Search PubMed⌕ Search

Biomedical subjects

M Hattori

Publications and source records attributed to M Hattori.

At least 127 records · Page 7Linked to original sources
PubMed2000

Inhibition of human immunodeficiency virus type 1 reverse transcriptase and ribonuclease H activities by constituents of Juglans mandshurica.

From the stem-bark of Juglans mandshurica, two new naphthalenyl glucopyranosides, 1,4,8-trihydroxynaphthalene 1-O-[alpha-L-arabinofuranosyl-(1-->6)-beta-D-glucopyranoside] (1) and 1,4,8-trihydroxynaphthalene 1-O-beta-D-[6'-O-(3",5"-dihydroxy-4"-methoxybenzoyl)]glucopyranosi de (4), and two new alpha-tetralonyl glucopyranosides, 4 alpha,5,8-trihydroxy-alpha-tetralone 5-O-beta-D-[6'-O-(3",5"-dihydroxy-4"-methoxybenzoyl)]glucopyranosi de (7) and 4 alpha,5,8-trihydroxy-alpha-tetralone 5-O-beta-D-[6'-O-(3",4",5"-trihydroxybenzoyl)]glucopyranoside (8), were isolated together with three known naphthalenyl glucopyranosides (2, 3 and 5), one alpha-tetralonyl glucopyranoside (6), four flavonoids (9-12), and two galloyl glucopyranosides (13, 14). Amongst the isolated compounds, 1,2,6-trigalloylglucopyranose (13) and 1,2,3,6-tertagalloylglucopyranose (14) exhibited the most potent inhibition of reverse transcriptase (RT) activity with IC50 values of 0.067 and 0.040 microM, respectively, while the latter compound also inhibited ribonuclease H (RNase H) activity with an IC50 of 39 microM, comparable in potency to illimaquinone used as a positive control. 1,4,8-Trihydroxy-naphthalene 1-O-beta-D-glucopyranoside (2), 1,4,8-trihydroxynaphthalene 1-O-beta-D-[6'-O-(4"-hydroxy-3",5"-dimethoxybenzoyl)]glucopyranoside (3) and 8 showed moderate inhibition against both enzyme activities, and inhibitory potency of 2 against RNase H activity (IC50 = 156 microM) was slightly greater than that against the RT activity (IC50 = 290 microM). The inhibitory potencies of 4 alpha,5,8-trihydroxy-alpha-tetralone 5-O-beta-D-[6'-O-(4"-hydroxy-3",5"-dimethoxybenzoyl)] glucopyranoside (6), 7 and 8 against RT activity increased accompanied by an increase in the number of free hydroxyls on the galloyl residues, as represented by the IC50 values of > 500, 330 and 5.8 microM, respectively.

Chromatography, Liquid↗
PubMed2000

Four new saponins from the root bark of Aralia elata.

Four new saponins, 3-O-[beta-D-glucopyranosyl(1-->3)-alpha-L-arabinopyranosyl]-16a lpha-hydroxyoleanolic acid 28-O-beta-D-glucopyranosyl ester (called aralia-saponin I), 3-O-[beta-D-glucopyranosyl(1-->3)-alpha-L-arabinopyranosyl]-16a lpha-hydroxyhederagenin 28-O-beta-D-glucopyranosyl ester (aralia-saponin II), 3-O-[beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->3)-alpha-L-+ ++arabinopyranosyl]-16alpha-hydroxyoleanolic acid 28-O-beta-D-glucopyranosyl ester (aralia-saponin III), 3-O-[beta-D-glucopyranosyl(1-->3)-beta-D-gucopyranosyl(1-->3)-beta -D-glucucopyranosyl]-16alpha-hydroxyoleanolic acid 28-O-beta-D-glucopyranosyl ester (aralia-saponin IV), were isolated from the root bark of Aralia elata (Miq.) Seem., together with nineteen known compounds including glycosides of (20S)-protopanaxadiol and (20S)-protopanaxatriol. Their structures were determined on the basis of chemical and spectroscopy methods.

