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1.
Increasing evidence suggests that human epidermal melanocytes play an important role in the skin immune system; however, a role of their pigmentation in immune and inflammatory responses is poorly examined. In the study, the expression of Toll‐like receptor 4 (TLR4) and inflammatory cytokines and chemokines by cultured normal melanocytes derived from lightly and darkly pigmented skin was investigated after cell stimulation with lipopolysaccharide (LPS). The basal TLR4 mRNA level in heavily pigmented cells was higher as compared to their lightly pigmented counterparts. Melanocyte exposure to LPS upregulated the expression of TLR4 mRNA and enhanced the DNA‐binding activity of NF‐κB p50 and p65. We found substantial differences in the LPS‐stimulated expression of numerous genes encoding inflammatory cytokines and chemokines between the cells with various melanin contents. In lightly pigmented melanocytes, the most significantly upregulated genes were nicotinamide phosphoribosyltransferase (NAMPT/visfatin), the chemokines CCL2 and CCL20, and IL6, while the genes for CXCL12, IL‐16 and the chemokine receptor CCR4 were the most significantly upregulated in heavily pigmented cells. Moreover, the lightly pigmented melanocytes secreted much more NAMPT, CCL2 and IL‐6. The results of our study suggest modulatory effect of melanogenesis on the immune properties of normal epidermal melanocytes. 相似文献
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Efrat Rorman Chen Stein Zamir Irena Rilkis Hilla Ben-David 《Reproductive toxicology (Elmsford, N.Y.)》2006,21(4):458
Toxoplasma gondii (T. gondii) is the cause of toxoplasmosis. Primary infection in an immunocompetent person is usually asymptomatic. Serological surveys demonstrate that world-wide exposure to T. gondii is high (30% in US and 50–80% in Europe). Vertical transmission from a recently infected pregnant woman to her fetus may lead to congenital toxoplasmosis. The risk of such transmission increases as primary maternal infection occurs later in pregnancy. However, consequences for the fetus are more severe with transmission closer to conception. The timing of maternal primary infection is, therefore, critically linked to the clinical manifestations of the infection. Fetal infection may result in natural abortion. Often, no apparent symptoms are observed at birth and complications develop only later in life. The laboratory methods of assessing fetal risk of T. gondii infection are serology and direct tests.Screening programs for women at childbearing age or of the newborn, as well as education of the public regarding infection prevention, proved to be cost-effective and reduce the rate of infection.The impact of antiparasytic therapy on vertical transmission from mother to fetus is still controversial. However, specific therapy is recommended to be initiated as soon as infection is diagnosed. 相似文献
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The optical coherence tomography method was explored for two-dimensional flow mapping of a highly scattering fluid in flow with complex geometry. Converging flow (capillary entry) with 4:1 constriction was used for demonstration of non-invasive and remote methods of mapping varying velocity profiles. Downstream of the geometry was scanned with approximately 10 x 10 x 10 microm3 spatial resolution and structural imaging of the lumen and images of one particular velocity were acquired. Stable concave, blunted and parabolic profiles are obtained at different distances of the inlet length. Application of the technique for the blood circulation is also discussed. 相似文献
6.
CTLA-4 (CD152) gene polymorphism at position 49 in exon 1 in Graves' disease in a Polish population of the Lower Silesian region 总被引:2,自引:0,他引:2
Frydecka I Daroszewski J Suwalska K Zołedziowska M Tutak A Słowik M Potoczek S Dobosz T 《Archivum immunologiae et therapiae experimentalis》2004,52(5):369-374
INTRODUCTION: Graves' disease ((GD)is an autoimmune disease believed to be caused by a combination of environmental and genetic factors. The gene encoding cytotoxic T lymphocyte-associated antigen-4 (CTLA-4)is one of the candidate genes for conferring susceptibility to thyroid autoimmunity. he aim of the study was to investigate the association between the exon 1 CTLA-4 gene polymorphism A(49)G and susceptibility to GD and Graves ' ophthalmopathy (GO)as well as its severity in a Polish population of the Lower Silesia region. MATERIALS AND METHODS: We analyzed the A(49)G exon 1 CTLA-4 gene polymorphism in 99 unrelated Polish patients with GD, of whom 50 had clinically evident GO (NOSPECS class III and higher), and 154 matched healthy subjects from the Lower Silesia region. Genomic DNA was isolated from whole frozen blood using the NucleoSpin Blood kit. A/G transition was genotyped by polymerase chain reaction followed by labeling with the SnaPshot kit of PE Applied Biosystems and detected using an ABI PRISM 310 capillary genetic analyzer. RESULTS: The distribution of CTLA-4 exon 1 A(49)G enotype, allele, and phenotypic frequencies did not differ between patients with GD and healthy subjects. There was a significantly lower frequency of the AA genotype in the group of patients with clinically evident GO than in patients without severe GO (22% vs. 43%; p=0.02, OR=2.6). CONCLUSIONS: Our results showed that the AA genotype in patients with GD is associated with a lower risk of GO severity. 相似文献
7.
