Toxic Epidermal Necrolysis and Graft-versus-Host Reaction: Revisiting a Puzzling Similarity.
PIERARD, Gérald ; Hermanns-Lê, Trinh ; PAQUET, Philippe et al
in ISRN Dermatology (2013)Detailed reference viewed: 16 (1 ULg)
Intense pulsed-light therapy for proliferative superficial strawberry haemangiomas of infancy.
CAUCANAS, Marie ; PAQUET, Philippe ; HENRY, Frédérique et al
in Case Reports in Dermatological Medicine (2011), 2011(art.253607), 1-5Detailed reference viewed: 29 (5 ULg)
New approaches in light/laser therapies and photodynamic treatment of acne.
; PAQUET, Philippe ; PIERARD, Gérald
in Expert Opinion on Pharmacotherapy (2011), 12(4), 493-501
Acne is a domain in which the technology and understanding of light/laser therapeutic procedures have advanced considerably. The aim of the paper was to revisit adjunctive physical treatments of acne ... [more ▼]
Acne is a domain in which the technology and understanding of light/laser therapeutic procedures have advanced considerably. The aim of the paper was to revisit adjunctive physical treatments of acne, including light/laser treatments and photodynamic therapy. This review summarizes findings about such treatment modalities with particular emphasis on efficacy and safety. A number of laser/light-based modalities have been developed to meet the increasing demand for new acne treatments. The current devices correspond, on the one hand, to light-emitting diode therapy and, on the other hand, to the 532-nm potassium titanyl phosphate laser, the 585- and 595-nm pulsed dye laser, the 1450-nm diode laser, the 1320-nm Nd:YAG laser and intense pulsed light. Photodynamic therapy is also available. It is claimed that light/laser treatments might induce a faster response compared with the 1-3 months needed for response to traditional oral and topical treatments. In conclusion, pulsed dye laser shows efficacy in some patients with mild to moderate acne. The relative effectiveness compared with other treatments is unconfirmed; from the published information, evidence-based efficacy assessment of light/laser therapies in acne remains almost impossible. [less ▲]Detailed reference viewed: 12 (2 ULg)
La peau du patient sous chimiothérapie anticancéreuse.
PIERARD, Gérald ; PAQUET, Philippe ; FRANCHIMONT, Claudine et al
in Dermatologie Actualité (2011), 124
Des effets cutanés indésirables peuvent survenir lors de chimiothérapies anticancéreuses. La morbidité peut être handicapante à des degrés divers. Certaines manifestations sont graves comme celles ... [more ▼]
Des effets cutanés indésirables peuvent survenir lors de chimiothérapies anticancéreuses. La morbidité peut être handicapante à des degrés divers. Certaines manifestations sont graves comme celles rencontrées lors de nécroses épithéliales et/ou vasculaires étendues. D’autres sont spécifiques à l’agent administré. Tel est le cas pour des éruptions acnéiformes induites par les antagonistes de l’EGFR. Dans la grande majorité des cas, les altérations de la structure de la couche cornée et de ses fonctions se résument seulement à un état de xérose. Parfois aussi, les altérations ne se décèlent qu’à l’examen histopathologique sans répercussion clinique manifeste. Pour chaque patient concerné, il convient d’identifier avec précision les effets indésirables de la chimiothérapie anticancéreuse afin de choisir les moyens les plus adéquats pour prévenir leur aggravation et les traiter au mieux. L’apport de l’examen dermatopathologique standard et fonctionnel est précieux au stade du diagnostic. [less ▲]Detailed reference viewed: 47 (4 ULg)
Mechanobiology and cell tensegrity: the root of ethnic hair curling?
