Biomedical subjects

M Nagai

Publications and source records attributed to M Nagai.

At least 235 records · Page 13Linked to original sources

PubMed1996

Poststatin, a new inhibitor of prolyl endopeptidase. VI. Endopeptidase inhibitory activity of poststatin analogues containing pyrrolidine ring.

Several pyrrolidine-containing analogues of poststatin were synthesized and examined for their inhibitory activity against prolyl endopeptidase and cathepsin B in vitro. Replacement of the postine residue with 2-oxo-2-(2-pyrrolidinyl)acetic acid increased the selectivity and inhibitory activity against prolyl endopeptidase. Benzyloxycarbonyl-L-phenylalanyl-(S)-2-oxo-2- (2-pyrrolidinyl)acetyl-D-phenylalanine was about 46 times as active to propyl endopeptidase as natural poststatin.

Cathepsin B↗

PubMed1996

Poststatin, a new inhibitor of prolyl endopeptidase. VII. N-cycloalkylamide analogues.

Poststatin analogues containing (S)-2-oxo-2-(2-pyrrolidinyl)acetyl moiety in P1 were synthesized and examined for their inhibitory activity against prolyl endopeptidase and cathepsin B in vitro. Introduction of non-peptidyl cycloalkylamine component in P1, was effective and P3-acyl groups must be widely modifiable for prolyl endopeptidase inhibition. Acyl-L-phenylalanyl-(S)-2-oxo-2-(2-pyrrolidinyl)acetyl-cycloalkylamid e type compounds showed IC50 value of nano to subnano g/ml as prolyl endopeptidase inhibitor and were shown no significant inhibitory activities against cathepsin B, a cysteine protease.

Cathepsin B↗

PubMed1996

[A case of Kennedy-Alter-Sung (KAS) syndrome presenting as hypersexuality and elevated serum CK: usefulness of genetic analysis].

We report a unique case of KAS syndrome presenting as hypersexuality and elevated serum creatine kinase (CK). None of the other members of the patient's family had KAS. The patient had engaged in sexual behavior 4 approximately 5 times a week since his marriage. He did not have gynecomastia or hepatomegaly. Neurological examination revealed facial twitching and tongue atrophy and fasciculations. Mild to moderate muscular atrophy and weakness were evident in the proximal portion of the upper and the distal portion of the lower extremities. Deep tendon reflexes were absent, as were sensory disturbance and sphincter dysfunction. Laboratory data showed mild elevation of transaminase (GOT 113 U/L, GPT 69 U/L) and extreme elevation of CK (4,600 U/L) in serum. Electromyography and muscle biopsy from the left biceps showed chronic neurogenic atrophy. Genetic analysis showed increased expansion of a CAG repeat (44 repeats) in exon 1 of the androgen receptor gene. We diagnosed KAS syndrome based on the genetic analysis. This case is important in illustrating the clinical varieties of KAS syndrome, as well as the importance of genetic analysis in KAS syndrome cases presenting with atypical manifestations and without a family history.

Creatine Kinase↗

PubMed1996

Recurrent cold hemagglutinin disease following allogeneic bone marrow transplantation successfully treated with plasmapheresis, corticosteroid and cyclophosphamide.

A 10-year-old male with severe aplastic anemia following allogeneic BMT developed a hemolytic crisis on post-BMT day 67. The diagnosis of cold hemagglutinin disease was made based on the findings of anemia, reticulocytosis, positive direct Coombs test, and markedly elevated cold agglutinins. Anti-nuclear antibody and anti-DNA antibody were also increased. Plasmapheresis was effective as an emergency measure. Corticosteroid after plasmapheresis had a transient effect. At the second episode of hemolysis 6 months after BMT, immunosuppressive therapy with cyclophosphamide plus corticosteroid was successfully administered without negative effect on engraftment.

