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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Retrospektive Analyse von Wirksamkeit, Sicherheit, prognostischen Parametern und Faktoren der Lebensqualität bei der topischen Immuntherapie der Alopecia areata mit Diphenylcyclopropenon / Retrospective analysis of efficacy, safety, prognostic parameters and factors regarding quality of life of the topic immunotherapy of alopecia areata with diphenylcyclopropenone

Rasche, Florian January 2021 (has links) (PDF)
Diese retrospektive Analyse untersucht die Behandlung von Patienten mit Alopecia areata in der Klinik und Poliklinik für Dermatologie, Venerologie und Allergologie der Universitätsklinik Würzburg mit Diphenylcyclopropenon und beleuchtet Faktoren der durch die Behandlung beeinflussten Lebensqualität. / This study evaluates the efficacy of the treatment of alopecia areata in the dermatology department of the university clinic in Würzburg, Germany and shows prognostic factors that may be detrimental in regards to a positive outcome. Furthermore, the influence of the therapy's side-effects on everyday life are shown.
2

A "hair-raising" history of alopecia areata

Broadley, David, McElwee, Kevin J. 20 January 2020 (has links)
Yes / A 3500‐year‐old papyrus from ancient Egypt provides a list of treatments for many diseases including “bite hair loss,” most likely alopecia areata (AA). The treatment of AA remained largely unchanged for over 1500 years. In 30 CE, Celsus described AA presenting as scalp alopecia in spots or the “windings of a snake” and suggested treatment with caustic compounds and scarification. The first “modern” description of AA came in 1813, though treatment still largely employed caustic agents. From the mid‐19th century onwards, various hypotheses of AA development were put forward including infectious microbes (1843), nerve defects (1858), physical trauma and psychological stress (1881), focal inflammation (1891), diseased teeth (1902), toxins (1912) and endocrine disorders (1913). The 1950s brought new treatment developments with the first use of corticosteroid compounds (1952), and the first suggestion that AA was an autoimmune disease (1958). Research progressively shifted towards identifying hair follicle‐specific autoantibodies (1995). The potential role of lymphocytes in AA was made implicit with immunohistological studies (1980s). However, studies confirming their functional role were not published until the development of rodent models (1990s). Genetic studies, particularly genome‐wide association studies, have now come to the forefront and open up a new era of AA investigation (2000s). Today, AA research is actively focused on genetics, the microbiome, dietary modulators, the role of atopy, immune cell types in AA pathogenesis, primary antigenic targets, mechanisms by which immune cells influence hair growth, and of course the development of new treatments based on these discoveries. / Alopecia UK.
3

Sequential cyclic changes of hair roots revealed by dermoscopy demonstrate a progressive mechanism of diffuse alopecia areata over time.

Zhang, X., Ye, Y., Zhu, Z., Yang, Y., Cao, H., McElwee, Kevin J., Ling, Y. 12 March 2019 (has links)
Yes / BACKGROUND: Diffuse alopecia areata (DAA) often leads to a complete hair shedding within a few months. OBJECTIVE: To explore features and mechanisms underlying DAA. MATERIALS AND METHODS: Scalp and hair root dermoscopy were conducted on 23 DAA patients throughout the disease process, 20 patchy Alopecia areata patients, 23 acute telogen effluvium (ATE) patients and 10 normal controls. Histopathology was also evaluated. RESULTS: We found almost all hair roots were anagen in early stage DAA in 18 patients (18/23, 78.3%) within the first 4-8 weeks after hair loss onset. Anagen effluvium (~4 weeks) was followed by catagen (~4 weeks) and then telogen/exogen (~8 weeks) effluvium with overlap. Hair root and proximal hair shaft depigmentation was more prominent in later DAA disease stages. Black dots, exclamation mark hairs and inconsistent thickness of hair shafts were found more often in early than later DAA (Ps < 0.01). Early DAA histopathology revealed more prominent inflammation and hair follicle regression than that observed in the later stages. Patchy alopecia areata patients showed mixed anagen, catagen and telogen hair roots while ATE patients showed increased exogen and mildly decreased hair root pigmentation. CONCLUSION: Sequential cyclic staging of shed hairs in DAA indicates the insult may be hair-cycle specific. We suggest that DAA is initially an anagen effluvium disease involving an intense inflammatory insult, later progressing to a brief catagen effluvium, and then to telogen effluvium with premature exogen, in later stages of DAA. / This study was supported by the following grants to Xingqi Zhang: National Natural Science Foundation of China (81573066); Natural Science Foundation of Guangdong Province (2014A030313098).
4

Die Expression von Chemokinen bei entzündlichen Reaktionen der Haut / The expression of chemokines in inflammatory skin diseases

