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T Noguchi

Publications and source records attributed to T Noguchi.

At least 685 records · Page 38Linked to original sources

[Regulation of pyruvate kinase gene expression and its clinical application].

Pyruvate kinase (PK), an important glycolytic enzyme, has two genes per haploid genome in mammals and each gene encodes two isozymes. The L gene produces the L- and R-types using alternative promoters. The M gene generates the M1- and M2-types by alternative RNA splicing. Expression of the PK isozymes is tissue-specific and regulated developmentally. Carcinogenesis apparently reverses the developmental process. Expression of the L-type is regulated by dietary and hormonal factors. These regulations occurred at post-transcriptional as well as transcriptional levels. The transcription of hepatic L-type PK is stimulated by insulin and inhibited by glucagon. The insulin action requires ongoing protein synthesis and metabolism of glucose, and is enhanced by glucocorticoid. Dietary fructose also stimulates expression of the L-type in liver, kidney, and small intestine, but its mechanism is dependent on tissues, and on plasma insulin levels in the case of the liver. In normal liver, the fructose induction is explained by stimulation of gene transcription. On the other hand, fructose acts mainly at the post-transcriptional level in diabetic liver and other tissues. These fructose effects are attributable to common metabolite(s) of fructose and glycerol. Studies on transgenic mice indicate that the 5'-flanking region up to -3 kb of the L-type PK gene contains cis-acting elements responsible for insulin regulation and tissue-specific expression of the L-type. Further analysis using a transient expression assay revealed the presence of multiple elements necessary for expression of the L-type in hepatocytes in the region up to -170b.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

[Malignant lymphoma diagnosed by the pericardial biopsy].

The biopsy findings of malignant lymphoma involving the pericardium in a 69-year-old male were reported. The initial presenting symptoms were heart failure followed by rapidly progressive complete heart block. Pacemaker was inserted. Chest roentgenogram showed a marked left pleural effusion. An echocardiogram demonstrated pericardial fluid. The diagnosis of lymphoma was suggested by gallium isotope study with markedly increased isotope uptake in heart, and was subsequently confirmed by pericardial biopsy. After chemotherapy the pleural effusion was decreased and the uptake of gallium disappeared. While the diagnosis of cardiac involved lymphoma was hard antemortem, experience in this case suggests that gallium isotope study and pericardial biopsy are helpful in establishing the correct diagnosis.

Aged↗

[The role of bacteria on facial rosacea-like dermatitis in adult type atopic dermatitis].

To investigate the role of bacteria on facial rosacea-like dermatitis lesion in adult type atopic dermatitis, we measured the numbers of bacteria on the skin, nasal and pharyngeal surface of each individual, and then examined its sensitivity to antibiotics. The numbers of bacteria on the surface of skin increased according to the severity of skin eruption. Staphylococcus aureus was detected from the skin and nasal surface more than pharyngeal surface. Bacteria on the pharyngeal surface were both staphylococcus aureus and haemophilus parainfluenzae. Therefore, it is suggested that bacterial flora on the pharynx is different from those of the skin and nose. The treatment with antibiotics was effective for exudative lesions, whereas lichenified lesion did not respond to antibiotic therapy. These results suggest that bacteria on the skin surface are one of precipitating factors of the rosacea-like dermatitis of atopic dermatitis.

Adolescent↗

[Treatment of adult type atopic dermatitis (AD) with bacterial vaccine prepared from individual cases (I)--Clinical study].

Bacteria on the skin surface are well known to be one of the precipitating factors of AD. We have treated 68 severe cases of adult type AD with bacterial vaccines prepared for individual cases. Bacteria were collected from lesional skin of each individual and cultured. More than 50% of cases (36/68) showed improvement clearly. Five out of 9 cases without topical steroid showed good response to this treatment. In regard to its clinical response it is suggested that the treatment should be continued for at least 1-2 years, because these cases treated for less than 1 year have high risk of recurrence. Five cases responded excellent showed complete remission of dermatitis for 10 months to 2 years after stopping of this treatment. These results suggest that bacterial vaccine can be beneficial for the treatment of severe cases of adult type AD, which did not respond to other therapy.

Adolescent↗

[Treatment of adult type atopic dermatitis (AD) with bacterial vaccine prepared from individual cases (II)--The mechanism].