Carbohydrate Conformation↗
PubMed2000

Reversible thermal transition of soluble branched chains from slightly acid-treated potato starch.

The reversible thermal transition of soluble branched starch chains prepared from slightly acid-treated potato starch granules (ATS) was investigated. Potato starch was immersed in 15% sulfuric acid to obtain ATS with a 1% hydrolysis rate. About half of the molecules of ATS, which spontaneously formed large aggregates with a mass of a few million daltons in aqueous solution, was fractionated and soluble branched starch chains with a relative molecular weight (Mr) of 8.91 x 10(4) were obtained. Structural analysis indicated that the soluble branched starch chains consisted of three unit chains with Mr 7,900 and 21 unit chains with Mr 2,700. DSC and FT-IR measurements showed that the soluble branched starch chains underwent a reversible thermal transition, which is considered to be a helix-coil transition, during heating and cooling, but a debranched sample and beta-limit dextrins showed substantially different thermal behavior, indicating the contribution of the ordered structure of the branched chains.

Acids↗
PubMed2000

Inhibitory effect of retinoic acid on the development of immature porcine granulosa cells to mature cells.

The present study investigated the effect of retinoic acid (RA) on the differentiation of granulosa cells prepared from porcine ovaries. The granulosa cells were precultured for 15 h, then cultured for 48 h with FSH and further treated for 24 h with LH in order to induce their transformation into luteal cells. After the cells had been exposed to 1 microM retinoids (RA, retinal and retinol) for 87 h, analysis of the LH receptor mRNA expression, an indicator of granulosa cell differentiation, was carried out by using semiquantitative RT-PCR. The results showed that there was a decrease in LH receptor mRNA levels, and that RA had a more potent effect on these levels than the other two retinoids. When cells were exposed to RA in the immature stage (before the addition of FSH) or the early stage of development (0-24 h after the addition of FSH), expression of LH receptor mRNA was greatly diminished. When the immature cells were cultured for 15 h with RA, then washed and cultured for 48 h with FSH and for 24 h with LH, the expression of LH receptor mRNA was not reversed. In the differentiated cells (24 h after the addition of FSH), however, RA no longer had any inhibitory effect. When the immature cells were exposed to RA, FSH-induced expression of c-fos mRNA was markedly decreased. In contrast, expression of c-jun and activating transcription factor-4 mRNAs remained constant. However, the expression of c-fos mRNA was not decreased by forskolin. The results indicate that RA is a potent inhibitor in the immature stage of porcine granulosa cell differentiation, probably through decreased expression of FSH receptor, but that RA does not inhibit differentiation in the mature stage of the cells.

Animals↗
PubMed2000

Influence of finishing on the electrochemical properties of dental alloys.

Dental alloy surface finishing procedures of may influence their electrochemical behavior, which is used to evaluate their corrosion resistance. We examined the polarization resistance and potentiodynamic polarization profile of the precious-metal alloys, Type 4 gold alloy and silver-palladium alloy, and the base-metal alloys, nickel-chromium alloy, cobalt-chromium alloy, and CP-titanium. Three types of finishing procedure were examined: mirror-finishing using 0.05 micron alumina particles, polishing using #600 abrasive paper and sandblasting. Dissolution of the alloy elements in 0.9% NaCl solution was also measured and compared with the electrochemical evaluation. The corrosion resistance of the dental alloys was found to relate to finishing as follows: The polarization resistance and potentiodynamic polarization behavior revealed that the corrosion resistance improved in the order of sandblasting, #600-abrasive-paper polishing, and mirror-finishing. While the corrosion potential, critical current density and passive current density varied depending on the type of finishing, the transpassive potential remained unchanged. The influence of finishing on the corrosion resistance of precious-metal alloys was less significant than on that of base-metal alloys. A mirror-finishing specimen was recommended for use in evaluation of the corrosion resistance of various dental alloys.

