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T Saida

Publications and source records attributed to T Saida.

At least 55 records · Page 3Linked to original sources

HLA-DRB1 and tumor necrosis factor gene polymorphisms in Japanese patients with multiple sclerosis.

We studied genetic polymorphisms in the tumor necrosis factor (TNF) region as well as HLA-DRB1 of 42 patients with Western-type multiple sclerosis (MS) and 38 with Asian-type MS in Japan. The sex ratio (Female:Male) was significantly higher in Asian than in Western type MS (3.8 vs. 1.3, P = 0.038). The frequency of HLA-DRB1 * 1501 allele in the Western-type MS group increased significantly compared with the control group, while Asian-type MS and control groups showed similar distribution in the frequencies of HLA-DRB1 alleles. No significant differences existed in the TNF region, however, including TNF-a microsatellite alleles. The results suggest that MS in Asians may present two different clinical and immunogenetic manifestations.

Adult↗

Characteristic epiluminescent microscopic features of early malignant melanoma on glabrous skin. A videomicroscopic analysis.

OBJECTIVE: To investigate the characteristic epiluminescent microscopic features of early lesions of malignant melanoma affecting glabrous skin, which is the most prevalent site of the neoplasm in nonwhite populations. DESIGN: The epiluminescent microscopic features of various kinds of melanocytic lesions affecting glabrous skin were investigated using a videomicroscope. All the diagnoses were determined clinically and histopathologically using the standard criteria. SETTING: A dermatology clinic at a university hospital. PATIENTS: The following 130 melanocytic lesions consecutively diagnosed at our department were examined: 16 lesions of acral lentiginous melanoma, 6 lesions of malignant melanoma in situ, and 108 lesions of benign melanocytic nevus (acquired or congenital). MAIN OUTCOME MEASURE: The incidence of each characteristic epiluminescent feature was compared among disease categories. RESULTS: On epiluminescent microscopy, malignant melanoma in situ and the macular portions of invasive malignant melanoma showed accentuated pigmentation on the ridges of the skin markings, which are arranged in parallel patterns on glabrous skin. This "parallel ridge pattern" was found in 5 (83%) of 6 lesions of malignant melanoma in situ and in 15 (94%) of 16 lesions of malignant melanoma. The parallel ridge pattern was rarely found in the lesions of benign melanocytic nevus. Most benign melanocytic nevi showed 1 of the following 3 typical epiluminescent patterns: (1) a parallel furrow pattern exhibiting pigmentation on the parallel sulci of [he skin markings (54%), (2) a latticelike pattern (21%), and (3) a fibrillar pattern showing filamentous or meshlike pigmentation (15%). The remaining 11 benign nevi (10%) showed a nontypical pattern. CONCLUSION: Because epiluminescent microscopic features of early malignant melanoma on glabrous skin are characteristic, we can effectively detect early lesions using this noninvasive method.

Adult↗

Characteristic magnetic resonance imaging findings in Machado-Joseph disease.

OBJECTIVE: To clarify the characteristic magnetic resonance imaging (MRI) findings in patients with Machado-Joseph disease (MJD) diagnosed by genetic analysis. PATIENTS AND METHODS: Using MRI, we examined 31 patients genetically diagnosed as having MJD, 20 patients with sporadic olivopontocerebellar atrophy, and 26 control subjects. RESULTS: The MRIs of patients with MJD disclosed remarkably reduced width of the superior cerebellar peduncles, atrophy in the frontal and temporal lobes, diminished transverse diameter of the globus pallidus, and decreased anteroposterior and transverse diameters of the pons, which correlated with the width of the middle cerebellar peduncle. The width of the superior cerebellar peduncles also correlated with the diameter of the dentate or red nucleus in patients with MJD, but not in controls or in patients with sporadic olivopontocerebellar atrophy. On T2- and/or proton-weighted axial MR imaging, a high signal intensity in the transverse pontine fibers was observed in 14 (45.2%) of 31 patients with MJD and in all patients with sporadic olivopontocerebellar atrophy, but not in any controls. CONCLUSION: Affected afferent and efferent cerebellar tracts and atrophy of the frontal and temporal lobes and globus pallidus are characteristics of MRI of patients with MJD.

Adult↗

Genetic contribution of the tumor necrosis factor region in Guillain-Barré syndrome.

