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Biomedical subjects

H C Korting

Publications and source records attributed to H C Korting.

At least 91 records · Page 5Linked to original sources
PubMed1995

The concept of the acid mantle of the skin: its relevance for the choice of skin cleansers.

Whereas soap has long been the only cleansing agent, a new generation of cleansers, the so-called synthetic detergents or syndets, has been developed during the last decades. They offer a wide variety of formulations and are therefore becoming more and more important for cleansing of diseased and healthy skin. Among the syndets, especially those with a pH of about 5.5 seem to be relevant. In contrast to alkaline soap, they do not interfere with the cutaneous microflora, whose composition is linked to the skin surface pH. As their irritancy potential might be even lower than that of soap, the benefit-to-risk ratio of syndets appears favorable.

Acids↗
PubMed1995

Tolerance to different toilet paper preparations: toxicological and allergological aspects.

BACKGROUND AND DESIGN: A controlled open trial was performed in 40 individuals suffering from chronic perianal eczema. Various toilet paper preparations representing the conventional type made of pure cellulose, the recycled and the moist type were investigated using the patch test as were allergens possibly related to toilet paper. In addition, a chronic use test and a repeated rubbing test were performed with a conventional and a recycled toilet paper preparation. RESULTS: A total of 20 patients could be evaluated in full. A variety of reactions were seen in the patch test, most of which were of the allergic type. Allergens included many different chemical entities, e.g. preservatives used in moist toilet paper such as Kathon CG and Euxyl K 400. In a volunteer allergic to Euxyl K 400, allergy to the moist toilet paper regularly used by him was established. After discontinuation of its application, perianal dermatitis disappeared. In the repeated rubbing test at the forearm, 10 volunteers showed a reaction with the recycled paper preparation while no such reaction was seen upon the application of the conventional type of toilet paper. The validity of these findings was corroborated by corresponding results in the use test. CONCLUSION: There is clearly a potential for allergic reactions to components of moist toilet paper and reactions to recycled toilet paper presumably irritant by nature. These irritant reactions are probably caused by the rough texture of current paper types and do not reflect the presence of potentially toxic ingredients such as metal salts.

Adult↗
PubMed1995

The influence of the pH-value on the growth of Brevibacterium epidermidis in continuous culture.

Brevibacterium epidermidis is a major component of the bacterial flora of certain skin surface biotopes, characterized by a comparatively high pH-value. The presence of Brevibacterium epidermidis seems to be linked to the production of malodour. Skin surface pH has been found to be a major factor of bacterial growth on the skin. In order to find out if this might also apply to Brevibacterium epidermidis, this microorganism was grown in vitro in continuous culture using a chemostat. Specific growth rate and density of colony forming units were well correlated. While the organism grew readily from pH 5.5 to 8.5, this was not the case with a pH of 5.0. Thus pH-shifts induced by cosmetic procedures can only prevent unpleasant body odour due to abundant growth of bacteria if the pH-value is decreased to 5.0 or less.

Brevibacterium↗
PubMed1995

In vivo assessment of the atrophogenic potency of mometasone furoate, a newly developed chlorinated potent topical glucocorticoid as compared to other topical glucocorticoids old and new.

Topical glucocorticoids still belong to the most important medications available in dermatotherapy. The clinical use of topical glucocorticoids, however, nowadays is limited by the fear of side-effects both systemic and local, especially skin atrophy. The purpose of this study was to assess the atrophogenicity potential of newly developed topical glucocorticoids which were said to show an increased benefit-risk ratio. The test preparations comprised mometasone furoate, the corresponding vehicle, prednicarbate and hydrocortisone. They were applied once or twice daily for 6 weeks in healthy volunteers. Skin thickness was assessed weekly by using high frequency pulsed ultrasound. Clinically, none of the volunteers showed any sign of overt skin atrophy. Skin thickness, however, was reduced to a certain extent with all trial preparations including the base preparation. As to be expected from previous experiments the results for hydrocortisone and prednicarbate did not differ significantly from the ones for the base preparation. Interestingly, the same applied to mometasone furoate. These findings, together with the other available data, give evidence of an increased benefit-risk ratio as compared to previous medium potent topical glucocorticoids. This might be of particular interest facing psoriasis vulgaris where an antiproliferative activity of a drug is needed.

