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Biomedical subjects

N Sakamoto

Publications and source records attributed to N Sakamoto.

At least 109 records · Page 6Linked to original sources
PubMed1998

Immune responses of adenoidal lymphocytes specific to Haemophilus influenzae in the nasopharynx.

OBJECTIVES: Investigate immune responses of adenoidal lymphocytes against outer-membrane protein P6 purified from nontypeable Haemophilus influenzae (HI). Clarify the role of adenoids in regulating the colonization of HI in the nasopharynx. STUDY DESIGN: Microbiological and immunological examinations of adenoids obtained from 21 children, 15 boys and five girls, from 1 to 13 years of age (median, 5 y), suffering from adenoidal hypertrophy complicated by otitis media with effusion (OME). METHODS: The incidence of HI in adenoids was compared with the number of P6-specific immunoglobulin (Ig) A-secreting cells in adenoids, determined by enzyme-linked immunoassay. RESULTS: Quantitative culture assay showed significant correlation between the numbers of HI in adenoids and those in nasopharyngeal secretions (NS). In children aged 5 years and younger, the numbers of P6-specific IgA-secreting cells in adenoids were significantly correlated with IgA antibody titers in NS (r = 0.68, P < .05). The numbers of P6-specific IgG- and IgA-secreting cells were lower in children aged 6 years and older than in children aged 5 years and younger. Furthermore, the number of P6-specific IgA-secreting cells was significantly increased in HI-negative subjects when compared with HI-positive subjects (P < .05). CONCLUSIONS: Adenoids play an important role as an effector site of the mucosal immune system in the upper respiratory tract. IgA immune responses in adenoids are responsible for the clearance of HI from the nasopharynx.

Adenoids↗
PubMed1998

Paradoxical pleural response to antituberculous chemotherapy and isoniazid-induced lupus. Review and report of two cases.

Among 28 inpatients receiving antituberculous chemotherapies including isoniazid (INH) and rifampicin, we found 2 patients with newly developing pleural effusion in the hemithorax during the initial phase of successful chemotherapy. The analysis of the effusion fluids revealed an elevated level of antinuclear antibody and a decreased level of total component, which are findings compatible with lupus pleuritis. The peripheral lymphocyte stimulation test using INH was positive in 1 patient. To the best of our knowledge, there has been no published discussion of the relationship between a paradoxical response to antituberculous treatment and INH-induced lupus.

Adolescent↗
PubMed1998

Anticoagulant and antiprotease activities of a heparinoid sulfated glucoside-bearing polymer.

We studied anticoagulant and antiprotease activities of the poly(glucosyloxyethyl methacrylate) sulfate [poly(GEMA)-sulfate] in plasma and purified enzyme systems in order to evaluate the anticoagulant behavior of a heparin-like sulfated glucoside-bearing polymer. As a result, we found that poly(GEMA)-sulfate can inhibit some coagulation proteases, although its antiprotease behavior differed from those of heparin and dextran sulfate. Poly(GEMA)-sulfate could not enhance antithrombin activity; therefore, we did not observe any significant inhibition of Factor Xa via antithrombin. However, we found that poly(GEMA)-sulfate was able to inhibit thrombin through the activation of heparin cofactor II. In addition, poly(GEMA)-sulfate was able to inhibit Tenase. In our previous research. we found that the anticoagulant activity of poly(GEMA)-sulfate is due primarily to the formation of an insoluble complex with fibrinogen. This paper showed that the antiprotease activities of poly(GEMA)-sulfate contribute to some extent to its anticoagulant activity.

Anticoagulants↗
PubMed1998

Comparison of diets among elderly female residents in two suburban districts in Chiang Mai Province, Thailand, in dry season--survey on high- and low-risk districts of lung cancer incidence.

By means of duplicate meals, we collected food samples of general female residents, aged 50 to 74 years at two suburban districts in Chiang Mai Province, which are distinguished by very high and low incidence rates of lung cancer. Then, on the basis of analyses of their consumption of foods by food groups, we compared their dietary habits in the dry season of northern Thailand with special reference to the difference in lung cancer incidence. In brief, the following features and difference in their dietary habits were found; 1) Rice, vegetables, and pork were most frequently eaten in both the districts. 2) Consumption of fruits, in both quantity and variety, at a high-risk district was much less than that at a low-risk district. 3) Female residents at a low-risk district consumed more variety of green and yellow vegetables than those at a high-risk district. 4). Potato was not found in food samples of a high-risk district. 5) confectionery was more prevalent in a low-risk district than at a high-risk district.

