Comparative Morphology of the Penis and Clitoris in Four Species of Moles (Talpidae).

The penile and clitoral anatomy of four species of Talpid moles (broad-footed, star-nosed, hairy-tailed, and Japanese shrew moles) were investigated to define penile and clitoral anatomy and to examine the relationship of the clitoral anatomy with the presence or absence of ovotestes. The ovotestis contains ovarian tissue and glandular tissue resembling fetal testicular tissue and can produce androgens. The ovotestis is present in star-nosed and hairy-tailed moles, but not in broad-footed and Japanese shrew moles. Using histology, three-dimensional reconstruction, and morphometric analysis, sexual dimorphism was examined with regard to a nine feature masculine trait score that included perineal appendage length (prepuce), anogenital distance, and presence/absence of bone. The presence/absence of ovotestes was discordant in all four mole species for sex differentiation features. For many sex differentiation features, discordance with ovotestes was observed in at least one mole species. The degree of concordance with ovotestes was highest for hairy-tailed moles and lowest for broad-footed moles. In relationship to phylogenetic clade, sex differentiation features also did not correlate with the similarity/divergence of the features and presence/absence of ovotestes. Hairy-tailed and Japanese shrew moles reside in separated clades, but they exhibit a high degree of congruence. Broad-footed and hairy-tailed moles reside within the same clade but had one of the lowest correlations in features and presence/absence of ovotestes. Thus, phylogenetic affinity and the presence/absence of ovotestes are poor predictors for most sex differentiation features within mole external genitalia

Bait preferences of Australian dung beetles (Coleoptera: Scarabaeidae) in tropical and subtropical Queensland forests

Dung beetles (Scarabaeinae) are mainly coprophagous. Globally, many species co-exist with large mammalian fauna in grasslands and savannahs. However, tropical and subtropical rainforests, where large herbivorous mammals are scarce, support numerous dung beetle species. Many rainforest dung beetles have been shown to be generalist saprophages or specialists on non-dung food resources. In Australian rainforests, observations of native dung beetles have indicated that some species are attracted to other resources such as fruit or fungi, although the extent to which this occurs is not known. To learn more about the diet breadth of Australian native rainforest dung beetles, we assessed their attraction to a range of baits, including two types of dung, four types of carrion from both vertebrates and invertebrates, three types of rotting fruit and rotting mushrooms. We primarily surveyed rainforest sites but included two dry open-forest sites for comparisons. Of the two groups of Australian native dung beetles (Onthophagini and Australian endemic genera), the latter dominated the rainforest dung beetle fauna and were attracted to a greater variety of baits compared with Onthophagini. The Onthophagini were dominant in open forest and were more likely to be attracted to a particular bait type, primarily dung. Our findings suggest that many of the species belonging to the ‘Australian endemic genera’ are generalist feeders and their ability to utilise a range of food resources contributes to their abundance and diversity in Australian rainforests

Early motion and directed exercise (EMADE) versus usual care post ankle fracture fixation: study protocol for a pragmatic randomised controlled trial

Background: Following surgical fixation of ankle fractures, the traditional management has included immobilisation for 6 weeks in a below-knee cast. However, this can lead to disuse atrophy of the affected leg and joint stiffness. While early rehabilitation from 2 weeks post surgery is viewed as safe, controversy remains regarding its benefits. We will compare the effectiveness of early motion and directed exercise (EMADE) ankle rehabilitation, against usual care, i.e. 6 weeks’ immobilisation in a below-knee cast. Method/design: We have designed a pragmatic randomised controlled trial (p-RCT) to compare the EMADE intervention against usual care. We will recruit 144 independently living adult participants, absent of tissue-healing comorbidities, who have undergone surgical stabilisation of isolated Weber B ankle fractures. The EMADE intervention consists of a non-weight-bearing progressive home exercise programme, complemented with manual therapy and education. Usual care consists of immobilisation in a non-weight-bearing below-knee cast. The intervention period is between week 2 and week 6 post surgery. The primary outcome is the Olerud and Molander Ankle Score (OMAS) patient-reported outcome measure (PROM) at 12 weeks post surgery. Secondary PROMs include the EQ-5D-5 L questionnaire, return to work and return to driving, with objective outcomes including ankle range of motion. Analysis will be on an intention-to-treat basis. An economic evaluation will be included. Discussion: The EMADE intervention is a package of care designed to address the detrimental effects of disuse atrophy and joint stiffness. An advantage of the OMAS is the potential of meta-analysis with other designs. Within the economic evaluation, the cost-utility analysis, may be used by commissioners, while the use of patient-relevant outcomes, such as return to work and driving, will ensure that the study remains pertinent to patients and their families. As it is being conducted in the clinical environment, this p-RCT has high external validity. Accordingly, if significant clinical benefits and cost-effectiveness are demonstrated, EMADE should become a worthwhile treatment option. A larger-scale, multicentre trial may be required to influence national guidelines. Trial registration: ISRCTN, ID: ISRCTN11212729. Registered retrospectively on 20 March 2017

