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T Itoh

Publications and source records attributed to T Itoh.

At least 19 recordsLinked to original sources
PubMed2006

Specific interaction between the initiator protein (Rep) and origin of plasmid ColE2-P9.

The replication initiator protein (Rep) of plasmid ColE2-P9 (ColE2) is multifunctional. We are interested in how Rep binds to the origin (Ori) to perform various functions. We used the wild type and variants of Rep to study the Rep-Ori interaction by both in vitro and in vivo approaches, including biochemical analyses of protein-DNA interactions and an in vivo replication assay. We identified three regions (I, II, and III) of Rep, located in the C-terminal half, and three corresponding binding sites (I, II, and III) in Ori which are important for Rep-Ori interaction. We showed that region I, containing a putative helix-turn-helix motif, is necessary and sufficient for specific Ori recognition, interacting with site I of the origin DNA from the major groove. Region II interacts with site II of the origin DNA, from the adjacent minor groove in the left half of Ori, and region III interacts with site III, next to the template sequence for primer synthesis, which is one and one-half turn apart from site I on the opposite surface of the origin DNA. A putative linker region located between the two DNA binding domains (regions II and III) was identified, which might provide Rep an extended conformation suitable for binding to the two separate sites in Ori. Based on the results presented in this paper, we propose a model for Rep-Ori interaction in which Rep binds to Ori as a monomer.

Amino Acid Sequence↗
PubMed2006

Nasal natural killer/T-cell lymphoma and its association with type "i"/XhoI loss strain Epstein-Barr virus in Chile.

BACKGROUND: Nasal T/natural killer (NK)-cell lymphoma is an aggressive type of non-Hodking's lymphoma associated with Epstein-Barr virus (EBV) and striking geographical variations worldwide. AIM: To characterise nasal NK/T-cell lymphoma associated with genotypes of EBV in Chile, a Latin American country, where multiple strains of EBV, including two new recombinant strains, in healthy individuals were recently found. METHODS: Cases with diagnosis of primary nasal lymphoma were selected for histological and immunohistochemical analysis (CD3, CD3e, CD4, CD8, CD79a, CD56, CD57 and TIA-1) and in-situ hybridisation, serology and genotyping analysis for EBV. RESULTS: Out of 22 cases, 9 (41%) cases fulfilled the World Health Organization criteria for nasal NK/T-cell lymphoma; of these 7 (78%) cases were positive for EBV. Genotyping analysis revealed 6 cases of type 1 EBV and wildtype F at the BamHI-F region, 4 cases type "i" EBV at the BamHI-W1/I1 region; XhoI wild type was found in 2 and XhoI loss in 4 cases, respectively. Cosegregation analysis of the BamHI-W1/I1 region and XhoI restriction site showed the new recombinant strain type "i"/XhoI loss in 3 cases and type "i"/XhoI wild-type strain in 1 case. Most patients were treated with combined anthracycline-containing regimens. Half of the cases attained complete remission. CONCLUSION: Although nasal NK/T-cell lymphomas from Chile share similar clinicopathological features, high association with EBV and unfavourable prognosis with those described elsewhere, genotype analysis shows that the new recombinant type "i"/XhoI loss strain might contribute to explain the intermediate incidence of nasal NK/T-cell lymphomas in Latin America.

Adult↗
PubMed2006

Concurrent infiltration by CD8+ T cells and CD4+ T cells is a favourable prognostic factor in non-small-cell lung carcinoma.

The purpose of this study was to clarify the relationship between the number of tumour-infiltrating T lymphocytes and the clinicopathological features and clinical outcome in patients with non-small-cell lung cancer (NSCLC). Tissue specimens from 109 patients who underwent surgical resection for NSCLC were immunohistochemically analysed for CD4 and CD8 expression. Patients were classified into two groups according to whether their tumours exhibited a 'high' or 'low' level of CD8(+) or CD4(+) lymphocyte infiltration. Although the level of infiltration by CD8(+) T cells alone had no prognostic significance, the survival rate for patients with both 'high' CD8(+) and 'high' CD4(+) T-cell infiltration was significantly higher than that for the other groups (log-rank test, P=0.006). Multivariate analysis indicated that concomitant high CD8(+) and high CD4(+) T-cell infiltration was an independent favourable prognostic factor (P=0.0092). In conclusion, the presence of high levels of both CD8(+) T cells and CD4(+) T cells is a significant indicator of a better prognosis for patients with NSCLC, and cooperation between these cell populations may allow a significantly more potent antitumour response than either population alone.

