Chain dynamics of human dermis by Thermostimulated currents: A tool for new markers of aging.

BACKGROUND/PURPOSE: The purpose of this clinical study was to identify dielectric markers to complete a previous thermal and vibrational study on the molecular and organizational changes in human dermis during intrinsic and extrinsic aging. METHODS: Sun-exposed and non-exposed skin biopsies were collected from 28 women devised in two groups (20-30 and ≥60 years old). The dielectric relaxation modes associated with localized and delocalized dynamics in the fresh and dehydrated state were determined by the Thermostimulated currents technique (TSC). RESULTS: Intrinsic and extrinsic aging induced significant evolution of some of the dielectric parameters of localized and delocalized dynamics of human skin. With photo-aging, freezable water forms a segregated phase in dermis and its dynamics is close to free water, what evidences the major role of extrinsic aging on water organization in human skin. Moreover, TSC indicators highlight the restriction of localized mobility with intrinsic aging due to glycation, and the cumulative effect of chronological aging and photo-exposition on the molecular mobility of the main structural proteins of the dermis at the mesoscopic scale. CONCLUSION: TSC is a well-suited technique to scan the molecular mobility of human skin. It can be uses as a relevant complement of vibrational and thermal characterization to follow human skin modifications with intrinsic and extrinsic aging.

Dermatology today and tomorrow: from symptom control to targeted therapy.

For many decades and until recently, medical approach to dermatologic diseases has been based on the physician's ability to recognize and treat symptoms. Nowadays, advances in the understanding of the biology of diseases and in technologies for intervening against them have allowed physicians to diagnose and treat underlying disease processes rather than simply addressing the symptoms. This means that rather than addressing 'the disease in humans', physicians can now address the particular pathologic (biologic, molecular) disturbance as it presents in the individual patient, i.e., physicians now can practice something much closer to 'personalized medicine', leading to greater benefits for the patients and the health of society in general. The deeper understanding of ultraviolet radiation, the importance of photoprotection and increased knowledge about signalling pathways of melanoma and carcinoma have led to more complete care for the dermatologic patient. The current popularity for excessive exposure to the sun, without adequate application of the appropriate photoprotection remedies, is the origin of melanoma, but also for the weakening of the structure and functions of the skin. Indeed, fragility of the skin can affect humans around the world. In the senior population, this skin fragility is accompanied by pruritus, whereas atopic dermatitis is an inflammatory disease with highest prevalence in children and adolescents. Acne, the number one reason for dermatologic consultations worldwide, increases its prevalence in adolescents and in females. Senescent alopecia affects humans after menopause and andropause. The articles in this publication present an overview of the current advanced understanding of the diagnosis and therapeutic approaches in 6 fields of dermatology - dermatopaediatry and gerontodermatology, oncodermatology, hair loss, atopic dermatitis, photoprotection and acne - and thereby serve as a useful compendium of updated information and references for all healthcare professionals who see patients with presentations of the symptoms of these diseases.

Nfkb1 is a haploinsufficient DNA damage-specific tumor suppressor.

NF-κB proteins play a central and subunit-specific role in the response to DNA damage. Previous work identified p50/NF-κB1 as being necessary for cytotoxicity in response to DNA alkylation damage. Given the importance of damage-induced cell death for the maintenance of genomic stability, we examined whether Nfkb1 acts as a tumor suppressor in the setting of alkylation damage. Hprt mutation analysis demonstrates that Nfkb1(-/-) cells accumulate more alkylator-induced, but not ionizing radiation (IR)-induced, mutations than similarly treated wild-type cells. Subsequent in vivo tumor induction studies reveal that following alkylator treatment, but not IR, Nfkb1(-/-) mice develop more lymphomas than similarly treated Nfkb1(+/+) animals. Heterozygous mice develop lymphomas at an intermediate rate and retain functional p50 in their tumors, indicating that Nfkb1 acts in a haploinsufficient manner. Analysis of human cancers, including therapy-related myeloid neoplasms, demonstrates that NFKB1 mRNA expression is downregulated compared with control samples in multiple hematological malignancies. These data indicate that Nfkb1 is a haploinsufficient, pathway-specific tumor suppressor that prevents the development of hematologic malignancy in the setting of alkylation damage.

VHL inactivation is an important pathway for the development of malignant sporadic pancreatic endocrine tumors.

