Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Robert Gniadecki is active.

Publication


Featured researches published by Robert Gniadecki.


British Journal of Dermatology | 2011

Comparison of drug survival rates for adalimumab, etanercept and infliximab in patients with psoriasis vulgaris

Robert Gniadecki; Knud Kragballe; Tomas Norman Dam; L. Skov

Background  Adherence to treatment is an indicator of treatment success. Long‐term data on adherence to biologic treatment in psoriasis are lacking.


Annals of Internal Medicine | 2012

Adalimumab for the Treatment of Moderate to Severe Hidradenitis Suppurativa: A Parallel Randomized Trial

Alexa B. Kimball; Francisco A. Kerdel; David Adams; Ulrich Mrowietz; Joel M. Gelfand; Robert Gniadecki; Errol P. Prens; Joel Schlessinger; Christos C. Zouboulis; Hessel H. van der Zee; Marie R. Rosenfeld; Parvez Mulani; Yihua Gu; Susan K. Paulson; Martin M. Okun; Gregor B. E. Jemec

BACKGROUND Hidradenitis suppurativa (HS) is a chronic, painful skin disease characterized by abscesses, nodules, and draining fistulas in the axilla and groin of young adults. OBJECTIVE To evaluate the efficacy and safety of adalimumab, an anti-tumor necrosis factor-α antibody, in patients with moderate to severe HS. DESIGN Phase 2, parallel, randomized, placebo-controlled trial consisting of a blinded 16-week period (period 1) and an open-label 36-week period (period 2). All study personnel, investigators, and patients remained blinded to treatment group throughout the study. (ClinicalTrials.gov: NCT00918255) SETTING 26 academic and private practice medical centers in the United States and Europe. PATIENTS 154 adult patients with moderate to severe HS who were unresponsive or intolerant to oral antibiotics. INTERVENTION Patients were assigned in a 1:1:1 ratio to adalimumab, 40 mg/wk; adalimumab, 40 mg every other week (EOW); or placebo. All patients received adalimumab, 40 mg EOW, at the beginning of period 2 but switched to weekly dosing if the response was suboptimal (HS Physicians Global Assessment [PGA] score of moderate or worse) at weeks 28 or 31. MEASUREMENTS The primary outcome measure (clinical response) was the proportion of patients achieving an HS-PGA score of clear, minimal, or mild with at least a 2-grade improvement relative to baseline at week 16. RESULTS At week 16, 3.9% of placebo patients (2 of 51), 9.6% of EOW patients (5 of 52), and 17.6% of weekly patients (9 of 51) achieved clinical response (EOW vs. placebo strata-adjusted difference, 5.6% [95% CI, -4.0% to 15.3%]; P = 0.25; weekly vs. placebo strata-adjusted difference, 13.7% [CI, 1.7% to 25.7%]; P = 0.025). Serious adverse event rates were 3.9%, 5.8%, and 7.8% for placebo, EOW, and weekly patients, respectively (EOW vs. placebo difference, 1.8% [CI, -6.4% to 10.1%]; weekly vs. placebo difference, 3.9% [CI, -5.2% to 13.0%]). Significantly greater improvements in patient-reported outcomes and pain were seen in the weekly dosing group than in the placebo group. A decrease in response was seen after the switch from weekly to EOW dosing in period 2. LIMITATIONS Weeks 16 to 52 of the study were open-label. The study was not powered to assess the risk for known serious adverse effects of adalimumab, such as tuberculosis, other serious infections, and demyelinating disorders. CONCLUSION Adalimumab dosed once per week alleviates moderate to severe HS. PRIMARY FUNDING SOURCE Abbott Laboratories.


Blood | 2011

Diagnostic microRNA profiling in cutaneous T-cell lymphoma (CTCL)

Ulrik Ralfkiaer; Peter Hagedorn; Nannie Bangsgaard; Marianne B. Løvendorf; Charlotte B. Ahler; Lars Svensson; Katharina L. Kopp; Marie T. Vennegaard; Britt Lauenborg; John R. Zibert; Thorbjørn Krejsgaard; Charlotte M. Bonefeld; Rolf Søkilde; Lise Mette Gjerdrum; Tord Labuda; Anne-Merete Mathiesen; Kirsten Grønbæk; Mariusz A. Wasik; Malgorzata Sokolowska-Wojdylo; Catherine Queille-Roussel; Robert Gniadecki; Elisabeth Ralfkiaer; Carsten Geisler; Thomas Litman; Anders Woetmann; Christian Glue; Mads A. Røpke; Lone Skov; Niels Ødum

