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Biomedical subjects

M Tateno

Publications and source records attributed to M Tateno.

At least 73 records · Page 4Linked to original sources
PubMed1994

The novel ion pump rhodopsins from Haloarcula form a family independent from both the bacteriorhodopsin and archaerhodopsin families/tribes.

Extreme halophiles newly collected from Argentine salt flats were characterized, in one of which, Haloarcula (sp. arg-1), light-driven retinal protein ion pumps were found. The proton pump, cruxrhodopsin-1, shows amino acid sequence homologies of 52% to bacteriorhodopsin and 48% to archaerhodopsin-1. The anion pump, cruxhalorhodopsin-1, identified partially as a 394bp polymerase chain reaction product, shows homologies of 70% to halorhodopsin, and 72% to pharaonis halorhodopsin. The ion pumps (and possibly sensors still to be found) in Haloarcula sp. arg-1, which constitute the cruxrhodopsin-1 family, are distinct from the bacteriorhodopsin and the archaerhodopsin families/tribes.

Amino Acid Sequence↗
PubMed1994

Expression of an endogenous retroviral gene product in human placenta.

To investigate the presence and potential pathophysiological role of endogenous retroviruses in humans, we prepared a recombinant protein using clone 4-I, a proviral sequence. DNA fragments containing the env region of clone 4-I were subcloned into a prokaryotic expression vector (pET3), and 2 fusion proteins, SU413 and SU415, were then expressed in Escherichia coli after treatment with isopropyl-beta-thiogalactopyranoside (IPTG). By sonicating lysates of the transformed E. coli, the recombinant protein SU413 was successfully separated from the native bacterial components, and was used to raise an antiserum in rabbits. In immunoblot analysis, this antiserum specifically recognized the recombinant protein, but did not react with other components of E. coli. This antiserum was then used for an immunofluorescence study of human placenta, in which the env gene transcript has been reported. As a result, the anti-SU413 serum detected substances in syncytiotrophoblasts and vascular endothelia from a human placenta. No such reactivity was detected in human kidney or human liver. Immunoblot analysis revealed that this antiserum reacted to a single molecule of 38-kDa in placenta, and its reactivity was reduced by the antiserum absorbed with SU413 antigen. These findings suggest that human placental syncytiotrophoblasts and vascular endothelia preferentially express a molecule encoded by human endogenous retrovirus clone 4-I.

Animals↗
PubMed1994

Hashimoto thyroiditis, distal renal tubular acidosis, pernicious anaemia and encephalopathy: a rare combination of auto-immune disorders in a 12-year-old girl.

A case of a 12-year-old girl with a multiple auto-immune disorder is reported. She showed Hashimoto thyroiditis which subsequently developed to hashitoxicosis and distal renal tubular acidosis at 5 years of age, pernicious anaemia at the age of 9 and severe encephalopathy at the age of 12. Laboratory studies revealed very high titres of anti-microsomal and anti-thyroglobulin antibodies and positive gastric parietal cell antibody. As to the encephalopathy, positive oligoclonal IgG bands and high values of IgG index and IgG synthesis ratio in CSF were observed with aggravation of her neurological symptoms. High-dose steroid therapy was effective toward the encephalopathy. Paediatricians should pay careful attention to patients with Hashimoto thyroiditis for association with other autoimmune disorders.

Acidosis, Renal Tubular↗
PubMed1993

Increased IgE level as a marker of host-versus-graft disease: inhibition of this HVGD with a monoclonal antibody to IL-4.

BALB/c mice injected at birth with (BALB/c x C57BL/6)F1 hybrid spleen cells developed host versus graft disease (HVGD) with immunological features, such as various autoantibodies, immune complex nephritis, hepatosplenomegaly, and malignant lymphomas. In addition we found that the increased IgE levels correlated strongly with the histological grades or stages of the liver disease. In the sera of mice with HVGD and liver alterations, anti-smooth muscle antibodies (ASMA) and anti-nuclear antibodies (ANA) were detected. The subclass of ASMA was IgG1, whereas the subclasses of ANA were IgG1, IgG2a, and IgG2b. When the recipient BALB/c mice were injected at birth and at Day 3 in addition also with monoclonal anti-IL-4 antibody 11B11, the increase of IgE and IgG1 was markedly reduced and the liver disease was drastically prevented. These observations suggest that IL-4 plays an important role in the initiation of the immunoregulatory function or pathogenesis of the allogeneic effects and that the monoclonal anti-IL-4 antibody 11B11 prevents the immunodysfunctions and the autoimmune hepatopathy in mice with HVGD. The increased IgE level in the serum is a good marker of HVGD.

Animals↗
PubMed1993

Clinical evaluation of thallium-201 SPECT in supratentorial gliomas: relationship to histologic grade, prognosis and proliferative activities.