A small subset of familial pancreatic endocrine tumors (PET) arises in patients with von Hippel-Lindau syndrome and these tumors may have an adverse outcome compared to other familial PET. Sporadic PET rarely harbors somatic VHL mutations, but the chromosomal location of the VHL gene is frequently deleted in sporadic PET. A subset of sporadic PET shows active hypoxia signals on mRNA and protein level. To identify the frequency of functionally relevant VHL inactivation in sporadic PET and to examine a possible prognostic significance we correlated epigenetic and genetic VHL alterations with hypoxia signals. VHL mutations were absent in all 37 PETs examined. In 2 out of 35 informative PET (6%) methylation of the VHL promoter region was detected and VHL deletion by fluorescence in situ hybridization was found in 14 out of 79 PET (18%). Hypoxia inducible factor 1alpha (HIF1-alpha), carbonic anhydrase 9 (CA-9), and glucose transporter 1 (GLUT-1) protein was expressed in 19, 27, and 30% of the 152 PETs examined. Protein expression of the HIF1-alpha downstream target CA-9 correlated significantly with the expression of CA-9 RNA (P<0.001), VHL RNA (P<0.05), and VHL deletion (P<0.001) as well as with HIF1-alpha (P<0.005) and GLUT-1 immunohistochemistry (P<0.001). These PET with VHL alterations and signs of hypoxia signalling were characterized by a significantly shortened disease-free survival. We conclude that VHL gene impairment by promoter methylation and VHL deletion in nearly 25% of PET leads to the activation of the HIF-pathway. Our data suggest that VHL inactivation and consecutive hypoxia signals may be a mechanism for the development of sporadic PET with an adverse outcome.

A multitechnique evaluation of topical corticosteroid treatment.

BACKGROUND/PURPOSE: Corticosteroids are widely prescribed for systemic or local treatment of inflammatory autoimmune disorders. Long-term therapy is associated with side effects and causes cutaneous atrophy of the epidermis and the dermis. The present study aims to evaluate with several noninvasive techniques, the skin modifications observed during corticosteroids treatment. The potential of skin mechanical measurement and ultrasound radio frequency (RF) signal analysis are proposed as new measures more closely related to the functional impairments. METHODS: Thirteen young healthy women volunteers had two applications per day on one arm of topical Clobetasol propionate 0.05% for 28 days, and they were followed for 28 days more. Skin modifications were studied by high-frequency ultrasound imaging, ultrasound RF signal analysis, optical coherence tomography and by the suction test. RESULTS: For all the techniques, a statistically significant change is observed with treatment. Large variations, around 30%, are observed for all techniques, but less for ultrasound imaging (10%). Dermis and epidermis thickness presented stable measurements on the nontreated zone. At the end of the study, measures returned to normal. The dynamic is mainly observed within the first 14 days of treatment and within the first 14 days after its cessation. CONCLUSION: Similar dynamics of skin modification during corticosteroid treatment was observed with very different techniques. Moreover, the potential of RF ultrasound analysis and mechanical skin measurement for characterizing skin structural and functional impairments has been evaluated.

Validation of a non-contact technique for local skin temperature measurements.

UNLABELLED: Here we propose to quantify local temperature variations using thermal imaging to assess the effect of dermatological lasers. OBJECTIVES: To quantify the temperature raise induced by laser application and to differentiate the effects of a potassium titanyl phosphate (KTP) laser and an intense pulsed light (IPL). METHODS: A randomized comparative study was performed on 10 adult volunteers with symmetrical rosacea treated by KTP laser or IPL. Skin temperature measurements were performed on inclusion, immediately after laser treatment and 3 min after thermal water application, using a high-resolution (0.08 degrees C) infrared thermal video camera. RESULTS: KTP laser treatment induced a significant rise in local skin temperature whereas no significant change was revealed by the IPL treatment. The infrared camera is a reliable and reproducible technique that allows a follow-up of skin temperature without skin contact. CONCLUSION: Thermography using an infrared camera could potentially be applied in clinical pharmacology for inflammatory reactions or scarring processes.

DNA copy number status is a powerful predictor of poor survival in endocrine pancreatic tumor patients.

