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PubMed1978

The chemoattractant properties of comedonal components.

Acculation of clusters of polymorphonuclear leukocytes (PMN) along the periphery of the walls of comedones (predominantly of the closed variety), has been described as the first change marking the transition of quiescent, noninflamed lesions in acne, into inflammatory ones. The present study analyzed the chemoattractant properties of different comedonal components for human PMN in an effort to evaluate the potential significance of these substances in stimulating the chemotactic response of PMN in the initial phases of inflammatory acne. It was found that the lipids extracted from pooled comedones had chemotactic activity for PMN in vitro. Beyond that, all chemotactic activity in comedones was related to bacteria. Propionibacterium acnes produced low molecular weight, dialyzable, heat stable chemotactic factors which were released into culture medium during bacterial growth. In addition to the extracellular cytotaxins, P. acnes whole cells and other extracellular products were strong cytotaxigens and activated heat labile chemotactic factors in human and guinea pig serum.

Acne Vulgaris↗
PubMed2005

A simple open comedone extraction technique for Favre-Racouchot disease.

Favre-Racouchot disease (FRD) is a common disease characterized by solar elastosis and large open comedones and cysts. This disorder mainly affects elderly Caucasian men who have had a great deal of exposure to the sun. Patients having FRD continuously develop numerous large open comedones that could cause a cosmetic problem. We performed a simple and effective extraction technique for these open comedones using a standard dissecting forceps. This technique is well tolerated and no complications were observed. We suggest this comedone extraction technique as a simple alternative treatment for this common cosmetic problem.

Aged↗
PubMed1979

Complement activation in acne vulgaris: consumption of complement by comedones.

Comedones, the contents of acne lesions, were shown to consume scomplement hemolytic activity in normal serum. This consumption was stimulated by the addition of serum from patients with inflammatory acne. Absorption of acne serum with Propionibacterium acnes cells removed all stimulating activity. Immunoelectrophoretic analysis of serum incubated with comedones revealed the conversion of C3 and factor B in normal serum. The addition of acne serum resulted in cleavage of C4. In serum treated with ethylene glycol-bis(beta-aminoethyl ether)-N,N'-tetraacetic acid, only C3 and factor B were converted. This indicates that comedones may activate complement by either the classical or the alternative pathway. It is suggested that P. acnes cells in comedonal material are responsible for the complement activation.

Acne Vulgaris↗
PubMed1993

Treatment of closed comedones--comparisons of fulguration with topical tretinoin and electrocautery with fulguration.

Two consecutive studies were performed with the aim of clearly defining the optimal physical treatment for closed comedones. The first 10 patients with clinically significant numbers of facial comedones were treated with fulguration under EMLA anaesthesia on one side of the face and topical tretinoin on the opposite side. At the end of the study fulguration was shown to be significantly (p = 0.005) superior to topical tretinoin. A direct comparison of light electrocautery using EMLA anaesthetic with fulguration without anaesthesia was then performed on 12 patients. The comedones were subdivided by size into those that were approximately 1 mm or less in diameter and those of greater dimensions. In the treatment of larger comedones electrocautery was shown to be significantly superior to fulguration (p = 0.025), but there was no significant difference in the efficacy of the treatments for the smaller lesions.

Acne Vulgaris↗
PubMed1994

[A case of unilateral elastosis with cysts and comedones. Favre-Racouchot syndrome].

INTRODUCTION: Cutaneous elastosis with cysts and comedones (Favre-Racouchot) is one of the oldest known manifestations of helioderma. Both sides of the face are usually involved symmetrically. CASE REPORT: We observed a 65-year-old woman with extremely severe Favre-Racouchot disease localized exclusively on the left side of the face. The diagnosis of elastosis with cysts and comedones was confirmed histologically. This elastosis with cysts and comedones was associated with spasms of the hemiface treated with injections of botulinic toxin. This association was fortuitous and we retained actinic irradiation as the causal agent in this woman who had worked for 15 years in the same room. The elastosis occurred on the side of the face which had been continuously exposed at the same orientation to the window. COMMENTS: This original observation is similar to cases where facial exposure to artificial light or sunlight is asymmetrical, leading to a higher incidence of lesions on one side of the face: colloid milium, actinic keratosis, Dubreuilh melanoma (malignant lentigo) or simple helioderma. The asymmetrical nature of the actinic lesions is often related to automobile driving. This case was particular since it demonstrated that Favre-Racouchot elastosis with cysts and comedones is due to actinic irradiation and not to skin aging.

