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Biomedical subjects

Y Hamamoto

Publications and source records attributed to Y Hamamoto.

At least 55 records · Page 3Linked to original sources
PubMed1998

[A case of polymyositis with anti-Jo-1 antibody preceded by BOOP].

A 56-year-old man experienced dyspnea since August 1995 and the chest X-ray film showed abnormal shadow. The diagnosis of bronchiolitis obliterans organizing pneumonia (BOOP) was established based on the histological findings of transbronchial lung biopsy. The patient was treated with prednisolone and symptoms improved. Myalgia and muscle weakness developed associated with relapse of BOOP after withdrawal of prednisolone. Patient was admitted to our department on December 1995 for further examination. An increased level of serum CPK, histological findings of muscle biopsy consistent with myositis, and positive anti-Jo-1 antibody were identified. Those findings supported a diagnosis of polymyositis (PM), and BOOP was considered as a pulmonary complication of PM. Myositis and pulmonary lesion improved after second course of steroid therapy and patient was discharged on May 1996. Both chronic pulmonary fibrosis and acute progressive interstital pneumonia are well known as pulmonary lesion associated with PM. The former is frequently recognized in cases of PM with anti-Jo-1 antibody and the latter is often observed in cases without autoantibodies. The association of PM and BOOP, however, has rarely been reported. The findings that BOOP frequently preceded PM and anti-Jo-1 antibody was positive in half of the cases were observed in the literature.

Antibodies, Antinuclear↗
PubMed1997

Association of apolipoprotein allele epsilon 2 with psoriasis vulgaris in Japanese population.

We studied phenotypic variations of apolipoprotein E (apoE) and the corresponding allele frequencies in 100 Japanese patients with psoriasis vulgaris (PV). The phenotypes of apoE were examined using analytical isoelectric focusing followed by immunoblotting with goat anti-apoE antibody and alkaline phosphatase-conjugated rabbit antigoat IgG. The phenotypic frequency of apoE3/2 in PV was significantly higher than in healthy controls, and this elevation was associated with an increased frequency of the epsilon 2 allele. Therefore, it is suggested that the apoE molecule plays an important role in the development of PV.

Adolescent↗
PubMed1997

Establishment and characterization of a novel human cell line exhibiting both immunophenotypic markers of monocyte/macrophage and natural killer cell lineages from peripheral blood of a patient with atopic dermatitis.

Large amounts of homogeneous cells are not always available for in vitro studies of inflammatory skin disorders. Here we demonstrate that a novel cell line, termed YAA, has been established from peripheral blood mononuclear cells, which were separated by the Ficoll method, of a patient with atopic dermatitis. YAA cells were grown in suspension culture. The cytochemical staining showed a positive reaction for alpha-naphthyl butyrate esterase, which was completely inhibited by sodium fluoride, but a negative result for periodic acid-Schiff, peroxidase and alkaline phosphatase. A large population of YAA cells exhibited phenotype of CD33 and CD56 but neither of CD2 nor CD3. The phorbol ester-stimulated YAA cells produced a considerable amount of tumor necrosis factor-alpha. These findings suggest that YAA might be a monocytoid line with an additional phenotype specific for natural killer cells.

Adult↗
PubMed1996

Establishment and characterization of a novel human promonocytic cell line from peripheral blood of a patient with psoriasis.

Human monocyte/macrophage lineages have unique phagocytic and immune-regulatory functions. We established a promonocytic cell line from the peripheral blood of a patient with psoriasis vulgaris. The newly established cells, termed YAP cells, grew in a suspension culture. In Wright-Giemsa-stained preparations, YAP cells were round or polygonal in shape. Transmission electron microscopy showed that the cells had clear nuclei with well-defined nucleoli. There were frequent mitochondria, a relatively abundant endoplasmic reticulum profile, free ribosomes and an occasional Golgi apparatus. Cytochemical studies showed a positive reaction for alpha-naphthyl butyrate esterase, which was completely inhibited by sodium fluoride, a diffuse positive reaction for periodic acid-Schiff, and a negative result for alkaline phosphatase and peroxidase. A large population of YAP cells reacted with the CD4, CD11b, CD25 and CD33 surface markers, but not with CD2, CD3, CD8 or CD19. We also found that YAP cells produced considerable amounts of TNF alpha, which was detected in the culture supernatant when the cells were treated with 1 ng/ml 12-O-tetradecanoylphorbol-13-acetate (TPA). Chromosome analyses showed that YAP cells contained a variety of marker chromosomes. It should be stressed that YAP cells were derived from a patient with a non-neoplastic disorder, whereas most monocytic cell lines previously reported are of malignant origin. This newly established cell line might be valuable for studying the pathogenesis of psoriasis, especially the role of monocytes/macrophages in the aetiology of the disease.

