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Biomedical subjects

S Minami

Publications and source records attributed to S Minami.

At least 19 recordsLinked to original sources

Proviral status of HTLV-1 integrated into the host genomic DNA of adult T-cell leukemia cells.

Human T-cell leukemia virus type-1 (HTLV-1) is the etiological agent of adult T-cell leukemia (ATL), and leukemic cells always carry the proviral genome monoclonally integrated into their host genomes at the same sequence site, designated as the monoclonal integration. Using Southern blot hybridization (SBH) and sequenced tagged site polymerase chain reaction assays, we examined the proviral status in 558 clinical specimens from 350 patients who are suspected to have ATL. A total of 321 specimens (57.5%) from 241 patients showed positive results for the monoclonal integration according to SBH, using EcoR1 and Pst1. The 241 patients consisted of 136 patients (56.4%) with the complete provirus (C-type), 62 patients (25.7%) with a defective provirus (D-type), and 43 patients (17.8%) with multibands (M-type). The incidence of the D- and M-types were in the order of smoldering, chronic, and acute subtypes of ATL, suggesting that such an aberrant proviral status is generated on the way to multistep carcinogenesis and is subsequently clinically important for the malignant behavior of the disease. Moreover, our data showed that the partial deletion of the proviral genome is initiated first at the site of the gag region and spreads into the sites of the pol and env regions, whereas the long terminal repeats and pX regions are almost always conserved. These results suggest that analysis of the proviral status provides useful diagnostic and virologic-oncological information about ATL and HTLV-1 pathology, especially the important role of pX gene in tumorigenesis.

Adult↗

Hypernuclear fine structure in (16)(Lambda)O and the LambdaN tensor interaction.

We have observed two gamma-ray transitions in (16)(Lambda)O from the 6.6 MeV excited 1(-)(2) state to both ground-state spin-doublet members (1(-)(1),0(-)) by the (K-,pi(-)gamma) reaction. We have obtained the ground-state doublet spacing to be 26.4+/-1.6(stat)+/-0.5(syst) keV and the excitation energy of the 1(-)(2) state to be 6561.7+/-1.1(stat)+/-1.7(syst) keV. The ground-state doublet spacing provides a small but nonzero strength of the tensor interaction between a Lambda and a nucleon. This is the first experimental result on the LambdaN tensor interaction.

Journal Article↗

Recovery, morphological quality, and in vitro maturation of follicular oocytes from bitches with pyometra.

The objective of this study was to collect oocytes from ovaries of bitches with pyometra and to characterize the quality of the oocytes recovered. In 10 of 12 cases of pyometra, follicles with a diameter of 500 microm to 1mm were observed in the ovaries. A total of 710 oocytes were collected from 10 bitches by puncturing individual follicles after slicing the ovarian tissues. Oocyte recovery was successful from a bitch with severe clinical signs of pyometra. Of the oocytes collected, 53.5% were surrounded by > or =2 layers of cumulus cells, and 55.0% of these cumulus-oocyte complexes (COCs) had a darkly pigmented ooplasm >110 microm in diameter (large-dark COCs). The number of large-dark COCs per bitch varied from 1 to 72. A germinal vesicle with fine filaments of chromatin (Type A) was observed in 51.8% (range 21.1-100%) of the oocytes of large-dark COCs. Out of 50 oocytes cultured for 72 h, 6.0% developed to Metaphase II. In conclusion, there were many follicles with a diameter of 500 microm to 1mm in ovaries of bitches with pyometra, and many oocytes recovered from these follicles underwent meiotic maturation in vitro. The number of oocytes and COCs, and the morphological quality of the germinal vesicles varied among individual bitches.

Animals↗

Rotation of the spinal cord in idiopathic scoliosis.

We undertook a radiographic analysis with pre-operative computed tomographic myelography in 78 patients with idiopathic scoliosis in order to analyse rotation of the spinal cord and to investigate its clinical significance. The angle of rotation of the cord had a statistically significant relationship to both that of the apical vertebra and the size of the primary curve. The relationship between the rotation of the cord and that of the apical vertebra was divided into three types. The cord rotated in the same direction as the apical vertebra in 55 patients and rotated in the opposite direction in the remaining 23 patients. In the first group, the angle of rotation of the cord was more than that of the vertebra in six patients, but less than it in 49 patients. These results suggest that the neuraxis in idiopathic scoliosis may be under tension in the axial dimension.

