The Experts below are selected from a list of 680379 Experts worldwide ranked by ideXlab platform
David K Gardner - One of the best experts on this subject based on the ideXlab platform.
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the effects of chemical and Physical Factors on mammalian embryo culture and their importance for the practice of assisted human reproduction
Human Reproduction Update, 2016Co-Authors: Petra L Wale, David K GardnerAbstract:Although laboratory procedures, along with culture media formulations, have improved over the past two decades, the issue remains that human IVF is performed in vitro (literally 'in glass').Using PubMed, electronic searches were performed using keywords from a list of chemical and Physical Factors with no limits placed on time. Examples of keywords include oxygen, ammonium, volatile organics, temperature, pH, oil overlays and incubation volume/embryo density. Available clinical and scientific evidence surrounding Physical and chemical Factors have been assessed and presented here.Development of the embryo outside the body means that it is constantly exposed to stresses that it would not experience in vivo. Sources of stress on the human embryo include identified Factors such as pH and temperature shifts, exposure to atmospheric (20%) oxygen and the build-up of toxins in the media due to the static nature of culture. However, there are other sources of stress not typically considered, such as the act of pipetting itself, or the release of organic compounds from the very tissue culture ware upon which the embryo develops. Further, when more than one stress is present in the laboratory, there is evidence that negative synergies can result, culminating in significant trauma to the developing embryo. It is evident that embryos are sensitive to both chemical and Physical signals within their microenvironment, and that these Factors play a significant role in influencing development and events post transfer. From the viewpoint of assisted human reproduction, a major concern with chemical and Physical Factors lies in their adverse effects on the viability of embryos, and their long-term effects on the fetus, even as a result of a relatively brief exposure. This review presents data on the adverse effects of chemical and Physical Factors on mammalian embryos and the importance of identifying, and thereby minimizing, them in the practice of human IVF. Hence, optimizing the in vitro environment involves far more than improving culture media formulations.
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the effects of chemical and Physical Factors on mammalian embryo culture and their importance for the practice of assisted human reproduction
Human Reproduction Update, 2016Co-Authors: Petra L Wale, David K GardnerAbstract:Background Although laboratory procedures, along with culture media formulations, have improved over the past two decades, the issue remains that human IVF is performed in vitro (literally 'in glass'). Methods Using PubMed, electronic searches were performed using keywords from a list of chemical and Physical Factors with no limits placed on time. Examples of keywords include oxygen, ammonium, volatile organics, temperature, pH, oil overlays and incubation volume/embryo density. Available clinical and scientific evidence surrounding Physical and chemical Factors have been assessed and presented here. Results and conclusions Development of the embryo outside the body means that it is constantly exposed to stresses that it would not experience in vivo. Sources of stress on the human embryo include identified Factors such as pH and temperature shifts, exposure to atmospheric (20%) oxygen and the build-up of toxins in the media due to the static nature of culture. However, there are other sources of stress not typically considered, such as the act of pipetting itself, or the release of organic compounds from the very tissue culture ware upon which the embryo develops. Further, when more than one stress is present in the laboratory, there is evidence that negative synergies can result, culminating in significant trauma to the developing embryo. It is evident that embryos are sensitive to both chemical and Physical signals within their microenvironment, and that these Factors play a significant role in influencing development and events post transfer. From the viewpoint of assisted human reproduction, a major concern with chemical and Physical Factors lies in their adverse effects on the viability of embryos, and their long-term effects on the fetus, even as a result of a relatively brief exposure. This review presents data on the adverse effects of chemical and Physical Factors on mammalian embryos and the importance of identifying, and thereby minimizing, them in the practice of human IVF. Hence, optimizing the in vitro environment involves far more than improving culture media formulations.
Petra L Wale - One of the best experts on this subject based on the ideXlab platform.
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the effects of chemical and Physical Factors on mammalian embryo culture and their importance for the practice of assisted human reproduction
Human Reproduction Update, 2016Co-Authors: Petra L Wale, David K GardnerAbstract:Although laboratory procedures, along with culture media formulations, have improved over the past two decades, the issue remains that human IVF is performed in vitro (literally 'in glass').Using PubMed, electronic searches were performed using keywords from a list of chemical and Physical Factors with no limits placed on time. Examples of keywords include oxygen, ammonium, volatile organics, temperature, pH, oil overlays and incubation volume/embryo density. Available clinical and scientific evidence surrounding Physical and chemical Factors have been assessed and presented here.Development of the embryo outside the body means that it is constantly exposed to stresses that it would not experience in vivo. Sources of stress on the human embryo include identified Factors such as pH and temperature shifts, exposure to atmospheric (20%) oxygen and the build-up of toxins in the media due to the static nature of culture. However, there are other sources of stress not typically considered, such as the act of pipetting itself, or the release of organic compounds from the very tissue culture ware upon which the embryo develops. Further, when more than one stress is present in the laboratory, there is evidence that negative synergies can result, culminating in significant trauma to the developing embryo. It is evident that embryos are sensitive to both chemical and Physical signals within their microenvironment, and that these Factors play a significant role in influencing development and events post transfer. From the viewpoint of assisted human reproduction, a major concern with chemical and Physical Factors lies in their adverse effects on the viability of embryos, and their long-term effects on the fetus, even as a result of a relatively brief exposure. This review presents data on the adverse effects of chemical and Physical Factors on mammalian embryos and the importance of identifying, and thereby minimizing, them in the practice of human IVF. Hence, optimizing the in vitro environment involves far more than improving culture media formulations.
