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Biomedical subjects

Y Doi

Publications and source records attributed to Y Doi.

At least 19 recordsLinked to original sources
PubMed2006

Decreasing incidence of lacunar vs other types of cerebral infarction in a Japanese population.

BACKGROUND: There is scant information on secular trends in the incidence and survival of ischemic stroke subtypes. METHODS: The authors established three cohorts of Hisayama residents age > or =40 years in 1961 (1,618 subjects), 1974 (2,038 subjects), and 1988 (2,637 subjects). They followed up with each cohort for 12 years, comparing the incidence and survival rate of ischemic stroke subtypes. Morphologic examinations by autopsy or brain imaging was performed on most of the ischemic stroke cases in all cohorts. RESULTS: The age-standardized incidence of lacunar infarction significantly declined by 59% for men and by 28% for women from the first to the second cohort. It continued to decline by 41% for men, but the decline decelerated for women between the second and third cohort. The age-standardized incidence of atherothrombotic infarction tended to decline from the first to the second cohort, whereas it was sustained between the second and third cohort for both sexes. The age-standardized incidence of cardioembolic infarction was unchanged throughout the cohorts. In these cohorts, mean blood pressure levels among hypertensive subjects and the prevalence of current smoker decreased with time, though the prevalence of hypertension remained stable. The 5-year survival rate after lacunar infarction significantly improved among the cohorts, but those of atherothrombotic and cardioembolic infarction did not. CONCLUSIONS: These data suggest that, in the Japanese population, the incidence of lacunar infarction steadily declined for the last 40 years. The improvement of hypertension control and decreasing prevalence of smoking might be responsible for this trend.

Adult↗
PubMed2005

A ninety-day oral toxicity study of a new type of processed gum arabic, from Acacia tree (Acacia senegal) exudates, in F344 rats.

This study was designed to evaluate and characterize any subchronic toxicity of a new type of gum arabic (SUPER GUM [Acacia(sen)SUPER GUM]), a naturally processed polysaccharide exudate from gum acacia trees (Acacia senegal), when administered to both sexes of F344 rats at dietary levels of 0 (control), 1.25%, 2.5%, and 5.0% (10 rats/sex/group). During the study, the treatment had no effects on clinical signs, survival, body weights, and food and water consumption, or on findings of urinalysis, ophthalmology, hematology, or blood biochemistry. Gross pathology and histopathology exhibited no differences of toxicological significance between control and treated rats. Increased relative cecum (filled) weights, evident in both sexes of 5.0% group and females of 1.25% and 2.5% groups, were considered to be a physiological adaptation. Thus, the results indicated the toxic level of SUPER GUM to be more than 5.0%, and the no observed adverse effect level (NOAEL) was concluded to be 5.0% (3,117 mg/kg body weights/day for males, and 3,296 mg/kg body weights/day for males) from the present study.

Administration, Oral↗
PubMed2005

Association between arterial stiffness and platelet activation.

Increased arterial stiffness is strongly associated with atherosclerosis, while platelet activation is an important trigger of thrombotic events in patients with atherosclerosis. However, little is known about the effect of arterial stiffness on platelet activation. We therefore investigated the association between arterial stiffness and platelet activation in 38 normal volunteers (20 men and 18 women) aged 23-77 years (mean = 49 +/- 15 years). Arterial stiffness was assessed by measuring brachial-ankle pulse wave velocity (ba-PWV) and heart-brachial PWV (hb-PWV). Flow cytometric analyses were performed to evaluate platelet activation by measuring surface expression of P-selectin and platelet-neutrophil complexes (PNC) before and after activation by ADP. We also calculated the difference between basal and stimulated states of P-selectin and PNC to assess platelet activation reserve. PWVs were significantly correlated with age and BP (r = 0.60-0.81). For platelet activation and activation reserve, correlations with age were less strong but remained significant (r = 0.36-0.61), with the exception of P-selectin (not significant, NS), and correlations with SBP were similar (r = 0.35-0.53). A significant correlation was found between PWVs and platelet activation (r = 0.43-0.74). Multiple regression analysis demonstrated significant correlations between platelet activation and reserve and PWVs (coefficient = 2.17-6.59), when both age and BP were adjusted for simultaneously. In conclusion, platelet activation was associated with arterial stiffness, suggesting that arterial stiffness may play an important role in thrombotic events.

