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S Koseki

Publications and source records attributed to S Koseki.

At least 19 recordsLinked to original sources
PubMed2000

E-cadherin expression in skin tumors using an AMeX immunohistostaining method.

The AMeX (acetone-methylbenzoate-xylene) method results in good preservation of tissue and morphological details, almost equivalent to that of routinely processed formalin-fixed and paraffin-embedded tissue specimens, and of antigenicity equivalent to that of fresh frozen tissue specimens. It has been reported that the expression of the cell-cell adhesion molecule E-cadherin is often decreased in some types of carcinomas. A decrease in E-cadherin expression is associated with the invasive or metastatic potential of tumor cells. We immunohistochemically examined the expression of E-cadherin with anti-E-cadherin monoclonal antibody in various skin tumors (25 basal cell carcinomas, 11 squamous cell carcinomas, 9 keratoacanthomas, and 11 Bowen's disease) using the AMeX method and found that this method preserved antigenicity well without pretreatment. E-cadherin expression was decreased in 18.2% of squamous cell carcinomas and 33.3% of keratoacanthomas. On the other hand, it was preserved in almost all Bowen's disease and basal cell carcinomas. From the results of our study, we suggest that Bowen's disease and basal cell carcinoma do not have much metastatic potential due to retention of high levels of E-cadherin expression. We hope to apply the AMeX method to other immunohistochemical examinations because this is a very useful staining method.

Acetone↗
PubMed1999

An immunohistochemical study of E-cadherin expression in human squamous cell carcinoma of the skin: relationship between decreased expression of E-cadherin in the primary lesion and regional lymph node metastasis.

E-cadherin is a Ca(2+)-dependent, intercellular adhesion molecule that is specifically expressed in epithelial tissues and is essential for maintaining intercellular connections. It has been reported that E-cadherin expression of tumor cells is often decreased in some types of metastasizing carcinomas as compared with those without metastasis. We immunohistochemically examined the expression of E-cadherin with anti-E-cadherin monoclonal antibody and compared primary lesions of human squamous cell carcinoma of the skin (SCC) with regional lymph node metastasis to those without regional lymph node metastasis. Tumor samples from fifty-five cases of SCC (32 cases of SCC without metastasis and 23 cases with metastasis) were formalin-fixed, paraffin-embedded, and examined. E-cadherin was reduced or absent in 39 (70.9%) out of 55 cases of SCC, and in 21 (91.3%) of 23 cases with regional lymph node metastasis. Our results suggest that the decreased expression of E-cadherin in the primary lesion is correlated with regional lymph node metastasis in SCC and that it is more frequently correlated with well-differentiated than with poorly differentiated SCC. E-cadherin may be useful as a marker for metastatic potential in well-differentiated SCC.

3,3'-Diaminobenzidine↗
PubMed1999

Factors governing the activity in vivo of ribozymes transcribed by RNA polymerase III.

In order to determine the parameters that govern the activity of a ribozyme in vivo, we made a systematic analysis of chimeric tRNAVal ribozymes by measuring their cleavage activities in vitro as well as the steady-state levels of transcripts, the half-lives of transcribed tRNAVal ribozymes, and their activities in both HeLa and H9 cells. These analyses were conducted by the use of transient expression systems in HeLa cells and stable transformants that express ribozymes. Localization of transcripts appeared to be determined by the higher-order structure of each transcribed tRNAVal ribozyme. Since colocalization of the ribozyme with its target RNA is important for strong activity of the ribozyme in vivo, the best system for tRNA-based expression seems to be one in which the structure of the transcript is different from that of the natural tRNA precursor so that processing of the tRNAVal ribozyme can be avoided. At the same time, the structure of the transcript must be similar enough to allow recognition, probably by an export receptor, so that the transcript can be exported to the cytoplasm to ensure colocalization with its target. In the case of several tRNAVal ribozymes that we constructed, inspection of computer-predicted secondary structures enabled us to control the export of transcripts. We found that only a ribozyme that was transcribed at a high level and that had a sufficiently long half-life, within cells, had significant activity when used to withstand a challenge by human immunodeficiency virus type 1.