Cutaneous T-cell lymphomas (CTCLs) are the most frequent primary skin lymphomas. Nevertheless, diagnosis of early disease has proven difficult because of a clinical and histologic resemblance to benign inflammatory skin diseases. To address whether microRNA (miRNA) profiling can discriminate CTCL from benign inflammation, we studied miRNA expression levels in 198 patients with CTCL, peripheral T-cell lymphoma (PTL), and benign skin diseases (psoriasis and dermatitis). Using microarrays, we show that the most induced (miR-326, miR-663b, and miR-711) and repressed (miR-203 and miR-205) miRNAs distinguish CTCL from benign skin diseases with > 90% accuracy in a training set of 90 samples and a test set of 58 blinded samples. These miRNAs also distinguish malignant and benign lesions in an independent set of 50 patients with PTL and skin inflammation and in experimental human xenograft mouse models of psoriasis and CTCL. Quantitative (q)RT-PCR analysis of 103 patients with CTCL and benign skin disorders validates differential expression of 4 of the 5 miRNAs and confirms previous reports on miR-155 in CTCL. A qRT-PCR-based classifier consisting of miR-155, miR-203, and miR-205 distinguishes CTCL from benign disorders with high specificity and sensitivity, and with a classification accuracy of 95%, indicating that miRNAs have a high diagnostic potential in CTCL.


British Journal of Dermatology | 2015

Comparison of long-term drug survival and safety of biologic agents in patients with psoriasis vulgaris

Robert Gniadecki; B Bang; L.E. Bryld; L Iversen; Stine Lasthein; Lone Skov

Drug survival (time to drug discontinuation) has recently emerged as an important parameter reflecting the long‐term therapeutic performance in a real‐life setting. Biologic drug survival in psoriasis is mainly limited by a gradual loss of efficacy over time. Previous studies have been limited by small patient population size and short observation times and yielded discrepant survival times for different biologics.


Journal of Photochemistry and Photobiology B-biology | 2000

Hydrogen peroxide is responsible for UVA-induced DNA damage measured by alkaline comet assay in HaCaT keratinocytes

Anita B. Petersen; Robert Gniadecki; Jana Vicanova; Tine Thorn; Hans Christian Wulf

We investigated the role of different reactive oxygen species (ROS) in ultraviolet A (UVA)-induced DNA damage in a human keratinocyte cell line, HaCaT. UVA irradiation increased the intracellular levels of hydrogen peroxide (H2O2), detected by a fluorescent probe carboxydichlorodihydrofluorescein, and caused oxidative DNA damage, single strand-breaks and alkali-labile sites, measured by alkaline single cell gel electrophoresis (comet assay). Superoxide anion (O2*-) was a likely substrate for H2O2 production since diethyldithiocarbamate (DDC), a superoxide dismutase blocker, decreased the level of intracellular H2O2. Hydrogen peroxide was shown to play a central role in DNA damage. Increasing the intracellular levels of H2O2 with aminotriazole (AT) (a catalase blocker) and buthionine sulfoximine (BSO) (an inhibitor of glutathione synthesis) potentiated the UVA-induced DNA damage. Exogenous H2O2 was also able to induce DNA damage. Since H2O2 alone is not able to damage DNA directly, we investigated the significance of the H2O2-derived hydroxyl radical (*OH). Addition of FeSO4, that stimulates *OH formation from H2O2 (Fenton reaction) resulted in a twofold increase of DNA-damage. Desferrioxamine, an iron chelator that blocks the Fenton reaction, prevented UVA-induced DNA damage. We also employed a panel of less specific antioxidants and enzyme modulators. Sodium selenite (Na-Se) present in glutathione peroxidase and thioredoxin reductase and addition of glutathione (GSH) prevented DNA-damage. Tocopherol potently prevented UVA-and H2O2-induced DNA damage and reduced intracellular H2O2 -levels. Ascorbic acid reduced H2O2 production, but only partly prevented DNA damage. Singlet oxygen (1O2) did not seem to play an important role in the UVA-induced DNA-damage since the specific 1O2 scavenger sodium azide (NaN3) and the less specific 1O2 scavenger beta-carotene did not markedly prevent either DNA-damage or H2O2 production. In conclusion the conversion of H2O2 to *OH appears to be the most important step in UVA-induced generation of strand breaks and alkali-labile sites and the bulk H2O2 appears to originate from O2*- generated by UVA irradiation.