The clinical behavior of endocrine pancreatic tumors (EPTs) is difficult to predict in the absence of metastases or invasion to adjacent organs. Several markers have been indicated as potential predictors of metastatic disease, such as tumor size > or =2 cm, Ki67 proliferative index > or =2%, cytokeratin (CK) 19 status, and recently in insulinomas, chromosomal instability (CIN). The goal of this study was to evaluate the value of these markers, and in particular of the CIN, to predict tumor recurrence or progression and tumor-specific death, using a series of 47 insulinomas and 24 non-insulinoma EPTs. From these EPT cases, a genomic profile has been generated and follow-up data have been obtained. The proliferative index has been determined in 68 tumors and a CK19 expression pattern in 50 tumors. Results are statistically analyzed using Kaplan-Meier plots and the log-rank statistic. General CIN, as well as specific chromosomal alterations such as 3p and 6q loss and 12q gain, turned out to be the most powerful indicators for poor tumor-free survival (P< or =0.0004) and tumor-specific death (P< or =0.0113) in insulinomas. The CIN, chromosome 7q gain, and a proliferative index > or =2% were reliable in predicting a poor tumor-free survival in non-insulinoma EPTs (P< or =0.0181, whereas CK19 expression was the most optimal predictor of tumor-specific death in these tumors. In conclusion, DNA copy number status is the most sensitive and efficient marker of adverse clinical outcome in insulinomas and of potential interest in non-insulinoma EPTs. As a consequence, this marker should be considered as a prognosticator to improve clinical diagnosis, most practically as a simple multi-target test.

Use of a 3-D imaging technique for non-invasive monitoring of the depth of experimentally induced wounds.

BACKGROUND/PURPOSE: Experimental studies of wound healing lack methods for standardized wounding and in situ depth assessment. Consequently, in this pilot study, an Erbium (Er):YAG laser has been used for wound induction with a non-invasive 3-D imaging technique as an alternative to histology. METHODS: Erbium:YAG ablation of human skin ex vivo was performed with total fluences of 10, 50 and 200 J/cm(2), removing the stratum corneum, epidermis/papillary dermis and deeper dermis, respectively. Wound depth was measured with the 3-D method and histologically. RESULTS: Wound depth was proportional to fluence for both techniques : 3-D, 17.7+/-1.7, 43.9+/-16 and 245.2+/-61 microm; histology, 14.6+/-1.7, 50.6+/-11.6 and 238+/-102 microm, respectively. CONCLUSIONS: The 3-D technique compares well with and is an improvement on histological measurement, providing true wound depth measurement, avoiding shape changes inherent with histology. Furthermore, the Er:YAG laser is a highly appropriate means of wound induction due to its rapidity and precision.

No mutations but an increased frequency of SDHx polymorphisms in patients with sporadic and familial medullary thyroid carcinoma.

Germline mutations of the three succinate dehydrogenase subunits SDHB, SDHC and SDHD have recently been associated with familial pheochromocytoma and paraganglioma. Several reasons make these genes candidate tumor suppressor genes for medullary thyroid carcinoma (MTC): (1) SDHB lies on chromosome 1p, the region known to be deleted most frequently in MTC, (2) MTCs develop from neural crest-derived cells, as do pheochromocytomas and paragangliomas and (3) patients with germline mutations of the Ret-protooncogene develop MTCs as well as pheochromocytomas, indicating a relationship of these tumors on a genetic level. Therefore, we attempted to determine whether the tumor suppressor genes SDHB, SDHC and SDHD are involved in sporadic and familial MTC. Somatic mutations of the SDH subunits were absent in all 35 investigated MTCs. Loss of heterozygosity was found in 27% (SDHB) and 4% (SDHD) respectively. While the frequency of non-coding, intronic polymorphisms did not differ in MTC patients compared with a control population, an accumulation of amino-acid coding polymorphisms (S163P in SDHB as well as G12S and H50R in SDHD) was found among MTC patients especially patients with familial tumors, suggesting a functional connection of coding SDH polymorphisms to activating Ret mutations.

[Subungueal exostosis of fingers in hereditary multiple exostosis. 3 cases]. / Exostoses sous-unguéales des doigts au cours de la maladie exostosante héréditaire. 3 observations.

INTRODUCTION: The multiple exostosis syndrome is a rare disease transmitted by autosomal dominant inheritance. Bone growth projecting outward from the long bones is observed in multiple localizations during growth. Prognosis of this benign disease is worsened by the possibility of chondrosarcoma. We report three cases of subungueal exostoses observed in children revealing hereditary exostosis. CASE REPORTS: Clinical examination evidenced progressive deformation of several fingers. In all three patients. There was subungueal tumefaction raising a fissured nail with longitudinal crests. In two cases there were also skeletal deformations. Radiograms showed multiple exostoses of the long bones in all three cases and in one a tumefaction of the scapula in addition to visualizing the subungueal exostoses. There was a family history of such manifestations in all cases. DISCUSSION: Subungueal exostosis is frequent in young adults, usually located in the large toe. These three observations were particularly interesting due to the subungueal localization during the first decade of life. Such localization are rare and usually concern several fingers.