Adolescent↗

Effects of cilostazol on serum lipid concentrations and plasma fatty acid composition in type 2 diabetic patients with peripheral vascular disease.

Cilostazol is an anti-thrombotic and vasodilating agent, reported to have both anti-thrombotic and cerebral vasodilating effects. We investigated the effects of cilostazol on serum lipid concentrations and plasma fatty acid composition in type 2 diabetic patients with peripheral vascular disease. The serum concentrations of total cholesterol, triglycerides, high-density lipoprotein-cholesterol, lipoprotein (a), remnant-like particles-cholesterol, apolipoproteins, and plasma fatty acid composition were measured in 17 diabetic patients with peripheral vascular disease before and 1, 3, and 6 months after administration of cilostazol (200 mg/day). Serum triglyceride concentrations were significantly decreased after cilostazol (from 1.31+/-0.17 mmol/l to 0.86+/-0.07 mmol/l at 6 months, P<0.01). Plasma docosahexaenoic acid levels were significantly increased after cilostazol (4.11+/-0.26% to 4.94+/-0.26% at 6 months, P<0.01). Our findings show that cilostazol can induce some beneficial changes in serum lipid profile and plasma fatty acid composition.

Aged↗

Significance of HTLV-1 proviral load quantification by real-time PCR as a surrogate marker for HTLV-1-infected cell count.

We developed a real-time (RT) PCR quantitative assay to measure the level of the integrated viral genome of HTLV-1 in host peripheral blood-mononuclear cells (PB-MNC) from healthy carriers and patients with adult T-cell leukemia (ATL). All of the clinical specimens were serologically and molecularly characterized by enzyme-linked immunosorbent assay (ELISA) and Southern blot hybridization (SBH) analyses. The assay system for quantifying the proviral copy level was sensitive, accurate, and reproducible over a wide range of density from 100 to 0.1% with a coefficient of variation (%) of 4.5 to 9.6. The proviral load of the healthy carriers and patients with ATL was 301 +/- 339 copies per 10(4) MNC (3 +/- 3.4%) on average and varied depending on the ATL cell number and the SBH band-status of single or multiple bands. In ATL cases with multiple bands detected by SBH analysis, their ATL cells were shown to harbor multiple copies within one ATL cell, so that the corrected copy number interpolated by the band number in SBH was closely equivalent to the expected ATL cell number in PB, corresponding to the virus-infected cell burden. The proviral load in healthy carriers ranged from 0.1 to 15% of PB-MNC, and, in combination with the fraction (%) of ATL-like flower cells defined by PB smear morphology, enabled carriers to be subgrouped into three categories. This result indicates that the detection of proviral load by(RT) PCR is sufficient and relevant to monitor the infected cell number in the PB and to evaluate the HTLV-1 pathologic status.

Biomarkers↗

Corticotropin-releasing factor type-1 receptor mRNA is not induced in mouse hypothalamus by either stress or osmotic stimulation.

