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T Iwase

Publications and source records attributed to T Iwase.

At least 37 records · Page 2Linked to original sources
PubMed2001

Intracranial subdural hematoma after puncture of spinal meningeal cysts.

A patient is reported with an intracranial subdural hematoma after puncture of spinal meningeal cysts. In this case, spinal meningeal cysts were diagnosed by myelography. No intracranial subdural hematoma was detected immediately after myelography. Deterioration in the patient's level of consciousness occurred after puncture of the cysts. The authors speculated that the cerebrospinal fluid pressure dropped rapidly when the spinal meningeal cysts were punctured. This displaced the cerebral bridging veins downward, tearing them and resulting in an intracranial subdural hematoma.

Central Nervous System Cysts↗
PubMed2001

Development of an automated method for detecting mammographic masses with a partial loss of region.

Recently, we have been developing several automated algorithms for detecting masses on mammograms. For our algorithm, we devised an adaptive thresholding technique for detecting masses, but our system failed to detect masses with a partial loss of region that were located on the edge of the film. This is a common issue in all of the algorithms developed so far by other groups. In order to deal with this problem, we propose a new method in the present study. The partial loss masses are identified by their similarity to a sector-form model in the template matching process. To calculate the similarity, four features are applied: 1) average pixel value; 2) standard deviation of pixel values; 3) standard correlation coefficient defined by the sector-form model; and 4) concentration feature determined from the density gradient. After employing the new method to 335 digitized mammograms, the detection sensitivity for the partial loss masses jumped from 70% to 90% when the number of false positives was kept constant (0.2/image). Moreover, a combination of the existing method and the new method improved the true-positive rate up to 97%. Such results indicate that the new technique may improve the performance of our computer-aided diagnosis system for mammographic masses effectively.

Algorithms↗
PubMed2001

CD14 is expressed and released as soluble CD14 by human intestinal epithelial cells in vitro: lipopolysaccharide activation of epithelial cells revisited.

Human endothelial as well as epithelial cells were shown to respond to lipopolysaccharides (LPSs). However, the expression and release of CD14 by these so-called CD14-negative cells have not been studied in detail. We investigated three human intestinal epithelial cell lines (ECLs), SW-480, HT-29, and Caco-2, for their expression of CD14 and CD11c/CD18 as well as their responsiveness to endotoxins. Fluorescence-activated cell sorter analysis revealed no expression of CD11c/CD18, but there was low expression of membrane-bound CD14 on HT-29, Caco-2, and SW-480 ECLs. Both Western blotting and reverse transcription-PCR confirmed the CD14 positivity of all three intestinal ECLs. No substantial modulation of CD14 expression was achieved after 6, 8, 18, 24, and 48 h of cultivation with 10-fold serial dilutions of LPS ranging from 0.01 ng/ml to 100 microg/ml. Interestingly, soluble CD14 was found in the tissue culture supernatants of all three ECLs. Finally, only HT-29 and SW-480, and not Caco-2, cells responded to LPS exposure (range, 0.01 ng/ml to 100 microg/ml) by interleukin 8 release. Thus, we show that HT-29, SW-480, and Caco-2 human intestinal ECLs express membrane-bound CD14. As Caco-2 cells did not respond to LPS, these cell lines might be an interesting model for studying the receptor complex for LPS. The fact that human intestinal epithelial cells are capable not only of expression but also of release of soluble CD14 may have important implications in vivo, e.g., in shaping the interaction between the mucosal immune system and bacteria in the gut and/or in the pathogenesis of endotoxin shock.

Blotting, Western↗
PubMed2001

Acute and chronic effects of surgical thromboendarterectomy on exercise capacity and ventilatory efficiency in patients with chronic thromboembolic pulmonary hypertension.

OBJECTIVE: To assess acute and chronic effects of surgical thromboendarterectomy on exercise capacity and ventilatory efficiency in patients with chronic thromboembolic pulmonary hypertension (CTEPH). DESIGN: Cardiopulmonary exercise testing was performed in 20 patients with CTEPH before thromboendarterectomy (baseline), one month after (early phase), and four months after (late phase). Peak oxygen uptake (peak VO(2)) and the ventilatory response to carbon dioxide production (VE-VCO(2) slope) were measured for assessment of exercise capacity and ventilatory efficiency. Right heart catheterisation was performed in all patients before and one month after surgery. RESULTS: Baseline peak VO(2) decreased and VE-VCO(2) slope increased along with the increase in pulmonary vascular resistance in patients with CTEPH. After thromboendarterectomy, the VE-VCO(2) slope decreased greatly from baseline to the early phase (mean (SD), 50 (9) to 37 (7), p < 0.05) and reached a steady level thereafter. In contrast, a continued increase in peak VO(2) was noted from the early to the late phase (16.9 (4.1) to 21.1 (5.0) ml/kg/min, p < 0.05). The decrease in the VE-VCO(2) slope from baseline to the early phase, but not the increase in peak VO(2), correlated strongly with the decrease in pulmonary vascular resistance after surgery (r = 0.75, p < 0.01). CONCLUSIONS: Thromboendarterectomy may cause an immediate improvement in ventilatory efficiency, possibly through its beneficial haemodynamic effects. In contrast, exercise capacity may continue to improve towards the late phase, reflecting peripheral adaptation to exercise.

