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T Yazawa

Publications and source records attributed to T Yazawa.

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

Angiocytotoxic therapy in human non-small cell lung cancer cell lines--advantage of combined effects of TNP-470 and SN-38.

The combined effects of TNP-470, a promising antiangiogenic agent, and SN-38, a camptothecin derivative, were evaluated in four human cultured cell lines derived from non-small cell lung cancer (NSCLC). Cytotoxicity experiments were determined by using a tetrazolium salt (MTT) assay. The inhibitory effects of TNP-470 on cell proliferation were dose related and the 50% inhibitory concentrations on these cell lines were 47.3-139.8 microM. Evaluation of drug interactions with isobologram and the combination index values showed that sequential exposure to SN-38 followed by TNP-470 produced synergistic effects in the four cell lines tested. Our findings suggest that such an angiocytotoxic chemotherapy might be promising for the treatment of NSCLC.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

A pharmacological and HPLC analysis of the excitatory transmitter of the cardiac ganglion in the heart of the isopod crustacean Bathynomus doederleini.

In crustacean neurogenic hearts, the myocardium contracts under the tight control of rhythmically active neurons of the cardiac ganglion located inside the heart. We demonstrated that the myocardium of Bathynomus doederleini was sensitive to glutamate, quisqualate, and kainate, and that the tension of myocardial cells developed in a dose-dependent manner. The threshold concentrations were 10(-5) M for quisqualate, 10(-4) M for glutamate, and 3 x 10(-4) M for kainate. Concanavalin A, known to prevent desensitization of glutamate receptors at crustacean neuromuscular junctions, augmented excitatory junctional potentials evoked by the cardiac ganglionic neurons in myocardial cells. Using a high performance liquid chromatography (HPLC), we analyzed glutamate in extracts of the cardiac ganglion and myocardium. We obtained values for glutamate concentrations, 8741.2 +/- 184.2 and 678.2 +/- 10.7 pmol/mg, respectively. Although we attempted to measure monoamines in the extracts by HPLC, these were not detected at measurable (more than 1 fmol per 10-microL sample) levels. In conclusion, myocardial cells in isopod crustaceans were suggested to receive glutamatergic motor innervation.

Animals↗
PubMed1998

[The coexistence of pulmonary tuberculosis and thymoma a case report].

A 33-year-old male was admitted with complaints of cough, dysphagia, and swelling of face and upper extremities. Chest X-ray and CT scan revealed a large mediastinal mass and infiltrates in the right upper lobe. Percutaneous biopsy proved the mediastinal tumor as thymoma with cellular atypia. After irradiation, the tumor was surgically removed. Caseous epitheloid granulomas were found in the dissected mediastinal lymph nodes. AFB (Acid fast bacillus) stain of the patient's gastric fluid was positive for Mycobacterium. The coexistence of these two diseases was incidental, however, this case suggested that clinicians should perform careful evaluation of lung parenchyma as well as mediastinum on chest X-ray to identify occult diseases including pulmonary tuberculosis in patients with mediastinal mass lesion.

Adult↗
PubMed1997

Urokinase-type plasminogen activator in carcinomatous pleural fluid.

Urokinase-type plasminogen activator (u-PA) is known to be secreted by malignant cells during proliferation and migration, and is associated with tumour cell invasion and metastasis. This study was undertaken to evaluate whether u-PA is significantly increased in carcinomatous pleural fluids compared to those due to other aetiologies, and to identify the cells in the pleural space that are involved in its accumulation. Using an enzyme-linked immunosorbent assay, we quantified u-PA in the pleural fluid specimens of 40 patients with carcinomatous pleuritis, 18 with tuberculosis, 18 with parapneumonic pleuritis and 11 with congestive heart failure (CHF). The level of u-PA was elevated in carcinomatous pleural fluid compared with the level in transudative pleural fluid from patients with CHF (p<0.0001). The levels of u-PA were not statistically different between patients with cancer and tuberculosis, or between patients with cancer and pneumonia. The levels of u-PA in patients who did not respond to chemical pleurodesis were significantly higher than those who had complete response (p=0.0001). In immunocytochemical and immunoblotting studies, cancer cells in pleural fluids as well as mesothelial cells contained u-PA. u-PA was detected in the culture supernatants of viable pleural cells in the majority of patients with carcinomatous pleuritis. Our results suggest that local release of urokinase-type plasminogen activator by viable cells, including cancer cells and mesothelial cells, may affect the levels of urokinase-type plasminogen activator in pleural fluids.

