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M Yamakido

Publications and source records attributed to M Yamakido.

At least 37 records · Page 2Linked to original sources
PubMed2000

Stimulation of tumour necrosis factor-alpha production by recombinant human erythropoietin may contribute to failure of therapy.

Although the mechanism of unresponsiveness to recombinant human erythropoietin therapy in dialysis patients has been studied extensively in recent years, many aspects remain unclear. We previously found that administration of erythropoietin induces interleukin-1beta, a cytokine that inhibits erythropoiesis. The present study investigated the involvement of tumour necrosis factor-alpha, another cytokine which inhibits erythropoiesis. Peripheral blood mononuclear cells were obtained from 18 patients on continuous ambulatory peritoneal dialysis, who were being treated with erythropoietin for renal anaemia, and were cultured with various concentrations of erythropoietin (0, 1, 5, 10, and 50 U/ml). Then the tumour necrosis factor-alpha level in the culture supernatant was assayed. The 18 patients were divided into four groups on the basis of the haematocrit after treatment: group A (n = 3), <23.0%; group B (n = 5), 23.0-24.9%; group C (n = 7), 25.0-26.9%; and group D (n = 3), > or =27.0%. In group A, the tumour necrosis factor-alpha level in the culture supernatant was increased by incubation with erythropoietin, while it was not increased in other groups. The tumour necrosis factor-alpha level was significantly higher in group A than in the other groups at erythropoietin concentrations of 5 U/ml. These results suggested that induction of tumour necrosis factor-alpha is one of the reasons for unresponsiveness to recombinant human erythropoietin.

Adult↗
PubMed2000

Inhibitory effects of a lecithinized superoxide dismutase on bleomycin-induced pulmonary fibrosis in mice.

Oxidant/antioxidant imbalance is thought to be involved in the pathogenesis of idiopathic pulmonary fibrosis (IPF). Therefore, antioxidants, such as superoxide dismutase (SOD), are expected to have an inhibitory potential against IPF. To elucidate whether a lecithinized SOD (phosphatidylcholine [PC]-SOD) has the potential to be a new therapeutic agent for IPF, we investigated the inhibitory effects of PC-SOD at doses of 1 mg/kg/d (low dose) and 10 mg/kg/d (high dose) and of methylprednisolone (mPSL) on bleomycin (BLM)-induced pulmonary fibrosis in mice. Histopathologic evaluation and lung hydroxyproline content revealed that the severity of fibrosis was attenuated in mice treated with low-dose PC-SOD, whereas no significant effect was observed in other mice. In bronchoalveolar lavage fluid on Day 1 after treatment with BLM, BLM-induced increases in total cell number, populations of lymphocytes and neutrophils, and expression of messenger RNA for interleukin-1beta and platelet-derived growth factor (PDGF)-A were significantly suppressed in PC-SOD-treated mice. The suppression of PDGF-A expression was significantly greater in mice treated with low-dose PC-SOD than in mice treated with high-dose PC-SOD or mPSL. In summary, this study demonstrated the inhibitory effects of low-dose PC-SOD on the development of pulmonary fibrosis, which indicates the potential usefulness of PC-SOD as a new treatment agent for IPF or at least for BLM-induced pulmonary fibrosis in humans.

Animals↗
PubMed2000

Implantation of ultraflex nitinol stents in malignant tracheobronchial stenoses.

STUDY OBJECTIVE: To assess the uncovered Ultraflex nitinol stent (Boston Scientific; Natick, MA) for its efficacy and safety. DESIGN, SETTING, AND PATIENTS: Between October 1997 and October 1998, we carried out a prospective multicenter study at six hospitals in Japan. Fifty-four Ultraflex stents were inserted in 34 patients with inoperable malignant airway stenosis using a flexible and/or a rigid bronchoscope under fluoroscopic and endoscopic visualization. MEASUREMENTS AND RESULTS: Clinical, endoscopic examination, and pulmonary function on days 1, 30, and 60 after stent implantation showed improvement. In 19 patients (56%), stent implantation was performed as an emergency procedure because of life-threatening tracheobronchial obstruction. Immediate relief of dyspnea was achieved in 82% of the patients. The dyspnea index improved significantly after implantation (before vs. days 1, 30, and 60; p<0.001). Significant improvements were observed in obstruction of airway diameter (81+/-15% before vs. 14+/-17% on day 1, 12+/-12% on day 30, and 22+/-28% on day 60; p<0.001). Vital capacity (VC), FEV(1), and peak expiratory flow (PEF) increased significantly after stent implantation: before vs immediately after VC (p<0.01), FEV(1) (p<0.001), and PEF (p<0.05). The main complications were tumor ingrowth (24%) and tumor overgrowth (21%). After coagulation with an Nd-YAG laser or argon plasma coagulation, mechanical coring out using the bevel of a rigid bronchoscope was necessary in patients showing tumor ingrowth or overgrowth. Removal and reposition were possible in case of misplacement. There were no problems with migration and retained secretions. The median survival time of patients was 3 months. The 1-year survival rate was 25.4%. CONCLUSIONS: In this study of the Ultraflex nitinol stent, we have demonstrated that patients were relieved from dyspnea, which contributed to improved quality of life, with minimal complications. This stent can be used safely, even in the subglottic region. Owing to its excellent flexibility and biocompatibility, the stent is also indicated in certain complicated situations, eg, narrow stenosis, hourglass stenosis, curvilinear stenosis, bilateral mainstem bronchial stenoses, and long stenosis of varying diameters.