We performed 201Tl SPECT and cell kinetic studies on 28 presurgical patients with supratentorial gliomas by administering bromodeoxyuridine (BUdR). All patients had surgery and had follow-up for more than 25 mo. In patients with grade IV glioma (198.1% +/- 32.8%, n = 10), the 201Tl index, expressed as the count rate of the tumor site to the count rate over the contralateral normal region, was significantly higher than that in patients with grade III glioma (140.5% +/- 15.1%, n = 4, p < 0.01) or low-grade glioma (104.1% +/- 22.6%, n = 14, p < 0.001). A significant correlation was observed between the 201Tl index and BUdR-positive cells in excised tumor specimens (r = 0.67, p < 0.001). The 201Tl index of the 12 patients who died was higher than those who survived (173.2% versus 122.4%, p < 0.01). These results show the clinical utility of 201Tl brain SPECT in imaging supratentorial glioma and that the 201Tl index is representative of proliferative activity of the tumor.

Adult↗
PubMed1992

A rat model of human T lymphocyte virus type I (HTLV-I) infection. 1. Humoral antibody response, provirus integration, and HTLV-I-associated myelopathy/tropical spastic paraparesis-like myelopathy in seronegative HTLV-I carrier rats.

Human T lymphocyte virus type I (HTLV-I) can be transmitted into several inbred strains of newborn and adult rats by inoculating newly established HTLV-I-immortalized rat T cell lines or the human T cell line MT-2. The transmission efficiency exceeds 80%, regardless of strain differences or the age at transmission. The production of anti-HTLV-I antibodies significantly differs among the strains and depends on the age at the time of transmission. Rats neonatally inoculated with HTLV-I-positive rat or human cells generally become seronegative HTLV-I carriers throughout their lives, whereas adult rats inoculated with HTLV-I-positive cells at 16 wk of age become seropositive HTLV-I carriers. The HTLV-I provirus genome is present in almost all organs, regardless of whether the carriers are seronegative or seropositive. According to antibody titers to HTLV-I, there are three groups of inbred rat strains: ACI, F344, and SDJ (high responders); WKA, BUF, and LEJ (intermediate responders); and LEW (low responder). Three of three 16-mo-old seronegative HTLV-I carrier rats of the WKA strain developed spastic paraparesis of the hind legs. Neuropathological examinations revealed that the lesions were confined primarily to the lateral and anterior funiculi of the spinal cord. Both myelin and axons were extensively damaged in a symmetrical fashion, and infiltration with massive foamy macrophages was evident. The most severe lesions were at levels of the thoracic cord and continued from the cervical to the lumbar area. These histopathological features as well as clinical symptoms largely parallel findings in humans with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). These HTLV-I carrier rats, in particular the WKA rats described above, can serve as a useful animal model for investigating virus-host interactions in the etiopathogenesis of HTLV-I-related immunological diseases, particularly HAM/TSP.

Aging↗
PubMed1992

Transient unilateral reverse ventilation/perfusion mismatch in a patient with lung cancer.

The authors report a transient, unilateral reverse ventilation/perfusion (V/P) mismatch in a patient with squamous cell lung cancer. The right lung was well perfused but not ventilated (unilateral reverse V/P mismatch). However, lung imaging performed 3 days later demonstrated the absence of both perfusion and ventilation (V/P match). Reverse V/P mismatch may be a transient process.

Carcinoma, Squamous Cell↗
PubMed1992

Phenotypic progression of a rat lymphoid cell line immortalized by human T-lymphotropic virus type I to induce lymphoma/leukemia-like disease in rats.

Rat lymphoid cells, TARS-1, immortalized by coculture with adult T-cell leukemia cells, were intraperitoneally injected into 65 newborn, inbred WKAH/Hkm rats. In most of the rats, tumor nodules were discernible 7 to 15 days after transplantation but were completely rejected within 5 to 6 weeks. Two rats with no tumor nodules exhibited gait disturbances and paralysis of the hind legs 3 to 4 weeks after transplantation. Histological and hematological examinations revealed that a lymphoma/leukemia-like disease had developed in one of the two rats, and the T-lymphoid cell line WLeuk-1 was established from peripheral blood mononuclear cells from this rat. When the WLeuk-1 cells were transplanted into newborn WKAH/Hkm rats, the animals died of a lymphoma/leukemia-like disease within several weeks after transplantation, in contrast to their rejection of the TARS-1 cells. Southern blot and karyotype analyses revealed that WLeuk-1 cells had retained the marker chromosomes and human T-lymphotropic virus type I (HTLV-I) integration patterns of the parent cell line, TARS-1. The additional specific chromosome abnormalities 3p+,t (12;13), and Xq+ were found in the WLeuk-1 cells. Moreover, the expression of HTLV-I structural proteins was slightly depressed in WLeuk-1 cells, while that of the transacting factors p40tax and p21x, but not that of p27rex, was enhanced about fivefold compared with that in TARS-1. The transactivating function of p40tax was intact in WLeuk-1, as evidenced by enhanced interleukin-2 receptor alpha chain expression. These results suggest that aberrant expression of HTLV-I regulatory genes and alteration of cellular genes were associated with the phenotypic progression of the WLeuk-1 cell line.