Administration, Topical↗
PubMed1994

[The interdisciplinary aspects of notalgia paraesthetica].

For 3 years a 75-year-old man with type II diabetes had been suffering from paroxysmal pruritus in a circumscribed area of brown discoloration of the skin over the left should blade. This condition, also known as notalgia paraesthetica, is a rare, but perhaps underdiagnosed, neurocutaneous entity, a largely sensory neuropathy due to a muscular compression phenomenon. In this case histological examination of a biopsy specimen showed focal acanthosis, obvious basal hyperpigmentation and discrete perivascular lymphocytic infiltration with numerous melanophages. At first, glucocorticoids were administered unsuccessfully against the distressing pruritus. Purely symptomatic local capsaicin treatment decreased the pruritus temporarily. Endocrinological diagnosis failed to demonstrate multiple endocrine neoplasia (MEN) syndrome 2A, which has been frequently described in association with notalgia paraesthetica.

Aged↗
PubMed1994

Liposomal tretinoin for uncomplicated acne vulgaris.

Frequently occurring skin irritancy and flare-up reactions impede the use of topical tretinoin for acne vulgaris due to poor patient compliance. Liposome encapsulation improves penetration into the skin and local tolerability in animals. We investigated efficacy and local tolerability of liposomal tretinoin in man. In a double-blind study 20 patients with uncomplicated acne vulgaris received liposomal tretinoin (0.01%) on one side of the body and a commercial gel preparation with either 0.025% or 0.05% on the other once daily for 10 weeks. Comedones and papules/pustules were counted every 2 (-4) weeks. Then also redness, scaling, and burning were rated according to a four-point scale. Moreover, the patients noted skin irritancy in a diary on a daily base. With conventional tretinoin the gels were equally efficacious and equally well tolerated. Liposomal tretinoin also appeared equipotent to the reference gels. There may even have been a slightly more rapid clearing of comedones following the liposome preparation. With respect to skin irritancy, however, liposomal tretinoin was superior. As rated by the patients, liposome encapsulated tretinoin induced less burning (mean cumulative score 2.7 +/- 1.2) than the 0.025% gel (16.1 +/- 7.1) and the 0.05% gel (9.7 +/- 4.1) gel and less erythema (1.8 +/- 0.7) than the 0.025% gel (11.4 +/- 3.8; (P < 0.05). Liposomal tretinoin was also better tolerated according to the rating by the investigator. Liposomal encapsulation of tretinoin allows reduction of the concentration of the active agent without a decline in efficacy for acne vulgaris. Since local tolerability is thus increased, liposomal tretinoin should favor the acceptance of this treatment by the patient.

Acne Vulgaris↗
PubMed1994

[The immotile cilia syndrome. A rare form of male infertility].

A man presented with 100% immotile spermatozoa. Transmission electron microscopy showed the absence of both central tubules in all sperm tails; the nine peripheral tubules, dynein arms, radial spokes and other structures of the sperm tail were normal. Immotile cilia syndrome of the 9 + 0 tubular pattern was diagnosed. Other anomalies frequently associated with immotile cilia syndrome, such as recurrent airway infections, bronchiectases and situs inversus (Kartagener's syndrome), were not present in this case.

Adult↗
PubMed1994

MTT-assay and neutral red release (NRR)-assay: relative role in the prediction of the irritancy potential of surfactants.

