French guidelines for the management of oral lichen planus (excluding pharmacological therapy)

INTRODUCTION

Oral lichen is a chronic inflammatory disease for which diagnostic management and follow-up are heterogeneous given the absence of specific guidelines in France. Our objective was to develop French multidisciplinary guidelines for the management of oral lichen.

MATERIALS AND METHODS

Working groups from the Groupe d'Etude de la Muqueuse Buccale (GEMUB) formulated a list of research questions and the corresponding recommendations according to the "formal consensus" method for developing practice guidelines. These recommendations were submitted to a group of experts and the degree of agreement for each recommendation was assessed by a scoring group.

RESULTS

Twenty-two research questions, divided into 3 themes (nosological classification and initial assessment, induced oral lichenoid lesions, and follow-up) resulted in 22 recommendations. Initial biopsy for histology is recommended in the absence of reticulated lesions. Biopsy for direct immunofluorescence is recommended for ulcerated, erosive, bullous types and for diffuse erythematous gingivitis. Management should include a periodontal and dental check-up, and investigation for extra-oral lesions. Hepatitis C testing is recommended only if risk factors are present. Definitions, triggering factors and the management of "induced oral lichenoid lesions" were clarified. Oral lichen must be monitored by a practitioner familiar with the disease at least once a year, using objective tools.

CONCLUSION

This formalised consensus of multidisciplinary experts provides clinical practice guidelines on the management and monitoring of oral lichen.

Oral Kaposi Sarcoma in two patients living with HIV despite sustained viral suppression: New clues

Kaposi sarcoma (KS) etiologically linked to Kaposi sarcoma-associated herpesvirus (KSHV) is the most common HIV associated cancer despite the generalization of antiretroviral therapy. Head, neck, and especially oral cavity are common and specific sites for lesions. Those oral lesions contain a high viral load of KSHV virus and are one of the signs of disease severity. The development of KS in HIV-infected patients is classically described in case of low CD4 count, but recently reported cases revealed oral KS despite a robust CD4 count, such observations being possibly linked to interactions between periodontal germs and the oncogenic KSHV virus. We present two cases of KS location on the oral mucosa in HIV patients with gingival inflammation despite efficient antiretroviral treatment and immune restoration. Those cases suggest that the diagnosis of oral KS lesions should be considered by oral surgeons, dermatologists, and infectious specialists, when managing any suspicious lesion in an HIV patient, even with undetectable HIV viral loads, or in a seronegative patient with unprotected sexual activity.

Key words:Kaposi Sarcoma, KSHV, HIV infection, CD4 count, oral lesion, oral cancer, periodontal pathogens.

Cognitive appraisal in fish: stressor predictability modulates the physiological and neurobehavioural stress response in sea bass

The role of cognitive factors in triggering the stress response is well established in humans and mammals (aka cognitive appraisal theory) but very seldom studied in other vertebrate taxa. Predictability is a key factor of the cognitive evaluation of stimuli. In this study, we tested the effects of stressor predictability on behavioral, physiological and neuromolecular responses in the European sea bass (Dicentrarchus labrax). Groups of four fish were exposed to a predictable (signalled) or unpredictable (unsignalled) stressor. Stressor predictability elicited a lower behavioural response and reduced cortisol levels. Using the expression of immediate early genes (c-fos, egr-1, bdnf and npas4) as markers of neuronal activity, we monitored the activity of three sea bass brain regions known to be implicated in stressor appraisal: the dorsomedian telencephalon, Dm (putative homologue of the pallial amygdala); and the dorsal (Dld) and ventral (Dlv) subareas of the dorsolateral telencephalon (putative homologue of the hippocampus). The activity of both the Dm and Dlv significantly responded to stressor predictability, suggesting an evolutionarily conserved role of these two brain regions in information processing related to stressor appraisal. These results indicate that stressor predictability plays a key role in the activation of the stress response in a teleost fish, hence highlighting the role of cognitive processes in fish stress.

