PubMed Health⌕ Search

Biomedical subjects

M Nose

Publications and source records attributed to M Nose.

At least 91 records · Page 5Linked to original sources

Differential regulation of mRNA specific for beta 1- and beta 2-adrenergic receptors in human failing hearts. Evaluation of the absolute cardiac mRNA levels by two independent methods.

In human heart failure beta-adrenergic receptors are downregulated which contributes to the reduced responsiveness to positive inotropic beta-agonists in the diseased heart. The present study addressed the question whether the number of beta-adrenergic receptors in the failing human heart is regulated at the level of the mRNA and whether the absolute steady-state levels of subtype-specific mRNAs mirror the expression of receptor-subtype proteins in human heart. In a collaborative effort, two different and independent methods, performed in two independent laboratories, reverse transcription followed by polymerase chain reaction (RT-PCR) and RNase protection assays, were used to determine the absolute steady-state levels of beta 1- and beta 2-adrenergic receptor mRNAs in control (NF) and in failing human hearts. As determined by quantitative RT-PCR the beta 1-mRNA was significantly reduced from 0.98 +/- 0.12 (n = 10) to 0.49 +/- 0.11 pg/microgram total RNA in dilated cardiomyopathy (dCMP, n = 7) and to 0.40 +/- 0.11 pg/microgram total RNA in ischemic cardiomyopathy (iCMP, n = 8). The steady-state levels of mRNA specific for beta 2-adrenergic receptors also tended to be decreased but without reaching significance (NF: 0.16 +/- 0.05, dCMP: 0.11 +/- 0.03, iCMP: 0.13 +/- 0.04 pg/microgram total RNA). RNase protection assays revealed similar values. beta 1-mRNA was found to be significantly reduced from 1.22 +/- 0.22 in NF (n = 10) to 0.63 +/- 0.14 pg/microgram total RNA in dCMP (n = 5) and to 0.52 +/- 0.1 pg/microgram total RNA in iCMP (n = 8). The beta 2-mRNA also tended to be lower in dCMP and in iCMP as compared to NF but again without reaching significance (NF: 0.14 +/- 0.02, dCMP: 0.099 +/- 0.02, iCMP 0.107 +/- 0.02 pg/microgram total RNA). This is the first study to demonstrate in parallel by two different methods performed independently in two laboratories that the ratio of beta 1- and beta 2-adrenergic receptor densities in the left ventricle of the normal human heart of about 80/20 is closely related to the absolute steady state concentrations of their specific mRNA. In addition, the magnitude of the decrease in mRNA-levels of beta 1- and beta 2-adrenergic receptors in the failing human heart closely correlates with the decrease of the respective receptor proteins. These data suggest that the predominant regulation of beta-adrenergic receptors occurs at the mRNA level.

Adult↗

Expression of L-PHA-binding proteins in breast cancer: reconstitution and molecular characterization of beta 1-6 branched oligosaccharides in three-dimensional cell culture.

Expression of beta 1-6 branched oligosaccharides in human breast cancer cells was investigated in vivo and in vitro. Lectin histochemical and lectin blotting analyses of surgically resected specimens were performed using L-PHA (phaseolus vulgaris leukoagglutinin) lectin, which binds to beta 1-6 oligosaccharides. The glycoproteins bearing beta 1-6 oligosaccharides of breast cancer tissues were found to be 170 kD and 120 kD in molecular weight, and the former appeared to be an epitope of carcinoembryonic antigen (CEA). The beta 1-6 oligosaccharides were expressed in both cancer cell lines at the outer layer of the colonies when cultured in type I collagen, but not in agarose gel. No correlation was observed between beta 1-6 expression and cell cycle. The beta 1-6 oligosaccharides did not coincide with breast cancer-associated antigens, such as CEA, MUC1, and cathepsin D. The beta 1-6 oligosaccharides of these cell lines were markedly inhibited when swainsonine, a mannosidase II inhibitor, was added to the culture medium. The 120 kD molecule, which was obtained from MCF-7 cells cultured in type I collagen gel, was consistent with that of breast cancer tissues and was similar to lysosome-associated membrane glycoproteins (LAMPs). The results suggest that the glycoproteins bearing beta 1-6 branched oligosaccharides in human breast cancer incorporate an epitope of CEA and human LAMPs and that the expression of LAMPs may depend on their surrounding matrices and may play an important role in cancer invasion or metastasis.

