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Biomedical subjects

T Shimoda

Publications and source records attributed to T Shimoda.

At least 19 recordsLinked to original sources

Clinicopathological significance of microscopic abscess formation at the invasive margin of advanced low rectal cancer.

BACKGROUND: The aim of this study was to evaluate the clinicopathological significance of microscopic abscess formation (MAF) at the invasive front of advanced low rectal cancer. METHODS: The clinicopathological features of 226 consecutive patients with low rectal cancer, who underwent curative resection between May 1997 and December 2002, were analysed. RESULTS: Fifty-seven (25.2 per cent) of the 226 tumours had MAF and 169 (74.8 per cent) did not. Patients with tumours showing MAF were more likely to have extended surgery than those without MAF: 47 versus 31.4 per cent respectively underwent non-sphincter-preserving surgery (P=0.029) and 82 versus 60.9 per cent underwent lateral lymph node dissection (P=0.003). The incidence of lymph node metastases was lower in patients with MAF (30 versus 53.3 per cent; P=0.002). Univariable analysis of disease-free survival revealed that depth of invasion (P<0.001), lymph node status (P<0.001), histological type (P=0.035), lymphatic invasion (P<0.001), venous invasion (P<0.001), perineural invasion (P<0.001), focal dedifferentiation (P<0.001) and MAF (P<0.001) were significant prognostic factors. Multivariable analysis showed that lymph node status (P<0.001), perineural invasion (P=0.002), venous invasion (P=0.033) and MAF (P=0.012) remained independent prognostic factors. CONCLUSION: MAF may reflect indolent tumour behaviour and a more favourable outcome in patients with advanced low rectal cancer.

Abscess↗

Why does Japan have a high incidence of gastric cancer? Comparison of gastritis between UK and Japanese patients.

BACKGROUND AND AIMS: The incidence of gastric cancer in Japan is four times higher than in the UK. It usually arises in a stomach with corpus predominant or pangastritis that has undergone extensive atrophy and intestinal metaplasia. We hypothesised that a Japanese population would have a more severe gastritis with a corpus predominant or pangastritis pattern and a greater degree of atrophy and intestinal metaplasia than that found in the UK. To test this we designed a comparative trial. METHODS: A total of 252 age matched consecutive patients were recruited from the endoscopy services in Leeds and Tokyo. In each centre, 21 patients were prospectively selected from each decennial, between the ages of 20-80 years. All had epigastric discomfort as their predominant symptom. Patients with peptic ulcer, cancer, and oesophagitis were excluded. Five gastric biopsies were examined by two histopathologists using the updated Sydney system. Helicobacter pylori infection was assessed by histology and culture of biopsies and enzyme linked immunosorbent assay and immunoblot of plasma. RESULTS: Gastritis was found by both pathologists in 59 (47%) UK and 76 (60%) Japanese patients (chi(2) test, p = 0.04). In those patients with gastritis, corpus predominant or pangastritis was commoner in the Japanese (63% Japan v 36% in the UK (chi(2) test, p = 0.003) Atrophy and intestinal metaplasia were more extensive and severe (Mann-Whitney U test, p<0.001) and chronic inflammation and polymorph activity were also greater, especially in the corpus (Mann-Whitney U test, p<0.001). Fifty three of 59 UK gastritis patients (90%) and 67/76 (88%) (chi(2) test, p = 1) Japanese gastritis patients were positive for H pylori. Using a previously described "gastric cancer risk index" among H pylori positive patients, there were significantly more Japanese than UK subjects with a "high risk" score. CONCLUSION: In Japanese as opposed to English patients, gastritis is more prevalent and severe with more corpus predominant atrophy and intestinal metaplasia. These differences may partially explain the higher incidence of gastric cancer in Japan.

Adult↗

Measurement of a long electronic spin relaxation time of cesium atoms in superfluid helium.

The longitudinal electronic spin relaxation time of Cs atoms optically polarized in superfluid helium (He II, 1.5 K) has been measured with special care to cope with a serious decrease in the number of Cs atoms in the observation region. This decrease, mainly caused by helium convection in introducing the atoms into He II by laser sputtering, was significantly reduced using a new atom implantation method. Combined with a careful correction for the number of atoms, we have determined the relaxation time to be 2.24(19) s or longer, roughly twice as long as that in solid He.

