Search PubMed⌕ Search

Biomedical subjects

H Kubo

Publications and source records attributed to H Kubo.

447 records · Page 25Linked to original sources

Ngas values of the Memorial parallel-plate chambers determined in 60Co and high-energy electron beams.

The cavity-gas calibration factor Ngas for Memorial parallel-plate chambers was determined against calibrated Farmer chambers using two different calibration methods as suggested in the TG 21 protocol. These methods are: (a) 60Co calibration at 5-cm depth; and (b) high-energy electron beam calibration. The Ngas values determined from the 60Co in-phantom calibrations were approximately 1.9% higher than the values determined from the high-energy electron beams.

Cobalt Radioisotopes↗

Evaluations of two solid water parallel-plate chambers in high-energy photon and electron beams.

Using high-energy photon and electron beams, the response of two solid water parallel-plate chambers is evaluated against a PTW (Physicallsch-Technische Werkstatten) Farmer-type chamber. These two chambers are (1) a Memorial "Holt" chamber which was further modified by this author to take advantage of electrically conductive solid water, and (2) a thin window parallel-plate chamber designed by Attix. The evaluations are made for (1) stability and reproducibility, (2) polarity effect, (3) ion recombination correction, (4) field size dependence on output, (5) dose rate dependence on output, and (6) absorbed dose comparison in high-energy photon and electron beams using the American Association of Physicists in Medicine Task Group 21 (TG21) protocol.

Electrons↗

Cytotoxic properties of eosinophil granule major basic protein for tumor cells.

BACKGROUND: Eosinophil granule major basic protein (MBP) mediates many eosinophil-associated immune functions and it adheres eosinophils to parasite targets. METHODS: We compared the toxicities of MBP and melittin to K562 and HL-60 cells using five cytotoxicity methods. RESULTS: Trypan blue staining, propidium iodide/ CellTrackertrade markGreen staining and incorporation of 14C-leucine assays indicated that MBP damages most cells by 1 h. In contrast, 51Cr and lactic dehydrogenase (LDH) release assays indicated that MBP damages most cells only at 20 h. All five methods indicated that melittin damages nearly all cells by 1 h. To resolve these discrepancies, the procedures were modified. Without cell transfer, dye staining methods showed that MBP produces very little cytotoxicity at 4 h. 51Cr and LDH assays, modified to mimic cell transfer, showed increased cytotoxicities at 4 h. The 14C-leucine assay modified by solubilization of cells with SDS and by trichloroacetic acid precipitation showed increased recovery of labeled protein and, thus, lower cytotoxicity, about 50%, at 4 h. CONCLUSION: Overall, MBP's ability to cause molecular and cellular adhesion confounds cytotoxicity measurements. A modified 14C-leucine assay overcame MBP's adhesiveness and provided an accurate measure of cytotoxicity.

Blood Proteins↗

Prenatal diagnosis of Duchenne muscular dystrophy by polymerase chain reaction analysis.

The efficacy of the polymerase chain reaction (PCR) in the first-trimester prenatal diagnosis of Duchenne muscular dystrophy (DMD) was examined. Twenty-seven fetuses from 26 Japanese pedigrees at risk for DMD were analyzed. PCR-restriction fragment length polymorphism analysis, multiplex PCR, and dinucleotide repeat polymorphism analysis were used. Of 16 males, 11 were determined to be unaffected, 4 were affected, and the remaining 1 was undetermined. Of the 11 female fetuses, 1 was diagnosed as a noncarrier, 4 were carriers, and the carrier status of the remaining 6 was not determined at the option of the patients, although DNA polymorphisms could be detected in those patients. Prenatal diagnosis by PCR analysis was possible in 96% of the fetuses tested (26 of 27).

Exons↗

Effect of AA-2414 on early and late bronchial responses in actively sensitized guinea-pigs.

