Biomedical subjects

A Ochiai

Publications and source records attributed to A Ochiai.

At least 19 recordsLinked to original sources

PubMed2006

Impact of isolated tumor cells in sentinel lymph nodes detected by immunohistochemical staining.

AIM: Isolated tumor cells (ITCs) in lymph nodes are defined histologically as node-negative. The clinical impact of ITCs in sentinel lymph nodes (SLNs) remains unclear. We report the prognosis of breast cancer patients with ITC-positive SLNs detected by immunohistochemical staining. PATIENTS AND METHODS: One hundred and sixty-five breast cancer patients with histologically negative SLNs were seen between January 1998 and December 2000. In 69 patients, sentinel node biopsy (SNB) was immediately followed by axillary lymph node dissection, and 96 had undergone SNB alone. Permanent sections of 301 SLNs were re-examined after hematoxylin-eosin staining and cytokeratin 19 immunohistochemical staining. RESULTS: ITCs were found in 18 SLNs of 17 patients and a micrometastasis was found in one SLN of one patient. As of November 2005, only one patient with ITCs in one SLN had supraclavicular lymph node recurrence. In contrast, 18 of the 147 patients with negative SLNs had tumor recurrence. Surgical management of the axilla had no influence on recurrence-free survival in all of the patients. CONCLUSION: This study shows that breast cancer patients with ITC-positive SLNs should be clinically managed as node-negative patients.

Adult↗

PubMed2006

Immunohistochemical prognostic factors in resected colorectal lung metastases using tissue microarray analysis.

AIMS: Immunohistochemical prognostic factors of pulmonary metastatic colorectal cancer lesions have not been well investigated. The study was conducted to identify the immunohistochemical prognostic factors of metastasized colorectal cancer. METHODS: We immunohistochemically investigated the expression of insulin-like growth factor-1 receptor (IGF1-R), E-cadherin, beta-catenin, and p53 using a tissue microarray in the surgical specimens of 86 metastatic lesions. RESULTS: The univariate analysis revealed E-cadherin and membrane beta-catenin positive to be prognostic factors. IGF1-R and p53 were not significantly associated with the patient's survival. In multivariate analysis, the reduced expression of E-cadherin, aerogenous spread with floating cancer cell clusters and vascular invasion were independent prognostic factors. CONCLUSIONS: The reduced expression of E-cadherin in the pulmonary metastatic lesions was an independent predictor of poor survival after pulmonary metastasectomy.

Biomarkers, Tumor↗

PubMed2006

Do motorcyclists have erectile dysfunction? A preliminary study.

The aim of the present study was to evaluate the relationship between motorcycling and erectile dysfunction (ED). We investigated the relationship between motorcycling and erectile function using the 5-items version of the International Index of Erectile Function (IIEF5) in 234 motorcyclists (response rate 75%) and 752 healthy controls (response rate 66%). In all, 161 (69%) of 234 motorcyclists were diagnosed as ED based on IIEF5. The prevalence of ED in the motorcycle group increased by age as: 58, 63, 76 and 93%, for motorcyclists in 20-29, 30-39, 40-49 and 50-59 years, respectively. There was a significant difference in the prevalence of ED between the motorcycle group and the control group in all age groups. On stepwise logistic regression analysis, motorcycling was the strongest risk factor for ED. Although the severity of ED in motorcyclists was not so severe, motorcycling may be one of risk factors for ED.

Adult↗

PubMed2006

Comparison of the immunophenotypes of signet-ring cell carcinoma, solid adenocarcinoma with mucin production, and mucinous bronchioloalveolar carcinoma of the lung characterized by the presence of cytoplasmic mucin.