Aged↗
PubMed1998

[Clinical features and characteristics of paranasal sinus effusion in allergic sinusitis].

Plain paranasal sinus radiographs including occipitofrontal and occipitomental views often show abnormal shadows in patients with allergic rhinitis. For that reason, the relationship between chronic sinusitis and allergy has been discussed for many years. Type I allergy is thought to be involved in the sinusitis which is called allergic sinusitis. However, there is not enough information pertaining to this disorder. In order to determine the clinical feature and the characteristics of paranasal sinus effusion in allergic sinusitis, we investigated the differences between 20 patients with allergic sinusitis and 20 with non-allergic chronic sinusitis used as controls. Clinical symptoms (nasal discharge, nasal obstruction, headache, postnasal discharge) and anterior rhinoscopic findings (nasal discharge, nasal edema), clinical examinations (type of x ray maxillary sinus shadow, bacteriology of nasal discharge), and pathological features of the paranasal sinus effusion were examined and compared in the two kind of sinusitis. Pathological findings of the effusion sampled from 14 patients with allergic sinusitis and 15 with non-allergic sinusitis included the number of eosinophils, activated eosinophils and neutrophils, concentrations of interleukin (IL)-1 beta, IL-4, IL-5, IL-8, and concentrations of leukotriene C4/D4/E4 and prostaglandin E2. The incidence and degree of postnasal discharge as a symptom and a nasal finding were lower in allergic sinusitis patients than in the controls. Microorganisms were detected less frequently in the allergic group. The number of eosinophils, activated eosinophils and neutrophils was higher in the paranasal sinus effusion of the patients with allergic sinusitis. The concentrations (ng/mg of protein) of IL-1 beta and IL-8 showed no difference between the two groups, but IL-4, and IL-5 were more prevalent per mg of protein in the effusion of allergic sinusitis patients. These findings suggest that the clinical features of allergic sinusitis include a low incidence and degree of postnasal discharge and a low rate of detection of bacteria, and that the sinus effusion is characterized by the presence of more eosinophils, activated eosinophils, and IL-5 than in those of chronic sinusitis.

Adolescent↗
PubMed1998

[Reproducibility and validity of a semi-quantitative food frequency questionnaire].

The reproducibility and relative validity of a semi-quantitative food frequency questionnaire (FFQ) were evaluated. Subjects were 72 (36 men and 36 women) residents of N island, Shimane Prefecture in Japan, aged 50-76 years. The questionnaire was administered twice at an interval of one week (FFQ1, FFQ2), and 7-day weighing diet records were collected during that period. This protocol was conducted in summer and winter. The mean intakes for 11 nutrients calculated from the FFQ1 and FFQ2 were similar and, those from the FFQ1 were smaller than those from the diet records for all but fat and vitamin C. Pearson correlation coefficients assessing reproducibility between nutrient intakes from FFQ1 and FFQ2 ranged from 0.59 for vitamin C to 0.90 for carbohydrate. Validity was measured by comparing nutrient intakes from FFQ1 with those from the 7-day diet record, and Pearson correlation coefficients ranged from 0.15 for iron to more than 0.35 for total energy and macronutrients. These correlation coefficients showed slight difference by gender or age group, but did not vary materially between seasons. These data indicate that this questionnaire is reproducible but has some problems in validity.

Aged↗
PubMed1998

A practical object-oriented approach to a development of a next generation hospital information system.

KIND (stands for Kyushu university hospital Information Network Database) is a five years project, which aims to provide integrated services for patients, physicians, researchers and other hospital staffs. The final product of KIND is a next generation hospital information system. A physicians' clinical workstation, for example, integrated into a secured medical information network, can electronically develop a longitudinal medical record and interface with pharmacies, laboratories, medical specialists, and radiologists, as well as develop patient census and demographic profiles, in addition to doing electronic claims. Since clinical requirements on those medical records may vary for each case, we would like to have an essential data model under the hood. We decided to introduce domain analysis method to produce a relevant domain model. A domain analysis method captures the nature of business and helps us have an essential and extensible data model. Although there are several ways to describe a domain model, we chose an object-oriented description and consequently implementation using an object-oriented database system. Once we could have a decent domain model and implemented it as an object-oriented data model, application programs can utilize those data very easy without worrying extra efforts like finding complex queries including multiple joins. More over, if an application uses decent object-oriented technologies, it allows a user to access whole aspects of data transparently. This paper describes the architecture of KIND (the system) and outlines our domain model. In this paper, we also describe a practical application of several object-oriented technologies to develop a next generation hospital information system.

