Antioxidant sericin averts the disruption of oocyte-follicular cell communication triggered by oxidative stress.

Antioxidants are free radical scavengers that increase oocyte quality and improve female fertility by suppressing oxidative stress. However, the related mechanisms remain unclear. The present study was designed to examine whether a reduction of oxidative stress from using the antioxidant sericin led to expanded cumulus cell (CC)-oocyte communication and oocyte developmental acquisition in a bovine model.

The strong anti-hyaluronidase effect of ellagic acid markedly decreases polyspermy during in vitro fertilization, resulting in sustainment of the developmental potency in porcine oocytes.

The present study investigated the effects of ellagic acid, a type of polyphenol that does not have a glycan and is composed of four hydroxyl groups and two lactone functional groups, on porcine in vitro fertilization (IVF) by focusing on its anti-hyaluronidase activity. A comparative analysis of ellagic acid and apigenin, which is commonly used as a hyaluronidase inhibitor, was performed. It compared the effects of ellagic acid and apigenin on hyaluronidase activity at different concentrations.

Antifreeze protein type III addition to freezing extender comprehensively improves post-thaw sperm properties in Okinawan native Agu pig.

Sperm cryopreservation often leads to physical cell damage through ice crystal formation. This study evaluates the improvements to freezing extender cryoprotective activity due to antifreeze protein (AFP) addition, which primarily acts on ice crystal formation, through investigating the post-thaw sperm properties of Okinawan native Agu pig. Six individual boar sperm samples were diluted with the freezing extender supplemented with 1 μg/mL of AFP I or AFP III and then subjected to cryopreservation.

Effect of E-64 Supplementation during In Vitro Maturation on the Developmental Competence of Bovine OPU-Derived Oocytes.

Recovery of bovine oocytes using the ovum pick-up (OPU) technique offers the advantage of rapid genetic improvement through propagation of desired genes from animals with high genetic qualities. However, the developmental competence of OPU-derived immature oocytes remains relatively poor. We previously found that cathepsin B gene expression and activity are increased in poor quality oocytes and embryos compared to good quality ones.

Addition of l-carnitine to the freezing extender improves post-thaw sperm quality of Okinawan native Agu pig.

The objective of the present study was to establish whether the addition of l-carnitine (LC), which exhibits antioxidant activity, to the freezing extender improves the quality of cryopreserved Okinawan native Agu pig sperm. Ejaculated sperm frozen in an extender supplemented with 0, 1, 2.5, or 5 mM LC was thawed, and the integrities of mitochondria and the plasmalemma and other sperm characteristics were evaluated.

Gene expression of bovine endometrial epithelial cells cultured in matrigel.

Glandular epithelial cells (GE) in the endometrium are thought to support the elongation and survival of ruminant embryos by secreting histotrophs. In the present study, the gene expression of bovine endometrial epithelial cells cultured in matrigel was analyzed and examined whether it could be an in vitro model of GE. Bovine endometrial epithelial cells (BEE) and stromal cells (BES) were isolated from the slaughterhouse uteri and cultured in DMEM/F12 + 10% FBS.

Effectiveness of endoscopic hemostasis in preventing diverticular bleeding with extravasation detected by contrast-enhanced computed tomography: A single-center retrospective cohort study.

In diverticular bleeding, extravasation detected by computed tomography indicates active bleeding. It is unclear whether an endoscopic procedure is the best method of hemostasis for diverticular bleeding. This retrospective study was conducted to examine the effectiveness of endoscopic hemostasis in preventing diverticular rebleeding with extravasation visualized by contrast-enhanced computed tomography.

Study of Excited States and Electron Transfer of Semiconductor-Metal-Complex Hybrid Photocatalysts for CO Reduction by Using Picosecond Time-Resolved Spectroscopies.

A semiconductor-metal-complex hybrid photocatalyst was previously reported for CO reduction; this photocatalyst is composed of nitrogen-doped Ta O as a semiconductor photosensitizer and a Ru complex as a CO reduction catalyst, operating under visible light (>400 nm), with high selectivity for HCOOH formation of more than 75 %. The electron transfer from a photoactive semiconductor to the metal-complex catalyst is a key process for photocatalytic CO reduction with hybrid photocatalysts. Herein, the excited-state dynamics of several hybrid photocatalysts are described by using time-resolved emission and infrared absorption spectroscopies to understand the mechanism of electron transfer from a semiconductor to the metal-complex catalyst.

Charge Trapping Process in Photoexcited Nitrogen-Doped Titanium Oxides.

We present a first-principles study on the structural changes induced by charge trapping that occurs after photoexcitation in nitrogen-doped titanium oxide (N-TiO). The charge trapping site and the corresponding K edge EXAFS spectra of Ti atoms were predicted and compared with those obtained by an experiment under ultraviolet (UV) light excitation. The results indicate that charge trapping occurs in the neighborhood of the oxygen vacancy (O-vac) sites.

Introduction of gastric endoscopic submucosal dissection and skill acquisition in a regional hospital.

Background And Aim: Endoscopic submucosal dissection (ESD) is standard treatment for early gastric cancer. With aging of the population in Japan being more pronounced in rural areas, the availability of ESD at regional hospitals is becoming important. Here, we assessed the learning curve of one physician for skill acquisition in gastric ESD.

Endoplasmic reticulum stress attenuation promotes bovine oocyte maturation in vitro.

