Search PubMed⌕ Search

Biomedical subjects

A Fukushima

Publications and source records attributed to A Fukushima.

At least 55 records · Page 3Linked to original sources

Characterization of functional domains of an embryonic stem cell coactivator UTF1 which are conserved and essential for potentiation of ATF-2 activity.

We have recently cloned a cDNA encoding an embryonic stem cell transcriptional coactivator termed UTF1 from the mouse F9 teratocarcinoma cell line (Okuda, A., Fukushima, A., Nishimoto, M., Orimo, A., Yamagishi, T., Nabeshima, Y., Kuro-o, M., Nabeshima, Y., Boon, K., Keaveney, M., Stunnenberg, H.G., and Muramatsu, M. (1998) EMBO J. 17, 2019-2032). Here we have cloned a cDNA for human UTF1 and identified two highly conserved domains termed conserved domain (CD)1 and CD2. Human UTF1, like that of mouse, binds to ATF-2 and the mutagenesis analyses reveal that the leucine zipper motif within the CD2 of the UTF1 and metal binding motif of ATF-2 are involved in this interaction. The factor also binds to TATA-binding protein containing complex. By means of immunoprecipitation analysis, we mapped two domains which are independently able to bind to the complex. Importantly, both domains are located within the conserved domains (one in CD1 and the other in CD2). Furthermore, transient transfection analyses point out the importance of these domains for activating ATF-2. Thus, these results suggest that these two conserved domains identified here play important roles in activating specific transcription at least in part by supporting physical interaction between the upstream factor, ATF-2, and basal transcription machinery.

Activating Transcription Factor 2↗

UTF1, a novel transcriptional coactivator expressed in pluripotent embryonic stem cells and extra-embryonic cells.

We have obtained a novel transcriptional cofactor, termed undifferentiated embryonic cell transcription factor 1 (UTF1), from F9 embryonic carcinoma (EC) cells. This protein is expressed in EC and embryonic stem cells, as well as in germ line tissues, but could not be detected in any of the other adult mouse tissues tested. Furthermore, when EC cells are induced to differentiate, UTF1 expression is rapidly extinguished. In normal mouse embryos, UTF1 mRNA is present in the inner cell mass, the primitive ectoderm and the extra-embryonic tissues. During the primitive streak stage, the induction of mesodermal cells is accompanied by the down-regulation of UTF1 in the primitive ectoderm. However, its expression is maintained for up to 13.5 days post-coitum in the extra-embryonic tissue. Functionally, UTF1 boosts the level of transcription of the adenovirus E2A promoter. However, unlike the pluripotent cell-specific E1A-like activity, which requires the E2F sites of the E2A promoter for increased transcriptional activation, UTF1-mediated activation is dependent on the upstream ATF site of this promoter. This result indicates that UTF1 is not a major component of the E1A-like activity present in pluripotent embryonic cells. Further analyses revealed that UTF1 interacts not only with the activation domain of ATF-2, but also with the TFIID complex in vivo. Thus, UTF1 displays many of the hallmark characteristics expected for a tissue-specific transcriptional coactivator that works in early embryogenesis.

Activating Transcription Factor 2↗

Usefulness of enhanced insulin secretion during an oral glucose tolerance test as a predictor of restenosis after direct percutaneous transluminal coronary angioplasty during acute myocardial infarction in patients without diabetes mellitus.

