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Biomedical subjects

H Hoshi

Publications and source records attributed to H Hoshi.

At least 163 records · Page 9Linked to original sources
PubMed1995

Graves ophthalmopathy: MR evaluation of 10-Gy versus 24-Gy irradiation combined with systemic corticosteroids.

PURPOSE: To establish the most effective radiation dose for treatment of Graves ophthalmopathy (GO). MATERIALS AND METHODS: A combination of 10 Gy (n = 15) or 24 Gy (n = 16) of radiation and corticosteroids was used to treat 31 patients with GO. Magnetic resonance (MR) images obtained before treatment showed swollen extraocular muscles with prolonged T2 relaxation times in all patients. RESULTS: Before therapy, T2 relaxation time of extraocular muscle was 79.6 msec (95% confidence interval, 76.3, 82.9) in the 24-Gy group and 77.4 msec (95% confidence interval, 74.6, 80.1) in the 10-Gy group (P = .32). After therapy, T2 relaxation time was 62.8 msec (95% confidence interval, 61.2, 64.4) in the 24-Gy group and 68.9 msec (95% confidence interval, 66.8, 71.1) in the 10-Gy group. In the 24-Gy group, there was a significant decrease in T2 relaxation times (P = .001) and clinical response to initial treatment was better. At 1- and 3-month follow-up, the resistance rate was lower in the 24-Gy group. CONCLUSION: In treatment of GO, 24 Gy of radiation is a more effective dose than 10 Gy when combined with systemic corticosteroids.

Conjunctival Diseases↗
PubMed1995

Epithelial modulation of leukotriene-C4-induced human tracheal smooth muscle contraction.

We investigated the role of epithelium in smooth muscle contraction induced by leukotriene C4 (LTC4) in isolated human trachea. The contractile response to LTC4 was potentiated by a gamma-glutamyl transpeptidase (gamma-GTP) inhibitor L-serine borate and by removal of the epithelium. Both L-serine borate (4.5 x 10(-2) M) and removal of the epithelium shifted the concentration-response curves to LTC4 to lower concentrations by 1.2 and 1.0 log units, respectively. Incubation of cultured human tracheal epithelial cells with either LTC4 or LTD4 resulted in the formation of LTD4 or LTE4. The isolated epithelial cells and cultured epithelial cells contained gamma-GTP activity. Histochemical study indicated that gamma-GTP-like activity was present in the epithelial, submucosal, and smooth muscle layers. These findings suggest that the epithelium modulates the contractile response to LTC4 in human trachea by LT-degrading enzymes.

Aged↗
PubMed1995

In situ expression of the cell adhesion molecules in bronchial tissues from asthmatics with air flow limitation: in vivo evidence of VCAM-1/VLA-4 interaction in selective eosinophil infiltration.

Eosinophils play a critical role in the pathogenesis of bronchial asthma by releasing various mediators. To understand the mechanisms of eosinophil migration to the site of inflammation, we examined the expression of adhesion molecules in the bronchial tissues of asthmatic subjects with air flow limitation. By immunohistochemical analysis, Mac-1, LFA-1, and VLA-4 were strongly positive in eosinophils and mononuclear cells infiltrated in the bronchial mucosa and submucosa. Their number was significantly increased compared with those in control tissue. Immunolocalization for ICAM-1, the ligand of Mac-1 and LFA-1, was detected in the endothelial cells of capillaries and venules, in the mononuclear cells in submucosa, and in the basal layer of the epithelium. Endothelial cells in capillaries and venules were also strongly positive for VCAM-1, the ligand of VLA-4. Immunolocalization for E-selectin was detected in some endothelial cells in capillaries and venules in bronchial submucosa, whereas there were very few positive cells in the bronchial tissues from control subjects. In situ hybridization demonstrated ICAM-1 mRNA expression in the endothelial cells and mononuclear cells in bronchial submucosa. Immunoelectron microscopy for ICAM-1, VCAM-1, and E-selectin demonstrated de novo synthesis of these molecules and their expression along the luminal cell membrane of endothelial cells. These results suggested that ICAM-1, VCAM-1, and E-selectin were newly synthesized prior to spontaneous asthma attacks, and that their expression, particularly that of VCAM-1, may play a key role in eosinophil infiltration into the airway.

Adult↗
PubMed1995

Eosinophil penetration through cultured human airway epithelial cell layer.

