Revealing nascent proteomics in signaling pathways and cell differentiation.

Regulation of gene expression at the level of protein synthesis is a crucial element in driving how the genetic landscape is expressed. However, we are still limited in technologies that can quantitatively capture the immediate proteomic changes that allow cells to respond to specific stimuli. Here, we present a method to capture and identify nascent proteomes in situ across different cell types without disturbing normal growth conditions, using O-propargyl-puromycin (OPP). Cell-permeable OPP rapidly labels nascent elongating polypeptides, which are subsequently conjugated to biotin-azide, using click chemistry, and captured with streptavidin beads, followed by digestion and analysis, using liquid chromatography-tandem mass spectrometry. Our technique of OPP-mediated identification (OPP-ID) allows detection of widespread proteomic changes within a short 2-hour pulse of OPP. We illustrate our technique by recapitulating alterations of proteomic networks induced by a potent mammalian target of rapamycin inhibitor, MLN128. In addition, by employing OPP-ID, we identify more than 2,100 proteins and uncover distinct protein networks underlying early erythroid progenitor and differentiation states not amenable to alternative approaches such as amino acid analog labeling. We present OPP-ID as a method to quantitatively identify nascent proteomes across an array of biological contexts while preserving the subtleties directing signaling in the native cellular environment

A single H/ACA small nucleolar RNA mediates tumor suppression downstream of oncogenic RAS.

Small nucleolar RNAs (snoRNAs) are a diverse group of non-coding RNAs that direct chemical modifications at specific residues on other RNA molecules, primarily on ribosomal RNA (rRNA). SnoRNAs are altered in several cancers; however, their role in cell homeostasis as well as in cellular transformation remains poorly explored. Here, we show that specific subsets of snoRNAs are differentially regulated during the earliest cellular response to oncogenic RASG12V expression. We describe a novel function for one H/ACA snoRNA, SNORA24, which guides two pseudouridine modifications within the small ribosomal subunit, in RAS-induced senescence in vivo. We find that in mouse models, loss of Snora24 cooperates with RASG12V to promote the development of liver cancer that closely resembles human steatohepatitic hepatocellular carcinoma (HCC). From a clinical perspective, we further show that human HCCs with low SNORA24 expression display increased lipid content and are associated with poor patient survival. We next asked whether ribosomes lacking SNORA24-guided pseudouridine modifications on 18S rRNA have alterations in their biophysical properties. Single-molecule Fluorescence Resonance Energy Transfer (FRET) analyses revealed that these ribosomes exhibit perturbations in aminoacyl-transfer RNA (aa-tRNA) selection and altered pre-translocation ribosome complex dynamics. Furthermore, we find that HCC cells lacking SNORA24-guided pseudouridine modifications have increased translational miscoding and stop codon readthrough frequencies. These findings highlight a role for specific snoRNAs in safeguarding against oncogenic insult and demonstrate a functional link between H/ACA snoRNAs regulated by RAS and the biophysical properties of ribosomes in cancer

Human Population Density and Extinction Risk in the World's Carnivores

Understanding why some species are at high risk of extinction, while others remain relatively safe, is central to the development of a predictive conservation science. Recent studies have shown that a species' extinction risk may be determined by two types of factors: intrinsic biological traits and exposure to external anthropogenic threats. However, little is known about the relative and interacting effects of intrinsic and external variables on extinction risk. Using phylogenetic comparative methods, we show that extinction risk in the mammal order Carnivora is predicted more strongly by biology than exposure to high-density human populations. However, biology interacts with human population density to determine extinction risk: biological traits explain 80% of variation in risk for carnivore species with high levels of exposure to human populations, compared to 45% for carnivores generally. The results suggest that biology will become a more critical determinant of risk as human populations expand. We demonstrate how a model predicting extinction risk from biology can be combined with projected human population density to identify species likely to move most rapidly towards extinction by the year 2030. African viverrid species are particularly likely to become threatened, even though most are currently considered relatively safe. We suggest that a preemptive approach to species conservation is needed to identify and protect species that may not be threatened at present but may become so in the near future

Outcomes and satisfaction of two optional cadaveric dissection courses: a 3-year prospective study

Teaching time dedicated to anatomy education has been reduced at many medical schools around the world, including Nova Medical School in Lisbon, Portugal. In order to minimize the effects of this reduction, the authors introduced two optional, semester-long cadaveric dissection courses for the first two years of the medical school curriculum. These courses were named Regional Anatomy I (RAI) and Regional Anatomy II (RAII). In RAI, students focus on dissecting the thorax, abdomen, pelvis, and perineum. In RAII, the focus shifts to the head, neck, back, and upper and lower limbs. This study prospectively analyzes students' academic achievement and perceptions within the context of these two, newly-introduced, cadaveric dissection courses. Students' satisfaction was assessed anonymously through a questionnaire that included items regarding students' perception of the usefulness of the courses for undergraduate teaching, as well as with regards to future professional activity. For each of the three academic years studied, the final score (1 to 20) in General Anatomy (GA), RAI, and RAII was on average 14.26 ± 1.89; 16.94 ± 1.02; 17.49 ± 1.01, respectively. The mean results were lower in GA than RAI or RAII (P < 0.001). Furthermore, students who undertook these courses ranked them highly with regards to consolidating their knowledge of anatomy, preparing for other undergraduate courses, and training for future clinical practice. These survey data, combined with data on participating students' academic achievement, lend strong support to the adoption of similar courses as complementary and compulsory disciplines in a modern medical curriculum

