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T Nagatani

Publications and source records attributed to T Nagatani.

At least 55 records · Page 3Linked to original sources
PubMed1995

Ultrahigh-resolution low-voltage SEM reveals ultrastructure of the glucan network formation from fission yeast protoplast.

The refined field emission SEM, S-900 LV which gives better resolution especially at low voltages below 5 kV was developed for ultrahigh resolution scanning electron microscopy. A visualization test at x 300,000 was made using a gold-evaporated magnetic tape, and the resolution was found to be about 1 nm at 2.5 kV. The ultrastructure of the cell wall, especially the reverting glucan network, from the protoplast of Schizosaccharomyces pombe was studied using this improved ultrahigh-resolution low-voltage SEM (UHR-LVSEM). The results with uncoated reverting protoplasts observed with this microscope revealed that the network was originally formed as secreted particles scattered on the protoplast surface and these were subsequently stretched to microfibrils about 2 nm thick. The microfibrils were twisted around each other and joined together so that they developed into 8-nm-thick fibrils, forming a ribbon-shaped network of glucans about 16-nm-thick which covered the entire protoplast surface. The UHR-LVSEM images of reverting protoplasts treated with glucanase confirmed that the particles scattered on the protoplast surface in the initial stage of regeneration were glucan in nature.

Animals↗
PubMed1994

Buspirone enhances head twitch behavior in mice.

We studied the effects of buspirone, a 5-HT1A receptor agonist, on head twitch behavior induced by 5-hydroxy-L-tryptophan (5-HTP) administered together with pargyline in mice. Buspirone dose dependently (0.1-10 mg/kg i.p.) enhanced head twitch behavior. This effect was blocked by (-)-propranolol and NAN-190 (1-(2-methoxyphenyl)-4-[4-(2-phthalimido)butyl]-piperazine hydrobromide). The enhancing effect of buspirone was also observed when mice were pretreated with p-chlorophenylalanine. These findings suggest that the enhancing effect of buspirone on head twitch behavior may be exerted through the activation of post-synaptic 5-HT1A receptors.

5-Hydroxytryptophan↗
PubMed1994

Cerebellar stroke due to vertebral artery occlusion after cervical spine trauma. Two case reports.

The authors report two cases of cerebellar infarction due to vertebral artery (VA) occlusion resulting from cervical spine trauma. In one patient with dens and C2 body fracture, the left VA was occluded, resulting in a left cerebellar infarction. The second patient, with a subluxation of C4 on C5, presented with cerebellar swelling and infarction along with acute hydrocephalus secondary to bilateral vertebral artery occlusion. Because vertebral artery injuries with cervical trauma are rarely symptomatic, they can be easily overlooked. Bilateral or dominant vertebral artery occlusion, however, may cause rapid and fatal ischemic damage to the cerebellum and brain stem. Rapid recognition and optimal treatment for this injury depends on early vertebral artery angiography.

Angiography↗
PubMed1994

Comparative study of cutaneous T-cell lymphoma and adult T-cell leukemia/lymphoma.

An important disease entity distinct from cutaneous T-cell lymphoma (CTCL) in Japan is adult T-cell leukemia/lymphoma (ATL), which shows almost the same phenotype as CTCL, ie, a helper/inducer T-cell phenotype (CD4-positive, CD8-negative), and usually involves the skin. This article describes differences between CTCL and ATL in terms of clinical and immunopathologic cell surface features. In patients with ATL, the predominant physical findings were lymph node, bone marrow and skin involvement, hepatosplenomegaly, leukemic manifestations, and an aggressive course. In patients with CTCL, in contrast, only skin lesions predominated at the onset of the disease and a relatively good prognosis was shown. The predominant phenotype of the neoplastic cells in the skin of patients with CTCL was CD3+, CD4+, CD29+, CD45RO+, HLA-DR+, HLA-DQ+, CD7-, L-selectin-, and CD45RA-. Some phenotypic discrepancy was found between the neoplastic cells in the peripheral blood, lymph nodes and skin of patients with ATL with respect to CD45RA and CD45RO, and CD7, CD29, CD25, and HLA-DR. That is, the predominant neoplastic cell phenotype was helper T-cell, which was CD3+, CD4+, L-selectin+, CD25+, CD45RA+, HLA-DR+, CD29-, and CD45RO- in peripheral blood, and CD3+, CD4+, L-selectin+, CD29+, CD45RO+, HLA-DR+, and CD45RA- in the skin and lymph nodes. Phenotypic heterogeneity of ATL cells and heterogeneity of CD45R isoform expression on ATL cells were evident in different organs. These findings confirm that the difference in antigen expression on the cell surface might reflect the clinical features of ATL and CTCL. CTCL cells do not share the same phenotype as ATL cells.

