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Biomedical subjects

J D Bos

Publications and source records attributed to J D Bos.

At least 19 recordsLinked to original sources
PubMed2005

Leukocyte extravasation as a target for anti-inflammatory therapy - Which molecule to choose?

In view of the central pathogenic importance of leukocyte extravasation in inflammatory skin diseases, therapeutic interference with this - surprisingly complex - process is clearly a promising new approach for treating these dermatoses. Despite some disappointments during the clinical use of these agents and despite their crippling price tag, the recent incorporation of biologicals that target defined molecular controls of leukocyte extravasation into dermatological and rheumatological practise, consequently, has greatly enriched our therapeutic options for battling major, chronic, inflammatory dermatoses such as psoriasis. However, the - as yet unresolved and still rather controversially discussed - critical question is: Which of the multiple steps that control leukocyte extravasation in the human system really offer the most promising, most pragmatic, and safest molecular targets for therapeutic intervention for which disease entity? The current debate intends to stimulate public and rational debate of this crucial issue, beyond the evident commercial interests that are touched by whatever stand one takes.

Anti-Inflammatory Agents↗
PubMed2005

A multicentre, randomized, double-blind, controlled study of long-term treatment with 0.1% tacrolimus ointment in adults with moderate to severe atopic dermatitis.

BACKGROUND: Atopic dermatis (AD) is a chronic disease that often requires long-term treatment. Topical corticosteroids are the usual therapy for patients with AD, but prolonged usage can result in skin atrophy and other side-effects. OBJECTIVES: In a randomized, double-blind, comparative study, to compare the efficacy and safety of a 6-month treatment period with 0.1% tacrolimus ointment vs. a corticosteroid ointment regimen in adults with moderate to severe AD. METHODS: Treatment was applied twice daily for a maximum of 6 months. Patients in the tacrolimus treatment group (n = 487) applied 0.1% tacrolimus ointment to all affected areas over the whole body. The patients treated with the corticosteroid regimen (n = 485) applied 0.1% hydrocortisone butyrate ointment to affected areas on the trunk and extremities and 1% hydrocortisone acetate ointment to affected areas on the face and neck. The study primary endpoint was the response rate, i.e. the proportion of patients with at least 60% improvement in the modified Eczema Area and Severity Index (mEASI) between baseline and month 3. RESULTS: By month 3, more patients in the 0.1% tacrolimus group responded to treatment (72.6% vs. 52.3% in the corticosteroid group, P < 0.001). The patients treated with 0.1% tacrolimus also showed greater improvement in mEASI, EASI, affected body surface area and physician and patient assessments of global response. Patients applying 0.1% tacrolimus ointment experienced more skin burning (52.4% vs. 13.8% in the corticosteroid group; P < 0.001). In most patients, skin burning was mild to moderate in severity and decreased rapidly after the first week of treatment. There was no increase in the incidence of infections or malignancies over time in either treatment group. CONCLUSIONS: Long-term treatment with 0.1% tacrolimus ointment is significantly more efficacious than a corticosteroid ointment regimen in adults with moderate to severe AD.

Adult↗
PubMed2005

Psoriasis: dysregulation of innate immunity.

The current understanding of the function of natural killer (NK) T cells in innate immunity and their potential to control acquired specific immunity, as well as the remarkable efficacy of antitumour necrosis factor-alpha biological treatments in psoriasis, forces us to refine the current T-cell hypothesis of psoriasis pathogenesis, and to give credit to the role of innate immunity. Psoriasis might be envisioned to be a genetically determined triggered state of otherwise dormant innate immunity. This aggravated state of innate immunity is represented by the activity of NK T cells, dendritic cells, neutrophils and keratinocytes, leading to the recruitment and activation of preferentially type 1 T cells, possibly in an antigen-independent way. Keratinocytes in psoriasis then are sensitive to the effects of T-cell activation and cytokine production, interferon (IFN)-gamma, by responding with psoriasiform hyperplasia. The chronic inflammation of psoriatic lesions suggests that this might be due to a deficiency in downregulation processes (e.g. a defect in the regulatory T-cell repertoire) and/or the persistence of an unknown trigger resulting in an exaggerated innate immune response.

