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61.
Particulate matter (PM) is becoming an increasing health concern and there is a need to develop detection methods to keep its harmful effects in check. Generation of reactive oxygen species (ROS) by PM is often associated with metal compounds, hence our aim is to screen for a peptide probe towards improved collection and the detection of PM having a high metal content. Peptides are putative recognition molecules due to their versatility and ease of modification to enhance their binding selectivities. PM binding peptides were screened using the peptide array and different binding behaviors in terms of different spot colors (yellow, mixed and gray), indicating the different composition of bound PMs, were observed. The strongest binding peptides were identified as follows: NHVNTNYYPTLH (gray), NGYYPHSHSYHQ (mixed) and HHLHWPHHHSYT (yellow), with relative binding ratios of 125%, 144% and 136%, in comparison with WQDFGAVRSTRS, a peptide screened from a phage display in our previous study. Inductively coupled plasma mass spectrometry (ICPMS) analyses revealed that Co, Ni and Zn content in the PM bound to the HHLHWPHHHSYT peptide spot were respectively 12.5, 15.8 and 7.8 times that of the PM bound to no peptide spot, suggesting this peptide probe is applicable to collect PM with a high metal content.Using peptide array, peptides binding to particulate matter with high metal content were screened and characterized by focusing on the different spot colors (yellow, mixed and gray). 相似文献
62.
Tetsuro Inoue Kazukiyo Oida Yoshio Taguchi Eisaku Tanaka Terufumi Kato Minoru Sakuramoto Masayoshi Minakuchi Yuji Maeda Ko Maniwa Kunihiko Terada Satoshi Noma 《Nihon Kokyūki Gakkai zasshi》2003,41(3):223-227
A 31-year-old man experienced chest pain, fever, bloody sputum and cough after diet therapy. Chest radiography and chest CT showed infiltration in the right lower lung field and right pleural effusion. Pulmonary embolism and infarction was diagnosed using 99mTc-MAA perfusion scans and chest enhanced CT. The patient did not have a thrombotic disposition and deep vein thrombosis in the lower extremities. This case did not have an acute onset or dyspnea, and was not typical of pulmonary embolism. The diet therapy may have caused dehydration and acted as a predisposing cause of pulmonary embolism. 相似文献
63.
Ryohei Miyata Motohide Shimazu Shigeyuki Kawachi Minoru Tanabe Koichi Aiura Go Wakabayashi Masakazu Ueda Masayoshi Sakuma Masaki Kitajima 《Journal of hepato-biliary-pancreatic sciences》2005,12(3):272-276
A 54-year-old woman with giant liver cystadenocarcinoma underwent left trisegmentectomy with combined resection of the inferior vena cava (IVC) and the right hepatic vein. As a result, only the right inferior hepatic vein was preserved as a drainage vein. Because the perivertebral plexus and the azygos vein were both well developed, neither veno-venous bypass nor IVC reconstruction was performed. The developed collateral veins acted as the venous drainage pathway to maintain a stable systemic circulation. On the seventh postoperative day, portal vein flow dramatically decreased and the patient tended to liver failure. Prostaglandin E1 (PGE1) was administrated via the superior mesenteric artery. The portal flow then gradually increased and liver failure was avoided. Six months after the operation, she was re-admitted due to obstructive jaundice and presented with complete stenosis of the common bile duct (CBD). The jaundice persisted and liver dysfunction progressed. The patient died seven months after the operation. The confluence of the right inferior vein and the IVC could have been deformed, causing outflow blockade. The intrinsic shunt was not good enough to act as the drainage pathway, and IVC reconstruction may have been needed. 相似文献
64.
Masayoshi Yokoyama Atsushi Sakamoto Souji Konno Shigeru Sakakibara 《American heart journal》1974,87(1):15-20
Patients with mitral stenosis usually showed a marked increase in the P negativity following exercise. The P terminal force in Lead V1 in 20 cases with isolated mitral stenosis was ?0.090 mm. sec. before exercise, which changed to ?0.177 mm. sec. following the single Master two-step test.Normal adults never showed such changes on exercise. The phenomenon was considered to be due to the posterior rotation of the P wave vector in the horizontal plane, which was induced by the enlargement of the left atrial wall on exercise. 相似文献
65.