; PAQUET, Philippe ; QUATRESOOZ, Pascale et al
in Journal of Cosmetic Dermatology (2011), 10(2), 163-7
BACKGROUND: The hair shape, either straight, crimp, or curly, is basically under genetic influence. It is possibly altered by some drugs such as cytostatic agents. In addition, specific innate molecular ... [more ▼]
BACKGROUND: The hair shape, either straight, crimp, or curly, is basically under genetic influence. It is possibly altered by some drugs such as cytostatic agents. In addition, specific innate molecular characteristics are modulated by some cosmetic procedures to reshape the hair shafts. AIM: To revisit the possible implication of mechanobiology and cell tensegrity in shaping ethnic hair. MATERIALS AND METHODS: Optical and scanning electron microscopy of hairs. RESULTS: It is generally held that the cross-section shape of hair is related to differences in the global aspect of the hair shaft. A possible biologic link between these features may rely on shaping cell tensegrity at any portion of the hair shaft. Cell tensegrity encompasses all intrinsic and extrinsic forces responsible for the three-dimensional arrangement of intracellular macromolecules. CONCLUSION: We offer as a hypothesis that the hair shape in part depends on the organization of the cell proliferation in the hair matrix. This review gathers observations supporting the involvement of cell tensegrity in shaping the hair shaft. [less ▲]Detailed reference viewed: 12 (1 ULg)
Photoaging under recreational sunbeds.
QUATRESOOZ, Pascale ; HENRY, Frédérique ; PAQUET, Philippe et al
in Skin Research & Technology (2011)
Background: Artificial sources of restricted light wavelength, particularly tanning beds, are progressively gaining importance in photoaging. Objective: To assess the kinetics and the long-term evolution ... [more ▼]
Background: Artificial sources of restricted light wavelength, particularly tanning beds, are progressively gaining importance in photoaging. Objective: To assess the kinetics and the long-term evolution of skin pigmentation and tensile functions in sunbed worshippers over a period of 8 years. Methods: Photoaging was explored in women who were both sunshine and sunbed worshippers. A series of 65 phototype III women aged 31-46 years completed a 100-month survey. Quarterly assessments were performed on the forearms to measure (a) the skin color individual typology angle (ITA degrees ), (b) the extent in mottled subclinical melanoderma (MSM) using the ultraviolet light-enhanced visualization method and (c) the rheological properties of skin. Results: A progressive increase in both skin extensibility and hysteresis was observed, contrasting with a decrease in biologic elasticity. These rheological changes were correlated with the ITA degrees changes, but not with the MSM extent. The kinetics of evolution of each test variable were distinct over time. Discussion: This work is the first attempt at evaluating the kinetics of changes in physical parameters during a long period of frequent exposures to tanning sunbeds and sunshine for lifestyle purposes. The alterations were quite important in the color, MSM and rheological functions of the skin. [less ▲]Detailed reference viewed: 18 (5 ULg)
Pre-study and in-study validation of a SPE-LC-MS-MS method for the determination of 5-S-cysteinyldopa, a melanoma biomarker, in human plasma.
; Mansion, François ; Houbart, Virginie et al
in Talanta (2011), 84(2), 280-6
The incidence of malignant melanoma has increased over the past decades, particularly in Caucasian population. This disease presents defavourable prognosis in terms of survey, especially when detection ... [more ▼]
The incidence of malignant melanoma has increased over the past decades, particularly in Caucasian population. This disease presents defavourable prognosis in terms of survey, especially when detection occurs at the metastatic phase. Reliable analytical methods for biomarker determination are thus an interesting tool in pathology detection and follow-up. In this context, a method using SPE-LC-ESI-MS-MS for the determination of 5-S-cysteinyldopa (5-SCD) in human plasma was optimized. The presence of matrix effect was investigated in details while 5-SCD stability was studied according to FDA requirements for the validation of bioanalytical methods. Pre-study and in-study validations of the entire method were then successfully performed by applying the approach based on total measurement error and accuracy profiles over a concentration ranges from 1.6 to 200 ng/ml. Good results with respect to accuracy, trueness and precision were obtained. The maximum risk of observing future measurements falling outside the acceptance limits during routine analysis was also estimated. [less ▲]Detailed reference viewed: 22 (7 ULg)
Immunohistochemical Aspects of the Fibrogenic Pathway in Nephrogenic Systemic Fibrosis.
