Biomedical subjects

Yasuhiro Ito

Publications and source records attributed to Yasuhiro Ito.

At least 37 records · Page 2Linked to original sources

PubMed2006

Usefulness of ultrasonography for diagnosis of malignant lymphoma of the thyroid.

BACKGROUND: Recent developments in ultrasonography (US) and the prevalence of ultrasound-guided fine needle aspiration biopsy (US-FNAB) has enabled physicians to detect and diagnosis thyroid diseases, including thyroid malignant lymphoma, much more easily. METHODS: We describe our diagnostic strategy for malignant lymphoma on US screening. We screened possible malignant lymphoma patients by US characteristics such as enhanced posterior echoes. RESULTS: Among 170 patients suspected of malignant lymphoma between 2000 and 2004, 74 (43.5%) were also diagnosed as having or suspected of lymphoma by US-FNAB. Five patients dropped out, and 67 of 69 patients who underwent surgical examination were pathologically diagnosed as having lymphoma. Finally, 79 (47.9%) of 165 US-suspected patients were confirmed as having lymphoma. Only 21.5% of lymphoma patients complained of rapidly growing goiter. CONCLUSION: US screening for goiters contributes markedly to diagnosis of lymphoma at an early phase, facilitating early initiation of therapy.

Adult↗

PubMed2006

Ethylene biosynthesis regulation in tomato fruit from the F1 hybrid of the ripening inhibitor (rin) mutant.

We have previously shown a significant decrease in the ethylene production in tomato fruit from the RIN/rin genotype. In this present study, we evaluated the amount of 1-aminocyclopropane-1-carboxylic acid (ACC) and the gene expression and enzymatic activities of ACC synthase (ACS) and ACC oxidase (ACO) to find which type of regulation influenced this low ethylene production. The results suggest that the decreased ethylene production was due to transcriptional regulation of the ACS and ACO genes by the heterozygous effect of the rin gene.

Amino Acid Oxidoreductases↗

PubMed2006

Reduction of allergenic proteins by the effect of the ripening inhibitor (rin) mutant gene in an F1 hybrid of the rin mutant tomato.

The ripening inhibitor (rin) mutant tomato yields non-ripening fruit, and the rin hybrid fruit (RIN/rin) shows an intermediate phenotype between the wild and mutant fruit, that is, red-ripe and extended shelf life. We found by a microarray analysis that the genes encoding possible allergenic proteins were expressed at a significantly lower level in the rin hybrid fruit than in the wild-type fruit. These allergenic proteins, which were beta-fructofuranosidase and polygalacturonase 2A (PG-2A), were confirmed to accumulate at a lower level in the rin hybrid fruit than in the wild-type fruit. The immunoglobulin E (IgE) in serum from a tomato-allergic patient showed lower reactivity to the extract of the rin hybrid fruit than to that of the wild fruit. These results suggest that the rin gene has the potential to regulate allergen accumulation in tomato fruit.

Antigens, Plant↗

PubMed2006

[A partial response to combined TS-1 and docetaxel chemotherapy enabling a curative resection after the failure of combined TS-1 and CDDP chemotherapy in a patient with unresectable gastric cancer].

A 60-year-old man visited our hospital complaining of epigastric pain. Gastrofiberscopy revealed an advanced gastric cancer located on the anterior wall of the antrum. Abdominal computed tomography (CT) revealed metastases to the paraaortic lymph nodes. The patient subsequently underwent combined chemotherapy consisting of TS-1 and low-dose CDDP for the treatment of unresectable gastric cancer. No reductions in the paraaortic lymph node metastases were noted after one cycle. The patient was then treated with TS-1 combined with docetaxel as a second-line chemotherapy. TS-1 (80 mg/m2) was orally administered for 2 weeks followed by a 2 week interval, while docetaxel (25 mg/m2) was simultaneously administered weekly (days 1, 8, and 15). One cycle of chemotherapy was 28 days. An abdominal CT revealed a partial response after 3 cycles. The patient experienced grade 2 leukocytopenia and grade 3 neutropenia. We decided that the patient could undergo a curative resection, and a distal gastrectomy with D2+para-aortic LN dissection was performed. The pathological efficacy was Grade 2. The patient is presently alive with no sign of recurrence after 20 months. Combined TS-1 and docetaxel chemotherapy is a promising second-line regimen for the treatment of unresectable gastric cancer, after treatment with TS 1 combined with CDDP has failed.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2005

