HLA-B*2709 and lack of susceptibility to sacroiliitis: further support from the clinic.

Interferons (IFN) are well known triggers of immunomediated diseases in genetically predisposed subjects. We describe the unique case of a HLA-B*2709 positive subject who underwent IFN-alpha treatment for essential thrombocythemia and developed arthritis of the proximal interphalangeal joints of the hands but not sacroiliitis. The possible mechanisms of IFN-induced arthritis are discussed.

[IFN-alpha-induced psoriatic arthritis and HCV-related liver cirrhosis. Therapeutic options and patient's opinion]. / Paziente con cirrosi epatica HCV correlata e sviluppo di artrite psoriasica indotta da IFN-alpha. Opzioni terapeutiche e volontà del paziente.

Hepatitis C virus (HCV) infection in the setting of Psoriatic Arthritis is an additional variable to be considered in the therapeutic approach to the disease because of the complications of an immunosuppressive treatment in the course of a chronic infection and the possible hepatotoxicity of many drugs conventionally used to treat psoriatic arthritis. The case reported explores the therapeutic options in a patient with IFN-alpha-induced psoriatic arthritis, characterised by severe arthritis and psoriasis but also the concomitant presence of HCV chronic hepatitis, in light of the patient's concerns.

Genetics of psoriasis and psoriatic arthritis.

Psoriasis and psoriatic arthritis are linked diseases characterised by (distinct ?) immune-mediated pathogenetic mechanisms and by a genetic background interacting with environmental factors. Some candidate susceptibility genes have been studied extensively; they include HLA genes, genes within the HLA region and genes outside the HLA region; among them corneodesmosin and other genes of PSORS1 region, MICA and TNF-a polymorphisms. The main findings in the literature are discussed.

Regenerative potential of silk conduits in repair of peripheral nerve injury in adult rats.

Various attempts have been made to develop artificial conduits for nerve repair, but with limited success. We describe here conduits made from Bombyx mori regenerated silk protein, and containing luminal fibres of Spidrex(®), a silk-based biomaterial with properties similar to those of spider silk. Assessment in vitro demonstrated that Spidrex(®) fibres support neurite outgrowth. For evaluation in vivo, silk conduits 10 mm in length and containing 0, 100, 200 or 300 luminal Spidrex(®) fibres, were implanted to bridge an 8 mm gap in the rat sciatic nerve. At 4 weeks, conduits containing 200 luminal Spidrex(®) fibres (PN200) supported 62% and 59% as much axon growth as autologous nerve graft controls at mid-conduit and distal nerve respectively. Furthermore, Spidrex(®) conduits displayed similar Schwann cell support and macrophage response to controls. At 12 weeks, animals implanted with PN200 conduits showed similar numbers of myelinated axons (81%) to controls, similar gastrocnemius muscle innervation, and similar hindpaw stance assessed by Catwalk footprint analysis. Plantar skin innervation was 73% of that of controls. PN200 Spidrex(®) conduits were also effective at bridging longer (11 and 13 mm) gaps. Our results show that Spidrex(®) conduits promote excellent axonal regeneration and function recovery, and may have potential for clinical application.

Hemarthrosis as acute presentation of acquired hemophilia in a patient with systemic lupus erythematosus: successful treatment and long-lasting remission.

Hemorrhagic events due to production of antibodies directed against coagulation factors are rarely observed in systemic lupus erythematosus (SLE). We report the case of a patient with clinically quiescent SLE who developed factor VIII inhibitor in acquired hemophilia presenting as hemarthrosis. Initial treatment with FVII, FVIII and FIX plasma concentrate, metilprednisolone and immunoglobulins i.v. were started but new hemorrhagic manifestation occurred. Plasma exchange was also administered, but it was discontinued early due to partial efficacy. In addition, pulse cyclophosphamide 0.5 g/m(2) was started. Eight weeks later, FVIII and FIX activity returned within normal ranges, FVIII and FIX inhibitors decreased significantly and hemorrhagic manifestations disappeared. The rare occurrence of acquired hemophilia due to the presence of anti-factor VIII antibodies associated to SLE, which was reviewed, might explain the lack of therapeutic guide-lines; indeed therapeutic options are available but the outcome in each single patient is not predictable.

The characteristics of neuronal injury in a static compression model of spinal cord injury in adult rats.

Studies of spinal cord injury using contusion (impact) injury paradigms have shown that neuronal death is an acute event that is largely over within 24 h. However, much less is known about cell death following compression injury, despite compression being a key component of natural spinal injuries. We have therefore used neuronal nuclei (NeuN) immunostaining to examine the spatiotemporal pattern of neuronal loss after static compression injury in adult rats. 3D reconstruction was used to reveal the full effect of the injury. Neuronal loss at the injury epicentre, assessed by NeuN immunostaining, amounted to 44% at 1 day but increased to 73% at 3 days and 81% at 1 month. Neuronal loss was also seen 5 mm rostral and caudal to the epicentre, but was not significant until 3 days. NeuN loss was greatest in the ventral horns and in the intermediate grey matter, with the lateral dorsal horns relatively spared. Cystic cavities formed after injury, but were not evident until 4 weeks and were small in size. In contrast to the slow profile of neuronal loss, the compression injury also evoked a transient expression of activating transcription factor-3 (ATF3) and activated c-Jun in neurons. ATF3 expression peaked at 3 days and declined at 7 days. Our spatiotemporal analysis of compression injury shows that neuronal loss is much more protracted than in contusion injury, and highlights the potential for neuroprotective strategies. This study is also the first indication of ATF3 involvement in spinal cord injury.