Adult↗
PubMed2006

Management of childhood and adolescent thyroid carcinoma: long-term follow-up and clinical characteristics.

AIM: This analysis was performed to evaluate clinical factors such as local tumor control, control of distant metastasis, survival, and complications in children and adolescents with thyroid carcinoma. MATERIALS AND METHODS: From 1960 to 2003, 21 children and adolescents (16 girls and 5 boys, aged 4 to 15 years) were treated for thyroid carcinoma in our departments. Clinical data, operative findings, pathological findings, operative procedures, intra- and postoperative complications and follow-up were evaluated. Follow-up of patients ranged from 3 to 42 years (median, 20 years). RESULTS: Papillary carcinoma was found in 20 patients (95%) and follicular carcinoma in one patient. Cervical lymph node metastases were found in 12 out of 21 patients (57.1%) when thyroid carcinoma was diagnosed, and 5 patients (23.8%) had pulmonary metastasis. In patients with pulmonary metastasis, total thyroidectomy and bilateral radical lymph node resection was performed in 3 patients, lobectomy of the thyroid and radical lymph node resection in one patient, and partial thyroidectomy in one patient. All three patients who underwent total thyroidectomy are still alive. Internal irradiation by 131I and thyroid hormone replacement therapy was administered to 2 of 3 patients with pulmonary metastasis. CONCLUSION: Despite metastasis in the lymph nodes and even the lungs, the prognosis for patients with papillary carcinoma is good. Total thyroidectomy and positive 131I therapy are recommended for childhood and adolescent thyroid carcinoma with pulmonary metastasis.

Adenocarcinoma, Follicular↗
PubMed2006

Histological differentiation between prenatally diagnosed choledochal cyst and type I cystic biliary atresia using liver biopsy specimens.

Because it is difficult to distinguish preoperatively between prenatally diagnosed choledochal cyst (CC) and type I cystic biliary atresia (BA) by ultrasound scanning or magnetic resonance imaging (MRI), some modality of discrimination for the 2 entities is required. The aim of this study was to investigate the histological differences between prenatally diagnosed CC and type I cystic BA using liver biopsy specimens. Four children with prenatally diagnosed CC and two children with prenatally diagnosed type I cystic BA were identified by fetal ultrasonography between 1985 and 2003. The control group included two children who were operated on at an earlier period due to postnatally diagnosed BA. Liver wedge biopsy in the right lobe was performed at the time of the radical operation. Histological findings of the H & E-stained liver biopsy specimens were classified into 4 grades (Grade 0, no abnormality; Grade 1, ductular proliferation without bridging fibrosis; Grade 2, ductular proliferation with bridging fibrosis; and Grade 3, liver cirrhosis). The CC group consisted of one case of Grade 0 and three cases of Grade 1. The type I cystic BA group consisted of one case each of Grade 2 and Grade 3. In the control group, both cases were Grade 2. The authors suggest that exploratory laparotomy might be avoided and, instead, histologic examination using liver biopsy specimens can be a reliable test for the differential diagnosis of CC and type I cystic BA in prenatally diagnosed neonates.

Biliary Atresia↗
PubMed2006

Management and algorithm for focal nodular hyperplasia of the liver in children.

PURPOSE: The aim of this study was to determine an appropriate management plan for childhood and adolescent FNH, in particular to establish an algorithm for preoperative diagnosis and treatment. PATIENTS AND METHODS: Between 1985 and 2003, 4 children with FNH were diagnosed. Of these 4 patients, 3 (Group A) underwent tumor resection, and 1 (Group B) was treated by conservative management. Clinical data, pathological findings and follow-up were evaluated retrospectively. RESULTS: The 3 patients in Group A were symptomatic, while the 1 patient in Group B was asymptomatic. In 3 of 4 patients, a homogeneous tumor with a central stellate area was noted on abdominal ultrasonography, CT scan and MR imaging. In case 2, SPIO-enhanced MR imaging was useful for differentiating FNH from hepatocellular carcinoma. Though percutaneous needle biopsy was performed in case 3, a pathologically definitive diagnosis was impossible. An open biopsy was performed in case 4 and FNH was diagnosed. In case 4 treated by conservative management, the tumor size did not change during the 7 years after the diagnosis of FNH. CONCLUSION: FNH is usually treated conservatively because of the good evolutionary outcome of the lesion. Surgery is indicated in cases of complications, compressed adjacent organs, lesion progression, or for symptomatic patients. We advocate the use of less invasive SPIO-enhanced MR imaging instead of open biopsy when the diagnosis of focal liver lesions is not clear after contrast-enhanced CT scan and non-enhanced MR imaging.