Differentiation of follicular thyroid adenoma from carcinoma by means of gene expression profiling with adapter-tagged competitive polymerase chain reaction.

OBJECTIVE: Since preoperative differentiation between follicular thyroid adenoma (FTA) and carcinoma (FTC) remains very difficult, the purpose of this study was to identify the genes differentially expressed in FTA and FTC in order to construct a diagnostic system based on such genes for differentiation of FTA and FTC. METHODS: Gene expression profiles of 45 FTAs and 22 FTCs were analyzed by means of adapter-tagged competitive polymerase chain reaction (ATAC-PCR) with 2,516 genes (learning set). The genes differentially expressed in FTAs and FTCs were then used to construct a diagnostic system based on the weighted-voting algorithm. In addition, a validation study of this diagnostic system was conducted using 12 FTAs and 6 FTCs (validation set). RESULTS: The diagnostic system for differentiation of FTA and FTC, constructed with the aid of the learning set samples, was based on 60 genes differentially expressed in FTA and FTC, which included several genes previously identified as overexpressed in FTC (DPP4, KRT19 and IGFBP3) or FTA (trefoil factor 3 and thyroid peroxidase). The leave-one-out cross-validation study showed that the accuracy of this diagnostic system was as high as 90% (sensitivity: 77.3% and specificity: 95.6%), and was confirmed by the validation study (diagnostic accuracy: 83.3%; 95% confidence interval: 62.8-95.4%, sensitivity: 66.7% and specificity: 91.2%). CONCLUSIONS: This diagnostic system using the ATAC-PCR assay is expected to be clinically useful for preoperative differentiation between FTA and FTC since ATAC-PCR can be used for the small amount of RNA obtained from fine needle aspiration biopsy.

Adenoma↗

PubMed2005

Cooperative interaction of Angiopoietin-like proteins 1 and 2 in zebrafish vascular development.

Angiopoietin-like protein (Angptl) 1 and Angptl2, which are considered orphan ligands, are highly homologous, particularly in the fibrinogen-like domain containing the putative receptor binding site. This similarity suggests potentially cooperative functions between the two proteins. In this report, the function of Angptl1 and Angptl2 is analyzed by using morpholino antisense technology in zebrafish. Knockdown of both Angptl1 and Angptl2 produced severe vascular defects due to increased apoptosis of endothelial cells at the sprouting stage. In vitro studies showed that Angptl1 and Angptl2 have antiapoptotic activities through the phosphatidylinositol 3-kinase/Akt pathway, and coinjection of constitutively active Akt/protein kinase B mRNA rescued impaired vascular development seen in double knockdown embryos. These results provide a physiological demonstration of the cooperative interaction of Angptl1 and Angptl2 in endothelial cells through phosphatidylinositol 3-kinase/Akt mediated antiapoptotic activities.

Angiopoietin-Like Protein 1↗

PubMed2005

Expression of cdc25B and cdc25A in medullary thyroid carcinoma: cdc25B expression level predicts a poor prognosis.

Cdc25B and cdc25A phosphatases are prominent stimulators of cell cycle progression and have been suggested to play oncogenic roles. In this study, we immunohistochemically investigated the expression of these phosphatases in medullary thyroid carcinoma. Cdc25B was positive in 35.8% of cases examined. Its positivity was linked only to patient age. However, patients with cdc25B-positive tumors showed a significantly worse disease-free survival rate (P=0.0210) than those with cdc25B-negative tumors. Cdc25A was positive in only 17.2% of cases and was not related to clinicopathological parameters or prognosis. These findings suggest that cdc25B can be regarded as having prognostic significance and as a novel marker of biologically aggressive characteristics in this carcinoma.

