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https://hdl.handle.net/20.500.12587/17949

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Bilayer wound dressing composed of asymmetric polycaprolactone membrane and chitosan-carrageenan hydrogel incorporating storax balsam
(Elsevier, 2024) Nakipoglu, Mustafa; Özkabadayı, Yasin; Karahan, Siyami; Tezcaner, Ayşen
A comprehensive approach is needed to develop multifunctional wound dressing that is simple yet efficient. In this work, Liquidambar orientalis Mill. storax loaded hydroxyethyl chitosan (HECS)-carrageenan (kC) based hydrogel (HECS-kC) and polydopamine coated asymmetric polycaprolactone membrane (PCL-DOP) were used to develop a multifunctional and modular bilayer wound dressing. Asymmetric PCL-DOP membrane was prepared by non-solvent induced phase separation (NIPS) followed by polydopamine coating and demonstrated an excellent barrier against bacteria while allowing permeability for 5.45 ppm dissolved-oxygen and 2130 g/m2 water vapor transmission in 24 h in addition to 805 kPa tensile strength. Storax loaded HECS-kC hydrogel, on the other hand, demonstrated a pH-responsive degradation and swelling to provide necessary conditions to facilitate wound healing. The hydrogels showed stretchability above 140 %, mild adhesive strength on sheep skin and PCLDOP membrane, while the storax incorporation enhanced antibacterial and antioxidant activity. Furthermore, rat full-thickness skin defect model showed that the developed bilayer wound dressing could significantly facilitate wound healing compared to TegadermTM and control groups. This study shows that the bilayered wound dressing has the potential to be used as a simple and effective wound care system.
The impact of bone marrow-derived mesenchymal stem cells on experimental testicular torsion in rats
(Tubitak Scientific & Technological Research Council Turkey, 2022) Ertürk, Ahmet; Demir, Sabri; Günal, Yasemin Dere; Zengin, Mehmet; Çınar, Miyase; Yıldız, Dinçer; Karahan, Siyami
Background/aim: The aim of this study was to investigate the healing effects of bone marrow-derived mesenchymal stem cells (BM-MSCs) on experimental testicular torsion in rats. Materials and methods: Three groups consisting of 10 Wistar albino rats were created. In Group I, the left testicle was explored and relocated in the scrotum without any attempt to modify it. In Group II, the left testicle underwent torsion for three h and then was detorsed and relocated. In Group III, in addition to torsion and detorsion, BM-MSCs were administered intratesticularly. The rats were sacrificed on the seventh day, and the healing status of the testicles was investigated with histopathological and biochemical analyses. BM-MSC involvement was investigated by immunofluorescence microscopy. Statistical analysis was performed using SPSS 15.0. A p-value < 0.05 was considered statistically significant for all variables. Results: Immunofluorescence microscopy showed that BM-MSCs were located around the Leydig cells in Group III. Under light microscopy, the mean Johnsen Score of Group III was significantly higher than that of Group II (p = 0.035). The interleukin-10 (IL-10) level was significantly higher in Group III compared to Group II (p = 0.003). While the malondialdehyde (MDA) values in Group I (the control group) were lower than in the other groups (p = 0.037), the superoxide dismutase (SOD) values were similar (p = 0.158). Although there was no statistically significant difference between Group II and Group III in terms of MDA, it was lower in Group III. Although the tissue SOD levels were higher in Group III than in Group II, the difference was not statistically significant. Conclusion: This study has demonstrated that BM-MSCs significantly corrected the Johnsen Score and increased anti-inflammatory cytokine levels after testicular torsion. BM-MSCs can be used in testicular torsion as supportive therapy to minimize tissue damage.
