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Öğe Assessment of tebuconazole exposure on bovine testicular cells and epididymal spermatozoa(Akademiai Kiado Zrt, 2021) Kabakci, Ruhi; Kaya, Abdulkadir; Yiğit, Ayşe Arzu; Varisli, ÖmerThis study is the first to investigate the effects of tebuconazole (TEB) on the physiological functions of bovine testicular cells and epididymal spermatozoa. Motility and plasma membrane integrity of spermatozoa exposed to TEB (0.001-100 mM) were evaluated at different incubation times (0-6 h), while TEB-induced spermiotoxicity was assessed after 24 h in cell cultures. Testicular cells, obtained from the parenchyma of bovine testes, were seeded at 1.0 x 10(4) and 1.5 x 10(6) cells/well in 96- and 12-well culture plates and incubated for 48 h in culture media containing TEB (0.001- 100 mM) to evaluate cytotoxicity and hormone release, respectively. TEB did not affect the motility and plasma membrane integrity. However, significant spermiotoxicity occurred at higher TEB (1-100 mM) concentrations (P < 0.05) compared to control and lower doses. Although no dose caused cytotoxicity in testicular cells (P > 0.05), 1 and 100 mM TEB caused a significant increase in testosterone secretion (P < 0.05). As a result, high doses of TEB (1-100 mM) had slightly suppressive effects on spermatozoa; however, these doses had stimulatory effects on testosterone secretion by testicular cells. It appears that the disruption of hormonal homeostasis of testicular cells after TEB exposure may result in metabolic and especially reproductive adverse effects in bulls.Öğe Investigation of the Effects of Storage Period for Frozen Bull Semen on In Vitro Embryo Production(Kafkas Univ, Veteriner Fakultesi Dergisi, 2019) Akyol, Numan; Ertem, Talha Burak; Varisli, OmerThe aim of this study was to investigate some spermatological parameters of frozen Brown Swiss bull semen 32 years ago by flow cytometry and to determine how storage time in liquid nitrogen affects in vitro embryo production ratios. For this purpose, early necrotic, necrotic, viable and apoptotic spermatozoa concentrations were analyzed using the Flow Cytometry and then the in vitro fertilization abilities of these sperms were investigated. AnnexinV/PI-FITC (R) was used to determine the apoptotic changes with flow cytometric analysis. Oocytes were obtained from slaughtered cows in a local abattoir. Brown Swiss semen, frozen in the last two years, were used for the control group. Early necrotic spermatozoa levels in semen frozen 32 years ago were lower but necrotic spermatozoa levels were higher than in the control group, but the opposite result was encountered in the control group (P<0.01) according to flow cytometry findings. The cleavage ratio in vintage spermatozoa was found to be lower than in the control group (P<0.0z), the blastocyst ratio was also lower than in the control group (P<0.01). As a result, it was observed that some spermatological parameters can be changed negatively and it can be said that a long storage period may lower the fertility capabilities of Brown Swiss bull semen.Öğe Effects of different extenders and additives on liquid storage of Awassi ram semen(Scientific Technical Research Council Turkey-Tubitak, 2018) Varisli, Omer; Taskin, Abdullah; Akyol, NumanThe aim of this study was to evaluate the effects of different extenders and additives on ram semen during liquid storage and to demonstrate the role of oxidative stress parameters on this process. In the present study, ejaculates taken by artificial vagina twice a week from 4 rams during the breeding season were used. They were mixed and used if motility and viability were above 70% and there was a 95% intact acrosome. The semen specimens were diluted by Tris-citrate-glucose (TRIS), Tris-TES (TEST), HEPES-buffered Tyrode lactate (TL-HEPES), and Dulbecco's phosphate-buffered saline (PBS) extenders supplemented with different additives [centrifuged egg yolk, Equex-STM, bovine serum albumin (BSA), and ethylenediaminetetraacetic acid (EDTA)]. The specimens were stored at 4 degrees C for up to 96 h and evaluated for motility, membrane integrity, acrosome integrity, mitochondrial membrane potential (MMP), and oxidative stress parameters. At the end of the 96-h storage, the highest sperm motility was 64.2 +/- 3.7% (P < 0.05) and significant loss of sperm motility and membrane integrity were not detected in extender TEST-3, but the MMP rate significantly declined. Acrosome integrity was not affected by storage time or extender types. BSA and EDTA decreased lipid peroxidation (LPO) and total oxidant status (TOS), but did not positively affect motility or membrane integrity. As a result, TRIS, TEST, and TE-FIEPES-3 were observed to provide better protection for ram semen during liquid storage at 4 degrees C than other extenders. The role of oxidative stress and MMP are considerable in liquid storage.