bluuebunny/crossref_metadata_2025 huggingface dataset:
Epstein-Barr Virus WZhet DNA Can Induce Lytic Replication in Epithelial Cells in vitro, although WZhet Is Not Detectable in Many Human Tissues in vivo
Authors: Ryan Julie L. , Jones Richard J. , Elmore Sandra H. , Kenney Shannon C. , Miller George , Schroeder Jane C. , Gulley Margaret L.
Published: April 2009

Objective:WZhet is a rearranged and partially deleted form of the Epstein-Barr virus (EBV) genome in which the BamH1W region becomes juxtaposed with and activates BZLF1, resulting in constitutive viral replication. We tested whether WZhet induces viral replication in epithelial cells, and we studied its prevalence in a wide range of lesional tissues arising in vivo. Methods: A quantitative real-time PCR assay targeting EBV WZhet DNA was developed to measure this recombinant form of the EBV genome. Results:WZhet DNA was undetectable in any of 324 plasma or paraffin-embedded tissue samples from patients with EBV-associated and EBV-negative disorders. These included specimens from patients with Hodgkin or non-Hodgkin lymphoma, post-transplant lymphoproliferation, nasopharyngeal or gastric adenocarcinoma, and infectious mononucleosis. However, WZhet DNA was detected in vitro in EBV-infected AGS gastric cancer cells. Additionally, transient transfection of infected AGS gastric cancer cells showed that viral replication could be induced by a WZhet plasmid. Conclusion: This is the first evidence that WZhet induces the EBV lytic cycle in an epithelial cell line. Our negative findings in natural settings suggest that WZhet is a defective viral product that thrives in the absence of a host immune system but is rarely present in vivo.
Prevalence of Hepatitis B Virus Subgenotypes and Basal Core Promoter, Precore Variants in Patients with Acute Hepatitis B in Central Vietnam
Authors: Hayashi Kazuhiko , Katano Yoshiaki , Chuong Tran Xuan , Takeda Yasushi , Ishigami Masatoshi , Itoh Akihiro , Hirooka Yoshiki , Nakano Isao , Huy Tran Van , Minh Nguyen Ngoc , Diem Tran thi Minh , An Dong thi Hoai , Phiet Pham Hoang , Goto Hidemi
Published: April 2009

Objective: Hepatitis B virus (HBV) has been classified into 8 genotypes that have different geographic distributions. The clinical outcomes of acute hepatitis are dependent on genotype. The aim of this study was to investigate the distribution of HBV subgenotypes and basal core promoter (BCP)/precore (PC) regions in acute hepatitis patients in Central Vietnam to clarify the distributions and the clinical and virological differences. Methods: 27 patients with acute hepatitis B were studied. HBV subgenotypes and BCP/PC variants were determined by direct sequencing of the preS, BCP/PC regions, respectively. Results: HBV subgenotypes B4/Ba (n = 22) and C1/Cs (n = 5) were detected. Of the 27 patients, 3 developed fulminant hepatic failure, and all were infected with B4/Ba. Three patients had a BCP mutation, and 10 patients had a PC mutation in subgenotype B4/Ba. Three patients with C1/Cs had a BCP mutation. Two of 3 patients who progressed to fulminant hepatic failure had T1762, A1764, and A1896 simultaneously. None of the patients with acute, self-limited hepatitis carried these triple mutations. Conclusion: The prevalent HBV subgenotypes in patients with acute hepatitis B in Central Vietnam were B4/Ba and C1/Cs. BCP/PC variants have an association with the development of fulminant hepatic failure in subgenotype B4/Ba.
Dithranol: A Review of the Mechanism of Action in the Treatment of Psoriasis vulgaris
Authors: Kemény Lajos , Ruzicka Thomas , Braun-Falco Otto
Published: April 2009

Dithranol is highly effective in the treatment of psoriasis. The drug inhibits keratinocyte hyperproliferation, granulocyte function and, in addition, may exert an immunosuppressive effect. Free radicals, histamine, eicosanoids and platelet-activating factor have been shown to be involved in dithranol-induced dermatitis, and the oxidation products of the drug are responsible for the staining. Our experimental data suggest that extracellularly generated oxygen free radicals are responsible for both the antipsoriatic and irritative effect of the drug. Furthermore, we could recently provide evidence that extracellularly generated superoxide anion radical also induces an active adaptation mechanism resulting in increased tolerance to dithranol upon repeated application. This adaptive process may explain the requirement for increasing dithranol concentrations to maintain the antipsoriatic efficacy, and also the beneficial effect of other antipsoriatic modalities such as UV-B on dithranol-induced dermatitis. The recognition of this adaptive mechanism may open future prospects to overcome some limitations concerning the practical use of dithranol.
Topical Delivery of Ciclosporin: Evaluation of Various Formulations Using in vitro Diffusion Studies in Hairless Mouse Skin
Authors: Egbaria K. , Ramachandran C. , Weiner N.
Published: April 2009

The kinetics and extent of uptake of ciclosporin in various strata of hairless mouse skin upon topical application of several ciclosporin formulations were determined by in vitro diffusion cell experiments. The ciclosporin formulations tested included a hydroalcoholic solution, an oil-in-water emulsion and two liposomal systems. The accumulation of drug in stratum corneum is in the order: ‘skin lipid’ liposomes > ‘phospholipid’ liposomes > emulsion > hydroalcoholic solution. The total combined amount of drug in the deeper skin strata and the receiver compartment followed the order: hydroalcoholic solution > > ‘phospholipid’ liposomes > ‘skin lipid’ liposomes > emulsion. The results suggest that topically applied liposomes, particularly those prepared from lipid mixutres having compositions similar to the stratum corneum, may provide sustained, enhanced levels of ciclosporin in the stratum corneum (the reservoir) while minimizing high levels in strata associated with blood and lymph supplies.
Comparative Study of Antiseptic Toxicity on Basal Keratinocytes, Transformed Human Keratinocytes and Fibroblasts
Authors: Tatnall F.M. , Leigh I.M. , Gibson J.R.
Published: April 2009