Contribution of amniotic membrane to the healing of iatrogenic vas deferens injury
(Tubitak Scientific & Technological Research Council Turkey, 2021) Demir, Sabri; Ertürk, Ahmet; Zengin, Mehmet; Yıldız, Dinçer; Karahan, Siyami; Senel, Emrah
Background/aim: Iatrogenic vas deferens injury is one of the most serious complications of operations in the inguinal region. Vasovasostomy is performed as treatment. However, stenosis is common after vasovasostomy. Oligospermia or azoospermia may develop and result in infertility. This study aimed to investigate the effect of amniotic membrane on healing in vas deferens injuries. Materials and methods: Four groups consisting of 10 rats each were formed. No procedure was performed in Group-I. In Group -II, the left vas deferens was transected and left to spontaneous healing. In Group-III, the left vas deferens was transected, and end -to-end anastomosis was performed. In Group-IV, the left vas deferens was transected, end-to-end anastomosis was performed, and it was closed with a wrapping of amniotic membrane on the anastomosis line. Rats were sacrificed after 60 days, and each left vas deferens was evaluated. Lumen patency was checked by passing methylene blue through the vas deferens. Subsequently, the vas deferens was evaluated both macroscopically and histopathologically. Data were evaluated using SPSS version 21.0. p < 0.05 was considered statistically significant for all variables. Results: The anastomosis lines in Group-IV healed better than those in Group-III, and less stenosis was observed. There were differences between the groups in terms of luminal patency (p = 0.009), adhesions to surrounding tissues (p = 0.02) and separation of the ends of the vas deferens (p = 0.03). Conclusion: We observed improvement on luminal patency and histology of rat vas deferens injury after surrounding human amniotic membrane on the transected and repaired surface. Further studies are needed to apply this promising result on human beings.
Assessment of erythrocyte morphology in patients with type 2 diabetes mellitus: a pilot study of electron microscopy-based analysis in relation to healthy controls
(Tubitak Scientific & Technological Research Council Turkey, 2021) Mortaş, Tülay; Durmaz, Şenay Arıkan; Sezen, Şaban Cem; Savranlar, Yasemin
Background/aim: The present study aimed to assess erythrocyte morphology in newly diagnosed type 2 diabetes mellitus patients using scanning electron microscopy. Materials and methods: In total, 30 patients admitted to endocrine outpatient clinics were included in the study. The patients were divided into two groups according to their fasting blood glucose levels: type 2 diabetes mellitus (n = 15, fasting blood glucose levels >= 126 mg/dL) and control (n = 15, fasting blood glucose levels < 99 mg/dL). The patient's demographic characteristics, haemoglobin A1c levels, and scanning electron microscopy findings regarding erythrocyte morphology were recorded. Results: There was no significant difference between the control and type 2 diabetes mellitus group in terms of the participants' age (51.13 +/- 8.53 vs. 50.33 +/- 8.72 years, p = 0.8) and the male/female ratio (9/6 vs. 9/6). In the control group, discocytes were abundant, echinocytes were rare, and spherocytes were absent. On the other hand, discocytes were less common and echinocyte-shaped erythrocytes were more common in the type 2 diabetes mellitus group than in the control group. In addition, spherocytes were detected in the type 2 diabetes mellitus group. Moreover, the diameter of discocytes was significantly lower (p = 0.014), and blood glucose and haemoglobin A1c levels were significantly higher (p < 0.05 for both) in the type 2 diabetes mellitus group than in the control group. Conclusion: Our findings indicate that high glucose levels in type 2 diabetes mellitus patients lead to significant alterations in erythrocyte morphology, including decreased erythrocyte deformability and the formation of echinocytes and spherocytes due to eryptosis. The possibility of decreased erythrocyte deformability due to excessive eryptosis may disturb microcirculation in newly diagnosed, treatment-naive type 2 diabetes mellitus patients who do not have any complications.
Comparison of the effects of zinc-silver cream and Nigella sativa oil on wound healing and oxidative stress in the wound model in rats
(2020) Kumandaş, Ali; Karslı, Birkan; Kürüm, Aytül; Çınar, Miyase; Elma, Ertuğrul
The present study was undertaken to evaluate of Nigella sativa oil (NSO) and zinc-silver cream in a rat model of wound healing by means of clinical appearance, histopathology, oxidative stress parameters, and biomechanical tests. The rats were divided into three groups, each having twenty animals. Group 1 served as a control having wound. Other two groups received either NS oil or zinc-silver cream in addition to the wound. The study was initiated after the animals rested for 2 weeks for acclimation. Blood samples were collected from 10 randomly selected animals from each group at days 0, 3, 7 and 14 for oxidative stress measurements. Differences among groups for blood lipid peroxidation and antioxidant values were determined with respect to biochemical oxidative stress results (P<0.01). Wound sites of 10 animals from each group were allocated for histopathological examinations, and those of the remaining 10 animals from each group were used in biomechanical testing. Histopathological examination revealed that epithelization occurred in all groups. Inflammatory response with an intensive vascularization was present in the samples of the silver group (P<0.01). Consequently, zinc-silver group has differed positively in terms of biochemical and biomechanical and histological aspects compared to other groups for wound healing and oxidative stress.
