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PubMed2005

Occupational allergic contact dermatitis from lichens in present-day Finland.

Lichens are abundant in forests, living on trees, soil, stones and rocks. They contain usnic acid and other lichen acids that are contact allergens. Lichens and liverworts cause woodcutter's dermatitis, eczema that appears in the forest on the bare skin areas, especially in cold and wet weather. Occupational allergic contact dermatitis from lichens occurs in forestry and horticultural workers and in lichen pickers. Lichens can cause immediate allergy, contact urticaria, rhinitis and asthma and probably also photoallergic contact dermatitis. Lichens are used for the manufacture of oak moss absolute, a fragrance constituent. Oak moss absolute contains lichen acids and is one of the commonest contact allergens. Lichen acid allergy develops either from contact with lichens or from fragrances. We describe 4 cases of occupational allergic contact dermatitis from lichens during the past decade: 2 were farmers and 2 gardeners. 3 of them had allergic reactions to fragrance mix and oak moss absolute. Lichen contact allergy is an old, partly forgotten, syndrome that should be remembered for symptoms in contact with barked wood or wood dust.

Agricultural Workers' Diseases↗
PubMed2006

Cytokine alterations in lichen sclerosus: an immunohistochemical study.

BACKGROUND: Although the histology of lichen sclerosus is characteristic, the precise nature of the inflammatory changes and the signals provoking them is uncertain. OBJECTIVES: To delineate the inflammatory changes in lichen sclerosus more accurately by studying cytokine changes. METHODS: An immunohistochemical study of 12 specimens of genital lichen sclerosus and one specimen of extragenital lichen sclerosus was undertaken using monoclonal antibodies to interferon (IFN)-gamma, IFN-gamma receptor, tumour necrosis factor (TNF)-alpha, interleukin (IL)-1alpha, IL-2 receptor (CD25), intercellular adhesion molecule-1 (ICAM-1) and its ligand CD11a. Control specimens were seven specimens of normal vulva obtained during gynaecological procedures, three specimens of normal skin, adjacent uninvolved thigh from three of the patients with lichen sclerosus, five specimens of nonvulval psoriasis, four specimens of nonvulval lichen planus and two specimens from chronic wounds. RESULTS: The lichen sclerosus specimens demonstrated slightly increased staining for IFN-gamma within the epidermis compared with the normal vulva and nonvulval skin. There was increased dermal staining for IFN-gamma both within the pale zone of the upper dermis and within the inflammatory zone below this. We confirmed our previous demonstration that in lichen sclerosus HLA-DR immunostaining is increased in association with vascular endothelium, the inflammatory cell infiltrate and around the keratinocytes. The areas of the epidermis with the strongest immunostaining for HLA-DR generally also had the strongest staining for IFN-gamma. In the lichen sclerosus specimens the zone of inflammation also demonstrated increased immunostaining for TNF-alpha, IL-1alpha, IFN-gamma receptor, CD25, CD11a and ICAM-1 while the zone of sclerosus demonstrated a smaller increase in immunostaining for IFN-gamma receptor, TNF-alpha, CD11a and ICAM-1, and the epidermis demonstrated increased staining for ICAM-1. CONCLUSIONS: The increased staining for IFN-gamma, TNF-alpha, IL-1alpha, IFN-gamma receptor, CD25, CD11a and ICAM-1 suggest that the cytokine response in lichen sclerosus shares characteristics of the cytokine response in lichen planus and chronic wounds.

Aged↗
PubMed1998

Psychologic factors and oral lichen planus. A psychometric evaluation of 100 cases.