Ioana Maris Sabine Dölle-Bierke Jean-Marie Renaudin Lars Lange Alice Koehli Thomas Spindler Jonathan Hourihane Kathrin Scherer Katja Nemat C. Kemen Irena Neustädter Christian Vogelberg Thomas Reese Ismail Yildiz Zsolt Szepfalusi Hagen Ott Helen Straube Nikolaos G. Papadopoulos Susanne Hämmerling Ute Staden Michael Polz Tihomir Mustakov Ewa Cichocka-Jarosz Renata Cocco Alessandro Giovanni Fiocchi Montserrat Fernandez-Rivas Margitta Worm Network for Online Registration of Anaphylaxis 《Allergy》2021,76(5):1517-1527
Background
Peanut allergy has a rising prevalence in high-income countries, affecting 0.5%–1.4% of children. This study aimed to better understand peanut anaphylaxis in comparison to anaphylaxis to other food triggers in European children and adolescents.Methods
Data was sourced from the European Anaphylaxis Registry via an online questionnaire, after in-depth review of food-induced anaphylaxis cases in a tertiary paediatric allergy centre.Results
3514 cases of food anaphylaxis were reported between July 2007 - March 2018, 56% in patients younger than 18 years. Peanut anaphylaxis was recorded in 459 children and adolescents (85% of all peanut anaphylaxis cases). Previous reactions (42% vs. 38%; p = .001), asthma comorbidity (47% vs. 35%; p < .001), relevant cofactors (29% vs. 22%; p = .004) and biphasic reactions (10% vs. 4%; p = .001) were more commonly reported in peanut anaphylaxis. Most cases were labelled as severe anaphylaxis (Ring&Messmer grade III 65% vs. 56% and grade IV 1.1% vs. 0.9%; p = .001). Self-administration of intramuscular adrenaline was low (17% vs. 15%), professional adrenaline administration was higher in non-peanut food anaphylaxis (34% vs. 26%; p = .003). Hospitalization was higher for peanut anaphylaxis (67% vs. 54%; p = .004).Conclusions
The European Anaphylaxis Registry data confirmed peanut as one of the major causes of severe, potentially life-threatening allergic reactions in European children, with some characteristic features e.g., presence of asthma comorbidity and increased rate of biphasic reactions. Usage of intramuscular adrenaline as first-line treatment is low and needs to be improved. The Registry, designed as the largest database on anaphylaxis, allows continuous assessment of this condition.8.
9.
Roy Patterson Irena M. Suszko Stephen G. Hendrix C.Raymond Zeiss 《The Journal of allergy and clinical immunology》1981,67(2):162-165
Aqueous extracts of tree pollen were partially purified and polymerized with methods previously established for preparation of ragweed and grass polymers. The polymerized tree preparations were antigenic as demonstrated by ability to elicit immediate-type skin reactivity in humans and to induce an immune response in rabbits. The polymerized tree antigen was 100- to 10,000-fold less skin reactive than monomer tree antigen in tree pollen-sensitive patients but both preparations had similar antigenicity in rabbits. These results demonstrate that polymerized tree antigens can be prepared and should have the therapeutic potential already demonstrated for polymerized ragweed preparations. 相似文献
10.
The exact role and timing of reactivation of telomerase, a key enzyme implicated in cellular immortalization and transformation in the multistep process of laryngeal carcinogenesis, is still unknown. We attempted to (1) determine that quantitative differences exist in the levels of telomerase catalytic subunit (hTERT) mRNA expression among different grades of laryngeal epithelial abnormalities classified according to the Ljubljana classification; (2) determine that telomerase reactivation is an important, most probably early event in laryngeal carcinogenesis; and (3) analyze whether the relative quantity of hTERT mRNA can be used as a molecular biomarker in the early detection of precancerous lesions. The relative quantity of hTERT mRNA, expressed as an hTERT index, was analyzed in 140 frozen laryngeal tissue specimens representing different morphological stages of laryngeal carcinogenesis by using a commercially available LightCycler Telo TAGGG hTERT Quantification kit. The presence and relative quantity of hTERT mRNA in laryngeal epithelium increases progressively with the degree of epithelial abnormalities. hTERT mRNA was detectable in 1/15 normal laryngeal epithelia (7%, mean hTERT index 0.02), 3/15 simple hyperplasias (20%, mean hTERT index 0.09), 10/27 abnormal hyperplasias (37%, mean hTERT index 0.18), 9/12 atypical hyperplasias (75%, mean hTERT index 0.74), 8/9 intraepithelial carcinomas (89%, mean hTERT index 1.82), and 53/62 invasive laryngeal squamous cell carcinomas (85%, mean hTERT index 2.51). Statistical analysis revealed two groups of laryngeal epithelial changes with significant differences in the levels of hTERT mRNA expression (P <.0033): (1) normal and reactive hyperplastic laryngeal epithelium (simple and abnormal hyperplasia) and (2) atypical hyperplasia (precancerous lesion), intraepithelial and invasive laryngeal squamous cell carcinoma. The results of the present study suggest that telomerase reactivation is an early event in laryngeal carcinogenesis, detectable already at the stage of precancerous laryngeal epithelial changes. Nevertheless, other genetic abnormalities appear to be necessary for progression of these epithelial abnormalities toward invasive laryngeal squamous cell carcinoma. 相似文献