Anemia, Aplastic↗

PubMed1996

[Successful treatment of acute non-lymphoblastic leukemia from myelodysplastic syndrome by combination of human macrophage colony-stimulating factor (M-CSF) and low dose cytosine arabinoside: M-CSF-induced proliferation and tyrosine phosphorylation in leukemic blasts].

An 84-year-old woman was admitted with acute non-lymphoblastic leukemia transformed from myelodysplastic syndrome. We examined the signal transduction of the leukemic blasts. Stimulation of the blasts by macrophage colony-stimulating factor (M-CSF) resulted in tyrosine phosphorylation of several cellular proteins. In vitro proliferation of leukemic blasts was stimulated by M-CSF, but not by granulocyte colony-stimulating factor. Based upon these findings, combined therapy with M-CSF and low dose cytosine arabinoside (ara-C) was successful. After her recovery, we confirmed marked reduction of blasts and disappearance of M-CSF-responsive cells. These results suggest that M-CSF could enhance the cytotoxic effect of ara-C on leukemic blasts via its intracellular signaling pathway linked to proliferation.

Aged↗

PubMed1996

[Commencement and discontinuance of receiving financial aid for intractable disease treatment].

Data concerning all patients receiving financial aid for 26 types of intractable diseases in 1984, 1988 and 1992 were individually linked. Proportions of patients who discontinued financial aid in 1988 or 1992 among patients who were receiving aid in 1984 (ratio of discontinuance per patients); and ratios of the numbers of patients newly commencing aid in 1988 or 1992 to the numbers of patients who were receiving aid in 1984 (ratio of commencement per patients) were calculated. The results were as follows; 1. Among patients receiving financial aid in 1984, ratios of discontinuance per 100 patients were 28 in 1985-88 and 43 in 1985-92. Ratios of commencement per 100 patients were 96 in 1985-88 and 203 in 1985-92. 2. Ratios of discontinuance and of commencement per 100 patients in 1985-92 among 26 intractable diseases were 27-96 and 31-1,068, respectively. 3. Ratios of discontinuance per patients were higher an age groups 0-19 year and 60 year and over than in other age groups. Ratios of commencement per patients were higher in age groups 20-29 year and 70 year and over than in other age groups. Both ratios were higher among males than among females. 4. Ranges of ratios of discontinuance per patients and of ratios of commencement per patients were smaller among 47 prefectures than among diseases and age groups. The number of patients receiving financial aid in 1984 per population among prefectures was inversely correlated to ratios of commencement per patients, and were not correlated with ratios of discontinuance per patients.

Adolescent↗

PubMed1995

Translocations and amplification of the BCL2 gene are detected in interphase nuclei of non-Hodgkin's lymphoma by in situ hybridization with yeast artificial chromosome clones.

Translocation of the BCL2 gene in B-cell malignancies carrying t(14;18) and amplification of the BCL2 gene in a cell line (HBL-2) derived from a non-Hodgkin's lymphoma (NHL) were detected specifically in both metaphase spreads and interphase nuclei by fluorescence in situ hybridization (FISH) using yeast artificial chromosomes (YACs). A YAC clone containing the BCL2 gene yA153A6, a 360-kb clone spanning from approximately 60 kb upstream of BCL2 exon 1 to approximately 60 kb 3' of the minor breakpoint cluster region, was used for single-color FISH analysis. Seven patients with NHL and one patient with acute lymphoblastic leukemia were analyzed for BCL2 translocations. Interphase nuclei of NHL patients showed three signals when hybridized with the yA153A6 probe. This was expected because the YAC clone spans the BCL2 breakpoint regions on 18q21.3. In a patient with acute lymphoblastic leukemia, a positive signal for BCL2 was detected on der(14) at band 14q32.33 by single-color FISH with the yA153A6 probe, whereas no signals were detected on der(18). The amplification of BCL2 in the HBL-2 cell line was observed on a characteristic abnormal chromosome 18, add(18)(q23); the periodic pattern of the fluorescent signal of this region was suggestive of an amplicon. Using double-color FISH with YAC clones containing the more centromeric 18q21.3 gene gastrin-releasing peptide (y302F10) and the 14q32.33 gene (IgH; Y6), we detected t(14;18) by showing the juxtaposition of the 18q21.3 and 14q32.33 bands on the derivative chromosome 18. Interphase FISH with these YAC clones provided a rapid procedure for the diagnosis of B-cell malignancies carrying t(14;18). In addition, we showed that translocations and amplification of the BCL2 gene can be detected at the single-cell level.