Breast Neoplasms↗

Effect of Hachimi-jio-gan on scopolamine-induced memory impairment and on acetylcholine content in rat brain.

The effect of Hachimi-jio-gan (HJ) on scopolamine induced memory impairment was studied using a radial maze performance, the effect of HJ on the central cholinergic system as measured by acetylcholine (ACh) content, choline acetyltransferase (CAT) and acetylcholinesterase (AChE) activities was also examined. HJ (0.01-1.0 g/kg, p.o.) showed no influence on the radial maze performance. However, with the administration of scopolamine (0.5 mg/kg, i.p.), the number of the correct choices decreased and the number of the error choices increased. HJ (0.1 and 0.5 g/kg, p.o.) reduced this scopolamine-induced cognitive disturbance. The effect of HJ on ACh content and enzyme activities in the brain, frontal cortex, hippocampus and striatum was also investigated. In normal rats, HJ (0.1 and 0.5 g/kg, p.o. x 7 days) significantly increased ACh content in the frontal cortex, although it did not increased ACh content in the hippocampus. In scopolamine-treated rats, ACh content decreased in the brain regions examined. HJ (0.5 g/kg, p.o.) inhibited a decrease in ACh content in the frontal cortex, and with the same dosage of HJ increased CAT activity in the frontal cortex and AChE activity in the hippocampus. These results suggest that the behavioral effects of HJ may be related to its effect on the central cholinergic system.

Acetylcholine↗

Vascular lesions in mice with a deficit in Fas-mediated apoptosis and their transfer.

The lpr and gld genes are thought to result in an incapacity for Fas-mediated apoptosis of T and B cells and the development of subsequent autoimmune disease. A newly established gld-congenic strain of mice, MRL/MpTn-gld/gld (MRL/gld), was found to develop vascular lesions involving arteritis and glomerulonephritis (GN), which were similar to those observed in the MRL/Mp-lpr/lpr (MRL/lpr) strain. However, comparative studies with a C3H/HeJ strain bearing lpr or gld revealed that these lesions developed only in mice with an MRL background. We were successful in transferring GN to normal MHC-compatible gld/gld and irradiated +/+ mice by bone marrow cells of MRL/gld mice, but were unsuccessful using those of C3H/gld mice. Transfer of arteritis, however, was only successful in mice with an MRL background. Nephritogenic monoclonal antibodies obtained from an MRL/lpr and an MRL/gld mouse were shown to be bone marrow-derived and rich in clonal diversity, and at least two of these were capable of causing glomerular injury by different mechanisms. Development of GN and systemic arteritis in MRL/lpr and MRL/gld mice will be dependent not only on their incapacity for Fas-mediated apoptosis but also on bone marrow cells and peripheral cells with intrinsic defects.

Animals↗

Expression of adenylyl cyclase and G-protein beta subunit in end-stage human heart failure.

