Search PubMed⌕ Search

Biomedical subjects

S Takami

Publications and source records attributed to S Takami.

At least 73 records · Page 4Linked to original sources

Atherosclerotic disease in marked hyperalphalipoproteinemia. Combined reduction of cholesteryl ester transfer protein and hepatic triglyceride lipase.

Hyperalphalipoproteinemia (HALP) has been regarded as a beneficial state accompanied by a longevity syndrome. However, we reported the cases of markedly hyperalphalipoproteinemic subjects with juvenile corneal opacification. The patients had reduced postheparin hepatic triglyceride lipase (HTGL) activities, and one of them has recently been identified to be homozygous for a missense mutation in exon 15 (D442: G) in the cholesteryl ester transfer protein (CETP) gene. In the current study, to elucidate the clinical significance of and atherogenicity in marked HALP, we determined the incidence of atherosclerotic cardiovascular disease (ACD) in patients with marked HALP and characterized the lipoprotein abnormalities in those who had ACD, focusing especially on CETP and HTGL. The subjects were 201 patients (111 males and 90 females) with marked HALP ( > or = 2.58 mmol/L [100 mg/dL]), 67% of whom were demonstrated to have the CETP gene mutations in the intron 14 splice donor site or in exon 15. Their mean age was 54 +/- 15 years. Plasma levels of total cholesterol, HDL cholesterol, and triglyceride in all subjects were 6.28 +/- 1.78, 3.15 +/- 0.90, and 1.08 +/- 0.53 mmol/L, respectively. Ten of the male patients (9.0%) and two of the female patients (2.2%) had apparent ACD such as myocardial infarction, angina pectoris, and peripheral vascular diseases. Ten patients with HALP who had ACD were identified to be heterozygotes for CETP deficiency. To further clarify the characteristics of marked HALP in patients with ACD, we compared the plasma lipids, lipoproteins, CETP, and HTGL activities between heterozygotes for CETP deficiency who were with and without ACD.

Adult↗

Enhanced predictability of myocardial infarction in Japanese by combined genotype analysis.

To explore the genes responsible for myocardial infarction and restenosis after percutaneous transluminal coronary angioplasty, we performed association studies of the polymorphisms of the angiotensinogen and angiotensin-converting enzyme (ACE) genes. In the first study, normotensive myocardial infarction patients (n = 103) and control subjects (n = 103), who were matched for established risk factors with the myocardial infarction patients, were randomly selected. The angiotensinogen-TT genotype (T indicates threonine instead of methionine at position 235) was more frequent in the myocardial infarction group than in the control group (P < .05). The ACE-DD genotype (D indicates a deletion polymorphism in intron 16) was also more frequent in the myocardial infarction group (P < .0001). The odds ratio estimated by the combined analysis of the angiotensinogen-TT and ACE-DD genotypes (11.2) was markedly increased compared with that estimated separately from the angiotensinogen-TT (1.75) or ACE-DD (4.43) genotype. In the second study, we investigated 91 consecutive patients with acute myocardial infarction who underwent successful direct angioplasty. Combined analysis showed that the angiotensinogen-TT genotype did not enhance the predictability of myocardial infarction from the ACE-DD genotype. In conclusion, the angiotensinogen-TT genotype is a predictor for myocardial infarction, as well as the ACE-DD genotype, and the combined analysis of the angiotensinogen-TT and ACE-DD genotypes further enhanced the predictability of myocardial infarction in Japanese, suggesting its future clinical usefulness.

Angioplasty, Balloon, Coronary↗

Gap junction protein locus on chromosome 18 cosegregates with body weight in the spontaneously hypertensive rat.

To detect genetic predisposing factors for hypertension, we screened the genome of the spontaneously hypertensive rat (SHR). We determined the genotypes of all F2 rats at polymorphic sites between the two strains, using the DNA of F2 rats derived from mating of SHR and Wistar-Kyoto rats (WKY). Cosegregation analysis was conducted to assess whether the genotypes of polymorphic markers associate with any phenotypic parameters such as directly measured blood pressure, heart rate or body weight. All measurements in F2 rats were performed at 15 weeks of age. Two polymorphic markers on chromosome 18 cosegregated with body weight. Gap junction protein (heart connexin 43) gene showed the most significant association with body weight as a recessive trait, but no association was noted with other parameters. We conclude that the gap junction protein locus is a new candidate for the determinant gene of body weight in SHR.

