Two Crinivirus-specific proteins of Lettuce infectious yellows virus (LIYV), P26 and P9, are self-interacting

Interactions of Lettuce infectious yellows virus (LIYV)-encoded proteins were tested by yeast-two-hybrid (Y2H) assays. LIYV-encoded P34, Hsp70h, P59, CP, CPm, and P26 were tested in all possible pairwise combinations. Interaction was detected only for the P26–P26 combination. P26 self-interaction domains were mapped using a series of N- and C-terminal truncations. Orthologous P26 proteins from the criniviruses Beet pseudoyellows virus (BPYV), Cucurbit yellow stunting disorder virus (CYSDV), and Lettuce chlorosis virus (LCV) were also tested, and each exhibited strong self-interaction but no interaction with orthologous proteins. Two small putative proteins encoded by LIYV RNA2, P5 and P9, were also tested for interactions with the six aforementioned LIYV proteins and each other. No interactions were detected for P5, but P9–P9 self-interaction was detected. P26- and P9-encoding genes are present in all described members of the genus Crinivirus, but are not present in other members of the family Closteroviridae. LIYV P26 has previously been demonstrated to induce a unique LIYV cytopathology, plasmalemma deposits (PLDs), but no role is yet known for P9.     

Analysis of variations in the NAPG gene on chromosome 18p11 in bipolar disorder

OBJECTIVE: A number of studies have implicated the chromosome 18p11 region as a susceptibility region for bipolar disorder. The gene encoding gamma-SNAP (NAPG), one of three soluble N-ethylmaleimide-sensitive fusion (NSF)-attachment proteins (SNAPs), is located in the 18p11 region and is thought to play a role in cellular processes required for neurotransmission in the central nervous system. The purpose of this study is to investigate whether polymorphisms in the human NAPG gene contribute to the etiology of bipolar disorder. METHODS: To test this hypothesis, we used a case-control design in which the genotype and allele frequencies for five single-nucleotide polymorphisms in the human NAPG gene were compared between individuals with a diagnosis of type I bipolar disorder (n=460) and control individuals (n=191). RESULTS: The genotype results indicate that three of the single-nucleotide polymorphisms in the NAPG gene, rs2290279 (P=0.027), rs495484 (P=0.044) and rs510110 (P=0.046), show a nominal, statistically significant association with bipolar disorder at the genotype frequency level. CONCLUSIONS: The results of this study suggest that polymorphisms in the human NAPG gene may represent risk factors for the development of bipolar disorder, but before such a role can be established, the results of this study must be confirmed in additional populations of bipolar disorder patients and controls.     

Design optimization methods for genomic DNA tiling arrays

A recent development in microarray research entails the unbiased coverage, or tiling, of genomic DNA for the large-scale identification of transcribed sequences and regulatory elements. A central issue in designing tiling arrays is that of arriving at a single-copy tile path, as significant sequence cross-hybridization can result from the presence of non-unique probes on the array. Due to the fragmentation of genomic DNA caused by the widespread distribution of repetitive elements, the problem of obtaining adequate sequence coverage increases with the sizes of subsequence tiles that are to be included in the design. This becomes increasingly problematic when considering complex eukaryotic genomes that contain many thousands of interspersed repeats. The general problem of sequence tiling can be framed as finding an optimal partitioning of non-repetitive subsequences over a prescribed range of tile sizes, on a DNA sequence comprising repetitive and non-repetitive regions. Exact solutions to the tiling problem become computationally infeasible when applied to large genomes, but successive optimizations are developed that allow their practical implementation. These include an efficient method for determining the degree of similarity of many oligonucleotide sequences over large genomes, and two algorithms for finding an optimal tile path composed of longer sequence tiles. The first algorithm, a dynamic programming approach, finds an optimal tiling in linear time and space; the second applies a heuristic search to reduce the space complexity to a constant requirement. A Web resource has also been developed, accessible at http://tiling.gersteinlab.org, to generate optimal tile paths from user-provided DNA sequences.     

p38MAPK mediates IL-1-induced down-regulation of aggrecan gene expression in human chondrocytes