OBJECTIVE: The purpose of this study was to analyze the importance of psychologic factors in patients with oral lichen planus, and attempts were made to identify possible personality features characteristic of patients with oral lichen planus. STUDY DESIGN: The study involved 100 patients with oral lichen planus (group 1) and 50 control subjects (group 2). We applied the following psychometric tests to both groups: Spielberger State-Trait Anxiety Inventory, Cattell Personality Questionnaire 16PF, Hassanyeh Rating of Anxiety-Depression-Vulnerability, Beck Depression Inventory, Raskin Depression Screen, and Covi Anxiety Screen. RESULTS: The patients with oral lichen planus were found to exhibit greater anxiety, as reflected by statistically significant scores with the anxiety tests that were used (Spielberger State-Trait Anxiety Inventory, Cattell Personality Questionnaire 16PF, Hassanyeh Rating of Anxiety-Depression-Vulnerability, and Covi Anxiety Screen). The patients with oral lichen planus likewise exhibited greater depression than the controls in all 3 depression tests applied (Beck Depression Inventory, Hassanyeh Rating of Anxiety-Depression-Vulnerability, and Raskin Depression Screen) and were more vulnerable to psychic disorders on the basis of the PD subscales (vulnerability) of the Hassanyeh questionnaire. Three features (conformity to the group, astuteness, and rebelliousness) defined the personalities of our patients with oral lichen planus, according to the Cattell 16PF questionnaire. Finally, those patients with erosive lichen planus exhibited higher depression scores than patients with nonerosive lichen planus. CONCLUSIONS: Despite the higher anxiety scores observed in patients with oral lichen planus, it was not established that the observed psychologic alterations constitute a direct etiologic factor of oral lichen planus; nor was it established that such alterations are a consequence of oral lichen planus and its lesions.

Analysis of Variance↗
PubMed1999

The evaluation of cutaneous, genital, scalp, nail, esophageal, and ocular involvement in patients with oral lichen planus.

OBJECTIVE: Lichen planus, in its classical presentation, involves the oral cavity and skin. This study evaluated patients with oral lichen planus for extraoral manifestations of the disease. STUDY DESIGN: A total of 584 patients with oral lichen planus were evaluated for cutaneous, genital, scalp, nail, esophageal, and ocular lichen planus. RESULTS: Extraoral manifestations included cutaneous lichen planus in 93 patients, genital lichen planus in 19% of 399 examined women and 4.6% of 174 examined men, nail involvement in 11 patients, lichen planopilaris in 6 patients, esophageal lichen planus in 6 patients, and conjunctival lichen planus in 1 patient. Thirty-three patients developed lichen planus in 3 or more sites. CONCLUSIONS: Because a relatively high percentage of patients with oral lichen planus develop extraoral manifestations, a thorough evaluation should routinely be performed. A complete history and physical examination by a multidisciplinary group of health care providers uncovers common and uncommon extraoral features of the disease.

Adult↗
PubMed2002

Oral lichen planus pathogenesis: A role for the HCV-specific cellular immune response.

Hepatitis C virus infection can be associated with different extrahepatic manifestations, including lichen planus; however, no clear role for HCV in their pathogenesis has been established. T cells were isolated from lichen biopsy specimens of 7 HCV positive patients with oral lichen planus. HCV-specific CD4(+) T-cell lines were obtained in 4 patients from lichen lesions but only in 2 of them from the peripheral blood. Different clonal populations were found in oral tissue and peripheral blood of individual patients, as shown by TCR-Vbeta analysis of antigen-specific T cells. Frequency of HCV-specific CD8(+) cells tested with 4 different HCV tetramers was significantly higher in the lichen tissue than in the circulation; moreover, lichen-derived HCV-specific CD8(+) T cells showed the phenotype of recently activated T cells because most of them were CD69(+) and produced interferon gamma (IFN-gamma) but expanded poorly in vitro upon antigen stimulation. The specificity of HCV-reactive T-cell recruitment into the lichen tissue was further confirmed by the absence of HBV-specific T cells within lichen lesions in 3 additional patients with lichen planus associated with HBV infection. Our study shows HCV-specific T-cell responses at the site of the lesions of an HCV-associated dermatologic disease, sustained by HCV-specific T cells with phenotypic and functional characteristics of terminally differentiated effector cells. In conclusion, this finding and the detection of HCV RNA strands in the lichen tissue strongly suggest a role for HCV-specific T-cell responses in the pathogenesis of oral lichen planus associated with HCV infection.

Antibody Specificity↗
PubMedDate not supplied

[Lichen pemphigoid associated with developing hepatitis B in a child].

