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Featured researches published by Katsumi Hoya.


Surgical Oncology-oxford | 2011

A case of multiple brain metastases of uterine leiomyosarcoma with a literature review

So Yamada; Shoko M. Yamada; Hiroshi Nakaguchi; Mineko Murakami; Katsumi Hoya; Akira Matsuno

Brain metastasis from uterine leiomyosarcoma is extremely rare, and prognostically alarming despite various treatments. The authors report a case of multiple brain metastases from uterine leiomyosarcoma who took a favorable course after tumor resection and γ-knife treatment. A 50-year-old woman with a history of hysterectomy for uterine leiomyosarcoma two years earlier, presented with a recent onset of headaches and vomiting. Multiple cerebral lesions were found by magnetic resonance imaging (MRI). The Karnofsky performance scale (KPS) was 40 with left hemiparesis and cerebellar ataxia. She was treated by resection of the left occipital and cerebellar tumors, followed by γ-knife irradiation of the residual tumors. KPS was 70 at her discharge from the hospital. MRI failed to show recurrence of the intracranial lesions 6 months after irradiation. She remained at home until she died from massive intra-abdominal bleeding. This is the first case with multiple brain metastases from uterine leiomyosarcoma, who survived with remarkable neurological improvement for 12 months. No comparable survival has been reported in the literature. It is evident that surgical resection and additional γ-knife irradiation contributed to early neurological recovery.


Clinical Neurology and Neurosurgery | 2012

A simple and consistent technique for ventricular catheter insertion using a tripod.

Shoko M. Yamada; So Yamada; Yoshiaki Goto; Hiroshi Nakaguchi; Mineko Murakami; Katsumi Hoya; Akira Matsuno

OBJECTIVE For long-term preservation of ventriculo-peritoneal (VP) shunt function, it is essential to place the ventricular catheter tip above the foramen of Monro. But the free-hand technique for ventricular catheter passage is not consistent. METHODS Supposing that a convex of skull matches to a sphere, in which the foramen of Monro is the center, a perpendicular direction from the surface of the sphere to inside always directs toward the center. The authors identified the range of skull where corresponded to the sphere by magnetic resonance imaging assessment and utilized tripod to achieve exactly perpendicular insertion of ventricular catheter. And an optimal length of catheter insertion was investigated by navigation system. RESULTS The anterior-posterior range of the spherical portion was from coronal suture to 20mm anterior, and the lateral range of it was between 15 and 35mm lateral from sagittal suture. The optimal catheter length for insertion was between 55 and 58mm from the brain surface. Ideal placement of a ventricular catheter tip was achieved in more than 90% of cases (31/34) with this technique. CONCLUSION Tripod-guided ventricular catheter insertion is a simple and reliable method for VP shunt at any angle of head-rotation.


Journal of Medical Case Reports | 2012

Tumefactive multiple sclerosis requiring emergent biopsy and histological investigation to confirm the diagnosis: a case report

So Yamada; Shoko M. Yamada; Hiroshi Nakaguchi; Mineko Murakami; Katsumi Hoya; Akira Matsuno; Kazuto Yamazaki; Yasuo Ishida

IntroductionTumefactive multiple sclerosis is a demyelinating disease that demonstrates tumor-like features on magnetic resonance imaging. Although diagnostic challenges without biopsy have been tried by employing radiological studies and cerebrospinal fluid examinations, histological investigation is still necessary for certain diagnosis in some complicated cases.Case presentationA 37-year-old Asian man complaining of mild left leg motor weakness visited our clinic. Magnetic resonance imaging demonstrated high-signal lesions in bilateral occipital forceps majors, the left caudate head, and the left semicentral ovale on fluid-attenuated inversion recovery and T2-weighted imaging, and these lesions were enhanced by gadolinium-dimeglumin. Tumefactive multiple sclerosis was suspected because the enhancement indistinctly extended along the corpus callosum on magnetic resonance imaging and scintigraphy showed a low malignancy of the lesions. But oligoclonal bands were not detected in cerebrospinal fluid. In a few days, his symptoms fulminantly deteriorated with mental confusion and left hemiparesis, and steroid pulse therapy was performed. In spite of the treatment, follow-up magnetic resonance imaging showed enlargement of the lesions. Therefore, emergent biopsy was performed and finally led to the diagnosis of demyelinating disease. The enhanced lesion on magnetic resonance imaging disappeared after one month of prednisolone treatment, but mild disorientation and left hemiparesis remained as sequelae.ConclusionsFulminant aggravation of the disease can cause irreversible neurological deficits. Thus, an early decision to perform a biopsy is necessary for exact diagnosis and appropriate treatment if radiological studies and cerebrospinal fluid examinations cannot rule out the possibility of brain tumors.


