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Biomedical subjects

Y Tagawa

Publications and source records attributed to Y Tagawa.

At least 109 records · Page 6Linked to original sources
PubMed1997

Association of Campylobacter jejuni serotype with antiganglioside antibody in Guillain-Barré syndrome and Fisher's syndrome.

Using Penner's method and Lior's scheme, we serotyped 31 isolates from patients with Guillain-Barré syndrome, 7 isolates from those with Fisher's syndrome, and isolates from patients with sporadic enteritis. PEN 19 of Campylobacter jejuni was isolated more frequently from the Guillain-Barré syndrome patients (16/31 isolates, 52%) than from the sporadic enteritis patients (5%). LIO 7 of C. jejuni also was isolated more frequently from the Gillain-Barré syndrome patients (14/31 isolates, 45%) than from the enteritis patients (3%). One reason why Guillain-Barré syndrome is rare, despite the high incidence of C. jejuni enteritis, may be the low frequencies of PEN 19 and LIO 7. The frequency of positive anti-GM1 antibody titers in the Guillain-Barré syndrome patients with PEN 19 isolates was higher than that in the Guillain-Barré syndrome and Fisher's syndrome patients without PEN 19 isolates. We speculate that the serotypic determinant of PEN 19 aids in the production of anti-GM1 antibody by a GM1-like lipopolysaccharide. In contrast, 5 of the 7 isolates from the Fisher's syndrome patients belonged to PEN 2:LIO 4. The IgG anti-GQ1b antibody was associated with PEN 2 and LIO 4. These serotypic determinants may aid in the production of IgG anti-GQ1b antibody by a GQ1b-like lipopolysaccharide.

Antibodies↗
PubMed1997

Analysis of p53 gene deletions in colorectal cancers using fluorescence in situ hybridization.

To examine the relationship between the incidence of p53 gene deletion in each nucleus and the clinicopathological features in colorectal cancers, we performed a cytogenetic study using fluorescence in situ hybridization (FISH). FISH was performed on 5 adenomas and 38 colorectal cancers that had been resected surgically. The nucleus, in which the copy number of the p53 signal was lower than that of chromosome 17, was determined as a deletion of the p53 gene. The mean frequency of the deletion of p53 in adenomas and cancers were 7.8% +/- 3.0% and 57.0% +/- 19.0%, respectively. Numerical aberrations of chromosome 17 or a deletion of p53 were also detected in DNA diploidy. The mean frequency of the deletion of p53 in 32 cases with aneusomy of chromosome 17 (65.7% +/- 14.5%) was significantly higher than that in cases of disomy (51.1% +/- 19.3%, P < 0.05). Even though this frequency was high in the early stage, it was not associated with any specific histopathological features. This frequency was also higher in double primary cancers (70.4% +/- 16.7%) compared with single colorectal cancers (53.4% +/- 18.1%) (P < 0.05). Using FISH, our results demonstrated that the clonal deletion of the p53 locus is an early genetic event of colorectal cancers and that a high incidence of p53 deletion may influence the occurrence of double primary cancers.

Adenoma↗
PubMed1997

Aneusomy of chromosome 18 is associated with the development of colorectal carcinoma.

Specific loss of heterozygosity of chromosome 18 has been observed frequently in advanced colorectal carcinoma and is closely associated with its development. We investigated the prevalence of numerical aberrations of chromosome 18 in 44 specimens of colorectal carcinomas, using fluorescence in situ hybridization. We also examined the relationship between aneusomy of chromosome 18 and the clinicopathological features of these tumors. Aneusomy of the specimens (monosomy and polysomy) was determined when the same aneusomic population was detected in more than 15% of the nuclei. The frequency of monosomy and polysomy of chromosome 18 in colorectal carcinomas was 43% (19/44) and 29% (12/44), respectively. The prevalence of monosomy and polysomy 18 was significantly higher in cancers with invasion exceeding category T2 compared with T1 (P < 0.01), and with tumor size exceeding 20 mm in diameter compared with tumors less than 20 mm (P < 0.05). However, the prevalence of aneusomy 18 was not associated with other clinico-pathological features. The mean survival period and the 5-year survival rate after operation in patients with aneusomy 18 was not different from findings for those with disomy 18. Our results indicate that aneusomy of chromosome 18 is associated with the development of colorectal carcinoma; however, it is not a useful indicator of postoperative prognosis.

Adult↗
PubMed1997

Pathogenesis of the neurotoxicity caused by anti-GD2 antibody therapy.