To determine predictive factors of the development of restenosis after percutaneous transluminal coronary angioplasty (PTCA), 25 nondiabetic nonobese patients aged <80 years old and 57 consecutive patients with successful direct PTCA with acute myocardial infarction were subjected to a 75-g oral glucose tolerance test (OGTT) and underwent follow-up coronary angiography 4 months later. The relation between the development of restenosis (late loss index: the decrease in the absolute minimal lumen diameter [MLD] at follow-up coronary angiography divided by MLD measured 1 day after PTCA) and the results of OGTT together with basic patient characteristics like age, body mass index, plasma levels of cholesterol, triglycerides, and high-density lipoprotein cholesterol were analyzed. Spearman's rank correlation analysis revealed that neither age, body mass index, nor plasma lipids correlated with late loss index, but only insulin area (p = 0.041) and insulin area/glucose area (p = 0.038) significantly correlated with the development of restenosis; a stepwise multiple regression analysis revealed that the insulin area was the only independent predictor of restenosis (p = 0.019). These results suggest that enhanced insulin secretion in response to glucose plays an important role in the development of restenosis after direct PTCA in non-diabetic patients, which may be through the direct action of insulin on smooth muscle cells of the coronary artery. This study also suggests the importance of performing OGTT for patients undergoing PTCA for the prediction of the development of restenosis.

Aged↗

Comparison of genetic susceptibility to experimental allergic/immune-mediated blepharoconjunctivitis between Lewis and Fischer rats.

BACKGROUND: Fischer rats were less susceptible to experimental autoimmune uveoretinitis (EAU) than Lewis rats, although both strains have the same MHC molecules. The purpose of this study was to compare the susceptibility of experimental allergic/immune-mediated blepharoconjunctivitis (EAC) between these two strains. METHODS: Male Lewis and Fischer rats were immunized with either ovalbumin (OVA) or OVA peptide (OVA323-339) in complete Freund's adjuvant (CFA). Three weeks later, they were challenged with OVA by eye drops. Twenty-four hours later, after clinical evaluation, they were killed and eyes, blood and lymph nodes were harvested for histology, antibody titer and proliferation assay, cytokine production or flow cytometric analysis, respectively. RESULTS: Fischer rats developed mild EAC compared with Lewis rats. Cellular proliferative responses, IFN-gamma production of culture supernatant and serum IgG specific for OVA were basically the same between the two strains. The same OVA peptides were selected as immunodominant. Flow cytometric analysis demonstrated the same cellular profile of lymph node cells in the two strains. CONCLUSION: EAC in Fischer rats was milder than that in Lewis rats, although no apparent differences in immunological parameters between these two strains were detected. These data suggest that factors unrelated to immunological parameters may depend on the susceptibility of EAC.

Allergens↗

A new antitumor agent amrubicin induces cell growth inhibition by stabilizing topoisomerase II-DNA complex.

Amrubicin is a novel, completely synthetic 9-aminoanthracycline derivative. Amrubicin and its C-13 alcohol metabolite, amrubicinol, inhibited purified human DNA topoisomerase II (topo II). Compared with doxorubicin (DXR), amrubicin and amrubicinol induced extensive DNA-protein complex formation and double-strand DNA breaks in CCRF-CEM cells and KU-2 cells. In this study, we found that ICRF-193, a topo II catalytic inhibitor, antagonized both DNA-protein complex formation and double-strand DNA breaks induced by amrubicin and amrubicinol. Coordinately, cell growth inhibition induced by amrubicin and amrubicinol, but not that induced by DXR, was antagonized by ICRF-193. Taken together, these findings indicate that the cell growth-inhibitory effects of amrubicin and amrubicinol are due to DNA-protein complex formation followed by double-strand DNA breaks, which are mediated by topo II.

Anthracyclines↗

Analysis of effects of stimulation in vitro of ovalbumin primed lymph node cells on adoptive transfer of experimental immune mediated blepharoconjunctivitis in Lewis rats.

