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Life Sciences | 1991

Lack of alcohol dehydrogenase isoenzyme activities in the stomach of Japanese subjects

Enrique Baraona; Akira Yokoyama; Hiromasa Ishii; Rolando Hernández-Muñoz; Toshikazu Takagi; Masaharu Tsuchiya; Charles S. Lieber

Alcohol dehydrogenase (ADH) isoenzymes different from those of the liver were shown to be present in the human gastric mucosa. Two ADH activity bands present in the gastric mucosa of surgical specimens from all 7 black and 11 white Americans studied were absent in 14 and barely detectable in 3 of 21 Japanese subjects evaluated. Similar ethnic differences pertained to both genders and were independent of the gastric pathology. The mobility of these bands on starch gel electrophoresis corresponded to those recently reported and named mu-ADH or sigma-ADH. The absence of these bands was associated with a 70% decreased capacity to reduce m-nitrobenzaldehyde, a preferred substrate for sigma-ADH, suggesting that the bands missing from the Japanese stomachs comprise this isoenzyme.


Neuroscience Letters | 2004

Association of aldehyde dehydrogenase-2 polymorphism with alcoholic polyneuropathy in humans

Toshihiro Masaki; Hitoshi Mochizuki; Sachio Matsushita; Akira Yokoyama; Keiko Kamakura; Susumu Higuchi

Persons who have the Glu-487-->Lys mutation (single nucleotide polymorphism) of the aldehyde dehydrogenase-2 (ALDH2) gene have less ability to metabolize the alcohol breakdown product acetaldehyde. In order to clarify whether acetaldehyde is associated with the pathogenesis of alcoholic polyneuropathy, we compared nerve conduction data as well as clinical signs and symptoms of neuropathy between alcoholics with ALDH2*2 (Lys-487) heterozygotes and those with ALDH2*1 (Glu-487) homozygotes. Alcoholics with ALDH2*2 heterozygotes showed significantly lower sensory nerve action potential amplitudes of the sural and median nerves than those with ALDH2*1 homozygotes, suggesting that the accumulation of acetaldehyde due to ALDH2 inactivity is associated with alcoholic polyneuropathy.


Alcoholism: Clinical and Experimental Research | 2010

Effect of a Comprehensive Lifestyle Modification Program on the Bone Density of Male Heavy Drinkers

Toshifumi Matsui; Akira Yokoyama; Sachio Matsushita; Ryuichi Ogawa; Shuka Mori; Emiko Hayashi; Sungwon Roh; Susumu Higuchi; Hiroyuki Arai; Katsuya Maruyama

BACKGROUNDnHeavy alcohol drinking is implicated in osteoporosis. Although abstinence is rapidly followed by a restoration of osteoblastic activity, little is known about the contributions of alcohol-related factors or the effectiveness of a lifestyle modification program (LMP) on bone density.nnnMETHODSnWe conducted a study of 138 male alcoholic patients to investigate whether drinking history and concurrent factors were associated with the bone density of the calcaneus. A 2.5-months LMP in an institutionalized setting was completed by 20 of them, and its effect on bone density, serum parathyroid hormone (PTH), and 1.25-(OH)(2) vitamin D levels were assessed.nnnRESULTSnThe patients had a high prevalence of daytime drinking (93.5%), continuous drinking (84.1%), and current smoking (82.0%) with mean duration of alcohol abuse of 30.0 +/- 12.8 years. The patients had lower bone density than a reference control group (Z-scores: -0.45 +/- 1.02). Multiple stepwise regression analysis identified age, poor activities of daily living (ADL), continuous drinking, absence of liver cirrhosis, depression, and dementia as determinants of low bone density. The bone density of the 20 participants in the LMP improved 2.3% (p = 0.0003) with a more ameliorating effect on bone density than a conventional abstinence therapy (p = 0.014 for interventional effect). The upper normal range of PTH levels at baseline were significantly decreased, and 1.25-(OH)(2) vitamin D levels also had a trend toward decrease during the abstinence.nnnCONCLUSIONSnAlcoholic patients may have many complications such as poor ADL and dementia, which are independently associated with decreased bone density. The results of this study support the idea that comprehensive approach to lifestyle factors to minimize risk of osteoporosis is the best way to improve bone density.


Alcoholism: Clinical and Experimental Research | 2008

Elevated Cerebrospinal Fluid Tau Protein Levels in Wernicke’s Encephalopathy

Sachio Matsushita; Tomohiro Miyakawa; Hitoshi Maesato; Toshifumi Matsui; Akira Yokoyama; Hiroyuki Arai; Susumu Higuchi

