Browsing by Author "Baykara, Mehmet"

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Changes in Expressions of ADAM9, 10, and 17 As Well as Alpha-Secretase Activity in Renal Cell Carcinoma
(2017) Erin, Nuray; Ipekci, Tumay; Akkaya, Bahar; Ozbudak, Irem Hicran; Baykara, Mehmet; https://orcid.org/0000-0002-2755-0526; https://orcid.org/0000-0001-6687-1587; 27692848; AAB-2986-2020; C-4815-2016
Background: ADAM9, 10, and 17 are a class of disintegrins and metallproteinases with oc-secretase activity. There are conflicting results regarding the role(s) of ADAM9, 10, and 17 in carcinogenesis, and only a few studies have examined their levels and cellular localization in renal cell carcinoma (RCC). Studies examining changes in oc-secretase activity in RCC compared to enzymatic activity of the uninvolved kidney are lacking. Method: A cross-sectional study was conducted in 56 patients undergoing radical nephrectomy after the diagnosis of RCC. alpha-Secretase activity was determined using flourogenic substrate in freshly frozen tumor tissues as well as similarly treated tissues from the neighboring kidney. Immunohistochemical analyses of ADAM9, 10, and 17 were also performed. Results: alpha-Secretase activity decreased markedly in all types of RCC as compared to neighboring uninvolved kidney tissue having 5 to 10 times higher levels of oc-secretase activity. Although type-dependent variations were observed, tumoral expressions of ADAMs, except for ADAM17, were lower in the tumors compared to that of neighboring tissues, but the changes in oc-secretase activity were greater. In RCC tissue, ADAM9 expressions were localized in nuclear and cytoplasmic compartments, whereas ADAM10 and 17 were present predominately in the cytoplasm potentially explaining the markedly decreased enzyme activity. Membranous localization of ADAMs was noted in uninvolved kidney tissue. Conclusions: The loss of alpha-secretase activity observed here in conjunction with previous findings argue against tumorigenic effects of ADAM9, 10, and 17 supporting that increased nuclear and cytoplasmic expression may be an attempt to compensate for loss of function. (C) 2017 Elsevier Inc. All rights reserved.
Primary Leiomyosarcoma of the Kidney: Four Cases
(2015) Akkaya, Bahar; Tuncer, Saniye Sevim; Akkaya, Hampar; Gurer, Elif Inanc; Baykara, Mehmet
Renal sarcomas are rare tumors. They constitute only 1-2% of malignant renal tumors in adulthood. Leiomyosarcoma is the most common histological type of renal sarcoma (50-60%). Renal leiomyosarcomas are aggressive tumors arising from the renal capsule, renal vein, pelvic musculature or the renal parenchyma. Diagnosis is usually post operative and requires a thorough sampling of the tumor to rule out an epithelial component. We report 4 new cases of primary renal leiomyosarcomas. Typical morphologic pattern shows alternating fascicles of spindle cells with blunt-ended, non-tapering nuclei and eosinophilic cytoplasm. Nuclear pleomprphisim atypia, mitotic figures and necrosis are seen in different ratios. Immunohistochemically the tumor cells of leiomyosarcoma are positive for SMA, desmin, calponin and h-caldesmon and negative for CK, S-100, HMB-45 and CD117. These tumors are classified using the French Federation of Cancer Centers System. To make a diagnosis of a primary renal sarcoma the following criteria should be met: 1) The patient must not have a sarcoma elsewhere to rule out metastasis. 2) Gross must be compatible with origin in the kidney rather than involvement due to retroperitoneal sarcoma. 3) Sarcomatoid renal cell carcinoma must be excluded. They usually have poor prognosis. But small size (<5 cm), low histological grade, absence of lymph node metastases and radical operations are all associated with better prognosis. Despite radical nephrectomy the tumors can run an aggressive clinical course and early local and distant recurrences are common.
Visual Outcomes at 12 Months in Patients Following Implantation of a Diffractive Multifocal Intraocular
(2015) Baykara, Mehmet; Akova, Yonca Aydin; Arslan, Osman Sevki; Cinhuseyinoglu, Necdet; Takmaz, Tamer; Gucukoglu, Ahmet; Usta, Yildirim Beyazit; 25825014
Introduction: The aim of this study was to assess distance, intermediate, and near visual acuity, contrast sensitivity, and patient satisfaction outcomes of a multifocal intraocular lens (IOL). Methods: This multicenter, prospective clinical study was conducted at seven study sites in Turkey. Patients who underwent bilateral cataract removal and implantation of a diffractive, acrylic, hydrophobic, multifocal IOL (Acriva UD Reviol MFB 625; VSY Biotechnology, Istanbul, Turkey) were included. The uncorrected and best corrected distance visual acuities (UCDVA and BCDVA), uncorrected and best corrected intermediate visual acuities (UCIVA and BCIVA), and uncorrected and best corrected near visual acuities (UCNVA and BCNVA) were measured preoperatively and at postoperative 1, 6, and 12 months. Distance and near visual acuity scores (VAS) contrast sensitivities were measured at these time points. Quality of life was evaluated by visual function-14 (VF-14) questionnaire. Results: Two hundred eyes of 100 patients were included. Monocular and binocular visual acuities at all distances showed improvement at postoperative 12 months compared to preoperative measurements (P < 0.001). Monocular and binocular UCIVA and binocular BCIVA at postoperative 12 months were significantly improved compared to measurements at 1 month (P < 0.001). Binocular contrast sensitivity at distance showed significant improvement from postoperative 1 month to postoperative 12 months, except for 3 cycles per degree (cpd; without glare) and 18 cpd (with glare). VAS improved from 75.96 at postoperative 1 month to 76.85 at postoperative 12 months. VF-14 score was 98.2 +/- 4.6. Conclusion: The Acriva UD Reviol MFB 625 appears to provide a good level of distance and near visual acuity, quality of life, and patient satisfaction. Further studies with longer follow-up will provide valuable insight into the long-term stability of these visual outcomes.