Histamine suppresses epidermal keratinocyte differentiation and impairs skin barrier function in a human skin model.

BACKGROUND: Defects in keratinocyte differentiation and skin barrier are important features of inflammatory skin diseases like atopic dermatitis. Mast cells and their main mediator histamine are abundant in inflamed skin and thus may contribute to disease pathogenesis. METHODS: Human primary keratinocytes were cultured under differentiation-promoting conditions in the presence and absence of histamine, histamine receptor agonists and antagonists. The expression of differentiation-associated genes and epidermal junction proteins was quantified by real-time PCR, Western blot, and immunofluorescence labeling. The barrier function of human skin models was tested by the application of biotin as tracer molecule. RESULTS: The addition of histamine to human keratinocyte cultures and organotypic skin models reduced the expression of the differentiation-associated proteins keratin 1/10, filaggrin, and loricrin by 80-95%. Moreover, the addition of histamine to skin models resulted in the loss of the granular layer and thinning of the epidermis and stratum corneum by 50%. The histamine receptor H1R agonist, 2-pyridylethylamine, suppressed keratinocyte differentiation to the same extent as did histamine. Correspondingly, cetirizine, an antagonist of H1R, virtually abrogated the effect of histamine. The expression of tight junction proteins zona occludens-1, occludin, claudin-1, and claudin-4, as well as that of desmosomal junction proteins corneodesmosin and desmoglein-1, was down-regulated by histamine. The tracer molecule biotin readily penetrated the tight junction barrier of skin cultures grown in the presence of histamine, while their diffusion was completely blocked in nontreated controls. CONCLUSIONS: Our findings suggest a new mechanism by which mast cell activation and histamine release contribute to skin barrier defects in inflammatory skin diseases.

Freckles and solar lentigines have different risk factors in Caucasian women.

BACKGROUND: To date, few epidemiological data on the relationships between solar lentigines, freckles and behavioural and constitutional risk factors in Caucasian populations exist. OBJECTIVES: To investigate the potential impact of behavioural and phenotypic variables, as well as the MC1R genetic background, on the history of facial freckles and the severity of solar lentigines in Caucasian women. METHODS: The severity of solar lentigines was graded from facial digital images of 523 French middle-aged women by a dermatologist and summarized by a score afterwards. The history of facial freckles was assessed and the sun-exposure behaviour was characterized using a six-category typology. Risk factors including MC1R polymorphism were evaluated using logistic regression models. RESULTS: Two constitutive host factors were found to be independently associated with a history of facial freckles: frequent sunburns and the presence of diminished function variants of the MC1R gene. In addition to age, five factors were independently associated with solar lentigines: constitutive host factors (dark skin colour and tanning capacity), a history of freckles, sun-exposure behaviour and current intake of oral contraceptive or progestogen treatments. CONCLUSION: These results strengthen the hypothesis that solar lentigines are markers of photoaging, whereas freckles are mainly determined by genetic factors. The finding that hormonal treatment is associated with a higher risk for solar lentigines merits further investigations.

[MC1R polymorphisms and facial photoaging]. / Polymorphismes du MC1R et photovieillissement du visage.

BACKGROUND: The objective of this study was to assess the association between melanocortin-1 receptor (MC1R) variants and the severity of facial skin photoaging. METHODS: The study population comprised 530 French middle-aged women between 44 and 70 years. A trained dermatologist graded the severity of facial skin photoaging from photographs using Larnier's global scale. Logistic regressions were performed to assess the influence of MC1R polymorphism on severe photoaging (grades 1-3 vs. 4-6), with adjustment for possible confounders (demographic and phenotypic data, and sun exposure intensity). RESULTS: Overall, 35% of the women were wild-type homozygotes, 49% had one variant, 15% had two variants, and 1% had at least one rare variant. After adjustment for possible confounders, the presence of two major diminished function variants was found to be a risk factor for photoaging (adjusted odds ratio=5.61; 95% confidence interval [1.43-21.96]). DISCUSSION: Our results suggest that genetic variations of MC1R are important determinants for severe photoaging.

[Deformity-associated treatment of the hallux valgus complex]. / Deformitätsassoziierte Behandlung des Hallux-valgus-Komplexes.

