Sub-lethal radiation enhances anti-tumor immunotherapy in a transgenic mouse model of pancreatic cancer

BACKGROUND: It is not uncommon to observe circulating tumor antigen-specific T lymphocytes in cancer patients despite a lack of significant infiltration and destruction of their tumors. Thus, an important goal for tumor immunotherapy is to identify ways to modulate in vivo anti-tumor immunity to achieve clinical efficacy. We investigate this proposition in a spontaneous mouse tumor model, Rip1-Tag2. METHODS: Experimental therapies were carried out in two distinctive trial designs, intended to either intervene in the explosive growth of small tumors, or regress bulky end-stage tumors. Rip1-Tag2 mice received a single transfer of splenocytes from Tag-specific, CD4(+) T cell receptor transgenic mice, a single sub-lethal radiation, or a combination therapy in which the lymphocyte transfer was preceded by the sub-lethal radiation. Tumor burden, the extent of lymphocyte infiltration into solid tumors and host survival were used to assess the efficacy of these therapeutic approaches. RESULTS: In either intervention or regression, the transfer of Tag-specific T cells alone did not result in significant lymphocyte infiltration into solid tumors, not did it affect tumor growth or host survival. In contrast, the combination therapy resulted in significant reduction in tumor burden, increase in lymphocyte infiltration into solid tumors, and extension of survival. CONCLUSIONS: The results indicate that certain types of solid tumors may be intrinsically resistant to infiltration and destruction by tumor-specific T lymphocytes. Our data suggest that such resistance can be disrupted by sub-lethal radiation. The combinatorial approach presented here merits consideration in the design of clinical trials aimed to achieve T cell-mediated anti-tumor immunity

Transcriptome sequencing of lentil based on second-generation technology permits large-scale unigene assembly and SSR marker discovery

<p>Abstract</p> <p>Background</p> <p>Lentil (<it>Lens culinaris </it>Medik.) is a cool-season grain legume which provides a rich source of protein for human consumption. In terms of genomic resources, lentil is relatively underdeveloped, in comparison to other Fabaceae species, with limited available data. There is hence a significant need to enhance such resources in order to identify novel genes and alleles for molecular breeding to increase crop productivity and quality.</p> <p>Results</p> <p>Tissue-specific cDNA samples from six distinct lentil genotypes were sequenced using Roche 454 GS-FLX Titanium technology, generating c. 1.38 × 10⁶expressed sequence tags (ESTs). <it>De novo </it>assembly generated a total of 15,354 contigs and 68,715 singletons. The complete unigene set was sequence-analysed against genome drafts of the model legume species <it>Medicago truncatula </it>and <it>Arabidopsis thaliana </it>to identify 12,639, and 7,476 unique matches, respectively. When compared to the genome of <it>Glycine max</it>, a total of 20,419 unique hits were observed corresponding to c. 31% of the known gene space. A total of 25,592 lentil unigenes were subsequently annoated from GenBank. Simple sequence repeat (SSR)-containing ESTs were identified from consensus sequences and a total of 2,393 primer pairs were designed. A subset of 192 EST-SSR markers was screened for validation across a panel 12 cultivated lentil genotypes and one wild relative species. A total of 166 primer pairs obtained successful amplification, of which 47.5% detected genetic polymorphism.</p> <p>Conclusions</p> <p>A substantial collection of ESTs has been developed from sequence analysis of lentil genotypes using second-generation technology, permitting unigene definition across a broad range of functional categories. As well as providing resources for functional genomics studies, the unigene set has permitted significant enhancement of the number of publicly-available molecular genetic markers as tools for improvement of this species.</p

Search for rare quark-annihilation decays, B --> Ds(*) Phi

We report on searches for B- --> Ds- Phi and B- --> Ds*- Phi. In the context of the Standard Model, these decays are expected to be highly suppressed since they proceed through annihilation of the b and u-bar quarks in the B- meson. Our results are based on 234 million Upsilon(4S) --> B Bbar decays collected with the BABAR detector at SLAC. We find no evidence for these decays, and we set Bayesian 90% confidence level upper limits on the branching fractions BF(B- --> Ds- Phi) Ds*- Phi)<1.2x10^(-5). These results are consistent with Standard Model expectations.Comment: 8 pages, 3 postscript figues, submitted to Phys. Rev. D (Rapid Communications

Characterization of Rhodamine-123 as a Tracer Dye for Use In In vitro Drug Transport Assays