Adult↗

PubMed1995

A novel type of retinoic acid receptor antagonist: synthesis and structure-activity relationships of heterocyclic ring-containing benzoic acid derivatives.

A new series of heterocyclic ring-containing benzoic acids was prepared, and the binding affinity and antagonism of its members against all-trans-retinoic acid were evaluated by in vitro assay systems using human promyelocytic leukemia (HL-60) cells. Structure-activity relationships indicated that both an N-substituted pyrrole or pyrazole (1-position) and a hydrophobic region, with these linked by a ring system, were indispensable for effective antagonism. Among the compounds evaluated, optimal antagonism was exhibited by 4-[4,5,7,8,9,10-hexahydro-7,7,10,-10-tetramethyl-1-(3- pyridylmethyl)anthra[1,2-b]pyrrol-3-yl]benzoic acid (31), 4-[4,5,7,8,9,10-hexahydro-7,7,10,10-tetramethyl-1-(3-pyridylmethyl)-5- thiaanthral[1,2-b]pyrrol-3-yl]benzoic acid (40), and 4-[4,5,7,8,9,10-hexahydro-7,7,10,10-tetramethyl-1-(3- pyridylmethyl)anthra[2,1-d]pyrazol-3-yl]benzoic acid (55), all of which possess a 3-pyridylmethyl group at the five-membered ring nitrogen atom.

Benzoates↗

PubMed1995

Interphase and metaphase detection of the breakpoint of 14q32 translocations in B-cell malignancies by double-color fluorescence in situ hybridization.

The breakpoint of 14q32 translocations found in B-cell malignancies was delineated specifically in both metaphase spreads and interphase nuclei by double-color fluorescence in situ hybridization (FISH) using bacteriophage clones containing the human immunoglobulin gamma chain gene locus (Ig gamma) and a cosmid clone, CY24-68, containing VH segments. CY24-68 is more telomeric than Ig gamma, separated by approximately 1 megabase (Mb). FISH studies were performed on four patients with non-Hodgkin's lymphoma (NHL), one with acute lymphoblastic leukemia (ALL), one with plasma cell leukemia (PCL), and three cell lines. In each patient with t(8;14), t(14;18), and t(3;14), the signal of Ig gamma gene was observed on der(14) and that of CY24-68 at respective partner sites of these translocations, 8q24.1, 18q21.3, and 3q27. Interphase nuclei with a signal of Ig gamma clearly separated from that of CY24-68 were more frequently encountered in all of the patients (45% to 74%) than those in normal controls (4% to 5%). Even in cases where only interphase nuclei were available for FISH studies, 14q32 translocations are detected as shown in two patients each with NHL and t(11;14)-carrying PCL. In two cell lines, HS-1 derived from ALL carrying t(8;14) and FR4 derived from a plasmacytoma carrying a complex form of t(8;14), the signal of Ig gamma was observed at the breakpoint region 8q24.1 of the der(8) in addition to the der(14), indicating that translocation event occurred within the Ig gamma locus. Intense Ig gamma signal was found at the breakpoint region on the der(14)t(11;14) in HBL-2 derived from NHL, indicating amplification of the Ig gamma gene, and presumably the resultant chimeric DNA between Ig gamma and DNA sequences at 11q13. The present approach allowed us to unequivocally detect tumor-specific breakpoints of 14q32 translocations. Furthermore, interphase FISH provides a rapid diagnostic procedure to detect 14q32 translocations in B-cell malignancies.