Sixty eight cases with severe adult type AD treated by bacterial vaccine were classified into 2 subgroups, effective and ineffective cases. And the differences of these 2 subgroups were examined by various laboratory data. In effective groups, specific IgG antibody level against bacteria increased to correlate to the clinical course. In contrast, ineffective groups were not changed the antibody level. There were no significant differences between these 2 subgroups concerning results of specific IgE antibody level against bacteria. Decrease of CD4/CD8 ratio was more prominent in effective groups than ineffective groups after treated for 6 months. It is known that bacteria and bacterial products (peptidoglycan and endotoxin etc) cause release of histamine. Our results support that the elevation of specific IgG antibody against bacteria and enhanced cell mediated immunity are decreased the numbers of bacteria on the skin surface and improved irritable skin. These effects may be inhibit histamine release induced by bacteria, so therefore we suggest that general skin condition and pruritus with AD will be improved by the treatment.

Adult↗

[Inhalation anesthetic therapy of status asthmaticus].

Status asthmatics is characterized pathologically by bronchial smooth muscle spasm, and mucous plugging of the small airways. Clinically, it is characterized by the disturbance of gas exchange. In severe cases, unresponsive to standard therapy (including oxygen, epinephrine, aminophylline and steroids, artificial ventilation, tracheobronchial lavage and inhalation), anesthetic therapy should be started without delay. Inhalation anesthetics, halothane or ether, have potent bronchodilating properties which facilitate the removal of mucous plugging. We reported nine cases with status asthmatics treated by inhalation anesthetic therapy. Halothane (0.5-3.0%) was used in all cases, ether (1.5-3.0 ml/kg) was used in five cases. The duration of anesthesia was 0.5 to 13.5 hours. In three halothane anesthesia cases, blood pressure was reduced before there was improvement in wheezing, so we were forced to change halothane to ether. In all cases, the symptoms of status asthmatics were improved, but two patients died due to other complications. We recommended the following method, viz that halothane be administered at first, and be changed to ether in order to maintain circulatory movement.

Adult↗

Effect of dietary proteins on the plasma immunoreactive insulin-like growth factor-1/somatomedin C concentration in the rat.

Plasma immunoreactive insulin-like growth factor-1/somatomedin C (IR-IGF-1) was determined in rats fed for 1 week on a protein-free diet, or diets containing gluten, gluten supplemented with lysine and threonine, maize-gluten meal (with arginine), maize-gluten meal (with arginine) supplemented with tryptophan and lysine, or casein. IR-IGF-1 concentration was higher in the arterial plasma of rats fed on a diet containing casein at 120 g/kg diet (4-8 U/ml) than in rats fed on a protein-free or a low-casein (50 g/kg diet) diet (1.5-2 U/ml). The plasma of rats fed on gluten or maize-gluten meal as the protein source showed intermediate values. However, giving a diet containing an amino acid mixture as recommended by the National Research Council (1978) but deprived of lysine or tryptophan did not affect significantly the plasma IR-IGF-1 concentration. Total IGF-1 concentration (which was measured immunologically after extraction of the plasma with acid-ethanol) was also lower in the rats fed on the protein-free diet than in those fed on the casein (120 g/kg diet) diet. The ratio IR-IGF-1:total IGF-1 was higher in the rats fed on the casein diet (120 g casein/kg diet) than in those fed on the protein-free diet. The results suggest an important influence of IR-IGF-1 or IR-IGF-1:total IGF-1 ratio on protein anabolism and nutrition. IR-IGF-1 and total IGF-1 were found in the fractions of molecular weights 40 kDa and 150 kDa after gel filtration of rat plasma. A larger amount of IGF-1 was recovered in the fraction of 150 kDa in the rats fed on the casein diet. 125I-IGF-1 added to the plasma of rats fed on the protein-free diet was found mainly in the fraction of 40 kDa after gel-filtration. On the other hand, 125I-IGF-1 added to the plasma of rats fed on the gluten or casein diets was mainly recovered in the free IGF-1 fraction. The results suggest that IGF-binding protein(s) of molecular weight about 40 kDa was not saturated with IGF-1 in the rats fed on the protein-free diet. The results indicate the important role of IGF-1 and its binding proteins in the regulation of protein metabolism in rats.

Animals↗

Characterization of the 5' flanking region of rat glucokinase gene.

The rat glucokinase (GK) gene containing the first exon was isolated and its 5' flanking region was characterized by the bacterial chloramphenicol acetyltransferase (CAT) assay. A transient expression assay with a series of 5' deletion constructs (-5.5 k to -48) of GK-CAT fusion genes indicated that the 5' flanking sequence up to nucleotide -87 was sufficient for promoter activity in adult rat hepatocytes, but its activity was much weaker than that of the SV40 enhancer/promoter. Similar promoter activity was also detected in dRLh-84 hepatoma cells, which do not express glucokinase. Insulin treatment caused no change in the CAT activity of hepatocytes transfected with the fusion genes. These results suggest that the 5' flanking region of the glucokinase gene up to -5.5 k does not contain enhancer elements responsible for tissue-specific expression or insulin regulation.