Risk-taking behaviour variation over time in sea bass Dicentrarchus labrax: effects of day-night alternation, fish phenotypic characteristics and selection for growth

Differences in bold and shy personality on sea bass Dicentrarchus labrax were investigated between a population (wild) produced from wild-brood fish and a population (selected) produced from selected-brood fish. During the experiment (112 days), fish were reared under self-feeding condition to characterize the feeding behaviour of each individual fish. Three risk-taking tests (T1, T2 and T3 of 24 h with day-night alternation) were carried out at >1 month intervals on 180 fish of each strain in order to monitor D. labrax behaviour over time and in relation to the light:dark period. A risk-taking score was evaluated via a preference choice between a safe zone (without food) and a risky zone (potentially with food) by recording the number and the duration of individual passages through an opening in an opaque divider. Results showed that fish performed passages preferentially during the night period and that wild fish were generally bolder than selected fish during T1 and T2 but showed a decrease in risk taking during T3, contrary to selected fish which showed a constant increase in their risk-taking behaviour. The phenotypic characteristics of the bold fish were different in the two strains: wild bold fish were the smallest within the wild strain and selected bold fish presented the higher growth rate within the selected strain. For both strains, these bold fish were also generally characterized by a high feed-demand activity. Fish hunger state thus seemed to be the highest motivation for risk-taking behaviour under the present conditions. Furthermore, behavioural variations over tests such as higher risk taking (number of passages) and faster exploratory responses (higher score emergence) could be interpreted as relevant indicators of the learning process and habituation. According to the results, however, no real difference in coping strategy between strains could be observed at this first stage of domestication and selection.

Diversity and specificity of ectomycorrhizal fungi retrieved from an old-growth Mediterranean forest dominated by Quercus ilex

We analysed the ectomycorrhizal (ECM) fungal diversity in a Mediterranean old-growth Quercus ilex forest stand from Corsica (France), where Arbutus unedo was the only other ECM host. On a 6400 m2 stand, we investigated whether oak age and host species shaped below-ground ECM diversity. Ectomycorrhizas were collected under Q. ilex individuals of various ages (1 yr seedlings; 3-10 yr saplings; old trees) and A. unedo. They were typed by ITS-RFLP analysis and identified by match to RFLP patterns of fruitbodies, or by sequencing. A diversity of 140 taxa was found among 558 ectomycorrhizas, with many rare taxa. Cenococcum geophilum dominated (35% of ECMs), as well as Russulaceae, Cortinariaceae and Thelephoraceae. Fungal species richness was comparable above and below ground, but the two levels exhibited < 20% overlap in fungal species composition. Quercus ilex age did not strongly shape ECM diversity. The two ECM hosts, A. unedo and Q. ilex, tended to share few ECM species (< 15% of the ECM diversity). Implications for oak forest dynamics are discussed.

Variation of the Hydrodynamic Polymer Layer Thickness on Solid Surfaces with Molecular Weight and Concentration

An extensive study on the determination of the 'hydrodynamic' layer thickness of polymer solutions and melt polymers was conducted with a surface force apparatus. For different concentrations and polymer molecular weights, a 'hydrodynamic layer' of fluid was detected on each solid surface which did not contribute to the flow. These thicknesses, denoted as LH, are compared to the characteristic polymer dimensions and the hydrodynamic (RH) and gyration (Rg) radii. It appears that in contrast to the molecular weight, polymer concentration has little effect on the relative hydrodynamic layer thickness (LH/2RH, LH/2Rg). Indeed, this ratio indicates that two coils of low molecular weight and one coil of high molecular weight are 'immobile' on the solid surfaces. The mechanism responsible could be entanglement of the free (unattached) chains in the bulk with immobilized chains on the surface.

[Variations in the lipid and fatty acid composition of cardiac tissue during perfusion of hearts isolated from rats on a high colza oil diet]

After perfusion, during one hour, of isolated working hearts extracted from Rats fed (60 days) with diet containing 15% of rapeseed oil, we have found a decrease of triglycerides and phosphatidic-cardiolipin fractions, particularly of fractions containing erucic acid. In contrast with this finding, lipids and phospholipids of hearts from Rat feed with peanut oil is not decreased and fatty acid composition slightly altered.