Biomedical subjects

H Löffler

Publications and source records attributed to H Löffler.

At least 19 recordsLinked to original sources

PubMed2006

Dose-dependent induction of IL-6 by plant-derived proteases in vitro.

Oral administration of proteases such as bromelain and papain is commonly used in patients with a wide range of inflammatory conditions, but their molecular and cellular mechanisms of action are still poorly understood. The aim of our study was to investigate the impact of these proteases on the release of interleukin-6 (IL-6) and other cytokines in the recently described modified mixed lymphocyte culture (MMLC) test system which is based on the mutual interaction of cells of the innate and adaptive immunity. Bromelain and papain enhanced IL-6 production dose-dependently up to 400-fold in MMLC before and up to 30-fold after neutralization of LPS content of proteases using polymyxin B, indicating that IL-6 induction by protease treatment was attributable to both protease action and LPS content of enzyme preparations. The production of IFNgamma and IL-10 was not altered by bromelain or papain, indicating a selective and differential immune activation. Both proteases impaired cytokine stability, cell proliferation and expression of cell surface molecules like CD14 only marginally, suggesting no impact of these mechanisms on protease-mediated cytokine release. These findings might provide the mechanistic rationale for the current use of proteases in wound healing and tissue regeneration since these processes depend on IL-6 induction.

Analysis of Variance↗

PubMed2005

Tegaserod is effective in the initial and retreatment of irritable bowel syndrome with constipation.

BACKGROUND: Symptoms of irritable bowel syndrome are often cyclical and thus may require repeated rather than continuous therapy. Tegaserod is effective and well-tolerated for irritable bowel syndrome with constipation but data on retreatment are lacking. AIM: To assess whether tegaserod retreatment is as efficacious and well-tolerated as initial treatment in a primary care setting. METHODS: This open-label trial was designed to evaluate the effectiveness of tegaserod under real-life conditions. Irritable bowel syndrome with constipation patients received tegaserod 6 mg b.d. for 12 weeks; response was assessed at weeks 4 and 12. Responders (those achieving satisfactory relief for at least 2 of the previous 4 weeks) at weeks 4 and/or 12 entered an 8-week withdrawal period where symptom recurrence was assessed. Patients experiencing recurrence could receive tegaserod 6 mg b.d. for another 4 weeks (retreatment phase) and on completion, could choose to continue tegaserod in a 6-month extension study. RESULTS: A total of 513 patients received initial treatment with tegaserod; 85.0% (436 of 513) responded. 403 responders entered the withdrawal period; symptoms recurred in 83.9% (338 of 403) after a mean of 38 days. Of the 307 patients who subsequently entered retreatment 89.3% (274 of 307) responded. Among patients entering the retreatment period, 269 (87.6%) had responded within the first 4 weeks of initial treatment. Of these, 243 (90.3%) responded to tegaserod retreatment. Adverse events were infrequent and similar during 4 weeks of the initial treatment period (11.1%) and on retreatment (10.4%). The extension study, completed by 188 of 232 (81.0%) patients, demonstrated good long-term tolerability of tegaserod. CONCLUSIONS: Irritable bowel syndrome with constipation patients can be successfully treated, and retreated, with tegaserod 6 mg b.d. Tegaserod was well-tolerated during initial and retreatment periods.

Adolescent↗

PubMed2005

[Clinical trials in Germany and in the EU in the new legislative environment. An analysis from the industry's point of view].

The European Union's (EU) Directive 2001/20/EC and its accompanying directives and guidance aim at approximating laws, regulations and administrative provisions relating to the implementation of Good Clinical Practice and Good Manufacturing Practice in the conduct of clinical trials on investigational medicinal products for human use in the EU member states. In addition, the establishment of two European databases for collecting information on clinical trials and suspected unexpected serious adverse events, respectively, should increase the transparency of clinical trials in the EU and thus improve patient safety. Some member states have not implemented the EU directive yet, others have implemented modified requirements, i.e. the pharmaceutical industry in the EU is confronted with different national solutions for specific aspects of the conduct of clinical trials. For industry, this creates additional work and expense. There is the hope that patient safety will be improved by these measures. The future task of all involved stakeholders will be to work on a harmonisation of the different requirements in order to achieve the original goals intended by the Directive 2001/20/EC.