Immunohistochemical expression of anti-oxidants in bovine oviduct epithelial cells of estral and luteal phases
(2016) Kürüm, Aytül; Deprem, Turgay; Kocamış, Hakan; Karahan, Siyami
Summary: The present study aimed to evaluate immunohistochemical distributions of anti-oxidative enzymes Cu Zn-Superoxide dismutase (SOD-1), catalase, and Glutation peroxidase-1 (GPX1) in the bovine oviduct epithelial cells of estral and luteal phases. The results indicated both ciliated and secretoric cells of the oviduct mucosa exibited varying degrees of immureactivity for all. The SOD-1 and GPX1 immunostainings were more conspicuous in luteal phase while catalase immunostaining was more apparent in estral phase, especially in the isthmus region of the oviduct. In contrast to catalase, GPX1 immunoractivity was absent or limited in the isthmus. All regions of the oviduct mucosa had similar SOD-1 immunoreactivity. SOD-1 and GPX1 immunoreactivities were more apparent in samples of the luteal phase while catalase immnureactivity was higher in those of the estral phase. Presence of anti-oxidative enzymes catalase, SOD, and GPX1 immunostainings in the bovine oviduct suggests that the bovine oviduct epithelial cells are most likely engaged into synthesis of such enzymes and possibly the source of anti-oxidative enzymes in oviduct fluid. The oviduct regions, each of which executes different reproductive functions, varied by means of catalase and GPX1 expressions, suggeting that anti-oxidants may possibly contribute to different physiological proceses in the reproductive cycle. Furthermore, anti-oxidant expressions also varied between luteal and estral phases, suggesting that oviduct epithelial cells are possibly influenced by hormonal changes in regard to anti-oxidant expression. Presence of SOD-1 immunoreactivity in some but not all basal cells of the oviduct epithelial lining should be further investigated for possible heterogeneities among basal cells and for origin of secretory and ciliated cells.
Koçlarda sinaptonema kompleksi' nin histomorfolojisi üzerinde araştırmalar
(2000) Ergün, Emel
Bu çalışmanın amacı, koçların primer spermatositlerinde sinaptonema kompleksi analizi ile kromozomların eşleşme davranışını incelemektir. Primer spermatositler için Counce ve Meyer'e ait mikroyayma tekniğinin modifikasyonu uygulandı. Bu uygulama ile hücre membranının yapısı bozularak, sinaptonema kompleksi'nin, iki boyutlu olarak üç paralel iplik şeklinde görülmesi sağlandı. Protein yapısındaki bu üçlü kompleks, bivalanlar boyunca şekillenmişti. Fosfotungstik asit boyamasından sonra, lateral elementler yoğun olarak boyandı ve bunların arasında daha zayıf boyanan sentral element ayırt edildi. Gümüş boyamasından sonra ise sadece lateral elementler görüldü. Bu çalışmada, iki profaz aşaması-zigoten ve pakiten- tanımlandı. Seks kromozomları geç zigotende eşleşmeye başladı.
Ankara tavşanlarında ekzokrin pankreasın histolojik yapısı
(2009) Şimşek, Nejdet; Ergün, Emel; Ergün, Levent
Bu çalışmada, Ankara tavşanlarının ekzokrin pankreası ışık ve elektron mikroskobik olarak incelendi. Tavşanlardan alınan pankreas örnekleri bouin ve gluteraldehit-paraformaldehit solüsyonlarında tespit edildi. Daha sonra bu dokular histolojik yöntemlerle işlenerek paraplast ve araldit M’de bloklandı. Işık ve elektron mikroskobik incelemelerde, ekzokrin pankreast, asiner hücreler ile küçük, orta ve büyük çaplı akıtıcı kanallar oluşturuyordu. Asinusu meydana getiren piramidal epitel hücrelerinin granüllü endoplazmik retikulum, krista tipi mitokondriyon, serbest ribozom ve elektron yoğun zimogen salgı granüllerinden zengin olduğu saptandı. Orta ve büyük çaplı akıtıcı kanalların lamina epitelyalis’i çoğunlukla prensipal hücreler, çok sayıda goblet hücresi ve az sayıda enteroendokrin hücreler, lamina propriya’sı ise müköz ve serömüköz bezler içermekteydi. Sonuç olarak, Ankara tavşanlarında ekzokrin pankreasın histolojik yapısı insan, rat, fare ve kedi gibi memelilere benzese de, akıtıcı kanallarında goblet hücreleri, müköz ve sero-müköz bezleri içermesi nedeniyle diğer memeli türlerinden farklı olduğu saptanmıştır. Bu nötral, asidik ve miks müsin içeren hücre ve bezlerin Ankara tavşanlarında ekzokrin pankreasın salgı metabolizmasına yardımcı olabileceği düşünülmüştür.
