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S Harada

Publications and source records attributed to S Harada.

At least 541 records · Page 30Linked to original sources
PubMed1986

Prostaglandin E2, a seminal constituent, facilitates the replication of acquired immune deficiency syndrome virus in vitro.

Acquired immune deficiency syndrome (AIDS)-associated virus is thought to be transmitted effectively through semen during sexual activities from male to male or from male to female. Prostaglandin (PG) E2 is one of the immunosuppressive compounds present in high concentrations in human semen. We, therefore, investigated direct effects of PGE2 and other PGs on AIDS-associated virus infection and replication in vitro. First, type III human T-lymphotropic virus (HTLV-III) was used to infect a T-cell line (MT-4) in culture. PGE2 (10 nM to 10 microM) added to the culture medium enhanced the production of infectious virus in a dose-dependent fashion. In the presence of 5 microM PGE2, 2.5-fold more virus were released from the infected MT-4 cells as compared to untreated control cells on day 3 after infection. Second, when we used an HTLV-III continuous-producer cell line (Molt-4/HTLV-III), PGE2 and PGD2 added to the culture medium increased the number of viruses released from Molt-4/HTLV-III cells. Other PGs such as PGF2 alpha and 13,14-dihydro-15-keto PGE2 did not affect the replication of HTLV-III in this system. These results indicate that some PGs including seminal PGs enhance the AIDS-associated virus replication in vitro. We propose that PGE2 in human semen might directly facilitate the infection of AIDS-associated virus and cause the efficient transmission of the virus during sexual activities.

Cell Transformation, Viral↗
PubMed1986

Crystal structures of modified myoglobins. I. Heme orientation and structural changes around heme in myoglobins reconstituted with isopemptoheme, pemptoheme, 2-ethyldeuteroheme, and 4-ethyldeuteroheme.

The crystal structures of sperm whale metmyoglobins reconstituted with four modified hemes, isopemptoheme, pemptoheme, 2-ethyldeuteroheme, and 4-ethyldeuteroheme, have been determined and refined at 2.2 A resolution to R = 0.217, 0.218, 0.213, and 0.222, respectively. All the crystals of these myoglobins are isomorphous with that of native metmyoglobin. The structural changes of the modified myoglobin from the native myoglobin were examined on difference Fourier maps; the orientation of 4-ethyldeuteroheme in the heme pocket is such that the heme is rotated by 180 degrees about an axis through the alpha-gamma-meso carbons, whereas the orientations of the other three hemes are the same as that of the protoheme in the native myoglobin. The changes of the structures around the heme become greater in the order of isopemptoheme, 2-ethyldeuteroheme less than pemptoheme less than 4-ethyldeuteroheme. The magnitudes of the changes seem to be related to the oxygen affinities of these four reconstituted myoglobins.

Animals↗
PubMed1986

Crystal structures of modified myoglobins. II. Relation between oxygen affinity properties and structural changes around heme in myoglobins reconstituted with 2,4-diisopropyldeuteroheme, 2-isopropyl-4-vinyldeuteroheme, and 2-vinyl-4-isopropyldeuteroheme.

The crystal structures of sperm whale metmyoglobins reconstituted with three kinds of modified hemes, 2,4-diisopropyldeuteroheme, 2-isopropyl-4-vinyldeuteroheme, and 2-vinyl-4-isopropyldeuteroheme, have been determined and refined at 2.2 A resolution to R = 0.216, 0.219, and 0.195, respectively. All the crystals of these myoglobins are isomorphous with that of native metmyoglobin. The 2-vinyl-4-isopropyldeuteroheme was found to be in a reverse orientation, in which the heme plane is rotated by 180 degrees about an axis through the alpha-gamma-meso carbons, whereas the orientations of the other two hemes were the same as that of protoheme in native myoglobin. In the myoglobins with 2,4-diisopropyldeuteroheme and 2-vinyl-4-isopropyldeuteroheme, both of which have lower oxygen affinities than native myoglobin, the bulky isopropyl side chain pushes Phe 43 0.7 A toward His 64 (the distal histidine) in the former, and the whole E helix at most 1.5 A, including a 0.7 A shift of the His 64 imidazole ring, in the latter. The changes of the structures prevent His 64 from forming a hydrogen bond with the liganded oxygen molecule, so that these two modified myoglobins show low oxygen affinities. On the other hand, there is no such drastic displacement in myoglobin with 2-isopropyl-4-vinyldeuteroheme, which has a slightly higher oxygen affinity than native myoglobin.