Adult↗
PubMed1993

(R)-1,2,3,4-tetrahydro[1]benzothieno[2,3-c]pyridines: novel optically active compounds with strong 5-HT1A receptor binding ability exhibiting anticonflict activity and lessening of memory impairment.

(R)-1,2,3,4-Tetrahydro[1]benzothieno[2,3-c]pyridine derivatives (60-114) were synthesized. The (R)-isomers have affinity for the 5-HT1A receptor while the (S)-isomers have no such ability. The affinity of the (R)-isomers was discussed on the basis of structure-activity relationships between the affinity and hydrophobicity of the (R)-isomers. Compounds 71 and 107, which are representative derivative compounds, have anticonflict activity and lessening of memory impairment. In particular, compound 107 cannot bind to receptors other than the 5-HT1A receptor, demonstrating that it is a unique compound with a different mechanism of action from that of conventional anxiolytics.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed1993

Role of 5-HT1A receptors in the forced swimming wheel test in reserpine-treated mice.

The antidepressant-like effect of 8-hydroxy-2-(di-n-propylamino)tetralin(8-OH-DPAT), a selective 5-HT1A receptor agonist, was studied in the forced swimming wheel test in reserpine-treated mice. 8-OH-DPAT and the antidepressant imipramine, dose-dependently increased the number of turns of a water wheel made by mice. This effect of imipramine (30 mg/kg, i.p.) was enhanced by reserpine treatment 24 hr before the test. The effect of 8-OH-DPAT (0.3 mg/kg, i.p.) was also enhanced in reserpine-treated mice. This enhanced effect of 8-OH-DPAT was blocked by pretreatment with the 5-HT1A receptor antagonists, (-)-propranolol (3 mg/kg, i.p.) and NAN-190 (1 mg/kg, i.p.), but was not blocked by a beta-blocker, (-)-atenolol (3 mg/kg, i.p.). 8-OH-DPAT did not affect locomotor activity in the reserpinized mice and did not affect the reduction of monoamine content induced by reserpine. These results suggest that the effect of 8-OH-DPAT in increasing the number of turns of the wheel made by mice was exerted through a 5-HT1A receptor and that this effect did not reflect only changes in the locomotor activity of the mice.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed1993

Successful treatment of adult T-cell leukemia/lymphoma with MACOP-B, M-FEPA and VEPP-B combination chemotherapy.

A 45-year-old man was referred to our department in March of 1989. Physical examination showed erythroderma, palmo-plantar hyperkeratosis, generalized lymphadenopathy, hepatosplenomegaly, and leukemic manifestation. The lymphocyte count in the peripheral blood before treatment was 1.7 x 10(4) cells/mm3. Atypical lymphocytes such as flower cells and lobulated cells were seen in the peripheral blood. A sample excised from a lymph node showed immunoblastic, pleomorphic T cells by a modified classification scheme of the Working Formulation. A high level of serum LDH was detected (2.1 times the upper normal limit). Anti HTLV-1 antibody was also detected in the serum. The atypical lymphocytes were positive for CD3, CD4, CD5, CD7 and HLA-DR, and negative for CD8. Thus, the clinical, pathologic and immunologic features were those of typical acute-type ATL. The patient was treated with VEPA-M for three months starting in March of 1989. Because of poor response, the patient was then treated with MACOP-B, M-FEPA, and VEPP-B for about one year from June of 1989 and has been free of disease up to the time of writing, March of 1993.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

A case of cutaneous B-cell lymphoma with a storiform stromal reaction.

A case of cutaneous B-cell lymphoma is described. The patient was treated only by surgical excision of the skin tumors five times during a period of about two years from February of 1984 to October of 1986. After the last surgical excision, a continuous disease-free period was achieved. Biopsy samples showed dense lymphocytic infiltrations with discrete masses in the dermis and subcutis; one of them showed a storiform pattern. At the time, the infiltrating cells were composed of medium and large lymphoid cells and spindle-shaped cells. The medium and large lymphoid cells were positive for CD20, CD22 and HLA-DR and negative for CD3, CD4, CD5, CD8, CD43, and kappa and lambda light chain. The spindle-shaped cells were negative for CD20, CD43, kappa and lambda light chain, lysozyme, and S-100 protein.

