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T Saida

Publications and source records attributed to T Saida.

At least 91 records · Page 5Linked to original sources
PubMed1995

[Immunotherapy of multiple sclerosis: the use of magnetic resonance imaging in the evaluation of clinical trials].

Magnetic resonance imaging (MRI) is being used increasingly as a measure of outcome in monitoring the efficacy of treatment for multiple sclerosis (MS). A major advantage of MRI is that it easily detects subclinical disease activity and thus serial MRI provides an objective and sensitive tool. In the treatment of acute attacks, corticosteroids are widely used to speed recovery from disability. Recently, methylprednisolone administered in megadose pulses was reported to reduce the conversion rate of patients with optic neuritis to MS. The beneficial effect of treatment was most apparent in patients with abnormal MRI scans. Among the immunosuppressive or immunomodulatory drugs that have been used to prevent progression or reduce relapses, interferon beta 1b is the first medication confirmed to reduce accumulations of MRI detected lesions. In a cyclosporin treatment trial, MRI studies failed to show a significant benefit. Other therapies that require further definitive study include intravenous cyclophosphamide and oral methotrexate or azathioprine. A multicenter double-blind clinical trial with mizoribine is in progress in Japan and the results will be known some time during the first half of 1997.

Anti-Inflammatory Agents↗
PubMed1994

Immunoelectron microscopic localization of fibronectin in cultured human keratinocytes.

We investigated the ultrastructural localization of fibronectin (FN) in cultured human keratinocytes using an improved method of peroxidase-immunoelectron microscopy. This method enabled us to visualize the precise localization of FN within the cells while preserving the morphology. FN was localized in the protein synthetic and secretory organelles, including the rough-surfaced endoplasmic reticulum, Golgi complex, multivesicular bodies and perinuclear space. It was also detected in the extracellular space, on small regions of the villous projections of cell membranes at the site of secretion and at cell-substratum contact sites. These findings confirm that human keratinocytes synthesize, secrete and deposit FN in the pericellular matrix.

Cells, Cultured↗
PubMed1994

Primary cutaneous plasmacytosis: report of three cases and review of the literature.

BACKGROUND: Cutaneous plasmacytosis is a rare disease characterized by peculiar multiple eruptions and hypergammaglobulinemia. More than 40 cases have been reported, mainly in Japan, although information concerning the disorder was limited to individual case reports. OBJECTIVE AND METHODS: To clarify the clinicopathological and laboratory features, we reviewed 41 cases. RESULTS: All patients were Japanese and the male-to-female ratio was 1:0.6. The onset ages ranged from 20 to 62 years, with a mean and median of 37 and 37 years. A superficial lymphadenopathy was detected in 58% (22/38), and polyclonal hypergammaglobulinemia was found in 93% (38/41). No cases were associated with any apparent underlying diseases. The course was chronic without spontaneous remission. Four patients died, 3 of whom succumbed to leukemia, respiratory failure or renal failure, respectively. CONCLUSION: The results suggest that the condition appears to be a variant of reactive plasmacytic disorders of unknown origin.

Adult↗
PubMed1994

Failure to transfer multiple sclerosis into severe combined immunodeficiency mice by mononuclear cells from CSF of patients.

To confirm the reported transfer of multiple sclerosis (MS) by CSF cells, we injected CSF cells from six MS patients in the exacerbation stage into the cisterna magna of 18 severe combined immunodeficiency mice. No clinical neurologic abnormalities or light- or electron-microscopic pathologic changes were present in any transferred mice, and the reported results could not be reproduced.

Adult↗
PubMed1994

Growth dynamics of acquired melanocytic nevi. Higher reactivity of proliferating cell nuclear antigen in junctional and compound nevi than intradermal nevi.

