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Biomedical subjects

N Yamaguchi

Publications and source records attributed to N Yamaguchi.

At least 487 records · Page 27Linked to original sources

[Pulmonary arteriography and bronchial arteriography in pulmonary embolism].

Pulmonary arteriography is the most reliable technique for evaluation of pulmonary embolism and other vascular abnormalities. A definitive diagnosis of pulmonary embolism is made on the basis of direct angiographic signs of emboli of intravascular filling defect and vessel cut-off sign. To obtain these findings, pulmonary arteriography needs to be performed as soon as possible, and in acutely ill patients who are in shock and under consideration for thrombolytic therapy or emergency embolectomy, the study should be performed on an emergency basis. Digital subtraction pulmonary angiography may be an useful technique for massive pulmonary embolism, but it cannot exclude clinically important peripheral pulmonary embolism. Wedged pulmonary arteriography can demonstrate the direct signs of distal emboli, which are difficult to obtain by main pulmonary artery injection angiogram. In the chronic stage of pulmonary embolism, bronchial arteriogram shows collaterals to pulmonary arteries. This study may be useful in patients with chronic pulmonary embolism, especially when thromboembolectomy is planned.

Angiography, Digital Subtraction↗

Detection of Epstein-Barr virus genome in natural-killer-like cell line, YT.

YT cells, originally reported as a natural-killer-like (NK-like) lymphoid cell line, were investigated for Epstein-Barr virus (EBV) genome, gene rearrangement for T-cell receptor (TCR), phenotype and function. The YT cells of the original batch (YT-0) and two subclones (YT2C2 and YTC3) expressed EBV-associated nuclear antigen, and the BamHI-digested DNA showed the 3.4 kb hybridizing band with the BamHIW probe of EBV DNA in Southern blot analysis. When tested with latent-infection membrane protein probe, an identical hybridizing band was shared, indicating that all three sources of YT cells were of monoclonal derivation in terms of the terminal repeat junctional structure of EBV DNA, and that the original YT cells had been infected with EBV before the isolation of the two subclones. The cell-surface antigen analysis revealed the expression of CD7, CD28, CD30, CD45R0, TLiSA and S6F1 antigen besides the originally recorded CD25, CD56 and HLA-DR antigen. Gene rearrangement analysis showed the germ-line genotype, including TCR gamma and delta as well as beta chain. The Northern blot study using the CD3 epsilon and CD3 delta chain gene probes revealed CD3 epsilon, but not CD3 delta RNA. The YT-0 cells exhibited NK and antibody-dependent cellular cytotoxicity activity, but the YT2C2 and YTC3 cells did not. It was not resolved whether the fresh neoplastic NK-like cells of the YT-cell donor carry EBV genome, but YT cells, the first lymphoid cell line found to have EBV genome and non-B lymphoid properties, are valuable for investigating the relationship between EBV and human non-B lymphoid hematopoietic cells.

Antigens, Surface↗

Alterations in circulating levels and cardiovascular tissue content of neuropeptide Y-like immunoreactivity during the development of deoxycorticosterone acetate-salt hypertension in the rat.

OBJECTIVE: To investigate the modification of plasma and tissue neuropeptide Y-like immunoreactivity (NPY-li) concentrations, in relation to blood pressure and plasma catecholamine levels, during the development of deoxycorticosterone acetate (DOCA)-salt hypertension. METHODS: Mean arterial pressure (MAP), heart rate, tissue and plasma NPY-li levels, and aortic norepinephrine and epinephrine plasma levels were measured in conscious DOCA-salt hypertensive rats treated for 1, 2 and 3 weeks, and in their respective normotensive controls. RESULTS: Both norepinephrine and NPY-li plasma levels increased significantly in parallel with blood pressure during DOCA-salt treatment, so that MAP was significantly correlated with plasma norepinephrine and NPY-li levels in hypertensive rats. Plasma NPY-li levels were also correlated with norepinephrine levels only in hypertensive rats, but were correlated with epinephrine levels only in normotensive animals. Tissue NPY-li content was lower in the mesenteric artery and heart ventricles after 1-3 weeks of DOCA-salt treatment, but the content in the adrenal gland was not significantly different from that in normotensive rats. CONCLUSIONS: In DOCA-salt hypertensive rats, increased plasma NPY-li levels originate primarily from the sympathetic nerves, since those levels were correlated exclusively with circulating norepinephrine levels and they were associated with a reduction in NPY-li content of the heart and mesenteric artery. It is thus possible that the enhanced release of NPY-li from sympathetic nerves could contribute to the rise in blood pressure and to the maintenance of hypertension in this experimental model.