Animals↗
PubMed1992

[Pulmonary clearance of 99mTc-DTPA aerosol in patients with progressive systemic scleroderma].

Alveolar epithelial permeability was assessed in 32 patients with progressive systemic scleroderma (PSS), using 99mTc-DTPA aerosol. Immediately after the inhalation of 99mTc-DTPA aerosol for 3 to 6 minutes under normal tidal breathing, lung was imaged sequentially for 30 minutes from the posterior by a gamma camera and exponential fitting was processed on the time activity curve. T1/2 (min) was used as a parameter for the evaluation of permeability of alveolar epithelium. Patients with collagen disease showed shorter T1/2 (T1/2 = 43.7 +/- 23.8 min) than the normal volunteers (T1/2 = 76.8 +/- 8.7 min). No significant difference was observed between patients with or without interstitial changes on the chest CT. Significant correlation was not observed between T1/2 and %VC or %DLco. In 8 cases, studies were repeated in the interval of 3 to 19 months. Improvement of T1/2 was seen in 4 cases, independent of CT findings. These results suggest that 99mTc-DTPA aerosol clearance study provides information independent from other lung examinations, and may be useful for the assessment of lung interstitial changes in patients with PSS.

Administration, Inhalation↗
PubMed1992

[Clinical evaluation of 99mTc ethyl cysteinate dimer SPECT in patients with spinocerebellar degeneration; comparison with cerebral blood flow determined by PET].

Technetium-99m ethyl cysteinate dimer (99mTc-ECD) is regarded as a promising radiopharmaceutical for imaging regional cerebral blood flow (rCBF). We evaluated 99mTc-ECD SPECT comparing with rCBF images obtained by PET in 12 patients with spinocerebellar degeneration (SCD). SPECT images of 99mTc-ECD demonstrated characteristic findings of decreased rCBF in bilateral cerebellar hemisphere and almost identical with PET rCBF images in all patients based on the visual inspection. Semiquantitative analysis by drawing 14 intracranial regions of interest on SPECT and PET images revealed linear correlation between 99mTc-ECD count and rCBF measured by PET even in relatively high rCBF regions. In summary, 99mTc-ECD is a promising tracer for evaluating rCBF in patients with SCD and distribution of it correlates well with rCBF measured by PET.

Adult↗
PubMed1991

Mechanisms of molecular recognition of tRNAs by aminoacyl-tRNA synthetases.

Interactions of Escherichia coli isoleucyl- and glutamyl-tRNA synthetases and their cognate tRNAs were analyzed by phosphate-alkylation mapping with N-nitroso-N-ethylurea and/or by 1H-NMR analysis. When E. coli tRNA(Ile) was bound with isoleucyl-tRNA synthetase, many of the phosphate groups in the anticodon loop and stem and in the D-stem were protected from alkylation. This result is consistent with that of analysis of imino proton resonances due to the secondary and tertiary base pairs. These analyses also suggested that the L-shaped tertiary structure of tRNA(Ile) is distorted upon complex formation with IleRS because of disruption of some tertiary base pairs. In the case of E. coli tRNA(Glu), several phosphate groups in the D-stem and the variable loop were significantly protected by the cognate synthetase. These results indicate that the two tRNAs, unlike other tRNAs studied so far, have some of the "identity determinants" in the D-stem and/or in the anticodon stem.

Alkylation↗
PubMed1991

[Evaluation of 201Tl SPECT in patients with glioma: a comparative study with histological diagnosis, clinical feature and proliferative activity].

The purpose of this study is to clarify the usefulness of 201Tl brain SPECT in the prediction of clinical degree of malignancy. Quantitative evaluation of 201Tl uptake in the tumor was expressed as count ratio of tumor site over contralateral normal region (D/C ratio) on 201Tl SPECT image. Fourteen patients with gliomas received an intravenous administration of bromodeoxyuridine (BUdR) at surgery to label tumor cells in the DNA synthesis phase. BUdR-positive cells in excised tumor specimen were stained with anti-BUdR monoclonal antibody by indirect immunoperoxidase staining. Percentage of labeled cells in relation to the total number of tumor cells in microscopic fields was defined as labeling index (BUdR-LI). D/C ratio in patients with grade IV glioma (198.7 +/- 31.7) was higher than that in patients with grade III glioma (138.3 +/- 33.9) or more low-grade gliomas (94.2 +/- 11.9, p less than 0.001). BUdR-LI in patients with high-grade glioma was also higher than that in patients with low-grade glioma. D/C ratio correlated well (r = 0.753) with BUdR-LI, which is considered to represent proliferative activity of the tumor. D/C ratio does not only correlate well with histological grade of glioma, but with clinical course or prognosis of individual patient with glioma. In conclusion, degree of 201Tl uptake in the tumor may provide non-invasive prediction of malignancy grade of gliomas and accurate estimation of efficacy of the therapy and early detection of recurrence or malignant transformation of the tumors, by delineating viable tumor tissue in patients with gliomas.