We studied genetic polymorphisms in the tumor necrosis factor (TNF) region in 81 Japanese patients with Guillain-Barré syndrome (GBS) and 85 controls. A significantly higher frequency of the 100-base pair (bp) (TNFa2) allele of the TNFa microsatellite marker, which is associated with high TNF alpha production, existed in Campylobacter jejuni-positive (Cj+) GBS patients than in controls, suggesting the involvement of a genetic predisposition to high TNF alpha secretion in the development of C. jejuni-related GBS.

Alleles↗

Antibodies to gangliosides and galactocerebroside in patients with Guillain-Barré syndrome with preceding Campylobacter jejuni and other identified infections.

The relationship between preceding infections and antibodies to glycolipids was investigated in 205 Japanese patients with Guillain-Barré syndrome (GBS). Serological evidence of recent Campylobacter jejuni (C. jejuni) infection was found in 45% of the patients, compared with 1% in healthy controls. In contrast, recent infection of cytomegalovirus (CMV), Mycoplasma pneumoniae (M. pneumoniae) and Epstein-Barr virus (EBV) was detected in only 5%, 2% and none of the patients, respectively. C. jejuni-associated GBS was more frequent in early spring than in other seasons. All stool specimens positive for C. jejuni isolation were obtained within 10 days after the onset of GBS symptoms. Of 13 C. jejuni isolates from GBS patients, 10 (77%) belonged to Penner serotype 19 (heat-stable, HS-19). Elevated titers of anti-GM1 antibody were found in 8 (80%) of 10 GBS patients whose C. jejuni isolates belonged to HS-19 and in none of those infected with non-HS-19 C. jejuni (P = 0.04), and in 49% of 92 patients with C. jejuni infection and 25% of patients without infection of C. jejuni, CMV, EBV, or M. pneumoniae (P = 0.0007). The frequencies of elevated antibody titers to GD1a, GD1b and GQ1b were also significantly higher in GBS patients associated with C. jejuni than those not associated with C. jejuni, CMV, EBV, and M. pneumoniae. GBS in Japan seems to be associated more frequently with C. jejuni and less frequently with CMV than in Europe and North America.

Adolescent↗

Moesin and CD44 expression in cutaneous melanocytic tumours.

The ERM (ezrin, radixin and moesin) family members, located just beneath the plasma membranes, are thought to be involved in the association of action filaments with the plasma membrane. One of the family members, moesin, is reported to bind to CD44. Splice variants of CD44 are thought to be associated with tumour progression or differentiation. Our aim was to investigate immunohistochemically the expression of moesin together with CD44 on paraffin tissue sections of a series of melanocytic tumours. The material included 12 ordinary melanocytic naevi, six Spitz naevi, eight dysplastic naevi, six blue naevi, seven malignant melanomas in situ, 15 primary malignant melanomas, five metastatic melanomas to the skin and five lymph node metastases. In the normal skin and the melanocytic tumours the expression of moesin was largely similar to that of CD44 standard. Strong moesin staining was observed in benign melanocytic lesions and melanomas in situ. However, the expression was decreased in advanced malignant melanomas. The moesin labelling in melanoma cells was downregulated with the depth of dermal invasion. The immunoreactivity was also diminished in the skin metastases and the lymph node metastases of melanoma. These results suggest that in melanocytic tumours, the alternation in the expression of moesin may be involved in the progression of malignancy.

Adult↗

The 97 kDa linear IgA bullous dermatosis antigen is not expressed in a patient with generalized atrophic benign epidermolysis bullosa with a novel homozygous G258X mutation in COL17A1.

