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131.
W Terpstra H Rozemuller DA Breems EJ Rombouts A Prins DJ FitzGerald RJ Kreitman JJ Wielenga RE Ploemacher B L?wenberg A Hagenbeek AC Martens 《Canadian Metallurgical Quarterly》1997,90(9):3735-3742
We studied the cell kill induced by granulocyte-macrophage colony-stimulating factor (GM-CSF ) fused to Diphtheria Toxin (DT-GM-CSF ) in acute myeloid leukemia (AML) samples and in populations of normal primitive hemopoietic progenitor cells. AML samples from three patients were incubated in vitro with 100 ng/mL DT-GM-CSF for 48 hours, and AML cell kill was determined in a proliferation assay, a clonogenic assay colony-forming unit-AML (CFU-AML) and a quantitative long-term bone marrow (BM) culture ie, the leukemic-cobblestone area forming cell assay (L-CAFC). To measure an effect on cells with in vivo leukemia initiating potential DT-GM-CSF exposed AML cells were transplanted into immunodeficient mice. In two out of three samples it was shown that all AML subsets, including those with long-term abilities in vivo (severe combined immunodeficient mice) and in vitro (L-CAFC assay) were reduced in number by DT-GM-CSF. Cell kill induced by DT-GM-CSF could be prevented by coincubation with an excess of GM-CSF, demonstrating that sensitivity to DT-GM-CSF is specifically mediated by the GM-CSF receptor. Therefore, binding and internalization of GM-CSF probably occur in immature AML precursors of these two cases of AML. The third AML sample was not responsive to either GM-CSF or DT-GM-CSF. The number of committed progenitors of normal bone marrow (burst-forming unit-erythroid, colony-forming unit granulocyte- macrophage, and cobble stone area forming cell [CAFC] week 2) and also the number of cells with long-term repopulating ability, assayed as week 6 CAFC, were unchanged after exposure to DT-GM-CSF (100 ng/mL, 48 hours). These studies show that DT-GM-CSF may be used to eliminate myeloid leukemic cells with long-term potential in vitro and in immunodeficient mice, whereas normal hemopoietic stem cells are spared. 相似文献
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AC Barretto M Wajngarten JB Serro-Azul H Pierri A Nussbacher OC Gebara 《Canadian Metallurgical Quarterly》1997,69(6):375-379
The clinical hemostatic effect of tranexamic acid mouthwash after oral surgery was evaluated in 47 patients receiving oral anticoagulant therapy. Surgery was performed after the anticoagulant medication was reduced in 15 patients (control group) and with no change in anticoagulant therapy in 32 patients (test group). The only statistical difference between the two treatment groups at baseline was the level of anticoagulation, which was significantly higher in the test group. There was no significant difference between the two treatment groups in the incidence of bleeding after oral surgery. The results indicated that a combination of local antifibrinolytic therapy and a local hemostatic agent is effective in preventing postoperative bleeding after oral surgery in patients treated with anticoagulants. 相似文献
134.
Rotaviruses and reoviruses are involved in human and animal diseases. It is known that both viruses penetrate the gastrointestinal tract but their interaction with phagocytic cells is unknown. To study this interaction, peritoneal resident phagocytic cells were used and rotavirus and reovirus replication in peritoneal phagocytic cells was observed. However, rotavirus replication in these cells led to the production of defective particles since MA-104 cells inoculated with rotavirus phagocytic cell lysate did not show any evidence of virus replication. On the basis of these results, we suggest that, although reovirus dissemination may be helped by these phagocytic cells, these cells may control rotavirus infection and probably contribute to the prevention of its dissemination. 相似文献
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A Hartmann EM Golet S Gartiser AC Alder T Koller RM Widmer 《Canadian Metallurgical Quarterly》1999,36(2):115-119
BACKGROUND: Auscultation of patients with mitral annular calcification on echocardiography revealed a particular constellation of findings. OBJECTIVE: To test the hypothesis that a particular auscultatory constellation provides a high degree of certainty in diagnosing the combination of mitral annular calcification and aortic sclerosis so often found in the elderly. METHODS: Two groups of patients were studied to evaluate the particular auscultatory constellation under consideration which consisted of: (1) a harsh ejection systolic murmur heard from the 2nd right interspace to the cardiac apex and usually loudest between the 3rd left interspace and the apex; (2) the murmur radiates from the apex towards the left axilla and radiates poorly or not at all from the 2nd right interspace to the neck, and (3) the 2nd heart sound at the cardiac base is normal in intensity, and no ejection clicks are present. Group 1 consisted of patients with mitral annular calcification on echocardiographic examination, and group 2 consisted of patients in whom the particular constellation of auscultatory findings was present and who were then referred for echocardiographic assessment. RESULTS: The particular auscultatory constellation under investigation allowed the diagnosis of the presence of the combination of mitral annular calcification and aortic sclerosis with substantial accuracy. CONCLUSION: The findings in this exploratory study suggest that the pathologic combination of mitral annular calcification and aortic sclerosis can be diagnosed with a reasonably high degree of certainty in elderly patients, if the particular auscultatory configuration is identified. 相似文献
138.