Adolescent↗

PubMed2005

Papillary microcarcinomas of the thyroid with preoperatively detectable lymph node metastasis show significantly higher aggressive characteristics on immunohistochemical examination.

OBJECTIVES: We recently demonstrated that papillary microcarcinomas with preoperatively detectable node metastasis in the lateral compartment on ultrasonography (clinically apparent metastasis) show worse postoperative relapse-free survival than those with no metastasis or metastasis that could not be detected preoperatively, but was confirmed by pathological examination after surgery (occult metastasis). In this study, we investigated difference in the aggressive characteristics of microcarcinoma of this type from various perspectives. MATERIALS AND METHODS: We immunohistochemically examined the expression of cell proliferating markers, Ki-67, cyclin D1, p27, and retinoblastoma gene product (pRb), apoptotic markers, single-strand DNA (ssDNA), and metastatic suppressor, kangai-1 (KAI-1) for 19 microcarcinoma patients with clinically apparent metastasis, 14 patents with occult metastasis, and 22 patients without metastasis. RESULTS: Cases of clinically apparent metastasis showed increased cyclin D1 expression together with decreased p27 expression and higher levels of pRb and Ki-67 expression. Furthermore, ssDNA expression was higher and bcl-2 expression was lower in these cases, while KAI-1 expression was significantly reduced. There was no significant difference in the expression of these proteins between cases demonstrating no and occult metastases. CONCLUSION: These findings suggest that cases of clinically apparent metastasis show significantly higher growth based on cell proliferating activity, apoptosis, and expression of metastatic suppressor than those demonstrating no or occult metastases.

Adult↗

PubMed2005

Isolation and expression patterns of genes for three angiopoietin-like proteins, Angptl1, 2 and 6 in zebrafish.

Angiopoietin-like proteins (Angptls) are known to possess biological activities not only in the vascular system, but in the other mammalian tissues; however, their expression patterns and function in embryogenesis have not been extensively characterized. Here, we identify three zebrafish genes (Zangptl1, Zangptl2 and Zangptl6) highly homologous to mammalian Angptl1/ARP1, Angptl2/ARP2 and Angptl6/AGF, and describe their adult and embryonic temporal and spatial expression patterns. Zangptl1 is expressed faintly in the somites, while Zangptl2 is first detected in the yolk sac extension, spinal cord and branchial arches and is later expressed in the liver primordium and pectoral fin buds. Zangptl6 is expressed in the notochord. In addition to its embryonic expression, Zangptl2 is induced in adult fish during fin regeneration.

Angiopoietin-Like Protein 1↗

PubMed2005

Phosphorylation and inactivation of Tob contributes to the progression of papillary carcinoma of the thyroid.

Tob, a member of the Tob/BTG family, is a novel anti-proliferative protein, but it becomes inactive when phosphorylated. In this study, we investigated whether Tob is phosphorylated and inactive in various thyroid neoplasms in order to elucidate how this event plays a role in their progression. Tob phosphorylation was only occasionally seen in normal follicular cells. A high level of Tob phosphorylation was observed in 42.1% of follicular adenoma, 14.3% of follicular carcinoma. In papillary carcinoma, the Tob phosphorylation level was elevated more frequently than that in follicular carcinoma, and 39.7% of specimens were classified in the high group. Tob phosphorylation level in papillary carcinoma was directly linked to tumor size, lymph node metastasis, extrathyroid extension and the presence of poorly differentiated lesion. In anaplastic carcinoma, surprisingly, Tob phosphorylation was not observed in any cases, but the deficiency of Tob expression was also observed in all these cases. These results suggest that (1) Tob phosphorylation contributes to the progression of papillary carcinoma especially in the later phase through cancellation of its anti-proliferative function, and (2) the deficiency of Tob expression is attributable to the lack of Tob phosphorylation in anaplastic carcinoma.

