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    Cryptosporidium species and Cryptosporidium parvum subtypes in dairy calves and goat kids reared under traditional farming systems in Turkey
    (Academic Press Inc Elsevier Science, 2016) Taylan-Ozkan, Aysegul; Yasa-Duru, Sibel; Usluca, Selma; Lysen, Colleen; Ye, Jianbin; Roellig, Dawn M.; Xiao, Lihua
    Molecular characterizations of Cryptosporidium spp. in ruminants reared under traditional animal management systems are scarce and studies conducted thus far have revealed largely an absence of the pathogenic and zoonotic species Cryptosporidium parvum in pre-weaned animals. In this study, we examined Cryptosporidium species and subtype distribution in free-range pre-weaned dairy calves and goat kids with diarrhea. Cryptosporidium-positive specimens from pre-weaned calves on 10 farms and goat kids on 4 farms in Ankara, Balikesir, Corum, Kirikkale, and Kirsehir Provinces, Turkey were genotyped by PCR-restriction length polymorphism analysis of the small subunit rRNA gene, which identified C. parvum in 27 calves and 9 goat kids and Cryptosporidium ryanae in 1 calf. Among the C. parvum isolates successfully subtyped by DNA sequence analysis of the 60 kDa glycoprotein gene, three subtypes were detected in calves, including IlaA13G2R1 (20/23), IldA18G1 (2/23), and IldA20G1b (1/23), and four subtypes were detected in goat kids, including IlaA13G2R1 (3/8), IlaA15G1R1 (2/8), IldA22G1 (2/8), and IldA18G1 (1/8). Data of the study suggest that dairy calves reared in a traditional cow-calf system in Turkey are mainly infected with a C. parvum subtype rarely seen elsewhere, whereas goat kids are infected with diverse subtypes. As all five C. parvum subtypes found in this study are known human pathogens, pre-weaned farm animals could play a potential role in the transmission of human cryptosporidiosis. (C) 2016 Elsevier Inc. All rights reserved.
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    Skin-homing T-cell responses associated with Demodex infestation and rosacea
    (Wiley, 2019) Gazi, Umut; Gureser, Ayse Semra; Oztekin, Aynure; Karasartova, Djursun; Kosar-Acar, Nezahat; Derici, Mehmet Kursat; Taylan-Ozkan, Aysegul
    Aims Our aim was to investigate the skin-homing T-cell immune responses triggered in patients with Demodex infestation and/or rosacea. Methods Collected whole blood samples were divided into four groups: control subjects; nonrosacea patients with Demodex infestation (Demodex group); papulopustular rosacea (PPR) patients without Demodex infestation (Rosacea group); and PPR patients with Demodex infestation (Rosacea/Demodex group). Following ex vivo activation, skin-homing CLA+CD4+ T-cell subset levels were monitored by flow cytometry. Results When compared with control subjects, among skin-homing CD4+ T-cell subsets analysed, Demodex patients had higher T(H)9 and T-reg cell levels; Rosacea subjects displayed elevated T(H)1 cell levels; and Rosacea/Demodex patients exhibited increased frequencies of T(H)9 and T(H)22 cells. In contrast to Rosacea subjects, Rosacea/Demodex group members displayed higher T(H)2 cell levels; and when compared with Demodex groups, they had higher T(H)1 and T(H)2 but lower T-reg cell levels. Demodex group members also exhibited higher T-reg but lower T(H)1 and T(H)22 levels than Rosacea/Demodex group subjects. Conclusions The skin-homing T-cell responses associated with Demodex infestation and rosacea formation seem to influence each other. The present as well as future studies could contribute to the development of effective treatment strategies for demodicosis and rosacea.
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    Usnic acid causes apoptotic-like death in Leishmania major, L. infantum and L. tropica
    (Springer Heidelberg, 2018) Derici, Mehmet Kursat; Cansaran-Duman, Demet; Taylan-Ozkan, Aysegul
    Leishmaniasis, a deadly parasitic infection, threatens many people worldwide. Since the high cost, toxicity, and resistance are drawbacks of current treatment options, it is necessary to find safer and more effective new antileishmanial drugs. The aim of this study was to determine the antileishmanial activity of usnic acid and its apoptotic mechanism on Leishmania spp. promastigotes. The antileishmanial activity was evaluated by MTT assay and apoptosis-related gene expression was investigated by qRT-PCR. Usnic acid was to be effective against Leishmania major, L. infantum, and L. tropica promastigotes at IC50 =10.76 mu g/ml, 13.34 mu g/ml, and 21.06 mu g/ml, respectively. We also demonstrated a novel mechanism by which usnic acid inhibited proliferation and caused apoptosis; usnic acid upregulated p53, Bax, Casp-3, and Casp-9 gene expression and downregulated the level of Bcl-2 gene expression. Accordingly, the expression level of the P53 gene increased in L. major, L. infantum and L. tropica by 14.4-, 11.8-, and 9.5-fold, respectively, and in contrast, the Bcl-2 gene expression decreased in all three leishmaniasis by 0.8-, 0.8-, and 0.7-fold, respectively. The present study, therefore, revealed that usnic acid played a critical role in the usnic acid-induced apoptotic process in Leishmania species. Usnic acid is easily accessible and an inexpensive agent, and can be considered as an alternative therapeutic agent for Leishmania infections subject to further tests in animal models.