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Biomedical subjects

N Yamaguchi

Publications and source records attributed to N Yamaguchi.

At least 541 records · Page 30Linked to original sources
PubMed1991

Double aortic arch associated with coarctation of both limbs: a case report.

A case of double aortic arch with coarctation of both limbs is described. The patient, a thirteen-year-old girl, demonstrated only the symptoms of coarctation and had no intracardiac anomalies. Discrete coarctation of bilateral limbs distal to the subclavian artery was shown by aortography. Although either double aortic arch or coarctation of the aorta is not so rare, the combination of these two anomalies is quite unusual. This is the third case in the world literature.

Abnormalities, Multiple↗
PubMed1991

Interpersonal awareness and smoking behavior in the workplace.

A questionnaire survey was conducted in small-scale production companies in Japan to examine "interpersonal awareness" and smoking behavior in the workplace. Interpersonal awareness (IA) of smokers is defined as awareness of other people's presence when smoking. Study participants were 1048 smokers and 744 nonsmokers, contrasted by worksite: office or production. Controlling for selected baseline variables, office work smokers, who smoked more in the workplace than production work smokers (77.4% vs 51.6%, p < .001), had a higher IA in the workplace (75.5% vs 58.9%, p < .001) but did not differ in IA at home (69.7% vs 66.0%). In male smokers of both worksites, degree of IA in the workplace correlated positively with that at home (rs = .36, p < .001, office; rs = .45, p < .001, production), and daily cigarette consumption correlated negatively with degree of IA at home (rs = -.44, p < .001, office; rs = -.17, p < .001, production). A predilection for smoking more at home than in the workplace correlated with higher IA in the workplace for male office smokers (rs = -.21, p < .01). In contrast, a predilection for smoking more at home than in the workplace correlated with lower degree of IA at home for production smokers of both sexes (rs = 20, p < .001, male; rs = .53, p < .05, female). Interpersonal awareness is deemed an important behavioral factor for smoking workers.

Adult↗
PubMed1991

A histological and flow cytometric study of dog brain endothelial cell injuries in delayed radiation necrosis.

The pathogenesis of delayed cerebral radiation necrosis was studied histologically and biochemically in 25 dogs with special attention to vascular endothelial cell injuries. The dogs were sacrificed 3 to 30 months after irradiation with a single dose of 15 Gy to the head. Brain specimens were appropriately fixed for light and electron microscopic studies, and capillary endothelial cells were isolated for flow cytometric study. The endothelial cells were stained with acridine orange, then the cell ratios in the reproductive phase (S + G2 + M) were investigated with flow cytometry. Thereafter, Feulgen hydrolysis and computer analysis of the hydrolysis curves were performed to examine the qualitative changes in deoxyribonucleic acid (DNA) of endothelial cells after irradiation. Under light microscopy, spongy degeneration with small cell infiltration was observed, especially in the frontal white matter, at 6 months after irradiation. At 9 months, necrotic foci appeared and developed until 15 months after irradiation. Blood vessels around the necrotic area showed luminal narrowing with endothelial hyperplasia and proliferation. At 30 months, no fresh necrotic lesions were observed. Under electron microscopy, endothelial cells of capillaries and small vessels around the necrotic area showed an increase of pinocytosis, and in the nuclei there was an increase of infoldings and euchromatin. The cell ratios in the reproductive phase were 14.5% to 23.3% (maximum at 9 months) in the irradiated group compared to 6.4% in the control group. The rate constant of apurinic acid production, a parameter correlating with DNA transcriptional activity, was minimum at 3 months and maximum at 9 months after irradiation. The data suggest that impairment of the microcirculation plays an important role in the pathogenesis of delayed radiation necrosis, and that the time of necrosis occurrence closely correlates with the cell cycle of vascular endothelial cells.

Animals↗
PubMed1991

[The absence of monocyte-granulocyte antigen expression in a case of AML].

The brief record of a 25 y. o. male patient with AML (FAB M1) is shown, in whom the blast cells did not express any of the 5 myeloid antigens or the other-lineage related antigens, as detected with the monoclonal antibodies. The blast cells were induced to express CD13 antigen after a short-term culture in vitro. This result suggests that CD13 antigen can be expressed virtually by all AML cells, since CD13 antigen is known to cover fresh AML cells at the highest incidence. No unusual clinical feature was noted in this patient as AML case. The collected documentation of antigen-free AML cases seems necessary for the relevant understanding of AML heterogeneity.