Analysis of Variance↗

Innervation in human taste buds and its decrease in Alzheimer's disease patients.

The innervation in human taste buds of the foliate and circumvallate papillae was studied immunohistochemically using several neuronal markers in patients with Alzheimer's disease (AD) and their control (ADC) patients. Antisera to protein gene product 9.5 (PGP 9.5), neuron-specific enolase (NSE), tyrosine hydroxylase (TH), dopamine-beta hydroxylase (DbetaH) and calcitonin gene-related peptide (CGRP) were used in immunofluorescence and streptavidin-biotin-peroxidase complex studies. The antiserum to PGP 9.5 stained a greater number of intragemmal nerve fibers in taste buds than that of other antisera. PGP 9.5 immunoreactivity was strictly localized in the nerve fibers, whereas NSE immunoreactivity was observed not only in the nerve fibers, but also in taste bud cells. Intragemmal TH- and DbetaH-immunoreactive nerve fibers were not identified in taste buds. Only a few intragemmal nerve fibers immunoreactive for anti-CGRP antiserum were observe in a small number of taste buds. Furthermore, quantitive analysis in AD and ADC patients demonstrated that the mean number of PGP 9.5-immunoreactive intragemmal nerve fibers in taste buds of the foliate and circumvallate papillae decreased significantly in AD patients. These results indicated that PGP 9.5 is a most suitable molecular marker for the demonstration of the extrinsic innervation in human taste buds, and that the decreased innervation may account partially for the decrement in chemosensory capacity in AD patients.

Aged↗

Contribution of Lp(a) to the occurrence of vascular diseases: correlation of several risk factors including diabetes mellitus.

We demonstrated that Lp(a) levels in patients with arteriosclerosis obliterans (21.4 +/- 2.5 mg/dl) and in patients with ischemic heart disease (17.2 +/- 0.8 mg/dl) are higher than those in controls (15.4 +/- 0.7 mg/dl) or healthy controls (11.3 +/- 1.1 mg/dl). Lp(a) levels in patients with these vascular diseases were especially higher when there were known atherosclerotic risk factors such as diabetes mellitus, hypercholesterolemia or hypertension, although Lp(a) levels in patients with these risk-positive group was not different from that of control. These results suggest that Lp(a) contributes to the development of atherosclerotic vascular diseases especially when known atherosclerotic risk factors are not present. We also investigated the case of thromboangiitis obliterans, which is believed to develop from nonatherosclerotic mechanisms, and found that Lp(a) levels were higher (26.5 +/- 9.6 mg/dl) in such patients.

Adult↗

Differential Na+,K(+)-ATPase activity and cisplatin sensitivity between transformants induced by H-ras and those induced by K-ras.

We examined the differential effects of the H-ras oncogene and the K-ras oncogene on cisplatin sensitivity in murine NIH/3T3 cells transfected with these oncogenes. Although the NIH/3T3 cells transformed with H-ras oncogenes (EJ-NIH/3T3 and Ha8-21) showed an increased resistance to cisplatin compared to the parental NIH/3T3, the cell lines transformed with K-ras oncogenes (DT and 1,8DNP2-2-5) did not. Compared with NIH/3T3, the 2 H-ras transformants reduced both the accumulation of cisplatin and the Na+,K(+)-ATPase activity in the membrane fraction. On the other hand, we observed no significant difference in cellular accumulation of cisplatin or in Na+,K(+)-ATPase activity between parental NIH/3T3 and the K-ras transformants. Since these ras transformants did not affect the cellular metallothionein content, transcriptional level of DNA polymerase beta or activity of glutathione-S-transferase which is not associated with cisplatin sensitivity, these results suggest that cisplatin resistance is brought about by the H-ras oncogene, but not by K-ras, and that induction of cisplatin resistance by H-ras is mainly due to a reduction of cisplatin accumulation and an impairment of Na+,K(+)-ATPase activity in the membrane fraction.

3T3 Cells↗

Differential development of binding sites of two lectins in the vomeronasal axons of the rat accessory olfactory bulb.

Binding of fluorochrome-conjugated lectins, Bandeiraea simplicifolia lectin-I (BSL-I) and Vicia villosa agglutinin (VVA), to the vomeronasal axons was investigated in the accessory olfactory bulb (AOB) of developing rats at embryonic day (E) 16, 18, and 20, and postnatal day (P) 0, 3, 7, 14, and 28. Intense fluorescence for VVA was first observed at E18, and the position-specific binding pattern observed in adults was established at P0; intense fluorescence for VVA was observed in the posterior 2/3 of the vomeronasal nerve layer (VNL) and glomerular layer (GL) and weak fluorescence was present in the anterior 1/3 of these layers. Fluorescence for BSL-I was observed in the posterior half of VNL and GL at P0; the area bound with BSL-I was expanded to the anterior area and intensity of the fluorescence increased as the development proceeded. At P28, binding of BSL-I was observed in the entire VNL and GL as identical to adults. These results indicate that the binding sites of BSL-I and VVA in the vomeronasal axons at the level of rat AOB develop differentially during ontogeny, suggesting that rat VN axons consist of two subpopulations expressing different glycoconjugates.

Animals↗

Microscopic structure of the olfactory organ of the clearnose skate, Raja eglanteria.

The olfactory organ of juvenile clearnose skates (Raja eglanteria) was studied with the light and electron microscopes. The organ is ovoid in shape, and its free surface is complicated by the presence of some 20 lamellae. Each lamella has a folded surface lined by a typical neurosensory olfactory epithelium. Bipolar olfactory receptor neurons, ciliated sustentacular cells, and basal cells are the pre-eminent cellular components of the epithelium. Two types of receptor neurons, both bearing microvilli but not cilia, were identified. The type 1 neuron is similar to that previously described in other fishes. The type 2 neuron has a characteristic morphology justifying a separate description. Its dendritic knob is larger than that of type 1, and its microvilli, which are shorter and thicker, are straight and regularly arranged. Tight bundles of filaments provide a skeleton to each microvillus, and these filament bundles reach more than 5 microns down into the dendrite. Type 2 receptor neurons have a well-developed Golgi complex and sparse rough endoplasmic reticulum (rER), whereas type 1 receptor neurons have a less well-developed Golgi complex and a conspicuous system of rER lamellae. The mucous layer on the epithelial surface is provided by the secretion of goblet cells that are situated mostly in the peripheral regions of each lamella. Secretory granules in the sustentacular cells and glands in the lamina propria were not observed.

Animals↗

Lectin histochemical localization of galactose, N-acetylgalactosamine, and N-acetylglucosamine in glycoconjugates of the rat vomeronasal organ, with comparison to the olfactory and septal mucosae.

The localization of alpha-D-galactose, N-acetyl-D-galactosamine, and N-acetyl-D-glucosamine sugar residues of glycoconjugates in the vomeronasal organ, olfactory mucosa, and septal organ in the nasal mucosae of rats was investigated using lectinohistochemical techniques combined with bright-field, epifluorescence, and confocal laser scanning microscopy. Glycoconjugates in the mucomicrovillar complex of the vomeronasal organ contained all the sugar residues investigated, whereas glycoconjugates in the mucociliary complex of the olfactory mucosa and septal organ contained only N-acetyl-D-glucosamine. Vomeronasal receptor neurons expressed glycoconjugates with terminal alpha-D-galactose and beta-N-acetyl-D-galactosamine, and N-acetyl-D-glucosamine residues, whereas olfactory and septal receptor neurons expressed glycoconjugates with only N-acetyl-D-glucosamine residues. Secretory granules of glands of the vomeronasal organ contained glycoconjugates with terminal alpha-D-galactose and N-acetyl-D-galactosamine, and N-acetyl-D-glucosamine, whereas those of the Bowman's glands and glands of septal organ contained glycoconjugates with only internal N-acetyl-D-glucosamine residues. The results demonstrate that the glycoconjugates expressed by vomeronasal receptor neurons and glands contain terminal alpha-D-galactose and beta-N-acetyl-D-galactosamine sugar residues that are not expressed by analogous cells in the olfactory mucosa and septal organ.