The latest World Health Organization (WHO) classification divides adenocarcinoma mainly into adenocarcinoma mixed subtypes, acinar adenocarcinoma, papillary adenocarcinoma, bronchioloalveolar carcinoma, and solid adenocarcinoma with mucin production, and it mentions several variants, including fetal adenocarcinoma, mucinous ("colloid") adenocarcinoma, mucinous cystadenocarcinoma, signet-ring adenocarcinoma, and clear cell adenocarcinoma. In general, the mucin-producing adenocarcinoma of the lung comprises signet-ring cell carcinoma (SRCC), solid adenocarcinoma with mucin production (SA), and mucinous bronchioloalveolar carcinoma (m-BAC), mucinous ("colloid") adenocarcinomas and/or mucinous cystadenocarcinoma, and mucoepidermoid carcinoma. As SRCC, SA, and m-BAC exhibit distinct clinical features, it is important to identify differences in their immunohistochemical characteristics to better understand their histogenesis. In this study we analysed SRCC, SA, m-BAC, normal lung, and foregut-related secretory tissue for immunohistochemical differences using tissue microarrays. SRCC and SA showed high expression of MUC1 (97.4% and 100%, respectively), cytokeratin (CK) 7 (both 100%), and thyroid transcription factor-1 (TTF-1) (81.1% and 100%, respectively). They also showed low expression of MUC5AC (25.5% and 21.1%, respectively) and MUC6 (18.3% and 10.5%, respectively), whereas m-BAC showed high expression of MUC5AC (97.5%), MUC6 (75.0%), and CK7 (94.7%), but low expression of MUC1 (57.5%), and TTF-1 (27.5%). Hierarchical clustering showed that the immunophenotypes of SRCC and SA belong to the same category as alveolar lining cells, whereas m-BAC clustered onto another branch with gastric foveolar cells and bronchial goblet cells. These immunohistochemical findings support the results of our previous clinicopathological analysis of SRCC of the lung showing that SRCC occurs anatomically in the peripheral portion of the lung rather than in the bronchial gland-bearing portion.

Adenocarcinoma↗

PubMed2005

Predictors of tumour involvement in remaining axillary lymph nodes of breast cancer patients with positive sentinel lymph node.

AIMS: To characterize the various clinicopathologic features in cases of breast cancer with positive sentinel lymph nodes (SLNs), in order to determine factors that might help in predicting the involvement of the non-SLNs. METHODS: A retrospective database review was performed of 726 breast cancer patients with stage 0-II, in whom SLNs were successfully identified. One hundred eighty-five of these patients showed positive SLNs, and subsequently underwent axillary lymph node dissection (ALND). These cases were divided into two groups based on the presence or absence of metastases in the non-SLNs, i.e. positive non-SLNs (NSLN+; 81 cases) and negative non-SLNs (NSLN-; 104 cases). RESULTS: Multivariate analysis revealed that a larger size of the primary tumour (>2.0cm), presence of lymphatic invasion, larger size of the largest SLN metastasis (>2mm), and a 100% metastatic rate in the SLNs (number of positive SLNs/number of harvested SLNs) were significantly associated with NSLN+. Among the cases in which all the four factors were present, 73% (30/41) were found to have NSLN+. CONCLUSION: We found four independent predictors in relation to non-SLN metastasis. Although these factors might be useful for determining the need of additional ALND, it would seem that even the presence of all of these four factors in combination may be insufficient to safely omit ALND. Thus, until further evidence is accumulated from the results of large clinical trials, ALND would still be recommended for patients with SLN metastasis.

Axilla↗

PubMed2005

Primary tumour-vessel tumour-nodal tumour classification for patients with invasive ductal carcinoma of the breast.

There are many studies that show biological differences between invasive ductal carcinoma (IDC) with and without nodal metastasis, but no prognostic classification taking into consideration any biological differences between them is currently available. We previously investigated the histological characteristics that play an important role in tumour progression of IDCs according to their nodal status, and a new prognostic histological classification, the primary tumour-vessel tumour-nodal tumour (PVN) classification, was devised based on the histological characteristics of IDCs with and without nodal metastasis. Multivariate analyses using the Cox proportional hazard regression models were used to compare the ability of the PVN classification to predict tumour recurrence and death in 393 IDC patients based on the following histological classifications: (1) the pTNM classification, (2) the Nottingham Prognostic Index, (3) the modified Nottingham Prognostic Index, and (4) the histologic grade. In IDCs without nodal metastasis, only the PVN classification significantly increased the hazard rates (HRs) of tumour recurrence and death (P<0.05), independent of the hormone receptor status. Similarly, in IDCs with nodal metastases, only the PVN classification significantly increased the HRs of tumour recurrence and death (P<0.05), independent of the hormone receptor status. We conclude that the PVN prognostic histological classification is the best classification available for IDC of the breast.

Breast Neoplasms↗

PubMed2005

Overexpression of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-4 in the human breast and colon malignant tumors.

