Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “COMEDONES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 361 records · Page 20Linked to original sources
PubMed1989

Stratum corneum activation of complement through the antibody-independent alternative pathway.

We provide evidence that stratum corneum (SC) activates complement through the alternative pathway to generate C5a anaphylatoxin. By immunofluorescence studies it was shown that in addition to circulating IgG autoantibody, there were anti-SC antibodies of IgM and IgA classes in the sera from normal individuals. However, all the titers were significantly lower than the level of C3 deposition between corneocytes. By contrast, no C1q deposition occurred. Immunoelectrophoretically the orthokeratotic SC homogenates were found to induce the conversion of C3 from native C3 to C3b in fresh human serum even when the classic pathway was blocked by Ca2+-chelation. Enzyme immunoassay showed that factor B split product, Bb, was generated by the SC homogenates in the Ca2+-chelated serum. Radioimmunoassay for C5a also demonstrated that the SC homogenates could generate C5a anaphylatoxin in serum to an extent similar to that in non-treated serum when restricted to the alternative pathway activation; neutrophil chemotactic activity was generated in Ca2+-chelated serum at levels comparable to that generated in non-treated fresh serum. We separated the SC samples into a cornified envelope and soluble and keratin fractions. The cornified envelope was more effective in activating complement. This activity resided in heat-stable and non-lipid substances of corneocytes. Our hypothesis is that when the SC comes in contact with serum, it activates complement mainly through the alternative pathway to induce chemotactic C5a anaphylatoxin. Hence, inflammation in normal individuals after a traumatic injury to the skin or rupture of acne comedones, or epidermal cysts and possibly the formation of subcorneal sterile pustules noted in several dermatoses are explainable through this mechanism.

Adult↗
PubMed1999

Aggregated dilated pores.

We report a 74-year-old Japanese man who had a 10-year history of approximately 20 open comedones crowded onto his lateral neck. An excisional biopsy revealed that each comedo was histologically a dilated pore. Dilated pores are usually solitary. The multiple and aggregated dilated pores seen in our case have never been reported.

Aged↗
PubMed2005

Benzoyl peroxide, adapalene, and their combination in the treatment of acne vulgaris.

Benzoyl peroxide and adapalene are among the most effective topical agents used in the treatment of acne. We planned an open-labeled, prospective study to compare the effects and side effects of these two drugs alone and in combination in the treatment of acne vulgaris. One hundred and five consecutive patients (30 men and 75 women) with acne vulgaris were included in this study. The patients were randomly divided into three groups with 35 patients in each. The groups were randomly assigned to 0.1% adapalene gel, 5% benzoyl peroxide lotion, or combination of 0.1% adapalene gel +5% benzoyl peroxide treatment. Acne lesions were classified as noninflammatory (open and closed comedones) and inflammatory (papule, pustule, nodule, cyst), and the lesions on the face were counted before the therapy, during the control visits, and after the treatment. Erythema, dryness, burning, and other side effects were recorded during the treatment. The mean age of the patients was 18.44 +/- 3.75 years. Eight patients were excluded because of noncompliance with the treatment regimen or the follow-up schedule, and four patients were excluded due to allergic contact dermatitis. The study revealed that all three therapy protocols were effective in treating noninflammatory and inflammatory lesions in acne vulgaris (p<0.05) and that there was no significant difference between the groups in efficacy or side effects (p>0.05). Adapalene and benzoyl peroxide are effective and well tolerated agents for acne vulgaris; combination therapy has no superiority over adapalene or benzoyl peroxide alone.

Acne Vulgaris↗
PubMed1977

Cohesion of horny cells during comedo formation. An electron microscope study.

Cohesion between horny cells was studied in experimentally induced comedones, from the rabbit's external ear canal. It occurred in two different ways: initially, by the persistence of desmosones and desmonosmal bodies (fusiform electron dense bodies), which loosely held the horny cells together; later, and to a lesser extent, by tight junctions, which tightly bound the horny cells together. A gradual decrease in the numbers of membrane coating granules was observed.

Acne Vulgaris↗
PubMed1978

Enhancement of comedogenic substances by ultraviolet radiation.