Hallux valgus represents a combined deformity with malpositioning of the big toe in the metatarsophalangeal joint and metatarsal splaying due to metatarsus primus varus formation. It is defined on the basis of joint condition of the metatarsophalangeal and tarsometatarsal (TMT) joints, the extent and congruence or incongruence of malposition, mobility of the metatarsophalangeal joint and TMT stability. Basic resection appears to be indicated only in exceptional cases. Depending on the degree of severity, deformities can be corrected by means of distal, diaphyseal or proximal osteotomies and TMT arthrodeses. Any correction requires the use of subtle soft tissue surgery with recentering of the tendon, tightening of the medial capsule and abductor hallucis and releasing the lateral capsule. A check-list-like analysis of hallux valgus deformity helps determine the ideal procedure and avoid over- or under-treatment.

Airway inflammation induced after allergic poly-sensitization can be prevented by mucosal but not by systemic administration of poly-peptides.

BACKGROUND: Patients with multiple sensitizations require alternative forms of treatment, as the efficacy of conventional immunotherapy is unsatisfactory. OBJECTIVE: In the present study, we sought to compare the efficacy of a subcutaneously (s.c.) and a mucosally applied polyvalent vaccine to reduce allergic immune responses within airway and lung tissues. METHODS: Female BALB/c mice were intraperitoneally immunized with recombinant (r)Bet v 1, rPhl p 1 and rPhl p 5, followed by an aerosol challenge of birch and phleum pollen extract. For tolerance induction, either a mixture of the immunodominant peptides or a hybrid peptide of the respective antigens was s.c. injected or intranasally applied before poly-sensitization. RESULTS: Mucosal but not systemic pre-treatment with poly-peptides led to significant suppression of eosinophils and IL-5 production in bronchoalveolar lavages, as well as IL-5, IL-4, IL-13 and eotaxin levels in lung cell cultures. Lung histology showed a clear reduction of cellular infiltration and mucus production only in intranasally pre-treated mice. In accordance, also the systemic immune response, characterized by IgE-dependent basophil degranulation and IL-4 levels in vitro, was significantly reduced by mucosal antigen application, but only marginally influenced by subcutaneous pre-treatment. Both treatment routes led to up-regulated CTLA4 expression in splenocytes, whereas only after mucosal pre-treatment Foxp3 expression levels were enhanced in lung CD3(+) T cells. Furthermore, intranasal but not subcutaneous application of the peptides enhanced IL-10 levels in the lungs, indicating regulatory mechanisms operating in local tolerance induction. CONCLUSION: Mucosal application of peptides is superior to systemic application in preventing both local and systemic poly-allergic T helper2 immune responses, suggesting mucosal tolerance induction as an attractive strategy for the primary and secondary prevention of allergic multi-sensitization and lung pathology.

Alterations in antral cytokine gene expression in peptic ulcer patients during ulcer healing and after Helicobacter pylori eradication.

Earlier studies have shown that the antral immune response in Helicobacter pylori infection has a mixed Th1-Th2-T-regulatory profile. After eradication, a chronic inflammation remains in some patients, but a follow-up study with a comprehensive cytokine profile in has not previously been published. Twelve patients with H. pylori positive peptic ulcer disease (five antral and seven duodenal) were enrolled and cytokine gene expressions in antral biopsies were determined (1) at entry, (2) after resolving the ulcer with proton pump inhibitor (PPI) treatment and (3) after eradication. The second endoscopy was performed 4 weeks after ending the PPI treatment, and the third endoscopy was performed after a mean of 10 months after eradication. Inflammation was graded according to the updated Sydney system. Interleukin (IL)1beta, IL8, IL12A, IL18, TNFalpha, IFNgamma, IL4, IL6 and IL10 expression levels were analysed by real-time RT-PCR. Mixed mononuclear and neutrophil infiltrates were seen at entry and after ulcer healing. After eradication, low-grade mononuclear infiltrates were found. The cytokine expression levels after ulcer healing (H. pylori positive gastritis) were not significantly different from the levels at entry (ulcer). After eradication, attenuation of the Th1 cytokines except for TNFalpha and a persisting increase of IL4 levels were observed, whereas the IL10 expression was markedly reduced. The present data did not indicate a specific ulcer promoting cytokine gene regulation profile. However, after eradication a chronic low-grade inflammation was seen with reduced Th1, prolonged Th2 and disappearance of the T-regulatory response.