Acne Vulgaris↗
PubMed1991

Effects of subminimal inhibitory concentrations of minocycline on neutrophil chemotactic factor production in comedonal bacteria, neutrophil phagocytosis and oxygen metabolism.

Comedonal bacteria, Propionibacterium acnes, P. granulosum and coagulase-negative staphylococci (CNS) seem to play an important initiating role in the inflammatory process by producing neutrophil chemotactic factors. The attracted neutrophils, after phagocytosis, release inflammatory factors such as reactive oxygen species (ROS). We investigated the effects of minocycline at subminimal inhibitory concentrations (sub-MIC), i.e. one-tenth MIC, on the production of human neutrophil chemotactic factors in comedonal bacteria, and on several inflammatory parameters of neutrophils, including neutrophil phagocytosis and generation of ROS (O2-, H2O2, OH.). ROS generation in a cell-free, xanthine-xanthine oxidase system was also assessed. Production of neutrophil chemotactic factors in all strains of P. acnes, P. granulosum and CNS were significantly suppressed by sub-MIC minocycline. Sub-MIC minocycline effectively reduced three kinds of neutrophil-generated ROS (O2-, H2O2, OH.). However, neutrophil phagocytosis and the ROS generated in a cell-free system were not markedly changed in the presence of sub-MIC minocycline. The results suggest that sub-MIC minocycline has an anti-inflammatory effect by inhibiting the production of neutrophil chemotactic factors in comedonal bacteria as well as ROS generated by neutrophils in the inflammatory process of acne.

Acne Vulgaris↗
PubMed2001

[Familial dyskeratotic comedones. A rare entity].

Familial dyskeratotic comedones is a rare autosomal dominant genodermatosis. In childhood or adolescence disseminated keratotic papules develop and gradually increase in number with time. The isolated papules show a central keratotic plug which tends to recur after extraction. Pruritus and occasional inflammation are the only symptoms. The lesions appear on the extremities, and less frequently on the trunk and the face. About half of the patients have a history of acne vulgaris. The histologic picture is highly characteristic and shows a deep invagination of an acantholytic and dyskeratotic epidermis with prominent cornification. Familial dyskeratotic comedones are generally refractory to any therapy. We report on two sisters with familial dyskeratotic comedones successfully treated by CO2-laser therapy.

Adult↗
PubMed1981

A comparison of comedonal and skin surface lipids from hairless dogs showing clinical signs of acne.

Certain animals in a colony of hairless dogs (Mexican Hairless x Beagle) display the clinical features of acne vulgaris, including both open and "closed" comedones, milia, pustules, and abscesses. In order to compare the canine disease with human acne, lipids from the various types of noninflamed lesions and from the skin surface were analyzed by thin-layer (TLC) and gas-liquid (GLC) chromatography. TLC of total nonhydrolyzed lipid from comedones and milia gave similar patterns, with free sterol, ceramides, and free fatty acids comprising the bulk of the material and sterol esters and wax diesters as minor components. Skin surface samples contained mainly sterol esters and wax diesters, with smaller amounts of free sterol and only trace amounts of ceramides. GLC analysis of total hydrolyzed fatty acids from comedones showed similar patterns for the various lesions types, with 22 to 26 carbon acids comprising 55-65% of the total; these acids comprised only 19% of the total hydrolyzed skin surface samples. Analyses by argentation TLC and GLC/mass spectrometry showed the lesional lipids contained significant amounts of alpha-hydroxy-16:0, 16:1, 18:1 and 18:2, but only trace amounts of these appeared in the surface lipid. Fatty acid analysis of individual lipid classes show that the long chain, saturated fatty acids occur predominantly in the free fatty acid and polar lipid fractions and not in the wax diester of sterol ester fractions. Since wax diesters and sterol esters are products of sebaceous gland lipid synthesis, whereas free sterols, fatty acids, and ceramides are characteristic epidermal lipids, the data indicate that the lipids obtained from the acne lesions of dogs are primarily epidermal in origin and that sebaceous gland contribution is minimal in plugged follicles.

Acne Vulgaris↗
PubMed1978

Ultrastructural basis for the assay of topical acne treatments. Transmission and scanning electron microscopy of untreated comedones.

