Biomedical subjects

H Kubo

Publications and source records attributed to H Kubo.

At least 19 recordsLinked to original sources

PubMed1992

Senile cataract-related accumulation of Lewis(x) glycolipid in human lens.

A glycosphingolipid that reacted positively to anti-stage-specific embryonic antigen-1 (SSEA-1) antiserum accumulated in human lens in association with aging and senile cataract formation. Since this antiserum recognizes Lewis(x) (Le(x)) structure, Gal beta 1-4(Fuc alpha 1-3)GlcNAc-, which is a typical tumor-associated and differentiation-related saccharide chain, the lens glycolipid was predicted to be a Lex antigen. The glycolipid purified from cataractous lens tissues was indeed a Lex glycolipid, Gal beta 1-4(Fuc alpha 1-3)GlcNAc beta 1-3Gal beta 1- 4Glc beta 1-1 ceramide. Enhanced expression of the Lex glycolipid may affect the organization of lens plasma membranes through Le(x)-Le(x) interactions, as suggested for compaction in mouse preimplantation embryos and embryonic teratocarcinomas, resulting in lens opacification, namely cataract.

Cataract↗

PubMed1992

[The effect of nicardipine on angiogenesis in vitro].

We studied the effect of nicardipine, a calcium channel blocker, on the morphological change of endothelial cells in vitro. Cultured endothelial cells derived from bovine carotid artery make tubular structures between collagen gel layers. Tube formation of endothelial cells was suppressed by culture with 10(-9)-10(-5) M of nicardipine in a dose dependent manner. Migration of endothelial cells was also suppressed by the same dose of nicardipine. However, proliferation of endothelial cells was not enhanced. These findings suggest that nicardipine acts as an inhibitor of angiogenesis in vitro by inhibiting the migration of endothelial cells.

Animals↗

PubMed1992

Verification of treatment plans by mathematical formulas for single catheter HDR brachytherapy.

In high dose-rate brachytherapy, 500 to 1000 cGy will be given in a matter of minutes. Therefore, careful treatment planning and accurate verification of the plan is critical. To expedite the plan verification procedure, simple mathematical formulas were derived in our previous paper for single catheter treatments on a Nucletron microSelectron system. In this paper, the usefulness and limitations of these formulas for the plan verification procedure are further discussed.

Adult↗

PubMed1992

A novel ceramide trihexoside from the eggs of the sea urchin, Hemicentrotus pulcherrimus.

Glucosylceramide (Glc beta 1-1Cer) and a novel ceramide trihexoside (Gal beta 1-6Gal beta 1-6Glc beta 1-1Cer) were purified from the eggs of the sea urchin, Hemicentrotus pulcherrimus. Their chemical structures were determined by gas-liquid chromatography, methylation analysis, chromic acid oxidation, enzymatic hydrolysis, enzyme-linked immunosorbent assay, fast atom bombardment mass spectrometry, and proton nuclear magnetic resonance spectroscopy. The ceramide trihexoside has a novel carbohydrate structure, and its core structure, Gal beta 1-6Glc, is also novel. The ceramide moieties of these glycolipids are almost identical. Two fatty acids, 22:1 and 22h:1, constitute more than 80% of the total acids. Long-chain bases are all phytosphingosine, approximately 90% of which is n-t18:0. The finding of melibiosylceramide (Gal alpha 1-6Glc beta 1-1Cer) from the eggs of another sea urchin species [Kubo, H. et al. (1988) J. Biochem. 104, 755-760] and the present finding of the novel ceramide trihexoside suggest that there are a variety of unique sugar structures in sea urchin glycosphingolipids.

Animals↗

PubMed1992

A novel difucosylated neutral glycosphingolipid from the eggs of the sea urchin, Hemicentrotus pulcherrimus: I. Purification and structural determination of the glycolipid.

A novel fucose-containing neutral glycosphingolipid (GL-5) was purified from the eggs of the sea urchin, Hemicentrotus pulcherrimus. The chemical structure was determined to be Fuc alpha 1-3GalNAc beta 1-4(Fuc alpha 1-3)GlcNAc beta 1-4Glc beta 1-1Cer by methylation analysis, partial acid hydrolysis, fast atom bombardment mass spectrometry, and proton nuclear magnetic resonance spectroscopy. The unique characteristics of GL-5 are that: the reducing terminal disaccharide portion is not Gal beta 1-4Glc but GlcNAc beta 1-4Glc; it includes a GalNAc beta 1-4GlcNAc sequence and a Fuc-GalNAc linkage; the defucosylated core is a novel trisaccharide chain; and the sugar structure is one of the smallest ever characterized for a difucosylated glycolipid. The major fatty acids were 22:1 and 22h:1, and about 30% of the total acids was 2-hydroxylated. All the long-chain bases were phytosphingosines, of which about 90% was n-t18:0. The similarity of the ceramide moiety to that of glucosylceramide from the same eggs [Kubo, H. et al. (1992) J. Biochem. 111, 726-731] suggests a close biosynthetic relationship between GL-5 and the glucosylceramide.

