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1.
Nanoscale ; 10(26): 12564-12572, 2018 Jul 09.
Article in English | MEDLINE | ID: mdl-29932450

ABSTRACT

Next generation Li-ion batteries require improved energy densities, power output and safety to satisfy the demands of emerging technologies. All solid state 3D thin-film batteries (ASB) based on nanoionics are considered as frontrunners to enable all this. In order to facilitate the introduction of this new architecture, a homogeneous electrochemical activity and a high ionic diffusivity of the electrodes is key. However, nanometer-resolved techniques to probe structural, electrical and electrochemical properties of the battery components are still limited. Here we propose a study that combines conductive atomic force microscopy (C-AFM) and secondary ion mass spectrometry (SIMS) for structural and electrical characterization. In addition, a novel concept called ion-modulated C-AFM (imC-AFM) is introduced to also sense the electrochemical activity of ions in confined volumes. Using the aforementioned methodologies, LixMn2O4 thin film cathodes are studied observing: (1) a direct correlation between electrical conductivity and local chemistry. (2) A non-uniform Li-ion electrochemical activity (i.e. ionic conductivity) on the cathode's surface with a clear enhancement in grain boundaries (GBs). Finally, (3) imC-AFM observes a high volume expansion associated with high Li incorporation. This work introduces a novel pathway for the rapid analysis of materials to be used in ASB.

2.
Chem Sci ; 7(9): 5827-5832, 2016 Sep 01.
Article in English | MEDLINE | ID: mdl-30034722

ABSTRACT

We present a highly sensitive gas detection approach for the infamous 'nerve agent' group of alkyl phosphonate compounds. Signal transduction is achieved by monitoring the work function shift of metal-organic framework UiO-66-NH2 coated electrodes upon exposure to ppb-level concentrations of a target simulant. Using the Kelvin probe technique, we demonstrate the potential of electrically insulating MOFs for integration in field effect devices such as ChemFETs: a three orders of magnitude improvement over previous work function-based detection of nerve agent simulants. Moreover, the signal is fully reversible both in dry and humid conditions, down to low ppb concentrations. Comprehensive investigation of the interactions that lead towards this high sensitivity points towards a series of confined interactions between the analyte and the pore interior of UiO-66-NH2.

3.
Nanotechnology ; 25(50): 504008, 2014 Dec 19.
Article in English | MEDLINE | ID: mdl-25431990

ABSTRACT

Heterogeneous nanostructured electrodes using carbon nanosheets (CNS) and TiO2 exhibit high electronic and ionic conductivity. In order to realize the chip level power sources, it is necessary to employ microelectronic compatible techniques for the fabrication and characterization of TiO2-CNS thin-film electrodes. To achieve this, vertically standing CNS grown through a catalytic free approach on a TiN/SiO2/Si substrate by plasma enhanced chemical vapour deposition (PECVD) was used. The substrate-attached CNS is responsible for the sufficient electronic conduction and increased surface-to-volume ratio due to its unique morphology. Atomic layer deposition (ALD) of nanostructured amorphous TiO2 on CNS provides enhanced Li storage capacity, high rate performance and stable cycling. The amount of deposited TiO2 masks the underlying CNS, thereby controlling the accessibility of CNS, which gets reflected in the total electrochemical performance, as revealed by the cyclic voltammetry and charge/discharge measurements. TiO2 thin-films deposited with 300, 400 and 500 ALD cycles on CNS have been studied to understand the kinetics of Li insertion/extraction. A large potential window of operation (3-0.01 V); the excellent cyclic stability, with a capacity retention of 98% of the initial value; and the remarkable rate capability (up to 100 C) are the highlights of TiO2/CNS thin-film anode structures. CNS with an optimum amount of TiO2 coating is proposed as a promising approach for the fabrication of electrodes for chip compatible thin-film Li-ion batteries.