Journal Article↗

Extranodal metastasis is an indicator of poor prognosis in patients with gastric carcinoma.

BACKGROUND: The aim of this study was to determine the clinical significance and prognostic impact of extranodal metastasis (EM) in gastric carcinoma. METHODS: The study included 1023 patients who underwent gastrectomy with lymphadenectomy for primary gastric carcinoma between January 1993 and December 1996. EM was defined as the presence of tumour cells in extramural soft tissue that was discontinuous with either the primary lesion or locoregional lymph nodes. RESULTS: EM was detected in 146 (14.3 per cent) of the 1023 patients and in 1060 (3.0 per cent) of the 35 811 nodules that were retrieved as 'lymph nodes' from adipose connective tissues. The incidence of EM was significantly higher in patients with tumours that were large (diameter 10 cm or more), infiltrative, deeply invading or undifferentiated and in those with lymph node, peritoneal or liver metastases, or lymphatic or vascular involvement. After curative operation overall survival was significantly worse for patients with EM than those without (P < 0.001). Multivariate analysis identified EM as an independent prognostic factor (hazard ratio 1.82 (95 per cent confidence interval 1.23 to 2.71); P = 0.003). CONCLUSION: EM is an independent prognostic factor and should therefore be included in the tumour node metastasis (TNM) staging system.

Aged↗

Allelic loss analysis of early-stage flat-type colorectal tumors.

BACKGROUND: Flat-type colorectal tumors are rare, but are known for their unusual flat morphology and aggressive clinical behavior despite their small size. To identify distinct genetic alterations, loss of heterozygosity (LOH) analysis was performed on microdissected tissues. MATERIALS AND METHODS: DNA was extracted from multiple microdissected foci in 43 cases of early-stage flat-type colorectal tumors and LOH analysis was performed on 2q, 4q, 5q, 12q, 14q, 15q, 17p, 18q, 18p and 22q. RESULTS: LOH patterns were detected in one of two forms: (i) homogeneous LOH throughout the microdissected foci, which indicated the early acquisition of LOH; and (ii) heterogeneous LOH, which were detected in a part of analyzed foci. Homogeneous and heterogeneous LOH were most frequently detected on 17p (92%) followed by 18q (81%), 18p (81%), 5q (61%), 22q (51%), 14q (44%), 15q (41%), 2q (39%), 12q (36%) and 4q (32%). Homogeneous LOH was detected most frequently on 17p (68%) followed by 18p (53%), 18q (53%), 22q (34%) and 12q (27%). The average fractional allelic loss (FAL) for heterogeneous and homogeneous LOH was 0.57 and the average FAL for homogeneous LOH was 0.37. CONCLUSIONS: Early flat-type colorectal tumors frequently shows the early occurrence of multiple LOH including 17p, 18p, 18q and 22q, which is coupled with additional LOH of other loci either simultaneously or in the early clonal progression phase. The extent and sequences of LOH may be the mechanisms responsible for the aggressive clinical behaviors of these tumors.

Adult↗

Surgery for clinical T3 carcinomas of the upper thoracic oesophagus and the need for new strategies.

BACKGROUND: Patients with T3 carcinomas have a dismal prognosis, even after complete resection of the primary tumour and metastatic nodes. This study focused on the clinicopathological characteristics and outcomes after surgical resection of clinical T3 carcinomas of the upper thoracic oesophagus. METHODS: Between January 1988 and February 2000, 888 consecutive patients underwent surgical removal of carcinomas of the thoracic oesophagus or oesophagogastric junction at the National Cancer Centre Hospital, Japan. The case records of 51 consecutive patients with clinical T3 tumours of the upper thoracic oesophagus were analysed retrospectively. RESULTS: No patient received preoperative therapy. Complications occurred in 41 (80 per cent). In-hospital and 30-day postoperative mortality rates were 10 and 4 per cent respectively. Gross residual primary tumour or metastasis in regional nodes invading adjacent structures was noted in 14 patients (27 per cent) and incomplete resection including microscopic residual tumour in 23 (45 per cent). Overall 3- and 5-year survival rates were 20 and 12 per cent; median survival was 13.1 months. CONCLUSION: Surgical resection of clinical T3 carcinomas of the upper thoracic oesophagus is associated with a high postoperative complication rate, incomplete resection and unsatisfactory outcome. Reconsideration of the surgical treatment strategy for these tumours is needed.