The cytotoxic effects of a range of antiseptic agents were examined on cultured human fibroblasts and basal keratinocytes and compared to those on a transformed keratinocyte line (SVK 14 cells). Cells were exposed to chlorhexidine, hydrogen peroxide and sodium hypochlorite for 15 min and cell viability was assessed 24 h later with a colorimetric assay which utilizes the tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT). At concentrations recommended for wound cleansing all agents produced 100% killing of all cell types. The results show that fibroblasts and keratinocytes, cells which are fundamental to the wound healing process are equally sensitive to the effects of the antiseptic agents tested, and are highly susceptible to the effects of free-chlorine containing agents. These observations are of particular importance to the use of cultured keratinocytes (culture grafts) to enhance wound healing; the application of antiseptics to such wounds is contraindicated. All three cell types tested showed similar susceptibilities to the agents tested. These findings suggest that the transformed cell line, which has the advantage of immortality and ready availability, can replace fibroblasts and keratinocytes in studies designed to investigate the adverse effects of antiseptic agents in vitro. Comparison of the ED5o concentration for each agent on all cell types to the standard use concentration produced a ranking order of toxicity which showed chlorhexidine to be the least toxic agent and sodium hypochlorite the most. These findings are in agreement with recent in vivo studies on wound healing which have shown that chlorhexidine does not inhibit wound healing but that sodium hypochlorite inhibits both the formation of granulation tissue and re-epithelialization.
Objective Assessment of Topical Anti-Inflammatory Drug Activity on Experimentally Induced Nickel Contact Dermatitis: Comparison between Visual Scoring, Colorimetry, Laser Doppler Velocimetry and Transepidermal Water Loss
Authors: Queille-Roussel Catherine , Duteil Luc , Padilla Jean-Michel , Poncet Michel , Czernielewski Janusz
Published: April 2009

Four topical anti-inflammatory drugs were investigated for their effect on allergic contact dermatitis. Nickel dermatitis was chosen for its high incidence in European healthy volunteers. Experimental lesions were treated twice daily with two steroids, two non-steroidal anti-inflammatory drugs and a blank base for 4.5 days without occlusion. The influence of treatments was assessed by daily visual grading and one site was left untreated for comparison over the same period. To quantify drug activities objectively, skin colour (colorimetry), skin blood flow (laser Doppler velocimetry) and transepidermal water loss (evaporimetry) were measured before drugs were first applied, then 6 h after the last application. As expected, only Dermoval cream significantly improved the spontaneous clinical evolution in comparison with the other creams (Hydrocortisone Astier à 1 %, Parfenac, indomethacin 2.5% and Skinbase) and the untreated site. Colorimetric parameter a* (redness) and L* (luminance) showed more differences between treatments than the other criteria and a close relationship was obtained between these two parameters and skin blood flow, all three being highly correlated to visual grading. Transepidermal water loss appeared less related to clinical improvement but this parameter could prove helpful for detecting compounds which could be irritant to diseased skin.
Effect of Glycyrrhizin on Pain and HLA-DR Antigen Expression on CD8-Positive Cells in Peripheral Blood of Herpes zoster Patients in Comparison with Other Antiviral Agents
Authors: Aikawa Yosuke , Yoshiike Takashi , Ogawa Hideoki
Published: April 2009

Glycyrrhizin (GL) is a saponin widely used as an anti-inflammatory agent. Pain intensity and HLA-DR antigen expression on CD8+ cells were assessed during and after treatment with GL. Other agents such as acyclovir,γ-globulin and interferon β were also administered for comparison. Pain resolved most rapidly among those treated with acyclovir followed by those treated with GL. Pain resolution correlated with the regression of HLA-DR+ in CD8+ subpopulations in peripheral blood. GL is suggested to be an alternative or additive antiviral agent to herpes zoster.
Mouse Skin Inflammation Induced by Multiple Topical Applications of 12-O-Tetradecanoylphorbol-13-Acetate
Authors: Stanley Paul L. , Steiner Stephen , Havens Mary , Tramposch Kenneth M.
Published: April 2009

It is well known that applications of a single dose of 12-O-tetradecanoylphorbol-13-acetate (TPA) to mouse ears induces an acute inflammatory reaction consisting of erythema, edema and polymorphonuclear leukocyte (PMN) infiltration. We report here that multiple topical applications of TPA to mouse ears produce a prolonged inflammatory reaction characterized by increases in ear weight, inflammatory cell infiltration and epidermal hyperplasia. TPA was applied 5 times over 10 days to mouse ears. Epidermal thickness and PMN infiltration (myeloperoxidase content) increased 3- and 160-fold, respectively, by day 3 and remained elevated over control values throughout the test period. Ear weight was elevated from day 1 and remained high. Hydrocortisone 17-valerate and betamethasone dipropionate significantly reduced all three parameters of inflammation. Indomethacin and two other cyclo-oxygenase inhibitors, and an antihistamine had little or no effect on any of the parameters. This chronic skin inflammation model may be more relevant for evaluating anti-inflammatory compounds than the acute TPA model because the test compounds are applied after the inflammatory lesion is established, which mirrors the use of clinical anti-inflammatory drugs. Also this model may be more selective than the acute TPA model for compounds which affect leukotriene production since other pharmacological agents which are active in the acute model are not active in the multiple-application model.
Binding of 5-Methoxypsoralen to Blood Fractions
Authors: Muret Patrice , Makki Safwat , Urien Saik , Agache Pierre , Bechtel Pierre , Tillement Jean-Paul
Published: April 2009