Quatresooz, Pascale ; Paquet, Philippe ; Hermanns-Le, Trinh et al
in Applied Immunohistochemistry & Molecular Morphology (2010)
Nephrogenic systemic fibrosis (NSF) is a rare gadolinium-dependent disorder of the skin and viscera. The aim of this study was to revisit some immunopathologic clues of NSF, including the characterization ... [more ▼]
Nephrogenic systemic fibrosis (NSF) is a rare gadolinium-dependent disorder of the skin and viscera. The aim of this study was to revisit some immunopathologic clues of NSF, including the characterization of glycosaminoglycans, cell tensegrity, and cell proliferation in the dermis. Immunohistochemistry was done using antibodies directed to vimentin, CD34, Factor XIIIa, calprotectin, alpha-smooth muscle actin, Ulex europaeus agglutinin-1 (UEA-1), and MIB1/Ki67 and to glycosaminoglycans, including CD44 var3, versican, and perlecan. The vimentin+ cell density was markedly increased. The vast majority of them corresponded to CD34+ or Factor XIIIa+ dermal dendrocytes (DD) showing distinct cell tensegrity. CD34+DD were slender, elongated, and usually scattered in the dermis but focally clustered in nodular collections. By contrast, Factor XIIIa+ was plump with squat dendrites showing no evidence for being under mechanical stress. Cells in the vicinity of the microvasculature were rounded and exhibited calprotectin immunoreactivity typical for monocyte/macrophages. The microvasculature highlighted by UEA-1 and alpha-smooth muscle actin looked unremarkable. The cell proliferation highlighted by the MIB/Ki67 immunoreactivity was unusually high (>20%) in the interstitial stromal cells. Stromal cells enriched in versican were plump, abundant, and seemed interconnected each other by a dense network of dendrites. By contrast, the immunolabeling for perlecan and CD44 var 3 was unremarkable. In conclusion, the cell population involved in NSF seemed phenotypically heterogeneous, and its growth fraction was clearly boosted in the skin. The intracellular load in versican was prominent. The aspect of cell tensegrity did not suggest the influence of mechanical stress putting stromal cells under tension in the dermis. [less ▲]Detailed reference viewed: 11 (3 ULg)
L'image du mois. Calcinose idiopathique du scrotum.
Paquet, Philippe ; ; Szepetiuk, Grégory et al
in Revue Médicale de Liège (2010), 65(3), 113-4Detailed reference viewed: 80 (4 ULg)
La keratose actinique au diapason de la photocarcinogenese en champs. Un concept revisite.
QUATRESOOZ, Pascale ; PAQUET, Philippe ; PIERARD, Gérald
in Revue Médicale de Liège (2010), 65(11), 619-22
Actinic keratosis should no more be considered as a single neoplasm calling for an individual treatment. The concept of actinic photocarcinogenesis presently turns upside down the perception of skin ... [more ▼]
Actinic keratosis should no more be considered as a single neoplasm calling for an individual treatment. The concept of actinic photocarcinogenesis presently turns upside down the perception of skin cancers induced by nonionizing electromagnetic radiations. Currently, the clinician should cope with the whole skin area that has been damaged by chronic exposures to the visible and the invisible spectrum of the light. The therapeutic archetypes are 5-fluorouracile 5% and imiquimod 5% carefully applied to the skin area. [less ▲]Detailed reference viewed: 10 (0 ULg)
Characterization of the skin using capacitance imaging.
Xhauflaire, Emmanuelle ; Paquet, Philippe ; Quatresooz, Pascale et al
in Expert Review of Dermatology (2010), 5Detailed reference viewed: 12 (1 ULg)
Facing towards epidermal stem cells (Review).