4.
Br J Dermatol ; 167(4): 778-86, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22564185

ABSTRACT

BACKGROUND: Digital dermoscopy has been shown to permit an earlier detection of melanoma. However, few studies have investigated its added value in reducing unnecessary excisions in everyday clinical practice. OBJECTIVES: To compare, in daily practice, the efficiency of three dermoscopy methods: dermoscopy alone with little training, dermoscopy alone with adequate training and dermoscopy with adequate training and access to digital dermoscopy, and to confirm the safety of this latter approach. METHODS: Thirty-six dermatologists working without digital dermoscopy were divided into two groups according to their training in dermoscopy. The third group constituted of two dermatologists working in a pigmented lesion clinic with access to the digital dermoscopy technique and eight additional dermatologists working in the same dermatology department. These 46 dermatologists included all presumed melanocytic lesions excised over a period of 1 year. The primary endpoint was the melanoma/nonmelanoma ratio (M/NM-R); secondary endpoints were the ratio of 'problem' naevi to common naevi (PN/CN-R), specificity and sensitivity for the diagnosis of melanoma, in situ/invasive melanoma ratio, and the mean Breslow thickness. RESULTS: In total, 1865 excised lesions, including 231 melanomas, were included. In the digital dermoscopy availability group (DD-G) the M/NM-R was significantly better (1/2.43), as was the PN/CN-R (1/1.48) (P < 0.001 in both cases). The specificity was significantly higher in the DD-G and significantly higher for trained examiners as compared with examiners with little training. More that one-third of all melanomas discovered by digital dermoscopy were in situ, and the mean Breslow thickness was 0.32 mm for the invasive ones. CONCLUSIONS: The reduction of unnecessary excisions when using digital dermoscopy compared with dermoscopy alone in our study suggests that access to digital dermoscopy offers a better management of pigmented lesions in daily practice. The high number of early lesions diagnosed by this technique confirms that its use is safe.


Subject(s)
Dermoscopy/methods , Melanoma/diagnosis , Nevus, Pigmented/diagnosis , Skin Neoplasms/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Dermoscopy/standards , Early Detection of Cancer/methods , Education, Medical, Continuing , Female , Humans , Image Interpretation, Computer-Assisted/methods , Image Interpretation, Computer-Assisted/standards , Male , Melanocytes , Melanoma/surgery , Middle Aged , Nevus, Pigmented/surgery , Risk Factors , Sensitivity and Specificity , Skin Neoplasms/surgery , Young Adult
5.
Rev Med Brux ; 33(1): 12-21, 2012.
Article in French | MEDLINE | ID: mdl-22512145

ABSTRACT

Mastocytosis is a heterogenous disorder due to abnormal proliferation and infiltration of mast cells in different tissues, primarily the skin and the bone marrow. Cutaneous mastocytosis is often benign and regresses spontaneously. Systemic mastocytosis is a chronic disease in which some types are indolent but other types such as mast cell leukemia are very aggressive. Pathogenesis of systemic mastocytosis involves a somatic mutation of the gene coding for the c-kit receptor, the most frequent mutation being D816V. Diagnostic criteria have been established by the WHO using histopathological, molecular and biochemical parameters. Treatment of systemic mastocytosis remains a challenge for the clinician due to variability and complexity of the disease. There is, in addition, a lack of a standard and efficient treatment. New targeted therapies with tyrosine kinase inhibitors directed against the c-kit receptor are currently being studied, with the purpose to act specifically on the " primum movens "of the disease. The current review provides an overview of pathogenesis, clinical presentation, diagnosis and classification of cutaneous and systemic mastocytosis. We also discuss the prognosis and the different treatments currently available according to the sub-type of mastocytosis.