Burkitt Lymphoma↗

PubMed1995

Studies of the oxidation states of hemoglobin M Boston and hemoglobin M Saskatoon in blood by EPR spectroscopy.

The extent of the oxidation of Hemoglobin (Hb) M Saskatoon (beta 63His-->Tyr) and Hb M Boston (alpha 58His-->Tyr) in the patient's blood was determined by measurement of the intensity of EPR signals at g perpendicular = 6.0 for the normal subunits, g1 = 6.7 for the mutant subunits of Hb M Saskatoon and g1 = 6.3 for those of Hb M Boston, respectively. The amounts of reduced mutant subunits were estimated from the EPR signal intensities and the amounts of Hb present as mutant Hb in the blood. About 50% and 76% of mutant subunits in Hb M Boston and Hb M Saskatoon remained reduced in the fresh blood. Gentle shaking of the blood at 37 degrees C for 15 hours in air brought about autoxidation of the normal subunits as well as the mutant subunits of the two Hbs M, indicating that the presence of the mutant subunits facilitated autoxidation of the normal subunits. Possible involvement of NADH-metHb reductase in erythrocytes in maintenance of the reduced mutant subunits of Hb M Saskatoon was discussed.

Electron Spin Resonance Spectroscopy↗

PubMed1995

Stimulative effects of lead on bone resorption in organ culture.

To clarify whether hypercalcemia after injection of Pb to rats is due to biological bone resorption or physicochemical mineral dissolution, the effect of lead (Pb) on release of previously incorporated 45Ca in organ culture was investigated. Pb at 50 microM and above stimulated the release of 45Ca and hydroxyproline (Hyp). Pb did not stimulate 45Ca release from the bones inactivated by freezing and thawing. Eel calcitonin (ECT), bafilomycin A1 and scopadulcic acid B (SDB) inhibited Pb-stimulated 45Ca release. These results indicate that Pb-induced 45Ca release is due to osteoclastic bone resorption. Pb-stimulated bone resorption was inhibited by indomethacin and flurbiprofen. Pb stimulated the release of prostaglandin E2 (PGE2) from the bones into the media. There was significantly high correlation between 45Ca and PGE2 release. Pb-induced bone resorption was inferred to be mediated by PGE2. From these results, it was suggested that hypercalcemia after Pb injection might be caused by biological bone resorption.

Animals↗

PubMed1995

A macrolide antibiotic, roxithromycin, inhibits the growth of human myeloid leukemia HL60 cells by producing multinucleate cells.

The antiproliferative effect of roxithromycin (RXM) was studied using human myeloid leukemia HL60 cells. RXM inhibited the growth of HL60 cells in a concentration-dependent manner, and significantly inhibited growth at concentrations above 75 microM. This growth inhibition was not associated with specific cell cycle arrest and DNA synthesis was not impaired. In addition, the number of viable cells remained almost unchanged in the presence of 100 microM RXM. RXM induced growth inhibition at least partly by the formation of multinucleate cells. Both flowcytometric and morphological examination revealed that more than 40% of the RXM-treated cells were binucleate. These findings demonstrate that RXM is a potent new modulator of cell cycle progression in HL60 cells and suggest that the inhibition of cytokinesis by this drug may provide a new model for studying mitosis.

Bromodeoxyuridine↗

PubMed1995

Ultraviolet resonance Raman studies of quaternary structure of hemoglobin using a tryptophan beta 37 mutant.