Database Management Systems↗
PubMed1998

[Immunohistochemical study on pulmonary neuroendocrine cells containing calcitonin gene-related peptide in sudden infant death syndrome].

To examine whether pulmonary neuroendocrine cells (PNEC) is associated with sudden infant death syndrome (SIDS), distribution and function of PNEC were investigated in infants from one to twelve months of age, including 19 cases with SIDS and 18 control cases without congenital heart disease and premature birth. In this study, lung tissue sections were immunostained with antibodies against chromogranin A (CGA) and calcitonin gene-related peptide (CGRP). Although the positivity of CGA in SIDS cases was not significantly different from that in control, the positivity of CGRP in SIDS cases was lower than that in control cases among one to four months old (p < 0.05). Our results suggest that respiratory and/or circulatory regulation of cases with SIDS is disturbed by reduction of CGRP expression, because CGRP is well known to be a vasodilator, a neurotransmitter and a promoter for proliferation of epithelium in airways.

Calcitonin Gene-Related Peptide↗
PubMed1998

[A guide for the timing of peripheral blood stem cell harvest in patients with lung cancer].

Harvest of peripheral blood stem cells (PBSC) was performed 57 times in 17 lung cancer patients after standard-dose chemotherapy (cisplatin, etoposide) supplemented with granulocyte-colony stimulating factor (G-CSF). In every case, more than 1.5 x 10(6)/kg CD 34+ cells were collected by 2-5 apheresis. Statistical significance was noted between peripheral leukocyte counts (WBC) and collected CD 34+ cell counts (p = 0.0298), between peripheral platelet counts and collected CD 34+ cell counts (p = 0.0009), and between the peripheral immature granulocyte ratio and collected CD 34+ cell counts (p < 0.0001). Because of the remarkable relationship between collected CD 34+ cell counts and peripheral WBC counts, peripheral platelet counts and the peripheral immature granulocyte ratio, these parameters were useful for determining the correct timing of PBSC harvest.

Adult↗
PubMed1998

Differential expression of sea urchin Otx isoform (hpOtxE and HpOtxL) mRNAs during early development.

Two distinct types of orthodenticle-related proteins (early type: HpOtxE, late type: HpOtxL) of the sea urchin, Hemicentrotus pulcherrimus, have been implicated as enhancer element binding factors of the aboral ectoderm-specific arylsulfatase (HpArs) gene. In order to understand the role of these isoforms during sea urchin development, we have isolated and characterized HpOtx gene. Here we describe the spatial expression patterns of HpOtxE and HpOtxL mRNAs and effects of overexpression of these mRNAs on embryogenesis. Whole-mount in situ hybridization using each isoform-specific probe reveals the complex and dynamic change of expression patterns among three germ layers. HpOtxE mRNA is maternally stored and exists apparently in a nonlocalized manner by the blastula stage. After hatching, HpOtxE transcripts are expressed predominantly in presumptive endoderm cells and gradually decrease during gastrulation. Signals for HpOtxL mRNA are intense at the vegetal half after hatching and subsequently, its expression is restricted to the micromere-derived cells. After primary mesenchyme cell (PMC) ingression, HpOtxL transcripts are localized at the vegetal plate and thereafter, concentrated primarily in ectoderm. Eggs injected with HpOtxE or HpOtxL mRNA develop into similar radialized structures without PMC ingression and gut invagination, whose oral-aboral axes are disrupted. Overexpression of HpOtxE induces accumulation of HpOtxL mRNA at the significantly earlier stages, though HpOtxL overexpression inhibits the accumulation of HpOtxE transcripts. Expression patterns of HpOtxE and HpOtxL in all three germ layers and dramatic morphological changes observed in the mRNA-injected embryos suggest that each HpOtx isoform has an important role in sea urchin embryogenesis.

Animals↗
PubMed1998

[Antitumor effect of human lactoferrin against newly established human pancreatic cancer cell line SPA].

