ABSTRACT
Actinic keratosis, a frequent carcinoma in situ of non-melanoma skin cancer (NMSC), can transform into life-threatening cutaneous squamous cell carcinoma. Current treatment is limited due to low complete clearance rates and asks for novel therapeutic concepts; the novel purine nucleotide analogue OxBu may be an option. In order to enhance skin penetration, solid lipid nanoparticles (SLN, 136-156 nm) were produced with an OxBu entrapment efficiency of 96.5 ± 0.1%. For improved preclinical evaluation, we combined tissue engineering with clinically used keratin-18 quantification. Three doses of 10(-3) mol/l OxBu, dissolved in phosphate-buffered saline as well as loaded to SLN, were effective on reconstructed NMSC. Tumour response and apoptosis induction were evaluated by an increase in caspase-cleaved fragment of keratin-18, caspase-7 activation as well as by reduced expression of matrix metallopeptidase-2 and Ki-67. OxBu efficacy was superior to equimolar 5-fluorouracil solution, and thus the drug should be subjected to the next step in preclinical evaluation.
Subject(s)
Drug Delivery Systems , Guanosine/analogs & derivatives , Organophosphonates/administration & dosage , Skin Neoplasms/drug therapy , Administration, Topical , Animals , Humans , Nanoparticles/administration & dosage , Tissue EngineeringABSTRACT
BACKGROUND: The clinical diagnosis of amelanotic melanoma is often challenging, because the classical clinical and dermoscopic features of pigmented melanoma are usually missing. The reflectance confocal microscopy (RCM) offers an additional possibility of an in vivo diagnosis of both pigmented and amelanotic melanoma lesions. OBJECTIVES: To test the value of RCM in vivo in the preoperative prediction of melanoma lesions lacking significant pigment and to compare the results with the evaluation by dermoscopy and histopathology. METHODS: We examined seven patients with the clinically uncertain differential diagnosis of partially or completely amelanotic melanoma by RCM and dermoscopy prior to surgical excision of the lesions according to the previously suggested dermoscopy algorithm and RCM score for melanoma. The following RCM features were evaluated: major criteria scored +2 (non-edged papillae, cytological atypia at the dermo-epidermal junction) and minor criteria +1 (roundish pagetoid cells, widespread pagetoid infiltration, nucleated cells within dermal papillae, cerebriform cell clusters). The dermoscopic evaluation included the following criteria: polymorphous vessels, dotted and linear irregular vessels, hairpin vessels, pink-erythematous colour, milky red areas, irregularly shaped depigmentation, blue-grey dots and subtle pigmentation. RESULTS: The preoperative in vivo RCM analysis revealed common features of melanoma also found in pigmented melanoma lesions. All lesions showed a score above three in the applied RCM algorithm which was proposed earlier as the threshold for malignancy. In dermoscopy, five of seven lesions showed characteristic vascular changes. CONCLUSION: In vivo RCM is a valuable tool in the preoperative diagnosis of partially and completely amelanotic tumours suspicious for melanoma in addition to dermoscopic evaluation.
Subject(s)
Melanoma/pathology , Skin Neoplasms/pathology , Skin Neoplasms/surgery , Dermatologic Surgical Procedures/methods , Dermoscopy/methods , Diagnosis, Differential , Female , Germany , Humans , Male , Melanoma/diagnosis , Melanoma/surgery , Melanoma, Amelanotic/diagnosis , Melanoma, Amelanotic/pathology , Melanoma, Amelanotic/surgery , Microscopy, Confocal , Neoplasm Invasiveness/pathology , Neoplasm Staging , Preoperative Care/methods , Risk Assessment , Sampling Studies , Skin Neoplasms/diagnosis , Treatment OutcomeABSTRACT
BACKGROUND: Topical preparations are a common treatment for superficial acute wounds, which at the least do not interfere with healing and ideally result in enhanced wound healing irrespective of microbial colonization. OBJECTIVE: To examine the effects of a topical antimicrobial gel and its vehicle on the wound healing of standardized, superficial abrasions. METHODS: Thirty-three healthy volunteers were enrolled in a double-blinded, randomized, intraindividual comparison study. Three standardized, superficial abrasions were induced on their forearms. A tyrothricin 0.1% gel (Tyrosur® gel; Engelhard Arzneimittel GmbH & Co. KG, Niederdorfelden, Germany) and its vehicle were randomly applied to two of the test areas, and one lesion remained untreated. RESULTS: A significant improvement of wound healing was seen with both tyrothricin 0.1% gel and its corresponding vehicle in the clinical assessment. The mean area under the curve (AUC) of wound healing scores was the same for both preparations and the mean reepithelization scores were comparable at all test points over the entire 12 days. A lower mean AUC representing less reepithelization was found for the untreated test fields. CONCLUSION: The use of tyrothricin 0.1% gel and its corresponding vehicle resulted in statistically significant improved wound healing with an earlier onset of healing in particular. Based on these results obtained using an abrasive wound model, it can be concluded that the addition of tyrothricin 0.1% to the gel vehicle did not interfere with the improved wound healing seen with the vehicle alone.
