Biomedical subjects
Publications and source records attributed to Y Okamoto.
Density gradient centrifugation using Ficoll-Conray solution was attempted to isolate viable canine transmissible sarcoma (CTS) cells. The viability of isolated tumor cells increased from about 50% to > 90%, and the yield of CTS cells was > 50% with over 99% purity, in when an isolation solution density of 1.05 was used.
The absolute potential value of Wilson's central terminal was calculated at 2 msec intervals during a cardiac cycle in 60 clinical cases. Starting from the body surface potential data at 128 thoracic locations, the effect of immersion of the body into an infinite conductor on the surface potential was calculated to obtain values with reference to zero potential at infinity. The conductivity of the outside medium was then made to approach zero. Comparison of the result with the original map showed nearly a constant shift of the potential, corresponding to the voltage of Wilson's terminal. In addition, the cardiac vector was calculated as the first approximation of the cardiac electromotive force and the lead vector of Wilson's terminal was obtained in order that the scalar product of the cardiac vector and the lead vector approximated the observed voltage of Wilson's terminal. The results indicate that the voltage of the Wilson electrode depended on the surface voltage with a peak value near the maximal QRS force in most of the cases. The peak voltage of Wilson's terminal was either positive or negative, and was 0.15 mV in absolute value on average. Voltage variations of Wilson's terminal during a cardiac cycle were 0.20 mV as an average of all cases. The voltage of Wilson's terminal also depended on the direction of the equivalent cardiac vector. The lead vector of Wilson's terminal was found to be directed superiorly in most of the cases. The average magnitude of the lead vector of Wilson's terminal was 0.097 omega/cm, which corresponded to about 1/4 of that of lead I.
To evaluate the validity of the recall method in estimating food intake in the distant past, we assessed past and current food intakes by mailed food questionnaires among 80 residents in Gifu, Japan who had answered the same questionnaire 9 years ago. We compared rank correlations and differences between recalled food intake scores and past ones with those between current food intake scores and past ones. We observed higher scores of recalled intake for meat, potatoes and alcohol, and a lower score of recalled intake for cereals than the scores of past intake. We observed increase in food intake scores of soyabean products, dairy products and potatoes and decrease in that of cereals intakes from past to current. The rank correlation coefficients between the recalled and past food intake scores (r = 0.24-0.89) were greater than those between the current and past ones (r = 0.10-0.70) for every food item except for dairy products. After stratification by sex, age and degree of change in body mass index (BMI), the greater correlation between the recalled and past food intake scores remained. These findings suggest that the recall method is more preferable than the current data to estimate food intake in the distant past in Japan.
Carotid ligation and vascular reconstruction following radical neck dissection were required in a patient with carotid artery rupture associated with an infected salivary fistula. An extracranial-intracranial high-flow bypass was performed using a radial arterial graft between the V3 segment of the vertebral artery and the M2 segment of the middle cerebral artery. Postoperative angiograms confirmed sufficient blood flow through the bypass graft into the ipsilateral internal carotid arterial system. No clinical signs of ischemia were observed postoperatively. This V3-M2 bypass procedure appears to be an effective means of controlling catastrophic bleeding from a ruptured carotid artery, thus allowing the wound to heal completely.
We measured concentrations of interleukin-8 (IL-8) in sputum from 38 patients with pulmonary emphysema, from 30 patients with bronchial asthma, and in induced sputum from 10 healthy subjects. Concentrations of IL-8 were significantly higher in sputum from patients with emphysema than in sputum from patients with asthma (mean +/- SE: 22,961 +/- 1,412 pg/ml and 9,135 +/- 1,590 pg/ml, respectively, p<0.0001) and were also higher than in sputum from healthy subjects (3,253+/-687 pg/ml, p<0.0001). Concentrations of IL-8 in sputum from patients with emphysema were unrelated to whether the patient was a current smoker or an ex-smoker, and did not correlate with concentrations of IL-8 in serum. Concentrations of IL-8 in sputum from patients with emphysema correlated significantly with FEV1% (r=-0.78, p<0.0001) and with %RV/TLC (r=0.63, p<0.01). These data suggest that IL-8 is mainly involved in chronic airway inflammation and that concentrations of IL-8 in sputum are closely related to airflow obstruction in patients with pulmonary emphysema.
