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Biomedical subjects

T Yoshida

Publications and source records attributed to T Yoshida.

At least 55 records · Page 3Linked to original sources

Pilomatrix carcinoma of the axilla: CT and MRI features.

Pilomatrix carcinoma, a rare malignant soft tissue tumour, is the malignant variant of pilomatricoma. We report a case of pilomatrix carcinoma of the axilla. CT demonstrated a well-circumscribed, sand-like calcified mass. MRI showed diffusely inhomogeneous, mixed signal intensities with inhomogeneous enhancements. The MRI findings were different from those previously reported for pilomatricoma.

Axilla↗

Decomposition of carbon dioxide by metals during gamma irradiation.

We have proposed a technique to enhance the decomposition of carbon dioxide by gamma irradiation. This is possible by putting metal components into CO2 gas to promote the conversion of gamma rays to lower-energy electrons through Compton, photoelectron and cascading electron knock-on events in metals. Numerical simulations using the EGS code indicated that the number of lower-energy electrons ejected from metals into CO2 gas increases with increasing Z number and/or density of the metals; this was supported by the experimental results, i.e., the CO2-containing metals with a higher Z number exhibited a greater efficiency for production of CO. In addition, production of CO could be enhanced by carefully controlling the volume and surface area of metal components as well as the proximity to adjacent metal components. These experimental results successfully demonstrated that modification of the kinds of metal components and metal structures can control the energy and the number of electrons ejected from the metals and can lead to enhancement of production of CO from CO2.

Carbon Dioxide↗

Effects of coupling methods on galvanic corrosion behavior of commercially pure titanium with dental precious alloys.

BACKGROUND: When a dissimilar couple is exposed to corrosive environment, it will normally exhibit a galvanic corrosion. The galvanic corrosion might be influenced by various factors, including type and concentration of electrolyte, surface area ratio between anode and cathode, type of coupling material, and coupling manner. PURPOSE: The purpose of this study was to investigate and compare the galvanic corrosion behavior of commercially pure titanium when coupled with type IV Au alloy, Au-Ag-Pt alloy, and Ag-Au-Pd alloy by different coupling methods. MATERIALS AND METHODS: Couples were prepared by a laser welding or a mechanical adhering method. Electrochemical corrosion studies were conducted in a Ringer's solution at a scanning rate of 0.1 mV/sec in a range from -250 mV to +250 mV with respect to E(OCP). Corrosion parameters (E(OCP), I(CORR), E(CORR)) were obtained. RESULTS: It was found that (i) there was a significant difference between LWC and AJC for three couples (p<0.05), (ii) the crevice line caused all three couples more corrosive than weld joint line, (iii) for both joint, it was found that type (IV) Au alloy exhibited discoloration to some extent. CONCLUSIONS: It is concluded that among the three couples with two different coupling methods, Ti/Ag-Au-Pd couple exhibited best corrosion resistance in a room temperature Ringer's solution.

Corrosion↗

Juvenile form of Alexander disease with GFAP mutation and mitochondrial abnormality.

The authors report a 29-year-old woman with marked atrophy of the cerebellum, medulla oblongata, and spinal cord, dementia, diffuse white matter abnormality on MRI, ragged-red fibers, and R88C mutation in the human glial fibrillary acidic protein (GFAP). Mitochondria DNA (mtDNA) analysis showed a rare polymorphism at A8291G. This mtDNA polymorphism, which has been associated with limb-girdle type mitochondrial myopathy, may modify the clinical symptoms of this juvenile form of Alexander disease with GFAP mutation.

Adult↗

Relationship between active and passive smoking and total serum IgE levels in Japanese women: baseline data from the Osaka Maternal and Child Health Study.