The binding of 5-methoxypsoralen (5-MOP) to human serum and blood fractions was studied by equilibrium dialysis associated to high-performance liquid chromatography. 5-MOP serum binding was 95% and kept constant in the range of therapeutic concentrations. Albumin was the main binding protein with one class of binding sites (n = 2.05) and with a moderate affinity constant (Ka = 10,270 M-1). Free fatty acids (FFA) enhanced 5-MOP binding to albumin. Binding to other proteins, α1-acid glycoprotein, gamma-globulins and lipoproteins (LDL, HDL, VLDL) also occurred, but was negligible. 5-MOP bound to red blood cells (RBCs) with a binding index (ratio of intra- to extra-globular 5-MOP concentrations) of 3.84 and 1.48 in buffer and plasma, respectively. 5-MOP distribution in blood was simulated. The free fraction of 5-MOP in blood could be increased in hypoalbuminemia, unchanged in acute inflammation, and decreased by FFA.
Lack of Antiandrogenic Effects of Topical Bifonazole on Sebaceous Glands and Hairs in the Hamster Flank Organ
Authors: Aricò Mario , Noto Giuseppe , Pravatà Gabriella , Bongiorno Maria R.
Published: April 2009

The activity of topically applied bifonazole was evaluated in vivo in the three androgen-dependent structures of the hamster flank organ, i.e. the pigmented spot, sebaceous glands and hairs. Topical bifonazole in our experience did not demonstrate any morphological effect on sebaceous gland and hair even when applied in the dosage of 3 mg/cm2/day. On the basis of our morphometric results we can conclude that topically applied bifonazole does not interfere with cutaneous androgen metabolic transformations in the pilosebaceous unit of the flank organ.
How Does Sodium Lauryl Sulfate Alter the Skin Barrier Function in Man? A Multiparametric Approach
Authors: Lévêque J.L. , de Rigal J. , Saint-Léger D. , Billy D.
Published: April 2009

The effects of topically applied sodium lauryl sulfate were studied in vivo, in man, through noninvasive methods and compared with those obtained in vitro, using human stratum corneum as a model. The results show that the very marked increase of transepidermal water loss obtained in vivo cannot be related to any removal of epidermal lipids. The most likely explanation of our findings lies in the hyperhydration of stratum corneum consecutive to the inflammation process and a possible disorganization of the lipid bilayers.
Potassium Channel Openers Stimulate DNA Synthesis in Mouse Epidermal Keratinocyte and Whole Hair Follicle Cultures
Authors: Harmon Charles S. , Lutz Diane , Ducote Janet
Published: April 2009

We have conducted studies using primary mouse epidermal keratinocyte and whole hair follicle cultures to investigate the mechanism of the hypertrichotic activity of potassium channel openers. In a time course study, the extent of stimulation of epidermal keratinocyte DNA synthesis by minoxidil increased as the rate of DNA synthesis in control cultures declined. Minoxidil stimulation of DNA synthesis in 7-day cultures required prolonged (> 1 day) exposure to the agent. Pinacidil and diazoxide also stimulated DNA synthesis in mouse epidermal keratinocyte cultures. In addition, minoxidil, pinacidil, diazoxide, and cromakalim stimulated DNA synthesis in whole-organ cultures of mouse hair follicles. These results suggest that potassium channel openers retard the loss of proliferative activity of differentiating keratinocytes and support the hypothesis that these agents stimulate hair growth through a direct effect on hair follicles.
Influence of Calcitonin Gene-Related Peptide on Histamine- and Substance P-Induced Itch, Flare and Weal in Humans
Authors: Ekblom Anders , Lundeberg Thomas , Wahlgren Carl-Fredrik
Published: April 2009

Recent data have shown both synergistic and inhibitory effects between calcitonin gene-related peptide (CGRP) and substance P (SP) on inflammation and flare responses. The modulatory effects of CGRP on the itch, flare and weal responses following intracutaneous injections of SP and histamine were studied in 10 healthy volunteers. The only change in itch responsiveness observed was a significant prolongation of itch latency following SP when preceded 10 min earlier by a CGRP injection. No influence on flare and weal was observed.
Influence of Ageing on the in vivo Mechanics of the Skin
Authors: Lanir Yoram , Manny Vered , Zlotogorski Abraham , Shafran Abraham , Dikstein Shabtay
Published: April 2009

The response of the skin to common in vivo tests (in-plane uniaxial stretch, torsion, indentation and levarometry) is analyzed in terms of their suitability for ageing studies. The analysis suggests that low-load indentation and small deformation levarometry are well suited for ageing studies since the skin response under these tests can be directly related to its structure and constituent properties (known to be affected by ageing). The measured forehead skin response under these tests in ‘young’ (20–26 years) and ‘old’ (64–80 years) subjects is presented and compared with predictions of corresponding models. The results show that levarometry is more sensitive to ageing than indentometry.
Effects of the Avène Spring Water on the Dynamics of Lipids in the Membranes of Cultured Fibroblasts
Authors: Cézanne L. , Gaboriau F. , Charveron M. , Morlière P. , Tocanne J.F. , Dubertret L.
Published: April 2009