The effect of a new thromboxane A2 receptor antagonist, AA-2414, (+/-)-7-(3,5,6-trimethyl-1,4-benzoquinon-2-yl)-7-phenylheptanoic acid, on dual bronchoconstriction and airway hyper-reactivity in actively sensitized guinea-pigs was investigated. Immediate and late bronchial responses were seen 1-10 min and 4-7 h, respectively, after inhalation of antigen. In guinea-pigs pretreated with AA-2414, 5 mg/kg orally, the immediate bronchial response was inhibited. An administration of AA-2414 inhibited the late bronchial response. The numbers of eosinophils, neutrophils and macrophages, but not of lymphocytes, in bronchoalveolar lavage fluid were increased at 4 h after antigen inhalation. AA-2414 did not affect the numbers of total cells, eosinophils, neutrophils or macrophages. Sensitized guinea-pigs showed a significant airway hyperreactivity to inhaled histamine, which was not influenced by an administration of AA-2414. Luminol-dependent chemiluminescence of airway-infiltrated cells from sensitized guinea-pigs stimulated with A23187 was slightly inhibited by AA-2414. These results show that AA-2414 inhibits the late asthmatic response and the production of oxygen radicals from airway-infiltrated cells.

Animals↗

Influence of theophylline on activated lymphocytes and eosinophils in peripheral blood and sputum.

The influence of a once-a-day sustained-release theophylline (Uniphyl) on lymphocytes and eosinophils in the peripheral blood and sputum of patients with bronchial asthma was investigated. The peripheral blood lymphocytes included CD4, CD8, CD25 and HLA-DR. The sputum lymphocytes and eosinophils included CD4, CD8, CD25 and HLA-DR, and EG2, respectively. The results revealed that theophylline administration did not affect the numbers of activated CD4 and CD8 T lymphocytes in peripheral blood. No significant change in the lymphocyte count was observed in sputum, but the eosinophil count in the sputum decreased significantly after theophylline administration. EG2-positive eosinophils also decreased in number. CD4+HLA-DR+ and CD4+CD25+ T lymphocytes were significantly decreased, whereas CD8+ T lymphocytes in the sputum were not significantly reduced in number. Respiratory function test showed that forced expiratory volume in 1 s was significantly increased after theophylline administration. The results suggest that a new once-a-day sustained-release theophylline formulation would be useful in the treatment of chronic respiratory tract inflammation.

Asthma↗

Effects of saiboku-to on dual-phase bronchoconstriction in asthmatic guinea pigs.

In recent years, bronchial asthma has come to be regarded pathologically as a chronic inflammatory disease of the respiratory tract. Inhalational steroids and antiinflammatory drugs are recognized as being effective against bronchial asthma. In this study, the effects of Saiboku-to, a Chinese herbal (Kampo) formulation, were investigated on asthmatic guinea pigs sensitized to ovalbumin (OA). Following 7-day administration of Saiboku-to (500 micrograms/kg), the late asthmatic response (LAR) to an antigen challenge was found to be inhibited. The number of eosinophils in fluid obtained by bronchoalveolar lavage (BAL) 4 h after antigen challenge was decreased while the infiltration of eosinophils and T-lymphocytes into the lung parenchyma was inhibited. These findings suggest that Saiboku-to has the potential to become a useful drug in the treatment of bronchial asthma.

Animals↗

Role of substance P in increased airway hypersensitivity following induced stress in a guinea pig asthma model.

Stress is one of the important factors influencing bronchial asthma, but many questions still remain unanswered. To clarify this point we examined airway hypersensitivity before and after electric shock stress and the role of substance P in an animal model of asthma. We determined airway hypersensitivity to histamine and the substance P levels in serum, bronchoalveolar lavage fluid, and bronchial tissue before and after electric shock stress in biphasic asthma-responsive guinea pigs which had been sensitized using ovalbumin. The cell components in bronchoalveolar lavage fluid were also examined. Airway hypersensitivity to histamine (4.9-156 micrograms/ml) was significantly increased (p < 0.01) by electric shock stress. The substance P level was also significantly increased in plasma and bronchoalveolar lavage fluid, but it was significantly decreased in bronchial tissue. The number of eosinophils in bronchoalveolar lavage fluid increased significantly after electric shock stress. These findings demonstrated that airway hypersensitivity to histamine was increased by stress and suggested that substance P, as well as eosinophils, contribute to the pathogenesis of hypersensitivity.

Animals↗

Endosonographic probe-guided endoscopic removal of colonic pedunculated leiomyoma.

We report a rare case of endoscopic removal of colonic pedunculated leiomyoma with an aid of endoscopic ultrasonography (EUS). A 46-year-old man was admitted to our hospital with complaints of lower abdominal pain and alternating constipation and diarrhea. Colonoscopy revealed a small pedunculated polyp in the transverse colon covered with almost normal mucosa. EUS showed a hypoechoic solid tumor with clear margins and smooth contour in the second to third layer. We considered this lesion as a submucosal tumor of the colon with no continuity to the muscularis propria. We performed endoscopic removal of this tumor successfully, and histological diagnosis was a leiomyoma. Endoscopic removal of colonic pedunculated leiomyoma is rare. Moreover, in our case, EUS showed typical findings of colonic leiomyoma and was useful to assess the location of the submucosal tumor. We describe herein our experience and discuss similar cases reported in the English literature.