Journal of Cellular Biochemistry | 2001

Role of mitochondria in ultraviolet-induced oxidative stress

Robert Gniadecki; Tine Thorn; Jana Vicanova; Anita Petersen; Hans Christian Wulf

The biological effects of ultraviolet radiation (UV), such as DNA damage, mutagenesis, cellular aging, and carcinogenesis, are in part mediated by reactive oxygen species (ROS). The major intracellular ROS intermediate is hydrogen peroxide, which is synthesized from superoxide anion (•O2−) and further metabolized into the highly reactive hydroxyl radical. In this study, we examined the involvement of mitochondria in the UV‐induced H2O2 accumulation in a keratinocyte cell line HaCaT. Respiratory chain blockers (cyanide‐p‐trifluoromethoxy‐phenylhydrazone and oligomycin) and the complex II inhibitor (theonyltrifluoroacetone) prevented H2O2 accumulation after UV. Antimycin A that inhibits electron flow from mitochondrial complex III to complex IV increased the UV‐induced H2O2 synthesis. The same effect was seen after incubation with rotenone, which blocks electron flow from NADH‐reductase (complex I) to ubiquinone. UV irradiation did not affect mitochondrial transmembrane potential (ΔΨm). These data indicate that UV‐induced ROS are produced at complex III via complex II (succinate‐Q‐reductase). J. Cell. Biochem. 80:216–222, 2000.


British Journal of Dermatology | 2007

The optimal use of bexarotene in cutaneous T‐cell lymphoma

Robert Gniadecki; Chalid Assaf; Martine Bagot; Reinhard Dummer; M Duvic; Robert Knobler; A Ranki; P Schwandt; Sean Whittaker

The management goal in cutaneous T‐cell lymphomas (CTCLs) is to improve symptoms and induce remission. Early‐stage disease is generally treated with skin‐directed therapies. However, if these do not control the disease, systemic therapy becomes necessary. Bexarotene, a novel rexinoid, is an oral, noncytotoxic drug that has been approved in Europe for the treatment of refractory advanced‐stage CTCL and in the U.S.A. for refractory CTCL. We provide guidance on the use of bexarotene in the management of CTCL, based on data from phase II/III clinical trials and the authors’ clinical experience, and suggest how the potential of the drug can be maximized. The clinical trial results with bexarotene are reviewed, especially in comparison with interferon‐α, which is the other commonly used noncytotoxic systemic therapy for CTCL. A treatment algorithm for bexarotene in refractory CTCL is suggested. As bexarotene may take time to achieve a maximum response, this algorithm recommends that therapy should be continued for a sufficient period to allow for a delayed onset of action. In addition, possible combination therapies with bexarotene are discussed. We conclude that bexarotene is effective in the management of CTCL, and has the advantage of oral administration. An on‐going randomized clinical trial comparing psoralen plus ultraviolet A (PUVA) with PUVA plus bexarotene will provide valuable information about this combination regimen in early‐stage disease, but further data are needed on the relative efficacies of other combination therapies with bexarotene in CTCL.


British Journal of Dermatology | 2006

Minimizing adverse side-effects of oral bexarotene in cutaneous T-cell lymphoma: an expert opinion

Chalid Assaf; Martine Bagot; Reinhard Dummer; Madeleine Duvic; Robert Gniadecki; Robert Knobler; Annamari Ranki; P Schwandt; Sean Whittaker

Bexarotene is an oral retinoid therapy that is effective for the treatment of early and advanced‐stage cutaneous T‐cell lymphoma (CTCL) in patients who have failed on other therapies. However, bexarotene treatment is associated with unavoidable side‐effects, in particular hypertriglyceridaemia and hypothyroidism, which are manageable with adequate concomitant medications and are reversible on cessation of treatment. A pragmatic strategy for minimizing bexarotene‐associated hypertriglyceridaemia and hypothyroidism is suggested, based on data from the studies with bexarotene in CTCL and on day‐to‐day experience with this agent in the clinical setting. The strategy anticipates that these common adverse events are likely to occur and recommends the early use of preventive therapy to lower triglycerides and elevate thyroid hormone levels in the blood, followed by subsequent monitoring, dose adjustment during bexarotene treatment, and titration of the daily bexarotene dose from 150 to 300 mg m−2, which is optimal for most patients. When further information becomes available on how bexarotene interacts with lipid metabolism and thyroid function, the management approach suggested here may need to be changed.