Animals↗
PubMed1999

Altered migration of gut-derived T lymphocytes after activation with concanavalin A.

Although activation of lymphocytes is known to be associated with profound changes in homing behavior, it remains unclear how activation alters migration of gut-derived lymphocytes in lymphoid and nonlymphoid organs. The objectives of this study were 1) to compare migration of naive and concanavalin A (ConA)-activated T lymphocytes into the gut mucosa, spleen, and liver and 2) to define the role of specific adhesion molecules in this homing process. Fluorescently labeled T lymphocytes collected from rat intestinal lymph were injected into the jugular vein, and the kinetics of appearance of the infused lymphocytes were monitored in ileal Peyer's patches, spleen, and liver. The migration of naive and ConA-activated T lymphocytes into microvessels were compared using an intravital microscope. ConA stimulation significantly increased the rolling velocity of T lymphocytes in postcapillary venules of Peyer's patches, and ConA-stimulated lymphocytes exhibited a loss of the selective adherence properties in Peyer's patches that is normally observed with naive T cells. ConA activation also suppressed the accumulation of T cells in the spleen. On the other hand, the adherence of T cells to hepatic sinusoidal endothelium was significantly increased after ConA activation, especially in the periportal area, and this increase was attenuated by an anti-intercellular adhesion molecule (ICAM)-1 antibody. Flow cytometry analysis revealed a decline in L-selectin expression and an increase in CD11a expression and ICAM-1 on the surface of ConA-treated T cells. In conclusion, activation of gut-derived T lymphocytes with ConA significantly alters their migration path, with a diminished localization to Peyer's patches and spleen and a preferential accumulation in hepatic sinusoids. This altered migration pattern likely results from changes in the expression of leukocyte adhesion molecules such as L-selectin and CD11a.

Animals↗
PubMed1999

[A case of multiple early gastric cancer showing complete response to UFT-E after endoscopic mucosal resection].

A 78-year-old male underwent endoscopic mucosal resection for early gastric cancer (type II a) in the anterior wall of antrum. Follow-up endoscopy showed another early gastric cancer (type II c) in the posterior wall of cardia. He refused an operation. UFT-E 300 mg/day has been administered daily since then. After 6 months, a complete tumor response was observed. The patient has been in good health without any sign of relapse for 14 months after achievement of the complete response.

Adenocarcinoma↗
PubMed1998

A simple assay system for examination of the inhibitory potential in vivo of decoy RNAs, ribozymes and other drugs by measuring the Tat-mediated transcription of a fusion gene composed of the long terminal repeat of HIV-1 and a gene for luciferase.

Nucleic acid-based drugs, including antisense RNA and DNA, ribozymes and decoys appear to have potential for the suppression of the expression of specific genes. To allow the examination of the potential of such agents in vivo as anti-HIV drugs in standard laboratories, where facilities for handling live virions are not available, we constructed a simple assay system (HIV-1 model) that allows measurement of the extent of inhibition of Tat-mediated transcription of HIV-1 by nucleic acid-based drugs and other agents. In cells that harbor a stable chimeric long terminal repeat (LTR)-Luc construct (a fusion gene consisting of the LTR of HIV-1 and the gene for luciferase), total luciferase activity in an aliquot of cell lysate is dose- and promoter-dependent on transfection with a Tat expression plasmid, reflecting the character of the LTR promoter of HIV. When HeLa cells were co-transfected with the Tat expression plasmid and another plasmid that encoded the U6 promoter or the promoter of the gene for tRNA(Val) linked to the trans-activating response (TAR) sequence, total luciferase activity was inhibited by 60 or 40%, respectively. The inhibition was also dependent on the dose of the TAR expression plasmid. These results demonstrate the usefulness of this simple assay system for detection of the efficacy of a decoy RNA or a ribozyme in vivo, without a requirement for HIV-infected cells, by measurement of luciferase activity in vitro.