Adult↗
PubMed1996

Production of amelogenin by enamel epithelium of Hertwig's root sheath.

OBJECTIVE: To study the multiple potentials of differentiating odontogenic epithelial cells. STUDY DESIGN: Bilateral first and second maxillary molars of 30 immature rats were perforated into the pulp chambers with a round bur. The pulps were observed histologically and immunohistochemically for amelogenin 3, 7, and 14 days after the perforation. RESULTS: On day 7, the enamel epithelium of Hertwig's root sheath migrated and formed oval-shaped epithelial islands that resembled epithelial rests of Malassez. On day 14, the islands consisted of epithelial cells with large nuclei and cytoplasm partially surrounded by a subsequently formed osteodentin and cementum. Immunoreactivity for amelogenin was observed in the large epithelial cells and in the area between the cells as well as the calcified tissues. Some of the enamel epithelium resembling columnar ameloblasts of the enamel organ were also positive for amelogenin. CONCLUSIONS: The enamel epithelium of Hertwig's root sheath appeared to differentiate into ameloblasts and produce amelogenin.

Ameloblasts↗
PubMed1996

Putative linkage between HLA class I polymorphism and the susceptibility to malignant melanoma.

Human leukocyte antigen (HLA) frequencies in 67 melanoma patients were compared to 120 controls in Japan. The frequency of HLA-B13 was increased in melanoma patients compared to controls and was particularly common in nodular melanoma HLA-B61 was decreased in melanoma patients. Almost 50% of acral lentiginous melanoma patients expressed HLA-B51 compared to 0% of nodular melanomas.

Asian People↗
PubMed1996

Immune response to Streptococcus pyogenes and the susceptibility to psoriasis.

Monoclonal antibodies directed against type 12 Group A streptococcal cell wall antigens cross-react with nuclei and cytoplasm of cells from skin and synovium from controls, uninvolved skin of psoriatics and psoriatic plaques. Patients with psoriasis had high serum titres of antibody against the M12 (C-region) streptococcal antigen compared to controls. An abnormal immune response directed against a "self' antigen after initiation by Group A streptococcal infection may play an important role in the exacerbation or development of psoriasis.

Antibodies, Monoclonal↗
PubMed1996

[Two cases of recurrent, massive hemoptysis with contralateral, concurrent hemoptysis].

Bilateral, concurrent massive hemoptysis with respiratory failure is rare and difficult to manage. We encountered two patients with this condition. One was a 51-year-old woman and one was a 63-year-old woman. Both had inactive pulmonary tuberculosis and episodes of hemoptysis. Home oxygen therapy was prescribed to the former patient and bronchial artery embolization was done in the latter. The sites of initial bleeding were in the left basal segment and in the lingular segment. Bleeding was well controlled by endobronchial tamponade with a Fogarty balloon catheter in the left main bronchus, contralateral intubation, and systemic artery embolization. Use of water instead of air in the balloon was more effective in over the long term. Concurrent bleeding from the contralateral upper lobe bronchus was controlled by compression with a tracheal tube cuff at the bronchial orifice. Afterward, an infiltrative shadow was seen on the chest X-ray film and hemoptysis occurred in case 2 occurred in case 2. Treatment with erythromycin and antituberculosis drugs brought about improvement of chest X-ray findings and disappearance of the hemoptysis.

Antitubercular Agents↗
PubMed1996

Anti-tumor effects of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) in seborrheic keratosis.

