Biomedical subjects

Hirotaka Sato

Publications and source records attributed to Hirotaka Sato.

9 recordsLinked to original sources

PubMed2006

Abnormal collateral arterial systems in Takayasu's arteritis and Leriche's syndrome evaluated by whole body acquisition using multislice computed tomography.

Takayasu's arteritis causes various arterial changes, including wall thickening, occlusion, aneurysm, and calcification. Similarly, Leriche's syndrome causes occlusion of the abdominal aorta or iliac arteries accompanied by ischemic symptoms of the distal lower extremities. Both diseases are potentially associated with the development of unexpected collateral arteries throughout the body. We evaluated whole body arteries in subjects with Takayasu's arteritis and Leriche's syndrome using 16-slice multislice CT and concluded that it was a useful tool to detect unexpected collateral arterial systems in Takayasu's arteritis or Leriche's syndrome in a non-invasive fashion.

Aged↗

PubMed2006

Fluorescence in situ hybridization analysis of c-myc amplification in stage TNM prostate cancer in Japanese patients.

OBJECTIVE: Genetic aberration such as the amplification of c-myc has been commonly found in advanced prostate cancer. The aim of this study was to elucidate chromosome 8 alteration, including a gain and amplification of 8q24 (c-myc gene), related to the progression and survival in advanced (Stage C) prostate cancer. MATERIALS AND METHODS: We used dual-probe fluorescence in situ hybridization with a centromere-specific probe for chromosome 8 (8cen), and with a region-specific probe for c-myc (8q24) to evaluate genetic changes in tumor samples from 50 patients who had undergone radical retropubic prostatectomy from 1986 to 2001. RESULTS: We classified the 8cen and c-myc copy numbers as normal, gain and amplification. The carcinoma foci with extra copies of c-myc, which was defined in 35 cases (70%), were divided into two groups: (a) a simple gain of the whole chromosome 8 (no increase in the c-myc copy number relative to the chromosome 8 centromere), which was identified in 15 cases (30%); and (b) a substantial amplification of c-myc (additional increases [AI] in the c-myc copy number relative to the chromosome 8 centromere), which was detected in 20 cases (40%). AI-c-myc was strongly associated with higher histopathological grades and Gleason's scores (P = 0.0330, 0.0190, respectively). Patients with the AI-c-myc had earlier disease progression (P = 0.0029) and earlier cancer death (P = 0.0087) than did patients with normal patterns. CONCLUSION: Identification of an AI-c-myc may serve as a potential marker of prostate cancer progression.

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PubMed2006

[Analysis by structural equation modeling of the questionnaire about the risk and its preventive measures in a pharmacy].

Pharmacists are now facing a problem of developing measures for dispensing mistakes, because there recently is increasing social awareness on medical accidents and a tendency to increase medical accidents in pharmacies due to popularizing separation of dispensing and prescribing functions. In this study, questionnaire survey was conducted to investigate pharmacist's views on human error measures and the relationship between mistakes and the preventive measures. To clarify relationship between human error measures and preventive measures for avoiding mistakes, questionnaire result was analyzed based on structural equation modeling (SEM). Questionnaire survey was sent to community pharmacies in Hokkaido. The result was analyzed by SEM. The recovery rate of the questionnaire was 71.0%. Human error measures were classified into "The measures against deficient knowledge and insufficient experiences". "Attention problem measures" and "The measures against a cognitive error". While attention problem was strongly related to the cognitive error, there was no relationship between "Attention problem measures" and "The measures against a cognitive error". Moreover, it were clarified that to develop human error measures for deficient knowledge and insufficient experiences was effective for the preventive against the mismatch of the cognitive mechanism and the intentional mistake and for bridging the gap between knowledge and experiences. This study showed that SEM was effective for adopting efficient preventive measures for medical accident and analyzing risk management in pharmacies. Applying these results to the medical accident preventive measures contribute to improvement of the risk management.

Humans↗

PubMed2005

Utility of triple channel injection of contrast material with mixture of saline, with acquisition in the cephalic direction for arterial trees in the thorax using multislice computed tomography.

BACKGROUND: If contrast material is injected into the cubital vein, artifacts due to high concentration of the contrast material in the vein lead to deterioration of the opacification of the thoracic aorta and the major branches. We describe a new protocol employing a combination of triple channel contrast material injection and a mixture of saline with acquisition in the cephalic direction utilizing capability of 16-slice multislice CT. MATERIALS AND METHODS: Of 35 subjects who underwent thoracic CT, 18 were injected with 70 ml contrast each prior to scanning with acquisition in the cephalic direction during the injection of 30 ml contrast diluted 50/50 with saline, followed by the injection of 20 ml of saline (new protocol). Seventeen subjects were injected each with 100 ml contrast at 3 ml/s, with scanning in the caudal direction (ordinary protocol). RESULTS: In the new protocol, the major branches of the aorta and the left ventricle were more opacified, but the veins were less opacified compared with the ordinary protocol, resulting in clear delineation of the thoracic aorta and the major branches without artifacts. CONCLUSIONS: A new acquisition protocol is described in which the thoracic aorta and the major branches can be evaluated without artifact due to high CT values in the veins. Faster, more informative CT scans can be performed using diluted contrast.