In the current study, endothelin-1 (ET-1) worked as a mitogen on Chinese hamster ovary cells stably expressing human endothelinA; when applied to serum-deprived cells, ET-1 caused dose-dependent increase in [3H]thymidine incorporation and cell proliferation. No synergism was observed between the effect of ET-1 and that of insulin-like growth factor-1/basic fibroblast growth factor. Both the inhibition of intracellular Ca2+ response by phospholipase C inhibitor U73122 and the down-regulation of protein kinase C (PKC) by pretreatment with phorbol 12-myristate-13-acetate (PMA) partially blocked the ET-1-induced mitogenic responses. Wortmannin, a phosphatidylinositol-3-kinase inhibitor, caused dose-dependent inhibition of the ET-1-induced mitogenic responses in both PMA-treated and -untreated cells. Wortmannin also inhibited ET-1-induced increase in phosphatidylinositol trisphosphate formation and activation of mitogen-activated protein kinase (MAPK), whereas it failed to inhibit PMA-induced activation of MAPK. In accordance with its effect on MAPK activation, wortmannin inhibited ET-1-induced activation of Raf-B, whereas it failed to inhibit the effect of PMA. These results suggested the role of a Ca2+/PKC-independent, wortmannin-sensitive signaling pathway that linked ETA and MAPK cascade in the mitogenic signaling activated by ETA.
In Piaget's system, the development of children's cognitive structures is seen as progressing through a universal sequence from sensorimotor, to concrete, to formal logical thought. The data that have been obtained on his measures are problematic in their support for this view, however, because they indicate that adults in traditional societies often fail his formal tasks. Piaget's (1972) interpretation of such findings was that they indicated a problem with his measures, not his theory - if appropriate measures were available, he believed that formal logical operations would be found in all cultures and social groups. Our own interpretation differs. While we acknowledge that adults in all cultures are capable of thinking in a fashion that is more sophisticated, subtle, and complex than that of young children, we see the highest forms of thought as being dependent on the mastery of systems that are cultural creations and not universal human attainments - and we see Piaget's system of formal operations as being just one example of the sort of system that can be created by a culture and passed on from one generation to the next. In a previous investigation, Fiati (1992) studied children who were growing up in isolated, agricultural villages in the Volta region of West Africa. In these communities, life was still a traditional one, and children's experiences with time, money, and mathematical computation were considerably different from those of children who were attending schools in the nearby towns. Under these conditions, Fiati found that village children's skill in using numbers or in thinking about quantitative variables did not develop to a very high level as compared to that of their peers in the towns or as compared to their own thinking about social issues. In the terms used in the present Monograph, it appeared as though children's central conceptual structures for number - in contrast to their central conceptual structures for narrative - did not advance much past the unidimensional level. Are unidimensional structures, at least, universal? Very probably the answer to this question is yes. Although systems for counting, for example, vary widely, no culture has yet been found in which counting does not play some role or where young children fail to pass Piaget's conservation of number test (Saxe, 1988). It seems highly likely, therefore, that a mental counting line of some sort is a universal construction. The situation in the domain of narrative is quite similar. Although folktales vary widely from one culture to the next, no culture has been reported in which folktales play no role whatever or where the story line of existing folktales does not have some form of intentional component (Propp, 1922/1968). The mental story line may thus be a universal construction as well. Finally, no culture has been reported in which some form of decorative art is not present or in which no technology exists for launching a projectile along a desired trajectory. If these activities require a mental reference line of some sort, then this would be a candidate for universal conceptual attainment as well. In the present series of studies, our investigations