Clinical Trials as Topic↗

PubMed2005

Gender aspects in chronic myeloid leukemia: long-term results from randomized studies.

Gender-related aspects in chronic myeloid leukemia (CML) have not been studied well. We therefore analyzed 856 patients with Ph/BCR-ABL-positive CML from the German randomized CML-studies I (interferon alpha (IFN) vs hydroxyurea (HU) vs busulfan) and II (IFN+HU vs HU alone). The median observation time was 8.6 years. A total of 503 patients (59%) were male. Female patients were older (51 vs 46 years; P<0.0001), presented with lower hemoglobin (11.7 vs 12.5 g/dl; P<0.0001), higher platelet counts (459 vs 355 x 10(9)/l; P<0.0001), smaller spleen size (3 vs 4 cm below costal margin; P=0.0097), a lower rate of additional cytogenetic aberrations (9 vs 15%; P=0.018) and a less favorable risk profile (P=0.036). The transplantation rate was 14% for female (n=48) and 22% for male patients (n=113). Median survival was longer in female patients (58 vs 49 months; P=0.035) mainly attributable to better survival in the low- and intermediate-risk groups and, independent from risk groups, in the HU group. These results were confirmed by matched-pair analyses based on German population data (n=496, 59 vs 45 months; P=0.0006). This is the first analysis of gender aspects in CML using randomized trials. It demonstrates the relevance of analyses of gender differences in CML and in malignant disease at large.

Adult↗

PubMed2005

Quantitative patch and repeated open application testing in methyldibromo glutaronitrile-sensitive patients.

Contact allergy to methyldibromo glutaronitrile (MDBGN), often combined with phenoxyethanol (PE) (e.g., Euxyl K 400), increased throughout the 1990s in Europe. Consequently, in 2003, the European Commission banned its use in leave-on products, where its use concentration was considered too high and the non-sensitizing use concentration as yet unknown. The 2 objectives of the study are (a) to find a maximum non-eliciting concentration in a leave-on product in MDBGN/PE-sensitized patients, which could possibly also be considered safe regarding induction and (b) to find the best patch test concentration for MDBGN. We, therefore, performed a use-related test (ROAT) in patients sensitized to MDBGN/PE (n = 39) with 3 concentrations of MDBGN/PE (50, 100 and 250 p.p.m. MDBGN, respectively). A subset of these patients (n = 24) was later patch-tested with various concentrations (0.1, 0.2, 0.3 and 0.5% MDBGN, respectively). 15 patients (38%, 95% confidence interval (CI) = 23-55%) had a negative and 24 (62%; 95% CI = 45-77%) a positive overall repeated open application test (ROAT) result. 13 reacted to the lowest (50 p.p.m.), 8 to the middle (100 p.p.m.) and 3 to the highest concentration (250 p.p.m.) only. In those 13 reacting to the lowest ROAT concentration, dermatitis developed within a few days (1-7). The strength of the initial and the confirmatory patch test result, respectively, and the outcome of the ROAT were positively associated. Of the 24 patients with a use and confirmatory patch test, 15 reacted to 0.1% MDBGN, 16 to 0.2%, 17 to 0.3% and 22 to 0.5%. With the patch test concentration of 0.5%, the number of ROAT-negative patients but patch-test-positive patients increases considerably, particularly due to + reactions. A maximum sensitivity of 94% (95% CI = 70-100%) is reached with a patch test concentration of 0.2%, and is not further improved by increasing the concentration. However, the specificity decreases dramatically from 88 (95% CI = 47-100%) with 0.2% to a mere 12.5% (95% CI = 0-53%) with 0.5%. It can be concluded (a) that for MDBGN 0.2% is very likely the best patch test concentration and (b) that 50 p.p.m. in a leave-on product can elicit contact dermatitis in sensitized persons. We were, therefore, unable to find a safe, still microbicidal, concentration for leave-on products. By contrast, with other contact allergens, dose-response use tests may be able to identify a non-eliciting concentration, which could give valuable clues to a non-inducing (i.e., safe) concentration in products.

