The efficacy of oral beraprost sodium, a prostaglandin I2 analogue, for treating intermittent claudication in patients with arteriosclerosis obliterans.

AIM: This study aimed to evaluate the effect of oral beraprost sodium, a prostaglandin I2 analogue, on symptoms of intermittent claudication in patients with arteriosclerosis obliterans. The research design consisted of a before and after treatment study without comparison groups. The subjects comprised arteriosclerosis obliterans patients who experienced intermittent claudication. Furthermore, this study aimed to assess the mechanism of action of beraprost sodium via blood sampling and measurements of flow-mediated vasodilatation before and after treatment. METHODS: The study was performed prospectively in 7 patients with arteriosclerosis obliterans. Beraprost sodium (40 microg) was orally administered to 7 patients at study entry, followed by administration of 120 microg/day for 12 weeks. Blood sampling and measurements of flow-mediated vasodilatation were performed before and after treatment at study entry, 4 weeks, and 12 weeks after treatment. Treadmill exercise tests were performed three times at study entry, 4 weeks, and 12 weeks after treatment. The ankle-brachial index (ABI) was measured at rest and after exercise. RESULTS: Pain-free walking distances increased by 138% at 12 weeks after treatment. Maximum walking distances increased by 133%. The ABI was significantly increased at 4 weeks and 12 weeks after treatment at rest. Endothelin-1 levels tended to be decreased at 1 h after administration of 40 microg beraprost sodium. N(G),N(G)-dimethyl-L-arginine, nitrate ions, and flow-mediated vasodilatation. CONCLUSION: Beraprost sodium tended to decrease endothelin-1 levels and improved symptoms of intermittent claudication in patients with arteriosclerosis obliterans.

Biologically active oligodeoxyribonucleotides. Part 12: N2-methylation of 2'-deoxyguanosines enhances stability of parallel G-quadruplex and anti-HIV-1 activity.

2'-Deoxyguanosine residues of a 3',5'-end-modified hexadeoxyribonucleotide (R-95288) with anti-HIV-1 activity were substituted with N2-methyl-2'-deoxyguanosine (m2dG). These modified oligodeoxyribonucleotides (ODNs) showed a 2-fold higher activity than R-95288. Also, the CD spectra of these ODNs indicated that the m2dG modification stabilized the tertiary structure of the G-quadruplex.

Synthesis and anti-HIV activity of arylpiperazinyl fluoroquinolones: a new class of anti-HIV agents.

Synthesis and anti-HIV activity of a series of novel arylpiperazinyl fluoroquinolones are reported. In the SAR study, the aryl substituents on the piperazine nitrogen were found to play an important role for the anti-HIV-1 activity. A few of the compounds exhibited potent anti-HIV activity: IC50=0.06 microM in chronically infected cells.

A new fluoroquinolone derivative exhibits inhibitory activity against human immunodeficiency virus type 1 replication.

The inhibitory activity of several fluoroquinolone antibiotics against human immunodeficiency virus type 1 (HIV-1) replication was investigated. R-71762, (+/-) 9-fluoro-3-fluoromethyl-2, 3-dihydro-10-[4-(2-pyridyl)-1-piperazinyl]-7-oxo-7H-pyrido[1,2, 3-de][1,4]benzoxazine-6-carboxylic acid, protected MT-4 cells from HIV-1-induced cytopathic effects. Furthermore, the compound inhibited virus replication both in acutely and in chronically HIV-1-infected cells. On the other hand, ofloxacin, levofloxacin, ciprofloxacin, norfloxacin and enoxacin, that were previously reported to be protective against HIV-1-induced cytopathic effects, did not show any protective activity in our assay system. These results indicate that R-71762 is a novel inhibitor of HIV-1 replication and is effective even in HIV-1 chronically infected cells.

Biologically active oligodeoxyribonucleotides. 5. 5'-End-substituted d(TGGGAG) possesses anti-human immunodeficiency virus type 1 activity by forming a G-quadruplex structure.

