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1.
Kayoko Minakata Masako Suzuki Hideki Nozawa Kunio Gonmori Kanako Watanabe Osamu Suzuki 《Forensic Toxicology》2006,24(2):83-87
Platinum (Pt) levels were determined in various tissues and body fluids obtained from a patient who died 181 days after cisplatin
overdosing. The symptoms of cisplatin overdose, however, might have almost disappeared by day 40, and the patient’s death
was ascribed to the recurrence of malignant lymphoma. Determination of Pt derived from cisplatin was performed by electrospray
ionization mass spectrometry (ESI-MS) using silver (Ag) as internal standard. Pt and Ag complexed with diethyldithiocarbamate
(DDC) in wetashed blood, and tissue solutions were extracted into isoamyl alcohol, and then acidified with oxalic acid. By
injecting an aliquot of the isoamyl alcohol layer into a mass spectrometer in the direct flow injection mode, the quantitation
was performed using the signals of Pt(DDC)3
+ and Ag(DDC)2
+ at m/z 639 and 403, respectively. The Pt levels ranged from 25ng/ml in blood to 2050ng/g wet weight in the liver of the patient,
indicating that Pt remained at high levels in tissues, even after a period as long as 181 days after cisplatin overdosing. 相似文献
2.
Yongkang Nie Qiang Li Feng Li Yonglin Pu Daniel Appelbaum Kunio Doi 《Journal of nuclear medicine》2006,47(7):1075-1080
Our objective was to develop and evaluate 3 semiautomatic computer-aided diagnostic (CAD) schemes for distinguishing between benign and malignant pulmonary nodules by use of features extracted from CT, 18F-FDG PET, and both CT and 18F-FDG PET. METHODS: We retrospectively collected 92 consecutive cases of pulmonary nodules (<3 cm) in patients who underwent both thoracic CT and whole-body PET/CT. Forty-two of the nodules were malignant and 50 benign, as confirmed by pathologic examination and clinical follow-up. The interval between CT and PET was less than 1 mo. Four clinical parameters, including patient age, sex, smoking status, and history of previous malignancy, were used for the CAD schemes. Sixteen CT features based on size, shape, margin, and internal structure of nodules were independently rated subjectively by 2 chest radiologists. Four PET features were viewed on a PET/CT workstation. CAD schemes based on clinical parameters together with CT features, PET features, and both CT and PET features were then used to differentiate benign from malignant nodules. Finally, the output from the CAD schemes was evaluated by use of receiver-operating-characteristic analysis. RESULTS: When we used clinical parameters and CT features as input units (CAD scheme 1), the area under the receiver-operating-characteristic curve (A(z) value) of the CAD scheme was 0.83. When we used clinical parameters and PET features as input units (CAD scheme 2), the A(z) value for the computer output was 0.91. However, when we used all data as input units (CAD scheme 3), the A(z) value for the computer output was 0.95. The performance of CAD scheme 3 was better than that of CAD scheme 1 or 2. A statistically significant difference existed between the A(z) values of CAD schemes 3 and 2 (P = 0.037) and between those of CAD schemes 3 and 1 (P = 0.015). CONCLUSION: Our CAD scheme based on both PET and CT was better able to differentiate benign from malignant pulmonary nodules than were the CAD schemes based on PET alone and CT alone. 相似文献
3.
Hiroki Otani Yutaka Kagaya Yoshio Imahori Satoshi Yasuda Ryo Fujii Masanobu Chida Shigeto Namiuchi Morihiko Takeda Masahito Sakuma Jun Watanabe Tatsuo Ido Hiroshi Nonogi Kunio Shirato 《Journal of nuclear medicine》2005,46(4):553-559
Left ventricular (LV) remodeling after myocardial infarction (MI) is a maladaptive process that increases the risk of heart failure and death. The myocardial phosphoinositide cycle, which is located downstream from several neurohumoral factors, plays a crucial role in LV remodeling. Our animal studies demonstrated that 1-[1-11C]butyryl-2-palmitoyl-rac-glycerol (11C-DAG) can be used to visualize regions with an activated phosphoinositide cycle. Therefore, we examined whether myocardial 11C-DAG accumulation assessed by PET is relevant to LV enlargement and systolic dysfunction in post-MI patients. METHODS: We performed PET with 11C-DAG in 13 post-anteroseptal MI patients and 4 healthy volunteers. We placed regions of interest on the noninfarcted myocardium and calculated the myocardium-to-left atrial (LA) chamber ratio of 11C-DAG accumulation. RESULTS: The myocardium-to-LA chamber ratio of 11C-DAG was significantly higher in the post-MI patients (mean +/- SD, 1.73 +/- 0.35) compared with that of the healthy volunteers (mean +/- SD, 1.25 +/- 0.13; P < 0.05). In the post-MI patients, the myocardium-to-LA chamber ratio of (11)C-DAG was significantly correlated with the LV end-diastolic volume index (r = 0.79, P < 0.01) and the plasma concentration of brain natriuretic peptide (r = 0.85, P < 0.001) and negatively correlated with the LV ejection fraction (r = -0.69, P < 0.01). CONCLUSION: These findings suggest that the myocardial 11C-DAG accumulation assessed by PET is relevant to LV enlargement, LV systolic dysfunction, and humoral activation in post-MI patients. This new imaging strategy based on intracellular signaling may contribute to the assessment and treatment of post-MI patients. 相似文献
4.
