scholarly journals Prediction of pregnancy after frozen-thawed embryo transfer via in vivo intrauterine oxidation-reduction potential measurements: a pilot study

2018 ◽  
Vol 17 (3) ◽  
pp. 255-261 ◽  
Author(s):  
Hitomi Nakamura ◽  
Takayoshi Hosono ◽  
Takeshi Taniguchi ◽  
Keiichi Kumasawa ◽  
Satoko Goa ◽  
...  
Keyword(s):  
Pilot Study ◽  
Embryo Transfer ◽  
Reduction Potential ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential ◽  
Frozen Thawed Embryo Transfer ◽  
Thawed Embryo Transfer

Apparatus and techniques for the measurement of oxidation-reduction potentials, pH and oxygen tension in vivo

1957 ◽  
Vol 146 (923) ◽  
pp. 289-297 ◽  
Keyword(s):  
Oxygen Tension ◽  
Reduction Potential ◽  
Model Experiments ◽  
Reduction Potentials ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential ◽  
Small Voltage

In order to follow the changes which occur in tumours during treatment with radiation, and the effects of radiosensitizing or radioprotecting drugs, apparatus and techniques have been developed to record automatically changes of oxidation-reduction potential on eight different electrodes. Simultaneous records of pH and oxygen tension changes were used as controls in some experiments. The changes of oxygen tension were followed by applying a known small voltage to one electrode and measuring the current which flowed. Calibration of oxygen-tension measurements was attempted by the use of model experiments.

Induced changes in oxidation-reduction potentials, pH, and oxygen tension in the intact lactating mammary gland

1957 ◽  
Vol 146 (924) ◽  
pp. 400-415 ◽  
Keyword(s):  
Growth Hormone ◽  
Mammary Gland ◽  
Oxygen Tension ◽  
Reduction Potential ◽  
Reduction Potentials ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential ◽  
Lactating Mammary Gland ◽  
Other Substances

This work was undertaken to find if a study of oxidation-reduction potentials, pH and oxygen tension would yield information concerning physiological changes induced in lactating mammary glands of rats and rabbits by hormones and other substances. Breathing oxygen at atmospheric pressure caused a rapid rise in oxygen tension in lactating mammary gland, and a small, slower rise of oxidation-reduction potential. Breathing nitrogen had the opposite effect. Oxytocin caused a rapid temporary fall of oxidation-reduction potential, synchronous with milk ejection. With adrenaline the response was more rapid and the oxygen tension fell to zero, to recover within 2 min. Vasopressin produced a slower fall and recovery. Insulin (35 μ g/kg) caused a preliminary rise of oxidation-reduction potential, followed by a fall lasting 1 h. The fall could be largely abolished by glucose. The synthetic oestrogen doisynolic acid caused a triphasic response in the oxidation-reduction potentials and increased oxygen tension in the gland. It reduced, but did not abolish, the changes due to insulin. Desoxycorticosterone glucoside caused a slow rise of oxidation-reduction potential, but did not alter the response to insulin. Intermedin caused a small rise of oxidation-reduction potential. The effects produced by commercial ACTH may have been due to the oxytocin and intermedin present. Growth hormone induced a small diphasic change in the oxidation-reduction potentials. The radiosensitizers tetrasodium 2-methyl-1:4-naphthohydroquinone diphosphate and tetrasodium trimethyl-hydroquinone diphosphate produced marked falls of oxidation-reduction potential even with small doses, without change of oxygen tension. Intravenous potassium ferricyanide appeared to liberate oxygen from haemoglobin in vivo . The pH of mammary gland became slightly more acid after breathing oxygen, and also in the preliminary response to insulin, glucose, doisynolic acid and desoxycorticosterone glucoside; and after oxytocin, vasopressin and growth hormone.

THE EFFECT OF ASSISTED HATCHING IN FROZEN-THAWED EMBRYO TRANSFER CYCLES

2016 ◽  
pp. 80-84
Author(s):  
Thi Tam An Nguyen ◽  
Minh Tam Le ◽  
Ngoc Thanh Cao
Keyword(s):  
Embryo Transfer ◽  
Zona Pellucida ◽  
Assisted Hatching ◽  
Implantation Failure ◽  
Multiple Pregnancies ◽  
Recurrent Implantation Failure ◽  
Key Words Laser ◽  
Implantation And Pregnancy Rates ◽  
Frozen Thawed Embryo Transfer ◽  
Thawed Embryo Transfer