BACKGROUND: Many studies have shown that cigarette smoking is associated with elevated concentrations of total serum IgE. Few studies, however, have examined total IgE in relation to passive smoking exposure, especially in adults. This cross-sectional study investigated the association of active and passive smoking exposure with levels of total serum IgE in Japan. METHODS: Study subjects were 981 pregnant women in Osaka. Total IgE levels were measured using UniCAP 1000 and were defined as elevated if they exceeded 170 ml/UI. Age, gestation, parity, family history of asthma, atopic eczema and allergic rhinitis, indoor domestic pets, family income, education and the mite allergen level in house dust were selected as potential confounding factors. RESULTS: Current smoking of at least 15 cigarettes a day and 8.0 or more pack-years of smoking were independently related to an increased prevalence of elevated total serum IgE (adjusted odds ratios 3.40 and 2.51, 95% confidence intervals 2.12-5.47 and 1.55-4.06, respectively), and both cigarette smoking status and pack-years of smoking were significantly positively associated with total serum IgE levels, especially in subjects with a positive familial allergic history. There was no measurable association of exposure to environmental tobacco smoke (ETS) at home or at work with total serum IgE concentrations among those who had never smoked. CONCLUSIONS: Our results corroborate a positive relationship between active smoking and total serum IgE levels; however, this study failed to substantiate a positive association of ETS exposure with total IgE. Investigations with more precise and detailed exposure measurements are warranted.

Adult↗

Upregulation of p16(INK4A) and Bax in p53 wild/p53-overexpressing crypts in ulcerative colitis-associated tumours.

In ulcerative colitis (UC)-associated tumours, p53 gene mutations and p53 protein overexpression are frequently found in early stages, but the two types of alteration do not always coincide. To clarify this discrepancy, p53 mutations and expression of p53-associated molecules were analysed in UC-associated dysplasias by a combination of microdissection, polymerase chain reaction-direct sequencing and immunohistochemistry at the single crypt level. Mismatch of p53 protein overexpression (+)/mutation (-) or p53 overexpression (-)/gene mutation (+) was found in nine crypts in regenerative mucosa (19 crypts), in 27 in low-grade dysplasia (41), in one in high-grade dysplasia (5) and in 12 in invasive carcinomas (17). Regarding these mismatched crypts of the first type, significant increase in p16(INK4A) and Bax expression was found. The Ki-67 labelling index was depressed in such p53-diffusely positive lesions with the wild-type p53 gene, compared to their p53-diffusely positive and mutant type counterparts. p16(INK4A) was upregulated indirectly as part of the negative feedback, and increase in Bax, directly controlled by wild-type p53, indicates upregulation of apoptosis. No significant relation with p53-related gene products was detected with the p53 protein overexpression (-)/p53 mutation (+) mismatch. Therefore, a tumorigenesis pathway independent of p53 dysfunction appears to exist in association with ulcerative colitis.

Adult↗

Dichotomy between nodal and antinodal quasiparticles in underdoped (La2-xSrx)CuO4 superconductors.

High resolution angle-resolved photoemission measurements on an underdoped (La(2-x)Srx)CuO4 system show that, at energies below 70 meV, the quasiparticle peak is well defined around the (pi/2,pi/2) nodal region and disappears rather abruptly when the momentum is changed from the nodal point to the (pi,0) antinodal point along the underlying "Fermi surface." It indicates that there is an extra low energy scattering mechanism acting upon the antinodal quasiparticles. We propose that this mechanism is the scattering of quasiparticles across the nearly parallel segments of the Fermi surface near the antinodes.

Journal Article↗

Phase I trial of concurrent chemoradiotherapy with docetaxel, cisplatin and 5-fluorouracil (TPF) in patients with locally advanced squamous cell carcinoma of the head and neck (SCCHN).