In this preliminary report, dealing with the biological properties of AvÈne spring water, we investigated its effects on membrane properties of cultured human skin fibroblasts used as a model cell system. It is shown that incubation of these cells in the presence of AvÈne spring water brings about an increase in the fluidity of plasma membrane. This effect was evidenced by a decrease in the fluorescence anisotropy of the lipophilic probe diphenylhexatriene and by a 3-fold increase in the lateral diffusion coefficient of the lipophilic probe 5-(N-hexade-canoyl)-aminofluorescein, as measured through fluorescence recovery after photobleaching experiments. This effect reached a maximum for incubation times longer than 30 min and for a dilution of AvÈne water in laboratory water to about 20–25%. As discussed, changes in the hydrodynamic properties of cell membranes induced by AvÈne water provide a plausible explanation for some of the biological events this spring water is known to trigger.
Metabolism of Ethyl 4-Aminobenzoate in the Isolated Single-Pass Perfused Rabbit Ear
Authors: Henrikus B. , Kampffmeyer H.G.
Published: April 2009

Isolated rabbit ears were single-pass perfused with a protein-free Tris buffer solution. Ethyl 4-amino[U-ring-14C]benzoate or 4-amino[U-ring-14C]benzoic acid was applied to the epithelial surface in isopropyl myristate, or perfused arterially. Metabolites in the effusate were extracted and separated by high-performance liquid chromatography. Five metabolites were separated from ethyl aminobenzoate and identified as aminobenzoic acid, or acid-labile conjugates from either substrate. Their chemical structure has not yet been established. One metabolite, perhaps a glycolic acid N-conjugate of ethyl 4-ami-nobenzoate, was found at about 100 times higher concentration after arterial than after dermal drug application, indicating that the quantitative metabolic patterns in skin differ depending on whether the xenobiotic reaches the enzymes of the skin by cutaneous absorption or by the blood circulation. The metabolite pattern of the skin was compared with that from rabbit or rat liver cell preparations.
Does Salicylic Acid Increase the Percutaneous Absorption of Diflucortolone 21-Valerate?
Authors: Täuber U. , Weiss C. , Matthes H.
Published: April 2009

The percutaneous absorption of diflucortolone-21-valerate (DFV) and its effect on the pituitary adrenal system were investigated during large skin area treatment (20 g ointment twice a day for 8 days) of two groups of healthy volunteers with Nerisona® and Nerisalic® ointment, respectively. Plasma levels of diflucortolone, cortisol and dehydroepiandrosterone (DHEA) were measured in both groups whereas plasma levels of salicylic acid were measured additionally in volunteers treated with Nerisalic. No differences, neither in percutaneous absorption of DFV nor in effects on cortisol and DHEA were found between the two treatment groups. There was a slight reduction in cortisol levels under both treatments, but the circadian rhythm was not disturbed. Mean salicylic acid plasma levels under high-dose topical Nerisalic treatment were about 50-fold below levels where toxicity may be expected.
5-Lipoxygenase Activation in Psoriasis: A Dead Issue?
Authors: Ford-Hutchinson Anthony W.
Published: April 2009

It has been suggested in the literature that 5-lipoxygenase activation may be an important pathological event in psoriasis and that 5-lipoxygenase inhibitors may thus have some beneficial therapeutic effect in this disease. This is because (1) neutrophil activation is a prominent feature of the disease, (2) leukotriene B4 is a potent chemotactic agent for neutrophils and is present in psoriatic lesions, (3) 5-lipoxygenase is present in human epidermis, (4) inhibition of 5-lipoxygenase may affect the disease. These concepts are questioned, and in particular it is suggested that (1) the leukotriene B4-like material found in psoriatic skin has never been shown to have the correct stereochemistry to indicate that it is 5-lipoxygenase derived, (2) there is no convincing evidence for the presence of the 5-lipoxygenase enzyme in human skin, (3) drugs purported to have some benefit in psoriasis through 5-lipoxygenase inhibitory mechanisms act through other mechanisms and (4) selective leukotriene biosynthesis inhibitors have no therapeutic utility in psoriasis. It is concluded that 5-lipoxygenase activation does not play a significant role in the pathology of psoriasis and therefore selective leukotriene biosynthesis inhibitors would have no significant role in the treatment of this disease.
Penetration and Percutaneous Absorption of Topical Retinoids
Authors: Schaefer Hans
Published: April 2009

Topical retinoids are therapeutically active at low pharmaceutical concentrations, i.e. in essence lack of penetration is not a problem. Thus studies on the cutaneous pharmacokinetics focus on the distribution pattern in the skin, the penetration pathways, the cutaneous metabolism, the systemic body load and the mode of excretion. Two basically different pathways have to be taken into account: the transepidermal pathway, which gives rise to a typical epidermal/dermal concentration gradient and which is certainly part of the mode of action in disorders of keratinization, and the transfollicular pathway, which sheds some light on the activity in follicular disorders like acne. The cutaneous part of the pharmacokinetics of retinoids depends largely on their chemical structure and thus differs. However, common features are relatively high cutaneous concentrations, whereas the spillover to the systemic compartment appears to be slow and small, giving rise to low or hardly detectable bodyloads. Concerning pharmacokinetics topical application of retinoids presents major advantages over systemic medication. They can be targeted to the intended site of action, furthermore systemic toxicity is of much lesser concern.
Evaluation of the Teratogenic Risk of Cutaneously Administered Retinoids
Authors: Buchan Peter
Published: April 2009

In current cutaneous retinoid therapy systemic exposure is low and the risk of teratogenesis appears to be limited. However, new indications, altered posologies and the introduction of new synthetic retinoids demand continuous assessment of the teratogenic risk. Teratogenicity testing of new substances in animals is only of value if accompanied by detailed pharmacokinetic analysis to establish the relationships between the levels of parent compound and metabolite in both maternal plasma and fetal tissues and teratogenic events. This information should be compared to the maximum of relevant pharmacokinetic data which can be ethically obtained in man or from human tissues. The presence or absence of teratogenic effects following cutaneous administration of retinoids in animals has, as such, little direct bearing on the risk in man. Two special cases exist where teratogenic risk can be evaluated directly in man without reference to animal studies. The first concerns substances whose teratogenic potential has been established in man by other routes of administration permitting a comparison with the cutaneous route on a pharmacokinetic basis. The second concerns the cutaneous administration of endoge-nously occurring substances and their eventual disturbance of systemic retinoid equilibrium.
Adapalene, a New Chemical Entity with Retinoid Activity
Authors: Bernard Bruno A.
Published: April 2009