A comparative study on the in vitro and in vivo irritancy of anionic, amphoteric and non-ionic surfactants was performed. In vitro ED50 values of the surfactants were determined by two cytotoxicity assays, the dimethylthiazoldiphenyltetrazoliumbromide (MTT) assay and the neutral red release (NRR) assay on serum-free cultured human foreskin keratinocytes. In vivo human irritancy data were obtained by a 24 hour occlusive patch test in volunteers and the irritant skin response quantified by visual scoring, evaporimetry and colorimetry. A close relationship between the evaluation methods of the patch test was observed (r = 0.92 to r = 0.96), confirming that the 'bioengineering' methods, such as evaporimetry and colorimetry are suitable for measuring skin irritation. For six surfactants evaluated we found a good correlation (r = 0.91) between the ED50 values of the MTT assay and the in vivo irritancy data. The NRR assay yielded less satisfactory correlation coefficients with regard to MTT assay (r = 0.42) and in vivo irritancy data (r = 0.46). This can be mainly attributed to a misinterpretation of the amphoteric and non-ionic surfactants by the NRR assay. While the NRR assay may better evaluate the anionic surfactants, the MTT assay seems to be more suitable when testing a broader range of chemically diverse surfactants. Limitations of cell culture systems are noted, although the potential usefulness of cultured human skin cells for skin irritancy testing has been clearly demonstrated.

Adult↗
PubMed1994

Discrimination of the irritancy potential of surfactants in vitro by two cytotoxicity assays using normal human keratinocytes, HaCaT cells and 3T3 mouse fibroblasts: correlation with in vivo data from a soap chamber assay.

Cell cultures have been proposed as a promising model for local tolerance testing. This study evaluated the cytotoxic effects of surfactants on early passage normal human keratinocytes, transformed human keratinocytes (HaCaT cells) and Swiss 3T3 embryonic mouse fibroblasts. Cell membrane integrity, as assessed by the release of the vital dye neutral red, and cell proliferation, as assessed by measurement of the total protein content, were both affected in a dose-dependent manner in response to surfactant exposure. There was a close correlation between the dose-response characteristics for the three cell types. Two surfactants exhibited differential effects on membrane integrity and proliferation, and thus no significant correlation was found between the two endpoints. The irritation potential of the surfactants to human forearm skin in vivo was assessed in a soap chamber test using transepidermal water loss and skin redness as quantitative endpoints. A comparison between the responses in vivo and in vitro yielded the highest correlation for the neutral red release test on normal keratinocytes. The total protein test did not significantly correlate with the soap chamber assay for keratinocytes and HaCaT cells. These results suggest that cultured normal human keratinocytes may be predictive for the irritancy of various surfactants in man. Definite judgement, however, has still to be based on confirmation in human volunteers of larger groups of compounds with diverse physico-chemical properties.

3T3 Cells↗
PubMed1994

Successful treatment of hydroxyethyl starch-induced pruritus with topical capsaicin.

We report a case of recalcitrant pruritus after infusion therapy with hydroxyethyl starch (HES) for sudden deafness. The diagnosis was confirmed by detection of typical HES storage vacuoles within dermal macrophages and perineural cells. Treatment with antihistamines and antipruritic agents, UVB irradiation, and neuroleptic drugs, was ineffective. Topical capsaicin (0.05%) twice daily produced excellent symptomatic relief, without side-effects.

Administration, Topical↗
PubMed1994

Differential effect of medium potent nonhalogenated double-ester-type and conventional glucocorticoids on proliferation and chemotaxis of fibroblasts in vitro.