BACKGROUND: The histogenesis of acquired melanocytic nevi is still a matter of debate. OBJECTIVE: To provide data on the histogenesis, we investigated the lesional area of acquired melanocytic nevi and the proliferative activity of the nevus cells. METHODS: Proliferative activity was examined with a monoclonal antibody against proliferating cell nuclear antigen (PCNA). The lesional area of the nevus was estimated in histologic sections. RESULTS: Intradermal nevus was the largest of the acquired melanocytic nevi but had few PCNA-positive nevus cells. In contrast, junctional nevi were smallest and showed the highest PCNA positivity. Statistical analysis showed a significant inverse correlation between the largest lesional area and PCNA positivity. CONCLUSION: The findings of the present study are in accordance with an epidermal melanocytic origin of acquired melanocytic nevi.

Antigens, Neoplasm↗
PubMed1993

FK506 and cyclosporin a regulate proliferation and proto-oncogene expression in HTLV-1-associated myelopathy/tropical-spastic-paraparesis-derived T cells.

Human T-cell-leukemia-virus-type-1 (HTLV-1) infection is associated with adult T-cell leukemia/lymphoma (ATL) and HTLV-1-associated myelopathy (HAM)/tropical spastic paraparesis (TSP). The T-cell-targeting immunosuppressants, FK506 and cyclosporin A (CsA), suppressed proliferation of the HAM/TSP-derived T-cell lines, H89-59, H89-79 and H109. FK506 and CsA also reduced expression of the proto-oncogenes, c-myc and c-fos, but not c-jun and interleukin-2-receptor-alpha (IL-2R alpha) gene in H109 cells. The growth-inhibitory effects of FK506 and CsA were not abrogated by interleukin 2 (IL-2). These results suggest that the inhibitory effects of FK506 and CsA are independent of IL-2, and are associated with the reduction of c-myc and c-fos gene expression.

Cell Division↗
PubMed1993

Campylobacter jejuni strains from patients with Guillain-Barré syndrome belong mostly to Penner serogroup 19 and contain beta-N-acetylglucosamine residues.

Campylobacter jejuni was isolated from stool cultures from 14 (30%) of 46 patients with Guillain-Barré syndrome and from 6 (1.2%) of 503 healthy persons, and the difference was highly significant (p < 0.0001). In addition, serological evidence of recent C. jejuni infection was found in 5 of 29 patients with negative stool cultures. Therefore, 41% of patients were associated with C. jejuni infection. Ten of 12 (83%) isolates from patients with Guillain-Barré syndrome belonged to Penner serogroup 19, which is a rare serogroup in sporadic patients with C. jejuni enteritis. In the lectin typing study, all serogroup 19 strains from patients with Guillain-Barré syndrome were shown to contain terminal beta-N-acetylglucosamine residues on their cell surface, but serogroup 19 strains from patients with enteritis were not.

Acetylglucosamine↗
PubMed1993

Detection of early lesions of "ungual" malignant melanoma.

BACKGROUND: The nail area is commonly affected by malignant melanoma. The prognosis of malignant melanoma of the nail is poor, because at the time of diagnosis most lesions are in the advanced stage. Correct diagnosis of early lesions could improve the prognosis. METHODS: For 3 years, all patients with nail pigmentation at the dermatology clinic were screened for five specific criteria for the diagnosis of early lesions of malignant melanoma. Histologic examination was performed on 10 of 29 lesions. RESULTS: Five of the 29 lesions were advanced malignant melanoma, easily diagnosed clinically. Two of the remaining 24 lesions fulfilled most of our clinical criteria of early malignant melanoma of the nail apparatus; that is, they appeared as melanonychia striata during adulthood, were wide in breadth measuring 9 and 11 mm, and showed variegated shades of brown. Periungual pigmented macule (Hutchinson's sign) was observed in one of the two cases. Total resection of the lesions was performed, followed by skin grafting. CONCLUSIONS: Histologically, an increased number of atypical melanocytes, mainly arranged as solitary units, were observed only in the epithelia of the nail matrix and of the nail-bed, confirming that these lesions were "ungual" malignant melanoma in situ. Such an early lesion of malignant melanoma of the nail apparatus can be completely cured with conservative excision, and the phalanx of the affected digit can be preserved.

Adolescent↗
PubMed1993

Effective detection of plantar malignant melanoma.

