Dimethyl sulfoxide and glycerol as cryoprotectant agents of stallion semen: effects on blastocyst rates following intracytoplasmic sperm injection of IVM equine oocytes

2020 ◽  
Vol 32 (3) ◽  
pp. 253
Author(s):  
Nancy L. Cook ◽  
Keith R. Masterson ◽  
David Battaglia ◽  
Rick Beck ◽  
Elizabeth S. Metcalf
Keyword(s):  
Dimethyl Sulfoxide ◽  
Intracytoplasmic Sperm Injection ◽  
Semen Quality ◽  
Critical Examination ◽  
Blastocyst Development ◽  
Cleavage Rate ◽  
Recent Developments ◽  
Transvaginal Aspiration ◽  
Processing Techniques ◽  
Selection Of

Numerous variables affect invitro blastocyst development following intracytoplasmic sperm injection (ICSI). The paternal factor is affected by initial semen quality, processing techniques and final selection of individual spermatozoon for injection. This study investigated whether there was an effect of sperm cryoprotectant agent (CPA) on equine invitro blastocyst production, and reviews recent developments examining how processing equine semen affects ICSI outcomes. Single ejaculates from five stallions were collected and processed in a freezing extender containing either 1M dimethyl sulfoxide (DMSO) or 3.5% glycerol. Immature equine oocytes were obtained from ovarian follicles of mares during diestrus by transvaginal aspiration (n=128). After invitro maturation, MII oocytes (n=90) were fertilised by ICSI with thawed stallion spermatozoa (n=45 in both the DMSO and glycerol groups). The embryo cleavage rate was greater in the DMSO than glycerol group (73.3% vs 46.7% respectively; P=0.0098), but the blastocyst development rate per fertilised oocyte was similar between the two groups (28.9% vs 15.6% respectively; P=0.128), as was the blastocyst production rate per cleaved embryo (39.4% vs 33.3% respectively; P=0.653). In this study, cryopreservation of equine spermatozoa in 1M DMSO was correlated with significantly higher cleavage rates in IVM oocytes fertilised by ICSI compared with spermatozoa cryopreserved using 3.5% glycerol. Although not statistically significant in this small number of stallions, increased blastocyst production and individual stallion variability was observed among CPA treatments. This warrants further critical examination of cryoprotectants used in equine sperm subpopulations used for ICSI in a larger number of stallions.

Effects of negative pressure applied before storage (liquid storage, 17°C) on boar semen quality and fertilization ability

2019 ◽  
Author(s):  
LI. Jingchun ◽  
LI. Qi ◽  
LI. Yanbug ◽  
WEI Guosheng ◽  
SUN Dongbo
Keyword(s):  
Sperm Motility ◽  
Negative Pressure ◽  
Semen Quality ◽  
The Other ◽  
Blastocyst Development ◽  
Cleavage Rate ◽  
Liquid Storage ◽  
Fertilizing Ability ◽  
Boar Semen ◽  
Acrosome Integrity

The present study was aimed to investigate the effects of negative pressure applied before storage on the quality and fertilization ability of boar semen. Boar semen samples were collected and pooled, and diluted with Modena solution containing 0.4% (w/v) of bovine serum albumin. Negative pressure was applied for 2–5 min using a vacuum pump with a barometer. The pressure applied were 0 (Control), -0.02 MPa (P200), -0.04 MPa (P400), and -0.08 MPa (P800). The sperm motility, acrosome integrity and sperm fertilizing ability were evaluated. Application of –0.04 MPa improved the sperm motility, acrosome integrity and fertilizing ability, compared with the other groups. The sperm motility and acrosome integrity decreased with increasing storage time in vitro. After 5 days, the sperm motility and acrosome integrity of the P400 group were all higher than those of the other groups (P less than 0.05). The cleavage rate (64.5% ± 2.4%) and blastocyst development rate (33.9% ± 2.8%) for semen stored for 7 days were similar to those of fresh semen. In conclusion, application of –0.04 MPa before liquid storage at 17°C can improve the quality and fertilization ability of boar semen.