After treatment of melanomas with anti-GD2 monoclonal antibody (MAb) (14G2a), some patients develop sensorimotor demyelinating polyneuropathy with and without the syndrome of inappropriate antidiuretic hormone (SIADH). To clarify what causes the neurotoxicity of anti-GD2 MAb, we investigated the immunohistochemical localization of GD2 in the human nervous system. Anti-GD2 MAb (14G2a) reacted with the myelin sheaths in the peripheral nerves as well as with the pituicyte cytoplasm in the posterior lobe of the pituitary gland. We assume that the binding of anti-GD2 MAb to peripheral nerve myelin and the pituicytes in the posterior pituitary causes sensorimotor demyelinating neuropathy and SIADH.

Animals↗
PubMed1997

Close association of Guillain-Barré syndrome with antibodies to minor monosialogangliosides GM1b and GM1 alpha.

Cumulative evidence supports the theory that anti-ganglioside antibodies function in the development of Guillain-Barré syndrome (GBS). Some patients have developed GBS after the administration of monosialoganglioside extracted from bovine brain. To clarify the pathogenesis of GBS associated with and without administration of the monosialoganglioside fraction, we investigated serum antibodies to the minor monosialogangliosides GM1b and GM1 alpha in patients with GBS and in control patients. GM1b and GM1 alpha were recognized specifically by the IgG antibody from the GBS patients. Twelve of 20 GBS patients who had high IgG anti-GM1b antibody titers had a preceding gastrointestinal infection. To evaluate the hypothesis that GM1b could be an immunogen, we determined whether a GM1b epitope was present in Campylobacter jejuni isolated from a patient with GBS associated with anti-GM1b antibody. Immunostaining with the monoclonal anti-GM1b antibody indicated that the lipopolysaccharide of the C. jejuni strain has the GM1b epitope. We speculate that an injection of bovine GM1 fraction that contains GM1b, as well as infection by an agent that bears the GM1b epitope, induces production of the anti-GM1b antibody which functions in the development of GBS in some patients.

Animals↗
PubMed1997

Cholinergic neuron-specific ganglioside GQ1b alpha a possible target molecule for serum IgM antibodies in some patients with sensory ataxia.

In neurological diseases the presence of certain anti-glycosphingolipid antibody species is associated with the clinical features. We recently isolated the novel cholinergic neuron-specific gangliosides GQ1b alpha and GT1a alpha from bovine brain. A monoclonal antibody specific for GQ1b alpha and GT1a alpha reacted strongly with the dorsal born of human spinal cord but not with human motor neurons. We investigated the serum antibodies to these minor gangliosides in a number of neurologic diseases and found that 4 patients with sensory ataxic neuropathy had a remarkably high IgM anti-GQ1b alpha antibody titer. GQ1b alpha may be a target molecule for serum IgM antibodies in some patients with sensory ataxic neuropathy.

Animals↗
PubMed1997

Expression of macrophage migration inhibitory factor in rat retina and its immunohistochemical localization.

Macrophage migration inhibitory factor (MIF) plays an important regulatory role for the T-cell activation induced by mitogenic or antigenic stimuli. We examined expression of MIF in rat retina. Reverse transcription-polymerase chain reaction analysis of a retinal tissue homogenate revealed that MIF mRNA was constitutively expressed. A single band specific for MIF protein was also observed by Western blot analysis. Immunohistochemistry using frozen sections of retinal tissues reacted with an anti-rat MIF antibody showed that MIF was localized in astrocytes. Müller cells and pigment epithelial (RPE) cells. This topological finding was confirmed by colocalization of MIF protein with glial fibrillary acidic protein and vimentin, which are putative immunohistochemical markers for astrocytes and Müller cells. It is well known that the retinal glial cells, as well as RPE cells, play an active role in inflammatory and immunological responses in the retina. Considering these facts, constitutive expression of MIF in these cells suggested the possibility that the protein contributes to regulation of retinal tissue inflammation as well as its local immunity.

Animals↗
PubMed1997

Gain of chromosome 20 is a frequent aberration in liver metastasis of colorectal cancers.

To investigate the characteristics of the numerical chromosome aberrations in liver metastasis of colorectal cancers, fluorescence in situ hybridization (FISH) for chromosomes 8, 18, 14/22, and 20 was performed in 18 specimens of primary regions and 18 of metastatic regions in liver metastasis of colorectal cancers compared with 15 of non-liver metastatic cancers. Among these numerical aberrations, the gain of chromosome 20, especially copy numbers exceeding three, was frequently observed in primary and metastatic cancers. Among these numerical aberrations, the gain of chromosome 20, especially copy numbers exceeding three, was frequently observed in primary and metastatic regions of liver metastasis groups compared with that of the non-liver metastasis group (P < 0.05). The incidences of gain of chromosome 20 in both regions of the liver metastasis group were higher than that of the non-liver metastasis group (P < 0.05). The gain of chromosome 20 is a frequent aberration in primary and metastatic regions in patients with liver metastatic colorectal cancers and may be available as a genetic marker for the diagnosis or prediction of liver metastasis.