Ankara tavşanında konjunktiva ile ilişkili lenfoid doku
(2010) Bayraktaroğlu, Alev Gürol; Ergün, Emel; Beyaz, Feyzullah; Ertuğrul, Tuğrul
Bu çalışmada, Ankara tavşanında konjunktiva ile ilişkili lenfoid dokunun (Conjunctiva-associated lymphoid tissue, CALT) yapısı ışık ve elektron mikroskobik olarak incelendi. Araştırmada özel yetiştiricilerden sağlanan 10 adet sağlıklı, erişkin Ankara tavşanı kullanıldı. Asetik asit ile yapılan incelemede konjunktivanın lenfoid ve non-lenfoid bölgeler içerdiği gözlendi. Agregat lenf folliküllerinin nazolakrimal punktum çevresinde kümelendiği belirlendi. Histolojik olarak agregat lenf foliküllerinin epitele yakınlaştığı ve folikül ile ilişkili epiteli (Follicle-associated epithelium, FAE) oluşturduğu görüldü. Bu foliküller germinal merkez, korona, subepiteliyal dom bölgesi ve interfoliküler alanlardan oluşmaktaydı. Dom bölgesini örten FAE, kadeh hücresi içermeyen tek katlı yassı epitelden meydana gelirken; lenfoid yapı içermeyen bölge yapısında kadeh hücreleri bulunan yalancı çok katlı pirizmatik epitel ile örtülüydü. İnterfoliküler alanlarda ve folliküllerin dip kısımlarında yüksek endoteliyal venüllere rastlandı. İnce yapı düzeyinde, FAE’de elektron yoğun, ince ve dar bir sitoplazmaya sahip olan membranöz hücreler (M hücreleri) görüldü. Bu hücreler apikal membranında kısa ve düzensiz mikrofoldlar, sitoplazmasında vezikül ve vakuoller ile karakterizeydi. M hücrelerinin bazolateralinde ise lenfositler ve makrofajlar görüldü. Sonuç olarak, Ankara tavşanında CALT’ın, mukoza ile ilişkili lenfoid dokuların karakteristik özelliklerine sahip olduğu belirlendi.
Distribution and location of endocrine cells in the pancreas of the sparrowhawk, accipiter nisus
(2014) Kara, Adem; Tekiner, Deniz; Şimşek, Nejdet; Balkaya, Hülya; Özüdoğru, Zekeriya
Bu çalışmada, atmaca pankreasının dorsal, ventral ve splenik loblarında bulunan endokrin hücrelerin dağılımı immun- histokimysal metotlarla belirlenmiştir. Pankreas dokusu anti-glukagon, anti-insulin, anti-gastrin ve anti-somatostatin primer antikorları kullanılarak streptavidin-biotin peroxidase metodu ile boyandı. Çalışmada, glukagon (alfa hücresi), insülin (beta hücresi) ve somatostatin (delta hücresi) salgılayan hücrelerin splenik lobda sayısının en fazla olduğu saptandı. Atmalarda pankreasın endokrin bölümlerinin alfa, beta ve miks adacıklar halinde gruplaştıkları saptandı. Beta adacıklarının çok sayıda beta hücresi, az sayıda deltaalfa hücrelerini içerdiği belirlendi. Alfa adacıkları, genellikle alfa ve delta hücrelerinden nadiren de beta hücrelerinden oluşuyordu. Ayrıca, gastrin pozitif hücreler, sadece ekzokrin pankreasta 1 ya da 2-3 adet hücre grubu halinde bulunurken, seratonin pozitif hücrelere ise ekzokrin ve endokrin pankreasın herhangi bir bölümünde rastlanmadı. Sonuç olarak, atmaca pankreasının lop sayısı, endokrin adacık tipleri ve endokrin hücre lokalizasyonu açısından etçil kuşlarla benzerliği, evcil kuş türleriyle de farklılıkları belirlenmiştir.