The aim of this study was to evaluate the efficacy and toxicity of a concurrent chemoradiotherapy using docetaxel, cisplatin and 5-fluorouracil (5-FU) (TPF) in patients with locally advanced squamous cell carcinoma of the head and neck (SCCHN). In total, 19 patients with previously untreated stage III-IV SCCHN were entered onto this trial. Patients received two cycles of chemotherapy. Cycles were repeated every 4 weeks. The starting doses (dose level 1) were docetaxel 60 mg m(-2), cisplatin 70 mg m(-2), and 5-day continuous infusion of 5-FU 600 mg m(-2) day(-1). Radiation was targeted to begin on the first day of chemotherapy, day 1. The total radiation dose to the primary tumour site and neck lymph nodes was between 63.0 and 74.0 Gy. At least three patients were examined at each dose level before advancing to the next level. The maximum-tolerated dose (MTD) of this regimen was docetaxel 60 mg m(-2), cisplatin 60 mg m(-2) and 5-FU 600 mg m(-2) day(-1). The main toxicities were mucositis (grade 3 and 4, 79%), leukocytopenia (grade 3 and 4, 53%), neutropenia (grade 3 and 4, 42%), anaemia (grade 3, 16%), liver dysfunction (grade 3, 11%) and renal dysfunction (grade 2, 11%). The overall response rate was 100%, including 84% complete responses (CRs). This concurrent chemoradiotherapy with TPF was safe and well tolerated. The high CR rate justifies further evaluation of this chemoradiotherapy modality in advanced SCCHN patients.

Aged↗

Analysis of pathological risk factors for lymph node metastasis of submucosal invasive colon cancer.

There are currently no universally accepted indications and criteria for additional surgical resection of the colorectum after endoscopic resection of the submucosal invasive cancer. The purpose of the present study is to establish accurate indications and criteria for additional surgical resection of the colorectum, based on the prediction of lymph node metastasis, after endoscopic resection of the submucosal invasive cancer. We investigated 140 submucosal invasive colorectal cancers and analyzed the pathologic factors of lymph node metastasis. The tumors were evaluated for pathologic factors in the invasive area of the submucosal carcinoma and were compared between the cases with lymph node metastasis and those without lymph node metastasis. Lymph node metastasis was observed in 13 cases (9%). Univariate logistic regression analysis showed that the depth of invasion, cribriform-type structural atypia, absence of lymphoid infiltration, lymphatic permeation, and venous permeation were statistically significant as risk factors for lymph node metastasis. Multivariate logistic regression analysis showed that the important risk factors included, in decreasing order, lymphatic permeation, absence of lymphoid infiltration, cribriform-type structural atypia, venous permeation, and depth of invasion. Submucosal invasion of 2 mm or more, and/or, depth of lymphatic permeation of 2 mm or more are risk factors for lymph node metastasis. The pathologic criteria based on our results for additional colectomy enables greater accuracy selection of patients who will undergo further surgical treatment after endoscopic resection.

Algorithms↗

Allogeneic peripheral blood stem cell transplantation from two- or three-loci-mismatched related donors in adult Japanese patients with high-risk hematologic malignancies.

With the increasing frequency of haploidentical transplantation, it is becoming more important to establish the degree of HLA mismatch that can be accepted. We retrospectively analyzed clinical data of 50 adult Japanese patients with high-risk hematologic malignancies who underwent allogeneic peripheral blood stem cell transplantation (PBSCT) from two- or three-loci-mismatched related donors with HLA class I and II gene disparities in the graft-versus-host direction. They were treated at 20 transplant centers between 1996 and 2002. In all, 18 patients received unmanipulated PBSC, while 32 received purified CD34+ blood cells. Conventional (n=31) or reduced-intensity (n=19) conditioning regimens were used. Of the 39 patients (78%) who survived for > or =28 days after transplant, 37 (95%) achieved neutrophil engraftment, while graft failure and rejection occurred in two of 39 (5%) and three of 37 (8%) patients, respectively. Stepwise Cox regression analysis revealed a significantly lower incidence of grades II-IV acute GVHD in patients receiving purified CD34+ cells (hazard ratio 0.32; 95% CI 0.12-0.84; P=0.022). By 1 year post transplant, 28 patients (56%) had died of transplant-related problems, including infectious complications (30%). Although the number of patients is small, our data suggest that transplant-related problems, particularly infectious complications, are major obstacles to the success of this therapy.

