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At least 19 recordsLinked to original sources
PubMed1977

[Coexistence of lichen planus and bullous pemphigoid (an immunofluorescence study of a "lichen pemphigoides") (author's transl)].

A 35 year old black man presented with a generalized eruption of lichen planus; subsequently tense blisters appeared within the lichenoid lesions and on clinically normal skin. Histopathological characteristics of lichen planus were present in the papules, and those of bullous pemphigoid were seen in the bullae taken from non-lichenoid skin. Direct immunofluorescence studies revealed immunological characteristics of lichen planus in skin and mucosal lesions of L. P. Bound IgG and beta1 C/beta1 A with tubular patterns were detected at the dermo-epidermal junction in all the skin fragments (clinically normal skin, bullous lesions lichenoid skin and mucous lesions). Indirect immunofluorescence studies showed at several intervals that the patient had circulating antibasement membrane zone antibodies (IgG; titres 1/50). This is the third published case in which immunofluorescence studies have established the "pemphigoid" nature of some bullous lichen planus. These findings are in favour of an immune disorder in lichen planus.

Adult↗
PubMed1975

Enzyme changes in lichen planus.

Untreated cases of lichen planus have been studied by histochemical techniques. The acid phosphatase reaction in the transitional zone has been quantitatively estimated and compared with the adjacent relatively normal epidermis. It was found that despite a thickened and accentuated granular layer as seen by routine histological methods there was a marked reduction in the intensity of the acid phosphatase reaction. The glucose-6-phosphate dehydrogenase reaction was marked in the upper layers of the epidermis in active lesions of lichen planus. This is similar to psoriasis, but different from normal human epidermis. The suggestion by other authors that lichen planus is an inborn error of metabolism is discussed. The dendritic cells of the epidermis as studied by the ATPase reaction are virtually absent in regions of active lichen planus and the possible significance of this is mentioned. The horny layer gives a dense reaction for phospholipids in lichen planus and this is similar to psoriatic keratin. The significance of this finding is considered.

Acid Phosphatase↗
PubMed2025

Fungal and algal lichen symbionts show different transcriptional expression patterns in two climate zones.

In the lichen symbiosis, the fungal and algal partners constitute a closely integrated system. The combination of fungal and algal partners changes along climate gradients in many species, and is expected to be adaptive. However, the functional mechanisms behind this symbiosis-mediated environmental adaptation are unknown. We investigated which transcriptional profiles are associated with specific fungal-algal symbiont pairings found in lichens from high-elevation (Lower Supratemperate) and low-elevation (Lower Mesomediterranean) sites at two extremes of a climatic gradient on Mount Limbara, Sardinia. Using laboratory-acclimatized thalli, we found that lichen fungal and algal symbionts show variable expression profiles between high- and low-elevation individuals: circadian- and temperature-associated genes for fungi and light-responsive genes for algae show climate-specific patterns. High- and low-elevation individuals differentially express sugar transporters in both symbionts, pointing to symmetrical and climate-dependent sugar transport mechanisms between them. A light pulse treatment identified asymmetries between fungal and algal light responses, with high- and low-elevation fungal symbionts but only low-elevation algal symbionts showing a response. Together, these results tie previously observed genomic variation along climatic gradients in a lichen species to functional differences in transcription for the fungal and algal symbionts, contributing to our understanding of environmental specialization and niche-specific partner combinations in lichens.

Lichens↗
PubMed1975

The lichen planus-like eruption after bone marrow transplantation.

A lichen planus-like eruption was seen in four patients after bone marrow transplantation. The skin and mucous membrane appearance closely mimicked lichen planus. The histopathology was also very similar to lichen planus. The occurrence of a lichen planus-like eruption (LPLE) after an immune basal cell damage related to the graft-versus-host reaction raised the question of the immune nature of this eruption. The correlation found between biological signs of graft-versus-host reaction and the out-break or relapse of the lichen planus-like eruption supports the hypothesis that the skin changes could be a sign of a chronic immune response against recipient epidermis.

Adolescent↗
PubMed1977

Contact allergy due to lichens in patients with a history of photosensitivity.