Evolutionary connectionism: algorithmic principles underlying the evolution of biological organisation in evo-devo, evo-eco and evolutionary transitions

The mechanisms of variation, selection and inheritance, on which evolution by natural selection depends, are not fixed over evolutionary time. Current evolutionary biology is increasingly focussed on understanding how the evolution of developmental organisations modifies the distribution of phenotypic variation, the evolution of ecological relationships modifies the selective environment, and the evolution of reproductive relationships modifies the heritability of the evolutionary unit. The major transitions in evolution, in particular, involve radical changes in developmental, ecological and reproductive organisations that instantiate variation, selection and inheritance at a higher level of biological organisation. However, current evolutionary theory is poorly equipped to describe how these organisations change over evolutionary time and especially how that results in adaptive complexes at successive scales of organisation (the key problem is that evolution is self-referential, i.e. the products of evolution change the parameters of the evolutionary process). Here we first reinterpret the central open questions in these domains from a perspective that emphasises the common underlying themes. We then synthesise the findings from a developing body of work that is building a new theoretical approach to these questions by converting well-understood theory and results from models of cognitive learning. Specifically, connectionist models of memory and learning demonstrate how simple incremental mechanisms, adjusting the relationships between individually-simple components, can produce organisations that exhibit complex system-level behaviours and improve the adaptive capabilities of the system. We use the term “evolutionary connectionism” to recognise that, by functionally equivalent processes, natural selection acting on the relationships within and between evolutionary entities can result in organisations that produce complex system-level behaviours in evolutionary systems and modify the adaptive capabilities of natural selection over time. We review the evidence supporting the functional equivalences between the domains of learning and of evolution, and discuss the potential for this to resolve conceptual problems in our understanding of the evolution of developmental, ecological and reproductive organisations and, in particular, the major evolutionary transitions

Diffusion of Protease into Meat & Bone Meal for Solubility Improvement and Potential Inactivation of the BSE Prion

BACKGROUND: Government-imposed feed bans have created a need for new applications for meat & bone meal (MBM). Many potential new applications require MBM protein to be both soluble and free of infectious prion. Treatment with protease is generally effective in reducing insoluble, thermally-denatured proteins to soluble peptides. It has been reported in the literature that certain proteases, including Versazyme™, are able to degrade infectious prions in a system where the prions are readily accessible to proteolytic attack. Prions distributed within MBM, however, may conceivably be protected from proteases. METHODOLOGY/PRINCIPAL FINDINGS: The overall rate of proteolytic MBM digestion depends greatly on whether the protease can penetrate deep within individual particles, or if the protease can only act near the surface of the particle. This research examined the barriers to the diffusion of Versazyme™ into particles of MBM. Confocal microscopy demonstrated differences in the density distributions between the bone and the soft tissue particles of MBM. By tracking the diffusion of fluorescently labeled Versazyme™ through individual particles, it was found that bone particles show full Versazyme™ penetration within 30 minutes, while penetration of soft tissue particles can take up to four hours, depending on the particle's diameter. From the variety of normal proteins comprising MBM, a specific protein was chosen to serve as a prion surrogate based on characteristics including size, solubility, distribution and abundance. This surrogate was used to measure the effect of several factors on Versazyme™ diffusion. CONCLUSIONS/SIGNIFICANCE: Results showed that surrogate distributed in bone particles was more susceptible to degradation than that in soft tissue particles. Three factors controllable by unit operations in an industrial-scale process were also tested. It was found that removing the lipid content and hydrating MBM prior to incubation both significantly increased the rate of surrogate degradation. In a test of particle size, the smallest collected diameter range demonstrated the largest degradation of the prion surrogate, suggesting milling would be beneficial