Background: Laser assisted hatching technique based on the hypothesis to make an artificial hole on zona pellucida (ZP) that can help embryo hatching out of ZP easily. This technique has been shown to increase implantation and pregnancy rates in women of advanced age, in women with recurrent implantation failure and following the transfer of frozen–thawed embryos. This study described the outcome of frozen–thawed embryo transfers with laser assisted hatching (LAH), which is one of the safest method in nowadays. Purpose: To assess the effect of assisted hatching technique on the clinical outcomes in vitrified-warmed transfer cycles. Method: A total of 65 thawed-transfer cycles with 153 thawed-embryos undertaken within a 12-month period were analysed, Assisted hatching with laser zona thinning was performed with one-quarter of the zona pellucida circumference. The overall thawed-embryos (day 3) were kept in culture overnight. Patient were prepared the suitable endometrium and transferred embryos advantageously. Results: In which, having the rate of survival embryos were 143 occupying 94.3%, the percentage of grade 1 and 2 embryos occupied 55.9% and 29,3% respectively, and that were enrolled LAH before transfering of frozen–thawed embryos. The average transferred embryos were 2.4±0.8, The rate of implantation per transferred embryos and per transferred embryos cycles was 19.5% and 43.1% respectively. The rate of clinical pregnancies per embryo transfer cycles occupied 33.8% with percentage of early miscarriages (biochemical pregnancies and early clinical miscarriages) was 12.3%. The rate of ongoing pregnancies was 30.8% and multiple pregnancies was low just 12.3%. This result was equal or higher than other researchs in embryos transfer had or no LAH. Conclusion: LAH contributed to stable frozen–thawed embryos transfer effectiveness. Key words: Laser assisted hatching, frozen–thawed embryos transfer, zona pellucida (ZP)

scholarly journals In situ measurements of oxidation–reduction potential and hydrogen peroxide concentration as tools for revealing LPMO inactivation during enzymatic saccharification of cellulose

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Adnan Kadić ◽  
Anikó Várnai ◽  
Vincent G. H. Eijsink ◽  
Svein Jarle Horn ◽  
Gunnar Lidén
Keyword(s):  
Reduction Potential ◽  
Enzymatic Saccharification ◽  
The State ◽  
Enzyme Inactivation ◽  
Ex Situ ◽  
Process Economics ◽  
Complete Inactivation ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential

Abstract Background Biochemical conversion of lignocellulosic biomass to simple sugars at commercial scale is hampered by the high cost of saccharifying enzymes. Lytic polysaccharide monooxygenases (LPMOs) may hold the key to overcome economic barriers. Recent studies have shown that controlled activation of LPMOs by a continuous H2O2 supply can boost saccharification yields, while overdosing H2O2 may lead to enzyme inactivation and reduce overall sugar yields. While following LPMO action by ex situ analysis of LPMO products confirms enzyme inactivation, currently no preventive measures are available to intervene before complete inactivation. Results Here, we carried out enzymatic saccharification of the model cellulose Avicel with an LPMO-containing enzyme preparation (Cellic CTec3) and H2O2 feed at 1 L bioreactor scale and followed the oxidation–reduction potential and H2O2 concentration in situ with corresponding electrode probes. The rate of oxidation of the reductant as well as the estimation of the amount of H2O2 consumed by LPMOs indicate that, in addition to oxidative depolymerization of cellulose, LPMOs consume H2O2 in a futile non-catalytic cycle, and that inactivation of LPMOs happens gradually and starts long before the accumulation of LPMO-generated oxidative products comes to a halt. Conclusion Our results indicate that, in this model system, the collapse of the LPMO-catalyzed reaction may be predicted by the rate of oxidation of the reductant, the accumulation of H2O2 in the reactor or, indirectly, by a clear increase in the oxidation–reduction potential. Being able to monitor the state of the LPMO activity in situ may help maximizing the benefit of LPMO action during saccharification. Overcoming enzyme inactivation could allow improving overall saccharification yields beyond the state of the art while lowering LPMO and, potentially, cellulase loads, both of which would have beneficial consequences on process economics.

scholarly journals The Negative Impact of Varicocele on Basic Semen Parameters, Sperm Nuclear DNA Dispersion and Oxidation-Reduction Potential in Semen

2021 ◽  
Vol 18 (11) ◽  
pp. 5977
Author(s):  
Kamil Gill ◽  
Michal Kups ◽  
Patryk Harasny ◽  
Tomasz Machalowski ◽  
Marta Grabowska ◽  
...  
Keyword(s):  
Reduction Potential ◽  
Nuclear Dna ◽  
Study Groups ◽  
Semen Parameters ◽  
Sperm Dna Fragmentation ◽  
Control Groups ◽  
Infertile Men ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential ◽  
Sperm Dna

Since varicocele is so common in infertile men, this study intends to analyse the relationships between varicocele and conventional semen characteristics, sperm nuclear DNA dispersion and oxidation-reduction potential (ORP) in semen. Varicocele-positive and varicocele-negative infertile men (study groups) showed significantly lower standard sperm parameters and higher sperm DNA fragmentation (SDF) and ORP in semen than healthy volunteers and subjects with proven fertility (control groups). A lower proportion of low SDF levels (0–15% SDF) and higher incidence of high SDF levels (>30% SDF), as well as a higher prevalence of high ORP values (>1.37 mV/106 sperm/mL), were found in the study groups vs. the control groups. Moreover, infertile men had significantly lower odds ratios (ORs) for low SDF levels and significantly higher ORs for high SDF levels and high ORP. SDF and ORP were negatively correlated with sperm number, morphology, motility and vitality. Furthermore, a significant positive correlation was found between SDF and ORP. The obtained results suggest that disorders of spermatogenesis may occur in varicocele-related infertility. These abnormalities are manifested not only by reduced standard semen parameters but also by decreased sperm DNA integrity and simultaneously increased oxidative stress in semen.

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