6-Phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB) is a bifunctional enzyme, which is responsible for maintaining the cellular level of fructose-2,6-bisphosphate, a powerful allosteric activator of glycolysis. We describe herein the overexpression of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-4 (PFKFB-4) isozyme in the human breast and colon malignant tumors as compared to corresponding non-malignant tissue counterparts. We have shown also that breast malignant cell line MCF7 constitutively express PFKFB-4 mRNA and that the expression of this gene is highly induced by hypoxia. Overexpression of PFKFB-4 transcript levels in breast and colon malignant tumors correlates with enhanced expression of PFKFB-3, hypoxia-inducible factor (HIF)-1alpha and known HIF-1 dependent genes glucose transporter 1 (Glut1) and vascular endothelial growth factor (VEGF). Thus, our data clearly demonstrates overexpression of PFKFB-4 mRNA and protein in the breast and colon malignant tumors.

Breast↗

PubMed2005

Multicolour digital image analysis system for identification of bacteria and concurrent assessment of their respiratory activity.

AIMS: To develop a rapid and simple multicolour digital image analysis system for simultaneous identification of bacteria and assessment of their metabolic activity. METHODS AND RESULTS: We developed an image analyser capable of distinguishing triple-stained bacterial cells. Bacteria were stained with a nucleic acid stain, a fluorescent antibody and a fluorescent metabolic indicator for enumeration, species identification and assessment of metabolic activity. This multicolour image analyser was used to simultaneously identify Escherichia coli O157:H7 in milk samples and assess their respiratory activity. The images of the triple-stained bacteria were captured using a combination of blue light and u.v. excitation and an epifluorescence microscope and were processed by our image analyser. We found a good correlation between the counts of actively respiring (r = 0.93) and total (r = 0.94) E. coli O157:H7 measured by digital image analysis and visual observation. CONCLUSION: The multicolour digital image analysis system described here was able to quantify active pathogenic micro-organisms within 2 h. SIGNIFICANCE AND IMPACT OF THE STUDY: This multicolour image analysis allows the rapid and simultaneous quantification of bacteria, identification of species and assessment of metabolic activity.

Animals↗

PubMed2004

Overexpression of TGF-beta by infiltrated granulocytes correlates with the expression of collagen mRNA in pancreatic cancer.

Pancreatic cancer is often associated with an intense production of interstitial collagens, known as the desmoplastic reaction. To understand more about desmoplasia in pancreatic cancer, the expression of mRNA for type I and III collagens and potent desmoplastic inducing growth factors transforming growth factor-beta (TGF-beta), connective tissue growth factor (CTGF), acidic and basic fibroblast growth factor (FGF), platelet-derived growth factor (PDGF) A and C and epidermal growth factor (EGF) was analysed by quantitative RT-PCR. Expression of both collagens in 23 frozen primary pancreatic cancer nodules was significantly higher than that in 15 non-neoplastic pancreatic tissues. The expressions of mRNAs for TGF-beta, acidic FGF, basic FGF and PDGF C were likewise higher in surgical cancer nodules, while that of CTGF, PDGF A and EGF were not. Among these growth factors, the expression of TGF-beta mRNA showed the most significant correlation with that of collagens (P<0.0001). By immunohistochemistry, TGF-beta showed faint cytoplasmic staining in cancer cells. In contrast, isolated cells, mainly located on the invasive front surrounding cancerous nests, were prominently and strongly stained. These TGF-beta-positive cells contained a segmented nucleus, were negative for anti-macrophage (CD68) and positive for anti-granulocyte antibodies, indicating their granulocytic nature. In conclusion, TGF-beta seemed to play a major role among the various growth factors in characteristic overproduction of collagens in pancreatic cancer. Moreover, the predominant cells that express TGF-beta were likely to be infiltrated granulocytes (mostly are neutrophils) and not pancreatic cancer cells.

Adenocarcinoma↗

PubMed2004

de Haas-van Alphen effect in ZrZn2 under pressure: crossover between two magnetic states.

We report measurements of the de Haas-van Alphen effect in ZrZn2 under hydrostatic pressures up to 21 kbar where the Curie temperature vanishes. The exchange splitting of a Fermi surface changes in behavior with increasing magnetic field, which is qualitatively consistent with the behavior of the high-field magnetization, suggesting the existence of a crossover between two distinct magnetic states. These and previously unexplained findings may be understood in terms of a p-T-B phase diagram qualitatively similar to that of the ferromagnetic superconductor UGe2.

Journal Article↗

PubMed2002

Sentinel node biopsy for breast cancer patients in Japan.