AIM: To analyse the role of stimulation in vitro of lymphocytes on the augmentation of experimental immune mediated blepharoconjunctivitis (EC, formerly EAC) in Lewis rats induced by adoptive transfer. METHODS: Two weeks after immunisation with ovalbumin (OVA), rat draining lymph nodes were collected and 50 x 10(6) cells were injected into naive syngeneic recipients either directly or after culture in vitro with OVA, concanavalin A (Con A), or purified protein derivative (PPD) for 3 days. Four days after injection the rats were topically challenged with OVA. 24 hours later, they were sacrificed and eyes and spleens were harvested for histology and proliferation assay. In some experiments, naive recipient rats were irradiated with 7 Gy gamma ray before transfer. The expression of adhesion molecules and cytokine profile of OVA primed lymph node cells were also investigated. RESULTS: Both infiltrated cell number and splenocyte proliferation in the recipients of stimulated cells were higher than those of unstimulated cells. In vitro stimulation with OVA or Con A induced a severe cellular infiltration, while stimulation with PPD did not. Irradiation markedly diminished cellular infiltration. Stimulation in vitro upregulated the CD4/CD8 ratio by four times and augmented expression of CD25, I-A, ICAM-1 molecules on OVA primed lymph node cells by about five times. IFN-gamma was detected in OVA primed cells by stimulation in vitro, while IL-4 mRNA was extinguished by stimulation in vitro. CONCLUSIONS: Augmentation of EC by stimulation in vitro of transferred lymphocytes might depend on the upregulation of expression of cell surface molecules and cytokine shift as well as augmented antigen specificity.

Adoptive Transfer↗

Transcriptional regulation of rat calbindin expression during development determined by bacterially expressed protein.

Calbindin-D9k expression in intestinal mucosal cells reveals a specific pattern during development in rats. It shows a low basal level in suckling and adult rats, but after weaning at 21 d of age, increases to three times that of the basal level for several days only, around 24 d. We attempted to clarify whether the regulation of developmental change was at the transcriptional or post-transcriptional level. The calbindin-D9k protein and mRNA concentrations during pre- and postweaned development were determined by Western blot and Northern blot analysis, respectively, and compared with calcium binding activity by 45Ca. For Western blot analysis, a corresponding antibody was raised in rabbit using a bacterially expressed fusion protein, glutathione S-transferase (GST, EC 2.5.1.18), and calbindin-D9k. Calbindin-D9k cDNA was linked to a GST gene within a molecule of vector plasmid and a fusion protein was expressed in Escherichia coli. There were significant (p < 0.001) correlations between calbindin-D9k protein, mRNA concentrations and calcium-binding activity: r = 0.90 for protein vs. mRNA, r = 0.93 for protein vs. binding activity and r = 0.95 for mRNA vs. binding activity. These results indicate that calbindin-D9k expression during postnatal development is regulated at the transcriptional level.

Animals↗

[Unexpected anuria during Miles' operation in a renal-transplant patient].

We report a case of 33-yr-old-male after orthotopic renal transplantation 18 years ago, presenting with sudden anuria during Miles' operation. This anuria was caused by temporal compression of the transplanted kidney by retractor, neither by acute renal failure, the rejection nor the damage of the ureter by the surgical procedure. This case indicates that in the anesthetic management after renal transplantation, we have to be careful about renal dysfunction due to surgical procedure or positioning, in addition to side effects and pharmacokinetics of drugs used perioperatively.

Adult↗

Characterization of the immunopathogenic responses to ovalbumin peptide 323-339 in experimental immune-mediated blepharoconjunctivitis in Lewis rats.

PURPOSE: We recently reported the essential role of cellular immunity on the induction of experimental immune-mediated blepharoconjunctivitis (EC, formerly EAC) by using ovalbumin (OVA) as a model antigen in Lewis rats. The purpose of this study was to investigate the possible induction of EC by immunization with an OVA peptide (OVA 323-339). METHODS: Lewis rats were immunized with various doses of OVA or OVA 323-339 in complete Freund's adjuvant. Three weeks later they were challenged with OVA or OVA 323-339 by eye drops; 24 h after challenge, eyes including lids, lymph nodes and blood were harvested after clinical evaluation. An OVA 323-339-specific cell line (S816) was established by periodical stimulation with this peptide. Pathogenicity of S816 was tested by adoptive transfer of S816 into syngeneic recipient rats after challenge with OVA or OVA 323-339. RESULTS: All rats immunized with OVA 323-339 developed EC after challenge with OVA or OVA 323-339. Rats immunized with OVA 323-339 at doses as low as 0.01 microg had severe clinical scores. OVA-primed rats also developed EC after challenge with OVA 323-339. OVA-primed lymph node cells responded to OVA but not to OVA 323-339. OVA 323-339-primed lymph node cells responded to OVA 323-339 but not to OVA and produced IFN-gamma by stimulation with either OVA or OVA 323-339 (three- to fourfold more than with OVA-primed lymph node cells). Recipient rats of S816 developed severe EC after challenge with either OVA or OVA 323-339. CONCLUSION: OVA 323-339 was identified as a potent pathogenic peptide in EC.

