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A Yamauchi

Publications and source records attributed to A Yamauchi.

At least 19 recordsLinked to original sources
PubMed2006

Glucocorticoid-induced diabetes mellitus: prevalence and risk factors in primary renal diseases.

BACKGROUND/AIMS: In patients with primary renal diseases the current knowledge of hyperglycemia associated with corticosteroid therapy is limited. We therefore examined the prevalence and risk factors of glucocorticoid-induced diabetes mellitus (DM) in primary renal diseases. METHODS: Patients were recruited with primary renal diseases who were started on corticosteroids between April 2002 and June 2005. In patients with DM, an impaired fasting glucose level and/or positive urinary glucose analyses before corticosteroids therapy were excluded. RESULTS: During corticosteroid therapy (initial dose: prednisolone 0.75 +/- 0.10 mg/kg/day), DM was newly diagnosed in 17 (40.5%) of 42 patients. All of the 17 patients were diagnosed as having DM by postprandial hyperglycemia at 2 h after lunch, although they had normal fasting blood glucose levels. Age (OR 1.40, 95% CI 1.06-1.84) and body mass index (OR 1.87, 95% CI 1.03-3.38) were determined as independent risk factors for glucocorticoid-induced DM. CONCLUSION: Over 40% of patients with primary renal disease developed DM during treatment with corticosteroids. A high age and high body mass index are the independent risk factors for glucocorticoid-induced DM. 24-hour urinary glucose analyses and postprandial plasma glucose are useful for detecting glucocorticoid-induced DM.

Adult↗
PubMed2006

Pathology of fatal highly pathogenic H5N1 avian influenza virus infection in large-billed crows (Corvus macrorhynchos) during the 2004 outbreak in Japan.

Highly pathogenic H5N1 avian influenza viruses were isolated in 9 large-billed crows that died in Kyoto and Osaka prefectures in Japan from March to April in 2004. We studied 3 of the 9 crows using standard histologic methods, immunohistochemistry, and virus isolation. The most prominent lesions were gross patchy areas of reddish discoloration in the pancreas. The consistent histologic lesions included severe multifocal necrotizing pancreatitis, focal degeneration and necrosis of neuron and glial cells in the central nervous system, and focal degeneration of cardiac myocytes. All of these tissues contained immunohistochemically positive influenza viral antigens. The virus was isolated from the brain, lung, heart, liver, spleen, and kidney of the crows examined. Thus we concluded that highly pathogenic avian influenza virus was associated with clinical disease, severe pathologic changes, and death in the 3 crows.

Animals↗
PubMed2005

[Prevention of acute exacerbation of interstitial pneumonia in the patients operated for lung cancer].

Eight patients with interstitial pneumonia (IP) underwent pulmonary surgery for lung cancer. The first patient died due to postoperative exacerbation, but the subsequent 7 patients had good postoperative course without exacerbation by the following careful management. 1) Avoidance of administration of high concentration of oxygen keeping the PO2 about 100 mmHg during the operation. 2) Short-term administration of low-dose steroid before the operation. 3) Administration of erythromycin, tocopherol acetate, and inhalation of N-acetylcysteine before and after the operation. 4) Long-term drainage of the postoperative thoracic discharge to release the local cytokines. These treatments inhibit secretion of the inflammatory cytokines which influence exacerbation of IP.

Aged↗
PubMed2004

Autoantibodies to REG, a beta-cell regeneration factor, in diabetic patients.