We investigated the mechanisms of eosinophil penetration and mannitol permeability through a multilayer of cultured human tracheal epithelial cells. Wells of tissue culture plates were separated into the upper and the lower chambers by the cultured epithelial cell layer. 51Cr-labeled eosinophils or 3H-mannitol were put into the lower chamber. To stimulate the epithelial cells, platelet-activating factor (PAF) and/or phorbol myristate acetate (PMA) were added to the upper chamber. After 4 h of incubation, the eosinophil penetration rate was determined as a percentage of the total count added to the lower chamber. PMA significantly increased the eosinophil penetration rate in a dose-dependent manner (4.0% at 10(-5) M), compared with control (0.67%), whereas PAF itself did not. Activation of eosinophils by the addition of PAF to the lower chamber produced a significant increase in the eosinophil penetration (6.5% at 10(-6) M), which was inhibited by staurosporine. For determining the mannitol permeability, PMA, PAF, and/or supernatant from eosinophils were added to both upper and lower chambers and incubated for 30 min. PMA induced a significant increase in the mannitol permeability (175% of controls at 10(-5) M), whereas PAF itself did not alter it. Supernatant from eosinophils activated by PAF (10(-6) M) significantly increased the permeability (451% of controls), which was blocked by staurosporine. Supernatants from AA861 (a 5-lipoxygenase inhibitor)-treated or phenidon (a phospholipase A2 inhibitor)-treated eosinophils activated by PAF failed to alter the supernatant-induced increases in mannitol permeability.(ABSTRACT TRUNCATED AT 250 WORDS)

Alkaloids↗
PubMed1995

Eosinophils as a potential source of platelet-derived growth factor B-chain (PDGF-B) in nasal polyposis and bronchial asthma.

Tissue remodeling in bronchial tissues from asthmatics as well as in nasal polyp (NP) tissues includes sub-basement membrane deposition of collagen, stromal deposition of extracellular matrix protein, and hypertrophy/hyperplasia of airway smooth muscle cells, which are relevant to the cellular and molecular events induced by platelet-derived growth factor (PDGF). Therefore, we investigated the localization of mRNA and protein of PDGF-B chain (PDGF-B) in NP tissues and bronchial tissues from mild and severe asthmatics by in situ hybridization and immunohistochemistry, respectively. Cells expressing PDGF-B mRNA were found in all nine NP tissues and in bronchial tissues from 2 of 6 normal subjects, 2 of 5 mild asthmatics, and all of 6 severe asthmatics examined. The vast majority of cells expressing PDGF-B mRNA were eosinophils in NP (99.7 +/- 0.2%, mean +/- SD) and asthmatic bronchial tissues (75.0 and 77.8% in mild asthma, and 92.7 +/- 8.1% in severe asthma), but no cells expressing PDGF-B mRNA were eosinophils in normal bronchial tissues. The number of cells expressing the gene in severe asthma tissues (122.3 +/- 32.2/mm2) was similar to that in NP tissues (152.8 +/- 73.9/mm2) and greater than that in mild asthma tissues (4.7 +/- 7.6/mm2, P < 0.01), which was not significantly greater than that in normal bronchial tissues (3.4 +/- 5.2/mm2). Furthermore, we detected immunolocalization of PDGF-B in NP tissues and in asthmatic bronchial tissues. The eosinophils purified from peripheral blood were demonstrated to express PDGF-B gene transcript and immunoreactivity after stimulation with A23187.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Postnatal development of lymphoid follicles in rat Peyer's patches, with special reference to increased follicle number.

The postnatal development of Peyer's patches was investigated using routine histological and immunohistochemical techniques, focusing especially on the formation and increase in number of lymphoid follicles. In addition, we studied the influence on the development of lymphoid follicles in Peyer's patches of a sublethal dose of whole-body X-irradiation at an earlier postnatal age. At 1 day after birth, surface-IgM (sIgM)-bearing cells (B lymphocytes) were scattered throughout the Peyer's patch. At Day 3, sIgM-bearing cells had accumulated to form primary follicles in association with domed elevations. OX2-positive reticular cells (FDC) were detected in the centers of primary follicles at Day 5. The first appearance of germinal centers within lymphoid follicles was noted at 18 days, and at 21 days almost every follicle contained a germinal center. At Day 5, each Peyer's patch contained 6-8 lymphoid follicles, with the lymphoid follicles subsequently increasing in size and number. The mean number of follicles per Peyer's patch became 11.1, the adult level, at 21 days, and remained at this level for the next 15 weeks, even though respective follicles continued to enlarge during the observation period. Three-week-old rats received 400 rad whole-body X-irradiation. At 3 and 7 days after treatment, lymphocytes were largely depleted from Peyer's patches, leaving behind the structural framework of the lymphoid follicles, interfollicular zones and domes. Stromal cells in the follicle remnants retained a positive reaction to OX2.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Lateral plate mesoderm and guidance cues for cutaneous nerve growth in the avian body wall.