Alloys↗
PubMed2000

Predictive factors for central nervous system involvement in non-Hodgkin's lymphoma: significance of very high serum LDH concentrations.

Factors predictive for central nervous system (CNS) involvement at presentation were investigated in 152 patients with non-Hodgkin's lymphoma (NHL) except for lymphoblastic cell lymphoma and small noncleaved cell lymphoma. Twelve patients developed CNS involvement during their disease course. The incidence was 7.9% of all the patients studied and 17.0% of the patients with serum LDH concentration > or = two times the upper limit of normal (2N). By univariate analysis, stage IV disease (P = .023), a serum LDH concentration > or = 2 N (P = .009), and bone marrow involvement (P = .016) were risk factors for CNS involvement. Multivariate logistic regression analysis identified a serum LDH concentration > or = 2 N (P = .032) as an independent predictor for CNS involvement. All 12 patients who developed CNS involvement were among the 126 patients with diffuse lymphoma, whereas none of the 17 patients with follicular lymphoma developed CNS involvement, although the difference was not statistically significant. The median survival of the patients with CNS involvement was only 4.5 months. We conclude that a serum LDH concentration > or = 2N at presentation is a significant predictive factor for CNS involvement for NHL patients without lymphoblastic lymphoma and small noncleaved cell lymphoma. Therefore, we would suggest that CNS prophylaxis should be considered for patients with a serum LDH concentration > or = 2N at presentation and diffuse lymphoma once a complete remission is achieved.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

[A field study of health effects of aircraft noise in adults around Komatsu Air Base (1998)].

OBJECTIVE: To ascertain the effects of aircraft noise on complaints about life disturbances and on psychological and physical symptoms in adults around Komatsu air base. METHODS: From April to June 1998, a questionnaire was answered by 203 persons (from 89.8% of families) in 2 areas without aircraft noise, and by 412 persons (from 89.0% of families) in 5 areas with a weighted equivalent continuous perceived noise level (WECPNL) of 75 or more. The questionnaire covered age, gender, work location, noise exposure time, past experience with noisy work and ear disease, complaints about noisiness and life disturbances, and psychological and physical symptoms. Multivariate linear models by JMP (SAS institute Inc.) were applied to analyze the relationships between the above factors including noise level and complaints or symptoms. RESULTS: Subjects in the areas with noise had more complaints about noisiness than 5 years before, although replies were less in areas without noise. Subjects in areas with a WECPNL of 75 or more had more complaints and symptoms than those in areas without noise. Moreover, subjects experiencing higher noise levels gave higher responses for most of complaints and symptoms. The JMP linear models showed that aircraft noise was positively related to complaints and symptoms after taking the effects of age, gender and past experience with noisy work and ear disease into consideration. Higher noise levels and longer exposure times were related more strongly to most complaints and symptoms. CONCLUSION: This study shows that aircraft noise with a WECPNL of 75 or more is related to various complaints and psychological and physical symptoms in adults around Komatsu air base, after considering the effects of age, gender and past experience with noisy work and ear disease. It also shows that higher noise levels and longer exposure times are related more strongly to many complaints and symptoms. The results also suggest that responses to aircraft noise have become more severe than in the past.

Adult↗
PubMed2000

[Clinical study of 18 pediatric cadaveric renal transplantations: organ sharing in pediatric renal transplantation after enforcement of the organ transplant law in Japan].

Renal transplantation is considered to be the optimal replacement therapy for children with end-stage renal disease. However, the number of pediatric renal transplants in Japan is much lower than in the USA and/or Europe. Since October 1997, pediatric(< 15 years) recipients are given priority over adult recipients for organ sharing, only if one or two HLA-DR antigen(s) are matched between the recipient and pediatric(< 15 years) donor. However, the number of pediatric transplants is not increasing. One hundred and twenty-four pediatric renal transplantations were performed in Tokyo Women's Medical University between 1983 and 1999, of which 18(14.5%) were cadaveric transplants and the others (106, 85.5%) were living-related transplants. We examined 18 pediatric cadaveric renal transplantations. Seven patients received their graft from pediatric donors less than 15 years of age and 11 from adult donors. The mean age at transplantation was 13.2 years (range 4.5-18.7 years). Major etiologies of renal disease are hereditary renal disease(38.8%), chronic glomerulonephritis(33.3%), and focal segmental glomerulosclerosis[FSGS] (16.7%). Zero matches in HLA-DR locus were observed in 72.2%. Patient survival rate was 100%. Graft survival rates at 1 and 5 years after transplantation were 83% and 64% successively. There was no significant difference between the graft survival of cadaveric and living-related transplantation at 1 and 5 years. All 5 patients who received their graft between 1994 and 1998 have maintained normal graft function. Causes of their graft loss were chronic rejection in 3, recurrence of FSGS in 2, primary non-function in 1, and graft thrombosis in 1. Donor age and HLA-DR mismatching did not affect the outcome. We propose that pediatric renal grafts should be provided to children with priority, regardless of their HLA-A, B and HLA-DR matching.

Adolescent↗
PubMed2000

[An autopsy case of corticobasal degeneration without prominent cortical pathology--an imitator of progressive supranuclear palsy].

We describe an autopsy case of parkinsonism with bradykinesia, muscle rigidity, and dementia as major symptoms. The patient had developed bradykinesia at the age of 62, and then muscle rigidity, a parkinsonian posture, bradylalia, and dementia gradually appeared. Neurological examination revealed rigidity in the neck and limbs, with motion and speech being generally slow. He lacked involuntary movements including alien hand, tremor, chorea, and dystonia. Vertical gaze palsy, both upward and downward was noted, but other cranial nerves were intact. He was diagnosed as suffering from PSP clinically based on vertical gaze palsy, bradykinesia, instability on standing and gait, and dementia. Levodopa was only transiently effective. Within three years he became bed-ridden and in a state of akinetic mutism. At age 65 he died from pneumonia. Neuropathology revealed severe neuronal degeneration and gliosis in the substantia nigra. Because atrophy of the tegmentum of brainstem, dentate nuclei, inferior olivary nuclei was very mild and Alzheimer neurofibrillary tangles in the brainstem were relatively few, PSP was ruled out. Cortical neuronal degeneration was not apparent, but in the deep layer of cingulate gyrus, frontal lobe, and insula, there were several ballooned neurons. Gallyas-Braak silver staining showed no tuft-shaped astrocytes, specific for PSP, but it disclosed astrocytic plaques in the basal ganglia and the cerebral cortex. At present, astrocytic plaques are recognized as a hallmark of corticobasal degeneration (CBD), along with ballooned neurons in the cerebral cortex. The present case thus illustrates that CBD has a wide spectrum and may include cases in which degeneration of cerebral cortex is very mild.

Aged↗
PubMed2000

Subjective symptoms acquisition system in a health promotion system for the elderly. Committee of System Development, Council of Japan AMHTS Institutions.

A previous report was concerned with the evaluation of quality of life using a Health Promotion System for the Elderly. In the present report, we describe one part of that system: a subjective symptoms acquisition and reporting system. The main purpose of this system is to permit any physician or nurse to uniformly employ questionnaires to acquire accurate subjective symptoms. This system is applied in three steps. First, the subjective answers to 21 questions displayed on a personal computer are obtained. These answers correspond to the basic subjective symptoms. Second, if a basic subjective symptom is "positive", more detailed questions are automatically generated. Finally, clear sentences regarding subjective symptoms are generated and output as a "finding report". This information is helpful to physicians and nurses in their health-counseling work. An artificial intelligence (AI) program based on "XpertRule" produces detailed questions which are generated by an interactive questionnaire using branching logical rules.