BACKGROUND: One of the abnormalities in end-stage human heart failure is desensitization of the beta-adrenergic signaling pathway, resulting in decreased adenylyl cyclase activity and cyclic adenosine 3',5'-monophosphate formation. This process includes changes in expression of receptors and G-protein alpha subunits. It was hypothesized that changes in the gene expression of G-protein beta subunits (Gbeta) and of adenylyl cyclase itself may contribute to the attenuation of activation of adenylyl cyclase. METHODS AND RESULTS: The hypothesis was tested by determining messenger RNA steady-state levels (Northern and slot-blot analyses) of adenylyl cyclase type V (a major isoform in adult myocardium) and Gbeta in the left ventricles of patients with terminal heart failure because of idiopathic dilated cardiomyopathy (n = 10) or ischemic heart disease (n = 7) and in the left ventricles of nonfailing donors (n = 5). Adenylyl cyclase type V messenger RNA was elevated by 85 +/- 25% in dilated cardiomyopathy and by 113 +/- 35% in ischemic heart disease (P < .05 vs nonfailing hearts). In contrast, Gbeta messenger RNA was unchanged in cardiomyopathy (3.48 +/- 0.18 pg/microgram total RNA vs nonfailing hearts 3.99 +/- 0.46) and decreased in ischemic heart disease (2.43 +/- 0.26, P < .01). CONCLUSION: The data indicate that gene expression of the major cardiac isoform of adenylyl cyclase (type V) seems increased in human end-stage heart failure. Therefore, attenuated adenylyl cyclase activity in this condition may not be the result of adenylyl cyclase messenger RNA downregulation. Similarly, the unchanged or decreased expression of Gbeta argues against changes in Gbeta contributing to this process.

Adenylyl Cyclases↗

Role of macrophages in the development of arteritis in MRL strains of mice with a deficit in Fas-mediated apoptosis.

The lpr and gld genes have been shown to encode the Fas antigen deletion mutant and the Fas ligand (FasL) mutant, respectively. An MRL strain of mice bearing the gld gene was observed to spontaneously develop granulomatous arteritis, similar to that in mice bearing the lpr gene, indicating that arteritis in this strain is due to an inefficient Fas-FasL interaction resulting in an incapacity for Fas-mediated apoptosis. The arterial lesions in both strains were characterized by a remarkable perivascular accumulation of activated macrophages bearing Mac-2 antigen, following the infiltration of CD4+ cells, and this resulted in the destruction of the arterial wall. Almost all of these infiltrating cells were Fas-positive, as determined in MRL/gld mice. Macrophage colony-stimulating factor (M-CSF), which is present at increased levels in MRL/lpr mice, but not in MRL/Mp- +/+ (MRL/+) mice, induced the expression of Mac-2 antigen and Fas antigen on spleen adherent cells of MRL/+ mice. Moreover, continuous infusion of M-CSF into the peritoneal cavity of subcutis of MRL/+ mice induced the release of oxygen radicals of peritoneal macrophages or granuloma formation associated with the massive accumulation of Mac-2+ cells, respectively. These findings suggest that macrophages in these mice, which may be activated by M-CSF and may avoid Fas-mediated apoptosis, play a critical role as effector cells in the destruction of arterial wall.

Animals↗

The effects of 18 alpha,beta-glycyrrhetinic acid on the hormonal induction of tyrosine aminotransferase in rat primary cultured hepatocytes.

The effects of 18 alpha,beta-glycyrrhetinic acid (18 alpha,beta-GA) on the hormonal induction of tyrosine aminotransferase (TAT) in rat primary cultured hepatocytes were investigated. Dexamethassone or glucagon used alone caused an increase in enzyme activity, and in combination their effects were additive. In the 18 beta-GA hepatocytes pretreated for 6 h, the dexamethasone-induced increase in the enzyme activity was slightly reduced in a dose-independent manner, and the glucagon-induced increase and the combined effects of these two inducers were significantly reduced in a dose-dependent manner. On the other hand, 18 alpha-GA, which was the isomer of 18 beta-GA, exerted no influence on the hormonally mediated increase in enzyme activity. Moreover, 18 beta-GA reduced the glucose release induced by glucagon in a dose-dependent manner and 18 alpha-GA did not. These results suggested that 18 beta-GA reduced the glucagon-mediated cell response in rat hepatocytes.