Animals↗

PubMed1992

A novel difucosylated neutral glycosphingolipid from the eggs of the sea urchin, Hemicentrotus pulcherrimus: II. Structural determination by two-dimensional NMR.

A novel fucosylglycolipid from the eggs of the sea urchin, Hemicentrotus pulcherrimus, was determined by using two-dimensional NMR methods. Subspectra extraction by the homonuclear Hartmann-Hahn method was useful for identification of the individual sugar components. The homonuclear Hartmann-Hahn and double-quantum-filtered correlated spectra were analyzed to establish the assignments of sugar proton resonances. On the basis of the resonance assignments, the linkages of the individual sugar components were determined to be as follows. [formula: see text] This glycolipid contains a novel skeletal structure with the linkages of GalNAc beta 1-4GlcNAc beta 1-4Glc beta. We also observed that 2-hydroxylation of the fatty acids induced appreciable chemical shift changes of the proton resonances of the phytosphingosine moiety as well as the anomeric proton resonance of the reducing terminal glucose.

Animals↗

PubMed1992

Effects of nicardipine on tube formation of bovine vascular endothelial cells in vitro.

BACKGROUND AND PURPOSE: The purpose of this study was to assess the effect of nicardipine, a Ca2+ channel blocker, on angiogenesis in vitro. METHODS: Bovine carotid artery endothelial cells were cultured between type I collagen gel layers with 10(-9) to 10(-5) M nicardipine. The morphological changes were monitored by phase-contrast microscopy and photographed. The total length of tubular structures was measured with an image analyzer system. Endothelial proliferation and migration assays were also performed with the same doses of nicardipine. RESULTS: Cultured endothelial cells form tubular structures between collagen gel layers. Tube formation of endothelial cells was suppressed by culture with 10(-9) to 10(-5) M nicardipine in a dose-dependent manner. Migration of endothelial cells was also suppressed by the same doses of nicardipine. However, proliferation of endothelial cells was not enhanced. CONCLUSIONS: Nicardipine acts as an inhibitor of angiogenesis in vitro by inhibiting the migration of endothelial cells. This result suggests that nicardipine may have therapeutic potential in angiogenic disorders such as tumor growth, atherogenesis, and diabetic retinopathy.

Animals↗

PubMed1992

Preventive effect of exercise training on recurrent stenosis after percutaneous transluminal coronary angioplasty (PTCA).

The purpose of this study is to evaluate whether exercise training for 12 weeks prevents the development of restenosis after percutaneous transluminal coronary angioplasty (PTCA). Symptom-limited treadmill exercise with thallium-201 myocardial single photon emission computed tomography (SPECT) was performed one and 13 weeks after PTCA in 18 patients with exercise training and in 20 patients without. For quantitative analysis, the average count of region of interest in the hypoperfused area on the polar map was calculated. A percentage T1 uptake was determined by dividing average count of the hypoperfused area by that of a normal reference area at an initial image (%IU) and a delayed image (%DU). A percentage redistribution (%RD) was obtained by subtracting %IU from %DU as the parameter of residual ischemia in the hypoperfused area. Total treadmill exercise duration and maximal pressure rate product 13 weeks after PTCA increased significantly (p less than 0.01) in the trained group, whereas there was no significant change in the untrained group. %DU increased significantly (p less than 0.01) in the trained group, whereas there was no significant change in the untrained group. %RD decreased significantly (p less than 0.01) in the trained group, whereas there was no significant changes in the untrained group. The restenosis rates at the third month after PTCA was 17% (3/18) in the trained group and 40% (8/20) in the untrained group. These findings suggest that in patients with coronary artery disease exercise training improves myocardial perfusion by preventing the progression of coronary artery stenosis after PTCA.

Aged↗

PubMed1992

Migration of neutrophils from the lung into the pleural space after lung resection in humans and rabbits.

The origin of neutrophils that are found in pleural effusions after pulmonary resection is unknown. We measured neutrophil counts in pleural effusion sequentially for 48 h in patients who had undergone partial resection or pneumonectomy. Additionally, we measured neutrophil counts in the pleural effusions separately from the visceral pleura and parietal pleura in rabbits. In humans, we found that the maximum neutrophil counts in pleural effusion occurred more often in the patients who underwent partial resection (11.7 +/- 6.0 x 10(4) cells/microL) than in the patients who underwent pneumonectomy (3.7 +/- 1.2 x 10(4) cells/microL). There was no difference between neutrophil counts in blood of pneumonectomy group and that of the partial resection group. In rabbits, neutrophil counts were 1.5 times greater in the pleural effusion derived from the lung than in that derived from the parietal pleura. We conclude that movement of neutrophils occurs primarily from the lung into the pleural space after lung resection in humans and rabbits.

