Mid- to long-term success rate and functional outcomes of acromioclavicular injections in patients with acromioclavicular osteoarthritis

Background Acromioclavicular (AC) osteoarthritis (OA) is a frequent pathology of the shoulder in elderly patients. Drug injection plays an important role in treatment of AC OA. Literature has demonstrated excellent short-term results regarding shoulder function and pain. However, mid- to long-term results are lacking. The aim of this study was to assess the efficacy of a single intra-articular AC injection in patients with AC OA and to identify predictive factors for success. Methods A retrospective study was performed to analyze success rate, shoulder function, and pain perception after a single intra-articular injection in patients with AC OA. Success was defined as the absence of reinterventions such as additional injection or surgery. Outcome measures were 1-year success rate and clinical outcome scores of Numeric Rating Scale (NRS) for pain, Oxford Shoulder Score, and Subjective Shoulder Value. Results Ninety-eight patients participated in this study. At a median final follow-up of 0.8 years (interquartile range, 0–6), 57 of these patients (58%) had undergone a reintervention. The 1-year success rate was 47% (95% confidence interval, 37%–57%), with NRS at rest as the sole factor significantly associated with success. Thirty patients not requiring reintervention reported significant improvement from baseline for all reported outcome measures at final follow-up. Conclusions AC injections offer a 1-year success rate of 47%. The AC injection produces good mid- to long-term clinical outcomes regarding shoulder function, quality of life, and pain perception in one-third of patients. Further research is essential to analyze mid- to long-term outcomes of AC injections. Level of evidenceLevel IV

High resolution mapping of a novel late blight resistance gene Rpi-avll, from the wild Bolivian species Solanum avilesii

Both Mexico and South America are rich in Solanum species that might be valuable sources of resistance (R) genes to late blight (Phytophthora infestans). Here, we focus on an R gene present in the diploid Bolivian species S. avilesii. The genotype carrying the R gene was resistant to eight out of 10 Phytophthora isolates of various provenances. The identification of a resistant phenotype and the generation of a segregating population allowed the mapping of a single dominant R gene, Rpi-avl1, which is located in an R gene cluster on chromosome 11. This R gene cluster is considered as an R gene “hot spot”, containing R genes to at least five different pathogens. High resolution mapping of the Rpi-avl1 gene revealed a marker co-segregating in 3890 F1 individuals, which may be used for marker assisted selection in breeding programs and for further cloning of Rpi-avl

Broad spectrum late blight resistance in potato differential set plants MaR8 and MaR9 is conferred by multiple stacked R genes

Phytophthora infestans is the causal agent of late blight in potato. The Mexican species Solanum demissum is well known as a good resistance source. Among the 11 R gene differentials, which were introgressed from S. demissum, especially R8 and R9 differentials showed broad spectrum resistance both under laboratory and under field conditions. In order to gather more information about the resistance of the R8 and R9 differentials, F1 and BC1 populations were made by crossing Mastenbroek (Ma) R8 and R9 clones to susceptible plants. Parents and offspring plants were examined for their pathogen recognition specificities using agroinfiltration with known Avr genes, detached leaf assays (DLA) with selected isolates, and gene-specific markers. An important observation was the discrepancy between DLA and field trial results for Pi isolate IPO-C in all F1 and BC1 populations, so therefore also field trial results were included in our characterization. It was shown that in MaR8 and MaR9, respectively, at least four (R3a, R3b, R4, and R8) and seven (R1, Rpi-abpt1, R3a, R3b, R4, R8, R9) R genes were present. Analysis of MaR8 and MaR9 offspring plants, that contained different combinations of multiple resistance genes, showed that R gene stacking contributed to the Pi recognition spectrum. Also, using a Pi virulence monitoring system in the field, it was shown that stacking of multiple R genes strongly delayed the onset of late blight symptoms. The contribution of R8 to this delay was remarkable since a plant that contained only the R8 resistance gene still conferred a delay similar to plants with multiple resistance genes, like, e.g., cv Sarpo Mira. Using this “de-stacking” approach, many R gene combinations can be made and tested in order to select broad spectrum R gene stacks that potentially provide enhanced durability for future application in new late blight resistant varieties