Experimental Dermatology | 2006

Are desmoglein autoantibodies essential for the immunopathogenesis of pemphigus vulgaris, or just ‘witnesses of disease'?

Ralf Paus; Masayuki Amagai; A. R. Ahmed; Yasuo Kitajima; Jean-Claude Bystryn; Yoram Milner; Robert Gniadecki; Michael Hertl; Carlo Pincelli; M. Fridkis‐Hareli; Yumi Aoyama; Marina Frušić-Zlotkin; Eliane J. Müller; M. David; Daniel Mimouni; D. Vind‐Kezunovic; B. Michel; Mỹ G. Mahoney; Sergei A. Grando

Abstract:  Pemphigus vulgaris (PV) is fascinating to dermatologists, epithelial biologists and immunologists alike, as its pathogenesis has been clarified to a much greater extent than that of most other organ‐specific autoimmune diseases, and as it has provided abundant novel insights into desmoglein biology and pathology along the way. Historically, the most influential PV pathogenesis concept is that of Stanley and Amagai. This concept holds that autoantibodies against desmogleins are both essential and sufficient for epidermal blister formation (acantholysis) by impeding the normal functioning of these major adhesion proteins. However, as with most good theories, this landmark concept has left a number of intriguing and important questions open (or at least has not managed to answer these to everyones satisfaction). Moreover, selected dissenting voices in the literature have increasingly called attention to what may or may not be construed as inconsistencies in this dominant PV pathogenesis paradigm of the recent past. The present debate feature therefore bravely rises to the challenge of re‐examining the entire currently available evidence, as rationally and as undogmatically as possible, by provocatively asking a carefully selected congregation of experts (who have never before jointly published on this controversial topic!) to discuss how essential anti‐desmoglein autoantibodies really are in the immunopathogenesis of PV. Not surprisingly, some of our expert ‘witnesses’ in this animated debate propose diametrically opposed answers to this question. While doing so, incisive additional questions are raised that relate to the central one posed, and our attention is called to facts that may deserve more careful consideration than they have received so far. Together with the intriguing (often still very speculative) complementary or alternative pathogenesis scenarios proposed in the following pages, this offers welcome ‘food for thought’ as well as very specific suggestions for important future research directions – within and beyond the camp of PV aficionados. The editors trust that this attempt at a rational public debate of the full evidence that is currently at hand will constructively contribute to further dissecting the exciting – and clinically very relevant! – immunopathogenesis of PV in all its complexity.


Journal of Investigative Dermatology | 2009

MicroRNA Expression in Melanocytic Nevi: The Usefulness of Formalin-Fixed, Paraffin-Embedded Material for miRNA Microarray Profiling

Martin Glud; Mikkel Klausen; Robert Gniadecki; Maria Rossing; Nina Hastrup; Finn Cilius Nielsen; Krzysztof T. Drzewiecki

MicroRNAs (miRNAs) are small, noncoding RNA molecules that regulate cellular differentiation, proliferation, and apoptosis. MiRNAs are expressed in a developmentally regulated and tissue-specific manner. Aberrant expression may contribute to pathological processes such as cancer, and miRNA may therefore serve as biomarkers that may be useful in a clinical environment for diagnosis of various diseases. Most miRNA profiling studies have used fresh tissue samples. However, in some types of cancer, including malignant melanoma, fresh material is difficult to obtain from primary tumors, and most surgical specimens are formalin fixed and paraffin embedded (FFPE). To explore whether FFPE material would be suitable for miRNA profiling in melanocytic lesions, we compared miRNA expression patterns in FFPE versus fresh frozen samples, obtained from 15 human melanocytic nevi. Out of microarray data, we identified 84 miRNAs that were expressed in both types of samples and represented an miRNA profile of melanocytic nevi. Our results showed a high correlation in miRNA expression (Spearman r-value of 0.80) between paired FFPE and fresh frozen material. The data were further validated by quantitative RT-PCR. In conclusion, FFPE specimens of melanocytic lesions are suitable as a source for miRNA microarray profiling.

Collaboration


Dive into the Robert Gniadecki's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Niels Ødum

University of Copenhagen

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Lone Skov

University of Copenhagen

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge