Molecular analysis of the diets of snakes: changes in prey exploitation during development of the rare smooth snake Coronella austriaca

Reptiles are declining in many parts of the world, mainly due to habitat loss and environmental change. A major factor in this is availability of suitable food. For many animals, dietary requirements shift during developmental stages and a habitat will only be suitable for conserving a species if it supports all stages. Conventional methods for establishing diet often rely on visual recognition of morphologically identifiable features of prey in faeces, regurgitation or stomach contents, which suffer from biases and poor resolution of taxa. DNA-based techniques facilitate noninvasive analysis of diet from faeces without these constraints. We tested the hypothesis that diet changes during growth stages of smooth snakes (Coronella austriaca), which have a highly restricted distribution in the UK but are widespread in continental Europe. Small numbers of the sympatric grass snake (Natrix natrix) were analysed for comparison. Faecal samples were collected from snakes and prey DNA analysed using PCR, targeting amphibians, reptiles, mammals and invertebrates. Over 85% of smooth snakes were found to have eaten reptiles and 28% had eaten mammals. Predation on mammals increased with age and was entirely absent among juveniles and subadults. Predation on reptiles did not change ontogenetically. Smooth snakes may, therefore, be restricted to areas of sufficiently high reptile densities to support young snakes

Acquisition of a large virulence plasmid (pINV) promoted temperature-dependent virulence and global dispersal of O96:H19 enteroinvasive Escherichia coli

Enteroinvasive Escherichia coli (EIEC) and Shigella are closely related agents of bacillary dysentery. It is widely viewed that EIEC and Shigella species evolved from E. coli via independent acquisitions of a large virulence plasmid (pINV) encoding a type 3 secretion system (T3SS). Sequence Type (ST)99 O96:H19 E. coli is a novel clone of EIEC responsible for recent outbreaks in Europe and South America. Here, we use 92 whole genome sequences to reconstruct a dated phylogeny of ST99 E. coli, revealing distinct phylogenomic clusters of pINV-positive and -negative isolates. To study the impact of pINV acquisition on the virulence of this clone, we developed an EIEC-zebrafish infection model showing that virulence of ST99 EIEC is thermoregulated. Strikingly, zebrafish infection using a T3SS-deficient ST99 EIEC strain and the oldest available pINV-negative isolate reveals a separate, temperature-independent mechanism of virulence, indicating that ST99 non-EIEC strains were virulent before pINV acquisition. Taken together, these results suggest that an already pathogenic E. coli acquired pINV and that virulence of ST99 isolates became thermoregulated once pINV was acquired

Functional interaction between Env oncogene from Jaagsiekte sheep retrovirus and tumor suppressor Sprouty2

<p>Abstract</p> <p>Background</p> <p>Jaagsiekte sheep retrovirus (JSRV) is a type D retrovirus capable of transforming target cells <it>in vitro </it>and <it>in vivo</it>. The Envelope <it>(Env) </it>gene from JSRV and from related retroviruses can induce oncogenic transformation, although the detailed mechanism is yet to be clearly understood. Host cell factors are envisaged to play a critical determining role in the regulation of <it>Env</it>-mediated cell transformation.</p> <p>Results</p> <p>JSRV <it>Env</it>-mediated transformation of a lung adenocarcinoma cell line induced rapid proliferation, anchorage-independent growth and tumor formation, but completely abrogated the migration ability. An analysis of the signaling scenario in the transformed cells suggested the involvement of the ERK pathway regulated by Sprouty2 in cell migration, and the PI3K-Akt and STAT3 pathways in proliferation and anchorage-independence. On the other hand, in a normal lung epithelial cell line, <it>Env</it>-mediated transformation only decreased the migration potential while the other functions remained unaltered. We observed that <it>Env </it>induced the expression of a tumor suppressor, Sprouty2, suggesting a correlation between <it>Env</it>-effect and Sprouty2 expression. Overexpression of Sprouty2 <it>per se </it>not only decreased the migratory potential and tumor formation potential of the target cells but also made them resistant to subsequent <it>Env</it>-mediated transformation. On the other hand, over expression of the functional mutants of Sprouty2 had no inhibitory effect, confirming the role of Sprouty2 as a tumor suppressor.</p> <p>Conclusions</p> <p>Our studies demonstrate that <it>Env </it>and Sprouty2 have a functional relationship, probably through shared signaling network. Sprouty2 functions as a tumor suppressor regulating oncogenic transformation of cells, and it therefore has the potential to be exploited as a therapeutic anti-cancer agent.</p

Genetic Variation and Aflatoxin Accumulation Resistance among 36 Maize Genotypes Evaluated in Ghana

Aflatoxins are carcinogenic secondary metabolites produced predominantly by the fungi Aspergillus flavus and parasiticus. The toxin contaminate maize grains and threatens human food safety. Survey in Ghana revealed aflatoxin contamination of maize in excess of 941 ppb which is way beyond WHO and USA approved limits of 15 ppb and 20 ppb respectively. Host plant resistance is considered as the best strategy for reducing aflatoxins. This study was designed to (1) identify and select suitable maize lines that combine aflatoxin accumulation resistance and good agronomic traits under tropical conditions and (2) assess the genetic diversity among the exotic and locally adapted maize genotypes using significant morphological traits. Thirty-six maize genotypes, 19 from Mississippi State University, USA and 17 locally adapted genotypes in Ghana were evaluated for aflatoxin accumulation resistance and good agronomic characteristics across six contrasting environments using a 6x6 lattice design with three replicates. Five plants each per genotype were inoculated with a local strain of Aspergillus flavus inoculum at a concentration of 9 x 107/3.4 ml, two weeks after 50% mid silking. Total aflatoxin in the kernels were determined at harvest using HPLC method. Statistical analysis for agronomic traits and aflatoxin levels were performed using PROC GLM procedure implemented in SAS. The result indicated that genotype by environment interaction was significant (p < 0.05) for aflatoxin accumulation resistance and many other agronomic traits. Five genotypes (MP715, NC298, MP705, MP719, CML287 and TZEEI- 24) consistently displayed stable resistance across the environments and may serve as suitable candidates for developing aflatoxin resistant hybrids. Cluster analysis showed two distinct groups (locally adapted and exotic genotypes), an indication of re-cycled alleles per region. Broad sense heritability estimates for grain yield and aflatoxin accumulation resistance were moderately high, which could permit transfer of traits during hybrid development