The nature and expression pattern of the 97 kDa linear IgA bullous dermatosis antigen (LAD-1) and its role in epidermolysis bullosa have not been fully elucidated. In this study, we examined the expression of LAD-1 in the skin specimens of 70 patients with the various subtypes of epidermolysis bullosa, including simplex (n = 23), junctional (n = 15), and dystrophic variants (n = 32). For immunolabeling, we used two recently developed monoclonal antibodies to LAD-1 whose epitopes were ultrastructurally localized in the lamina lucida between NC16A and carboxyterminal domains of BPAG2, as well as autoantibodies against LAD-1 from the sera of two patients with linear IgA dermatosis. Among the 70 patients, only one patient with generalized atrophic benign epidermolysis bullosa failed to demonstrate LAD-1 expression. Although other major basement membrane components, including laminin 5, BPAG1, plectin, alpha6 and beta4 integrins, as well as type IV and type VII collagens were normally expressed, BPAG2/type XVII collagen was absent from the skin of this patient. Mutation analysis on COL17A1 using polymerase chain reaction amplification, heteroduplex scanning, and direct nucleotide sequencing revealed that this patient was homozygous for a novel nonsense mutation G258X in exon 11, and her parents were heterozygous carriers for this mutation. This is the first mutation located in the intracellular domain of BPAG2, and resides 817 bp upstream from the N-terminal amino acid sequence of LAD-1. These findings indicate that the absent expression of LAD-1 is observed in a BPAG2-deficient generalized atrophic benign epidermolysis bullosa patient with mutations in both alleles of COL17A1, and not in other epidermolysis bullosa subtypes. These findings also support the notion that LAD-1 is a degradation product of BPAG2.

Antigens↗

Expression of moesin and its associated molecule CD44 in epithelial skin tumors.

Moesin, one of the ERM (ezrin; radixin; moesin) family members, is directly associated with the cytoplasmic domain of CD44, which is now thought to be related to the metastatic potential of tumor cells. Using immunohistochemistry we investigated the expression of moesin in normal epidermis and various kinds of epithelial skin tumors: squamous cell carcinoma, verrucous carcinoma, Bowen's disease, solar keratosis, keratoacanthoma, basal cell carcinoma, and extramammary Paget's disease. Normal skin showed positive epidermal staining for moesin with the exception of the stratum corneum. The expression of moesin varied with the type of skin tumor. In basal cell carcinoma, Bowen's disease, and extramammary Paget's disease, moesin expression was either faint or negative. In contrast to Bowen's disease, invasive squamous cell carcinoma showed more intense and heterogeneous staining of the cytoplasm and the cell membrane. Verrucous carcinoma was weakly positive, with a tendency for the moesin to be distributed in the cell membrane. The staining pattern of moesin varied among the different kinds of epithelial skin tumors, and its expression was generally similar to that of the standard form of CD44. These results suggest that moesin is closely inter-related with CD44 in epithelial skin cells as seen in other cellular systems, and that the variable pattern of moesin staining among the skin tumor cells could reflect expression disorders associated with the transformation.

Carcinoma↗

A case of an inflammatory variant of epidermolysis bullosa acquisita: chronic bullous dermatosis associated with nonscarring mucosal blisters and circulating IgG anti-type-VII-collagen antibody.

A 42-year-old man showed prominent blistering lesions of the mouth and esophagus in addition to a few bullous lesions of the skin. Direct immunofluorescence microscopy revealed distinct linear deposition of IgG and C3 at the epidermal basement membrane zone where slight deposition of IgA and IgM was also observed. In direct immunoelectron-microscopic examination, antibody was detected in the sublamina densa of the basement membrane zone. Immunoblot analysis with dermal extracts demonstrated that the patient's serum contained circulating IgG antibodies against the 290-kD protein, which comigrated with type VII collagen. The lesions healed without any scars. The results of these studies corresponded to the laboratory findings in epidermolysis bullosa acquisita (EBA), although the clinical features were distinct from classic EBA.

Adult↗

HLA and T-cell receptor gene polymorphisms in Guillain-Barré syndrome.

OBJECTIVE: We examined a possible involvement of genetic factors influencing the development of Guillain-Barré syndrome (GBS). METHODS: We studied T-cell receptor (TCR), alpha-chain constant (AC), and beta-chain variable (BV) gene polymorphisms using microsatellite markers and serologic HLA class I antigens, HLA-DRB1, and HLA-DQB1 alleles in 81 Japanese patients with GBS and 87 controls. RESULTS: There were no significant differences in these genetic markers between GBS patients and controls. Subgrouping of GBS patients according to recent Campylobacter jejuni infection, the presence of anti-GM1 antibody in the sera, or their combinations also failed to reveal significant associations with these genetic markers. There was, however, a tendency for an increased frequency of HLA-DRB1*0803 in the C. jejuni + GM1 + GBS group, when compared with controls. CONCLUSIONS: The data suggest that the roles of TCRAC, T-cell receptor beta-chain variable (TCRBV), HLA class I or class II in the development of GBS are not critical, and further research is necessary to clarify other genes encoded within the HLA region for genetic susceptibility to GBS.