Oxford Studies in Metaethics Volume 15

2020 ◽  
Keyword(s):  
Philosophy Of Mind ◽  
Philosophy Of Language ◽  
Moral Realism ◽  
Ethical Theory ◽  
Philosophical Work ◽  
Moral Explanation ◽  
Recent Developments ◽  
Selection Of

This series is devoted to original philosophical work in the foundations of ethics. It provides an annual selection of much of the best new scholarship being done in the field. Its broad purview includes work being done at the intersection of ethical theory and metaphysics, epistemology, philosophy of language, and philosophy of mind. The chapters included in the series provide a basis for understanding recent developments in the field. Chapters in this volume explore topics including the nature of reasons, the tenability of moral realism, moral explanation and grounding, and a variety of epistemological challenges.

scholarly journals Microbial Electrochemical Systems: Principles, Construction and Biosensing Applications

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1279
Author(s):  
Rabeay Y.A. Hassan ◽  
Ferdinando Febbraio ◽  
Silvana Andreescu
Keyword(s):  
Electrode Materials ◽  
Electrical Power ◽  
Chemical Energy ◽  
Practical Implementation ◽  
Development Status ◽  
Electrochemical Systems ◽  
Recent Developments ◽  
Energy Environment ◽  
Microbial Electrochemical Systems ◽  
Selection Of

Microbial electrochemical systems are a fast emerging technology that use microorganisms to harvest the chemical energy from bioorganic materials to produce electrical power. Due to their flexibility and the wide variety of materials that can be used as a source, these devices show promise for applications in many fields including energy, environment and sensing. Microbial electrochemical systems rely on the integration of microbial cells, bioelectrochemistry, material science and electrochemical technologies to achieve effective conversion of the chemical energy stored in organic materials into electrical power. Therefore, the interaction between microorganisms and electrodes and their operation at physiological important potentials are critical for their development. This article provides an overview of the principles and applications of microbial electrochemical systems, their development status and potential for implementation in the biosensing field. It also provides a discussion of the recent developments in the selection of electrode materials to improve electron transfer using nanomaterials along with challenges for achieving practical implementation, and examples of applications in the biosensing field.

scholarly journals Recent advances in the electrochemical construction of heterocycles

2014 ◽  
Vol 10 ◽  
pp. 2858-2873 ◽  
Author(s):  
Robert Francke
Keyword(s):  
Heterocyclic Compounds ◽  
Elevated Temperatures ◽  
Ring Formation ◽  
Environmentally Benign ◽  
Heterocyclic Chemistry ◽  
Ambient Conditions ◽  
Recent Developments ◽  
Strong Acids ◽  
Selection Of ◽  
Made In

Due to the fact that the major portion of pharmaceuticals and agrochemicals contains heterocyclic units and since the overall number of commercially used heterocyclic compounds is steadily growing, heterocyclic chemistry remains in the focus of the synthetic community. Enormous efforts have been made in the last decades in order to render the production of such compounds more selective and efficient. However, most of the conventional methods for the construction of heterocyclic cores still involve the use of strong acids or bases, the operation at elevated temperatures and/or the use of expensive catalysts and reagents. In this regard, electrosynthesis can provide a milder and more environmentally benign alternative. In fact, numerous examples for the electrochemical construction of heterocycles have been reported in recent years. These cases demonstrate that ring formation can be achieved efficiently under ambient conditions without the use of additional reagents. In order to account for the recent developments in this field, a selection of representative reactions is presented and discussed in this review.