Case-Control Studies↗
PubMed1997

A sighted man with non-24-hour sleep-wake syndrome shows damped plasma melatonin rhythm.

Twenty-four-hour profiles of plasma melatonin, cortisol and rectal temperature were measured longitudinally in a sighted man who has been suffering from sleep disorders for more than 10 years. The sleep-wake rhythm of this subject free-ran, despite his routine life, and occasionally showed a sign of internal desynchronization, where sleep was lengthened up to 30 h. These states were classified into the non-24-hour sleep-wake syndrome. Plasma melatonin concentrations in the subjective night remained at a low level and showed a damped circadian rhythm. At the same time, robust circadian rhythms were detected in plasma cortisol and rectal temperature, indicating that the circadian pacemaker was intact. The causal relationship between the damping of nocturnal melatonin rise and a failure of entrainment of the sleep-wake cycle is discussed.

Adult↗
PubMed1997

The whole nucleotide sequence and chromosomal localization of the gene for human metabotropic glutamate receptor subtype 6.

Metabotropic glutamate receptor subtype 6 (mGluR6) is restrictedly expressed in the retinal ON bipolar cells and ablation of mouse mGluR6 by gene targeting results in a loss of ON responses to light stimulus and impairs the detection of visual contrasts. We have isolated genomic clones containing the human mGluR6 gene and determined the whole nucleotide sequence of the mGluR6 gene. The transcription initiation site of the human mGluR6 gene has been identified using primer extension analysis in combination with reverse transcriptase-mediated polymerase chain reaction analysis of human retinal RNA, while the termination of the mGluR6 mRNA has been assigned by the analysis of rapid amplification of 3'-cDNA ends. The human mGluR6 gene consists of 16,742 base pairs with 10 exons separated by nine introns. The human mGluR6 is composed of 877 amino acid residues with a signal peptide of 24 amino acid residues and the mature protein shows a 94.6% homology with the rat counterpart. A CpG-rich island is present at exon 1 and its preceding putative promoter region and this unusual sequence, like several tissue-specific genes, may be important for a specific expression of the mGluR6 gene in the retinal bipolar cells. The human mGluR6 gene has been mapped to chromosome 5q35 by the analyses of blot hybridization of a DNA panel of human/mouse/hamster somatic cell hybrids and fluorescence in situ hybridization of human chromosomes. This study should provide the genetic basis for not only better understanding the molecular mechanism underlying a tissue-specific expression of the mGluR6 gene but also exploring a potential defect in human mGluR6 in a certain inherited eye disease.

Amino Acid Sequence↗
PubMed1997

Ability to remove immunoglobulins and antiganglioside antibodies by double filtration plasmapheresis in Guillain-Barré syndrome: is it equivalent to plasma exchange?

The value of plasma exchange (PE) in Guillain-Barré syndrome (GBS) is well established. In Japan, patients with GBS and related diseases often receive double filtration plasmapheresis (DFPP) as well as PE. No comparative trials between PE and DFPP, however, have been conducted. We compared their abilities to remove immunoglobulins and antiganglioside antibodies to find out whether DFPP is equivalent to PE. The ability to remove immunoglobulins and antiganglioside antibodies was compared between PE and DFPP using plasma samples from 41 patients with GBS and related diseases before and after each treatment session. The ability of DFPP to remove both IgGs and antiganglioside IgG antibodies were significantly inferior to those of PE. There is a less theoretical basis for selecting DFPP as the first choice of plasmapheresis for GBS and related disorders.

Aged↗
PubMed1997

Two patients with acute Guillain-Barré syndrome treated with different apheresis methods.

We treated 2 patients with severe acute Guillain-Barré syndrome (GBS) with different apheresis methods. Sera from these patients in the acute phase contained a high titer of immunoglobulin (Ig)G anti-GM1 ganglioside antibody. One was a 57-year-old female treated with immunoadsorption (IA). IgG anti-GM1 antibody titer was reduced from 1:102,400 to 1:6,400 measured by ELISA after 1 month. However, her residual deficit was severe. The other patient was a 43-year-old male treated with plasma exchange (PE). IgG anti-GM1 antibody was reduced from 1:3,200 to 1:400 after 1 session of PE. After 1 month, he could walk independently. The better prognosis of the latter was possibly because of the patient's younger age and the plasma exchange that might have reduced such pathogenic factors as antiganglioside antibodies at the early stage of GBS.

Acute Disease↗
PubMed1997

Deletion of chromosome 11 and development of colorectal carcinoma.