Adult↗
PubMed2005

Clinical manifestations of chronic inflammatory demyelinating polyneuropathy with anti-cardiolipin antibodies.

OBJECTIVE: Chronic inflammatory demyelinating polyneuropathy (CIDP) is an autoimmune syndrome where certain autoantibodies define clinicopathologic subgroups. In the present study, serum anti-cardiolipin antibodies (aCL) were evaluated. MATERIALS AND METHODS: We investigated aCL in sera from 21 patients diagnosed with CIDP in our hospital between 1991 and 2001. The four CIDP patients with aCL (aCL+) were compared with 17 patients without aCL (aCL-). RESULTS: All aCL+ patients displayed sensory-motor polyneuropathy, with severity and distribution of weakness resembling those in aCL- patients. Anti-nuclear antibody titer of aCL+ patients were significantly higher than those in aCL- patients. None of aCL+ patients presented clinical manifestations of primary anti-phospholipid syndrome (APS), such as thromboses or recurrent abortion. Although the aCL+ patients were older and had more complications and more severe pathologic features than aCL- patients, they responded well to steroid pulse or intravenous immunoglobulin. CONCLUSION: The aCL in CIDP apparently differ from 'autoimmune' aCL in APS, instead being among the autoantibodies pathologically involved in CIDP subgroups.

Adult↗
PubMed2004

Characterization of functional effects of Z-338, a novel gastroprokinetic agent, on the muscarinic M1, M2, and M3 receptors expressed in Xenopus oocytes.

This study characterized the functional effects of a novel gastroprokinetic agent, N-[2-(diisopropylamino)ethyl]-2-[(2-hydroxy-4,5-dimethoxybenzoyl)amino]-1, 3-thiazole-4-carboxyamide monohydrochloride trihydrate (Z338), on the muscarinic M1, M2, and M3 receptors expressed in Xenopus oocytes using the two-electrode voltage clamp method. Z-338 did not produce by itself any currents in oocytes expressing muscarinic M1, M3 receptors or muscarinic M2 receptors/G protein-gated inward rectifying K+ channels (Kir3.1 channels). In oocytes expressing muscarinic M1 receptors, Z-338 inhibited the acetylcholine-induced Ca2+ -activated Cl- current with an IC50 of 1.8 microM. In oocytes expressing muscarinic M2 receptors/Kir3.1 channels, Z-338 inhibited the acetylcholine-induced K+ currents with an IC50 of 10.1 microM, whereas in oocytes expressing muscarinic M3 receptors, Z-338 did not inhibit the acetylcholine-induced Ca2+ -activated Cl- current in a concentration-dependent manner. These results indicate that Z-338 is a potent antagonist not for muscarinic M3 receptor but for both muscarinic M1 and M2 receptors. Thus, Z-338 is a gastrokinetic agent with a unique profile.

Acetylcholine↗
PubMed2004

Development of spontaneous tumours and intestinal lesions in Fhit gene knockout mice.

The fragile histidine triad (FHIT) gene is frequently inactivated in various types of tumours. However, the system-wide pathology caused by FHIT inactivation has not been examined in detail. Here we demonstrate that Fhit gene knockout mice develop tumours in the lymphoid tissue, liver, uterus, testis, forestomach and small intestine, together with structural abnormalities in the small intestinal mucosa. These results suggest that Fhit plays important roles in systemic tumour suppression and in the integrity of mucosal structure of the intestines.