BACKGROUND: Regenerating gene (Reg) product, Reg, acts as an autocrine/paracrine growth factor for beta-cell regeneration. The presence of autoimmunity against REG may affect the operative of the regenerative mechanisms in beta cells of Type 1 and Type 2 diabetes patients. We screened sera from Type 1 and Type 2 diabetes subjects for anti-REG autoantibodies, searched for correlations in the general characteristics of the subjects with the presence of anti-REG autoimmunity, and tested the attenuation of REG-induced beta-cell proliferation by the autoanitibodies. MATERIAL AND METHODS: We examined the occurrence of anti-REG autoantibodies in patients' sera (265 Type 1, 368 Type 2 diabetes patients, and 75 unrelated control subjects) by Western blot analysis, and evaluated inhibitory effects of the sera on REG-stimulated beta-cell proliferation by a 5'-Bromo-2'-deoxyuridine (BrdU) incorporation assay in vitro. RESULTS: Anti-REG autoantibodies were found in 24.9% of Type 1, 14.9% of Type 2 and 2.7% of control subjects (P = 0.0004). There were significant differences between the autoantibody positive and negative groups in the duration of disease in the Type 1 subjects (P = 0.0035), and the age of onset in the Type 2 subjects (P = 0.0274). The patient sera containing anti-REG autoantibodies significantly attenuated the BrdU incorporation by REG (35.6 +/- 4.06% of the control), whereas the nondiabetic sera without anti-REG autoantibodies scarcely reduced the incorporation (88.8 +/- 5.10%). CONCLUSION: Anti-REG autoantibodies, which retard beta-cell proliferation in vitro, are found in some diabetic patients. Thus, autoimmunity to REG may be associated with the development/acceleration of diabetes in at least some patients.

Adolescent↗
PubMed2004

[Surgical treatment of traumatic disruption of the thoracic aorta due to fall from 6 meters height tree; report of a case].

Disruption of the thoracic aorta due to blunt chest trauma is highly lethal and requires emergent operative intervention. A successful operative treatment of traumatic disruption of the thoracic aorta is reported. A 44-year-old male was admitted to our hospital following a fall from 6 m height tree. Four hours after accident, chest X-ray film demonstrated mediastinal widening. Chest helical computed tomography (CT) scanning demonstrated mediastinal hematoma, left pleural effusion and partial descending aortic dissection. Aortic disruption was diagnosed, and surgery for the thoracic aorta was performed emergently. The 2/3 of circumferentia of the aorta was found to be disrupted in the length of 2 cm, and it was replaced with a vascular prosthesis under partial cardiopulmonary bypass. We conclude that the enhanced chest helical CT scanning is helpful for diagnosis and that if other organ injuries are not critical, the emergent surgery should be required.

Accidental Falls↗
PubMed2004

[Removal of the intrapleural hematoma after extrapleural pneumonectomy].

Three cases of pleuropneumonectomy, which have been performed in our institution between 1996 and 2003, are studied. All of them received re-thoracotomy to remove intrapleural hematoma for prolonged high fever, anemia and high level of CRP. Post re-operative courses were satisfactory without any signs of infection. The residual intrapleural hematoma sometimes causes pyothorax and would be an obstacle to the intrapleural instillation of anticancer medications. The removal of the hematoma should be scheduled at an early period after the pleuropneumonectomy.

Hematoma↗
PubMed2002

Nasal glucagon delivery using microcrystalline cellulose in healthy volunteers.

We developed an intranasal powder form of glucagon to improve metabolic status and fatty liver in patients with pancreatectomy. Microcrystalline cellulose, which is commonly used in commercial preparations for allergic rhinitis was used as an absorption enhancer. We compared the intranasal powder form with some spray solutions of glucagon with regard to glucagon absorption, concentration of blood glucose, stability and nasal irritation. The absorption of glucagon from the spray solution including 1.5% sodium glycocholate or 1% sodium caprate was 1.3- and 2.6-fold higher than that from the powder form mixed with microcrystalline cellulose at a ratio of 1:69, respectively. The C(max) values of plasma glucose were 2.18, 3.39 and 1.56 mmol l(-1) in the spray solutions including sodium glycocholate and sodium caprate and in the powder form, respectively. However, glucagon in spray solutions was unstable, but that in the powder form was stable at 5 and 25 degrees C for at least 84 days. The spray solution caused strong irritation, but the powder form did not. These results suggested usefulness of the powder form of glucagon for treatment of pancreatectomized patients.

Administration, Intranasal↗
PubMed2002

Relationship between inner-ear fluid pressure and semicircular canal afferent nerve discharge.