Adapalene is a novel chemical entity which, in terms of pharmacology, behaves similar to tretinoin, but is chemically and photochemically stable. It has a particular selectivity profile for the known nuclear retinoic acid receptors with low affinity for RARΑ and no transactivating potential for RXRΑ. This receptor profile could imply that adapalene, in contrast to tretinoin, affects the terminal differentiation pathway of epidermal cells rather than their proliferation. Furthermore, adapalene does not bind to members of the cellular retinoic acid binding protein family. Adapalene has comedolytic activity in the topical rhino mouse model. It exerts a moderate-to-potent anti-inflammatory effect in a series of in vitro and in vivo models. In comparative clinical studies involving 72 acne patients, the efficacy of adapalene was comparable, if not superior, to tretinoin, but adapalene was better tolerated. The data reviewed in this paper indicate that adapalene should be particularly beneficial in the treatment of acne.
Topical Retinoic Acid for Photoaging: Clinical Response and Underlying Mechanisms
Authors: Griffiths Christopher E.M. , Voorhees John J.
Published: April 2009

Photoaging is primarily composed of wrinkling, mottled hy-perpigmentation and a tactile roughness of the skin, all three of these parameters improve following use of topical retinoids. It appears that smoothening of the skin results from a combination of epidermal changes including thickening, stratum corneum compaction and glycosaminoglycan deposition. Lightening of actinic lentigines and mottled hyperpigmenta-tion correlates with a reduction in epidermal melanin content maybe resulting from inhibition of tyrosinase activity. Effacement of wrinkling in mice correlates with new collagen synthesis, and there is evidence that this is also the case in humans. An irritant dermatitis is a feature of retinoid-treated skin but this diminishes in severity during treatment despite continued improvement in photoaging. Thus it is unlikely that irritation per se is responsible for clinical improvement.
Pro-Inflammatory Cytokine Cascade in Human Plucked Hair
Authors: Mahé Yann F. , Buan Bruno , Billoni Nelly , Loussouarn Geneviêve , Michelet Jean-François , Gautier B. , Bernard Bruno A.
Published: April 2009

Using reverse transcriptase polymerase chain reaction we showed that freshly plucked human anagen hair expressed both type 1 (80 kD) and type 2 (60 kD) interleukin (IL)-1 receptor mRNAs. The IL-1 receptor type 1 was functional since after in vitro stimulation of plucked hair with IL-1Α, we observed the induction of mRNA(s) for the inflammatory cytokines IL-1Β, tumour necrosis factor Α and IL-6 as well as for the chemokines monocyte chemotactic and activating factor and IL-8. In addition, the growth of dissected human anagen hairs in culture in vitro was significantly and dose-depen-dently inhibited by IL-1Α as a consequence of hair bulb degradation. These observations, together with those of other authors in IL-1Α transgenic mice evidence the inhibitory role of IL-1 on human hair growth. Therefore, in order to identify individuals with high inflammatory potential in their hair follicle environment, we designed a rapid and simple assay to detect variations in the level of IL-1Α production in the overnight supernatant of plucked hairs in culture. We observed that 32.7% of the specimens from the volunteers tested (n = 116) could be considered highly inflammatory in terms of IL-1Α production. Altogether, these results suggest that in alopecia androgenetica, hair growth might be negatively influenced by IL-1, directly produced by the outer root sheath keratinocytes. Consequently, identifying the ‘inflammatory alopecic individual’ might be of clinical interest to discriminate among individuals for whom anti-IL-1 strategies might be of therapeutic relevance.
Toxicology of Topical Local Anesthetics
Authors: Bangha E. , Maibach H.I. , Elsner P.
Published: April 2009

Topical anesthesia of the skin, nowadays performed for various indications from pruritus over postherpetic neuralgia to minor surgery, has been under investigation for more than 30 years. Due to low water solubility, the active base form of most of the local anesthetics on the market is poorly absorbed through the skin. Hence, the most challenging target was to develop galenic preparations which provide a good skin penetration in order to reach the dermal nerve endings and thereby lead to sufficient local anesthesia. On the other hand good skin penetration also results in a distribution of the drug in the circulation. Since local anesthetic agents are known to have an impact on the heart and central nervous system, unwanted side effects following topical application onto the skin are worth discussing. This article reviews the current topical local anesthetics with particular accent on their pharmacological and toxicological data.
Transcriptional Activation by 1,25-Dihydroxyvitamin D3 and Synthetic Vitamin D3 Analogues in Transfected Cultures of Human Keratinocytes
Authors: Henriksen Linda Ø. , Kragballe Knud , Jensen Thomas G. , Fogh Karsten
Published: April 2009