INTRODUCTION: Lichen planus pemphigoides is a rare acquired auto-immune bullous dermatosis which usually affects adults. Only four cases have been reported in children. We describe a new case of lichen planus pemphigoides in a child unusual by its association with an evolutive hepatitis B and by the occurrence of a lichen planus relapse. CASE REPORT: A 10-year-old African boy has been seen for a pruritic dermatosis with papular lichenoid lesions on the trunk and the limbs and blisters on the lower limbs, both arise on lichen planus lesions and normal skin. The diagnosis of lichen planus pemphigoides was confirmed by histology which showed the features of lichen planus on a papule and of a sub-epidermal split on a bulla and by direct and indirect immunofluorescent studies which revealed an IgG and C3 linear deposit at the dermo-epidermal junction and the presence of circulating IgG anti-basement membrane zone antibodies. Laboratory investigations showed an evolutive hepatitis B (HBsAg +). Healing was obtained by dapsone and topical steroid therapy. Eight months after withdrawal of treatment the patient presented a non-bullous relapse of lichen planus. The histology showed a typical aspect of lichen planus and the immunofluorescence studies were negative. The hepatitis B serology was unchanged. The lesions rapidly improved with topical steroid and coaltar. One year later the patient exhibited few slight lichen planus lesions on the limbs and the hepatitis B serology showed the onset of sero-conversion. DISCUSSION: Lichen planus and lichen planus pemphigoides are probably variants of the same disease. Their successive occurrence in our case report favours this hypothesis as does the association with an hepatitis B.

Administration, Cutaneous↗
PubMed2004

Pimecrolimus for the treatment of vulvar lichen sclerosus in a premenarchal girl.

BACKGROUND: Lichen sclerosus is a chronic cutaneous disorder with a predilection for the vulva. Lichen sclerosus affects more than one in 900 girls. Superpotent corticosteroids like clobetasol propionate are the most effective treatment for vulvar lichen sclerosus. However, recurrence after stopping steroids is very high. As repeated courses of corticosteroids are frequently needed, there are concerns about potential side effects. Therefore, a treatment regimen that does not rely on corticosteroids may be beneficial. As lichen sclerosus is a T-lymphocyte mediated disorder, it has been suggested that pimecrolimus, a topical T-lymphocyte inhibitor, may be safe and effective for the treatment of lichen sclerosus in children. CASE REPORT: A 10-year-old girl with lichen sclerosus was initially treated with clobetasol. Remission was achieved, but 3 months later she had a recurrence. Subsequent treatment with clobetasol led to a breakdown of her peri-anal skin with a superimposed infection. She was then treated with pimecrolimus and remission was achieved. She has had no recurrence of active lichen sclerosus and has less burning with pimecrolimus than with clobetasol. CONCLUSION: Pimecrolimus may be an effective treatment of vulvar lichen sclerosus. Pimecrolimus has been shown to be very safe in the pediatric population for the treatment of mild to moderate eczema, without causing dermal atrophy, tachyphylaxis, striae, rebound flares, or hypothalamic-pituitary axis suppression. As the recurrence rate of active lichen sclerosus in prepubertal girls treated with topical corticosteroids is high, and the majority of prepubertal girls with lichen sclerosus continue to have disease after menarche, a treatment regimen that does not rely on corticosteroids may be beneficial.

Administration, Cutaneous↗
PubMed1999

Autoantibodies in lichen planus pemphigoides react with a novel epitope within the C-terminal NC16A domain of BP180.

Lichen planus pemphigoides is an autoimmune subepidermal blistering disease. The finding of immunoglobulin G antibodies directed against the basement membrane zone differentiates it from bullous lichen planus. The aim of this study was to identify the target antigen of lichen planus pemphigoides autoantibodies. Sera from lichen planus pemphigoides patients (n = 4) stained the epidermal side of NaCl-split human skin in a pattern indistinguishable from that produced by bullous pemphigoid sera. In bullous pemphigoid, the autoimmune response is directed against BP180, a hemidesmosomal transmembrane collagenous glycoprotein. We previously demonstrated that bullous pemphigoid sera predominantly react with a set of four epitopes (MCW-0 through MCW-3) clustered within a 45 amino acid stretch of the major noncollagenous extracellular domain (NC16A) of BP180. By immunoblotting and enzyme-linked immunosorbent assay, lichen planus pemphigoides sera were also strongly reactive with recombinant bullous pemphigoid 180 NC16A. The lichen planus pemphigoides epitopes were further mapped using a series of overlapping recombinant segments of the NC16A domain. All lichen planus pemphigoides sera reacted with amino acids 46-59 of domain NC16A, a protein segment that was previously shown to be unreactive with bullous pemphigoid sera. Two lichen planus pemphigoides sera, in addition, reacted with the immunodominant antigenic region associated with bullous pemphigoid. In conclusion, there are now five bullous diseases that are associated with an autoimmune response to BP180: bullous pemphigoid; pemphigoid/herpes gestationis; cicatricial pemphigoid; linear immunoglobulin A disease; and lichen planus pemphigoides. In addition, we have identified a novel epitope within the BP180 NC16A domain, designated MCW-4, that appears to be uniquely recognized by sera from patients with lichen planus pemphigoides.