Ultraviolet radiation enhanced the capacity of human sebum, sulphur, cocoa butter, squalene, and coal tar to produce comedones in the external ear canals of rabbits. An enhancement of the comedogenicity of coal tar and squalene was similarly demonstrated in man. We conjecture that in occasional patients sunbathing may aggravate acne by augmenting the comedogenicity of sebum.

Acne Vulgaris↗
PubMed1978

A quantitative study of membrane coating granules in follicles undergoing experimental comedo formation.

Membrane coating granules (MCGs) may be required for normal keratinization. Comedone formation is associated with abnormal keratinization, and so the MCGs in sebacaous follicles were counted during experimental comedogenesis in the rabbit. During induced comedo formation with 50% oleic acid in paraffin oil, the numbers of MCGs decreased significantly; first, at the epidermis and mouth of the follicle and then later, at the follicular canal and common sebaceous duct. The maximum decrease of about 40% was reached by the 6th day in these regions. Throughout the treatment, the MCG count in the individual sebaceous ducts remained fairly constant.

Acne Vulgaris↗
PubMed1989

A 4% erythromycin and zinc combination (Zineryt) versus 2% erythromycin (Eryderm) in acne vulgaris: a randomized, double-blind comparative study.

A double-blind, randomized multi-centre study was performed to evaluate the efficacy of a 4% erythromycin and zinc combination (Zineryt) versus 2% erythromycin (Eryderm). One-hundred and twenty-two patients suffering from acne vulgaris were treated with either Zineryt lotion or 2% erythromycin lotion. Acne grading and lesion counts for comedones, papules, pustules, nodules and macules were performed at each visit at 0, 1, 2, 4, 8 and 12 weeks. Treatment with Zineryt lotion was found to be more effective than with 2% erythromycin as regards the reduction in number of the acne lesions and the severity grade of the acne.

Acetates↗
PubMed1990

Naevus corniculatus: a new acantholytic disorder.

We describe a 33-year-old man with an unusual epidermal naevus that followed the lines of Blaschko. There were filiform hyperkeratoses, large cutaneous horns and lesions that resembled giant comedones and linear hyperkeratotic plaques. All of these lesions showed acantholysis without dyskeratosis. As the disorder is characterized by multiple small or large horn-like processes, we propose the term 'naevus corniculatus'.

Acantholysis↗
PubMed1991

Efficacy and safety of CD 271 alcoholic gels in the topical treatment of acne vulgaris.

CD 271, a naphthoic acid, is a powerful modulator of epidermal differentiation. This double-blind, randomized study compared the efficacy and safety of two concentrations (0.03% w/w and 0.1% w/w) of CD 271 alcoholic gel, with 0.025% w/w tretinoin gel in 72 male patients with acne vulgaris over a period of 12 weeks. Efficacy was measured by counting facial inflammatory and non-inflammatory lesions and by grading the severity of the acne at each visit. Skin tolerance was assessed with subjective symptoms, such as burning and pruritus, as well as clinical assessment of erythema, dryness and scaling on the treated areas. The alcoholic 0.1% CD 271 gel was as effective as 0.025% tretinoin gel in reducing total comedone counts (83% reduction for both products after 12 weeks' treatment). The reduction in the number of inflammatory lesions and the total number of acne lesions were significantly greater with 0.1% CD 271 gel than with tretinoin gel (69% and 79% for 0.1% CD 271, 50% and 73% for tretinoin gel, respectively, P less than 0.05). All three treatments were well tolerated and there were no changes in any major blood parameters. No CD 271 could be detected in blood plasma at the end of the study (detection limit = 1 ng/ml).

Acne Vulgaris↗
PubMed2005

Does facial sebum excretion really affect the development of acne?