Acute Disease↗
PubMed2000

Genetic polymorphisms of human melatonin 1b receptor gene in circadian rhythm sleep disorders and controls.

Recent studies suggest that melatonin 1b (Mel1b) receptor, as well as melatonin 1a (Mel1a) receptor, is involved in the modulation of circadian rhythms in mammals. Mutational analysis was performed in the entire coding region of the human Mel1b receptor gene using genomic DNA from sleep disorder subjects. We have identified two missense mutations, G24E and L66F. However, neither is likely to be associated with sleep disorders in our study population. One of the subjects with non-24-h sleep-wake syndrome carries missense mutations in both the Mel1a and Mel1b receptor genes.

Adult↗
PubMed2000

Mammographic and clinicopathological features of mucinous carcinoma of the breast.

BACKGROUND: We attempted to improve the effectiveness of diagnostic techniques in mammographic imaging of mucinous carcinoma of the breast by defining the characteristics of mammographic images and investigating correlations between these images and various clinicopathological findings. METHODS: Clinicopathological investigations of 92 lesions in 90 cases of mucinous carcinoma of the breast were made. Mammography demonstrated 80 lesions with identical tumor shadow characteristics and these were divided into three patterns, circumscribed, indistinct and blended. Correlations between clinicopathological findings and mammographic images were investigated. RESULTS: Patients with mucinous carcinoma of the breast usually present with a palpable mass. The lymph node metastasis rate in this study was low and prognosis in the early postoperative period was satisfactory. On mammograms, the circumscribed pattern was the most frequent. The investigation of the correlation between histological sub-type and mammographic pattern showed a high percentage of pure type lesions exhibited in the circumscribed pattern while those of mixed histologic type often showed the indistinct pattern. Calcification frequency demonstrated on mammography was 75% for the indistinct and mixed patterns, and approximately 50% for the circumscribed pattern. A high rate of calcification seen outside the tumor shadow suggested a high frequency of invasion and the spread of cancer to neighboring tissues. The circumscribed pattern was least frequently associated with lymph node metastasis, followed by the indistinct and blended patterns in that order. CONCLUSION: Investigation of clinicopathological factors and mammographic findings in mucinous carcinoma of the breast suggests that mammography provides clinically valuable information for the treatment of this disease. These findings indicate the importance of careful mammographic observation at the time of diagnosis.

Adenocarcinoma, Mucinous↗
PubMed2000

A case of metastatic breast cancer achieving complete response by combination therapy with 5'-deoxy-5-fluorouridine and cyclophosphamide.

Recently there have been several reports on the effectiveness of combination chemotherapy with 5'-deoxy-5-fluorouridine (5'-DFUR) and cyclophosphamide (CPA) for treating recurrent breast cancer. We report a case in which treatment of local recurrence and lung metastases responded was remarkably effective by this combination chemotherapy. A 45-year-old woman underwent modified radical mastectomy for left breast cancer (T2N0M0) three years previously. Involvement of a left supraclavicular lymph node (ScLN) and multiple lung metastases were revealed 2 years and 6 months after the operation. First, we opted for systemic endocrine therapy with local irradiation for the lung metastases and ScLN. However the lung metastases were found to have increased on chest x-ray 2 months after treatment, showing progressive disease (PD). A locally recurrent new lesion sized 2 x 2 cm had also developed. Thus, we changed the treatment to combination chemotherapy with 5'-DFUR 800 mg/body and oral CPA 100 mg/body once a day. The lung metastases had disappeared on chest x-ray and the local recurrence was not palpable after 7 weeks of the new treatment. Thymidine phosphorylase (dThdPase) immunostaining of the primary tumor was strongly positive in almost all cancer cells. We discuss the mechanism of the increased efficacy of combination chemotherapy with 5'-DFUR and CPA.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

Cloning and expression of the chicken immunoglobulin joining (J)-chain cDNA.