Subject(s)
Mastocytosis, Cutaneous/diagnosis , Mastocytosis, Cutaneous/drug therapy , Mastocytosis, Systemic/diagnosis , Mastocytosis, Systemic/drug therapy , Biopsy, Fine-Needle , Bone and Bones/pathology , Diagnosis, Differential , Humans , Mastocytosis, Cutaneous/etiology
6.
Ann Dermatol Venereol ; 139(2): 91-102, 2012 Feb.
Article in French | MEDLINE | ID: mdl-22325747

ABSTRACT

BACKGROUND: The incidence of melanoma has been increasing for 50 years. Exposure to ultraviolet (UV) radiation constitutes the main risk factor. The aim of this study was to analyze the impact on hospital staff behaviour with regard to UV of screening campaigns initiated in Belgium 11 years ago. PATIENTS AND METHODS: We performed a multicentre, before-after study by sending an anonymous survey to the staff of four hospital in Brussels, from March 2010 to April 2010 (group 2: n=895). Demographic, clinical and behavioural data were collected and compared to those collected 23 years ago in the same hospitals (group 1: n=2410). RESULTS: Phototypes in both groups were similar. In group 2, the distribution of naevi tended to be spread over the whole body and the severity of sunburn had decreased. Group 2 participants reported a reduction in active sun exposure, especially in the past 10 years, with less leisure-time tanning. There was a significant increase in holidays in sunny locations, although vacation time was shorter, with prolonged daily and annual exposure. Sunscreens were more frequently used and there was an increase in sun-bed use, especially in beauty parlours. CONCLUSION: Our study comprises a double snapshot of a population of hospital workers at an interval of 23 years. The information and screening campaigns do not seem to have had the desired effect on the hospital staff surveyed. Sunscreen use has in fact resulted in extended UV exposure and the observed exposure pattern is that most frequently involved in melanoma development.


Subject(s)
Environmental Exposure , Health Behavior , Melanoma/prevention & control , Skin Neoplasms/prevention & control , Sunscreening Agents , Ultraviolet Rays , Adolescent , Adult , Aged , Aged, 80 and over , Belgium , Child , Environmental Exposure/adverse effects , Female , Humans , Male , Melanoma/etiology , Middle Aged , Skin Neoplasms/etiology , Ultraviolet Rays/adverse effects
7.
Nanotechnology ; 22(39): 395202, 2011 Sep 30.
Article in English | MEDLINE | ID: mdl-21891859

ABSTRACT

We investigate breakdown of carbon nanotube (CNT) interconnects induced by Joule heating in air and under high vacuum conditions (10(-5) mbar). A CNT with a diameter of 18 nm, which is grown by chemical vapor deposition to connect opposing titanium nitride (TiN) electrodes, is able to carry an electrical power up to 0.6 mW before breaking down under vacuum, with a corresponding maximum current density up to 8 × 10(7) A cm(-2) (compared to 0.16 mW and 2 × 10(7) A cm(-2) in air). Decoration with electrochemically deposited Ni particles allows protection of the CNT interconnect against oxidation and improvement of the heat release through the surrounding environment. A CNT decorated with Ni particles is able to carry an increased electrical power of about 1.5 mW before breaking down under vacuum, with a corresponding maximum current density as high as 1.2 × 10(8) A cm(-2). The Joule heating produced along the current carrying CNT interconnect is able to melt the Ni particles and promotes the formation of titanium carbon nitride which improves the electrical contact between the CNT and the TiN electrodes.

8.
Arch Dermatol Res ; 302(2): 131-7, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19547993

ABSTRACT

New topical immunomodulators have been reported to cause repigmentation of vitiligo lesions. However, time-kinetics of such repigmentation in different anatomic locations is not well known. We performed a randomized double-blind placebo control study with tacrolimus versus the vehicle and a nonrandomized control study with pimecrolimus to evaluate the time to reach significant pigmentation, its duration and extent in treated areas. Antioxidant status of serum was also assessed. Twenty patients, in the tacrolimus study, had one pair of lesions on different localizations, and 20 on face and/or upper limbs for pimecrolimus. The extent of repigmentation was evaluated by slides and mapmakings at baseline and every 4 weeks during 7 months. Adverse events were recorded. The derivatives of oxygen metabolites, the ferric reducing ability of serum and vitamin E were assessed. Three groups of patients were identified with the tacrolimus study. Eight had no significant change in response characterized by a parallel increase of repigmentation or none in treated and control areas. Nine had a better repigmentation to tacrolimus at fifth month of treatment. Three had a marked repigmentation in control areas at the end of treatment. Repigmentation was significant on the face compared to upper-limbs with pimecrolimus from fourth to seventh month. A significant reduction of oxidative stress and an increase in antioxidant capacity in serum of patients treated with topical tacrolimus was observed, while those treated with pimecrolimus did not show any significant changes but an increase in vitamin E. Our work defines three periods in repigmentation, triggering during the first 4 months, increase in pigmentation with tacrolimus and a plateau or a sustained repigmentation. The continuity of the treatment seems necessary to ensure a prolonged repigmenting effect and even an enhanced one, such as the one we observed on the face with pimecrolimus. The extent of repigmentation was more significant on the face compared to other locations probably due to differences in melanocyte density. Furthermore, we did not find any relationship between repigmentation and the duration of vitiligo. Tacrolimus was able to reduce the systemic oxidative stress independently from its repigmenting capacity. Both drugs were well tolerated.