Patterns of democracy: Coalition governance and majoritarian modification in the United Kingdom, 2010–2015

The UK is often regarded as the archetype of Westminster democracy and as the empirical antithesis of the power-sharing coalitions of Western Europe. Yet, in recent years a different account has emerged that focuses on the subtler institutional dynamics which limit the executive. It is to this body of scholarship that this article responds, locating the recent chapter of coalition government within the wider context of the UK’s democratic evolution. To do so, the article draws Lijphart’s two-dimensional typology of democracies, developing a refined framework that enables systematic comparison over time. The article demonstrates that between over the course of the 2010-15 Parliament, the UK underwent another period of majoritarian modification, driven by factors including the long-term influence of the constitutional forces unleashed under Labour and the short-term impact of coalition management. The article makes several important contributions, salient in the UK and beyond. Theoretically, it offers a critical rejoinder to debates regarding the relationship between institutional design and democratic performance. Methodologically, it demonstrates that the tools of large-scale comparison can be effectively scaled-down to facilitate withincase analysis. Empirically, it provides a series of conclusions regarding the tenability of the UK’s extant democratic architecture under the weight of pressures to which it continues to be subject

Interactions Between Estrogen- and Ah-Receptor Signalling Pathways in Primary Culture of Salmon Hepatocytes Exposed to Nonylphenol and 3,3',4,4'-Tetrachlorobiphenyl (Congener 77)

BACKGROUND: The estrogenic and xenobiotic biotransformation gene expressions are receptor-mediated processes that are ligand structure-dependent interactions with estrogen-receptor (ER) and aryl hydrocarbon receptor (AhR), probably involving all subtypes and other co-factors. The anti-estrogenic activities of AhR agonists have been reported. In teleost fish, exposure to AhR agonists has been associated with reduced Vtg synthesis or impaired gonadal development in both in vivo- and in vitro studies. Inhibitory AhR and ER cross-talk have also been demonstrated in breast cancer cells, rodent uterus and mammary tumors. Previous studies have shown that AhR-agonists potentiate xenoestrogen-induced responses in fish in vivo system. Recently, several studies have shown that AhR-agonists directly activate ERα and induce estrogenic responses in mammalian in vitro systems. In this study, two separate experiments were performed to study the molecular interactions between ER and AhR signalling pathways using different concentration of PCB-77 (an AhR-agonist) and time factor, respectively. Firstly, primary Atlantic salmon hepatocytes were exposed to nonylphenol (NP: 5 μM – an ER agonist) singly or in combination with 0.001, 0.01 and 1 μM PCB-77 and sampled at 48 h post-exposure. Secondly, hepatocytes were exposed to NP (5 μM) or PCB-77 (1 μM) singly or in combination for 12, 24, 48 and 72 h. Samples were analyzed using a validated real-time PCR for genes in the ER pathway or known to be NP-responsive and AhR pathway or known to be PCB-77 responsive. RESULTS: Our data showed a reciprocal inhibitory interaction between NP and PCB-77. PCB-77 produced anti-NP-mediated effect by decreasing the mRNA expression of ER-responsive genes. NP produced anti-AhR mediated effect or as inhibitor of AhRα, AhRR, ARNT, CYP1A1 and UDPGT expression. A novel aspect of the present study is that low (0.001 μM) and medium (0.01 μM) PCB-77 concentrations increased ERα mRNA expression above control and NP exposed levels, and at 12 h post-exposure, PCB-77 exposure alone produced significant elevation of ERα, ERβ and Zr-protein expressions above control levels. CONCLUSION: The findings in the present study demonstrate a complex mode of ER-AhR interactions that were dependent on time of exposure and concentration of individual chemicals (NP and PCB-77). This complex mode of interaction is further supported by the effect of PCB-77 on ERα and ERβ (shown as increase in transcription) with no concurrent activation of Vtg (but Zr-protein) response. These complex interactions between two different classes of ligand-activated receptors provide novel mechanistic insights on signalling pathways. Therefore, the degree of simultaneous interactions between the ER and AhR gene transcripts demonstrated in this study supports the concept of cross-talk between these signalling pathways

