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A response surface methodology (RSM) approach is applied to optimise the temperature-programme gas-chromatographic separation of 16 organochloride pesticides, including 12 compounds identified as highly toxic chemicals by the Stockholm Convention on Persistent Organic Pollutants. A three-parameter relationship describing both linear and curve temperature programmes is derived adapting a model previously used in literature to describe concentration gradients in liquid chromatography with binary eluents. To investigate the influence of the three temperature profile descriptors (the starting temperature, the gradient duration and a shape parameter), a three-level full-factorial design of experiments is used to identify suitable combinations of the above variables spanning over a useful domain. Resolutions of adjacent peaks are the responses modelled by RSM using two alternative methods: a multi-layer artificial network (ANN) and usual polynomial regression. The proposed ANN-based approach permits to model simultaneously the resolutions of all the consecutive analyte pairs as a function of the temperature profile descriptors. Four critical pairs giving partially overlapped peaks are identified and multiresponse optimisation is carried out by analysing the surface plot of a global resolution defined as the average of the resolutions of the critical pairs. Descriptive/predictive performance and applicability of the ANN and polynomial RSM methods are compared and discussed., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Objectives: The objectives of this study are to review our current knowledge of the aetiopathogenesis of Vogt-Koyanagi-Harada syndrome, including viral infection, genetic factors and immunomediated mechanisms, and to discuss pathogenesis and its relevance to pharmacotherapy., Systematic Review Methodology: Relevant publications from 1965 to 2012 on the aetiopathogenesis and pharmacotherapy of VKHS were analysed., Results and Conclusion: Vogt-Koyanagi-Harada syndrome (VKHS) is a rare multisystemic autoimmune disease that affects tissues containing melanin, including the eye, inner ear, meninges, and skin. The disease is characterised by bilateral uveitis associated with a varying constellation of auditory, neurological and cutaneous manifestations. The disease occurs more frequently among people with darker skin pigmentation. Asians, Native Americans, and Hispanics are most frequently affected. It predominates in patients aged between 20 and 50years, and females are affected more frequently, with a female:male ratio of 2:1. The classic clinical course is characterised by bilateral panuveitis, hypoacusis, and meningitis, in addition to cutaneous involvement with poliosis, vitiligo, and alopecia. Although the exact cause of VKH disease remains unknown, it is thought to be a T-cell-mediated autoimmune process directed against melanocytes. VKHS classically begins with vague systemic symptoms suggestive of a viral infection, although a clear association between a specific viral agent and the disease has not been established. Genetic factors may play an important role in the loss of self-tolerance in VKHS. The HLA-DRB1*0405 allele is the main susceptibility allele for VKHS. Early and aggressive systemic corticosteroids are still the primary initial therapy for VKHS. Ocular complications may require an intravitreous injection of corticosteroids. Despite proper treatment with steroids, a number of patients experience recurrent attacks or steroid-associated complications. Thus, non steroid immunomodulatory therapy (IMT) has become necessary for the treatment of VKHS., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Objectives: The objective of our study was to review our current knowledge of the aetiopathogenesis of Cogan's syndrome, including viral infection and autoimmunity, and to discuss disease pathogenesis with relevance to pharmacotherapy., Systematic Review Methodology: Relevant publications on the aetiopathogenesis and pharmacotherapy of Cogan's syndrome from 1945 to 2012 were analysed., Results and Conclusions: Cogan's syndrome is a rare autoimmune vasculitis, and its pathogenesis is unknown. Infection, but primarily autoimmunity, may play contributing roles in the pathogenesis of this disease. It is characterised by ocular and audiovestibular symptoms similar to those of Meniere's syndrome. Approximately 70% of patients have systemic disease, of which vasculitis is considered the pathological mechanism. The immunologic theory is based on the release of auto-antibodies against corneal, inner ear and endothelial antigens, and of anti-nuclear cytoplasmic auto-antibodies (ANCA). Corticosteroids are the first line of treatment, and multiple immunosuppressive drugs have been tried with varying degrees of success. Tumour necrosis factor (TNF)-alpha blockers are a category of immunosuppressive agents representing a recent