Ankara tavşanında endokrin pankreas üzerine ışık ve elektron mikroskobik araştırmalar
(2010) Şimşek, Nejdet; Ergün, Emel; Ergün, Levent
Bu çalışmada, Ankara tavşanlarının (10 adet, sağlıklı ve erişkin) endokrin pankreası histokimyasal ve elektron mikroskobik olarak incelendi. Tavşanlardan alınan pankreas örnekleri Bouin, Carnoy ve gluteraldehit-paraformaldehit solüsyonlarında tespit edildi. Aldehit fuksin light green orange G (AF) ile histokimyasal olarak boyanan pankreas kesitlerinde 2 tip endokrin hücre belirlenmesine rağmen, elektron mikroskobik incelemelerde endokrin adacıkların A, B ve D hücrelerinden oluştuğu gözlendi. Langerhans adacıklarının merkezinde mor-menekşe boyanan çok sayıda B hücrelerinin ve periferinde sarımsı-yeşil boyanan az sayıda A hücrelerinin bulunduğu saptandı. Elektron mikroskobik olarak, A hücrelerinin salgı granülü genellikle yuvarlak ve elektron çok yoğun iken, B hücrelerinin sitoplazmasında salgı içeriği ile salgı membranı arasında belirgin boşluk bulunan elektron çok yoğun ve elektron az yoğun granüller tespit edildi. D hücrelerinin de elektron çok yoğun ve elektron az yoğun materyale sahip yuvarlak 2 çeşit granül içerdiği ancak, bu granüllerin A ve B hücrelerinin granüllerinden daha küçük olduğu gözlendi. Bu çalışmanın sonucunda, Ankara tavşanı endokrin pankreasının çok sayıda B hücreleri, az sayıda A hücreleri ve çok az sayıda da D hücrelerinden oluştuğu saptandı.
Akkaraman koyununda seksüel siklus süresince ovidukt epitelinde meydana gelen değişimlerin ışık ve elektron mikroskobik olarak incelenmesi
(2012) Kürüm, Aytül; Özen, Asuman
Bu araştırma, seksüel siklus süresince Akkaraman koyunu ovidukt epitelinde meydana gelen değişimlerin ışık ve elektron mikroskop düzeyde incelenmesi amacıyla yapılmıştır. Çalışmada 10 baş östral (folliküler evrede), 10 baş luteal ve 5 baş anöstrus döneminde olan toplam 25 baş sağlıklı, seksüel olgunluğa erişmiş Akkaraman koyununa ait oviduktun infundibulum, ampulla ve istmus bölgelerinden örnekler alındı. Işık mikroskobik incelemelerde, östral dönemde hücre boylarının daha yüksek olduğu, luteal dönemde hücre boylarının kısaldığı ve ampulla ile infundibulumda çekirdek atılışları gözlendi. Anöstrus dönemindeki bulguların diöstrus ile benzerlik gösterdiği saptandı. Yapılan histokimyasal boyamalarda östral dönemde ampulladaki sekretorik hücrelerde salgı miktarının arttığı belirlendi. Elektron mikroskobik incelemelerde östral dönemde özellikle ampulladaki sekretorik hücrelerde üç tip granüle rastlandı. Bunlar, açık renkli olan ve granül membranının altında dağınık orta yoğunlukta elektron koyu içeriğin bulunduğu birinci tip granüller, elektron koyu bir odak taşıyan ve bu odağın çevresinde konsantrik lamelli bir yapı sergileyen ikinci tip granüller olarak tanımlandı. Bu tip granüllerin bazılarında elektron koyu odağın ekzantrik olarak yerleştiği de gözlendi. Üçüncü tip granüller ise, elektron koyu odak taşımayan konsantrik lamelli granüller olarak belirlendi. Çalışma sonunda Akkaraman koyununda seksüel siklus süresince ovidukt epitelinde histolojik değişiklikler olduğu belirlendi. Sekretorik hücrelerde salgı miktarı ile salgı karakterinin, siklusun dönemlerin ve oviduktun bölümlerine göre değiştiği belirlendi.