Why health visiting? Examining the potential public health benefits from health visiting practice within a universal service: A narrative review of the literature

INTRODUCTION: There is increasing international interest in universal, health promoting services for pregnancy and the first three years of life and the concept of proportionate universalism. Drawing on a narrative review of literature, this paper explores mechanisms by which such services might contribute to health improvement and reducing health inequalities. OBJECTIVES: Through a narrative review of empirical literature, to identify: DESIGN: The paper draws upon a scoping study and narrative review. REVIEW METHODS: We used three complementary approaches to search the widely dispersed literature: Our key inclusion criterion was information about health visiting practice. We included empirical papers from United Kingdom (UK) from 2004 to February 2012 and older seminal papers identified in search (3), identifying a total of 348 papers for inclusion. A thematic content analysis compared the older (up to 2003) with more recent research (2004 onwards). RESULTS: The analysis revealed health visiting practice as potentially characterized by a particular 'orientation to practice.' This embodied the values, skills and attitudes needed to deliver universal health visiting services through salutogenesis (health creation), person-centredness (human valuing) and viewing the person in situation (human ecology). Research about health visiting actions focuses on home visiting, needs assessment and parent-health visitor relationships. The detailed description of health visitors' skills, attitudes, values, and their application in practice, provides an explanation of how universal provision can potentially help to promote health and shift the social gradient of health inequalities. CONCLUSIONS: Identification of needs across an undifferentiated, universal caseload, combined with an outreach style that enhances uptake of needed services and appropriate health or parenting information, creates opportunities for parents who may otherwise have remained unaware of, or unwilling to engage with such provision. There is a lack of evaluative research about health visiting practice, service organization or universal health visiting as potential mechanisms for promoting health and reducing health inequalities. This paper offers a potential foundation for such research in future

Health visitor education for today's britain: Messages from a narrative review of the health visitor literature

Highlights •An aspirational ‘orientation to practice’ underpins all health visitors' work •Practice focuses on home visiting, forming relationships and needs assessments •Health visitors' knowledge, skills and abilities are central to effective practice •The large amount of the learning needed is not well covered by current preparation •A radical re-think of health visitor education is needed to accommodate the depth and breadth of knowledge skills and abilities required for practice Objectives This paper draws on a narrative review of the literature, commissioned to support the Health Visitor Implementation Plan (DH, 2011a), and aimed at identifying messages about the knowledge, skills and abilities needed by health visitors to work within the current system of health care provision. Design The scoping study and narrative review used three complementary approaches: a broad search, a structured search and a seminal paper search to identify empirical papers from the health visitor literature for review. The key inclusion criteria were messages of relevance for practice. Data Sources 378 papers were reviewed. These included empirical papers from the United Kingdom (UK) from 2004 – February 2012, older research identified in the seminal paper search and international literature from 2000- January 2016. Review Methods The review papers were read by members of the multi-disciplinary research team which included health visitor academics, social scientists and a clinical psychologist managed the international literature. Thematic content analysis was used to identify main messages. These were tabulated and shared between researchers in order to compare emergent findings and to confirm dominant themes. Results The analysis identified an ‘orientation to practice’ based on salutogenesis (health creation), human valuing (person-centred care) and viewing the person in situation (human ecology) as the aspirational core of health visitors' work. This was realised through home visiting, needs assessment and relationship formation at different levels of service provision. A wide range of knowledge, skills and abilities were required, including knowledge of health as a process and skills in engagement, building trust and making professional judgments. These are currently difficult to impart within a 45 week health visitor programme and are facilitated through ad hoc post registration education and training. The international literature reported both similarities and differences between the working practices of health visitors in the UK and public health nurses worldwide. Challenges related to the education of each were identified. Conclusions The breadth and scope of knowledge, skills and abilities required by health visitors makes a review of current educational provision desirable. Three potential models for health visitor education are described

In the absence of a “landscape of fear”: How lions, hyenas, and cheetahs coexist

Abstract Aggression by top predators can create a “landscape of fear” in which subordinate predators restrict their activity to low‐risk areas or times of day. At large spatial or temporal scales, this can result in the costly loss of access to resources. However, fine‐scale reactive avoidance may minimize the risk of aggressive encounters for subordinate predators while maintaining access to resources, thereby providing a mechanism for coexistence. We investigated fine‐scale spatiotemporal avoidance in a guild of African predators characterized by intense interference competition. Vulnerable to food stealing and direct killing, cheetahs are expected to avoid both larger predators; hyenas are expected to avoid lions. We deployed a grid of 225 camera traps across 1,125 km2 in Serengeti National Park, Tanzania, to evaluate concurrent patterns of habitat use by lions, hyenas, cheetahs, and their primary prey. We used hurdle models to evaluate whether smaller species avoided areas preferred by larger species, and we used time‐to‐event models to evaluate fine‐scale temporal avoidance in the hours immediately surrounding top predator activity. We found no evidence of long‐term displacement of subordinate species, even at fine spatial scales. Instead, hyenas and cheetahs were positively associated with lions except in areas with exceptionally high lion use. Hyenas and lions appeared to actively track each, while cheetahs appear to maintain long‐term access to sites with high lion use by actively avoiding those areas just in the hours immediately following lion activity. Our results suggest that cheetahs are able to use patches of preferred habitat by avoiding lions on a moment‐to‐moment basis. Such fine‐scale temporal avoidance is likely to be less costly than long‐term avoidance of preferred areas: This may help explain why cheetahs are able to coexist with lions despite high rates of lion‐inflicted mortality, and highlights reactive avoidance as a general mechanism for predator coexistence