Acetylgalactosamine↗

Regulation of hepatocyte albumin and alpha 1-acid glycoprotein secretion by monokines, dexamethasone, and nitric oxide synthase pathway: significance of activated liver nonparenchymal cells.

To clarify the mechanism involved in regulating the secretion of albumin and alpha 1-acid glycoprotein by rat hepatocytes, we studied hepatocyte culture and cocultures of hepatocyte and liver nonparenchymal cells. The secretion of alpha 1-acid glycoprotein by hepatocytes was stimulated and that of albumin was inhibited by combinations of dexamethasone and monokines, especially by dexamethasone and interleukin-6. The secretion of these proteins was equally inhibited during stimulation by lipopolysaccharide in cocultures. The inhibitory effect of sinusoidal endothelial cells was smaller than that of Kupffer cells. This inhibition was partially abolished by blocking the nitric oxide synthase pathway in cocultured cells and was completely abolished by dexamethasone. In conclusion, the secretion of albumin and alpha 1-acid glycoprotein by hepatocytes was regulated by monokines, dexamethasone, and the inducible nitric oxide synthase pathway in hepatocytes and liver nonparenchymal cells in vitro.

Albumins↗

Morphological alterations of gap junctions in phalloidin-treated rat livers.

Morphological alterations in the pattern of liver cell gap junctions were examined in phalloidin-treated rats to assess the role of gap junctions in experimental intrahepatic cholestasis. Double-labelled fluorescent staining of gap junctions and F-actin were performed using a monoclonal antibody against rat hepatocyte connexin 32 and rhodamine-phalloidin. Immunoelectron microscopy, using the anti-connexin 32 antibody, freeze-fracture replica electron microscopy, and conventional electron microscopy were also performed. In phalloidin-treated rat livers, the specific immunofluorescent staining of connexin 32 was markedly decreased in the pericentral area after 1 day of phalloidin treatment and, after 5 days of phalloidin treatment, there was a decrease in connexin 32 staining in the entire hepatic lobule. On the other hand, F-actin staining at the cell periphery and at the bile canaliculi was markedly increased in the pericentral area of the hepatic lobule after 1 day of phalloidin treatment and in the entire lobule after 5 days of treatment. Immunoelectron microscopy showed that both sides of the cytoplasmic domains of gap junctions were stained with anti-connexin 32 antibody in controls, whereas, in cholestatic rats, only one side of the cytoplasmic domain of some gap junctions was stained with anti-connexin 32 antibody after 1 or 3 days of phalloidin treatment. No gap junctions were observed after 5 days of phalloidin treatment either by freeze-fracture replica electron microscopy or by conventional electron microscopy. These results indicate that with phalloidin treatment, hepatocyte gap junctions decrease, first in the pericentral area, and finally throughout the entire lobule.

Actins↗

Hemodynamic effects of combined treatment with somatostatin analogue (SMS 201-995) and low-dose isosorbide dinitrate on portal hypertension in conscious cirrhotic rats.

The authors investigated whether combined treatment with the somatostatin analogue, SMS 201-995, and low-dose isosorbide dinitrate enhanced the hemodynamic effects of the individual agents on rats with thioacetamide-induced cirrhosis. Four groups of cirrhotic rats received SMS 201-995 (0.1 microgram.min-1.kg-1), isosorbide dinitrate (10 micrograms.min-1.kg-1), both agents, or placebo, respectively. Hemodynamics were measured serially in conscious rats, using a radioactive microsphere method. SMS 201-995 reduced portal venous inflow 21 +/- 4% and portal pressure 17 +/- 3%. Isosorbide dinitrate decreased portal venous inflow 20 +/- 4%, by inducing splanchnic vasoconstriction mediated by low pressure baroreflexes, and this agent also decreased portal pressure, by 14 +/- 2%. Portal venous resistance rose 7.6 +/- 3% with isosorbide dinitrate alone, but decreased 18 +/- 4% with combination therapy. This effect may have been induced by the pronounced vasodilatory effect of isosorbide dinitrate on the venous vasculature, since the reflex splanchnic vasoconstriction that occurs with low-dose isosorbide dinitrate disappears when this agent is combined with SMS 201-995. The decrease in portal pressure was more marked (22 +/- 4%) and changes in systemic hemodynamics were milder with the combined treatment. It was concluded that combination therapy with SMS 201-995 and low-dose isosorbide dinitrate may be beneficial for portal hypertension in liver cirrhosis.