Adult↗

A case of chondroma of the tongue.

Chondroma of the tongue represents a very rare benign tumor at this site, with very few reports of pure chondroma (no components of adipose, fibrous or bony tissue) existing. This report presents the case of a 17-year-old man with chondroma arising at the center of the tongue.

Adolescent↗

Arundic acid (ONO-2506) ameliorates delayed ischemic brain damage by preventing astrocytic overproduction of S100B.

After focal cerebral ischemia, the infarct volume increases rapidly within acute infarct expansion (initial 12 to 24 h) and continues slowly during delayed infarct expansion (25 to 168 h). While acute infarct expansion represents progressive necrosis within the ischemic core, delayed infarct expansion starts as disseminated apoptotic cell death in a narrow rim surrounding the infarct border, which gradually coalesces to form a larger infarct. Discovery of a distinct correlation between reactive astrogliosis along the infarct border and delayed infarct expansion in the rodent ischemia model led us to investigate the possible causal relationship between the two events. Specifically, the calcium binding protein S100B exerts detrimental effects on cell survival through activation of various intracellular signaling pathways, resulting in altered protein expression. Arundic acid [(R)-(-)-2-propyloctanoic acid, ONO-2506] is a novel agent that inhibits S100B synthesis in cultured astrocytes. In the rodent ischemia model, this agent was shown to inhibit both the astrocytic overexpression of S100B and the subsequent activation of signaling pathways in the peri-infarct area. Concurrently, delayed infarct expansion was prevented, and neurologic deficits were promptly ameliorated. The results of subsequent studies suggest that the efficacy of arundic acid is mediated by restoring the activity of astroglial glutamate transporters via enhanced genetic expression.

Animals↗

Control of carrier density by self-assembled monolayers in organic field-effect transistors.

Organic thin-film transistors are attracting a great deal of attention due to the relatively high field-effect mobility in several organic materials. In these organic semiconductors, however, researchers have not established a reliable method of doping at a very low density level, although this has been crucial for the technological development of inorganic semiconductors. In the field-effect device structures, the conduction channel exists at the interface between organic thin films and SiO(2) gate insulators. Here, we discuss a new technique that enables us to control the charge density in the channel by using organosilane self-assembled monolayers (SAMs) on SiO(2) gate insulators. SAMs with fluorine and amino groups have been shown to accumulate holes and electrons, respectively, in the transistor channel: these properties are understood in terms of the effects of electric dipoles of the SAMs molecules, and weak charge transfer between organic films and SAMs.

Computer Simulation↗

Long-term follow-up study of gastric adenoma/dysplasia.

BACKGROUND AND STUDY AIMS: The natural course of gastric adenoma/dysplasia, regarded as a precancerous lesion, is still uncertain. PATIENTS AND METHODS: From 1976 to 2000, 48 lesions in 43 patients (37 men, six women; mean age 59 years) were diagnosed as having gastric adenoma/dysplasia based on their first biopsies. These lesions were followed for a median of 4.7 years (mean 6 years, range 3-18 years) to evaluate the risk of progression to invasive carcinoma. Retrospectively, histological diagnoses of the biopsy and resected specimens were reclassified according to the Vienna classification of gastrointestinal epithelial neoplasia, and macroscopic changes were evaluated. RESULTS: The diagnosis at first biopsy of the 48 lesions was low-grade adenoma/dysplasia (LGD; category 3) in 38 cases and high-grade adenoma/dysplasia (HGD; category 4) in 10 cases. Ninety-seven percent of the LGD (category 3) lesions (37 of 38) showed no histological changes during the follow-up period; the remaining lesion progressed to noninvasive carcinoma (category 4). Macroscopically, 84 % (32 of 38) of the LGD lesions (category 3) showed no remarkable changes in size, while 11 % (four of 38) shrank and 5 % (two of 38) grew larger. Nine of the 10 HGD lesions (category 4) remained histologically unchanged, while the other progressed to intramucosal carcinoma (category 5). Macroscopically, four of the 10 HGD lesions (category 4) (40 %) showed no remarkable changes in size, while the remaining six (60 %) grew larger. CONCLUSIONS: LGD lesions (category 3) have a quite low risk of progressing to HGD or noninvasive carcinoma (category 4), and were never observed to progress to invasive carcinoma (category 5). HGD lesions (category 4) occasionally progressed to intramucosal carcinoma (category 5), with no instance of invasion into the submucosa or beyond.

