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Biomedical subjects

I Takakura

Publications and source records attributed to I Takakura.

At least 19 recordsLinked to original sources
PubMed1999

An in vivo model of human skin acute graft-versus-host disease: transplantation of cultured human epidermal cells and dermal fibroblasts with human lymphocytes into SCID mice.

The ability of mixed epidermal cell-lymphocyte reactions to detect allogeneic reactivities in an in vivo model was investigated by developing an in vivo model of acute graft-versus-host disease (GVHD), using SCID mice with a C.B-17 background in which human skin structures were generated by transplantation of cultured human epidermal cells (HEC) with dermal fibroblasts (HDFC). Suspensions containing cultured HEC and HDFC from a single donor were mixed with autologous peripheral blood mononuclear cells (PBMNC) or with PBMNC from unrelated individuals, and were injected into the flanks of C.B-17-SCID mice. Ten and 21 days after injection, subcutaneous nodules generated in the mice were examined histologically and immunohistochemically. Cystic structures developing after injection of HEC and HDFC without human PBMNC showed normal epidermislike tissue. Human skin generated in SCID mice injected with HEC and HDFC with auto-PBMNC showed no graft-versus-host reaction (GVHR) histologically, whereas those mice injected with PBMNC from siblings that shared an HLA haplotype showed mild GVHR. Human skin in SCID mice injected with HEC and HDFC with histoincompatible unrelated PBMNC showed moderate to severe GVHR. The severity of GVHR paralleled the dose of unrelated PBMNC, and GVHR was prevented by peroral treatment with cyclosporine A. Immunohistochemically, inflammatory cells infiltrating human cutaneous tissue formed in the SCID mice were stained by an anti-human CD45RO antibody that reacts with human T cells but not with murine lymphocytes, and most T cells were stained by an anti-human CD8 antibody recognizing HLA class I antigens. These findings are similar to those in clinical skin graft-versus host disease (GVHD) observed in patients undergoing allogeneic bone marrow transplantation. This experimental system should be useful as an in vivo model of human skin GVHD.

Animals↗
PubMed1998

Human monoclonal anti-HCMV neutralizing antibody from phage display libraries.

Human cytomegalovirus (HCMV) infection in immunocompromised patients causes considerable morbidity and mortality. Although ganciclovir prophylaxis reduces the incidence of HCMV disease, severe side effects raise serious problems. Thus, the development of new strategies for prophylaxis are clearly needed, and human monoclonal antibodies offer a potential alternative. We describe the cloning, using the phage display system, of a recombinant human Fab fragment against HCMV. A phage display library with 4 x 10(6) clones was panned three times against lysates of HCMV-infected cells, and screened by ELISA. Of six antigen-binding clones, one monoclonal antibody reacted strongly to HCMV. In immunostaining analysis, this Fab was able to stain HCMV-infected cells from 24 h post-infection (pi) through to 96 h pi, but not at 6 h pi. In the presence of cytosine arabinoside, HCMV-infected cells were not stained, even at 24 h pi. These results indicate that an HCMV protein that was recognized by the Fab was synthesized in the late phase of infection. In addition, this Fab exhibited neutralizing activity: at 1 microg/ml it reduced HCMV plaque formation by 50%. The Fab was able to neutralize three HCMV strains, but it did not neutralize HSV-1 or -2 infection.

Amino Acid Sequence↗
PubMed1998

A simple and efficient purification of transduced cells by using green fluorescent protein gene as a selection marker.

BACKGROUND: Simple and efficient method for the selection of transduced cells would greatly facilitate the clinical utilization of retrovirus vectors. We developed a therapeutic bicistronic retrovirus vector for Gaucher disease, MFG-GC-GFP, which contains the human glucocerebrosidase (GC) gene and the green fluorescent protein (GFP) gene of the jellyfish Aequorea victoria as a vital selection marker, and investigated its applicability as gene therapy for Gaucher disease. METHODS AND RESULTS: A packaging cell line, GP + envAM12, was transfected with MFG-GC-GFP and, thus, produced a high titer recombinant virus (1.0 x 10(6) c.f.u./mL) in the culture supernatant. The expression level of GFP was correlated with the virus production in cells. The recombinant virus infected skin fibroblasts from a Gaucher patient and a sorted fraction of the cells expressing GFP by flow cytometry exhibited almost a six-fold higher activity of GC than normal fibroblasts. CONCLUSIONS: These data indicate that MFG-GC-GFP enables the one-step purification of a transduced fraction of target cells and is, therefore, considered to be a useful therapeutic vector for the experimental gene therapy of Gaucher disease.

Animals↗
PubMed1998

[Clinical and bacteriological studies on panipenem/betamipron in pediatrics. Kanagawa Research Group for Infectious Diseases of Children].

