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Satoshi Yamaguchi

Publications and source records attributed to Satoshi Yamaguchi.

67 records · Page 4Linked to original sources
PubMed2002

Prevalence of dementia and dementing diseases in Japan: the Tajiri project.

BACKGROUND: Vascular dementia (VaD) has been considered to be more prevalent than Alzheimer disease in Japan. However, this might be the result of overdiagnosis stemming from some problematic diagnosis of VaD or of the frequent use of magnetic resonance imaging to detect cerebrovascular disease in older adults. OBJECTIVES: We investigated the prevalence of dementia and the ratios of dementing diseases. The effects of different criteria for VaD (DSM-IV, Alzheimer's Disease Diagnostic and Treatment Centers [ADDTC], and National Institute of Neurological Disorders and Stroke and the Association Internationale pour la Recherche et l'Enseignement en Neurosciences [NINDS-AIREN]) were considered. Hippocampal atrophy and vascular contribution to dementia were evaluated using magnetic resonance imaging findings. METHODS: We targeted all residents 65 years and older (n = 3207) in Tajiri, Japan, and examined 1654 (participant group 1). Of these, 564 (participant group 2) were randomly selected, and 497 underwent magnetic resonance imaging and diagnosis of dementing diseases. RESULTS: We found the overall prevalence of dementia to be 8.5% (141/1654) in participant group 1. Of these, 21 (14.9%) had a history of stroke. Of the 113 participants who had a history of stroke independent of dementia, 18.6% (21/113) were demented. For participant group 2 (n = 497), 32 were demented. The ratio among the dementia for probable VaD based on the NINDS-AIREN criteria was 18.8% (6/32), whereas that for ischemic vascular dementia was 31.3% (10/32) according to the ADDTC criteria. CONCLUSION: We confirmed the overall prevalence of dementia in adults 65 years and older to be 8.5%. We found that VaD was not a common disorder according to the NINDS-AIREN criteria. Rather, the condition of possible Alzheimer disease with cerebrovascular disease was more common.

Aged↗
PubMed2002

Impaction of a shrapnel splinter in the common bile duct after migrating from the right thoracic cavity: report of a case.

Biliary obstruction is rarely caused by a foreign body. This report describes the case of a 60-year-old Japanese man with jaundice caused by an impacted shrapnel splinter in the common bile duct (CBD) that had migrated from the right thoracic cavity 36 years after initial injury. Biochemical data showed a total bilirubin level of 4.2 mg/dl with a direct bilirubin level of 3.1mg/dl, an alanine aminotransferase level of 24IU/l, and an alkaline phosphatase level of 18.5KA units. It was serially documented that the shrapnel had migrated toward the diaphragm, then burrowed into the liver, settling in the CBD, and causing obstructive jaundice. Choledochotomy and T-tube drainage was performed and the postoperative course was uneventful. To our knowledge, this is the first case report of this type of occurrence in the Japanese literature. Although there are few reports of combat injury in Japan, this diagnosis should be considered in the evaluation of any patient with jaundice who has suffered a previous chest wound involving a foreign body.

Cholestasis, Extrahepatic↗
PubMed2002

An unusual perforation of the colon: report of two cases.

We herein present two cases of a colorectal perforation due to uncommon reasons. First, we treated a 45-year-old woman for a stercoral perforation of the sigmoid colon. The pathognomonic etiology was a barium fecaloma originating from an upper gastrointestinal series 9 months before admission. The second case was a 46-year-old woman who was admitted with a perforation of the transverse colon. She had experienced perforations of the sigmoid colon at 32 years of age and of the rectum at 44 years of age, respectively. The second and third conditions were diagnosed to be idiopathic, and were histologically proven by an abrupt obliteration and a thinness of the colonic wall with some infiltration of inflammatory cells. The first condition, however, was most likely a stercoral perforation. The postoperative course of these patients was uneventful, and both are doing well at this writing.

Colonic Diseases↗
PubMed2002

A study of micturition inducing sites in the periaqueductal gray of the mesencephalon.