High tissue factor-expressing human monocytes carry low surface CD36: application to intersubject variability.

BACKGROUND: The 'high and low responder' phenomenon describes an intersubject variability in mononuclear cell (MNC) prothrombotic reactivity to lipopolysaccharide (LPS) stimulation. Because alterations in surface CD36 expression in monocytes were associated with impaired monocyte function, we studied the relationship between the levels of surface CD36 presentation and the prothrombotic reactivity of monocytes from high-responder (HR) and low-responder (LR) individuals. METHODS AND RESULTS: The relationship between levels of tissue factor (TF) expression and surface CD36 presentation in MNCs from HR individuals (n = 7) and LR individuals (n = 8) was investigated. Resting MNCs from HR individuals contained significantly more TF mRNA but levels of TF antigen and procoagulant activity similar to MNCs from LR individuals. Resting CD14+ MNCs from HR individuals expressed significantly lower surface CD36, as mean fluorescence intensities (MFIs) were 70.4 +/- 6.3 vs. 132.0 +/- 14.5 arbitrary units (AU) in HR and LR individuals, respectively. MFI from surface TF negatively correlated with surface CD36 in the population of resting (r = -0.598, P = 0.031) and LPS-stimulated (r = -0.672, P = 0.009) CD14+ cells. LPS-stimulated MNCs from HR individuals contained significantly more TF in a surface pool (2079 +/- 199 vs. 786 +/- 57 AU) along with higher TF procoagulant activity (57.3 +/- 15.2 vs. 21.1 +/- 4.5 mU 10(6) cells(-1)) as compared with LR individuals. CD14+ MNCs from HR individuals expressed less surface CD36 during a 2-h LPS challenge. CONCLUSIONS: A novel phenotype of monocytes characterized by high TF and low CD36 presentation could be further developed for use as a marker for detection of HR individuals prone to developing prothrombotic conditions.

Selecting and deselecting imatinib-resistant clones: observations made by longitudinal, quantitative monitoring of mutated BCR-ABL.

Resistance to imatinib during the treatment of chronic myeloid leukaemia (CML) is frequently associated with point mutations in the ABL gene encoding the ATP binding region likely to cause disease relapse. Early diagnosis and monitoring of these mutations may be important in order to prevent rapid expansion of resistant clones. We describe a quantitative mutation-specific PCR assay based on the readily available Taqman platform. Selectivity for the mutated target is conferred by mutation-specific primers destabilised by additional mismatches. The assay can be carried out in parallel to standard BCR-ABL quantification and is therefore more quickly compared to standard sequencing procedures. The sensitivity of the assay reaches 0.1%. It also allows for quantitative assessment of mutated clones. By analysing sequential samples of resistant subjects, we show how mutated clones were selected, maintained or deselected depending on the individual treatment setting. The high sensitivity and practical merits of this method makes it a good candidate for prospective molecular surveillance of patients at high risk for imatinib resistance.

Safety and efficacy of the combination of pegylated interferon-α2b and dasatinib in newly diagnosed chronic-phase chronic myeloid leukemia patients.

Dasatinib (DAS) and interferon-α have antileukemic and immunostimulatory effects and induce deep responses in chronic myeloid leukemia (CML). We assigned 40 newly diagnosed chronic-phase CML patients to receive DAS 100 mg o.d. followed by addition of pegylated interferon-α2b (PegIFN) after 3 months (M3). The starting dose of PegIFN was 15 µg/week and it increased to 25 µg/week at M6 until M15. The combination was well tolerated with manageable toxicity. Of the patients, 84% remained on PegIFN at M12 and 91% (DAS) and 73% (PegIFN) of assigned dose was given. Only one patient had a pleural effusion during first year, and three more during the second year. After introduction of PegIFN we observed a steep increase in response rates. Major molecular response was achieved in 10%, 57%, 84% and 89% of patients at M3, M6, M12 and M18, respectively. At M12, MR(4) was achieved by 46% and MR(4.5) by 27% of patients. No patients progressed to advanced phase. In conclusion, the combination treatment appeared safe with very promising efficacy. A randomized comparison of DAS±PegIFN is warranted.

The Weil osteotomy: a seven-year follow-up.