were confined to societies that are modern, highly literate, and schooled. Thus, our interest was in demonstrating a universal progression well beyond the unidimensional level, in the sorts of structure that are crucial to life in a modern industrial culture. In fact, this was what we found in each of our studies. On our tests of central conceptual structures, children progressed through the same stages and at the same rate. By contrast, on our tests of more specific understanding, especially on those dealing with issues on which different cultures place different emphasis, we found large and significant cross-national differences. From this we conclude that, if a culture values a particular task or set of tasks and invests a great deal of effort in teaching them, it is likely that the
Cyclin and cyclin-dependent kinase(cdk) complexes, and their inhibitors (CKIs) play important roles in growth regulation on the cells. p27/kip1 is a CKI associated with G1 arrest induced by cell to cell contact, transforming growth factor-beta and cyclic AMP. The abnormality of p27/Kip1 genes in human tumors usually appears as a steady level defect of expression, since mutations in them is rare. Thus it is important to estimate the expression level of this gene. To detect the change of p27/Kip1 mRNA level in blood cells, we developed the ribonuclease protection assay using nonradioactive riboprobe which was produced by reverse transcriptase-polymerase chain reaction (RT-PCR) with T7 promoter-added antisense primer and the in vitro transcription system. Our assay may be useful for clinical evaluation of the mRNA level.
A 75-year-old female had loss of appetite, left hypochondrial and back pain. An X-ray and a computed tomogram of both lungs showed multiple small granular shadows. By Tc-labelled bone scintigram, multiple uptakes were found. Since high serum CA19-9 was obtained, pancreatic or bile duct cancer with multiple lung and bone metastasis was suspected. The autopsy revealed, small nodules in both lungs were well-differentiated adenocarcinoma, bronchiolo-alveolar type, and immunohistologically, tumor cells were stained positively for CA19-9. Since CA19-9 exists in normal bronchial glands and bronchiole, high level of serum CA19-9 in our patient may be derived from the neoplastic bronchiolar epithelium.
Altered nutrient intake and metabolism are responsible for the progressive loss of body weight observed in most patients with advanced cancer, but the precise mechanism is still controversial. Under stressful conditions, some inflammatory cytokines such as IL-1 beta, TNF alpha, and IL-6 have a hypermetabolic effect and cause proteolysis and lipolysis in muscle and in fat tissues. To elucidate the mechanism of malnutrition in patients with lung cancer and normal food intake, we focused on the relationship between abnormal metabolism and these inflammatory cytokines. Patients with lung cancer were confirmed to be malnourished, and this malnutrition was found to be caused by hypermetabolism as estimated with visceral proteins, plasma levels of amino acids, and anthropometric indices. The production of IL-1 beta, TNF alpha, and IL-6 by blood monocytes was significantly higher in these patients than in healthy controls, and it correlated significantly and inversely with indices of nutrition. The present results suggest that nutritional status and these cytokines are closely related in patients with lung cancer. IL-1 beta, TNF-alpha, and IL-6 may serve as anti-cancer bioactive molecules, but "overfunctioning" of these cytokines may induce a hypermetabolic status that causes malnutrition, i.e. cancer cachexia.
The genetic defect in a patient with hereditary type I protein S (PS) deficiency was investigated. All the exons and intron-exon junctions of the patient's PS gene were amplified by PCR and subjected to heteroduplex screening. Only the PCR product of exon 4 revealed heteroduplex bands. A novel nonsense mutation, Ser62 (TCA) to Stop (TGA) was found in exon 4. RT-PCR detected the aberrant mRNA in the patient's platelets, which was markedly reduced in amount and lacked the region of exon 4, suggesting that the nonsense mutation affected the mutated mRNA metabolism and induced exon skipping. The skipping of exon 4 causes an in-frame deletion of 29 amino acids which just construct the thrombin-sensitive region of the PS molecule. The loss of such an important domain as well as the quantitative decrease in the mutated mRNA appear to be responsible for the type I PS deficiency in this patient.