Adenocarcinoma↗
PubMed1996

Electrocardiographic abnormalities in patients receiving hemodialysis.

We assessed standard 12-lead and Holter electrocardiographic (ECG) abnormalities in maintenance hemodialysis (HD) patients. Of 221 outpatients receiving HD, 143 (65%) had ECG abnormalities. Rates were higher in male, elderly, hypertensive, and diabetic patients than in female, younger, normotensive, and nondiabetic patients. The prevalence of ECG changes correlated inversely with HD duration. Serial ECGs were compared in 87 patients whose average HD duration was 7.5 +/- 2.5 years. Thirty-four patients (39%) showed normal ECGs throughout, 27 (31%) relatively stable abnormalities, 22 (25%) worsening, and 4 (5%) reversion to normal. Age, hypertension, and diabetes are factors related to abnormal ECG findings. Among the 142 Holter recordings from 72 patients, 70 (97%) were basically in sinus rhythm, and 2 (3%) were in atrial fibrillation. The average frequency of supraventricular premature contractions (SVPCs) was 1597 +/- 9725 per 24 hours, and that of ventricular premature contractions (VPCs), 556 +/- 1415. VPCs were multifocal in 9%, in runs in 25%, and early in 1%. In 29 (40%) of recordings, VPCs appeared mainly during and for several hours after HD. ST-T changes were seen in 43 (60%). In 11, ST depression occurred during and a few hours after HD. Patients receiving HD showed diverse ECG abnormalities. Holter ECGs revealed a high incidence of arrhythmias and ST-T changes, which frequently appeared in relation to HD timing.

Adolescent↗
PubMed1996

[Diffuse malignant mesothelioma associated with asbestos pleurisy].

Asbestos pleurisy is relatively uncommon among patients who present with pleural fluid. Association of diffuse malignant mesothelioma with asbestos pleurisy has not been reported in Japan, although 10 cases have been reported in the world literature. We encountered a 51-year-old man in whom diffuse malignant mesothelioma developed during a 5-year course of asbestos pleurisy. Mesothelial cells in patients with asbestos pleurisy are likely to be exposed to asbestos for a long time, which may increase the risk that mesothelioma will develop.

Asbestos↗
PubMed1994

Infantile progressive spinal muscular atrophy with ophthalmoplegia and pyramidal symptoms.

Two siblings presented with identical features of progressive peripheral paralysis of the lower motor neuron type, pyramidal signs, cranial nerve palsy which included external ocular palsy and deafness, and internal ocular palsy; both died before 1 year of age. Pathologic examination of the central nervous system in both patients revealed degeneration and loss of spinal and cranial nerve motor nuclei, including the oculomotor nucleus. In addition, there was degeneration of the Edinger-Westphal nuclei and demyelination of the corticospinal tract under the midbrain. Although spinal cord lesions were indistinguishable from those of Werdnig-Hoffmann disease, the 2 patients are not considered to have Werdnig-Hoffmann disease from the clinicopathologic findings.

Brain↗
PubMed1994

Histopathology of canine hearts subjected to catheter ablation using radiofrequency energy.

To investigate the pathologic changes of the myocardium and the adverse effects of radiofrequency (RF) catheter ablation, we observed canine hearts that had been ablated by RF energy. Catheter ablation was administered to three sites of the hearts of 46 dogs: endomyocardium, coronary sinus, and atrioventricular junction. The dogs were sacrificed 0-12 weeks after ablation and the lesions were stained with hematoxylin-eosin and Azan stain. Each ablated lesion was well demarcated from the adjacent normal tissue. The margin between the ablated lesion and normal tissue became clearer with time. The lesions were hemispherical and measured about 2 to 10 mm in diameter and 1 to 6 mm in depth. Histologic examination in the acute phase demonstrated the presence of coagulation necrosis of the myocardium, interstitial hemorrhage and edema, followed by infiltration of inflammatory cells. Granulation tissue replaced the normal myocardium. In the chronic phase, the lesions became fibrotic and fatty. A mural thrombus was found in 30% of the cases of endomyocardial ablation and 50% of the right ventricular lesions were transmural. Ablated lesions in the coronary sinus extended to the left atrium and left ventricle. Obstruction of the coronary sinus was observed in 8% of the ablated dogs. Most of the lesions with complete atrioventricular block were ablated at the His penetrating region of the conduction system. Thus, since the ablated lesions were clearly delineated, catheter ablation using RF energy appears to eliminate only the target area.