Adult↗
PubMed2000

Clinical experiences of stenting in patients with esophago-bronchial fistula: report of four cases.

The esophagorespiratory fistula is difficult to treat, and the patients' quality of life is generally poor due to suffering from dysphagia and dyspnea. We performed stent therapy in four cases of the esophagorespiratory fistula associated with esophageal cancer. Three of four patients showed improved symptoms, enabling oral liquid or food intake, although one died of dyspnea despite the therapy. The findings suggest that stent therapy is an effective method to close the esophagorespiratory fistula and to improve the patients' quality of life, although it is temporary and not a radical treatment.

Aged↗
PubMed2000

Psoriatic arthritis complicating lung cancer.

Psoriatic arthritis is an inflammatory arthritis associated with psoriasis. While an elevated incidence of lung cancer has been observed in patients with RA or psoriasis, there has been no report of psoriatic arthritis associated with lung cancer. We here report the first case of psoriatic arthritis which developed lung cancer. In this case, it was suspected that a combination of cigarette smoking, pulmonary fibrosis, and low-dose methotrexate therapy might have promoted the development of lung cancer.

Aged↗
PubMed2000

Clinical evaluation of idiopathic interstitial pneumonia and interstitial pneumonia associated with collagen vascular disease using logistic regression analysis.

OBJECTIVE: To clarify the differences in the clinical features between idiopathic interstitial pneumonia (IIP) and interstitial pneumonia associated with collagen vascular diseases (CVD-IP). METHODS: Symptoms, radiographic findings, pulmonary function, blood chemistry data including autoantibody, and bronchoalveolar lavage fluid (BALF) findings were compared using multiple logistic regression analysis. PATIENTS: The subjects were 44 patients clinically diagnosed with IIP and 33 patients with CVD-IP. RESULTS: The clinical features related to IIP were as follows: male sex, advanced age, past history of hypertension, presence of cough, exertional dyspnea, digital clubbing, an increased level of gamma-globulin, decreased lung volume on chest X-ray, and typical type according to the criteria for IIP on chest X-ray. Increased levels of rheumatoid factor and total cell number in BALF were related to CVD-IP. CONCLUSION: These findings are considered to be useful to differentiate IIP and CVD-IP.

Adult↗
PubMed2000

Successful treatment of systemic lupus erythematosus and pulmonary hypertension with intravenous prostaglandin I2 followed by its oral analogue.

Systemic lupus erythematosus (SLE) is sometimes reported to complicate fatal pulmonary hypertension. A 46-year-old woman, with a ten-year history of SLE and pulmonary hypertension, was admitted to our hospital complaining of dyspnea and chest pain. She suffered pulmonary hemorrhage and after steroid pulse therapy, she underwent continuous intravenous infusion of epoprostenol (prostaglandin I2) with corticosteroid for four weeks, which reduced the pulmonary artery pressure and resistance. Following the successful treatment, beraprost sodium, an oral PGI2 analogue, was given and it maintained pulmonary hypertension remittance for four years.

Administration, Oral↗
PubMed2000

An autopsy case of diffuse panbronchiolitis associated with lung cancer.

The prognosis of diffuse panbronchiolitis (DPB) has been remarkably improved after the development of low-dose erythromycin therapy, possibly due to anti-inflammatory rather than anti-infective mechanisms. Interestingly, DPB associated with lung cancer is quite rare. Here, we report an autopsy case of DPB who developed lung cancer after a long successful therapy with low-dose erythromycin.

