A Tachyglossid-Like Humerus from the Early Cretaceous of South-Eastern Australia

A partial right humerus has been recovered from the Early Cretaceous (Albian) Eumeralla Formation at Dinosaur Cove in south-eastern Australia. General morphology, size and the presence of a single epicondylar foramen (the entepicondylar) suggest that the bone is from a mammal or an advanced therapsid reptile. The humerus is similar in size, shape and torsion to the equivalent bone of extant and late Neogene echidnas (Tachyglossidae) but, contrary to the situation in extant monotremes, in which the ulna and radius articulate with a single, largely bulbous condyle, it bears a shallow, pulley-shaped (i.e. trochlear-form) ulnar articulation that is confluent ventro-laterally with the bulbous radial condyle. This form of ulnar articulation distinguishes this bone from the humeri of most advanced therapsids and members of several major groups of Mesozoic mammals, which have a condylar ulnar articulation, but parallels the situation found in therian mammals and in some other lineages of Mesozoic mammals. As in extant monotremes the distal humerus is greatly expanded transversely and humeral torsion is strong. Transverse expansion of the distal humerus is evident in the humeri of the fossorial docodont Haldanodon, highly-fossorial talpids and some clearly fossorial dicynodont therapsids, but the fossil shows greatest overall similarity to extant monotremes and it is possible that the peculiar elbow joint of extant monotremes evolved from a condition approximating that of the fossil. On the basis of comparisons with Mesozoic and Cainozoic mammalian taxa in which humeral morphology is known, the Dinosaur Cove humerus is tentatively attributed to a monotreme. However, several apparently primitive features of the bone exclude the animal concerned from the extant families Tachyglossidae and Ornithorhynchidae and suggest that, if it is a monotreme, it is a stem-group monotreme. Whatever, the animal's true affinity, the gross morphology of its humerus indicates considerable capacity for rotation-thrust digging.     

Review of genes in development: re-reading the molecular paradigm

Genes in Development is a collection of 13 stimulating essays on "post genomic" approaches to the concept of the gene. At the risk of caricaturing some complex balances, the contributors tend to be skeptical about genetic determinism, the central dogma of molecular biology, reductionism, genes as programs and the concept of the gene as a DNA sequence. They tend to like emergent properties, complexity theory, the parity thesis for developmental resources, developmental systems theory, and membranes. But within this broad weltanschauung the essays in Genes in Development vary widely in their interests and emphases––from the history of twentieth century genetics to the social and ethical issues raised by contemporary genetics––which makes for an attractive and valuable collection.     

A proteinase inhibitor from Nicotiana alata inhibits the normal development of light-brown apple moth, Epiphyas postvittana in transgenic apple plants

Insecticidal proteins are a potential resource to enhance resistance to insect pests in transgenic plants. Here, we describe the generation and analysis of the apple cultivar ‘Royal Gala’ transgenic for Nicotiana alata (N. alata) proteinase inhibitor (PI) and the impact of this PI on the growth and development of the Epiphyas postvittiana (light-brown apple moth). A cDNA clone encoding a proteinase inhibitor precursor from N. alata (Na-PI) under the control of either a double 35S promoter or a promoter from a ribulose-1,5-bisphosphate carboxylase small sub-unit gene (rbcS-E9 promoter) was stably incorporated into ‘Royal Gala’ apple using Agrobacterium-mediated transformation. A 40.3 kDa Na-PI precursor protein was expressed and correctly processed into 6-kDa proteinase inhibitors in the leaves of transgenic apple lines. The 6-kDa polypeptides accumulated to levels of 0.05 and 0.1% of the total soluble protein under the control of the rbc-E9 promoter and the double 35S promoter, respectively. Light-brown apple moth larvae fed with apple leaves expressing Na-PI had significantly reduced body weight after 7 days of feeding and female pupae were 19–28% smaller than controls. In addition, morphological changes such as pupal cases attached to the wing, deformed wings, deformed body shape, and pupal cases and curled wings attached to a deformed body were observed in adults that developed from larvae fed with apple leaves expressing Na-PI, when compared to larvae fed with the non-transformed apple leaves.     