This paper describes the antitumor effect of human lactoferrin against the human pancreatic cancer cell line SPA, which was newly established in our laboratory from a metastatic liver tumor of pancreatic origin. In tissue culture, the cancer cells proliferated rapidly at 16 hours of doubling time, and produced tumor markers into the culture medium at a high concentration. Subcutaneous and intraperitoneal transplantation of these neoplastic cells into nude mice resulted in tumor formation and carcinomatous peritonitis. The inhibitory effect of human lactoferrin on the cell growth of SPA was found both in vivo and in vitro. There was significant inhibition of cell growth in vivo at the concentration of 1 microgram/ml of hLf in the culture medium. And in the in vivo assay, hLf delayed the growth of subcutaneously transplanted tumors into BALB/c nude mice, and the effect was retained for two weeks. These results indicate the possibility that hLf will become one of the new drugs for adjuvant therapy against pancreatic cancer.

Animals↗
PubMed1998

[A case of spastic paraparesis with mental deterioration and markedly thin corpus callosum--callosal dysfunction demonstrated by magnetic stimulation].

We have studied function of the corpus callosum in a patient with spastic paraparesis with mental deterioration and markedly thin corpus callosum using magnetic stimulation methods. In a 21-year-old woman with slowly progressive gait disturbance, neurological examination showed mental deterioration, euphoria, spastic paraparesis, bilateral Babinski's sign, and hyperesthesia caudal to the eighth thoracic level. No abnormalities were observed in electroencephalograms. Magnetic resonance imaging (MRI) studies of the brain showed cerebral cortical atrophy, markedly thin corpus callosum, and dilated cavum septum pellucidum and cavum Vergae, but spinal cord MRIs showed no abnormalities. The lysosomal enzyme activities, whose reduction was known to cause leukodystrophy, were all normal. Very long chain fatty acid was not increased in her blood, which is against adrenoleukodystrophy. She had no anti-HTLV-1 virus antibody. Based on these clinical features and the results of biochemical analyses, we diagnosed this patient as having spastic paraplegia associated with hypoplasia of the corpus callosum (Nojima and Iwabuchi). We performed three studies on the central motor pathways in this patient. The latencies of responses recorded from upper or lower limb muscles were all within the normal range, despite that the thresholds were slightly increased. This suggests that axonal degeneration occurs in the central motor pathways, which is consistent with the autopsy findings of a patient with hereditary spastic paraplegia associated with hypoplasia of the corpus callosum. Connection between the bilateral motor cortices was investigated by magnetic stimulation of both motor cortices. The suppression of the motor cortex evoked by stimulation of the contralateral motor cortex through the corpus callosum was absent in this patient. Intracortical inhibition within the motor cortex was demonstrated to be normal by a paired-magnetic stimulation technique. Based on the results of these results of these two experiments, we conclude that the function of the corpus callosum was disturbed in the present patient. This report first shows the functional abnormality of the extremely thin corpus callosum in a patient with hereditary spastic paraplegia associated with hypoplasia of the corpus callosum.

Adult↗
PubMed1998

Mineral concentrations in the blood of male smokers and non-smoking males and females measured with fluoro-X-ray analyzer.

For clarification of the effects of smoking on mineral absorption in red blood cells (RBC) and serum, their concentrations at these sites were examined in ten male smokers and 12 male and 10 female non-smokers by fluoro-X-ray analysis. K in serum was high, and P, Ca and Fe low, compared to RBC. Mg and S in serum and RBC were essentially the same. S, Mg, P and K in RBC of smokers were higher than in male non-smokers, and Ca was lower. S and Ca in serum of smokers were significantly lower than in male non-smokers. P in smokers was higher than in non-smokers. P in RBC may possibly activate the reflux of Mg into RBC and may suppress that of Ca. In smokers, the correlation coefficient (gamma) between Fe and Ca was r = -0.68 in RBC, and r = 0.76 in serum. Also gamma between P and Mg was r = 0.4 in RBC and r = -0.48 in serum. Thus Fe in RBC may suppress the reflux of Ca. Mg and Ca in serum of females were significantly higher than in male non-smokers. Ca in RBC of females was significantly higher than in male non-smokers, and P, K and Fe were significantly lower. The product of Ca and P in RBC of females was lower than in male non-smokers, while in serum it was higher. gamma between P and Ca, and between Fe and Ca in RBC of females were negative, while they were positive in male non-smokers. The correlations in female RBC had the same pattern as in male smokers.

Adult↗
PubMed1997

Immunohistochemical detection of human milk components aspirated in lungs of an infant.

