Background: Despite considerable technological advancements, polyspermy remains a significant challenge in in vitro fertilization (IVF) procedures in pigs, disrupting normal embryonic development. Here, we aimed to determine whether optimal fertilization conditions reduce the polyspermy incidence in pigs. Methods: In vitro -matured oocytes were co-incubated with sperm according to a modified two-step culture system. Results: In the first experiment, oocytes were briefly co-incubated with sperm, washed in IVF medium, and then moved to fresh IVF medium for 5 or 6 h. Although the 6 h sperm-free cultured group had a higher penetration rate than the 5 h cultured group, the polyspermy rate significantly increased in the 6 h sperm-free cultured group. The gamete co-incubation period was either 20 or 40 min. The 40 min cultured group had a higher rate of blastocyst formation and number of total cells in blastocysts than the 20 min cultured group. In experiment 2, oocytes were inseminated with sperm separated by Pecroll treatment. Percoll treatment increased the rate of oocyte penetration and blastocyst formation compared to the control. In experiment 3, fertilized oocytes were cultured in 25 μL microdroplets (10 gametes/drop) or 500 μL (100 gametes/well) of culture medium in 4-well plates. The large volume of medium significantly reduced the number of dead oocytes and increased the rate of blastocyst formation compared to the small volume. Conclusions: Collectively, these results demonstrate that various fertilization conditions, including modified co-culture period, active sperm separation, and culture medium volume, enhance fertilization efficiency and subsequent embryonic development by decreasing polyspermy occurrence.

본 연구는 Sprague-Dawley 계통의 4주령 랫드에서 MSG의 반복경구투여 독성평가와 행동실험을 통해 어린랫드의 인지능력과 불안감에 미치는 영향을 평가하기 위해서 시행하였다. 시험군은 MSG 대신 distilled water를 투여한 대조군(Control, n = 4), MSG를 3 g/kg을 투여한 군(Low, n =4), MSG를 5 g/kg을 투여한 군(High, n = 4)으로 나누어 4주 동안 주5회 경구투여를 하였다. MSG의 안정성을 확인하기 위해 다음과 같은 관찰 및 검사를 하였다. 검사항목으로는 체중의 변화, 임상증상, 행동실험인 T-maze, Elevatedplus-maze와 혈액학적 검사, 혈청생화학적 검사, 병리조직 학적 검사를 관찰한 결과 모든 투여군 및 대조군에서 특이할 만한 임상증상과 체중변화는 관찰되지 않았으며, 폐사 및 빈사 동물은 시험 전 기간을 통하여 발견되지 않았다. 행동실험인 T-maze 결과 MSG 고용량 투여군에서 움직이는 횟수가 감소하다 증가하는 양상을 보였고, Elevatedplus-maze 실험에서는 MSG 고용량 투여군의 Open arm의 출입빈도가 증가하는 등 유의적인 변화가 나타났다. 혈액학적 검사 및 혈청생화학적 검사에서는 대조군과 비교 시 유의적인 변화가 관찰되었지만 그 수치가 정상범위 안에 포함되기 때문에 이상을 나타내지 않았다. 병리조직검사 또한 약간의 염증발생 소견이 나왔지만 정상범위 안에 포함되기 때문에 이상을 나타내지 않았다고 판단했다. 따라서, 어린랫드를 이용한 MSG의 반복투여 독성시험 결과 특이할만한 신체적인 변화는 나타나지 않았으나 고용량의 MSG 투여는 어린랫드에서 인지능력의 저하 및 행동의 불 안을 유발할 가능성이 있다고 사료된다.