Animals↗
PubMed1994

Successful pregnancy after curative therapy for advanced lung cancer.

We report a single case in which two successful pregnancies occurred in a young woman following curative management of an advanced adenocarcinoma of the lung with resectional surgery and high-dose postoperative radiotherapy. This is the first case of advanced lung cancer with a favorable outcome.

Adenocarcinoma, Papillary↗
PubMed1994

[Adult Wilms's tumor with histologically dissisimilar lung metastasis].

A 41-year-old man incidentally found to have a right renal and left large lung tumor in the course of screening for liver dysfunction was admitted to our hospital. Needle biopsy of each tumors revealed histologically renal cell carcinoma and pulmonary blastoma. The renal tumor grew rapidly and soon he died of DIC. Autopsy was performed and the final diagnosis was adult Wilms' tumor and its metastasis to the lung. Histological findings of each large tumors showed different histologic pattern. The renal tumor revealed diffuse nephroblastic subtype and the lung tumor showed epitherial type. This is a rare case of Wilms' tumor in terms of its adult onset and different histologic pattern between the primary tumor and its metastatic lesion.

Adult↗
PubMed1994

[Clinical diagnosis of early breast cancer].

During the recent 5 years between 1988 and 1992, 254 cases of breast cancer were experienced in the Tsukuba University Hospital. Of them, 80 cases were palpable cancers measuring less than 2cm and 37 cases were nonpalpable cancers. The total of early cancers was 117 cases, 43.3% of all cases. Noninvasive carcinoma without minimally invasive carcinomas were 35 cases, 13.2% (ductal ca: 27, lobularca: 2, Paget ca: 6). According to the palpability of tumour mass, the sensitivity and accuracy rate of palpable early masses are 56.6% and 88.4% by physical examination, 57.9% and 96.4% by mammography, 77.6% and 82.5% by echography respectively. Those of nonpalpable diseases are 29.0% and 88.8% by physical examination, 42.9% and 91.2% by mammography, and 32.1% and 76.8% by echography. The sensitivity of echography for palpable breast cancer is extremely high. On the other hand, mammography is the most effective for nonpalpable cancer. For the detection of noninvasive carcinoma, characteristics of nipple discharge, measurement of CEA in nipple discharge and erosion of the nipple are other important factors.

Adult↗
PubMed1993

Identification of defect in the genes for bilirubin UDP-glucuronosyl-transferase in a patient with Crigler-Najjar syndrome type II.

Crigler-Najjar syndrome (CN) type II is characterized by severe chronic nonhemolytic unconjugated hyperbilirubinemia due to reduced hepatic bilirubin UDP-glucuronosyl-transferase (UGT) activity. Two bilirubin UGT isozymes, UGT1A and UGT1D, have been identified. We analyzed the DNA sequence of the bilirubin UGT genes in a 5-year-old Japanese male patient with CN type II, who had consanguineous parents. Point mutations were found on exons 1 of the UGT1A and UGT1D genes. The abnormalities were single nucleotide substitutions of G by A and of T by C at base position 211 of UGT1A cDNA and at base position 395 of the UGT1D, respectively. We found another single nucleotide substitution of T by G on exon 5 common to both genes at base position 1456 of the UGT1A cDNA or 1459 of the UGT1D cDNA. These three mutations result in changes of glycine to arginine and of tyrosine to aspartic acid at amino acid positions 71 and 486 of the UGT1A protein, and of leucine to proline and of tyrosine to aspartic acid at amino acid positions 132 and 487 of the UGT1D protein, respectively. Our patient was homozygous for all defects and his parents and elder brother were heterozygous for all defective alleles. The findings suggest that the CN Type II is inherited as an autosomal recessive trait.

Adult↗
PubMed1993

Clear cell carcinoma of the lung: a case report and review of the literature.

Clear cell carcinoma of the lung is an extremely rare type of lung cancer with doubtful etiology. This present case showed that the tumor cells contained abundant cytoplasmic glycogen with a diffusely distributed pattern and intracellular glandular structure electron microscopically. Immunohistochemical study revealed that the tumor cells expressed not only epithelial marker including cytokeratin and epithelial membrane antigen, but also Ley, one of stage-specific embryonic carbohydrate antigens. The diagnosis of pulmonary clear cell carcinoma should be done carefully, because benign clear cell tumor and secondary renal cell carcinoma show similarities in a histologic appearance but not in their management and prognosis.

Adenocarcinoma, Clear Cell↗
PubMed1993

Urinary trehalase activity in chronic glomerulonephritis.

To determine the diagnostic role of urinary trehalase in chronic glomerular disease, urinary trehalase activity and other urinary markers such as N-acetyl-beta-D-glucosaminidase (NAG), alanine aminopeptidase (AAP), alkaline phosphatase (ALP), gamma-glutamyltranspeptidase (gamma-GTP), lactate dehydrogenase (LDH), lysozyme and beta 2-microglobulin (BMG) were measured in patients with chronic glomerulonephritis, nephrotic syndrome and chronic renal failure. Urinary trehalase activity was significantly increased in chronic glomerular disease, especially nephrotic syndrome, as compared with that in the healthy subjects. The highest incidence of elevated excretion was observed for trehalase with 52% in chronic glomerular disease, followed by NAG. Urinary trehalase activities in the patients were significantly correlated with the urinary levels of protein, NAG and AAP and total score of tubular damage, but not correlated with urinary levels of BMG or lysozyme. In patients with chronic glomerulonephritis and nephrotic syndrome, there was no significant difference in urinary trehalase activities between with and without hematuria. These results indicate that in some patients with chronic glomerular disease, there is tubular involvement as substantiated by elevation of the other urinary enzymes and BMG. Urinary trehalase is elevated more often in these types of disease than other markers of tubular damage.

Acetylglucosaminidase↗
PubMed1992

Diabetes mellitus in cattle infected with bovine viral diarrhea mucosal disease virus.

Four Japanese black cattle and four Holstein-Friesian cows were diagnosed with diabetes mellitus. Based on intravenous glucose tolerance tests, all these animals were believed to be insulin-dependent diabetics. Moreover, bovine viral diarrhea-mucosal disease (BVD-MD) virus was isolated and mucosal lesions and diarrhea were recognized in all cases. There was no genetic relation among the affected cattle. The breeding places of these cattle were different to each other. Therefore, it is suggested that BVD-MD virus induced the diabetes mellitus.

Animals↗
PubMed1992

Prophylaxis of vitamin K deficiency in infancy.

A prospective study was performed in Okazaki, Japan, to attempt to establish a more effective system of prophylaxis for vitamin K deficiency in infancy (VKDI). During the first year, a Normotest (Hepaplastintest) was performed in all infants at one week and at one month of age. Two mg of vitamin K was administered orally to those whose Normotest values were below 40%. i.e., the non-prophylactic administration of vitamin K (NPVK). During the second year of the study, all newborn infants received prophylactic vitamin K (PVK) within 24 hours of birth and at one week of age. The dosage was repeated at one month of age depending on the Normotest value. A total of 7,059 infants, comprising 93.3% of the live births in the city of Okazaki, were enrolled in this study. Data from 5,431 of these infants were used in the analysis of the results. In the NPVK group, 20 of the 2,791 infants had Normotest values below 40% at one month of age while 20 of the 2,640 in the PVK group had low values despite the prophylactic administration of vitamin K. Considering the prevalence of low Normotest values (less than or equal to 40%) at one month of age and the predicted Normotest values, it was concluded that the month of birth (June-September), the age of the mother (21-29 years), the birth order (first-born) and male sex are risk factors for vitamin K deficiency in infancy.

Adult↗