Recently several attempts have been made to develop glucocorticoids which show less pronounced side effects. We intended, therefore, to use experimental systems to examine the influence of newly developed nonhalogenated glucocorticoids and conventional fluorinated congeners, demonstrating similar anti-inflammatory activity in vivo, on biosynthetic capacities of human fibroblasts. Fibroblasts were kept in monolayer cultures and exposed to different concentrations of the active compounds for 6 days to analyze the influence on proliferation. Chemotaxis of fibroblasts was studied in blind well Boyden chambers. Fibroblast-conditioned medium was used as chemoattractant. All glucocorticoids tested influenced fibroblast proliferation at high (10(-5) M) and low (10(-9) M) concentration. Yet the effect was clearly more marked with fluorinated compounds. Basically, the same applied for chemotaxis. At the low concentration, however, nonfluorinated glucocorticoids exerted almost no influence. These results suggest that modifications of steroidal structure can specifically influence their effects on biosynthetic capacities of fibroblasts.

Adult↗
PubMed1994

Unusual coexistence of systemic lupus erythematosus and primary biliary cirrhosis.

Systemic lupus erythematosus (SLE) and primary biliary cirrhosis (PBC) are distinct clinical disorders which rarely occur in the same patient. We report on a 65-year-old woman with coexistence of both conditions. Diagnosis of SLE was ascertained by the presence of seven ACR criteria (cutaneous lesions, photosensitivity, antinuclear and anti-double-stranded-DNA antibodies, pancytopenia, arthritis, oral lesions). PBC was disclosed by clinical investigation, liver histology and highly positive antimitochondrial M2 antibodies. The most important differential diagnoses of lupus hepatitis are PBC and autoimmune hepatitis. Diagnostic criteria for these conditions are discussed, and previous reports on overlap between SLE and PBC are reviewed.

Aged↗
PubMed1994

Liposomes: a drug carrier system for topical treatment in dermatology.

During the last three decades, the value of liposomes as a drug delivery system has been examined. The interest in liposomes as carriers of active substances is based on their potential to enclose various types of biological materials and to deliver them to diverse cell types. Whereas experiments with systemically applied liposome-entrapped drugs often proved disappointing, recent work suggests that liposomes as vehicles for topical drug delivery may be superior to conventional preparations. The use of liposomes in ophthalmology for the diagnosis and treatment of different ocular diseases has been postulated recently. Dermatics based on liposomes as drug carrier systems have been tested for different types of ingredients, e.g., corticosteroids and local anesthetics. To understand more about the pharmacological potential of liposomes, it is important to investigate the interaction between liposomes and the epidermis. Analysis in this field suggests that only a compromised epidermal barrier enables intact liposomes to penetrate the skin. This is in accordance with clinical findings. A liposomal preparation of betamethasone dipropionate seems superior to a conventional commercial preparation in eczema but not in psoriasis vulgaris. However, one cannot rule out the follicular pathway as an alternate route. Many questions must be resolved before a complete understanding of liposomes as a drug carrier system in dermatology can be reached. However, examinations performed so far indicate that liposomes might be useful as vehicles for topical drug delivery in various diseases of the skin.

Administration, Topical↗
PubMed1993

Erythema induratum of Bazin. Evidence of T-lymphocyte hyperresponsiveness to purified protein derivative of tuberculin: report of two cases and treatment.

BACKGROUND AND DESIGN: Erythema induratum of Bazin, a chronic form of nodular vasculitis, may be associated with chronic infections by Mycobacterium tuberculosis. However, the true origin of the disease is a subject of speculation and remains elusive. Two female patients (58 years old and 33 years old) with a minimum 10-year history of chronic tender ulcerating nodules on the lower aspects of the legs were studied both clinically and in the response of their peripheral T cells to purified protein derivative of tuberculin. RESULTS: Both patients with no previous history of tuberculosis had strongly positive skin test results at a Mantoux 10(-4) dilution (1 unit of purified protein derivative). In response to full-course triple-agent (isoniazid, rifampicin, and ethambutol) chemotherapy, a complete remission of clinical symptoms was seen in both cases and no relapse occurred after discontinuation of therapy. A marked increase in peripheral T-lymphocyte response to purified protein derivative was found before onset of and during successful therapy. CONCLUSIONS: The present clinical observations together with the pronounced cellular response to purified protein derivative suggest a tuberculous origin of erythema induratum of Bazin.