Transplantation of the somatic layer of the lateral plate mesoderm (somatic mesoderm) was performed using the quail-chick chimera system in order to evaluate whether the connective tissue acts as guidance cues for the developing cutaneous nerve in the body wall. When quail somatic mesoderm at the sacro-coccygeal (pudendal) level was transplanted into the chick somatic mesodermal region at the thoracic level, the ventral nerve exhibited the pudendal type of branching pattern in the thoracic region. However, the cutaneous nerve course remained the thoracic type. These results suggest that the connective tissue derived from the somatic mesoderm provides cues for the determination of the nerve branching pattern. In contrast, the pathway selection might require other guidance cues than the somatic mesoderm in the ventral cutaneous nerve growth in the body wall.

Animals↗
PubMed1995

High-resolution SPECT to assess hippocampal perfusion in neuropsychiatric diseases.

UNLABELLED: The purpose of this study is to clarify the changes of hippocampal perfusion in neuropsychiatric diseases, including dementia, compared with control subjects, and to correlate hippocampal perfusion with the dementia rating scale and the severity of memory disturbance in patients with these diseases. METHODS: A total of 45 right-handed patients were investigated (13 with dementia of Alzheimer type, 6 with multi-infarct dementia, 4 with progressive dementia with motor neuron disease (MND), 3 with transient global amnesia, 5 with other diseases and 14 control subjects). Regional cerebral blood flow (rCBF) in the parietal cortex and hippocampus was evaluated by high-resolution SPECT technique with HMPAO in all subjects. RESULTS: The rCBF measurements in the bilateral parietal cortices and hippocampus were lower in dementia of Alzheimer type and multi-infarct dementia patients than in controls. Hypoperfusion in the hippocampus was a more sensitive marker than hypoperfusion in the parietal cortex in diagnosing dementia of Alzheimer type. Hippocampal hypoperfusion was observed in demented patients regardless of etiology and in patients having memory disturbance without dementia, such as transient global amnesia. Finally, hippocampal hypoperfusion reflected the severity of dementia and memory disturbance regardless of etiology. CONCLUSION: The rCBF image with high-resolution SPECT system may be useful in assessing the extent of dementia and memory disturbance in patients with neuropsychiatric diseases.

Adult↗
PubMed1995

Thallium-201 uptake in eosinophilic granuloma of the frontal bone: comparison with technetium-99m-MDP imaging.

An 11-yr-old female presented with a 6-wk history of left upper lid tenderness and left eye lacrimation. Left lateral supraorbital mass and left preauricular lymph node were the only significant physical examination findings. On skull x-ray, a left frontal bone defect was noted. CT and MRI showed a soft-tissue mass in the area of the bone defect. Bone scintigraphy exhibited peripheral uptake within the central photon deficient area. With 201TI SPECT, high uptake was noted on early and delayed images. Diagnosis of eosinophilic granuloma was performed by biopsy. Since thallium uptake was seen in the area where photon deficiency was exhibited by 99mTc-MDP scintigraphy, we speculate that thallium SPECT could detect eosinophilic granuloma when radiographic skeletal survey or radionuclide bone scan are equivocal. It could also rule out multiple bone involvement and recurrence or regrowth after therapy.

Child↗
PubMed1995

Crossed cerebellar diaschisis: analysis of iodine-123-IMP SPECT imaging.

UNLABELLED: The aim of this study was to review the etiology of CCD and study factors that affect the development and manifestation of CCD. METHODS: Three hundred and eleven patients with supratentorial lesions were evaluated for the presence of CCD with SPECT and 123I-IMP. In representative cases, continuous arterial blood sampling was done and rCBF was calculated using Kuhl's method. RESULTS: IMP-SPECT detected an abnormality in 206 patients, of whom 30 had CCD. Of CCD patients, 27 had more than single lobe involvement, 17 had motor impairment, 8 of 11 had rCBF of less than 29.1 +/- 10.9 ml/100 g/min. There was also a significant difference in rCBF between non-CCD and CCD cases. CONCLUSION: Although CCD can also occur with dementia (mixed or vascular type), it is more common with multilobar lesions. It is also associated with the presence of motor impairment but not related to its severity. It is more likely to develop, however, if rCBF is less than 29.1 +/- 10.9 ml/100 g/min regardless of etiology.

Amphetamines↗
PubMed1994

A severe outbreak of haemorrhagic colitis and haemolytic uraemic syndrome associated with Escherichia coli O157:H7 in Japan.

