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P M van Hagen

Publications and source records attributed to P M van Hagen.

At least 19 recordsLinked to original sources
PubMed2006

[Behçet's disease and the possibilities of modern tumour necrosis factor inhibiting medication].

A 25-year-old woman was admitted after having had a fever for one month, headache, nausea, vomiting, dysarthria and right-sided hemiparesis. A 35-year-old man was admitted because of severe loss of vision and a history of focal retinochoroiditis. Both were suffering from Behçet's disease. Behçet's disease can present with systemic symptoms that might be related to aberrant T-cell functions. It is treated with a variety of immunoregulatory drugs. Recently, treatment with tumour necrosis factor (TNF) alpha-inhibiting molecular designed drugs such as infliximab or etanercept has improved the therapeutic prospective of Behçet patients. Both of the patients described above developed refractory disease and responded to treatment with these new drugs.

Adult↗
PubMed2005

The effect of etanercept on Graves' ophthalmopathy: a pilot study.

PURPOSE: To assess the effect of etanercept, an antitumour necrosis factor (anti-TNF) drug, on clinical signs in Graves' ophthalmopathy (GO). METHODS: A total of 10 consecutive patients (seven female, three male) with recent-onset, active, mildly-to-moderately severe GO were treated with subcutaneous injections of 25 mg etanercept (Enbrel) twice weekly during 12 weeks. The average age was 50 years (range: 39-59 years). The average duration of GO was 4 months (range: 2-6 months). All patients were at least 2 months euthyroid with medication. The mean pretreatment clinical activity score (CAS) was 4 (range: 3-6). RESULTS: The mean CAS prior to treatment was 4, at 6 weeks 2.6, and at 12 weeks 1.6. The mean ophthalmopathy index (OI) prior to treatment was 5.8, at 6 weeks 4.8, and at 12 weeks 4.4. Thus, after 12 weeks of treatment the mean CAS had decreased by 2.4+/-1.3 (60%), and the mean OI had decreased by 1.4+/-1.2 (24%). The main decrease of the CAS and OI was noted at 6 weeks of treatment. The difference was particularly evident on soft-tissue changes, including periocular chemosis and redness. The mean exophthalmometry values did not change. In all, 60% percent of patients reported moderate to marked improvement. In three patients, the GO flared up again after cessation of treatment. There were no serious adverse events or side effects during a mean follow-up time of 18 months. CONCLUSIONS: This study strongly suggests that etanercept may suppress the clinical signs in GO, but randomized controlled trials are needed to further evaluate the effect of anti-TNF treatment and to compare its side-effects with those of corticosteroids.

Adult↗
PubMed2005

Anti-TNF-alpha therapy for sight threatening uveitis.

AIM: To describe the effect of additional treatment with anti-TNF-alpha therapy in a case series of 13 patients with serious sight threatening uveitis. METHODS: 13 patients with serious sight threatening uveitis were included, of whom six had Behçet's disease, five had idiopathic posterior uveitis, one had sarcoidosis, and one birdshot retinochoroiditis. Onset and course of ocular inflammation, inflammatory signs, and visual acuity were assessed. Patients were treated with 200 mg (approximately 3 mg/kg) infliximab infusion. Repeat infusions were given based on clinical response. RESULTS: Infliximab treatment resulted in an effective suppression of ocular inflammation in all patients. In patients with non-Behcet's disease uveitis visual acuity in six out of eight improved or was stable. In patients with Behcet's disease visual acuity in five out of six improved or was stable. CONCLUSION: Anti-TNF-alpha treatment may be of value in the treatment of uveitis, and in patients with Behçet's disease, leading to suppression of ocular inflammation, vasculitis, and improvement of vision in the majority. Based on these results a controlled masked study is warranted.

Adult↗
PubMed2005

Somatostatin-related therapeutics in ophthalmology: a review.

Somatostatin and its derivatives have been predominantly studied and succesfully used in endocrinological diseases. This article reviews the rationale of the use of somatostatin and its derivatives in ophthalmology based on current understanding of its action in the eye and summarizes previously published controlled studies and case series. The article points out future possible applications. Larger randomised controlled studies are necessary to confirm its current and future use. New ways of application could facilitate its broader use in ophthalmology.