Subject(s)
Skin Pigmentation/drug effects , Tacrolimus/analogs & derivatives , Tacrolimus/therapeutic use , Vitiligo/drug therapy , Adolescent , Adult , Aged , Antioxidants/therapeutic use , Double-Blind Method , Female , Humans , Male , Middle Aged , Oxidative Stress/drug effects , Tacrolimus/adverse effects , Vitiligo/metabolism
11.
J Eur Acad Dermatol Venereol ; 22(10): 1193-9, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18489566

ABSTRACT

BACKGROUND: Whereas teledermatology is an emerging discipline, to date, no teledermatology service has been developed, which is specifically dedicated to black skins. OBJECTIVES: To create and develop a teledermatology service that provides a complete range of communication, information, telediagnosis and teaching services. METHODS: A multilingual clinical description of the lesion was provided for each photograph using a five-level disease classification from the 10th revised International Classification of Diseases. In parallel, a usability study to assess and improve the functionality of the platform was also conducted. RESULTS: A web prototype has been developed which integrates image acquisition, submission, clinical description, translation as well as validation, security and data protection aspects and almost 2000 images were obtained from which 600 have been integrated in the 'store and forward' telemedicine system (http://www.black-skin.org). Initial usability tests with native French medical students show good perceived usefulness, perceived usability and internal consistency (Cronbach's alpha = 0.80 and 0.84). CONCLUSION: The Black Skin project (North and South collaboration project) offers possibilities for continuous medical education (pedagogical cases), teleteaching (educational quiz) or asking for a second opinion ('Ask a specialist' item).


Subject(s)
Black People , Cooperative Behavior , Dermatology , Internet , Skin Diseases/ethnology , Telemedicine , Belgium , Humans , Skin Diseases/diagnosis , Skin Diseases/pathology
13.
Am J Transplant ; 8(3): 688-96, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18261182

ABSTRACT

Skin rejection after hand transplantation is characterized by a maculopapular erythematous rash that may be diffuse, patchy or focal, and distributed over forearms and dorsum of the hands. This 'classical' pattern of rejection usually spares the skin of the palm and does not affect the nails. Herein, we report the experience on four cases presenting with an 'atypical' pattern of rejection that is novel in involving the palmar skin and the nails. All patients were young and exposed to repetitive and persistent mechanical stress of the palm. Characteristic features of rejection included a desquamative rash associated with dry skin, red papules, scaling and lichenification localized to the palm. Skin lesions were associated with nail dystrophy, degeneration, deformation or loss. Histology of the skin and nail bed revealed a lymphocytic infiltrate with predominance of T cells (CD3+, CD4+ and CD8+), with small numbers of B cells (CD20+ and CD79a+) and a low number of Forkhead transcription factor 3 (FOXP3)-positive cells in one patient. The lesions persisted over weeks to months, responded poorly to steroid treatment and were managed with antithymocyte globulin (ATG; Thymoglobulin, Genzyme, Cambridge, MA), alemtuzumab and/or intensified maintenance immunosuppression.