OBJECTIVEnLimited neuronal cell loss is seen in the neuropathology of Wernickes encephalopathy (WE), but the extent of neuronal damage has not been well studied. Moreover, there is still a debate as to whether alcohol itself causes brain damage in humans. Although, it is difficult to examine the extent of neuronal damage in living patients, recent studies have revealed that total tau protein levels in the cerebrospinal fluid (CSF) reflect the rate of neuronal degeneration. Therefore, we hypothesized that the elevated CSF total tau in patients with WE was due to neuronal damage and thus we examined CSF total tau protein in patients with WE, as well as in those with alcohol withdrawal delirium (WD) and Korsakoff syndrome (KS). We also examined CSF total tau in nonalcohol dependent patients with Alzheimers disease (AD) as a disease control.nnnMETHODSnCSF samples were obtained from 13 acute WE patients with alcohol dependence, 9 WD patients with alcohol dependence and 16 KS patients with alcohol dependence, and from 20 nonalcohol dependent AD patients. CSF was also obtained from 10 of the WE patients after their disease had progressed to the chronic stage. CSF tau protein levels in all samples were determined by sandwich enzyme-linked immunosorbent assay. Tau phosphorylated at threonine 181 (p-tau(181)) and amyloid beta-protein ending at amino acid 42 (A beta 42) in CSF were also determined for comparison between acute WE with AD.nnnRESULTSnTotal tau was significantly elevated in acute WE and decreased on long-term follow-up, but was not elevated in WD or KS. The patterns of p-tau(181) and A beta 42 differed between acute WE and AD.nnnCONCLUSIONSnIntense neuronal cell death occurs transiently in WE, and the mechanism differs from that in AD. Neuronal damage is generally unaccompanied in WD. These results suggest that CSF total tau is a useful biological marker for WE.


Gastroenterologia Japonica | 1993

Fatal herpes simplex hepatitis type 2 in a post-thymectomized adult

Naoko Takebe; Akira Yokoyama; Yoshikiyo Akasaka; Hiromasa Ishii; Shingo Miyaguchi; Tetsutaro Sata; Toshifumi Hibi; Masaya Oda; Jun-ichi Hata; Masaharu Tsuchiya

SummaryThe authors report an unusual case of herpes simplex type 2 (HSV) hepatitis which presented as part of a systemic HSV infection accompanied by disseminated intravascular coagulation (DIC). The patient was a 49-year-old Japanese male who three months prior to admission underwent surgical resection of his thymus for an invasive thymoma. Postoperatively, he received a course of chemotherapy which included prednisone, cyclophosphamide, vincristine, and pinorubicin. After discharge from the hospital, he was put on a maintenance dosage of prednisone and cyclophosphamide. Two weeks prior to this admission, the patient developed rhinorrhea, chills and general fatigue. Routine follow-up laboratory tests revealed markedly elevated liver enzymes which led to his immediate hospitalization. The tentative diagnosis on admission was fulminant hepatitis with DIC. The patient’s condition steadily worsened during his hospitalization and acyclovir was initiated on the 4th hospital day due to the possibility of HSV hepatitis. He died on the same day. Histopathology performed on the liver at autopsy revealed hepatic inclusion bodies of HSV with positive immunohistochemical detection of the HSV type 2 antigen. Our case is the first report of HSV hepatitis associated with the removal of the thymus secondary to thymoma. It supports previous observations of disseminated HSV infection being prevalent in those patients with disorders of cell mediated immunity.


Journal of the American Geriatrics Society | 2010

CHANGES IN THE SERUM BONE METABOLISM MARKERS OF ELDERLY ALCOHOLICS DURING ABSTINENCE

Toshifumi Matsui; Akira Yokoyama; Sachio Matsushita; Shuka Mori; Hiroyuki Arai; Susumu Higuchi; Katsuya Maruyama

ACKNOWLEDGMENTS Conflict of Interest: The editor in chief has reviewed the conflict of interest checklist provided by the authors and has determined that the authors have no financial or any other kind of personal conflicts with this paper. Author Contributions: All authors contributed to the conception of the description and in the writing of this case report and have approved the manuscript in its present form. Sponsor’s Role: None.


Alcoholism: Clinical and Experimental Research | 1991

Impaired autonomic nervous system in alcoholics assessed by heart rate variation

Akira Yokoyama; Toshikazu Takagi; Hiromasa Ishii; Taro Muramatsu; Junichiro Akai; Shinzo Kato; Shingo Hori; Katsuya Maruyama; Hiroaki Kono; Masaharu Tsuchiya


Alcoholism: Clinical and Experimental Research | 1992

Prolonged QT interval in alcoholic autonomic nervous dysfunction.

Akira Yokoyama; Hiromasa Ishii; Toshikazu Takagi; Shingo Hori; Sachio Matsushita; Shohei Onishi; Fuminori Katsukawa; Izumi Takei; Shinzo Kato; Katsuya Maruyama; Masaharu Tsuchiya


Archive | 2001

Alcohol and Cancer of the Aerodigestive Tract

Hiromasa Ishii; Shinzo Kato; Akira Yokoyama; Katsuya Maruyama


Archive | 2014

Enzymatic Aspects of Alcoholism-ADH and ALDH

Mitsuru Kimura; Akira Yokoyama; Sachio Matsushita; Susumu Higuchi

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Sachio Matsushita

National Institute for Health and Welfare

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Susumu Higuchi

National Institute for Health and Welfare

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