A series of hexadeoxyribonucleotides (6-mers), d(TGGGAG), substituted with a variety of aromatic groups at the 5'-end were synthesized and tested for anti-human immunodeficiency virus type 1 (HIV-1) activity. While unmodified d(TGGGAG) (31) had no anti-HIV-1 activity, compound 23 with a 3,4-di(benzyloxy)benzyl (DBB) group at the 5'-end potently inhibited the HIV-1IIIB-induced cytopathicity of MT-4 cells in vitro (IC50 = 0.37 microM) without cytotoxicity up to 40 microM. A thermal denaturation study on the 5'-end-substituted 6-mers by means of the circular dichroism (CD) spectra demonstrated that the aromatic substituent attached at the 5'-end of the 6-mer strongly enhanced the formation of a parallel helical structure consisting of four strands (quadruplex). On the contrary, compound 36, in which one of the guanosines of 23 was replaced by a thymidine, did not form a quadruplex, thus exhibiting no anti-HIV-1 activity. Moreover, both compound 15, with a tert-butyldiphenylsilyl group solely at its 3'-end, and compound 21, with a relatively small substituent, a benzyl group, at the 5'-end, formed quadruplexes but had no anti-HIV-1 activity. These findings led us to the conclusion that both the quadruplex structure and the aromatic substituent with adequate size at the 5'-end are crucial for the interaction of the 5'-end-substituted 6-mers with the V3 loop as well as the CD4 binding site on viral gp120, resulting in anti-HIV-1 activity.

Biologically active oligodeoxyribonucleotides. 10: anti-HIV-1 activity and stability of modified hexanucleotides containing glycerol-skeleton.

Deoxyribose-moieties of modified hexadeoxyribonucleotide 1, which exhibits anti-HIV-1 activity, were partially replaced with glycerol-moieties. Compound 7 with two glycerylguanines at its 3'-end showed more potent anti-HIV-1 activity and more stability against digestion by nucleases than the parent compound 1.

Biologically active oligodeoxyribonucleotides. Part 11: The least phosphate-modification of quadruplex-forming hexadeoxyribonucleotide TGGGAG, bearing 3-and 5-end-modification, with anti-HIV-1 activity.

We have found that a hexadeoxyribonucleotide (5'TGGGAG3', R-95288), Koizumi, M. et al. Bioorganic & Medicinal Chemistry, 1997, 5, 2235, bearing a 3,4-dibenzyloxybenzyl (3,4-DBB) group at the 5'-end and a 2-hydroxyethylphosphate at the 3'-end, has high anti-HIV-1 activity and the least cytotoxicity in vitro and in vivo. In order to synthesize more potent hexadeoxyribonucleotides, we substituted phosphodiester (P-O) bonds in the 6-mer with the least phosphorothioate (P-S), phosphoramidate (P-N), or methylphosphonate (P-Me) bonds. When more than two P-N or P-Me bonds were introduced into a 6-mer, the phosphate-modified 6-mers had weak or no anti-HIV- activity, in spite of quadruplex structure formation. However, when P-S bonds were substituted for P-O bonds, anti-HIV-1 activity of their 6-mers did not dramatically decrease, compared with compounds substituted with P-N or P-Me bonds. The results suggest that the formation of a quadruplex structure is not always sufficient for anti-HIV-1 activity of the 6-mer, and that net negative charges derived from P-O or P-S bonds in the quadruplex are important for anti-HIV-1 activity. Moreover, among various phosphate-modified ODNs, we found that the anti-HIV-1 activity of ODN PS7 with only one P-S bond was the same as that of R-95288, both having a high stability in human plasma.

Biologically active oligodeoxyribonucleotides--IX. Synthesis and anti-HIV-1 activity of hexadeoxyribonucleotides, TGGGAG, bearing 3'- and 5'-end-modification.