Adolescent↗
PubMed2006

Alteration of T-cell receptor repertoires during thymic T-cell development.

The majority of thymocytes die in the thymus, whereas small populations of T cells that are able to specifically recognize an antigen are considered to survive. Although the thymic selection is thought to have a profound effect on T-cell receptor (TCR) repertoire, little is known how TCR repertoire is formed during the thymocyte developmental process. We examined TCRalpha- and beta-chain variable regions (TCRAV and TCRBV) repertoire in thymic T-cell subpopulations from mice bearing different major histocompatibility (MHC) haplotypes. In Balb/c mice, but not C57BL/6, remarkable alterations of the TCR repertoire were observed in mature T-cell subpopulations as previously reported. In contrast, there were no significant differences of TCRBV repertoire between DN3 (CD25(+)CD44(-)) and DN4 (CD25(-)CD44(-)), and between DN4 and DP. These results suggest that (1) TCR repertoire of mature T cells was formed mainly under the influence of endogenous superantigens, while MHC haplotypes played the least role; (2) the 'beta-selection' process during immature stages had little impact on TCRBV repertoire formation; and (3) TCR repertoire in immature T-cell subpopulations was extremely similar between different strains of mice. We thus consider that pre-selection TCR repertoire in immature T cells could be determined by some genetic factors conserved among different strains.

Animals↗
PubMed2006

Immunohistochemical analysis of nuclear survivin expression in esophageal squamous cell carcinoma.

Despite advances in the treatment of esophageal carcinoma, the prognosis for this disease remains poor. Therefore, it is important to obtain a better understanding of the molecular basis of esophageal carcinogenesis. The purpose of this study was to clarify the roles of survivin in esophageal squamous cell carcinoma (ESCC). One hundred 22 ESCC surgical specimens resected from 1989 to 1999 were examined. Survivin expression was assessed by immunohistochemistry. Tumor cells were considered survivin-positive if the immunoreactivity was confined to the nucleus, and a scoring method was applied. Survivin-positive immunostaining was detected in 68 patients (56%). There was a significant association between survivin expression and pN (P = 0.0472). Moreover, the overall survival rate was worse in patients with survivin-positive tumors than in patients with survivin-negative tumors (P = 0.0189). The overexpression of survivin was associated with the overall survival rate and poor prognosis in patients with ESCC. Survivin may be targeted during cancer therapy because of its selective expression in malignant tissue.

Aged↗
PubMed2006

[Small peripheral lung cancer incidentally detected by massive hemoptysis].

A 47-year-old man was admitted to our hospital for treatment of massive hemoptysis. He was intubated and underwent bronchial arterial embolization because of this deteriorating respiratory state and uncontrollable hemoptysis. Computed tomography (CT) of the chest showed a 1-cm nodular shadow in the peripheral apical lobe (S1) of the right lung. He underwent right upper lobectomy for the purpose of preventing re-hemorrhage as well as making the definitive diagnosis of nodular shadow in S1 of the right lung. Intraoperative pathological examination revealed the nodule as adenocarcinoma, and mediastinal lymphadenectomy was added to the right upper lobectomy. The patient recovered uneventfully, and there has been no sign of recurrence for 15 months after the operation.

Adenocarcinoma↗
PubMed2006

[Metastatic lung tumor from uterine leiomyosarcoma].