Adenocarcinoma↗
PubMed2000

A family with cases of adult onset Still's disease and psoriatic arthritis.

Adult onset Still's disease is recognized as an adult variant of the systemic form of juvenile rheumatoid arthritis, whose disease-predisposition is still debated. On the other hand, the association between HLA subtypes and several groups of seronegative arthritis including psoriatic arthritis has been well documented. This report describes a family where adult onset Still's disease in a young man and psoriatic arthritis in his father were seen. Both patients were HLA-B39-positive, which was likely playing important pathogenic roles in the latter case. Clinical and immunological aspects of HLA-B39-related inflammatory diseases are also discussed.

Adult↗
PubMed2000

Microsomal epoxide hydrolase genotypes and chronic obstructive pulmonary disease in Japanese.

Polymorphisms in the gene for microsomal epoxide hydrolase (mEPHX), an enzyme involved in the protective mechanism against oxidative stress, have been reported to be associated with individual susceptibility to the development of chronic obstructive pulmonary disease (COPD). The polymorphisms in exons 3 and 4 in the mEPHX gene were examined in a total of 358 Japanese individuals, including 40 patients with COPD and 71 patients with lung cancer. The overall frequencies of variant allele for mEPHX codons 113 (exon 3) and 139 (exon 4) were 44% and 14%, respectively. Moreover, a novel single nucleotide polymorphism (estimated allele frequency: 0.29) was identified in Japanese at 20 bp downstream of the codon 113 polymorphism with strong linkage disequilibrium with the wild allele for codon 113. While the frequencies of variant allele and proportions of individuals homozygous variant for codon 113, assumed having very slow mEPHX activity, were similar among COPD or lung cancer patients and the control population, they were significantly higher in patients with severe COPD than in those with mild COPD [P=0.0225, odds ratio 2.9 (95%CI 1.1-7.4); P=0.0350, respectively]. Thus, we found that the frequency of the variant allele for mEPHX codon 113 is higher in Japanese than that in Caucasians (P=0.0028), a novel silent polymorphism exists in exon 3 and shows strong linkage disequilibrium with the wild allele for codon 113, and individual homozygous variants for codon 113 may be associated with development of advanced COPD rather than the susceptibility to COPD.

Adult↗
PubMed2000

p53 gene mutations are associated with shortened survival in patients with advanced non-small cell lung cancer: an analysis of medically managed patients.

Mutations in the p53 gene are common in many cancers. Nevertheless, the relationship between mutations of this tumor suppressor gene and patient survival in non-small cell lung cancer (NSCLC) remains unclear. Interpretation of prior studies of patient outcomes are complicated by the inclusion of both surgical and nonsurgical patients. To better isolate the potential effects of p53 gene mutations per se on tumor progression, we chose to examine patients with advanced disease in whom surgery was not performed (stages IIIA, IIIB, and IV). We have used PCR-denaturing gradient gel electrophoresis, a sensitive and specific method for the detection of a variety of p53 mutations in cytology or biopsy specimens, to evaluate the prognostic significance of p53 gene mutations in nonsurgical patients with advanced NSCLC. In 70 consecutive medical patients, p53 mutations were found in 29 cases (41%) at the time of initial diagnosis. Followed prospectively, patients with p53 mutations had a significantly reduced survival time after diagnosis than those without mutations (median survival, 17 versus 39 weeks; P = 0.0003) independent of other clinical factors. This abbreviated survival occurred in both patients who received chemotherapy (n = 39, P = 0.002) or best supportive care (n = 31, P = 0.018). These results indicate that mutations of the p53 gene in patients with NSCLC who do not undergo surgical resection portends a significantly worse prognosis.

Adult↗
PubMed2000

A case of CREST syndrome and myeloperoxidase-specific anti-neutrophil cytoplasmic autoantibody-associated glomerulonephritis.

We report the first case of myeloperoxidase-specific anti-neutrophil cytoplasmic autoantibody (MPO-ANCA)-associated glomerulonephritis in a patient with CREST syndrome. A 74-year-old Japanese man with CREST syndrome (calcinosis, Raynaud's phenomenon, esophageal dysfunction, sclerodactyly, and telangiectasia) developed rapidly progressive renal failure without elevation of blood pressure. Renal biopsy revealed glomerular sclerosis and fibrous crescents. The MPO-ANCA titer was elevated to 145 EU/ml. When patients with collagen diseases develop rapidly progressive glomerulonephritis, the possibility of MPO-ANCA-associated glomerulonephritis should be kept in mind.

Aged↗