Adoptive Transfer↗

Expression of ocular autoantigens in the mouse thymus.

UNLABELLED: PURPOSE. The occurrence of eye diseases of autoimmune nature, as well as experimental models of these diseases, has been attributed to the sequestration of ocular antigens from the immune system, that prevents the development of tolerance against these antigens. Here, we tested this assertion by examining whether transcripts of certain ocular antigens are constitutively expressed in the thymus, the site of central tolerance induction. METHOD: RNA was isolated from the eyes and thymi of two mouse strains and analyzed for the expression of genes encoding four retinal and three lens proteins by reverse transcribed-polymerase chain reaction. Southern blot and DNA sequence analyses. RESULTS: We detected gene transcripts of S-Antigen (S-Ag), interphotoreceptor retinoid-binding protein, opsin, recoverin, lens major intrinsic protein (MIP), alphaA-, alphaA(-ins)- and gamma-crystallins in the thymi of BALB/c and FVB/N mouse strains. DNA sequence analysis of the thymic MIP and S-Ag transcripts confirmed their identity to the lens and retinal proteins, respectively. CONCLUSIONS: Our results reveal that transcripts of several ocular-specific proteins are expressed in the thymus and suggest that the commonly held view that ocular-specific antigens are sequestered from the immune system should be modified.

Animals↗

Immunotolerance against a foreign antigen transgenically expressed in the lens.

PURPOSE: To extend our knowledge concerning immunotolerance against autologous lens crystallins, transgenic (Tg) mice that express a foreign antigen in their lens were generated, and the immune response against the antigen in these mice was analyzed. METHODS: Conventional techniques were used to generate lines of Tg mice that express soluble (S-) or membrane-bound (M-) hen egg lysozyme (HEL) under the control of the alphaA-crystallin promoter. The presence of HEL in various organs was determined by the particle concentration fluorescence immunoassay (PCFIA), and reverse transcription-polymerase chain reaction technique was used to detect mRNA transcripts of the molecule. To examine the development of immunity (or tolerance), Tg mice and their wild-type controls were immunized with HEL (25 microg) in Freund's complete adjuvant and 14 days later were tested for immune response against the antigen. Cellular immunity was measured by the lymphocyte proliferation assay and cytokine production, and humoral immunity was determined by enzyme-linked immunosorbent assay. RESULTS: Eyes of the high copy number M-HEL Tg mice were dystrophic, with disrupted lens, whereas no morphologic changes were detected in the eyes of the other Tg mouse lines. All Tg mice exhibited tolerance to HEL by their cellular and humoral immune compartments. The state of immunotolerance to HEL was retained in the Tg mice for as long as 10 months after removal of the main depot of this protein, by enucleation. Measurable amounts of HEL were found in the eyes of all Tg mice, but the protein could not be detected in the serum or in other organs by the sensitive PCFIA (with a threshold of 1 ng/ml). Yet, HEL mRNA was found in the thymus of the Tg mice, suggesting that minute amounts of the protein are expressed in this organ. CONCLUSIONS: The unresponsiveness to HEL in the Tg mice seems to be due to a "central" mechanism of tolerance, mediated by a minuscule amount of HEL in the thymus. Conversely, the much larger amounts of HEL in the peripheral depot, the eyes, play a minor role if any in the tolerogenic process. It is further proposed that a similar mechanism of central tolerance is responsible for the immunotolerance against autologous lens crystallins.