Adult↗

PubMed2005

Simultaneous sodium lauryl sulphate testing improves the diagnostic validity of allergic patch tests. Results from a prospective multicentre study of the German Contact Dermatitis Research Group (Deutsche Kontaktallergie-Gruppe, DKG).

BACKGROUND: There is evidence that a higher skin susceptibility may induce nonspecific erythematous or weak positive reactions to contact allergens in patch testing. OBJECTIVES: To evaluate whether simultaneous application of sodium lauryl sulphate (SLS) along with diagnostic patch tests with contact allergens can provide information regarding skin irritability which may help to discriminate allergic from nonspecific irritant reactions to contact allergens. METHODS: Between July 2001 and June 2003, this prospective study collected patch test data of 5971 patients from 19 centres in Germany and Austria in the Information Network of Departments of Dermatology (IVDK). In addition to contact allergens (standard series and eight known 'problematic' allergens with a low reaction index and a high positivity ratio: 1,3-diphenylguanidine, amerchol L-101, benzalkonium chloride, benzoyl peroxide, cocamidopropyl betaine, octyl gallate, phenyl mercuric acetate and propylene glycol), patches with SLS 0.5% and 0.25% aq. were applied. Reactions to the allergens and to SLS were analysed at the IVDK data centre. The association between an erythematous or positive reaction to a certain allergen and an irritant reaction to SLS was assessed with logistic regression analysis, at the same time controlling for the influence of age and sex. RESULTS: Of the 29 allergens of the standard series, 23 and 21 gave a higher percentage of nonspecific erythematous reactions in patients with an irritant reaction to 0.25% and 0.5% SLS, respectively, in comparison with SLS-negative patients. All eight 'problematic' allergens gave an increased percentage of nonspecific erythematous reactions. Similarly, 22 and 21 allergens of the standard series gave a higher percentage of positive allergic reactions in patients with an irritant reaction to 0.25% and 0.5% SLS, respectively, and seven of the eight 'problematic' allergens gave a higher percentage of positive allergic reactions (exception: octyl gallate). For most allergens, the markers of skin reaction (reaction index and positivity ratio) were worse in SLS-positive patients. Differences were more pronounced when testing with SLS 0.25% than with SLS 0.5%. CONCLUSIONS: Because there is a convincing association between skin irritability (evaluated by SLS test) and the degree of skin reaction to contact allergens, the SLS test may help in deciding whether a doubtful erythematous or weakly 'positive' skin reaction should be interpreted as allergic or irritant.

Adult↗

PubMed2004

Modern diagnostics in chronic myeloproliferative diseases (CMPDs).

According to the new WHO classification a group of chronic myeloproliferative diseases (CMPDs) were defined: chronic myeloid leukemia (CML), chronic neutrophilic leukemia (CNL), chronic eosinophilic leukemia and hypereosinophilic syndrome (CEL/HES), polycythemia vera (PV), chronic idiopathic myelofibrosis (with extramedullary hematopoiesis, CIMF), essential thrombocythemia (ET), and so called CMPD/unclassifiable. As clinical features and laboratory findings differ widely between these diseases several diagnostic approaches are mandatory at diagnosis for classification and are needed also for follow up studies, especially for the measurement of minimal residual disease (MRD). We here outline the laboratory set up at diagnosis and during follow up in CMPDs with specific focus on the respective therapeutical consequences. Only by using a comprehensive diagnostic panel including cytomorphology, cytogenetics, and molecular genetic methods establishing the correct diagnosis, optimizing treatment as well as evaluating treatment response is possible in CMPDs today.

Blood Cell Count↗

PubMed2004

Artificial disruption of skin barrier prior to irritant patch testing does not improve test design.

