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51.
52.
Matsukuma S Eishi K Yamachika S Hayashi T Hazama S Yamaguchi H Ariyoshi T Takai H Odate T Onohara D Yanatori M 《The Annals of thoracic surgery》2005,80(6):2364-2365
A 54-year-old male who experienced a syncopal episode underwent aortic valve replacement for aortic stenosis and regurgitation. The aortic valve was incompetent as a result of thickening of the left coronary cusp and noncoronary cusp. In addition a saccular aneurysm was indicated on the left coronary cusp. A shelf of tissue protruding at right angles from the ventricular septum was particularly prominent below the right coronary cusp, resulting in subvalvular stenosis. The cause of the saccular aneurysm was most likely caused by the long-term effects of the jet stream instigated by discrete subaortic stenosis. 相似文献
53.
K Kusuzaki F Yamashita K Sakakida M Kamachi T Ashihara 《Nippon Seikeigeka Gakkai zasshi》1983,57(7):721-727
There have been no reported studies on the Feulgen-DNA cytofluorometry of the cartilage cells. We have attempted to devise a method of cell separation from the epiphyseal and articular cartilages of the rats, and to analyze by cytofluorometry the changes in the ploidy patterns of these chondrocytes during growth and ageing of the animals. Chondrocytes were isolated from the proximal cartilage of tibia by dual enzymatic digestions of the cartilage matrix with papain and collagenase, followed by mechanical cell separation with scissors and a micro-homogenizer, and were smeared onto the object glass with PBS. These procedures were found to be suitable for the Feulgen-DNA cytofluorometry of the chondrocytes from our repeated studies. We also carried out Feulgen-DNA cytofluorometry combined with 3H-thymidine autoradiography to determine cellular DNA content of the DNA synthetic chondrocytes in the epiphyseal cartilage. It has been clarified that during the growth course of the rats, the chondrocytes of the epiphyseal cartilage consist of many mononuclear diploid cells, a few mononuclear tetraploid cells and of some fraction of the cells having intermediate DNA values between the diploid and tetraploid levels. Those cells with intermediate DNA values, after autoradiographic studies, were found to correspond to DNA synthetic cells, indicating cell proliferative activity. It has been shown that during ageing of the rats, most of the chondrocytes from the articular cartilage are mononuclear diploid cells. The distribution of each cellular DNA content at the diploid level as determined by Feulgen-DNA cytofluorometry was shown to become gradually broader. 相似文献
54.
55.
Kagawa K Chugani DC Asano E Juhász C Muzik O Shah A Shah J Sood S Kupsky WJ Mangner TJ Chakraborty PK Chugani HT 《Journal of child neurology》2005,20(5):429-438
Tuberous sclerosis complex is commonly associated with medically intractable seizures. We previously demonstrated that high uptake of alpha-[11C]methyl-L-tryptophan (AMT) on positron emission tomography (PET) occurs in a subset of epileptogenic tubers consistent with the location of seizure focus. In the present study, we analyzed the surgical outcome of children with tuberous sclerosis complex in relation to AMT PET results. Seventeen children (mean age 4.7 years) underwent epilepsy surgery, guided by long-term videoelectroencephalography (EEG) (including intracranial EEG in 14 cases), magnetic resonance imaging (MRI), and AMT PET. AMT uptake values of cortical tubers were measured using regions of interest delineated on coregistered MRI and were divided by the value for normal-appearing cortex to obtain an AMT uptake ratio. Based on surgical outcome data, tubers showing increased AMT uptake (uptake ratio greater than 1.00) were classified into three categories: (1) epileptogenic (tubers within an EEG-defined epileptic focus whose resection resulted in seizure-free outcome), (2) nonepileptogenic (tubers that were not resected but the patient became seizure free), or (3) uncertain (all other tubers). Increased AMT uptake was found in 30 tubers of 16 children, and 23 of these tubers (77%) were located in an EEG-defined epileptic focus. The tuber with the highest uptake was located in an ictal EEG onset region in each patient. Increased AMT uptake indicated an epileptic region not suspected by scalp EEG in four cases. Twelve children (71%) achieved seizure-free outcome (median follow-up 15 months). Based on outcome criteria, 19 of 30 tubers (63%) with increased AMT uptake were epileptogenic, and these tubers had significantly higher AMT uptake than the nonepileptogenic ones (P = .009). Tubers with at least 10% increase of AMT uptake (in nine patients) were all epileptogenic. Using a cutoff threshold of 1.02 for AMT uptake ratio provided an optimal accuracy of 83% for detecting tubers that needed to be resected to achieve a seizure-free outcome. The findings suggest that resection of tubers with increased AMT uptake is highly desirable to achieve seizure-free surgical outcome in children with tuberous sclerosis complex and intractable epilepsy. AMT PET can provide independent complementary information regarding the localization of epileptogenic regions in tuberous sclerosis complex and enhance the confidence of patient selection for successful epilepsy surgery. 相似文献
56.