Animals↗

Expression of Phaseolus vulgaris leukoagglutinin-binding oligosaccharides in oral squamous cell carcinoma: possible association with the metastatic potential.

The expression of -GlcNAc beta 1-6Man-(beta 1-6) branched oligosaccharides in carcinoma cells has been considered to influence their metastatic potentials. In the present paper, the lectin histochemistry of oral squamous cell carcinomas obtained in biopsy from 34 patients with Phaseolus vulgaris leukoagglutinin (L-PHA), which potentially binds to N-glycosidic carbohydrates with beta 1-6 linked lactosamin antennae, was studied in order to analyze the relationship between their staining patterns and metastases. The L-PHA-binding oligosaccharides of the carcinomas were expressed on the cell surface in the following patterns: (i) all cells were positive for the staining ('positive'); (ii) some cells were positive but the rest of the carcinoma cells were negative ('weakly positive'); and (iii) all were negative ('negative'). Statistical analysis revealed that the incidence of the metastasis to regional lymph nodes in the 'positive' cases was significantly higher than that in the 'negative' cases. Moreover, the number of the CD14 positive cells including macrophages in the stroma adjacent to the carcinomas in the 'positive' cases was less than that in the 'negative' or 'weakly positive' cases. The expression of L-PHA-binding oligosaccharides in oral squamous cell carcinoma may be responsible for their metastatic potential to regional lymph nodes, possibly including their ability to escape macrophage recognition.

Carcinoma, Squamous Cell↗

A cytotoxic nonstructural protein, NS1, of human parvovirus B19 induces activation of interleukin-6 gene expression.

We examined the biological function of a nonstructural regulatory protein, NS1, of human parvovirus B19. Because of the cytotoxic activity of NS1, human hematopoietic cell lines, K562, Raji, and THP-1, were established as transfectants which produce the viral NS1 protein upon induction by using bacterial lactose repressor/operator system. NS1 was significantly produced in the three transfectant cells in an inducer dose- and time-dependent manner. Surprisingly, these three transfectants secreted an inflammatory cytokine, interleukin-6 (IL-6), in response to induction. However, no production of other related cytokines, IL-1beta, IL-8, or tumor necrosis factor alpha, was seen. Moreover, NS1-primed IL-6 induction was transiently demonstrated in primary human endothelial cells. Analysis with luciferase reporter plasmids carrying IL-6 promoter mutant fragments demonstrated that NS1 effect is mediated by a NF-kappaB binding site in the IL-6 promoter region, strongly implying that NS1 functions as a trans-acting transcriptional activator on the IL-6 promoter. Our novel finding, IL-6 induction by NS1, supports the possible relationship between parvovirus B19 infection and polyclonal activation of B cells in rheumatoid arthritis and indicates that NS1 protein may play a significant role in the pathogenesis of some B19-associated diseases by modulating the expression of host cellular genes.

Animals↗

IgA nephropathy with poorly developed lymphoepithelial symbiosis of the palatine tonsils.

Tonsillar abnormalities have been observed in patients with IgA nephropathy (IgAN). In addition, it has been suggested that reticulization of tonsillar crypt epithelium is important in tonsillar immunity. Therefore, we investigated reticulization of this area in patients with IgAN (14 cases) and compared results with those of control patients who exhibited recurrent tonsillitis or tonsillar hypertrophy (12 cases). Immunohistochemical staining of antikeratin antibody PKK1 was employed to visualize reticulization. Tonsils of controls showed well developed reticular crypt epithelia with lymphoepithelial symbiosis and the nonreticulated area was less than 7% of the total crypt epithelia per overall section. In IgAN tonsils, however, nonreticulated crypt epithelium was frequently observed and, in the advanced stage of IgAN, exceeded 50% of total crypt epithelia. The extent of glomerular damage in IgAN patients correlated significantly with the percentage of the area of nonreticulated crypt in palatine tonsils with a correlation coefficient of 0.91. Considered together with our finding that PKK1-positive epithelial reticular cells strongly expressed HLA-DR antigens in normal tonsils, the low level of reticulization in IgAN patients may induce the unusual immunity responsible for the pathogenesis of IgAN.