We have determined that hexadeoxyribonucleotides (5'TGGGAG3'), with modified aromatic groups such as a trityl group at the 5'-end, have anti-HIV-1 activity in vitro. The 6-mer bearing a 3,4-dibenzyloxybenzyl (3,4-DBB) group at the 5'-end had the most potent activity and the least cytotoxicity. When the 3'-end of the 5'-(3,4-DBB)-modified 6-mer was substituted with a 2-hydroxyethylphosphate, a 2-hydroxyethylthiophosphate, or a methylphosphate group at the 3'-end, anti-HIV-1 activity increased. Moreover, among various 3'- and 5'-end-modified 6-mers that were tested, the 6-mer (R-95288) bearing a 3,4-DBB group at the 5'-end and a 2-hydroxyethylphosphate group at the 3'-end was the most stable, when incubated with mouse, rat, or human plasma. Therefore, R-95288 was chosen as the best candidate for possible use in therapy on the basis of its anti-HIV-1 activity.

[Evaluation of gelatin particle agglutination method for detection of Treponema pallidum antibody].

Treponema pallidum hemagglutination (HA) is one of the most frequently used methods for the detection of Treponema pallidum (T. pallidum) antibodies. Recently, an innovative agglutination method using artificial carriers was newly developed, and is now available as a routine method. In order to compare the newly developed particle agglutination (PA) method (FUJIREBIO INC.) with the conventional HA method, T. pallidum antibody titers of numerous sera were measured by respective methods. In the stability study, reconstituted reagent was stable for at least three weeks. Sample inactivation (56 degrees C/30 min) demonstrated no effect on the test results. Among 800 sera, 132 (16.6%) positives (+), 633 (79.1%) negatives (-) and (4.3%) indeterminates (+) were obtained by HA method. Meanwhile, 144 (18.0%) positives (+), 627 (78.4%) negatives (-) and 29 (3.6%) indeterminates (+) were obtained by PA method. The correlation between PA and HA method was 97.8%, and the antibody titers obtained by PA method showed good correlation with HA method. Those samples which showed discrepancy between PA and HA method in the above study were further examined with fluorescent treponemal antibody-absorption (FTA-ABS) method. The results obtained from FTA-ABS method were almost consistent with those obtained from PA method. For respective syphilis patients in stage I and II, antibody titer was monitored by HA, PA and RPR method. The results indicated that changes in antibody titer obtained from PA method was approximately the same as the titer changes obtained from RPR method. Namely, PA method detected the presence of IgM earlier than HA method.(ABSTRACT TRUNCATED AT 250 WORDS)

Genomic organization of the human homologue of the rat pancreatic elastase I gene.

The homologue of the rat pancreatic elastase I gene was found in the human genome, but its transcription was completely suppressed in the adult human pancreas as we reported previously. In this study, we characterized the complete structure of the eight putative exons of the silent gene for human elastase I. A genotype analysis of the exon 1 DNA sequence revealed that at least two allelic elastase I genes are present in human genomes. A primate-specific repetitive DNA element (MER1) was identified in the 3'-flanking region of the human elastase I gene. The primary structure of human preproelastase I, deduced from the sequences of the eight exons, showed an 89% identity with that of porcine or rat pancreatic preproelastase I. The amino acid residues of the serine protease catalytic triad and the eight cysteine residues conserved in the elastase family were present at positions equivalent to those observed in porcine and rat elastase I, suggesting that the gene product may function as an elastolytic enzyme if this gene is expressed in any tissue.

Characterization of a silent gene for human pancreatic elastase I: structure of the 5'-flanking region.

A cDNA for porcine pancreatic elastase I has been cloned and used as a probe for blot hybridization analysis. Southern blot analysis of total DNA demonstrated that the elastase I gene is conserved among the porcine, rat, calf, and human genomes. Northern blot analysis, however, indicated that the elastase I gene is not expressed in the human adult pancreas, even though abundant expression is observed in the rat and porcine pancreas. Sequence analysis of the cloned human elastase I gene revealed that the proximal 5'-flanking region from -1 to -200 shows 78% identity with that of the actively transcribed rat elastase I gene, and contains a consensus TATA box and a putative tissue specific enhancer sequence. The transcriptional activity of the human elastase I gene appears to be suppressed in the human adult pancreas.