Öğe Effects Of Long-Term Storage On Some Spermatological Parameters In Cryopreserved Bull Semen(Cryo Letters, 2018) Akyol, Numan; Varisli, Omer; Kizil, Sedat HamdiBACKGROUND: The effect of the long-term storage in liquid nitrogen on semen quality has not be reported. OBJECTIVE: The study measured the spermatological parameters of bull sperm after the long-term and short-term storage. MATERIALS AND METHODS: Vintage semen (obtained from 5 Brown Swiss bulls and frozen 30 years ago) and newly frozen semen collected from 5 bulls of the same breed and prepared at the International Center for Livestock Research and Training were used. For each bull, 10 straws (0.25 ml) were thawed and pooled. Sperm samples were analyzed by flow cytometry, computer assisted sperm analysis, and total oxidant-antioxidant levels were also tested. RESULTS: The ratios of necrotic (P < 0.001) and apoptotic (P = 0.006) spermatozoa, and the ratios of total antioxidant status (TAS) and total oxidant status (TOS) were significantly higher (P < 0.001) in long-term frozen spermatozoa. However, the early necrotic ratios (P < 0.001), velocity average pathway (VAP) (P = 0.008) and velocity curvi linear (VCL) (P = 0.01) values of long-term frozen semen were lower compared with short-term frozen semen. While necrotic and apoptotic spermatozoa ratios and total oxidant level were higher, VAPNCL ratios were lower in long-term frozen sperms compared to short-term frozen semen. CONCLUSION: Long-term storage of sperm may adversely affect the spermatological and oxidative parameters of Brown Swiss bull spermatozoa.Öğe The results of consecutive superovulations in cows by induction with various exogenous progesterone routes(Scientific Technical Research Council Turkey-Tubitak, 2014) Akyol, Numan; Kizil, Sedat Hamdi; Satilmis, Muharrem; Karasahin, Tahir; Erat, SerkanThe aim of this study was to determine the possibility of yielding more transferable embryos from cows superovulated with/without exogenous progesterone (ear implant and intravaginal device). Two experiments were conducted in Holstein Friesian cows to evaluate the effect of exogenous progesterone on the yield of corpus luteum (CL), total embryo and ova, and transferable embryos before superovulation. A superovulation program using 2 different progesterone resources was applied (G1 = intravaginal device, G2 = ear implant). Superovulation and uterus irrigations were done at 28-day intervals in the treatment groups. Cows in the control group were superovulated at 60-day intervals without application of exogenous progesterone. The mean numbers of CLs and transferable embryos for the G1, G2, and control groups were, respectively 4.82 +/- 0.29, 6.71 +/- 0.29, and 7.81 +/- 0.31 for CLs and 0.86 +/- 0.35, 3.50 +/- 0.35, and 1.53 +/- 0.39 for transferable embryos. It was shown that exogenous manipulation of the estrus cycle by progesterone could be applied without superovulation intervals in Holstein cows. It may also be postulated that the ear implant was more effective than the intravaginal device as a progesterone source in the superovulation program.Öğe Investigation of conception rates achieved with the transfer of sexed and unsexed bovine embryos(Scientific Technical Research Council Turkey-Tubitak, 2014) Karasahin, Tahir; Akyol, Numan; Satilmis, Muharrem; Kizil, Sedat Hamdi; Bucak, Mustafa Numan; Coyan, KenanThe objective of this study was to investigate the conception rates achieved with the transfer of in-vivo derived sexed and unsexed Holstein bovine embryos to appropriate recipients and to determine the accuracy of nonelectrophoretic PCR sexing. Seven-day-old embryos were derived in vivo by the nonsurgical flushing of the uterus. Before being vitrified and frozen some of the embryos obtained were sexed, while others were not sexed and were maintained as the control group. After thawing, the