Initial,habitual and compulsive alcohol use is characterized by a shift of cue processing from ventral to dorsal striatum

Aims During the development of drug addiction, initial hedonic effects decrease when substance use becomes habitual and ultimately compulsive. Animal research suggests that these changes are represented by a transition from prefrontal cortical control to subcortical striatal control and within the striatum from ventral to dorsal domains of the striatum, but only limited evidence exists in humans. In this study we address this hypothesis in the context of alcohol dependence. Design, setting and participants Non‐abstinent heavy social drinkers (n = 21, 5.0 ± 1.5 drinks/day, 13 of them were alcohol‐dependent according to DSM‐IV) and light social drinkers (n = 10, 0.4 ± 0.4 drinks/day) were examined. Measurements We used a cue‐reactivity functional magnetic resonance imaging (fMRI) design during which pictures of alcoholic beverages and neutral control stimuli were presented. Findings In the dorsal striatum heavy drinkers showed significant higher activations compared to light drinkers, whereas light social drinkers showed higher cue‐induced fMRI activations in the ventral striatum and in prefrontal areas compared to heavy social drinkers [region of interest analyses, P < 0.05 false discovery rate (FDR)‐corrected]. Correspondingly, ventral striatal activation in heavy drinkers correlated negatively with obsessive‐compulsive craving, and furthermore we found a positive association between cue‐induced activation in the dorsal striatum and obsessive‐compulsive craving in all participants. Conclusions In line with our hypothesis we found higher cue‐induced activation of the ventral striatum in social compared to heavy drinkers, and higher dorsal striatal activation in heavy drinkers. Increased prefrontal activation may indicate that social drinkers activate cortical control when viewing alcohol cues, which may prevent the development of heavy drinking or alcohol dependence. Our results suggest differentiating treatment research depending on whether alcohol use is hedonic or compulsive.     

Interstitial Capillary in Normal and in Transplanted Kidneys: An Ultrastructural Study

Knowledge about the normal structure and pathology of interstitial capillary is limited. Splitting and multilayering of the basal membrane (BM), as a marker of chronic rejection, has been published in association with transplant glomerulopathy. The authors investigated the ultrastructural features of the interstitial capillary basal membrane in normal (15 biopsies) and in transplanted kidneys (27 biopsies from 21 patients), expressing transplant glomerulopathy (8 biopsies from 6 patients), acute tubulo-interstitial rejection (9 biopsies from 6 patients), and recurrent or de novo glomerulonephritis (10 biopsies from 8 patients). All biopsies were fixed in 1%OsO 4, embedded in Epon, and examined by electron microscope. Measurements of the interstitial capillary BM were made. The BM of interstitial capillary of intact kidney was a homogenous continuous structure, 88 nm in width on average. Thickening with diffuse multilayering of BM was most intensive in patients with transplant glomerulopathy, and much less intensive in patients with acute tubulointerstitial rejection and in patients with recurrent or de novo glomerulonephritis. These findings may provide the first information about the morphology of the normal basal lamina of interstitial capillary and support the diagnostic value of interstitial capillary changes in chronic rejection.     

Chromosome microarray analysis should be offered to all invasive prenatal diagnostic testing following a normal rapid aneuploidy test result

Chromosomal microarray analysis (CMA) has now replaced karyotyping in the analysis of prenatal cases with a fetal structural anomaly, whereas in those pregnancies undergoing invasive prenatal diagnosis with a normal fetal ultrasound, conventional karyotyping is still performed. The aims of this study were to establish the diagnostic yield of CMA in prenatal diagnosis, and to provide new data that might contribute to reconsider current practices. We reviewed 2905 prenatal samples with a normal rapid aneuploidy detection test referred for evaluation by CMA testing. Our study revealed pathogenic and reported susceptibility copy number variants associated with syndromic disorders in 4.8% (n = 138/2905) of cases, being 2.8% (n = 81/2905) the estimated added diagnostic value of CMA over karyotyping. Clinically significant CMA abnormality was detected in 5.4% (107/1975) of the fetuses with ultrasound anomalies and in 1.4% (5/345) of those considered as low-risk pregnancies. Our series shows that in prenatal samples, CMA increases 2-fold the diagnostic yield achieved by conventional karyotyping.     

EEG Correlates of Action Observation in Humans

To investigate electrophysiological correlates of action observation electroencephalogram (EEG) was recorded while participants observed repetitive biological (human) or non-biological movements (at a rate of 2 Hz). Steady-state evoked potentials were analyzed and their neural sources were investigated using low resolution electromagnetic tomography analysis (LORETA). Results revealed significantly higher activation in the primary motor and premotor cortex, supplementary motor area as well as the posterior parietal cortices during observation of biological movements, supporting mirror properties of cortical motor neurons. In addition interregional communication was analyzed. Increased coherence for distributed networks at delta (0.5–4 Hz) and lower alpha (8–10 Hz) frequencies were obtained suggesting integration and functional coupling between the activated cortical regions during human action observation.