The effects of turbidity, prey density and environmental complexity on the feeding of juvenile Murray cod Maccullochella peelii

Juvenile Murray cod Maccullochella peelii exhibited a type II functional response while preying on blackworms Lumbriculus variegatus, and the parameters of the type II model did not differ significantly between clear (0 NTU) and turbid (150 NTU) treatments. Further experiments showed that vision may not be necessary for prey detection and capture by juvenile M. peelii; consumption of inanimate prey was not significantly different between light and dark (<1 × 10(-4) μE m(-2) s(-1)) trials. These results imply that the sensory physiology of M. peelii is well adapted to a turbid visual environment. In addition, habitat complexity increased the food consumption rate of juvenile M. peelii, perhaps by relaxing innate predator avoidance behaviours that depress foraging in more open environments.     

Mortality risk prediction of high-sensitivity C-reactive protein in suspected acute coronary syndrome: A cohort study

BackgroundThere is limited evidence on the use of high-sensitivity C-reactive protein (hsCRP) as a biomarker for selecting patients for advanced cardiovascular (CV) therapies in the modern era. The prognostic value of mildly elevated hsCRP beyond troponin in a large real-world cohort of unselected patients presenting with suspected acute coronary syndrome (ACS) is unknown. We evaluated whether a mildly elevated hsCRP (up to 15 mg/L) was associated with mortality risk, beyond troponin level, in patients with suspected ACS.Methods and findingsWe conducted a retrospective cohort study based on the National Institute for Health Research Health Informatics Collaborative data of 257,948 patients with suspected ACS who had a troponin measured at 5 cardiac centres in the United Kingdom between 2010 and 2017. Patients were divided into 4 hsCRP groups (<2, 2 to 4.9, 5 to 9.9, and 10 to 15 mg/L). The main outcome measure was mortality within 3 years of index presentation. The association between hsCRP levels and all-cause mortality was assessed using multivariable Cox regression analysis adjusted for age, sex, haemoglobin, white cell count (WCC), platelet count, creatinine, and troponin.Following the exclusion criteria, there were 102,337 patients included in the analysis (hsCRP <2 mg/L (n = 38,390), 2 to 4.9 mg/L (n = 27,397), 5 to 9.9 mg/L (n = 26,957), and 10 to 15 mg/L (n = 9,593)). On multivariable Cox regression analysis, there was a positive and graded relationship between hsCRP level and mortality at baseline, which remained at 3 years (hazard ratio (HR) (95% CI) of 1.32 (1.18 to 1.48) for those with hsCRP 2.0 to 4.9 mg/L and 1.40 (1.26 to 1.57) and 2.00 (1.75 to 2.28) for those with hsCRP 5 to 9.9 mg/L and 10 to 15 mg/L, respectively. This relationship was independent of troponin in all suspected ACS patients and was further verified in those who were confirmed to have an ACS diagnosis by clinical coding. The main limitation of our study is that we did not have data on underlying cause of death; however, the exclusion of those with abnormal WCC or hsCRP levels >15 mg/L makes it unlikely that sepsis was a major contributor.ConclusionsThese multicentre, real-world data from a large cohort of patients with suspected ACS suggest that mildly elevated hsCRP (up to 15 mg/L) may be a clinically meaningful prognostic marker beyond troponin and point to its potential utility in selecting patients for novel treatments targeting inflammation.Trial registrationClinicalTrials.gov - {"type":"clinical-trial","attrs":{"text":"NCT03507309","term_id":"NCT03507309"}}NCT03507309

Amit Kaura and colleagues investigate whether mildly elevated high sensitivity C-reactive protein is associated with mortality risk in patients with suspected acute coronary syndromes.     