Adolescent↗

Clinical impact of graft-versus-host disease against leukemias not in remission at the time of allogeneic hematopoietic stem cell transplantation from related donors. The Japan Society for Hematopoietic Cell Transplantation Working Party.

Acute graft-versus-host disease (GVHD) increases post-transplant mortality and morbidity, but exerts a potent graft-versus-leukemia (GVL) effect. To clarify the impact of GVHD on outcome after transplant in aggressive diseases, patients with acute myeloid or lymphoblastic leukemia (AML, n = 366 or ALL, n = 255) in nonremission states, or chronic myelogenous leukemia (CML, n = 180) in accelerated phase (AP) or blastic crisis (BC), who received allogeneic hematopoietic stem cell transplantation (HSCT) from a related donor between 1991 and 2000, were analyzed. Significant improvement in overall and disease-free survival (DFS) was detected with grade I acute GVHD in AML (P = 0.0002 for overall survival and 0.0009 for DFS, respectively) and in CML (P = 0.0256 and 0.0366, respectively), while the trend towards improved survival was observed in ALL. Relapse rate was lower in grade I acute GVHD than in grade II in all three diseases, suggesting that treatment for grade II GVHD may compromise the GVL effect associated with GVHD. Chronic GVHD was found to suppress relapse in CML and ALL, but not in AML, although no improvement in survival was observed in any disease category. Our results suggest that treatment for grade II acute GVHD may need to be attenuated in transplant for refractory leukemias.

Adolescent↗

Dieulafoy's lesion of the esophagus correctly diagnosed and successfully treated by the endoscopic injection of N-butyl-2-cyanoacrylate.

Dieulafoy's lesion is an arterial malformation in the subumucosal layer of the gastrointestinal tract that can cause massive bleeding. The esophagus is not a common location for this lesion. We present here a first report of Dieulafoy's lesion of the esophagus correctly diagnosed and successfully treated by the endoscopic injection of N-butyl-2-cyanoacrylate.

Aged↗

Effects of growth hormone (GH) on mRNA levels of uncoupling proteins 1, 2, and 3 in brown and white adipose tissues and skeletal muscle in obese mice.

We have investigated whether GH treatment influences the expression of UCP1, 2 and 3 mRNA in a KK-Ay obese mouse model. KK-Ay mice (n = 10) and C57Bl/6J control mice (n = 10) were injected subcutaneously with human GH (1.0 mg/kg/day and 3.5 mg/kg/day) for 10 days, and compared with mice injected with physical saline. The KK-Ay obese mice weighed significantly less (p < 0.01 : 1.0 mg/kg/day, p < 0.05 : 3.5 mg/kg/day) and had smaller inguinal subcutaneous and perimetric white adipose tissue (WAT) pads (p < 0.05 : 3.5 mg/kg/day), but increased skeletal muscle weight (p < 0.05). The brown adipose tissue (BAT) weight did not change significantly. Not only plasma free fatty acid and glucose levels but also plasma insulin levels decreased. The reduced HOMA-IR (homeostasis model assessment-insulin resistance) values suggested that insulin resistance was improved by GH treatment. UCP1 mRNA levels increased after the 3.5 mg GH treatment by 2.8-fold (p < 0.01 vs. saline controls) and 2.0-fold (p < 0.05 vs. 1 mg GH treatment) in BAT, and by 6.0-fold in subcutaneous WAT (p < 0.05 vs. controls). UCP2 mRNA levels increased 2.2-fold (p < 0.05 vs. control) and 2.1-fold (p < 0.05 vs. 1 mg GH treatment) in BAT, and 2.0-fold (p < 0.05 vs. controls) in skeletal muscle. One mg GH administration also stimulated UCP1 mRNA expression by 2.5-fold (p < 0.05 vs. controls) and UCP3 mRNA expression by 2.8-fold (p < 0.05 vs. controls) in the muscle. On the other hand, lean mice showed no significant difference in body composition or plasma parameters. UCP1, 2 and 3 mRNA expression in lean mice did not show any significant change after treatment with GH. We conclude that GH treatment increased mRNA levels for not only UCP1, but also UCP 2 and 3 in BAT, WAT and muscle in a KK-Ay obese mouse model. These findings suggest that GH-induced thermogenesis may contribute to the reduction in WAT and energy expenditure.