Subject(s)
Anti-Bacterial Agents/administration & dosage , Anti-Infective Agents, Local/administration & dosage , Skin/drug effects , Tyrothricin/administration & dosage , Wound Healing/drug effects , Adult , Double-Blind Method , Female , Gels , Humans , Male , Middle Aged , Skin/injuries , Treatment Outcome , Young AdultABSTRACT
BACKGROUND: Terbinafine nail solution (TNS) was developed for the treatment of onychomycosis. OBJECTIVE: To assess the efficacy of TNS vs. vehicle and amorolfine 5% nail lacquer. METHODS: Subjects with mild-to-moderate toe onychomycosis (25% to ≤75% nail-involvement, matrix uninvolved) were randomized to receive either TNS or vehicle in two double-blind studies, and to TNS or amorolfine in an active-controlled, open-label study. Primary endpoint was complete cure (no residual clinical involvement and negative mycology) at week 52. Secondary endpoints were mycological cure (negative mycology defined as negative KOH microscopy and negative culture) and clinical effectiveness (≤10% residual-involvement and negative mycology) at week 52. RESULTS: Complete cure was not different between TNS vs. vehicle and amorolfine. Mycological cure was higher with TNS vs. vehicle, as was clinical effectiveness with TNS vs. vehicle, and TNS and amorolfine were not different for secondary efficacy endpoints. Patients achieving mycological cure had a better clinical outcome, and efficacy was improved in subjects with milder disease. Post hoc analysis suggests that nail thickness is an important prognostic factor. Moreover, mycological cure may require 6 months of treatment regimen while complete cure and clinical effectiveness may be achievable only after 10 months. A simulation study suggests that longer treatment duration would have resulted in higher complete cure with TNS vs. vehicle. Study treatments were well-tolerated. CONCLUSION: Primary efficacy objectives were not met in the studies reported herein. Possible reasons for failure to achieve significant outcomes include insufficient length of treatment; stringency of primary endpoint and severity of nail involvement of study population.
Subject(s)
Antifungal Agents/therapeutic use , Nail Diseases/drug therapy , Naphthalenes/therapeutic use , Onychomycosis/drug therapy , Administration, Topical , Adolescent , Adult , Aged , Antifungal Agents/administration & dosage , Antifungal Agents/adverse effects , Child , Double-Blind Method , Female , Humans , Male , Middle Aged , Naphthalenes/administration & dosage , Naphthalenes/adverse effects , Randomized Controlled Trials as Topic , Terbinafine , Young AdultABSTRACT
Antimicrobial peptides (AMPs) are small, cationic, amphiphilic peptides with broad-spectrum microbicidal activity against both bacteria and fungi. In mammals, AMPs form the first line of host defense against infections and generally play an important role as effector agents of the innate immune system. The AMP era was born more than 6 decades ago when the first cationic cyclic peptide antibiotics, namely polymyxins and tyrothricin, found their way into clinical use. Due to the good clinical experience in the treatment of, for example, infections of mucus membranes as well as the subsequent understanding of mode of action, AMPs are now considered for treatment of inflammatory skin diseases and for improving healing of infected wounds. Based on the preclinical findings, including pathobiochemistry and molecular medicine, targeted therapy strategies are developed and first results indicate that AMPs influence processes of diseased skin. Importantly, in contrast to other antibiotics, AMPs do not seem to propagate the development of antibiotic-resistant micro-organisms. Therefore, AMPs should be tested in clinical trials for their efficacy and tolerability in inflammatory skin diseases and chronic wounds. Apart from possible fields of application, these peptides appear suited as an example of the paradigm of translational medicine for skin diseases which is today seen as a 'two-way road' - from bench to bedside and backwards from bedside to bench.
