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T Yamada

Publications and source records attributed to T Yamada.

At least 91 records · Page 5Linked to original sources
PubMed2003

Evaluation of respiratory status and mandibular movement after total temporomandibular joint replacement in patients with rheumatoid arthritis.

We performed total TMJ replacement to improve respiratory status and correct occlusion in six patients with destruction of the temporomandibular joint (TMJ) caused by rheumatoid arthritis. Morphological changes were evaluated on lateral cephalograms before and after surgery. Respiratory function and mandibular movement were assessed with the use of an apnea-monitor and an LED mandibular tracking device, respectively. After surgery, symptoms such as snoring and daytime sleepiness improved, and solid food could be masticated. Postoperative cephalograms showed that both the posterior airway space and ramal height were significantly improved by surgery. Postoperative records of mandibular movement indicated stability of the occlusion and improvement of mandibular movement, as compared with the preoperative records. Mean oxygen saturation significantly improved 1 month after surgery, whereas apnea and apnea-hypopnea indices did not change significantly.

Aged↗
PubMed2003

Dose-response studies on the induction of liver cytochromes P4501A1 and 1B1 by polycyclic aromatic hydrocarbons in arylhydrocarbon-responsive C57BL/6J mice.

1. To determine the biological effects of 23 polycyclic aromatic hydrocarbons (PAHs) and 3,4,3',4'-tetrachlorobiphenyl, the dose-response studies of the induction of CYP1-dependent xenobiotic oxidation activities by these chemicals in liver microsomes of C57BL/6J mice were studied. 2. In arylhydrocarbon-responsive C57BL/6J mice, the liver microsomal xenobiotic oxidation with substrates of 7-ethoxyresorufin, 7-ethoxycoumarin, (+/-)-benzo[a]pyrene-7,8-diol, dibenzo[a, pyrene-11,12-diol and 2-amino-3,5-dimethylimidazo[4,5-f]quinoline increased by increasing the doses of PAHs to mice, particularly when the PAHs that have been reported to be carcinogenic in experimental animals were used. In arylhydrocarbon receptor-knockout mice, there were no increases in liver microsomal 7-ethoxyresorufin O-deethylation activities nor in liver mRNA levels of CYP1A1, 1A2 and 1B1 by these chemicals. 3. Of the chemicals examined, benzo[k]fluoranthene, benzo[b]fluoranthene, benzo[j]-fluoranthene, 3-methylcholanthrene, dibenz[a,h]anthracene, dibenz[a,c]anthracene and 3,4,3',4'-tetrachlorobiphenyl were potent inducers of the induction of liver microsomal 7-ethoxyresorufin O-deethylation in mice. 4. Other PAHs such as 5-methylchrysene, benzo[a]pyrene, dibenzo[a,l]pyrene, dibenz[a,j]acridine, benzo[a]anthracene and 7,12-dimethylbenz[a]anthracene moderately induced 7-ethoxyresorufin O-deethylation activities in mice. PAHs reported to be weak or less carcinogenic in experimental animals did not induce the xenobiotic oxidation activities of CYP1A1 and 1B1 in the mice. 5. The results suggest that induction of liver microsomal CYP1-dependent xenobiotic oxidation activities is a good tool in determining the potencies of carcinogenic PAHs in arylhydrocarbon-responsive C57BL/6J mice.

Animals↗
PubMed2003

Chromosomal mapping of HSPCB and MYL1 expressed abundantly in the bovine fetus.

Chromosomal mapping of expressed sequence tags for HSPCB and MYL1 expressed abundantly in the bovine fetus was performed by analyzing bovine/murine somatic cell hybrid DNAs with polymerase chain reaction (PCR) using primers specific for those 3'-untranslated regions. HSPCB and MYL1 were assigned to bovine chromosomes 23 and 2, respectively.

Animals↗
PubMed2003

Retinal findings in systemic sclerosis: a comparison with nailfold capillaroscopic patterns.

OBJECTIVE: To determine the prevalence of retinal disease in systemic sclerosis (SSc) and to characterise the findings of retinopathy. Additionally, to analyse the association of retinal disease with other clinical/laboratory findings, particularly the findings of nailfold capillaries in patients with SSc. METHODS: Photographs of the ocular fundi were taken and were evaluated by an ophthalmologist who was unaware of the SSc status of the patients. The nailfold capillaries were analysed with a dermatoscope. Patients were divided into two groups according to the presence (group A) or absence (group B) of retinal disease. RESULTS: Retinal findings of the patients with SSc consisted of hard exudates, vascular tortuosity, microhaemorrhage, and macular degeneration. The prevalence of retinal disease among the patients with SSc was 34% (10/29), compared with 8%(3/38) among the controls (p=0.011). The mean systolic blood pressure and the age of the patients in group A were significantly higher than those in group B. However, there was no significant difference in the nailfold capillary damage between groups A and B. CONCLUSION: Retinal abnormalities are often seen in patients with SSc and they may reflect the vascular changes characteristic of SSc. However, retinal changes may differ in quality from the changes of nailfold capillaries.