Ten patients with a history of photosensitivity and of a rash showed abnormal reactions to long-wave UVR. The rash occurred particularly in areas exposed to light, though other areas were occasionally involved. The development of the rash could in all patients be related to contact with lichens and although exposure to sunlight usually led to an aggravation of symptoms, some patients, particularly forestry workers, showed exacerbations even during the winter. Positive responses were observed in both irradiated and non-irradiated patch tests with different species of lichen and in several patients irradiation precipitated a stronger response. These findings suggest that lichens can cause both contact and photocontact dermatitis. The suspected allergens contained in these lichens are atranorin, physodalic and pysodic acids.

Adult↗
PubMed1979

HLA antigens in patients with lichen planus.

HLA-ABC antigens were determined in 89 patients with biopsy-confirmed lichen planus, and the HLA antigen frequencies were compared with those in 1967 controls. The younger patients were predominantly male, the older patients predominantly female. No significant association was found between HLA types and lichen planus in this study. A slightly greater incidence of HLA-A3 and B5 antigens was seen, but this increased frequency was not as pronounced as reported by others. When combined, available data on HLA and lichen planus indicate a slightly, but significantly, increased frequency of HLA-A3. None of the HLA antigens known to be associated with insulin-dependent diabetes are associated with lichen planus.

Adolescent↗
PubMed1978

An assessment of vulval lichen sclerosus.

Vulval lichen sclerosus (L.S.) has been assessed clinically, colposcopically, and histologically to ascertain the suitability of including this condition in the nomenclature proposed by the International Society for the Study of Vulval Disease (I.S.S.V.D). In many cases the macroscopic appearance of lichen sclerosus is characteristic, but this is not always the case. Histologically, the appearances of the dermal hyaline change, the reduction in the length and the number of rete pegs, to a lesser extent thinning of the dermis and sometimes thinning of the epidermis are characteristics. The presence of dermal inflammatory cells and changes in the thickness of the keratin layer are, however, much more variable. Exact measurements of the various layers of the vulval skin are not necessary in the routine assessment of lichen sclerosus. The present study justifies the inclusion of lichen sclerosus on histological criteria in the I.S.S.V.D.'s nomenclature.

Female↗
PubMed1976

Lichens as indicators of air pollution.

Field and laboratory studies have demonstrated that lichens are extremely sensitive to sulfur dioxide and that lichens are fairly sensitive to hydrogen fluoride and heavy metals. Further studies are necessary to assess lichens' relative sensitivity to oxidant air pollutants.

Air Pollutants↗
PubMed1977

Smoking habits of 611 patients with oral lichen planus.

The smoking habits of 611 patients (68 per cent females and 32 per cent males) with oral lichen planus were studied. Forty-six per cent were daily smokers, 4 per cent smoked only at social events, and 50 per cent were nonsmokers. In comparison with the nonsmokers, the daily smokers showed significantly lower prevalences of reticular and atrophic types of oral lichen planus lesions and a significantly higher prevelance of the plaque type (P less than 0.001). It is suggested that these findings depend on a mechanism whereby original atrophic and reticular types of lesions are altered into the plaque type of lesions under the influence of smoking. The question arises whether such plaque type of lesion can be regarded as leukoplakias which have been superimposed on the oral mucosa affected by lichen planus.

Adolescent↗
PubMed1978

Mixed lichen planus-lupus erythematosus disease.

Two patients are reported with clinical symptoms of systemic lupus erythematosus associated with centrally ulcerated hypertrophic plaques and lip lesions. Histological findings from various sites were features of both lupus erythematosus and lichen planus. An increase in acid mucopolysaccharides and a thickened basement membrane which were present in some biopsies were interpreted as lupus erythematosus. The deposition of immunoglobulins and fibrinogen seemed to favor lupus erythematosus but these findings may also be seen in lichen planus. Four possible interpretations of the findings are discussed. The term "mixed lichen planus--lupus erythematosus disease" may be appropriate for these patients.

Basement Membrane↗
PubMed1977

Arterial blood pressure in patients with oral lichen planus.

The arterial blood pressure of 121 patients with oral lichen planus was determined using the auscultatory method. These values were then compared with those previously found in a general adult population. No significant difference was found betwween the values of the lichen planus patients and those of the general population. The present investigation does not support the hypothesis of a relationship between lichen planus and hypertension.

Adult↗
PubMed1977

Glucose tolerance in patients with oral lichen planus.

Of 123 patients with oral lichen planus two were known diabetics. The remainder were tested for fasting glucosuria, 113 for fasting blood glucose and 103 also with an oral glucose tolerance test. According to the criteria of WHO, 18 of the 123 patients were diabetics. In most of these patients the oral glucose tolerance test was only slightly abnormal. No decrease of the glucose tolerance with increasing duration of lichen planus was demonstrable. Comparison with two general population studies did not reveal any significant difference between the glucose tolerance of the lichen planus patients and that of the general population samples.