Subject(s)
Antimicrobial Cationic Peptides/pharmacology , Skin Diseases/drug therapy , Skin/drug effects , Animals , Antimicrobial Cationic Peptides/therapeutic use , Humans , Molecular Medicine/methods , Translational Research, Biomedical/methodsABSTRACT
Mometasone furoate, a potent glucocorticoid (class III) with a favorable benefit/risk ratio, has emerged as a standard medication for the treatment of inflammatory skin disorders. The purpose of the investigation presented here was to determine the noninferiority of a topical mometasone formulation, a light cream (O/W 60/40 emulsion) with mometasone furoate 0.1% (water content of 33%) versus marketed comparators. Using the vasoconstrictor assay, a strong blanching effect of the new cream (called Mometasone cream) comparable to that of a mometasone comparator, a fatty cream with mometasone furoate 0.1%, could be demonstrated. Thus, the topical bioavailability of the active ingredient mometasone furoate (0.1%) was regarded to be similar for Mometasone cream and the mometasone comparator. Using the psoriasis plaque test, a strong antipsoriatic effect comparable to that of the mometasone comparator was found for Mometasone cream after 12 days of occlusive treatment. A nearly identical reduction in the mean infiltrate thickness and similar mean AUC values were noted with both formulations confirmed by clinical assessment data. The noninferiority of Mometasone cream to its active comparator with respect to the AUC of change to baseline in infiltrate thickness was demonstrated. Both medications were well tolerated. Overall, Mometasone cream and the mometasone comparator showed similar efficacy and tolerability. Mometasone cream, in addition to its high potency and good tolerability, provides the properties of a light cream, which might make this new medication particularly suitable for application on acutely inflamed and sensitive skin.
Subject(s)
Dermatologic Agents/pharmacokinetics , Glucocorticoids/pharmacokinetics , Pregnadienediols/pharmacokinetics , Psoriasis/drug therapy , Skin Absorption , Skin/drug effects , Skin/metabolism , Administration, Cutaneous , Adolescent , Adult , Aged , Area Under Curve , Biological Availability , Chemistry, Pharmaceutical , Dermatologic Agents/administration & dosage , Dermatologic Agents/adverse effects , Dermatologic Agents/chemistry , Double-Blind Method , Female , Germany , Glucocorticoids/administration & dosage , Glucocorticoids/adverse effects , Glucocorticoids/chemistry , Humans , Male , Middle Aged , Mometasone Furoate , Ointments , Pregnadienediols/administration & dosage , Pregnadienediols/adverse effects , Pregnadienediols/chemistry , Psoriasis/pathology , Skin/blood supply , Skin/pathology , Vasoconstriction/drug effects , Young AdultABSTRACT
BACKGROUND: While the serological tumour marker S100 is well established for the detection of metastatic melanoma, the extracellular matrix protein osteopontin (OPN) seems to be a promising novel marker for invasive melanoma. OBJECTIVES: We analysed the potential of OPN as a serological tumour marker for metastatic melanoma and evaluated its combination with S100 and lactate dehydrogenase (LDH) levels to increase the reliability of these biomarkers for the detection of metastatic disease. METHODS: We examined OPN in the peripheral blood of 110 melanoma patients using enzyme-linked immunosorbent assay and combined it with S100 and LDH levels. In addition, the protein expression of OPN was analysed in tissue sections of melanocytic nevi and melanomas of different progression stages by immunohistochemistry. RESULTS: The independent comparison of S100 and OPN levels in metastatic vs. non-metastatic patients revealed a P-value <0.001 respectively. The predictiveness of OPN, S100 and LDH was 0.85, 0.89 and 0.69 as measured by the area under the receiver operating curve (AUC) respectively, while the combination of the two biomarkers OPN and S100 showed an AUC of 0.97. The optimal cut-off of the combination of OPN and S100 yielded a specificity of 85.9% and a sensitivity of 95.5%. By immunohistochemistry, OPN protein expression was detected in 29% (7/24) of melanocytic nevi, 67% (30/45) of primary melanomas and 39% (7/18) of metastatic melanomas. CONCLUSIONS: Together, OPN seems to be a promising novel biomarker for the detection of metastatic disease in melanoma patients, showing elevated plasma levels in metastatic disease and increased protein expression in melanocytic lesions. The combination of OPN with the well-established tumour marker S100 might increase the prediction of metastases.