OBJECTIVE: Collagen gel constitutes a valuable tool for the study of cell-matrix interactions; however, it is sometimes difficult to use the gel, in which tumor and stromal cells are cocultured, for immunohistochemistry, because it is easily broken during the process of fixation and embedding in paraffin, especially after long-term culture. METHODS: To examine the interaction between endometrial cancer cells and fibroblasts in tumor invasion, we carried out three-dimensional (3-D) coculture of various endometrial cancer cell lines and fibroblasts in human placenta derived collagen sponges and analyzed the expression and localization of matrix metalloproteinases (MMP) and plasminogen activators (PA) in these cells by immunohistochemistry. RESULTS: After 4 weeks of culture on the collagen sponges, endometrial cancer cells composed stratiform or glandular structures on the layer of extracellular matrix, which was composed from fibloblasts and extracellular matrix. Compared to Ishikawa cells, which were rarely invasive, HEC-1A and HEC-1BE and cocultured fibroblasts showed high invasiveness and strong expression of some proteins. In cell line HEC-1BE, MMP-1, -7, and -9, MT1-MMP, tissue inhibitors of metalloproteinases 2, and uPA showed intensive staining in both cancer cells and fibroblasts by immunohistochemistry. HEC-1A cells and cocultured fibroblasts showed expression patterns similar to those of HEC-1BE. CONCLUSION: These results suggested that expression of MMPs and uPA was accelerated in fibroblasts surrounded by cancer cells. We believe that our 3-D coculture system has merit in that the interaction between cancer cells and stromal cells can be visually analyzed by immunohistochemistry and that experiments for a long period, at least 2 weeks, are possible. Furthermore, it is expected that some animal, e.g., nude mouse, experiments can be replaced by experiments using this culture system. 相似文献
57.
Eishi Y 《Nihon rinsho. Japanese journal of clinical medicine》2002,60(9):1688-1696
The cause(s) of sarcoidosis is unknown. Sarcoidosis seems to result from exposure of a genetically susceptible subject to a specific environmental antigen(s). From biopsy samples of lymph nodes from patients with sarcoidosis, Propionibacterium acnes has been isolated in culture, and many genomes of P.acnes or P.granulosum have been detected by quantitative PCR. Antigen-specific mitogenic responses of peripheral blood mononuclear cells were induced in sarcoidosis patients but not in healthy controls, when recombinant proteins from a propionibacterial trigger factor were used as stimulators. Sarcoidosis may arise from a Th1 immune response to one or more antigens of propionibacteria in an individual with a hereditary or acquired abnormality of the immune system. 相似文献
58.
Qian LW Mizumoto K Maehara N Ohuchida K Inadome N Saimura M Nagai E Matsumoto K Nakamura T Tanaka M 《Cancer letters》2003,190(1):105-112
The intensive stromal reaction is one of characteristics of pancreatic exocrine carcinoma. The mutual interaction between pancreatic cancer cells and orthotopic tumor-derived fibroblasts have not been clarified yet. In this study, we sought to elucidate the mechanism underlying the tumor-stromal interaction with an in vitro coculture experimental system. Considerable strong c-Met expression was detected in seven out ten lines of human pancreatic carcinoma cells, as determined by Western blotting. For hepatocyte growth factor (HGF)-production, however, none or only trace amounts of HGF could be detected in those ten cell lines. Of the two lots of tumor-derived fibroblasts obtained from two pancreatic cancer patients, the fibroblasts capable to produce HGF could initiate an apparent invasion-stimulating response in strong c-Met-expressed Suit-2 and Panc-1 cells but not in faint expressed Mia PaCa-2 and BxPC-3 cells. A specialized HGF antagonist, NK4 would effectively inhibit the fibroblast-mediated invasive growth, thus proving the key role of the paracrine-fashioned HGF/c-Met pathway in the tumor-stromal interaction. On the other hand, the regulative action of cancer cells on HGF expression of fibroblasts was also investigated using direct or indirect coculture systems. For the fibroblasts that originally did not produce HGF, cancer cells failed to show any HGF-inductive effect. For the HGF-producing fibroblasts, despite of somewhat upregulation or downregulation in fibroblast HGF expression, the feedback regulation by studied pancreatic cancer cells in both coculture modes were relatively limited. This in vitro study sketched out the interaction between cancerous and stromal compartments with an emphasis on HGF/c-Met signal pathway, thus possibly helping to unveil the more complicated mutual modulation in vivo between pancreatic cancer and host mesenchymal tissues. 相似文献
59.
