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Biomedical subjects

M Kato

Publications and source records attributed to M Kato.

At least 37 records · Page 2Linked to original sources

Nested polymerase chain reaction for detection of the avian leukosis virus causing so-called fowl glioma.

The complete nucleotide sequence of the avian leukosis virus causing so-called fowl glioma has been previously determined. Primers were designed for detection of the fowl glioma-causal virus (FGV) based on the 3' untranslated region of the viral genome. The provirus and viral RNA of FGV were specifically detected in various organs and tissues, including feather pulp, from experimentally infected birds using nested polymerase chain reaction (PCR) and reverse transcription nested PCR. The prevalence of FGV was evaluated in 131 Japanese fowls of a zoological garden in Japan based on the detection of the FGV genome in feather pulp using PCR and the detection of viral antigen in faeces by enzyme-linked immunosorbent assay. FGV proviral DNA was detected in feather pulp of 52 birds (39.7%) by nested PCR. Later, nine dead birds from among the 52 were histologically diagnosed as having fowl glioma and found to have the proviral DNA in the affected brain. These results demonstrated that the PCR-based detection of FGV in feather pulp is useful for epidemiological studies on fowl glioma.

Animals↗

5-aminolaevulinic acid photodynamic therapy in a transgenic mouse model of skin melanoma.

Photodynamic therapy (PDT) is widely used to treat preneoplastic skin lesions and non-melanoma skin tumours. Studies analyzing the effects of PDT on malignant melanoma have yielded conflicting results. On the one hand, melanoma cell lines in culture as well as cell lines transplanted into experimental animals were sensitive to PDT. On the other hand, spontaneous melanomas of human patients responded poorly to most PDT regimens tested so far. Here, we analyzed effects of 5-aminolaevulinic acid (5-ALA)-based PDT on melanoma cell lines and on experimental melanomas. To mimic the clinical situation as closely as possible, metallothionein-I/ret (MT-ret) mice, a transgenic model of skin melanoma development, were used. Optimal doses of 5-ALA as well as energy doses and power densities were determined in vitro using a cell line (Mel25) established by us from a melanoma of an MT-ret transgenic mouse as well as commercially available human and mouse melanoma cell lines. Treatment with light irradiation alone had no effect. In combination with 5-ALA, however, this illumination readily induced the death of all mouse and human melanoma cell lines examined. Still, 5-ALA PDT caused only minor focal regressive changes including haemorrhages and fibrosis of MT-ret melanomas in vivo and did not significantly delay tumour growth. These results show that, even though MT-ret melanoma cells are vulnerable to 5-ALA PDT in vitro, malignant MT-ret melanomas in vivo are quite resistant to this type of therapy at doses which are highly effective in vitro.

Aminolevulinic Acid↗

Randomized, double-blind, placebo-controlled crossover trial of famotidine in patients with functional dyspepsia.

BACKGROUND: Histamine 2-receptor antagonists were used as a first therapy against functional dyspepsia. However, few clinical studies with famotidine for functional dyspepsia have been reported. AIM: To evaluate the effectiveness of famotidine for functional dyspepsia patients. METHODS: A multicentre, randomized, double-blind, placebo-controlled crossover trail was conducted. Patients diagnosed with functional dyspepsia by the Roma II criteria were included. Subjects were randomized into two groups, and received either famotidine or placebo as the first 4 weeks medication. After a 1-week washout period, they were switched to the other regimen for another 4 weeks. Evaluation was made prior to the start of study, upon completion of the first drug cycle, and the second drug cycle, by Gastrointestinal Symptoms Rating Scale for the seriousness of abdominal symptoms, and by Short Form-36 for the level of quality of life. RESULTS: Nineteen of 21 enrolled patients successfully completed this study. Significant improvement in Gastrointestinal Symptoms Rating Scale scores was observed in abdominal pain (P = 0.007), indigestion and reflux syndrome after famotidine treatment. Also quality of life scores showed significant improvement in body pain, vitality and general health perceptions after famotidine treatment. There was no improvement of symptoms and quality of life scores after administration of placebo. CONCLUSIONS: Famotidine was effective for improving symptoms and quality of life in functional dyspepsia patients.

Adult↗

Transgenic over-expression of macrophage migration inhibitory factor renders mice markedly more susceptible to experimental colitis.