Adult↗
PubMed2006

Clinical and pathological study of lichen-planus-like keratosis in China.

Lichen-planus-like keratosis is usually diagnosed pathologically; rarely, a definitive diagnosis can be made grossly in the clinic. Only a few cases of lichen-planus-like keratosis have been reported in China. The purpose of this study was to investigate the clinical and pathological features of lichen-planus-like keratosis in China. Fifty cases of lichen-planus-like keratosis patients diagnosed pathologically during a 5-year period in our clinic were analyzed. Clinical features were recorded. Sectioned specimens were subjected to hematoxylin and eosin staining to observe pathological changes. Results showed that there were 34 males and 16 females (ratio 2:1) with an average age of 61.2 years. Most of the lesions were single papules or plaques with rough surfaces. They were distributed on the face, larger than 1 cm, and dark red to brown in color. Only one case (2%) was considered to be lichen-planus-like keratosis clinically. By hematoxylin and eosin staining, solar lentigo and solar elastosis could be found in 68% and 32% of lichen-planus-like keratosis lesions, respectively. Eosinophil (42%) and plasma cell (36%) infiltration was also found frequently. Exoerythrocytes could be detected in 50% of the cases. Lichen-planus-like keratosis is not uncommon in clinical practice in China, the diagnosis of lichen-planus-like keratosis should be made by a combination of clinical manifestations and pathological changes. It is better to classify lichen-planus-like keratosis as a benign skin tumor. More attention should be paid to lichen-planus-like keratosis in China.

Aged↗
PubMed2001

Distribution of transforming growth factor-beta isoforms TGF-beta 1, TGF-beta 2 and TGF-beta 3 and vascular endothelial growth factor in vulvar lichen sclerosus.

OBJECTIVE: To study the distribution of transforming growth factor beta (TGF-beta) isoforms TGF-beta 1, TGF-beta 2 and TGF-beta 3 and vascular endothelial growth factor (VEGF) in vulvar lichen sclerosus. STUDY DESIGN: Biopsies were obtained from 10 patients with vulvar lichen sclerosus, snap frozen and stained with polyclonal antibodies to TGF-beta 1, TGF-beta 2, TGF-beta 3 and VEGF. Control tissues used were uninvolved thigh tissue from two of the lichen sclerosus patients and normal vulvar tissue obtained from eight patients during gynecologic procedures. Two specimens of morphea were also examined. RESULTS: Weak TGF-beta 1 staining was demonstrated in the epidermis of all the lichen sclerosus, morphea, thigh and five of the eight normal vulvar specimens. Slight increase in TGF-beta 1 staining was seen in the upper and middermis in 6 of the 10 lichen sclerosus specimens and in the morphea specimens as compared to the control tissue, and this staining was localized within cells. TGF-beta 2 staining was present throughout the epidermis in all the normal thigh, normal vulva, lichen sclerosus and morphea specimens. TGF-beta 2 staining was increased within cells in the upper and middermis of the lichen sclerosus and morphea specimens. TGF-beta 3 staining occurred in the basal half of the epidermis of all the control, lichen sclerosus and morphea specimens, and only slight upper dermal staining of a few individual cells was seen in 3 of the 10 lichen sclerosus specimens. VEGF staining was similar in the normal tissues, lichen sclerosus and morphea. CONCLUSION: These results suggest that TGF-beta may.

Biopsy↗
PubMed2002

Biomonitoring air pollution with the desert lichen Ramalina maciformis.