Medical Molecular Morphology | 2014

Molecular status of pituitary carcinoma and atypical adenoma that contributes the effectiveness of temozolomide

Akira Matsuno; Mineko Murakami; Katsumi Hoya; Shoko M. Yamada; Shinya Miyamoto; So Yamada; Jae-Hyun Son; Hajime Nishido; Fuyuaki Ide; Hiroshi Nagashima; Mutsumi Sugaya; Toshio Hirohata; Akiko Mizutani; Yudo Ishii; Shigeyuki Tahara; Akira Teramoto; R. Yoshiyuki Osamura

There have been several reports of temozolomide (TMZ) treatment of pituitary carcinomas and atypical adenomas. O6-methyl-guanine-DNA methyltransferase is not the sole molecule determining the sensitivity to TMZ in pituitary carcinomas and atypical adenomas. The Japan Society of Hypothalamic and Pituitary Tumors study suggests that MSH6, one of mismatch repair pathway enzyme, fulfills a contributory role to the efficacy of TMZ treatment for pituitary carcinomas and atypical adenomas. The preserved MSH6 function might be essential for the responsiveness to TMZ treatment in pituitary carcinomas and atypical adenomas.


Clinical Journal of Sport Medicine | 2014

Vertebral artery dissection caused by swinging a golf club: case report and literature review.

Shoko M. Yamada; Yoshiaki Goto; Mineko Murakami; Katsumi Hoya; Akira Matsuno

Vertebral artery (VA) dissection caused by swinging a golf club is extremely rare, and the mechanism of the dissection has not been elucidated. A 39-year-old man suddenly felt sharp neck pain and dizziness when he swung a driver while playing golf and visited our clinic. Imaging studies showed acute right cerebellar infarction and complete occlusion of the right VA at the C2 (axis) level. After 1 month of 100 mg aspirin treatment, the occluded right VA was completely recanalized and the patient became totally asymptomatic. Professional golfers look at the position of the ball on the ground or tee until completion of their follow-through. However, some amateur golfers look in the direction that the ball travels at the beginning of their follow-through. It is hypothesized that this rapid disproportionate head rotation produces VA elongation and distortion, mainly at the C2 level, causing stenosis or occlusion of the artery.


Acta Histochemica Et Cytochemica | 2013

Clinicopathological and molecular histochemical review of skull base metastasis from differentiated thyroid carcinoma.

Akira Matsuno; Mineko Murakami; Katsumi Hoya; Shoko M. Yamada; Shinya Miyamoto; So Yamada; Jae-Hyun Son; Hajime Nishido; Fuyuaki Ide; Hiroshi Nagashima; Mutsumi Sugaya; Toshio Hirohata; Akiko Mizutani; Yudo Ishii; Shigeyuki Tahara; Akira Teramoto; R. Yoshiyuki Osamura; Kazuto Yamazaki; Yasuo Ishida

Skull base metastasis from differentiated thyroid carcinoma including follicular thyroid carcinoma (FTC) and papillary thyroid carcinoma (PTC) is a rare clinical entity. Eighteen FTC cases and 10 PTC cases showing skull base metastasis have been reported. The most common symptom of skull base metastasis from FTC and PTC is cranial nerve dysfunction. Bone destruction and local invasion to the surrounding soft tissues are common on radiological imaging. Skull base metastases can be the initial clinical presentation of FTC and PTC in the presence of silent primary sites. The possibility of skull base metastasis from FTC and PTC should be considered in patients with the clinical symptoms of cranial nerve dysfunction and radiological findings of bone destruction. A variety of genetic alterations in thyroid tumors have been identified to have a fundamental role in their tumorigenesis. Molecular histochemical studies are useful for elucidating the histopathological features of thyroid carcinoma. Recent molecular findings may provide novel molecular-based treatment strategies for thyroid carcinoma.