Adenoma↗

PubMed2005

Angiopoietin-related growth factor antagonizes obesity and insulin resistance.

Angiopoietin-related growth factor (AGF), a member of the angiopoietin-like protein (Angptl) family, is secreted predominantly from the liver into the systemic circulation. Here, we show that most (>80%) of the AGF-deficient mice die at about embryonic day 13, whereas the surviving AGF-deficient mice develop marked obesity, lipid accumulation in skeletal muscle and liver, and insulin resistance accompanied by reduced energy expenditure relative to controls. In parallel, mice with targeted activation of AGF show leanness and increased insulin sensitivity resulting from increased energy expenditure. They are also protected from high-fat diet-induced obesity, insulin resistance and nonadipose tissue steatosis. Hepatic overexpression of AGF by adenoviral transduction, which leads to an approximately 2.5-fold increase in serum AGF concentrations, results in a significant (P < 0.01) body weight loss and increases insulin sensitivity in mice fed a high-fat diet. This study establishes AGF as a new hepatocyte-derived circulating factor that counteracts obesity and related insulin resistance.

Angiopoietin-Like Protein 6↗

PubMed2005

Usefulness of thyroglobulin measurement in fine-needle aspiration biopsy specimens for diagnosing cervical lymph node metastasis in patients with papillary thyroid cancer.

The diagnosis of lymph node metastasis in patients with papillary thyroid cancer is an important factor when deciding to perform neck dissection at the initial surgery, as well as for evaluating the lymph node swelling after surgery. Ultrasound (US)-guided fine-needle aspiration biopsy cytology (FNAB-C) is the most useful technique for diagnosing lymph node metastasis. Recently, however, measurement of thyroglobulin in the wash-out of the needle (FNAB-Tg) has been proposed for early detection of neck lymph node metastasis in patients with differentiated thyroid cancer. The purpose of this study was to evaluate the usefulness of FNAB-Tg in detecting lymph node metastasis prior to initial or reoperative thyroid surgery. US-guided FNAB-C was performed on 129 enlarged lymph nodes of 111 patients before surgery. All of them were later histologically confirmed to contain metastasis. Immediately after obtaining an FNAB-C specimen, the needle was rinsed with 0.5 ml of normal saline solution, and the wash-out was subjected to measurement of the Tg level (FNAB-Tg). If the FNAB-Tg level was higher than the serum Tg of the patient, we diagnosed the lymph node as positive (metastatic lymph node). FNAB-Tg sensitivity was 81.4%, and FNAB-C sensitivity was 78.0%. Altogether, 4 (36.4%) of 11 cases judged "benign" and 6 (37.5%) of 16 cases judged "inadequate" by FNAB-C were positive by the FNAB-Tg measurement. Thyroglobulin measurement in fine-needle aspiration biopsy wash-out is thus a useful technique for diagnosing lymph node metastasis of papillary thyroid cancer.

Biopsy, Fine-Needle↗

PubMed2005

Needle tract implantation of papillary thyroid carcinoma after fine-needle aspiration biopsy.

