Improved biocompatibility but limited graft survival after purification of alginate for microencapsulation of pancreatic islets

Graft failure of alginate-polylysine microencapsulated islets is often interpreted as the consequence of a non-specific foreign body reaction against the microcapsules, initiated by impurities present in crude alginate. The aim of the present study was to investigate if purification of the alginate improves the biocompatibility of alginate-polylysine microcapsules. Alginate was purified by filtration, extraction and precipitation. Microcapsules prepared from crude or purified alginate were implanted in the peritoneal cavity of normoglycaemic AO-rats and retrieved at 1, 2, 3, 6, 9, and 12 months after implantation. With crude alginate, all capsules were overgrown within 1 month after implantation. With purified alginate, however, the portion of capsules overgrown was usually less than 10%, even at 12 months after implantation. All recipients of islet allografts in capsules prepared of purified alginate became normoglycaemic within 5 days after implantation, but hyperglycaemia reoccurred after 6 to 20 weeks. With intravenous and oral glucose tolerance test, all recipients had impaired glucose tolerance and insulin responses were virtually absent. After graft failure, capsules were retrieved (80-100%) by peritoneal lavage. Histologically, the percentage of overgrown capsules was usually less than 10% and maximally 31%. This small portion cannot explain the occurrence of graft failure. The immunoprotective properties of the capsules were confirmed by similar if not identical survival times of encapsulated islet allo- and isografts. Our results show that purification of the alginate improves the biocompatibility of alginate-polylysine microcapsules. Nevertheless, graft survival was still limited, most probably as a consequence of a lack of blood supply to the encapsulated islets

Toward a Unified Genetic Map of Higher Plants, Transcending the Monocot-Dicot Divergence

Closely related (confamilial) genera often retain large chromosomal tracts in which gene order is colinear, punctuated by structural mutations such as inversions and translocations 1. To explore the possibility that conservation of gene order might extrapolate to more distantly related taxa, we first estimated an average structural mutation rate. Nine pairs of taxa, for which there exist both comparative genetic maps and plausible estimates of divergence time, showed an average of0.14 (±0.06) structural mutations per chromosome per million years of divergence (Myr; Table 1). This value is offered as a first approximation, acknowledging that refined comparative data and/or divergence estimates may impel revision

Ten Simple Rules for Organizing an Unconference

This is an open access article distributed under the terms of the Creative Commons Attribution License.Peer Reviewe

Accuracy of Protein-Protein Binding Sites in High-Throughput Template-Based Modeling

The accuracy of protein structures, particularly their binding sites, is essential for the success of modeling protein complexes. Computationally inexpensive methodology is required for genome-wide modeling of such structures. For systematic evaluation of potential accuracy in high-throughput modeling of binding sites, a statistical analysis of target-template sequence alignments was performed for a representative set of protein complexes. For most of the complexes, alignments containing all residues of the interface were found. The full interface alignments were obtained even in the case of poor alignments where a relatively small part of the target sequence (as low as 40%) aligned to the template sequence, with a low overall alignment identity (<30%). Although such poor overall alignments might be considered inadequate for modeling of whole proteins, the alignment of the interfaces was strong enough for docking. In the set of homology models built on these alignments, one third of those ranked 1 by a simple sequence identity criteria had RMSD<5 Å, the accuracy suitable for low-resolution template free docking. Such models corresponded to multi-domain target proteins, whereas for single-domain proteins the best models had 5 Å<RMSD<10 Å, the accuracy suitable for less sensitive structure-alignment methods. Overall, ∼50% of complexes with the interfaces modeled by high-throughput techniques had accuracy suitable for meaningful docking experiments. This percentage will grow with the increasing availability of co-crystallized protein-protein complexes

Development of a brief multidisciplinary education programme for patients with osteoarthritis