Toshitaro Nakagawa Sachiko Matozaki Tohru Murayama Ryuichiro Nishimura Masayoshi Tsutsumi Ryuji Kawaguchi Yasunobu Yokoyama Kazumasa Hikiji Takashi Isobe Kazuo Chihara 《British journal of haematology》1993,85(3):469-476
Summary. A cell line designated SKM-1 was newly established from leukaemic cells of a 76-year-old Japanese male patient with monoblastic leukaemia following myelodysplastic syndrome (MDS). The cells were obtained from peripheral blood of the patient when he lost multiple point mutations of ras genes with acquisition of chromosomal abnormalities during disease progression in MDS. The cells grew as a single floating cell, and have been continuously growing with the morphological characteristics of immature monoblasts by serial passages during the past 42 months with a doubling time of about 48 h. By cytochemical analysis. the cloned cells were positive for butyrate esterase, but negative for the Epstein-Barr virus associated nuclear antigen. Phenotypic analysis revealed the expression of myelomonocyte specific antigens such as CD4, CD13, CD33 and HLA-DR. Cells from the primary peripheral blood and those from SO passages of the SKM-1 cell line both possessed no activated ras genes but showed karyotype abnormalities with 46.XY, del(9)(q13;q22), der(17) t(17:?)(p13:?). The SKM-1 cells have two mutations in p53 gene and overexpress the pS3 products. This cell line may contribute to a better understanding of molecular mechanisms in the progression from MDS to myelogenous leukaemia. 相似文献
66.
Funakoshi Y Shiono H Inoue M Kadota Y Ohta M Matsuda H Okumura M Eimoto T 《Journal of cancer research and clinical oncology》2005,131(5):314-322
Purpose Glucocorticoids exert anti-proliferative effects in various cell types and have long been known to induce apoptosis in thymocytes. Although a few reports have described the regression of human thymoma with glucocorticoid therapy, its effects on neoplastic thymic epithelial cells (TECs) have not been reported. In the present study, we investigated glucocorticoid receptor (GR) expression on neoplastic TECs and the effects of glucocorticoids in vitro on the cell cycle progression of tumor cells.Patients and methods Thymoma specimens were obtained during surgery from 21 patients. Three of the specimens with glucocorticoid therapy were examined using the TdT-mediated dUTP-biotin nick-end labeling method. Primary tumor specimens from ten untreated thymomas were examined for GR expression by immunohistochemistry. Isolated neoplastic TECs from the remaining eight untreated thymomas were examined using immunohistochemistry, flow cytometric and cell cycle analysis.Results GR are expressed on neoplastic TECs as well as on non-neoplastic thymocytes in thymomas, regardless of WHO histological classification. Glucocorticoids caused an accumulation of TEC in G0/G1 phase in all cases examined (n=6), and also induced apoptosis in the three with the lowest levels of Bcl-2 expression.Conclusions Our results indicate that neoplastic TECs express GR and that glucocorticoids directly suppress their in vitro proliferation. 相似文献
67.
Chronic necrotizing pulmonary aspergillosis in pneumoconiosis: clinical and radiologic findings in 10 patients. 总被引:3,自引:0,他引:3
Takashi Kato Ikuji Usami Hiroki Morita Masahiro Goto Masayoshi Hosoda Atsushi Nakamura Shogo Shima 《Chest》2002,121(1):118-127
STUDY OBJECTIVE: To characterize clinical, radiographic, and CT findings of chronic necrotizing pulmonary aspergillosis (CNPA) in patients with pneumoconiosis. METHODS: We studied 10 patients with pneumoconiosis who were seen at Asahi Rosai Hospital and received a clinical diagnosis of CNPA during a 15-year period, and detailed the long-term clinical and radiologic courses of four cases. RESULTS: All patients were men, ranging in age from 48 to 77 years (mean, 60.1 years). Their occupational histories included pottery making (n = 9) and coal mining (n = 1). Chest radiographic findings by the International Labor Organization profusion grading system were greater than category 2. All patients were symptomatic, with a productive cough, hemoptysis, and dyspnea. Serum findings were positive for the Aspergillus antibody in seven patients. The radiologic findings consisted of parenchymal infiltrates and cavities mostly containing mycetoma, which generally involved the upper lobes. The disease progressed slowly; in one patient, broad destruction of the lung was observed after > 10 years without antifungal administration. Most of the patients experienced clinical and radiologic improvement after receiving antifungal therapy, by oral, inhaled, or intracavitary administration. CONCLUSIONS: Chronic persistent or progressive upper-lobe infiltrates and cavities in patients with pneumoconiosis should raise the possibility of CNPA. Early diagnosis and initiation of effective therapy are recommended to achieve a better outcome. 相似文献
68.
