 and 2015. Fifty patients (20 men and 30 women; mean age 66.9 ± 14.0 years) who underwent surgery with subsequent histopathological examination of the aortic wall were divided into 2 groups. Group 1 had congenital abnormalities, including Marfan syndrome and bicuspid aortic valve (n = 5), and Group 2 had no congenital abnormalities (n = 45). We compared the histopathological characteristics of the aortic wall in these patients. RESULTS There were significant differences in age and body surface area between the 2 groups. Although 80% of Group 1 patients developed dissection at the middle of the media, all Group 2 patients developed dissection at the outer one-third of the media, which is along the pathway of the vasa vasorum of the aortic wall. Both groups showed the same extent of degeneration of the vasa vasorum. Group 1 showed a severe score of mucoid extracellular matrix accumulation in the aortic media. CONCLUSIONS Although it may be multifactorial, congenital maldevelopment of the media tends to result in dissection of the centre of the media, and acquired aortic wall weakness is concentrated in the outer third of the media. Degeneration of the vasa vasorum may be an important emerging substrate for developing aortic dissection.


Anz Journal of Surgery | 2018

Primary biphasic synovial sarcoma of the right atrium

Hiroaki Osada; Masahisa Kyogoku; Hiroyuki Nakajima; Ryuzo Sakata

Cardiac synovial sarcoma is an extremely rare malignant neoplasm. We present here the surgical resection case of a 46-year-old man with a primary biphasic right atrial synovial sarcoma. A healthy 46-year-old man presented with asymptomatic thirddegree atrioventricular block detected at annual check-up. Transthoracic echocardiography showed left ventricular ejection fraction of 75% (using modified Simpson’s biplane method), mild tricuspid regurgitation and a large, spherical 38 × 43 mm solid mass with homogenous echogenicity arising from the tricuspid atrioventricular junction and prolapsing into the ventricular cavity during the cardiac cycle (Fig. 1a, Video S1). Coronary angiography revealed no significant obstructive disease. Surgery was performed with cardiopulmonary bypass. The tumour has a smooth surface and not polypoid (Fig. 1b) and was located just outside the posterior tricuspid annulus, attached by a 2 × 2 cm stalk. The remainder of the right atrial wall appeared grossly normal. The tumour was completely resected, along with a margin of slightly hypertrophied neighbouring endocardium with sparing muscle layer. The defect was cryoablated twice and reconstructed with an autopericardial patch. There was no further tricuspid valve regurgitation. The patient had an uneventful post-operative course and was discharged on post-operative day 15 after dual chamber pacemaker implantation. The resected tumour was 55 × 40 × 38 mm, hard and potatoshaped; its cut surface was milky yellowish and contained a small cyst. Post-operative tumour histopathology revealed a biphasic growth pattern with a mixture of packed vimentin positive spindle cells and cytokeratin (AE1/AE3) and CD99 positive adenosquamous glandular-like cells (Figs 2a–c, 3a–e). Alfa-SMA, desmin, F-VIII, HHF-35, S-100, CD31 and CD34 were all negative in the tumour cells. Ki67 activity was about 10 cells per 10 high power fields (HPF) (Fig. 3f). The SS18-SSX2 chromosome fusion was confirmed later. The tumour was eventually diagnosed as a synovial sarcoma of the right atrium. While whole body positron emission tomography (PET) and computed tomography revealed neither invasive nor metastatic lesions, the histology of the endocardium near the tumour stalk indicated the presence of sarcomatous tumour (Fig. 2d). Hence, 2 months after initial surgery, before commencing adjuvant chemotherapy, the patient underwent right atrial endocardium resection around the primary site, tricuspid septal, posterior annulus and coronary sinus. Intraoperative rapid diagnosis confirmed no remaining microscopic residual disease. The large defect was reconstructed with a bovine pericardial patch. The patient has received adjuvant chemotherapy with gemcitabine and docetaxel, and is alive without recurrence 13 months after initial surgery. During this period, we used echocardiography every 3 months and PET every 6 months after surgery for follow-up. Cardiac synovial sarcomas are extremely rare malignant neoplasms, with the clinical and pathological characteristics still unclear. The reported incidence is 0.2% of all cardiac tumours. It is estimated that there is only one surgical case annually in Japan. Synovial sarcomas originate from the mesenchymal sites in the heart, mostly pericardium or endocardium. The two types are monophasic (spindle mesenchymal cells only) and biphasic (mesenchymal and epithelioglandular). According to a series of 60 cases of primary cardiac synovial sarcoma, 47.1% of cardiac synovial sarcomas show biphasic growth patterns, with survival rates of approximately 59.9% at 1 year and 29.9% at 5 years. Patients with the biphasic type combined with Ki67 positivity lower than 15 per 10 HPF, as in this case, can expect a prognosis of more than 3–5 years. Additionally, the survival rate of SS18-SSX2 genepositive synovial sarcoma is significantly better than SS18-SSX1 gene fusion type. There are few reports that cardiac tumours induce conduction abnormality. Although direct invasion was not seen in the right atrial conducting system such as Koch’s triangle, a large intra-atrial tumour may have compressed the conductive system and induced atrioventricular block.


