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    Influence of some knitting and finishing parameters on the snag resistance of polyethylene terephthalate (PET) knit fabric
    (Sage Publications Ltd, 2022) Yibar, Mehmet Fahri; Ogut, Hamdi; Cingu, Neslihan; Cetin, Suna; Yatikci, Tugce Koroglu; Yildirim, Kenan
    To assess the effects of fabric take-up, yarn tension, feeder position, and yarn feeder material on the occurrence of snagging, fabrics produced with two different finishing processes, were subjected to longitudinal or transversal 100, 300, and 600 revolutions, and the degree of snagging was measured and compared afterwards with gray fabric. Our results showed that, during the knitting process, the use of ceramic yarn feeders resulted in significantly fewer snags compared with metal yarn feeders. The gray fabric, having no finishing, was fragile and easily snagged, whereas the fabric treated by a finishing process - either drying in relaxed condition (Treatment A) or under stress conditions (Treatment B) - was more resistant to snagging. Moreover, the snagging property of the gray fabric tended to increase with increasing longitudinal or transversal 100, 300, or 600 revolutions. Slight increases in snagging were also present in fabrics having Treatment A or Treatment B at the same revolutions, but the differences were not statistically important (P > 0.05). Frequency of snags was higher when revolutions were transversal rather than on longitudinal direction. Yarn tension and feeder position had no effect on snagging degree, while fabric take-up had limited effect. For acquiring a fabric resistant to snagging, the gray fabric produced with ceramic yarn guiders during the knitting process should be subjected to drying under relaxed condition. We also suggest that quality control tests be carried out taking the results of our study into consideration.
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    The Ocular Endothelin System: A Novel Target for the Treatment of Endotoxin-Induced Uveitis With Bosentan
    (Assoc Research Vision Ophthalmology Inc, 2014) Keles, Sadullah; Halici, Zekai; Atmaca, Hasan Tarik; Yayla, Muhammed; Yildirim, Kenan; Ekinci, Metin; Bayraktutan, Zafer
    PURPOSE. We compared the anti-inflammatory effects of bosentan and dexamethasone in endotoxin-induced uveitis (EIU). METHODS. Endotoxin-induced uveitis was induced by subcutaneous injection of lipopolysaccharide (LPS, 200 mu g) in Wistar rats. Rats were divided randomly into 10 groups (n=6). Bosentan at doses of 50 and 100 mg/kg were administered orally 1 hour before and 12 hours after LPS injection, and dexamethasone was administered by intraperitoneally 30 minutes before and 30 minutes after LPS injection at a dose of 1 mg/kg. Data were collected at two time points for each control and treatment; animals were killed at either 3 or 24 hours after LPS injection. Histopathologic evaluation and aqueous humour measurements of TNF-alpha level were performed, and endothelin-1 (ET-1), inducible nitric oxide synthase (iNOS), and endothelin receptor A and B (EDNRA and B) expression were analyzed. RESULTS. The group treated with 100 mg/kg bosentan at 24 hours displayed significantly milder uveitis and fewer inflammatory cells compared to LPS-injected animals, and there were similar findings in the dexamethasone-treated group at 24 hours. The TNF-alpha levels in the dexamethasone treatment group were lower than those in the LPS-induced uveitis control group (P < 0.05); however, there was no difference between the dexamethasone and bosentan treatment groups at 3 and 24 hours after LPS administration. Bosentan treatment at doses of 50 and 100 mg/kg significantly decreased iNOS expression compared to LPS-injected animals (P < 0.001). The ET-1 expression was suppressed significantly by bosentan and dexamethasone at 3 and 24 hours after LPS administration (P < 0.001). The EDNRA expression in the bosentan treatment groups was statistically significantly lower than that in the LPS-induced uveitis control group at 3 and 24 hours after LPS administration (P < 0.05). CONCLUSIONS. Bosentan reduces intraocular inflammation and has similar effects as dexamethasone in a rat model of EIU.