To investigate the environmental impact of anthropogenic activity in the Negev Desert, we monitored the following in order to determine the physiological integrity of the epilithic fruticose lichen Ramalina maciformis: (1) production of ethylene; (2) potential quantum yield of photosystem II expressed as chlorophyll fluorescence ratio Fv/Fm; and (3) electrolyte leakage of cell membranes in terms of electric conductivity. The degree of pollution was assessed by measuring the amounts of B, Cd, Co, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Sr and Zn in the lichen thallus. Some of the lichen-carrying stones collected in the relatively unpolluted control site were relocated on the same hill, to test the possible impact of relocation. An additional amount of lichen-carrying stones was marked as controls. The greater part of the lichen-carrying stones was transferred to 10 biomonitoring sites in and around Ramat Hovav, an industrial area in the Negev Desert, Israel. Transplanted lichen in polluted sites contained higher amounts of mineral elements than lichens in the control site after an exposure period of 7 months. Statistical analysis revealed positive correlation of ethylene production and Ni content, negative correlation of Fv/Fm ratios and B, Cu, Mn, Na, Ni, Sr and Zn, and positive correlation of electric conductivity and B, Mn, Ni and Sr. Both elemental content and physiological alterations in transferred samples of R. maciformis point to a high degree of contamination in Ramat Hovav. The present study suggests that the lichen R. maciformis should be classified as a sensitive species endangered by anthropogenic activity in the desert. Furthermore, this lichen species is likely to be suitable as a bioindicator of pollution in other parts of the Negev Desert. Ethylene production and electric conductivity as parameters of lichen-vitality, indicated stress in 5 of the 12 biomonitoring sites (42%) and may therefore be considered as more sensitive than the Fv/Fm ratio, which indicated stress in 3 of the 12 sites (25%).

Journal Article↗
PubMed1997

Lichen sclerosus.

Lichen sclerosus is commonly seen in middle-aged and elderly women but it affects both sexes, can occur at any age and anywhere on the body and has been reported in most races. Its aetiology is uncertain but there is an increased incidence of auto-immune antibodies in lichen sclerosus and an association with auto-immune disease such as vitiligo, thyroid disease and alopecia areata. Lichen sclerosus has been observed in different generations of a family but no consistent genetic pattern has emerged. Lichen sclerosus typically affects the anogenital region and presents with an intractable 'burning' pruritus. Extragenital lesions do not itch. Oral lesions occur in lichen sclerosus and may resemble lichen planus. Lichen sclerosus exhibits the isomorphic or Koebner phenomenon. The literature supports the view that lichen sclerosus is not a precancerous lesion but there is a significant association with vulval squamous cell carcinoma. Patients with inactive, treated lichen sclerosus should be reviewed annually. The treatment of choice of uncomplicated genital lichen sclerosus is a topical steroid of a potent or super-potent category. In males, circumcision may be indicated if topical measures are unsuccessful. In women, surgery is considered predominantly for cancer confirmed by tissue examination.

Journal Article↗
PubMed1999

The lichen rock tripe (Lasallia pustulata) as survival food: effects on growth, metabolism and immune function in Balb/c mice.

The present study was performed to investigate whether the lichen rock tripe (Lasallia pustulata) can be used as food during survival situations. The effects of 30% lichen supplementation given to female Balb/c mice were studied on growth rate, metabolism and immune functions. After 3 weeks on this diet, it was found that the lichen supplementation did not affect the growth rate or the well-being of the animals. The growth rate tended to be higher in the lichen group when compared to control mice. Food consumption was similar in both groups, but with a trend towards slightly higher intake (12%) in the lichen group. The heart, liver, kidney and lymphoid organ (spleen and thymus) weights were not affected by the lichen. Histological hematoxylin eosin staining showed that all these organs were normal. Plasma glucose levels were unchanged, but plasma urea levels decreased by 24% (p < 0.05) with the lichen diet. Red and white blood cells and the number of lymphoid cells in the thymus and spleen were normal. The activity of thymocytes and spleen T-lymphocytes were not affected by the lichen diet, but spontaneous cell-mediated cytotoxicity (NK cells) tended (n.s.) to increase and spleen B-lymphocyte activity increased by 40% (p < 0.05). This study shows that the lichen rock tripe has immune stimulating effects important for host defence reactions and can be used as food in survival situations without any adverse effects on the metabolism.

