Pathogenesis of dystonia: is it of cerebellar or basal ganglia origin?

Dystonia is a disorder of motor programmes controlling semiautomatic movements or postures, with clinical features such as sensory trick, which suggests sensorimotor mismatch as the basis. Dystonia was originally classified as a basal ganglia disease. It is now regarded as a 'network' disorder including the cerebellum, but the exact pathogenesis being unknown. Rare autopsy studies have found pathology both in the striatum and the cerebellum, and functional disorganisation was reported in the somatosensory cortex in patients. Recent animal studies showed physiologically tight disynaptic connections between the cerebellum and the striatum. We review clinical evidence in light of this new functional interaction between the cerebellum and basal ganglia, and put forward a hypothesis that dystonia is a basal ganglia disorder that can be induced by aberrant afferent inputs from the cerebellum

Chemical Effects on Kβ/Kα X-Ray Intensity Ratio for 97mTc and 95mTc

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Structural insights into initial and intermediate steps of the ribosome-recycling process

The ribosome recycling factor (RRF) and elongation factor G (EF-G) disassemble the 70S post-termination complex (PoTC) into mRNA, tRNA, and two ribosomal subunits. We have determined cryo-EM structures of the PoTC•RRF complex, with and without EF-G. We find that domain II of RRF initially interacts with universally conserved residues of the 23S rRNA helices 43 and 95, and protein L11 within the 50S ribosomal subunit. Upon EF-G binding, both RRF and tRNA are driven toward the tRNA-exit (E) site, with a large rotational movement of domain II of RRF toward the 30S ribosomal subunit. During this intermediate step of the recycling process, domain II of RRF and domain IV of EF-G adapt unusual conformations. Furthermore, binding of EF-G to the PoTC•RRF complex reverts the ribosome from ratcheted to unratcheted state. These results suggest that (i) the ribosomal intersubunit reorganizations upon RRF binding and subsequent EF-G binding could be instrumental in destabilizing the PoTC, and (ii) the modes of action of EF-G during tRNA translocation and ribosome recycling steps are markedly different

A Study of Sum Peak Method in Biological Substances by Using 111In

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The Impact of Suspect Descriptions in University Crime Reports on Racial Bias

Crime reports often include suspect descriptions to alert community members and aid in police investigations. However, vague descriptions of suspects with racial identifiers can potentially do more harm than good. We first conducted an archival study to examine the frequency of reporting suspect race, as well as the relationship between the inclusion of race and the likelihood that the suspect was caught. Then we conducted an experimental study to examine how reporting race may affect overt and subtle racial attitudes. We found no significant relationship between the racial identification of a suspect and the likelihood that the suspect was caught in our archival study. However, our findings from the experimental study demonstrate increased overt and subtle racial bias towards Black people when comparing participants who read a crime report with a Black suspect to those who read one about a suspect with no racial identification. Implications and future directions are discussed