Similarity and differences in the Lactobacillus acidophilus group identified by polyphasic analysis and comparative genomics

A set of lactobacilli were investigated by polyphasic analysis. Multilocus sequence analysis, DNA typing, microarray analysis, and in silico whole-genome alignments provided a remarkably consistent pattern of similarity within the Lactobacillus acidophilus complex. On microarray analysis, 17 and 5% of the genes from Lactobacillus johnsonii strain NCC533 represented variable and strain-specific genes, respectively, when tested against four independent isolates of L. johnsonii. When projected on the NCC533 genome map, about 10 large clusters of variable genes were identified, and they were enriched around the terminus of replication. A quarter of the variable genes and two-thirds of the strain-specific genes were associated with mobile DNA. Signatures for horizontal gene transfer and modular evolution were found in prophages and in DNA from the exopolysaccharide biosynthesis cluster. On microarray hybridizations, Lactobacillus gasseri strains showed a shift to significantly lower fluorescence intensities than the L. johnsonii test strains, and only genes encoding very conserved cellular functions from L. acidophilus hybridized to the L. johnsonii array. In-silico comparative genomics showed extensive protein sequence similarity and genome synteny of L. johnsonii with L. gasseri, L. acidophilus, and Lactobacillus delbrueckii; moderate synteny with Lactobacillus casei; and scattered X-type sharing of protein sequence identity with the other sequenced lactobacilli. The observation of a stepwise decrease in similarity between the members of the L. acidophilus group suggests a strong element of vertical evolution in a natural phylogenetic group. Modern whole-genome-based techniques are thus a useful adjunct to the clarification of taxonomical relationships in problematic bacterial groups.     

Systems Analysis of Auxin Transport in the Arabidopsis Root Apex

Auxin is a key regulator of plant growth and development. Within the root tip, auxin distribution plays a crucial role specifying developmental zones and coordinating tropic responses. Determining how the organ-scale auxin pattern is regulated at the cellular scale is essential to understanding how these processes are controlled. In this study, we developed an auxin transport model based on actual root cell geometries and carrier subcellular localizations. We tested model predictions using the DII-VENUS auxin sensor in conjunction with state-of-the-art segmentation tools. Our study revealed that auxin efflux carriers alone cannot create the pattern of auxin distribution at the root tip and that AUX1/LAX influx carriers are also required. We observed that AUX1 in lateral root cap (LRC) and elongating epidermal cells greatly enhance auxin’s shootward flux, with this flux being predominantly through the LRC, entering the epidermal cells only as they enter the elongation zone. We conclude that the nonpolar AUX1/LAX influx carriers control which tissues have high auxin levels, whereas the polar PIN carriers control the direction of auxin transport within these tissues.     

Ontogeny of feeding in two native and one alien fish species from the Murray-Darling Basin, Australia

Investigations into the feeding of the early stages of fishes can provide insights into processes influencing recruitment. In this study, we examined ontogenetic changes in morphology and feeding behaviour of two native Australian freshwater species, Murray cod, Maccullochella peelii peelii, and golden perch, Macquaria ambigua, and the alien species, common carp, Cyprinus carpio. Murray cod free embryos are large and well developed at the onset of feeding, whereas the other two species begin exogenous feeding much younger and are smaller and less-developed. Carp commence exogenous feeding 3 days earlier than golden perch, and show more advanced development of the eyes and ingestive apparatus. We conducted feeding experiments, presenting larvae of the three species with a standardised prey mix (comprising equal numbers of small calanoid copepods, large calanoid copepods, small Daphnia, and large Daphnia). Larvae of most tested ages and species showed a preference for mid-sized prey (300–500 μm wide). This was true even when their gapes substantially exceeded the largest prey offered. Daphnia were consumed more than similar-sized copepods. The results of this study suggest that survival through their larval period will be threatened in all three species if catchable prey <500 μm in width are not available throughout such time. They also suggest that interspecific competition for prey may occur, especially when larvae are very young. The precocious development of structures involved in feeding and the extended transition from endogenous to exogenous feeding of early carp larvae are likely to have contributed to the success of this species since its introduction to Australia.