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101.
Serum concentrations of DKK-1 correlate with the extent of bone disease in patients with multiple myeloma 总被引:1,自引:0,他引:1
Kaiser M Mieth M Liebisch P Oberländer R Rademacher J Jakob C Kleeberg L Fleissner C Braendle E Peters M Stover D Sezer O Heider U 《European journal of haematology》2008,80(6):490-494
Objectives: Lytic bone disease is a hallmark of multiple myeloma (MM) and is caused by osteoclast activation and osteoblast inhibition. Secretion of Dickkopf (DKK)‐1 by myeloma cells is a major factor which causes inhibition of osteoblast precursors. So far, there is no study showing a significant difference in serum DKK‐1 levels in MM patients with or without lytic bone lesions. Methods: DKK‐1 serum levels were quantified in 184 untreated MM patients and 33 monoclonal gammopathy of undetermined significance (MGUS) patients by ELISA, using a monoclonal anti‐DKK‐1 antibody. Results: Serum DKK‐1 was elevated in MM as compared with MGUS (mean 11 963 pg/mL vs. 1993 pg/mL; P < 0.05). Serum DKK‐1 levels significantly correlated with myeloma stage according to Durie and Salmon (mean 2223 pg/mL vs. 15 209 pg/mL in stage I and II/III, respectively; P = 0.005). Importantly, myeloma patients without lytic lesions in conventional radiography had significantly lower DKK‐1 levels than patients with lytic bone disease (mean 3114 pg/mL vs. 17 915 pg/mL; P = 0.003). Of interest, serum DKK‐1 correlated with the number of bone lesions (0 vs. 1–3 vs. >3 lesions: 3114 pg/mL vs. 3559 pg/mL vs. 24 068 pg/mL; P = 0.002). Conclusion: Using a large series of myeloma patients, we could show for the first time a correlation between DKK‐1 serum concentration and the amount of lytic bone disease, indicating that DKK‐1 is an important factor for the extent of bone disease and supporting the hypothesis of DKK‐1 as a therapeutic target in myeloma bone disease. 相似文献
102.
J Buffington ; CN Shapiro ; RC Holman ; TW Strine ; BJ Grossman ; AE Williams ; MJ Alter ; LB Schonberger 《Transfusion》1994,34(5):371-375
BACKGROUND: In December 1991, the United States Food and Drug Administration received reports of blood donations with unconfirmed reactivity on screening tests for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus (HCV). Of 91 donors with these test results, 57 (63%) reported a recent influenza vaccination. STUDY DESIGN AND METHODS: To determine the extent of unconfirmed reactivity, the time at which it began, and its association or nonassociation with specific manufacturers' tests, a nationwide survey of blood centers was conducted. A case-donation was defined as a blood donation that was repeatedly reactive, but not confirmed positive, on at least two of the three tests from May 1990 through December 1991. RESULTS: Among 14 million donations screened by 110 centers, 582 case-donations were identified. An increase in case- donations was evident in the fall of 1990 (2.8/100,000 donations). In 1991, rates increased from 0.9 per 100,000 donations in the first quarter to 1.3, 3.2, and 19.7 in subsequent quarters. A significantly higher rate of case-donations was observed among donations tested with one of the two available anti-HCV screening tests (8.0 vs. 1.2/100,000 donations; risk ratio = 6.8; 95% CI = 5.4-8.5). CONCLUSION: Although unconfirmed reactivity on multiple screening tests appeared to be seasonal, its documentation prior to the availability of influenza vaccine in 1991 and higher rates among donations tested with one manufacturer's anti-HCV test indicated that test-specific factors were also involved. 相似文献
103.
Rademacher J Morosan P Schormann T Schleicher A Werner C Freund HJ Zilles K 《NeuroImage》2001,13(4):669-683
Despite their potential utility in clinical and research settings, the range of intra- and interindividual variations in size and location of cytoarchitectonically defined human primary auditory cortex (PAC) is largely unknown. This study demonstrates that gyral patterns and the size and location of PAC vary independently to a considerable degree. Thus, the cytoarchitectonic borders of PAC cannot be reliably inferred from macroscopic-MR visible-anatomy. Given the remarkable topographical variability of architectonic areal borders, standard brain mapping which is made solely on the basis of macroanatomic landmarks may lead to structural-functional mismatch. Consequently, interpretations of individual auditory activity patterns might often be inaccurate. In view of the anatomic discrepancies, we generated probability maps of PAC in which the degree of intersubject overlap in each stereotaxic position was quantified. These maps show that the location of PAC in Talairach space differs considerably between hemispheres and individuals. In contrast to earlier cytoarchitectonic work which is based in most cases on studies of single brains, our systematic approach provides extensive microanatomic data as a reference system for studies of human auditory function. 相似文献
104.
The association of platelets with leukocytes was investigated, using gel-filtered platelets stimulated with thrombin and then fixed with formaldehyde. Evidence is presented that stimulation of gel-filtered platelets with low concentrations of thrombin (0.01 to 0.1 U/mL) induces the expression of surface determinants interacting strongly with monocytes and polymorphonuclear leukocytes (PMNs) but only weakly with lymphocytes. Both monocyte-platelet binding and PMN-platelet binding occurred at 37 degrees C and more intensively at 0 degrees C; it was Ca2+-dependent and was unaffected by the addition of sodium azide. The binding also occurred with the monocytoid cell lines HL 60 and U 937 in exponential growth and was much less two days after induction of terminal differentiation by phorbol myristate acetate (PMA). No other tested cell lines (B cells, T cells, and myeloid cells) bound thrombin-stimulated platelets. Monocyte-derived macrophages kept in culture for one week also exhibited reduced binding of thrombin- stimulated platelets. IgG and fibronectin could be ruled out as ligands that mediate binding. 相似文献
105.