In rats, acute stress substantially increases corticotropin-releasing factor (CRF) type 1 receptor (CRFR-1) mRNA expression in the paraventricular nucleus (PVN) and osmotic stimulation induces both CRF and CRFR-1 mRNA in magnocellular PVN and supraoptic nucleus (SON). However, these phenomena have not been analysed in other species. We compared CRF and CRFR-1 expression in rat and mouse hypothalamus. Male C57BL/6 mice and Wistar rats were exposed to acute restraint stress for 3 h, or to hypertonic saline ingestion for 7 days. Restraint stress increased CRF and c-fos mRNA expression in both rat and mouse PVN. CRFR-1 mRNA was barely detectable in controls, whereas restraint stress substantially increased CRFR-1 mRNA in rat PVN, but not in mouse. Hypertonic saline ingestion induced CRF mRNA in magnocellular PVN and SON of the rat, but did not alter CRF mRNA levels in mouse hypothalamus. CRFR-1 mRNA was also induced in magnocellular PVN and SON of the rat in response to osmotic stimulation, but not in mouse. Immunohistochemistry demonstrated that CRFR-1-like immunoreactivity (ir) was distributed within parvocellular and magnocellular PVN of mouse and rat. CRFR-1-ir in rat PVN was increased by acute stress and osmotic stimulation. By contrast, these treatments did not alter CRFR-1-ir in mouse PVN. Combined immunohistochemistry and in situ hybridization revealed that CRFR-1-ir was most frequently colocalized to CRF in mouse PVN, whereas only a small percentage of oxytocin and vasopressin-producing cells coexpressed CRFR-1-ir. These results indicate that (i) by contrast to rats, neither acute stress nor osmotic stimulation induces CRFR-1 mRNA expression in the mouse PVN; (ii) osmotic stimulation does not alter CRF mRNA expression in parvocellular and magnocellular neurones of mouse PVN; and (iii) acute stress increases c-fos and CRF mRNA to a similar degree in mouse and rat PVN. Thus, differences may exist between mouse and rat in the regulation of CRF and CRFR-1 gene expression in hypothalamus following stress and osmotic stimulation.

Animals↗

In vitro and in vivo activities of anti-influenza virus compound T-705.

T-705 (6-fluoro-3-hydroxy-2-pyrazinecarboxamide) has been found to have potent and selective inhibitory activity against influenza virus. In an in vitro plaque reduction assay, T-705 showed potent inhibitory activity against influenza A, B, and C viruses, with 50% inhibitory concentrations (IC(50)s) of 0.013 to 0.48 microg/ml, while it showed no cytotoxicity at concentrations up to 1,000 microg/ml in Madin-Darby canine kidney cells. The selectivity index for influenza virus was more than 2,000. It was also active against a neuraminidase inhibitor-resistant virus and some amantadine-resistant viruses. T-705 showed weak activity against non-influenza virus RNA viruses, with the IC(50)s being higher for non-influenza virus RNA viruses than for influenza virus, and it had no activity against DNA viruses. Orally administered T-705 at 100 mg/kg of body weight/day (four times a day) for 5 days significantly reduced the mean pulmonary virus yields and the rate of mortality in mice infected with influenza virus A/PR/8/34 (3 x 10(2) PFU). These results suggest that T-705 may be a compound that is useful and highly selective against influenza virus infections and that has a mode of action different from those of commercially available drugs, such as amantadine, rimantadine, and neuraminidase inhibitors.

Amides↗

Production of (4)(double Lambda)H hypernuclei.

An experiment demonstrating the production of double-Lambda hypernuclei in (K(-),K(+)) reactions on (9)Be was carried out at the D6 line in the BNL alternating-gradient synchrotron. The technique was the observation of pions produced in sequential mesonic weak decay, each pion associated with one unit of strangeness change. The results indicate the production of a significant number of the double hypernucleus (4)(double Lambda)H and the twin hypernuclei (4)(Lambda)H and (3)(Lambda)H. The relevant decay chains are discussed and a simple model of the production mechanism is presented. An implication of this experiment is that the existence of an S = -2 dibaryon more than a few MeV below the double Lambda mass is unlikely.

Journal Article↗

Observation of spin-orbit splitting in lambda single-particle states.

The spin-orbit splitting of Lambda single-particle states in (13)(Lambda)C was measured. The 13C(K-,pi(-))(13)(Lambda)C reaction was used to excite both the 1/2(-) and 3/2(-) states simultaneously, which have predominantly 12C(0(+)) x p(Lambda) configuration. gamma rays from the states to the ground state were measured in coincidence with the pi(-)'s, by which ls splitting was found to be 152+/-54(stat)+/-36(syst) keV. The value is 20-30 times smaller than exhibited by the ls splitting in the nuclear shell model. This value gives us new insight into the YN interaction.

Journal Article↗

Role of carcinoembryonic antigen in the progression of colon cancer cells that express carbohydrate antigen.