novel therapeutic option in Cogan's syndrome., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Objectives: To review our current knowledge of the etiopathogenesis of Bell's palsy, including viral infection or autoimmunity, and to discuss disease pathogenesis with respect to pharmacotherapy., Systematic Review Methodology: Relevant publications on the etiopathogenesis, clinical presentation, diagnosis and histopathology of Bell's palsy from 1975 to 2012 were analysed., Results and Conclusions: Bell's palsy is an idiopathic peripheral nerve palsy involving the facial nerve. It accounts for 60 to 75% of all cases of unilateral facial paralysis. The annual incidence of Bell's palsy is 15 to 30 per 100,000 people. The peak incidence occurs between the second and fourth decades (15 to 45 years). The aetiology of Bell's palsy is unknown but viral infection or autoimmune disease has been postulated as possible pathomechanisms. Bell's palsy may be caused when latent herpes viruses (herpes simplex, herpes zoster) are reactivated from cranial nerve ganglia. A cell-mediated autoimmune mechanism against a myelin basic protein has been suggested for the pathogenesis of Bell's palsy. Bell's palsy may be an autoimmune demyelinating cranial neuritis, and in most cases, it is a mononeuritic variant of Guillain-Barré syndrome, a neurologic disorder with recognised cell-mediated immunity against peripheral nerve myelin antigens. In Bell's palsy and GBS, a viral infection or the reactivation of a latent virus may provoke an autoimmune reaction against peripheral nerve myelin components, leading to the demyelination of cranial nerves, especially the facial nerve. Given the safety profile of acyclovir, valacyclovir, and short-course oral corticosteroids, patients who present within three days of the onset of symptoms should be offered combination therapy. However it seems logical that in fact, steroids exert their beneficial effect via immunosuppressive action, as is the case in some other autoimmune disorders. It is to be hoped that (monoclonal) antibodies and/or T-cell immunotherapy might provide more specific treatment guidelines in the management of Bell's palsy., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Objectives: To review our current knowledge of the pathogenesis of Meniere's disease, including viral infection and immune system-mediated mechanisms, and to discuss the pathogenesis as it relates to pharmacotherapy., Systematic Review Methodology: Relevant publications on the aetiopathogenesis, molecular biology, genetics and histopathology of Meniere's disease from 1861 to 2011 were analysed., Results and Conclusions: Meniere's disease is characterised by intermittent episodes of vertigo, fluctuating sensorineural hearing loss, tinnitus, and aural pressure. The aetiology and pathogenesis remain unknown. Proposed theories of causation include viral infections and immune system-mediated mechanisms. The immune response in Meniere's disease is focused on inner ear antigens. Approximately one-third of Meniere's disease cases seem to be of an autoimmune origin although the immunological mechanisms involved are not clear. The diagnosis of autoimmune inner ear disease is based either on clinical criteria or on a positive response to steroids. The antiviral approach has virtually eliminated the use of various surgical methods used in the past. Steroid responsiveness is high, and with prompt treatment, inner ear damage may be reversible. The administration of etanercept improves or stabilises symptoms in treated patients. Treatment of antiphospholipid syndrome can be directed toward preventing thromboembolic events by using antithrombotic medications. Only warfarin has been shown to be effective. Gene therapy can be used to transfer genetic material into inner ear cells using viral vectors and to protect, rescue, and even regenerate hair cells of the inner ear., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Objectives: To review our current knowledge of the pathogenesis of sudden sensorineural hearing loss, including viral infection, vascular occlusion and immune system-mediated mechanisms, and to discuss the pathogenesis as it relates to pharmacotherapy., Systematic Review Methodology: Relevant publications on the pathogenesis of sudden sensorineural hearing loss from 1944 to 2010 were analysed., Results and Conclusions: Sudden sensorineural hearing loss is defined as hearing loss of 30 dB in three sequential frequencies over 3 days or less. It can be an isolated symptom or the presenting symptom of a systemic disease. The aetiology and pathogenesis remain unknown. Detailed investigation typically reveals a specific cause in about 10% of patients. Proposed theories of causation include viral infections, vascular occlusion and immune system-mediated mechanisms. A variety of therapies have been proposed based on the various proposed aetiologies., (Copyright © 2011 Elsevier B.V. All rights reserved.)