Angiogenesis Inhibitors↗
PubMed2004

Somatostatin receptor distribution and function in immune system.

Somatostatin and cortistatin, a recently discovered endogenous neuropeptide relative of somatostatin, have multiple modulatory effects on the immune system. The specific somatostatin receptor distribution might in part explain the heterogeneity of effects of somatostatin or its analogs on immunocytes. In fact, somatostatin receptor subtypes are differentially expressed on specific cell subsets within the organs of the immune system and the expression is dynamically regulated and seems to depend on the traffic of these cells through and within lymphoid structure and homing in tissues. Somatostatin effects on immune cells are mainly based on autocrine and paracrine modes of action. In fact, activated cells producing somatostatin (or cortistatin) may interact with other cells expressing the receptors. Here, we review the postulated modes of action of somatostatin and somatostatin-like peptides, including the currently available synthetic somatostatin analogs, in cells of the immune system. We also discuss the wide distribution of somatostatin and its specific five receptor subtypes in immune cell lines, as well as throughout animal and human lymphoid organs, in both normal and pathological conditions.

Animals↗
PubMed2004

Experience with cyclosporine in endogenous uveitis posterior.

Treatment with cyclosporine (CsA) has considerably improved the visual prognosis of patients suffering from endogenous posterior uveitis (EPU). However, the therapeutic benefits of CsA are partially outweighed by its many side effects, most notably nephrotoxicity and hypertension. Low-dose CsA regimens have reduced toxicity but have not been able to completely eliminate this problem. New therapeutic approaches, such as anti-tumor necrosis factor alpha treatment or immunosuppression with drugs including tacrolimus, sirolimus, and interleukin-2 receptor antibodies, are currently under evaluation. Hopefully such strategies will further reduce the morbidity of EPU and minimize the adverse effects associated with conventional therapies.

Cyclosporine↗
PubMed2004

Autologous peripheral retinal pigment epithelium translocation in patients with subfoveal neovascular membranes.

AIM: To evaluate the possibility of translocating autologous peripheral retinal pigment epithelial (RPE) cells and enhance their adhesion to improve functional outcome after choroidal neovascular membrane extraction in patients with subfoveal neovascular membranes. METHODS: A prospective, non-controlled surgical study in eight consecutive patients operated between February and July 2001 with final data monitoring in July 2002. All patients had mixed subfoveal membranes of 2-4 disc diameters. Functional tests included Snellen vision and central fixation testing. During vitrectomy, after the extraction of the neovascular complex, 8 x 10(4)-16 x 10(4) RPE cells were removed from the periphery and translocated under the macula following the submacular injection of 2 microg of poly-L-lysine to promote adhesion of the cells. RESULTS: With a follow up ranging from 3 months to 16 months, a pigmented area was seen in the extraction bed of the neovascular membrane in only one patient. Fixation was at the edge of the extraction bed in three patients. Vision remained the same in five patients and deteriorated in three (all with retinal detachment). Retinal detachment due to proliferative vitreoretinopathy occurred in three patients. CONCLUSIONS: The translocation of autologous peripheral RPE cells after membrane extraction was technically possible in a sterile manner, but was associated with a high proliferative vitreoretinopathy rate and in the present series had no measurable positive effect on functional outcome.

Adult↗
PubMed2004

Somatostatin in diabetic retinopathy.

Diabetic retinopathy is a leading cause of legal blindness in the adult population (30-70 year olds). The anatomical changes that occur in the retina during the course of disease are well defined in the literature but the causes are not yet fully understood. Laser photocoagulation of the retina and vitrectomy are currently used to treat diabetic retinopathy but the procedures are invasive and provide only temporary protection. The use of long-acting analogues of the naturally occurring peptide, somatostatin, has been considered by some a promising therapeutic option for retinopathy over the last decade. Experimental evidence supports its use in diabetic retinopathy but further clinical evidence, from larger treatment groups of longer trial duration, is required. Improved analogues with increased selectivity and modified bi-specific analogues are currently emerging and may help to make the use of somatostatin analogues a more realistic option in the treatment of diabetic retinopathy.

Animals↗
PubMed2003

[Twenty-five years of cyclosporin use in transplantation medicine].