BACKGROUND: Irritant patch testing is often performed as a 24- or 48-h occlusive patch test with low concentrations of sodium lauryl sulphate (SLS). OBJECTIVES: The aim of this study was to investigate potential ways to shorten this test procedure and obtain precise test results. PATIENTS AND METHODS: Thirty-six healthy volunteers underwent irritant patch testing with different pretreatments (PT) of the test fields. Occlusive test chambers were applied on the upper back with SLS 0.5%, 1%, 2% and 5% in large Finn Chambers(R). The patches were removed after 4 and 24 h, respectively, depending on the concentration used. Test fields were pretreated as follows: PT 0, field without any PT (control); PT 1, prick with lancet; PT 2, prick with test stamp; PT 3, scratch with lancet; PT 4, incision with standardized incision instrument (0.1-0.2 mm depth). Skin reactions were evaluated by transepidermal water loss (TEWL), skin erythema and skin hydration and as well by a visual score (VS) at 4, 24 and 72 h. RESULTS: Our data show an obvious distinction between PT 0-2 and PT 3-4 at all measurement methods. The average TEWL values with PT 3-4 were higher than those with PT 0-2, especially on the 4-h course. This distinction may derive from the shape and size of the skin impairment achieved by PT 3-4, leading to a mechanical barrier disruption. However, SLS may infiltrate directly into deeper skin layers supported by capillarity. Consequently, no or little penetration through the epidermis and interaction with its structures occurs, which is responsible for irritant skin reactions. The SLS dose in the upper skin layers is therefore lower at these PTs. The lower remaining dose of SLS also explains this distinction, especially for the VS. Additionally, there are presumed reactions in deeper layers of the epidermis and dermis at PT 3-4. CONCLUSIONS: In summary, all data suggest a different reaction pattern from the classical irritant response. Therefore, application without any PT seems to be best suited for irritancy skin testing, especially for visual assessment. PTs prior to irritant patch testing have been shown to be unjustifiable.

Adult↗

PubMed2004

Stratum corneum adhesive tape stripping: influence of anatomical site, application pressure, duration and removal.

BACKGROUND: Tape stripping is a common method for investigating stratum corneum (SC) physiology as well as bioavailability and bioequivalence of topical drugs. OBJECTIVES: To investigate the influence of procedures (anatomical site, pressure, pressure duration, tape removal rate) inherent in each stripping protocol on changes in skin physiology. METHODS: Tape stripping was performed using tapes on the forearm, forehead and back. On the forearm different pressures (165 and 330 g cm(-2)), durations of pressure (2 and 10 s), and removal rate (slow and rapid removal) were used. Changes in skin physiology were evaluated by measurement of transepidermal water loss (TEWL) and hydration. RESULTS: A significant influence of all parameters on the TEWL increase as a function of tape strip number was observed. The fastest increase was demonstrated on the forehead, followed by the back and, lastly, the forearm. Rapid removal produced a protracted increase in comparison with slow removal. Pressure for 10 s induced a faster increase in TEWL than 2 s pressure. Likewise, pressure at 330 g cm(-2) induced an earlier increase than pressure at 165 g cm(-2). Skin hydration was not influenced by the variables tested. CONCLUSIONS: Tape stripping results are influenced dramatically by all investigated parameters. A dynamic SC stress test to investigate SC cohesion more closely is proposed based on the present observations.

Adhesives↗

PubMed2003

Dermatological aspects of a successful introduction and continuation of alcohol-based hand rubs for hygienic hand disinfection.

With the new Centers for Disease Control and Prevention (CDC) guideline on hand hygiene, hospitals often introduce alcohol-based hand rubs for hand disinfection. Healthcare workers, however, may reject the new products because of skin irritation or other skin-related problems, which they experience after years of handwashing. In order to facilitate a successful introduction and continued use of alcohol-based hand rubs in hospitals, we have reviewed and summarized the major studies on the topic. Occupational hand dermatitis may occur in up to 30% of healthcare workers. It is mainly described as an irritant contact dermatitis caused by detergents. The diagnosis is usually clinical. Allergic reactions are very rare. After using an alcohol-based hand rub for the first time, healthcare workers may have a burning skin sensation that can be explained by pre-irritated skin. In this case the skin barrier has usually been impaired by frequent handwashing or occlusive gloves. This may result in a vicious circle whereby the healthcare worker increases the frequency of handwashing and reduces the frequency of hand disinfection. Prevention of irritant contact dermatitis is possible by selection of a low-irritating hand rub, which contains emollients, the correct use of the hand rub and a clear guideline when to disinfect and wash hands in the clinical setting. Common mistakes in the use of alcohol-based hand rubs are application to pre-irritated skin and washing hands before hand disinfection, which is, in general, not necessary, or after hand disinfection, which results in washing off the emollients. Clear preparation and guidance of healthcare workers before the introduction of alcohol-based hand rubs can help to enhance compliance in hand hygiene. The switch from handwash to alcohol-based hand rub will improve healthcare workers skin if mistakes are avoided and hand rinses are used correctly.