Adult↗
PubMed1991

Cloning of alpha 1(IV) and alpha 2(IV) collagen cDNAs from rabbit corneal endothelial cell RNA.

To understand the role of type IV collagen in embryogenesis, regeneration, and tissue repair of the cornea at the molecular level, the authors isolated clones coding for rabbit alpha 1(IV) and alpha 2(IV) chains from a cDNA library constructed with rabbit corneal endothelial cell RNA. The isolated alpha 2(IV) cDNA clones encode a part of a 5' untranslated region, the signal peptide, the 7S domain, part of the triple-helical domain, and the entire carboxyl-terminal nontriple-helical (NC1) domain. By cross hybridization, using one of the alpha 2(IV) cDNA inserts, a cDNA clone encoding the alpha 1(IV) chain was isolated from a lambda gt10 library primed with oligo(dT). The clone covered a short portion of the triple-helical domain, the entire NC1 domain, and a short 3' untranslated region. The nucleotide-sequence analysis of these clones provides, for the first time to the authors' knowledge, the primary structure of the carboxyl-terminal portion of both rabbit alpha 1(IV) and alpha 2(IV) collagen chains. Between the alpha 1(IV)NC1 and the alpha 2(IV)NC1, 61% and 66% sequence similarities were observed at the amino acid and nucleotide levels, respectively. The locations of all the 12 cysteinyl residues were conserved in the two NC1 sequences.

Amino Acid Sequence↗
PubMed1991

[Expression and detection of platelet specific genes in human megakaryocytic cells].

The expression and biological function of interleukin-6(IL-6), and its receptor mRNA, were studied in a human megakaryocytic cell line (CMK). IL-6 possessed stimulatory effects on the DNA synthesis as well as colony formation of CMK cells. The IL-6 receptor mRNA could be detected by the method of reverse transcriptase polymerase chain reaction (RT-PCR) but not Northern blotting. On the contrary, IL-6 mRNA was detected by the method of RT-PCR, and its expression induced by the addition of 12-O-tetradecanoylphorbol-13-acetate (TPA) could be clearly shown by Northern blotting. These findings indicate that IL-6 and its receptor mRNA should be analyzed by both methods, and the growth and differentiation of CMK cells may be controlled by an IL-6 autocrine loop. Next, the expression and biological role of low molecular GTP-binding proteins (smg p21A and -B) mRNAs were examined in CMK cells. Both the smg p21A and -B mRNAs were detected in CMK cells using Northern blotting, and their levels were markedly elevated by TPA treatment. The mRNA level of glycoprotein IIb, a typical marker of the megakaryocytes, was increased by TPA, but the time course of the increase in the smg p21 mRNA levels was more rapid that that in the GPIIb mRNA level. These findings suggest that smg p21s play an important role during the TPA-induced differentiation of CMK cells.

Blood Platelets↗
PubMed1991

Influence of subepithelial deposits on permeability of the glomerular capillary wall in serum sickness nephritis in the rat.

Serum sickness nephritis was induced in male Fisher rats by immunization with egg albumin (EA). Correlations of subepithelial deposits (SD) with size and charge barriers of the glomerular filter were investigated using native (NF) and cationized (CF) ferritin as tracer probes. In proteinuric animals large numbers of NF molecules perfused from the abdominal aorta were observed to cross the glomerular basement membrane (GBM) and enter SD. The concentration of NF molecules was higher in GBM segments with SD than in GBM segments without SD, and the concentration of these molecules was higher within SD than in the intervening GBM. In contrast, CF clusters were fewer in number in the lamina rara externa (LRE) of GBM segments with SD than in the GBM segments without SD. CF particles could not be observed within SD, even in the areas of podocyte detachment. It is suggested that permeability in GBM segments with SD increases and that the development of proteinuria in this model can be attributed to alterations in both charge- and size-selective barriers to glomerular filtration.

Animals↗
PubMed1991

[Studies of novel bioactive substances in the spent media of cell lines using protein-free culture system].

Many human cell lines have been maintained in fetal bovine serum (FBS)-supplemented medium. These produce and secrete many substances such as transferrin, alpha 1-antitrypsin, alpha 2-macroglobulin, alkaline phosphatase, gamma-glutamyltranspeptidase, creatine kinase, carcino-embryonic antigen, alpha-fetoprotein, and cytokines including colony stimulating factors and transforming growth factors and further they may produce small amounts of unknown substances. Usually, small amounts of substances have to be concentrated as highly as possible for detection, but FBS interferes with procedures. A protein-free culture system in an ideal method for detecting small quantities of substances which originate from cell lines without interference by FBS. Our protein-free culture system can be available in every laboratory since this is not only an economical method, but also an effective method for the saving of purification procedures. Moreover, this is a most suitable method for surveying unknown substances derived from cell lines.