Sentinel node biopsy may become a standard procedure to detect lymph node metastases in early breast cancer. Numerous studies have confirmed and demonstrated the reliability of the hypothesis of sentinel node biopsy, with a high identification rate and overall accuracy connected with dye-guided and radio-guided sentinel node biopsy. To assess the benefit of sentinel node biopsy, randomized clinical trials are underway in Western countries comparing sentinel node biopsy with conventional axillary lymph node dissection. In Japan, feasibility studies on sentinel node biopsy started in the mid-1990s. The dye and radiopharmaceuticals associated with sentinel node biopsy commonly used in Western countries are not available in Japan. Japanese investigators have attempted to perform sentinel node biopsy using other dyes and radiopharmaceuticals. The results from feasibility studies have been similar to those reported previously. In conclusion, sentinel node biopsy for breast cancer patients is successful in Japan. The current status and the problems are discussed.

Breast Neoplasms↗

PubMed2002

Significant decrease of the International Index of Erectile Function in male renal failure patients treated with hemodialysis.

In order to evaluate the erectile function in male renal failure patients treated with hemodialysis (HD), we investigated the International Index of Erectile Function (IIEF) in patients and healthy controls. The subjects were 174 male patients treated with HD, of whom 43 had diabetes mellitus (DM) and the remaining 131 patients did not have DM. The controls were 1133 healthy males. We evaluated the prevalence of erectile dysfunction (ED) using the erectile function (EF) score, which is one of the five domains of the IIEF, in each age group (upto 39 y old, 40-49 y old, 50-59 y old, 60-69 y old). The severity of ED was classified into five categories using EF in each age group. The univariate logistic regression analysis and multiple variate analysis of IIEF in HD patients were performed. The prevalence of ED in HD patients was significantly higher than that in the controls in each age group. The severity of ED in HD patients was also significantly higher than that in the controls in each age group. In the logistic regression analysis and multiple variate analysis of IIEF in HD patients, DM and age were significant risk factors on sexual dysfunction. ED was more prevalent in male renal failure patients treated with HD than in the controls. In the patient group, ED was more prevalent in older DM patients.

Adult↗

PubMed2002

Erythrocyte aldose reductase correlates with erectile dysfunction in diabetic patients.

Erectile dysfunction (ED) is a common complication of diabetes mellitus. Erythrocyte aldose reductase (AR) has been implicated in a variety of diabetic complications. The subjects were 62 diabetic patients, of whom 25 were treated with hemodialysis (chronic renal failure CRF group) and the remaining 37 did not have chronic renal failure (DM group). The controls were 20 healthy volunteers age-matched to the patients. The level of AR was measured by the quantitative determination kit for AR in all patients and controls. In this study, ED was diagnosed by 5-item version of the International Index of Erectile Function (IIEF-5). The average level of AR in the CRF group was significantly higher than that in the DM group and controls (P<0.001). The average level of AR in the DM group without ED was significantly lower than that in the DM group with ED and controls (P<0.005). These results suggest that the level of AR may be a useful modality for prediction of ED in diabetic patients.

Aged↗

PubMed2001

Prostate-specific antigen induces osteoplastic changes by an autonomous mechanism.

The high prevalence of osteoplastic bone metastasis in prostate cancer (PC) is believed to be attributable to the production of osteoblast-stimulating factors by PC cells. Prostate-specific antigen (PSA) is a serine protease and an important serological marker for PC. Exposure of osteoblasts to PSA in vitro was found to result in cell proliferation and marked upregulation of transforming growth factor-beta (TGF-beta) mRNA expression. This PSA-induced increase in osteoblast proliferation was inhibited by anti-TGF-beta antibodies and serine protease inhibitors. In vivo, PSA markedly enhanced osteoplastic changes in human adult bone implanted into NOD/SCID mice without PC cells, and alpha(1)-antichymotrypsin prevented the PSA-induced increase in bone volume. PSA promotes osteoplastic change by activating an osteoblast autonomous mechanism that is independent of the production of bone growth factors by PC cells.

Aged↗

PubMed2001

Accumulation of losses of heterozygosity and multistep carcinogenesis in pulmonary adenocarcinoma.