Toksoy, Atiye January 2008 (has links) (PDF)
Für das Verständnis der Pathogenese entzündlicher Hauterkrankungen ist die Zusammensetzung des zellulären Entzündungsinfiltrates und die Verteilung der Entzündungszellen von wesentlicher Bedeutung. In Anbetracht der chemotaktischen Funktion der Chemokine liegt die Annahme nahe, dass das zelluläre Infiltrationsmuster in entzündlichen Hauterkrankungen das Expressionsmuster von Chemokinen und umgekehrt widerspiegelt. Die Infiltrationsroute der Leukozyten in die Haut erfolgt immer vom Lumen dermaler Gefäße in das dermale Milieu und ggf. weiter in das epidermale Kompartiment (sog. Epidermotropismus). Die Migration inflammatorischer Zellen über die Grenzen unterschiedlicher Hautkompartimente hinweg ist einzigartig und präsentiert ein ideales Modell, um die chemotaktischen Cytokin- bzw. Chemokinfunktionen zu evaluieren. Anhand verschiedener ausgewählter Hautdermatosen (Wundheilung, Psoriasis, Alopecia areata) wurden die unterschiedlichen Expressionsmuster einer Auswahl von Chemokinen untersucht. Dabei nehmen Chemokine, die von Endothelzellen exprimiert bzw. sezerniert werden, eine zentrale Rolle ein, da sie eine „Pförtnerfunktion“ ausführen. Diese Funktion ist entscheidend bei der Rekrutierung und Akkumulation der für das Erkrankungsbild und bei reparativen Vorgängen der Wundheilung spezifischen Leukozytensubpopulation ins dermale bzw. epidermale Gewebe / The composition of the cellular inflammatory infiltrates and the distribution of inflammatory cells is essential for the understanding of the pathogenesis of inflammatory skin diseases. In view of the chemotactic function of chemokines we assume that the cellular infiltration pattern in inflammatory skin diseases reflects the expression patterns of chemokines and vice versa. The route of leukocyte infiltration into the skin is always directed from the lumen of dermal vessels in the dermal milieu and in some cases further into the epidermal compartment (so-called epidermotropism). The migration of inflammatory cells across the borders of different skin compartments is unique and represents an ideal model to evaluate the chemotactic function of cytokines or chemokines. In various representative dermatoses (wound healing, psoriasis, alopecia areata) we investigated the different expression patterns of selected chemokines. Chemokines, expressed or secreted by endothelial cells, play an important role because they exert a "gatekeeper function". This is crucial in the recruitment and accumulation pattern of the disease and repair processes of wound-specific leukocyte subpopulation, which invade the dermal and epidermal compartment.
5

Kortikosteroider som behandling mot Alopecia Areata

Wendel, Caroline January 2008 (has links)
<p>Alopecia areata (AA) betyder fläckvis håravfall och uppstår vanligen på huvudet men även på kroppen. Det är en harmlös, reversibel, organ-specifik, autoimmun hudsjukdom som drabbar hårfolliklarna. Den autoimmuna reaktionen förmedlas av T-lymfocyter som angriper hårfolliklarna och hämmar hårväxt. Det årliga incidenstalet för både kvinnor och män är 20,2 per 100 000 personer och 1,7 % av befolkningen riskerar att drabbas någon gång under livet. Även om genetiskt anlag och miljöfaktorer, såsom emotionell stress, graviditet och tillfälliga infektioner kan utlösa sjukdomen så är den exakta orsaken fortfarande okänd. De behandlingar som finns mot AA påverkar inte den autoimmuna processen som orsakar alopecin utan syftet med dessa är att stimulera hårfolliklarna och dämpa sjukdomens aktivitet. Kortikosteroider används vid behandling mot AA, men kan ge svåra biverkningar vid långvarig behandling. De olika administrationsformer av kortikosteroider som används mot AA är främst lokala och systemiska, men även intralesionella.</p><p>Målet med denna litteraturstudie var att undersöka om kortikosteroider har någon effekt mot AA. Samtliga studier visade att kortikosteroider har effekt mot AA, men att risken för återfall är stor. Tre av de fem studierna visade att behandlingen gav bättre resultat hos de patienterna med mindre svår AA, kort duration och första episoden av sjukdomen. Dåliga prognostiska faktorer visade sig vara omfattande AA, lång duration, atopi, nagelinvolvering och flera episoder av sjukdomen.</p><p>En studie visade att patienter med plurifocal AA svarar bättre på behandlingen än patienter med ophiasic AA, AA totalis och AA universalis. I samtliga studier fick patienterna biverkningar av behandlingen med dessa var inte så allvarliga att patienterna fick avbryta behandlingen. Slutsatsen av detta arbete är att kortikosteroider har effekt mot AA, men att risken för återfall är stor.</p><p>2008:F3</p>
6

Genetic and Environmental Determinants of Alopecia Areata

January 2020 (has links)
Alopecia Areata (AA) is a highly prevalent autoimmune disease in the US with a lifetime risk of 2.1%. In AA, autoimmunity develops against the hair follicles, which leads to infiltration of immune cells around affected follicles. Among genetic risk factors in complex autoimmune diseases, variants cluster in genes regulating the immune response, as well as the target organ. AA is believed to result from both genetic and environmental factors. To identify underlying genetic drivers in AA, we analyzed AA risk genes using various sequencing techniques and analysis methods to identify causal variants and placed them in functionally relevant contexts using innovative mapping techniques. To address the role of variants in immune function, we studied the Interleukin-2 Receptor Alpha (IL2RA), which we identified as a significant locus to study genetic factors underlying immune function from our AA GWAS studies (p=1.74*10-12)11. IL2RA plays a crucial role in regulating immune tolerance and controlling activity of regulatory T cells (Treg)13. We identified significant causal variants in the IL2RA region associated with AA using GWAS, targeted resequencing, and custom capture exome sequencing approaches. We validated the expression of these variants in immune cell cluster tissue types in silico, and specifically in CD4+ T cells. The variant rs3118740 increases AA susceptibility for carriers of the C allele. Such allele specific effects could lead to a perturbation of Treg function, for example, one study in T1D where patients with the rs3118470 risk variant have Treg with IL-2 signaling defects14. These studies demonstrated that identifying causal variants may lead to an improved understating of Treg function and risk of autoimmunity in AA. Next, to study genetic susceptibility in the target organ in AA, the hair follicle (HF), the second candidate GWAS susceptibility gene we studied was peroxiredoxin 5 (PRDX5) (p= of 8.7*10-14), which is also a GWAS gene in Crohn’s disease, sarcoidosis, and psoriasis15,16. PRDX5 is a member of the family of antioxidant enzymes that are crucial for regulating oxidative stress. Our lab performed whole exome sequencing in 849 AA patients, together with selected custom capture regions of genomic sequencing. Using a test of variant enrichment, we identified variants in PRDX5 that were significant in both our GWAS and exome studies, and thus represented likely candidate causal variants. Using Bayesian fine mapping, we identified a GWAS and exome sequencing variant, rs574087, that was significantly enriched in both, and is predicted to be a causal variant in keratinocytes and melanocytes. To functionally validate PRDX5, we immunostained healthy human HF and AA affected HF, and found that PRDX5 is upregulated AA human HF. PRDX5 is expressed in cultured melanocytes by immunostaining, which is consistent with melanocytes exhibiting high levels of oxidative stress. We postulated that PRDX5 may be involved in protection from oxidative stress, and that its dysregulation may contribute to autoimmunity. Finally, along with genetic predisposition, environmental triggers such as the microbiome have emerged as potential factors contributing to pathologic immune responses in autoimmune diseases. To determine the role of the microbiome in AA pathobiology, we performed 16S rRNA sequencing of skin swabs, hair follicles, and stool samples from a cohort of 34 AA patients and 12 healthy controls (HCs). Unexpectedly, we found evidence of striking gut dysbiosis, consisting of over-representation of Firmicutes and under-representation of Bacteroides in the gut microbiome of AA patients compared with healthy subjects, but no significant differences in skin or hair follicle (HF) microbiome composition. To investigate the role of the gut microbiome in AA development in vivo, we depleted the gut microbiome in C3H/HeJ mice and found that the mice were largely protected from AA developing. These data revealed a requirement for gut microbiota in the onset of murine AA. Taken together with recent reports in the literature of reversal of AA in several patients following fecal microbiota transplant (FMT)17,18, our findings suggest that restoring homeostasis of the gut microbiome may represent an effective new treatment modality in the management of AA.
7

Alopecia areata and vitiligo - partners in crime or a case of false alibis

Tobin, Desmond J. January 2014 (has links)
No / It has long been appreciated in science that correlation does not imply causation. However, with any logical fallacy, simply spotting that the reasoning behind an argument is faulty does not imply that the resulting conclusion is false. Thus, I begin the tricky business of exploring the basis upon which researchers and clinicians are often tempted to conclude that two medical conditions (here alopecia areata and vitiligo), with some striking resemblances, are in fact related. This is relevant, particularly if assumptions of shared aetiology (and to some extent shared pathomechanism) encourage a common strategy to finding a treatment or cure.
8

Serum level of IL-4 predicts response to topical immunotherapy with diphenylcyclopropenone in alopecia areata.

Gong, Y., Zhao, Y., Zhang, X., Qi, S., Li, S., Ye, Y., Yang, J., Caulloo, S., McElwee, Kevin J., Zhang, X. 12 March 2019 (has links)
Yes / Background: This study investigated predictors of response to topical diphenylyclopropenone (DPCP) immunotherapy in patients with alopecia areata (AA). Objective: To identify predictors of response, or resistance, to treatment for AA through clinical observations and serum tests. Methods: Eighty four AA patients were treated with DPCP. Serum cytokine levels were measured in 33 AA patients pre- and post-treatment, and in 18 healthy controls, using ELISA assays. Results: Of patients, 56.1% responded to DPCP with satisfactory hair regrowth; the response rate was negatively correlated with hair loss extent. Before DPCP treatment, higher serum IFN-γ and IL-12 cytokine levels were observed in AA patients compared to healthy controls. Non-responders to DPCP had significantly elevated serum IL-4 pre-treatment (3.07 fold higher) and lower IL-12 levels compared with responders. After DPCP treatment, non-responders had persistently high IL-4, increased IL-12, negligible decrease in IFN-γ and decreased IL-10. Post-treatment DPCP responders exhibited significantly decreased IFN-γ and IL-12, and increased IL-4 and IL-10. Development of adverse side-effects was significantly associated with higher pre-treatment serum IgE levels. Limitations: A small number of subjects were evaluated. Conclusions: Potentially, elevated pre-treatment serum levels of IL-4 and IL-12 can be used as unfavorable and favorable predictors of DPCP therapeutic effect, respectively. In addition, pre-treatment elevated serum total IgE may predict increased risk for severe adverse side-effects to DPCP application. Whether serum cytokine expression levels can be used as predictors of response to other forms of treatment is unknown, but it may warrant investigation in the development of personalized treatments for AA. / This work is supported by the National Natural Science Foundation of China (81573066) and Natural Science Foundation of Guangdong Province (2014A030313098) to Xingqi Zhang.
9

Increased expression of TLR7 and TLR9 in alopecia areata

Kang, H., Wu, W-Y., Yu, M., Shapiro, J., McElwee, Kevin J. 10 December 2019 (has links)
Yes / Alopecia areata (AA) is thought to be an autoimmune process. In other autoimmune diseases, the innate immune system and Toll‐like receptors (TLRs) can play a significant role. Expression of TLR7, TLR9 and associated inducible genes was evaluated by quantitative PCR in peripheral blood mononuclear cells (PBMCs) from 10 healthy individuals and 19 AA patients, categorized according to disease duration, activity and hair loss extent. Microdissected scalp biopsies from five patients and four controls were also assessed by quantitative PCR and immunohistology. TLR9 was significantly upregulated 2.37 fold in AA PBMCs. Notably, TLR9 was most significantly upregulated in patients with active AA, as shown by a positive hair pull test, compared to stable AA patients. In hair follicle bulbs from AA patients, IFNG and TLR7 exhibited statistically significant 3.85 and 2.70 fold increases in mRNA, respectively. Immunohistology revealed TLR7 present in lesional follicles, while TLR9 positive cells were primarily observed peri‐bulbar to AA affected hair follicles. The increased expression of TLR7 and TLR9 suggest components of the innate immune system may be active in AA pathogenesis. / National Alopecia Areata Foundation; Canadian Dermatology Foundation; Michael Smith Foundation for Health Research, Grant/Award Number: CI‐SCH‐00480(06‐1); Canadian Institutes of Health Research, Grant/Award Number: MOP‐167368 and MSH‐192593‐140450
10

Allergy promotes alopecia areata in a subset of patients

Zhang, X., McElwee, Kevin J. 10 December 2019 (has links)
Yes / In this commentary, we focus on allergy as a facilitating factor in the pathogenesis of alopecia areata (AA). From previous studies on AA, it is well known that subsets of patients can have one or more of; seasonal relapse, comorbid atopic rhinitis, asthma and dermatitis, lesion infiltrating eosinophils and plasma cells, high levels of total IgE, specific IgE for house dust mites (HDMs), and/or disrupted skin barrier function by the evaluation of filaggrin. Allergy and AA share a similar genetic background; both contributing to an immune reaction imbalance. Furthermore, adjunctive treatment with antihistamines, or desensitization for HDM, can reduce the severity of alopecia in atopic AA patients. Therefore, allergies may contribute to the onset and relapse of AA. Identification of an allergic or atopic immune component in AA patient subsets may indicate adjunctive treatment intervention measures against allergies should be taken which may improve the success of conventional AA treatment.

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