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Y Ichikawa

Publications and source records attributed to Y Ichikawa.

At least 19 recordsLinked to original sources
PubMed2006

Transcription-reverse transcription concerted reaction and minimal residual disease in axillary sentinel nodes of breast cancer.

AIMS: To investigate the use of transcription-reverse transcription concerted reaction (TRC) to detect axillary lymph node metastases. METHODS: Metastases in 423 lymph nodes obtained from 50 breast cancer patients were investigated by routine pathological hematoxylin and eosin (H and E) staining and quantitative analysis of carcinoembryonic antigen (CEA) mRNA by TRC. Enhanced pathological studies, serial sectioning and immunohistochemistry were conducted for cases which were negative by routine pathology, but positive by TRC. RESULTS: Pathological examination identified metastatic disease in 67 lymph nodes. TRC CEA mRNA results were concordant with 89.8% of these cases at a threshold of 100 copies. TRC identified 30 false negative nodes, which was reduced to 15 by excluding node biopsies yielding less than 40 microg total RNA. Twelve nodes were histologically negative for cancer, but positive according to TRC. Serial sectioning and immunohistochemical analysis of these nodes revealed macrometastatic lesions in three, micrometastasis in one, and isolated tumor cells in two. CONCLUSION: TRC for the detection of CEA mRNA may complement routine pathological examination by sentinel lymph node biopsy (SNB) in early breast cancer. We have started an enhanced pathological examination with serial sectioning on all excised sentinel nodes to set the best threshold for the TRC method.

Adult↗
PubMed2006

Retrospective study of the effects of cyclosporine in comparison with azathioprine on renal transplant recipients infected with hepatitis C virus.

A recent report noted that cyclosporine (CsA) inhibits replication of the hepatitis C virus (HCV) in vitro. Thus, CsA may be a superior immunosuppressant for renal transplant recipients infected with HCV. In the present retrospective study, we assessed whether CsA reduced the clinical impact of HCV infection among those patients. A total of 405 renal transplants were performed between 1973 and 2005, of whom we studied 189 who received CsA-based immunosuppression (CsA group) vs 108 who received an azathioprine-based regimen (AZA group). There were 44 HCVAb carriers and 145 noncarriers in the CsA group, and 41 carriers and 67 noncarriers in the AZA group. Our results showed that patient survival rate was significantly worse among HCVAb carriers than among noncarriers, as the overall survival rates were 82.9% and 90.9%, respectively, after 10 years and 71.5% and 85.7%, respectively, after 20 years (P = .0003). Patient survival rates were also significantly worse in HCVAb carriers than in noncarriers in both groups, which were 83.2% and 95.0%, respectively, after 10 years, and 74.7% and 88.8%, respectively, after 20 years (P = .0147) in the CsA group, and 82.9% and 83.6%, respectively, after 10 years and 70.7% and 80.6%, respectively, after 20 years (P = .0171) in the AZA group. Conversely, no significant difference was seen in patient survival rate for HCVAb carriers between the two groups (83.2% vs 82.9% at 10 years, and 74.7% vs 70.7% at 20 years, P = .8195). Our results confirmed that HCV infection has a negative impact on the long-term survival of renal transplant patients who receive either a CsA-based or an AZA-based regimen, suggesting that CsA does not have a positive impact on HCV carriers.

Adult↗
PubMed2006

Kidney transplantation in patients receiving dialysis treatment for more than 10 years.

In the present single center study, we analyzed 277 kidney transplant patients (procedures performed between February 1984 and February 2006) to determine the impact of long-term dialysis on kidney transplant outcomes. Forty-four had been treated prior to renal transplantation with dialysis for more than 10 years (range, 10.0-32.5 years, average, 16.6 years; Group I), while the remaining 233 recipients showed an average end-stage renal disease period of 2.8 years (range, 0-9.8 years; Group II). There were no significant differences in patient survivals between the 2 groups: 97.3% vs 97.4% at 1 year; 85.7% vs 92.4% at 5 years; 85.7% vs 90.7% at 10 years (P = .2347). Five Group I patients died: 2 from infections, 2 from liver dysfunction, and 1 from cerebral bleeding. These causes of death were similar to those among Group II patients. Graft survival was not significantly different between the 2 groups: 95% vs 88.8% at 1 year; 75.5% vs 76.5% at 5 years; 75.5% vs 65.5% at 10 years (P = .6264). Our results suggested that dialysis treatment for more than 10 years did not have negative effects on posttransplantation patient and graft survival.