PURPOSE: The mesencephalon, especially the periaqueductal gray, is believed to integrate specific movement patterns of the somatic and autonomic nervous system, including those of vocalization, defensive behaviors and others. Fiber communications exist between the periaqueductal gray and the pontine micturition center, and many nerve fibers ascending from the sacral spinal cord project to the periaqueductal gray. We examined whether the mesencephalon is involved in micturition function using microstimulation and a neurotracer. MATERIALS AND METHODS: We decerebrated 28 adult cats under general anesthesia. An electrode that can be used for microinjection was positioned in stereotaxic fashion in the mesencephalon and pons. Subsequently electrical stimulation and chemical stimulation with DL-homocysteine acid were applied to search for micturition inducing sites. Blood pressure and respiration were monitored simultaneously. We also performed electrical microstimulation of pontine micturition center. The neurotracer 5% Fluoro-Gold (Denver, Colorado) was injected into these sites to identify neural pathways between the mesencephalon and pons. The brainstem was removed after 10 hours and the mesencephalon was examined by fluorescence microscopy. RESULTS: Bladder contraction was provoked by electrical and chemical stimulation applied mainly at the ventrolateral side of the periaqueductal gray. Blood pressure increased simultaneously with bladder contraction after periaqueductal gray stimulation. Neurotracer injected into the pontine micturition center was found mainly on the ventrolateral side of the periaqueductal gray, in agreement with the sites where micturition was provoked by microstimulation. CONCLUSIONS: Nerve cells on the ventrolateral side of the periaqueductal gray have neural communications with the pontine micturition center bilaterally and they regulate micturition.

Animals↗
PubMed2002

Crossed aphasia: an analysis of the symptoms, their frequency, and a comparison with left-hemisphere aphasia symptomatology.

This study presents a thorough analysis of published crossed aphasia (CA) cases, including for the first time the cases published in Japanese. The frequency of specific symptoms was determined, and symptomatology differences based on gender, familial sinistrality, and CA subtype were investigated. Results suggested that the CA population is comparable to the left-hemisphere patient population. However, male were significantly more likely than female CA subjects to show a positive history of familial sinistrality. Typical right-hemisphere (i.e., nonlanguage-dominant) symptoms were frequent but rarely carefully reported or assessed. Results are compared with previous CA reviews and left-hemisphere aphasia. Suggestions for a more systematic assessment of the CA symptomatology are presented.

Adult↗
PubMed2002

Calcium oxalate monohydrate crystal binding substance produced from Madin-Darby canine kidney cells.

BACKGROUND: The interaction between kidney urothelium and crystals is a critical event in the growth of renal calculi. When studying calcium oxalate monohydrate (COM) crystal binding to Madin-Darby canine kidney (MDCK) cells in culture, we observed that crystals also attached to areas on the coverslips devoid of cells. This phenomenon could be the result of substances produced by the cells that adhere to the glass and subsequently bind COM crystals. We investigated the characteristics of this COM binding substance. METHODS: Media was collected from cultures of MDCK cells (conditioned media) and proteins were separated by high performance liquid chromatography. The molecular weights and purity of isolated proteins were determined by polyacrylamide gel electrophoresis. The conditioned media and each separated fraction were applied to glass and to MDCK cells and COM-binding ability determined using 14C-labeled crystals. The binding of radio-labelled calcium oxalate dihydrate, brushite, uric acid, and apatite to coverslips were also studied. RESULTS: Fourteen times more COM bound to coverslips incubated with conditioned media than those with control media. The molecular weight of the protein bound to the glass was determined to be 200 kDa. The COM crystals binding to this protein was 1.5 micro g/ng. Other crystals bound to a lesser extent. The incubation of cells with this protein inhibited COM binding by 39%. CONCLUSION: The MDCK cells produce a 200-kDa protein that has a high binding affinity for COM crystals. This protein binds to glass and is responsible for crystal binding to areas devoid of cells. This protein also has an inhibitory effect on COM binding to MDCK cells in culture.

Animals↗
PubMed2002

Intradiploic arachnoid cyst identified by diffusion-weighted magnetic resonance imaging--case report.

A 72-year-old woman presented with an intradiploic arachnoid cyst in the occipital intradiploic space which was found incidentally by magnetic resonance (MR) imaging. Computed tomography revealed a widened diploic space and thinning of the inner and outer tables of the occipital bone. The cyst appeared as isointense to the cerebrospinal fluid on both T1- and T2-weighted images. The differential diagnosis of intradiploic epidermoid cyst could be excluded because the lesion was low intensity on diffusion-weighted MR images. Arachnoid cyst is a benign lesion, so exploratory surgery should be avoided unless the cyst is symptomatic. Diffusion-weighted MR imaging is an effective modality to distinguish diploic epidermoid cysts from arachnoid cysts.

Aged↗
PubMed2002

[A case of spermatic granuloma difficult to differentiate from malignant tumor].