Adolescent↗

Messenger RNA expression and immunological quantification of phospholamban and SR-Ca(2+)-ATPase in failing and nonfailing human hearts.

OBJECTIVES: Human heart failure is associated with prolonged relaxation and prolonged Ca2+ transients which indicates an impaired function of the sarcoplasmic reticulum (SR) and may be detrimental for cardiac function. Controversy exists whether the altered SR function is accompanied by changes in the expression of phospholamban (PLB) and cardiac SR-Ca(2+)-ATPase (SERCA2) on mRNA and/or protein levels. METHODS: We determined mRNA and/or protein levels for PLB and SERCA2 in the same left ventricular tissue of patients undergoing heart transplantation due to idiopathic dilated cardiomyopathy (IDC) or ischemic cardiomyopathy (ICM) in comparison to left ventricular tissue from nonfailing human hearts (NF). Total protein extracts were prepared and subjected to SDS gel electrophoresis. PLB and SERCA2 were identified with specific antibodies. Total RNA was isolated and hybridized with 32P-labeled cDNAs for human PLB and rat SERCA2. RESULTS: Hybridization revealed the three expected mRNAs with the PLB probe (3.3 kb, 1.9 kb and 0.6 kb) and a single band with the SERCA2 probe (4.5 kb). Determination of respective proteins by immunoblotting revealed unchanged protein levels for PLB and SERCA2, whereas the mRNA levels for PLB and SERCA2 were reduced by about 30% and 50%, respectively. CONCLUSIONS: These data show the level of SERCA2 and PLB protein and mRNA in the same hearts. The reduced mRNA level of SERCA2 and PLB is in accordance with previous data. However, the unchanged protein levels may indicate that the diminished RNA expression is not accompanied by a corresponding decrease for these proteins in human heart failure. These data also show that the altered SR function in human heart failure cannot be explained by altered protein levels of PLB and SERCA2. Furthermore, it is suggested that extrapolations from cardiac mRNA levels to protein expression may be misleading.

Adenosine Triphosphate↗

Arteritis in a novel congenic strain of mice derived from MRL/Lpr lupus mice: genetic dissociation from glomerulonephritis and limited autoantibody production.

An MRL/Mp strain of mice bearing the Fas deletion mutant gene, lpr (MRL/lpr), spontaneously develop systemic vasculitis and glomerulone phritis in the same individual, and both have been thought to be associated with an increase in circulating immune complexes and autoantibodies. However, the genetic basis of these diseases is poorly understood. A novel recombinant congenic mouse strain, McH5-lpr/lpr, which was established by rearrangement of the genetic background of MRL/lpr mice by hybridization with C3H/HeJ-lpr/lpr mice, developed severe granulomatous polyarteritis, as did the MRL/lpr strain, but not glomerulonephritis. Serum levels of anti-DNA and anti-myeloperoxidase antibodies in these mice were significantly reduced, as compared with MRL/lpr mice, although rheumatoid factors were not. These results indicate that each of these two diseases, arteritis and glomerulonephritis, is under the control of different background gene(s), suggesting a different pathological basis of these diseases, and that anti-DNA and anti-myeloperoxidase autoantibodies appear to have a limited pathogenic role in granulomatous arteritis in the mouse strain described.

Animals↗

Reduced reticulization of palatine tonsils with IgA nephropathy.

