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M Tadokoro

Publications and source records attributed to M Tadokoro.

173 records · Page 10Linked to original sources
PubMedDate not supplied

Evaluation of thermoreversible gelation polymer for regeneration of focal liver injury.

Liver injuries are often associated with complications including infection of the dead space, bleeding, leakage of bile and so on. We have recently developed a thermoreversible gelation polymer (TGP) which provides a good healing environment for wounds and possibly reduces complications. The purpose of this study was to evaluate whether adequate regeneration occurred with a liver defect by using TGP. The sol-gel transition of TGP is reversibly controlled by temperature; TGP is soluble below a lower critical solution temperature (LCST) of 22 degrees C, and becomes solid above the LCST. Soluble TGP can reach anywhere, and gelation of TGP occurs at the wound surface by body temperature to fill the wound/cavity. A section of median part of the left lobe comprising 3% (2 x 2 cm wide and 1 cm deep) of the liver was resected, and the Beagle dogs were assigned to three groups: 'resection alone group', 'resection + fibrin glue (FG) group' and 'resection + TGP group'. The resection alone group and the resection + FG group showed severe fibrosis at week 12, and a scarring was clearly visible. The resection + TGP group showed almost complete healing by week 4, with no adhesion and recession of the wound; the resection site was completely filled with TGP, liver-like capsule organoids emerged to cover the wound and neovascularization was observed within the organoids. Furthermore, the resected liver regenerated completely by week 12, TGP was replaced by hepatocytes, and the presence of hepatic lobules confirmed structural reorganization. The number of RCA-1-positive macrophages accumulating around the wound was significantly reduced in the resection + TGP group compared to the other two groups. In the early stage of liver resection and regeneration, TGP seemed to suppress the accumulation of macrophages and stellate cells. In the late stage, when massive inflammatory cell accumulation had subsided, TGP was degraded, that may contribute to avoid unnecessary inhibition of the liver regeneration process. Collectively, TGP may induce efficient regeneration by reducing the fibrosis and enhancing proliferation, even with a minor liver defect. Because TGP has good biocompatibility, it may become useful as an ideal biomaterial for the treatment of liver injuries.

Acrylic Resins↗
PubMedDate not supplied

Papillary urothelial carcinoma of the urinary bladder demonstrating prominent signet-ring cells in a smear. A case report.

BACKGROUND: The appearance of numerous signetring cells (SRCs) without any other type of adenocarcinoma cells originating in papillary transitional cell carcinoma (TCC) in a urine smear is rare. CASE: The cytology from mucus-urine that was initially obtained by washing from a 69-year-old female revealed three different types of cells: (1) numerous single SRC carcinoma-type cells, (2) low grade TCC-type cells arranged in sheets, and (3) intermediate (transitional)-type cells with both aspects of TCC and adenocarcinoma (SRC carcinoma) and mucus in the background. The latter two cell populations were retrospectively confirmed after histologic diagnosis of a primary papillary TCC with glandular differentiation. CONCLUSION: One should keep in mind that even a low grade papillary TCC with glandular differentiation of the bladder can exhibit excessive SRC-type cells in urine.

Aged↗
PubMedDate not supplied

Primary squamous cell carcinoma of the liver: a case report.

BACKGROUND: Bile cytology from percutaneous transhepatic cholangio-drainage (PTCD) is a useful procedure in case of obstructive jaundice. CASE: Repeated cytology via PTCD from a cystically dilated duct in a 56-year-old female with a long clinical history permitted a diagnosis of squamous cell carcinoma (SCC). The smears showed excessive benign-appearing squamous cells with or without a nucleus and a few keratinized- and nonkeratinized-type SCC cells. No adenocarcinoma-derived cells were identified. No focus of SCC was detected clinically. The resected hepatic specimen disclosed a keratinized-type SCC simultaneous with benign metaplastic squamous epithelium. CONCLUSION: This case of cytology of primary SCC of the liver seems to be the first reported. Even when showing a great number of benign-appearing squamous cells, the possibility of malignancy should not be ruled out. Repeating the cytology from PTCD is effective for a diagnosis.

Carcinoma, Squamous Cell↗
PubMedDate not supplied

Interactive fusion of three-dimensional images of upper abdominal CT and FDG PET with no body surface markers.

The aim of this study was to propose and validate a new method of making fused images from CT and FDG PET images for the upper abdominal area with no body surface marker. PET and CT were carried out in patients with pancreatic cancer (N = 5) and mass-forming pancreatitis (N = 2). First, we determined the midsagittal plane from PET and CT data. From the difference in location of the midsagittal planes, rotations of Y (from back to front) and Z axes (from foot to head) and X translation (from right to left) were calculated. An upper pole of the kidney was determined from PET and CT data. It showed Y and Z translations. The images of the three-dimensional data sets were fused on a workstation. Reproducibility was assessed with randomly misaligned PET and CT data sets. Pancreatic cancer and its lymph node metastases were identified easily on fused images. In reproducibility assessment, the average error of rotation was 0.77 degree. The average errors of translation were 3.43, 4.70, and 9.23 mm on the X, Y, and Z axes, respectively. In conclusion, this PET/CT image registration technique is feasible and practical. It allows precise anatomical assessment of normal and abnormal FDG accumulation.

Aged↗
PubMedDate not supplied

Multi-directional positron imaging: evaluation of cancer detection with 2-(F-18)-fluoro-2-deoxy-D-glucose.