Although fine-needle aspiration biopsy (FNAB) is a useful tool for diagnosing thyroid carcinoma, there are some risks of complications. In this study, we investigated tumor implantation by FNAB of papillary carcinoma. We compared the characteristics of the main tumors and implanted tumors of patients showing FNAB implantations. Between 1990 and 2002, 4912 patients underwent FNAB and were diagnosed as having papillary carcinoma. We encountered 7 cases of needle tract implantation, which account only for 0.14%. We reviewed these 7 cases as well as 3 other patients who underwent FNAB in other hospitals. The intervals between FNAB and detection of the implanted tumor ranged from 2 to 131 months. For these 10 patients, the main tumors in 6 were diagnosed as poorly differentiated carcinoma, and 7 showed extrathyroid extension. Five showed the development of implanted tumor after comparatively shorter intervals (2-68 months), and we classified these as the short interval group. The remaining 5 were classified as the long interval group, because tumor development occurred after 87-131 months. All 5 cases in the short interval group involved preoperatively detectable lymph node metastasis; those in the long interval group did not. The MIB-1 labeling index of the implanted tumor was high in 4 cases in the short interval group, but it was low in all cases in the long interval group. The implanted tumors could be surgically removed without recurrence at the focal sites. These findings indicate that, although high growth activity in the metastatic lesions may be a risk factor of FNAB, inducing the growth of implanted tumors along the needle tract within a short interval after the procedure, FNAB remains the most useful technique for diagnosing thyroid carcinoma. The incidence of implantation was low, and when it did occur, the tumors could be surgically removed without recurrence.

Aged↗

PubMed2005

Stretching exercises to reduce symptoms of postoperative neck discomfort after thyroid surgery: prospective randomized study.

Patients who undergo thyroid surgery frequently suffer from unpleasant symptoms such as a stretching, choking, or pressing feeling or discomfort in the neck for a long time. The usefulness of rehabilitation (i.e., a stretching exercise) for reducing these symptoms after surgery has never been studied. In the present study, attempts were made to evaluate the usefulness of the stretching exercise in reducing disagreeable postoperative symptoms in the patients who had undergone thyroid surgery. A total of 409 patients, including 234 thyroid cancer patients, were randomly divided into a stretching group (n = 204) and a control group (n = 205). Patients in the stretching group were instructed that the stretching exercise was to be performed three times a day beginning the morning following surgery. A questionnaire survey was performed before surgery and then 1 week, 1 month, 6 months, and 1 year after surgery. Total symptom scores obtained from the questionnaire survey from the control group and the stretching group were compared. The use of analgesics was also investigated. Postoperative neck symptoms declined gradually over the course of a year, and the total symptom scores were significantly (p < 0.001) lower in the stretching group than in the control group at all points throughout the year (1 week, 1 month, 6 months, and 1 year). The mean requirement for the use of analgesics during hospitalization was significantly (p < 0.0001) less in the stretching group (1.6 +/- 2.3 tablets, mean +/- SD) than in the control group (3.1 +/- 3.8 tablets). The stretching exercise had effectively reduced postoperative neck symptoms and also reduced the use of analgesics after thyroid surgery.

Adolescent↗

PubMed2005

Ultrasonographically and anatomopathologically detectable node metastases in the lateral compartment as indicators of worse relapse-free survival in patients with papillary thyroid carcinoma.

The recent prevalence of ultrasonography has made it easier to detect lymph node metastasis in the lateral compartment of patients with thyroid carcinoma. In this study, we investigated the prognostic impact of lateral node metastasis preoperatively detectable by ultrasonography (US) and metastasis diagnosed by pathology examination but not detected on preoperative US [anatomopathologically (AP)-detectable metastasis] in 560 patients with papillary carcinoma >1 cm in diameter, who underwent thyroidectomy with modified radical neck dissection at our hospital. Patients with US-detectable metastasis (US+ patients) showed a significantly worse relapse-free survival (RFS) rate than those with no metastasis (US-/AP- patients) or AP-detectable metastasis (US-/AP+ patients) regardless of tumor size. Furthermore, the RFS of US-/AP+ patients with tumors >2 cm was worse than that of US-/AP- patients with tumors >2 cm or US-/AP+ patients with tumors measuring 1.1-2.0 cm. There was no significant difference in RFS between US-/AP+ and US-/AP- patients with tumors measuring 1.1-2.0 cm. These findings suggest that US-detectable lateral metastasis predicts a worse RFS for patients regardless of tumor size, and AP-detectable metastasis affects the RFS of patients with tumors >2 cm.

