Molecular effects of fractional ablative erbium:YAG laser treatment with multiple stacked pulses on standardized human three-dimensional organotypic skin models.

The molecular changes in gene expression following ablative laser treatment of skin lesions, such as atrophic scars and UV-damaged skin, are not completely understood. A standardized in vitro model of human skin, to study the effects of laser treatment on human skin, has been recently developed. Therefore, the aim of the investigation was to examine morphological and molecular changes caused by fractional ablative erbium:YAG laser treatment on an in vitro full-thickness 3D standardized organotypic model of human skin. A fractional ablative erbium:YAG laser was used to irradiate organotypic human 3D models. Laser treatments were performed at four different settings using a variety of stacked pulses with similar cumulative total energy fluence (60 J/cm2). Specimens were harvested at specified time points and real-time PCR (qRT-PCR) and microarray studies were performed. Frozen sections were examined histologically. Three days after erbium:YAG laser treatment, a significantly increased mRNA expression of matrix metalloproteinases and their inhibitors (MMP1, MMP2, MMP3, TIMP1, and TIMP2), chemokines (CXCL1, CXCL2, CXCL5, and CXCL6), and cytokines such as IL6, IL8, and IL24 could be detected. qRT-PCR studies confirmed the enhanced mRNA expression of IL6, IL8, IL24, CXCLs, and MMPs. In contrast, the mRNA expression of epidermal differentiation markers, such as keratin-associated protein 4, filaggrin, filaggrin 2, and loricrin, and antimicrobial peptides (S100A7A, S100A9, and S100A12) as well as CASP14, DSG2, IL18, and IL36ß was reduced. Four different settings with similar cumulative doses have been tested (N10%, C10%, E10%, and W25%). These laser treatments resulted in different morphological changes and effects on gene regulations. Longer pulse durations (1000 µs) especially had the strongest impact on gene expression and resulted in an upregulation of genes, such as collagen-1A2, collagen-5A2, and collagen-6A2, as well as FGF2. Histologically, all treatment settings resulted in a complete regeneration of the epidermis 3 days after irradiation. Fractional ablative erbium:YAG laser treatment with a pulse stacking technique resulted in histological alterations and shifts in the expression of various genes related to epidermal differentiation, inflammation, and dermal remodeling depending on the treatment setting applied. A standardized in vitro 3D model of human skin proved to be a useful tool for exploring the effects of various laser settings both on skin morphology and gene expression during wound healing. It provides novel data on the gene expression and microscopic architecture of the exposed skin. This may enhance our understanding of laser treatment at a molecular level.

Dexpanthenol modulates gene expression in skin wound healing in vivo.

Topical application of dexpanthenol is widely used in clinical practice for the improvement of wound healing. Previous in vitro experiments identified a stimulatory effect of pantothenate on migration, proliferation and gene regulation in cultured human dermal fibroblasts. To correlate these in vitro findings with the more complex in vivo situation of wound healing, a clinical trial was performed in which the dexpanthenol-induced gene expression profile in punch biopsies of previously injured and dexpanthenol-treated skin in comparison to placebo-treated skin was analyzed at the molecular level by Affymetrix® GeneChip analysis. Upregulation of IL-6, IL-1ß, CYP1B1, CXCL1, CCL18 and KAP 4-2 gene expression and downregulation of psorasin mRNA and protein expression were identified in samples treated topically with dexpanthenol. This in vivo study might provide new insight into the molecular mechanisms responsible for the effect of dexpanthenol in wound healing and shows strong correlations to previous in vitro data using cultured dermal fibroblasts.

Tacrolimus modulates dendritic cell activation in the sensitization phase of allergic contact dermatitis.

BACKGROUND: Knowledge of the effect of topically applied calcineurin antagonists such as tacrolimus on the sensitization phase of allergic contact dermatitis is currently limited. OBJECTIVE: To investigate tacrolimus-dependent immunomodulation on gene expression alterations in human antigen-presenting cells which are stimulated with small-molecular-weight contact allergens. METHODS: Monocyte-derived dendritic cells (moDC) and THP-1 cells were stimulated with the contact sensitizer cinnamic aldehyde (CAld) and compared with the very strong experimental sensitizer 2,4,6-trinitrobenzene sulfonic acid (TNBS) in vitro. Quantitative PCR analysis was used to detect gene expression changes, particularly of interleukin (IL) 8, as an indicator of differential dendritic cell (DC) gene expression after sensitizer stimulation in the absence or presence of tacrolimus and betamethasone at two different concentrations. RESULTS: DC activation was clearly demonstrated by a significant IL-8 upregulation after 24 h, whereas tacrolimus or betamethasone alone did not affect IL-8 baseline expression. Betamethasone and, to a lesser extent, tacrolimus led to a marked reduction of chemical-induced IL-8 expression by TNBS and CAld. CONCLUSION: The results of the present study support the hypothesis that the calcineurin inhibitor tacrolimus has modulatory effects on human antigen-presenting cells during the sensitization phase of allergic contact dermatitis. In addition, moDC as well as THP-1 cells may serve as a system to study immune-modulating effects of drugs such as glucocorticoids or calcineurin antagonists.

Current and future directions in the treatment of metastatic malignant melanoma.