Exploitation of Herpesvirus Immune Evasion Strategies to Modify the Immunogenicity of Human Mesenchymal Stem Cell Transplants

BACKGROUND: Mesenchymal stem cells (MSCs) are multipotent cells residing in the connective tissue of many organs and holding great potential for tissue repair. In culture, human MSCs (hMSCs) are capable of extensive proliferation without showing chromosomal aberrations. Large numbers of hMSCs can thus be acquired from small samples of easily obtainable tissues like fat and bone marrow. MSCs can contribute to regeneration indirectly by secretion of cytokines or directly by differentiation into specialized cell types. The latter mechanism requires their long-term acceptance by the recipient. Although MSCs do not elicit immune responses in vitro, animal studies have revealed that allogeneic and xenogeneic MSCs are rejected. METHODOLOGY/PRINCIPAL FINDINGS: We aim to overcome MSC immune rejection through permanent down-regulation of major histocompatibility complex (MHC) class I proteins on the surface of these MHC class II-negative cells through the use of viral immune evasion proteins. Transduction of hMSCs with a retroviral vector encoding the human cytomegalovirus US11 protein resulted in strong inhibition of MHC class I surface expression. When transplanted into immunocompetent mice, persistence of the US11-expressing and HLA-ABC-negative hMSCs at levels resembling those found in immunodeficient (i.e., NOD/SCID) mice could be attained provided that recipients' natural killer (NK) cells were depleted prior to cell transplantation. CONCLUSIONS/SIGNIFICANCE: Our findings demonstrate the potential utility of herpesviral immunoevasins to prevent rejection of xenogeneic MSCs. The observation that down-regulation of MHC class I surface expression renders hMSCs vulnerable to NK cell recognition and cytolysis implies that multiple viral immune evasion proteins are likely required to make hMSCs non-immunogenic and thereby universally transplantable

Optical tweezers in concentrated colloidal dispersions : Manipulating and imaging individual particles

Using a laser beam that is focused down to a diffraction-limited spot, particles with a size ranging from several nanometers up to tens of micrometers can be trapped and manipulated. This technique, known as "optical tweezers" or "optical trapping", has been used in a wide variety of (interdisciplinary) fields and its use is expanding fast. Recent improvements allow for new exciting and promising applications. First an introduction to the technique of optical tweezers is given and the setup that combines optical tweezers with confocal microscopy is described. By time-sharing a single laser beam, hundreds of optical traps can be created and changed dynamically. Independent three-dimensional trapping and imaging of individual particles is possible because two microscope objectives are used, one below and one above the sample. We demonstrate that large two-dimensional patterns of colloidal particles can be created using optical tweezers by positioning particles on a coated surface. These structures of colloidal particles can subsequently be used as masks for colloidal lithography. These masks can be modified further using ion beam deformation or, alternatively, chemical methods. Large arrays of metal nanoparticles with sizes in the range of tens of nanometers have been created using these techniques. Using our setup we have also studied crystallization and melting in colloidal dispersions. A single optical trap was used on collections of particles to crystallize two- and three-dimensional colloidal dispersions. With specially synthesized mixtures of core-shell colloidal particles it is now possible to manipulate individual articles selectively inside concentrated dispersions. Arrays of optical tweezers were used to trap core-shell particles that act as nuclei for homogeneous and heterogeneous nucleation in concentrated colloidal dispersions. We show a single particle driven through a three-dimensional colloidal crystal

Reflective programming in the relational algebra

This paper introduces a reflective extension of the relational algebra. Reflection is achieved by storing and manipulating relational algebra programs as relations and by adding a LISP-like evaluation operation to the algebra. We first show that this extension, which we call the reflective algebra, can serve as a unifying formalization of various forms of procedural data management which have been considered in database systems research. We then study the expressive power and complexity of the reflective algebra. In particular, we establish a close correspondence between reflection and bounded looping, and between tailrecursive reflection and unbounded looping. These correspondences yield new logical characterizations of PTIME and PSPACE.] 1996 Academic Press, Inc. 1