Digital platforms under fire: What Australia can learn from recent developments in Europe

2018 ◽  
Vol 43 (4) ◽  
pp. 275-282
Author(s):  
Samson Esayas ◽  
Dan Svantesson
Keyword(s):  
Court Decision ◽  
Final Report ◽  
Court Decisions ◽  
Clear Trend ◽  
Digital Platforms ◽  
Recent Developments ◽  
Selection Of

There is a clear trend of a hardening attitude towards digital platforms. In Australia this trend is exemplified by the Australian Competition and Consumer Commission’s current inquiry specifically into digital platforms. Further, it can also be seen in court decisions. Having discussed one such court decision, we give a brief overview of the Australian Competition and Consumer Commission’s digital platforms inquiry. We then seek to bring attention to a selection of particularly relevant European developments that may usefully inform how Australia proceeds in this arena and that may be considered in the Australian Competition and Consumer Commission’s final report due to be provided to the Treasurer on 3 June 2019.

scholarly journals A Review of Integrated On-Board EV Battery Chargers: Advanced Topologies, Recent Developments and Optimal Selection of FSCW Slot/Pole Combination

IEEE Access ◽  
2020 ◽  
Vol 8 ◽  
pp. 85216-85242 ◽  
Author(s):  
Mohamed Y. Metwly ◽  
Mahmoud S. Abdel-Majeed ◽  
Ayman S. Abdel-Khalik ◽  
Ragi A. Hamdy ◽  
Mostafa S. Hamad ◽  
...  
Keyword(s):  
Optimal Selection ◽  
Battery Chargers ◽  
Recent Developments ◽  
Selection Of

scholarly journals 324SPHINGOSINE-1-PHOSPHATE PROTECTS CULTURED BOVINE OOCYTES FROM PHYSIOLOGICALLY RELEVANT THERMAL STRESS

2004 ◽  
Vol 16 (2) ◽  
pp. 282 ◽  
Author(s):  
Z. Roth ◽  
P.J. Hansen
Keyword(s):  
Thermal Stress ◽  
Heat Shock ◽  
Blastocyst Stage ◽  
Caspase Activity ◽  
Blastocyst Development ◽  
Cleavage Rate ◽  
Developmental Potential ◽  
Oocyte Competence ◽  
Cell Death Pathway

Sphingosine-1-phosphate (S1P) is a sphingolipid metabolite that can block the sphingomyelin cell-death pathway by suppressing ceramide-induced apoptosis. The present study was performed to test whether S1P protects oocytes from heat shock during in vitro maturation. Cumulus-oocyte complexes obtained by slicing follicles were placed in maturation medium with or without 50nM S1P and cultured at 38.5°C (CON) or 41°C (41C) for the first 12h of maturation. Incubation during the last 10h of maturation (22-h total maturation time), fertilization, and embryonic development were performed at 38.5°C and 5% (v/v) CO2. Blastocyst development was recorded at 8 days post-insemination (dpi) and activity of group II caspases in 8-day blastocysts was determined using a fluoroprobe, PhiPhiLux-G1D2 (OncoImmunin, Gaithersburg, MD, USA). Data were analysed by least-squares ANOVA with the GLM procedure of SAS. Percentage data were subjected to arcsin transformation before analysis. Exposure of oocytes to thermal stress during the first 12h of maturation reduced cleavage rate (P<0.01) and the number of oocytes developing to the blastocyst stage (P<0.04). There was a temperature x S1P interaction for cleavage rate (P<0.03) because S1P blocked effects of thermal stress on cleavage rate. Without S1P, the percentage of oocytes that cleaved by 3 dpi were 83.6±2.7% and 65.8±2.7% for CON and 41C, respectively. In the presence of S1P, percent cleavage was 86.7±2.7% and 83.9±2.7% for CON and 41C, respectively. There was a trend (P=0.06) for a temperature x S1P interaction for percent oocytes developing to blastocyst stage because S1P blocked effects of heat shock on development. Without S1P, the percentages of oocytes that developed to the blastocyst stage were 28.7±3.0% and 15.2±3.0% for CON and 41C, respectively. In the presence of S1P, percent blastocysts were 24.3±3.4% and 23.9±3.0% for CON and 41C, respectively. When development was expressed as percentage of cleaved embryos, however, there were no effects of temperature, S1P, or temperature x S1P on percent development to the blastocyst stage. Blastocyst caspase activity was not affected by temperature or S1P. In summary, exposure to physiologically relevant thermal stress during the first 12h of maturation has a deleterious effect on oocyte competence and this effect can be reduced by S1P. The fact that heat shock reduced the percentage of oocytes but not the percentage of cleaved embryos that became blastocysts suggests that oocytes that survive effects of heat shock and cleave have normal potential to develop to the blastocyst stage. Moreover, since heat shock did not affect caspase activity, it is likely that blastocysts from heat-shocked oocytes have normal developmental potential, at least as determined by caspase activity. Support: BARD FI-330-2002 and USDA Grants 2002-35203-12664 and 2001-52101-11318.