Animals↗

Isolation of a cDNA encoding a widely expressed novel zinc finger protein with the LeR and KRAB-A domains.

We have isolated a human cDNA clone representing a novel human gene. The predicted 683-amino-acid protein, designated FPM315, contains nine C2H2-type zinc finger motifs and two regions homologous to the LeR domain, a finger-associated structural domain, and the A element of the Kruppel-associated box (KRAB) domain involved in transcriptional repression. The FPM315 mRNAs were expressed in all human tissues so far examined. A cross-species genomic hybridization indicates that the FPM315 gene is highly conserved among eukaryotes. These data suggest that FPM315 might play an important role in basic cellular processes.

Amino Acid Sequence↗

The role of cellular immunity both in the induction and effector phases of experimental allergic blepharoconjunctivitis (EAC) in rats.

In allergic conjunctivitis, the early phase reaction has been studied extensively both in humans and animals. Although cellular infiltration is the main feature of the late phase reaction, the role of cellular immunity remains unclear. The purpose of this study was to elucidate the role of cellular immunity both in the induction and effector phases of experimental allergic blepharoconjunctivitis (EAC). To analyse the involvement of cellular immunity in the induction phase, 6-8-week-old male Lewis rats were immunized with ovalbumin (OVA) emulsified with complete Freund's adjuvant (CFA), incomplete Freund's adjuvant (IFA), TiterMaxR (TM), aluminum hydroxide [Al(OH)3], or without any adjuvant. Three weeks after immunization, the rats were challenged with OVA by eye drops, and 24 hr later they were euthanized and their eyes, including the lids, blood, and lymph nodes were harvested for analysis of disease and immune responses. The results indicated that adjuvants were necessary to induce disease as well as both cellular and humoral immunity. Al(OH)3, CFA and TM induced stronger disease and cellular immunity than IFA. The intensity of disease correlated with that of cellular immunity. To further investigate the involvement of cellular immunity in EAC, lymph node cells collected from immunized rats were adoptively transferred into naive syngeneic recipients that were challenged 4 days later with OVA. EAC developed in the recipients of lymph node cells that were also stimulated in culture with OVA. These recipient rats developed cellular infiltration in the lid and conjunctiva, in a dose-dependent manner. These results suggest that cellular immunity played a major role in the development of EAC, both in the induction and effector phases.

Adjuvants, Immunologic↗

Histopathologic features of neovascularization in sickle cell retinopathy.

PURPOSE: To examine the histopathologic and morphometric features of neovascular lesions in human proliferative sickle cell retinopathy. METHODS: Postmortem ocular tissue was obtained from three subjects (aged 20, 28, and 40 years) with SS hemoglobinopathy and prepared for adenosine diphosphatase flat-embedding. Morphometric analysis was performed before serial sectioning. RESULTS: Numerous active and autoinfarcted lesions were found that represented virtually all stages in the life cycle of preretinal neovascularization. These formations ranged from single small loops extending from arteries and veins along the retinal surface to the typical complex, elevated sea fan formations. Sea fans developed at hairpin loops and at arteriovenous crossings. There was an average of 5.6 connections between sea fans and retinal vessels; of these, 45% were arteriolar, 52.5% were venular, and 2.6% were at the capillary level. Six of eight sea fans were located at arteriovenous crossings. Autoinfarction appeared to occur initially within the sea fan capillaries. The average height of sea fans was 123 microns above the retinal surface. CONCLUSIONS: Preretinal neovascularization in sickle cell retinopathy can arise from both the arterial and venous sides of the retinal vasculature and can assume a variety of morphologic configurations. Multiple feeding arterioles and draining venules are common, and autoinfarction appears to occur initially at the preretinal capillary level rather than at feeding arterioles. Arteriovenous crossings may be a preferential site for sea fan development.

Adult↗

Protective effect of mucosal administration of recombinant human macrophage colony-stimulating factor (rhM-CSF) on mucosal infection of Sendai virus in mice.