Acid Anhydride Hydrolases↗
PubMed2004

Immunohistochemical demonstration of salmon olfactory glutathione S-transferase class pi (N24) in the olfactory system of lacustrine sockeye salmon during ontogenesis and cell proliferation.

In mammals, glutathione S-transferase (GST) in the olfactory epithelium is involved in assistance of the olfactory reception by the xenobiotic metabolism. We previously reported the protein and gene expressions of salmon olfactory GST class pi (soGST) in the olfactory receptor cells (ORCs) of the salmonid fish. However, the chronological appearances of soGST in ORCs during ontogeny and cell proliferation are still unknown in this species. In this study, we performed immunohistochemistry of soGST using an antibody specific to soGST in the olfactory system (olfactory placode, olfactory pit, olfactory epithelium, olfactory nerve and olfactory bulb) of lacustrine sockeye salmon ( Oncorhynchus nerka) embryos and 5-bromo-2'-deoxyuridine (BrdU) experimental fish. The projection of olfactory nerve bundles from the olfactory pit to the presumptive olfactory bulb was identified at embryonic day 28 after fertilization. The olfactory cilia were first detected on the apical surface of ORCs at day 43. soGST-immunoreactivity was first detected within the olfactory pit cells at day 55. At 58 day, the number of soGST-immunoreactive cells increased markedly in the olfactory epithelia, and soGST-immunoreactive fibers were observed in the olfactory nerves and olfactory bulbs. By in vivo uptake of BrdU in 1-year-old fish, we observed for the first time at day 7 after labeling that the olfactory epithelia showed ORCs in which both soGST-immunoreactivity and BrdU coexisted. These results indicate that soGST is synthesized in the mature ORCs of lacustrine sockeye salmon after cell formation and differentiation.

Animals↗
PubMed2003

Psychosocial impact of the progress of chronic respiratory disease and long-term domiciliary oxygen therapy.

PURPOSE: The psychosocial impact of the progress of chronic respiratory disease and long-term domiciliary oxygen therapy (LTOT) was examined to develop an appropriate intervention strategy for pulmonary rehabilitation programmes. METHODS: Psychosocial factors were investigated using a self-administered questionnaire. A total of 144 patients receiving LTOT were compared with 100 chronic respiratory patients (RES) who were not yet suffering from respiratory failure and therefore not under LTOT, and a control group of 51 healthy subjects (HCS). RESULTS: With the progress of the disease, there was a decrease in daily activities as well as in body mass index. Support of family members and others, life satisfaction, and morale decreased, while the tendency for depression increased significantly. These patterns appeared to begin before initiation of LTOT and worsened in the respiratory failure stage. The negative emotions ranged from 'feeling helpless', 'feeling being a burden and miserable', 'denying LTOT', and 'feeling dependent and anxious'. CONCLUSIONS: For pulmonary rehabilitation programmes, an effective intervention strategy that is suggested from this study should address these psychosocial issues at the initiation of LTOT, and follow through with continuous care throughout life under therapy to counter the development of negative attitudes.

Activities of Daily Living↗
PubMed2003

Chronic active VZV infection manifesting as zoster sine herpete, zoster paresis and myelopathy.

After lumbar-distribution zoster, an HTLV-1-seropositive woman developed chronic radicular sacral-distribution pain (zoster sine herpete), cervical-distribution zoster paresis and thoracic-distribution myelopathy. Detection of anti-varicella zoster virus (VZV) IgM and VZV IgG antibody in cerebrospinal fluid (CSF), with reduced serum/CSF ratios of anti-VZV IgG compared to normal serum/CSF ratios for albumin and total IgG, proved that VZV caused the protracted neurological complications. Diagnosis by antibody testing led to aggressive antiviral treatment and a favorable outcome.

Chronic Disease↗
PubMed2003

Sisters with atypical Fabry's disease with complete atrioventricular block.