Adult↗
PubMed1991

[Clinical study of intramuscular imipenem/cilastatin sodium in the field of obstetrics and gynecology].

The efficacy and the safety of intramuscular imipenem/cilastatin sodium (IPM/CS) were evaluated in 22 patients with obstetric and gynecologic infections. 0.5 g/0.5 g of IPM/CS was suspended in a lidocaine solution and administered in the gluteal muscle twice a day for 3-7 days. Nineteen patients with intrauterine infections were evaluable for the clinical efficacy and 22 for the safety. 1. Clinical efficacies were excellent in 6 patients, good in 11 and poor in 2, and the efficacy rate was 89.5%. Thirteen out of 14 patients who had not responded to treatments with other previously administered antibiotics showed excellent or good responses to IPM/CS. 2. Causative bacteria were eradicated in 5 patients, decreased in 2, unchanged in 3 and replaced in 3, with an eradication rate of 61.5%. 3. Among 22 patients treated with IPM/CS, an eruption and general itching were observed in 1 patient, but no abnormal laboratory test values were observed.

Adult↗
PubMed1991

[Isolation of human immunodeficiency virus type 1 (HIV-1) from seropositive hemophiliac Japanese].

We reported some biological properties of HIV-1 isolated from 16 hemophiliac Japanese and accidentally infected one mother. Peripheral mononuclear cells (PMCs) were obtained from them, one with AIDS, one with lymphadenopathy and the others were asymptomatic carriers. CD 8 depleted PMCs were obtained by panning methods. They were cocultivated with PHA-stimulated PMCs from seronegative donors. Fifteen HIV-1 isolates were obtained from 17 cases. Recovery rate was 87.5%. The replication rate of HIV-1 from AIDS patient was faster than other isolates from asymptomatic carriers. They did not from plaques on MT 4 cells. The host range study showed that all fifteen isolates infected primary macrophages and only two simultaneously infected human T cell line (MT 2). None of them showed infectivity to other T cell, B cell or monocytic cell lines. Although our study population was rather small, these results suggested that the majority of seropositive hemophiliac Japanese were already infected by HIV-1 and had the risk for the development of AIDS. Moreover, we recognized that HIV-1 from hemophiliac Japanese showed characteristic biological features, i,e, such as 1) weak cytopathic effects, 2) narrow host range and 3) tropism to primary macrophages. It is suggested that they may belong to a unique subtype of HIV-1 and their selective infectivity to primary macrophages have some relation to the clinical status of seropositive hemophiliacs. Further study is necessary to clarify these points.

Adolescent↗
PubMed1990

[Clinical evaluation of lung scintigraphy with 99mTc-technegas].

The aim of this study is to evaluate the safety and clinical usefulness of lung scintigraphy using 99mTc-technegas produced by the evaporation of pertechnetate elution at 2500 degrees C. Lung images were recorded by the gamma camera-computer system after a few deep inspirations of 99mTc-technegas. One healthy volunteer and 32 patients including 10 with lung cancer, 8 with chronic obstructive lung disease, 5 with pulmonary embolism, 2 with interstitial pneumonia, 2 with bronchiectasis and 12 with other various disease were studied. Delayed images were taken at more than 1 hour later in one healthy and 13 patients to investigate the interval changes of the intrapulmonary distribution of 99mTc-technegas. Obvious differences of radioactive distribution between early and delayed image were observed in only 2/14 cases. Penetration index (P.I.) averaged 0.81 +/- 0.11 for early images and 0.85 +/- 0.12 for delayed image. There was no significant difference between P.I. for early and delayed images. More than 97 MBq of 99mTc-macroaggregated albumin (99mTc-MAA) were required to obtain the adequate perfusion images after the acquisition of lung images with about 37 MBq of 99mTc-technegas. Bronchial deposits of 99mTc-technegas were shown in 12/33 cases and pathological defects in 26/32 patients (81.3%). Twenty three of 33 cases also had a perfusion scintigraphy with 99mTc-MAA. Ventilation perfusion mismatches were presented in 5/5 patients with pulmonary embolism and 1/10 patients with lung cancer. The safety was confirmed in all cases and clinical usefulness in 30/32 patients (94%). In conclusion, the safety and clinical usefulness of lung scintigraphy with 99mTc-technegas were proven in this study.

Adolescent↗