Animals↗
PubMed1986

HLA-DR2 and Dw2 in narcolepsy and in other disorders of excessive somnolence without cataplexy.

Studies on HLA antigens were conducted in several patient populations with the following findings: (a) All 135 Japanese narcoleptic patients, eight of whom were considered to have "symptomatic" narcolepsy, were found to be HLA-DR2 and HLA-DQw1 positive. All 17 members of a subgroup of the original population were also found to be HLA-Dw2-positive. It was concluded that HLA-DR2 is a prerequisite for the development of narcolepsy and that the diagnosis of narcolepsy can be excluded if HLA-DR2 or HLA-Dw2 is negative. The distinction between idiopathic and symptomatic narcolepsy needs to be reconsidered. (b) Haplotype studies in three families with narcoleptic members enabled detection of children at high risk for narcolepsy. (c) Of the 54 patients with disorders of excessive daytime sleepiness other than narcolepsy, those with essential hypersomnia (EHS) had a higher frequency of HLA-DR2; the others had a lower frequency. The DR2-positive EHS group could include members with an incomplete form of narcolepsy; the DR2-negative EHS group had disorders essentially different from narcolepsy, although both positive and negative groups manifested hypnagogic hallucinations, sleep paralysis, and sleep onset REMs. Two further studies were conducted in subgroups of the original narcoleptic population studied. In a subgroup of 30 patients who underwent lymphocyte subset studies, no T-cell abnormalities were detected; it is unlikely that an autoimmune mechanism is involved in the development of narcolepsy. In a subgroup of 33 narcoleptic patients, Southern's blot analysis of DNA using a DQ beta probe revealed three specific restriction fragments. Further studies are necessary to locate the DNA locus that carries the susceptibility gene for narcolepsy.

Alleles↗
PubMed1986

Quantitative evaluations of the effect of UV irradiation on the infectivity of HTLV-III (AIDS virus) with HTLV-I-carrying cell line, MT-4.

The effect of UV irradiation on HTLV-III was quantitatively studied to evaluate the dosage of UV irradiation which inactivates the virus for sterilization of blood products and for laboratory decontamination. In order to estimate the biologic activity and quantitation of the virus, induction of HTLV-III-specific antigens and inhibition of DNA synthesis in MT-4 cells infected by UV-irradiated HTLV-III were detected by indirect immunofluorescence technique and proliferation assay using [3H]thymidine uptake, respectively. Furthermore, plaque-forming assay was performed to count the infectious viral particles. Results showed that HTLV-III was completely inactivated by 5000 J/m2 UV irradiation. Cloned UV-irradiated HTLV-III (UV-1) was obtained from a plaque that was formed by 2000 J/m2 UV-irradiated virus. When MT-4 cells were infected by the clone UV-1, ballooning degeneration of cells was predominantly induced. These ballooning cells were not usually observed in MT-4 cells infected by unirradiated HTLV-III. The resistance to UV was not different between clone UV-1 and unirradiated HTLV-III.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Serological differences between human T-lymphotropic virus type-I (HTLV-I) and HTLV-III/LAV.