Animals↗

Effects of nutrients and insulin on transcriptional and post-transcriptional regulation of glucose-6-phosphate dehydrogenase synthesis in rat liver.

The transcriptional and post-transcriptional regulation of glucose-6-phosphate dehydrogenase induction of rat liver was investigated using a cDNA cloned in our laboratory. By feeding a carbohydrate/protein diet to fasted rats, the mRNA concentration and enzyme induction of glucose-6-phosphate dehydrogenase (EC 1.1.1.49) reached maximal levels about 10-fold those in the fasted rats at 16 h and 72 h, respectively, whereas the transcriptional rate was increased about 3-fold in 6 h. In the protein fed (without carbohydrate) group, both the mRNA concentration and enzyme induction were increased to about 60% of the levels in the carbohydrate/protein fed group and in the group fed on a carbohydrate diet (without protein) to 30-40%. Further, dietary fat significantly reduced the transcriptional rate, mRNA concentration and enzyme induction to less than half, suggesting that dietary fat primarily reduced transcription. Thus, dietary nutrients appear to be involved in the steps preceding the translation. On the other hand, in diabetic rats, the transcriptional rate was significantly decreased as compared to the normal level and restored by insulin-treatment in 4 h. The mRNA concentration was very low in diabetic rats, and was restored to the normal level by insulin treatment in 8 h, and was half restored by fructose feeding. However, the enzyme induction of glucose-6-phosphate dehydrogenase was scarcely restored by fructose, unless accompanied by insulin treatment. Thus, it is suggested that insulin is involved in translation as well as in transcription. Further, the insulin-dependent increase of glucose-6-phosphate dehydrogenase mRNA was blocked by cycloheximide, suggesting that synthesis of a peptide is required.

Animals↗

The endocrine pancreas of alloxan-diabetic rats: microangiopathy as revealed by electron microscopy.

We studied the microvasculature of the pancreatic islet with an electron microscope using 15 alloxan-diabetic and 16 control rats. These animals were morphologically examined at 2 weeks, 1, 2, and 4 months after alloxan injection (diabetic rats) or at comparable times (control rats). Control rats were non-diabetic, either sequentially treated with glucose and alloxan (injected controls) or not subjected to any medication (non-treated controls). Body weights, plasma glucose levels, and erythrocyte glycosylated hemoglobin (HbA1c) concentrations were also measured at intervals. All the diabetic rats exhibited retarded growth, hyperglycemia, and increases in HbA1c concentrations. The primary changes in diabetic islet capillaries can be grouped into four categories: (1) narrowing and closing of capillaries and occurrence of possible acellular capillaries, (2) formation of perivascular edema, (3) bulging and projection of endothelial cytoplasm, and (4) perivascular proliferation of collagen-like fibrils together with thickening of the basement membrane. These changes tended to worsen with diabetic duration. They are regarded as pathognomonic for diabetic microangiopathy. It is presumed that the present microvascular lesions of the islet play an important role in the pathogenesis and advancement of the diabetic state.

Animals↗

Membrane IL-1 induces bone resorption in organ culture.

We have studied the role of the membrane-associated form of IL-1 on bone resorption in vitro. Murine macrophages of the P388D1 cell line stimulated with LPS, subsequently fixed with paraformaldehyde, induced the proliferation of C3H/HeJ mouse thymocytes in the presence of a submitogenic concentration of Con A. Membrane IL-1 on P388D1 cells stimulated with LPS induced bone resorption in organ cultures of neonatal BALB/c mouse calvaria. Polyclonal antibodies directed against membrane IL-1 and soluble IL-1 from P388D1, and monospecific rabbit anti-murine rIL-1 alpha serum neutralized the membrane IL-1 activity, as measured by the thymocyte proliferation. In addition, these antibodies suppressed the bone resorption induced by membrane IL-1. The bone resorption induced by membrane IL-1 required direct contact between mouse calvaria and membrane IL-1. Salmon calcitonin strongly suppressed the calcium release from mouse calvaria in the presence of membrane IL-1. Indomethacin partially inhibited the bone resorption induced by membrane IL-1 on P388D1 cells. Moreover, membrane IL-1 on LPS-stimulated BALB/c mouse peritoneal macrophages or LPS-stimulated osteoblastic cells from BALB/c mouse calvaria induced bone resorption in vitro. These results suggest that membrane IL-1 on macrophages and osteoblastic cells may have a significant role in inflammatory bone resorption in vivo.

Animals↗

Effects of insulin and fructose on transcriptional and post-transcriptional regulation of malic enzyme synthesis in diabetic rat liver.

Insulin action on regulation of hepatic malic enzyme has been investigated in comparison with fructose, using streptozotocin-induced diabetic rats. Insulin-treatment caused a 2.8-fold increase in the transcriptional rate of malic enzyme (EC 1.1.1.40) after 8 h, and a 5-fold increase in the mRNA concentration of the liver. In Northern blot analysis, we demonstrated that after insulin treatment, the nuclear mRNA of malic enzyme tended to increase more rapidly than the total cellular mRNA. Therefore, it is suggested that the nuclear mRNA was primarily increased by insulin. The insulin-dependent increase of malic enzyme mRNA was blocked by cycloheximide, suggesting that synthesis of a peptide is required. On the other hand, by feeding a high-fructose diet to diabetic rats, the malic enzyme mRNA concentration was considerably increased, though with a delayed peaking in comparison with the insulin-treated animals, whereas the transcriptional rate was not significantly increased. Dietary fructose may stabilize the transcripts. Fructose increased the enzyme level far less than the mRNA level. These results suggest that insulin is required in both the translational and transcriptional regulation of malic enzyme.

Animals↗

Alanine:glyoxylate aminotransferase is present as the apoenzyme in the peroxisomes of chicken kidney.

The subcellular distribution of alanine:glyoxylate aminotransferase in chicken kidney was examined by centrifugation in a sucrose density gradient. The enzyme was found to be present as the apoform in the peroxisomes and as the holoform in the mitochondria. Alanine:glyoxylate aminotransferase in different mammalian kidneys were all present as the holoenzyme in the mitochondrial and soluble fractions.

Animals↗

Effects of brefeldin A on the synthesis and secretion of egg white proteins in primary cultured oviduct cells of laying Japanese quail (Coturnix coturnix japonica).

We investigated the effect of brefeldin A (BFA) and monensin on the secretion of egg white proteins in primary cultured oviduct cells. Monensin inhibited the secretion of egg white proteins, but this drug also caused morphological changes of the cells and inhibited their protein synthesis. BFA inhibited protein secretion without any remarkable morphological changes of the cells and without significant inhibition of protein synthesis. In the presence of BFA at 1 microgram/ml, only 10% of synthesized ovalbumin was secreted into the medium even after 6 h. A similar effect of BFA was shown in the case of conalbumin. When the cells were cultured in the presence of BFA, precursors of mature ovalbumin accumulated which were not secreted. Their affinity for lectin binding affinity columns (Con-A Sepharose and WGA-agarose) suggested that they contained immature high-mannose-type chains. The above results suggest that the conversion of high-mannose-type oligosaccharides to hybrid-type ones, which is not usually observed in mammalian species but only in avian oviduct tissues, proceeds between the Golgi complex and the endoplasmic reticulum.

Animals↗

Degradation of uric acid in fish liver peroxisomes. Intraperoxisomal localization of hepatic allantoicase and purification of its peroxisomal membrane-bound form.

Urate-degrading enzymes such as uricase, allantoinase, and allantoicase are located in the peroxisomes of marine fish liver (Noguchi, T., Takada, Y., and Fujiwara, S. (1979) J. Biol. Chem. 254, 5272-5275). On the basis of intraperoxisomal localization of hepatic allantoicase, 13 different fishes were classified into two groups: mackerel group and sardine group. Allantoicase is located on the outer surface of the peroxisomal membrane in the mackerel group and in the peroxisomal soluble matrix in the sardine group. The peroxisomal membrane enzyme and the peroxisomal matrix enzyme are not distinguishable on the basis of the number and molecular weight of the subunits, but differ in isoelectric point and electrophoretic mobility. The molecular weight of the fish allantoicase subunit is identical with that of the small subunit (allantoicase subunit) of amphibian allantoinase-allantoicase complex, suggesting that the subunit of fish allantoicase changed to the small subunit of the amphibian complex during evolution: allantoinase and allantoicase are present as a complex in amphibian liver (Noguchi, T., Fujiwara, S., and Hayashi, S. (1986) J. Biol. Chem. 261, 4221-4223).

Animals↗