Fluorescent tracer dyes represent an important class of sub-cellular probes and allow the examination of cellular processes in real-time with minimal impact upon these processes. Such tracer dyes are becoming increasingly used for the examination of membrane transport processes, as they are easy-to-use, cost effective probe substrates for a number of membrane protein transporters. Rhodamine 123, a member of the rhodamine family of flurone dyes, has been used to examine membrane transport by the ABCB1 gene product, MDR1. MDR1 is viewed as the archetypal drug transport protein, and is able to efflux a large number of clinically relevant drugs. In addition, ectopic activity of MDR1 has been associated with the development of multiple drug resistance phenotype, which results in a poor patient response to therapeutic intervention. It is thus important to be able to examine the potential for novel compounds to be MDR1 substrates. Given the increasing use rhodamine 123 as a tracer dye for MDR1, a full characterisation of its spectral properties in a range of in vitro assay-relevant media is warranted. Herein, we determine λmax for excitation and emission or rhodamine 123 and its metabolite rhodamine 110 in commonly used solvents and extraction buffers, demonstrating that fluorescence is highly dependent on the chemical environment: Optimal parameters are 1% (v/v) methanol in HBSS, with λex = 505 nm, λem = 525 nm. We characterise the uptake of rhodamine 123 into cells, via both passive and active processes, and demonstrate that this occurs primarily through OATP1A2-mediated facilitated transport at concentrations below 2 µM, and via micelle-mediated passive diffusion above this. Finally, we quantify the intracellular sequestration and metabolism of rhodamine 123, demonstrating that these are both cell line-dependent factors that may influence the interpretation of transport assays

An inquiry into good hospital governance: A New Zealand-Czech comparison

BACKGROUND: This paper contributes to research in health systems literature by examining the role of health boards in hospital governance. Health care ranks among the largest public sectors in OECD countries. Efficient governance of hospitals requires the responsible and effective use of funds, professional management and competent governing structures. In this study hospital governance practice in two health care systems – Czech Republic and New Zealand – is compared and contrasted. These countries were chosen as both, even though they are geographically distant, have a universal right to 'free' health care provided by the state and each has experienced periods of political change and ensuing economic restructuring. Ongoing change has provided the impetus for policy reform in their public hospital governance systems. METHODS: Two comparative case studies are presented. They define key similarities and differences between the two countries' health care systems. Each public hospital governance system is critically analysed and discussed in light of D W Taylor's nine principles of 'good governance'. RESULTS: While some similarities were found to exist, the key difference between the two countries is that while many forms of 'ad hoc' hospital governance exist in Czech hospitals, public hospitals in New Zealand are governed in a 'collegiate' way by elected District Health Boards. These findings are discussed in relation to each of the suggested nine principles utilized by Taylor. CONCLUSION: This comparative case analysis demonstrates that although the New Zealand and Czech Republic health systems appear to show a large degree of convergence, their approaches to public hospital governance differ on several counts. Some of the principles of 'good governance' existed in the Czech hospitals and many were practiced in New Zealand. It would appear that the governance styles have evolved from particular historical circumstances to meet each country's specific requirements. Whether or not current practice could be improved by paying closer attention to theoretical models of 'good governance' is debatable

Lack of effective communication between communities and hospitals in Uganda: a qualitative exploration of missing links

<p>Abstract</p> <p>Background</p> <p>Community members are stakeholders in hospitals and have a right to participate in the improvement of quality of services rendered to them. Their views are important because they reflect the perspectives of the general public. This study explored how communities that live around hospitals pass on their views to and receive feedback from the hospitals' management and administration.</p> <p>Methods</p> <p>The study was conducted in eight hospitals and the communities around them. Four of the hospitals were from three districts from eastern Uganda and another four from two districts from western Uganda. Eight key informant interviews (KIIs) were conducted with medical superintendents of the hospitals. A member from each of three hospital management boards was also interviewed. Eight focus group discussions (FGDs) were conducted with health workers from the hospitals. Another eight FGDs (four with men and four with women) were conducted with communities within a five km radius around the hospitals. Four of the FGDs (two with men and two with women) were done in western Uganda and the other four in eastern Uganda. The focus of the KIIs and FGDs was exploring how hospitals communicated with the communities around them. Analysis was by manifest content analysis.</p> <p>Results</p> <p>Whereas health unit management committees were supposed to have community representatives, the representatives never received views from the community nor gave them any feed back from the hospitals. Messages through the mass media like radio were seen to be non specific for action. Views sent through suggestion boxes were seen as individual needs rather than community concerns. Some community members perceived they would be harassed if they complained and had reached a state of resignation preferring instead to endure the problems quietly.</p> <p>Conclusion</p> <p>There is still lack of effective communication between the communities and the hospitals that serve them in Uganda. This deprives the communities of the right to participate in the improvement of the services they receive, to assume their position as stakeholders. Various avenues could be instituted including using associations in communities, rapid appraisal methods and community meetings.</p