Analysis of Variance↗

Human taste cells express the G protein alpha-gustducin and neuron-specific enolase.

Expression of the alpha-subunit of the taste-specific G protein alpha-gustducin and the glycolytic enzyme neuron-specific enolase (NSE) was investigated immunohistochemically in human circumvallate and foliate taste papillae. Immunofluorescence for alpha-gustducin was observed in taste cells of both types of papillae and exhibited two patterns of immunofluorescence, plasmalemmal and cytosolic. The plasmalemmal pattern showed intense immunofluorescence localized to the apical region, and was exhibited by most immunoreactive taste cells. In contrast, the cytosolic pattern, observed in one or two immunoreactive cells in a taste bud per section, showed immunofluorescence distributed throughout the cytoplasm. A subpopulation of alpha-gustducin-immunoreactive taste receptor cells, most of which exhibited the cytosolic pattern, also expressed NSE. Optical sectioning, using confocal laser scanning microscopy, demonstrated the highest level of expression of alpha-gustducin in the apical microvillar region of the taste cells in close apposition to the taste pore. These studies indicate conservation of epitopes of alpha-gustducin in humans and rats, and suggest that this G protein is associated with taste transduction in both rats and humans. The patterns of expression of alpha-gustducin, and coexpression with NSE, may correlate with specialized subtypes or developmental stages of taste receptor cells.

Aged↗

[Side effects of interferon on endocrine and respiratory system in 545 cases of chronic hepatitis C].

We investigated the side effects of interferon (IFN) on the endocrine and respiratory system in 545 cases of chronic hepatitis C. Eleven of 494 (2.2%) patients with chronic hepatitis C who were treated with natural or recombinant interferon (IFN) developed thyroid disease while on treatment. Eight patients developed hyperthyroidism and 3 patients developed hypothyroidism. All 11 patients required definitive therapy, who became euthyroid after the therapy. Two patients received nIFN alpha and one patient received rIFN alpha 2b developed diabetes mellitus. Two patients received rIFN alpha 2a and rIFN alpha 2b, respectively, developed interstitial pneumonia 12 weeks and 24 weeks later, respectively. One patient showed positive reaction for RA test and LE factor and positive LE cell, and complained of fever, arthralgia and dry cough. These phenomenon disappeared after the cessation of IFN therapy.

Adult↗

Genetic heterogeneity of Helicobacter pylori by pulse-field gel electrophoresis and re-evaluation of DNA homology.

PURPOSE: The genetic heterogeneity of Helicobacter pylori isolates was re-evaluated by using pulse-field gel electrophoresis to examine macrorestriction patterns and by studying DNA homology. MATERIALS AND METHODS: Twenty H. pylori isolates, two closely related species, H. mustelae and H. felis, and Campylobacter spp. were used. Notl-digested macrorestriction patterns were examined by pulse-field gel electrophoresis. DNA homology was examined by the S1 nuclease method, using [3H]-labeled DNA from H. pylori NCTC11637 and two H. pylori isolates for reference. RESULT: Intergenus DNA homology between H. pylori and Campylobacters was 50-60%. Interspecies homology between H. pylori and H. mustelae or H. felis was around 60%. Intraspecies homology among H. pylori isolates was above 80%, except for a few that exhibited 70-80% homology. These findings indicate that all H. pylori isolates were homogeneous and belonged to the same species. Notl pulse-field gel electrophoresis patterns of H. pylori isolates differed markedly at the individual strain level. There was no specific relationship to any deviation from DNA homology, and the differences were observed within rather homogeneous members of the species. CONCLUSION: The polymorphism in the Notl pulse-field gel electrophoresis patterns of H. pylori isolates differed markedly among strains, even though these isolates displayed species homogeneity, with DNA homology of 70-100%.

Campylobacter↗