Adenoma↗

Anaemia in relation to low bioavailability of dietary iron among school-aged children in the Aral Sea region, Kazakhstan.

This study investigates anaemia related to the sufficiency of dietary iron intake of school-aged children in the Kzyl-Orda region of Kazakhstan. We conducted a cross-sectional study of 97 school-aged children living in Kzyl-Orda. Blood samples were collected for measuring haemoglobin. Dietary intake data were obtained from 24-h dietary recalls. Iron bioavailability was estimated with algorithms adjusting for absorption enhancers (meat, fish and poultry, and vitamin C) and inhibitors (tea and phytates) consumed in the same meal. The median total iron intakes were adequate compared with the median basal iron requirement; however, the median bioavailable iron intakes were well below the median absorbed iron requirement. Available iron was 6.9-7.2% of the total iron intake after adjusting for the absorption enhancers, and was reduced by 3.1-4.4% after adjusting for both enhancers and inhibitors. After adjustment for energy intake, higher iron intake was significantly associated with a decreased prevalence of anaemia (odds ratio, 0.39; 95% confidence interval, 0.16-0.93; P=0.034). Some evidence suggested an association between bioavailable iron intake after adjustment of absorption enhancers and inhibitors (odds ratio, 0.43; 95% confidence interval, 0.18-1.01; P=0.053). In conclusion, low bioavailability of dietary iron seems related to anaemia in the region. Although iron fortification or supplementation programmes can be useful for promoting the anaemia prevention control programme, further efforts for nutritional education suited for family level dietary practice are necessary.

Absorption↗

The effects of topical application of phytonadione, retinol and vitamins C and E on infraorbital dark circles and wrinkles of the lower eyelids.

BACKGROUND: Infraorbital dark circles and wrinkles of the lower eyelids are a cosmetic problem, especially with age. AIMS: To determine whether a gel containing 2% phytonadione, 0.1% retinol and 0.1% vitamins C and E is effective in reducing dark under-eye circles and wrinkles of the lower eyelids in healthy Japanese adults. PATIENTS/METHODS: Fifty-seven adult Japanese volunteers with dark under-eye circles and wrinkles were enrolled in an open label study. The gel formulation was applied twice daily to the lower eyelid site for 8 weeks. Haemostasis, pigmentation and wrinkles were evaluated by a physician and by the patients themselves, using a digital camera and a visual analogue scale respectively, after 4 and 8 weeks of treatment. RESULTS: Topical application of the gel decreased not only haemostasis but also wrinkles after 8 weeks of treatment. Of 57 patients, 27 (47%) had reductions in haemostasis. Wrinkles were also decreased in some patients. However, pigmentation was not clearly removed by this gel. CONCLUSIONS: Topical application of the gel containing 2% phytonadione, 0.1% retinol, 0.1% vitamin C and 0.1% vitamin E was fairly or moderately effective in reducing dark under-eye circles, especially in cases of haemostasis, over a short treatment period in healthy Japanese adults. This treatment also slightly decreased wrinkles.

Journal Article↗

Bronchial hyperresponsiveness and airway inflammation in adolescents with asymptomatic childhood asthma.

