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31.
Recently it was demonstrated by Gautam, et al. that release of neutrophil-borne heparin-binding protein (HBP), also known as CAP37/azurocidin, induced endothelial hyperpermeability and neutrophil efflux. Here, we show that chronic leg ulcer fluid, in contrast to wound fluid from acute wounds, contains highly increased levels of HBP. Immunohistochemistry demonstrated the presence of HBP in chronic ulcer tissues. Furthermore, secreted products of Pseudomonas aeruginosa were found to induce release of HBP from human neutrophils. Our data suggest a possible link between bacterial presence and HBP-release in chronic ulcers. Thus, targeting HBP offers an interesting option for reduction of endothelial barrier dysfunction in chronic ulcers. 相似文献
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Approaches to improve cellular retention of radiohalogen labels delivered by internalising tumour-targeting proteins and peptides 总被引:1,自引:0,他引:1
Specific targeting of radionuclides is a promising approach to improve diagnosis and treatment of tumors. Targeting vectors may be monoclonal antibodies directed toward tumour-specific antigens or regulatory peptides binding to receptors overexpressed on or by malignant cells. Depending on the aim of the procedure and the biokinetics of the targeting vectors, radionuclides with different nuclear properties (decay scheme, half-life, etc.) must be applied. Halogen radioisotopes are attractive since they exhibit a variety of nuclear properties suitable for various applications. At the same time, their chemistry shows great similarities, which enables the use of similar labelling procedures for different nuclides. A problem in using radiohalogens for labelling of tumour-targeting proteins and peptides is that the commonly used radiohalogenation methods provide labels, which, after internalisation and lysosomal digestion, rapidly "leak" from malignant cells as radiohalogenated degradation products. The main reason for such leakage is free diffusion of the radiometabolites through lysosomal and cellular membranes. This review describes current approaches in molecular design to improve cellular retention of radiohalogen labels. These approaches include the use of prosthetic groups for the attachment of radiohalogens to targeting vectors of bulky hydrophilic non-charged molecules, molecules positively charged at lysosomal pH and negatively charged molecules. The emphasis in this paper is on labelling chemistry and the results of the biological testing of labelled compounds. 相似文献
34.
Lindholm L Bengtsson A Hansdottir V Lundqvist M Rosengren L Jeppsson A 《Journal of cardiothoracic and vascular anesthesia》2003,17(2):182-187
OBJECTIVE: To evaluate the role of target temperature (28 degrees or 34 degrees C) in cardiac surgery on regional oxygenation during hypothermia and rewarming and systemic inflammatory response. DESIGN: Prospective, controlled, and randomized clinical study. SETTING: University hospital. PARTICIPANTS: Elderly patients (mean age 70 +/- 2 years) with acquired heart disease with an anticipated bypass time exceeding 120 minutes (n = 30). INTERVENTIONS: The patients were cooled to either 28 degrees C (n = 15) or 34 degrees C (n = 15). At hypothermia, bypass blood flow was reduced twice from full flow (2.4 L/min/m(2) body surface area [BSA]) to 2.0 L/min/m(2). MEASUREMENTS AND MAIN RESULTS: Hepatic and jugular venous oxygen tension and saturation were higher at 28 degrees C than at 34 degrees C. In comparison with the preoperative values, at 28 degrees C hepatic venous values were higher; whereas at 34 degrees C, they were lower. The reduction of pump blood flow during hypothermia, from 2.4 to 2.0 L/min/m(2)was accompanied by reductions of central, jugular, and hepatic oxygenation at both target temperatures. During rewarming, central and regional venous oxygenation decreased irrespective of the preceding temperature. The decrease was most pronounced in hepatic venous blood, with the lowest individual values <10%. Serum concentrations of C3a and IL-6 increased during hypothermia and increased further during rewarming irrespective of the preceding temperature. CONCLUSION: During cardiopulmonary bypass, hypothermia at 28 degrees C increases regional and central venous oxygenation better than at 34 degrees C. In contrast, venous oxygenation decreases during rewarming irrespective of the preceding temperature. No significant difference in the systemic inflammatory response associated with target temperature was detected. 相似文献
35.
Pagani M Salmaso D Ramström C Jonsson C Lundqvist R Thurfjell L Schnell PO Wägner A Jacobsson H Larsson SA 《Dementia and geriatric cognitive disorders》2001,12(3):177-184
Seventeen patients with probable Alzheimer's disease (AD), 7 patients with frontal lobe dementia (FLD) and 19 control subjects (NOR) were examined by (99m)Tc-d,l- hexamethylpropylene amine oxime ((99m)Tc-HMPAO) SPECT. Images were standardised in the same 3D space and averaged within each group. After normalisation, the three sets of images were analysed in all cerebral lobes, hippocampus, thalamus and basal ganglia. In AD, the (99m)Tc-HMPAO uptake values were significantly reduced, as compared to NOR, in the parietal, temporal and insular lobes. In patients with FLD, the uptake was altered in all lobes with the exception of the parietal lobe. The uptake in the nucleus caudatus decreased significantly in both AD and FLD as compared to NOR. The uptake in the anterior cingulate cortex was significantly reduced in FLD. Subtraction images highlighted all significantly decreased areas. In conclusion, standardising SPECT in a common space and subtracting data from a control group improves the visual interpretation of images. In this study, the typical temporo-parietal and fronto-parietal (99m)Tc-HMPAO uptake reductions were found in AD and FLD, respectively. The uptake in the nucleus caudatus was found to decrease significantly in AD and FLD and the one in the anterior cingulate cortex was reduced in FLD. 相似文献
36.