Alcohols↗

PubMed2003

Profile of irritant patch testing with detergents: sodium lauryl sulfate, sodium laureth sulfate and alkyl polyglucoside.

The cutaneous reaction to detergents follows distinct kinetic rules: the duration of application and the irritant concentration are of major importance. The aim of this study was to evaluate the differences in kinetics of skin reaction between the standard irritant sodium lauryl sulfate (SLS), and 2 modern detergents: sodium laureth sulfate (SLES) and alkyl polyglucoside (APG). We performed patch testing with SLS and SLES (or APG) at different concentrations (0.125, 0.25, 0.5, 1.0 and 2.0%) and with different exposure times (6, 12 and 24 h). Evaluation was conducted by measurement of transepidermal water loss (TEWL) and laser Doppler flowmetry (LD) 24 h, 7 and 10 days after patch removal. We found a pronounced reaction to SLS, and a far milder one to SLES. Even at the highest concentration the skin reaction to APG was hard to detect. During the regeneration period (day 3-10) SLS showed even at day 10 an increased TEWL at all concentrations tested. The irritation due to SLES was convincingly detectable only up to day 7, whereas the APG-tested skin areas showed no significant reaction even at day 3. These results demonstrate the improvement in reduction of skin irritation achieved by development of novel detergents.

Adolescent↗

PubMed2003

Randomized comparison of interferon alpha and hydroxyurea with hydroxyurea monotherapy in chronic myeloid leukemia (CML-study II): prolongation of survival by the combination of interferon alpha and hydroxyurea.

The optimum treatment conditions of interferon (IFN) alpha therapy in chronic myeloid leukemia (CML) are still controversial. To evaluate the role of hydroxyurea (HU) for the outcome of IFN therapy, we conducted a randomized trial to compare the combination of IFN and HU vs HU monotherapy (CML-study II). From February 1991 to December 1994, 376 patients with newly diagnosed CML in chronic phase were randomized. In all, 340 patients were Ph/BCR-ABL positive and evaluable. Randomization was unbalanced 1:2 in favor of the combination therapy, since study conditions were identical to the previous CML-study I and it had been planned in advance to add the HU patients of study I (n=194) to the HU control group. Therefore, a total of 534 patients were evaluable (226 patients with IFN/HU and 308 patients with HU). Analyses were according to intention-to-treat. Median observation time of nontransplanted living patients was 7.6 years (7.9 years for IFN/HU and 7.3 years for HU). The risk profile (new CML score) was available for 532 patients: 200 patients (38%) were low, 239 patients (45%) intermediate, and 93 patients (17%) high risk. Complete hematologic response rates were higher in IFN/HU-treated patients (59 vs 32%). Of 169 evaluable IFN/HU-treated patients (75%), 104 patients (62%) achieved a cytogenetic response that was complete in 12% (n=21), major in 14% (n=24), and at least minimal in 35% (n=59). Of the 534 patients, 105 (20%) underwent allogeneic stem cell transplantation in first chronic phase. In the low-risk group, 65 of 200 patients were transplanted (33%), 30 (13%) in the intermediate-risk group, and nine (10%) in the high-risk group. Duration of chronic phase was 55 months for IFN/HU and 41 months for HU (P<0.0001). Median survival was 64 months for IFN/HU and 53 months for HU-treated patients (P=0.0063). We conclude that IFN in combination with HU achieves a significant long-term survival advantage over HU monotherapy. In view of the data of CML-study I, these results suggest that IFN/HU is also superior to IFN alone. HU should be combined with IFN in IFN-based therapies and for comparisons with new therapies.

Adolescent↗

PubMed2003

Chronic myeloid leukemia in the elderly: long-term results from randomized trials with interferon alpha.