Sera from each of five preselected groups of patients with acquired immune deficiency syndrome (AIDS), AIDS-related complex (ARC), hemophilia, adult T-cell leukemia (ATL), and healthy controls were examined for antibodies to human T-cell leukemia (T-lymphotropic) virus type-I (HTLV-I) and HTLV-III by indirect immunofluorescence (IF) and radioimmunoprecipitation (RIP) methods. All sera from five patients with AIDS, ARC, and hemophilia reacted at titers from 1 : 512 to 1 : 5,120 with fixed H9/HTLV-III cells by IF but not with fixed MT-1 cells carrying HTLV-I. Similarly, sera from patients with AIDS, ARC, and hemophilia precipitated HTLV-III-specific polypeptides of 120K, 46K, and 24K. In contrast, sera from five patients with ATL did not react with fixed H9/HTLV-III cells, but reacted with fixed MT-1 cells. Moreover, HTLV-I-specific polypeptides of 68K, 28K, and 24K were precipitated with sera from ATL-patients but not with anti-HTLV-III-positive sera. Recently, we infected HTLV-I-carrying MT-4 cells with HTLV-III and provoked strong cytopathic effects. This system enabled testing for neutralizing antibodies to HTLV-III. Neutralizing titers to HTLV-III of five anti-HTLV-III-positive sera ranged from 1 : 720 to 1 : 9,000. In contrast, all five seronegative controls showed no or only low reactivity to HTLV-III envelope (1 : 80 and 100). However, three out of five anti-HTLV-I-positive sera exhibited weak cross-reactivities with HTLV-III. The reactivities were expressed as less than 1 : 160, except for one case (1 : 720). They were considered to be nonspecific since they were negative for HTLV-III antibodies in the radioimmunoprecipitation studies.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Inhibition of replication and cytopathic effect of human T cell lymphotropic virus type III/lymphadenopathy-associated virus by 3'-azido-3'-deoxythymidine in vitro.

Human T cell lymphotropic virus type III (HTLV-III)/lymphadenopathy-associated virus is the etiologic agent of the acquired immune deficiency syndrome (AIDS) and AIDS-related complex. The effect of 3'-azido-3'-deoxythymidine (AZT) on the HTLV-III/lymphadenopathy-associated virus infection was quantitatively studied with HTLV type I-carrying MT-4 cells. The AZT compound inhibited HTLV-III-induced cytopathic effect and virus-specific antigen expression in MT-4 cells at concentrations of 5 and 10 microM. In addition, a plaque-forming assay was performed to assess the effect of AZT on virus replication in MT-4 cells freshly infected with HTLV-III and in continuous HTLV-III-producing Molt-4/HTLV-III cells. Results showed that AZT efficiently and effectively inhibited the replication of HTLV-III in infected MT-4 cells. AZT is a strong inhibitor of reverse transcriptase activity of HTLV-III as a triphosphate, to such a degree that even 1.0 pM azido-TTP inhibits 50% of reverse transcriptase activity. However, it did not show any effect in the HTLV-III-producing cell line Molt-4/HTLV-III. Thus, AZT has no effect on virus replication of an already integrated virus. When 5 microM AZT was added to HTLV-III-infected MT-4 within 20 h after infection, a striking suppressive effect was noticed. This concentration was much lower than that which inhibits the growth of MT-4 cells. These results confirm those found in a previous report (H. Mitsuya, K. J. Weinhold, P. S. Furman, H. S. Clair, S. N. Lehrman, R. C. Gallo, D. Bolognesi, D. W. Barry, and S. Broder, Proc. Natl. Acad. Sci. USA 82:7096-7100, 1985) and suggest that AZT might be used as an experimental antiviral agent for AIDS and AIDS-related complex.

Antigens, Viral↗
PubMed1986

Essential structure in the cloned transforming DNA that induces gene amplification of the Bacillus subtilis amyE-tmrB region.

