First-trimester diagnosis of late-infantile neuronal ceroid lipofuscinosis (LINCL) by tripeptidyl peptidase I assay and CLN2 mutation analysis

Late-infantile neuronal ceroid lipofuscinosis (LINCL) is a progressive neurodegenerative disorder caused by the deficiency of lysosomal tripeptidyl peptidase I (TPP-I) encoded by the CLN2 gene. We report the first case of early prenatal diagnosis of LINCL by combined enzyme and mutation analysis. TPP-I activity in chorionic villi (CV) was less than 2% of the mean normal control level and g.1946A > G and g.3670C > T mutations were demonstrated, as in the two previously affected children. After termination of pregnancy, TPP-I deficiency was confirmed in cultured CV cells and in the fetal skin fibroblasts. The expression of unequivocal TPP-I deficiency in CV demonstrates that enzyme assay is a reliable option for prenatal diagnosis of LINCL.     

Drug craving and addiction: integrating psychological and neuropsychopharmacological approaches

In the present review, an integrated approach to craving and addiction is discussed, which is based on recent insights from psychology and neuropsychopharmacology. An integrated model explains craving and relapse in humans by the psychological mechanism of "attentional bias" and provides neuropsychopharmacological mechanisms for this bias. According to this model, cognitive processes mediate between drug stimulus and the subject's response to this stimulus and subsequent behavioral response (e.g., drug use, relapse). According to the model, a conditioned drug stimulus produces an increase in dopamine levels in the corticostriatal circuit, in particular the anterior cingulate gyrus, amygdala, and nucleus accumbens, which in turn serves to draw the subject's attention towards a perceived drug stimulus. This process results in motor preparation and a hyperattentive state towards drug-related stimuli that, ultimately, promotes further craving and relapse. Evidence for this attentional bias hypothesis is reviewed from both the psychopharmacological and the neuroanatomical viewpoints. The attentional bias hypothesis raises several suggestions for clinical approaches and further research.     

Natural T-helper immunity against human papillomavirus type 16 (HPV16) E7-derived peptide epitopes in patients with HPV16-positive cervical lesions: identification of 3 human leukocyte antigen class II-restricted epitopes

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.     

Sperm chromatin packaging as an indicator of in-vitro fertilization rates

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.     

Muscle wasting after radiotherapy in young and adult rats

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).     

Congenital dysplasia of C2–6

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.     

Functional aspects of human sperm binding to the zona pellucida using the hemizona assay

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.     

Performance of a single crystal digital gamma camera for first pass cardiac studies

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.     

The hemizona assay (HZA) as an experimental model to evaluate the inhibition of sperm binding to the murine zona pellucida by isolated zona pellucida protein

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.