We herein present 2 cases of metastatic lung tumor derived from uterine leiomyosarcoma. In the case 1, a 59-year-old woman was admitted to our hospital to examine abnormal shadow detected on chest X-ray. She had undergone hysterectomy and oophorectomy for uterine leiomyosarcoma 19 months previously. A round 3 cm mass in the right lung (S10) was seen on chest X-ray and computed tomography (CT). No other distant metastases or local recurrence were found, and the right lower lobectomy was perfomed under the clinical diagnosis of metastatic lung tumor. Postoperative pathologic examination revealed the tumor as a metastatic leiomyosarcoma. The patient recovered uneventfully, and there have been no signs of recurrence for 26 months after the pulmonary resection. In the case 2, a 58-year-old woman, who had undergone hysterectomy and oophorectomy for uterine leiomyosarcoma 7 months previously, was admitted to our hospital for further examination of pulmonary tumors on chest X-ray. Two tumors were recognized in the left lung (S8 and S10) on chest X-ray and CT. No other distant metastases or local recurrence were found, and the left lower lobectomy was performed under the clinical diagnosis of metastatic lung tumors. Pathological examinations revealed smooth muscle cells with nuclear pleomorphism and high mitotic indices. The tumors proved to be lung metastases derived from uterine leiomyosarcoma. Postoperative course was uneventful. However, brain metastasis was found 1 month after the pulmonary resection, and she underwent resection of brain metastasis. Two months after the brain metastasectomy, local recurrence of the brain tumor developed and re-resection followed by stereotactic radiotherapy was performed. Furthermore, intrapelvic recurrence was found 4 months after the pulmonary resection. Exploratory laparotomy revealed the tumor was unresectable, and she received 4 courses of chemotherapy (paclitaxel and carboplatin). For metastatic lung tumor from uterine leiomyosarcoma, surgery has been considered the best choice. However, for patients with uterine leiomyosarcoma who cannot be treated surgically because of multiple metastatic tumors or poor surgical risk chemotherapy (paclitaxel and carboplatin) or stereotactic radiotherapy can be strategies.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2005

Limited VH gene usage in B-cell clones established with nurse-like cells from patients with rheumatoid arthritis.

OBJECTIVES: Nurse-like stromal cells (NLC) in synovia and bone marrow of patients with rheumatoid arthritis (RA) can support pseudoemperipolesis, protect from apoptosis and enhance immunoglobulin production of peripheral blood B cells isolated from healthy individuals, suggesting the profound contribution of hyperactivation of B cells in RA. In the course of establishing RA-NLC from RA patients, we observed the growth of B cells in the presence of RA-NLC. METHODS: We cloned B cells from the synovium or bone marrow of RA patients using the limiting dilution technique. For established clones, nucleotide sequences of immunoglobulin and surface antigens were investigated. To investigate the dependence of these clones on NLC, differences in the proliferation and the amount of immunoglobulin produced in the presence or absence of NLC were compared. Immunocytochemical staining of various cells was performed using the antibody these clones produced. RESULTS: Nine B-cell clones established from RA patients showed RA-NLC-dependent growth. These B-cell clones expressed CD19, CD20, CD38, CD39 and CD40, suggesting that the cloned cells were mature and activated. All clones secreted immunoglobulins in culture media, which were specific for intracellular components of various cell lines, including RA-NLC. Interestingly, we found limited usage of immunoglobulin heavy-chain variable regions (VH) among B-cell clones from RA patients. These repertoires were reported to be detected preferentially in fetal livers. CONCLUSION: The present study provides a novel insight into the involvement of RA-NLC in the immunopathogenesis of RA via an autoreactive B cell development and/or activation mechanism.

Antigens, CD↗
PubMed2005

Bleeding disorder as the first symptom of biliary atresia.

Biliary atresia (BA) is occasionally diagnosed in infants whose first symptom is a bleeding disorder, such as intracranial bleeding, nasal bleeding or gastrointestinal bleeding. The authors describe 3 cases in which a bleeding disorder was the first symptom of BA. The presenting symptom was intracranial bleeding in a male on day 55 after birth, nasal bleeding in a female at 65 days, and gastrointestinal bleeding in a female at 25 days. Coagulation studies revealed a vitamin K deficiency in all patients. After the administration of vitamin K, the results of coagulation tests normalized and the bleeding tendency of the infants ceased. Subsequently, BA was suspected to be the cause of these bleeding disorders based on imaging findings. BA should therefore be considered in all infants with sudden onset of a tendency to bleed.

Biliary Atresia↗
PubMed2005

Cyclin D1, E2F1 expression levels are associated with characteristics and prognosis of esophageal squamous cell carcinoma.