; Pierard, Gérald ; Paquet, Philippe et al
in International Journal of Molecular Medicine (2010), 26(2), 171-4
Skin contains somatic stem cells that generate keratinocyte, melanocyte and mesenchymal cell lineages. These somatic stem cells have traditionally been thought to be restricted in their differentiation ... [more ▼]
Skin contains somatic stem cells that generate keratinocyte, melanocyte and mesenchymal cell lineages. These somatic stem cells have traditionally been thought to be restricted in their differentiation and regeneration potential to the tissues in which they reside. This review focused on epidermal stem cells (ESCs). These cells are distinguished from transitory amplifier cells and post-mitotic cells. ESC are found in the interadnexal epidermis and in the bulge region of hair follicles. A series of ESCs markers are available, but increased sensitivity and specificity require further development. [less ▲]Detailed reference viewed: 50 (4 ULg)
The therapeutic potential of TNF-alpha antagonists for skin psoriasis comorbidities.
Pierard, Gérald ; Pierard, Claudine ; Szepetiuk, Grégory et al
in Expert Opinion on Biological Therapy (2010), 10(8), 1197-208
IMPORTANCE OF THE FIELD: Alopecia, psoriatic arthritis, the metabolic syndrome, inflammatory bowel diseases and cardiovascular diseases may occur as skin psoriatic comorbidities. TNF-alpha antagonists are ... [more ▼]
IMPORTANCE OF THE FIELD: Alopecia, psoriatic arthritis, the metabolic syndrome, inflammatory bowel diseases and cardiovascular diseases may occur as skin psoriatic comorbidities. TNF-alpha antagonists are used to treat psoriasis. Adalimumab is one of the recognized active agents for this indication. AREAS COVERED IN THIS REVIEW: The current peer-reviewed publications and presentation of original findings. WHAT THE READER WILL GAIN: Adalimumab is active on recalcitrant psoriasis and some of its comorbidities, particularly arthropathies and Crohn's disease. However, the progression of the radiological alterations is limited with regression of the bony erosions. Psoriatic enthesopathy also regresses. Mortality associated with psoriasis arthropathy is on the decline. Crohn's disease, the most frequent inflammatory bowel comorbidity of psoriasis, is responsive to adalimumab. The effect of adalimumab on the metabolic syndrome and cardiovascular involvement is more erratic. The spectacular effects of adalimumab may be associated with some adverse effects. In particular, despite a marked reduction in the psoriasis area-and-severity index (PASI) score some new acute lesions of cutaneous psoriasis may develop corresponding to paradoxical psoriasis. Other potential adverse effects include infections, granulomas, rapid growth of cancers and occurrence of lymphomas. TAKE HOME MESSAGE: Adalimumab frequently controls moderate-to-severe forms of cutaneous psoriasis and some of its comorbidities. [less ▲]Detailed reference viewed: 26 (3 ULg)
Complications des comblements de rides et de volumateurs faciaux.
Paquet, Philippe ; Uhoda, Emmanuelle ; Quatresooz, Pascale et al
in Dermatologie Actualité (2010), 119Detailed reference viewed: 13 (2 ULg)
Functionally active macrophage-derived myeloperoxidase in the skin of drug-induced toxic epidermal necrolysis.
Paquet, Philippe ; ; Pierard, Gérald
in Dermatology : International Journal for Clinical & Investigative Dermatology (2010), 220(3), 201-7
BACKGROUND: Drug-induced toxic epidermal necrolysis (TEN) probably results from a complex and specific immune cell reaction involving lymphocytes and macrophages. OBJECTIVE: To assess the functional role ... [more ▼]
BACKGROUND: Drug-induced toxic epidermal necrolysis (TEN) probably results from a complex and specific immune cell reaction involving lymphocytes and macrophages. OBJECTIVE: To assess the functional role of macrophages in TEN. METHODS: Immunohistochemistry was performed on biopsies from early blisters developed in 9 TEN patients. The amount of extracellular myeloperoxidase (MPO) was measured by ELISA in TEN blister fluid and serum. Controls were blister fluids taken from 9 second-degree burns. In addition, 3-chlorotyrosine (a specific marker of MPO activity) was searched for using liquid mass chromatography both in TEN and burn blister fluids. RESULTS: Immunohistochemistry revealed numerous CD68+ macrophages in 8/9 TEN patients; 5-20% of these cells and rare CD15+ neutrophils exhibited MPO immunoreactivity, while keratinocytes were negative. The amount of MPO was significantly higher in TEN blister fluid than in TEN serum, suggesting macrophage production of MPO in the skin. In addition, MPO was significantly more abundant in TEN blister fluid than in burn blister fluid. 3-Chlorotyrosine was detected in 7/9 TEN blister fluids, but in only 2/9 burn blister fluids. DISCUSSION: MPO produced by macrophages was functionally active in most TEN patients, leading to the production of hypochlorous acid, a potent oxidative compound that alters keratinocytes. [less ▲]Detailed reference viewed: 28 (0 ULg)
New insights in toxic epidermal necrolysis (Lyell's syndrome): clinical considerations, pathobiology and targeted treatments revisited.