After two decades of using systemic antibiotics as a main treatment for acne, emphasis is again being placed on topical agents. Thus, it is highly desirable to have a procedure whereby the activity of the various compounds can be evaluated by direct visualization. Scanning electron microscopy combined with transmission electron microscopy provide the tools for such in assay. This study describes the ultrastructure of untreated comedones and provides the baseline or control data necessary for testing topical treatments. Comedones obtained by punch biopsies or comedo extractors were processed for electron microscopy and studied with an ETEC Autoscan Scanning Electron Microscope and with Philips EM 300 and EM 301 Transmission Electron Microscopes. Microorganisms, keratinized cells, sebum, and hairs interact with each other to form the comedonal mass. Corynebacterium acnes and Pityrosporum ovale proliferate abundantly in close association with sebum and penetrate the keratinized cells. Fine structural details of bacteria and yeasts as well as features of host-microbial relationship have been elucidated.

Acne Vulgaris↗
PubMed1997

The changes of stratum corneum interstices and calcium distribution of follicular epithelium of experimentally induced comedones (EIC) by oleic acid.

Abnormal follicular keratinization is important for comedo formation in acne, but the precise mechanism is not known. A recent report about acne vulgaris suggested that an impaired water barrier function may be responsible for comedo formation, since the barrier dysfunction is accompanied by hyperkeratosis of the follicular epithelium. Furthermore, the integrity of the water barrier is crucial for the maintenance of the epidermal calcium gradient. Yet stratum corneum intercellular lipid structures, a major factor of the skin barrier function, and calcium distribution in the follicular epithelium of comedones, were not reported. To see SC intercellular lipid and calcium distribution of the follicular epithelium of comedo by electron microscopy, we applied oleic acid on the inner surface of the ear of New Zealand white rabbits to induce comedones, and then we obtained specimens and performed osmium and ruthenium tetroxide postfixation and calcium ion-capture cytochemical procedure. We found incomplete lipid bilayer structures, prominent dilatation of lacunar domains and the loss of follicular epidermal calcium gradient in experimentally induced comedones. From our results, we suggest that the permeability barrier disruption in oleic-acid-applied follicular epithelium can be induced by the changes of SC intercellular membrane structures and lacunar dilatation, and the calcium gradient is lost, so follicular epithelial proliferation and hyperkeratosis can be induced and then comedo formation occurs.

Acne Vulgaris↗
PubMed1997

Peculiar distribution of comedones: a report of three cases.

Three cases in which comedones developed in three different peculiar patterns are presented. Comedones developed along the stria nasi, the creases of the forehead and the ear lobule in a girl aged 14 and 2 men aged 73 and 72 years, respectively. A parallelism with keratosis punctata of the palmar creases is proposed. Some anatomical locations seem to facilitate the development of comedones in preexisting pilosebaceous units showing an apparently artificial pattern.

Acne Vulgaris↗
PubMedDate not supplied

Ultrastructure of human sebaceous follicles and comedones following treatment with vitamin A acid.

Ultrastructural findings in normal human sebaceous follicles, of comedones from acne patients, and from comedones during topical treatment with vitamin A acid (VAA) are described. In normal human sebaceous follicles, the two segments of the infundibulum-the acroinfundibulum and the infrainfundibulum-show differing ultramorphological patterns of keratinization. The incomplete horny layer of the infrainfundibulum is physiological and seems to be necessary for its normal function. On the other hand, no effective barrier function is established in this region. During comedo formation, excessive keratinization takes place in the infra-infundibulum, leading to a compact and coherent horny core. VAA-treatment leads to profound alterations of keratin production, with the appearance of small, irregular, non-coherent and foamy horny cells. The comedonal wall resumes almost physiological conditions. These changes are in agreement with experimental work using VAA in vivo and in vitro and may explain the therapeutic mechanism of action of this compound in the treatment of acne.

Acne Vulgaris↗
PubMedDate not supplied

Changes of comedonal cytokines and sebum secretion after UV irradiation in acne patients.

The aims of this study were to investigate the effect of UVA and UVB on comedones and sebum secretion in acne patients. Thirteen acne patients were irradiated by UVA (starting from 20J/cm2 and increasing 10% every day) and UVB (starting from 2/3 MED and increasing 10% every day). IL-1alpha, IL-6, IL-1 receptor antagonist (IL-1ra), IL-10 and GM-CSF were measured by ELISA. Measurement of sebum level was also performed. Sebum level was increased in the first three days by UVA (18.4 --> 37.6 microg/cm2) and UVB (19.1 --> 40.0 microg/cm2), but subsequently returned to normal values. Production of IL-1alpha, IL-1ra, IL-6, and IL-10 was generally higher on day 5 than on day 10. GM-CSF was not detected from all comedones. After UV irradiation, clinically stationary acne patients showed a higher increase in cytokine production compared with improved acne patients. It is suggested that IL-10 & IL-1ra have key roles in this cytokine network as the anti-inflammatory comedonal cytokines. They may play important roles in the immuno-regulation, which may be disturbed in stationary acne patients.