Animals↗

PubMed1992

Rapid morphological changes in bovine brain microvascular endothelial cells on extracellular matrices.

The morphological changes in endothelial cells derived from bovine brain microvasculature, carotid artery, and aorta during growth on extracellular matrices were compared. All cells formed tubular structures on a basement membrane. Ultrastructural studies showed that the tubular structures had lumens surrounded by many endothelial cells. On type I collagen gel, brain microvascular endothelial cells still formed tubular structures, but the other two cell types formed confluent monolayers. However, when a second layer of collagen gel was laid over these cells, tubular structures developed within 2-3 days. Brain microvascular endothelial cells form tubular structures more readily than endothelial cells derived from large vessels on both basement membrane and type I collagen gel.

Animals↗

PubMed1992

[Contributing factors to intellectual impairment in patients with multiple lacunar infarctions].

The author investigated factors leading to intellectual impairment in patients with multiple lacunar infarctions. The subjects consisted of 40 patients with multi-infarct dementia (MID) and 17 nondemented patients with multiple infarctions (MI) who showed multiple lacunar infarctions in the deep penetrating arterial territory on CT. MID patients showed more marked and extensive periventricular lucency (PVL), a higher degree of ventricular index (VI) measured on CT, and were of a higher age, and had poorer activity of daily living (ADL) compared with MI patients. There were significant correlations between the PVL score, VI, ADL score, age and Hasegawa's dementia rating score (HDS). However, no significant differences in sex, site of infarct, and the count of low density areas reflected lacunar infarction on CT, and vascular risk factors were shown between MID and MI patients. Multiple regression analysis demonstrated that the PVL score and VI showed the highest partial correlations for HDS, and that the ADL score and age were also independently contributing factors. Our results suggest that deep white matter lesions observed as PVL on CT and ventricular enlargement were the most important factors contributing to intellectual impairment in patients with multiple lacunar infarcts, and that physical factors such as ADL and age can be considered to be related to the development of dementia.

Activities of Daily Living↗

PubMed1992

[Effects of exercise training on restoration of residual myocardial ischemia after percutaneous transluminal coronary angioplasty].

The effects of exercise training on the restoration of hibernating myocardium after percutaneous transluminal coronary angioplasty (PTCA) were evaluated. Symptom-limited treadmill exercise with thallium-201 myocardial single photon emission CT (SPECT) was performed at one and 13 weeks after PTCA in 15 patients with training and in 15 control patients without training who had no restenosis on repeat angiography. For quantitative analysis, counts for the regions of interest (ROI) were calculated in the hypoperfused area on the polar map. Percent T1 uptake was determined by dividing counts of the hypoperfused area by counts of a normal reference area on the initial image (%IU) and delayed image (%DU). The difference between %DU and %IU, defined as percent redistribution (%RD), was a parameter of residual ischemia in the hypoperfused area. %DU increased significantly in the trained group (65 +/- 11 to 73 +/- 9.3%, p < 0.01) and in the untrained group (66 +/- 14 to 70 +/- 15%, p < 0.05). %RD decreased significantly in the trained group (6.3 +/- 3.2 to 2.8 +/- 2.3%, p < 0.01); whereas, there was no significant change in the untrained group (6.1 +/- 2.8 to 5.2 +/- 3.8%). These findings suggest that, after successful PTCA, exercise training helps alleviate myocardial ischemia, probably by fostering the promoting effects which restore the hibernating myocardium.

Aged↗

PubMed1992

[Rapid morphogenesis of brain microvascular endothelial cells in culture system].

Endothelial cells of bovine brain microvascular vessels (BBECs), carotid artery (BCECs) and aorta (BAECs) were cultured on type I collagen and Matrigel. BBECs make tubular structures and BCECs and BAECs grow and make confluent monolayer on type I collagen gel. But BCECs and BAECs make tubular structures when second layer was overlaid. BBECs, BCECs and BAECs make tubular structures on Matrigel. These morphological changes were not affected by basic fibroblast growth factor. These results suggest that BBECs have more potent angiogenic ability than BCECs and BAECs.

Animals↗

PubMed1992

[A case of tracheobronchopathia osteoplastica discovered after difficulty in intubation].

A 77-year-old man was scheduled for Love's method to correct lumbar disc herniation. He had fracture of maxilla and mandibula during World War II. Physical examination and laboratory data revealed no abnormalities. Anesthesia was induced with oxygen, nitrous oxide and halothane. Following administration of succinylcholine, an attempt was made to insert a tracheal tube (from 8.5mm to 5.5mm), but the tubes were met with an obstruction. The operation was cancelled because tumor-like nodules were seen in the trachea. Diagnosis of tracheobronchopathia osteoplastica was made afterwards following biopsy. The patient with this disease has a good prognosis. Artificial ventilation can be performed safely by choosing an appropriate method for airway maintenance.