UNLABELLED: In 1990, an outbreak of Escherichia coli O157:H7 infection occurred in 174 children in a nursery school in Saitama, Japan. The organism was isolated from tap water supplied from the well in the school. Clinical manifestations varied from asymptomatic infection to non-bloody diarrhoea, haemorrhagic colitis, haemolytic uraemic syndrome (HUS) and death. Among culture-confirmed 42 cases of E. coli O157:H7, 7 children were asymptomatic, 21 children had only diarrhoea, and 14 children developed HUS. Bloody diarrhoea with abdominal pain following initial frequent diarrhoea appeared to be associated with subsequent HUS. In patients with HUS, both leucocyte count and lactate dehydrogenase activity continued to increase in the early phase of the disease, and on day 3 of illness attained markedly higher levels than in patients without HUS. These two parameters seemed to be important as predictors of the development of HUS. CONCLUSION: E. coli O157:H7 is a common pathogen causing colitis. It should be kept in mind in paediatric practice and public health.

Child↗
PubMed1994

Cardiac involvement of progressive muscular dystrophy (Becker type, Limb-girdle type and Fukuyama type) evaluated by radionuclide method.

Tl-201 SPECT and Tc-99m-Human serum albumin (HSA) multigated radionuclide ventriculography were performed on 11 patients with progressive muscular dystrophy (Becker type 2, Fukuyama type 2, Limb-girdle type 7) to evaluate myocardial involvement. Hypoperfusion was detected in 8 patients on Tl-201 SPECT. Decreases in both systolic function (left ventricular ejection fraction; LVEF) and diastolic function (peak filling rate; PFR) were also seen in these patients. A high incidence of myocardial involvement of these kinds of progressive muscular dystrophy was suggested.

Adolescent↗
PubMed1994

Self-expanding metal stents for palliative treatment of malignant biliary and duodenal stenoses.

Patients with malignant biliary stenosis due to pancreatic head cancer often have the associated problem of duodenal obstruction. We report here the case of a 78-year-old woman with this clinical situation, who was treated with self-expanding Gianturco metal stents placed in the distal common bile duct and, nine months later, placed in the descending duodenum. The patient's frequent vomiting resolved, and she was able to tolerate peroral solid food; jaundice also decreased (bilirubin pre-stenting: 7.8; post-stenting: 1.2). Self-expanding metal stents therefore appear to be effective for the palliative treatment of malignant duodenal stenosis as well as biliary stenosis.

Aged↗
PubMed1994

Work environment of plants manufacturing asbestos-containing products in Japan.

In 1985, a comprehensive study of asbestos-containing product plants (A/C, friction, textile) was performed. The data presented were based not on personal but on area sampling. A conversion equation from area sampling data to personal exposure values was developed. Exposure concentrations were 0.07-0.66 f ml-1. In workplaces which belonged to member companies of the Japan Asbestos Association, the percentage of workplaces whose exposure concentrations was less than 0.3 f ml-1 was 70% in 1985 (N = 510), but 98% in 1992 (N = 430). Concentrations in a new, well-controlled A/C plant were less than 0.1 f ml-1.

Asbestos↗
PubMed1994

Tissue inhibitor of metalloproteinases (TIMP-1) produced by granulosa and oviduct cells enhances in vitro development of bovine embryo.

Embryogenesis-stimulating activity (ESA) was found in serum-free conditioned media (CM) of bovine cumulus/granulosa cells (BGC) and bovine oviductal epithelial cells (BOEC). The CM of BGC (BGC-CM) contained two molecular species of ESA, one with a low molecular weight (M(r) 30,000) and another with a high molecular weight (M(r) 80,000); but only the activity with low molecular weight was detected in CM of BOEC by gel-permeation chromatography. The smaller ESA (embryogenin-1) in BGC-CM was purified to homogeneity, as a common activity in both CM by a combination of gel-permeation chromatography, ion-exchange chromatography, and reverse-phase HPLC. Embryogenin-1 has a molecular weight of 31,100 (reduced) and has been identified as a bovine tissue inhibitor of metalloproteinase-1 by NH2-terminal amino acid sequence analysis. Western blot analysis, anti-proteinase activities against metalloproteinases, and the nucleotide sequence of cDNA isolated from a lambda gt11 cDNA library of the bovine ovary by a polyclonal antibody against embryogenin-1. These data suggest that the tissue inhibitor of metalloproteinase-1 produced by BGC and BOEC is a major ESA for in vitro development of bovine embryos.

Amino Acid Sequence↗