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Papers by Ahmed Gad

Journal of the American College of Cardiology, 2015

Background Acute ST elevation myocardial infarction (STEMI) with double coronary thrombosis is a ... more Background Acute ST elevation myocardial infarction (STEMI) with double coronary thrombosis is a rare entity. Little information is known about its clinical presentation and management, owing to the low incidence. Methods We searched the Medline and Web of Science databases from 1990 until August 2014 for all case reports/series and observational studies, which reported simultaneous double thrombosis at the time of the primary percutaneous coronary intervention (PCI). Summation of each individual variable, mean for linear variables and percentages of categorical variables were calculated in the final results. Results A total of 29 articles were retrieved yielding 56 patients. Patients were mainly males (88%) with a mean age of 59 years. The patients were mainly smokers (59%). Cardiogenic shock was the predominant presentation (41%). Simultaneous thrombosis of the left anterior descending and right coronary arteries was the commonest (50%). Primary PCI was the main treatment (91%) and an intra-aortic balloon was utilized in 38% of the cases. The in-hospital mortality was 5.4%. Conclusion: Double thrombosis STEMI presents with a high incidence of cardiogenic shock. Large studies are needed to address the proper management of this condition. Demographics Percentage Age, y mean (range) 59 (32-88) Male 88% Smoking 59% Diabetes Mellitus 25% Hypertension 50% Hyperlipidemia 21% Family history of CAD 18% Previous CAD 16% Previous MI 13% Previous PCI 11% Clinical Presentation Percentage Cardiogenic shock 41% Ventricular arrhythmia 25% Bradyarrhythmia 18% Pulmonary edema 11% Management Percentage PCI 91% Glycoprotein IIb/IIIa inhibitors 64% Intra-aortic balloon 38% Transvenous pacemaker 18% Thrombectomy 14% Systemic thrombolysis 7% Intracoronary thrombolysis 2% Outcomes Percentage New onset heart failure 18% In-hospital mortality 5.4% Recurrent MI 4% Bleeding 4% Oasis, The Online Abstract Submission System Leave OASIS Feedback Powered by OASIS, The Online Abstract Submission and Invitation System SM

Case Reports, 2014

Spinal tuberculosis (Pott&amp... more Spinal tuberculosis (Pott's disease) is one of the common extra-pulmonary presentations of tuberculosis. Spinal tuberculosis commonly presents with back pain, fever and night sweats. In this report, we present a case of spinal tuberculosis complicated by bilateral large psoas abscesses. The patient presented with bilateral flank pain and swellings rather than the classic presentation of back pain. The aim of this report is to draw the attention of physicians to this uncommon presentation of spinal tuberculosis, as an early recognition of such condition may expedite diagnosis and treatment, thereby preventing future complications of the disease.

Egyptian dental journal

Abstract: Aim: To determine the best enzymatic method for collagen extraction from the Egyptian N... more Abstract: Aim: To determine the best enzymatic method for collagen extraction from the Egyptian Nile Tilapia fish scales. Methodology: Fish scales were collected, cleaned and demineralized using HCl solution. Two different techniques for fish scale collagen extraction were conducted, heating scales at 121 ºC prior to extraction, or extraction at 4 ºC. Extraction at 4 ºC was performed using two different enzymes, pepsin and papain, with two different concentrations for each. Results: Heating of scales at 121 ºC resulted in denaturation of collagen. Pepsin enzyme with 1 wt. % concentration was more effective for collagen extraction compared to papain enzyme of equal or even higher concentration. The results of Sodium dodecyl sulfate- Polyacrylamide Gel Electrophoresis (SDS-PAGE) showed that extracted collagens were type I collagen composed of at least two different α-chains with the α chain composition of (α1)2 α2 and (β) component as well. Conclusion: Nile Tilapia scales can be used ...

World Applied Sciences …, 2009

The goal of this paper is to develop a matching technique for sonar and underwater images where i... more The goal of this paper is to develop a matching technique for sonar and underwater images where it is used for a range of applications including stereo vision, classification of sonar images, underwater image registration and mosaicing,..., etc. The paper presents a novel scheme to improve the performance of image matching algorithms using a combination of independent matching similarity metrics. A number of corner similarity metrics have been developed to facilitate matching, however, any individual metric has a limited effectiveness depending on the content of images to be registered and the different types of distortions that may be present. This paper explores combining corner similarity metrics to produce more effective measures for corner matching. In particular the combination of two similarity metrics is investigated using experiments on a number of images exhibiting different types of transformations and distortions. The results suggest that a linear combination of different similarity metrics may produce more accurate and robust assessments of corner similarity.

