著者

Yoshihiro Oyama Yudai Kawasaki Kazushi Takahashi

出版者

一般社団法人 情報処理学会

雑誌

Journal of Information Processing (ISSN:18826652)

巻号頁・発行日

vol.23, no.2, pp.132-141, 2015 (Released:2015-03-15)

参考文献数

30

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Many dynamic malware analysis systems based on hypervisors have been proposed. Although they support malware analysis effectively, many of them have a shortcoming that permits the malware to easily recognize the virtualized hardware and change its execution to prevent analysis. We contend that this drawback can be mitigated using a hypervisor that virtualizes the minimum number of hardware accesses. This paper proposes a hypervisor-based mechanism that can function as a building block for dynamic malware analysis systems. The mechanism provides the facility for checkpointing and restoring a guest OS. It is designed for a parapass-through hypervisor, that is, a hypervisor that runs directly on the hardware and does not execute a host OS or an administrative guest OS. The advantage of using a parapass-through hypervisor is that it provides a virtual machine whose hardware configuration and behavior is similar to the underlying physical machine, and hence, it can be stealthier than other hypervisors. We extend the parapass-through hypervisor BitVisor with the proposed mechanism, and demonstrate that the resulting system can successfully checkpoint and restore the states of Linux and Windows OSes. We confirm that hypervisor detectors running on the system cannot identify the virtualized hardware, and determine that they are executing on a physical machine. We also confirm that the system imposes minimal overhead on the execution times of the benchmark programs.

著者

Ryohei Norioka Shinsuke Tobisawa Ryusei Nishigori Tomiko Kuhara Masahide Yazaki Masayoshi Nagao Toshihiro Ohura Yasuyuki Takai Asuka Funai Kazuhito Miyamoto Akihiro Kawata Kazushi Takahashi

出版者

International Research and Cooperation Association for Bio & Socio-Sciences Advancement

雑誌

Intractable & Rare Diseases Research (ISSN:21863644)

巻号頁・発行日

vol.10, no.2, pp.126-130, 2021-05-31 (Released:2021-06-03)

参考文献数

16

被引用文献数

3

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We report a case of saccharopinuria with hyperammonemia and hypercitrullinemia in a Japanese woman who presented with elderly-onset epilepsy, progressive cognitive decline, and gait ataxia. Blood amino acid analysis revealed an increase in citrulline, cystine, and lysine levels, and urine amino acid analysis showed increased citrulline and cystine levels. Urine metabolomics revealed an increased saccharopine level, leading to the definitive diagnosis of saccharopinuria. In western blots of liver biopsy samples, normal citrin levels were observed, suggesting that adult-onset citrullinemia type 2 (CTLN2) was not present. In addition, decreased argininosuccinate synthetase (ASS) levels were observed, and ASS1 gene, a causative gene for citrullinemia type 1 (CTLN1), was analyzed, but no gene mutations were found. Because the causes of hypercitrullinemia were not clear, it might be secondary to saccharopinuria. Muscle biopsy findings of the biceps brachii revealed diminished cytochrome c oxidase (COX) activity, mitochondrial abnormalities on electron microscopy and p62-positive structures in immunohistochemical analyses. Saccharopinuria is generally considered a benign metabolic variant, but our case showed elevated lysine and saccharopine levels causing ornithine circuit damage, mitochondrial dysfunction, and autophagy disorders. This may lead to so far unknown neurological disorders.

著者

Yoshihiro Oyama Yudai Kawasaki Kazushi Takahashi

出版者

一般社団法人情報処理学会

雑誌

情報処理学会論文誌 (ISSN:18827764)