Reconstruction of metabolic pathways for the cattle genome

<p>Abstract</p> <p>Background</p> <p>Metabolic reconstruction of microbial, plant and animal genomes is a necessary step toward understanding the evolutionary origins of metabolism and species-specific adaptive traits. The aims of this study were to reconstruct conserved metabolic pathways in the cattle genome and to identify metabolic pathways with missing genes and proteins. The MetaCyc database and PathwayTools software suite were chosen for this work because they are widely used and easy to implement.</p> <p>Results</p> <p>An amalgamated cattle genome database was created using the NCBI and Ensembl cattle genome databases (based on build 3.1) as data sources. PathwayTools was used to create a cattle-specific pathway genome database, which was followed by comprehensive manual curation for the reconstruction of metabolic pathways. The curated database, CattleCyc 1.0, consists of 217 metabolic pathways. A total of 64 mammalian-specific metabolic pathways were modified from the reference pathways in MetaCyc, and two pathways previously identified but missing from MetaCyc were added. Comparative analysis of metabolic pathways revealed the absence of mammalian genes for 22 metabolic enzymes whose activity was reported in the literature. We also identified six human metabolic protein-coding genes for which the cattle ortholog is missing from the sequence assembly.</p> <p>Conclusion</p> <p>CattleCyc is a powerful tool for understanding the biology of ruminants and other cetartiodactyl species. In addition, the approach used to develop CattleCyc provides a framework for the metabolic reconstruction of other newly sequenced mammalian genomes. It is clear that metabolic pathway analysis strongly reflects the quality of the underlying genome annotations. Thus, having well-annotated genomes from many mammalian species hosted in BioCyc will facilitate the comparative analysis of metabolic pathways among different species and a systems approach to comparative physiology.</p

Henipavirus RNA in African Bats

BACKGROUND: Henipaviruses (Hendra and Nipah virus) are highly pathogenic members of the family Paramyxoviridae. Fruit-eating bats of the Pteropus genus have been suggested as their natural reservoir. Human Henipavirus infections have been reported in a region extending from Australia via Malaysia into Bangladesh, compatible with the geographic range of Pteropus. These bats do not occur in continental Africa, but a whole range of other fruit bats is encountered. One of the most abundant is Eidolon helvum, the African Straw-coloured fruit bat. METHODOLOGY/PRINCIPAL FINDINGS: Feces from E. helvum roosting in an urban setting in Kumasi/Ghana were tested for Henipavirus RNA. Sequences of three novel viruses in phylogenetic relationship to known Henipaviruses were detected. Virus RNA concentrations in feces were low. CONCLUSIONS/SIGNIFICANCE: The finding of novel putative Henipaviruses outside Australia and Asia contributes a significant extension of the region of potential endemicity of one of the most pathogenic virus genera known in humans

Crucial Role for BAFF-BAFF-R Signaling in the Survival and Maintenance of Mature B Cells

Defects in the expression of either BAFF (B cell activating factor) or BAFF-R impairs B cell development beyond the immature, transitional type-1 stage and thus, prevents the formation of follicular and marginal zone B cells, whereas B-1 B cells remain unaffected. The expression of BAFF-R on all mature B cells might suggest a role for BAFF-R signaling also for their in vivo maintenance. Here, we show that, 14 days following a single injection of an anti-BAFF-R mAb that prevents BAFF binding, both follicular and marginal zone B cell numbers are drastically reduced, whereas B-1 cells are not affected. Injection of control, isotype-matched but non-blocking anti-BAFF-R mAbs does not result in B cell depletion. We also show that this depletion is neither due to antibody-dependent cellular cytotoxicity nor to complement-mediated lysis. Moreover, prevention of BAFF binding leads to a decrease in the size of the B cell follicles, an impairment of a T cell dependent humoral immune response and a reduction in the formation of memory B cells. Collectively, these results establish a central role for BAFF-BAFF-R signaling in the in vivo survival and maintenance of both follicular and marginal zone B cell pools