Embryo

Signalling interactions between the polarizing region, which produces SHH, and the apical ectodermal ridge, which produces FGFs, are essential for outgrowth and patterning of vertebrate limbs. However, mechanisms that mediate translation of early positional information of cells into ...

Cell microinjection is a technique of precise delivery of substances into cells and is widely used for studying cell transfection, signaling pathways, and organelle functions. Microinjection of the embryos of zebrafish, the third most important animal model, has become a very useful technique in bioscience. However, factors such as the small cell size, high cell deformation tendency, and transparent zebrafish embryo membrane make the microinjection process difficult. Furthermore, this process has strict, specific requirements, such as chorion softening, avoiding contacting the first polar body, and high-precision detection. Therefore, highly accurate control and detection platforms are critical for achieving the automated microinjection of zebrafish embryos. This article reviews the latest technologies and methods used in the automated microinjection of zebrafish embryos and provides a detailed description of the current developments and applications of robotic microinjection system...

Several critical variables associated with successful cryopreservation of oyster embryos (Crassostrea gigas) were examined. These were 1) embryo developmental stage, 2) kind and concentration of cryoprotectant, 3) equilibration time, and 4) freezing rate. The percentage of survival was scored as the number of recovered embryos that swam actively 12 h after thawing and had developed into veliger stage. The oyster

Preimplantation Genetic Diagnosis (PGD) is an alternative to prenatal diagnosis providing couples the chance to start a pregnancy with an unaffected fetus. The objective of the present study was to develop and apply quick, sensitive and accurate single cell PCR protocols for PGD of beta-thalassemia and Down's syndrome detection. Two couples carrying beta-thalassemia codon41-42 mutation underwent routine IVF procedures. Embryo biopsy was performed on Day-3 post-fertilisation and single cell multiplex fluorescent PCR was employed for mutation analysis, contamination detection and diagnosis of trisomy 21 cases. Seventeen embryos were tested in two clinical PGD cycles. This resulted in the first birth following PGD for a single gene disorder in Thailand and South East Asia, confirmed by prenatal testing. Two embryos were shown to be affected by Down's syndrome. Successful strategy for PGD of beta-thalassemia and Down's syndrome detection using multiplex fluorescent PCR was i...

To explore the potential for in vitro rapid regeneration of Parkia timoriana, a multipurpose tree legume, cotyledon explants were cultured on MS and B5 basal media supplemented with various concentrations of 2,4-D, NAA and BAP. Successful callus induction was observed in all the treatments. Maximum percentage of callus induction was obtained in the 2,4-D supplemented basal media. However, the overall response of MS medium was found to be superior to that of B5 medium. Explants cultured on MS medium fortified with combinations of 2,4-D and BAP induced rapidly proliferating calli that turned more friable and nodular. These protuberances eventually developed into somatic embryos when transferred in basal MS suspension medium without growth regulators. The protocol described here is the first on P. timoriana and has the potential to produce plantlets through somatic embryogenesis and also offers a highly efficient method for mass clonal propagation and conservation for this multipurpose...

To examine the relationship between endometrial thickness and outcome of medicated frozen-thawed embryo replacement (FER) cycles.A retrospective observational study.Assisted conception unit at a university hospital.All patients who underwent an FER cycle between 1997 and April 2006 and met the inclusion criteria.For endometrial preparation, a daily dose of 6 mg of oral E2 valerate was started on menstrual day 1, and P pessaries (800 mg daily) were administrated when the endometrial thickness had reached 7 mm or more, with ET taking place 2–3 days later. The FER cycles were categorized according to endometrial thickness measurement on the day of P supplementation.Implantation, clinical pregnancy, ongoing pregnancy, and live birth rates.In all, 768 consecutive medicated FER cycles were analyzed. The lowest pregnancy rates were associated with endometrial thickness <7 mm (n = 13) and >14 mm (n = 12; 7% in both groups). Significantly higher implantation (19% vs. 12%), clinical pregnancy (30% vs. 18%), ongoing pregnancy (27% vs. 16%), and live birth (25% vs. 14%) rates were achieved in cycles where endometrial thickness was 9–14 mm (n = 386), compared with those in which endometrial thickness was 7–8 mm (n = 357). These differences remained significant after adjusting for confounding variables (adjusted odds ratio [OR] = 1.83 [confidence interval {CI} = 1.3–2.6] for clinical pregnancy, 1.8 [CI = 1.2–2.6] for ongoing pregnancy and 1.9 [CI = 1.3–2.8] for live birth).In medicated FER cycles, an endometrial thickness of 9–14 mm measured on the day of P supplementation is associated with higher implantation and pregnancy rates compared with an endometrial thickness of 7–8 mm.

In the past four decades there have been tremendous changes in equine reproduction. Most breeds now allow the use of artificial insemination with fresh, cooled and frozen semen. Artificial insemination has many advantages for the breeder, in particular the control of bacteria through the use of semen extenders containing antibiotics. Deposition of sperm in small volumes onto the uterotubal junction has allowed the use of relatively low numbers of sperm. Intracytoplasmic injection of sperm into oocytes allows older, subfertile stallions to be used as breeding stallions. Advances in mare reproduction have included developing tools for hastening the onset of the breeding season. Other advances include embryo transfer, oocyte collection and transfer, and cloning. The acceptance of reproductive technology depends on the success of the technology, the attitude of the breeders/veterinarians, and the cost/benefit ratio to the industry and breed registry.

At a time when bioethical issues are at the top of public and political
agendas, there is a renewed interest in representations of the embryo in various religious
traditions. One of the major traditions that has contributed to Western representations of
the embryo is the Jewish tradition. This tradition poses some difficulties that may deter
scholars, but also presents some invaluable advantages. These derive from two components,
the search for limits and narrativity, both of which are directly connected with the manner
in which Jewish tradition was constructed in Antiquity.
The article accomplishes three goals:
􀁳􀀀 To introduce some central elements in ancient Rabbinic literature on the subject of
the embryo and its representation;
􀁳􀀀 To present this body of literature as clearly as possible, noting some of the difficulties
encountered by scholars who engage in its study;
􀁳􀀀 To explain how the literature’s textuality came about, examining the particular
sociopolitical circumstances of Judaism at that time, including the reasons for the
delay in the production of scientific texts, transmitted as such, as compared to other
philosophical or religious traditions.
The article claims that these circumstances engendered a tradition peculiarly relevant
for the study and teaching of medical ethics today.

This thesis describes a series of four experiments designed to evaluate the role of the supply of protein in livestock grazing high quality pasture during mating and during pregnancy. The first two studies investigated the effects of high crude protein content of spring or autumn re-growth pasture on the reproductive performance of dairy cows and of ewes at mating. The last two studies investigated how the dietary supply of protein, body condition and their interactions contribute to the breakdown of immunity during the peri-parturient period in ewes and investigated underlying endocrine mechanisms. In the first study (Chapter 3) cows were blood sampled via the tail vein during the breeding period in spring. Plasma was then analysed for urea concentration. Cows with high plasma urea (HPU) or low plasma urea (LPU) were defined as those with plasma urea concentrations of ≥ or &lt; 44.9 mg/dl respectively. Lactating cows (n = 200) were also categorized into high milk producers (HMP) or...