Subject(s)
Melanoma/blood , Osteopontin/blood , Skin Neoplasms/blood , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunohistochemistry , L-Lactate Dehydrogenase/blood , Male , Middle Aged , S100 Proteins/bloodABSTRACT
Fluticasone propionate (FP), a medium potent glucocorticoid (class III) of carbothioate nature with a favourable benefit/risk ratio, has emerged as a standard medication for the topical treatment of inflammatory skin disorders, in particular atopic dermatitis (AD). FP is available as a 0.05% cream and a 0.005% ointment formulation. The glucocorticoid is characterized by high lipophilicity, high affinity binding to the glucocorticoid receptor and a rapid hepatic biotransformation. Though skin blanching following topical application of FP surpasses that given with glucocorticoids of medium strength, clinical trials show a low potential of FP for local and systemic adverse effects. Even in paediatric patients with AD as well as in difficult-to-treat areas like face, eyelids and intertriginous areas, FP proved to be both effective and safe. Thus, the therapeutic effects of FP clearly outweigh the unwanted effects. Correspondingly, a therapeutic index of 2.0 can be attributed to this glucocorticoid. In this respect, topical FP does not differ from other topical glucocorticoids with increased benefit-to-risk ratio, e.g. prednicarbate, methylprednisolone aceponate and mometasone furoate. However, randomized controlled trials do not only support conventional intervention but also innovative maintenance treatment.
Subject(s)
Androstadienes/therapeutic use , Dermatitis, Atopic/drug therapy , Dermatologic Agents/therapeutic use , Administration, Topical , Androstadienes/administration & dosage , Androstadienes/adverse effects , Dermatologic Agents/administration & dosage , Dermatologic Agents/adverse effects , Fluticasone , HumansABSTRACT
Rosacea is like no other disease a problem for patients regarding the use of skin care and cleaning products. The subjective assessment of the severity of the illness is an important factor regarding the development of depression in these patients. Inadequate skin care and cleaning products can lead to irritation and stinging of the skin. Dermatologists should address questions regarding skin care, cleaning and sun screens. Because of the higher irritability of the skin of rosacea patients, all possibly irritating cleaning products or procedures should be avoided. The water temperature is also important; it should be lukewarm to avoid the provocation of a vascular reaction. Soaps should be avoided, because they are alkaline and thus lead to a higher pH of the skin. A higher pH of the skin can lead to irritation. Appropriate make-up causes no aggravation of the skin and increases patient's satisfaction with their skin and thus leads to a higher compliance with pharmacological therapy. Laser or intense pulsed light treatment can improve telangiectasia or erythema. Operative treatment of rhinophyma is effective and well-established.
Subject(s)
Laser Therapy/methods , Rosacea/prevention & control , Soaps/therapeutic use , Humans , Rhinophyma , Rosacea/drug therapy , Soaps/adverse effectsABSTRACT
BACKGROUND: Due to its strong water binding potential, hyaluronic acid (HA) is a well-known active ingredient for cosmetic applications. However, based on its varying molecular size, skin penetration of HA may be limited. Recent studies have demonstrated that low-molecular-weight HA (LMW HA) may show a certain proinflammatory activity. We thus aimed to characterize an LMW-sized HA molecule that combines strong anti-aging abilities with efficient skin penetration but lacks potential proinflammatory effects. METHODS: Total RNA and total protein were isolated from reconstituted human epidermis following incubation with HAs of various molecular weights (20, 50, 130, 300, 800 and 1,500 kDa). Tumor necrosis factor-α expression was determined using quantitative PCR. Genomic and proteomic expression of various junctional proteins was determined using Affymetrix and common Western blotting techniques. RESULTS: LMWHA of approximately 50 kDa did not significantly alter tumor necrosis factor-α expression compared to 20-kDa HA, but revealed significantly higher skin penetration rates than larger sized HA associated with increased expression of genes and proteins known to be involved in tight junction formation and keratinocyte cohesion. CONCLUSION: LMW HA of approximately 50 kDa shows better penetration abilities than larger-sized HA. In addition, LMW HA influences the expression of various genes including those contributing to keratinocyte differentiation and formation of intercellular tight junction complexes without showing proinflammatory activity. These observations contribute to current knowledge on the effects of LMW HA on keratinocyte biology and cutaneous physiology.