Journal of Tribology, 2006

Joining two tubes of different diameters has important concerns in many industries and engineerin... more Joining two tubes of different diameters has important concerns in many industries and engineering applications. An eccentric reducer is often used in such applications. Therefore, a simple and easy technique for manufacturing an eccentric reducer is of much importance. The simplest technique for producing the eccentric reducers is the tube nosing through eccentric conical dies. In this paper the finite element simulation is used to investigate the eccentric nosing of circular tubes through an eccentric conical die. Simulation is performed to investigate the plastic deformations of the deformed tube and all the possible modes of failure during the eccentric nosing process. Identification of unfavorable modes of failure in the tube nosing process lead to design modification guidelines, design of preform, and the die shape, for the eccentric nosing process. The results obtained confirmed that the modified design of the tube blank not only improves the quality of the nosed-tube product but also reduces nosing load and improves the limiting nosing ratio. Comparison with the experimental results shows that the nosing load and the modes of failure are successfully predicted by the finite element simulation. Also, a preform design for the tube blank that can produce an eccentric reducer with collar end that did not need a trimming process is introduced.

Journal of Tribology, 2009

Recently, herringbone-grooved journal bearings (HGJBs) have important applications in high-speed ... more Recently, herringbone-grooved journal bearings (HGJBs) have important applications in high-speed rotating machinery. The groove action in pumping the lubricating fluid inward generates supporting stiffness and improves the stability of the bearing when operating concentrically. Several researchers have investigated the static and dynamic characteristics of HGJBs and grooved thrust bearings. Most of these investigations were theoretical and concentrated on HGJBs with rectangular-profile grooves. In the present work, the static and dynamic characteristics of the beveled-step HGJBs are experimentally investigated. The bearing attitude angle, pressure distribution, and bearing friction torque were measured on a hydrodynamic lubrication unit, and then the static and dynamic characteristics were determined. The obtained experimental results are compared to the obtained experimental results for plain journal bearing. The merits as well as the demerits of the groove profile were discussed through comparisons with plain journal bearings.

Journal of the Chemical Society (Resumed), 1949

Animal Reproduction Science, 2014

2009 National Radio Science Conference, 2009

2015 5th International Conference on Information & Communication Technology and Accessibility (ICTA), 2015

One of the most important problems facing visual impaired people is money recognition especially ... more One of the most important problems facing visual impaired people is money recognition especially for paper currency. In this paper we present a simple system currency recognition system applied on Egyptian banknote. Our proposed system is based on simple image processing utilities that insure performing the process as fast and robust as possible. The basic techniques utilized in our proposed system include image foreground segmentation, histogram enhancement, region of interest (ROI) extraction and finally template matching based on the cross-correlation between the captured image and our data set. The experimental results demonstrate that the proposed method can recognize Egyptian paper money with high quality reaches 89% and short time.

2014 9th International Conference on Computer Engineering & Systems (ICCES), 2014

Human face is the most representative part of body that can be used to differentiate one person a... more Human face is the most representative part of body that can be used to differentiate one person among others. Accurate face identification system is still a challenge to Image Processing and Pattern Recognition researchers. In this paper, a complete framework for face-based personal identification system is proposed. The proposed frame work is composite of three basic stages; face skin detection FSD), facial features positioning (FFP), representative features extraction (RFE) and face matching (FM). For FSD stage, RGB-H-CbCr color model is used after a comparative study between different color models. Enhanced Haar-like features are utilized for FFP stage. After accurate features positioning, the representative features are calculated using the centers of eyes, nose and mouth organs. The experimental results of this paper depict that the proposed frame work accurately identify persons of The Center for Vital Longevity Face Database. The proposed system could Identify the correct person with 40 saved image with accuracy 98%, while it could reject wrong persons with accuracy 98.17%. The overall accuracy of correct identification reaches 98.14%.