Analogues of vitamin D3 have recently been introduced for the topical treatment of psoriasis. Their therapeutic effects are thought to be mediated by interaction with the vitamin D3 receptor (VDR) in epidermal keratinocytes (KCs). The purpose of the present study was to investigate the trans-acting activity of the endogenous VDR in human KCs transfected with a vitamin D response element (VDRE) in response to 1,25-dihydroxÝvitamin D3 [1,25(OH)2D3] and the synthetic vitamin D3 analogues GS 1500, EB 1213, MC 903 (calcipotriol) and KH 1060. Cultured KCs obtained from normal human adults were transfected with a VDRE consisting of a direct repeat (DR) of 2 hexanucleotides separated by 3 nucleotides (AGGTCAaggAGGTCA) cloned as a triple copy into the chloramphenicol acetyltransferase (CAT) reporter plasmid pBLCAT2. This DR3 response element is preferentially activated by heterodimers of the VDR and the retinoid X receptor. Twenty-four hours after transfec-tion, 1,25(OH)2D3, vitamin D3 analogues or 9-cis-retinoic acid (9-cis-RA) were added, and, after an additional 24 h, cells were harvested and assayed for CAT activity. 1,25(OH)2D3 dose-dependently induced CAT activity in VDRE-transfected KCs and co-transfection with exogenous human VDR enhanced the response to 1,25(OH)2D3. Induction of CAT activity by 1,2 5 (OH) 2D3 was enhanced in the presence of the endogenous ligand for retinoid X receptor, 9-cis-RA. The synthetic vitamin D3 analogues dose-dependently stimulated CAT activity. Compared to 1,25(OH)2D3, KCs were less sensitive to stimulation with MC 903, equally sensitive to EB 1213 and more sensitive to GS 1500 and KH 1060. In conclusion, the endogenous VDR in KCs is responsive to 1,25(OH)2D3 and its synthetic analogues in stimulating gene transcription. To the extent that the biological actions of vitamin D3 are dependent on its ability to induce gene transcription through the endogenous VDR, this transfection model may be used in the screening of novel vitamin D3 analogues for biological activity.
Vehicle-Dependent Biotin Liberation and Penetration into Human Skin
Authors: Wagner C. , Göbel S. , Wohlrab W. , Neubert R.
Published: April 2009

The presence of a sufficient quantity of a drug in the epidermis is a necessary prerequisite for influencing epidermal proliferation and differentiation processes. With the aim of obtaining a high concentration of a potential active agent (biotin) at the target area after topical application, the influence of the vehicle on biotin release and penetration was investigated. Liberation studies (multi-layer membrane model) showed that over 50% of the biotin in an oil-in-water (O/W) emulsion (64.8 ± 1.9%) and a micro-emulsion (ME, 54.5 ± 2.4%) is released within 300 min, whereas the degree of release from a water-in-oil emulsion does not exceed 16%. For this latter vehicle, the influence of a controlled drug release on the penetration processes in human skin (Franz cell) results in the penetration of only small quantities of the drug into the skin layers (into the horny layer 7.9 ± 2.6%, living epidermis 0.11 ± 0.06%, dermis 0.38 ± 0.31% within 300 min). The application of an O/W emulsion or an ME appears to be more favourable. Both vehicles lead to not only a large reservoir in the horny layer (O/W 26.5 ± 3.5%, ME 26.0 ± 0.8% within 300 min) of the skin but also important epidermal and dermal concentrations (living epidermis: O/W 2.0 ± 0.9%, ME 0.3 ± 0.2%; dermis: O/W 3.4 ± 1.3%, ME 1.6 ± 0.8% within 300 min). The time-dependent concentration profiles in the skin layers suggest that the use of an ME produces an immediate effect, whereas the application of an O/W emulsion results in a delayed and/or long-term effect.
Topical Retinol and the Stratum corneum Response to an Environmental Threat
Authors: Goffin Véronique , Henry Frédérique , Piérard-Franchimont Claudine , Piérard Gérald E.
Published: April 2009

The functional consequences of using topical retinol on skin have not been thoroughly studied so far. The aim of this open study was to compare two preparations containing either retinol or vitamin E, using biometric evaluations. Three methods, namely the sodium lauryl sulfate (SLS) corneosurfametry bioassay, the ultraviolet (UV) squamometry test and optical profilometry of the UV-induced wrinkling process, were used to assess some properties of the stratum corneum. The retinol preparation achieved better scores than the vitamin-E cream in all three tests and appears to improve the resistance of the stratum corneum against some chemical (SLS) and physical (UV) threats. It also limits UV-induced shallow wrinkling.
Oxyhemoglobin Is a Quantifiable Measure of Experimentally Induced Chronic Tretinoin Inflammation and Accommodation in Photodamaged Skin
Authors: KolIias N. , Gillies R. , Muccini J.A. , Phillips S.B. , Drake L.A.
Published: April 2009

Chronic exposure to a weak irritant leads to inflammatory changes which may be followed by pigmentary changes and accommodation. The inflammatory responses to acute exposure to an irritant have been extensively studied. This study investigated quantitatively the inflammatory reactions produced in photodamaged skin with chronic application of a weak chemical irritant (tretinoin cream 0.025%) over a period of 9 months (36 weeks). Forty-eight subjects with moderately to severely photodamaged skin were enrolled in a 36-week, double-blind placebo-controlled study. Tretinoin cream was applied nightly on the distal two thirds of one dorsal forearm and placebo on the other. The proximal third of each dorsal forearm received no treatment and served as control. Clinical assessments and diffuse reflectance measurements were made at 7 time points during treatment. Apparent concentrations of oxyhemoglobin (HbO2), deoxyhemoglo-bin (Hb) and melanin were estimated by analysis of the diffuse reflectance spectra. No changes were observed in the apparent H bO2or the Hb concentration of the placebo-treated or control sites, thus establishing a reliable baseline. The apparent HbO2 concentration of the tretinoin-treated sites increased significantly from baseline to a maximum at 12-18 weeks of treatment, then returned to baseline with continued applications. The changes in HbO2 concentration agreed closely with clinical assessments of erythema. The apparent melanin concentration, corresponding to diffuse hyperpigmentation, showed a large seasonal decrease in both the control and the treated sites, with an additional decrease in the treated sites between 12 and 18 weeks. Erythema appeared after repeated applications and eventually resolved under continuous treatment. The maximum decrease in hyperpigmentation occurred simultaneously with the maximum increase in erythema.
Immunological Gene Therapy Approaches for Malignant Melanoma
Authors: Bonnekoh Bernd , Bickenbach Jackie R. , Roop Dennis R.
Published: April 2009