A 56 year old woman with severe right heart failure and complete atrioventricular block was referred to hospital for further examination. Symptoms and signs suggestive of Fabry's disease, such as corneal opacities, acroparaesthesias, hypohidrosis, and angiokeratoma, were not noted. Echocardiography showed a diffuse hypertrophic left ventricular wall and paradoxical movement of the interventricular septum. Cardiac catheterisation showed restrictive-type ventricular dysfunction. Left ventricular endomyocardial biopsy showed central vacuolar degeneration of myocytes with inclusion bodies, which had a concentric lamellar configuration under electron microscopy. This finding is specific for Fabry's disease. The patient's elder sister had experienced an almost identical clinical course and histological findings of myocardial cells on necropsy. In conclusion, two sisters were encountered displaying interesting cases of atypical Fabry's disease. Symptoms began with complete atrioventricular block and histological myocardial findings were specific for Fabry's disease.

Biopsy↗
PubMed2002

An immunohistochemical and ultrastructural study of syringocystadenoma papilliferum.

BACKGROUND: Syringocystadenoma papilliferum is a benign hamartomatous tumour of the skin. The histogenesis of this tumour is still controversial. There have been few reports regarding immunohistochemical investigations using only a limited range of antibodies and ultrastructural studies on this rare tumour. OBJECTIVES: To elucidate the immunohistochemical and ultrastructural properties of this tumour. METHODS: We investigated the immunohistological patterns of 12 different anticytokeratin (CK) antibodies and several other markers in five cases of this tumour, comparing them with the patterns in adult sweat glands. One of these cases was also evaluated ultrastructurally. RESULTS: The luminal columnar cells of the tumour were mostly positive for CK7 and more than 70% were positive for CK19. These cells showed the heterogeneous expression of CK1/5/10/14, CK14 and CK5/8. These patterns were also observed in the luminal cells in the secretory or the ductal portion of the adult sweat glands. The basal cuboidal cells of the tumour almost constantly expressed CK1/5/10/14, CK5/8, CK14 and CK7 (except for one case), similar to the patterns of basal cells in the transitional portion and myoepithelial cells in the sweat glands. However, the basal tumour cells expressed CK19 and vimentin heterogeneously, and alpha-smooth muscle actin focally (three cases). Ultrastructurally, the constituent epithelial cells were mainly divided into three types: luminal cells, basal cells and clear cells. The luminal tumour cells bore features of the secretory or ductal luminal cells of sweat glands, although they were somewhat immature in appearance. The basal tumour cells were fundamentally basaloid in nature. The clear cells were undifferentiated or primitive in appearance, suggesting stem or progenitor cell properties. Transitional forms between the clear cells and the other two cell types were also identified. CONCLUSIONS: The tumour epithelium was composed of several cell types demonstrating various developmental stages from the primitive clear cells to the basal cells demonstrating a tendency to differentiate toward basal cells in the apocrine transitional portion or myoepithelial lineage, or luminal cells toward the ductal or secretory epithelium. These results support the classical concept that syringocystadenoma papilliferum is a hamartomatous tumour that arises from pluripotent cells.

Adenoma, Sweat Gland↗
PubMed2002

Protruding atherosclerotic aortic plaques and dyslipidaemia: correlation to subtypes of ischaemic stroke.

AIMS: To evaluate whether thoracic aortic plaques together with dyslipidaemia are related to ischaemic stroke, and if so, to which of the subtypes of stroke. METHODS AND RESULTS: We performed transoesophageal echocardiography in 50 patients with acute ischaemic stroke and in 401 controls. The aorta was divided into two segments: (1) the proximal, proximal to the left subclavian artery, and (2) the distal aorta. Protruding plaques (Intima > or =4 mm in thickness) in the proximal aorta were detected in 14 of the 50 patients (28%) with stroke, and in 53 of the 401 controls (13%) (P<0.01). Plaque score in the proximal aorta (2.1 +/- 1.8 vs 0.9 +/- 0.7; P<0.05), low-density lipoprotein cholesterol level (3.60 +/- 0.85 vs 2.87 +/- 0.72 mmol/l; P<0.05), and apolipoprotein B/A-I ratio (0.98 +/-0.17 vs 0.73 +/- 0.16; P<0.005) were higher in patients with athero-thrombotic than in cardioembolic stroke. The score in the proximal aorta correlated with low-density lipoprotein cholesterol level (r=0.44, P<0.005) and apolipoprotein B/A-I ratio (r=0.40, P<0.01). CONCLUSION: Severe plaques in the proximal aorta together with dyslipidaemia are seen more frequently in patients with atherothrombotic stroke. Lipid analysis may contribute to the prediction and the treatment of the patients who are at high risk for atherothrombotic stroke.

Acute Disease↗
PubMed2002

Left ventricular diastolic function assessed using Doppler tissue imaging in patients with hypertrophic cardiomyopathy: relation to symptoms and exercise capacity.

BACKGROUND: Conventional Doppler indices of left ventricular diastolic function do not correlate with symptoms or exercise capacity in patients with hypertrophic cardiomyopathy, because of their dependence on loading conditions. Diastolic mitral annular velocity measured using Doppler tissue imaging has been reported to be a preload independent index of left ventricular diastolic function. OBJECTIVE: To determine the relation between diastolic annular velocities combined with conventional Doppler indices and symptoms or exercise capacity in hypertrophic cardiomyopathy. METHODS: 85 patients with hypertrophic cardiomyopathy and 60 normal controls were studied. Diastolic mitral annular velocities, transmitral left ventricular filling, and pulmonary venous velocities were measured. RESULTS: Early diastolic velocities at lateral and septal annulus were lower in patients with hypertrophic cardiomyopathy than in controls (lateral Ea: 10 (3) v 18 (4) cm/s, p < 0.0001; septal Ea: 7 (2) v 12 (3) cm/s, p < 0.0001). Unlike conventional Doppler indices alone, transmitral early left ventricular filling velocity (E) to lateral Ea ratio correlated inversely with peak oxygen consumption (r = -0.42, p < 0.0001). Patients in New York Heart Association (NYHA) class III had a higher transmitral E to lateral Ea ratio (12.0 (4.6)) than those in NYHA class II (7.6 (3.1), p < 0.005) or class I (6.6 (2.6), p < 0.0001). CONCLUSIONS: Early diastolic mitral annular velocities are reduced in patients with hypertrophic cardiomyopathy. Unlike conventional Doppler indices alone, the transmitral E to lateral Ea ratio correlates with NYHA functional class and exercise capacity.

Adolescent↗
PubMed2002

Disorganization of honey-comb immunoreactive pattern of desmin and plectin in rat atrophic soleus muscle fiber induced by hindlimb suspension.

Immunoreactivity for desmin, plectin and alpha-actinin was investigated in rat atrophic soleus muscle fibers induced by hindlimb suspension between 1 and 4 weeks (hindlimb suspension group, HSG), and compared with that of the control group (CG). Some of the HSG for 4 weeks were allowed unrestricted cage activity for 2 weeks as the recovery group (RG). In the cross-sectioned muscle fibers of the CG, desmin and plectin showed honey-comb immunoreactive patterns extending throughout the sarcoplasm. Superimposed images by double immunofluorescence labeling showed overlapping of both immunoreactivities. In the longitudinally sectioned profiles, superimposed images of alpha-actinin and desmin were overlapped at the level of Z-discs. The focal disorganization of the above honeycomb immunoreactive patterns, followed by the reduction of the cross-sectional area (CSA) of atrophic soleus muscle fibers and the appearance of Z-streaming, uniquely arose in the HSG from the first week and extended throughout the sarcoplasm in proportion to the suspension period. Such honey-comb patterns of both desmin and plectin were already restored in the RG at 2 weeks, followed by the disappearance of Z-streaming, prior to the recovery of the CSA. These findings indicate that the disorganization of topological and structural relationships of desmin and plectin with Z-discs surrounding individual myofibrils is primarily evoked, which leads to Z-streaming of atrophic soleus muscle fibers, and that the restoration of the muscle activity results in an early arrangement recovery of desmin and plectin around myofibrils.

Animals↗
PubMed2002

Enhanced expression of endothelin-1 and endothelin-converting enzyme-1 in acute hypoxic rat aorta.

Deeply anesthetized male Wistar rats were perfused by Hanks' balanced salt solution bubbled with either 95%air and 5%CO2 (normoxic group) or 95%N2 and 5%CO2 (hypoxic group) from the thoracic aorta for 30 min, and the isolated abdominal aortae from both groups were used for electron microscopy, immunocytochemistry of endothelin (ET)-1 and ET-converting enzyme (ECE)-1, and in situ hybridization of preproET-1 mRNA. A remarkable increase in the number of Weibel-Palade (WP) bodies, storage sites of ET-1 and ECE-1, occurred in the hypoxic group when compared to the normoxic group. Immunoreactivities for ET-1 and ECE-1, and signals for preproET-1 mRNA were seen along the endothelia of both groups, but the intensities were significantly elevated in the hypoxic group. The increase in the number of ECE-1 immunoreactive gold particles was noticed especially in WP bodies in the hypoxic group. These findings indicate the enhancement of preproET-1 synthesis in the aortic endothelial cells as well as the acceleration of ET-1 processing in increased WP bodies in such cells in an experimentally hypoxic condition of the rat aortae.

Acute Disease↗
PubMed2002

Status of NAT screening for HCV, HIV and HBV: experience in Japan.

The first nationwide nucleic acid amplification testing (NAT) for hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus type 1 (HIV-1) of voluntarily donated blood after serological pre-screening and before release of cellular components and plasma for fractionation was implemented by the Japanese Red Cross Blood Transfusion Services. The NAT screening assay using multiplex reagent is time-saving, cost effective, and labour-saving procedure for all blood and blood products including short-shelf life platelets. During the 50-mini-pool NAT screening of serologically negative donations (February 1, 2001-April 30, 2001), we were able to screen out 112 HBV-positive, 25 HCV-positive, and 4 HIV-1 positive units from blood and blood components.

Blood↗
PubMed2001

Roles of long chain fatty acids and carnitine in mitochondrial membrane permeability transition.

Palmitoyl-CoA (Pal-CoA) lowered the respiratory control ratio (RCR), and induced mitochondrial membrane permeability transition (MPT) and cytochrome c (Cyt. c) release from isolated rat liver mitochondria. L-Carnitine suppressed the Pal-CoA-induced dysfunction, MPT, and Cyt. c release of isolated mitochondria. This suppression was inhibited by cephaloridine, an inhibitor of carnitine uptake into mitochondria. Cyclosporin A (CsA), an inhibitor of MPT, and BSA also suppressed the Pal-CoA-induced MPT. In the presence of inorganic phosphate (P(i)), Ca2+-induced MPT was suppressed by BSA, L-carnitine, and chlorpromazine, an inhibitor of phospholipase A2. In the presence of a low concentration of Ca2+, 3,3',5-triiodothyronine, long chain fatty acids, salicylic acid, and diclofenac induced MPT by a mechanism that was suppressed by BSA, L-carnitine, or chlorpromazine. During the incubation of mitochondria on ice, their respiratory competence decreased; L-carnitine and BSA also prevented this decrease. Mitochondrial depolarization in pheochromocytoma PC12 cells was induced by either serum deprivation or arachidonic acid by a mechanism that was suppressed by acetyl-L-carnitine. These results indicate that some MPTs may be regulated by fatty acid metabolism and that the Pal-CoA-induced MPT plays an important role in the induction of apoptosis.

Animals↗