The pleiotropic cytokine interleukin 1 (IL-1) is considered to be the principal inducer of mediators of cartilage degradation in both, osteoarthritis (OA) and rheumatoid arthritis (RA). IL-1 activates numerous signaling pathways involved in cartilage destruction and dedifferentiation of chondrocytes. In this study, we analyzed expression and functional effects of IL-1 in human chondrocytes. We found an IL-1-induced reduction in the expression of the cartilage specific proteoglycan aggrecan as an indicator for the IL-1-mediated dedifferentiation of chondrocytes. To block the IL-1-induced signaling pathways specifically, we incubated human chondrocytes and cartilage explants with IL-1 in the presence of different signal transduction inhibitors and analyzed their effect on aggrecan mRNA expression and IL-6 secretion. IL-6 has been found to act synergistically in the IL-1-induced suppression of the proteoglycan synthesis in chondrocytes. Our results led to the identification of p38MAPK and/or PI3K/JNK as being crucial for IL-1-induced IL-6 secretion by chondrocytes. IL-1-induced down-regulation of aggrecan expression was found to be mediated by p38MAPK and/or ERK1/2. The identification and characterization of these signaling pathways will enable us to develop new modulation strategies for therapeutic use in inflammatory joint diseases.     

Activating and inhibitory FcgammaRs in autoimmune disorders

Autoimmune disorders are characterized by the destruction of self-tissues by the immune system. Multiple checkpoints are in place to prevent autoreactivity under normal circumstances. Coexpression of activating and inhibitory Fc receptors (FcR) represents such a checkpoint by establishing a threshold for immune cell activation. In many human autoimmune diseases, however, balanced FcR expression is disturbed. Analysis of murine model systems provides strong evidence that aberrant FcR expression can result in uncontrolled immune responses and the initiation of autoimmune disease. This review will summarize this data and explain how this information might be used to better understand human autoimmune diseases and to develop novel therapeutic strategies.     

Effects of treatment with acamprosate on beta-endorphin plasma concentration in humans with high alcohol preference

Treatment with acamprosate, a compound used for relapse prevention treatment of alcoholism, was recently shown to be associated with increased plasma concentration of beta-endorphin in rats selectively bred for high alcohol preference. The aim of our study was to prove this result in a comparative clinical study with a corresponding design. We studied 51 alcohol dependent patients following alcohol withdrawal during treatment with acamprosate versus placebo for 4 weeks. Data were analyzed for patients with high alcohol preference (HP) and low alcohol preference (LP) by dichotomizing the sample according to median alcohol intake prior to detoxification. In line with pre-clinical data, beta-endorphin plasma concentration in HP patients was significantly lower compared with LP patients. Four weeks of treatment with acamprosate resulted in a significantly increased beta-endorphin plasma concentration compared with placebo and a significant difference in HP patients but not in LP patients. In conclusion, acamprosate seems to modulate the endogenous opioid system. Our data are in accordance with the assumption that the effect of acamprosate on endorphin plasma concentrations is mainly based on the effect in the high preferring subgroup. Since beta-endorphin deficiency was earlier associated with alcohol craving and anxiety during withdrawal, abstinence maintaining effects of acamprosate might at least be partially related with the ability to modulate opioidergic activity especially in the subsample of HP patients with an attenuated opioidergic activity during this state.     

Impaired clearance of apoptotic cardiocytes is linked to anti-SSA/Ro and -SSB/La antibodies in the pathogenesis of congenital heart block

The role of cardiocytes in physiologic removal of apoptotic cells and the subsequent effect of surface binding by anti-SSA/Ro and -SSB/La antibodies was addressed. Initial experiments evaluated induction of apoptosis by extrinsic and intrinsic pathways. Nuclear injury and the translocation of SSA/Ro and SSB/La antigens to the fetal cardiocyte plasma membrane were common downstream events of Fas and TNF receptor ligation, requiring caspase activation. As assessed by phase-contrast and confirmed by confocal microscopy, coculturing of healthy cardiocytes with cardiocytes rendered apoptotic via extrinsic pathways revealed a clearance mechanism that to our knowledge has not previously been described. Cultured fetal cardiocytes expressed phosphatidylserine receptors (PSRs), as did cardiac tissue from a fetus with congenital heart block (CHB) and an age-matched control. Phagocytic uptake was blocked by anti-PSR antibodies and was significantly inhibited following preincubation of apoptotic cardiocytes with chicken and murine anti-SSA/Ro and -SSB/La antibodies, with IgG from an anti-SSA/Ro- and -SSB/La-positive mother of a CHB child, but not with anti-HLA class I antibody. In a murine model, anti-Ro60 bound and inhibited uptake of apoptotic cardiocytes from wild-type but not Ro60-knockout mice. Our results suggest that resident cardiocytes participate in physiologic clearance of apoptotic cardiocytes but that clearance is inhibited by opsonization via maternal autoantibodies, resulting in accumulation of apoptotic cells, promoting inflammation and subsequent scarring.     