Animals↗

[Suppression of myeloperoxidase gene expression by gamma-interferon].

The gene expression of myeloperoxidase (MPO) in HL60 cells, as tested by Northern blot analysis with a MPO gene probe, was markedly suppressed by treatment with gamma interferon (IFN-gamma)(200U/ml) for 9hr, whereas cytochemically detected MPO activity, cell surface antigen expression, and cell morphology remained unchanged even at 48hr after the treatment. IFN-gamma of 50U/ml was sufficient for the suppression at 24hr. When the HL60 cells treated with IFN-gamma (200U/ml) for 24hr were cultured in the absence of IFN-gamma for another 24hr, the transcript of MPO gene reverted to a level comparable to that of the HL60 cells cultured thoroughly in the absence of IFN-gamma, indicating the reversibility of the suppression. The suppression of MPO expression at RNA level, possibly independent of differentiation, is one of the biological activities exerted by IFN-gamma, which has not been previously reported.

Actins↗

[Detection of mRNA in megakaryocytes using in situ hybridization].

The usefulness of in situ hybridization for detecting mRNA encoding various kinds of proteins in megakaryocytic cell lines (K562, HEL and CMK) was examined. Using in situ hybridization, glycoprotein (GP) IIIa mRNA was found to be present in K562, HEL and CMK cells. Both GPIb and GPIIb mRNA were also present in HEL and CMK cells, while only HEL cells expressed platelet factor 4 mRNA. These findings were identical to those obtained with Northern blotting. It should be emphasized that in situ hybridization was useful to clearly define each cell expressing platelet specific protein mRNA. The expression of interleukin-6 (IL-6) and IL-6 receptor mRNA in mononuclear cells prepared from bone marrow aspirates was examined. In situ hybridization study demonstrated the presence of IL-6 receptor mRNA in the recognized megakaryocytes only, while IL-6 mRNA was found to be present in the megakaryocytes and a few mononuclear cells. These findings suggest that differentiation and proliferation of normal megakaryocytes might be controlled by an IL-6 autocrine loop, and detection of IL-6 receptor mRNA might be useful to identify megakaryocytes.

Blotting, Northern↗

Metoclopramide-induced parkinsonism and depression.

A 46-year-old female patient with metoclopramide-induced parkinsonism and depression was reported in view of the rarity of the concurrent development of these side effects. A risk of metoclopramide administration is suggested.

Depression↗

Maternal T cells of immunized pregnant mice induce immune suppression in their offspring.

The present study focused on the influence of maternal immunity during pregnancy on the responsiveness of the immune system(s) in offspring. Maternal immunization of pregnant mice with T-dependent foreign antigen sheep red blood cells (SRBC) induced suppression of anti-SRBC plaque-forming cell (PFC) responses in their offspring. We attempted to identify the cell species among the maternal lymphoid cells of the immunized pregnant mice that induced this suppression in their offspring, by separating the maternal cells into T cells, B cells and macrophages, or T-cell subsets, and then adoptively transferring them into other normal pregnant mice. The results demonstrated the following: first, maternal CD4+ T cells of immunized pregnant mice induced immune suppression in their offspring. Second, maternal T cells could be activated during pregnancy in the same fashion as in non-pregnant mice. The T-cell factor(s) for the immune suppression in offspring is produced not only by maternal T cells of immunized pregnant mice but also by T cells activated in non-pregnant mice. Third, cellular organization was required for maternal T cells to induce this immune suppression in their offspring.

Animals↗

[Norfloxacin-induced infectious mononucleosis (IM)-like syndrome with Stevens-Johnson syndrome].

A 77-year-old male who had suffered from an upper respiratory infection and had been given Norfloxacin (NFLX) on May 2, 1990, developed generalized erythema which did not subside with prednisolone. He was hospitalized on May 8, and Stevens-Johnson syndrome was diagnosed. The WBC was 115,400/microliter (Ly 61.0%, Aty Ly 39.5%). Sternal tap revealed hypercellular marrow with increased lymphocytes (48.5%; Aty Ly 24.5%) and eosinophils (7.0%). Clinical chemistry revealed slightly abnormal liver and renal function with LDH (1,745 IU/l) and IgE (803 IU/ml) elevation. No pathognomonic result was obtained with several viral antibodies. CD4+, CD8+ lymphocytes and the 4/8 ratio were 39%, 43% and 0.9, respectively. Clinical and laboratory abnormalities were normalized within 3 weeks after the discontinuance of all drugs. Positive lymphocyte stimulation test results were obtained by NFLX. While drug allergy is known to be a cause of IM-like syndrome, there are few reports regarding the subset characterization of the increased T lymphocytes. In this case, T lymphocytosis was remarkable, but the 4/8 ratio declined only slightly, indicating that CD4+ as well as C8+ cells were activated and increased, unlike IM. The record of this case helps to clarify the mechanisms of the lymphocyte activation shared and not shared by EBV-induced IM and IM-like syndrome.