Antigens↗
PubMed2005

Quality of care in patients with psoriasis: an initial clinical study of an international disease management programme.

BACKGROUND: Patients with psoriasis have to cope with their disease for many years or even throughout their entire life. To provide optimal care, a disease management programme was developed. This programme consisted of disease education, disease management training, and psychological support, together with topical treatment. OBJECTIVE: To test a disease management programme in dermatological practice, to assess patients' satisfaction with this programme, and adherence to topical treatment. Additionally, disease severity and quality of life were assessed. METHODS: An initial clinical investigation was conducted in 10 European treatment centres. A total of 330 patients were included. Patient satisfaction, adherence, disease severity and quality of life were measured with study-specific and standardized self-report questionnaires. RESULTS: Patients reported a high degree of satisfaction with the programme, and a high degree of adherence to topical treatment. Disease severity and quality of life significantly improved. The programme was well received by the participating professionals. CONCLUSIONS: The disease management programme was found to be a useful tool in the management of psoriasis, providing patients with relief from the burden of psoriasis in everyday life. A full-scale evaluation is recommended.

Dermatologic Agents↗
PubMed2004

0.03% Tacrolimus ointment applied once or twice daily is more efficacious than 1% hydrocortisone acetate in children with moderate to severe atopic dermatitis: results of a randomized double-blind controlled trial.

BACKGROUND: Topical corticosteroids are the usual treatment for atopic dermatitis (AD) in children but can have side-effects. OBJECTIVES: This study compared the efficacy and safety of 0.03% tacrolimus ointment applied once or twice daily over a 3-week period with the twice daily application of 1% hydrocortisone acetate (HA) ointment in children with moderate to severe AD. PATIENTS AND METHODS: Patients applied ointment daily to all affected body surface areas. The primary study endpoint was the percentage change in the modified Eczema Area and Severity Index (mEASI) between baseline and treatment end. RESULTS: Six hundred and twenty-four patients, aged 2-15 years, applied 0.03% tacrolimus ointment once daily (n = 207), twice daily (n = 210) or 1% HA twice daily (n = 207). By the end of treatment, application of 0.03% tacrolimus ointment both once or twice daily resulted in significantly greater median percentage decreases in mEASI (66.7% and 76.7%, respectively) compared with 1% HA (47.6%; P < 0.001). Furthermore, the median percentage decrease in mEASI was significantly greater for patients applying 0.03% tacrolimus twice daily compared with once daily (P = 0.007). Patients with severe AD benefited especially from twice daily application of 0.03% tacrolimus ointment compared with once daily application (P = 0.001). Transient mild to moderate skin burning occurred significantly more often in the 0.03% tacrolimus groups (P = 0.028) but resolved in most cases within 3-4 days. Laboratory parameters showed no clinically relevant changes. CONCLUSIONS: 0.03% tacrolimus ointment applied once or twice daily is significantly more efficacious than 1% HA in treating moderate-severe AD in children. Twice daily application of 0.03% tacrolimus ointment results in the greatest improvement in mEASI, and is especially effective in patients with severe baseline disease.

Administration, Topical↗
PubMed2004

Long-term safety and tolerability of pimecrolimus cream 1% and topical corticosteroids in adults with moderate to severe atopic dermatitis.