Subject(s)
Graft Rejection/pathology , Hand Transplantation , Skin/pathology , Adult , Antigens, CD/analysis , B-Lymphocytes/immunology , Graft Rejection/diagnosis , Graft Rejection/drug therapy , Humans , Immunosuppression Therapy , Male , Skin/immunology , T-Lymphocytes/immunology
14.
Rev Med Brux ; 29(6): 552-8, 2008.
Article in French | MEDLINE | ID: mdl-19202711

ABSTRACT

The epidermal growth factor receptor (EGFR) is overexpressed in many solid tumors. Its inactivation has an inhibitory effect on the growth and spread of the tumoral cells. It therefore represents an attractive target to treat different cancers. Several molecules have already been registered while others are still under evaluation. One of the common side effects of these therapies is the development of cutaneous toxicities, more precisely a cutaneous rash, sometimes major and distressing. The physiopathology of these cutaneous side effects is poorly understood. Moreover a correlation between the severity of the rash and the tumoral response has been demonstrated in some studies. If this link is confirmed, the rash could be used as a marker for the anti-tumoral activity. This review will summarize the clinical presentations and the current recommendations for the management of cutaneous toxicities induced by EGFR inhibitors.


Subject(s)
ErbB Receptors/antagonists & inhibitors , Skin/pathology , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal, Humanized , Antineoplastic Agents/adverse effects , Antineoplastic Agents/therapeutic use , Cetuximab , ErbB Receptors/genetics , Humans , Neoplasms/drug therapy , Neoplasms/genetics , Neoplasms/pathology , Skin/drug effects
15.
Rev Med Brux ; 28(5): 445-51, 2007.
Article in French | MEDLINE | ID: mdl-18069519

ABSTRACT

Extracorporeal photochemotherapy is an immunomodulatory treatment wich is carried out in three steps: first leukapheresis, then ex vivo PUVA treatment and finally autologous transfusion. Its current "evidence-based" indications are erythrodermic cutaneous lymphoma, graft versus host disease and cardiac graft rejection. However this treatment has already been used with success in many other diseases such as systemic sclerosis, multiple sclerosis, type 1 diabetes and various autoimmune dermatologic diseases. Randomised controlled studies are needed to confirm the efficacy of photopheresis in these diseases. We also review the different hypotheses explaining the mechanism of action of photopheresis.


Subject(s)
Lymphoma, T-Cell, Cutaneous/radiotherapy , Photopheresis/methods , Autoimmune Diseases/etiology , France , Graft Rejection/etiology , Graft vs Host Disease/etiology , Humans , Inflammation/etiology , Leukapheresis , Photopheresis/adverse effects , United States
16.
Arch Dermatol Res ; 299(10): 483-6, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17934742

ABSTRACT

Dendritic cell (DC) vaccines are used for the induction of anti-tumor T cell reaction in melanoma patients. DC are generated in vitro, pulsed with antigen and matured prior to injection. They are supposed to migrate to lymph nodes and to present the processed antigen to naive T cells allowing activation of tumor-specific lymphocytes. It has been suggested that intradermal injection allows a superior migration to the lymph node. Eight HLA-A2 positive patients with stage III or IV melanomas expressing NA 17 antigen were collected. They were included in a pilot trial of vaccination in which they received IL3/INFb DC presenting the NA17 A2 antigen. In each patient, a skin biopsy was performed at the injection site, 24 h after inoculation. The striking features of the biopsies were the presence of a perivascular CD3+/CD8+ T cell infiltrate with a slight population of CD4+ cells and the presence of a massive neutrophilic infiltrate associated with the injected DC still present, realizing a suppurative granuloma. The persistence of DC 24 h after the injection suggests that migration in the lymph node is not necessary for the induction of the immune response. The skin itself could be the location of a reaction starting with a massive recruitment of neutrophils.