Publisher Correction: Structural Implications of Mutations Conferring Rifampin Resistance in Mycobacterium leprae.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper

PROJECT MANAGEMENT A PANACEA TO IMPROVING THE PERFORMANCE OF CONSTRUCTION PROJECTS IN OGUN STATE, NIGERIA

The parameters for measuring the performance of project managers on any construction project are time, cost, quality, health and safety, meeting requirements of the owners and satisfaction of stakeholders. This study was conducted in Ogun state to ascertain the effects of project manager on construction works and project delivery in Nigeria. Both qualitative and quantitative data were obtained. A cross-sectional survey research design was used. A survey of randomly selected samples of 32 professionals, questionnaires was used to collect data from Architects, Civil Engineers, Builders and Quantity Surveyors practicing in the state. The result of the findings shows that effective engagement of project managers on project ensures that project criteria are achieved both at the preliminary and construction stages of projects. It is concluded that there is need to engage the services of project managers in projects for better efficiencies and quality delivery of projects. It is however recommended that project managers should be properly trained and engage in continuous professional development to be abreast with latest project management strategie

Intracellular Calcium Disturbances Induced by Arsenic and Its Methylated Derivatives in Relation to Genomic Damage and Apoptosis Induction

Arsenic and its methylated derivatives are contaminants of air, water, and food and are known as toxicants and carcinogens. Arsenic compounds are also being used as cancer chemotherapeutic agents. In humans, inorganic arsenic is metabolically methylated to mono-, di-, and trimethylated forms. Recent findings suggest that the methylation reactions represent a toxification rather than a detoxification pathway. In recent years, the correlation between arsenic exposure, cytotoxicity and genotoxicity, mutagenicity, and tumor promotion has been established, as well as the association of arsenic exposure with perturbation of physiologic processes, generation of reactive oxygen species, DNA damage, and apoptosis induction. Trivalent forms of arsenic have been found to induce apoptosis in several cellular systems with involvement of membrane-bound cell death receptors, activation of caspases, release of calcium stores, and changes of the intracellular glutathione level. It is well known that calcium ion deregulation plays a critical role in apoptotic cell death. A calcium increase in the nuclei might lead to toxic effects in the cell. In this review, we highlight the relationship between induced disturbances of calcium homeostasis, genomic damage, and apoptotic cell death caused by arsenic and its organic derivatives

A human-centered design methodology to enhance the usability, human factors, and user experience of connected health systems: a three-phase methodology.

peer-reviewedDesign processes such as human-centered design, which involve the end user throughout the product development and testing process, can be crucial in ensuring that the product meets the needs and capabilities of the user, particularly in terms of safety and user experience. The structured and iterative nature of human-centered design can often present a challenge when design teams are faced with the necessary, rapid, product development life cycles associated with the competitive connected health industry. We wanted to derive a structured methodology that followed the principles of human-centered design that would allow designers and developers to ensure that the needs of the user are taken into account throughout the design process, while maintaining a rapid pace of development. In this paper, we present the methodology and its rationale before outlining how it was applied to assess and enhance the usability, human factors, and user experience of a connected health system known as the Wireless Insole for Independent and Safe Elderly Living (WIISEL) system, a system designed to continuously assess fall risk by measuring gait and balance parameters associated with fall risk. We derived a three-phase methodology. In Phase 1 we emphasized the construction of a use case document. This document can be used to detail the context of use of the system by utilizing storyboarding, paper prototypes, and mock-ups in conjunction with user interviews to gather insightful user feedback on different proposed concepts. In Phase 2 we emphasized the use of expert usability inspections such as heuristic evaluations and cognitive walkthroughs with small multidisciplinary groups to review the prototypes born out of the Phase 1 feedback. Finally, in Phase 3 we emphasized classical user testing with target end users, using various metrics to measure the user experience and improve the final prototypes. We report a successful implementation of the methodology for the design and development of a system for detecting and predicting falls in older adults. We describe in detail what testing and evaluation activities we carried out to effectively test the system and overcome usability and human factors problems. We feel this methodology can be applied to a wide variety of connected health devices and systems. We consider this a methodology that can be scaled to different-sized projects accordingly.PUBLISHEDpeer-reviewe

Primary tooth abscess caused by Mycobacterium bovis in an immunocompetent child

Bovine tuberculosis is a zoonotic disease, and although its incidence has dramatically decreased in developed countries where effective control measures are applied, it still remains a potential health hazard in the developing world. Tuberculosis of the oral cavity is extremely rare and is usually secondary to pulmonary involvement. We present the unusual case of an immunocompetent 6-year-old child residing in an urban area with primary oral tuberculosis due to Mycobacterium bovis, which was confirmed by the application of a molecular genetic approach. M. bovis belongs to Mycobacterium tuberculosis complex which comprises species with close genetic relationship, and for this reason, the use of new molecular techniques is a useful tool for the differentiation at species level of the closely related members of this complex