Adult↗
PubMed1993

Influence of topical erythromycin preparations for acne vulgaris on skin surface pH.

Topical erythromycin is a standard regimen for inflammatory acne vulgaris because of its action against Propionibacterium acnes. Changes in P. acnes colonization are inducible by long-lasting changes of skin surface pH. Therefore, the influence of six erythromycin preparations with approximative pH values of 7.5 (preparation A) to 10.2 (C) on the skin surface pH was evaluated in healthy volunteers using a cross-over design. Following a 14-day run-in period, a constant skin surface pH (5.0) was found. Ten subjects received single doses 2-3 days apart; 20 volunteers applied preparations A and C for 28 days. Single doses of preparations A and E (pH 8.0) increased skin pH to 6.99 and 8.61, respectively, at 15 min; it then gradually declined. The other preparations induced only a minor rise of short duration. At the end of the long-term application, the skin surface pH amounted to 5.73 (A) and 5.39 (C). There was no correlation between the effect on skin surface pH and the approximative pH of the preparations. A close relation of single-dose and long term-effects was observed, however. The skin surface pH during the application of preparation A is high enough to increase P. acnes growth about fourfold as compared with normal skin and thus may counteract the antibacterial effect. Clinical relevance should be evaluated in a controlled clinical trial comparing the efficacy of preparation A with that of preparation C.

Acne Vulgaris↗
PubMed1993

Liposomes for atopic dry skin: the rationale for a promising approach.

Atopic dry skin characterized by a defect of the barrier function as determined by transepidermal water-loss measurements at the ultrastructural level shows an increase in membrane-coating granules (MCGs). MCGs are lamellar, ovoid organelles appearing in the stratum spinosum and stratum granulosum. MCGs consist of stacks of small parallel disks that are extruded and fuse to continuous lamellae. Liposomes, i.e., unior multilamellar vesicles composed of alternating lipid and water phases are structurally similar. Moreover, they also can form continuous lamellae. While phospholipids are generally used for liposome production, skin lipids and in particular ceramides can also be used. These lipids also seem to be the major components of MCGs. Hence, it seems advisable to use liposomes made of such lipids in the treatment of atopic dry skin. Apart from the probable inherent effect liposomes of this type may also apply particularly well for the delivery of active components.

Body Water↗
PubMed1993

Anti-inflammatory activity of hamamelis distillate applied topically to the skin. Influence of vehicle and dose.

The anti-inflammatory activity of hamamelis distillate has been evaluated with respect to drug concentration (0.64 mg/2.56 mg hamamelis ketone/100 g) and the effect of the vehicle (O/W emulsion with/without phosphatidylcholine (PC) in an experimental study. The effects were compared with those of chamomile cream, hydrocortisone 1% cream and 4 base preparations. Erythema was induced by UV irradiation and cellophane tape stripping of the horny layer in 24 healthy subjects per test. Skin blanching was quantified by visual scoring and chromametry. Drug effects were compared with one another and with an untreated control area, as well as with any action due to the vehicle. UV-induced erythema at 24 h was suppressed by low dose hamamelis PC-cream and hydrocortisone cream. Hydrocortisone appeared superior to both hamamelis vehicles, hamamelis cream (without PC) and chamomile cream. The latter preparation was also less potent than hamamelis PC-cream. Erythema 4 to 8 h after the stripping of the horny layer was suppressed by hydrocortisone (P < or = 0.05). Inflammation was also less pronounced following low dose hamamelis PC-cream and chamomile cream. Hamamelis PC-cream, however, appeared less potent than hydrocortisone. In general, visual scoring was more discriminatory than chromametry. The results have demonstrated an anti-inflammatory activity of hamamelis distillate in a PC-containing vehicle. A fourfold increase of drug concentration, however, did not produce an increase in activity.

Administration, Topical↗