Subject(s)
Hyaluronic Acid/pharmacology , Skin/drug effects , Tumor Necrosis Factor-alpha/biosynthesis , Cell Differentiation/drug effects , Cells, Cultured , Epidermis/drug effects , Epidermis/metabolism , Gene Expression Regulation/drug effects , Humans , Hyaluronic Acid/chemistry , Keratinocytes/drug effects , Keratinocytes/metabolism , Molecular Weight , Skin/cytology , Skin/metabolism , Skin Physiological Phenomena/drug effects , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism , Up-Regulation/drug effectsABSTRACT
The aim of this study was to evaluate different urea-containing cosmetic preparations designed for foot care regarding skin occlusion. The primary aim was therefore to screen the short-term transepidermal water loss (TEWL) as a parameter for skin barrier function and skin occlusion and to characterize the relative role of the vehicle, i.e. cream or foam in the context of cosmetics containing urea in the 2-10% range addressing the cosmetic products urea 2% cream (GEHWOL FUSSKRAFT blau), petrolatum containing cream (GEHWOL med Schrundensalbe), urea 10% cream (GEHWOL med Lipidro-Crème), urea 10% foam (Allpresan Fuss Schaum) and vaseline (positive control) compared with an untreated area on the volar forearms of volunteers. Moreover, the short time (24 h) kinetics regarding the moisturizing effect of cream and foam formulations in diabetic patients were compared. The efficacy of a cream on reduction of skin thickness of hyperkeratotic skin in the heel region before and after a period of product application was also evaluated. In some of the trials, healthy individuals and in others, diabetic patients (type I and II) were enrolled. TEWL was determined before product application, as well as at given points of time thereafter. In this study, no excessive occlusion effects comparable with a blockage of the skin's natural water evaporation could be observed for any of the test products. To the extent to be expected, this was found neither for the cream products nor for the foam product. Slightly lowered TEWL values after application of the 10% urea cream can be interpreted as a beneficial effect in terms of an improved barrier function. Regarding skin moisture, the urea-containing cream formulation appeared equal or slightly superior to the foam formulation. The thickness of the horny layer was found reduced after application of 10 % urea-containing cream. At present it looks as if cream vehicles would still be vehicles of choice in general, when it comes to the formulation of skin care preparations for not only dry skin but also in the context of pedal skin care.
Subject(s)
Dermatologic Agents/administration & dosage , Foot , Urea/administration & dosage , Female , Humans , Middle Aged , Pharmaceutical VehiclesABSTRACT
Moist wound care has been established as standard therapy for chronic wounds with impaired healing. Healing in acute wounds, in particular in minor superficial acute wounds - which indeed are much more numerous than chronic wounds - is often taken for granted because it is assumed that in those wounds normal phases of wound healing should run per se without any problems. But minor wounds such as small cuts, scraps or abrasions also need proper care to prevent complications, in particular infections. Local wound care with minor wounds consists of thorough cleansing with potable tap water or normal saline followed by the application of an appropriate dressing corresponding to the principles of moist wound treatment. In the treatment of smaller superficial wounds, it appears advisable to limit the choice of dressing to just a few products that fulfil the principles of moist wound management and are easy to use. Hydroactive colloid gels combining the attributes of hydrocolloids and hydrogels thus being appropriate for dry and exuding wounds appear especially suitable for this purpose - although there is still a lack of data from systematic studies on the effectiveness of these preparations.
Subject(s)
Skin/injuries , Wound Healing/physiology , Wounds and Injuries/therapy , Bandages , Cicatrix/prevention & control , Colloids , Humans , Hydrogels , Wounds and Injuries/physiopathologyABSTRACT
The present in vivo investigation using a total of 30 healthy adult volunteers with Fitzpatrick skin type II examines the persistent efficacy of sunscreens using liposomal suspensions as the vehicle. Based on the COLIPA guidelines, the protective effect of a single application of 4 different liposomal sunscreen formulations (sun protection factors, SPFs: 50+, 30, 25 and 15) against sunburn at the recommended amount of 2 mg/cm(2) was determined after exposure of the skin to plain water and salt water and after profuse perspiration. Under the influence of plain water, salt water and sweating, the SPF values of sunscreen 1 (labeled SPF of 50+) were reduced only marginally to 97, 96 and 99%, respectively, those of sunscreen 2 (labeled SPF of 30) to 97, 96 and 99%, respectively, those of sunscreen 3 (labeled SPF of 25) to 90, 83 and 91%, respectively, and those of sunscreen 4 (labeled SPF of 15) to 96, 96 and 95%, respectively. This set of data shows that despite plain water and salt water immersion or profuse sweating, the liposomal sunscreen formulation may deliver a long-lasting protective effect in everyday situations encountered by outdoor workers or during leisure activities.