OBJECTIVE: This randomized, double-blind, multi-centre study compared the long-term safety and tolerability of pimecrolimus cream 1% and topical corticosteroids (TCS) in 658 adults with moderate-severe atopic dermatitis (AD). METHODS: Patients applied either pimecrolimus or TCS (i.e. 0.1% triamcinolone acetonide cream and/or 1% hydrocortisone acetate cream) twice daily to all affected areas until complete clearance or for up to 1 year. The study was approved by the institutional review board or ethics committee at each centre. RESULTS: A majority of patients treated with either pimecrolimus or TCS used the drug on a continuous basis over 1 year. In patients who had >30% of the body surface involved by AD, the incidence rate of all skin infections was significantly lower in the pimecrolimus group than in the TCS group (95% CI of the treatment difference: -25.3% to -3.4%). The most frequent application site reaction was burning (25.9% of patients on pimecrolimus and 10.9% on TCS), which was transient and mild-moderate in most cases. Three TCS-treated patients reported skin striae. There were no treatment-related serious or clinically significant systemic adverse events. Efficacy was better in patients on continuous TCS therapy, although patients completing the study were similarly well-controlled in both groups. About 42% of the pimecrolimus-treated patients were maintained for 1 year without TCS. CONCLUSION: Pimecrolimus demonstrated a favourable safety profile when used to treat adult patients with moderate-severe AD for up to 1 year. A significant proportion of patients could be maintained without TCS for a year.

Administration, Cutaneous↗
PubMed2004

Clinical improvement in chronic plaque-type psoriasis lesions after narrow-band UVB therapy is accompanied by a decrease in the expression of IFN-gamma inducers -- IL-12, IL-18 and IL-23.

Type-1 cytokine-producing T cells are important in the pathogenesis of psoriasis vulgaris, for which efficient therapy is provided by means of narrow-band ultraviolet-B (NB-UVB). The expression of the type-1 cytokine interferon-gamma (IFN-gamma) is regulated by interleukin-12 (IL-12), IL-15, IL-18 and IL-23; however, not much is known about the effect of this therapy on the levels of these cytokines in lesional psoriatic skin in situ. In this study, we investigated the effects of NB-UVB therapy on the expression of IFN-gamma-inducing cytokines. Ten patients with chronic plaque-type psoriasis selected to be treated with NB-UVB therapy were recruited for these experiments and the expression of cytokines IL-12, IL-15, IL-18, IL-23 and IFN-gamma in lesional psoriatic skin before, during and after therapy was determined with the help of immunohistochemistry. Double staining was performed in order to determine the cell types expressing these cytokines. The decrease in the psoriasis area and severity index was accompanied by a significant decrease in the expression of IFN-gamma, and concomitantly, significant reduction of IFN-gamma inducers -- IL-12, IL-18 and IL-23. Thus, we concluded that the decrease of IFN-gamma expression in psoriasis lesions after NB-UVB therapy could be a result of diminished expression of IL-12, IL-18 and IL-23 in lesional skin. Therapies targeting these three cytokines should, therefore, be considered in the treatment of psoriasis.

Adult↗
PubMed2004

Biological therapies in the systemic management of psoriasis: International Consensus Conference.

Psoriasis is a chronic, immune-mediated disorder that usually requires long-term treatment for control. Approximately 25% of patients have moderate to severe disease and require phototherapy, systemic therapy or both. Despite the availability of numerous therapeutic options, the long-term management of psoriasis can be complicated by treatment-related limitations. With advances in molecular research and technology, several biological therapies are in various stages of development and approval for psoriasis. Biological therapies are designed to modulate key steps in the pathogenesis of psoriasis. Collectively, biologicals have been evaluated in thousands of patients with psoriasis and have demonstrated significant benefit with favourable safety and tolerability profiles. The limitations of current psoriasis therapies, the value of biological therapies for psoriasis, and guidance regarding the incorporation of biological therapies into clinical practice are discussed.

Age Factors↗
PubMed2004

The role of topical calcineurin inhibitors in atopic dermatitis.