Capillaries↗
PubMed2003

Brain lesions in the course of generalised tetanus.

A 47-year-old woman developed left hemiparesis primarily affecting the lower limbs during the course of severe generalised tetanus. MRI on the 82nd hospital day revealed cortical and subcortical lesions predominantly in the right frontal and parietal lobes in addition to marked brain atrophy. Three months later, the enhancing lesions were still present on follow up MRI. We postulate that structures above brainstem may be involved in severe generalised tetanus.

Atrophy↗
PubMed2003

Occipital hypoperfusion in Parkinson's disease without dementia: correlation to impaired cortical visual processing.

OBJECTIVE: The purpose of this study was to analyse changes in regional cerebral blood flow (rCBF) in Parkinson's disease (PD) without dementia. METHODS: Twenty eight non-demented patients with PD and 17 age matched normal subjects underwent single photon emission computed tomography with N-isopropyl-p-[(123)I]iodoamphetamine to measure rCBF. The statistical parametric mapping 96 programme was used for statistical analysis. RESULTS: The PD patients showed significantly reduced rCBF in the bilateral occipital and posterior parietal cortices (p<0.01, corrected for multiple comparison p<0.05), when compared with the control subjects. There was a strong positive correlation between the score of Raven's coloured progressive matrices (RCPM) and the rCBF in the right visual association area (p<0.01, corrected for multiple comparison p<0.05) among the PD patients. CONCLUSIONS: This study showed occipital and posterior parietal hypoperfusion in PD patients without dementia. Furthermore, it was demonstrated that occipital hypoperfusion is likely to underlie impairment of visual cognition according to the RCPM test, which is not related to motor impairment.

Aged↗
PubMed2003

Curvature analysis of the mandibular condyle.

OBJECTIVE: To determine whether curvature analysis on high resolution CT images can be used as a tool for evaluation of mandibular condyle morphology. METHODS: Curvature analysis was performed on reconstructed oblique coronal CT images of 634 normal condyles from 317 patients (144 men and 173 women; age range 4-89 years) with inner or middle ear disease. The condyles were scanned with 1 mm collimation using helical CT. The CT images were analysed manually on a personal computer. RESULTS: The condyle CT images could be categorized into five curvature profile patterns: (1) bi-peak; (2) no peak; (3) tri-peak; (4) bi-peak with an intervening bottom above the base line (bi-peak with a col); and (5) bi-peak with an intervening negative phase. A separate evaluation using computer graphic condyle models indicated that these curvature patterns corresponded to flat (bi-peak), round (no peak), convex (bi-peak with a col), concave (bi-peak with a negative phase) and angled (tri-peak) contours of the condyle's superior surface. The curvature profiles were identical between bilateral condyles in 40% (126/317) of the patients. Gender-related differences in the incidence of the curvature profiles were also found, the bi-peak with a col profile being more frequently observed in women and the bi-peak with a negative phase profile being observed more frequently in men. CONCLUSION: Curvature analysis on CT images depicts condyle morphology effectively and may be an adjunctive tool for condyle morphometry.

Adolescent↗
PubMed2003

Induced sensitization to nickel in guinea pigs immunized with mycobacteria by injection of purified protein derivative with nickel.

Nickel has been reported to be one of the most common causes of allergic contact dermatitis. Despite the fact that nickel is a frequent sensitizer in humans, establishing animal models for nickel allergy has met with considerable difficulties. In clinical cases, allergic contact hypersensitivity to nickel develops much more readily in inflamed skin than normal skin. In this study, we tried to induce nickel sensitization when inflammation has been evoked in guinea pigs immunized with mycobacteria followed by co-administration of a mycobacterial component with nickel. We first examined the delayed-type hypersensitivity (DTH) reaction of mycobacterial components such as the cell wall, cell membrane, 70S ribosomal fraction, cytoplasm, tuberculin purified protein derivative (PPD), RNA and DNA from Mycobacterium bovis BCG in guinea pigs immunized with live M. bovis BCG or heat killed M. tuberculosis. When PPD was used, the hypersensitivity reaction was strongest. Next, we tested whether PPD with nickel could induce nickel sensitivity in guinea pigs immunized with mycobacteria. Strong sensitization to nickel was achieved by injecting PPD with nickel. However, if too large an amount of PPD or nickel salts was used, sensitization to nickel decreased. In this way, sensitization of nickel developed much more easily in guinea pigs immunized with mycobacteria by injection of an appropriate amount of nickel at the inflammation site induced by a suitable amount of PPD.

Animals↗
PubMed2003

The effect of chlorination of estrogenic chemicals on the level of serum vitellogenin of Japanese medaka (Oryzias latipes).