1,25-dihydroxyvitamin D3 (1,25(OH)2D3) is a drug with potent antiproliferative action on keratinocytes that have nuclear receptors for 1,25(OH)2D3. We investigated the effects of 1,25(OH)2D3 on widespread seborrheic keratoses in 51 patients with these tumors. The data indicated that resolution of these tumors was dependent on both tumor size and dose of 1,25(OH)2D3. Among 15 patients treated with a high dose (0.5 microgram/d) of oral 1,25(OH)2D3, the lesions of widespread seborrheic keratoses changed from brown-black papules to brownish papules with erythema and/or crust as early as 2 wk after the start of treatment. The tumors finally developed into an atrophic scar or brownish pigmented macule. Histologically, vacuolation of the spinous cells, vesicle formation, and liquefaction degeneration of the basaloid cells were observed. Numerous lymphocytes had infiltrated in the papillary dermis. Among 36 patients treated with a low dose (0.25 microgram/d) of 1,25(OH)2D3, brownish papules became pale to normal in color and reduced in size, without erythematous change. Histologically, acanthosis of the epidermis was reduced, but degenerative change of the tumor cells was not observed. These data suggest that oral therapy of 1,25(OH)2D3 is an acceptable method well suited to the removal of seborrheic keratoses, especially those that are predominantly small tumors.

Adult↗
PubMed1995

Histological, histocytochemical and ultrastructural study on the effects of surface charge on bone formation in the rabbit mandible.

The osteogenic potential of different surface charges was studied by implanting uncharged, negatively changed and positively charged Sephadex beads subperiosteally on the buccal aspect of the mandible. The implant sites were examined 1, 2, and 4 weeks later. New bone formation was observed around the positively charged beads at 2 weeks. An amorphous collagen-free layer seen around the beads consisted of anionic substances and contained needle-like crystals. Tartrate-resistant acid phosphatase-positive, multinucleated giant cells, which had typical fine structural characteristics of osteoclast-like ruffled borders and a clear zone, were observed on the surface of positively charged beads, with osteoblastic cells juxtaposed to them. Bone formation was still going on at 4 weeks in this group. Around the uncharged or negatively charged beads, new bone formation and osteoclast-like cells were not observed at any time. The findings suggest that the surface charge of implant materials has a definite influence on the differentiation of osteoclastic cells and subsequent occurrence of osteoblastic cells leading to formation of bone.

Acid Phosphatase↗
PubMed1995

Necrotizing fasciitis due to Pasteurella multocida infection.

Necrotizing fasciitis is a potentially fatal clinical disease caused by infection with various bacteria in addition to streptococci, which are common causative agents. We report on a rare case of this disease in association with Pasteurella multocida infection. A 58-year-old man had systemic features of shock after a 15-hour history of a painful swelling on the right lower leg. The swelling led to skin blistering and necrosis from which P. multocida was isolated. Those lesions progressed rapidly. The patient also had a history of chronic liver injury as described in previous reports.

Blister↗
PubMed1994

[Wegener's granulomatosis--report of four cases including two in patients who died of myocardial infarction].

The prognosis for Wegener's granulomatosis (W-G) is good if it is diagnosed early and a combination of corticosteroids and cytotoxic drugs is given. During the past fourteen years, we were encountered four cases of W-G, three were systemic and one was limited. Of the three patients, with systemic disease, two died of myocardial infarction caused by a delay in diagnosis and one died of fulminant renal and respiratory failure. Only the one patient with a limited form of the disease survived for more than 5 years. We emphasize the importance of early diagnosis with consideration of the systemic features of W-G.

Acute Kidney Injury↗
PubMed1994

[Clinical studies on nine cases with miliary tuberculosis: serum level of tumor markers and bronchoscopy in differential diagnosis].

We analyzed retrospectively the clinical data of 9 patients with miliary tuberculosis who had been treated in Kyoto City Hospital during the past 12 years. Majority of our patients were female (7 of 9) and were of elder age-groups (mean age: 68.5 years, range: 56-85 years). The most common symptoms at the first visit were fever, fatigue and loss of appetite, but respiratory symptoms were rather rare and moderate. Some cases showed normal chest radiograms at the onset, but during the course of the disease miliary shadows were noticed in all cases. Tuberculin test and smear examination of sputum were not diagnostic. In 4 cases, fiberoptic bronchoscopy had been performed together with bronchoalveolar lavage (BAL), bronchial washing and transbronchial lung biopsy (TBLB). Smear examination BAL-fluid or bronchial washing for acid-fast bacilli was positive in all 4 cases tested. In 7 cases, serum level of tumor markers (CEA, TPA, SLX, NSE, SCC, CA19-9, CA125, DU-PAN 2 and Elastase I) had been measured under the suspicion of malignant diseases. CEA had elevated in 6 cases, NSE in 2 cases, SLX, TPA, CA19-9, CA125 and DU-PAN 2 in 1 case each, and, as a whole, at least one tumor marker had elevated in 6 of 7 cases tested. Though the degree of such elevation of tumor markers had not been so remarkable except for CA125 in a patient who had been complicated with tuberculous peritonitis, but from these results malignancy had not been' able to rule out.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

[An autopsy case of adenosquamous cell carcinoma of the extrahepatic bile duct with endobronchial mass obstructing the left main bronchus and masquerading as asthma].