Enhanced production of macrophage migration inhibitory factor (MIF) is recognized in patients with inflammatory bowel disease (IBD) and mice with experimental colitis; however, the precise molecular function of MIF in colitis is not fully understood. To further investigate this matter, we examined the pathological features of MIF transgenic mice with dextran sulphate sodium (DSS)-induced colitis. We generated transgenic mice carrying a murine MIF cDNA driven by a cytomegalovirus enhancer and a beta-actin/beta-globin promoter. Mice were orally administered 1-4% DSS in drinking water for 7 days. Clinical disease activity, survival and histological features were evaluated. The level of myeloperoxidase (MPO) activity in the colon tissue was measured to assess neutrophil infiltration. The level of corticosterone in the serum was measured by enzyme linked-immunosorbent assay (ELISA). MIF mRNA and protein were markedly up-regulated in the colon and serum obtained from MIF transgenic mice. The severity of the colitis induced by 1% DSS treatment was markedly higher in MIF transgenic mice than in wild-type mice. We also found that MPO activity was significantly higher in MIF transgenic mice than wild-type mice in response to DSS stimulation. Interestingly, the corticosterone level remained unchanged in MIF transgenic mice. MIF enhances DSS-induced colitis, in part via neutrophil accumulation and inhibition of glucocorticoid bioactivity.

Animals↗

Eleven-year clinical outcome of schizophrenia in Bali.

OBJECTIVE: To contrast the short-term and long-term outcome of schizophrenia in Bali. METHOD: The clinical outcomes of 46 schizophrenic patients (DSM-IV-TR) consecutively admitted to Bangli Mental Hospital were evaluated by Positive and Negative Syndrome Scale (PANSS) and Eguma's Social Adjustment Scale (ESAS) at a 11-year follow-up, which was subsequent to a 5-year follow-up. RESULTS: Neither the PANSS score nor the ESAS score were significantly different, and there was a significant correlation between the two follow-up data. Subjects categorized into either the best or worst outcome group at the 5-year follow-up tended to be classified into the same category at the 11-year follow-up more often than those who were categorized into the medium outcome groups at the 5-year follow-up. CONCLUSION: The 5-year outcome of schizophrenia strongly predicted the 11-year outcome, especially for subjects who had gone into either a remissive or severe deterioration state within 5 years.

Adult↗

Myocardial performance index for assessment of left ventricular outcome in successfully recanalised anterior myocardial infarction.

OBJECTIVE: To investigate whether the myocardial performance index (MPI) can predict left ventricular functional outcome in patients with early recanalisation after anterior acute myocardial infarction (MI) and to determine when the index should be measured. DESIGN: MPI was measured serially by two dimensional Doppler echocardiography after successful percutaneous coronary intervention (PCI). Left ventricular function was evaluated by echocardiography and left ventriculography. To assess coronary microvascular damage, the coronary flow velocity pattern was measured immediately after PCI with a Doppler guidewire. SETTING: Hiroshima City Asa Hospital. PATIENTS: 32 consecutive patients with their first anterior acute MI who had complete occlusion of left anterior descending coronary artery. INTERVENTIONS: Successful PCI within six hours of symptom onset. MAIN OUTCOME MEASURES: Left ventricular anterior wall motion score index (A-WMSI), left ventricular end diastolic pressure (LVEDP), left ventricular ejection fraction (LVEF), and left ventricular end diastolic volume (LVEDV). RESULTS: There was a significant negative correlation between MPI on day 2 and the coronary diastolic deceleration time (r = -0.66, p < 0.002), as well as a significant positive correlation with the coronary diastolic deceleration rate (r = 0.74, p < 0.0001). MPI on day 2 was significantly correlated with the short and long term changes of A-WMSI and with the short term changes of LVEDP. Furthermore, MPI on day 2 was significantly correlated with the short and long term changes of LVEF (r = -0.52, p < 0.003, and r = -0.64, p < 0.0008, respectively) and of LVEDV (r = 0.51, p < 0.003, and r = 0.41, p < 0.05, respectively). CONCLUSIONS: Doppler derived MPI on day 2, representative of the early coronary microvascular state, can predict the left ventricular functional outcome after early successful recanalisation of a patient's first anterior acute MI.

Aged↗

Toxoplasma gondii antigens GRA1 (p24) and SAG1 (p30): a comparison of their stimulatory influence on T-cell activation and cytokine expression in in vitro cultures.