For more than five decades, topical corticosteroids and emollients have been the mainstay of therapy for atopic dermatitis. However, the potential for side-effects limits the clinical utility of corticosteroids in providing long-term disease control. With a unique mode of action that differs from that of corticosteroids, the steroid-free topical calcineurin inhibitors (TCIs), tacrolimus ointment and pimecrolimus cream, provide skin-selective treatment that targets key factors involved in the pathogenesis of this chronic disease. An extensive series of clinical trials involving more than 16,000 patients with predominantly moderate to severe atopic dermatitis in tacrolimus studies and over 2000 patients with primarily mild to moderate disease in pimecrolimus studies has shown that both TCIs provide effective and well-tolerated treatment for atopic dermatitis. Randomized controlled trials have demonstrated that tacrolimus is superior to conventional hydrocortisone-based regimens and does not cause skin atrophy or other steroidal side-effects. Both tacrolimus and pimecrolimus prevent disease flares and provide progressive and sustained disease improvement with long-term therapy. These and other clinical benefits of TCIs are discussed, together with the safety profiles of tacrolimus and pimecrolimus and their use in clinical practice. In addition, this review summarizes findings from the many trials carried out with these agents and outlines how TCIs can provide long-term treatment and control of a chronic skin disease that may persist for years.

Administration, Topical↗
PubMed2004

Early effects of tumour necrosis factor alpha blockade on skin and synovial tissue in patients with active psoriasis and psoriatic arthritis.

BACKGROUND: Tumour necrosis factor alpha (TNFalpha) blockade using infliximab, a chimeric anti-TNFalpha antibody, is an effective treatment for both psoriasis and psoriatic arthritis (PsA). OBJECTIVE: To analyse the early effects of infliximab treatment on serial skin and synovial tissue biopsy samples. METHODS: Twelve patients with both active psoriasis and PsA received a single infusion of either infliximab (3 mg/kg) (n = 6) or placebo (n = 6) intravenously. Synovial tissue and lesional skin biopsy specimens were obtained at baseline and 48 hours after treatment. Immunohistochemical analysis was performed to analyse the inflammatory infiltrate. In situ detection of apoptotic cells was performed by TUNEL assay and by immunohistochemical staining with anti-caspase-3 antibodies. Stained tissue sections were evaluated by digital image analysis. RESULTS: A significant reduction in mean (SEM) T cell numbers was found in both lesional epidermis (baseline 37 (11) cells/mm, 48 hours 26 (11), p = 0.028) and synovial tissue (67 (56) cells/mm(2)v 32 (30), p = 0.043) after infliximab treatment, but not after placebo treatment (epidermis 18 (8) v 43 (20), NS; synovium 110 (62) v 46 (21), NS). Similarly, the number of macrophages in the synovial sublining was significantly reduced after anti-TNFalpha treatment (100 (73) v 10 (8), p = 0.043). The changes in cell numbers could not be explained by induction of apoptosis at the site of inflammation. CONCLUSIONS: The effects of anti-TNFalpha therapy in psoriasis and psoriatic arthritis may be explained by decreased cell infiltration in lesional skin and inflamed synovial tissue early after initiation of treatment.

Adult↗
PubMed2003

[European standard regarding clothing and protection against ultraviolet radiation].

Overexposure to ultraviolet radiation (UVR) causes skin damage. An increasing awareness of this must result in people consciously wanting to protect themselves from UVR by means of clothing. The first part of the European standard on UVR-protective clothing--about test methods--is now available. In the second part the classification and labelling of UVR-protective clothing are detailed. The degree of protection the clothing provides against UVR is expressed as the ultraviolet-protection factor (UPF). The UPF is inversely proportional to the quantity of UVR which the clothing allows through. UVR-protective clothing which satisfies the European standard will bear the European UPF label '40+'. To obtain this label the entire clothing must have a UPF of at least 40. The wording: 'Sun exposure causes skin damage', 'Only covered areas are protected' and 'The protection offered by this item may be reduced with use or if the material is stretched or wet' must be added to the label.

Clothing↗
PubMed2003

Causes, investigation and treatment of leg ulceration.