Acute myocardial infarction caused by "malignant" anomalous right coronary artery detected by multidetector row computed tomography. 总被引:4,自引:0,他引:4
Minoru Ichikawa Sei Komatsu Hiroshi Asanuma Akio Iwata Tamayo Ishiko Atsushi Hirayama Young-Jae Lim Kazuhisa Kodama Masayoshi Mishima 《Circulation journal》2005,69(12):1564-1567
Anomalous coronary arteries are usually identified incidentally by angiography or autopsy, but some "malignant" coronary anomalies are associated with a high incidence of syncope, arrhythmia, myocardial infarction, and sudden death. So far, the pathogenesis of the coronary events in such cases has only been revealed by autopsy. In the present case report, a patient with anomalous origin of the right coronary artery from the left sinus of Valsalva developed acute myocardial infarction, and visualization of the anomaly and assessment of the culprit plaque in the artery were done by multidetector row computed tomography and intravascular ultrasound. 相似文献
69.
Interaction with human stromal cells enhances CXCR4 expression and engraftment of cord blood Lin(-)CD34(-) cells 总被引:8,自引:0,他引:8
Kobune M Kawano Y Takahashi S Takada K Murase K Iyama S Sato T Takimoto R Niitsu Y Kato J 《Experimental hematology》2008,36(9):1121-1131
OBJECTIVE: Transplantation of hematopoietic stem cells (HSCs) is usually accomplished through intravenous injection, a complex process that requires recognition of bone marrow vasculature and migration to a supportive microenvironment. Hence, some populations of HSCs, including cord blood (CB) Lin(-)CD34(-) stem cells, do not engraft well in bone marrow (BM) of nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice. In this study, we examined the effect of human stromal interactions on the properties of CB Lin(-)CD34(-) cells. MATERIALS AND METHODS: CD34 and CXCR4 expression on fresh CB Lin(-)CD34(-) cells and CB Lin(-)CD34(-) cells cocultured with human stromal cells were analyzed. Homing activity and engraftment of these cells were assessed using NOD/SCID mice. In an attempt to identify the stromal CXCR4-inducing factor, CB Lin(-)CD34(-) cells were cocultured with a noncontact culture system in the presence of several inhibitors. RESULT: Coculture with human stromal cells induced expression of CD34 and CXCR4 on CB Lin(-)CD34(-) cells. CXCR4 expression on CB Lin(-)CD34(-) cells was induced even in the noncontact culture condition, suggesting that this CXCR4-inducing factor is soluble. Moreover, CXCR4 induction was inhibited by the soluble Wnt inhibitor DKK1. Furthermore, these cells acquired homing activity and engrafted in the BM of NOD/SCID mice after intravenous injection. CONCLUSION: These findings may be useful for understanding the role of stromal cells in homing and engraftment of HSCs. 相似文献
70.
Sato T Toki T Kanezaki R Xu G Terui K Kanegane H Miura M Adachi S Migita M Morinaga S Nakano T Endo M Kojima S Kiyoi H Mano H Ito E 《British journal of haematology》2008,141(5):681-688
JAK3 mutations have been reported in transient myeloproliferative disorder (TMD) as well as in acute megakaryoblastic leukaemia of Down syndrome (DS-AMKL). However, functional consequences of the JAK3 mutations in TMD patients remain undetermined. To further understand how JAK3 mutations are involved in the development and/or progression of leukaemia in Down syndrome, additional TMD patients and the DS-AMKL cell line MGS were screened for JAK3 mutations, and we examined whether each JAK3 mutation is an activating mutation. JAK3 mutations were not detected in 10 TMD samples that had not previously been studied. Together with our previous report we detected JAK3 mutations in one in 11 TMD patients. Furthermore, this study showed for the first time that a TMD patient-derived JAK3 mutation (JAK3(I87T)), as well as two novel JAK3 mutations (JAK3(Q501H) and JAK3(R657Q)) identified in an MGS cell line, were activating mutations. Treatment of MGS cells and Ba/F3 cells expressing the JAK3 mutants with JAK3 inhibitors significantly decreased their growth and viability. These results suggest that the JAK3 activating mutation is an early event during leukaemogenesis in Down syndrome, and they provide proof-of-principle evidence that JAK3 inhibitors would have therapeutic effects on TMD and DS-AMKL patients carrying activating JAK3 mutations. 相似文献