The deletion of chromosome 11q is observed frequently in tumors of the large intestine. To investigate the relationship between aberrations of chromosome 11 and histopathological features of colorectal carcinoma, we examined the frequency of chromosome aberrations using fluorescence in situ hybridization to 29 short-term cultured cells from surgical specimens. Numerical aberrations were not related to any factors. The deletion of chromosome 11 was frequently observed in larger (> or = 5 cm) and more invasive tumors (> or = T3 category) (p < 0.05). Furthermore, the incidence of aberrations tended to increase in Dukes' B. Although translocation of chromosome 11 was also found in 17% of cases, it was not associated with histopathological features. Our findings indicate that the deletion of chromosome 11 is closely related to the progression of colorectal carcinoma.

Chromosome Aberrations↗
PubMed1997

Expression of macrophage migration inhibitory factor in corneal wound healing in rats.

PURPOSE: The study was conducted to evaluate the expression of macrophage migration inhibitory factor (MIF) during penetrating corneal injury. METHOD: A penetrating linear incision (2 mm) was made in the center of the right cornea with a razor blade. The expression of MIF in the lacerated eye and in the contralateral eye was examined by immunohistochemistry at 3, 6, 24, 48, and 72 hours after injury. Concentrations of MIF in the aqueous humor of the injured and contralateral eyes were also measured by enzyme-linked immunosorbent assay. The expression of MIF messenger RNA (mRNA) in the injured cornea was quantified by reverse transcription-polymerase chain reaction and subsequent Southern blot analysis. RESULTS: Positive migration inhibitory factor staining was observed in the basal cells of epithelial and endothelial cells of the normal rat cornea. The positive staining of the central corneal epithelium diminished at 3 hours after injury. At 6 hours after injury, positive MIF staining reappeared on the basal cells of the injured area, whereas the staining of the contralateral eye remained unchanged. Enzyme-linked immunosorbent assay of the aqueous humor revealed that the MIF concentration was elevated in both the injured and the contralateral eyes. The maximum concentration of aqueous MIF was observed at 6 hours after injury in both eyes. Reverse transcription-polymerase chain reaction and Southern blot analysis revealed that MIF-mRNA expression in the injured cornea increased from 6 to 48 hours after injury. CONCLUSION: The results of immunohistochemistry suggest the possibility that MIF is released from the corneal epithelial cells of the injured eye within 3 hours. Conversely, the MIF-mRNA level of the injured cornea is increased from 6 to 48 hours after injury and then diminished. In addition, unilateral corneal injury induces bilateral upregulation of MIF in the aqueous humor.

Animals↗
PubMed1997

[p53 alterations and chromosome 17 aberrations in non-small cell lung cancer].

We studied the relationship between DNA index, numerical abberation of chromosome 17 and alterations of the p53 gene in 23 non-small cell lung cancers. Diploid and aneuploid cells from 23 non-small cell lung cancer with DNA aneuploidy were flow sorted into each cell population using FACStar(plus). They were examined by PCR-SSCP analysis for p53 mutation and by microsatellite analysis for loss of heterozygosity at TP53 locus (17p13.1). They were also analyzed by FISH for copy number of chromosome 17. p53 mutations were found in aneuploid cells from the 11 cases (48%). Among them, 8 cases were informative at TP53 locus, and all showed loss of heterozygosity. Aneuploid cells from 16 cases exhibited gain of chromosome 17 copy number in FISH analysis. DNA index was significantly associated with th mean copy number of chromosome 17, suggesting that the number of chromosome 17 changed with DNA index. There were no associations between p53 mutation and DNA index or mean copy number of chromosome 17. In some cases, we also analyzed structural abberation of short arm of chromosome 17 by FISH using p53-cosmid (17p13.1) and Distal 17p (17p13.3-ptel) probes. The p53 gene located on the increased chromosome 17 was lost due to point mutation or deletion of 17p.

Aneuploidy↗
PubMed1997

[Numerical aberration of chromosome 17 is correlated with multiple primary cancer in colorectal carcinoma].

Numerical aberration of chromosome 17 of 14 cases of colorectal carcinoma with multiple primary cancer (: multiple cancer) was compared with that of 35 cases of colorectal carcinoma without any other cancer (: single cancer). Fluorescence in situ hybridization with p17H8 was performed on touch smear from fresh materials. The proportion of aneusomy 17 (NCAI: numerical chromosome aberration index) in multiple cancers was significantly higher than that of single cancers (37.7 +/- 10.5% VS 46.1 +/- 8.0%; p < 0.01). Although NCAI of single cancers conformed to cancer progression (26.1 +/- 4.7% in Dukes A, 33.1 +/- 7.1% in Dukes B, 39.9 +/- 6.9% in Dukes C, and 45.7 +/- 12.0% in Dukes D), that of multiple cancers was high in all stages (44.7 +/- 7.3%, 44.4 +/- 6.8%, 50.4 +/- 11.2%, and 49.6 +/- 5.6%, respectively). Furthermore, the multiple numerical aberration of chromosome 17 in multiple cancers was more often than that of single cancers (64.3% VS 22.9%; p < 0.01).

Aged↗