BACKGROUND: It is generally accepted that the severity of acne is correlated with facial sebum secretion. However, previous studies on the relation between seborrhoea and the development of acne did not consider topographical differences in facial sebum secretion and used relatively vague acne severity grading systems. OBJECTIVES: To elucidate the relation between topographical variations in facial sebum secretion and the severity of acne in women. METHODS: Forty-six female controls and 46 women with acne were included in this study. The Sebumeter was used to measure facial sebum secretion in the following facial areas: forehead, nose, chin, and right and left cheek. We counted noninflammatory comedones and inflammatory acne lesions in the same areas. We compared sebum secretion between patients with acne and controls, and analysed the relation between the quantity of sebum secreted and the number of acne lesions. RESULTS: Sebum secretions in the whole face and in the T- and U-zones (areas of high and low sebum secretion, respectively) were higher in patients with acne than in controls. There was no correlation between sebum quantity and acne lesion count in most facial regions. CONCLUSIONS: Increased levels of facial sebum secretion were observed in patients with acne. Our findings indicate that increased sebum levels do not directly cause development of acne lesions.

Acne Vulgaris↗
PubMed1993

Chloracne--study of an outbreak with new clinical observations.

A recent outbreak of chloracne in 17 workers is reported at a plant manufacturing dichloroaniline derivatives. Comedones developed 6-12 weeks after accidental exposure to the chloracnegenic contaminants and were present in every case. Cutaneous xerosis and a folliculitis, previously only rarely described as manifestations of chloracne, were noted in half the patients. The pathogenesis of these lesions is uncertain but may involve a disorder of keratinization.

Acne Vulgaris↗
PubMed2006

An evaluation of the clinical, cytological, infectious and histopathological features of feline acne.

Clinical, cytological, microbial and histopathological features of feline acne were investigated in 22 cats referred or volunteered to a veterinary dermatology practice in the south-west region of the USA. For comparison, same parameters were evaluated in five unaffected pet cats. Additionally, all cats were evaluated by immunohistochemistry (IHC) for the presence of feline calicivirus (FCV) and feline herpes virus (FHV-1) in acne lesions. The age of onset of acne in affected cats ranged from 6 months to 14 years with a median of 4 years. The most common dermatologic lesions were comedones (73%), alopecia (68%), crusts (55%), papules (45%) and erythema (41%). Pruritus was reported in 35% of the affected cats. Cytological evidence of Malassezia pachydermatitis was present on 4/22 (18%) of affected cats. Microsporum canis was isolated from a single affected cat. Bacteria were isolated from 10 of the 22 (45%) affected cats; coagulase-positive staphylococci and alpha-haemolytic streptococci were most common. Histopathological features included lymphoplasmacytic periductal inflammation (86%), sebaceous gland duct dilatation (73%), follicular keratosis with plugging and dilatation (59%), epitrichial gland occlusion and dilatation (32%), folliculitis (27%), pyogranulomatous sebaceous adenitis (23%) and furunculosis (23%). In one affected cat from a household with five cats, simultaneously having feline acne, FCV antigen was detected in the biopsy of the chin by IHC. Chin tissue samples from all other affected cats, as well as the five healthy cats, were negative by IHC for FCV and FHV-1 antigens.

Acne Vulgaris↗
PubMed1978

Acne treated with a tropical tetracycline preparation: results of a one-year multi-group study.

One hundred five patients were treated effectively with topically applied tetracycline in an ethanol-water solution with n-decyl methyl sulfoxide, and observed for a year. Comedones and cystic lesions were least responsive to topical tetracycline. Side effects, which were minor, included yellow staining of facial skin and stinging after application. Two patients, one with juvenile diabetes and one with congenital nephritis, successfully used the preparation without adverse effects.

Acne Vulgaris↗
PubMed1978

Comparative effectiveness of benzoyl peroxide and tretinoin in acne vulgaris.

A controlled, randomized clinical study comparing different commercially available benzoly peroxide gels and tretinoin cream was undertaken by four investigators using similar protocols and case report forms. Results were based on lesion-count reduction over an 8-week period. No significant difference in reduction of total acne lesions was detected between the benzoyl peroxide gels and tretinoin cream. However, benzoyl peroxide was significantly better (P less than .02) in reduction of papules and as good as tretinoin in reduction of comedones. Results of this study suggest that excessive drying and peeling are not essential in the reduction of acne lesions.

Acne Vulgaris↗
PubMed1981

Localized comedo formation after cobalt irradiation.