Recently treatment strategies in advanced malignant melanoma have significantly changed. Due to high response rates (e.g. more than 50% for the Dartmouth-regimen), combination chemotherapy has been the standard therapy in several oncological and dermatooncological centers in the USA and Europe. For the last three years different prospective randomized phase III trials failed to achieve similar results. There was no benefit in overall survival and in response duration in comparison to single agent chemotherapy. Currently, randomized clinical trials seem to be the best approach for the clinical treatment of metastatic melanoma. In this review several novel strategies against malignant melanoma are discussed with focus on the role of single agent chemotherapy and biochemotherapy.

[Array technology in skin pharmacology and allergology]. / Arraytechnologien in der Dermatopharmazie und Allergologie.

Because of their variable application, microarrays are currently used in different areas of research and development, such as skin pharmacology and allergology. Microarrays are plane carriers, on whose surface a variety of known DNA-molecules and proteins were immobilised. Transcripts can be detected by cDNA- and oligonucleotid-arrays and proteins of activated genes can be discovered using antibody microarrays. Detection of allergen-specific IgE from human serum can be performed using allergen chips. Since many details of the molecular mechanism and pathogenesis of skin cancer and inflammatory skin diseases and the effect of xenobiotics on cells of the human skin are still not known, array-technologies are a powerful tool to identify novel marker genes and offer the possibility of develop new therapeutic strategies as well as prognosis- and diagnosis-systems.

Colonic cancer during pregnancy: case report and review of the literature.

Colonic cancer during pregnancy is rare. Herein we describe a case of adenocarcinoma of the transverse colon in a 29-year-old pregnant patient. Early diagnosis is difficult because the initial symptoms of colorectal cancer, such as abdominal pain, nausea and vomiting, constipation, and abdominal distention, are often attributed to a normal pregnancy. Management of colonic cancer during pregnancy depends on gestational age and operability of the tumor. Medical and surgical management considerations are discussed.

Presence of a sodium-translocating ATPase in membrane vesicles of the homoacetogenic bacterium Acetobacterium woodii.

Inverted membrane vesicles of the homoacetogenic bacterium Acetobacterium woodii catalyzed the hydrolysis of ATP with a rate of 100-150 nmol.min-1.mg protein-1. The ATPase was stimulated 1.4-1.6-fold by NaCl and inhibited by N,N'-dicyclohexylcarbodiimide tributyltin or azide. The degree of inhibition caused by F0-directed but not F1-directed inhibitors was affected by the Na+ concentration in the medium. These experiments indicated the presence of a sodium-translocating ATPase. This was verified by transport studies. Upon addition of ATP to inverted vesicles, 22Na+ was actively transported into the intravesicular space up to a 24-fold accumulation. Na+ transport was inhibited by the sodium ionophore N,N,N',N',-tetracyclohexyl-1,2-phenyl-enedioxydiacetamide but stimulated by valinomycin with potassium whereas the protonophore 3,5,-di-tert-butyl-4-hydroxybenzylidenemalonitrile was without effect. N,N'-dicyclohexylcarbodiimide and tributyltin inhibited 22Na+ transport. These experiments are in accordance with a primary electrogenic Na+ transport as catalyzed by a F1F0-ATPase.

A sodium-stimulated ATP synthase in the acetogenic bacterium Acetobacterium woodii.

Experiments with resting cells of Acetobacterium woodii were performed to elucidate the coupling ion used by the ATP synthase. A. woodii synthesized ATP in response to an artificial delta pH, indicating the presence of a proton-translocating ATPase. On the other hand, a delta pNa, as well as a proton diffusion potential, could serve as a driving force for ATP synthesis with the latter strictly dependent on Na+. These results are indicative for the presence of a Na(+)-translocating ATP synthase in A. woodii.

Hodgkin's disease in children: correlation of clinical characteristics, staging procedures, and treatment at the University of Minnesota.

The cases of 63 children treated for Hodgkin's disease were retrospectively evaluated according to clinical and laboratory characteristics at initial appearance, clinical and pathologic staging, and treatment for their effects on survival and disease-free survival. An initial erythrocyte sedimentation rate over 50 mm/h was common in patients who ultimately had a relapse. There was no correlation between the size of the mediastinal mass at diagnosis and occurrence of relapse. A residual mediastinal mass was found in 22% of patients after 1 year of treatment regardless of its size at initial appearance. With a median follow-up time of 10.5 years, the overall survival rate is 89%, and disease-free survival rate is 71%. The disease-free survival rates for patients with stages I-IV disease are 92, 81, 78, and 40%, respectively. Relapses occurred in 7 of 22 (36%) patients with positive staging laparotomy despite radiotherapy for three with stage IA and IIA disease, chemotherapy alone for two with stage IIIB disease, or chemotherapy for one with stage IIIB and one with stage IVB disease. Of patients who had no evidence of abdominal Hodgkin's disease at a staging laparotomy, 6 of 34 (19%) had a relapse. These included one with stage IA and five stage IIA disease, all treated with radiotherapy alone. Treatment of stage III and IV disease with regimens including CCNU (lomustine) or cyclophosphamide, plus vinblastine sulfate or vincristine sulfate, prednisone, and procarbazine hydrochloride with or without radiation therapy yielded poor results, with 6/7 having a relapse.