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BackgroundAmong animal models of schistosomiasis, the rhesus macaque is unique in that an infection establishes but egg excretion rapidly diminishes, potentially due to loss of adult worms from the portal system via shunts or death by immune attack.Principal FindingsTo investigate this, six rhesus macaques were exposed to Schistosoma mansoni cercariae and the infection monitored until portal perfusion at 18 weeks. Despite a wide variation in worm numbers recovered, fecal egg output and circulating antigen levels indicated that a substantial population had established in all animals. Half the macaques had portal hypertension but only one had portacaval shunts, ruling out translocation to the lungs as the reason for loss of adult burden. Many worms had a shrunken and pallid appearance, with degenerative changes in intestines and reproductive organs. Tegument, gut epithelia and muscles appeared cytologically intact but the parenchyma was virtually devoid of content. An early and intense IgG production correlated with low worm burden at perfusion, and blood-feeding worms cultured in the presence of serum from these animals had stunted growth. Using immunoproteomics, gut digestive enzymes, tegument surface hydrolases and antioxidant enzymes were identified as targets of IgG in the high responder animals.SignificanceIt appears that worms starve to death after cessation of blood feeding, as a result of antibody-mediated processes. We suggest that proteins in the three categories above, formulated to trigger the appropriate mechanisms operating in rhesus macaques, would have both prophylactic and therapeutic potential as a human vaccine.

A major challenge in eukaryotic cell biology is to understand the roles of individual proteins and the subcellular compartments in which they reside. Here, we use the localization of organelle proteins by isotope tagging technique to complete the first proteomic analysis of the major organelles of the DT40 lymphocyte cell line. This cell line is emerging as an important research tool because of the ease with which gene knockouts can be generated. We identify 1090 proteins through the analysis of preparations enriched for integral membrane or soluble and peripherally associated proteins and localize 223 proteins to the endoplasmic reticulum, Golgi, lysosome, mitochondrion, or plasma membrane by matching their density gradient distributions to those of known organelle residents. A striking finding is that within the secretory and The chicken pre-B cell line DT40 exhibits a remarkably high ratio of targeted to random integration for transfected DNA constructs. This property is unusual in vertebrate cell lines and enables targeted gene disruption experiments to be carried out with relative ease (1). Consequently, DT40 has become a major research tool for the molecular dissection of a wide range of cellular and biochemical mechanisms in a vertebrate context, including membrane traffic, signal transduction, and cell cycle (2).Proteins in eukaryotic cells are organized according to their functions within a dynamic network of membranes. Localization is therefore paramount in assigning functions to uncharacterized proteins and understanding the processes occurring in subcellular compartments. An increased knowledge of the protein localization within the DT40 cell line would be of great value. Traditional localization methods such as immunofluorescence microscopy are typically low throughput and are more suitably applied to the study of specific proteins of interest rather than the cataloguing of large numbers of proteins. Recent developments in proteomics have made it possible to analyze the protein composition of organelles using a variety of different approaches. Several groups have utilized label-free quantitative proteomics in the high throughput assignment of proteins to subcellular compartments. In one approach, protein correlation profiling, proteins from enriched organelle fractions are quantified by peptide ion intensity measurements (3, 4). Other similar methods employ quantitation by spectral counting, recording the number of ions detected per protein (5, 6). Localization of organelle proteins by isotope tagging (LOPIT) 1 is a complementary approach, which employs isotope labeling for quantitation (7-9). Rather than processing each sample separately as in label-free techniques, differentially labeled fractions are pooled early in the LOPIT protocol. This has the important advantage of reducing the points at which variation might be introduced into the data.LOPIT begins with the partial separation of organelles by density gradient centrifugation and relies on the assumption that proteins from each organelle c...

Objective: Four sets of eight audible alarms matching the functions specified in IEC 60601-1-8 (2012) were designed using known principles from auditory cognition, with the intention that they would be more recognizable and localizable than those currently specified in the standard. Background:The audible alarms associated with IEC 60601-1-(2012), a global medical device standard, are known to be difficult to learn and retain, and there have been many calls to update them. There are known principles of design and cognition which might form the basis of more readily recognizable alarms. There is also scope for improvement in the localizability of the existing alarms.Method: Four alternative sets of alarms matched to the functions specified in IEC 60601-1-8 (2012) were tested for recognizability and localizability, and compared with the alarms currently specified in the standard Results: With a single exception, all prototype sets of alarms outperformed the current IEC set on both recognizability and localizability. Within the prototype sets, 'auditory icons' were the most easily recognized, but the other sets, using word rhythms and simple acoustic metaphors, were also more easily recognized than the current alarms. With the exception of one set, all prototype sets were also easier to localize. Conclusion:Known auditory cognition and perception principles were successfully applied to a known audible alarm problem Application: This work constitutes the first (benchmarking) phase of replacing the alarms currently specified in the standard. The design principles used for each set demonstrates the Medical audible alarms 3 relative ease with which different alarm types can be recognized and localized.Keywords: audition; auditory displays; learning; medical device technologies Precis: Four sets of audible alarms matched to the functions specified in IEC 60601-1-8, a global medical device standard, were designed using known principles of successful audible alarm design. When tested for recognizability and localizability, all sets (with one exception for localizability) outperformed the current alarms specified in the standard. This work represents the first phase of updating the alarms specified in that standard

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Peer review of the quality of care of the medical staff in a healthcare delivery system, properly executed and utilized, can bring about changes that improve the quality and safety of patient care, enhance clinical performance, and augment physician education. Although all healthcare facilities are mandated to conduct peer reviews, the process of how it is conducted, reported, and utilized varies widely. In 2007, our institution, a large public teaching acute care facility, developed and implemented an electronic Medical Staff Peer Review System (MS-PRS) that replaced the existing paper-based system and created a centralized database for all peer review activities. Despite limited resources and mounting known challenges, we have developed and implemented a system that includes 100% mortality reviews, an ongoing random review for reappointment and operative procedures, and morbidity peer reviews. Parallel to the 4-year implementation of the system, we observed a steady, significant downward trend in the medical malpractice claim rate, which can be attributable in part to the implementation of MS-PRS. In this paper, we share our experiences in the development, outcomes, challenges encountered, and lessons learned from MS-PRS and provide our recommendations to similar institutions for the development of such a system.

Clathrin and clathrin-dependent events are evolutionary conserved although it is believed that there are differences in the requirement for clathrin in yeast and higher vertebrates. Clathrin is a long-lived protein and thus, with clathrin knockdowns only long-term consequences of clathrin depletion can be studied. Here, we characterize the first vertebrate temperature-sensitive clathrin heavy chain mutant as a tool to investigate responses to rapid clathrin inactivation in higher eukaryotes. Although we created this mutant using a clathrin cryo-electron microscopy model and a yeast temperature-sensitive mutant as a guide, the resulting temperature-sensitive clathrin showed an altered phenotype compared to the corresponding yeast temperature-sensitive clathrin. First, it seemed to form stable triskelions at the non-permissive temperature although endocytosis was impaired under these conditions. Secondly, as a likely consequence of the stable triskelions at the non-permissive temperature, clathrin also localized correctly to its target membranes. Thirdly, we did not observe missorting of the lysosomal enzyme beta-glucuronidase which could indicate that the temperature-sensitive clathrin is still operating at the non-permissive temperature at the Golgi or, that, like in yeast, more than one TGN trafficking pathway exists. Fourthly, in contrast to yeast, actin does not appear to actively compensate in general endocytosis. Thus, there seem to be differences between vertebrates and yeast which can be studied in further detail with this newly created tool.

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