A patient, CAL, with gamma heavy chain disease is presented who has had a complete remission lasting over 2 yr with combination chemotherapy consisting of pulsatile cyclophosphamide and prednisone. The patient exhibited many features of an atuoimmune process including a vasculitis, low serum complement levels, a positive antiglobulin (Coombs) test, Raynaud's phenomenon, and keratoconjunctivitis sicca. The CAL paraprotein was found to have several previously undescribed characteristics. It reacted with antisera to Fd, Fab, and Fab', suggesting that most of the Fd portion of the molecule was intace. CAL protein consists of two polypeptide chains of molecular weight 49,000 covalently linked to form a dimer of 95,000 molecular weight. The covalent linkage suggests that the hinge region of this gamma heavy chain is intact. 相似文献
106.
Aminosugar derivatives as potential anti-human immunodeficiency virus agents. 总被引:10,自引:3,他引:10 下载免费PDF全文
A Karpas G W Fleet R A Dwek S Petursson S K Namgoong N G Ramsden G S Jacob T W Rademacher 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(23):9229-9233
Recent data suggest that aminosugar derivatives which inhibit glycoprotein processing have potential anti-human immunodeficiency virus (HIV) activity. These inhibitory effects may be due to disruption of cell fusion and subsequent cell-cell transmission of the acquired immunodeficiency syndrome (AIDS) virus. Free virus particles able to bind CD4-positive cells are still produced in the presence of these compounds with only partial reduction of infectivity. We now report a method to score in parallel both the degree of antiviral activity and the effect on cell division of aminosugar derivatives. We find that (i) the compounds 1,4-dideoxy-1,4-imino-L-arabinitol and N-(5-carboxymethyl-1-pentyl)-1,5-imino-L-fucitol partially inhibit the cytopathic effect (giant cell formation, etc.) of HIV and yield of infectious virus; (ii) the compounds N-methyldeoxynojirimycin and N-ethyldeoxynojirimycin reduce the yield of infectious HIV by an order of four and three logarithms, respectively; and (iii) one compound, N-butyldeoxynojirimycin, of the 47 compounds previously screened reduces infectious viral particles by a logarithmic order greater than five at noncytotoxic concentrations. In addition, long-term growth of infected cells in the presence of N-butyldeoxynojirimycin gradually decreases the proportion of infected cells, leading to eventual elimination of HIV from culture. This result suggests that replication is associated with cytolysis. The ability to break the cycle of replication and reinfection has important implications in the chemotherapy of AIDS. 相似文献
107.
Acute limb ischemia after femoral arterial closure with a vascular sealing device: successful endovascular treatment 总被引:1,自引:0,他引:1
Schiele TM Rademacher A Meissner O Klauss V Hoffmann U 《VASA. Zeitschrift für Gef?sskrankheiten》2004,33(4):252-256
We report on successful catheter therapy of acute occlusions of popliteal and crural arteries due to distal embolization from a vascular sealing device. A 45 years-old male patient underwent percutaneous coronary angiography. After primary successful closure of the right femoral artery by a sealing device the patient developed acute ipsilateral lower limb ischemia, most probably due to embolization of a collagen/thrombin plug. Occlusions of the popliteal and crural vessels were successfully treated by percutaneous thrombectomy, thrombolysis and ballon angioplasty. Combined percutaneous catheter therapy is a therapeutic option for occlusions of popliteal and crural vessels due to embolization from a vascular sealing device. 相似文献
108.
109.
Effects of context‐drug learning on synaptic connectivity in the basolateral nucleus of the amygdala in rats 下载免费PDF全文
David J. Rademacher Nasya Mendoza‐Elias Gloria E. Meredith 《The European journal of neuroscience》2015,41(2):205-215
Context‐drug learning produces structural and functional synaptic changes in the circuitry of the basolateral nucleus of the amygdala (BLA). However, how the synaptic changes translated to the neuronal targets was not established. Thus, in the present study, immunohistochemistry with a cell‐specific marker and the stereological quantification of synapses was used to determine if context‐drug learning increases the number of excitatory and inhibitory/modulatory synapses contacting the gamma‐aminobutyric acid (GABA) interneurons and/or the pyramidal neurons in the BLA circuitry. Amphetamine‐conditioned place preference increased the number of asymmetric (excitatory) synapses contacting the spines and dendrites of pyramidal neurons and the number of multisynaptic boutons contacting pyramidal neurons and GABA interneurons. Context‐drug learning increased asymmetric (excitatory) synapses onto dendrites of GABA interneurons and increased symmetric (inhibitory or modulatory) synapses onto dendrites but not perikarya of these same interneurons. The formation of context–drug associations alters the synaptic connectivity in the BLA circuitry, findings that have important implications for drug‐seeking behavior. 相似文献
110.
AD White M Skelton F Mushtaq TW Pike M Mon-Williams JPA Lodge RM Wilkie 《Annals of the Royal College of Surgeons of England》2015,97(8):608-612