Following Cobalt-60 irradiation for a left frontotemporal tumor, a 61-year-old woman developed comedones on the forehead. These changes responded to conventional acne therapy with retinoic acid. Multiple acneigenic factors were implicated in the pathogenesis of her lesions.

Brain Neoplasms↗
PubMed1996

Chloracne in the 1990s.

BACKGROUND: Chloracne is a disease associated with toxicity of halogenated compounds used in some industrial processes. A patient affected by chloracne led us to study a total of nine cases from a single factory. METHODS: We studied the clinical features of nine patients exposed chronically to chlorobenzenes. On all of them blood samples were drawn and biopsies of affected skin and liver were taken. Their work environment was visited and studied. RESULTS: All nine patients were men and had polymorphic skin lesions, characterized mainly by comedones and cysts. They had chronic conjunctivitis and seven had cysts in the Meibomian glands. All of them had polyneuropathy and liver damage and seven had hypertriglyceridemia. Compounds known to cause chloracne were found in exceedingly high concentrations in the water used in the workplace. CONCLUSIONS: Every patient exposed to halogenated compounds with the cutaneous manifestations of chloracne should be carefully investigated for systemic complications (such as ophthalmic, neuropathic, hepatic, and lipoprotein abnormalities).

Acne Vulgaris↗
PubMed2007

Treatment of acne vulgaris without antibiotics: tertiary amine-benzoyl peroxide combination vs. benzoyl peroxide alone (Proactiv Solution).

BACKGROUND: Concerns have arisen over the development of antibiotic-resistant organisms due to the prolonged use of oral and topical antibiotics in acne vulgaris. We have previously demonstrated that benzoyl peroxide used in consort with a chemical with an accessible tertiary amine, such as an allylamine, increases radical activity and biological effect. OBJECTIVES: The purpose of this pilot study was to assess the efficacy of two nonantibiotic topical remedies for mild to moderate acne, with one of the agents being a combination of benzoyl peroxide with butenifine, an allylamine. METHODS: In an open-label, patient-satisfaction, 8-week comparative study, 23 patients demonstrating mild to moderate facial acne were given randomly either benzoyl peroxide in Proactiv Solution or the combination of benzoyl peroxide with an allylamine. RESULTS: The allylamine-benzoyl peroxide combination therapy outperformed Proactiv Solution during each 2-week stage of evaluation in terms of reduction of comedones, inflammatory lesions, and degree of oiliness. There was a marked preference for the allylamine-benzoyl peroxide combination in terms of patient satisfaction. CONCLUSIONS: Benzoyl peroxide used in consort with antimicrobial agents that contain an accessible tertiary amine, such as erythromycin, has previously been shown to increase radical activity and biological effect. Trials of short duration with small numbers of patients do not adequately inform practitioners about whether the combination of allylamines with benzoyl peroxide is a viable alternative to topical antibiotic therapy for acne. Nevertheless, the higher satisfaction with the allylamine-benzoyl peroxide combination certainly warrants further investigation.

Acne Vulgaris↗
PubMed1997

Descriptive epidemiology of acne vulgaris in the community.

Acne is a common skin condition. No universally accepted standardized classification system for acne vulgaris exists, although there is a strong need for it. Thus, the clinical definition of acne has been unclear in many studies. The reported prevalence of acne varies from 35 to over 90% of adolescents at some stage. In some studies the prevalence of comedones approaches 100% in both sexes during adolescence. The prevalence of acne varies between sexes and age groups, appearing earlier in females than in males, possibly reflecting the earlier onset of puberty. There is a greater severity of acne in males than in females in the late teens, which is compatible with androgens being a potent stimulus to sebum secretion. The prevalence of acne at a given age has been shown to be highly dependent on the degree of sexual maturity. Acne commonly shows a premenstrual increase in women. Some studies have detected seasonal variability in acne vulgaris, with the colder months associated with exacerbation and the warmer months showing improvement. Other studies have not confirmed these findings. Several studies that have investigated the psychosocial impact of acne have had conflicting results. The prevalence of severe acne has decreased over the past 20 years due to improved treatment. The general prevalence figure for acne may be confounded by treatment and this factor needs to be accounted for when collecting data.

Acne Vulgaris↗