Late thrombotic occlusion of a malapposed stent 10 months after intracoronary brachytherapy

We report a patient who received a stent following intracoronary 3-irradiation. Despite a good initial angiographic result, the stent appeared to be not fully expanded on intravascular ultrasound imaging at 6-month follow-up. Four months later, sudden thrombotic occlusion occurred shortly after aspirin cessation.     

The phylogenetic affinities of the chaetognaths: a molecular analysis

The chaetognaths, or arrowworms, constitute a small and enigmatic phylum of marine invertebrates whose phylogenetic affinities have long been uncertain. A popular hypothesis is that the chaetognaths are the sister group of the major deuterostome phyla: chordates, hemichordates, and echinoderms. Here we attempt to determine the affinities of the chaetognaths by using molecular sequence data. We describe the isolation and nucleotide sequence determination of 18S ribosomal DNA from one species of chaetognath and one acanthocephalan. Extensive phylogenetic analyses employing a suite of phylogenetic reconstruction methods (maximum parsimony, maximum likelihood, evolutionary parsimony, and two distance methods) suggest that the hypothesized relationship between chaetognaths and the deuterostomes is incorrect. In contrast, we propose that the lineage leading to the chaetognaths arose prior to the advent of the coelomate metazoa.      

Brain imaging in nonhuman primates: insights into drug addiction

In vivo brain imaging enables the systematic examination of trait and state variables that contribute to the etiology of human diseases. This review highlights the use of in vivo imaging in nonhuman primate models of drug abuse. In efforts to translate findings from laboratory animals to humans, monkey models offer considerable advantages over those that use rodents and other species because of their neurobiological similarity to humans and their longer life span, which makes it possible to study individual subjects over several years. This article provides a brief overview of positron emission tomography (PET), magnetic resonance imaging (MRI)-based techniques, and encephalographic approaches, with a focus on methodological issues that investigators new to the field should consider. We discuss PET imaging studies involving the dopamine (DA) system, with a special emphasis on DA D2 receptors, and describe experimental approaches through which PET imaging data can provide information about the neuropharmacological and neurochemical actions of drugs that modify behavior. We also consider the use of imaging to understand the impact and interactions of genetic predispositions and environmental and physiological modulators on disease states. For MRI-based and encephalographic studies, we describe approaches that can provide new information about brain function. Although much work remains to be done to adapt and apply these techniques for routine use in nonhuman primates, there has been much progress. These techniques will provide the foundation for future studies aimed at developing behavioral and pharmacological treatments for many human diseases.     

SCA8 RAN polySer protein preferentially accumulates in white matter regions and is regulated by eIF3F

Spinocerebellar ataxia type 8 (SCA8) is caused by a bidirectionally transcribed CTG·CAG expansion that results in the in vivo accumulation of CUG RNA foci, an ATG‐initiated polyGln and a polyAla protein expressed by repeat‐associated non‐ATG (RAN) translation. Although RAN proteins have been reported in a growing number of diseases, the mechanisms and role of RAN translation in disease are poorly understood. We report a novel toxic SCA8 polySer protein which accumulates in white matter (WM) regions as aggregates that increase with age and disease severity. WM regions with polySer aggregates show demyelination and axonal degeneration in SCA8 human and mouse brains. Additionally, knockdown of the eukaryotic translation initiation factor eIF3F in cells reduces steady‐state levels of SCA8 polySer and other RAN proteins. Taken together, these data show polySer and WM abnormalities contribute to SCA8 and identify eIF3F as a novel modulator of RAN protein accumulation.