巻号頁・発行日

vol.56, no.3, 2015-03-15

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Many dynamic malware analysis systems based on hypervisors have been proposed. Although they support malware analysis effectively, many of them have a shortcoming that permits the malware to easily recognize the virtualized hardware and change its execution to prevent analysis. We contend that this drawback can be mitigated using a hypervisor that virtualizes the minimum number of hardware accesses. This paper proposes a hypervisor-based mechanism that can function as a building block for dynamic malware analysis systems. The mechanism provides the facility for checkpointing and restoring a guest OS. It is designed for a parapass-through hypervisor, that is, a hypervisor that runs directly on the hardware and does not execute a host OS or an administrative guest OS. The advantage of using a parapass-through hypervisor is that it provides a virtual machine whose hardware configuration and behavior is similar to the underlying physical machine, and hence, it can be stealthier than other hypervisors. We extend the parapass-through hypervisor BitVisor with the proposed mechanism, and demonstrate that the resulting system can successfully checkpoint and restore the states of Linux and Windows OSes. We confirm that hypervisor detectors running on the system cannot identify the virtualized hardware, and determine that they are executing on a physical machine. We also confirm that the system imposes minimal overhead on the execution times of the benchmark programs.------------------------------This is a preprint of an article intended for publication Journal ofInformation Processing(JIP). This preprint should not be cited. Thisarticle should be cited as: Journal of Information Processing Vol.23(2015) No.2 (online)DOI http://dx.doi.org/10.2197/ipsjjip.23.132------------------------------Many dynamic malware analysis systems based on hypervisors have been proposed. Although they support malware analysis effectively, many of them have a shortcoming that permits the malware to easily recognize the virtualized hardware and change its execution to prevent analysis. We contend that this drawback can be mitigated using a hypervisor that virtualizes the minimum number of hardware accesses. This paper proposes a hypervisor-based mechanism that can function as a building block for dynamic malware analysis systems. The mechanism provides the facility for checkpointing and restoring a guest OS. It is designed for a parapass-through hypervisor, that is, a hypervisor that runs directly on the hardware and does not execute a host OS or an administrative guest OS. The advantage of using a parapass-through hypervisor is that it provides a virtual machine whose hardware configuration and behavior is similar to the underlying physical machine, and hence, it can be stealthier than other hypervisors. We extend the parapass-through hypervisor BitVisor with the proposed mechanism, and demonstrate that the resulting system can successfully checkpoint and restore the states of Linux and Windows OSes. We confirm that hypervisor detectors running on the system cannot identify the virtualized hardware, and determine that they are executing on a physical machine. We also confirm that the system imposes minimal overhead on the execution times of the benchmark programs.------------------------------This is a preprint of an article intended for publication Journal ofInformation Processing(JIP). This preprint should not be cited. Thisarticle should be cited as: Journal of Information Processing Vol.23(2015) No.2 (online)DOI http://dx.doi.org/10.2197/ipsjjip.23.132------------------------------

著者

Azusa Orihara Natsuki Miyakoshi Yoko Sunami Hideki Kimura Yasuhiro Nakata Takashi Komori Jun Sone Kazushi Takahashi

出版者

The Japanese Society of Internal Medicine

雑誌

Internal Medicine (ISSN:09182918)

巻号頁・発行日

pp.0156-22, (Released:2022-10-26)

参考文献数

14

被引用文献数

1

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A 75-year-old man presented with headache and disturbance of consciousness. Magnetic resonance imaging revealed edema localized mainly in the cortex and linear contrast enhancement. A brain biopsy revealed numerous astrocytes with inclusion, and genetic testing demonstrated prolonged GGC repeats in NOTCH2NLC. The present case provided two novel insights into the mechanism underlying encephalopathy associated with neuronal intranuclear inclusion disease. First, the histological findings at a site with contrast enhancement on magnetic resonance imaging did not demonstrate any organic association, such as the presence of inflammation or ischemic changes. Second, the imaging and cerebrospinal fluid findings demonstrated increased cerebral blood flow and opening of the blood-brain barrier, indicating the cause of the cerebral swelling.

著者

Kazushi Takahashi Hirotaka Mutsuzaki Yuki Mataki Kenichi Yoshikawa Mayumi Matsuda Keiko Enomoto Kumiko Sano Aoi Kubota Masafumi Mizukami Nobuaki Iwasaki Masashi Yamazaki

出版者

The Society of Physical Therapy Science

雑誌

Journal of Physical Therapy Science (ISSN:09155287)

巻号頁・発行日

vol.30, no.8, pp.1009-1013, 2018 (Released:2018-07-24)

参考文献数

21

被引用文献数

16

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[Purpose] This study aimed to determine the safety and immediate effect of a single training session with the Hybrid Assistive Limb (CYBERDYNE) on walking ability in patients with cerebral palsy. [Participants and Methods] This study included 20 patients with cerebral palsy (15 males, 5 females, mean age 15.0 ± 6.3 years; 19 with spastic cerebral palsy, 1 with athetoid cerebral palsy; Gross Motor Function Classification System level I: 4, II: 3, III: 9, and IV: 4). Participants completed a single 20-minute gait training session using the Hybrid Assistive Limb. The safety and immediate effect were evaluated. The immediate outcomes were gait speed and mean step length, and cadence before and after training. [Results] Two participants were excluded because they were not tall enough to use the Hybrid Assistive Limb. Eighteen participants performed the training. There were no serious adverse events during the training. Since 14 participants were able to walk on their own, walking evaluations were performed before and after training. Statistically significant improvements were observed in gait speed and mean step length. [Conclusion] Gait training using the Hybrid Assistive Limb is safe for patients with cerebral palsy and can produce immediate effects on walking ability in ambulatory patients with cerebral palsy.