Aged↗

[Detection of the deletion of interferon-alpha and beta genes in lymphoblastoid cells by PCR].

The HuIFN-alpha and beta genes were examined by the PCR method in the 11 human lymphoblastoid cell lines. The results showed that the homozygous deletion of HuIFN-alpha and beta genes was detected in 5 of 11 cell lines and in 5 of 11 cell lines, respectively. The deletions of both the HuIFN-alpha and beta genes were observed in 4 of 11 cell lines. One T cell leukemia cell line deleted only HuIFN-alpha gene, while the other T cell leukemia line deleted only HuIFN-beta gene. This suggests that the deletions of HuIFN-alpha and beta genes may be related the development of leukemia or lymphoma.

Burkitt Lymphoma↗

Effects of bradykinin and Des-Arg9-bradykinin on the ischemic rat heart.

In isolated rat hearts subjected to 30 min stop flow followed by 5 min reperfusion, Bradykinin (Bk), 1 and 0.1 microM, significantly decreased ventricular tachycardia and fibrillation, noradrenaline (NA) output at reperfusion as well as myocardial NA loss and lipid peroxidation, and preserved creatine kinase activity. Des-Arg9-Bk 0.1 microM had also similar effects. Hence, the active metabolite des-Arg9-Bk may be involved in the protective action of Bk, partly mediated by its inhibitory effect on NA liberation.

Animals↗

[Involuntary smoking in a workplace situation--discomfort of nonsmokers and interpersonal awareness of smokers].

A questionnaire survey was conducted to examine the socio-behavioral interaction between smokers and nonsmokers in a workplace situation. A socio-behavioral interaction is hypothesized to be centered around the subjective discomfort such as 'bothered feelings' towards involuntary smoking among nonsmokers. Study subjects were 1,134 nonsmokers and 1,457 smokers working in 21 small-scale production companies in Japan. Among nonsmokers, a combined 93.3% reported 'perceived exposure to smoking', 'always', 'often', or 'sometimes' compared to 6.6% reporting 'never'. Similarly, 74.6% experienced 'bothered feelings' 'sometimes', 'always', or 'often' compared to 25.3% reporting 'never'. A combined total of 39.4% expressed their discomfort to smokers 'sometimes', 'often', and 'always' compared to 60.6% who 'never' did. In contrast, 59.1% of smokers responded that they smoked with consideration of nonsmokers' presence (interpersonal awareness) 'sometimes', 'often', and 'always' compared to 41.0% for 'never'. 'Bothered feelings' among nonsmokers was significantly lower among those with past smoking history and correlated positively with 'perceived exposure to smoking' (rs = 0.22, p less than 0.001) and with 'expression of discomfort among both male (rs = 0.32, p less than 0.001) and female nonsmokers (rs = 0.34, p less than 0.001). Among male smokers 'interpersonal awareness' was significantly higher for those with less cigarette consumption and with past history of smoking cessation. A regression analysis was performed using mean scores calculated for smokers and nonsmokers of each workplace. Lower 'bothered feelings' of nonsmokers significantly correlated with higher 'interpersonal awareness' of smokers (r = -0.59, p less than 0.005). These finding imply the presence of socio-behavioral interactions between smokers and nonsmokers and thus suggest the significance of workplace education on involuntary smoking.

Adult↗

Induction of smg p21/rap1A p21/krev-1 p21 gene expression during phorbol ester-induced differentiation of a human megakaryocytic leukemia cell line.

smg p21A and -B (smg p21s) are ras p21-like small GTP-binding proteins (G proteins) with the same putative effector domain as ras p21s. Both smg p21A mRNA and smg p21B mRNA were detected in CMK, a human megakaryocytic leukemia cell line, and their levels were markedly elevated by treatment with 12-O-tetradecanoyl-phorbol-13-acetate (TPA), which caused the differentiation of this cell line into more mature megakaryocytes. The smg p21 protein molecules also increased during the TPA-induced differentiation of CMK cells. The mRNA level of glycoprotein IIb (GPIIb), a typical marker of the megakaryocytes, was increased by this treatment, but the time course of the increase in the smg p21 mRNA levels as more rapid than that of the increase in the GPIIb mRNA level. Ha-ras p21 mRNA was undetectable, but both Ki- and N-ras p21 mRNAs were detected in CMK cells and their levels were also increased during TPA-induced differentiation of CMK cells, although to a lesser extent than those of smg p21 mRNAs. Protein kinase C inhibitors inhibited the basal and TPA-induced smg p21A mRNA level, but cyclic AMP-elevating prostaglandin E1 or Ca(2+)-mobilizing ionomycin did not inhibit them. Cycloheximide enhanced the basal and TPA-induced smg p21A mRNA levels. Actinomycin D blocked the TPA-induced smg p21A mRNA levels, but showed no detectable effect on the elevated smg p21A mRNA level which was induced by pretreatment with TPA. A dramatic increase in the smg p21 mRNA levels was also observed in other leukemia cell lines during TPA-induced differentiation. These results suggest that TPA stimulated expression of the smg p21A gene, presumably through the action of protein kinase C at the transcriptional level rather than at the post-transcriptional level, in hematopoietic leukemia cells.