The J chain is a component of polymeric immunoglobulin (Ig) molecules and may play an important role in their polymerization and the transport of polymeric Ig across epithelial cells. In this study, the primary structure of the chicken J chain was determined by sequencing cDNA clones. The cDNA had an open reading frame of 476 nucleotides encoding a putative protein of 158 amino acid residues including the signal sequence. The 3' untranslated region consisted of 1216 nucleotides and a poly(A) tail. The deduced amino acid sequence of the chicken J chain had a high degree of homology to that of human, cow, rabbit, mouse, frog, and earthworm, with eight conserved Cys residues identical to the mammalian J chains. Northern blot hybridization performed with total RNA from various chicken tissues revealed high levels of J-chain mRNA expression in spleen, intestine, Harderian gland, and bursa of Fabricius, and low levels in the thymus. The J chain was expressed in the bursa as early as day 15 of embryogenesis. These data indicated that the chicken J-chain gene displays a high degree of homology with that of other species, and is expressed at an early stage of development of the chicken immune system.

Amino Acid Sequence↗
PubMed2000

No association of the 5' promoter region polymorphism of CYP17 with breast cancer risk in Japan.

To examine the association between breast cancer risk and a T-to-C substitution polymorphism at the 5' promoter region of CYP17, a case-control study was conducted at Aichi Cancer Center Hospital in Japan. Subjects were 144 histologically confirmed breast cancer patients diagnosed in the past 4 years and 166 hospital controls without cancer. Allele frequency among controls was 44.9% (95% confidence interval; 39.5 - 50.2) for C allele. Odds ratio (OR) of the polymorphism relative to TT-genotype was 0.97 (0.58 - 1.64) for TC-genotype and 0.81 (0.39 - 1.68) for CC-genotype. Subgroup analyses revealed that the OR was not statistically significant for the subgroups stratified by interval after diagnosis, age at menarche, age at first birth, menopausal status, body mass index, and mother / sisters' history of breast cancer. Consistent with previous studies conducted in other countries, the 5' promoter region polymorphism of CYP17 affected breast cancer risk of Japanese women to a limited extent. Although this is not a large-scale case-control study with population controls, these findings provide enough information to discourage further studies on the association between this polymorphism and breast cancer risk in Japan at large, and suggest that this polymorphism is useless for breast cancer risk estimation.

Adult↗
PubMed2000

[Novel extracorporeal granulocyte apheresis column inhibits myocardial reperfusion injury: future clinical applications].

OBJECTIVES: Leukocyte infiltration is very important in myocardial ischemia/reperfusion injury. A new extracorporeal circulation therapy using a granulocyte-apheresis column (G-1) has recently been proved to be effective and safe in patients with rheumatoid arthritis and with ulcerative colitis. This study investigated whether this therapy would reduce myocardial ischemia/reperfusion injury. METHODS: Rabbits were subjected to 30 min ischemia followed by 180 min reperfusion with no treatment (control group: n = 12); or treated with extracorporeal blood circulation (2 ml/min) passing through the G-1 (G-1 group: n = 12), or sham column (sham group: n = 12). Infarct size was determined by tetrazolium staining and expressed as a percentage of the area at risk. RESULTS: Infarct size in the G-1 group (15.9 +/- 3.4%) was significantly (p < 0.01) smaller than in the control (34.7 +/- 3.9%) and sham (35.2 +/- 4.1%) groups. Granulocyte emigration into the ischemic myocardium assessed by histopathological score was significantly (p < 0.01) less in the G-1 group (0.58 +/- 0.17) than in the sham group (1.42 +/- 0.26). There was a significant (r = 0.78, p < 0.0001) positive correlation between this score and infarct size. Flow cytometry showed alterations in the adhesion molecule expression on granulocytes during the passage through the G-1, but not sham, columns as a low L-selectin and high Mac-1 form, which is associated with the inability to home to the inflamed site. CONCLUSIONS: Extracorporeal circulation with the G-1 column, a newly-developed clinically applicable therapy, appears to reduce infarct size at least in part by limiting the emigration capacity of granulocytes into the ischemic myocardium.

Animals↗
PubMed2000

Intrapulmonary lymph nodes detected by exploratory video-assisted thoracoscopic surgery: appearance of helical computed tomography.

The objective of this study was to analyze helical computed tomography (CT) findings of intrapulmonary lymph nodes (IPLNs), and to evaluate the diagnostic procedures to prevent unnecessary exploratory surgery. Between April 1997 and March 2000, we performed exploratory video-assisted thoracoscopic surgery (E-VATS) in 42 patients and in 8 patients (4 men, 4 women; 48 to 75 years of age, mean 57 years) IPLN was pathologically proven. Retrospectively, the appearances of IPLN in helical CT images were studied in detail. The diameter of the IPLNs varied from 4 to 10mm. Six nodules were located in the lower lobes and 2 nodule was in the lingula. Chest CT showed several malignancy-suggesting associated findings with pleural indentation (2/8), spicular radiation (2/8), fuzzy margins (4/8), and vascular involvement (2/8). Black colored anthracoses in 5 subpleural IPLNs were confirmed by thoracoscopy. One patient with two coin lesions was suggestive of lung metastasis of adenoidcystic carcinoma of the tongue, but one lesion was proven as IPLN, and the other as metastatic carcinoma. In conclusion, it is not possible to distinguish an intrapulmonary lymph node from a malignant lesion using the CT findings preoperatively. Therefore, a pathological study with E-VATS is necessary and sure procedure to exclude malignant disease under the present conditions.