Paquet, Philippe ; Pierard, Gérald
in Drug Safety : An International Journal of Medical Toxicology & Drug Experience (2010), 33(3), 189-212
Drug-induced toxic epidermal necrolysis (TEN), also known as Lyell's syndrome, is a life-threatening drug reaction characterized by extensive destruction of the epidermis and mucosal epithelia. The eyes ... [more ▼]
Drug-induced toxic epidermal necrolysis (TEN), also known as Lyell's syndrome, is a life-threatening drug reaction characterized by extensive destruction of the epidermis and mucosal epithelia. The eyes are typically involved in TEN. At present, the disease has a high mortality rate. Conceptually, TEN and the Stevens-Johnson syndrome are closely related, although their severity and outcome are different. Distinguishing TEN from severe forms of erythema multiforme relies on consideration of aetiological, clinical and histological characteristics. The current understanding of the pathomechanism of TEN suggests that keratinocytes are key initiator cells. It is probable that the combined deleterious effects on keratinocytes of both the cytokine tumour necrosis factor (TNF)-alpha and oxidative stress induce a combination of apoptotic and necrotic events. As yet, there is no evidence indicating the superiority of monotherapy with corticosteroids, ciclosporin (cyclosporine) or intravenous immunoglobulins over supportive care only for patients with TEN. However, the current theory of TEN pathogenesis supports the administration of a combination of antiapoptotic/antinecrotic drugs (e.g. anti-TNF-alpha antibodies plus N-acetylcysteine) targeting different levels of the keratinocyte failure machinery. [less ▲]Detailed reference viewed: 31 (0 ULg)
Angiogenic fast-growing melanomas and their micrometastases.
Quatresooz, Pascale ; Pierard, Claudine ; Paquet, Philippe et al
in European Journal of Dermatology (2010), 20(3), 302-7
Malignant melanoma (MM), particularly its fast-growing type, is prone to interstitial, intravascular and extravascular migratory metastases. There is no information linking their growth fraction, the ... [more ▼]
Malignant melanoma (MM), particularly its fast-growing type, is prone to interstitial, intravascular and extravascular migratory metastases. There is no information linking their growth fraction, the configuration of the MM advancing edge, the extent in vascularity and the propensity to metastatic progression. The objective of this study was to determine the growth fraction, the size of vascularity and the contours of the progression border of 32 fast-growing MM with regard to the presence or absence of a micrometastatic spread inside the skin and overt metastases in the sentinel lymph nodes. In vivo high resolution colorimetry was performed as a clinical estimate of MM vascularity. Euclidean geometry and fractal analysis were used on immunohistochemical sections. The relative microvasculature profile area beneath MM, and the fractal dimension D of the MM frontline were assessed. The MIB/Ki-67 index was determined in MM cells. Value a* of colorimetry was similarly increased in the presence or absence of micro-metastases. No difference in growth fraction was revealed between these neoplasms. Correlations were found between vascularity and angiotropism, and between the micrometastatic process and the sentinel lymph node involvement. By contrast, no correlation was shown between vascularity and the fractal D dimension of the MM advancing edge. In sum, this study establishes a link between the extent of MM growth fraction, vascularity and the presence of dermal and nodal micrometastases in fast-growing MM. [less ▲]Detailed reference viewed: 21 (5 ULg)