Chronic myeloid leukemia (CML) in older patients has not been studied well. To assess the long-term outcome of older patients with Philadelphia- and/or BCR-ABL-positive CML, 199 patients aged >/=60 years representing 23% of 856 patients enrolled in the German randomized CML-studies I (interferon alpha (IFN) vs hydroxyurea (HU) vs busulfan (BU) and II (IFN+HU vs HU alone) were analyzed after a median observation time of 7 years. In all, 45 patients were treated with Bu, 63 with HU, and 91 with IFN. The 5-year survival was 38% in patients >/=60 years and 47% in patients <60 years (P<0.001). Whereas 5-year survival in chemotherapy-treated older patients was inferior to that in younger patients (33 vs 46%, P=0.006 for HU and 29 vs 38%, P=0.042 for Bu), no significant survival difference could be verified in IFN-treated patients (46 vs 53%, P=0.077). Calculation of age-adjusted, relative survival confirmed these results. Adverse effects of IFN were similar in both age groups, but IFN dosage to achieve treatment goals was lower in older patients. We conclude that the course of CML is not different in the elderly. They require lower IFN doses, achieve the same hematologic and cytogenetic response rates and the same survival advantage at comparable toxicity.

Adolescent↗

PubMed2003

Effects of skin occlusion in patch testing with sodium lauryl sulphate.

BACKGROUND: When evaluating transepidermal water loss (TEWL) in patch testing, the occlusive effect of the patch must be considered as an important artificial impairment of the measurement. OBJECTIVES: To investigate the time course of effects of occlusion. METHODS: Epicutaneous patches with sodium lauryl sulphate (SLS) 0.25%, SLS 0.5%, water and an empty test chamber (control) were applied on the volar forearm for different time intervals (12, 24, 48 h). Test reactions were evaluated by measurement of TEWL immediately, every 15 min during the first hour, every 30 min during the following 3 h and 24 h after patch removal. RESULTS: After patch removal, TEWL values showed a steep increase. When compared with basal values, TEWL values after SLS patch testing remained increased for 24 h, whereas TEWL values on water patch sites were only significantly increased for up to 180 min, and on empty patch sites for only up to 120 min after patch removal. The prolonged increase in TEWL values in SLS patch testing seemed to be induced by barrier function damage caused by SLS itself, as shown in various earlier studies. After the initial increase, TEWL values showed a significant decrease for all patches from 0 to 120 min after patch removal. Patch testing with water gave a significant decrease in TEWL values up to 180 min, and for empty chambers (control) up to 150 min after removal of patches. These data suggest that the occlusive effect on TEWL in patch testing ends 3 h after the removal of test chambers. CONCLUSIONS: We recommend TEWL measurement in SLS patch testing after a period of at least 3 h after patch removal. For practical purposes a 24-h period after patch removal may be useful.

Adolescent↗

PubMed2002

Long-term assessment of the wet precipitation chemistry in Austria (1984-1999).

The aim of the present study was to determine the long-time trends in concentrations and depositions of major ions in wet precipitation samples collected at 11 sampling sites from the Austrian precipitation chemistry network in the period 1984-1999. The analytical results were treated by the use of least square linear regression method. It is shown that a serious decrease of sulfate (between 30% and 60% for the period) and hydrogen ion (between 60% and 102% for the period) concentrations and depositions is achieved at almost all sampling sites and in most of these cases the linear trend proves to be statistically significant. Nitrogen containing ions and base cations do not reveal a distinct trend of changing and in the majority of the sites the linear models are not adequate. In principle, an overall slight concentration and deposition decrease for these major ions is observed (up to 30% for the period of observation) but some substantial exceptions are also found (site Haunsberg or site Lobau). The changes in chloride concentration and deposition, too, do not indicate significant linear trend and, in general, are decreasing for the period of monitoring. In order to give some explanation of the exceptional behaviour of some of the major ions in several sites, an additional comparison with Austrian emission data (sulfur dioxide, nitrogen oxides, ammonium) and with data from five EMEP sites from neighbouring countries is performed. A significant West-East trend of acidity increase is found as well as a good correlation with the emission trends. Therefore, both transboundary and specific local factors could be substantial factors in the wet precipitation chemistry in the region.