The influence of recombinant cell surface SAG1 (rp30) and secretory GRA1 (rp24) antigens (Ag) on T-cell activation and cytokine induction in vitro was compared. T-cell activity and the level of IFN-gamma, IL-10 and IL-12 expression in rp30-immunized T cells were considerably increased in the presence of rp30 Ags. IgG2a and IgG1 antibodies (Ab) were detected in sera of rp24- and rp30-immunized mice, with the secretory rp24 Ag having induced significantly higher titer of IgG1 Ab. In vitro, the greater antigenicity of surface rp30 Ag was notable based on the level of T-cell activation, and cytokine synthesis suggestive of the participation of Th1 cells. Although, IFN-gamma expression by rp24 Ag was lower compared to rp30 Ag, the synthesis of both IgG2a and IgG1 Abs reflects the protective nature of rp24 Ag. We have generated two recombinant Toxoplasma gondii Ags that demonstrated differences in antigenicity in vitro. It would be interesting to evaluate the mechanism(s) of immunity induced by SAG1 (p30) and GRA1 (p24) Ags against infection with T. gondii in vivo.

Adenosine Triphosphate↗

Treatment of a Gilbert's syndrome patient with irinotecan, leucovorin and 5-fluorouracil.

The patient was an elderly male who had radical surgery for sigmoid cancer in 2001. Owing to metastasis of his cancer to the left supraclavicular lymph nodes in 2002, the patient was admitted to our hospital for systemic chemotherapy. We started treatment with irinotecan, leucovorin, 5-fluorouracil (IFL). After administering 100 mg/m2 of irinotecan, 250 mg/m2 leucovorin and 600 mg/m2 5-fluorouracil to the patient on day 1, grade 3 leukopenia developed rapidly and grade 4 thrombocytopenia was observed on day 5. We excluded irinotecan from the medication and continued the administration of 5-fluorouracil and leucovorin, but his tumors had not been reduced sufficiently. Based on some examination results, we assumed that the patient had Gilbert's syndrome and that the severe side effects that occurred were due to prolongation of SN38 metabolism. We again administered irinotecan but at reduced dose (25 mg/m2). Four courses of this modified IFL were administered safely and the response was favorable.

Aged↗

Toxicity and roles of reactive oxygen species.

The history of studies in biology regarding reactive oxygen species (ROS) is approximately 40 years. During the initial 30 years, it appeared that these studies were mainly focused on the toxicity or microbicidal-related agents of ROS. However, recent studies have identified another action regarding oxidative signaling, other than toxicity of ROS. Basically, it is suggested that ROS are reactive, and degenerate to biomacromolecules such as DNA and proteins, leading to deterioration of cellular functions as an oxidative stress. On the other hand, recent studies have shown that ROS act as oxidative signaling in cells, resulting in various gene expressions. For example, NADPH oxidase, a major source of superoxide radicals (O(2)(-)), expresses in various tissues such as leukocytes and cardiovascular systems, and ROS derived from the enzyme play important roles in cell proliferation, differentiation, and cell death. In this review, we have focused on and described the basic properties, toxicity, and roles of ROS.

Animals↗

Oxygen radicals in inflammation and allergy related to viral infections.

Oxygen radicals including superoxide anion (O(2)(-)) and nitric oxide (NO) are involved in a variety of inflammatory diseases induced by viral infection. In this review, we focus on the role of oxygen radicals in allergic inflammation such as bronchial asthma induced by viral infection--specifically, with respiratory syncytial virus (RSV). This infection in early childhood is a risk factor for development of wheezing, significant decreases in pulmonary function, and increases in airway reactivity. RSV infection also exacerbates recurrent wheezing attacks in patients with established asthma. Recently, we have demonstrated that RSV enhanced superoxide production by human eosinophils stimulated with a lipid mediator such as platelet-activating factor. This response depends on a beta2 integrin, alphaMbeta2, which is critical for eosinophil effector functions. Our results suggest that eosinophils and their products promote RSV-induced airway inflammation in asthma. Close delineation of the mechanism by which RSV enhances eosinophilic inflammation in asthma should yield clues to more effective therapy.

Animals↗

[Pulmonary hemangiopericytoma preoperatively diagnosed as mediastinal tumor; report of a case].