Ochiai N Shimazaki C Uchida R Fuchida S Okano A Ashihara E Inaba T Fujita N Nakagawa M 《Leukemia & lymphoma》2003,44(2):369-372
A 62-year-old man diagnosed with acute myelogenous leukemia which had developed from myelodysplastic syndrome received cytarabine and idarubicine as an induction therapy. The patient developed pneumonia and bacterial sepsis during profound neutropenia. Fever and sepsis improved by using many anti-bacterials and anti-fungals but he became febrile again and complained of severe lumbar pain. 67Ga scintigram showed abnormal uptake in the lumbar vertebra and left sternoclavicular joint, suggesting a diagnosis of discitis and osteomyelitis in the lumbar vertebra and sternoclavicular arthritis. We biopsied the site several times but culture of the biopsy specimen could not isolate any pathogens, and high fever persisted for about 10 months despite administration of various anti-bacterials and anti-fungals. Finally we inserted a catheter into the abscess at the iliopsoas muscle and Scedosporium apiospermum was isolated in the bloody pus obtained from the catheter. Itraconazole and amphotericin B were restarted, and the high fever and lumbar pain improved rapidly. The findings of S. apiospermum infection in this patient emphasizes the importance of being aware of this pathogen in patients with hematologic malignancy during the neutropenic phase. 相似文献
60.
Attenuation of microcirculatory disturbance after liver ischemia by newly synthesized inflammatory cytokine suppressor,FR167653 总被引:1,自引:0,他引:1
Takiguchi M Totsuka E Umehara M Ono H Nara M Nozaki T Wajima N Takahashi K Narumi S Hakamada K Sugai M Sasaki M 《Hepato-gastroenterology》2003,50(51):789-793
BACKGROUND/AIMS: Inflammatory cytokines, such as interleukin-1 beta and tumor necrosis factor-alpha, which activate neutrophils, contribute to hepatic warm ischemia-reperfusion injury. However, the role of the cytokines in hepatic microcirculation immediately after reperfusion is still unclear. This study was carried out to investigate whether FR167653, a dual inhibitor of interleukin-1 beta and tumor necrosis factor-alpha, attenuates hepatic microcirculatory disturbance at the initial phase of reperfusion following liver ischemia. METHODOLOGY: Adult mongrel dogs were subjected to 90 minutes of liver ischemia by a Pringle's maneuver under portosystemic bypass. The animals were divided into two groups: a control group (n = 10), subjected to hepatic warm ischemia only, and a FR167653 administered group (n = 5), which received 1 mg/kg/h FR167653 for 4 hours since 30 minutes before the ischemia to 2 hours after the reperfusion continuously. Seven days animal survival, hepatic tissue blood flow, liver function test, hepatic venous blood concentration of endothelin-1 and plasminogen activator inhibitor-1, liver tissue biochemistry, and histopathology were analyzed. RESULTS: The treatment with FR167653 attenuated microcirculatory disturbance, lessened liver injury, enhanced adenine nucleotides resynthesis, and improved animal survival after liver ischemia. In addition, FR167653 significantly inhibited release of both endothelin-1 and plasminogen activator inhibitor-1 from the liver cells. CONCLUSIONS: These results suggest that the inflammatory cytokines induce microcirculatory disturbance in the initial phase of reperfusion following liver ischemia. 相似文献