Aged↗
PubMed2000

[Treatment outcome in elderly patients with aggressive non-Hodgkin's lymphoma].

Seventy-one patients aged 61-84 years with previously untreated aggressive non-Hodgkin's lymphoma were treated with a doxorubicin-containing regimen and evaluated retrospectively. The patients comprised 49 men and 22 women with a median age of 68 years. The median observation period was 544 days. Histological examination revealed 17 cases of diffuse small cleaved, 11 cases of diffuse mixed, 40 cases of diffuse large, and 3 cases of immunoblastic lymphoma, classified according to the International Working Formulation. When the patients were divided according to the age-adjusted international index, group A (61-64 years; n = 21) comprised 5 low (L)-, 4 low-intermediate (LI)-, 7 high-intermediate (HI)-, and 5 high (H)-risk patients. The corresponding numbers in group B (> or = 65 years; n = 50) were 14, 12, 16, and 8, respectively. The overall three-year survival rate was 50%, being 78% in group A and 36% in group B (P = 0.02), and 77% for L + LI patients and 34% for HI + H patients (P = 0.003). The respective three-year survival rates for L + LI and HI + H patients were 100% and 67% in group A, and 68% and 16% in group B. HI + H patients in group B showed shorter survival than L + LI patients in group B (P = 0.002) and HI + H patients in group A (P = 0.03). The cause of death in most group B HI + H patients was lymphoma, although the dose intensity of doxorubicin, cyclophosphamide and vincristine did not differ significantly from that in the other groups. Thus, HI + H patients aged 65 and over had an essentially poor prognosis.

Aged↗
PubMed1999

Chromosome of the enterohemorrhagic Escherichia coli O157:H7; comparative analysis with K-12 MG1655 revealed the acquisition of a large amount of foreign DNAs.

A complete Xba I and Bln I cleavage map was constructed for the chromosome of an enterohemorrhagic Escherichia coli (EHEC) O157:H7 strain isolated from an outbreak in Sakai City, Japan, in 1996. A comparative chromosome analysis with E. coli K-12 strain MG1655 was made. The EHEC chromosome was approximately 5600 kb in length, 1 Mb larger than that of MG1655. Despite the marked difference in chromosome length, the location and direction of seven rRNA operons of the EHEC strain were similar to those for MG1655. Overall organization of genes common in both strains is also highly conserved. Chromosome expansion was observed throughout the EHEC chromosome, albeit in an uneven manner. A large portion of the chromosome enlargement was observed in the region surrounding the replication terminus, particularly in a segment containing the terA locus. Sample sequencing of 3627 random shotgun clones suggested the presence of approximately 1550 kb strain-specific DNAs on the EHEC chromosome, most of which are likely to be of foreign origin.

Bacterial Toxins↗
PubMed1999

A 2-Mb sequence-ready contig map and a novel immunoglobulin superfamily gene IGSF4 in the LOH region of chromosome 11q23.2.

Human chromosome 11q23.2 has been proposed to contain a tumor suppressor gene(s) whose deletion has been associated with cancer of the lung and breast and with neuroblastoma. To analyze the genomic structure and to isolate a candidate tumor suppressor gene from this region, we constructed a 2-Mb sequence-ready contig map using bacteriophage P1 (P1), bacterial artificial chromosome (BAC), and P1-derived artificial chromosome (PAC). The map comprises a contig of 24 overlapping P1, BAC, and PAC clones. To isolate gene fragments from the region, we performed direct cDNA library screening, exon trapping, EST mapping, and genomic sequencing using the P1, BAC, and PAC clones. Sequence analysis of 5 clones, which spans 23% (458,738 bp) of the region, and extensive gene scanning along the entire region revealed that the region is extraordinarily scarce in genes, but we identified one ubiquitously expressed novel gene and one testis-specific gene fragment. The novel gene, which we call IGSF4 (immunoglobulin superfamily 4), is transcribed into a 1.6- or 4.4-kb RNA encoding a 442-amino-acid protein. It shares strong homology with mouse IGSF-B12 and cell adhesion molecules NCAM1 and NCAM2 within their Ig-like C2-type domains. The IGSF4 gene, a novel gene that is shown to be located in the common loss of heterozygosity region, possesses a number of interesting features and may be good candidate for a tumor suppressor gene.

