Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0014070 (encephalomyelitis)
 13,017 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This review examines the efficacy of photodynamic therapy in the treatment of immunological disorders. Photodynamic therapy (PDT) is a 2-step procedure. Firstly, a photosensitiser is introduced into the body, where it accumulates selectively in cells with elevated metabolism, such as cancer cells or activated cells of the immune system. Second, light is applied at a wavelength that excites the photosensitiser, producing a variety of short-lived oxygen-derived species. The effect is dependent on the doses of both photosensitiser and activating light. The mechanisms of action of PDT are multifactorial. Induction of high levels of oxidative stress results in necrotic cell death, while lower intensity oxidative stress initiates apoptosis. Sublethal doses may result in the modification of cell surface receptor expression levels and cytokine release and consequently influence cell behaviour. Immunomodulatory PDT (IPDT) utilises mainly apoptotic and sublethal doses. The studies reported here utilise verteporfin, a benzoporphyrin-derived chlorin-like photosensitiser. Veteporfin is a second generation photosensitiser, displaying rapid clearance and consequently a reduced period of skin photosensitivity compared with the first generation photosensitiser, porfimer sodium. In vivo studies showed that IPDT was effective in alleviating immunopathology in murine models of arthritis, contact hypersensitivity, experimental allergic encephalomyelitis and retention of allogeneic skin grafts. Based on these findings, early stage clinical trials with IPDT were initiated recently for the treatment of psoriasis, psoriatic arthritis and rheumatoid arthritis. While verteporfin has been the photosensitiser which pioneered IPDT, a new benzoporphyrin derivative photosensitiser, QLT0074, is under development. This has demonstrated an enhanced avidity for target cells as well as improved clearance characteristics.
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PMID:Photodynamic therapy in immune (non-oncological) disorders: focus on benzoporphyrin derivatives. 1803 64

Paraneoplastic retinopathy including cancer-associated retinopathy (CAR) and melanoma-associated retinopathy (MAR), and paraneoplastic optic neuropathy (PON) are visual disorders associated with systemic cancer. Patients with CAR typically present with progressive loss of vision and photopsia, which are related to dysfunction of both cones and rods in photoreceptors. The triad of photosensitivity, ring scotoma, and a reduced caliber of the retinal arteriole along with undetectable signals in electroretinogram (ERG) are specific manifestations of CAR. CAR is associated most commonly with small-cell lung cancer (SCLC) and occasionally with gynecologic tumors, and it is usually caused by autoantibodies against recovering, which is a calcium-binding photoreceptor protein that participates in the transduction of light. MAR is characterized by shimmering, flickering, or pulsating photopsias, and usually occurs in the patients with a cutaneous melanoma. MAR differs from CAR in terms of visual acuity and color vision and is associated with a characteristic pattern detected in ERG. Autoantibodies against the bipolar cells of the retina have been identified in patients with MAR. Patients with PON frequently present with progressive visual loss and optic disc edema, or with other paneoplastic neurologic syndromes related to SCLC, such as paraneoplastic encephalomyelitis or retinitis, ophthalmoplegia, and subacute cerebellar syndrome. Autoantibodies against collapsin-responsive mediator protein-5 (CRMP-5, also called anti-CV2) are considered to be as the causative factor. Treatments with corticosteroids, plasma exchange, and intravenous immune globulin as well as treatment of the tumor itself, occasionally improves these paraneoplastic visual syndromes. However, the prognosis depends on their underlying malignancy.
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PMID:[Paraneoplastic retinopathy and optic neuropathy]. 2042 Jan 77