Adenocarcinoma, Papillary↗

PubMed2005

Ill-defined edge on ultrasonographic examination can be a marker of aggressive characteristic of papillary thyroid microcarcinoma.

We have previously demonstrated that, although most papillary thyroid microcarcinomas (PMC) do not grow or grow only slowly, cases showing lateral node metastasis diagnosed by ultrasonography (US) show an aggressive characteristic associated with poor disease-free survival. In this study, we focused on two prominent U.S. features: tumor, edge definition and strong echoes. We investigated whether these findings reflect aggressive characteristics of PMC in a series of 155 cases. Poor edge definition was observed in 21.5% of patients, all of who showed worse disease-free survival (p = 0.0477) than those with a well-defined edge. Furthermore, this finding was directly linked to US-diagnosed lateral node metastasis (p = 0.0001). Strong echoes were observed in 63.9% of the cases, and fine strong echoes were seen in 25.2%. Cases demonstrating fine strong echoes tended to frequently show recurrence (p = 0.0902), and this finding was also significantly linked to US-diagnosed lateral node metastasis (p = 0.0494). These findings suggest that an ill-defined tumor edge is an important US feature of biologically aggressive PMC. We should carefully follow such patients, regardless of the therapeutic strategy, observation, or surgical treatment chosen.

Adenocarcinoma, Papillary↗

PubMed2005

Favorable surgical results in 433 elderly patients with papillary thyroid cancer.

Papillary thyroid cancer (PTC) has a good prognosis among patients younger than 45 years old, but the prognosis in elder is worse and treatment strategy is not well established. We retrospectively analyzed the clinical features and outcomes of 433 patients with PTC aged 70 years or older. The patients consisted of three groups: group A (n = 327); patients receiving surgical treatment, group B (n = 51); patients with microcancer (maximal diameter, < or = 1.0 cm) who did not undergo surgical treatment, group C (n = 55); patients in whom surgery was contraindicated due to age, high surgical risk or complication by other illnesses. In group A, the mean tumor size was 2.6 +/- 1.5 cm, and 218 patients (66.7%) had pathologically confirmed lymph node metastasis; 110 patients (33.6%) had extrathyroidal invasion. The 5- and 10-year overall survival rates (OSR) in group A were 97.2% and 85%, respectively, which was significantly higher than the 5-year OSR in group C (62.6%). The 5- and 10-year disease-specific survival rates (DSSR) in group A were 98.5% and 91.3%, respectively, which was also significantly higher than the 5-year DSSR in group C (81.8%). Although the patients in group B did not receive any treatment, none of them demonstrated cause-specific death or progression of disease. Papillary thyroid cancer in elderly patients, except for microcancers, may be biologically aggressive. Thus surgery is recommended for these patients, if their general status is judged able to tolerate the stress of anesthesia and surgery.

Aged↗

PubMed2005

Ultrasonography as a method of screening for tracheal invasion by papillary thyroid cancer.

PURPOSE: To assess the reliability of ultrasonography (US) for detecting tracheal invasion by papillary thyroid cancer (PTC). METHODS: We reviewed the clinical and surgical data of 509 patients who underwent surgery for primary PTC during 2003, after routine preoperative US. RESULTS: Ultrasonography showed possible tracheal invasion in 43 of the 509 patients. However, the US findings could not be evaluated in 32 patients because of high tumor calcification, a tumor diameter greater than 4 cm, or tumor extension inferior to the clavicle. We shaved the tracheal wall in 11 patients and resected the tracheal wall in 2 patients. The sensitivity of US for diagnosing of tracheal invasion was 91%, the specificity 93%, the predictive value of a positive test 25%, the predictive value of a negative test 99%, and the accuracy 93%. CONCLUSION: Ultrasonography is a useful method of screening for tracheal invasion. A negative sonogram is a reliable indicator of the absence of tracheal invasion, except when tumors are highly calcified or extend inferior to the clavicle.

Adenocarcinoma, Papillary↗