Campylobacter Infections↗

Characterization of Campylobacter jejuni isolates from patients with Guillain-Barré syndrome.

Campylobacter jejuni is a major pathogen preceding Guillain-Barré syndrome (GBS), and most C. jejuni isolates from GBS patients belong to Penner serotype 19 (heat-stable; HS-19). We analyzed sixteen independent clinical isolates from GBS patients, twelve of which belonged to HS-19, three to HS-2, and one to HS-4, using PCR-based RFLP analysis of a flagellin-A (flaA) gene. Two isolates from patients with Miller Fisher syndrome (MFS), and 27 from patients with uncomplicated enteritis were also examined. All HS-19 isolates, regardless of GBS, showed an identical pattern (Cj-1) by RFLP typing and were distinguishable from those of the other Penner serogroups. In contrast, HS-2 and HS-4 isolates were divided into several different RFLP groups, suggesting HS-19 strains are genetically distinctive among C. jejuni isolates. A DNA fingerprinting method also failed to detect any specific band pattern for GBS-related C. jejuni isolates. We examined relationships among anti-GM1 antibody titres in the sera of GBS patients, clinical forms of GBS, serotype of C. jejuni, and the presence of GM1-like structures in lipopolysaccharide (LPS) components from C. jejuni isolates by immunoblotting. HS-19 related GBS was significantly associated with elevated anti-GM1 antibody titers in the sera of the patients, but not associated with any clinical pattern of GBS. No significant correlations were found between anti-GM1 antibody and the pattern of disease, or between GBS-related C. jejuni strains and the presence of GM1-like structures. HS-19 strains seem to be unique among C. jejuni isolates, and HS-19-related GBS may provide an excellent model for clarification of the pathogenesis of GBS.

Blotting, Western↗

CAG repeat length and disease duration in Machado-Joseph disease: a new clinical classification.

To evaluate the clinical characteristics of Machado-Joseph disease (MJD) with reference to CAG repeat length and disease duration, we analyzed neurologic findings in 108 patients from 84 families. The majority of MJD patients presented with an ataxic gait as the initial symptom. Dysarthria and nystagmus were observed from an early stage. Bulging eyes, muscle atrophy and bradykinesia developed later. Patients with a shorter CAG repeat length or later onset had more frequent involvement of proprioceptive sensory deficit. Incidence of abnormal reflexes, tones, and proprioceptive sensation was not associated with disease duration, but with CAG repeat length. Based on these results, we propose a new clinical classification: type A (juvenile type), with hyperreflexia and dystonia, but without a proprioceptive sensory deficit; type C (adult type), with hyporeflexia and a proprioceptive sensory deficit, but without dystonia; and type B (intermediate type), the remaining patients with a mixed presentation.

Adult↗

Central nervous system lesions in rats infected with Friend murine leukemia virus-related PVC441: ultrastructural and immunohistochemical studies.

Newborn F344 rats were injected intraperitoneally with PVC441 virus, a neuropathogenic variant of Friend murine leukemia virus, and developed paraparesis of hind limbs 35-40 days after infection. Immunohistochemical study using monoclonal anti-PVC441 antibody revealed that in the central nervous system endothelial cells but not neuronal or glial cells were infected with PVC441 virus. The major pathological changes were myelin vacuolation and oligodendrocyte degeneration in the white matter at the white-gray border zone. Anterior and lateral funiculi and intercalated myelin of anterior horns were dominantly affected in the spinal cord from the sacral to cervical level. The midbrain was also vacuolated. An ultrastructural study demonstrated that many viral particles were present outside the endothelial cells but only sparsely inside endothelial cells and pericytes. Endothelial cell membranes and tight junctions were also disrupted. Immunohistochemical studies with antibodies against major histo-compatibility complex class Ia, intercellular adhesion molecule-I, glial fibrillary acidic protein, neurofilament protein, CD3 and OX42 revealed the presence of abundant microglia but not of lymphocytes or polymorphonuclear cells in the lesions. Axonal degeneration and astrogliosis were mild in degree. These pathological changes explain the observed spastic paraparesis in the rats, and represent a good model of spongiform diseases of the human central nervous system of retroviral origin, such as human T cell leukemia virus-associated myelopathy and AIDS.