The present study was designed to determine (1) the transcupular fluid pressure (deltaP) generated across the semicircular canal cupula in response to sinusoidal head rotation, (2) the translabyrinthine dilational pressure (P0) generated across the membranous labyrinth in response to an increase in endolymph fluid volume (hydrops), (3) afferent nerve discharge patterns generated by these distinct pressure stimuli and, (4) threshold values of deltaP and P0 required to elicit afferent neural responses. The experimental model was the oyster toadfish, Opsanus tau. Micromechanical indentation of the horizontal canal (HC) duct and utricular vestibule was used to simulate sinusoidal head rotation and fluid volume injection. Single-unit neural spike trains and endolymph pressure within the ampulla, on both sides of the cupula, were recorded simultaneously. deltaP averaged 0.013 Pa per 1 degrees/s of sinusoidal angular head velocity and P0 averaged 0.2 Pa per 1 nL of endolymph volume injection. The most responsive afferents had a threshold sensitivity to deltaP of 10(-3) Pa and to P0 of 5 x 10(-2) Pa based on a discharge modulation criterion of 1 impulse/s per cycle for 2 Hz pressure stimuli. Neural sensitivity to AP was expected on the basis of transverse cupular and hair bundle deflections. Analysis of mechanics of the end organ, neuronal projections into the crista, and individual neural firing patterns indicates that P0 sensitivity resulted from pressure-induced distension of the ampulla that led to a nonuniform cupular deformation pattern and hair bundle deflections. This explanation is consistent with predictions of a finite element model of the end organ. Results have implications regarding the role of deltaP in angular motion transduction and the role of P0 under transient hydropic conditions.

Action Potentials↗
PubMed2002

[Anomalous systemic arterial supply to normal basal segment of the left lower lobe; report of a case].

A 28-year-old male was referred to our hospital because of hemoptysis. A chest X-ray revealed an increase of vascular marking in the left lower field and a partial defect in the lateral line of the descending thoracic aorta. An aortogram and pulmonary arteriogram showed a large artery arising from the descending thoracic aorta and supplying the left basal segment, which had no normal pulmonary arteries. A bronchoscopy showed no abnormal findings in the bronchial tree. A clinical diagnosis of systemic arterial supply to the basal segment of the left lower lung was made, and a left lower lobectomy and closure of the anomalous systemic artery by video-assisted thoracic surgery (VATS) were successfully performed. Vascular marking of the visceral pleura of left lower basal segment was observed and the anomalous arterial pressure was 84 mmHg, as high as systemic arterial pressure, during the procedure. The histopathological examination revealed normal alveolar structure, and sclerosis and hypertrophy of pulmonary arteries of the lesion (Heath-Edwards V, which means irreversible vascular changes due to pulmonary hypertension). The patient had an uneventful postoperative course and was discharged on postoperative day 8. The VATS procedure is a more useful and less invasive method for cases of systemic arterial supply to the basal segment of the left lower lung than an open thoracotomy.

Adult↗
PubMed2002

[Clinical study of eight thymic carcinomas].

Eight patients with thymic carcinoma were surgically treated at Sapporo City General Hospital from September 1990 to January 2002. The histological subtypes of thymic carcinoma were squamous cell in 5, undifferentiated in 2, and small cell in one. After median sternotomy, 5 patients had total resection of the tumor, and 3 had incomplete resection due to extensive mediastinal invasion involving the main pulmonary artery in the A-P window. Of 3 cases with intra pericardial malignant effusion, one patient survived 7 years without recurrence of the tumor after the exploratory operation followed by mediastinal irradiation without chemotherapy. In this patient, existence of the malignant cells in the pericardial effusion was not associated with poor outcome.

Adult↗
PubMed2001

The intratumoral expression of vascular endothelial growth factor and interleukin-8 associated with angiogenesis in nonsmall cell lung carcinoma patients.

BACKGROUND: Angiogenesis has important effects on tumor growth and metastasis. It is regulated by a variety of angiogenic and angiostatic factors. METHODS: To evaluate the effects of tumor cell-derived angiogenic factors, we performed an immunohistochemic study to evaluate the intratumoral expression of vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) in relation to intratumoral microvessel density (IMD) in tumors from 104 nonsmall cell lung carcinoma (NSCLC)patients. RESULTS: Fifty-four carcinomas were VEGF-positive, 47 carcinomas were IL-8-positive, and 53 carcinomas were hypervascular tumors. There was no significant correlation between the percentages of positive VEGF-staining and positive IL-8-staining in NSCLCs (rho = 0.174, P = 0.080). The IMD of VEGF-positive carcinomas was significantly greater than that of VEGF-negative carcinomas (P = 0.023). In addition, the IMD of IL-8-positive carcinomas was significantly greater than that of IL-8-negative carcinomas (P =0.013). The overall survival rate of patients with hypervascular tumors was significantly lower than that of patients with hypovascular tumors (41.0% versus 67.0%, P = 0.004). Cox proportional-hazards regression model also demonstrated that angiogenesis was one of the significant factors in predicting the survival of NSCLC patients (relative risk = 1.944, P = 0.041). CONCLUSIONS: Intratumoral expression of VEGF and IL-8 was associated with angiogenesis in NSCLCs. Tumor angiogenesis significantly affected the prognosis of NSCLC patients.

