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The protein kinase PINK1 and ubiquitin ligase Parkin promote removal of damaged mitochondria via a feed‐forward mechanism involving ubiquitin (Ub) phosphorylation (pUb), Parkin activation, and ubiquitylation of mitochondrial outer membrane proteins to support the recruitment of mitophagy receptors. The ubiquitin ligase substrate receptor FBXO7/PARK15 is mutated in an early‐onset parkinsonian–pyramidal syndrome. Previous studies have proposed a role for FBXO7 in promoting Parkin‐dependent mitophagy. Here, we systematically examine the involvement of FBXO7 in depolarization and mtUPR‐dependent mitophagy in the well‐established HeLa and induced‐neurons cell systems. We find that FBXO7−/− cells have no demonstrable defect in: (i) kinetics of pUb accumulation, (ii) pUb puncta on mitochondria by super‐resolution imaging, (iii) recruitment of Parkin and autophagy machinery to damaged mitochondria, (iv) mitophagic flux, and (v) mitochondrial clearance as quantified by global proteomics. Moreover, global proteomics of neurogenesis in the absence of FBXO7 reveals no obvious alterations in mitochondria or other organelles. These results argue against a general role for FBXO7 in Parkin‐dependent mitophagy and point to the need for additional studies to define how FBXO7 mutations promote parkinsonian–pyramidal syndrome. Synopsis: FBXO7/PARK15 appears to be dispensable for chemically induced PINK1/Parkin‐mediated mitophagy in various cell culture and iNeuron systems. FBXO7/PARK15 is a PD‐risk gene that was previously implicated in PINK1/PARKIN‐dependent mitophagy.Loss of FBXO7 in various cell types (HeLa, HEK293T, hESC‐derived iNeurons) did not lead to significant defects in clearing damaged mitochondria or PINK1/Parkin activation.Purified human FBXO7‐SKP1‐CUL1NTD can directly bind to PSMF1 (PI31) in vitro and with PSMF1/proteasome complexes in cells, suggesting a functional interaction. [ABSTRACT FROM AUTHOR]

Purpose: Timely identification of systematic changes in radiation delivery of an imaging system can lead to a reduction in risk for the patients involved. However, existing quality assurance programs involving the routine testing of equipment performance using phantoms are limited in their ability to effectively carry out this task. To address this issue, the authors propose the implementation of an ongoing monitoring process that utilizes procedural data to identify unexpected large or small radiation exposures for individual patients, as well as to detect persistent changes in the radiation output of imaging platforms. Methods: Data used in this study were obtained from records routinely collected during procedures performed in the cardiac catheterization imaging facility at St. Andrew's War Memorial Hospital, Brisbane, Australia, over the period January 2008-March 2010. A two stage monitoring process employing individual and exponentially weighted moving average (EWMA) control charts was developed and used to identify unexpectedly high or low radiation exposure levels for individual patients, as well as detect persistent changes in the radiation output delivered by the imaging systems. To increase sensitivity of the charts, we account for variation in dose area product (DAP) values due to other measured factors (patient weight, fluoroscopy time, and digital acquisition frame count) using multiple linear regression. Control charts are then constructed using the residual values from this linear regression. The proposed monitoring process was evaluated using simulation to model the performance of the process under known conditions. Results: Retrospective application of this technique to actual clinical data identified a number of cases in which the DAP result could be considered unexpected. Most of these, upon review, were attributed to data entry errors. The charts monitoring the overall system radiation output trends demonstrated changes in equipment performance associated with relocation of the equipment to a new department. When tested under simulated conditions, the EWMA chart was capable of detecting a sustained 15% increase in average radiation output within 60 cases (<1 month of operation), while a 33% increase would be signaled within 20 cases. Conclusions: This technique offers a valuable enhancement to existing quality assurance programs in radiology that rely upon the testing of equipment radiation output at discrete time frames to ensure performance security. [ABSTRACT FROM AUTHOR]

Chemical contaminants may play a role in the etiology of external skin lesions on walleyes Stizostedion vitreum in the Great Lakes. We examined the population of walleyes spawning in the Thames River, Ontario, for skin lesions, and compared contaminant levels in walleyes with conspicuous lesions to contaminant levels in visibly normal walleyes. In 1987, 9% of postspawning downstream migrants exhibited skin lesions. Twenty affected fish, many with multiple abnormalities, were autopsied and the external skin lesions were examined histologically. Eight walleyes were affected by only lymphocystis, seven by only dermal sarcoma, four by both conditions, and one by a calcareous nodule; 68% of the individual lesions affecting these walleyes were lymphocystis. Muscle tissue from the walleyes with lymphocystis or dermal sarcoma had lower concentrations of polychlorinated biphenyls, hexachlorobenzene, and the DDT metabolite p, p-DDE than did muscle from unaffected walleyes. Thus, it appears unlikely that contaminants, such as measured in this study, increase the susceptibility of these walleyes to skin diseases such as lymphocystis and dermal sarcoma. [ABSTRACT FROM AUTHOR]

ABSTRACT Fauna from the Lateglacial Interstadial are largely limited to isolated findspots. Here we report on material from the site of Kent's Bank Cavern, Cumbria, dated to the Allerød/Younger Dryas boundary. The identification of elk ( Alces alces) and horse ( Equus sp.) and the inferred presence of a large canid indicates that fauna of economic utility to humans were in this area at the time. The presence of humans is attested to by records of Federmesser points from two nearby cave sites. We also report on early Mesolithic human remains from Kent's Bank Cavern. This assemblage represents one of very few Lateglacial faunas in northern Britain, and the most northerly early Mesolithic human remains in the British Isles, making Kent's Bank of importance to discussions of both resource distribution and mortuary rituals in these periods. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]