Bacillus subtilis B7, a mutant which acquired gene amplification of the amyE-tmrB region, showed, as a result, hyperproductivity (about a 5- to 10-fold increase) of alpha-amylase and tunicamycin resistance. The mutational character was transferred to recipient cells by competence transformation. A 14-kilobase (kb) EcoRI chromosomal DNA fragment of strain B7 was found to have the transforming activity. We cloned a 6.4-kb EcoRI fragment on a phage vector lambda Charon 4A through a spontaneous deletion of 7.6 kb from the 14-kb fragment and subcloned a 1.6-kb HindIII fragment on pGR71. The cloned 6.4-kb EcoRI and 1.6-kb HindIII fragments retained the transforming activity of inducing gene amplification of the amyE-tmrB region. At the junction point (J) of the repeating units (16 kb), the tmrB gene was linked to a DNA region (M) located 4 kb upstream of amyE. The essential structure of the cloned, transforming (gene amplification-inducing) DNA was deduced to be that around J. The subcloned 1.6-kb HindIII fragment that retained the transforming activity was shown to be almost solely composed of the tmrB-J-M region. In addition, the DNA sequence around J was determined.

Bacillus subtilis↗
PubMed1986

Differential susceptibility to the acquired immunodeficiency syndrome retrovirus in cloned cells of human leukemic T-cell line Molt-4.

Cells of human leukemic T-cell line Molt-4 which were cloned in soft agarose from individual colonies were analyzed for the cytopathic effect and viral antigen expression after human T-cell lymphotropic virus type III infection. The induction of cytopathic effect and viral antigens by the infection varied significantly among the different cell clones. These clones did not show significant differences in the amount of OKT-4 antigen, a possible surface receptor for acquired immunodeficiency syndrome virus. Moreover, the virus-producing ability and the susceptibility to the virus of each clone appeared to be separable.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Detection and isolation of an acquired immune deficiency syndrome (AIDS)-related virus (HTLV-III/LAV) from a Japanese boy with AIDS-related complex.

We attempted to isolate acquired immune deficiency syndrome (AIDS) virus from a Japanese hemophiliac with AIDS-related complex (ARC). After cocultivation of leukocytes from his peripheral blood with those of a healthy adult, reverse transcriptase activity and AIDS viral antigens were detected by immunofluorescence and radio-immunoprecipitation methods, respectively. Moreover, an electron microscopic study revealed the presence of viral particles consistent with AIDS virus. These retroviruses were further propagated. We designated the first Japanese isolate of AIDS virus as YU-1.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Narrow host range of AIDS-related retroviruses (YU-1, 2, 3, 4) isolated from Japanese hemophiliacs: inability to infect H9, Molt-4, and MT-4 cells.

Infectivity was assayed by infecting human T-lymphocytes, H9, Molt-4, and MT-4 cells with different strains of AIDS viruses (HTLV-III, LAV, ARV, and YU viruses). Human T-lymphotropic virus type-III (HTLV-III), lymphadenopathy-associated virus (LAV), and AIDS-associated retrovirus (ARV) were able to infect all kinds of target cells tested and to induce virus-specific antigens, whereas Japanese isolates, YU viruses, infected only interleukin-2-dependent human T-lymphocytes. Long-term propagation of the YU viruses and pretreatment of the cells with Polybrene did not allow the YU virus to produce viral antigens by infecting H9, Molt-4, and MT-4 cells. Thus, YU viruses have a rather narrow host range as compared with HTLV-III, LAV, and ARV. These different infectivities may be reflected in the progress and symptoms of AIDS in vivo.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Substances affecting the infection and replication of human immunodeficiency virus (HIV).

The effects of various compounds were studied quantitatively on the growth of human immunodeficiency virus (HIV). For this we used a human T-cell leukemia virus type I carrying cell line, MT-4 which is most permissive for HIV infection. The results are summarized as follows: 1) Prostaglandin E2 and 12-0-tetradecanoylphorbol-13-acetate enhanced the production of HIV significantly in MT-4 cells as well as a continuous HIV producer Molt-4/HTLV-III cells. 2) Interferon gamma, retinoic acid and 3'-azido-3'-deoxythymidine inhibited the replication of HIV at the concentrations which were not cytotoxic. Mechanism of action of these compounds and its clinical implications are discussed.

Cell Line↗
PubMed1986

A novel agglutination test for the human immunodeficiency virus antibody: a comparative study with enzyme-linked immunosorbent assay and immunofluorescence.