Cardiovascular Pathology | 2016

Surgical resection of two independent primary intimal sarcomas in the left atrium.

Motoaki Ohnaka; Masahisa Kyogoku; Hiroyuki Nakajima; Hiroaki Osada; Katsuaki Meshii; Naoki Kanemitsu

Primary intimal sarcoma of the heart is an extremely rare tumor that is known to have a very poor prognosis. We present a case of a 65-year-old man who suffered from deteriorating congestive heart failure due to a severe mitral stenosis caused by a large mobile left atrial tumor. The patient underwent an emergency operation of the tumor in the left atrium. The tumor was attached to the inferior wall of the left atrium. After the resection of the tumor, a second tumor on the interatrial septum, which had not been detected in the preoperative investigation, was discovered and resected. The patient developed acute respiratory failure soon after the operation and succumbed to his illness. The appearance of the main tumor was cauliflower-like, which strongly suggested the possibility of malignancy. Immunohistochemistry revealed that the neoplastic cells were positive for vimentin, desmin, p16, and especially murine double minute 2 (MDM-2). The first tumor was CD34 positive and cdk4 negative, but the second tumor was more anaplastic and CD34 negative and cdk4 positive, which suggests a different origin of the two tumors. The two tumors were diagnosed as intimal sarcomas by MDM-2, which is currently considered a conclusive marker. This is an exceptionally rare case of two simultaneous and possibly independent primary intimal sarcomas in the left atrium.


European Journal of Cardio-Thoracic Surgery | 2014

Reply to Angouras and Sokolis

Masahisa Kyogoku; Hiroaki Osada; Hiroyuki Nakajima

We thank the research team of Dr Angouras for their comments [1] regarding our previous article [2] and really appreciate the opportunity to provide clarifications. As you mentioned in your letter, several articles of yours and other researchers based in Greece describing various types of animal experiments involving the ligation of intercostal arteries to shut down the bloodstream of the vasa vasorum of the upper parts of the aorta strongly encouraged us to emphasize the role of the vasa vasorum as a key factor in aortic dissection. However, according to our research team, there are several important differences between the histological features of our human cases and your animal experiments. In the animal experiments, the bloodstream was completely shut down and the results were the necrosis (or infarction) of the smooth muscle cells (SMCs) in the middle zone of the aortic wall and consequent scar formation. In our human cases, the changes around the dissection area in the aortic media were not necrosis but merely mild degeneration, which we believe to be a phenotypic transformation (from a contractile and elastin secretory type to collagen-acid mucopolysaccharide secretory type) of vascular SMCs. We emphasized this hypothesis in our article [2] and it was confirmed recently by molecular biology studies [3]. Moreover, complete obstruction of the vasa vasorum was rare in our cases (14%). Therefore, such medial changes could not be made by complete obstruction. Obstruction is rare but we found intimal thickening, elastosis and even myomatous proliferation in the media of the vasa vasorum. Those features must be the sequelae of hypertension and angiospasms, which we realized during research work in spontaneously hypertensive rats [4]. Lifelong, mild but repeated or intermittent ischaemia and malnutrition could introduce such transformations as a background to dissection. Then, what is the real trigger? We confirmed that the initial sign of dissection was just on the vasa vasorum itself, where vascular necrosis and extravascular leakage of erythrocytes are present. Hence, the vasa vasorum itself is the starting point of dissection. Dramatic angiospasms or rapid increases and decreases in blood pressure could be the trigger of dissection. More than 60% of our cases had a history of hypertension, and histopathological analyses suggested that >75% were hypertensive. In general, in elderly subjects, the number of hypertensive persons is increased but the number of people suffering from aortic dissection seems to be very low. Hypertension could be the ‘necessary factor’ for aortic dissection but not the ‘sufficient factor’. The question is: what is the other necessary factor? Together with epigenetic factors such as aging, infection, inflammation and nutrition, several genes encoding proteins in SMC contractile units as well as signal proteins in SMCs [3] must be involved in host susceptibility genes as polymorphic genes to lead a phenotypic transformation of SMCs. Further immunohistochemical studies and/or in situ hybridization studies should be carried out to clarify the expression and dynamics of these molecules around the dissection site.


Archives of Dermatology | 2010

A case of intravascular large B-cell lymphoma with atypical clinical manifestations and analysis of CXCL12 and CXCR4 expression.

Saeko Nakajima; Kouichi Ohshima; Masahisa Kyogoku; Yoshiki Miyachi; Kenji Kabashima


Japanese Journal of Cardiovascular Surgery | 2011

A Case of Mitral Valve Plasty without Autologous Pericardium for Active Infective Endocarditis

Atsushi Shimizu; Hiroyuki Nakajima; Hiroaki Osada; Atsushi Nagasawa; Masahisa Kyogoku

Collaboration


Dive into the Masahisa Kyogoku's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge