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Y Kokubo

Publications and source records attributed to Y Kokubo.

At least 19 recordsLinked to original sources
PubMed2007

Effect of implant support on distal extension removable partial dentures: in vitro assessment.

The implants in implant-supported removable partial dentures (RPDs) are placed in the edentulous ridge to stabilize the RPD and minimize the resultant rotational movement. This study investigated the effect of implant placement on RPD stability. A model simulating a mandibular bilateral distal extension missing was fabricated using epoxy resin and silicone impression material as thin (1 mm) and thick (2 mm) soft tissues. Five pressure sensors (PS-10K, Kyowa, Tokyo, Japan) were attached near the left and right first molars (#36 and #46), first premolars (#34 and #44) and medio-lingual alveolar crest. Five bilateral distal extension RPDs with Co-Cr frameworks were conventionally fabricated. After the implants were placed at the bilateral second molar areas, healing caps (4.5 mm high) were connected to the denture base with autopolymerized resin to support the RPD. As in a conventional RPD, sealing screws were placed without connecting them. Loads up to 5 kg were applied, and the pressure and displacement of the RPDs (n = 5) were simultaneously measured and analysed using the Wilcoxen test (alpha = 0.05). There was less pressure on both thin and thick soft tissues, the #36, #46 and the medio-lingual alveolar crest from the implant-supported RPD than from the conventional RPD (P < 0.05). There were no significant differences in pressure on #34 and #44 between the two RPDs (P > 0.05). There was significantly less denture displacement of the implant-supported RPD than of the conventional denture (P < 0.05). Implant support helped prevent the displacement of distal extension RPDs and decreased the pressure on soft tissues.

Denture Bases↗
PubMed2006

Surgical resection of tumors located in subcortex of language area.

OBJECT: Although functional mapping facilitates the planning of surgery in and around eloquent areas, the resection of tumors adjacent to language areas remains challenging. In this report, we took notice that the language areas (Broca's and Wernicke's) present at the perisylvian fissure. We posit that if there is non-essential language area on the inner surface of the Sylvian fissure, safe tumor resection may be possible even if the tumor is located under the language cortex. METHODS: The study population consisted of 5 patients with intrinsic brain tumors (frontal glioma, n = 3; temporal cavernous angioma, n = 1; primary malignant central nervous system lymphoma, n = 1) located in the perisylvian subcortex, in the language-dominant hemisphere. All patients underwent awake surgery and we performed intra-operative bipolar cortical functional language mapping. When the tumor was located under the language area, the Sylvian fissure was opened and the inner surface of the opercular cortex was exposed with the patient asleep, and additional functional mapping of that cortex was performed. This enabled us to remove the tumor from the non-functioning cortex. In our series, 4 of 5 patients had not language function on the inner surface of the operculum. Only one patient, a 52-year-old man with frontal glioblastoma (Case 3) had language function on the inner surface of the frontal operculum. CONCLUSION: We suggest that even perisylvian tumors located in the subcortex of the language area may be resectable via the nonfunctioning intrasylvian cortex by a transopercular approach without resultant language dysfunction.

Adult↗
PubMed2006

Plasma protein S activity correlates with protein S genotype but is not sensitive to identify K196E mutant carriers.

BACKGROUND: Protein S (PS) is an anticoagulant protein that functions as a cofactor for activated protein C (APC), and congenital PS deficiency is a well-known risk factor for the development of deep vein thrombosis (DVT). Recently, we and others identified the K196E missense mutation in the second epidermal growth factor-like domain of PS as a genetic risk factor for DVT in the Japanese population. The incidence of this mutation is high in the Japanese population. OBJECTIVES: In the present study, we investigated the relationship between plasma PS activity and the presence of the K196E mutation. PATIENTS AND METHODS: We measured PS activity as a cofactor activity for APC in 1,862 Japanese individuals and determined the PS K196E genotype in this population. RESULTS: Individuals heterozygous for the mutant E-allele had lower plasma PS activity than wildtype subjects (mean +/- SD, 71.9 +/- 17.6%, n = 34 vs. 87.9 +/- 19.8%, n = 1,828, P < 0.0001). However, the PS activity of several heterozygous individuals (n = 8) was greater than the population average. In contrast, multiple wildtype subjects (n = 26) had PS activity less than 2 SD below the population mean, indicating that other genetic or environmental factors affect PS activity. CONCLUSIONS: Plasma PS activity itself is not suitable for identifying PS 196E carriers and other methods are required for carrier detection.

Adult↗
PubMed2005

Cervical angina: a seemingly still neglected symptom of cervical spine disorder?

STUDY DESIGN: Retrospective, case series. DESIGN: A review of 10 surgical cases with symptoms of cervical angina. OBJECTIVE: To stress the importance of symptoms of cervical angina in patients with cervical spine disorders. SETTING: Fukui University Hospital, Japan. RESULTS: A total of 10 patients complaining of symptoms of cervical angina were admitted with a tentative diagnosis of coronary artery disease. Pain relief was achieved by anterior surgical decompression in all patients. CONCLUSION: We stress that physicians should be aware of the symptoms of cervical angina and that surgical intervention often leads to complete relief of symptoms.

Adult↗
PubMed2005

Reduction of PTEN protein and loss of epidermal growth factor receptor gene mutation in lung cancer with natural resistance to gefitinib (IRESSA).

Gefitinib (IRESSA), an epidermal growth factor receptor (EGFR) tyrosine kinase (TK) inhibitor, has antitumour activity in the advanced non-small-cell lung cancer (NSCLC) setting. However, in chemotherapy-naïve patients with advanced NSCLC, the addition of gefitinib to standard chemotherapy regimens failed to increase survival. These results suggest the need for improved patient selection and combination rationales for targeted therapies. We have identified subpopulations of an adenocarcinoma cell line that are naturally resistant to gefitinib, and have analysed the cDNA expression profiles, genomic status of EGFR gene and the effect of gefitinib on signalling pathways in these cell lines in order to identify key mechanisms for naturally acquired resistance to gefitinib. Gefitinib-resistant subpopulations demonstrated increased Akt phosphorylation (not inhibited by gefitinib), reduced PTEN protein expression and loss of the EGFR gene mutation when compared with parental cell lines. These differences in Akt and PTEN protein expression were not evident from the cDNA array profiles. These data suggests that (1) the EGFR gene mutation may be possibly lost in some cancer cells with other additional mechanisms for activating Akt, (2) reintroduction of PTEN or pharmacological downregulation of the constitutive PI3K-Akt-pathway activity may be an attractive therapeutic strategy in cancers with gefitinib resistance.

Adenocarcinoma↗
PubMed2005

Primary osteosarcoma of the thoracic spine: report of an unusual elderly patient with autopsy findings.

STUDY DESIGN: A case report of primary osteosarcoma of the spine in an elderly patient. OBJECTIVE: The histopathological features of osteosarcoma vary widely, often leading to diagnostic difficulties particularly when there is little evidence of osteoid formation. The report describes the difficulty in the diagnosis of osteosarcoma of the thoracic vertebra. SETTING: Department of Orthopaedics and Rehabilitation Medicine, Fukui University Faculty of Medicine, Fukui, Japan. METHOD: A 78-year-old man presented with paraparesis and underwent urgent anterior excision of a primary spinal tumor emanating from the T10 vertebra followed by artificial vertebral replacement. The patient eventually died of disseminated disease of vertebral osteosarcoma. RESULTS: Samples from the T10 vertebral tumor showed neoplastic growth of atypical spindle-shaped cells, with foci of storiform-like proliferation. The tissue also demonstrated positive immunohistochemical staining for vimentin and alpha-smooth muscle actin and a tentative diagnosis of leiomyosarcoma was made. However, a metastatic nodule of the chest wall at autopsy showed focal osteoid formation, a finding not seen in the primary tumor. CONCLUSION: Early detection and accurate diagnosis is important for improving not only patient prognosis but also the quality of life. We should always consider this rare entity, particularly in elderly patients who present with back pain and vertebral collapse.

Actins↗
PubMed2005

Clinical marginal and internal gaps of Procera AllCeram crowns.

This study evaluated the marginal and internal gaps of Procera AllCeram crowns in vivo using silicone materials. Ninety Procera AllCeram crowns were evaluated before final cementation. White and black silicone materials were used to record the marginal and internal fit; then the crowns were sectioned bucco-lingually and mesio-distally to measure the thickness of the silicone layer using a microscope. Sixteen reference points were measured on each specimen. Mean marginal gaps among anterior, premolar and molar teeth, and mean gaps at the reference points within the groups were compared by analysis of variance and Dunnett T3 test. The mean values at the margins were the smallest in all tooth groups, whereas those at the rounded slope of the chamfer were the largest. There were significant differences (P < 0.001) in the mean gaps at the four reference points (margin, rounded slope of the chamfer, axial wall and occlusal surface) in each group, except for the molar teeth. The mean marginal gaps of the Procera AllCeram crowns were within the range of clinical acceptance.

Aluminum Oxide↗
PubMed2005

Clinical marginal and internal gaps of In-Ceram crowns fabricated using the GN-I system.

The marginal and internal gaps of ceramic crowns with alumina copings fabricated using a computer-aided design, computer-aided manufacturing system, were evaluated in vivo using silicone materials. Black and white silicone materials were used to record the marginal and internal gaps of 82 In-Ceram crowns before final cementation. The silicone materials were sectioned bucco-lingually and mesio-distally and viewed under a microscope to measure the thickness of the white silicone layer. Sixteen reference points were measured on each specimen. The mean marginal gaps were compared among the anterior, premolar and molar teeth, and the mean gaps at the reference points within the groups were compared by analysis of variance and the Dunnett T3 test. The mean marginal gap was 66.8 mum. There were no differences in marginal gaps among the three groups. In all the groups, the marginal gaps were the smallest, whereas the occlusal gaps were the largest. The mean marginal gaps of the In-Ceram crowns with the alumina copings fabricated using the GN-I system were within the range of clinically acceptable values.

Aluminum Oxide↗
PubMed2001

Role of the liver in regulating numbers of circulating neutrophils.

Neutrophils (polymorphonuclear leukocytes [PMNs]) carry potent destructive enzymes that can destroy invasive bacteria or damage normal tissue. PMNs have a half-life of only 6 hours in the blood, but the details of this homeostasis are unknown. In a rat model of endotoxemia, P-selectin was selectively up-regulated in hepatic sinusoids and veins where it was necessary for phagocytosis of PMNs by Kupffer cells in the liver, as opposed to the spleen or the lungs. Apoptotic PMNs appeared in the lungs and spleen only after inactivation of Kupffer cells by gadolinium chloride (GdCl(3)). Blocking of Fas protein reduced the number of apoptotic cells in the liver; binding of annexin V to phosphatidylserine (PS) reduced the number of PMNs phagocytosed by Kupffer cells. The results support a clearance pathway in which apoptosis and phagocytosis are effected by Kupffer cells after P-selectin-mediated sequestration. (Blood. 2001;98:1226-1230)

Animals↗
PubMed2001

Herniation of cervical intervertebral disc: immunohistochemical examination and measurement of nitric oxide production.

STUDY DESIGN: Surgically obtained cervical herniated intervertebral discs were examined histologically and immunohistochemically. The production of nitric oxide (NO) in the local tissue was examined using the electron spin resonance (ESR) method. OBJECTIVES: To investigate the local histologic and immunohistochemical changes in cervical disc herniation, including NO production, and to compare such changes with those in autopsy cases. SUMMARY OF BACKGROUND DATA: Very little is known about the histopathologic processes of cervical disc herniation. In addition, no information is available on the level of in vivo NO production in cervical disc herniation. METHODS: Thirty-six herniated cervical discs obtained from 31 patients were immunohistochemically examined for localization of blood vessels, matrix metalloproteinase (MMP)-3, and inducible NO synthetase (iNOS). We also compared the production of NO, measured by the ESR method, in eight specimens with that of five control discs obtained from fresh cadavers. RESULTS: The presence of herniated discs correlated with the degeneration of cartilaginous endplate and torn anulus fibrosus. Formation of new blood vessels around the herniated discs was detected, using von Willebrand factor antibody, in seven uncontained hernias and 20 contained hernias. Immunohistochemical studies showed the presence of cells positive for MMP-3 (chondrocytes), iNOS (chondrocytes and granulation tissue) in cervical disc hernias. ESR analysis showed a significantly higher NO production in herniated cervical discs than in disc samples of fresh cadavers. CONCLUSIONS: Herniated cervical intervertebral disc is characterized by the presence of an inflammatory process associated with neovascularization and increased expression of MMP-3. Production of NO was markedly high in both contained- and uncontained-type hernias.

Adult↗
PubMed2001

Dehydroepiandrosterone sulphate is increased and dehydroepiandrosterone-response to corticotrophin-releasing hormone is decreased in the hyperthyroid state compared with the euthyroid state.

OBJECTIVE: Dehydroepiandrosterone (DHEA) and DHEA-sulphate (S) have been suggested to play protective roles in many pathological states, some of which are observed in hyperthyroidism. If DHEA and DHEA-S levels change in hyperthyroidism, they might participate as a possible causative link with such pathophysiological changes in hyperthyroidism. However, the CRH-ACTH-DHEA system in hyperthyroidism has not been clearly defined. We examined plasma levels of DHEA and DHEA-S together with ACTH and cortisol in both hyperthyroid (Hyper) and euthyroid states (Eu). METHODS: Eighteen patients (5 men and 13 women, aged 46.9 +/- 2.8 years) with Graves' disease were studied before treatment and again in the euthyroid state following treatment with methimazole. A 100 microg hCRH stimulation test and a low-dose (0.5 microg) 1-24 ACTH stimulation test were performed on separate days. Basal levels and A area under the response curve (AUC) were compared between Hyper and Eu. RESULTS: DHEA-S was higher in Hyper than in Eu. However, basal DHEA did not differ between Hyper and Eu. The ratio of DHEA to DHEA-S was lower in Hyper than in Eu. AAUC of DHEA during a CRH test was lower in Hyper than in Eu. However, AAUC of DHEA during an ACTH test was similar in both Hyper and Eu. Basal ACTH was higher in Hyper than in Eu. In both CRH and ACTH tests, AAUC of cortisol response was lower in Hyper than in Eu, although the basal cortisol level was not different. CONCLUSION: The balance of the conversion between DHEA-S and DHEA in the hyperthyroid state favoured DHEA-S. Similar to cortisol, the DHEA response in the CRH test in hyperthyroidism seemed to be insufficiently compensated for by increased ACTH, although the DHEA response to low-dose ACTH was similar in the hyperthyroid and euthyroid states. Increased DHEA-S might play some role in the pathological states in many organs in hyperthyroidism.

Adrenocorticotropic Hormone↗
PubMed2001

Apolipoprotein E genetic polymorphism and stroke subtypes in a Bangladeshi hospital-based study.

The association between apolipoprotein E (apoE) genetic polymorphism and stroke has not been concordant in different racial populations. We investigated the association between apoE genotypes and stroke subtypes by a case-control study in Bangladesh for the first time among south Asian countries. First-ever-stroke patients (n=227; cerebral infarction, n=147, cerebral hemorrhage, n=80) and 190 controls were recruited from a hospital in Dhaka, Bangladesh. The diagnosis of stroke was based on CT and clinical findings. Cerebral infarction was classified anatomically into cortical and penetrating region. Infarction in the cortical region was further categorized etiologically into thrombosis and embolism. Cerebral hemorrhage was considered as a whole in all analyses. ApoE genotypes were determined by restriction fragment length polymorphism. In the multivariate conditional logistic regression analysis adjusted for potential confounders both the epsilon3/epsilon4 genotype and epsilon4 carrier conferred an approximately 3-fold increased risk for cerebral thrombosis in the cortical artery region (OR 3.5, 95% CI 1.2 to 10.4 and OR 3.1, 95% Cl 1.1 to 9.0, respectively) compared with epsilon3/epsilon3 genotype. However, when the analysis was restricted to the elderly (>60 years), epsilon 2 carrier was associated with a risk of hemorrhagic stroke (OR 19.2, 95% CI 1.3 to 295.2). Our study suggested that both apoE epsilon3/epsilon4 genotype and epsilon4 carriers were risk factors for cerebral thrombosis in cortical artery region, whereas epsilon 2 carrier was a risk factor for hemorrhagic stroke in the elderly.

Aged↗
PubMed2001

Practical application of predictive microbiology software programs to HACCP plans.

We studied how predictive microbiology models could practically be applied to HACCP plans with two predictive software programs that are currently available. The software programs were the Food Micromodel elaborated by the Ministry of Agriculture, Fisheries, and Food, U.K. and the Pathogen Modeling Program of Eastern Regional Research Center, U.S. Department of Agriculture. They successfully provided useful information on (i) the determination of Critical Control Points (CCPs), (ii) the estimation of critical limits at CCPs, (iii) the decision of abused products, (iv) the assessment of equivalence of HACCP plans, and further (v) the development of new products. With the information simulated by the software programs, HACCP teams could make scientific and objective decisions for developing their individual plans. It was also confirmed that microbiological process standards for food processing are indispensable for the application of the predictive programs to HACCP plans.

Food Microbiology↗
PubMed2001

Familial amyotrophic lateral sclerosis and parkinsonism-dementia complex of the Kii Peninsula of Japan: clinical and neuropathological study and tau analysis.

We report the first case of neuropathologically verified parkinsonism-dementia complex of the Kii peninsula, together with the patient's brother, who had amyotrophic lateral sclerosis. The propositus woman developed parkinsonism and dementia at 63 years of age and died at 70 without displaying clinical features of amyotrophic lateral sclerosis. The brain exhibited marked atrophy of the frontal and temporal lobes. Microscopically, there were many neurofibrillary tangles in the central nervous system, most markedly in the mesial temporal lobe and deep nuclei, as well as changes of amyotrophic lateral sclerosis but no senile plaques or Lewy bodies. Neurofibrillary tangles exhibited twisted tubule structures on electon microscopic examination, and an analysis of insoluble tau protein extracted from the fresh brain revealed a 60-, 64-, 68-kD triplet. The tau gene exhibited no mutations. Her brother developed progressive bulbar palsy-type amyotrophic lateral sclerosis at 45 years of age and died at 49 without presenting with dementia or parkinsonism. Neuropathological examination revealed not only pathologic features of amyotrophic lateral sclerosis but also a moderate number of neurofibrillary tangles in the temporal cortex and deep nuclei. The siblings were neuropathologically similar despite their different clinical manifestations. These findings suggest that amyotrophic lateral sclerosis and parkinsonism-dementia complex of this family may be phenotypic variants of a tauopathy caused by genetic abnormalities.

Aged↗
PubMed2001

[Apolipoprotein E].

Explore the source record for details and available documents.

Apolipoproteins E↗
PubMed2001

[Neurological and neuropathological studies of amyotrophic lateral sclerosis/parkinsonism-dementia complex in the Kii Peninsula of Japan].

Hohara and Kozagawa in the Kii peninsula of Japan are reported to be high-incidence foci of amyotrophic lateral sclerosis (Kii ALS) and parkinsonism-dementia complex (Kii PDC). During the period between 1996 and 1999, three Kii ALS patients and 19 Kii PDC patients were confirmed neurologically in Hohara among which, one Kii ALS patient and two Kii PDC patients were examined neuropathologically. The ratio of positive family history where ALS or PDC occurred within the fourth degree of the relatives was 33.3% in the patients with Kii ALS, 78.9% in those with Kii PDC, and 72.7% in total. The ages of onset were between 57 years and 63 years (mean age: 60.0 years) in the patients with Kii ALS and between 53 years and 74 years (mean age: 66.5 years) in those with Kii PDC. All of the Kii ALS patients were female, and the male to female ratio of the Kii PDC patients was 1:1.7. The clinical features of Kii ALS were basically similar to those of classical ALS. The core clinical features of Kii PDC consisted of dementia and parkinsonism, frequently accompanied by motor neuron symptoms. The cardinal neuropathological features of Kii ALS/PDC included many neurofibrillary tangles (NFTs) associated with loss of nerve cells in the cerebral cortex and the brain stem, as well as morphological alterations diagnostic of ALS. Ultrastructurally, NFTs consisted of paired helical filaments. When we compared the clinical features of these Kii ALS patients with those that had been surveyed in 1969, the male to female ratio changed from male dominance to female dominance and the mean age of the onset of the disease was delayed by approximately 10 years. The most frequent initial symptom had been weakness of the lower limbs in the survey in 1969 and was bulbar palsy in this study. As to Kii PDC, this is the first report of the clinical features of many cases.

Aged↗