Immuno-gene therapy approaches for the treatment of malignant melanoma are categorized into two major subgroups according to an active or passive immunological principle. Active immuno-gene therapy is subdivided into melanoma cell vaccines, DNA-based vaccinations and the treatment of pre-existing tumor tissue by cell-mediated or direct transfer of cytokine and/or cell surface signal genes. Passive immuno-gene therapy, employing an adoptive treatment with in vitro activated and expanded anti-tumor effector cells, involves two major application fields for gene transfer techniques, first the genetic modification of the effector cells, and second the in vivo amplification of pre-effector cells by procedures also used in active immuno-gene therapy. Corresponding preclinical studies are reviewed. The clinical studies inaugurated during the last few years are mostly still ongoing and focus on treatment safety and tolerability rather than efficacy. A recent trend is emerging to explore recombinant adenovirus and vaccinia virus vectors particularly with regard to in vivo gene transfer applications. Overall, immuno-gene therapy of melanoma is still in a highly experimental stage of development but may become a safe, efficacious and practical adjuvant treatment modality in the future.
Activity and Inhibition of 3-Beta-Hydroxysteroid Dehydrogenase/Delta-5-4-lsomerase in Human Skin
Authors: Tóth Istvá;n , Szécsi Mihá;ly , Julesz Já;nos , Faredin Imre
Published: April 2009

Activity and inhibition of 3Β-hydroxysteroid dehydrogenase/ Δ5-4-isomerase, a key enzyme of biosynthesis of androgenic steroids, in human skin were studied. Whole-width dermal tissue specimens excised from various regions of the male and female body were investigated with an in vitro radioenzyme assay method using dehydroepiandrosterone as substrate. The Michaelis-Menten constant of the enzyme was found to be Km=10 nM and the maximal velocity was Vmax = 0.625 pmol produced 4-androstene-3,17-dione/mg protein/20 min. Activity of 3 Β-hydroxysteroid dehydrogenase/Δ5-4-isomerase in male inguinal skin (n = 8) was 0.132-0.412, in female abdominal skin (n = 4) 0.140-0.255, in perineal skin (n = 4) 0.138-0.962 pmol/mg protein/20 min. The synthetic steroids cyproterone acetate, 4-MA and epostane proved to be potent inhibitors, IC50 values were 150, 6.2 and 1.45 nM, respectively.
Effects of Flavonoids of Ginkgo biloba on Proliferation of Human Skin Fibroblast
Authors: Kim Seong-Jin , Lim Mi-Hye , Chun Inn-Ki , Won Young-Ho
Published: April 2009

Ginkgo bilobα studies have focused on the anti-inflammatory effects of the major components, ginkgolide and bilobalide, whereas little is known about their effect on fibroblasts. This study demonstrated the enhancing effects of Ginkgo L. extracts, especially the fiavonoid fractions: quercetin, kaempfe-rol, sciadopitysin, ginkgetin, isoginkgetin, on the proliferation of normal human skin fibroblast in vitro measured by MTT (3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyl-tetrazolium bromide) assay and direct hemocytometer cell count. Furthermore, increased production of collagen and extracellular fi-bronectin were documented by radioisotope (2,3-3H-proline) incorporated collagen assay, procollagen type I C-peptide assay and by immunoturbidimetric assay. These proliferative effects suggest another useful pharmacologic application of Ginkgo L. extracts in addition to their well-known anti-inflammatory effect.
Absorption of Topical Tacrolimus (FK506) in vitro through Human Skin: Comparison with Cyclosporin A
Authors: Lauerma Antti I. , Surber Christian , Maibach Howard I.
Published: April 2009

Cyclosporin A (CsA) is efficacious in many dermatoses as an oral but not as a topical form, while tacrolimus (FK506) has been shown to be effective in both forms. As inadequate skin absorption has been proposed as the reason for inefficacy of topical CsA, factors contributing to percutaneous absorption of FK506 and CsA were studied. Partitioning of FK506 and CsA between octanol and water, stratum corneum and water, and stratum corneum and isopropyl myristate was determined. Absorption of FK506 and CsA through dermatomed human cadaver skin was determined with in vitro flow-through cells. In partitioning experiments, CsA was more lipo-philic than FK506. Both drugs were seen in comparable amounts in skin layers, but FK506 permeated the skin to a greater extent than CsA.
Morphologic Basis for a Pore-Pathway in Mammalian Stratum Corneum
Authors: Menon Gopinathan K. , Elias Peter M.
Published: April 2009

Although prior morphologic studies have shown that both polar and nonpolar materials permeate across the stratum corneum (SC) via a paracellular route, the actual pathway through these heterogeneous domains is unknown. We applied hydrophilic and hydrophobic tracers in vivo to murine skin under basal conditions and/or after permeation enhancement with occlusion, vehicle enhancers, a lipid synthesis inhibitor, sonophoresis, and iontophoresis. Ruthenium tetroxide, ruthenium red plus osmium tetroxide, in situ precipitation with osmium vapor, and microwave postfixation methods were used to visualize penetration pathways. Tracers invariably localized to discrete lacunar domains, embedded within the extracellular lamellar membrane system, regardless of their polarity or the enhancement method. Moreover, while the lacunar domains remained discontinuous under basal conditions, they appeared to gain structural continuity with permeation enhancement. These results indicate that extracellular lacunar domains comprise a pore pathway for penetration of polar and nonpolar molecules across the SC.
Barrier Function of Reconstructed Epidermis at the Air-Liquid Interface: Influence of Dermal Cells and Extracellular Components
Authors: Robert M. , Dusser I. , Muriel M.-P. , Noë;l-Hudson M.-S. , Aubery M. , Wepierre J.
Published: April 2009