Ankara tavşanı ince bağırsağında paneth hücrelerinin morfolojisi, histokimyası ve ince yapısı üzerinde çalışmalar
(2009) Ergün, Emel; Ergün, Levent; Özen, Asuman; Kürüm, Aytül
Bu araştırma, Ankara tavşanı ince bağırsağındaki Paneth hücrelerinin morfolojisini, histokimyasal özelliklerini, yerleşim bölgelerini ve sayısal dağılımını ortaya koymak amacıyla yapıldı. Çalışmada materyal olarak özel yetiştiricilerden sağlanan 10 adet sağlıklı, erişkin Ankara tavşanının duodenum, jejunum ve ileumlarından alınan doku örnekleri kullanıldı. Lieberhkühn kriptlerinde gözlenen Paneth hücreleri, bazalinde çekirdeği ve apikalindeki asidofilik granülleriyle tanındı. Granüller, Mallory’nin üçlü boyama tekniği, Phloxine-tartrazine, Alcian blue-performik asit ve Mallory’nin fosfotungstik asit-hematoksilen uygulamasına pozitif reaksiyon, Periyodik asit-Schiff (PAS), Alcian blue (pH 2.5), PAS-Alcian blue pH 2.5 boyamalarına ise negatif reaksiyon verdi. Paneth hücrelerinin ince bağırsağın tüm uzunluğu boyunca homojen bir dağılım göstermediği, hücre yoğunluğunun duodenumdan ileuma doğru gidildikçe arttığı gözlendi. İnce bağırsağın üç bölgesi arasındaki farkın istatistiksel olarak önemli olduğu (p<0.01) saptandı. Elektron mikroskobik incelemelerde bazı Paneth hücrelerinin apikal sitoplazmasında elektron yoğun ve homojen granüller, bazılarında ise elektron yoğunlukları farklı olan homojen granüller görüldü.
Mast cells in the dog skin: Distribution, density, heterogeneity and influence of fixation techniques
(2005) Astı, Resat Nuri; Kurtdede, Arif; Kurtdede, Nevin; Ergün, Emel; Güzel, Murat
Bu araştırma sağlıklı erişkin köpeklerde farklı deri bölgelerindeki mast hücrelerinin yerleşim yerlerini, morfolojilerini ve sayısal dağılımlarını incelemek amacıyla yapıldı. Çalışmada materyal olarak 10 adet sağlıklı köpeklerin yanak, kulak kepçesi, kaburga ve but bölgelerinden alınan deri örnekleri kullanıldı. Bulgularımız, alcian blue / safranin O ile boyanmasına ve formaldehit tespitine duyarlılığına göre köpek derisinde mâst hücre heterojenitesini gösterdi. Mast hücreleri bu parametrelerin dört kombinasyonu ile tanımlandı: Formole duyarlı sadece alcian blue-pozitif granüller içeren mast hücreleri, formole dirençli sadece alcian blue-pozitif granüller içeren mast hücreleri, formole dirençli sadece safranin O-pozitif granüller içeren mast hücreleri ve formole dirençli hem safranin O-pozitif hem de alcian blue-pozitif mikst granüller içeren mast hücreleri. Toluidin blue ile boyanmış kesitlerde dört bölgede de IF AA tespitli dokuların % 10 formolle tespit edilenlere göre daha fazla mast hücresi içerdiği dikkati çekti. Bu iki tespit arasında mm2'de mast hücre sayı ortalamalarındaki farklılığın istatistiksel olarak önemli (p<0.001) olduğu saptandı. Yanak bölgesinde yüzlek ve derin dermiş katmanlarında mm2'de ortalama mast.hücre sayıları istatistiksel olara:; önemsiz (p>0.05) iken, diğer üç bölgede istatistiksel fark önemli (p<0.001) bulundu. Kulak kepçesi, kaburga ve but bölgelerinde yüzlek katmanda derin katmana göre daha fazla mast hücresi bulunduğu saptandı. Her ikrtespitte de en fazla mast hücresi kulak kepçesi derisinde gözlendi (p<0.001).
Immunohistochemical distribution of glucagon -, insulin -, somatostatin -, gastrin-, and serotonin-containing cells in the pancreas of the Van cat
(2014) Karaca, Turan; Kara, Adem; Şimşek, Nejdet; Uslu, Sema; Tekiner, Deniz; Yörük, Mecit
The regional distribution, relative frequency, and appearance of glucagon (A-cell)-, insulin (B-cell)-, somatostatin (D-cell)-, gastrin (G-cell)-, and serotonin (EC-cell)-secreting cells in the endocrine and exocrine pancreas of Van cats were examined using the immunohistochemistry method. Glucagon immunopositive A-cells were principally found in the central region of the islets of Langerhans, while insulin immunopositive B-cells were located in the periphery of the pancreatic islets. Moreover, several A- and B-cells were observed as only single cells or clusters of 2 to 3 immunopositive cells in the exocrine parenchyma and the pancreatic duct epithelium. Somatostatin and gastrin immunopositive reactivities were negligible in the peripheral regions of the pancreatic islets of Langerhans and in the exocrine parenchyma. However, serotonin-immunopositive EC-cells were observed in neither the endocrine islets nor any other sites of the tissue. The existence, regional distribution, and relative frequency of A-, B-, D-, G- and EC-cells in the pancreas of Van cats have been analyzed in this study for the frst time. The immunopositivity and distribution of endocrine cells in the Van cat pancreas were determined to be partially diferent from those of other carnivorous species such as dogs and other cats.