Aged↗
PubMed1999

Aortic arch reconstruction by transluminally placed endovascular branched stent graft.

BACKGROUND: Recently, thoracic aortic stent grafting has emerged as an alternative therapeutic modality for patients with thoracic aortic aneurysms and aortic dissections. However, its application has been limited to descending thoracic aortic aneurysms distal to the aortic arch. We report our initial clinical experience of endovascular branched stent graft repair for aortic arch aneurysms. METHODS AND RESULTS: Endovascular grafting with Inoue branched stent grafts was attempted for 15 patients with thoracic aortic aneurysms and aortic dissections under local anesthesia (n=14) or general anesthesia (n=1). Single-branched stent grafts were used in 14 patients, and a triple-branched stent graft in one. The branched stent grafts were delivered through a 22F or a 24F sheath under fluoroscopic guidance and implanted across the aneurysmal aortic arch. In 2 patients, the single-branched stent graft did not pass through the 22F sheath used. Complete thrombosis of the aneurysm was ultimately achieved in 11 patients (73%). Of 4 persistent leaks, 1 minor leak spontaneously thrombosed and 1 major leak was successfully treated by additional straight stent graft placement. In 1 patient, the right external iliac artery ruptured during the withdrawal of the sheath and was successfully repaired by the implantation of a straight stent graft. One patient with severe stenosis of the aortic graft section was successfully managed by additional stent deployment. Peripheral microembolization to a toe occurred in 1 patient, and cerebral infarction occurred in 1 other patient. Two patients who had failed to receive endovascular stent grafts died during an average follow-up of 12.6 months, 1 of pneumonia and the other of rupture of a concomitant abdominal aortic aneurysm. CONCLUSIONS: This report demonstrates the technical feasibility of endovascular branched stent graft repair for aneurysms located at the aortic arch. Careful, longer follow-up and further extensive clinical trials are awaited toward establishing this technique as a recommendable alternative to surgical treatment of thoracic aortic aneurysms.

Adult↗
PubMed1999

Identification of Cancer Antigens in Breast Cancer by the SEREX Expression Cloning Method.

Enormous strides in cancer immunology have been made during the past decade. This is largely due to the development of methodologies capable of defining the antigenic targets on cancer cells that elicit a host immune response. The molecular cloning of antigens recognized by cytotoxic T cells by Boon and his colleagues has provided a growing list of tumor antigens, particularly for melanoma, that allows detailed monitoring of T cell responses to these antigens and offers promising targets for cancer vaccine development. An alternative new method, SEREX, for the serological identification of cancer antigens has been developed by Pfreundschuh and his colleagues. SEREX can be applied to all types of cancer including breast cancer that have been unapproachable by using cytotoxic T cells and thus offers an opportunity to define a vast range of cancer antigens. Toward thedevelopment of a vaccine for breast cancer, we have begun using SEREX to study breast cancer and have identified a few promising cancer antigens. Each antigen is now being critically evaluated as a possible vaccine target.

Journal Article↗
PubMed1999

Correlation of Allelic Loss with Poor Postoperative Survival in Breast Cancer.

BACKGROUND: Allelic losses of tumor suppressor genes or the chromosomal regions harboring them in the DNA of tumor cells may become useful postoperative prognostic indicators. METHODS: To examine whether specific allelic losses correlate with postoperative survival in a five-year prospective follow-up, we tested tumors from a cohort of 504 breast cancer patients for allelic loss of 18 microsatellite markers representing either known tumor suppressor genes or regions where genetic alterations are frequent in breast tumors. RESULTS: Patients with allelic loss at 1p34, 3p25, 8p22, 13q12, 17p13.3, or 17q21.1 had a significantly higher risks of postoperative mortality compared withthose whose tumors retained both alleles at those loci (at 1p34, the 5-year mortality rate was 23% among patients with loss vs 10% with retention, p 0.0100; at 3p25, 22% vs 9%, p =0.0014; at 8p22, 24% vs 7%, p =0.0177; at 13q12, 19%vs 8%, p=0.0093; at 17p13.3, 19% vs 9%, p=0.0078; and at 17q21.1, 17% vs 10%, p =0.0475). CONCLUSION: Allelic losses at these loci can serve as negative prognostic indicators to guide post-operative management, especially in the selection of thosewho will benefit from intensive adjuvant therapies.

Journal Article↗