Subject(s)
Immunotherapy, Adoptive/methods , Langerhans Cells/immunology , Melanoma/therapy , Neutrophils/immunology , Skin Neoplasms/therapy , Adolescent , Adult , Aged , Biopsy , Cell Movement , Granuloma/immunology , Humans , Injections, Intradermal , Lymph Nodes/immunology , Lymphocyte Activation , Melanoma/immunology , Middle Aged , Pilot Projects , Skin Neoplasms/immunology , T-Lymphocytes/immunology
17.
Rev Med Brux ; 28(4): 336-44, 2007 Sep.
Article in French | MEDLINE | ID: mdl-17958030

ABSTRACT

Psoriasis is a frequent chronic disease with a typical cutaneous expression described as erythemato-squamous lesions, and sometimes, joint involvement. This disorder rarely causes death in patients, but often alters their quality of life. A better understanding of the pathophysiology of psoriasis has led to the development of new therapeutic options among which are treatments targeted on blocking T-cell activation. Thanks to these therapies we can offer the patients long lasting remission, albeit not a curative approach. The therapeutic approach towards psoriasis will be selected in a multidisciplinary spirit, and after considering the patient himself, his disease and his lifestyle.


Subject(s)
Psoriasis/drug therapy , Antibodies, Monoclonal/therapeutic use , Etanercept , Gout/physiopathology , Humans , Immunoglobulin G/therapeutic use , Infliximab , Lymphocyte Activation/drug effects , Lymphocytes/physiology , Psoriasis/classification , Psoriasis/immunology , Psoriasis/physiopathology , Receptors, Tumor Necrosis Factor/therapeutic use , Surveys and Questionnaires , T-Lymphocytes/immunology
19.
J Eur Acad Dermatol Venereol ; 21(6): 771-6, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17567306

ABSTRACT

BACKGROUND: Breast cancer is the most common cancer in women and therefore represents a major problem in public health. Data from patients' self-report questionnaires provide valuable information about the side-effects that patients may view as having a significantly detrimental impact on their quality of life (QOL) and yet are not always recognized as important by healthcare professionals. Cosmetology is a specific care for patients and there is actually no scientific evidence regarding effects on QOL for women with breast cancer. OBJECTIVE: The purpose of this study is to assess the impact of cosmetic care on QOL in breast cancer patients during chemotherapy and radiotherapy. METHODS: We developed a prospective, multicentre, randomized, controlled study including 27 patients. All the patients had to fill in a French-validated dermatologic specific quality-of-life questionnaire to compare the QOL of the two groups, the cosmetic group and the control group, at three different times of the adjuvant treatment. RESULTS: The results show a statistically significant difference between the cosmetic group and the control group in two areas of QOL: mood state and self-perception of the disease. CONCLUSION: This study emphasizes the interest of cosmetic care in breast cancer patients. However, further larger trials are needed to confirm this study.


Subject(s)
Breast Neoplasms/psychology , Cosmetic Techniques , Quality of Life , Skin Care/methods , Adult , Breast Neoplasms/drug therapy , Breast Neoplasms/radiotherapy , Female , France , Humans , Middle Aged , Prospective Studies , Surveys and Questionnaires
20.
Acta Chir Belg ; 107(2): 205-7, 2007.
Article in English | MEDLINE | ID: mdl-17515272

ABSTRACT

Cutaneous Fluorescence Diagnosis (FD) is a new promising dermatological procedure which is based on the combination of a local application of a photosensitizer such as 5-aminolevulinic acid (ALA) or its methyl ester (MAL) and the use of a light source (red light) adapted to the absorption spectrum of these molecules. The targeted photosensitization of skin cancers, particularily superficial and extensive lesions including superficial basal cell carcinoma and Bowen's disease, by ALA or MAL induced porphyrins leads to a selective red fluorescence which can be demonstrated by Wood's lamp. This technique may be useful either to define better the choice of margins or to detect earlier and or multifocal recurrences.


Subject(s)
Carcinoma, Basal Cell/diagnosis , Carcinoma, Basal Cell/therapy , Fluorescence , Skin Neoplasms/diagnosis , Skin Neoplasms/therapy , Adult , Aged , Aminolevulinic Acid/analogs & derivatives , Aminolevulinic Acid/therapeutic use , Female , Humans , Male , Middle Aged , Photochemotherapy , Photosensitizing Agents/therapeutic use , Porphyrins
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