Animals↗
PubMed1998

[Lichen planopilaris simulating postmenopausal frontal fibrosing alopecia (Kossard)].

A 68-year old woman presented with a frontal fibrosing alopecia and lesions of the buccal mucous membranes typical for lichen planus. Postmenopausal frontal fibrosing alopecia (PFFA) has recently been described by Kossard as a distinct entity characterized by progressive recession of the frontotemporal and parietal hair margins leading to permanent alopecia in the form of a symmetrical band-like area of scanning in postmenopausal women. The histology (perifollicular lymphocytic infiltration and fibrosis, increase of apoptosis of hair follicle keratinocytes) is indistinguishable from that of lichen planopilaris. The localization and age- and sex-related characteristics of PFFA are not sufficient to delineate it as a discrete entity from lichen planopilaris. Our observation of oral lichen planus in a postmenopausal woman with frontal fibrosing alopecia points to the possibility that PFFA actually may represent a variant of lichen planopilaris with a predilection for the frontotemporal hairline. Other variants of lichen planopilaris include multifocal lichen planopilaris, disseminated lichen planopilaris (Lassueur-Graham-Little syndrome), lichenoid pseudopelade, and any combination of these ("mixed type"). An effective therapy of PFFA is not known. Also, treatment of lichen planopilaris forms in which fibrosis predominates over inflammation is similarly problematic, but the natural course of these diseases seems to be self-limited.

Aged↗
PubMed2000

Phototolerance of lichens, mosses and higher plants in an alpine environment: analysis of photoreactions.

Adaptation to excessive light is one of the requirements of survival in an alpine environment particularly for poikilohydric organisms which in contrast to the leaves of higher plants tolerate full dehydration. Changes in modulated chlorophyll fluorescence and 820-nm absorption were investigated in the lichens Xanthoria elegans (Link) Th. Fr. and Rhizocarpon geographicum (L.) DC, in the moss Grimmia alpestris Limpr. and the higher plants Geum montanum L., Gentiana lutea L. and Pisum sativum L., all collected at altitudes higher than 2000 m above sea level. In the dehydrated state, chlorophyll fluorescence was very low in the lichens and the moss, but high in the higher plants. It increased on rehydration in the lichens and the moss, but decreased in the higher plants. Light-induced charge separation in photosystem II was indicated by pulse-induced fluorescence increases only in dried leaves, not in the dry moss and dry lichens. Strong illumination caused photodamage in the dried leaves, but not in the dry moss and dry lichens. Light-dependent increases in 820-nm absorption revealed formation of potential quenchers of chlorophyll fluorescence in all dehydrated plants, but energy transfer to quenchers decreased chlorophyll fluorescence only in the moss and the lichens, not in the higher plants. In hydrated systems, coupled cyclic electron transport is suggested to occur concurrently with linear electron transport under strong actinic illumination particularly in the lichens because far more electrons became available after actinic illumination for the reduction of photo-oxidized P700 than were available in the pool of electron carriers between photosystems II and I. In the moss Grimmia, but not in the lichens or in leaves, light-dependent quenching of chlorophyll fluorescence was extensive even under nitrogen, indicating anaerobic thylakoid acidification by persistent cyclic electron transport. In the absence of actinic illumination, acidification by ca. 8% CO2 in air quenched the initial chlorophyll fluorescence yield Fo only in the hydrated moss and the lichens, not in leaves of the higher plants. Under the same conditions, 8% CO2 reduced the maximal fluorescence yield Fm strongly in the poikilohydric organisms, but only weakly or not at all in leaves. The data indicate the existence of deactivation pathways which enable poikilohydric organisms to avoid photodamage not only in the hydrated but also in the dehydrated state. In the hydrated state, strong nonphotochemical quenching of chlorophyll fluorescence indicated highly sensitive responses to excess light which facilitated the harmless dissipation of absorbed excitation energy into heat. Protonation-dependent fluorescence quenching by cyclic electron transport, P700 oxidation and, possibly, excitation transfer between the photosystems were effectively combined to produce phototolerance.