Evaluation of melamine and cyanuric acid cytotoxicity: an in vitro study on L929 fibroblasts and CHO cell line
(ANKARA UNIV PRESS, 2020) Melekoglu, Abdullah; Ekici, Husamettin; Arat, Esra; Karahan, Siyami
Melamine and its metabolites pose health concern as they are used in various industrial products including feed and drugs. There are a limited number of studies on melamine and cyanuric acid cytotoxicity and cellular damage without a certain conclusion. The present study aimed to evaluate melamine, cyanuric acid and its combined cytotoxic effects using 3-(4.5-dimethylthiazol-2-yl) methyl thiazole tetrazolium (MTT) bromide test. The study also evaluated apoptotic and necrotic effect using a double staining method of Hoechst 33342 and propidium iodide. Melamine, cyanuric acid and their combination (1:1) were applied to L929 fibroblasts and Chinese hamster ovary (CHO) cells at various concentrations (1000 mu g/mL, 500 mu g/mL, 250 mu g/mL, 125 mu g/mL and 62.5 mu g/mL). At the highest concentration (1000 mu g/mL), the cell viability dropped down approximately to 50% both in CHO cells and L929 cells. Melamine, cyanuric acid and their mixture caused cytotoxicity in CHO cells and L929 fibroblasts in dose-dependent manner Cell death occurred through both apoptosis and mainly necrosis. Both cell types were more sensitive to the mixture of melamine and cyanuric acid and, furthermore, CHO cells were more sensitive than L929 fibroblasts. As a result, melamine, cyanuric acid and their combination caused cytotoxicity in CHO cells and L929 fibroblasts. Further studies should be conducted in different cell lines. These studies should also aim to reveal the mechanism of cytotoxicity and related pathways.
Determination of antioxidants in bovine oviduct epithelial cell culture isolated at different periods of the estrous cycle
(Scientific Technical Research Council Turkey-Tubitak, 2019) Kurum, Aytul; Karahan, Siyami; Kocamis, Hakan; Cinar, Miyase; Ergun, Emel
Oxidative stress interferes with oviduct functions including oocyte maturation, capacitation, fertilization, and embryo and gamete transport. This study aimed to determine activity of the antioxidants glutathione peroxidase (GPX-I), superoxide dismutase (SOD), and catalase (CAT) in bovine oviduct epithelial cells (BOEC) isolated from the isthmus and ampulla of the oviduct at estral (n = 7) and luteal phases (n = 7) of the estrous cycle. The antioxidant activity was measured at the primary, first, and second passages of the cell culture, and was characterized by cytokeratin expression. The GPX activity increased over the passages in samples of the ampulla and the isthmus of each sexual phase without statistical significance. The SOD activity remained steady through the cell passages in both sexual phases. CAT activity at the primary culture was higher in the ampulla compared to the isthmus in both sexual phases with a significant difference for the estral phase (P < 0.05), and it decreased over the passages with no significant differences. In conclusion, the antioxidant enzyme activity profile of BOEC did not differ by region or sexual cycle except for that of CAT, which was higher in the ampulla. Further studies should focus on SOD, GPX, and CAT activity for the mechanism of BOEC adaptation to an in vitro environment.