We prospectively evaluated the one- and seven-year results of the Weil osteotomy for the treatment of metatarsalgia with subluxed or dislocated metatarsophalangeal joints in 25 feet of 24 patients. Good to excellent results were achieved in 21 feet (84%) after one year and in 22 (88%) after seven years. The American Orthopaedic Foot and Ankle Society score significantly improved from 48 (SD 15) points before surgery to 75 (SD 24) at one year, and 83 (SD 18) at seven years. The procedure significantly reduced pain, diminished isolated plantar callus formation and increased the patient's capacity for walking. Redislocation of the metatarsophalangeal joint was seen in two feet (8%) after one year and in three (12%) after seven years. Although floating toes and restricted movement of the metatarsophalangeal joint may occur, the Weil osteotomy is safe and effective.

Characterization of the pyruvate kinase-encoding gene (pki1) of Trichoderma reesei.

The pyruvate kinase-encoding gene (pki1) from Trichoderma reesei was isolated by hybridization to the corresponding Aspergillus nidulans pkiA gene. The 1614-bp nucleotide (nt) sequence of the cloned gene codes for a 538-amino-acid protein. The coding sequence contains a single intron of 246 nt at a position identical to that of intron E in the A. nidulans gene. The PKI protein shows extensive homology to the PKIs of A. nidulans and A. niger (67%) and Saccharomyces cerevisiae (59%). The 5' non-coding sequence contains a number of motifs typical for yeast glycolytic genes, but so far only rarely found in filamentous fungi.

The humane collection of fetal bovine serum and possibilities for serum-free cell and tissue culture.

Fetal bovine serum (FBS) is a common supplement to in vitro culture media. A workshop was organized to discuss whether or not fetuses might suffer when blood is withdrawn, and to discuss serum replacement methods. When bovine fetuses are exposed after slaughter of the dam, they can suffer only if they inflate their lungs with air and increase their blood oxygen to levels compatible with awareness. Preventing fetuses from breathing air or killing them by an efficient method, according to clearly defined safeguards, ensures that fetal blood collection is humane. Since serum is a supplement of unknown composition, which could be contaminated with unwanted factors, there are scientific and safety reasons for omitting FBS from culture media. Several media have been developed in which minimal or no animal derived components are present. Also, different cell types have been adapted to serum-free media. As yet, no standard serum free media are present, and each cell type requires its own medium composition. Among other recommendations, the establishment of a public database with information on cell types and their serum-free medium composition is proposed.

Skrljevo disease--two centuries of history.

Skrljevo disease, also called Rijeka (Fiume) or Grobnik disease, by some physicians was first identified in the village of Skrljevo in Croatia in 1790. From texts dating back to the beginning of the 19th century it is clear that it was a non-venereal (endemic) form of syphilis and represented a great calamity for the local people and a problem for the physicians. The disease was considered by some to be lepra, scurvy, scabies or others. The occurrence of the disease in the region around Rijeka was closely associated with the poor socioeconomic conditions present at that time in the region. It is interesting to note that many of the greatest physicians of the time such as Alibert, Frank, Hebra, Sigmund were acquainted with the disease and dealt with it in their writings. This paper gives a brief chronology of the major political events in the region since that time, underlying the measures used in fighting the disease.

Treatment of early syphilis with azithromycin.

An open, noncomparative study was performed to establish the efficacy of azithromycin in the treatment of early syphilis. Sixteen patients were treated with oral azithromycin: 1g the first day and then 500 mg for the following 8 days. Two patients were excluded from the study, leaving 14 patients for the evaluation of the efficacy. Venereal Disease Research Laboratory (VDRL) negativity was observed in 3 out of 6 patients treated for primary syphilis after 3 months and in all patients after 6 months. Two of 8 patients treated for manifest or early latent secondary syphilis had VDRL negativity after 3 months and 4 patients after 6 months. This study demonstrates that azithromycin is effective in the treatment of early syphilis. Two patients experienced gastrointestinal side effects which did not require treatment interruption.

Comparative trial of azithromycin and ciprofloxacin in the treatment of gonorrhea.