We have previously reported that regulation of endoplasmic reticulum (ER) stress during in vitro culture acutely increases bovine embryo developmental rate and cryotolerance; these data indicate that ER stress is a critical factor reducing the quality of in vitro-produced embryos. In the current follow-up study, we examined whether ER stress attenuation during in vitro maturation influences meiotic maturation, oocyte quality, and subsequent embryonic development. Bovine cumulus oocyte complexes (COCs) derived from slaughterhouse ovaries were matured with or without tauroursodeoxycholic acid (TUDCA), a selective inhibitor of ER stress (0, 50, 100, and 200 µM) for 22 h followed by in vitro fertilization, and zygotes were cultured for 8 days.

Bovine sperm selection procedure prior to cryopreservation for improvement of post-thawed semen quality and fertility.

Background: The application of cryopreservation and artificial insemination technology have contributed to the advancement of animal reproduction. However, a substantial proportion of spermatozoa undergoes alterations and loses their fertility during cryopreservation, rendering the frozen-thawed semen impractical for routine use. Cryopreservation is known to reduce sperm lifespan and fertility.

Role of endoplasmic reticulum stress on developmental competency and cryo-tolerance in bovine embryos.

Endoplasmic reticulum (ER) stress, a dysfunction in protein folding capacity of the ER, is involved in many physiological responses including mammalian reproductive systems. Studies have shown that ER stress interferes with the developmental process of in vitro oocyte maturation and embryo development; however, little is known about its effects on bovine preimplantation embryonic development. In this study, we examined the effects of ER stress during IVC on developmental competency and cryo-tolerance in bovine embryos.

Efficient in vitro embryo production using in vivo-matured oocytes from superstimulated Japanese Black cows.

We examined whether the use of in vivo-matured oocytes, collected by ovum pick-up (OPU) from superstimulated Japanese Black cows, can improve the productivity and quality of in vitro produced embryos. The cows were superstimulated by treatment with progesterone, GnRH, FSH and prostaglandin F2α according to a standardized protocol. The resulting in vivo-matured oocytes were collected by OPU and used subsequently for the other experiments.

Simple separation of good quality bovine oocytes using a microfluidic device.

We fabricated a simple microfluidic device for separation of bovine oocytes based on the oocyte quality to improve the conception rate of in vitro fertilization (IVF) by using good quality oocytes. The microfluidic device separates oocytes based on sedimentation rate differences in a sucrose buffer, which is dependent on oocyte quality. The microfluidic device has a 700 µm width, 1 mm height, and 10 mm long separation channel.

Normal DNA methylation status in sperm from a somatic cell cloned bull and their fertilized embryos.

Epigenetic reprogramming confers totipotency even during somatic cell nuclear transfer (SCNT), which has been used to clone various animal species. However, as even apparently healthy cloned animals sometimes have aberrant epigenetic status, the harmful effects of these defects could be passed onto their offspring. This is one of the biggest obstacles for the application of cloned animals for livestock production.

Heat-shock-induced cathepsin B activity during IVF and culture compromises the developmental competence of bovine embryos.

Heat stress can cause significant reproductive dysfunction in mammals and previous studies report that expression and activity of cathepsin B (CTSB), a lysosomal cysteine protease, is negatively correlated with the developmental competence of bovine oocytes and embryos. However, the relationship between heat shock (HS) and CTSB remains largely unknown. Here, we investigated the effects of HS during IVF and early embryonic stages of IVC on CTSB activity and developmental competence in bovine embryos.

Live births from artificial insemination of microfluidic-sorted bovine spermatozoa characterized by trajectories correlated with fertility.

Selection of functional spermatozoa plays a crucial role in assisted reproduction. Passage of spermatozoa through the female reproductive tract requires progressive motility to locate the oocyte. This preferential ability to reach the fertilization site confers fertility advantage to spermatozoa.

Re(bpy)(CO) Cl Immobilized on Bipyridine-Periodic Mesoporous Organosilica for Photocatalytic CO Reduction.

This paper describes the physicochemical properties of a rhenium (Re) complex [Re(bpy)(CO) Cl] immobilized on a bipyridine-periodic mesoporous organosilica (BPy-PMO) acting as a solid support. The immobilized Re complex generated a metal-to-ligand charge transfer absorption band at 400 nm. This wavelength is longer than that exhibited by Re(bpy)(CO) Cl in the polar solvent acetonitrile (371 nm) and is almost equal to that in nonpolar toluene (403 nm).

Different thermotolerances in in vitro-produced embryos derived from different maternal and paternal genetic backgrounds.

The present study evaluated the effects of genetic backgrounds on the developmental competence and thermotolerance of bovine in vitro-produced (IVP) embryos. First, Holstein (Hol) and Japanese Black (JB) oocytes were fertilized with sperm from Hol, JB and a thermotolerant breed (Brahman), and in vitro development was evaluated when the embryos were exposed to heat shock on Day 2 (Day 0 = day of fertilization). Sperm genetic backgrounds affected the developmental competence in controls (P < 0.

Epigenetic analysis of bovine parthenogenetic embryonic fibroblasts.

Although more than 100 imprinted genes have already been identified in the mouse and human genomes, little is known about genomic imprinting in cattle. For a better understanding of these genes in cattle, parthenogenetically activated bovine blastocysts were transferred to recipient cows to obtain parthenotes, and fibroblasts derived from a Day 40 (Day 0 being the day of parthenogenetic activation) parthenogenetic embryo (BpEFs) were successfully obtained. Bovine embryonic fibroblasts (BEFs) were also isolated from a normal fertilized embryo obtained from an artificially inseminated cow.