Development of a sustained-release voriconazole-containing thermogel for subconjunctival injection in horses

PURPOSE. To determine in vitro release profiles, transcorneal permeation, and ocular injection characteristics of a voriconazole-containing thermogel suitable for injection into the subconjunctival space (SCS). METHODS. In vitro release rate of voriconazole (0.3% and 1.5%) from poly (DL-lactide-coglycolide-b-ethylene glycol-b-DL-lactide-co-glycolide) (PLGA-PEG-PLGA) thermogel was determined for 28 days. A Franz cell diffusion chamber was used to evaluate equine transcorneal and transscleral permeation of voriconazole (1.5% topical solution, 0.3% and 1.5% voriconazole-thermogel) for 24 hours. Antifungal activity of voriconazole released from the 1.5% voriconazole-thermogel was determined via the agar disk diffusion method. Ex vivo equine eyes were injected with liquid voriconazole-thermogel (4°C). Distension of the SCS was assessed ultrasonographically and macroscopically. SCS voriconazole-thermogel injections were performed in a horse 1 week and 2 hours before euthanasia and histopathologic analysis of ocular tissues performed. RESULTS. Voriconazole was released from the PLGA-PEG-PLGA thermogel for more than 21 days in all groups. Release followed first-order kinetics. Voriconazole diffused through the cornea and sclera in all groups. Permeation was greater through the sclerae than corneas. Voriconazole released from the 1.5% voriconazole-thermogel showed antifungal activity in vitro. Voriconazole-thermogel was easily able to be injected into the dorsal SCS where it formed a discrete gel deposit. Voriconazole-thermogel was easily injected in vivo and did not induce any adverse reactions. CONCLUSIONS. Voriconazole-containing thermogels have potential application in treatment of keratomycosis. Further research is required to evaluate their performance in vivo

Does the perception of fairness and standard of care in the health system depend on the field of study? Results of an empirical analysis

Background: The main challenge in the context of health care reforms and priority setting is the establishment and/or maintenance of fairness and standard of care. For the political process and interdisciplinary discussion, the subjective perception of the health care system might even be as important as potential objective criteria. Of special interest are the perceptions of academic disciplines, whose representatives act as decision makers in the health care sector. The aim of this study is to explore and compare the subjective perception of fairness and standard of care in the German health care system among students of medicine, law, economics, philosophy, and religion. Methods: Between October 2011 and January 2012, we asked freshmen and advanced students of the fields mentioned above to participate in a paper and pencil survey. Prior to this, we formulated hypotheses. The data were analysed by micro econometric regression techniques. Results: Data from 1,088 students were included in the study. Medical students, freshmen, and advanced students perceive the standard of care significantly as being better than non-medical students. Differences in the perception of fairness are not significant between the freshmen of the academic disciplines; however, they increase with the number of study terms. Besides the field of study, further variables such as gender and health status have a significant impact on perceptions. Conclusions: Our results show that there are differences in the perception of fairness and standard of care between academic disciplines, which might influence the interdisciplinary discussion on health care reforms and priority setting.Leibniz University Hannover/Wege in die Forschung I

The Diffusion of IT in Higher Education: Publishing Productivity of Academic Life Scientists

This study investigates widening access to the Internet and other advancements in IT across institutions of higher education and how these advances have affected the publishing productivity of academic life scientists. What distinguishes this study is that institutional IT access is measured across a wide range of institutions and multiple IT indicators are considered: 1) the adoption of BITNET; 2) the registration of domain names (DNS); 3) the availability of the electronic journal database, JSTOR; and 4) the availability of electronic library resources. Data on life scientists are drawn from the 1983, 1995, 2001, and 2003 Survey of Doctorate Recipients. Universities and colleges are classified into several tiers, depending upon research intensity. Three hypotheses are tested: 1) IT enhances the careers of faculty, independent of tier; 2) IT improves the careers of faculty at lower-tiered relative to higher-tiered institutions; and 3) within tier, the IT revolution increases women’s publication rates relative to their male counterparts. The study finds that the diffusion of IT in higher education follows the standard S-curve, with highertiere