Adult↗
PubMed2005

Blue-dye technique complements four-node sampling for early breast cancer.

AIMS: To examine four-node axillary sampling assisted by a blue dye (4NAS/dye) technique as a sentinel node biopsy (SNB) for breast cancer. METHODS: Lymphatic mapping was performed by injection of patent blue for 33 consecutive cases with breast cancer. Axillary sampling was performed until four nodes were obtained. This was followed by back-up axillary lymph node dissection to examine the feasibility of 4NAS/dye. The same study with 30 cases was conducted at an independent hospital to confirm the feasibility of this method. This method was then applied to 101 consecutive clinically node-negative patients to avoid axillary-node dissection, with intraoperative diagnosis made by frozen section examination. RESULTS: The median numbers of blue-stained nodes and nodes excised by 4NAS/dye were 1.7 and 3.4, respectively. The identification rate of sentinel lymph nodes (SNs) was 81.8% using the dye alone and 97.0% when the combination was used. Pathological examination revealed that the nodal status was correctly predicted by the dye alone in 62.5% of cases with metastasis, whereas in 100% by 4NAS/dye. The dye alone was not sufficient to identify SNs, especially in cases with prior excisional biopsy. The identification rate of SNs and the accuracy rate in another feasibility study were 100% and 92.5% in 30 consecutive cases, respectively. 4NAS/dye successfully detected SNs in 100 of 101 cases of the subsequent observational study with an acceptable post-operative axillary morbidity and thus succeeded as an SNB. CONCLUSIONS: The 4NAS/dye method is reliable for the detection of SNs. This method could be applied to observational studies without radio-isotope.

Adult↗
PubMed2004

Effect of formalin on extraction of mRNA from a formalin-fixed sample: a basic investigation.

BACKGROUND: The validity of molecular studies using RNA extracted from decades-old formalin-fixed and embedded tissue blocks is well documented. Formalin-fixed samples are, however, known to be poor materials for molecular biological applications. The aim of this study was to investigate the effect of formalin as a preservation agent on RNA quality and relevant molecular applications. METHODS: The quantity and quality of RNA from liver tissues are modified by the fixation time. Rat liver tissues were harvested and fixed for 4, 8, 12, and 24 h in 10% buffer formalin, and only 9% of RNA could be extracted from the formalin-fixed tissue stored for 4 h. RESULTS: Agarose gel electrophoresis did not show the characteristic pattern of RNA with 18S and 28S in all lanes. Based on the results, it is thought that the RNA was damaged owing to one or more of the following reasons: 1) formalin directly degrades RNA, 2) formalin inactivates RNase, and/or 3) formalin destroys the reagent for extraction of RNA. In this study, it was shown by electrophoresis that very little RNA was extracted by Trizol with 1% formalin. CONCLUSIONS: Formalin has direct and indirect ill effects on RNA during the extraction process.

Animals↗
PubMed2004

Gene expression profile analysis of regenerating liver after portal vein ligation in rats by a cDNA microarray system.

AIMS: We assessed changes in gene expression of hypertrophied liver after portal vein ligation (PL) in a test group of rats compared to a control group, which had the same size liver but no PL. METHODS: The portal veins of the left and median lobes in the test group were ligated in an initial operation. Four days after the PL, the liver volume of the posterior caudate lobe (5%) increased two-fold and comprised 10% of the liver. A 90% hepatectomy was then performed, leaving only the hypertrophied posterior caudate lobe, and leaving the normal anterior and posterior caudate lobes (10%) in the control (sham) group. A comparison of the expression profiles between two groups was performed using cDNA microarrays and the hepatic ATP level was measured. RESULTS: The survival rate for the PL group was significantly higher than for the sham group at 4 days after the hepatectomy (56.3% and 26.7%, P < 0.05). Gene expression of cyclin D1, proliferating cell nuclear antigen, cyclin A and B was upregulated, and the cyclin-dependent kinase inhibitor was downregulated. Increases were observed in: (i) pyruvate dehydrogenase, the tricarboxylic acid cycle cycle regulator, (ii) acyl-CoA dehydrogenase, the oxidation regulator, and (iii) cytochrome oxidases, the oxidative phosphorylation regulator. Hepatic ATP concentration after hepatectomy was better maintained in the PL group than in the sham group (0.48 +/- 0.01 micromol/ml vs. 0.33 +/- 0.01 micromol/ml, P < 0.05). CONCLUSION: The regenerating liver increased tolerance for extended hepatectomy compared to normal liver. It is believed that this is because the induced rapid regeneration of the remaining liver after hepatectomy increases ATP metabolism.