The purpose of this study was to investigate body composition in patients with chronic obstructive pulmonary disease, and its relation to pulmonary function. Seventeen men with pulmonary emphysema who were being treated as outpatients were divided into three groups, according to ideal body weight (IBW): group A, %IBW > or = 90%; group B, 90 > %IBM > or = 80; and group C, %IBW < 80. All underwent body composition analysis by dual energy X-ray absorptiometry. Fat mass and bone mineral content were significantly lower in groups B and C than in control subjects. Lean mass was significantly lower in group C than in control subjects. By contrast, group A did not differ significantly from control subjects. Lean mass correlated significantly with %VC, FEV1, RV/TLC, and MVV. These data suggest that lean mass is low in moderately and severely malnourished patients, that bone mineral content and fat mass are low in mildly malnourished patients, and that abnormal body composition is associated with ventilatory impairment in patients with chronic obstructive pulmonary disease.
The effects of nicorandil on coronary collateral circulation during exercise-induced ischemia were compared between the different donor arteries in 13 patients with effort angina, 7 with complete obstruction of the left anterior descending artery (LAD) with well-developed collateral vessels from the right coronary artery (RCA) (LAD group), and 6 with complete occlusion of the RCA (segment 2-3) with well-developed collateral vessels from the LAD (RCA group). Initial percentage thallium (%TI) uptake (thallium-201 single photon emission computed tomography) and washout rate were measured in the anterior, septal and posterior regions during ergometer exercise. The submaximal treadmill exercise test was also performed using a cardiopulmonary monitoring system to measure Vo2 at anaerobic threshold (AT). After the controls were obtained, nicorandil (15 mg/day) was administered for 4 weeks, during which ergometer exercise and treadmill exercise tests were carried out repeatedly. A significant improvement of initial %TI uptake on exercise was observed in the LAD group with nicorandil therapy, but no improvement was shown in the RCA group. The AT significantly increased after nicorandil treatment in the LAD group (13.9 +/- 0.38-->16.8 +/- 1.18 ml/min/kg), reflecting the improvement of cardiac function through the increased collateral flow. However, in the RCA group, it remained unchanged, suggesting no improvement of cardiac function. Nicorandil was effective to increase collateral flow from the RCA, but ineffective on that from the LAD. Nicorandil is an effective coronary dilator and is reported to affect both large and small coronary arteries. The effect on the collateral circulation is dependent on the donor artery supplying different areas. The vasodilator effect of nicorandil is mainly on the LAD, which is large enough to supply blood to a wider area of the heart, rather than the RCA.
In this report we have investigated the intracellular calcium (Ca2+) mobilization mediated by serotonin 5-HT2A receptors in the platelets of 13 patients with bipolar disorder and 12 patients with major depression in comparison with 15 healthy control subjects. We found an enhanced intracellular Ca2+ rise in response to 5-HT in platelets from both bipolar patients and patients with major depression. The 5-HT2A receptor-mediated intracellular Ca2+ signaling mechanism may have an important role in the pathophysiology of affective disorders.
In the present study, we evaluated the role of high-density lipoprotein (HDL) as an endotoxin-binding protein in chronically alcohol-fed rats. Although the blood endotoxin level was significantly elevated in chronic ethanol-loaded rats, compared with control rats, serum tumor necrosis factor (TNF), ALT, and lactate dehydrogenase were not elevated. Serum HDL and its endotoxin-binding capacity were significantly increased in chronic ethanol-loaded rats. When Kupffer cells isolated from control and chronic ethanol-loaded rats were cultured in the medium containing 3 to 30 mg/dl HDL and endotoxin (500 ng/ml), endotoxin uptake and TNF production of Kupffer cells were decreased in proportion to the concentration of HDL in the medium. These results suggest that the increase in endotoxin-binding capacity of HDL may serve as a protective mechanism against endotoxin in chronic ethanol-loaded rats.