Environmental changes of tyrosine and tryptophan residues of hemoglobin (Hb) upon its T to R transition of quaternary structure were investigated with ultraviolet resonance Raman (UVRR) spectroscopy excited at 235 nm. DeoxyHb A (T-form) showed a UVRR spectrum distinctly different from those of the ligated Hbs (R-form) including oxyHb, COHb, and metHb A, whereas the ligated Hbs exhibited similar UVRR spectra irrespective of the ligand species and the oxidation state of the heme. To characterize the spectral change of Trp-beta 37 at the alpha 1 beta 2 interface due to the quaternary structure transition, the UVRR spectra of Hb A were compared with the corresponding spectra of Hb Hirose (Trp-beta 37-->Ser). A difference spectrum between deoxyHb A and deoxyHb Hirose showed only Trp resonance Raman (RR) bands, which were reasonably ascribed to Trp-beta 37 in deoxyHb A. RR bands at 873 cm-1 (W17) and at 1360 and 1343 cm-1 (W7, Fermi doublet) indicated that the indole ring of Trp-beta 37 in deoxyHb A formed a strong hydrogen bond at the N1H site in hydrophobic environments. Tyr residues in deoxyHb Hirose seemed to be in the same environments as those of deoxyHb A. In contrast, the difference spectrum between Hb A and Hb Hirose in the ligated state displayed peaks for RR bands of both Trp and Tyr. The difference spectra were unaltered by the addition of 5 mM inositol hexaphosphate. This means that the differences were not caused by the tetramer to dimer dissociation but by a conformation change within a tetramer. Comparison of the Hb A-Hb Hirose difference spectra in the oxy and deoxy states revealed that the oxygenation-induced changes of Trp RR bands arose mostly from Trp-beta 37 with the small portion of remaining changes coming from Trp-beta 15, demonstrating that Trp-beta 37 plays a pivotal role in the quaternary structural change in Hb A.

Amino Acid Sequence↗

PubMed1995

Interaction of 6-p-toluidinylnaphthalene-2-sulfonate with beta-cyclodextrin.

The interaction of 6-p-toluidinylnaphthalene-2-sulfonate (TNS) with beta-cyclodextrin was investigated in 0.1 M phosphate buffer at pH 7.4 by fluorescence spectroscopy. Using the fluorescence enhancement of TNS in the presence of beta-cyclodextrin, the thermodynamic parameters for the formation of two kinds of the inclusion complex (molar ratio of beta-cyclodextrin to TNS = 1:1 and 2:1) were determined as follows: delta G degree 1 (1:1 complex) = -20.0 kJ mol-1 at 25 degrees C, delta H degree 1 = -19.6 kJ mol-1, delta S degree 1 = -1.7 J mol-1 K-1, delta G degree 2 (2:1 complex) at 25 degrees C = -6.14 kJ mol-1, delta H degree 2 = -2.80 kJ mol-1, delta S degree 2 = 16.7 J mol-1 K-1. From the thermodynamic parameters, the main driving force for the 1:1 inclusion complex formation was considered to be the van der Waals-London dispersion force, while the contribution of the hydrophobic interaction was small. Also, the hydrogen bonding was suggested to contribute to the inclusion complex formation. The main driving force for the 2:1 inclusion complex formation was the hydrophobic interaction. Also, from the measurements of proton nuclear magnetic resonance spectra and studies with Corey-Pauling-Koltun atomic models, the probable structure was determined and discussed in connection with the thermodynamic parameters.

Cyclodextrins↗

PubMed1995

Differential effect of TGF-beta 1 on the in vitro activation of HTLV-I and the proliferative response of CD8+ T lymphocytes in patients with HTLV-I-associated myelopathy (HAM/TSP).

While considerable information is available on the pathogenesis of human T lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP), fundamental questions remain unanswered. In particular the clinicopathological uniformity of the disorder among patients remains poorly understood. The potential role of TGF-beta as a preferential immune regulator in the CNS and the functional heterogeneity of TGF-beta has led us to assess the possible involvement of this cytokine in the pathogenic process. To investigate this, the modulatory effects of TGF-beta 1 on HTLV-I-induced in vitro phenomena were evaluated using fractionated lymphocytes from patients with HAM/TSP. It could be shown that the proliferative response of CD8+ cells against cultured and irradiated autologous CD4+ cells possessing HTLV-I antigens was significantly inhibited by TGF-beta 1. However, the in vitro activation of HTLV-I, which was evaluated by spontaneous proliferation of CD4+ cells, was unaffected by TGF-beta 1. The induction of intracytoplasmic HTLV-I antigens in cultured CD4+ cells was facilitated by TGF-beta 1 in a dose-dependent manner. These findings suggest that TGF-beta may have a critical role in localized viral activation within the CNS in patients with HAM/TSP.