Tonsillar abnormalities have been observed in patients with IgA nephropathy (IgAN). In addition, it has been suggested that the reticulization of tonsillar crypt epithelium is important in tonsillar immunity. Therefore, we investigated reticulization of this area in patients with IgAN (10 cases) and compared results with those of control patients who exhibited recurrent tonsillitis or tonsillar hypertrophy (12 cases). Immunohistochemical staining of anti-keratin antibody PKK1 was employed to visualize reticulization. Tonsils of controls showed well developed reticular crypt epithelia with lymphoepithelial symbiosis, and the non-reticulated area was less than 7% (mean 1.9%, range 0-6.3%) of the total crypt epithelia per overall section. In IgAN tonsils, however, non-reticulated crypt epithelium was frequently observed and, in the advanced stage of IgAN, exceeded 50% (mean 62%, range 50-69%) of total crypt epithelia. The extent of glomerular damage in IgAN patients correlated significantly with the percentage of the area of non-reticulated crypt epithelia in palatine tonsils with a correlation coefficient of 0.91. Considering together with our finding that PKK1-positive epithelial reticular cells strongly expressed HLA-DR antigens in normal tonsils, the low level of reticulization in IgAN patients may induce the unusual immunity responsible for the pathogenesis of IgAN.

Adolescent↗

A simple method based on PCR for detecting the relative mRNA amounts of the four mouse IgG subclasses.

A simple method based on the polymerase chain reaction (PCR) was developed for detecting the relative mRNA amounts of the four mouse IgG subclasses in total RNA samples and is described in this report. The main features of this method are, first, cDNA amplification including VH through the constant region(CH2 domain) of each IgG subclass with a set of consensus PCR primers(VH1BACK and 32P-labeled C gamma 32), and secondly, cleavage of the amplified DNA fragments with BamHI and XhoI endonucleases which act at distinct cleavage sites in the constant region of each IgG subclass. The radioactive intensities of the different sized fragments separated on polyacrylamide gel were used to show the relative amounts of IgG subclasses at the RNA level. This method provides clear detection of each IgG subclass using RNA samples from tissues in which Ig-producing cells are rare.

Animals↗

Accumulation of plasma cells in atherosclerotic lesions of Watanabe heritable hyperlipidemic rabbits.

By screening a cDNA library constructed from aortic total RNA derived from Watanabe heritable hyperlipidemic (WHHL) rabbits by differential hybridization, we have obtained a cDNA encoding the kappa light chain of immunoglobulin. Northern blot analysis of total RNA prepared from aortas of WHHL and normal rabbits of various ages revealed that this light-chain mRNA accumulates gradually with age in aortas in WHHL rabbits. Northern blotting and in situ hybridization with an antisense oligonucleotide specific to rabbit immunoglobulin gamma heavy-chain mRNA also detected accumulation of this heavy-chain mRNA in advanced lesions of WHHL rabbit aortas. Moreover, immunohistochemical and electron microscopic analyses demonstrated the presence of plasma cells in the atherosclerotic lesions.

Amino Acid Sequence↗

Towards the specification of consecutive steps in macromolecular lignin assembly.

When Pinus taeda cell suspension cultures are exposed to 8% sucrose solution, the cells undergo significant intracellular disruption, irregular wall thickening/lignification with concomitant formation of an 'extracellular lignin precipitate. However, addition of potassium iodide (KI), an H202 scavenger, inhibits this lignification response, while the ability to synthesize the monolignols, p-coumaryl and coniferyl alcohols, is retained. Lignin synthesis (i.e. polymerization) is thus temporarily correlated with H202 generation, strongly implying a regulatory role for the latter. Time course analyses of extracellular metabolites leading up to polymer formation reveal that coniferyl alcohol, but not p-coumaryl alcohol, undergoes substantial coupling reactions to give various lignans. Of these, the metabolites, dihydrodehydrodiconiferyl alcohol, shonanin (divanillyl tetrahydrofuran) and its apparent aryl tetralin derivative, cannot be explained simply on the basis of phenolic coupling. It is proposed that these moieties are the precursors of so-called reduced substructures in the lignin macromolecule. This adds a new perspective to the lignin assembly mechanism.

Cell Wall↗