Amino Acid Sequence↗
PubMed1999

Role of mast cell chymase in angiotensin-induced vascular contraction of hamster cheek pouch microvessels.

We investigated the contribution of chymase-dependent conversion of angiotensin I to angiotensin II in hamster cheek pouch. To investigate the converting activities in intact tissues, angiotensin I or II was applied to microvessels of the intact cheek pouch, and the vascular contractile response was recorded. Angiotensin I or angiotensin II (20 nM) induced a rapid contraction of arterioles, irrespective of their diameter. In the presence of I mM captopril, there was no contraction in response to angiotensin I in arterioles < 25 microm in diameter, whereas contraction was still observed in larger arterioles. Chymostatin (100 microM) treatment also reduced the response to angiotensin I in arterioles > 40 microm in diameter. Treatment with 1 mM captopril and 100 microM chymostatin resulted in the loss of response to angiotensin I, but not to angiotensin II, in all arterioles. Treatment of microvessels with 100 microg/ml compound 48/80 enhanced angiotensin I-induced vascular contraction response, suggesting the significance of mast cells as a source of cheek pouch chymase.

Angiotensin I↗
PubMed1999

Cutting edge: homologous recombination of the MHC class I K region defines new MHC-linked diabetogenic susceptibility gene(s) in nonobese diabetic mice.

To localize the MHC-linked diabetogenic genes in the nonobese diabetic (NOD) mouse, a recombinational hotspot from the B10.A(R209) mouse was introduced to the region between the MHC class I K and class II A of the NOD mouse with the recombinational site centromeric to the Lmp2/Tap1 complex by breeding the two strains. Replacement of the NOD region centromeric to the recombinational site with the same region in R209 mice prevented the development of diabetes (from 71 to 3%) and insulitis (from 61 to 15%) in the N7 intra-MHC recombinant NOD mice. Similarly, the replacement of the NOD class II A, E and class I D region with the same region in R209 mice prevented the diseases (diabetes, from 71 to 0%; insulitis, from 61 to 3%). In addition to the MHC class II genes, there are at least two MHC-linked diabetogenic genes in the region centromeric to Lmp2.

Animals↗
PubMed1999

Rap1 GTPase-activating protein SPA-1 negatively regulates cell adhesion.

Rap1 GTPase is activated by a variety of stimulations in many types of cells, but its exact functions remain unknown. In this study we have shown that SPA-1 interferes with Rap1 activation by membrane-targeted C3G, C3G-F, in 293T cells through the GTPase activating protein (GAP) activity. SPA-1 transiently expressed in HeLa cells was mostly localized at the cortical cytoskeleton and induced rounding up of the cells, whereas C3G-F conversely induced extensive cell spreading. Conditional SPA-1 overexpression in HeLa cells by tetracycline-regulative system suppressed Rap1 activation upon plating on dishes coated with fibronectin and resulted in the reduced adhesion. When SPA-1 was conditionally induced after the established cell adhesion, the cells gradually rounded up and detached from the dish. Both effects were counteracted by exogenous fibronectin in a dose-dependent manner. Retroviral overexpression of SPA-1 in promyelocytic 32D cells also inhibited both activation of Rap1 and induction of cell adhesion by granulocyte colony stimulating factor without affecting differentiation. These results have indicated that Rap1 GTP is required for the cell adhesion induced by both extracellular matrix and soluble factors, which is negatively regulated by SPA-1.

Animals↗