Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
Suggest a Journal
Articles by Tolga Akkoc
Total Records ( 4 ) for Tolga Akkoc
  Aygul Ekici , Digdem Aktoprakligil , Metin Timur , Tolga Akkoc and Haydar Bagis
  Green Fluorescent Protein (GFP) has been used as an indicator of transgene expression in living cells and organisms. In this study, a transgene construct containing the Cyto-Megalo-Virus (CMV) promoter sequences, SV40 polyA signal and the Enhanced Green Fluorescent Protein reporter gene (EGFP) was microinjected into the cytoplasm of one-cell zebrafish embryos. About 65 ng μL-1 circular and linearized pEGFP-N1 DNA was used in microinjection. Transgenic founders were detected by Polymerase Chain Reaction (PCR), Slot and Southern blots and Reverse-Transcriptase PCR (RT-PCR). EGFP gene expression was detected by inverted fluorescence microscope in F0 transgenic zebrafish larvae. About 54 and 25 F0 transgenic zebrafish were obtained after microinjection of linearized and circular gene constructs, respectively. This is the first study for generation of transgenic zebrafish via cytoplasmic DNA microinjection in Turkey. In conclusion, these results indicate that the gene expression efficiency of circular form was higher than the linearized form in F0 transgenic zebrafish larvae.
  Tolga Akkoc , Ali Cihan Taskin , Arzu Tas Caputcu , Sezen Arat and Haydar Bagis
  The aim of this study was to compare Solid Surface Vitrification (SSV) technique and classic vitrification technique in in vitro produced 8 days old bovine blastocysts. Cryopreservation of mammalian embryo has great importance for genetic resources conservation, embryo transfer, veterinary and clinical reproductive biotechnology and animal assisted reproductive technologies. Immature oocytes were maturated then fertilized with frozen-thawed bull semen and cultured until blastocyst stage in commercial sequential culture medium for 8 days. Blastocysts were vitrified in two different groups as SSV and classic vitrification and non-vitrified blastocysts were used as control group. After vitrification, vitrified blastocysts were warmed and cultured for 1 day. For this aim, blastocyst viability rate and median cell number were investigated. The blastocyst viability rate that vitrified by classic vitrification (34.8%) were found to be lower than those vitrified by SSV (82.6%) and control group blastocysts (100%). However, median cell numbers of vitrified-warmed blastocysts were found higher in SSV (124) than classic vitrification (104). Median cell number of control group was detected as 213. As a result, blastocyst viability rate and median cell number in SSV group was higher than classic vitrification group, there was a significant difference between SSV and classic vitrification group (p<0.05).
  Ali Cihan Taskin , Tolga Akkoc , Arzu Tas Caputcu , Sezen Arat and Haydar Bagis
  The researchers investigated the effect of blastocyst development and quality of blastomere aspiration techniques on eight-cell mouse embryos. The results clearly indicate that the in vitro development of biopsied mouse embryos depended on the suitable aspiration method. This method related to pre-implantation genetic diagnosis for the genesis of animal models for animal disorders from embryos. In this study, female CB6 F1(Balb/cXC57bl/j) hybrid mice were superovulated with hormones and superovulated females were sacrified approximately 68 h after hCG administration. About eight-cell embryos were recovered from oviducts of sacrified mouse in M2 medium. Before biopsy, all embryos were incubated to decrease cell to cell contacts to microdrops of Ca2+/Mg2 + free QAM HTF (3 mg mL-1 BSA Fraction V) with HEPES for 90 min at 37°C. A single blastomere of eight-cell embryos were aspirated by the aspiration pippetes under inverted microscope (4X). After biyopsy, embryos were cultured in SAGE medium supplemented with 5% CO2, 5% O2 and 90% air at 37°C for up to expanded blastocyst stage. After culture, 267 biopsied embryos out of 234 (88.32±7.5%) expanded blastocysts developed from the biopsy group and total cell number mean 67.8±17.2% were recorded in the experiment group and 126 non-biopsied embryos out of 118 (94.4±7.78%) expanded blastocysts developed from control embryos and total cell number mean 70±15.4% was recorded in the control group. In the present study, there was no difference in blastocysts developmental rates at post biopsy group and control group (p = 0.05). In conclusion, the biopsy the method described here is an optimal method of blastomere aspiration on in vivo mouse embryos.
  Mesut CEVIK , Arzu TAS , Tolga AKKOC , Haydar BAGIS and Sezen ARAT
  The objective of this study was to determine the effects of 3 chemical agents used sequentially and electrical stimuli on parthenogenetic activation of in vitro matured bovine oocytes and comparison with a standard IVF protocol for embryo developmental rates. For this purpose, oocytes were matured in tissue culture medium-199 (TCM-199) at 39 °C and 5% of CO2 in humidified air. For IVF, matured oocytes were fertilized in Modified Tyrode-Lactate Medium. In the parthenogenetic activation process, direct current (DC) was pulsed (133 V/500 mm) for 25 ms and oocytes were sequentially activated with calcium ionophore (CaI) for 10 min, cycloheximide (CHX) + cytochalasin D for 1 h, and CHX for 5 h. After that, all embryos (both IVF and parthenogenetic) were cultured in G1.3/G2.3 media containing 6% CO-2, 5% O2, and 89% N2 in humidified air at 39 °C. Cleavage rate was not significantly different following parthenogenetic activation compared to IVF (P > 0.05). Morula, blastocyst development, and blastocyst cell numbers were not also significantly different between parthenogenetic activation and IVF (P > 0.05). These results showed that bovine oocyte activation with electrical stimulation and chemical agents gave the desirable results, and the culture medium (G1.3/G2.3) supported both parthenogenetic and IVF embryo development.
Copyright   |   Desclaimer   |    Privacy Policy   |   Browsers   |   Accessibility