Biological Factors↗
PubMed1991

[Protein-free culture of esophageal cancer cell lines].

We have established 13 esophageal cancer cell lines capable of growing in a protein-free environment. The growth of these cells was not affected by conditioned medium, but the growth of NIH3T3 cells and human fibroblasts was stimulated by conditioned medium. On the other hand, conditioned medium inhibited the growth of human endothelial cells. Amplified int-2 oncogene correlated well with the growth of cells in a protein-free environment but the number of EGF receptors and growth effect of EGF did not relate to such growth. Esophageal cancer cells grow automatically, possibly involving mesenchymal cells via the paracrine system. This results in a poor prognosis in patients.

Cell Division↗
PubMed1991

[Salivary epidermal growth factor in patients with peptic ulcer].

Recent animal studies suggest salivary epidermal growth factor (EGF) has a cytoprotective effect in the upper GI tract and is one of the important factors to promote the healing of experimental ulcer. The present study was undertaken to clarify the role of salivary EGF in peptic ulcer patients. Saliva samples were collected from 129 endoscopically normal subjects and 232 peptic ulcer patients. Salivary EGF concentration was measured by RIA. Salivary EGF output in normal subjects was 5.26 +/- 0.26 (ng/5 min) (mean +/- SE). Those in patients with gastric ulcer (GU), duodenal ulcer (DU) and gastroduodenal ulcer (GDU) were 10.74 +/- 0.15, 8.13 +/- 0.83 and 9.79 +/- 0.91. EGF output in GU and GDU patients were higher than that in normal subjects respectively. Tractable GU patients (healed within 3 months with regular regimen) had higher EGF output than intractable GU patients. Among tractable GU patients, those who had healing within 8 weeks had higher output. EGF output in patients with recurrent GU was lower than that in non-recurrent GU patients. In 10 GU patients, EGF output became higher in healing stage than in active stage. Salivary EGF may promote the healing and prevent the recurrence of human gastric ulcer.

Adult↗
PubMed1991

[An evaluation of combination antibiotic therapy in infections with hematological disorders. Hyogo Cooperative Study Group of Infectious Diseases Complicating Hematological Disorders].

A clinical study was undertaken to determine the effects of combination antibiotic therapy in 104 patients with infections associated with hematological disorders. All patients were treated with sulbactam/cefoperazone (SBT/CPZ) plus an aminoglycoside as an empiric therapy for fever. The overall efficacy rate of the therapy was 63.5%. Efficacy rates were 61.2% and 71.9% when initial neutrophil counts were less than 500/mm3 and over 500/mm3, respectively. No significant difference was found between the cases in which initially used antibiotics were continued (efficacy rate 62.5%) and those in which antibiotics were switched during the course of therapy (65.6%). Antibiotic therapy with SBT/CPZ plus an aminoglycoside provides adequate antibiotic coverage against infections associated with hematological disorders. This combination was highly effective even in the neutropenic periods of febrile patients.

Adult↗
PubMed1991

[Laboratory evaluation of the Sysmex NE-7000 flagging system; a tool for the recognition of abnormal cells in white cell differentials].

Sysmex NE-7000 flagging system was evaluated for the recognition of abnormal cells in white cell differentials. Six flags that could mark blasts, immature granulocytes, left shift, nucleated red blood cells, atypical lymphocytes, and platelet clumps were selected for evaluation. 182 morphologic abnormal samples were screened from the Kobe University Hospital patients, by means of the 600 eye counts differentials. Blasts flag missed 8 of 28 cases, and immature granulocytes flag missed 25 of 56 cases. These missed cases contained either relatively few abnormal cells; less than 3% immature granulocytes, or absolutely few cells; less than 201 per micro liter blasts. Platelet clumps flag missed only 2 of 23 cases. But nucleated red blood cells and atypical lymphocytes flags missed all of 7 and 4 cases respectively. Left shift flag missed 36 of 64 cases, but it could help marking immature granulocytes or blasts. To use the NE-7000 as a screening tool, we compared the NE's all 35 flags versus abnormal cells or status based on the 100 eye counts. 1,153 cases were analyzed. Full agreement; 1047 (90.8%), partial agreement; 61 (5.2%), distributional false normal; 7 (1.6%), and morphological false normal; 4 (4.6%), were obtained. The more flags were used, the less abnormal cases were missed. But it accompanied the increase of the flag positive cases that must be confirmed by eye.