An asymptomatic 67-year-old female was admitted because of an abnormal shadow on chest X-ray. Computed tomography (CT) revealed that a well-marginated round mass with low density, about 4 cm in diameter, was located in the right hilum. The border was enhanced at contrast material-enhanced CT. Magnetic resonance imaging (MRI) [T2-weighted] showed the lesion as a high intensity tumor. Because of the extra-pleural sign on CT and normal results of broncho-fiberscopic (BFS) examination, mediastinal tumor was suspected. We performed thoracoscopic surgery and revealed that the tumor was in lung, not in mediastinum. Biopsy of the easy-bleeding tumor was performed. The histopathological diagnosis was hemangiopericytoma. There was no remarkable change for 1 years. Hemangiopericytomas should be considered in the differential diagnosis of well-marginated masses. Thoracoscopic surgery is the useful methods to diagnose the hemangiopericytoma.

Aged↗

[Traumatic rupture of the ascending aorta].

A 42-year-old male was diagnosed as having a traumatic rupture of the ascending aorta 24 hours after traffic accident. On admission, the patient was in a state of shock, but he was successfully treated by emergency surgery. Traumatic rupture of the ascending aorta is a serious condition and the mortality may be very high. Although physicians rarely encounter patients with this condition, it is relatively common among autopsy cases with multiple trauma. Urgent diagnosis and treatment are mandatory.

Adult↗

[Usefulness of the eradication of Helicobacter pylori for the patient with idiopathic thrombocytopenic purpura and lung cancer: report of a case].

A 61-year-old female was admitted because of an abnormal lung shadow on chest X-ray. She had suffered from idiopathic thrombocytopenic purpura (ITP) for more than 7 years. Computed tomography (CT) revealed that an irregular shadow, about 2 cm in diameter, was located in the upper lobe of the right lung. After intravenous immunogrobulin injections for 5 days, a hematology test indicated increased platelet counts and we performed thoracoscopic surgery successfully without blood transfusions. However, 4 months after surgery, a hematology test indicated decreased platelet counts again. Thirteen months after the operation, gastrointestinal fiberscopic examination showed Helicobacter pylori infection. After the urea breath test, eradication therapy let to a recovery in platelet counts.

Adenocarcinoma↗

[Aortic root remodeling and coronary artery bypass grafting for acute type A aortic dissection involving the left main coronary artery; report of a case].

A 56-year-old male was admitted for sudden chest pain followed by loss of consciousness and paraplegia. The electrocardiogram (ECG) revealed ST-elevation in leads II, III, and aVF and ST-depression in leads V3 to V6. The ultrasonic cardiography (UCG) demonstrated an intimal flap in the ascending aorta, grade III aortic regurgitation (AR), and akinesis of the posterior wall of the left ventricle. Transesophageal echocardiography directly showed dissection of the left main coronary artery. Emergency coronary artery bypass grafting (CABG) to the left anterior descending artery (LAD), obtuse marginal artery (OM) and posterolateral artery (PL) was performed using the saphenous vein. In addition, valve-sparing aortic root remodeling was performed in conjunction with replacement of the ascending aorta. The left coronary orifice was repaired and reattached to the prosthetic graft. The patient was weaned from cardiopulmonary bypass without catecholamine support. He was discharged from the hospital on foot after rehabilitation of the paraplegia. AR remains mild by UCG 3 years after surgery.

Acute Disease↗

[Cardiac papillary fibroelastomas: report of 2 cases].

We report 2 cases of cardiac papillary fibroelastomas in adults. Case 1: A 61-year-old man was admitted because echocardiography showed a 1 cm pedunculated papillary tumor in the left atrium. In an operation, it was located in the left atrium near the mitral valve and was resected along with a 5 mm margin of endocardium. Case 2: A 60-year-old woman had a 1 cm mobile tumor in the right ventricle near the tricuspid valve located by echocardiography in a preoperative examination of a ventricular septal defect. In an operation, a pedunculated tumor located in the right ventricle was resected. In these 2 cases, histopathology showed the tumor to be a papillary fibroelastoma. Almost all cardiac papillary fibroelastoma are closely related to the cardiac valve, but in these cases, the tumors were located in the left atrium, and the right ventricle, respectively, which is quite rare.

Cardiac Surgical Procedures↗