SUMMARY. We performed a multi-institutional analysis of E2F1 and cyclin D1 expression in cases of esophageal squamous cell carcinoma (ESCC). Cyclin D1 and E2F1 are involved in the transition of cell cycle phases and associated with tumor progression. However, no previous studies have concurrently analyzed combined E2F1 and cyclin D1 expression. The purpose of this study was to clarify the relationship of E2F1 and cyclin D1 in ESCC. We studied 122 patients with primary ESCC who underwent surgical tumor resection. Immunohistochemical analyses were performed for E2F1 and cyclin D1. A statistical analysis of immunohistochemistry results, clinicopathological features, and prognosis was performed. E2F1/cyclin D1 (-/-) tumors were present in 31 patients (25.4%) and correlated with reduced tumor progression. In these patients, pT (P=0.0001), pN (P<0.0001), p-Stage (P=0.0019), and survival rates were better than in patients who were positive for either E2F1 or cyclin D1 (P=0.0232). The expression of E2F1 and cyclin D1 is an indicator of tumor progression and prognosis in patients with ESCC. Combined analysis of E2F1 and cyclin D1 expression helps to determine the characteristics and prognosis of ESCC.

Adult↗
PubMed2005

Root fracture in immature anterior teeth followed for 15 years.

We report a case of injury to an immature tooth, observed over a period of 15 years. In 1987, a 9-year-old boy fell down in a schoolyard. The right central incisor demonstrated palato-version and radiographic observations revealed that the roots of both central incisors were incomplete. Further, a root fracture in the apical region of the central incisors was observed. During the first treatment visit, the right central incisor was repositioned and both teeth splinted. After confirming that the line of fracture was aligned, the fixation was continued for 2 months. The teeth were examined periodically for the next 15 years. Both teeth had favorable outcomes with continued root development of both the apical and coronal segments with good apposition of the fracture lines.

Child↗
PubMed2005

A case of canine apocrine sweat gland adenoma, clear cell variant.

A cutaneous mass at the base of the retroauricular region of a 4-year-old, female Golden Retriever was examined pathologically. Histologically, the mass formed multiple nodules consisting of a proliferation of large clear cells with abundant cytoplasm. Mitotic figures among the neoplastic cells were very sparse. The large clear cells were intensely positive for cytokeratins (AE1/AE4, cytokeratin 8 and 18) and moderately positive for lysozyme and contained periodic acid-Schiff-positive granules in the cytoplasm. In addition, small flat cells lined the islands of neoplastic large clear cells, and these were strongly positive for alpha-smooth muscle actin and vimentin, and some were positive for cytokeratin (AE1/AE4), suggesting they were myoepithelial cells. No local recurrence or metastasis has been recognized during the 18 months since surgical excision. On the basis of these findings, the present tumor was diagnosed as apocrine sweat gland adenoma, clear cell variant. There have been few previous reports of canine apocrine adenomas showing a clear cell morphology.

Adenoma, Sweat Gland↗
PubMed2005

Epstein-Barr virus-associated gastric carcinoma in Lima, Peru.

We examined 254 gastric carcinomas (GCs) diagnosed in four hospitals in Lima, Peru, and its suburban area during the period between 1994-2001. Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) was identified by the in situ hybridization (ISH) technique to detect EBV-encoded small RNA (EBER) in gastric tissue. EBVaGCs, where EBER ISH staining was observed in all carcinoma cells, accounted for 3.9% (10/254) of gastric adenocarcinomas, the lowest frequency ever reported in Latin American countries. EBVaGC incidence rates in Peru, which we estimated on the basis of the present study and cancer incidence in Lima, were 0.8 per 100,000 among men and 0.5 per 100,000 among women. These estimates are much lower than those reported in our previous studies in Colombia (4.1 and 1.4 per 100,000 among men and women, respectively), a neighboring country, and in Japan (6.4 and 1.1 per 100,000 among men among women, respectively). Interestingly, EBVaGC in Peru showed no evident male predominance, as opposed to the findings reported in a majority of studies. Other clinicopathological features of EBVaGC in Peru were similar to those found in literature: EBVaGC showed no age dependence, a predominance in the non-antrum part of the stomach, and high frequencies in histological subtypes of moderately differentiated tubular adenocarcinoma and solid poorly differentiated adenocarcinoma. There was a case of well-differentiated adenocarcinoma showing a partial EBER-1-positive staining. In this carcinoma, the tumor in the body (middle third of the stomach) was EBER-1 positive but the tumor in the stomach antrum showed no noticeable EBER-1 ISH staining. We suspect this was a case of synchronous double carcinomas. Further studies are needed to identify the cause of the low frequency and lack of male predominance of EBVaGC in Peru.

Aged↗