Artificial Gene Fusion↗
PubMed1998

Absent myocardial accumulation of two different radioiodinated pentadecanoic acids.

This article presents two cases with preserved myocardial 201Tl uptake and absent uptake of two kinds of radioiodinated fatty acids: iodine-123-labeled 15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) and iodine-123-labeled 15-(p-iodophenyl)-9-(R,S)-methylpentadecanoic acid (9MPA). Although coronary angiography showed no stenotic lesion and left ventriculography revealed no wall motion abnormality, no myocardial uptake of BMIPP and 9MPA was observed in the first case. In the second case, no myocardial accumulation was recognized even in the initial phase of dynamic SPECT acquired soon after the injection of 9MPA. The results suggest that the non-visualized myocardium was not specific for BMIPP imaging and that rather than the early back diffusion of the tracers from the myocardium, abnormality of the myocardial cell membrane was a possible mechanism accounting for the phenomenon.

Biological Transport, Active↗
PubMed1998

Formation of a catalytically active dimer by tRNA(Val)-driven short ribozymes.

A minizyme is a hammerhead ribozyme with a short oligonucleotide linker instead of stem/loop II. Minizymes with low activity as monomers form active dimeric structures with a common stem. We explored the use of dimeric minizymes as gene-inactivating agents by placing minizymes under the control of a tRNA(Val) promoter. The tRNA(Val) portion of the transcript did not hinder dimerization as the tRNA-embedded minizyme formed an active dimeric structure. The cleavage activity of this minizyme that had been expressed either in vitro or in HeLa cells was almost one order of magnitude higher than that of the tRNA(Val)-embedded conventional hammerhead ribozyme. The tRNA(Val)-driven minizyme inhibited reporter gene activity (95%) whereas the tRNA(Val)-driven hammerhead ribozyme resulted in approximately 55% inhibition.

Base Sequence↗
PubMed1998

1alpha,24-dihydroxyvitamin D3 (tacalcitol) is effective against Hailey-Hailey disease both in vivo and in vitro.

We report a case of Hailey-Hailey disease (HHD) in which 1alpha, 24-dihydroxyvitamin D3 (tacalcitol) was effective both clinically (in vivo) and in explant cultures (in vitro) of a skin lesion. The patient was a 65-year-old man with HHD lesions in the axillary and inguinal areas bilaterally. We applied ointment containing 1alpha, 24-dihydroxyvitamin D3 (tacalcitol), an analogue of active vitamin D3, to the lesions and assessed its clinical effectiveness. The HHD lesions in both groins disappeared after treatment with the 1alpha, 24-dihydroxyvitamin D3 ointment, and the remission has continued to the present. A punch biopsy specimen of the lesion that had remitted showed no acantholysis. In addition, dissociation of migrating keratinocytes was observed when biopsy specimens of the HHD skin lesion were cultured in medium without 1alpha,24-dihydroxyvitamin D3, but inhibition of keratinocyte dissociation was observed in medium containing it. These results suggest the effectiveness of 1alpha, 24-dihydroxyvitamin D3 against HHD both in vivo and in vitro.

Aged↗
PubMed1998

Effect of physical activity on the distensibility of the aortic wall in healthy males.

To study the effect of physical activity level on the distensibility of the human aortic wall, aortic pulse wave velocity (APWV) was estimated in 139 healthy male subjects (19-67 years) and was related to the energy expenditure by habitual physical exercise (physical activity index: PAI), which was evaluated by a 7-day total activity recall. The subjects consisted of 56 fun runners (runner group) and 83 general subjects, who were divided into 25 active subjects (active group: PAI > or = 1,500 kcal/week) and 58 sedentary subjects (sedentary group: PAI < 1,500 kcal/week). The APWV index (APWVI: standardized APWV by the diastolic blood pressure) was found to be positively correlated with age and was negatively correlated with PAI. The age-adjusted APWVI of the runner group was significantly lower than that of the active and sedentary groups. The age-adjusted APWVI was also significantly lower in the active group than in the sedentary group. These results suggest that increased physical activity may retard the age-dependent loss of arterial distensibility in humans, in proportion to the amount and/or intensity of exercise.