Following its introduction into the market, PAPM/BP (panipenem/betamipron) was clinically studied in 188 evaluable cases out of 207 cases primarily of respiratory infectious diseases treated at the pediatric departments of 15 hospitals. In the clinical evaluation, the drug proved effective in three of three cases of sepsis; three of three cases of suppurative meningitis; nine of ten cases of laryngopharyngitis, six of seven cases of tonsillitis, 56 of 63 cases of acute bronchitis, 90 of 98 cases of pneumonia, and one of one case of phyothorax, all of which are respiratory infectious diseases; one of one case of secondary infection of a chronic respiratory disease; and two of two cases of lymphadenitis, which is a disease of the soft dermal structure. The overall efficacy rate was 91.0% (171/188 cases). In the bacteriological study, Gram-positive bacteria were eliminated in five of five strains of S. aureus, 30 of 31 strains of S. pneumoniae (96.8%), and three of three strains of S. pyogenes. Gramnegative bacteria were eliminated in 15 of 17 strains of H. influenzae (88.2%), three of four strains of M. catarrhalis, and two of two strains of K. pneumoniae. The overall elimination rate was 92.1% (70/76 strains). In the 23 strains of S. pneumoniae that were examined, penicillin-resistant strains accounted for 56.5%, showing an elimination rate of 100%. No serious adverse effects were observed, and the incidence of adverse effects was 1.45%. As for abnormalities in laboratory tests, levels of GOT and GPT increased in eight cases (3.88%), LDH increased in one case (0.48%), and neutropenia occurred in one case (0.51%). These results suggest that PAMP/BP could be considered the first choice in the treatment of infectious diseases in pediatrics, due to its effectiveness and high level of safety.

Adolescent↗
PubMed1997

Fatal interstitial pulmonary disease in a patient with dyskeratosis congenita after allogeneic bone marrow transplantation.

Chronic restrictive lung disease in a 9-year-old boy with dyskeratosis congenita (DC) 7 years after allogeneic bone marrow transplantation (BMT) is described. When he was 1 year and 10 months old, severe aplastic anemia developed. He received a marrow transplant from his HLA serologically identical, but HLA-DP mismatched brother. He developed grade II acute graft-versus-host disease (GVHD) and thereafter chronic GVHD of progressive type, and was treated with both prednisolone and azathioprine resulting in clinical improvement. Thereafter he complained of dyspnea, and bilateral noncircumscribed interstitial shadows on chest CT scan were present. His pulmonary function showed restrictive changes. Prednisolone was not effective and he died of respiratory failure. Post-mortem examination confirmed interstitial fibrosis, lymphocytic infiltration of the bronchioles and alveoli with luminal fibrosis. There was no evidence of chronic GVHD in the skin and the liver. These findings raise the possibility that this pulmonary complication was associated with DC itself.

Anemia, Aplastic↗
PubMed1995

Bispecific antibody-mediated cytotoxicity by CD4+ and CD8(+)-activated T cells generated from leukemia patients after allogeneic bone marrow transplantation.

The F(ab')2 bispecific antibody (BSAb) was prepared from anti-CD3 moAb and anti-CD10 moAb. The BSAb could react with both CD3+ T cells and CD10+ leukemia cells and triggered T cell-mediated cytotoxicity. To apply the BSAb to prevention of leukemic relapse after BMT, we investigated the generation of both CD4+ and CD8+ anti-tumor effector T cells from patient's PBMC 14 days after BMT. Neither CD4+ T cells nor CD8+ T cells, which were activated with immobilized anti-CD3 moAb plus IL-2, could lyse CD10+ leukemia cells by themselves, but they showed augmented cytotoxicity against CD10+ leukemia cells by targeting with anti-CD3 x anti-CD10 BSAb. Moreover, the activated CD4+ T cells were demonstrated to produce IL-2 and IFN-gamma when they were cultured with CD10+ leukemia cells in the presence of the BSAb. The BSAb-mediated cytotoxicity of activated T cells was demonstrated not only against the recipient leukemia cells but also against third party leukemia cells. These results suggested that anti-CD3 x anti-CD10 BSAb might be a good tool to prevent relapse after BMT in combination with activated CD4+ T cells and CD8+ T cells.

Antibodies, Monoclonal↗
PubMed1994

Changes in hypothalamic-pituitary function following bone marrow transplantation in children.