Acne Vulgaris↗
PubMed1985

Protein content of comedones from patients with acne vulgaris.

Characteristic early lesions in acne vulgaris are the open and closed comedones (blackheads and whiteheads) which are well known to contain a "plug" of cornified material. Histological analysis of these lesions has indicated that their protein content, presumed in part to be keratin, may be degraded, possibly by bacterial action, though this has never been adequately demonstrated biochemically. We have analysed the keratin content in a pool of material taken from a number of open comedones (approximately 200-500 mg by weight). Using a highly sensitive silver stain technique which can detect minute quantities of protein we have also been able to analyse individual lesions. In normal keratin extracted from human stratum corneum using a Tris-urea-mercaptoethanol buffer, SDS/polyacrylamide gel electrophoresis reveals the presence of a group of polypeptides with molecular weights in the range 66 000-44 000. Comedonal material contained bands of the same molecular weight but in addition to these undegraded keratin polypeptides, showed bands corresponding to molecular weights in the region of 15 000-10 000 and 30 000-25 000 indicating that the keratins in this material are partially degraded. Similar groups of low molecular weight polypeptides were observed when keratin was digested with purified V8 protease from Staphylococcus aureus. It is possible that inflammation around the follicle could involve the leakage of keratin digestion products into the dermis.

Acne Vulgaris↗
PubMed1988

The microbial content and complement C3 cleaving capacity of comedones in acne vulgaris.

Complement C3 deposition around lesions is an early event in the inflammation of acne vulgaris. The aims of this study were to determine the relationship between the capacity of individual comedones to cleave complement C3 and their microbial flora. The contents of 48 open comedones were expressed from the upper back of acne vulgaris patients and each comedo was homogenized individually and assayed for microbial content and capacity to induce cleavage of complement C3 in an in vitro assay system. An association between Propionibacterium population size and extent of C3 cleavage was found, but Staphylococcus and Pityrosporum population sizes did not appear to have an appreciable influence. A strong association between the weight of expressed material and C3 cleavage was apparent, irrespective of microbial population size. This observation suggests that comedones contain non-microbial material having the capacity to induce complement cleavage and hence initiate inflammation.

Acne Vulgaris↗
PubMed1979

Antibiotic sensitivity of comedonal Propionibacterium acnes.

Previous studies on antibiotic MIC levels for P. acnes and P. granulosum have shown them generally sensitive to therapeutic levels in both blood and surface lipids. The clinical response of acne vulgaris to antibiotic therapy is slower than one would anticipate from in vitro studies. It is also delayed well beyond the time tetracycline is known to appear in surface lipids. The concentration of antibiotics in comedonal material could be important, but it is not known. To determine the sensitivity level required for such an assay, MIC studies on P. acnes and P. granulosum from comedonal material were carried out from 0.05 to 25 microgram/ml. The assay would need to detect 0.05 microgram/ml or less in comedonal material. Interestingly, two organisms were found to be resistant to one or more antibiotics at the 25 microgram/ml level and another had a MIC level of 12.5 microgram/ml for tetracycline.

Ampicillin↗
PubMed1977

[Autoradiographic investigations in actinic (senile) comedones (author's transl].

Skin specimens of patients suffering from actinic comedones, young patients with acne vulgaris, and normal controls of the same age groups respectively were subjected to in vitro autoradiography. From the results it can be concluded, that a rise in the proliferational activity in the follicular infundibulum due to actinic stimuli is responsible for the development and growth of actinic comedones.

Acne Keloid↗
PubMed1980

Actinic comedonal plaque.

Solitary plaques developed on the sun-exposed and damaged skin of five elderly, fair-skinned individuals. The lesions, erythematous to bluish confluent nodules and plaques with a cribriform appearance and comedone-like structures, presented a distinctive histologic picture of dilated, keratin-filled follicles within a matrix of amorphous, damaged collagen. We believe these cases demonstrate a distinct entity within the realm of actinic dermatoses, for which the name "actinic comedonal plaque" seems appropriate.

Aged↗