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The synthesis of the title compounds starting from 2-Chlormethylbenzdioxan and Tetrahydroisochinolines is presented. Their actions on the platelet aggregation and the inhibition of alpha-adrenoceptors at the isolated rabbit aorta and the vas deferens of the guinea pig were investigated.  相似文献   
3.
Targeting proteins that are overexpressed in atherosclerotic plaques may open novel diagnostic applications. The C domain of tenascin-C is absent from normal adult tissues but can be inserted during tumor progression or tissue repair into the molecule by alternative splicing. We tested the ability of the human antibody G11, specific to this antigen, to reveal murine atherosclerotic plaques ex vivo. The antibody directed against the extra domain B of fibronectin (L19) was used as a reference. METHODS: We intravenously injected (125)I-labeled G11 or L19 antibodies into apolipoprotein E-deficient (ApoE(-/-)) mice and harvested the aortae 4 or 24 h later. En face analyses of distal aortae and longitudinal sections of the aortic arch were performed to compare antibody uptake using autoradiography with plaque staining using oil red O. Plaque macrophages were detected by immunohistochemistry (anti-CD68 staining). Biodistribution of injected antibodies was investigated in aortae and blood at 4 and 24 h. RESULTS: En face analyses revealed a significant correlation between radiolabeled G11 and fat-stained areas, increasing from 4 to 24 h, with a correlation coefficient of 0.92 (P < 0.0001) and an average signal-to-noise ratio of 104:1 at 24 h. Plaque imaging using L19 showed similar results (r = 0.86; P < 0.0001; signal-to-noise ratio, 72:1 at 24 h). Uptake of radiolabeled antibodies in histologic sections colocalized with fat staining and activated macrophages in aortic plaques. Biodistribution analyses confirmed specific accumulation in aortic plaques as well as rapid blood pool clearance of the antibodies 24 h after injection. Immunofluorescence analyses revealed increased expression of tenascin and fibronectin isoforms in macrophage-rich plaques. CONCLUSION: The antibody G11, specific to the C domain of tenascin-C, visualizes murine atherosclerotic plaques ex vivo. In conjunction with the increased expression of the C domain of tenascin-C in macrophage-rich plaques, the colocalization of G11 uptake with activated macrophages, and the favorable target-to-blood ratio at 24 h, this antibody may be useful for molecular imaging of advanced atherosclerotic plaques in the intact organism.  相似文献   
4.
Implant surface morphology regulates osteoblast phenotypic expression. Osteoblast sensitivity to non-biologic surfaces suggests that native bone surface features may also affect osteoblast response. To test this, MG63 osteoblast-like cells were grown for 7 days on bovine cortical bone wafers pretreated with rat bone marrow osteoclasts for 0, 10 or 20 days. Response to osteoclast-treated surfaces was compared to the response of MG63 cells to titanium surfaces with smooth and rough microtopographies. Cell number, differentiation (alkaline phosphatase activity and osteocalcin levels), and local factors (PGE(2) and TGF-beta1) were measured in confluent cultures. Compared to culture on plastic, cell number was reduced on all three types of bone wafers; this effect was dose-dependent with increasing resorption of the surface. Alkaline phosphatase specific activity was increased (P相似文献   
5.
The movement of surface mounted targets (SMT) on a shell at the mid-shank and of bone mounted targets attached to the distal shank using a Percutaneous Skeletal Tracker (PST) were simultaneously measured during free-speed walking of three adult subjects having different body types. Surface movement errors in shank kinematic estimates were determined by expressing the segmental motion derived from the SMT relative to the PST-based segment coordinate system (SCS) located at the segment center of gravity. The greatest errors were along and around the shank longitudinal axis, with peak magnitudes of 10 mm of translation and 8° of rotation in one subject. Estimates of knee joint center locations differed by less than 11 mm in each SCS direction. Differences in estimates of net knee joint forces and moments were most prominent during stance phase, with magnitudes up to 39 N in the shank mediolateral direction and 9 N.m about the mediolateral axis. The differences in kinetics were primarily related to the effect of segment position and orientation on the expression of joint forces and on the magnitude and expression of joint moments.  相似文献   
6.