Carcinoembryonic antigen (CEA) has been reported to promote the metastatic potential in some experimental tumors. Adhesion molecules are known to play an important role in the process of metastasis. Cytokines, including interleukin 1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha), which are produced by Kupffer cells, induce endothelial cells to express adhesion molecules. As a result, the present study was designed to investigate whether the interaction between CEA and Kupffer cells accelerated the metastatic potential of tumors in the liver. Kupffer cells isolated from the liver of male BALB/c mice were cultured with CEA, either with or without the addition of a cytokine inhibitor. The levels of IL-1beta and TNF-alpha were examined in a culture medium. An adhesion assay of colon cancer cell lines to human umbilical vein endothelial cells was also performed. When CEA was added to the Kupffer cell culture medium, cytokines were produced. Elevated levels of cytokines appeared to lead to increased rates of adhesion of cancer cells to endothelial cells. However, these phenomena were blocked by the addition of cytokine inhibitors. CEA stimulated Kupffer cells to produce cytokines. An elevated number of cytokines have been proven to promote the expression of adhesion molecules in endothelial cells. These processes are therefore considered to contribute to the metastasis of malignant cells to the liver. These results suggest that cytokine inhibitors may therefore play an important role in the inhibition of hepatic metastasis.

Animals↗

Selective inhibition of nicotinic cholinergic receptors by proadrenomedullin N-terminal 12 peptide in bovine adrenal chromaffin cells.

We studied whether a novel proadrenomedullin derived peptide was present and what was its physiological function in cultured bovine adrenal chromaffin cells. We found a high level of proadrenomedullin N-terminal 12 peptide (PAMP-12) which consists of a peptide from 9th amino acid to 20th amino acid of proadrenomedullin N-terminal 20 peptide (PAMP-20). PAMP-12 was released from the cells along with catecholamine upon stimulation of nicotinic cholinergic receptors. When PAMP-12 was added in the incubation medium, this peptide inhibited nicotinic receptor-mediated catecholamine release and influx of Na(+) and Ca(2+) into the cells. PAMP-12 did not affect catecholamine release evoked by histamine or by depolarization by high concentration of potassium. PAMP-12 also inhibited synthesis of catecholamines as well as the activation of tyrosine hydroxylase by nicotinic stimulation. Thus, PAMP-12 is an endogenous peptide that regulates release and synthesis of catecholamines by acting on nicotinic cholinergic receptors in an autocrine manner in adrenal chromaffin cells.

Adrenal Medulla↗

Aquaporin subtypes in rat cerebral microvessels.

We investigated the expression of aquaporin (AQP) subtypes in the rat cerebral microvessels by reverse transcription-polymerase chain reaction, immunoblotting and immunohistochemistry. mRNA for AQP4, but not for AQP1, 2, 3 or 5, was detected in the microvessels. Immunoblot analysis showed that AQP4 protein was detected as a 30 kDa band with higher molecular weight bands. Immunohistochemical staining showed that AQP4 was located on cell surface of the cerebral microvessels. These results suggest that AQP4 in the cerebral microvessels is involved in the regulation of water transport between blood and brain.

Animals↗

Adrenomedullin receptors in rat choroid plexus.

To characterize transmembrane signaling of adrenomedullin (AM) in the choroid plexus, we studied the effects of AM on cyclic AMP (cAMP) and cyclic GMP (cGMP) levels as well as expression of mRNA for AM receptor in the rat choroid plexus slices. AM or calcitonin gene-related peptide (CGRP) increased cAMP (but not cGMP) level in a concentration-dependent manner, with AM being much more potently than CGRP. AM mRNA as well as calcitonin-receptor-like receptor mRNA and receptor-activity-modifying protein 2 mRNA, were highly expressed in the choroid plexus. Our biochemical and pharmacological studies may raise the possibility that choroid plexus secretes AM into the cerebrospinal fluid, and AM regulates choroid plexus function in an autocrine/paracrine manner via acting on AM-specific receptors.

Adrenomedullin↗

Production of activin A in hyperplasia and adenocarcinoma of the human endometrium.