A total of 25 strains of Flammulina velutipes were analyzed to identify the genomic regions responsible for producing white-fruiting body. NGS data was yielded by using Illumina Hiseq platform. Short reads were filtered by quality score and read length were mapped on the reference genome (KACC42780). Between the white- and brown fruitbody forming strains, we found 9376 SNPs, of which 8178 were non-polymorphic and 1198 were polymorphic. There is a high possibility that SNPs can be detected among the white strains as homozygous because white phenotype is recessive in F. velutipes. Thus, we constructed SNP matrix within 8 white strains. SNPs discovered between mono3 and mono19, the parental monokaryotic strains of 4120 strain (white), were excluded from the candidate. If the genotypes of SNPs detected between white and brown strains were identical with those in mono3 and mono19 strains, they were included in candidate as a priority. As a result, if more than 5 candidates SNPs were localized in single gene, we regarded as they are possibly related to the white color. In F. velutipes genome, chr08: 950kb-2650kb, chr09: 500kb-1400kb, chr09: 2800kb-4350kb, and chr11: 2450kb-3500kb regions were identified to be associated with white fruitbody forming.

Skin whitening products are commercially available for cosmetic purposes in order to obtain a lighter skin appearance. They are also utilized for clinical treatment of pigmentary disorders such as melasma or postinflammatory hyperpigmentation. Whitening agents act at various levels of melanin production in the skin. Oxidative modification of DNA, proteins and lipids by reactive oxygen species (ROS) plays a role in aging and disease, including skin damages. In this study, we present an natural whitening and antioxidant product that may decrease skin pigmentation and skin damages.

In order to examine the effects of four different light spectra (white, red, green, and blue) on the oocyte maturation, the change of reproductive parameters, via brain-pituitary-gonad (BPG) axis in grass puffer, were investigated. After exposure four different light spectra for 7 weeks, the abundance of gonadotropin-releasing hormone (GnRH) mRNA which is a type of seabream (sbGnRH) and two different subunit of gonadotropin hormones mRNAs, follicle-stimulating hormone (fshβ) mRNA and luteinizing hormone (lhβ) mRNA, were analyzed in the brain and pituitary. Histological analysis showed that the mature oocyte ratio in the green spectrum was higher than other light spectra-exposed groups. Gonadosomatic index (GSI) and oocyte developmental stage were also investigated in the gonad based on histological observations. GSI value with the presence of yolk stage oocytes was significantly increased in the green spectrum-exposed group when compared to that of the other light-exposed groups (white, red, and blue) (p˂0.05). The abundances of sbGnRH mRNA and fshβ mRNA in the green spectrum-exposed group were also significant higher than those of the other light spectra-exposed groups (p˂0.05). These results indicate that the maturation of oocyte in grass puffer can be accelerated by exposure to the spectrum of green. To better understand the molecular mechanism for the maturation of oocyte in grass puffer, further study examining the relationship between oocyte development and its related genes is required.

In order to examine the effects of four different light spectra (i.e., white, red, green, blue) on the oocyte maturation in grass puffer, the change of reproductive parameters via brain-pituitary-gonad (BPG) axis were investigated in this study. After exposure to four different light spectra for 7 weeks, the abundance of gonadotropin-releasing hormone (GnRH) mRNA which is a type of seabream (sbGnRH) and two different of subunit of gonadotropin hormones mRNAs, follicle-stimulating hormone (fshβ) mRNA and luteinizing hormone (lhβ) mRNA, were analyzed in the brain and pituitary. Gonadosomatic index (GSI) and oocyte developmental stage were also investigated in the gonad based on anatomical- and histological observations. GSI value was significantly increased in the green spectrum-exposed group when compared to that of the other light-exposed groups (i.e., white, red, blue), with the presence of yolk stage oocytes (p˂0.05). The abundances of sbGnRHmRNA and fshβ mRNA in the green spectrum-exposed group were also significant higher than those of the other light spectra-exposed groups(p˂0.05). However, there was no significant difference between the abundances of lhβmRNA in all light spectra-exposed groups. These results indicate that the maturation of oocyte in grass puffercan be accelerated by exposure to the spectrum of green. The sbGnRHmRNA and fshβ mRNA may play an important reproductive parameters role in the initiation of maturation of oocyte. To better understand the molecular mechanism for the maturation of oocytein grass puffer, further study examining the relationship between oocyte development and its related genes (e.g., sbGnRHmRNA and fshβmRNA) is required.