sexed and unsexed embryos were transferred to 23 and 21 bovine recipients, respectively. The conception rates achieved with the transfer of the sexed and unsexed embryos were 30.4% (7/23) and 42.9% (9/21), respectively. The difference between conception rates achieved in the 2 groups was not statistically significant (P > 0.05). For the sexed embryos the conception rates achieved with the transfer of male and female embryos were 27.2% (3/11) and 33.3% (4/12), respectively The accuracy of embryo sexing with nonelectrophoretic PCR was 66.6% for male embryos and 100% for female embryos postdelivery. The mean rate of accuracy determined for embryo sexing at the end of the study was 83.33%.Öğe Investigation of Bull Effect on in vitro Embryo Production(Kafkas Univ, Veteriner Fakultesi Dergisi, 2014) Akyol, Numan; Kizil, Sedat Hamdi; Satilmis, Muharrem; Karasahin, TahirThe aim of the study was to show whether there were some differences among 9 Holstein bulls and within their replications on their ability of in vitro fertilization for in vitro embryo production as cleavage and coming into the blastocyst stage. Semen collected and frozen from nine Holstein bulls with satisfactory in vivo fertilization capabilities for artificial insemination was used for in vitro fertilization. Direct washing method by Brackett and Oliphant medium and 5 or 6 h incubation period were used for in vitro fertilization. Charles Rosenkrans medium was used for in vitro embryo culture. An atmosphere with a higher than 95% relative humidity, 39 degrees C, 5% CO2 and was used for all in vitro embryo production processes. Totally 2519 A and B quality oocytes were treated for in vitro embryo production. As a result statistically significant (P<0.05) variation was found for cleavage and blastocyst development among bulls. However there was no significant difference (P>0.05) between the replications for each bull as cleavage and coming into blastocyst stage. The results showed varied capabilities of bulls for in vitro fertilization and embryo production and male factor can affect success of in vitro embryo production.Öğe The design of an embedded spinal cord stimulator(Tubitak Scientific & Technical Research Council Turkey, 2014) Yalcinkaya, Fikret; Erbas, AliSpinal cord stimulation is a physical therapy methodology utilizing electrical impulses, pulses, or a combination of various standard electrical waveforms to block pain. However, standard forms are not functioning effectively for each illness due to the unique conditions of the patient. Therefore, patient-specific waveforms (or user-defined waveforms) integrated with nondestructive, complete, or partially noninvasive and effective medical instruments to help relieve pain are required. In the literature, 2 different designs have been discussed: the bedside/portable and the implantable/surgical types. This work is introducing a new hybrid type: a portable touch-screen multichannel embedded spinal cord stimulator. This work is made of 3 parts: the hardware and the software designs, and an embedded interface introducing the system to external medical systems or patients. The hardware and software designs are explained in detail. The S3C2440 microprocessor-based embedded spinal cord stimulator generates not only 6 standards types of signals, but also user defined waveform(s). This requires medical experts' close relation, consultation, and cooperation with biomedical engineers who are able to design and develop new instruments with new requirements. In this paper, a microprocessor-based spinal cord stimulator is developed in the Samsung S3C2440 environment and PIC18F452-based channel boards. The S3C2440 environment is the main controller unit and the therapy signal is produced by the channel boards as a signal generator. The software is prepared by MS Visual Studio 2008 and Hi-Tech C. The frequency, duty-cycle, and amplitudes of the pulses can be altered by software control. The architecture of the stimulators is designed to be modular; therefore, its different blocks can be reused as standard building blocks. The designed and developed embedded spinal cord stimulator enables both home and bedside health care. The system is battery-operated, portable, user-friendly, and cost-effective.