Adenosine Triphosphate↗
PubMed2003

Ultrasound diagnosis of uterine arteriovenous fistula associated with placental site trophoblastic tumor.

We report a case of a woman with abnormal vaginal bleeding who had a placental site trophoblastic tumor (PSTT) detected following hysterectomy. Surgery was performed because of a large uterine arteriovenous fistula detected by transvaginal color and pulsed Doppler sonography. Color Doppler sonography revealed a lacunar-type lesion with a marked increase in uterine vascularity, and pulsed Doppler sonography demonstrated a low resistance index. This vascular pattern indicated the formation of blood lacunae and arteriovenous shunts caused by PSTT within the uterine myometrium. This is the first report to describe the ultrasound findings in a case of PSTT complicated by a uterine arteriovenous fistula.

Adult↗
PubMed2003

Evaluation of mutans streptococci in plaque and saliva: correlation with caries development in preschool children.

OBJECTIVES: To test the ability of a site-specific method of evaluating mutans streptococci (MS) present in plaque in order to predict caries risk in children and to compare the results with those obtained from estimating the levels of MS present in saliva. METHODS: Caries prevalence was examined twice, 6 months apart, in 129 preschool children ranging in age from 1.5 to 5. A commercial strip method was used to evaluate the MS score (0-3) in plaque collected from four selected tooth surfaces at two interdental spaces and in saliva. RESULTS: The screening criteria of the MS score for caries incidence between scores 1 and 2, and scores 0 and 1 were the most valid for evaluating plaque (accuracy of prediction, 80%) and saliva (accuracy of prediction, 71%), respectively. Based on these screening criteria, the evaluation of saliva MS was invalid when the plaque MS score was considered. Screening plaque MS was effective, regardless of caries experience at baseline, according to the chi-square test (p<0.01), but screening saliva MS was ineffective when caries experience was present at baseline. A multivariate logistic regression analysis including six variables showed that the plaque MS score and caries experience at baseline were significantly correlated with caries incidence: caries experience at baseline (OR=5.02, 95%CI: 1.81-14.59) and high plaque MS score (2 or 3) (OR=12.59, 95%CI: 3.18-67.08). CONCLUSIONS: These results suggest that the semi-quantitative evaluation of plaque MS sampled from only two proximal sites on the molars is more effective for screening preschool children at a high risk of developing caries in their primary dentition than other important caries risk indicators.

Chi-Square Distribution↗
PubMed2003

MRI in ALS patients.

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Amyotrophic Lateral Sclerosis↗
PubMed2003

The presence and longevity of peripherally expanded donor-derived TCRalphabeta+ mature T lymphocyte clones after allogeneic bone marrow transplantation for adult myeloid leukemias.

There are two major pathways for T-cell regeneration after allogeneic bone marrow transplantation; thymus-dependent T-cell differentiation of T-cell progenitors, and peripheral expansion of mature T cells in the graft. In order to learn to what extent the peripheral expansion of donor-derived mature T lymphocytes contributes to reconstitution of the TCRalphabeta+ T-cell repertoire after allogeneic bone marrow transplantation for adult myeloid leukemias, we pursued the fate of donor-derived T-cell clones using the amino-acid sequences of the complementarity-determining region 3 (CDR3) of the TCR-beta chain as a clonal marker. Clonal expansion of TCRalphabeta+ T lymphocytes with specific TCRBV subfamilies was identified in donor blood. Identical T-cell clones were not found in blood from recipients before transplantation. The donor-derived T-cell clones were identified in the circulating blood from recipients a few months after allogeneic bone marrow transplantation, and they remained in the blood for 18 months after transplant in two recipients, and for 56 months in one. These results suggest that the peripheral expansion of mature T lymphocytes in the graft makes a significant contribution to post-transplant T-cell regeneration during the early period of transplantation in humans, and that mature T cells can survive in recipients for several years. Further investigation will be required to explore which antigens drive the expansion of T-cell clones in donors and recipients, and the mechanisms of maintaining homeostatic balance between the thymus-dependent pathway and the peripheral expansion of mature T cells in post-transplant T-cell regeneration.

Adult↗