Autologous stem cell-derived chondrocyte implantation with bio-targeted microspheres for the treatment of osteochondral defects
(Bmc, 2019) Bozkurt, Murat; Asik, Mehmet Dogan; Gursoy, Safa; Turk, Mustafa; Karahan, Siyami; Gumuskaya, Berrak; Dogan, Metin
Background Chondral injury is a common problem around the world. Currently, there are several treatment strategies for these types of injuries. The possible complications and problems associated with conventional techniques lead us to investigate a minimally invasive and biotechnological alternative treatment. Combining tissue-engineering and microencapsulation technologies provide new direction for the development of biotechnological solutions. The aim of this study is to develop a minimal invasive tissue-engineering approach, using bio-targeted microspheres including autologous cells, for the treatment of the cartilage lesions. Method In this study, a total of 28 sheeps of Akkaraman breed were randomly assigned to one of the following groups: control (group 1), microfracture (group 2), scaffold (group 3), and microsphere (group 4). Microspheres and scaffold group animals underwent adipose tissue collection prior to the treatment surgery. Mesenchymal cells collected from adipose tissue were differentiated into chondrocytes and encapsulated with scaffolds and microspheres. Osteochondral damage was conducted in the right knee joint of the sheep to create an animal model and all animals treated according to study groups. Results Both macroscopic and radiologic examination showed that groups 3 and 4 have resulted better compared to the control and microfracture groups. Moreover, histologic assessments indicate hyaline-like cartilage formations in groups 3 and 4. Conclusion In conclusion, we believe that the bio-targeted microspheres can be a more effective, easier, and safer approach for cartilage tissue engineering compared to previous alternatives.
Morphology and quantification of sheep pineal glands at pre-pubertal, pubertal and post-pubertal periods
(Wiley, 2018) Bolat, Durmus; Kueruem, Aytuel; Canpolat, Sila
The pineal gland is a neuroendocrine organ associated with photoperiodic regulation in mammals. The aim of this study was to evaluate the pineal gland at the pre-pubertal, pubertal and post-pubertal periods by means of morphology and stereology. The study examined at total of 24 ovine pineal glands collected from healthy female Akkaraman breed. Thick sections (40m) were cut and treated with synaptophysin. Following each thick section, six consecutive sections at a thickness of 5m were cut. Each thin section was stained with one of the following dyes: Crossman's modified triple dye, glial fibrillary acidic protein (GFAP), melatonin marker, periodic acid-Schiff, Von Kossa and AgNOR. The pineal gland volume was measured using Cavalieri's method. The optical fractionator was used to estimate the total number of pinealocytes. The percentage of parenchyma and connective tissue and degree of vascularization were estimated by the area fraction fractionator method. The pineal gland volumes in the pre-pubertal, pubertal and post-pubertal groups were 7.53 +/- 1.715mm(3), 11.20 +/- 1.336mm(3) and 17.75 +/- 1.188mm(3), respectively (p<.5). The number of pinealocytes in the pre-pubertal, pubertal and post-pubertal groups was 3,244,000 +/- 228,076, 4,438,000 +/- 243,610, 7,381,766 +/- 406,223, respectively (p<.05). The glands of the post-pubertal group contained the highest amount of connective tissue (11.49 +/- 2.103%; p<.5) and the largest GFAP staining area (p<.05). The melatonin staining density was the highest in the pubertal group. The density of lipofuscin staining was higher in the pubertal and post-pubertal groups.
A comparative study of oculomotor, trochlear and abducens nerves in Arabian foals
(Taylor & Francis Inc, 2017) Bolat, D.; Yildiz, D.; Bahar, S.; Yuruker, S.; Kaymaz, F.; Ilgin, C.; Sabanci, S. S.
We investigated the microscopic structure of transverse sections of the oculomotor, trochlear and abducens nerves of Arabian foals using stereological methods. Bilateral nerve pairs from 2month-old female Arabian foals were analyzed. The tissues were embedded in plastic blocks, then 1 mu m thick sections were cut and stained with osmium tetroxide and methylene blue-azure II. Stereology was performed using light microscopy. Morphometry showed that the right and left pairs of nerves were similar. The transverse sectional areas of the oculomotor, trochlear and abducens nerves were 1.93 +/- 0.19 mm(2), 0.32 +/- 0.06 mm(2) and 0.70 +/- 0.08 mm(2), respectively. The oculomotor nerve exhibited a significantly greater number of myelinated axons (16755 +/- 1279) and trochlear (2656 +/- 494) and the abducens nerves (4468 +/- 447). The ratio of the axon diameter to myelinated nerve fiber diameter was 0.58, 0.55 and 0.55 for the oculomotor, trochlear and abducens nerves, respectively. Of the three nerves studied, the abducens nerve exhibited the greatest nerve fiber area, myelin area, nerve and axon diameters, and myelin thickness. The ratio of small myelinated nerve fibers was greatest in the oculomotor nerve.

Güncel Gönderiler