Aged↗

PubMed1992

Exercise training and the prevention of restenosis after percutaneous transluminal coronary angioplasty (PTCA).

To evaluate whether exercise training prevents the restenosis after percutaneous transluminal coronary angioplasty (PTCA), treadmill exercise with thallium-201 myocardial scintigraphy was performed at first and thirteenth week after PTCA in 18 patients with training and in 20 patients without training. Total treadmill exercise duration and maximal pressure rate product 13 weeks after PTCA increased significantly in the trained group, whereas there was no significant change in the untrained group. ST segment depression from the baseline did not change significantly in both groups. Myocardial perfusion obtained by Tl-201 scintigraphy improved significantly in the trained group, whereas there was no significant change in the untrained group. The restenosis rates at the third month after PTCA was 17% (3/18) in the trained group and 40% (8/20) in the untrained group. It is concluded that in patients with coronary artery disease, exercise training improves myocardial perfusion by preventing the progression of coronary artery stenosis after PTCA.

Angioplasty, Balloon, Coronary↗

PubMed1992

[Analysis of cell proliferation kinetics and the effects of cisplatin on the cell cycle of human gastric cancer cells by autostage cytofluorometry].

Analysis of both cell proliferation kinetics and effects of cis-diamminedichloroplatinum (CDDP) on cell cycle in human gastric cancer cell line (HGC-Y2) by measuring the contents of nuclear DNA, RNA and the Ki-67 antigen using autostage cytofluorometry system was described. In HGC-Y2 cells, RNA content increased during the cell cycle and reached to the maximum at G2/M phase. The results of pulse treatment with CDDP on these cells demonstrated a prolongation of S phase and G2 arrest with increasing of RNA content of these cells. We classified the cells by intranuclear distribution pattern of Ki-67 antigen and thus could identified the cells at G0 and M phases from these classification. The content of Ki-67 antigen was moderate grade at G1 phase and it decreased in the early S phase, then increased gradually during S phase and at the late S phase. It increased rapidly, reaching to the maximum at G2/M phase. After CDDP treatment, the content of Ki-67 antigen increased in the cells in prolonged S phase and in the cells arrested at G2 phase. It was also found that the syntheses of both Ki-67 antigen and RNA were not inhibited by CDDP. These results suggest that the method using autostage cytofluorometry system was useful for the research, on the mechanism of cancer therapy because of making possible to analyze precisely the cell cycle and the influence of anticancer drugs.

Cell Cycle↗

PubMed1991

Developmental change in ganglioside expression in primary culture of rat neurons.

Developmental changes in ganglioside levels and patterns were investigated in neuronal cells dissociated from 17-day-old fetal rat hemispheres for up to 7 days of culture. Increases in ganglioside contents and the onset of GM3 synthesis, which is associated with proliferation of glial cells, were observed as the neuronal network was established in cell cultures. The distribution of gangliosides in developing neurons was monitored by the indirect immunofluorescent technique using three anti-ganglioside antibodies. Anti-GM1 antibody showed immunofluorescence only on the cell soma 1 and 3 days after plating and additional binding between cell aggregates by 7 days in culture. GD3 ganglioside, the predominant species in embryonic neurons, was not detected on the neuronal cell surface, whereas the number of positively stained non-neuronal cells was increased at 7 days. Monoclonal A2B5 antibody suggested that polysialogangliosides play a role in neuronal network formation. In 1-day-old culture, however, all antibodies bound poorly to cell surface antigens and strongly to cells, the membranes of which were permeabilized with acetone. These results suggest that a substantial amount of gangliosides are retained, transformed within the cell to more complex gangliosides, and translocated to the cell surface following neurite outgrowth and morphological changes.

Animals↗

PubMed1991

Bestatin administration and the change in cellular immunity.

The change in cellular immunity by Bestatin (ubenimex) treatment--30 mg/day orally--was investigated in 23 gastrointestinal cancer patients for: 1), functional T cell subsets; 2), IL-2 receptor; 3), PHA-induced blastogenesis; and 4), PPD skin reaction. The absolute number of helper T cells (Th) and cytotoxic T cells (Tc) increased in 74 and 79% of cases, respectively, compared with pretreatment values. On the other hand, the absolute number of suppressor T cells (Ts) decreased in 79% of cases. IL-2 receptor increased in 56% of patients, PHA blastogenesis increased in 67% of patients and PPD skin reaction was elevated in 75% of cases comparing to pretreatment values. These results suggest that Bestatin could increase cellular immunity in cancer patients.

Antibiotics, Antineoplastic↗