OBJECTIVES: To examine the possible localization and production of activin A in human normal endometrium, endometrial hyperplasia, and adenocarcinoma tissues. METHODS: Human endometrial tissues were collected from 45 patients who were undergoing abdominal hysterectomy. Tissue sections were stained with monoclonal antibodies against the inhibin/activin alpha- and beta A-subunits and activin A using an avidin-biotin-peroxidase complex technique. Concentrations of activin A and inhibin A in tissue extracts of the endometrial tissues were measured using enzyme-linked immunosorbent assays (ELISAs). The expressions of the inhibin alpha-subunit and activin beta A-subunit messenger RNA (mRNA) in the endometrial tissues were demonstrated by reverse transcription-polymerase chain reaction (RT-PCR) analysis. RESULTS: No immunostaining with an antibody against the inhibin alpha-subunit was observed in human normal endometrium, endometrial hyperplasia, and adenocarcinoma. By contrast, immunostaining for the activin beta A-subunit and activin A was observed in the cytoplasm of glandular cells in normal endometrium, endometrial hyperplasia, and tumor cells of endometrial adenocarcinoma. The percentages of stained cells in endometrial adenocarcinoma were higher than those in normal endometrium. Also, the percentages of stained tumor cells with poor differentiation were higher than those with good and moderate differentiation of the endometrium. The stromal cells in normal endometrium, endometrial hyperplasia, and adenocarcinoma were weakly immunoreactive with antibodies against the beta A-subunit and activin A. Immunoreactivity of activin A in tissue extracts from normal endometrium and endometrial adenocarcinoma was detected by the two-site ELISA. Immunoreactivity of activin A was significantly higher in adenocarcinoma than in normal endometrium. On the other hand, the immunoreactive inhibin A was not detected. The expression of the alpha-subunit mRNA in endometrial tissues was demonstrated as the RT-PCR products migrated at 905 bp and the PCR products of the beta A-subunit showed a band at 366 bp. CONCLUSIONS: It is suggested that activin A, but not inhibins, are produced by endometrial tissues. The amounts of produced activin A were higher in adenocarcinoma tissues than in normal endometrium. Activin A might be involved in human endometrial tumorigenesis.

Activins↗

Selective expression of aquaporin 1, 4 and 5 in the rat middle ear.

The middle ear cavity is an air-filled space that must be maintained for effective sound transmission to the inner ear. To examine the mechanisms of water homeostasis in the middle ear, we investigated whether aquaporins (AQPs), a family of water-permeable channels, were expressed in the middle ear. Reverse transcription-polymerase chain reaction and immunoblot analyses revealed that mRNAs encoding AQP1, 4 and 5 (but not 2 or 3) subtypes were expressed in rat middle ear epithelium; AQP1, 4 and 5 were detected as 28-, 30- and 30-kDa proteins, respectively. Immunohistochemical analysis showed that AQP1 was localized at capillary endothelial cells and fibroblasts in lamina propria mucosae; AQP4 was present solely at the basolateral membrane of ciliated cells, whereas AQP5 was on the apical surface of ciliated cells as well as of flat and columnar epithelial cells. The characteristic different localizations of AQP1, 4 and 5 subtypes in the middle ear suggest that middle ear water homeostasis requires the coordinated operation of these AQPs.

Animals↗

Enzymatic determination of acetylcarnitine for diagnostic applications.

An enzymatic method was proposed for determination of acetylcarnitine (AcCar), even when carnitine (Car), non-acetylated form, co-exists. The method is consisted of four enzymatic reactions: First, AcCar is hydrolysed by acylcarnitine hydrolase to yield acetate; followed by the other three reactions coupled with three enzymes, respectively, acetate kinase, pyruvate kinase and lactate dehydrogenase; finally, the acetate formation causes a decrease in NADH. The amount of AcCar is then evaluated as the change in absorbance at 340 nm. The reagent composition of the reaction mixture was determined, and the characteristics of the method were investigated. The dilution test showed a good linearity over a wide range. The precision and accuracy tests produced satisfactory results. The co-existence of Car gave no effect on the measurement. The present method was found to be used easily, simply and rapidly for the selective determination of AcCar.

Acetylcarnitine↗