Austria↗

PubMed2002

The influence of body mass index on skin susceptibility to sodium lauryl sulphate.

BACKGROUND: The influence of nutrition on the physiological functions of man is well studied. Numerous diseases can be exacerbated by obesity. However, it has not yet been determined whether body weight and body mass index (BMI), as an indicator of a high body fat store, can influence skin sensitivity. OBJECTIVE: This study investigates the correlation between body mass index and the epidermal functions, evaluated by bioengineering methods, before and after an irritant patch test with sodium lauryl sulphate (SLS). METHODS: Epidermal functions were evaluated using an evaporimeter, chromameter and laser-Doppler-flowmeter. Patch testing was conducted for 48 h with two different concentrations of SLS (0.25% and 0.5%) on the forearms of healthy volunteers. Measurements were performed 24h after patch removal. RESULTS: Obese individuals showed significantly increased transepidermal water loss (TEWL), skin blood flow and skin colour (red) as compared to a control group. However, the degree of skin sensitivity to SLS was not correlated with BMI. CONCLUSION: Basal biophysical parameters of the skin are primarily correlated with the BMI. This may be caused by obesity-induced physiological changes, e.g. increased sweat gland activity, high blood pressure and physiological temperature-regulating system. The epidermal barrier function, as evaluated after SLS patch testing is, however, not correlated with a high BMI, indicating a normal skin barrier.

Adolescent↗

PubMed2002

Differences of skin irritation between Japanese and European women.

BACKGROUND: After using cosmetics, Japanese women frequently complain about sensitive, stinging skin. We wondered whether Japanese women's skin is more sensitive than that of Caucasians. OBJECTIVES: To examine possible racial differences of skin irritation and subjective sensations. METHODS: We performed patch testing on the forearm with sodium lauryl sulphate (SLS) at different concentrations (0.25%, 0.5%) and 24-h exposure time. Skin reaction was evaluated by measurement of transepidermal water loss (TEWL), stratum corneum hydration, sebum secretion, laser Doppler flowmetry (LD), content of melanin and erythema. During a stinging test with 10% lactic acid (applied to one side of the cheeks) the subjects were asked to describe the present intensity of any sensation. We used a Chromameter to measure skin colour before and after application of lactic acid. This study was performed in Marburg, Germany, with healthy Japanese and German women living in Marburg. RESULTS: After SLS testing, we found no significant differences of the barrier function in the stratum corneum, but we found significant subjective sensory differences between Japanese and German women. CONCLUSIONS: Japanese women may complain about stronger sensations reflecting a different cultural behaviour rather than measurable differences in skin physiology; however, a faster penetration of SLS in Japanese cannot be excluded.

Adult↗

PubMed2002

Changes in skin physiology during bath PUVA therapy.

BACKGROUND: Frequent bathing leads to a skin barrier damage with various changes in physiological skin parameters. Conversely, ultraviolet (UV) irradiation may improve the impaired skin barrier by reducing inflammatory reactions. OBJECTIVES: The aim of this study was to investigate the changes of physiological skin parameters during a therapy with 8-methoxypsoralen (8-MOP) bathing and subsequent UVA irradiation. METHODS: Thirty patients with a skin disease without barrier disruption were treated with daily bathing in a 8-MOP solution (0.0005%) and subsequent UVA irradiation. Multiple physiological skin parameters (transepidermal water loss, skin blood flow, skin colour, sebum content, skin hydration) were measured repeatedly on clinically non-affected skin on the back, forearm and forehead. In addition, patch testing with sodium lauryl sulphate (SLS) (0.5%) was performed on the forearm and on the back. RESULTS: We found a moderate but significant disturbance of skin barrier and hydration on the forearm and the back (bathing + irradiation) after increasing dosages of therapy. In addition, SLS testing leads to stronger reactions. CONCLUSIONS: We conclude that on clinically healthy skin the impairment of skin barrier by frequent bathing cannot be completely compensated by subsequent UVA irradiation. When conducting a treatment with 8-MOP bathing and UVA irradiation a concomitant therapy supporting the recovery of skin barrier, e.g. with moisturizer, should be performed.

Adult↗