F Tangy M Ossondo JC Vernant D Smadja O Blétry AC Baglin S Ozden 《Canadian Metallurgical Quarterly》1999,179(2):497-502
Human T cell leukemia virus type I (HTLV-I) sequences were sought in labial salivary glands of patients with HTLV-I-associated myelopathy or tropical spastic paraparesis and of seropositive neurologically healthy carriers. HTLV-I proviral DNA was found by polymerase chain reaction amplification in DNA extracted from lip biopsies of every patient. Viral RNA was found by in situ hybridization in the acini epithelium, as well as in lymphocytic infiltrates. This observation suggests that HTLV-I expression in labial salivary glands could participate in the inflammatory lesions observed in these patients. Some seronegative patients with Sj?gren's syndrome or dryness syndrome were also positive for viral transactivator tax DNA (41% in Martinique and 16% in non-HTLV-I-endemic region). Despite histologic signs of lymphocytic infiltration, no viral expression was found in the labial salivary glands of these patients. 相似文献
139.
PURPOSE: Spitting as an ictal automatism has been rarely reported. We aimed to establish its potential lateralizing and localizing significance. METHODS: Review of patients undergoing surgery for intractable epilepsy at two comprehensive epilepsy centers. RESULTS: Five patients were found who had spitting as a stereotyped automatism of their complex partial seizures. All had evidence of right temporal ictal onset and underwent resective surgery. Two had tumors; one, a cavernous angioma; one, hippocampal gliosis, and one, hippocampal sclerosis. We found no instances of ictal spitting in patients with left hemisphere onset. CONCLUSIONS: Spitting as an automatism in complex partial seizures, although uncommon, may be a localizing sign to the nondominant temporal lobe. 相似文献
140.
Several studies, including histochemical ones, have indicated that nitric oxide (NO) of endothelial origin may be related to the pulmonary vasodilation that occurs at birth. Since no histologic studies have been done of the possible parallel perinatal increase in production of neuronal NO synthase (nNOS) by pulmonary nerve plexuses, we investigated the distribution of nNOS in fetal, neonatal, and adult mouse lung. Lungs from mice aged 13 d gestation to 6 d after birth and lungs of adults were studied through histochemistry for nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) activity and immunocytochemistry. Both techniques gave almost similar results in relation to time of appearance, distribution, and frequency of neural structures positive for NADPH-d and NOS. NADPH-d staining was also applied to whole mounts of developing and adult tracheae. Staining was found from gestational days 13 to 15 onward in a small portion of the neuronal population. In all stages studied, NADPH-d/NOS staining was found in neuron cell bodies in the hilar region and bronchiolar wall, as well as in neuronal processes. Labeled terminal nerve fibers with varicosities were more frequent in pulmonary blood vessels than in airways. In tracheae, similar NADPH-d/NOS-positive nerve plexuses were found. The presence of nNOS in fetal and neonatal mouse respiratory tract suggests that neurally derived NO must play a role in developing lung physiology. However, because no perinatal increase in the number or intensity of staining of nNOS-positive nerve structures was seen, no apparent relation between neural NO and vasodilation can be established at birth. 相似文献