Adult↗
PubMed1993

A case of cutaneous B-cell lymphoma treated successfully with MACOP-B.

A case of cutaneous B-cell lymphoma successfully treated by MACOP-B therapy is described. The patient was a 43-year-old man with reddish tumors measuring 3 to 7 cm in diameter on the right cheek and the post-auricles. Histopathologically, massive infiltrations of medium-sized atypical lymphoid cells were found in the reticular dermis and subcutis. A clear zone beneath the epidermis was also detected. The atypical lymphoid cells were positive for CD19, CD20, CD22 and HLA-DR but negative for CD3, CD4, CD5, CD10, CD43, CD45RO and CDw75. The patient was treated successfully with the MACOP-B protocol from March of 1990 to May of 1990. Since April of 1990, he has been free of disease.

Adult↗
PubMed1993

Cutaneous B-cell lymphoma--a clinical, pathological and immunohistochemical study.

Eleven cases of cutaneous B-cell lymphoma (CBCL) were studied. The ages at presentation ranged from 34 to 79 years (mean = 59.9 years). Six patients were female and five male. Five of the 11 patients had a solitary tumour and the other six had multiple tumours at initial presentation. According to Burg's classification, six cases were at stage I, two stage II, two stage III and one was at stage IV at initial presentation. Abnormalities in laboratory data were rare, except for serum lactic dehydrogenase values. Epidermotropism was not detected, and the area mainly affected by neoplastic cells was the reticular dermis (seven cases) and subcutis (four cases). Biopsy specimens from the patients analysed by immunohistochemical techniques on paraffin or cryostat sections showed CD20 and/or CD22 positivity. Biopsy specimens from two patients which showed CD10 positivity were diffuse large cell types by the working formulation and presented as pre-B-cell lymphoma. At least two groups of CBCL were demonstrable on the basis of prognosis. One was a benign low-grade lymphoma presenting with solitary tumours, mature B-cell markers and intermediate-grade pathology, and the other was a high-grade lymphoma with multiple tumours, pre-B-cell or mature B-cell markers and a poor prognosis.

Adult↗
PubMed1993

A polymerase chain reaction system for rapid diagnosis of scrub typhus within six hours.

A rapid diagnostic system for scrub typhus (tsutsugamushi disease) was established using the polymerase chain reaction (PCR) combined with microplate hybridization. With this system, diagnosis can be made within six hours without the need for radioisotopes, electrophoresis, or membrane hybridization. The use of a PCR processor and DNA-precoated enzyme-linked immunosorbent assay plates allows a rapid and precise diagnosis to be easily made even in primary medical care clinics.

Aged↗
PubMed1993

[Lymphomas of the skin].

Malignant lymphoma of the skin is a type of extranodal lymphoma, in which the main organ involved is the skin, and 80-90% of cases in Japan show a T-cell phenotype. Mycosis fungoides (MF) and Sézary syndrome (SS) are common T-cell lymphomas of the skin with a benign prognosis. Therefore, various forms of topical therapy, such as topical steroid, photochemotherapy (PUVA) and interferons, have been indicated for the low-risk group (stages I A, I B and II A), whereas electron-beam irradiation, retinoid plus interferon (IFN), photopheresis and deoxycoformycin (DCF) plus IFN have been indicated for intermediate-risk group (stages II B and III). The cutaneous involvement of B-cell lymphoma has been considered an unmistakable sign of progression and dissemination of lymphoid disease, and is thus associated with a poor prognosis. However, some primary cutaneous B-cell lymphomas (CBCLs) show a benign prognosis, and electron-beam irradiation has been indicated for early-stage CBCL (stages I and II). However, the prognosis of high-risk group CTCL (stage IV) and cutaneous B-cell lymphoma (CBCL) (stages III and IV) is poor. Therefore, an effective multiagent combination chemotherapy, such as MACOP-B, M-BACOD or ProMACE-Cyta BOM is required for patients with advanced-stage CTCL and CBCL. With regard to age at the time of the first medical examination, patients with CTCL or CBCL at an advanced stage have a tendency to be older. Therefore, a mild but effective therapy, such as DCF plus IFN is recommendable.

Antineoplastic Combined Chemotherapy Protocols↗