We investigated the protection confered by the mucosal administration of recombinant human macrophage colony-stimulating factor (rhM-CSF) against mucosal infection of Sendai virus in mice. In an experimental infection model using Sendai virus, an intranasal (i.n.) administration of rhM-CSF (20 micrograms per mouse) 2 days before injection induced significant protection against a lethal infection of this virus. Also, its antiviral activity was dependent upon the dose of rhM-CSF. However, a subcutaneous (s.c.) administration of rhM-CSF with an effective dose (20 micrograms per mouse) i.n. did not confer protection. In a time course analysis of virus growth in the lungs, mice given rhM-CSF. i.n. significantly inhibited the early period of infection, compared with the untreated mice. Moreover, the level of interferon-gamma (IFN-gamma) in lung wash fluids from the rhM-CSF-treated mice was higher than that of the untreated mice. These results suggested that the mucosal (i.n.), but not the systemic (s.c.) administration of rhM-CSF augments host resistance against mucosal infection with Sendai virus, and that its prophylactic activity is related to growth inhibition of the virus and enhanced IFN-gamma secretion in the lungs.

Animals↗

An HTLV-I carrier with Graves' disease followed by uveitis: isolation of HTLV-I from thyroid tissue.

We report a long-term (14-year) follow-up of a human T-lymphotropic virus type I (HTLV-I)-infected male who was successively afflicted with Graves' disease followed by uveitis. HTLV-I proviral DNA was detected by polymerase chain reaction in the thyroid tissue and HTLV-I was isolated from thyroid tissue by coculture with peripheral blood lymphocytes from an HTLV-I-uninfected healthy female. This case study supports a close relationship between Graves' disease and uveitis in an HTLV-I carrier.

Adult↗

Functional transplant of megabase human immunoglobulin loci recapitulates human antibody response in mice.

We constructed two megabase-sized YACs containing large contiguous fragments of the human heavy and kappa (kappa) light chain immunoglobulin (Ig) loci in nearly germline configuration, including approximately 66 VH and 32 V kappa genes. We introduced these YACs into Ig-inactivated mice and observed human antibody production which closely resembled that seen in humans in all respects, including gene rearrangement, assembly, and repertoire. Diverse Ig gene usage together with somatic hypermutation enables the mice to generate high affinity fully human antibodies to multiple antigens, including human proteins. Our results underscore the importance of the large Ig fragments with multiple V genes for restoration of a normal humoral immune response. These mice are likely to be a valuable tool for the generation of therapeutic antibodies.

Amino Acid Sequence↗

Permissive recognition of immunodominant determinants of the retinal S-antigen in different rat strains, primates and humans.

The majority of antigenic peptides exhibit restriction in their interaction with the MHC molecules on antigen-presenting cells of different haplotypes. Certain peptides, however, are "permissive': they bind strongly to different MHC molecules and are selected as the immunodominant epitopes by animals using these MHC gene products. Here we show for the first time that several peptides from four regions of the sequence of human S-antigen (H-SAg), a retinal-specific protein, demonstrate high levels of permissiveness. Each of these peptides was found to be immunodominant in at least some of four inbred rat strains and five cynomolgus monkeys, immunized with whole H-SAg. Moreover, some of these peptides were recognized by lymphocytes from four normal controls and four patients with uveitis who responded against the H-SAg molecule. On the other hand, the permissive peptides stimulated marginal or no response in cultures of Lewis rats injected with adjuvant alone, or rat and human cell lines specific to other antigens, thus demonstrating that these peptides do not carry any non-specific mitogenic activity. One peptide, 29, which was found immunodominant in the monkeys, the uveitis patients and Lewis rats, is highly immunopathogenic in this rat strain. No good correlation between immunodominance and immunopathogenicity was found with other H-SAg peptides. The finding of cross-species permissiveness among peptides of H-SAg and similar observations with myelin proteins suggest that permissiveness could be quite prevalent among peptides of immunopathogenic antigens.

Adult↗