Cyclosporin has greatly improved the short and medium-term outcomes for solid organ transplantation. However, the effect on the long-term outcome has been less impressive. This can partly be attributed to the side effects of cyclosporin, and partly to the fact that the use of cyclosporin has not led to a reduced incidence of chronic allograft nephropathy. Efforts to minimise these side effects have led to the development of the microemulsion form of cyclosporin and improved methods for therapeutic drug monitoring (dosage based on blood levels instead of body weight). Finally, the introduction of new immunosuppressive drugs has made it possible to further reduce the dose of cyclosporin; this might eventually lead to cyclosporin-free immunosuppressive regimens.

Cyclosporine↗
PubMed2003

The role of octreotide scintigraphy in rheumatoid arthritis and sarcoidosis.

Somatostatin receptors are widely expressed on cells and tissues throughout the human body. Apart from their expression in the physiological target organs of the peptide, somatostatin receptors are also expressed in various tumours. The expression of somatostatin receptors on neuroendocrine tumours led to the development of somatostatin receptor scintigraphy using [(111)In-DTPA-D-Phe(1)]-octreotide ((111)In-pentetreotide) in order to visualize somatostatin receptor positive tumours and their metastases in vivo. Previous studies reported the expression of somatostatin receptors in both normal and pathological cells and tissues of the human immune system as well. Somatostatin receptors have been demonstrated in Hodgkin's and non-Hodgkin's lymphomas and sst scintigraphy has shown to be a useful tool in diagnosis and staging of these diseases. Moreover, sst expression has also been detected in granulomateus diseases, like sarcoidosis and auto-immune diseases, like rheumatoid arthritis. In this paper we discuss the (possible) role of somatostatin receptor scintigraphy in diagnosis, staging or follow-up of patients suffering from sarcoidosis and rheumatoid arthritis.

Arthritis, Rheumatoid↗
PubMed2001

Neuroendocrine aspects of immunolymphoproliferative diseases.

Exchange of information occurs between cells of neuroendocrine and immune systems. Neuroendocrine hormones may modulate lymphoid cell activities, including proliferation and mitogenesis, and immune cells may produce neuropeptides as well. Neuropetide Y is synthesized in B-cell leukaemia lymphoblasts, while substance P immunoreactivity has been detected in neoplastic haematological samples of different types of leukaemias. The presence of receptors for neuropeptides on different animal and human lymphoid cell lines, as well as in several types of animal and human lymphoproliferative diseases has been demonstrated. Species variability in receptor distribution has been shown as well. Receptor expression in immune cells may be regulated by changes in microenvironmental conditions, it may also be related to the activation and/ or proliferation state of cells. Vasoactive intestinal peptides receptors have been detected in myeloma cells, while somatostatin receptors have been first detected in vitro on resting lymphocytes and cells of the monocyte/macrophage lineage, and later on human activated lymphocytes and on lymphoblastic leukaemia cells. Somatostatin receptors have been found in biopsies from patients with malignant lymphomas. Tumor localization in non-Hodgkin lymphomas and Hodgkin's disease can be visualized by in vivo somatostatin receptor scintigraphy, contributing to establish the diagnosis and the stage of the disease. Recently. somatostatin receptors have been in vivo and in vitro detected in human thymic tumors. Although treatment of lymphoproliferative diseases with somatostatin analogs is a little explored field, partial remission was found in patients with low-grade non-Hodgkin lymphoma and cutaneous T-cell lymphoma, and a successful treatment with octreotide has been reported in patients with thymoma. Specific somatostatin receptors present in progenitors of immune cells are not expressed in the mature phenotype, while they can be detected in transformed cell lines. The possibility that this phenomenon is caused by oncogene expression cannot be ruled out. Moreover, preliminary data showed a developmental expression of somatostatin receptors in lymphoid cells, suggesting a potential role for neuropeptide receptors as differentiation markers. Although controlled studies are warranted to investigate the efficacy of the currently available analogs, somatostatinergic compounds may be of interest in the treatment of lymphoproliferative malignancies. A promising approach in refractory patients with somatostatin receptor positive malignant lymphomas may be radionuclide-targeted and cytotoxic analog therapy. These concepts increase the possibility of a wider antitumor treatment with ligands for neuroepeptide receptors than in established 'classic' neuroendocrine tumors.

Cell Differentiation↗