BACKGROUND: As the sole of the foot is the most prevalent site of malignant melanoma in non-Caucasians, early detection of the neoplasm at this anatomical site is very important. In our previous study, we proposed a clinical guideline that acquired melanocytic lesions on the sole larger than 7 mm in maximum diameter should be examined histologically. METHODS: Eighty-one Japanese patients with the complaint of plantar pigmented lesions were screened at our dermatology clinic during 3 years using the 7-mm criterion. RESULTS: Of the total 80 melanocytic lesions on the sole, 14 lesions were larger than 7 mm in maximum diameter, excluding congenital lesions. Diagnoses of the 14 "large" lesions were as follows: advanced malignant melanoma, 8 lesions; early malignant melanoma (malignant melanoma in situ), 1 lesion; acquired melanocytic nevus, 4 lesions, and volar melanotic macule, 1 lesion. CONCLUSIONS: The present study confirmed the validity of the 7-mm criterion for the early effective detection of plantar malignant melanoma.

Adolescent↗
PubMed1993

Lethal posttransfusion graft-versus-host disease. Report of four cases.

Four cases of posttransfusion graft-versus-host disease are reported. Three were caused by high-dose transfusion of non-irradiated fresh blood during open-heart surgery and 1 by the contaminated lymphocytes in packed red blood cells transfused for renal injury. In 1 patient, change of HLA type of peripheral lymphocytes was demonstrated.

Aged↗
PubMed1992

Proliferative activity of cutaneous melanocytic neoplasms defined by a proliferating cell nuclear antigen labelling index.

To evaluate the proliferative activity of benign, borderline and malignant cutaneous melanocytic neoplasms, 30 cases of malignant melanoma (MM) and 41 cases of naevi were studied by immunostaining using a monoclonal antibody against proliferating cell nuclear antigen (PCNA). PCNA is a nuclear antigen expressed in the late G1 and S phase and serves as a marker of proliferating cells. Invasive MM and MM in situ showed much higher PCNA positivity rates than melanocytic naevi (invasive MM, 18.0%; MM in situ, 11.3%; ordinary melanocytic naevi, 2.6%). The PCNA positivity rate did not increase significantly with the thickness of MM. Among ordinary melanocytic naevi, junctional naevi had a higher PCNA positivity rate than compound or intradermal naevi. Mean PCNA positivity rates for Spitz's naevi and sporadic dysplastic naevi were within the range for ordinary melanocytic naevi, indicating the benign nature of both types of naevus. Contrary to some previous studies, MM in situ showed high proliferative activity, indicating that cells of MM in situ are actively proliferating. This study clearly demonstrates that MM and various types of naevi can be separated according to differences in proliferative activity defined by the PCNA labeling index.

Antibodies, Monoclonal↗
PubMed1992

Distribution patterns and frequency of proliferating cells in cutaneous keratinocytic neoplasms. Immunohistochemical study with a monoclonal antibody (TOB7) used against proliferating cell nuclear antigen.

BACKGROUND: Almost all markers for proliferating cells need freshly frozen tissues for evaluation; therefore retrospective study is impossible. OBJECTIVE: In the present study, a murine monoclonal antibody (TOB7) against the proliferating cell nuclear antigen (PCNA) was used for the analysis of cell kinetics of cutaneous keratinocytic neoplasms. The antibody is applicable to formalin-fixed, paraffin-embedded tissues. METHODS: The frequency of PCNA-positive cells and their distribution patterns were immunohistochemically investigated in various cutaneous keratinocytic neoplasms. RESULTS: Squamous cell carcinoma and Bowen's disease showed significantly increased numbers of PCNA-positive cells when compared with other keratinocytic neoplasms. A characteristic marginal or random distribution pattern of PCNA-positive cells was observed in the lesions of each disease category. CONCLUSION: Important information on the growth dynamics of keratinocytic neoplasms was obtained in this retrospective immunohistochemical study.

Antibodies, Monoclonal↗
PubMed1992

HLAs and genes in Japanese patients with multiple sclerosis: evidence for increased frequencies of HLA-Cw3, HLA-DR2, and HLA-DQB1*0602.

