A Lethal Sequelae of Spinal Infection Complicating Surgery and Radiotherapy for Head and Neck Cancer

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Diffuse large B-cell lymphoma of the central nervous system in mycophenolate mofetil-treated patients with systemic lupus erythematosus

We report the third case of primary lymphoma of the central nervous system (PCNSL) in a patient with systemic lupus erythematosus (SLE) given long-term mycophenolate mofetil (MMF). Our 43-year-old patient has a history of lupus nephritis and has been treated with MMF 500 mg/day in addition to azathioprine (AZA) for 8 years. She presented with subacute left-sided weakness. Magnetic resonance imaging revealed a gadoliniumenhancing mass in the right parietal region which was isointense on T2-weighted imaging. Brain biopsy revealed diffuse sheets of large lymphoid cells which demonstrated strong membranous expression of CD20 by immunohistochemistry and positive signal for Epstein Bar virus (EBV)–encoded RNA by in-situ hybridization study. Complete remission of PCNSL was achieved after discontinuation of MMF and administration of rituximab and whole brain radiotherapy. Patients with SLE are predisposed to development of lymphoma regardless of immunosuppressive use. One meta-analysis found that non-Hodgkin’s lymphoma was more common in SLE patients with a standardized incidence rate ranging from 5.2 to 44.4. However, the development of PCNSL secondary to immunosuppressive use is being increasingly recognised especially in MMF-treated renal transplant recipients with onset of PCNSL after a median of 14 months. It has also been described in some MMF-treated autoimmune conditions such as myasthenia gravis, dermatomyositis and relapsing polychondritis. Although AZA in combination with corticosteroids has been shown to predispose post-renal transplant patients to lymphoproliferative disease with a relative risk of 12.7, the association of AZA and EBV-related lymphoma is rare. The approach to management of this condition includes withdrawal of MMF and judicious use of future immunosuppressive agents.published_or_final_versionThe 15th Medical Research Conference (15th MRC), Department of Medicine, University of Hong Kong, Hong Kong, 16 January 2010. In Hong Kong Medical Journal, 2010, v. 16 n. 1, suppl. 1, p. 54, abstract no. 9

Calycosin and Formononetin Induce Endothelium-Dependent Vasodilation by the Activation of Large-Conductance Ca2+-Activated K+ Channels (BKCa)

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Aquaporin 3 expression in respiratory mucosa is down-regulated in bronchiectasis in vivo

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Anti-inflammatory treatment increased exhaled nitric oxide production on patients with active bronchiectasis

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Kinase Inhibitors for the Treatment of Rheumatoid Arthritis

The use of biologics has been a major advance in the treatment of rheumatoid arthritis over the last decade. However, their need for a parenteral route of administration has made them less desirable for some patients. Efforts have been channelled into the development of oral tyrosine kinase inhibitors, and their results have been promising. This article will provide an overall review of three main tyrosine kinase inhibitors which have been studied for patients with rheumatoid arthritis

A "tricky" subarachnoid hemorrhage

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Diffuse large B-cell lymphoma of the central nervous system in mycophenolate mofetil-treated patients with systemic lupus erythematosus

Patients with systemic lupus erythematosus (SLE) are susceptible to the development of lymphoproliferative disorders and postulated causes include intrinsic defects in immune surveillance and iatrogenic administration of immunosuppressants. Since the introduction of mycophenolate mofetil (MMF) to the immunosuppressive regimen for the management of post-organ transplantation, there have been reports of primary lymphoma of the central nervous system (PCNSL). MMF has been widely used to treat active SLE patients with Class IV lupus nephritis. In addition to two previously reported cases of PCNSL among SLE patients on long-term MMF, we report a third patient who has been on treatment with MMF for 8 years. The histology showed features compatible with diffuse large B-cell lymphoma with strong immunohistochemical staining for CD20 and positive signal for Epstein-Barr virus (EBV)-encoded RNA by in-situ hybridization that is similar to other case reports, suggesting EBV driven B-cell lymphoproliferative disease. The patient responded to withdrawal of MMF, intravenous methotrexate, rituximab and whole brain radiotherapy. With the increasing use of MMF in active renal as well as non-renal exacerbations of SLE, PCNSL should be included in the differential diagnosis in patients who present with gradual onset of focal neurological deficit.link_to_subscribed_fulltex

In vitro study examining the effect of sub-lethal QS 755 nm lasers on the expression of p16INK4a on melanoma cell lines

Background and Objectives: Q-switched lasers had been used in the treatment of lentigo maligna but their role remains controversial. While previous studies have addressed the change in adhesion molecule expression after sub-lethal laser damage, no study has addressed the impact of sub-lethal laser damage at a molecular level. The p16 gene has been proposed as the candidate gene for melanoma. Our objective is to examine the effect of sub-lethal laser damage on p16 expression in melanoma cell lines. Study Design/Materials and Methods: Three human melanoma cell lines - HTB 66, Sk-mel-24 (HTB 71), and G361 - were irradiated by a Q-switched 755 nm Alexandrite laser at fluencies that ranged from 0.85 to 2.0 J/cm2. HTB 66 was the only cell line with significant expression of p16INK4a while the other two cells lines were p16INK4a negative and served as negative control. Protein and mRNA expression for p16 were assessed by flow cytometry and RT-PCR, respectively. Results: The level of p16INK4a protein in cell line HTB 66 increased significantly after laser irradiation as compared with non-irradiated cells. The level of p16INK4a protein did not change in p16INK4a-negative cell lines (Sk-mel-24 and G361). However, there was only a slight increase in the percentage of G0/G1 phase cells. Conclusions: Sub-lethal laser damage could increase DNA damage leading to an increase in p16 expression, and such effect would be particularly undesirable for patients with p16 mutation. Further studies are warranted to examine the role of sub-lethal laser damage in inducing p16 mutation. © 2003 Wiley-Liss, Inc.link_to_subscribed_fulltex