Blood Platelets↗
PubMed1991

Platelet factor 4 gene expression in a human megakaryocytic leukemia cell line (CMK) and its differentiated subclone (CMK11-5).

The human cell line CMK spontaneously expresses megakaryocytic characteristics and can be induced to differentiate into mature megakaryocytes after exposure to 12-O-tetradecanoylphorbol-13-acetate (TPA). In comparison with CMK, we have examined the characteristics of a subclone, designated as CMK11-5, that is morphologically larger than the parent clone CMK and contains multinucleated giant cells. All CMK11-5 cells were positive for platelet peroxidase (PPO) activity, and some contained abundant alpha-granules and well-developed demarcation membranes. CMK cells had few demarcation membranes and alpha-granules, and 10% of these cells were found not to possess PPO activity. Phenotypic analysis revealed the percentage of CMK11-5 cells for platelet glycoprotein (GP) IIb/IIIa (CD41a), and GPIIIa (CD61) was greater than that for CMK cells. On the basis of these findings, CMK11-5 cells were considered to be more differentiated than CMK cells. We further examined the expression of GPIIb and platelet factor 4 (PF4) mRNA by Northern blot hybridization using 32P-labeled cDNA probes for GPIIb and PF4 in CMK and CMK11-5 cells. CMK cells exhibited mRNA for GPIIb, and its expression was augmented by TPA addition, but not PF4. In contrast, CMK11-5 cells were found to contain mRNA for GPIIb and PF4, and their mRNA levels were increased by the addition of TPA. The immunoreactive PF4 antigen was not detected in the TPA-treated CMK11-5 cells or in the culture medium of these cells. These results indicate that expression of mRNA for PF4 is a useful marker for the identification of mature megakaryocytes. Detection of mRNA for PF4 is a more sensitive method for characterization of megakaryocytic cells than that for the PF4 antigen.

Blotting, Northern↗
PubMed1991

[EEG data filing system with personal computer and magneto-optical disc].

We established a new computerized EEG filing system, in which an EEG machine was connected to an EEG filing unit which consisted of a personal computer with a 32 bit CPU, 18 channel analog -to-digital and digital-to-analog converters, and a magneto-optical disc driver. This system has the following merits. The system was space-saving, the space required to store the EEG data, being only 1/500 of that required for storing EEG record. Though the system had two independent EEG filing units, our original file configuration enabled us to have access to all of the recorded EEG data anytime for more than 10 years. The system enabled us to display EEG data continuously on the high resolution CRT, just as if turning the page of an EEG record paper, and through the quick scanning, enabled us to view the entire EEG pattern. Furthermore, the system enabled us to conduct reliable digital analysis for EEG data by entering the EEG data without artifacts into a data processor after confirmation on the display. In the system, we used data files with the MS-DOS operating system. This enabled us to analyze the data obtained by a personal computer operating on other systems, by transferring the data to a floppy disc operating on our system. Our EEG filing system allows quick access to data as well as mass data storage.

Electroencephalography↗
PubMed1991

[Evaluation of brain perfusion SPECT imaging using 99mTc-ECD].

Fundamental and clinical evaluation was performed on 99mTc-ECD, a new agent for brain perfusion SPECT. Radiochemical purity reaches a plateau of approximately 98% at 30 min after reconstitution and remains stable up to 24 hours later. A biodistribution study showed approximately 5% injected dose in the brain, very slow brain washout of 5.6% per hour on the average, and rapid washout from the other organ mainly through the urinary system. Brain ECD distribution was determined within 2 min postinjection and remained stable for up to 1 hour. Three hours later, slight but significant changes in brain distribution were observed, that were relative reduction of cerebral cortical activity and gray to white matter activity ratio, and relative elevation of white matter and thalamic activities. Comparative studies of ECD images with IMP and HMPAO images revealed that radioactivity contrast between affected and unaffected areas was less prominent in ECD than in IMP in cerebral and cerebellar cortical lesions, more prominent in ECD than in IMP in striatal and thalamic lesions, and somewhat more prominent in ECD than in HMPAO in both lesions. Imaging around 1 hour postinjection seems to be more appropriate than immediate postinjection imaging because of the clearance of the extracranial radioactivity and somewhat better radioactivity contrast between affected and unaffected areas.

Adult↗