We examined an autopsy case of an infant whose cause of death was suspected to be asphyxia due to human breast milk aspiration. In order to demonstrate aspirated milk in the lungs, we conducted immunohistochemical staining using eight antibodies against the components of human milk. Seven of the eight antibodies reacted positively with the substances suspected to be aspirated milk. We concluded that immunohistochemical staining with these antibodies is useful to demonstrate human milk aspiration and provide some keys for detecting the causes of unexpected infant deaths.

Autopsy↗
PubMed1997

Effect of an aldose reductase inhibitor on abnormalities of electroretinogram and vascular factors in diabetic rats.

The effect of an aldose reductase inhibitor, [5-(3-thienyl) tetrazol-1-yl] acetic acid (TAT), on the electroretinogram was determined in rats with streptozotocin-induced diabetes. Laboratory chow containing 0.05% TAT was given to rats for 2 months, while other diabetic rats were untreated. Groups of TAT-treated and untreated normal rats were also studied. Treatment with TAT produced significant improvement of the electroretinogram. TAT shortened the peak latencies of the b-wave oscillatory potentials, which were significantly prolonged in untreated diabetic rats (P < 0.0001 vs. untreated normal rats). This was accompanied by a significant decrease in the retinal sorbitol and fructose concentrations (by 46.5% and 25.7%, respectively). TAT treatment of diabetic rats also markedly reduced ADP-induced platelet aggregation and significantly increased the red blood cell 2,3-diphosphoglycerate level, accompanied by a marked reduction in sorbitol and fructose concentrations of platelet and red blood cells. There were significant correlations between the summed b-wave peak latencies and platelet aggregation or the 2,3-diphosphoglycerate level in diabetic rats. These findings suggest that an aldose reductase inhibitor, TAT, has therapeutic value for diabetic retinopathy.

2,3-Diphosphoglycerate↗
PubMed1997

Two isoforms of orthodenticle-related proteins (HpOtx) bind to the enhancer element of sea urchin arylsulfatase gene.

The sea urchin (Hemicentrotus pulcherrimus) arylsulfatase (HpArs) gene, expressed specifically in aboral ectoderm, contains a 229-bp enhancer in its first intron that is required for the activation of HpArs gene expression. Deletion analysis shows that a tandem repeat of orthodenticle-related protein (Otx) binding sites are responsible for the activity of this enhancer. Gel mobility shift analysis reveals that three types of Otx-proteins, which show different mobilities in gel shift assays, form complexes with the enhancer. Band I appears before hatching and gradually decreases by the gastrula stage. Band III appears at the blastula stage and Band II appears at the mesenchyme blastula stage; the levels of Band II and III remain constant until the gastrula stage. Two distinct types of HpOtx cDNA clones have been isolated from cDNA libraries of unfertilized eggs and gastrulae. Nucleotide sequences of the homeobox and downstream regions are well conserved in the two types of HpOtx cDNAs, while the region upstream from the homeobox has different nucleotide sequences. By genomic Southern blot analysis, only a single copy of HpOtx gene is detectable in the Hp genome, making it likely that two HpOtx isoforms are generated from the same gene. Results from Northern blot analysis confirm the presence of two types of HpOtx transcripts. Transcriptional regulation of the HpArs gene may, in part, be carried out through switching of Otx isoforms.

Amino Acid Sequence↗
PubMed1997

A novel function of transferrin as a constituent of macromolecular activators of phagocytosis from platelets and their precursors.

Macromolecular activators of phagocytosis from platelets (MAPP:s-MAPP, 1500kDa and 1-MAPP, 300kDa) are glycoproteins released from human platelets and activate leukocyte phagocytosis via the Fc gamma receptors. Their production can be shown in CPD-stored platelets which have lost MAPP releasing activity by incubation with plasma-derived precursos of MAPP (pre-MAPP : pre-s-MAPP, 150kDa and pre-l-MAPP, 300kDa) in the presence of Ca++. Partial amino acid sequence analysis of s-MAPP revealed that it had homogeneity with transferrin (TF). Affinity chromatography using anti TF immunosorbent column showed that all of pre-MAPP and MAPP had immunoreactivity with anti TF antibodies. S-MAPP and 1-MAPP rich preparations from platelet release products lost their activity after treatment with ATP at acidic pH, in which condition iron atoms could be removed from holo-transferrin molecules. In the experiment using polymerized TF and stored platelets, it was shown that platelets incubated with dimer and tetramer TF could produce MAPP function. These results suggest that dimer and tetramer transferrin are precursors of s-MAPP and 1-MAPP, respectively and that iron atoms are necessary for their phagocytosis activating function.

Amino Acid Sequence↗