BACKGROUND: About 70% of childhood asthmatics become free of asthma-related symptoms during adolescence. Little is known about bronchial hyperresponsiveness (BHR) and airway inflammation in young adults with "outgrown" childhood asthma. METHODS: We studied 61 nonsmoking medical students (18 intermittent mild asthmatics, 23 students with outgrown childhood asthma but free of asthma-related symptoms for 10 years (asymptomatic asthmatics) and 20 healthy students). BHR and lung function were measured, and induced sputum samples analyzed for eosinophil count, eosinophilic cationic protein (ECP), granulocyte-macrophage colony stimulating factor (GM-CSF), and tumor necrosis factor-alpha (TNF-alpha). RESULTS: BHR was still present in most asymptomatic asthmatics, but it was milder compared with healthy students. Only three subjects with previous asthma had no BHR and no signs of airway inflammation. Percentages of eosinophil, and ECP, TNF-alpha and GM-CSF concentrations in induced sputum of mild asthmatics and asymptomatic asthma groups were higher than in the healthy group. In asymptomatic asthmatics group, the duration of asthma, sputum eosinophil percentage, and the level of TNF-alpha in sputum correlated significantly with BHR. CONCLUSIONS: Only a few subjects with longstanding asymptomatic asthma could be considered as cured; most asymptomatic asthmatics continued to exhibit BHR and signs of airway inflammation. The outcome of childhood asthma and BHR was associated with the degree of airway inflammation and the duration of childhood asthma.

Adolescent↗

Self-reported rate of eating correlates with body mass index in 18-y-old Japanese women.

OBJECTIVE: To examine associations between rate of eating and macronutrient and dietary fiber intake, and body mass index (BMI). DESIGN: Cross-sectional study. SUBJECTS: A total of 1695 18-y-old female Japanese dietetic students. MEASUREMENTS: Macronutrient intake (protein, carbohydrate, and fat) and dietary fiber intake were assessed over a 1-month period with a validated, self-administered, diet history questionnaire. Body height and weight and rate of eating (according to five categories) were self-reported. RESULTS: Among the nutrients examined, only dietary fiber intake weakly, but significantly, and negatively correlated with BMI in a multiple regression analysis. The rate of eating showed a significant and positive correlation with BMI. The mean BMI was higher by 2.2, 1.5, 1.0, and 0.5 kg/m(2) in the 'very fast', 'relatively fast', 'medium', and 'relatively slow' groups, respectively, compared with the 'very slow' rate of eating group. This correlation remained evident after adjustment for nutrient intake. CONCLUSIONS: Rate of eating showed a significant and positive correlation with BMI, whereas only dietary fiber intake showed a weak correlation with BMI.

Adolescent↗

Pranlukast, a cysteinyl leukotriene receptor 1 antagonist, attenuates allergen-specific tumour necrosis factor alpha production and nuclear factor kappa B nuclear translocation in peripheral blood monocytes from atopic asthmatics.

BACKGROUND: The cysteinyl leukotriene receptor 1 (cysLTR1) antagonists are useful for oral treatment of bronchial asthma. The underlying mechanism of cysLTR1 antagonists on inhibition of inflammatory cytokine production is yet to be determined. OBJECTIVE: The present study was designed to determine the effect of pranlukast, a cysLTR1 antagonist, on production of inflammatory cytokines by allergen-stimulated peripheral blood monocytes (PBM) from atopic asthmatics. METHODS: PBM were obtained from normal control (n = 10) and Dermatophagoides farinae (Der f) allergen-sensitized atopic asthmatics (n = 12), and were cultured in the presence of Der f allergen. The production of TNF-alpha and nuclear-translocation of nuclear factor kappa B (NF-kappa B) was determined. In atopic asthmatics, pranlukast, tacrolimus or dexamethasone was added before stimulation by Der f. The additive effect of pranlukast and dexamethasone was also determined. RESULTS: PBM from atopic asthmatics cultured with Der f exhibited a significant increase in TNF-alpha production and nuclear translocation of NF-kappa B compared with normal control (P < 0.01). Pranlukast, tacrolimus and dexamethasone significantly inhibited production of TNF-alpha and nuclear-translocation of NF-kappa B in PBM of atopic asthmatics (P < 0.01). An additive effect of pranlukast on low-dose dexamethasone was also demonstrated. However, LTD4 did not induce TNF-alpha production or NF-kappa B nuclear translocation. CONCLUSION: Our results suggest that pranlukast may inhibit TNF-alpha production via suppression of NF-kappa B activation through pathways distinct from cysLTR1 antagonism.

Adult↗