Analysis of the effects of blue light on morphofunctional status of in vitro cultured blastocysts from mice carrying gene of enhanced green fluorescent protein (EGFP)

The Task Matters: A Comprehensive Review and Proposed Literature Score of the Effects of Chemical and Physical Parameters on Embryo Developmental Competence

To explore the effects of chemical and physical parameters on embryo developmental competence, we conducted a systematic search on PubMed for peer-reviewed original papers using specific keywords and medical subject heading terms. Studies of interest were selected from an initial cohort of 4141 potentially relevant records retrieved. The most relevant publications were critically evaluated to identify the effect of these parameters on embryo development. Moreover, we generated a literature score (LS) using the following procedure: (i) the number of studies favoring a reference group was expressed as a fraction of all analyzed papers; (ii) the obtained fraction was multiplied by 10 and converted into a decimal number. We identified and discussed six parameters (oxygen, temperature, humidity, oil overlay, light, pH). Moreover, we generated a LS according to five different comparisons (37 °C vs. <37 °C; 5% vs. 20% oxygen; 5-2% vs. 5% oxygen; humidity conditions vs. dry conditions; light exposure vs. reduced/protected light exposure). Only two comparisons (37 °C vs. <37 °C and 5% vs. 20% oxygen) yielded a medium-high LS (8.3 and 7, respectively), suggesting a prevalence of studies in favor of the reference group (37 °C and 5% oxygen). In summary, this review and LS methodology offer semi-quantitative information on studies investigating the effects of chemical and physical parameters on embryo developmental competence.

Toxic effect of light on oocyte and pre-implantation embryo: a systematic review

In the female reproductive tract, oocytes and embryos are in a dark environment, while during the in vitro fertilization (IVF) they are exposed to various visible and invisible lights such as daylight, microscope, and laminar hood fluorescent lights. Studies have shown that light could damage cellular compartments of oocytes and embryos and consequently decrease rates of fertilization, development, and blastocyst formation. However, due to the lack of consensus about the effects of light on the embryos, and subsequently the inability to make definitive decisions regarding the light exposure management to improve IVF results, in the present study, we systematically reviewed the effect of light with different wavelengths and intensities on pre-implantation embryos. The toxic impact of light depends on the wavelength, intensity, and duration of light exposure and also the stage of embryo. Therefore, reducing the observation time of embryos out of the incubator and also using light filters can alleviate the detrimental effect of light in IVF labs.

Construction of recombinant pEGFP-N1-hPer2 plasmid and its expression in osteosarcoma cells

The aim of this study was to construct the eukaryotic expression vector pEGFP-N1-hPer2 and assess its expression in the human osteosarcoma cell line MG63. Total mRNA was extracted from human osteosarcoma MG63 cells, the human period 2 (hPer2) gene was obtained by reverse transcription-polymerase chain reaction (RT-PCR) and cloned into the pEGFP-N1 vector, then the recombinant pEGFP-N1-hPer2 plasmid was constructed and transfected into MG63 cells using Lipofectamine 2000. The expression of hPer2 in MG63 cells was measured by quantitative RT-PCR and western blot analysis. The accurate construction of pEGFP-N1-hPer2 was verified by double enzyme digestion and DNA sequencing. hPer2 gene expression in the transfected cells was assessed by RT-qPCR and western blot analysis. In conclusion, the recombinant pEGFP-N1-hPer2 plasmid was constructed successfully, and expressed effectively in MG63 cells.