The relationship between regional variations in blood flow and histology in a transplanted rat fibrosarcoma

The regional distribution of blood flow to the LBDS1 fibrosarcoma, transplanted into the subcutaneous site in rats, was investigated using the readily diffusible compound 14C-iodo-antipyrine (14C-IAP). Quantitative autoradiography was used to establish absolute values of specific blood flow F for 100 X 100 X 20 microns adjacent tissue volumes of the unperturbed tumour. Mean blood flow to whole tumours was found to decrease with increase in tumour size. This relationship was abolished if blood flow was only measured in sections cut from the periphery of the tumours. Detailed analysis of a sub-group of tumours showed that blood flow to individual tumours was heterogeneous. The range of blood flow was large, indicating that mean blood flow to a whole tumour is a poor reflection of the blood perfusion pattern of that tumour. Necrotic tumour regions were usually very poorly perfused. With the exception of the smallest tumours studied, blood flow was lower in the centre of tumours than in the periphery. Necrosis also tended to develop centrally. However, the peripheral to central gradient of blood flow was apparent even when densely cellular, viable tumour regions and necrotic regions were analysed separately. The decrease in blood flow with tumour size was also apparent in densely cellular, viable tumour regions when analysed separately. Qualitative comparison of tumour histology and regional blood flow showed that there were areas of very low blood flow associated with viable tumour regions. Less common were areas of rather high blood flow associated with necrotic tumour regions. A complicated relationship exists between tumour histology and blood flow. The quantitative autoradiography technique is suitable for investigating the most poorly perfused and the most well perfused viable fractions of animal tumours which may limit the efficacy of different types of therapy

Raman Spectroscopic Analysis of Geological and Biogeological Specimens of Relevance to the ExoMars Mission

H.G.M.E., I.H., and R.I. acknowledge the support of the STFC Research Council in the UK ExoMars programme. J.J. and P.V. acknowledge the support of the Grant Agency of the Czech Republic (210/10/0467) and of the Ministry of Education of the Czech Republic (MSM0021620855).Peer reviewedPublisher PD

Plasmacytoid Dendritic Cells Are Productively Infected and Activated through TLR-7 Early after Arenavirus Infection.

The antiviral response is largely mediated by dendritic cells (DCs), including conventional (c) DCs that function as antigen-presenting cells, and plasmacytoid (p) DCs that produce type I interferons, making them an attractive target for viruses. We find that the Old World arenaviruses lymphocytic choriomeningitis virus clone 13 (LCMV Cl13) and Lassa virus bind pDCs to a greater extent than cDCs. Consistently, LCMV Cl13 targets pDCs early after in vivo infection of its natural murine host and establishes a productive and robust replication cycle. pDCs coproduce type I interferons and proinflammatory cytokines, with the former being induced in both infected and uninfected pDCs, demonstrating a dissociation from intrinsic virus replication. TLR7 globally mediates pDC responses, limits pDC viral load, and promotes rapid innate and adaptive immune cell activation. These early events likely help dictate the outcome of infections with arenaviruses and other DC-replicating viruses and shed light on potential therapeutic targets

A model structure for coloured operads in symmetric spectra

We describe a model structure for coloured operads with values in the category of symmetric spectra (with the positive model structure), in which fibrations and weak equivalences are defined at the level of the underlying collections. This allows us to treat R-module spectra (where R is a cofibrant ring spectrum) as algebras over a cofibrant spectrum-valued operad with R as its first term. Using this model structure, we give suficient conditions for homotopical localizations in the category of symmetric spectra to preserve module structures.Comment: 16 page

Rat-to-Human Transmission of Cowpox Infection

We isolated Cowpox virus (CPXV) from the ulcerative eyelid lesions of a 14-year-old girl, who had cared for a clinically ill wild rat that later died. CPXV isolated from the rat (Rattus norvegicus) showed complete homology with the girl’s virus. Our case is the first proven rat-to-human transmission of cowpox

Discussion and debates in Pacific education

A collection of papers based on twelve presentations delivered as part of the School of Education's Talanga Seminar Series, at the University of the South Pacific

The use of yeast inoculation in fermentation for port production; effect on total potential ethyl carbamate

A commercial wine yeast Saccharomyces cerevisiae UCD 522 (pre-cultured in the presence of certain mass-labelled amino acids) was inoculated into a port must which was then allowed to ferment under controlled conditions of temperature and agitation. The influence of potential ethyl carbamate (EC) precursor formed due to yeast pre-culture, upon total potential EC levels was studied at various stages of fermentation. Pre-culture accumulation did not give rise to detectable levels of EC precursor during port fermentation

Diffusion of gold nanoclusters on graphite

We present a detailed molecular-dynamics study of the diffusion and coalescence of large (249-atom) gold clusters on graphite surfaces. The diffusivity of monoclusters is found to be comparable to that for single adatoms. Likewise, and even more important, cluster dimers are also found to diffuse at a rate which is comparable to that for adatoms and monoclusters. As a consequence, large islands formed by cluster aggregation are also expected to be mobile. Using kinetic Monte Carlo simulations, and assuming a proper scaling law for the dependence on size of the diffusivity of large clusters, we find that islands consisting of as many as 100 monoclusters should exhibit significant mobility. This result has profound implications for the morphology of cluster-assembled materials

The extent and effectiveness of protected areas in the UK

The Convention on Biological Diversity (CBD), to which 196 countries including the UK are contracting parties, set out 20 Aichi Biodiversity Targets to be met by 2020. Elements of Aichi Target 11 call for at least 17% of terrestrial land and inland water to be protected and effectively managed by 2020. Each national government is requested to report progress against this goal in national reports submitted at intervals to the CBD, and these are used as the basis of reporting towards the 17% target. Figures reported for the UK’s protected area coverage are inclusive of a wide range of levels of designation, management and condition. Here, we examine the protection given to sites under UK legislation and designations as a case study. We find that although 28% of UK land is reported by the UK government to be protected, only 11.4% of land area falls within protected areas designated primarily for nature conservation. Condition monitoring indicates that at most 43–51% of protected areas in the UK are currently in favourable condition, which suggests as little as 4.9% of UK land area may be effectively protected for nature. However, estimates of protected area coverage vary greatly depending on the types of protected areas considered ‘effectively protected’ as measured by management category and site condition. Taking the UK as an example of a country that has reportedly met the target, we suggest that global progress may have been overestimated, and that future targets and indicators need to focus on the quality as well as quantity of protected areas