A new serological test, the gelatin particle agglutination (PA) test, was developed for the detection of antibody to human immunodeficiency virus (HIV). The sensitivity of the PA test was the same as that of enzyme-linked immunosorbent assay (ELISA) among 761 US and Japanese sera tested. However, false-positive cases were found in 1.2% of all sera in ELISA but in 0% in the PA test (P less than 0.05). There was 100% agreement of seropositivity between PA and a confirmatory indirect immunofluorescence (IF) test. In addition, the agglutination test was reproducible. Thus, the test should be useful for the mass screening of anti-HIV antibody in blood donors.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Reproductive toxicity of ofloxacin.

The reproductive toxicity of (+/-)-9-fluoro-2, 3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-7H-pyrido[1,2,3-de] [1,4]benzoxazine-6-carboxylic acid (ofloxacin, Tarivid), a new antibacterial agent, was investigated in rats and rabbits after oral administration. Neither the male or female fertility nor the reproductive performance of the rats was affected by doses of up to 360 mg/kg. Ofloxacin elicited no evidence of teratogenicity when administered orally during the period of organogenesis to pregnant rats at doses of up to 810 mg/kg, or to pregnant rabbits at doses of up to 160 mg/kg. However, the female rats receiving 810 mg/kg showed salivation, dirty hair coats, soft stools, and decreases of body weight and food intake. The fetuses in the higher dose groups exhibited decreased body weight and retardation of ossification, and those in the highest dose group showed increased mortality and skeletal variations (cervical ribs, shortened 13th ribs). Further investigation of the fetal skeleton revealed that the critical period of the occurrence of skeletal variations was on days 9 and 10 of gestation. The occurrence of cervical ribs and shortened 13th ribs was not an indicator of teratogenicity when ofloxacin was administered at doses of up to 1600 mg/kg during the critical period. Moreover, the shortening of the 13th ribs was the only type of retardation of ossification degree. Decreases of maternal body weight and food intake, and increased mortality of fetuses were observed in rabbits at a dose of 160 mg/kg. In a perinatal and postnatal toxicity study in rats using doses of up to 360 mg/kg, no adverse effects were observed.

Animals↗
PubMed1986

The dissociation between the plasma levels of aminopeptidases A and B in spontaneously hypertensive rats.

We performed a longitudinal study for 20 weeks on spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKR) to determine the relationship between peptide metabolism and the age-dependent increase in blood pressure. In both SHR and WKR, the plasma level of aminopeptidase A (AP-A) clearly showed an age-dependent decrease. The plasma level of aminopeptidase B paralleled that of AP-A in WKR, but such an age-dependency was not observed in SHR, thus showing a dissociation between the two aminopeptidases. With age in both strains, the level of angiotensin-converting enzyme tended to decrease, while that of kallikrein activity tended to increase. In addition to these findings, a multivariate study testing the relationship of blood pressure to these enzyme activities, as well as to plasma levels of angiotensin I and renin activity, suggested abnormalities in the networks of proteolytic enzymes and in the peptide metabolism surrounding the renin-angiotensin system in SHR. These abnormalities may play some important roles in pathophysiological mechanisms of hypertension in SHR.

Aging↗
PubMed1986

Biosynthesis of an unusual amino acyl moiety contained in bestatin.

The biosynthetic pathway of an unusual amino acyl [(2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl (AHP)] moiety which is contained in bestatin has been studied by testing the incorporation of potential precursors. L-[U-14C]-Phenylalanine, L-[U-14C]leucine, and [U-14C]acetic acid were efficiently incorporated into bestatin, but the radioactivity of L-[1-14C]phenylalanine, [1-14C]glyoxylic acid, and [14C]oxalic acid were not incorporated. Incorporation of acetic acid into 1- and 2-carbon of the AHP moiety was confirmed by incorporation of [13C]acetic acid. Thus, the AHP moiety was shown to be biosynthesized from L-phenylalanine and two carbon atoms of acetic acid, accompanied by decarboxylation of the phenylalanine.

Acetates↗