A 65-year-old male was admitted with diagnosis of bronchial asthma. On admission, he was orthopneic, cyanotic and distressed. Marked hypoxemia with PaO2 of 31.1 mmHg was noted, but no obvious localized airway obstruction on plain chest X-ray film could be detected. These was minimal response to intensive treatment with steroid in addition to various bronchodilators on the presumed diagnosis of bronchial asthma. Two weeks later, chest X-ray disclosed complete atelectasis of the left lung. Stenosis of the left main bronchus with enlarged mediastinal lymph nodes on chest CT was suggested. Endoscopic examination disclosed complete obstruction of the left main bronchus just beyond the carina and polypoid tumors in the right main bronchus and basal segment bronchus. The biopsy specimens revealed squamous cell carcinoma. Chemotherapy with CDDP and VDS resulted in disappearance of atelectasis after one week and marked relief of respiratory distress. Four months later, at the completion of irradiation therapy, an abdominal tumor associated with pain appeared and bone scintigram showed multiple bone metastases. After four times chemotherapy including CDDP, hypercalcemia and renal hypofunction developed, and the patient died. Autopsy disclosed a tumor in the extrahepatic bile duct, cystic lesions of the pancreas and swelling of subcarinal lymph nodes, but no tumorous lesion in the lung and endobronchial tissue. Histological examination of the extrahepatic bile duct tumor revealed adenosquamous cell carcinoma, with predominantly squamous cell carcinoma. Other metastatic lesions consisted of squamous cell carcinoma. These findings are compatible with pulmonary metastases of adenosquamous cell carcinoma of the extrahepatic bile duct.

Aged↗
PubMed1994

[Angiographical frequency of unruptured incidental intracranial aneurysms].

We reviewed cerebral angiograms studied between May 1985 and December 1992 focusing on unruptured incidental intracranial aneurysms. In a total of 605 cases of cerebral angiograms except for patients with SAH, 43 patients (7.1%) were found to have unruptured aneurysms. In the 72 patients with headache, 11 patients (15.3%) were found to have unruptured aneurysms. This high frequency of unruptured aneurysms in headache patients is significant as a factor showing that headache may be due to unruptured aneurysms. The result of this observation is that as a screening study for headache patients, cerebral angiography may be required in spite of the invasive and high-risk method. But we think that MR angiography is, at present, a useful screening study only for detecting cerebral aneurysms with a diameter of over 5mm, and which are considered to need an operation.

Age Factors↗
PubMed1993

Inhibitory effect of azelastine, a potent antiallergic agent, on release of tumor necrosis factor-alpha from activated human peripheral blood mononuclear cells and U937 cells.

It is generally accepted that tumor necrosis factor-alpha (TNF-alpha) is a multifunctional cytokine which is involved in the regulation of inflammation as well as immunity. In the present study, we investigated whether azelastine, a potent antiallergic agent, affects release of TNF-alpha from peripheral blood mononuclear cells (PBMC) and U937 cell line in vitro. When human PBMC and U937 cells were stimulated by phytohemagglutinin (PHA) and 12-0-tetradecanoyl-phorbol-13-acetate (TPA), respectively, the cells released significant amounts of TNF-alpha as determined by TNF-alpha-specific enzyme immunoassay. TNF-alpha levels in the culture supernatant of PHA-stimulated human PBMC and TPA-activated U937 cells decreased in a dose-dependent manner when these cells were cultured in the presence of azelastine. This inhibitory effect of azelastine was obtained at concentrations where the drug produced no toxicity. Moreover, azelastine also inhibited release of TNF-alpha from U937 cells which were already activated by TPA. These results suggest that the inhibitory effect of azelastine on TNF-alpha release plays an important role in its antiallergic action in addition to inhibition and/or antagonism of histamine and leukotrienes, which has been previously reported.

Depression, Chemical↗