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61.
van der Burg SH Ressing ME Kwappenberg KM de Jong A Straathof K de Jong J Geluk A van Meijgaarden KE Franken KL Ottenhoff TH Fleuren GJ Kenter G Melief CJ Offringa R 《International journal of cancer. Journal international du cancer》2001,91(5):612-618
Tumor-specific T-helper (Th) immunity was found to play a pivotal role in the natural and vaccine-induced immune defense against tumors. Since the majority of cervical cancers express human papillomavirus type 16 (HPV16) E7 oncoprotein, it is important to investigate the Th response against this target antigen in detail. By means of PBMC cultures from HLA-typed healthy donors, we identified the central part of HPV16 E7 (E7(41-72)) as the major immunogenic region within this antigen. Furthermore, we mapped 3 distinct Th epitopes within this region (DR15/E7(50-62), DR3/E7(43-77), DQ2/E7(35-50)). In a parallel approach, employing IFN-gamma ELISPOT analysis, we detected Th immunity against HPV16 E7 in subjects with HPV16+ lesions. Several of these responses matched with the 3 Th epitopes defined in our study. A number of other HPV16+ subjects did not display any E7-specific type 1 cytokine-producing T-cell immunity, indicating failure of the immune response. Our combined data argue for more extensive as well as longitudinal analysis of HPV16-specific T-cell immunity using the ELISPOT assay described, as well as for HPV-specific vaccination of individuals with HPV+ lesions. 相似文献
62.
Esterhuizen AD Franken DR Lourens JG Prinsloo E van Rooyen LH 《Human reproduction (Oxford, England)》2000,15(3):657-661
The development of a sequential diagnostic schedule for patients consulting for infertility disturbances would be an ideal method of approach for clinicians in the absence of an aetiological or pathophysiological diagnosis. Since sperm morphology recorded by strict criteria has often been correlated with fertilization failure, the present study aimed to evaluate the relationship between normal morphology as well as in-vitro fertilization (IVF) rates, with chromatin staining among fertile and subfertile men. Two semen smears were prepared from each specimen obtained from 72 men to record normal morphology and chromatin packaging as recorded by chromomycin A(3) (CMA(3)) staining. Following the semen analyses, the 72 men were divided into the two morphological groups, namely <4% and >4% normal forms. Significantly different percentages of CMA(3) staining (mean +/- SE) were recorded between the two morphological groups, namely 65.9% +/- 3.5 and 44.5% +/- 1.7 (P +/- 0.001). A highly negative significant correlation existed between percentage of normal morphology as recorded by strict criteria and CMA(3) staining. A highly significant and positive correlation was recorded for normal morphology and IVF rates (r +/- 0.45, P +/- 0.0001). A significant negative correlation (r +/- -0.51, P +/- 0.0001) existed between CMA(3) values and IVF rates. The discriminating power of nuclear maturity, as recorded by CMA(3) staining, to identify abnormal morphology values and poor IVF rates was calculated with receiver operator characteristic (ROC) analyses. The areas under the ROC curves were 0.86 for sperm morphology and 0. 74 for IVF rates. The calculated threshold values for CMA(3) staining to distinguish between morphology groups were 48 and 50% for IVF. Chromatin packaging assessment is a valuable addition to the sequential diagnostic programme in an assisted reproductive arena. 相似文献
63.
The impact of late muscular injury after radiotherapy on the well being of patients, particularly those treated at a relatively young age, is often underestimated. To extend the present knowledge, a detailed comparative study of the radiation response of skeletal muscles was performed. The hind limb of rats was irradiated at the age of 30-60 days (young), at approximately 200 days (adult) or at the age of >360 days (old), with single doses ranging from 15-60 Gy. Muscular wet weight, volume and tibia length was followed up to 12 months post-treatment. Radiation treatment resulted in muscular wasting, which was more severe at higher doses. The radiation response depended strongly on the age of the animal at the time of treatment. Radiation induced muscle wasting and stunted tibia growth were more prominent in young animals than in adult or in old rats. ED50 values based on normalized wet weight were 12.5 (11.5-13.6) Gy for young animals and 22.5 (21.8-23.3) Gy for adult animals. The gastrocnemius muscle of young animals appears to be more radiosensitive than the gastrocnemius muscle of adult or old animals. Furthermore, in young animals, severe wasting of the muscles may already occur after relative low radiation doses (single dose of 15 Gy). 相似文献
64.
Neural arch dysplasia of the cervical 4 vertebrae is a rare occurrence. The authors present a case with dysplasia of cervical bodies and posterior arch elements at multiple levels. The embryogenesis of these anomalies is discussed. 相似文献
65.
Functional aspects of human sperm binding to the zona pellucida using the hemizona assay 总被引:1,自引:0,他引:1
C C Coddington D R Franken L J Burkman W T Oosthuizen T Kruger G D Hodgen 《Journal of andrology》1991,12(1):1-8
The hemizona assay (HZA) has facilitated investigations of sperm function in relation to zona pellucida binding. In this study, the authors examined: 1) the association between hyperactivated sperm motility and HZA binding; 2) the binding kinetics and efficiency of sperm from subfertile men; and 3) the influence of sperm freezing and thawing on binding capacity. For each HZA, a nonviable human oocyte was cut into equal zona hemispheres. The mean number of bound sperm and the incidence of hyperactivation were significantly greater for samples of sperm from fertile men compared with sperm from subfertile men (P less than 0.05). Subfertile sperm had a binding curve that paralleled the curve for fertile sperm, although the magnitude of binding was markedly reduced. Freezing and thawing of sperm from fertile samples impaired their capacity to bind to the zona pellucida. The HZA binding efficiency was reduced by 30%, although the binding curves for fresh versus frozen samples remained parallel. 相似文献
66.
