Search PubMed⌕ Search

Biomedical subjects

Johannes Ring

Publications and source records attributed to Johannes Ring.

85 records · Page 5Linked to original sources
PubMed2002

Permeability barrier disruption increases the level of serine palmitoyltransferase in human epidermis.

Sphingolipids play an important role in the homeostasis and barrier function of human stratum corneum. A disturbance of sphingolipid formation is supposed to be a crucial factor for the increased transepidermal water loss in common skin diseases like atopic eczema or psoriasis. The key enzyme for de novo sphingolipid synthesis is serine palmitoyltransferase, which consists of two different subunits, named LCB1 and LCB2 proteins. In order to investigate the induction of LCB2 synthesis in human epidermis, skin barrier disruption was performed by tape stripping on the forearm of healthy volunteers enough to obtain a 3-4-fold increase in transepidermal water loss. Skin punch biopsies were taken before and 0.5, 2, 4, and 8 h after tape stripping by each volunteer to measure LCB2 at the mRNA level. Additional biopsies taken before and 12 h after tape stripping were used to evaluate LCB2 at the protein level. Our results show that 0.5 and 2 h after tape stripping the LCB2 mRNA expression was decreased compared to control in all cases. A significant increase in LCB2 mRNA expression was detectable 4 h after barrier disruption, with individual variations; no further increase was detectable 8 h after tape stripping. Immunohistochemical analysis 12 h after barrier disruption showed increased LCB2 immunolocalization in the inner epidermis, whereas in the outer epidermis it was similar to control. LCB2 mRNA expression preceded the expression of the corresponding protein by 4-8 h. Our findings support the concept that an increase in transepidermal water loss is an obligatory trigger for the upregulation of serine palmitoyltransferase mRNA expression in humans.

Acyltransferases↗
PubMed2002

Lipid mediators from pollen act as chemoattractants and activators of polymorphonuclear granulocytes.

BACKGROUND: Under natural exposure conditions, pollen grains function as allergen carriers that release allergens from internal binding sites on contact with the aqueous phase of mucosa membranes. In addition, we recently demonstrated that pollen are a rich source of eicosanoid-like mediators, which are rapidly released on contact with the aqueous phase. OBJECTIVE: The current study was designed to characterize the biochemical nature of pollen-derived lipid mediators in more detail and to delineate their biologic activity on polymorphonuclear granulocytes (PMNs). METHODS: Aqueous and lipid extracts from Phleum pratense L and Betula alba L pollen were analyzed by means of HPLC. PMNs were exposed to aqueous extracts or lipid fractions from pollen or to HPLC-purified lipid mediators identified in pollen extracts. Effects on PMNs were tested with transwell migration, calcium mobilization, and surface expression of CD11b. RESULTS: Aqueous pollen extracts (APEs) contained predominantly monohydroxylated products derived of linoleic acid and linolenic acid. In chemotaxis assays PMNs displayed significant migration to APEs. Lipid extracts from pollen and the HPLC fraction containing 13-hydroxy-octadecadienoic acid/hydroxy-linoleic acid and 13-hydroxy-octadecatrienoic acid/hydroxy-linolenic acid induced migratory responses, although to a lesser degree than the APEs. In addition, APE, as well as lipid, extracts induced PMN activation, as documented by means of calcium mobilization and upregulation of CD11b. CONCLUSION: Pollen grains release mediators that recruit and activate PMNs in vitro. Similar mechanisms may be effective in vivo, suggesting that pollen-derived lipid mediators may act as adjuvants in the elicitation phase of allergic reactions.

Cell Movement↗
PubMed2002

Topical tacrolimus (FK506) and mometasone furoate in treatment of dyshidrotic palmar eczema: a randomized, observer-blinded trial.

BACKGROUND: Dyshidrotic palmoplantar eczema is a frequent disease often running a chronic relapsing course. Topical glucocorticosteroids form the mainstay of therapy, and alternatives are urgently warranted. OBJECTIVE: This study was performed to compare the efficacy of tacrolimus (FK506) 0.1% ointment and mometasone furoate 0.1% ointment in the treatment of dyshidrotic palmoplantar eczema. METHODS: Sixteen patients were included in the study after a randomized, observer-blind, intrapersonal comparison protocol. After a 2-week washout period, the active treatment phase amounted to 4 weeks with twice-daily topical application of test substances and additional use of emollients at will. Thereafter, patients were monitored at weekly intervals up to 8 weeks. RESULTS: The dyshidrotic area and severity index showed a more than 50% reduction of baseline values after 2 weeks of active treatment both for FK506 (P =.003) and mometasone furoate (P =.022) in palmar areas. After active treatment, a nonsignificant increase in the dyshidrotic area and severity index was seen with FK506 treated areas. Fourteen of 16 patients had recurring symptoms requiring further therapy within 3 weeks after the active treatment phase. CONCLUSION: Treatment with FK506 offers the possibility for rotational therapy with mometasone furoate in long-standing cases of chronic dyshidrotic palmar eczema.