An Enzyme immunoassay for the quantitative determination of vinpocetine (CAS-42971-09-5) in human plasma has been developed. The lower limit of quantification is 0.1 ng/ml plasma. The assay shows no cross reactivity with the major metabolite apovincaminic acid. Because of a strong unspecific binding of vinpocetine to plasma proteins an extraction step was necessary. The inter- and intra-assay reproducibility of the test (coefficient of variation) is in a range of 1.1 and 18.3%.  相似文献   
7.
We present the case of a 40-year-old female patient with sudden onset of anisocoria and unilateral ptosis of the left eye. With the exception of several previous episodes of nausea and vomiting, mild headache and tiredness, combined with the early death of the patient’s mother following aortic rupture, patient history and clinical condition showed no pathological findings. Following indicative findings on duplex sonography, a dissection of the left internal carotid artery from its origin to its distal section was detected on CT angiography of the brain vessels and the diagnosis of Horner syndrome due to internal carotid artery dissection was made. Since this condition is associated with serious embolic complications, prompt treatment following diagnosis is of utmost importance. Our patient was treated conservatively using PTT (partial thromboplastin time)-effective heparinisation. Regular checks including kidney ultrasound, blood pressure measurement, imaging and continuous therapy with acetylsalicylic acid are recommended.  相似文献   
8.
Overall treatment results of chronic hepatitis C have improved markedly with the introduction of pegylated interferon-alpha (PEG–IFN-) and ribavirin combination therapy. However, cure rates in the most common genotype 1 infection are still unsatisfactory. IFN- dose–response studies on viral kinetics suggest that inadequate dosing might be a key factor but drug levels have hardly been tested, which is in part due to difficulties in measuring this cytokine in patient samples. We have shown recently that hepatitis C virus (HCV) replicons are highly sensitive to IFN-. In this report we tested whether the replicon system could be used as a sensitive bioassay to determine the amount of biologically active IFN- in serum or heparinized plasma of patients under therapy. To facilitate the measurements, a stably replicating subgenomic HCV RNA was developed that carries the gene encoding the firefly luciferase. Dose response studies with IFN- demonstrate that the amount of expressed luciferase directly correlates with the level of HCV replication. By using this cell-based assay, serum samples of HCV patients treated with different types and doses of IFN- were analyzed in parallel to IFN- standards made by serial dilutions of the same type of IFN- the patient was treated with. Based on nonlinear logistic models serum concentrations corresponding to 1.3–19 U/ml were determined in patients under standard or high dose IFN- therapy, and from 3.8 to 4.1 ng/ml in patients treated with PEG IFN-. In conclusion, the HCV-replicon based bioassay allows determining the levels of biologically active IFN- in serum and heparinized plasma of patients under treatment.  相似文献   
9.
Grading schemes for meningiomas have traditionally designated tumors as "meningioma," "atypical meningioma," or "anaplastic (malignant) meningioma," depending upon the presence of histopathologic features thought to indicate aggressive behavior. In the past, most systems have considered brain invasion by tumor as the best evidence of malignancy. Perry et al. have recently investigated the significance brain invasion as a prognostic feature in meningiomas. The authors studied a series of 116 patients who had been diagnosed previously with "malignant meningioma" due to the presence of brain invasion, histologic anaplasia, or metastasis. On the basis of a multivariate analysis of histopathologic features and their relationship to tumor recurrence and patient survival, the authors concluded that brain invasion should be considered one of the diagnostic features of atypical meningioma. Accordingly, the diagnosis of malignant meningioma should be reserved for those tumors that are frankly anaplastic and/or contain (> = 20 mitoses per 10 high-power fields (HPF). Due in large part to the strength of evidence in this study, the World Health Organization (WHO) has adopted a grading scheme for meningiomas that incorporates many of the authors' proposals. New diagnostic criteria will result in improved reproducibility with fewer diagnoses of malignant meningioma (WHO grade III).  相似文献   
10.
Retinoblastoma: revisiting the model prototype of inherited cancer   总被引:4,自引:0,他引:4  
Hereditary retinoblastoma is an autosomal dominant disorder caused by mutations in the RB1 gene. Analysis of this rare condition has helped to elucidate the mechanisms underlying hereditary cancer predisposition in general. As identification of RB1 gene mutations has become a part of clinical management of patients with retinoblastoma, there is now a wealth of data. In this article, we summarize the current knowledge on the relations between the genotype and phenotypic expression. Moreover, detailed analysis of genotype-phenotype relations shows that hereditary retinoblastoma has features of a complex trait.  相似文献   
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