67.
A Dobbeleir P R Franken H R Ham C Brihaye M Guillaume F F Knapp J Vandevivere 《Nuclear medicine communications》1991,12(1):27-34
First pass radionuclide angiocardiography (FPRNA) has gained increasing interest because of the development of new 99Tcm-labelled perfusion agents and of new 191Os/191Irm generator systems. The aim of the study was to evaluate the performance capacities of a small field of view single crystal digital gamma camera for 99Tcm and 191Irm at high count rates. The camera dead time for 99Tcm (window 30%) was well corrected up to 300 kcps in fast acquisition mode using the relative decrease of a small shielded reference source. Using the decaying activity method for 191Irm the non-linearity response of the gamma camera was corrected by an 191Os reference soruce up to 210 kcps at 70 keV, 75 kcps at 129 keV and 320 kcps including both peaks. Saturation count rates were respectively 270 kcps, 150 kcps and 420 kcps and high count rate resolution (FWHM) 9.0, 7.3 and 10.3 mm. Since the accuracy of first pass measurements is more sensitive to count rate than to spatial resolution the 50-150 keV window was chosen for clinical studies. In data obtained from 32 ECG gated FPRNA patient studies, the whole field of view count rate during the left ventricular phase ranged from 100 to 250 kcps with 80 to 120 mCi (2960-4400 MBq) of 191Irm and 100 to 180 kcps with 20 to 25 mCi (750-925 MBq) of 99Tcm red blood cells permitting for both tracers accurate non-linearity correction. 相似文献
68.
M.-L. Windt D. R. Franken P. M. De Beer P. J. D. Bouic and T. F. Kruger 《Andrologia》1991,23(3):209-212
Compelling evidence has demonstrated that zona binding represents gamete recognition by sperm binding with high affinity and specificity to complex glycoproteins of the zona pellucida. In the present study we evaluated the hemizona assay (HZA) in the investigation of the interaction of mouse spermatozoa with unfertilized murine oocytes and hemizonae after exposure to solubilized murine zonae pellucidae proteins. The zonae pellucidae were isolated from ovarian tissue following described mincing techniques. The sperm binding characteristics of murine spermatozoa were studied by using SDS-PAGE isolated ZP2 (+/- 120 Kd) and ZP3 (+/- 83 Kd) components of the zona pellucida. Sperm receptor activity was examined in a competitive gamete binding fashion using the HZA as an indicator of sperm/zona interaction. The results illustrated that isolated, solubilized ZP2 and ZP3 glycoprotein moieties of the zona pellucida inhibited sperm binding to hemizonae and oocytes when compared to controls, and that the HZA can be utilized as an internally controlled homologous bioassay to evaluate the effects of zona pellucida proteins on tight binding of spermatozoa to the zona pellucida. 相似文献
69.
W G Franken D B Tuinzing W A van der Kwast 《Nederlands tijdschrift voor geneeskunde》1987,131(31):1329-1330
70.
Discordant uptake (mismatching) of 123I-labeled beta-methyl-piodophenyl-pentadecanoic acid (BMIPP) less than 99mTc-labeled methoxyisobutyl isonitrile (MIBI) is a good predictor of myocardial viability. However, methodological factors can influence assessment of the presence of mismatching because of differences in background activity between the tracers. In this study, we investigated the influence of methodological parameters on the mismatching between BMIPP and MIBI in patients with chronic ischemic heart disease. METHODS: Polar maps were created to quantify the extent of mismatched tissue measured in 10 patients with myocardial infarction according to three methods for data processing: no correction, subtraction of background activity measured in the left ventricle cavity and dual-window scatter correction. Mismatching was expressed as a percentage of the surface of the left ventricle globally as well as for each arterial territory using a BMIPP uptake of at least 10% less than MIBI as the threshold. The results of dobutamine stress echocardiography and the evolution of the regional contractility at 6-mo follow-up were used as references. RESULTS: Mean background activity in the ventricle cavity was 9.3% of the maximum activity for MIBI and 21.4% for BMIPP before, and 2.8% and 8.3% after scatter correction. Fourteen arterial vascular territories demonstrated baseline wall-motion abnormalities; 9 territories showed contractile reserve with dobutamine stress echocardiography. Significant mismatching was found in 5 of 14 regions without correction, 9 of 14 after scatter correction and 13 of 14 after background subtraction. Compared with the evolution of resting regional contractility at follow-up, optimal results were found when using the scatter-corrected data. Without correction, mismatching between BMIPP and MIBI was partially disguised because of the higher noise level in the iodine images. On the contrary, subtraction of background measured by means of a single region of interest overestimated the magnitude of mismatching due to the heterogeneous background distribution in the ventricular cavity. CONCLUSION: In quantifying the presence and extent of mismatching between MIBI and BMIPP in chronic ischemic heart disease, significant differences in the detection of viability are noted according to the acquisition and processing methods used. Scatter correction of the acquisition data is the most accurate and reliable method for identifying viable myocardium. 相似文献