Pathology and protection in nephrotoxic nephritis is determined by selective engagement of specific Fc receptors

Introduction of heterologous anti-glomerular basement membrane antiserum (nephrotoxic serum, NTS) into presensitized mice triggers the production of IgG anti-NTS antibodies that are predominantly IgG2b and the glomerular deposition of pathogenic immune complexes, leading to accelerated renal disease. The pathology observed in this model is determined by the effector cell activation threshold that is established by the coexpression on infiltrating macrophages of the IgG2a/2b restricted activation receptor FcgammaRIV and its inhibitory receptor counterpart, FcgammaRIIB. Blocking FcgammaRIV with a specific monoclonal antibody thereby preventing IgG2b engagement or treatment with high dose intravenous gamma-globulin (IVIG) to down-regulate FcgammaRIV while up-regulating FcgammaRIIB, protects mice from fatal disease. In the absence of FcgammaRIIB, IVIG is not protective; this indicates that reduced FcgammaRIV expression alone is insufficient to protect animals from pathogenic IgG2b immune complexes. These results establish the significance of specific IgG subclasses and their cognate FcgammaRs in renal disease.     

A Clinical phase I/II trial to investigate preoperative dose-escalated intensity-modulated radiation therapy (IMRT) and intraoperative radiation therapy (IORT) in patients with retroperitoneal soft tissue sarcoma

ABSTRACT: BACKGROUND: Local control rates in patients with retroperitoneal soft tissue sarcoma (RSTS) remain disappointing even after gross total resection, mainly because wide margins are not achievable in the majority of patients. In contrast to extremity sarcoma, postoperative radiation therapy (RT) has shown limited efficacy due to its limitations in achievable dose and coverage. Although Intraoperative Radiation Therapy (IORT) has been introduced in some centers to overcome the dose limitations and resulted in increased outcome, local failure rates are still high even if considerable treatment related toxicity is accepted. As postoperative administration of RT has some general disadvantages, neoadjuvant approaches could offer benefits in terms of dose escalation, target coverage and reduction of toxicity, especially if highly conformal techniques like intensity-modulated radiation therapy (IMRT) are considered. METHODS: The trial is a prospective, one armed, single center phase I/II study investigating a combination of neoadjuvant dose-escalated IMRT (50-56 Gy) followed by surgery and IORT (10-12 Gy) in patients with at least marginally resectable RSTS. The primary objective is the local control rate after five years. Secondary endpoints are progression-free and overall survival, acute and late toxicity, surgical resectability and patterns of failure. The aim of accrual is 37 patients in the per-protocol population. DISCUSSION: The present study evaluates combined neoadjuvant dose-escalated IMRT followed by surgery and IORT concerning its value for improved local control without markedly increased toxicity. Trial Registration : NCT01566123.     

Use of antimalarials in dermatology

The antimalarials chloroquine and hydroxychloroquine have been used for the treatment of inflammatory diseases for more than 60 years. Even today new indications evolve due to the complex mode of action of these compounds. Due to the fear of side effects, especially irreversible retinopathy, their use is often limited. These side‐effects, however, are a consequence of excessive daily dosages. An effective, safe therapy needs correct dosing, i. e. adherence to maximal daily dosages of 3.5(–4) mg chloroquine or 6(–6.5) mg hydroxychloroquine per kilogram ideal body weight. If the actual body weight is lower than the ideal body weight, this actual weight is used for the calculation of the dosage. Observing these limits allows a rather safe therapy of the diseases like lupus erythematosus, REM syndrome, porphyria cutanea tarda (2 × 125 mg chloroquine/week), cutaneous sarcoidosis and dermatomyositis. If standard therapies fail, then antimalarials can be tried to treat Sjögren syndrome, granu‐loma annulare or erosive lichen planus. If therapy fails, either can be combined with quinacrine to increase their effectiveness. Chloroquine and hydroxychloroquine are indispensable and well‐tolerated essential drugs in dermatology and especially suited as part of a combination scheme, for example with corticosteroids, as they act synergistically and reduce side‐effects.