Adult↗
PubMed1998

[Mucosal immune system of the intestine].

Gut-associated lymphoid tissue is the major inductive site of mucosal immune system, functionally independent of the systemic immune system. Particulate antigens are mainly uptaken from M cell of Peyer's patches, inducing IgA production in the intestinal mucosa. Lymphocytes are continuously recirculating through the intestinal mucosa to facilitate intestinal immune response. Dysregulation of lymphocyte migration and cytokine imbalance in the intestinal mucosa may be largely involved in the pathogenesis of inflammatory bowel diseases including intestinal allergy and Crohn's disease. There is also a possibility that dietary components especially long chain fatty acid could influence immune cell function of the intestinal mucosa. Because dietary components are closely associated with immunological function of intestinal mucosa, the importance of dietary manipulation for the management of inflammatory bowel diseases should be concerned.

Animals↗
PubMed1997

Inhibition of transcription by the TAR RNA of HIV-1 in a nuclear extract of HeLa cells.

Regulation of transcription of human immunodeficiency virus type-1 (HIV-1) requires specific interaction of Tat protein with the trans-activation response region (TAR). Inhibition of replication of HIV-1 has previously been achieved with a TAR decoy, namely a short RNA oligonucleotide that corresponded to the sequence of the authentic TAR RNA. Since TAR RNA has the potential to interact with cellular factors, we examined the effect of TAR RNA on efficiency of transcription in nuclear of HeLa cell extracts. We performed an in vitro transcription assay in the presence of authentic TAR RNA using a template that was driven by the CMV (cytomegalovirus) early promoter in a HeLa nuclear extract and found, for the first time, that TAR RNA inhibited transcription by approximately 60-70% independently of the Tat-TAR interaction. Furthermore, we evaluated inhibition of transcription by variants of TAR RNA and found that the TAR RNA loop, bases surrounding the loop, the triple base bulge and the 'lower' stem region of TAR RNA were responsible for the inhibition of transcription. Taken together, earlier reports on proteins that bind to TAR RNA and the present results suggest that integrity of TAR RNA is important for efficient binding to cellular transcription factors. As judged from the significant inhibition observed in this study, the TAR decoy might sequester transcription factors and thus it might potentially be able to inhibit transcription of housekeeping genes that are unrelated to Tat function.

Base Sequence↗
PubMed1997

A case of triple extramammary Paget's disease.

We report a 74-year-old Japanese man with triple extramammary Paget's disease; the genital and both of the axillar regions were simultaneously involved. Literature review revealed that 27 cases of triple extramammary Paget's disease have been reported in Japan, but there are no reports of triple extramammary Paget's disease from countries other than Japan, although 2 cases of double extramammary Paget's disease are reported. In all 28 cases, including our case, the genital lesion preceded the axillary lesions. All cases except one were male and only the exceptional female case was reported to have an the invasive tumor in the dermis. We speculate that extramammary Paget's disease may appear multi-centrically.

Aged↗
PubMed1997

[Blood biochemical properties in male workers analysed according to body type].