Administration, Cutaneous↗
PubMed2002

Multiple chemical sensitivity (MCS) and others: allergological, environmental and psychological investigations in individuals with indoor air related complaints.

Clinical observations point to an expanding group of individuals attributing hypersensitivity phenomena to indoor air pollution. It was the aim of this study to characterize such subjects by an interdisciplinary approach. Sixty-five individuals, recruited by a public campaign, were studied by a thorough allergological examination and a structured psychological interview. Measurements of common indoor pollutants in the air and in the dust were performed in rooms of several selected patients. Forty-two patients (65%) revealed a sensitization to common allergens, out of these 32 (49%) to house dust mites. Thirty-eight (58%) patients showed a psychosomatic or psychotic disorder. Increased concentrations of at least one of the measured indoor air pollutants were found in 11 out of 13 investigated houses. According to these results, four groups of patients could be identified: Seventeen patients (26%) had "classic" allergic diseases treated inadequately. In 19 patients (29%) allergic diseases were superimposed by strong psychosomatic interactions. An exclusive psychosomatic or psychotic cause of the complaints was found in 19 (29%). Ten subjects (16%) had "classic" allergic diseases (e.g. allergic rhinoconjunctivitis, urticaria), however, there were additional indications of hypersensitivity reactions to components other than classical allergens. Patients presenting with hypersensitivity phenomena attributed by themselves to indoor air pollution are a heterogeneous group and need a diligent work-up including intense allergological examination. The role of increased concentrations of indoor air pollutants has to be elucidated further.

Adult↗
PubMed2002

Screening for depression in adult acne vulgaris patients: tools for the dermatologist.

BACKGROUND: Adult dermatological out patients have a 40% prevalence of psychiatric co-morbidity. If psychiatric co-morbidity is unrecognized, undetected and untreated, the consequences may be fatal. Acne is the most common skin disorder of the second and third decades of life. Acne and its treatments may cause depression. AIMS: To identify a screening tool to identify depression in adult acne patients. METHODS: The literature was reviewed to identify validated screening instruments for depressive disorders. Questionnaires studied included the Hospital Anxiety and Depression Scale (HAD), the Brief Patient Health Questionnaire (B-PHQ), the General Health Questionnaire-12 item version (GHQ-12), and the World Health Organization-5 Well Being Index (WHO-5). RESULTS: WHO-5 performed best in terms of sensitivity (0.93 for a cut-off score of 13) as well as taking least time to complete (2-5 min) and evaluate (0.5-2 min). CONCLUSIONS: WHO-5 can be recommended as part of a two-step screening process for depression in acne patients. Step 1 is the WHO-5. In the case of a positive score, step 2 is a detailed psychosocial assessment.

Acne Vulgaris↗
PubMed2002

Topical steroids under wet-wrap dressings in atopic dermatitis--a vehicle-controlled trial.

BACKGROUND: The wet-wrap dressing technique has proved to be beneficial in cases of exacerbated atopic dermatitis (AD) skin lesions. OBJECTIVE: The effect of wet-wrap dressings was investigated in a controlled trial comparing a steroid (mometasone furoate 0.1%)-containing and a steroid-free (vehicle) preparation in an in-patient comparison study. METHODS: 20 children aged 2-17 years with exacerbated AD were treated twice daily with wet-wrap dressings over a 5-day period. RESULTS: AD in treated areas significantly improved in both study arms; however, the effect was significantly better in the mometasone-treated group (p < 0.01). Transepidermal water loss improved in both arms without any significant differences. Staphylococcus aureus colonization decreased during the first 3 days of active treatment independently of the therapeutic modalities chosen. At day 5, colony counts further dropped on the steroid-treated lesions. CONCLUSION: Application of the wet-wrap dressing technique for exacerbated AD lesions is effective, combination with a topical steroid being superior to a steroid-free application without bearing the risk of a bacterial superinfection.

Administration, Topical↗
PubMedDate not supplied

Adverse drug reactions: mechanisms and assessment.

Adverse drug reactions (ADR) are an important clinical problem. They account for about 5% of all hospital admissions and cause death in approximately 0.01% of surgical patients. The mechanisms leading to ADR beyond IgE-mediated allergy are still poorly understood. The importance of chemically reactive drug metabolites and the involvement of T-lymphocytes in many drug hypersensitivity reactions have been highlighted in recent years. ADR are diagnosed on clinical grounds and the temporal relation between drug intake and the appearance of the symptoms. Allergy tests are required in the further assessment of the reaction. By means of skin tests, in vitro tests and provocation tests information about the culprit drug, the mechanism involved and possible alternatives can be obtained.

Anaphylaxis↗