Colonic Neoplasms↗

Primary hepatic carcinoid tumor: case report and review of 53 cases.

BACKGROUND: Primary hepatic carcinoid tumor (PHCT) is a extremely rare. The authors describe a patient with PHCT and review previously published cases of the disease. CASE REPORT: A 75-year-old man, presenting with weight loss and pain in the right upper abdomen, had multiple masses in both lobes of the liver. He was diagnosed as PHCT by radiological examination, laboratory findings with high levels of 5-hydroxyindoleacetic acid (5-HIAA) in the serum and urine, and histological findings including positive staining of tumor cells for Grimelius and chromogranin A. The patient received totally transcatheter arterial chemoembolization (TACE) five times over 27 months; this treatment provided excellent palliation and caused a decrease in urinary 5-HIAA levels. Fifty-three cases of PHCT have been reported in the English-language literature. RESULTS: Analysis of these published cases revealed that PHCT occurs in the middle age (mean age = 48.2 years) and is more frequent in females (males/females = 20/33 cases). Of the symptomatic patients, the major findings is abdominal pain, fullness, and/or a palpable mass (56% of symptomatic patients). In contrast, only 2 cases out of 53 presented with symptoms of typical carcinoid syndrome. In most cases, PHCT was detected as a hypervascular lesion by radiological examination. By histological analysis, 80% and 84% of the cases were positive for Grimelius silver stain and immunohistochemically positive for chromogranin A, respectively. Surgical resection is the treatment primarily recommended with an 18% of recurrence rate and a 74% of a survival rate after 5 years. For unresectable and recurrent cases, TACE may be recommended.

Aged↗

Cytologic studies of malignant melanoma of the vagina.

Four cases of primary malignant melanoma of the vagina are described and discussed with respect to vaginal smears. Two cases treated with radiotherapy began to increase the amount of the melanin pigment during the course of irradiation. Characteristic cytologic features found in the four cases are summarized as follows: a) Distribution of cell 1) Scattering, no tendency of grouping 2) Moderate anisocytosis and anisokaryosis b) Cytoplasm 1) Cyanophilic wispy cytoplasm 2) Indistinct cytoplasmic rim 3) Relatively clear cytoplasm 4) Relatively low N/C ratio c) Melanin pigment 1) In melanoma cells-finely granular and diffusely packed in cytoplasm 2) In histiocytes-coarsely granular and densely packed in cytoplasm d) Nucleus 1) Extremely eccentric nucleus 2) Thin and irregular nuclear membrane 3) Relatively regular chromatin distribution 4) Finely or moderately granular chromatin pattern 5) Prominent nucleolus 6) Giant malignant cells (3-4 nuclei) 7) Intranuclear vacuole (punched out).

Adult↗

Facile and definitive determination of human adriamycin and daunoribicin metabolites by high-pressure liquid chromatography.

Adriamycin and eight metabolites were separated and characterized with an ammonium formate/tetrahydrofuran solvent system on a muBondapak-Phenyl column. Danorubicin and seven daunorubicin metabolites were separated and characterized by the same method. Adriamycin and its major metabolite, adriamycinol, were extracted with 50-70% efficiency from human plasma with chloroform/2-propanol (1:1) and quantified against a daunorubicin internal standard. Urinary concentrations of parent drug, adriamycinol, and the 4-O-sulfate were determined as well. Daunorubicin and daunorubicinol were extracted from human plasma and quantified against an adriamycinol internal standard. The fluorescence detection system has a detection limit of 1.0 pmol, and levels as low as 25 mmol/ml are measurable in plasma.

Chromatography, High Pressure Liquid↗

A case of retroperitoneal pseudomyxoma.

We experienced a rare case of pseudomyxoma that progressed into the retroperitoneum. This patient presented with complaints of polyuria and back pain. CT and MRI showed a retroperitoneal cystic tumor. Surgical and pathological findings confirmed mucinous cystadenoma of the appendix that reached the posterior space behind the right kidney through the retroperitoneum.

Appendiceal Neoplasms↗