To evaluate the epidermal barrier function of in vitro reconstructed epidermis, we measured the penetration of estradiol and water across human keratinocytes cultured in defined medium (DM), in the presence of proliferative fibroblasts (pF) or conditioned medium derived from pF, at the air-liquid interface on synthetic porous membrane, noncoated or coated with laminin, fibronectin, type I collagen or type IV collagen. Ultrastructural analysis showed a well-developed stratum corneum whatever the culture conditions. The permeability of reconstructed epidermis in DM on a noncoated porous membrane was 5- to 10-fold higher than human native epidermis, with both tracers. No significant change in barrier function was observed whatever the culture conditions.
In vitro Susceptibility Testing of Malassezia furfur against Rilopirox
Authors: Nenoff Pietro , Haustein Uwe-Frithjof
Published: April 2009

The in vitro antifungal activity of the new hydroxypyridone antimycotic rilopirox has been evaluated against 29 separate clinical isolates of Mαlαsseziα (M.) furfur obtained from patients with pityriasis versicolor, seborrhoeic dermatitis or dandruff. Minimum inhibitory concentrations (MICs) of rilopirox were measured by the agar dilution technique and, in comparison, by a recently described microdilution method with colorimetric detection of the MIC end points. Rilopirox was found to be able to inhibit growth of all clinical yeast isolates. For the investigated M. furfur strains MIC values from 12.5 to 50 µg ml-1 with a median of 25 µg ml-1 were determined by the agar dilution method. Using the microdilution technique, MIC values between 16 and 128 µg ml-1 (median 32 µg ml-1) were found for the M. furfur isolates. It has to be taken into account that with a 0.3% solution concentrations of 300,000 µg ml-1 are applied to the skin. Furthermore, due to its extreme low penetration rilopirox is long-term available in the skin in inhibiting concentrations. In comparison with rilopirox, the in vitro susceptibility of M. furfur against the systemically applicable triazole antimycotic itraconazole and clotrimazole, an established topical antifungal, was tested. As expected, low MIC values for these azoles were found by the agar dilution method. The median of the MIC of M. furfur was 0.1 µg ml-1 for itraconazole, and 6.25 µg ml-1 for clotrimazole. The inhibitory effectivity of rilopirox against clinical isolates of M. furfur seems to justify its therapeutic evaluation in clinical trials. This new antifungal may be a useful alternative not only in pityriasis versicolor but also in seborrhoeic dermatitis due to the growth inhibition of M. furfur.
Effect of Topical Corticosteroids on the Activity of Superoxide Dismutase in Human Skin in vitro
Authors: Gavan Norina , Maibach Howard
Published: April 2009

We measurd the superoxide dismutase (SOD) activity in human skin from tissue homogenates after topical application of hydrocortisone-21 -acetate and clobetasol proprionate, dissolved in propylene glycol. SOD was measured spectropho-tometrically. SOD activity was higher in the treated skin than in the control untreated skin. We separated epidermis from the dermis by curettage and measured the level of SOD in each homogenized layer; SOD activity was higher in the epidermis compared to the dermis in untreated skin. After corticoid application, SOD activity was higher in the dermis compared to the epidermis to a degree dependent on corticoid potency. These experiments demonstrate that the epidermis may have a role in the barrier function of the skin by its antioxidant capacity and that the dermis is the major location of the metabolic activity in the skin. On the other hand, our results suggest that these corticosteroids may stimulate SOD production and may release antioxidants. This could be another anti-inflammatory property of corticosteroids.
Effects of either Tibolone or Continuous Combined Transdermal Estradiol with Medroxyprogesterone Acetate on Coagulatory Factors and Lipoprotein(a) in Menopause
Authors: Perrone G. , Capri O. , Galoppi P. , Brunelli R. , Bevilacqua E. , Ceci F. , Ciarla M.V. , Strom R.
Published: April 2009

Background/Aim: The aim of this prospective controlled study was to compare the effects of two therapies for menopause on factor VII (FVII) and hemostatic variables. Methods: Postmenopausal women were assigned to receive one of the following treatments: transdermal estradiol (TTS E2; 50 μg) combined in a continuous sequential regimen with oral medroxyprogesterone acetate (MPA; 10 mg/day for 12 days) (group A; n = 20), tibolone (2.5 mg/day) (group B; n = 21) or placebo (group C; n = 19). Sixty women completed the 1-year treatment and underwent follow-up examinations after 3, 6 and 12 months. Results: TTS E2/MPA induced various changes in procoagulatory factors. At 12 months, fibrinogen, activated FVII (FVIIa) and coagulative FVII (FVIIc) had increased by 10.7, 12.9 and 3.7%, respectively. Among the fibrinolytic factors, plasminogen and α2-antiplasmin increased by 11.3 and 7.2%, respectively. Lipoprotein(a) [Lp(a)] and antithrombin III (ATIII) did not show any significant variation. Tibolone induced some changes toward a more homogeneous antithrombotic profile. Fibrinogen, FVIIa and FVIIc decreased significantly by 7.5, 8.1 and 21.3%, respectively. Plasminogen increased (by 11.8%) and Lp(a) decreased (by 28.4%). ATIII was unchanged with tibolone therapy. Conclusion: Our results show that tibolone induces a significant reduction in FVIIc and Lp(a) and a greater enhancement of factors promoting fibrinolysis than the TTS E2/MPA regimen.