Adipose Tissue↗

The clinical significance of Cyclin B1 and Wee1 expression in non-small-cell lung cancer.

BACKGROUND: Cyclin B1 has an important role in the G2-M phase transition of the cell cycle. Wee1 delays mitosis by suppressing the activity of the Cyclin B1/cdc2 complex. The objective of the present study was to elucidate the clinicopathological and prognostic significance of Cyclin B1 and Wee1 expression in non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: An immunohistochemical assessment of Cyclin B1 and Wee1 expression was performed in 79 patients with NSCLC. RESULTS: The expression of Cyclin B1 was correlated with differentiation (P = 0.0423) and vascular invasion (P = 0.001). Patients with overexpression of Cyclin B1 had higher mean values for both the Ki-67 proliferative index (Ki-Index) (P <0.0001) and proliferating cell nuclear antigen labeling index (PCNA-LI) (P <0.0001), and a poorer prognosis (P = 0.0068). Patients lacking expression of Wee1 had a higher recurrence rate (P = 0.0084) and a poorer prognosis (P = 0.0457), and tended to have higher Ki-Index and PCNA-LI values. Multivariate analysis suggested that both Cyclin B1 (P = 0.0244) and Wee1 (P = 0.0444) expression were significant prognostic factors. CONCLUSIONS: These findings suggest that Cyclin B1 expression could be a significant prognostic parameter in NSCLC. The loss of Wee1 expression may have a potential role in promoting tumor progression and may be a significant prognostic indicator in NSCLC.

Adult↗

Comparison between broilers and layers for growth and protein use by embryos.

Three experiments were conducted to compare the growth and protein utilization of embryo between broilers and layers. In experiments 1 and 2, the average weight of eggs was the same for broilers and layers. Nothing or an amino acid (AA) solution was injected into the eggs of broilers at d 7 of incubation, and the plasma AA concentration of newly hatched chicks was determined in broilers in experiment 1. In experiment 2, the same treatments as experiment 1 were used on layer breeder eggs. Plasma Tau, Thr, and Lys concentrations of hatched chicks increased when AA solution was injected in broilers breeder eggs (P < 0.05) but not in layers (P > 0.05). The AA ratio to Lys was reduced by AA injection in broilers but not in layers. In experiment 3, weights of embryos and egg were recorded, and CP contents were analyzed over time during incubation (d 0, 7, 14, and 19 of incubation) in broilers and layers using eggs of the same weight. There were no differences in the weights and CP contents of embryos and eggs from broilers and layers. On d 14 and 19 of incubation, weights and CP contents of embryo were higher in broilers than layers (P < 0.05). These results suggested that the egg protein content might be adequate for hatching but insufficient for maximum growth of embryos from broilers.

Amino Acids↗

Characteristics of the simulated workplace neutron fields using a 252Cf source surrounded with cylindrical moderators.

The authors established the simulated workplace neutron fields using a 252Cf source surrounded with cylindrical moderators at the Japan Nuclear Cycle Development Institute (JNC), Tokai Works. The moderators are annular cylinders made of polymethyl methacrylate and steel. The neutron energy spectrum at the reference calibration point was evaluated from the calculations by MCNP-4B and the measurements by the Bonner multisphere spectrometer and the hydrogen-filled proportional counters. The calculated neutron spectra were in good agreements with the measured ones. These fields can provide the realistic neutron spectra similar to those encountered around the glove-boxes of the fabrication process of MOX (PuO2-UO2 mixed oxide) fuel.

Body Burden↗