Öğe Gene expression profiles of vitrified in vitro- and in vivo-derived bovine blastocysts(Wiley, 2012) Aksu, Digdem Aktoprakligil; Agca, Cansu; Aksu, Soner; Bagis, Haydar; Akkoc, Tolga; Caputcu, Arzu Tas; Agca, YukselVitrification is becoming a preferred method for pre-implantation embryo cryopreservation. The objective of this study was to determine the differentially expressed genes of in vivo- and in vitro-produced bovine embryos after vitrification. In vitro- (IVF) and in vivo-derived (IVV) bovine blastocysts were identified as follows: in vitro-produced fresh (IVF-F), in vitro-produced vitrified (IVF-V), in vivo-derived fresh (IVV-F), in vivo-derived vitrified (IVV-V). The microarray results showed that 53 genes were differentially regulated between IVF and IVV, and 121 genes were differentially regulated between fresh and vitrified blastocysts (P?Öğe Farklı dönemlerdeki in vivo üretilmiş sığır embriyolarında cinsiyetin dağılımının belirlenmesi ve cinsiyetin bu dağılıma etkisinin araştırılması(2013) Karaşahin, Tahir; Satılmış, Muharrem; Kızıl, Sedat Hamdi; Akyol, NumanBu çalışmanın konusu, farklı dönemlerdeki in vivo sığır embriyolarının cinsiyetlerinin non elektroforetik PCR yön- temi ile tespit edilerek, cinsiyet dağılımının ve bu dağılımın arasındaki farkların cinsiyetten etkilenip etkilenmediğinin belirlenmesidir. Cinsiyet tayini amacıyla yedi günlük toplam 65 adet in vivo üretilmiş embriyo kullanıldı. Embriyo elde etmek için rutin süperovulasyon yöntemleri kullanıldı. Tohumlamalardan yedi gün sonra cerrahi olmayan yöntemle uterus yıkaması yapılarak embriyolar toplandı. Elde edilen embriyolar kalite değerlendirmesinin ardından cinsiyetleri tespit edildi. Embriyoların trophektoderm kısmından mikro manipülatöre bağlı mikro bıçak ile %10-30 oranında bir par- ça kesilerek biyopsi materyali alındı. Embriyodan biyopsi alma işlemi %20 FCS içeren D-PBS solüsyonu içerisinde yapıldı. Alınan biyopsi parçaları, lizis ve denaturasyon işlemleri amacıyla PCR cihazına yerleştirildi. Lizisi takiben DNA amplifikasyon işlemi 35 döngü olarak gerçekleştirildi. PCR cihazından çıkarılan tüpler, 302-312 nm dalga boyunda ışık veren UV lamba altında incelendi. Pembe renk veren embriyo “erkek embriyo” olarak belirlendi. Cinsiyet tayini yapılan embriyolardan kompakt morula aşamasında olan 30 embriyodan 14’ünün erkek (%46.7; 14/30), 16’sının dişi (%53.3; 16/30) cinsiyette; blastosist aşamasındaki 35 embriyodan 21’inin erkek (%60.0; 21/35), 14’ünün dişi (%40.0; 14/35) cinsiyete sahip olduğu tespit edildi. Blastosist aşamasındaki erkeklerin oranının (%60.0) morula aşamasına (%46.7) göre daha yüksek bulunmasına rağmen aralarındaki farklılık istatistik önemde bulunmamıştır (P0.05).Öğe Değişik Ozmotik Basınç Düzeyleri ve Kryoprotektif Maddelerin İvesi Koç Sperması Üzerine Etkisi(2014) Agas, İbrahim Halil; Varışlı, Ömer; Yurdaydın, NafizGünümüzde koyunlarda dondurulmuş sperma ile yapılan tohumlamalardan yeterli oranda fertilite elde edilememektedir. Dondurma işlemi esnasında spermatozoa değişik oranlarda ozmotik basınç ve ısı stresine maruz kalır. Spermatozoa üzerinde oluşan bu olumsuz etkilerin azaltılması için dondurma metotları ve yeni sulandırıcılar denenmektedir. Bu çalışmanın amacı, anizo-ozmotik ortam ve kryoprotektanların ivesi spermatozoonları üzerine olan etkisini motilite, membran ve akrozom bütünlüğü yönünden değerlendirmektir. Sunulan araştırmada; çiftleşme sezonu içerisinde olan iki adet ivesi koçtan suni vajen yöntemiyle alınan ejakülatlar birleştirilip kullanıldı. Çalışma iki aşamadan oluşmaktadır. Birinci aşamada; sperma 75, 150, 225, 325, 425, 600 ve 9005 miliosmollük (mOsm)/kg sükroz solüsyonuna 5 dakika maruz bırakılıp yeniden izo-ozmotik duruma getirildi. İkinci aşamada, sperma 0.5, 1.0 ve 1.5 M gliserol (Gly), dimetilsülfoksid (DMSO), etilen glikol (EG) ve propilen glikol (PG) içeren solüsyonlara 5 dakika maruz bırakılıp yeniden izoozmotik duruma getirildi. Spermalar motilite, membran ve akrozom bütünlüğü yönünden değerlendirildi. Koç spermatozoonlarının motilitesi, izo-ozmotik olmayan stres faktörlerinden önemli derecede etkilendi (P0.05). Genel olarak spermatozoa akrozom bütünlüğünü izo-ozmotik olmayan ortamdan etkilenmezken, 75 mOsm'lük sükroz solüsyonu akrozom bütünlüğünü önemli oranda düşürdü. Kryoprotektanların spermaya eklenmesi ve uzaklaştırılması motilite ve akzorom bütünlüğünü (0.5 M Gly hariç) önemli derecede etkiledi (P0.05). Sonuç olarak, İvesi koç spermasının çeşitli stres faktörlerinden değişik ölçüde etkilendiği gözlenmiştir.