Chronic ulceration of the lower leg is a frequent condition, with a prevalence of 3-5% in the population over 65 years of age. The incidence of ulceration is rising as a result of the ageing population and increased risk factors for atherosclerotic occlusion such as smoking, obesity and diabetes. Ulcers can be defined as wounds with a 'full thickness depth' and a 'slow healing tendency'. In general, the slow healing tendency is not simply explained by depth and size, but caused by an underlying pathogenetic factor that needs to be removed to induce healing. The main causes are venous valve insufficiency, lower extremity arterial disease and diabetes. Less frequent conditions are infection, vasculitis, skin malignancies and ulcerating skin diseases such as pyoderma gangrenosum. But even rarer conditions exist, such as the recently discovered combination of vasculitis and hypercoagulability. For a proper treatment of patients with leg ulcers, it is important to be aware of the large differential diagnosis of leg ulceration.

Arterial Occlusive Diseases↗
PubMed2003

Evaluation of medium-dose UVA1 phototherapy in localized scleroderma with the cutometer and fast Fourier transform method.

PURPOSE: To evaluate the efficacy of medium-dose UVA1 phototherapy in patients with localized scleroderma. METHOD: A controlled pilot study with medium-dose UVA1 (48 J/cm2) was performed. The results were evaluated by means of a skin score and two objective methods for quantifying sclerosis (cutometer and fast Fourier transform method). Patients were treated 4 times a week for 5 weeks. The follow-up period was 12 weeks. RESULTS: All patients responded to therapy. Skin score and cutometer results showed improvement of skin elasticity of treated skin compared to control skin. Fast Fourier transform measurements showed no change in bundle orientation ratio and spacing. CONCLUSION: We concluded that treatment for 12 weeks 4 times a week with medium-dose UVA1 may be a beneficial therapy and a well-tolerated treatment modality for localized scleroderma (morphea). After 12 weeks, improvement of skin sclerosis can be detected by skin score and cutometer measurements but not by the fast Fourier transform method.

Adolescent↗
PubMed2003

Potential effect of patient-assisted teledermatology on outpatient referral rates.

We carried out a pilot study on the feasibility and accuracy of store-and-forward teledermatology based on patient-provided images and history as a triage tool for outpatient consultation. Patients referred by their general practitioner provided a history and images via the Internet. The information was reviewed by one of 12 teledermatologists and the patient then visited a different dermatologist in person within two days. Three independent dermatologists compared the remote and in-person diagnoses in random order to determine diagnostic agreement. Broader agreement was also measured, by comparing the main disease groups into which the two diagnoses fell. The teledermatologists indicated whether an in-person consultation or further investigations were necessary. There were 105 eligible patients, aged four months to 72 years, who were willing to participate. For the 96 cases included in the analysis, complete diagnostic agreement was found in 41% (n=39), partial diagnostic agreement in 10% (n=10) and no agreement in 49% (n=47). There was disease group agreement in 66% of cases (n=63). Nearly a quarter (23%) of participating patients could have safely been managed without an in-person visit to a dermatologist.

Adolescent↗
PubMed2002

Cyclosporin trough levels: is monitoring necessary during short-term treatment in psoriasis? A systematic review and clinical data on trough levels.

BACKGROUND: Cyclosporin is an effective treatment for severe plaque psoriasis. Unfortunately, its use may be limited by time- and dose-related nephrotoxicity. Serum trough levels may be useful for monitoring the risk of nephrotoxicity. OBJECTIVES: To determine whether monitoring of trough levels is necessary in psoriasis patients undergoing short-term treatment with cyclosporin. METHODS: A computerized and manual literature search identified studies on adults with plaque-type psoriasis treated with cyclosporin < or = 5 mg kg-1 daily, in which trough levels were measured in whole blood. Number of patients, treatment duration, formulation and dosage, renal function tests and trough levels were extracted. The association between renal function and trough levels was investigated. Additionally, in a randomized controlled trial on cyclosporin vs. methotrexate in moderate to severe psoriasis, cyclosporin trough levels were measured frequently in 20 patients during 12 weeks of treatment. The Pearson correlation coefficient between serum creatinine and cyclosporin trough levels was calculated. RESULTS: Fifty-six articles were found concerning cyclosporin trough level measurements in psoriasis patients, of which eight were analysed. Many studies were excluded due to inappropriate cyclosporin dosages used. As data were heterogeneous and lacked various key parameters, a correlation study and a meta-analysis could not be performed. Instead, a quantitative description of the literature was given. No high mean trough levels or elevations of serum creatinine were described. In our clinical study, all the mean trough levels in 17 patients treated with cyclosporin 3 mg kg-1 daily were within the therapeutic range (< 200 ng mL-1). Elevated trough levels were found in two of three patients treated with cyclosporin 3-5 mg kg-1 daily. No signs of renal dysfunction were seen. CONCLUSIONS: The literature does not provide a definitive answer on whether monitoring cyclosporin trough levels in patients with psoriasis should be standard practice. Our own data show no need for cyclosporin trough level monitoring during short-term treatment with cyclosporin 3 mg kg-1 daily. However, when cyclosporin doses are > 3 mg kg-1 daily, monitoring may be indicated.