We developed a multi-directional positron imaging system for the whole body in order to evaluate the spatial distribution of radiopharmaceuticals. A positron emission tomography (PET) scanner with ring detectors was modified to provide 54 directional planar images with a three-dimensional appearance by using cinematic display. The initial clinical evaluation was performed on two normal volunteers and 17 cancer patients with 32 foci. Images were obtained approximately one hour after the intravenous administration of 2-(F-18)-fluoro-2-deoxy-D-glucose. In all 19 subjects, good quality images with a three-dimensional appearance were obtained. We were able to visualize 16 of 20 (80%) lesions that were three centimeters or more in greatest diameter. In contrast, only seven of 12 (58%) lesions less than three centimeters in greatest diameter were identified. The overall detectability of lesions was 72%. These results suggest that this system will be useful for tumor detection.

Aged↗
PubMedDate not supplied

Asymmetrical FDG-PET and MRI findings of striatonigral system in multiple system atrophy with hemiparkinsonism.

The asymmetry of the local cerebral metabolic rate for glucose (lCMRglc) and magnetic resonance (MR) imaging was studied in five patients with multiple system atrophy (MSA) presenting hemiparkinsonism. lCMRglc was measured with 18F-2-fluoro-2-deoxy-D-glucose and positron emission tomography (PET) in these patients and five normal control subjects. MR images were obtained in five patients and 11 control subjects. In all patients, T2-weighted MR images showed hypointense areas in the posterior lateral putamen. They were bigger or lower in intensity on the contralateral side than on the ipsilateral side. Significant glucose hypometabolism was found in the posterior putamen on the contralateral side to hemiparkinsonism. A significant decrease in size was found in the contralateral putamen, caudate nucleus, and pars compacta of the substantia nigra. However, no significant correlation was seen between PET and MRI data. In the control subjects, no apparent asymmetry was observed. PET and MR imaging demonstrated the characteristic asymmetry corresponding to the pathological findings reported in MSA.

Brain↗
PubMedDate not supplied

Aspiration biopsy cytology of secretory carcinoma of the breast. A case report.

Secretory carcinoma diagnosed by aspiration biopsy cytology (ABC) disclosed many characteristic figures that were similar to a bunch of grapes, secondary mucous globular structures (MGSs) and clustered MGSs. The MGS was a unit structure of secretory carcinoma composed of a centrally located, small amount of mucus and two or more tumor cells covering it. Other findings were vacuolated cells and mucus in a clear background. The presence of the above findings, especially the "bunch of grapes" and related forms, were though to be essential findings in the cytologic differential diagnosis of secretory carcinoma by the ABC method. The origin of the characteristic features is discussed.

Adult↗
PubMedDate not supplied

Evaluation of the performance of a whole-body positron imaging system with attenuation correction.

A PET scanner with ring detectors has been modified to accomplish whole-body imaging with attenuation correction. To evaluate the performance of this system, phantom studies and clinical studies were performed in seven patients. The transaxial resolution (FWHM) at the center of the field was 8.6 mm, and the axial resolution was 12.3 mm. The counts on the images with attenuation correction were linearly related to accumulation of the radiopharmaceuticals, and attenuation correction was made accurately. The transmission scan from the top of the head to the thigh, about 110 cm in length, required 36 minutes, and one emission scan required 18 minutes. The total study time for one transmission scan and three sequential emission scans was 1.9 hours. In clinical studies, attenuation correction made the discrimination of organs clearer, and would facilitate the detection of tumors, especially those in the high attenuation organs or matter. The use of this system made it possible to obtain quantitative whole-body positron images with adequate diagnostic quality within a reasonable scanning time.

Aged↗
PubMedDate not supplied

Secretory carcinoma of the breast. Correlation of aspiration cytology and histology.

We analyzed the fine needle aspiration findings in five cases of secretory carcinoma of the breast in adults to clarify their cytomorphologic features and correlate them with their histology. The cytologic smears revealed grapelike clusters of mucous globular structures (MGSs); single MGSs; clusters and sheets of cells with pale green and slightly granular cytoplasm with or without intracytoplasmic vacuolization; some ordinary duct carcinoma-like arrangements; scattered, single, vacuolated cells; some extracellular mucus; and a clean background. The MGSs were globular structures consisting of distinctive vacuolated cells containing large globules of a secretory product. The cytologic findings showed a similar wide variation in the range of histologic appearances; however, the grapelike clusters of MGSs, which corresponded to a microcystic or microfollicular pattern histologically, were present in most cases and should suggest a diagnosis of secretory carcinoma.

Adult↗
PubMedDate not supplied

Fine needle aspiration cytology of lipid-secreting carcinoma of the breast. A case report.

Fine needle aspiration (FNA) cytology of lipid-secreting carcinoma of the breast was performed on a 43-year-old woman who was admitted with a left breast tumor. Smears of the aspirate showed atypical cells that contained numerous large and small vacuoles in the cytoplasm and were diagnosed as adenocarcinoma of the breast. A modified radical mastectomy was performed under the diagnosis of breast carcinoma. A solid, yellowish, milky white, well-demarcated tumor was found in the resected specimen. Microscopically, hematoxylin and eosin staining revealed foamy and granular vacuoles in the cytoplasm of the tumor cells similar to those seen on the smears, which were positive for lipid staining. Electron microscopic examination also showed numerous intracytoplasmic lipid droplets in the tumor cells. This tumor was finally diagnosed as lipid-secreting carcinoma of the breast on the basis of histologic and electron microscopic features. Lipid-secreting carcinoma of the breast is rare, and only one recurrent case diagnosed by cytology in pleural and pericardial fluids has been described. Since the tumor cells originating in lipid-secreting carcinoma of the breast differ from ordinary breast carcinoma cells, FNA cytology is useful in diagnosing this neoplasm.

Adult↗