Adult↗

PubMed1995

A follow-up study of patients with cervical cancer after resection, with special emphasis on the incidence of second primary cancers.

The causes of death in long-term survivors after resection of cervical cancer were investigated in a follow-up study of 375 women, focusing especially on the postoperative development of second primary cancers. The 5- and 10-year overall survival rates were 75.0 and 66.0%, respectively, in cases that showed frank invasion, 94.7 and 92.8%, respectively, in those showing microinvasion, and 96.2 and 96.2% respectively, in those showing carcinoma in situ. Multivariate analysis identified patient age and cancer stage at the time of diagnosis as separate factors prognostic for overall survival. During the observation period, 10 patients developed a second primary cancer, but no significantly elevated risk of developing a second primary cancer was demonstrated. However, during the same period, 20 patients also died of noncancerous disease, 9 of this number succumbing to acute myocardial infarction and/or heart failure. These results suggest that patients with cervical cancer may not have an increased risk of developing second primary cancer. It is felt that continued follow-up of long-term cervical cancer survivors should be pursued in order to prevent or arrest the development of noncancerous disease and/or second primary cancer, so that increased prolongation of survival can be achieved.

Adult↗

PubMed1995

Evolution of Mirizzi syndrome with biliobiliary fistula.

The mechanisms of fistula formation were analyzed in eight patients with Mirizzi syndrome with biliobiliary fistula. The fistula was type 1 in three patients and type 2 in five, according to the Corlette-Bismuth classification. The apparent mechanisms of fistula formation include inflammation of the gallbladder, its subsequent fusion to the bile duct, and increase in the internal pressure due to either contraction of the gallbladder or multiple stones. However, no predisposing conditions other than a longstanding history of cholelithiasis have been suggested. Differences in the type of fistula are considered to be due to the mode of fusion of the gallbladder to the bile duct, and the size of the perforation, which is apparently determined by the area in contact with the stone.

Adult↗

PubMed1995

Effects of heparin, sperm concentration and bull variation on in vitro fertilization of bovine oocytes in a protein-free medium.

The present study was conducted to examine the effects of heparin, sperm concentration and bull variation on the fertilization of bovine oocytes in a protein-free medium supplemented with polyvinyl alcohol and subsequent in vitro development of fertilized embryos. The effects in protein-free medium were compared with those in medium supplemented with bovine serum albumin (BSA). In the presence of heparin (1, 10 and 100 microg/ml), nearly all the oocytes were fertilized with and without BSA. In the absence of BSA, polyspermy was lower (4 to 15%) than in its presence (15 to 48%; P < 0.05). An increase in sperm concentration from 1 x 10(4) cells/ml during insemination enhanced fertilization rate up to 1 x 10(6) cells/ml with and without BSA (14 to 90% and 3 to 77%, respectively). In the absence of BSA, the highest concentration of spermatozoa (1 x 10(7) cells/ml) gave a lower fertilization rate (55%) than that at 1 x 10(6) cells/ml (77%; P < 0.05). Polyspermy neither increased nor decreased sperm concentration without BSA (0 to 8%; P > 0.05). The effects of spermatozoa from 5 different bulls chosen randomly on in vitro fertilization in medium without BSA were examined. Individual bull variation in fertilization rate (36 to 95%) was noted at 3 different heparin concentrations (1, 10 and 100 microg/ml). Polyspermic fertilization was low (0 to 14%) and was the same for all bulls at all heparin concentrations. Embryos fertilized without BSA developed to the blastocyst stage at the same rate (27%) as those with BSA (33%; P > 0.05).

Journal Article↗