Crystal Structure of a Charge Engineered Human Lysozyme Having Enhanced Bactericidal Activity

Human lysozyme is a key component of the innate immune system, and recombinant forms of the enzyme represent promising leads in the search for therapeutic agents able to treat drug-resistant infections. The wild type protein, however, fails to participate effectively in clearance of certain infections due to inherent functional limitations. For example, wild type lysozymes are subject to electrostatic sequestration and inactivation by anionic biopolymers in the infected airway. A charge engineered variant of human lysozyme has recently been shown to possess improved antibacterial activity in the presence of disease associated inhibitory molecules. Here, the 2.04 Å crystal structure of this variant is presented along with an analysis that provides molecular level insights into the origins of the protein's enhanced performance. The charge engineered variant's two mutated amino acids exhibit stabilizing interactions with adjacent native residues, and from a global perspective, the mutations cause no gross structural perturbations or loss of stability. Importantly, the two substitutions dramatically expand the negative electrostatic potential that, in the wild type enzyme, is restricted to a small region near the catalytic residues. The net result is a reduction in the overall strength of the engineered enzyme's electrostatic potential field, and it appears that the specific nature of this remodeled field underlies the variant's reduced susceptibility to inhibition by anionic biopolymers

Histidine Hydrogen-Deuterium Exchange Mass Spectrometry for Probing the Microenvironment of Histidine Residues in Dihydrofolate Reductase

Histidine Hydrogen-Deuterium Exchange Mass Spectrometry (His-HDX-MS) determines the HDX rates at the imidazole C(2)-hydrogen of histidine residues. This method provides not only the HDX rates but also the pK(a) values of histidine imidazole rings. His-HDX-MS was used to probe the microenvironment of histidine residues of E. coli dihydrofolate reductase (DHFR), an enzyme proposed to undergo multiple conformational changes during catalysis.Using His-HDX-MS, the pK(a) values and the half-lives (t(1/2)) of HDX reactions of five histidine residues of apo-DHFR, DHFR in complex with methotrexate (DHFR-MTX), DHFR in complex with MTX and NADPH (DHFR-MTX-NADPH), and DHFR in complex with folate and NADP+ (DHFR-folate-NADP+) were determined. The results showed that the two parameters (pK(a) and t(1/2)) are sensitive to the changes of the microenvironment around the histidine residues. Although four of the five histidine residues are located far from the active site, ligand binding affected their pK(a), t(1/2) or both. This is consistent with previous observations of ligand binding-induced distal conformational changes on DHFR. Most of the observed pK(a) and t(1/2) changes could be rationalized using the X-ray structures of apo-DHFR, DHFR-MTX-NADPH, and DHFR-folate-NADP+. The availability of the neutron diffraction structure of DHFR-MTX enabled us to compare the protonation states of histidine imidazole rings.Our results demonstrate the usefulness of His-HDX-MS in probing the microenvironments of histidine residues within proteins

Molecular and cellular mechanisms underlying the evolution of form and function in the amniote jaw.

The amniote jaw complex is a remarkable amalgamation of derivatives from distinct embryonic cell lineages. During development, the cells in these lineages experience concerted movements, migrations, and signaling interactions that take them from their initial origins to their final destinations and imbue their derivatives with aspects of form including their axial orientation, anatomical identity, size, and shape. Perturbations along the way can produce defects and disease, but also generate the variation necessary for jaw evolution and adaptation. We focus on molecular and cellular mechanisms that regulate form in the amniote jaw complex, and that enable structural and functional integration. Special emphasis is placed on the role of cranial neural crest mesenchyme (NCM) during the species-specific patterning of bone, cartilage, tendon, muscle, and other jaw tissues. We also address the effects of biomechanical forces during jaw development and discuss ways in which certain molecular and cellular responses add adaptive and evolutionary plasticity to jaw morphology. Overall, we highlight how variation in molecular and cellular programs can promote the phenomenal diversity and functional morphology achieved during amniote jaw evolution or lead to the range of jaw defects and disease that affect the human condition