Patients who undergo bone marrow transplantation (BMT) frequently experience impaired pituitary function, but precise assessment using repeated provocative tests has not been described. We studied 32 children (16 boys) who had BMT after receiving preparative irradiation. Assessment of pituitary function was performed by infusing insulin, luteinizing hormone-releasing hormone (LHRH), and thyrotropin-releasing hormone (TRH) on several occasions at various intervals during the follow-up period. Serum free thyroxine (FT4) and thyrotropin (TSH) levels tended to be low during the early period following BMT. Serum FT4 concentrations reverted to the low-normal range 1 year after transplant, and eight of 29 patients had subnormal and delayed TSH response to TRH consecutively. No children showed overt hypothyroidism. Basal and peak serum gonadotropin levels in response to LHRH were elevated in the patients who had received transplant around the time of puberty. Leydig cell function assessed by human chorionic gonadotropin test was normal. Three girls experienced menarche, and one male patient fathered a normal boy 7 years after BMT. Pituitary-adrenal function and prolactin secretion were not affected. A high incidence of transient hypothyroidism which did not require replacement therapy and gonadal failure among pubertal children were observed. Shielding of gonads should be attempted, if possible, at the time of preparative irradiation to prevent resultant hypogonadism.

Adolescent↗
PubMed1993

Rapid detection of Mycoplasma pneumoniae in clinical samples by the polymerase chain reaction.

A DNA amplification method was used to detect Mycoplasma pneumoniae in clinical samples. M. pneumoniae 16S ribosomal RNA gene sequences were selected as the amplification target region. The polymerase chain reaction (PCR) with purified DNA fragments as templates yielded an expected 88-bp fragment from M. pneumoniae but not from other Mycoplasma spp. nor from any of the other bacteria assayed. With this method, the 88-bp product specific for M. pneumoniae could be obtained from a minimum of 0.05 pg of M. pneumoniae DNA. Subsequently this PCR technique was used for the detection of M. pneumoniae in throat-swab samples. Twenty-two of 30 culture-positive clinical samples gave positive results in the PCR test. Thirty-two culture-negative clinical samples and 33 samples from healthy volunteers, of which only one was culture-positive, gave negative results in the same PCR test. This PCR method is useful for the direct detection of M. pneumoniae in clinical samples.

Base Sequence↗
PubMed1992

Accidents in childhood. Review of cases in the emergency room and hospitalized cases.

Accident mortality in childhood is a big problem not only in Japan but also in many other countries. We have reviewed our experience of 4,502 patients below 18 years of age who visited our emergency room in the fiscal year 1990. The number of cases of accidents other than traffic accidents was 243 and was almost double the 131 children involved in traffic accidents. Children with ordinary injuries (trauma) were excluded from accident patients. The most common non-traffic accident in childhood was foreign body ingestion or inhalation. The gastrointestinal tract was the most common site of foreign body ingestion or inhalation. Forty-two children with bronchial foreign bodies and 38 cases of near-drowning who were admitted to our hospital from 1975 to 1991 were also studies. Among the bronchial foreign bodies, we had a high rate of peanut inhalation. Foodstuffs including peanut accounted for more than 80% of the bronchial foreign bodies. Among the 38 near-drowning cases, we had five fatal cases, three cases were severe neurological sequelae and 30 intact survivals. Bathtubs at home were the most common site of near-drowning, particularly for young children.

Accidents↗
PubMed1988

Mycoplasmal pneumonia--review of 202 hospitalized cases in Tokai University Hospital from 1975 to 1987.

Characteristic of patients with mycoplasmal pneumonia has been stated reviewing 124 children and 78 adults who were hospitalized in Tokai University Hospital during the period from 1975 to 1987. Differences in clinical features between pediatric and adult cases have also been stated. As another epidemic may appear in this year, 1988, because the last previous epidemic was four years ago, it may be worth it to stress the importance of epidemiological and clinical knowledge of the disease.

Adolescent↗
PubMed1985

Correlation of the modified scratch test with the radioallergosorbent test (RAST) in atopic children.

The usefulness of the modified scratch test in predicting clinical allergy and its correlation with the RAST were studied in 83 atopic children. A total of 423 scratch tests were compared with the same number of RAST. Percentage agreements between the two tests for individual allergens ranged from 87.5% (milk) to 50% (cat epithelium). The RAST showed more positive results only for the house dust allergen. Both RAST and scratch tests were not indicative of clinical allergy in the skin and gastrointestinal tract. It was concluded that the modified scratch test may give useful information and remain as one of the routine investigative procedures in pediatric allergy.

Adolescent↗
PubMed1982

HLA-DR antigens and the rubella-specific immune response in man.

Several genetic markers, HLA-A, B and DR antigens, Gm and Km types, and ABO blood types, were studied on 78 rubella seronegative schoolgirls immunized with "TO336" rubella vaccine. A marked association was found between an HLA haplotype, HLA-Aw24-Bw52-DRHO, and the low antibody responsiveness to rubella virus. The association with the DR antigen was thought to be primary to those with the HLA-A or B antigens, suggesting that the gene(s) controlling the low responsiveness to rubella might be located near the HLA-DR locus in the human 6th chromosome. There was no statistically significant association between Gm, Km or ABO blood types and the rubella specific immune responsiveness as far as the primary in vivo antibody response was concerned.

Antibodies, Viral↗