A 33-year-old man visited our hospital with complaint of painless left intrascrotal mass. A hard and rough induration in contact with the left testis was palpable. The laboratory data including beta-human churionic gonadotropin, alpha fetoprotein and lactate dehydrogenase were normal. Ultrasound sonography showed a large hypoechoic lesion at the left epididymis. Surgical exploration of this lesion indicated a malignant tumor of the epididymis or spermatic cord, and left high orchiectomy was performed. A milk-white nodule 6 cm in diameter was found in the resected specimen. Pathological diagnosis was spermatic granuloma. Fourteen cases of spermatic granuloma have been reported in the last twenty years in Japan. All of them were relatively small nodules and epididymectomy was performed for most of them. We selected radical orchiectomy because of a large nodule with suspicion of malignant lesion.

Adult↗
PubMed2001

Relation between technetium 99m-methoxyisobutylisonitrile accumulation and multidrug resistance protein in the parathyroid glands.

Technetium 99m ((99m)Tc)-methoxyisobutylisonitrile (MIBI) scintigraphy has been reported to be a useful method for visualizing the parathyroid glands for the diagnosis of hyperparathyroidism. Some drug metabolism transporters, such as p-glycoprotein (P-GP) or multidrug resistance-associated protein (MRP), are believed to be involved with one mechanism of (99m)Tc-MIBI accumulation in the parathyroid glands. We analyzed the expression of P-GP and MRP in 40 parathyroid glands from eight patients with primary hyperparathyroidism and six patients with secondary hyperparathyroidism using an immunohistochemical procedure. These patients underwent (99m)Tc-MIBI scintigraphy and thallium 201 ((201)Tl)/(99m)Tc subtraction scintigraphy preoperatively. We investigated the relation between the scintigraphic images and the expression of P-GP and MRP. The positive findings of (99m)Tc-MIBI accumulation in the hyperfunctioning parathyroids were increased significantly. There was a significant difference between the expression of P-GP and the (99m)Tc-MIBI scintigraphy findings. High expression of P-GP in parathyroid cells resulted in the negative image of (99m)Tc-MIBI, and low or no expression of P-GP made the image positive. There was no significant difference between the expression of MRP and the (99m)Tc-MIBI scintigraphic imaging. The (99m)Tc-MIBI image was also related to the weight of the parathyroid glands but not to the type of the parathyroid cells. Based on these clinical findings, we can hypothesize that P-GP functions as a drug transporter not only for chemotherapeutic agents but also for (99m)Tc-MIBI.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMedDate not supplied

Measuring adsorption of a hydrophobic probe with a surface plasmon resonance sensor to monitor conformational changes in immobilized proteins.

Conformational changes of proteins immobilized on solid matrices were observed by measuring the adsorption of Triton X-100 (TX), a nonionic detergent, as a hydrophobic probe with BIACORE, a biosensor that utilizes the phenomenon of surface plasmon resonance (SPR). Two kinds of proteins, alpha-glucosidase and lysozyme, were covalently attached to dextran matrices on the sensor surface in the flow cell and then exposed to various concentrations of TX solution. We measured SPR signal changes derived from adsorption of TX to the immobilized proteins and calculated the monolayer adsorption capacity using the Brunauer-Emmett-Teller (BET) equation. The results demonstrated that monolayer adsorption capacity is proportional to the amount of immobilized proteins. Further, the unfolding process of immobilized proteins on the sensor surface induced by guanidine hydrochloride was investigated by monitoring SPR signal increases due to the adsorption of TX to the exposed hydrophobic region of the protein. Results strongly suggested that the increase in the SPR signal reflected the formation of the agglutinative unfolded state. We expect our measuring method using the SPR sensor and TX adsorption will be a novel tool to provide conformational information regarding various proteins on solid matrices.

Adsorption↗
PubMedDate not supplied

Prevalence and cognitive performances of clinical dementia rating 0.5 and mild cognitive impairment in Japan. The Tajiri project.

The borderline zone condition between normal aging and dementia is a major issue of concern. Although the term mild cognitive impairment (MCI) is popular, its prevalence and neuropsychological features have not been fully investigated. We investigated the prevalence and neuropsychological features for Clinical Dementia Rating (CDR) 0.5 and MCI. For normal aging, the effects of age and educational level on cognitive performance were examined. We examined 1501 older residents (46.8%) in Tajiri 65 years of age and older. They performed the Cognitive Abilities Screening Instrument (CASI). Depressive scores and subjective memory complaints were also evaluated. There was no age effect but an educational effect on cognitive performance in healthy adults. We found the overall prevalence of CDR 0.5 to be 30.2%, whereas that of MCI was only 4.9%. All CASI domains were deteriorated except for long-term memory and visual construction in the CDR 0.5 participants compared with healthy adults, suggesting that CDR 0.5 is similar to very mild Alzheimer disease. Memory complaints' data suggested that it would be better to exclude memory complaints from the MCI criteria. We considered that the concept of CDR 0.5 would be more applicable to community residents rather than that of the MCI.

Aged↗