scholarly journals Understanding Mental Health and Cognitive Restructuring With Ecological Neuroscience

2021 ◽  
Vol 12 ◽  
Author(s):  
James Crum
Keyword(s):  
Mental Health ◽  
Near Infrared ◽  
Ecological Validity ◽  
Experimental Designs ◽  
Functional Near Infrared Spectroscopy ◽  
Practical Applications ◽  
Recent Developments ◽  
The Brain ◽  
Neuroimaging Techniques ◽  
Selection Of

Neuroimaging and neuropsychological methods have contributed much toward an understanding of the information processing systems of the human brain in the last few decades, but to what extent do cognitive neuroscientific findings represent and generalize to the inter- and intra-brain dynamics engaged in adapting to naturalistic situations? If it is not marked, and experimental designs lack ecological validity, then this stands to potentially impact the practical applications of a paradigm. In no other domain is this more important to acknowledge than in human clinical neuroimaging research, wherein reduced ecological validity could mean a loss in clinical utility. One way to improve the generalizability and representativeness of findings is to adopt a more “real-world” approach to the development and selection of experimental designs and neuroimaging techniques to investigate the clinically-relevant phenomena of interest. For example, some relatively recent developments to neuroimaging techniques such as functional near-infrared spectroscopy (fNIRS) make it possible to create experimental designs using naturalistic tasks that would otherwise not be possible within the confines of a conventional laboratory. Mental health, cognitive interventions, and the present challenges to investigating the brain during treatment are discussed, as well as how the ecological use of fNIRS might be helpful in bridging the explanatory gaps to understanding the cultivation of mental health.

scholarly journals Progress in Starch-Based Materials for Food Packaging Applications

2022 ◽  
Vol 3 (1) ◽  
pp. 136-177
Author(s):  
Lucia García-Guzmán ◽  
Gustavo Cabrera-Barjas ◽  
Cintya G. Soria-Hernández ◽  
Johanna Castaño ◽  
Andrea Y. Guadarrama-Lezama ◽  
...  
Keyword(s):  
3D Printing ◽  
Chemical Modification ◽  
Shelf Life ◽  
Food Packaging ◽  
Environmentally Friendly ◽  
High Demand ◽  
Promising Alternative ◽  
Recent Developments ◽  
Single Use ◽  
Processing Techniques

The food packaging sector generates large volumes of plastic waste due to the high demand for packaged products with a short shelf-life. Biopolymers such as starch-based materials are a promising alternative to non-renewable resins, offering a sustainable and environmentally friendly food packaging alternative for single-use products. This article provides a chronology of the development of starch-based materials for food packaging. Particular emphasis is placed on the challenges faced in processing these materials using conventional processing techniques for thermoplastics and other emerging techniques such as electrospinning and 3D printing. The improvement of the performance of starch-based materials by blending with other biopolymers, use of micro- and nano-sized reinforcements, and chemical modification of starch is discussed. Finally, an overview of recent developments of these materials in smart food packaging is given.

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