B Eriksson K Oberg T Andersson G Lundqvist L Wide E Wilander 《Scandinavian journal of gastroenterology》1988,23(4):508-512
Ten patients with malignant endocrine pancreatic tumors were treated with SMS 201-995 at doses of 50 micrograms twice daily, administered subcutaneously. Four out of 10 patients (40%)-1 patient with the Zollinger-Ellison syndrome and 3 of 6 with the watery diarrhea syndrome--responded objectively with more than 50% reduction of peptide levels, with a median duration of 15.5 months. All four patients improved symptomatically, with decreasing dyspeptic symptoms and decreasing diarrhoea. Three additional patients had a clear relief of symptoms without an effect on tumor-secreted peptides. The disease progressed in three patients during treatment. No reduction of tumor mass was seen in any of the patients. The main side effect noted was a slight but maintained increase in fasting blood glucose in four patients. In conclusion, SMS 201-995 had a beneficial effect in more than half of the patients and seems to be a valuable adjunct to other causal therapy in this patient category, especially in acute situations and weak patients because of its very few side effects. 相似文献
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M. Bergström C. Muhr K. Ericson H. Lundqvist A. Lilja L. Eriksson G. Blomquist B. Långström P. Johnström 《Neuroradiology》1987,29(3):221-225
Summary Four patients with radiologically normal pituitary gland were examined with positron emission tomography after the administration of (methyl-11C)-L-methionine. On a following day the examination was repeated with (methyl-11c)-D-methionine. The accumulation rate of L-methionine in the pituitary was measured, giving a value that was about twice that of normal brain tissue. The accumulation rate of D-methionine in the pituitary was almost a factor of 10 lower than that of L-methionine. In the normal brain tissue that ratio was 2.3. The study clearly indicates that the methionine uptake in the pituitary is stereospecific. 11C-D-methionine is freely distributed in the tissue without entrapment, whereas 11C-L-methionine is irreversibly bound. It is concluded that PET with 11C-L-methionine can be used to study amino acid utilization in the pituitary. 相似文献
39.
Malignant carcinoid tumors. An analysis of 103 patients with regard to tumor localization, hormone production, and survival. 总被引:6,自引:0,他引:6 下载免费PDF全文
I Norheim K Oberg E Theodorsson-Norheim P G Lindgren G Lundqvist A Magnusson L Wide E Wilander 《Annals of surgery》1987,206(2):115-125
In a prospective study of 103 patients with carcinoid tumors consecutively referred for medical treatment, the most common sites of the primary tumors were the ileum (73%), bronchi (7%), and jejunum (4%). All patients had local metastases, and 96 (93%) also had liver metastases. The most common initial symptoms were diarrhea (32%), ileus (25%), and flush (23%). The overall frequency of diarrhea was 84% and of flush was 75%. Heart insufficiency caused by cardiac valve disease was seen in 33% of the patients. The carcinoid syndrome, including flush, diarrhea, and elevated urinary 5-hydroxyindole acetic acid (5-HIAA) concentrations, was manifested by 69 patients (67%), 64 of whom (93%) had carcinoid tumors of mid-gut origin. Elevated urinary 5-HIAA was found in 91 patients (88%), of which 89 displayed liver metastases. The plasma concentration of the tachykinin neuropeptide K (NPK) was elevated in 67 patients (66%), 63 of whom had tumors of the mid-gut region. Serum pancreatic polypeptide (PP) and human chorionic gonadotrophin alpha levels were elevated in 43% and 28% of the patients, respectively, and the highest levels were found in patients with metastatic bronchial carcinoid tumors. Thirty-nine of the 103 patients are now dead; 18 died of tumor progression, whereas 14 patients died of heart failure secondary to a carcinoid tricuspidal valve insufficiency. The estimated median survival from the time of histologic diagnosis was 14 years, and from the time of carcinoid syndrome was 8 years. 相似文献
40.
C Muhr M Bergstr?m P O Lundberg K Bergstr?m P Hartvig H Lundqvist G Antoni B L?ngstr?m 《Journal of computer assisted tomography》1986,10(2):175-180
Two patients with pituitary tumors were examined with positron emission tomography (PET) after intravenous administration of 11C-N-methylspiperone. In repeat studies the patients were given 1 mg of intravenous haloperidol prior to the administration of the radioligand to block the dopamine receptors. High uptakes of the radiolabeled ligand were seen in one of the tumors. With haloperidol pretreatment the uptake was lower, probably mainly showing the remaining unspecific binding. The most marked uptake and the largest effect of haloperidol pretreatment was seen in a patient with a hormonally active prolactinoma. Dopamine receptor binding in pituitary tumors can be demonstrated in vivo with PET, and quantification of this binding is possible using a compartmental model. This technique may be useful in improving our understanding of the variable response to medical treatment of prolactinomas with dopamine agonists as well as in the prediction of the effect of such treatment. 相似文献