Animals↗

New immunodeficient (nude-scid, beige-scid) mice as excellent recipients of human skin grafts containing intraepidermal neoplasms.

Engraftment of normal or lesional human skin onto nude or SCID (severe combined immunodeficiency) mice has been used as an in vivo experimental model. However, this model has some limitations, such as shrinkage and loss of the grafted skin over time. To improve the experimental model, we have produced two new SCID-lineage mouse strains, BALB/cA-nude-scid (nu/nu, scid/scid) and BALB/cA-beige-scid (bg/bg, scid/scid) mice, by the method of cross intercross. Intraepidermal neoplastic lesions such as Bowen's disease were grafted onto the back of the mice of these strains. The rate of reduction in the size of the grafts was lower on nude-scid and beige-scid mice than on SCID mice. Rates of survival of neoplastic cells in the grafts were higher in nude-scid mice than in SCID and beige-scid mice (SCID mice 38%, nude-scid mice 55%, beige-scid mice 38%). Neoplastic cells of Bowen's disease grafted onto a beige-scid mouse proliferated and invaded the dermis during 233 days of observation, confirming the progression to invasive squamous cell carcinoma from carcinoma in situ. The present study revealed that nude-scid and beige-scide mice newly produced by us provide a very useful in vivo experimental model for the investigation of carcinogenesis and tumor progression in human skin.

Animals↗

Campylobacter jejuni isolates from Japanese patients with Guillain-Barré syndrome.

Serologic evidence of recent Campylobacter jejuni infection was found in 92 (45%) of 205 Japanese patients with Guillain-Barré syndrome (GBS), and 49% of those 92 patients also had antibodies to GM1. Sixteen independent clinical isolates from GBS patients were serotyped: 12 belonged to Penner's heat-stable (HS) O serotype HS-19, 3 to HS-2, and 1 to HS-4. Of the patients whose C. jejuni isolates belonged to HS-19, 80% had elevated anti-GM1 antibodies. Although the correlation was significant between C. jejuni and GM1 antibody, anti-GM1 also was detected in 25% of patients without C. jejuni infection. Polymerase chain reaction-based restriction fragment length polymorphism analysis of an flaA gene showed that all HS-19 isolates, regardless of a GBS association, had an identical and distinguishable pattern, Cj-1, suggesting that HS-19:Cj-1 isolates are distinctive among C. jejuni isolates. Lectin typing showed that all GBS-associated HS-19 isolates contained terminal beta-N-acetylglucosamine residues on their cell surface, but HS-19 isolates from patients with enteritis did not.

Adolescent↗

The physiological effect of anti-GM1 antibodies on saltatory conduction and transmembrane currents in single motor axons.

Anti-ganglioside (anti-GM1) antibodies have been implicated in the pathogenesis of Guillain-Barré syndrome, multifocal motor neuropathy and motor neuron diseases. It has been held that they may interfere with saltatory conduction by blocking sodium channels. We tested this hypothesis by analysing action potentials from 140 single nerve fibres in 22 rat ventral roots using external longitudinal current measurement. High-titre anti-GM1 sera from Guillain-Barré syndrome or multifocal motor neuropathy patients, or anti-GM1 rabbit sera were applied to the rat ventral root, where saltatory conduction in single motor fibres was serially observed for 4-12 h (mean 8.2 h). For control experiments, we also tested anti-galactocerebroside (anti-GalC) sera, which causes acute demyelinative conduction block, and tetrodotoxin (TTX), a sodium channel blocker. Conduction block was found in 82% of the fibres treated with anti-GalC sera and 100% treated with TTX, but only in 2% (one out of 44) treated with the patients' sera and 5% (two out of 38) treated with rabbit anti-GM1 sera. All the nodes blocked by anti-GM1 sera revealed intense passive outward membrane current, in the internode just beyond the last active node. This pattern of current flow was similar to that in fibres blocked by demyelination with anti-GalC sera, and quite different from that seen in fibres blocked by reducing sodium currents with TTX. Our findings suggest that anti-GM1 sera neither mediate conduction block nor block sodium channels on their own. We conclude that physiological action of the antibody alone is insufficient to explain clinically observed conduction block in human diseases.

Action Potentials↗