Adult↗
PubMed1977

Immunohistochemical study of lichen planus.

The distribution of IgM and IgG in 20 cases of lichen planus and five cases of non-specific inflammation were studied by the unlabelled antibody-enzyme (PAP) technique. Routine paraffin sections were used. In lichen planus deposits of immunoglobulins were seen in and around epithelial cells, in colloid bodies, at epidermo-dermal junctions, and in some inflammatory cells. All cases examined for IgM and eight out of 13 cases examined for IgG were positive. The peripheral migrating epidermal cells were mostly negative. The application of the PAP technique to skin biopsy and the significance of the findings in lichen planus are discussed.

Adult↗
PubMed1979

Erythroplakic lesions in relation to oral lichen planus.

In a cohort of 740 referred patients with oral lichen planus eight patients were found with a sharply demarcated slightly depressed erythroplakic area. The histological examination of the biopsies from the erythroplakic lesion of the 8 patients showed seven with epithelial dysplasia. In addition, two of the lesions revealed a squamous cell carcinoma. In the erythroplakic lesion without dysplasia the histological picture was found to be characteristic of lichen planus. All eight patients were seen at later follow-up examinations (median observation period: 3.6 years) and in one patient a squamous cell carcinoma arose in the erythroplakic lesion during the control period. It is concluded that the reported erythroplakic lesions in relation to oral lichen planus seem to be premalignant and they should be followed and/or treated like oral erythroplakias.

Aged↗
PubMed1979

Lichen planus and bullous pemphigoid.

A patient is described who had clinical and histopathological features of lichen planus and bullous pemphigoid; deposits of in vivo bound C3 at the basement membrane zone, which, at the electron microscopy level, were deposited in the lamina lucida; and with circulating IgG antibasement membrane zone antibodies which exhibited a pronounced C3 binding capacity. The similarity of our case to others described in the literature suggests that bullous lichen planus in fact represents the coexistence of two distinct diseases, namely lichen planus and bullous pemphigoid.

Adolescent↗
PubMed1979

Photodynamic reactions induced by compounds derived from lichens.

Contact dermatitis from lichens is now well documented but the possible influence of exposure to sunlight is less clear. Positive reactions on photopatch testing has recently been described, but whether this represented an unspecific exacerbation or a true photoallergic response was difficult to evaluate. In this study 13 different substances derived from lichens commonly found in nature were investigated with regard to their capacity to induce photo-oxidative membrane damage, as revealed by the photohemolysis technique. It was found that the earlier suggested ability to induce photosensitization could be confirmed for several of the lichen compounds investigated. It was also shown that singlet state excited oxygen may participate to some degree in some of these reactions.

Adult↗
PubMed1977

[The neural periphery in lichen planus lesions (author's transl)].

In 12 patients suffering from generalized Lichen planus (L.p.) the neural periphery of lesions was studied by modern histochemical and electron microscopical methods. In contrast to the investigations published until now on this subject no signs of neural hyperplasia in L.p. could be found. Only some nerves localized in the Lichen planus infiltrate exhibited morphological changes indicating increased neural de- and regeneration in this region. According to the results obtained the nerve changes in L.p. are caused by the typical inflammatory reaction found in this dermatosis. Therefore the neural theory of L.p. cannot be sustained on a histological basis.

Adolescent↗
PubMed1978

Lichen planus: immunologic and morphologic identification of the submucosal infiltrate.

The purpose of this investigation was to specifically identify T cells, B cells, and histiocytes in the infiltrate typically seen in lichen planus. In frozen tissue sections, AET-treated sheep erythrocytes formed immunologic rosettes with the lymphocytes in the infiltrate, designating them as T cells. Rosette assays with reagent erythrocytes, IgGEA, IgMEA, IgMEAC, and E resulted in nonadherence, indicating a lack of B cells and macrophages, and indirectly implicating them as T cells. Scanning electron microscopy of the cellular infiltrate, in situ, showed that the cells had smooth, nonvillous surfaces. These observations were consistent with a T cell origin and were considered supportive of the immunologic data. The results of this investigation support the hypothesis that lichen planus is a disease mediated by thymus-dependent lymphocytes.

Connective Tissue↗