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the effects of chemical and Physical Factors on mammalian embryo culture and their importance for the practice of assisted human reproduction
Human Reproduction Update, 2016Co-Authors: Petra L Wale, David K GardnerAbstract:Background Although laboratory procedures, along with culture media formulations, have improved over the past two decades, the issue remains that human IVF is performed in vitro (literally 'in glass'). Methods Using PubMed, electronic searches were performed using keywords from a list of chemical and Physical Factors with no limits placed on time. Examples of keywords include oxygen, ammonium, volatile organics, temperature, pH, oil overlays and incubation volume/embryo density. Available clinical and scientific evidence surrounding Physical and chemical Factors have been assessed and presented here. Results and conclusions Development of the embryo outside the body means that it is constantly exposed to stresses that it would not experience in vivo. Sources of stress on the human embryo include identified Factors such as pH and temperature shifts, exposure to atmospheric (20%) oxygen and the build-up of toxins in the media due to the static nature of culture. However, there are other sources of stress not typically considered, such as the act of pipetting itself, or the release of organic compounds from the very tissue culture ware upon which the embryo develops. Further, when more than one stress is present in the laboratory, there is evidence that negative synergies can result, culminating in significant trauma to the developing embryo. It is evident that embryos are sensitive to both chemical and Physical signals within their microenvironment, and that these Factors play a significant role in influencing development and events post transfer. From the viewpoint of assisted human reproduction, a major concern with chemical and Physical Factors lies in their adverse effects on the viability of embryos, and their long-term effects on the fetus, even as a result of a relatively brief exposure. This review presents data on the adverse effects of chemical and Physical Factors on mammalian embryos and the importance of identifying, and thereby minimizing, them in the practice of human IVF. Hence, optimizing the in vitro environment involves far more than improving culture media formulations.
Abu Bakar Salleh - One of the best experts on this subject based on the ideXlab platform.
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Physical Factors affecting the production of organic solvent tolerant protease by pseudomonas aeruginosa strain k
Bioresource Technology, 2005Co-Authors: Raja Noor Zaliha Raja Abd Rahman, Lee Poh Geok, Mahiran Basri, Abu Bakar SallehAbstract:Abstract The Physical Factors affecting the production of an organic solvent-tolerant protease from Pseudomonas aeruginosa strain K was investigated. Growth and protease production were detected from 37 to 45 °C with 37 °C being the optimum temperature for P. aeruginosa. Maximum enzyme activity was achieved at static conditions with 4.0% (v/v) inoculum. Shifting the culture from stationary to shaking condition decreased the protease production (6.0–10.0% v/v). Extracellular organic solvent-tolerant protease was detected over a broad pH range from 6.0 to 9.0. However, the highest yield of protease was observed at pH 7.0. Neutral media increased the protease production compared to acidic or alkaline media
Jorge E Chavarro - One of the best experts on this subject based on the ideXlab platform.
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work schedule and Physical Factors in relation to fecundity in nurses
Occupational and Environmental Medicine, 2015Co-Authors: Audrey J Gaskins, Janet W Richedwards, Christina C Lawson, Eva S Schernhammer, Stacey A Missmer, Jorge E ChavarroAbstract:Objectives To evaluate the association of work schedule and Physical Factors with fecundity. Methods Women currently employed outside the home and trying to get pregnant (n=1739) in the Nurses’ Health Study 3 cohort (2010–2014) were included in this analysis. Work schedule and Physical labour were self-reported on the baseline questionnaire, and every 6 months thereafter the women reported the duration of their ongoing pregnancy attempt. Multivariable accelerated failure time models were used to estimate time ratios (TR) and 95% CIs. Results Among the 1739 women (median age=33 years, 93% Caucasian) the estimated proportions of women not pregnant after 12 and 24 months were 16% and 5%, respectively. None of the various shift work patterns were associated with duration of pregnancy attempt (as a surrogate for fecundity). However, women working >40 h/week had a 20% (95% CI 7 to 35%) longer median duration of pregnancy attempt compared to women working 21–40 h/week (p-trend=0.005). Women whose work entailed heavy lifting or moving (ie, 25+ pounds) >15 times/day also had a longer median duration of pregnancy attempt (adjusted TR=1.49; 95% CI 1.20 to 1.85) compared to women who never lifted or moved heavy loads (p-trend=0.002). The association between heavy moving and lifting and duration of pregnancy attempt was more pronounced among overweight or obese women (body mass index, BMI Conclusions Working greater than 40 h per week and greater frequency of lifting or moving a heavy load were associated with reduced fecundity in a cohort of nurses planning pregnancy.
Raja Noor Zaliha Raja Abd Rahman - One of the best experts on this subject based on the ideXlab platform.
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Physical Factors affecting the production of organic solvent tolerant protease by pseudomonas aeruginosa strain k
Bioresource Technology, 2005Co-Authors: Raja Noor Zaliha Raja Abd Rahman, Lee Poh Geok, Mahiran Basri, Abu Bakar SallehAbstract:Abstract The Physical Factors affecting the production of an organic solvent-tolerant protease from Pseudomonas aeruginosa strain K was investigated. Growth and protease production were detected from 37 to 45 °C with 37 °C being the optimum temperature for P. aeruginosa. Maximum enzyme activity was achieved at static conditions with 4.0% (v/v) inoculum. Shifting the culture from stationary to shaking condition decreased the protease production (6.0–10.0% v/v). Extracellular organic solvent-tolerant protease was detected over a broad pH range from 6.0 to 9.0. However, the highest yield of protease was observed at pH 7.0. Neutral media increased the protease production compared to acidic or alkaline media