This single-blind (investigator) comparative study was designed to determine the efficacy and tolerability of 1 g of azithromycin vs 500 mg of ciprofloxacin both given as a single oral dose in patients with gonorrhea, who were constantly on the move. One hundred eight patients (59 men and 49 women) with clinically suspected gonococcal infection, confirmed by Gram-stain and culture, were enrolled. Data of 50 patients treated with azithromycin and 51 with ciprofloxacin were evaluable for efficacy and tolerability at the end of the study. After 2 weeks clinical and microbiological cure rates were 96.0% (48 out of 50) for the patients treated with azithromycin and 92.15% (47 out of 51) for the patients treated with ciprofloxacin (p > 0.05). Adverse reactions were reported in 5 patients treated with azithromycin and 6 with ciprofloxacin. In conclusion, 1 g azithromycin is at least as clinically and microbiologically effective and well tolerated as 500 mg of ciprofloxacin in the treatment of gonococcal infections. The drug is particularly useful for sailors and people constantly on the move.

Azithromycin compared with minocycline in the treatment of acne comedonica and papulo-pustulosa.

This open study was conducted in 72 outpatients with acne vulgaris, to compare the clinical efficacy and tolerability of azithromycin and minocycline. Azithromycin was administered as a single oral dose (500 mg/day) for 4 days in four cycles every 10 days and minocycline was administered 100 mg daily for 6 weeks. Improvement was assessed 6 weeks after initiation of treatment with a four-graded scale. A satisfactory clinical response was observed in 75.8% of the patients treated with azithromycin and in 70.5% of those treated with minocycline. There were no significant differences between these two acne treatments in terms of reduction of the number of lesions (p> 0.05). Both agents were well tolerated and mild side effects were reported in 10.3% of azithromycin and 11.7% of minocycline treated patients. We conclude that azithromycin is at least as clinically effective and well tolerated as minocycline as treatment of facial comedonic and papulopustular acne.

The Trichoderma cellulase regulatory puzzle: from the interior life of a secretory fungus.

Novel applications for cellulases have reinitiated interest in the regulation of production of these enzymes by the soft rot fungus Trichoderma reesei and related species. This paper reviews the current state of knowledge concerning the question "How can insoluble molecules like cellulose initiate their own breakdown by a microorganism?" The evidence available--based on biochemical as well as molecular biological approaches--favors a model in which conidial bound cellobiohydrolases carry out a first exo-exo-wise attack on the cellulose molecule. The disaccharides so formed (cellobiose, alpha-cellobiono-1,5-lactone) are then taken up by the mycelia and promote further cellulase biosynthesis. Evidence available suggests that they are further metabolized to, rather than being, the "true" inducer. Speculations on the nature of the inducer are presented. The roles of the beta-glucosidases of Trichoderma in this process are discussed. The pathway of cellulase secretion is discussed on the basis of electron microscopical as well as gene sequence information.

Influence of tumor thickness and vascularity on survival in cutaneous melanoma.

Eighty-eight cases of cutaneous melanoma (CM) were analyzed in order to elucidate the relationship between thickness, angiogenesis, and prognosis. The thickness of the tumor was measured according to the Breslow method, and the microvessels were identified by an immunohistochemical study using anti-factor VIII monoclonal antibody on specimens from 40 patients with superficial spreading melanoma (SSM), and 48 with nodular type (NM). Microvessels were counted in the area of highest density. The overall survival and disease-free period were analyzed retrospectively. The proportion of patients with thicker CMs (> 1.5 mm) increased with age in both sexes. Mean vascular count was statistically significant different only between thinner and thicker tumors in the SSM group (P < 0.05). Prognosis was correlated with the thickness of CM (P = 0.0002), mean vascular count alone (P = 0.004), mean vascular count in association with CM thickness less than 1.5 mm (P = 0.0005), and with mean vascular count in NM (P = 0.02). These findings suggest that increasing microvessel density indicates a worsening prognosis.

Family medicine training in Venezuela.

Family practice residency training in Venezuela is designed to prepare physicians to meet the health needs of the nation at a time of increasing societal concerns for the quality and cost of care. Since 1982, nine residency programs have been created throughout the country. Each two-year program is based in an ambulatory care setting. Entering physicians have completed an internship and have a minimum of two years practice experience. Graduates have been prepared to continue a socially active role to promote the new specialty. Training emphasizes community aspects of clinical practice, similar to the hopes of community-oriented primary care in the United States. Additional emphases include exposure to clinicians from other specialties, family aspects of patient care, working with a health care team, completion of a research project, and structured courses of theory in areas such as public health, behavioral medicine, and research methodology. Although hampered by economic constraints, the movement's intensely committed leaders have successfully captured political and public support.