5.
Yoichiro Hosokawa D.D.S. D.D.Sc. Kazuyuki Minowa D.D.S. Satoru Abe M.D. Keiichi Ohmori D.D.S. D.D.Sc. Michio Yamasaki M.D. D.M.Sc. Masanobu Shindoh D.D.S. D.D.Sc. Tadashi Iizuka D.D.S. D.D.Sc. Mohiuddin Ahmed B.D.S. Akira Amemiya D.D.S. D.D.Sc. 《Oral Radiology》1991,7(1):1-6
A case of an odontogenic tumor which invaded the intracranial space from the mandible is reported. Judging from the radiographic
images it was similar to a malignant tumor. The patient died 17 years after the first visit. According to the final pathological
diagnosis, it was malignant odontogenic mixed tumor of low grade which did not belong to any of the WHO classification. 相似文献
6.
The effect of the hepatic energy status on the development of posttraumatic jaundice (PTJ) was studied to clarify the mechanism of PTJ. Fifty-four patients with severe torso injury who were expected to develop PTJ on admission with an average Injury Severity Score of 27 were selected for this study. They were retrospectively divided into three groups according to their maximum bilirubin concentration by day 10: group H, 12 patients with marked elevation of serum bilirubin (>8 g/dl); group L, 23 with mild bilirubinemia (2–8 g/dl); and group N, 19 with no bilirubinemia (<2 g/dl). Group H patients, in whom trauma-related shock was severe and prolonged, developed severe hyperbilirubinemia, and their arterial ketone body ratio (AKBR), which reflects the hepatic mitochondrial redox state and is closely correlated to its energy production, was significantly lower throughout the first week. In contrast, the AKBR increased to an above normal level, indicating enhanced energy production in groups N and L. The serum direct/total bilirubin was also higher in group H. The abnormal hepatic energy metabolism is considered to have reduced the excretion of conjugated bilirubin from the hepatocytes into the bile canaliculi, which is a process that has to proceed against the bilirubin concentration gradient. The subsequent diffusion of the accumulated water-soluble conjugated bilirubin in hepatocytes into the blood is thus considered to be one of the causes of PTJ. 相似文献
7.
T. Onishi T. Machida N. Iizuka K. Nakauchi H. Shirakawa F. Masuda S. Mochizuki H. Tsukamoto N. Harada 《Urological research》1990,18(5):313-318
Summary Utilizing two types of human renal carcinoma heterotransplanted in nude mice, we investigated the variations in hyperthermic effects (42.5°C for 30 min) caused by differences in tumor type with special reference to variations in tumor vascularity. In the hypovascular JRC1 strain, sporadic vascular dilation was observed throughout the tumors after heating. Destruction of tumor cells was observed mainly in the region of dilation. In the hypervascular JRC11 strain, homogenous vascular dilation was observed immediately after heating, mainly at the periphery of tumors. There was a decrease in the viability of cells in the center of the tumor. Therefore, the hypervascular tumors showed greater destruction mainly at the center where blood circulation was reduced. The range of necrosis was also greatly affected by the extent of vascular dilation caused by heating in hypovascular tumors. 相似文献
8.
Gliomatosis cerebri with good prognosis 总被引:4,自引:0,他引:4
Seiji Kannuki Hideki Hondo Kunio Ii Takanori Hirose Keizo Matsumoto 《Brain tumor pathology》1997,14(1):53-57
A 52-year-old man was admitted to our clinic with severe headache and bilateral papilledema. Magnetic resonance (MR) images
on admission demonstrated diffuse swelling of the cerebral cortex without formation of a tumor mass. Biopsy revealed diffuse
infiltration with neoplastic glial cells. After radiation and chemotherapy, the MR images returned to normal. The morphological
and neurological features of the present case met the criteria for gliomatosis cerebri. However, this patient showed an unusually
good response to radiation and chemotherapy. 相似文献
9.
10.
Kazutoshi Hori Kunio Uematsu Hitoshi Yasoshima Aklhiko Yamada Kazunari Sakurai Munehiko Ohya 《Pathology international》1997,47(9):592-599
Testicular seminoma with elevated serum human chorionic gonadotropin level (hCG-positive seminoma) is regarded as more malignant than marker-negative seminoma, although Its prognosis is still unclear. To clarify the malignant potential of seminoma with hCG production, the serum levels of the beta subunit of hCG (β-hCG) and lactic acid dehydrogenase (LDH) were examined in 35 and 40 patients, respectively, and the Immunohistochemical expression of β-hCG examined in 45 tumors. The elevation of the LDH serum level correlated to the Invasive status, metestatic status and poor outcome, while that of the serum β-hCG level correlated only to the metastatic status. Immunohistochemical expression of β-hCG was observed in syncytiotrophoblastic giant cells in 11 tumors and a few mononuclear seminoma cells In 36 tumors. Expression was not associated with the malignancy potential, except where the expression In mononuclear cells Inversely correlated to the invasive status. These results suggest that most seminomas produce a slight amount of hCG; that an elevated hCG serum level Indicates the pressnce of metastatic tumors and mainly reflects an increase in tumor volume but not in cellular malignancy potential; and that the LDH serum level, rather than hCG, is more useful as a prognostic indicator for patients with seminoma. 相似文献