Molecules | 2011

Molecular Morphology of Pituitary Cells, from Conventional Immunohistochemistry to Fluorescein Imaging

Akira Matsuno; Akiko Mizutani; Koji Takano; So Yamada; Shoko M. Yamada; Hiroshi Nakaguchi; Katsumi Hoya; Mineko Murakami; Masato Takeuchi; Mutsumi Sugaya; Johbu Itoh; Susumu Takekoshi; Robert Yoshiyuki Osamura

In situ hybridization (ISH) at the electron microscopic (EM) level is essential for elucidating the intracellular distribution and role of mRNA in protein synthesis. EM-ISH is considered to be an important tool for clarifying the intracellular localization of mRNA and the exact site of pituitary hormone synthesis on the rough endoplasmic reticulum. A combined ISH and immunohistochemistry (IHC) under EM (EM-ISH&IHC) approach has sufficient ultrastructural resolution, and provides two-dimensional images of the subcellular localization of pituitary hormone and its mRNA in a pituitary cell. The advantages of semiconductor nanocrystals (quantum dots, Qdots) and confocal laser scanning microscopy (CLSM) enable us to obtain three-dimensional images of the subcellular localization of pituitary hormone and its mRNA. Both EM-ISH&IHC and ISH & IHC using Qdots and CLSM are useful for understanding the relationships between protein and mRNA simultaneously in two or three dimensions. CLSM observation of rab3B and SNARE proteins such as SNAP-25 and syntaxin has revealed that both rab3B and SNARE system proteins play important roles and work together as the exocytotic machinery in anterior pituitary cells. Another important issue is the intracellular transport and secretion of pituitary hormone. We have developed an experimental pituitary cell line, GH3 cell, which has growth hormone (GH) linked to enhanced yellow fluorescein protein (EYFP). This stable GH3 cell secretes GH linked to EYFP upon stimulation by Ca2+ influx or Ca2+ release from storage. This GH3 cell line is useful for the real-time visualization of the intracellular transport and secretion of GH. These three methods from conventional immunohistochemistry and fluorescein imaging allow us to consecutively visualize the process of transcription, translation, transport and secretion of anterior pituitary hormone.


BMC Neurology | 2014

Subarachnoid hemorrhage secondary to a ruptured middle cerebral aneurysm in a patient with osteogenesis imperfecta: a case report

Toshio Hirohata; Satoru Miyawaki; Akiko Mizutani; Takayuki Iwakami; So Yamada; Hajime Nishido; Yasutaka Suzuki; Shinya Miyamoto; Katsumi Hoya; Mineko Murakami; Akira Matsuno

BackgroundOsteogenesis imperfecta (OI) is a heterogeneous group of inherited disorders that occur owing to the abnormalities in type 1 collagen, and is characterized by increased bone fragility and other extraskeletal manifestations. We report the case of a patient who was diagnosed with OI following subarachnoid hemorrhage (SAH) secondary to a ruptured saccular intracranial aneurysm (IA).Case PresentationA 37-year-old woman was referred to our hospital because of sudden headache and vomiting. She was diagnosed with SAH (World Federation of Neurosurgical Society grade 2) owing to an aneurysm of the middle cerebral artery. She then underwent surgical clipping of the aneurysm successfully. She had blue sclerae, a history of several fractures of the extremities, and a family history of bone fragility and blue sclerae in her son. According to these findings, she was diagnosed with OI type 1. We performed genetic analysis for a single nucleotide G/C polymorphism (SNP) of exon 28 of the gene encoding for alpha-2 polypeptide of collagen 1, which is a potential risk factor for IA. However, this SNP was not detected in this patient or in five normal control subjects. Other genetic analyses did not reveal any mutations of the COL1A1 or COL1A2 gene. The cerebrovascular system is less frequently involved in OI. OI is associated with increased vascular weakness owing to collagen deficiency in and around the blood vessels. SAH secondary to a ruptured IA with OI has been reported in only six cases.ConclusionThe patient followed a good clinical course after surgery. It remains controversial whether IAs are caused by OI or IAs are coincidentally complicated with OI.