The distribution of HLA-A, B, C, DR and DRB1, DQB1, DPB1 alleles was studied in 60 Japanese patients with clinically definite multiple sclerosis (MS) using serologic and genomic analysis. We found significant associations with HLA-Cw3 (p = 0.002, pc = 0.012, RR = 3.2), DR2 (p = 0.007, RR = 2.6), and DQB1*0602 (p = 0.04, RR = 4.0) in Japanese patients for the first time. The combined presence of Cw3 and DR2 gave a higher risk than each antigen alone. The reported increase in the frequency of DPw4 in Japanese MS patients [12] could not be confirmed by our genomic study. The frequencies of all of the residues in each variable region of the amino acid sequences of DQ beta and DP beta chains were not different between the MS patients and the controls. These results suggest that MS susceptibility may result from polygenic influences and from the presence of environmental factors.

Alleles↗
PubMed1992

Immunohistochemical studies of blood group antigens ABH in cutaneous angiosarcoma.

Eight angiosarcomas were clinicopathologically and immunohistochemically investigated. Four of the angiosarcomas originated in the scalp of the elderly, and four cases were angiosarcomas associated with chronic lymphedema after hysterectomy for uterine carcinoma or after mastectomy for breast carcinoma. Six of the angiosarcomas showed conventional histopathology, whereas the remaining two cases were considered cutaneous epithelioid angiosarcoma. Immunohistochemical studies for blood group antigens ABH were carried out. Three of the conventional angiosarcomas were weakly positive and three were moderately positive with antigens ABH. The antigens were strongly positive in the two epithelioid angiosarcomas. The biologic course of the two epithelioid angiosarcomas was longer than that of the other six cases. This study suggested that the strong positivity of blood group antigens may be one of the characteristics of epithelioid angiosarcoma.

ABO Blood-Group System↗
PubMed1992

Analysis of the expression of Hanganutziu-Deicher (HD) antigen in human malignant melanoma.

Hanganutziu-Deicher (HD) antigen is classified as a heterophile antigen and chemically defined as a ganglioside and/or glycoprotein containing N-glycolylneuraminic acid (NeuGc). HD antigen is absent from normal tissues in humans and chickens but can be expressed in human malignant neoplasms including melanoma. We analysed HD antigen expression in ganglioside and glycoprotein fractions of human melanoma tissues by means of TLC enzyme-immunostaining and Western blotting with biotinylated affinity-purified chicken anti-NeuGc-lactosylceramide (anti-HD3) antibody. No HD-antigenic gangliosides were detected in 11 specimens of human melanoma. In the glycoprotein fractions, however, a strong HD-positive band of 58 kD was detected in 3 of 10 specimens and several minor bands (37 kD, 13.5 kD, etc.) were also found in 5 specimens. The positive bands completely disappeared after treatment with neuraminidase. These results suggest that HD antigen is expressed on the carbohydrate chains of glycoproteins but not on those of gangliosides in human melanoma.

Antigens, Heterophile↗
PubMed1992

[Analysis of surface membrane antigens, cytoskeletal proteins and N-myc oncogene in pediatric solid malignant tumors, their diagnostic usefulness and relevant problems].

Neuroblastoma (NB), primitive neuroectodermal tumor (PNET), Ewing's sarcoma and rhabdomyosarcoma (RMS) are solid malignant tumors in childhood. Microscopically these tumors are grouped as small-round-cell tumors, and a different diagnosis is sometimes difficult. Cell surface membrane antigen, cytoskeletal protein and N-myc amplification and over-expression were analyzed in these cell lines and tumor tissues for the accurate diagnosis. NB and PNET could be distinguished from Ewing's sarcoma and RMS by the panel of monoclonal antibodies against cell surface membrane antigens. The cytoskeletal protein analysis is useful for the diagnosis of RMS and leiomyosarcoma. Alpha-smooth muscle actin and/or desmin were demonstrated in the S-type (epithelial-like) cells in 3 NB cell lines, suggesting the differentiation pathway of NB into smooth muscle cells. N-myc amplification and over-expression were observed in NB cell lines as well as one RMS cell line. The occurrence of N-myc amplification and over-expression in the RMS cell line cautions us against using N-myc as a distinguishable marker for NB.

Adolescent↗