Adaptation, Physiological↗
PubMed1998

Preliminary investigation of the association of oral lichen planus and hepatitis C.

OBJECTIVE: The aim of this investigation was to determine if an association exists between hepatitis C virus and oral lichen planus. STUDY DESIGN: Three groups of subjects were selected: 505 patients with hepatitis C virus infection (group 1), 100 patients with oral lichen planus (group 2), and a randomly selected control group (age- and gender-matched) of 100 healthy subjects (group 3). The prevalence of oral lichen planus was determined in groups 1 and 3, and the prevalence of hepatitis C virus infection was established in groups 2 and 3. RESULTS: The prevalence of oral lichen planus was 3.36% (n = 17) in group 1 and 1% (n = 1) in the control group; the prevalence of hepatitis C virus infection was 23% (n = 23) in group 2, and 5% (n = 5) in the control group. No significant differences were observed in the incidence of oral lichen planus in group 1 between those patients who received interferon and those who did not. The 17 patients in group 1 who manifested oral lichen planus and hepatitis C virus infection simultaneously exhibited a marked tendency to have only reticular lesions (70.6%), with involvement of the buccal mucosa in 88.2% of these patients, the tongue in 29.4%, and the gingiva in 11.8%. Analyzing a randomized subgroup of 143 patients from group 1 (subgroup 1) that was matched by age and gender with groups 2 and 3, we found that the incidence of oral lichen planus in patients with hepatitis C virus infection (subgroup 1) was greater than in the control group (5.59% vs 1%), though this was not statistically significant (chi2 = 0.119; p = 0.06). In contrast, group 2 exhibited a statistically significant higher incidence of hepatitis C virus infection (23%) than the controls (5%; chi2 = 0.259, p = 0.0002). CONCLUSIONS: The prevalence of hepatitis C virus infection in patients with oral lichen planus was greater than in the control series. In our opinion this observation warrants the investigation of potential concomitant hepatitis C virus infection in patients with oral lichen planus.

Candidiasis, Oral↗
PubMed2006

Multi-element including rare earth content of lichens, bark, soils, and waste following industrial closure.

The fate of rare earth and other rare elements entering the environment is largely unknown. The lichen Hypogymnia physodes was transplanted over a 40 km long transect centered on a major metallurgical waste dump close to the Zlatna town center two weeks after smelter closure. Lichens, bark, soil, and waste dump materials were analyzed for 56 elements (including REE). Lichen and bark multi-element compositions were alike, reflecting fixation of elements of environmental concern and the ability for tree canopies to concentrate substances leading to enhanced deposition to both lichens and bark. Higher REE enrichment in lichens than in soil confirm efficient fixation in lichens. The negative europium anomaly in lichens and soil, similar to that in upper crust, confirm a strong crustal influence on lichen signatures across the transect area. Multi-element analysis supports the view that epiphytic lichens, unlike trees, are not influenced by lower groundwater, and they are excellent indicators for REE and other rare elements entering the surface environment, difficult to detect by conventional means.

Air Pollutants, Occupational↗
PubMed2000

Mercury and other elements in lichens near the INA Naftaplin gas treatment plant, Molve, Croatia.

This paper describes the use of epiphytic lichens as bioindicators for spatial monitoring of mercury and other elements in air near the natural gas treatment facilities at Molve, Croatia. It is well known that at this location the concentration of mercury in natural gas is very high and therefore it has to be removed from natural gas before further processing in order to prevent technological and environmental problems. In order to monitor the efficiency of an industrial facility for removal of mercury from natural gas, mercury measurements in air and lichens were performed during 9 months in 1997/1998. In situ lichens Parmelia sulcata, Xantoria parientina and Hypogymnia physodes and transplanted lichen species Hypogymnia physodes were used. A good correlation between mercury concentrations in air and lichens was found. The concentrations of barium and bromium were also significantly elevated in transplanted lichens, most probably related to technological process at the gas treatment plant and/or other geological factors. It was confirmed that lichens can successfully be used as bioindicators, provided a careful experiment is designed, particularly the amount of lichens transplanted, the duration of exposure and the initial levels and homogeneity of transplanted lichens.

Croatia↗