Adult↗
PubMed2002

Atopiform dermatitis.

It is proposed to introduce the term 'atopiform dermatitis' to describe patients who have dermatitis with many of the characteristics of true atopic dermatitis, but who are not atopic. Atopy should be defined as the genetically determined and environmentally influenced syndrome in which the primary immunological abnormality is the production of allergen-specific IgE. It is suggested that by making a distinction between atopiform dermatitis and true atopic dermatitis, subsequent genetic, immunological and therapeutic studies will be improved. Furthermore, atopiform dermatitis would be a more appropriate diagnosis for the atopic dermatitis-like skin diseases that may occur in syndromes such as phenylketonuria, Schwachman's syndrome, Wiskott-Aldrich syndrome, Netherton's syndrome, Job's syndrome, selective IgA deficiency, agammaglobulinaemia and ataxia telangiectasia. In contrast to patients with true atopy, patients with atopiform dermatitis can logically be advised that allergen avoidance is not required, as they have no allergen-specific IgE.

Dermatitis, Atopic↗
PubMed2002

Hyperproliferation of normally quiescent keratinocytes in non-lesional psoriatic skin due to high calcium concentration (an organotypic culture model).

Calcium plays an important role in the regulation of different functions of keratinocytes. In the present work we studied the effect of different extracellular calcium concentrations (0.01 mM-2.0 mM) on the proliferation and differentiation of human keratinocytes in normal human and non-lesional psoriatic skin. Using explant culture model, the proliferative and differentiated subsets of keratinocytes were detected by specific antibodies related to cell proliferation [beta-1 integrin (CD29), proliferating cell antigen (Ki67), proliferating cell nuclear antigen (PCNA)] and differentiation [differentiated cell cytokeratins (K1/K10) and differentiating cell antigen (lectin Ulex europaius agglutinin, UEA-1)]. After 4 days of culturing at high Ca2+ (2.0 mM) we observed marked hyperproliferation among the normally quiescent keratinocytes of non-lesional psoriatic skin. In normal uncultured and cultured skin and in uncultured and two-day-cultured non-lesional psoriatic skin both at normal (1.2 mM) and at high (2.0 mM) Ca2+ concentration only one layer of basal CD29+/Ki67+/K1/K10-/UEA-1- cell was observed. In sections from non-lesional psoriatic skin cultured for 4 days in the presence of high Ca2+ (2.0 mM) this cell population has expanded from at least three layers above the basement membrane. This expanded cell population of the 4-day high Ca2+ cultured non-lesional skin showed clear PCNA positive staining on frozen sections with the strongest positivity among the most basal localized cells. These data suggest that (i) extracellular Ca2+ concentration can influence the proliferation of basal ("stem") keratinocytes, (ii) the proliferative response to high Ca2+ concentration of psoriatic non-lesional basal keratinocytes differs from that of normal basal keratinocytes, (iv) changes in the extracellular Ca2+ milieu might play a role in the induction of the hyperproliferative psoriatic lesion.

Calcium↗