Subject(s)
Sodium Chloride , Sunscreening Agents/chemistry , Sweat , Water , Administration, Cutaneous , Adult , Female , Humans , Liposomes , Male , Middle AgedABSTRACT
To learn about the interaction between drug agents and nanoparticular carrier systems, the physical analytical methods of parelectric, electron spin and fluorescence spectroscopy have proven helpful tools to yield descriptive models of such complex systems. For a deeper understanding of drug absorption from body surfaces and drug distribution into the tissues, however, the lack of knowledge about the interaction between such agents and membranes on different levels is a severe drawback. This gap can be closed by the application of atomic force microscopy at normal temperatures and under the admission of liquid surroundings. Moreover, this method allows the inspection of such system-membrane interactions in dependence on time. We studied membrane topography in liquid and gel-phase mixtures, structural changes of membranes during their destruction by aqueous peptide solutions as well as the stability of the membranes exposed to surfactants of increasing concentration and to lipid nanoparticles (solid lipid nanoparticles, nanostructured lipid carriers). For future modelling we can describe the geometry of lipid nanoparticles as well.
Subject(s)
Drug Carriers/chemistry , Humidity , Indicators and Reagents , Lipids/chemistry , Membranes, Artificial , Microscopy, Atomic Force , Peptides/chemistry , Spectrometry, Fluorescence , Surface-Active AgentsABSTRACT
BACKGROUND: Reports on controlled trials on the efficacy and tolerability of sulfonated shale oils in atopic eczema are not available so far. The aim of this study was to investigate whether topically applied, specially prepared pale sulfonated shale oil (PSSO) cream is capable of improving symptoms/signs of mild to moderate atopic eczema in children more efficaciously than a corresponding vehicle cream. PATIENTS AND METHODS: A total of 99 children suffering from mild to moderate atopic eczema were enrolled in this multicentre, randomized, vehicle-controlled study. Verum or vehicle cream was applied to the affected skin area three times a day over 4 weeks. As the primary outcome parameter served the reduction of the total score after 4 weeks of treatment, compared with the initial examination. Secondary outcome parameters were addressed as well. Tolerability was judged by investigators and patients/parents, and adverse events were documented. RESULTS: After 4 weeks of treatment, the total score declined from 13.4 ± 3.7 to 4.5 ± 7.4 score points in the verum group and from 13.0 ± 3.1 to 11.7 ± 8.6 score points in the vehicle group (P < 0.0001). The superiority of verum regarding total score was already apparent after a treatment period of 1 week (reduction by 5.6 ± 4.3 vs. 1.3 ± 5.9 score points; P < 0.0001). Tolerability was found superior at the end of the treatment in the verum when compared with the control group--both by investigators (P < 0.0001) and patients/parents (P = 0.0051). CONCLUSION: Pale sulfonated shale oil cream 4% is capable to treat mild to moderate atopic eczema in children more efficaciously than vehicle and is well tolerated. PSSO thus represents a valuable addition to our therapeutic armamentarium. PSSO should be considered in particular when valid alternatives for topical glucocorticoids are sought for.
Subject(s)
Dermatitis, Atopic/drug therapy , Dermatologic Agents/therapeutic use , Emollients/therapeutic use , Quaternary Ammonium Compounds/therapeutic use , Administration, Topical , Child , Child, Preschool , Dermatologic Agents/administration & dosage , Dermatologic Agents/adverse effects , Dose-Response Relationship, Drug , Drug Tolerance , Emollients/administration & dosage , Emollients/adverse effects , Female , Humans , Infant , Male , Quaternary Ammonium Compounds/administration & dosage , Quaternary Ammonium Compounds/adverse effects , Severity of Illness Index , Treatment OutcomeABSTRACT
Actinic keratosis and cutaneous squamous cell carcinoma are of increasing importance with aging and increased ultraviolet light exposure in Western societies. Efficient and well-tolerated therapy is still a matter of concern. As with tumours of other organs, new target sites and innovative drugs selectively addressing them are widely looked for. Due to the relevance for DNA synthesis and thus cell proliferation, human DNA polymerase alpha should be such a target, the more so as the three-dimensional structure of the active site has been proposed based on the application of molecular modelling methods and molecular dynamics simulations. The modelled structure of the active site was used for docking nucleotide analogues in order to design selective inhibitors. Consequently, well-fitting thymidine and guanosine analogues were synthesized and tested in vitro for their influence on normal and transformed human keratinocytes. In fact, the combination of modelling studies and in vitro tests allowed us to design antiproliferative and cytotoxic agents which are new drug candidates for the therapy of skin tumours, given the agents are no relevant substrates of nucleotide transporters (MRP-4, MRP-5) expressed by skin cancer cells. Essential kinases for nucleoside activation were detected, too, corresponding with the observed effects of nucleoside analogues. Due to the rather high molecular weight and poor solubility, however, skin penetration should be poor and thus topical therapy may require carriers to improve the uptake. This becomes feasible by lipidic and non-lipidic nanoparticles which can enhance the uptake of lipophilic agents up to 13-fold.