Background Osteoarthritis (OA) is a prevalent progressive musculoskeletal disorder, leading to pain and disability. Patient information and education are considered core elements in treatment guidelines for OA; however, there is to our knowledge no evidence-based recommendation on the best approach, content or length on educational programmes in OA. Objective: to develop a brief, patient oriented disease specific multidisciplinary education programme (MEP) to enhance self-management in patients with OA. Method Twelve persons (80% female mean age 59 years) diagnosed with hand, hip or knee OA participated in focus group interviews. In the first focus group, six participants were interviewed about their educational needs, attitudes and expectations for the MEP. The interviews were transcribed verbatim and thereafter condensed. Based on results from focus group interviews, current research evidence, clinical knowledge and patients' experience, a multidisciplinary OA team (dietist, nurse, occupational therapist, pharmacist, physical therapist and rheumatologist) and a patient representative developed a pilot-MEP after having attended a work-shop in health pedagogics. Finally, the pilot-MEP was evaluated by a second focus group consisting of four members from the first focus group and six other experienced patients, before final adjustments were made. Results The focus group interviews revealed four important themes: what is OA, treatment options, barriers and coping strategies in performing daily activities, and how to live with osteoarthritis. Identified gaps between patient expectations and experience with the pilot-programme were discussed and adapted into a final MEP. The final MEP was developed as a 3.5 hour educational programme provided in groups of 6-9 patients. All members from the multidisciplinary team are involved in the education programme, including a facilitator who during the provision of the programme ensures that the individual questions are addressed. As part of an ongoing process, a patient representative regularly attends the MEP and gives feedback concerning content and perceived value. Conclusion A MEP has been developed to enhance self-management in patients with OA attending a multidisciplinary OA outpatient clinic. The effectiveness of the MEP followed by individual consultations with members of the multidisciplinary team is currently evaluated in a randomised controlled trial with respect to patient satisfaction and functioning

Control of flowering time and spike development in cereals: the earliness per se Eps-1 region in wheat, rice, and Brachypodium

The earliness per se gene Eps-Am1 from diploid wheat Triticum monococcum affects heading time, spike development, and spikelet number. In this study, the Eps1 orthologous regions from rice, Aegilops tauschii, and Brachypodium distachyon were compared as part of current efforts to clone this gene. A single Brachypodium BAC clone spanned the Eps-Am1 region, but a gap was detected in the A. tauschii physical map. Sequencing of the Brachypodium and A. tauschii BAC clones revealed three genes shared by the three species, which showed higher identity between wheat and Brachypodium than between them and rice. However, most of the structural changes were detected in the wheat lineage. These included an inversion encompassing the wg241-VatpC region and the presence of six unique genes. In contrast, only one unique gene (and one pseudogene) was found in Brachypodium and none in rice. Three genes were present in both Brachypodium and wheat but were absent in rice. Two of these genes, Mot1 and FtsH4, were completely linked to the earliness per se phenotype in the T. monococcum high-density genetic map and are candidates for Eps-Am1. Both genes were expressed in apices and developing spikes, as expected for Eps-Am1 candidates. The predicted MOT1 protein showed amino acid differences between the parental T. monococcum lines, but its effect is difficult to predict. Future steps to clone the Eps-Am1 gene include the generation of mot1 and ftsh4 mutants and the completion of the T. monococcum physical map to test for the presence of additional candidate genes

A Synthetic Adjuvant to Enhance and Expand Immune Responses to Influenza Vaccines

Safe, effective adjuvants that enhance vaccine potency, including induction of neutralizing Abs against a broad range of variant strains, is an important strategy for the development of seasonal influenza vaccines which can provide optimal protection, even during seasons when available vaccines are not well matched to circulating viruses. We investigated the safety and ability of Glucopyranosyl Lipid Adjuvant-Stable Emulsion (GLA-SE), a synthetic Toll-like receptor (TLR)4 agonist formulation, to adjuvant Fluzone® in mice and non-human primates. The GLA-SE adjuvanted Fluzone vaccine caused no adverse reactions, increased the induction of T helper type 1 (TH1)-biased cytokines such as IFNγ, TNF and IL-2, and broadened serological responses against drifted A/H1N1 and A/H3N2 influenza variants. These results suggest that synthetic TLR4 adjuvants can enhance the magnitude and quality of protective immunity induced by influenza vaccines

Coevolution between a Family of Parasite Virulence Effectors and a Class of LINE-1 Retrotransposons

Parasites are able to evolve rapidly and overcome host defense mechanisms, but the molecular basis of this adaptation is poorly understood. Powdery mildew fungi (Erysiphales, Ascomycota) are obligate biotrophic parasites infecting nearly 10,000 plant genera. They obtain their nutrients from host plants through specialized feeding structures known as haustoria. We previously identified the AVRk1 powdery mildew-specific gene family encoding effectors that contribute to the successful establishment of haustoria. Here, we report the extensive proliferation of the AVRk1 gene family throughout the genome of B. graminis, with sequences diverging in formae speciales adapted to infect different hosts. Also, importantly, we have discovered that the effectors have coevolved with a particular family of LINE-1 retrotransposons, named TE1a. The coevolution of these two entities indicates a mutual benefit to the association, which could ultimately contribute to parasite adaptation and success. We propose that the association would benefit 1) the powdery mildew fungus, by providing a mechanism for amplifying and diversifying effectors and 2) the associated retrotransposons, by providing a basis for their maintenance through selection in the fungal genome