The characteristics of body type, serum lipids and blood pressure in male blue workers were evaluated. The subjects were 1,705 healthy men aged 40.3 +/- 4.33 years, and were classified into 4 groups according to body mass index: BMI; lean (group L: BMI < 20), normal (group N: 20 < or = BMI < 24), mildly obese (group MO: BMI 24 to 26.5) and obese group (group O: BMI > 26.5). The physical characteristics, blood pressure and 14 blood constituent items were measured. Groups L, N, MO and O accounted for 8.5, 53.4, 28.6, and 9.4% of all subjects, that is the obese body type (MO and O groups) occupied 38%. Rest systolic and diastolic blood pressure were positively related to BMI. Most blood constituent items biochemically analyzed increased in proportion to BMI values. The Trigriceride level was 88.5, 112.2, 152.8 and 171.9 mg/dl in groups L, N, MO and O, respectively. The Trigriceride level in groups MO and O were about the upper limit of the normal range. The total cholesterol level was in the normal range in 4 groups, but was higher in the MO and O groups than in groups L and N. The HDL-cholesterol level was low in inverse proportion to BMI, that is 58.2, 51.3, 47.6, and 42.6 mg/dl in groups L, N, MO, and O, respectively. Especially the values in group O were similar to the values in the aged and adult disease patients. A greater percentage of Japanese male workers were obese men and they risked developing atherosclerosis and adult diseases. the present study suggests that health education regarding exercise prescription and nutrition intake in daily life should be provided.

Adult↗
PubMed1995

An immunohistochemical study of lysozyme, CD-15 (Leu M1), and gross cystic disease fluid protein-15 in various skin tumors. Assessment of the specificity and sensitivity of markers of apocrine differentiation.

We investigated immunohistochemically the localization of lysozyme and Leu M1 in normal skin, 76 cases of benign sweat gland tumors, 28 cases of malignant sweat gland tumors, 23 cases of extramammary Paget's disease, 7 cases of sebaceous carcinoma, 6 cases of malignant trichilemmoma, 10 cases of squamous cell carcinoma, and 10 cases of basal cell carcinoma and compared the results with those for gross cystic disease fluid protein (GCDFP)-15 to assess the sensitivity and specificity of our assay conditions for apocrine differentiation. Normal apocrine glands were stained with all three antibodies, while eccrine glands were positive only for GCDFP-15, and other portions of normal skin were not stained with any of the antibodies used. In neoplastic tissue thought to be from apocrine tumors, antibodies raised against lysozyme and GCDFP-15 had a greater specificity (100%) for apocrine differentiation, while Leu M1 had a greater sensitivity (88%). Tissues that were stained with two or three of these antibodies appeared to exhibit apocrine differentiation. In the tumors examined, the specificity for apocrine differentiation was 100% and the sensitivity for such differentiation was 92% by these criteria. According to these criteria, some cases of syringocystadenoma papilliferum, primary mucinous carcinoma of the skin, and extramammary Paget's disease with underlying adenocarcinoma showed apocrine differentiation.

Adenocarcinoma↗
PubMed1995

Assessment of cellular proliferation of sebaceous neoplasms by AgNOR counts and immunohistochemical demonstrations of PCNA and Ki-67.

We assessed cellular proliferation of sebaceous neoplasms by AgNOR counts and the immunohistochemical demonstration of proliferating cell nuclear antigen (PCNA) and Ki-67, using formalin-fixed and paraffin-embedded tissue specimens. We used three categories of sebaceous neoplasms: four cases of sebaceoma, three cases of basal cell carcinoma with sebaceous differentiation (BCSD), and seven cases of sebaceous carcinoma (SC). Significant differences were noted between SC and non-SC tumors (sebaceoma and BCSD) in AgNOR counts and semi-quantitative grading of PCNA and Ki-67 labelling indices (P < 0.01). When a cut-off value of 6 was chosen, the AgNOR value discriminated SC from non-SC tumors with high specificity and sensitivity. When a cut-off value of 25% was chosen, PCNA and Ki-67 labelling indices also discriminated between these tumors. Significant differences were not observed between sebaceoma and BCSD with PCNA and Ki-67 labelling indices. AgNOR counts of BCSD were a little higher than those of sebaceoma, but the number of cases was too small to perform statistical assessment. We consider AgNOR counts and semi-quantitative grading of PCNA and Ki-67 labelling indices to be useful in differentiating SC from BCSD and sebaceoma.

Cell Division↗