Adult↗
PubMed2001

Ovariectomy aggravates convulsions and hippocampal gamma-aminobutyric acid inhibition induced by cyclosporin A in rats.

The possible cyclosporin A application for rheumatoid arthritis that develops preferentially in middle-aged women raises concerns about adverse effects of cyclosporin A, including neurotoxicity in patients with climacterium. The present study was aimed at elucidating the effect of cyclosporin A on the convulsive activity and gamma-aminobutyric acid (GABA) neural activity of the hippocampus in ovariectomized rats, as a menopause/climacterium model. Ovariectomy markedly aggravated the effect of repeated administration of cyclosporin A (40 mg/kg, once a day for 5 or 6 days), convulsions and reduction of the basal GABA levels and aminooxyacetic acid-evoked GABA accumulation. These aggravations were blocked by estradiol replacement. The present findings demonstrated that ovariectomy increased the susceptibility to cyclosporin A-induced convulsions by accelerating an inhibitory action of cyclosporin A on GABA neural activity in the hippocampus, this being blocked by estrogen replacement. Menopause/climacterium is, therefore, included in the risk factors for cyclosporin A-induced neurotoxicity and this risk is lowered by estrogen replacement therapy.

Aminooxyacetic Acid↗
PubMed2001

Boronic acid fluorophore/beta-cyclodextrin complex sensors for selective sugar recognition in water.

A novel boronic acid fluorophore 1/beta-cyclodextrin (beta-CyD) complex sensor for sugar recognition in water has been designed. The probe 1 bearing pyrene moiety as a fluorescent signal transducer exhibits no fluorescence emission, due to its aggregation in water containing 2% DMSO; however, the addition of beta-CyD to this solution largely changes UV-vis and fluorescence spectra of 1 by forming an inclusion complex with beta-CyD, and an efficient fluorescence emission response of 1/beta-CyD complex upon sugar binding is found to be obtained at pH 7.5. The pH-fluorescence profile of the 1/beta-CyD complex reveals that the boronate ester formation with fructose induces the apparent pKa shift from 7.95+/-0.03 in the absence of fructose to 6.06+/-0.03 in the presence of 30 mM fructose, resulting in the fluorescence emission response under the neutral condition. The spectral properties of 1 in 95% methanol:5% water (v/v), as well as the fluorescence quenching study of 1-methylpyrene with 4-methoxycarbonylphenyl-boronic acid 2, demonstrate that the response mechanism is based on the photoinduced electron transfer (PET) from the pyrene donor to the acid form of phenylboronic acid acceptor in 1, and thus, the proton dissociation of phenylboronic acid induced by sugar binding inhibits the PET system while increasing the fluorescence intensity of the pyrene moiety. To evaluate the binding ability and selectivity of the 1/beta-CyD complex for monosaccharides in water, the response equilibria have been derived. The 1:1 binding constants of the 1/beta-CyD complex obtained from the equilibrium analysis are in the order: D-fructose (2515+/-134 M(-1)) >> L-arabinose (269 +/- 28 M(-1)) > D-galactose (197+/-28 M(-1)) > D-glucose (79+/-33 M(-1)), which is consistent with the binding selectivity of phenylboronic acid.

Journal Article↗
PubMed2001

Lymphoproliferative disorders in renal transplant patients in Japan.