Contrast Media↗

PubMed2005

High efficiency electrochemical immuno sensors using 3D comb electrodes.

To realize highly sensitive electrochemical immunoassays, a micro-fabricated three-dimensional (3D) electrode was fabricated and applied to enzyme immuno assay based on production of a redox species. The dimensions of the electrodes are 10 microm in width and 30 microm in height, with 20 microm spacing in between, and the 30 pairs of anode and cathode electrodes made up a single sensor. This structure lead to enhancement of the electrochemical reaction, nearly 100% of trap ratio of redox species. It can be applied to highly sensitive enzyme immuno sensing based on p-aminophenylphosphate (PAPP). Applicability of this technique to the immuno assay for one of the clinical diagnostic marker proteins (alpha-fetoprotein; AFP) from 6 to 500 ng/mL was demonstrated.

Biological Assay↗

PubMed2005

Area-selective formation of macropore array by anisotropic electrochemical etching on an n-Si(100) surface in aqueous HF solution.

A photoassisted anodization process to fabricate arrays of uniform and straight macropores at selected areas of a Si wafer surface was developed. The front- and backside surfaces of n-type Si(100) wafers were coated with a thin Si(3)N(4) layer, and the frontside layer was micro-patterned using photolithography and reactive ion etching to form an array of microscopic openings at selected areas. The inverted pyramid-shape micropits were formed at these openings by anisotropic etching using aqueous KOH solution; these pits act as the initiation sites for the anodization to form macropores. The electrochemical etching was carried out in aqueous HF solution under illumination from the backside of the wafer, on which Au/Cr electric contact was formed following removal of the Si(3)N(4) layer. To improve the uniformity of the formation condition of the macropores at the selected area, holes were area-selectively generated by controlling the illumination condition during the anodization. For this, micropatterns were formed on the Au/Cr layer at the backside surface, which were aligned to those at the frontside surface. The parameters, such as HF concentration, current density, and wafer thickness, i.e., hole diffusion length, were optimized, and the arrays of uniform and high-aspect-ratio macropores were formed at the selected area of the domain at the silicon surface.

Journal Article↗

PubMed2004

Multicentric liposarcoma.

Abstract A 72-year-old man complaining of upper abdominal discomfort was diagnosed as having retroperitoneal liposarcoma by means of diagnostic imaging. He then underwent an operation. One mass existed on the curvatura ventriculi major, extending to the hilum splenicum and pressing back the pancreal head and body. There was another mass to the left of the first, situated on the ventral side of the left kidney. Also, another mass was intramurally found adjacent to the curvatura ventriculi major. Histologically, the mass on the curvatura ventriculi major ranged from the peritoneal cavity to the retroperitoneum Its intraperitoneal portion was classified as a differentiated lipoma-like type and the retroperitoneal mass was of mucous type. The mass on the left kidney was of a differentiated fibrosing type. The intramural mass in the gastric curvature was found to be a differentiated lipoma-like type. The patient has been under observation for 12 months and has shown no recurrence.

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PubMed2002

Expression of the endothelial receptor tyrosine kinase Tie2 in lobular capillary hemangioma of the oral mucosa: an immunohistochemical study.

BACKGROUND: Lobular capillary hemangioma (LCH) usually occurs in the skin or mucous membranes as a rapidly growing red nodule. LCH is one of the most common vascular lesions in the oral mucosa. Tie2 is a novel, human endothelial receptor tyrosine kinase which may play an important role in blood vessel formation. In this study, we investigated its immunohistochemical expression in LCH of the oral mucosa. METHODS: Double immunostaining with anti-CD34 and antialpha smooth muscle actin (SMA) antibodies was performed to characterize the cellular expression of Tie2 in 15 cases of this condition. RESULTS: We found Tie2 immunoreactivity in the ovoid cells only, which were frequently intermingled with alphaSMA-positive cells, especially in the hypercellular portion of LCH. CONCLUSIONS: These results suggest that the expression of Tie2 in ovoid cells and the interaction between ovoid cells and alphaSMA-positive cells play an important part in the development and progression of LCH.

Actins↗

PubMed2002

Combined tumor consisting of non-functioning adrenocortical adenoma and pheochromocytoma in the same gland.

A 59-year-old woman was admitted to East Tokyo Metropolitan Hospital for further examination of a left adrenal mass. Catecholamine levels in the plasma and urine were within normal limits. Neither (131)I-metaiodobenzylguanidine (MIBG) nor norcholestenol iodomethyl ((131)I) had accumulated in the left adrenal gland. A left adrenalectomy was performed through a retroperitoneal endoscope. Sections showed a tumor consisting of two parts. Histologically one part of the tumor was completely encapsulated, with clear cells comprising a honeycomb-like mass, regarded as adrenocortical adenoma. The other part consisted of rich cytoplasma and these basophilic, hyperchromatic cells included alveolar patterns, resulting in the diagnosis of pheochromocytoma. Thus, an extremely rare case of non-functioning adrenal incidentaloma consisting of an adrenocortical adenoma and a concomitant pheochromocytoma in the same gland is reported here.

Adrenal Gland Neoplasms↗