Mature male medaka were continually exposed to four chemicals, p-n-nonylphenol (p-n-NP), nonylphenol (p-NP), bisphenol-A (BPA) and 17beta-estradiol (E2) to evaluate their estrogenic activities in the laboratory. In order to understand the effect of the chlorination that is applied widely in water and wastewater treatment, the above chemicals were chlorinated and then exposed to mature male medaka. Furthermore, in the case of vitellogenin, a is a female specific protein induced by the exposure to test waters containing the above chemicals after 5 weeks, medaka was returned to uncontaminated tap water to determine whether male medaka have a self recovery function from the effect of estrogenic chemicals. Much greater vitellogenin compared to the background levels were induced in the male medaka by separate exposure to 100 microg/L of p-NP, 1,000 microg/L of BPA and 0.05 microg/L of E2. The levels of vitellogenin increased with increasing exposure periods. The relative potencies of these chemicals descended in the order of E2>>p-NP>BPA. Vitellogenin levels inducible by these chemicals were drastically reduced as a result of the chlorination for 24 hours. However, a moderate increase in hepatocyte somatic index (HSI) meant the hepatic fatness was observed as a result of chlorination. It is not clear at this stage whether or not the formation of chlorination byproducts is responsible for this moderate increase in HSI. The vitellogenin concentration of male medaka exposed to chemicals for 5 weeks decreased gradually after return to the uncontaminated water. However, the vitellogenin concentration did not return to the initial normal levels even after 5 weeks. A clear relationship between the serum vitellogenin concentration and the hepatic vitellogenin concentration was also found. Since quantitative analytical procedures for hepatic vitellogenin are easier than those of the serum vitellogenin, measuring the estrogenic effect using the measurement of vitellogenin in liver is recommended.

Animals↗
PubMed2002

Japanese family with parkinsonism, depression, weight loss, and central hypoventilation.

BACKGROUND: The authors describe the clinical and pathologic characteristics of the Fukuoka 1 family, the first Japanese family recognized to have hereditary parkinsonism associated with depression, weight loss, and central alveolar hypoventilation. METHODS: The pedigree contains 14 family members spanning four generations, with five affected individuals. All available medical records were collected for affected members, including autopsy results. RESULTS: The inheritance pattern was autosomal dominant. The average age at onset of symptoms was 41 years. All patients had parkinsonism characterized by rigidity, bradykinesia, and resting and postural tremor. Bradykinesia and depression developed in the proband at age 43 years. He responded to levodopa in the initial stage only. A year later, he had weight loss and central hypoventilation leading to respiratory failure. Symptoms developed in his cousin at age 38 years. The proband's father developed a resting tremor and depression at age 43 years. The tremor was initially responsive to levodopa therapy, but the disease was relentlessly progressive, leading to severe bradykinesia, rigidity, weight loss, and respiratory distress. He died of respiratory failure at age 49 years. Autopsy showed marked neuronal loss and gliosis in the substantia nigra and locus ceruleus. Lewy bodies, neurofibrillary tangles, senile plaques, and other abnormal structures were not seen in the cortical and subcortical regions. CONCLUSIONS: The Fukuoka 1 family shares many clinical and pathologic features with five previously reported kindreds from North America and Europe, suggesting that this syndrome has a worldwide distribution and can occur in different ethnic populations.

Adult↗
PubMed2002

Parainfectious encephalomyeloradiculitis associated with herpes simplex virus 1 DNA in cerebrospinal fluid.

We describe a patient with acute encephalomyeloradiculitis associated with herpes simplex virus 1 (HSV-1) DNA in the cerebrospinal fluid (CSF), and we also review 4 similar cases previously reported from Japan. A 59-year-old man presented with acute encephalitis and urinary retention. Initially, coma and CSF pleocytosis improved with acyclovir treatment, but brain stem encephalitis, transverse myelitis, and lumbosacral polyradiculitis subsequently occurred. These conditions responded to corticosteroid therapy and immunoadsorption plasmapheresis. Polymerase chain reaction detected HSV-1 DNA in the CSF during acute encephalitis but not thereafter. Serial magnetic resonance imaging revealed transient lesions in the thalamus and basal ganglia on both sides of the brain and in the pons, spinal cord, and cauda equina. Acute encephalomyeloradiculitis is a unique neurological syndrome that may be caused by HSV-1 infection of the central nervous system.

Central Nervous System Diseases↗
PubMed2002

Pressure-induced transition from a charge-disproportionated antiferromagnetic state to a charge-uniform ferromagnetic state in Sr(2/3)La(1/3)FeO3.

The perovskite oxide Sr(2/3)La(1/3)FeO3 has been found to switch its electronic ground state drastically at 23 GPa through measurements of 57Fe Mössbauer spectroscopy and powder x-ray diffraction up to 56 GPa. In the low-pressure region a first-order transition from a charge-uniform paramagnetic metallic phase to a charge-disproportionated (3Fe(11/3+)-->2Fe(3+)+Fe5+) antiferromagnetic insulating phase occurs at 207 K at 0.1 MPa and 165 K at 21 GPa, typically. Above 25 GPa, however, a charge-uniform ferromagnetic (and most probably metallic) phase persists below 300 K. This switching occurs at a lattice volume of V(23 GPa)/V(0)(0.1 MPa) = 0.89.

Journal Article↗