Post-transplantation lymphoproliferative disorders (PT-LPD) are characterized by a clinically and morphologically heterogeneous group of lymphoid proliferation occurring after organ or bone marrow transplantation. The immunodeficient state provides a basis for lymphomagenesis probably through activation of oncogenic viruses. Twenty-four patients in whom PT-LPD developed after renal transplantation in Japan were analyzed. They received hemodialysis for 4 to 226 (median 13) months before transplantation. In situ hybridization was performed to detect Epstein-Barr virus (EBV). Polymerase chain reaction and Southern hybridization with primers in the tax and pol regions of human T-cell leukemia virus type I (HTLV-1) were performed on DNA extracted from paraffin-embedded specimens. Immunohistochemical analysis revealed that 12 cases were B-cell type, 10 cases (42%) T-cell type and 2 NK-cell type. Five of the T-cell cases were classified as adult T-cell lymphoma with proven HTLV-1 genome in the tumor and seropositivity for the virus. These cases were classified as adult T-cell lymphoma (ALT). More than 80% of B-cell, 30% of T-cell and both NK/T-cell lymphomas were EBV-positive. Co-infection of EBV and HTLV-1 was found in 2 cases with ATL. These findings showed that ATL is common among Japanese renal transplant patients, which might be due to transmission of HTLV-1 via blood transfusion during hemodialysis.

Adolescent↗
PubMed2001

Comparative evaluation of 99mTc-MIBI and 99mTc-HMDP scintimammography for the diagnosis of breast cancer and its axillary metastases.

The purpose of the present study was to compare scintimammography using technetium-99m hexakis 2-methoxyisobutylisonitrile (MIBI) with that using 99mTc-hydroxymethylene diphosphonate (HMDP) in the detection of breast cancer and its axillary lesions. The study population comprised 50 consecutive females with breast cancer who were scheduled for surgery. All patients underwent scintimammography with 99mTc-MIBI and 99mTc-HMDP. The images were acquired 5 min (early) and 2 h (delayed) after injection of each radiopharmaceutical. Regions of interest were placed over the breast tumour (T), the axillary lesion (A) and the normal ipsilateral breast tissue (N). The two count ratios were calculated, i.e. the tumour to normal breast tissue ratio (T/N) and the axillary lymph node to normal breast tissue ratio (A/N). For the breast tumours, using 99mTc-MIBI the positive rate was 86% (43/50) for the early and 72% (36/50) for the delayed images. The corresponding values using 99mTc-HMDP were 72% (36/50) and 40% (20/50), respectively. Histopathological examination revealed metastatic lymph node involvement in 22 patients. For the axillary lesions, using 99mTc-MIBI the positive rate was 72.7% (16/22) for the early and 54.5% (12/22) for the delayed images. Using 99mTc-HMDP, the positive rate was only 18.2% (4/22) for the early and 4.5% (1/22) for the delayed images. Using 99mTc-MIBI, the mean T/N (+/- SD) ratios on early and delayed images were 2.69 +/- 1.64 and 2.03 +/- 1.16, respectively, and the mean A/N (+/- SD) ratios on early and delayed images were 2.20 +/- 1.23 and 1.80 +/- 1.20, respectively. The corresponding values using 99mTc-HMDP were 1.77 +/- 0.91, 1.42 +/- 0.72, 1.27 +/- 0.63 and 1.08 +/- 0.25, respectively. The T/N and A/N ratios on the early and delayed 99mTc-MIBI images were both significantly higher than those obtained using 99mTc-HMDP. 99mTc-MIBI scintimammography is more sensitive than 99mTc-HMDP scintimammography for the detection of breast cancer and its axillary lymph node metastases.

Adult↗
PubMed2001

Malignant adenomyoepithelioma of the breast with lung metastases: report of a case.

Adenomyoepithelioma of the breast is a rare lesion, and has a bicellular pattern of epithelial and myoepithelial cells which are regularly distributed in the tubular structures based on the histologic and ultrastructural features. It is thought to be a benign or a low-grade malignant disease. We herein describe a case of malignant adenomyoepithelioma of the breast with lung metastases in an 86-year-old woman. A primary massive tumor in the left breast grew rapidly within a short period of time. A simple mastectomy with sampling of the axillary lymph nodes was performed. The obtained lymph nodes did not include any metastatic lesions. Malignancy was evidenced by the presence of a high mitotic rate and severe nuclear atypia. Three months after the operation, radiology showed multiple lung metastases, and the patient died 2 weeks thereafter. Reviewing the literature, nine similar cases were reported, and the prognosis of malignant adenomyoepithelioma of the breast with distant metastases was very poor with the time of recurrence varying after initial treatments. Malignant adenomyoepithelioma should be followed up with careful screening for distant metastases.

Aged↗