Sixty-six replacing growth-type early lung adenocarcinomas, measuring 2 cm or less across their greatest dimension, were used to investigate allelic losses at eight loci on the eight chromosomes carrying the principal cancer-associated genes. In total, 2 (16.7%) of 12 type A tumors (localized bronchioloalveolar carcinoma, LBAC) and 11 (39.3%) of 28 type B tumors (LBAC with alveolar collapse), which correspond to early lung adenocarcinomas including cancers in situ, showed allelic losses in one or more of the regions examined. In contrast, 25 (96.2%) of 26 type C tumors (LBAC with active fibroblastic proliferation), which correspond to small but advanced tumors, showed allelic losses in one or more regions. The change in histology from type A to type C was characterized by a significant rise in the incidence of allelic losses (P < 0.01). Deletions of 3p, 17p, 18q, and 22q increased significantly during malignant progression. In type C tumors that showed heterogeneous histological features, the tumor cells in the central fibrotic areas exhibited more allelic losses than those in the peripheral bronchioloalveolar growths and were, therefore, considered to have progressed to a more advanced stage than the tumor cells in the peripheral regions.

Adenocarcinoma, Bronchiolo-Alveolar↗

PubMed2001

Clinicopathological significance of tumor nest configuration in patients with esophageal squamous cell carcinoma.

BACKGROUND: Cancer-stromal interactions are an important mediator of cancer invasion and metastasis. METHODS: The authors investigated the clinicopathological significance of tumor nest configuration and the surrounding stroma in 159 patients with advanced esophageal squamous cell carcinoma (ESCC). The tumors were classified microscopically into two types. Type A tumors had oval-shaped or sheet-like tumor nests (with > 80% of the tumor area showing these features). Type B tumors had asteroid-shaped or scattered small tumor nests (with > 20% of the tumor area showing these features). RESULTS: Of the 159 tumors examined, 38 (24%) were type A and 121 (76%) were type B. Type B tumors had a significantly deeper invasion depth, more frequent lymphatic permeation and lymph node metastasis, more prominent active fibroblastic stroma, and less frequent inflammatory cell infiltration (P < 0.05). Both univariate (P < 0.05) and multivariate (P < 0.05) analysis of the patients' survival showed that the prognosis for patients with type B tumors was significantly worse than for patients with type A tumors. CONCLUSIONS: This study showed that tumor nest configuration, which corresponded to the behavior of tumor cells against stromal cells, correlated well with the aggressiveness of the tumor.

Adult↗

PubMed2001

Staggered field effect on the one-dimensional S = 1/2 antiferromagnet Yb4As3.

Inelastic neutron scattering measurements of magnetic excitations in the charge-ordered state of Yb4As3 have been performed under magnetic field up to about 6 T. By applying a magnetic field, the spectrum at the one-dimensional wave vector q = 1 [ pi/d] changes drastically from a broad one corresponding to the spinon excitation continuum of the one-dimensional S = 1 / 2 spin system to a sharp one at a finite energy, indicating the opening of an energy gap in the system. The magnetic field dependence of the gap is well fitted by the power law H2/3. The experimental result gives strong evidence for the existence of a staggered field alternating along Yb3+ chains induced by the Dzyaloshinsky-Moriya interaction.

Journal Article↗

PubMed2001

Establishment of a novel species- and tissue-specific metastasis model of human prostate cancer in humanized non-obese diabetic/severe combined immunodeficient mice engrafted with human adult lung and bone.

Bone is the most common site of metastasis in prostate cancer (PC), and to generate an animal model to investigate the basis of the unique organ tropism of PC cells for bone, we engrafted humanized non-obese diabetic/severe combined immunodeficient (NOD/SCID-hu) mice with human adult bone (HAB) and lung (HAL). Human PC cell lines LNCaP (1 x 10(7)) and PC-3 (5 x 10(6)) were injected into male NOD/SCID-hu mice via the lateral tail vein at 3-4 weeks after implantation. At 8 weeks after the injection, LNCaP and PC-3 cells had metastasized specifically to HAB in 35 and 65%, respectively, of the mice. The tumors formed by LNCaP appeared to be the osteoblastic type, whereas the PC-3 tumors consisted of osteolytic lesions without any surrounding osteogenic response. A feature of experimental metastasis of PC in NOD/SCID-hu mice was its specificity for HAB tissue. Human PC cells had no or very low metastatic potential in regard to implanted HAL, mouse bone, or native mouse bone. These findings indicate that metastasis of PC cells to HAB is both species and tissue specific. The availability of this small animal model could provide a useful tool for identifying and analyzing important features of the human PC metastatic process that cannot be addressed in conventional metastasis models.

Aged↗