Weight loss is common in patients with chronic obstructive pulmonary disease (COPD). Comprehensive nutritional assessment was conducted in two large groups of patients with COPD who were enrolled in the Respiratory Failure Research Program sponsored by the Japanese Ministry of Health and Welfare and the Kinki COPD Research Group. The incidences of mild malnutrition (%IBW < 90%) were 74% and 62%, respectively. The incidences of hypoalbuminemia were low: 10.0% and 6.5%, respectively. The incidence of imbalance in plasma amino acids, which was defined as an abnormally low BCAA/AAA ratio, was as high as 93% in patients with COPD and chronic respiratory failure. The %IBW was significantly related to the FEV1 and to the DLco/VA. The moderately-malnourished subpopulation was characterized by a greater degree of hyperinflation and hypercapnea: the measured resting energy expenditure (REE) was significantly higher than the values in age-matched healthy controls. REE/REEpred was significantly and inversely related to BCAA/AAA and to Pimax. REE was inversely related to FEV1%. REE in the subgroup with severe hyperinflation was significantly higher than REE in those with milder hyperinflation. Among patients with an FEV1% of less than 50%, mortality tended to be higher in those with lower body weight, and this relationship was stronger in patients with an FEV1% of more than 50%. When patients were given a BCAA-enriched enteral formula in addition to their usual diet for 3 months, there was a significant increase in body weight, transferrin level, and Pimax.
A recombinant Mycobacterium bovis bacillus Calmette-Guérin (BCG) vector-based vaccine that secretes the V3 principal neutralizing epitope of human immunodeficiency virus (HIV) could induce immune response to the epitope and prevent the viral infection. By using the Japanese consensus sequence of HIV-1, we successfully constructed chimeric protein secretion vectors by selecting an appropriate insertion site of a carrier protein and established the principal neutralizing determinant (PND)-peptide secretion system in BCG. The recombinant BCG (rBCG)-inoculated guinea pigs were initially screened by delayed-type hypersensitivity (DTH) skin reactions to the PND peptide, followed by passive transfer of the DTH by the systemic route. Further, immunization of mice with the rBCG resulted in induction of cytotoxic T lymphocytes. The guinea pig immune antisera showed elevated titers to the PND peptide and neutralized HIVMN, and administration of serum IgG from the vaccinated guinea pigs was effective in completely blocking the HIV infection in thymus/liver transplanted severe combined immunodeficiency (SCID)/hu or SCID/PBL mice. In addition, the immune serum IgG was shown to neutralize primary field isolates of HIV that match the neutralizing sequence motif by a peripheral blood mononuclear cell-based virus neutralization assay. The data support the idea that the antigen-secreting rBCG system can be used as a tool for development of HIV vaccines.
N-3554S, an optically active S-isomer of alpha-dihydrodecaprenyl phosphate, reduced the tumorigenicity of cultured B16-F10 mouse melanoma cells probably by affecting protein N-glycosylation. Accordingly, membrane glycoprotein samples were prepared from the melanoma cells cultured with or without N-3554S, and amounts and structures of N-linked sugar chains were determined. Analyses of the N-linked oligosaccharides released by hydrazinolysis from these samples and reduced with NaB3H4 revealed that the N-3554S-treated cells contain 1.5-1.8 times as much oligosaccharides as the control cells, and the relative amounts of high-mannose-type and bi-, tri- and tetra-antennary complex-type sugar chains are almost the same between two samples. Western blot analysis, however, showed that binding of L-PHA, which binds to oligosaccharides with the GlcNAc beta 1-->6(GlcNAc beta 1-->2)Man structure, is significantly reduced in 90 K, 96 K, 140 K, 155 K and 180 K glycoproteins in N-3554S-treated cells. Immunoblot analysis showed that the 140 K glycoprotein could be a fibronectin receptor. It was also shown that N-3554S treatment enhances the adhesiveness of the cells to fibronectin. These results indicate that N-3554S affects N-glycosylation of membrane glycoproteins and alters the cell surface properties of B16-F10 cells.