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21.
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
22.
Jae Eun Choi Tyler Werbel Zhenping Wang Chia Chi Wu Tony L. Yaksh Anna Di Nardo 《Journal of dermatological science》2019,93(1):58-64
Background
Rosacea is a chronic inflammatory skin condition whose etiology has been linked to mast cells and the antimicrobial peptide cathelicidin LL-37. Individuals with refractory disease have demonstrated clinical benefit with periodic injections of onabotulinum toxin, but the mechanism of action is unknown.Objectives
To investigate the molecular mechanism by which botulinum toxin improves rosacea lesions.Methods
Primary human and murine mast cells were pretreated with onabotulinum toxin A or B or control. Mast cell degranulation was evaluated by β-hexosaminidase activity. Expression of botulinum toxin receptor Sv2 was measured by qPCR. The presence of SNAP-25 and VAMP2 was established by immunofluorescence. In vivo rosacea model was established by intradermally injecting LL-37 with or without onabotulinum toxin A pretreatment. Mast cell degranulation was assessed in vivo by histologic counts. Rosacea biomarkers were analyzed by qPCR of mouse skin sections.Results
Onabotulinum toxin A and B inhibited compound 48/80-induced degranulation of both human and murine mast cells. Expression of Sv2 was established in mouse mast cells. Onabotulinum toxin A and B increased cleaved SNAP-25 and decreased VAMP2 staining in mast cells respectively. In mice, injection of onabotulinum toxin A significantly reduced LL-37-induced skin erythema, mast cell degranulation, and mRNA expression of rosacea biomarkers.Conclusions
These findings suggest that onabotulinum toxin reduces rosacea-associated skin inflammation by directly inhibiting mast cell degranulation. Periodic applications of onabotulinum toxin may be an effective therapy for refractory rosacea and deserves further study. 相似文献23.
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25.
Anna Grace Tribble Phillip Summers Haiying Chen Sara A. Quandt 《Archives of environmental & occupational health》2016,71(6):309-316
The jobs of Latino manual laborers place their mental and physical health at risk. This study evaluates the associations among musculoskeletal pain, mental health, and work organization in Latino manual laborers. Farmworkers and nonfarmworkers (n = 189) in North Carolina were interviewed for self-reported musculoskeletal pain, depressive symptoms, stress, work safety climate, and precarious job status. More nonfarmworkers than farmworkers had neck and shoulder pain, but they did not differ in other areas of musculoskeletal pain. Depressive symptoms had a significant association with neck and shoulder pain (p < .05). Precariousness had a significant association with back pain (p < .05). Farmworker participants had H-2A visas and were afforded some protection compared to nonfarmworker manual workers. Research is needed to improve policy that relieves pain and improves mental health for all Latino manual workers. 相似文献
26.
Flavia Temperilli Aldona Rina Isabella Massimi Anna Lisa Montemari Maria Luisa Guarino Alessandra Zicari 《Platelets》2015,26(8):783-787
Serum thromboxane-B2 (TxB2), together with arachidonic acid (AA)-induced platelet aggregation, are, at the moment, the most used tests to identify patients displaying high on-aspirin treatment platelet reactivity (HAPR). Both tests are specific for aspirin action on cyclooxygenase-1. While the correlation between serum TxB2 assay and clinical outcome is established, data are conflicting with regard to aspirin treatment and a possible association with AA-stimulated platelet markers and clinical outcome. To understand such discrepancy, we performed a retrospective study to compare both assays. We collected data from 132 patients receiving a daily dose of aspirin (100?mg/day) and data from 48 patients receiving aspirin on alternate days. All Patients who received a daily dose of aspirin were studied for AA-induced platelet aggregation together with serum TxB2 levels and AA-induced TxB2 formation was also studied in 71 patients out of entire population. Consistent with recommendations in the literature, we defined HAPR by setting a cut-off point at 3.1?ng/ml for serum levels of thromboxane B2 and 20% for AA-induced platelet aggregation. According to this cut-off point, we divided our overall population into two groups: (1) TxB2?<?3.1?ng/ml and (2) TxB2?>?3.1?ng/ml. We found low agreement between such tests to identify patients displaying HAPR. Our results show that AA-induced platelet aggregation >20% identify a smaller number of HAPR patients in comparison with TxB2. A good correlation between serum TxB2 and arachidonic acid-induced TxB2 production was found (r?=?0.76619). 相似文献
27.
Inflammation but not obesity or insulin resistance is associated with increased plasma fibroblast growth factor 23 concentration in the elderly 下载免费PDF全文
28.
目的 观察“调任通督法”针刺治疗围绝经期潮热的临床疗效和安全性。方法 将符合纳入标准的72例围绝经期潮热患者,按照1∶1的比例随机分为治疗组(针刺组)和对照组(等待组)。治疗组取穴百会、印堂、神庭、关元、气海、中脘、阴郄、太溪、复溜、三阴交。针刺治疗每次持续30 min,每周2次,连续治疗6周。对照组为等待组,试验期间仅给予同针刺组相同的健康宣教,两组分别于治疗前、治疗第3周、治疗第6周以及第10周随访评估其潮热频率和程度,以及更年期生活质量量表(Menopause-specific quality of life questionnaire,Men-QoL)的变化情况,同时记录针刺不良事件的发生。结果 ①潮热频率及潮热程度:在治疗后及随访时,针刺组较等待组有明显改善,差异具有统计学意义(P < 0.01)。与治疗前相比,针刺组第3周即出现了潮热频率明显下降的趋势(P < 0.01),治疗后以及随访期针刺组潮热频率及潮热程度均较治疗前有明显统计学差异(P < 0.01)。而等待组在各时间点潮热频率及潮热程度均无统计学差异(均P > 0.05)。②围绝经期生活质量量表:治疗后针刺组在Men-QoL总分、血管舒缩功能评分、社会心理、体能状况较等待组比较均有统计学差异(均P < 0.01)。在随访期,针刺组在Men-QoL社会心理以及体能方面明显改善,差异均具有统计学意义(P < 0.01,P < 0.05)。两组Men-QoL性功能在治疗后及随访期均无统计学差异(P > 0.05)。与治疗前相比,在治疗后及随访期,针刺组Men-QoL总分、血管舒缩功能、社会心理、体能状况均有统计学差异(均P < 0.05),在Men-QoL性功能方面无统计学差异(P > 0.05)。等待组在Men-QoL总分及四个域方面均无明显改善,无统计学意义(均P > 0.05)。结论 调任通督法针刺治疗围绝经期潮热安全有效,且对围绝经期生活质量有所改善。 相似文献
29.
Emarene Kalaw Malcolm Lim Jamie R. Kutasovic Anna Sokolova Lucinda Taege Kate Johnstone James Bennett Jodi M. Saunus Colleen Niland Kaltin Ferguson Irma Gresshoff Mark Bettington Nirmala Pathmanathan Gary M. Tse David Papadimos Rajadurai Pathmanathan Gavin Harris Rin Yamaguchi Puay Hoon Tan Stephen Fox Sandra A. O’Toole Peter T. Simpson Sunil R. Lakhani Amy E. McCart Reed 《British journal of cancer》2020,123(11):1665
30.