Direct Measurements of the Convective Recycling of the Upper Troposphere

We present a statistical representation of the aggregate effects of deep convection on the chemistry and dynamics of the Upper Troposphere (UT) based on direct aircraft observations of the chemical composition of the UT over the Eastern United States and Canada during summer. These measurements provide new and unique observational constraints on the chemistry occurring downwind of convection and the rate at which air in the UT is recycled, previously only the province of model analyses. These results provide quantitative measures that can be used to evaluate global climate and chemistry models

High-affinity CD8 variants enhance the sensitivity of pMHCI antigen recognition via low-affinity TCRs

The recognition of cell surface presented peptide-Major Histocompatibility Complex Class I (pMHCI) molecules by CD8 T-cells involves cooperative binding of the T-cell receptor (TCR) and CD8 co-receptor. CD8 T-cell antigen specificity is conferred by the TCR, whilst CD8 acts to stabilize the TCR/pMHCI complex and enhance T-cell antigen sensitivity. Earlier work has shown that the sensitivity of antigen recognition can be regulated in vitro by altering the strength of the pMHCI/CD8 interaction. Here, we characterize two CD8 variants with an enhanced affinity for MHCI that remains below the affinity threshold at which non-specific activation is observed. In model systems, expression of these CD8 variants preferentially enhanced pMHCI antigen recognition in the context of low-affinity TCRs. When combined with MHCI-restricted TCRs in primary CD4 T-cells, high affinity CD8 variants could improve T-cell functionality, without loss of antigen specificity. In primary CD8 T-cells, the introduction of high affinity CD8 enhanced T-cell activation compared to endogenous CD8 expression only, although we observed that the introduction of transgenic wild-type CD8 into primary CD8 T-cells also resulted in a similar T-cell effector function enhancement. Collectively, these findings could provide a generically applicable and immediately translatable strategy to augment the therapeutic efficacy of clinically relevant TCRs, which are already being delivered alongside wild-type CD8

Evidence for Reductive Genome Evolution and Lateral Acquisition of Virulence Functions in Two Corynebacterium pseudotuberculosis Strains

Ruiz JC, D'Afonseca V, Silva A, et al. Evidence for Reductive Genome Evolution and Lateral Acquisition of Virulence Functions in Two Corynebacterium pseudotuberculosis Strains. PLoS ONE. 2011;6(4): e18551.Background: Corynebacterium pseudotuberculosis, a Gram-positive, facultative intracellular pathogen, is the etiologic agent of the disease known as caseous lymphadenitis (CL). CL mainly affects small ruminants, such as goats and sheep; it also causes infections in humans, though rarely. This species is distributed worldwide, but it has the most serious economic impact in Oceania, Africa and South America. Although C. pseudotuberculosis causes major health and productivity problems for livestock, little is known about the molecular basis of its pathogenicity. Methodology and Findings: We characterized two C. pseudotuberculosis genomes (Cp1002, isolated from goats; and CpC231, isolated from sheep). Analysis of the predicted genomes showed high similarity in genomic architecture, gene content and genetic order. When C. pseudotuberculosis was compared with other Corynebacterium species, it became evident that this pathogenic species has lost numerous genes, resulting in one of the smallest genomes in the genus. Other differences that could be part of the adaptation to pathogenicity include a lower GC content, of about 52%, and a reduced gene repertoire. The C. pseudotuberculosis genome also includes seven putative pathogenicity islands, which contain several classical virulence factors, including genes for fimbrial subunits, adhesion factors, iron uptake and secreted toxins. Additionally, all of the virulence factors in the islands have characteristics that indicate horizontal transfer. Conclusions: These particular genome characteristics of C. pseudotuberculosis, as well as its acquired virulence factors in pathogenicity islands, provide evidence of its lifestyle and of the pathogenicity pathways used by this pathogen in the infection process. All genomes cited in this study are available in the NCBI Genbank database (http://www.ncbi.nlm.nih.gov/genbank/) under accession numbers CP001809 and CP001829