Case reports in neurological medicine | 2012

Endoscopic Extracapsular Removal of Pituitary Adenoma: The Importance of Pretreatment of an Adjacent Unruptured Internal Carotid Artery Aneurysm

So Yamada; Shoko M. Yamada; Toshio Hirohata; Yudo Ishii; Katsumi Hoya; Mineko Murakami; Akira Matsuno

The presence of an intracranial aneurysm together with a pituitary adenoma presents tremendous risk of subarachnoid hemorrhage, during transsphenoidal surgery, particularly when the aneurysm lies near the operative field. A left supraclinoid internal carotid artery aneurysm and a clinically nonfunctioning pituitary adenoma coexisted in a 57-year-old woman. Initially, the aneurysm was treated by endovascular coil placement, and then the patient underwent pseudocapsule-based extracapsular resection of the pituitary tumor via a transnasal transsphenoidal endoscopic approach. Pseudocapsule-based extracapsular total resection was safely performed, because of the extirpated risk of rupture of the coil-treated aneurysm. Recently, transsphenoidal pseudocapsule-based extracapsular resection approach for pituitary adenomas provides a more effective and safe alternative compared to the traditional intracapsular one because of its higher tumor removal and remission rates and lower recurrence rate. Compared with conventional subcapsular removal, pseudocapsule-based extracapsular resection has more risks of aneurysmal rupture that is located adjacent to pituitary adenoma. Thus, in a patient having a cerebral aneurysm with the proximity to the operative field, the cerebral aneurysm should be first treated with endovascular coil placement or direct surgical procedure; subsequently, pseudocapsule-based extracapsular resection of the pituitary tumor via a transnasal transsphenoidal endoscopic approach should be performed.


Medical Molecular Morphology | 2011

Functional molecular morphology of anterior pituitary cells, from hormone production to intracellular transport and secretion

Akira Matsuno; Akiko Mizutani; Koji Takano; So Yamada; Shoko M. Yamada; Hiroshi Nakaguchi; Katsumi Hoya; Mineko Murakami; Masato Takeuchi; Mutsumi Sugaya; Johbu Itoh; Susumu Takekoshi; R. Yoshiyuki Osamura

Combined in situ hybridization (ISH) and immunohistochemistry (IHC) under electron microscopy (EM-ISH & IHC) has sufficient ultrastructural resolution to provide two-dimensional images of subcellular localization of pituitary hormone and its mRNA in a pituitary cell. The advantages of semiconductor nanocrystals (Quantum dots; Qdots) and confocal laser scanning microscopy (CLSM) enable us to obtain three-dimensional images of the subcellular localization of pituitary hormone and its mRNA. Both EM-ISH & IHC and ISH & IHC using Qdots and CLSM are useful for understanding the relationship between protein and mRNA simultaneously in two or three dimensions. CLSM observation of rab3B and SNARE proteins such as SNAP-25 and syntaxin revealed that both rab3B and SNARE system proteins play an important role and work together as the exocytotic machinery in anterior pituitary cells. Another important issue is the intracellular transport and secretion of pituitary hormone. An experimental pituitary cell line, the GH3 cell, in which growth hormone (GH) is linked to enhanced yellow fluorescein protein (EYFP), has been developed. This stable GH3 cell secretes GH linked to EYFP upon being stimulated by Ca2+ influx or Ca2+ release from storage. This GH3 cell is useful for real-time visualization of the intracellular transport and secretion of GH. These three methods enable us to visualize consecutively the processes of transcription, translation, transport, and secretion of pituitary hormone.

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Akiko Mizutani

Teikyo Heisei University

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