Subject(s)
Carcinoma, Squamous Cell/drug therapy , Keratosis, Actinic/drug therapy , Skin Neoplasms/drug therapy , Administration, Cutaneous , Aging , Animals , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/therapeutic use , Carcinoma, Squamous Cell/pathology , Cell Proliferation/drug effects , Drug Delivery Systems , Drug Design , Humans , Keratosis, Actinic/physiopathology , Models, Molecular , Nanoparticles , Skin Absorption , Skin Neoplasms/pathologyABSTRACT
The medical treatment of acne is generally sufficient to meet the expectations of acne patients. However, in a number of situations additional therapeutic approaches may be advisable. There are a wide variety of useful physical methods. They range from electromagnetic waves, usually light, to peeling and manual therapy. Phototherapy of acne includes not just visible light but also laser and flash lamp therapy. The present review provides an overview on the evidence. Visible light, in particular blue light, provides an effective option for treatment of inflammatory acne. Photodynamic therapy also is efficacious; however, it should not be used because of an unfavorable risk-benefit ratio. UV treatment of acne is obsolete. Newer studies on the use of a variety of laser systems and flash lamps have demonstrated in part rewarding results.
Subject(s)
Acne Vulgaris/therapy , Chemexfoliation/methods , Cosmetic Techniques , Low-Level Light Therapy/methods , Photochemotherapy/methods , Humans , Treatment OutcomeABSTRACT
Appropriate cosmetics for skin cleansing are capable of contributing to a reduction of especially inflammatory lesions in acne-prone patients and to support pharmacological intervention in patients with manifest acne. Cleansing of acne-prone skin should employ acidified synthetic cleansers with a pH of 5.5 rather than soap. Furthermore, the ingredients of certain skin care products, i.e. nicotinamide, lactic acid, triethyl acetate/ethyllineolate, and prebiotic plant extracts, affect different mechanisms of acne pathogenesis and therefore may contribute to a decrease in acne lesions. At least some of these ingredients underscore the concept of evidence-based cosmetics. In contrast, the problem of acne lesions caused by comedogenic ingredients in cosmetics today is negligible.
Subject(s)
Acne Vulgaris/drug therapy , Cosmetics/administration & dosage , Dermatitis/drug therapy , Dermatologic Agents/administration & dosage , Skin/drug effects , Acne Vulgaris/complications , Dermatitis/complications , HumansABSTRACT
In recent years many efforts have been made to replace dermal toxicity testing of chemicals in the animal by in vitro assays. As a member of a German research consortium, we have previously contributed to the validation of an in vitro test protocol for percutaneous absorption studies on the basis of reconstructed human epidermis and both human and pig skin ex vivo. Aiming to assess the barrier properties of a newly developed reconstructed skin model, this protocol has now been transferred to the Phenion Full-Thickness Skin Model (FT model). The permeation of testosterone and caffeine was quantified in parallel to that of pig skin using Franz-type diffusion cells. In addition, the permeation of benzoic acid and nicotine was studied. As expected, the FT model is more permeable than pig skin, yet its barrier properties are well in accordance with those of reconstructed human epidermis when compared to previous data. In fact, the FT model most efficiently retards testosterone as the compound of highest lipophilicity, which can be explained by an additional uptake by a reservoir formed by the dermis equivalent. Thus, the structure closely parallels human skin. In consequence, the Phenion FT model appears to be suitable for percutaneous absorption studies in hazard analysis and should be subjected to a catch-up validation study.