Antisocial personality disorder (ASPD) and psychopathy involve significant interpersonal and behavioural impairments. However, little is known about their underlying neurobiology and in particular, ...abnormalities in white matter (WM) microstructure. A preliminary diffusion tensor magnetic resonance imaging (DT-MRI) study of adult psychopaths employing tractography revealed abnormalities in the right uncinate fasciculus (UF) (Craig et al., 2009), indicating fronto-limbic disconnectivity. However, it is not clear whether WM abnormalities are restricted to this tract or are or more widespread, including other tracts which are involved in connectivity with the frontal lobe.
We performed whole brain voxel-based analyses on WM fractional anisotropy (FA) and mean diffusivity (MD) maps acquired with DT-MRI to compare 15 adults with ASPD and healthy age, handedness and IQ-matched controls. Also, within ASPD subjects we related differences in FA and MD to measures of psychopathy.
Significant WM FA reduction and MD increases were found respectively in ASPD subjects relative to controls. FA was bilaterally reduced in the genu of corpus callosum while in the right frontal lobe FA reduction was found in the UF, inferior fronto-occipital fasciculus (IFOF), anterior corona radiata and anterior limb and genu of the internal capsule. These differences negatively correlated with measures of psychopathy. Also in the right frontal lobe, increased MD was found in the IFOF and UF, and the corpus callosum and anterior corona radiata. There was a significant positive correlation between MD and psychopathy scores.
The present study confirms a previous report of reduced FA in the UF. Additionally, we report for the first time, FA deficits in tracts involved in interhemispheric as well as frontal lobe connectivity in conjunction with MD increases in the frontal lobe. Hence, we provide evidence of significant WM microstructural abnormalities in frontal brain regions in ASPD and psychopathy.
Flavor physics in the quark sector Asner, D.M.; Bauer, D.; Becher, T. ...
Physics Reports,
2010, Letnik:
494, Številka:
3
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
In the past decade, one of the major challenges of particle physics has been to gain an in-depth understanding of the role of quark flavor. In this time frame, measurements and the theoretical ...interpretation of their results have advanced tremendously. A much broader understanding of flavor particles has been achieved; apart from their masses and quantum numbers, there now exist detailed measurements of the characteristics of their interactions allowing stringent tests of Standard Model predictions. Among the most interesting phenomena of flavor physics is the violation of the CP symmetry that has been subtle and difficult to explore. In the past, observations of CP violation were confined to neutral
K
mesons, but since the early 1990s, a large number of CP-violating processes have been studied in detail in neutral
B
mesons. In parallel, measurements of the couplings of the heavy quarks and the dynamics for their decays in large samples of
K
,
D
, and
B
mesons have been greatly improved in accuracy and the results are being used as probes in the search for deviations from the Standard Model.
In the near future, there will be a transition from the current to a new generation of experiments; thus a review of the status of quark flavor physics is timely. This report is the result of the work of physicists attending the 5th CKM workshop, hosted by the University of Rome “La Sapienza”, September 9–13, 2008. It summarizes the results of the current generation of experiments that are about to be completed and it confronts these results with the theoretical understanding of the field which has greatly improved in the past decade.
Gaucher disease is inherited in an autosomal recessive manner and is the most prevalent lysosomal storage disease. Gaucher disease has marked phenotypic variation and molecular heterogeneity, and ...several simple and complex alleles of the acid beta-glucosidase gene have been identified as causal to this disease. Certain combinations of alleles have been shown to correlate well with the severity of the disease, but many Gaucher disease patients exist whose disease is not explained by any of the published mutations. This study was undertaken to identify mutant alleles in such incompletely characterized Gaucher disease, in an attempt to find further correlations between clinical phenotype and the presence of acid beta-glucosidase alleles. RNA was isolated from Gaucher cell lines and converted to cDNA, the cDNA was amplified by PCR and cloned, and several clones for each allele were sequenced. Several new singly mutated and multiply mutated alleles were identified, and sequence-specific oligonucleotide hybridization was used to verify the presence of these mutations in the genome of these patients. All newly identified mutations occurred only rarely in the Gaucher disease population, making it difficult to determine whether inheritance of a particular combination of alleles always correlates with the clinical manifestations seen in the test patients. Three of the newly described alleles were single missense mutations in exon 8, one was a single missense mutation in exon 5, and the fifth was a complex allele, comprising a series of different point mutations scattered throughout exons 5 and 6.