Alprostadil↗

[Mean platelet volume in diabetics].

Platelet size is a determinant of platelet function. As platelet size in diabetics has been reported to be larger than normals, we have measured mean platelet volume (MPV) in diabetics simultaneously with fasting plasma glucose, fructosamine, and hemoglobin A1. MPV was positively correlated with fasting plasma glucose and fructosamine. In a sequential observations for a few months of 22 patients, all of whom showed decreasing fasting plasma glucose, MPV decreased in 10 patients, however, increased in only 2 patients. These findings suggest that MPV would be affected with diabetic control.

Blood Glucose↗

[Cytoskeletal proteins abnormalities in olivopontocerebellar atrophy].

A highly sensitive silver technique for glial cytoplasmic inclusions in olivopontocerebellar atrophy (OPCA) was applied to 15 subjects with neurodegenerative disorders including 4 patients with OPCA, 4 patients with Joseph disease and with 3 normal control subjects, and the argyrophilic structures in the OPCA cases were immunocytochemically examined. As a result, the argyrophilic structures were found in the OPCA cases and Alzheimer cases. The argyrophilic structures included the white matter oligodendroglia, and neurons, astroglia and oligodendroglia in the putamen, pontine nucleus and inferior olivary nucleus. The pontocerebellar tracts and the surrounding white matter of the inferior olivary nucleus contained a small number of argyrophilic nerve fibers with a hollow structure, which were interpreted as myelin. Immunocytochemistry demonstrated that the oligodendroglia in the white matter had immunoreactivities to an paired helical filament (PHF), microtubule associated protein 5 (MAP5), tau and ubiquitin antiserum, and the astroglia in the white matters had an immunoreactivity to a MAP5 antiserum. In the putamen, pontine nucleus and inferior olivary nucleus, in addition to the immunoreactivities observed in the oligodendroglia, the neurons were immunoreactive for PHF, MAP5, tau and ubiquitin antisera, and the astroglia had the same immunoreactivities as the neurons except for being tau negative in the putamen. The nerve fibers in the pontocerebellar tract and inferior olivary nucleus capsule were strongly positive for myelin basic protein and negative for PHF antiserum. These findings indicate that the Gallyas positive argyrophilia in the OPCA subjects is closely associated with PHF or tau.

Aged↗

Age-related character of glomerular lesions in IgA nephritis. (2). Histopathological peculiarity in childhood onset.

Histopathological analysis was performed in the first renal biopsy specimens of patients over and under 10 yrs of IgA nephritis. They were divided clinically into two groups, the one with remission and the other with prolonged disease state respectively. Increased mesangial sclerosis, frequent occurrence of segmental glomerular lesions and tubulointerstitial change were significantly evident in the group with prolonged disease state. It is suggested that similar glomerular events are progressing in IgA nephritis which is carried over to adult age.

Adolescent↗

Significance of deposits and abnormalities of the glomerular basement membrane in tissue injury accompanying IgA nephropathy.

The glomerular injuries in 129 cases of IgA nephropathy (IgA-N) were examined ultrastructurally with special reference to the glomerular basement membrane (GBM) deposits and capillary loop abnormalities, and the correlation between these findings and the clinicopathological data was analyzed. The following results were obtained. 1) The degree of daily excretion of urine protein (UP) and creatinine clearance (Ccr) revealed a significant correlation with the degree of mesangial hypercellularities and the frequency of segmental lesions. 2) All sites of GBM deposits, and discontinuity and/or splitting among the GBM abnormalities showed a significant relation to the severity of proliferation and segmental lesions. 3) The GBM deposits, discontinuity and splitting showed a significant relation to the degree of UP and Ccr. We speculate therefore that capillary loop deposits and/or capillary loop discontinuity and splitting could represent histological prognostic factors for an unfavorable outcome in IgA nephropathy.

Adolescent↗

[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↗