Proceedings of Spie the International Society For Optical Engineering, 2002

The Interacting Multiple Model (IMM) estimator is a suboptimal hybrid filter that has been shown ... more The Interacting Multiple Model (IMM) estimator is a suboptimal hybrid filter that has been shown to be one of the most cost-effective hybrid state estimation schemes. The algorithm has the ability to estimate the state of a dynamic system with several modes which can switch from one mode to another. It is also considered to be the best compromise between the complexity and the performance. It is mainly used for tracking highly maneuvering targets in the presence of clutter by invoking the Probabilistic Data Association (PDA) in the estimator structure, also called IMM-PDA. Recently, it has been shown that the PDA technique does not perform well when tracking targets at low signal to noise ratios (SNR). An alternative technique to data association is the Fuzzy Data Association (FDA) which has the ability to track targets in clutter and in a low SNR environment. In this paper, an IMM-FDA technique is proposed for tracking highly maneuvering targets in clutter and in a low SNR environment. Simulations have been conducted to compare the performance of the proposed approach with that of the IMM-PDA. A typical scenario for a highly maneuvering target is considered as a tracking example. The simulation results reveal that both the trackers perform well when tracking the maneuvering target at high SNR. At low SNR, only the IMM-FDA is able to track the target accurately.

Reproduction, Fertility and Development, 2015

ABSTRACT Early embryonic development, the period from oocyte maturation until blastocyst formatio... more ABSTRACT Early embryonic development, the period from oocyte maturation until blastocyst formation, is the most critical period of mammalian development. It is well known that in vitro maturation, fertilization, and culture of bovine embryos is highly affected by culture conditions. However, the stage-specific effect of culture environment is poorly understood. Therefore, we aimed to examine the effect of in vitro culture conditions during oocyte maturation and fertilization on the transcriptome profile of the resulting blastocysts. Bovine oocytes were matured in vitro and then either directly transferred to synchronized recipients, fertilized, and cultured in vivo (Vitro_M), or transferred after in vitro fertilization (Vitro_F), or at zygote stage (Vitro_Z) and blastocysts were collected at Day 7 by uterine flushing. For in vivo or in vitro fertilization, the same frozen-thawed commercial bull semen has been used. Complete in vitro (IVP) and in vivo produced blastocysts were used as controls. Gene expression patterns between each blastocyst group and in vivo produced blastocyst group were compared using EmbryoGENE's bovine microarray (EmbryoGENE, Québec, QC, Canada) over six replicates of each group (10 blastocyst/replicate). Microarray data were statistically analysed using the Linear Models for Microarray Data Analysis (LIMMA) package under the R program (The R Project for Statistical Computing, Vienna, Austria). Results showed that, the longer the embryos spent under in vitro conditions, the higher was the number of differentially expressed genes (DEG, fold-change=2 with adjusted P-value=0.05) compared with in vivo control group. The Vitro_M group showed the lowest number of DEG (149); in contrast IVP group represented 841, DEG, respectively compared to in vivo control group. Ontological classification of DEG showed that lipid metabolism was the most significant function influenced by in vitro maturation conditions. More than 55% of DEG in the Vitro_M group were involved in the lipid metabolism process and most of them showed down-regulation compared to in vivo control group. On the other hand, Vitro_F and Vitro_Z groups showed nearly similar numbers of DEG (584 and 532, respectively) and the majority of these genes in both groups were involved in cell-death- and cell-cycle-related functions. Pathway analysis revealed that retinoic acid receptor activation pathways were the common ones in the Vitro_M and Vitro_F groups. However, different signalling pathways were commonly dominant in the Vitro_F and Vitro_Z groups. This study provides the transcriptome elasticity of bovine embryos exposed to different environments during maturation, fertilization, and culture periods of development.

PloS one, 2015

Early embryonic loss and altered gene expression in in vitro produced blastocysts are believed to... more Early embryonic loss and altered gene expression in in vitro produced blastocysts are believed to be partly caused by aberrant DNA methylation. However, specific embryonic stage which is sensitive to in vitro culture conditions to alter the DNA methylation profile of the resulting blastocysts remained unclear. Therefore, the aim of this study was to investigate the stage specific effect of in vitro culture environment on the DNA methylation response of the resulting blastocysts. For this, embryos cultured in vitro until zygote (ZY), 4-cell (4C) or 16-cell (16C) were transferred to recipients and the blastocysts were recovery at day 7 of the estrous cycle. Another embryo group was cultured in vitro until blastocyst stage (IVP). Genome-wide DNA methylation profiles of ZY, 4C, 16C and IVP blastocyst groups were then determined with reference to blastocysts developed completely under in vivo condition (VO) using EmbryoGENE DNA Methylation Array. To assess the contribution of methylation...

Journal of the American College of Cardiology, 2015

Background Acute ST elevation myocardial infarction (STEMI) with double coronary thrombosis is a ... more Background Acute ST elevation myocardial infarction (STEMI) with double coronary thrombosis is a rare entity. Little information is known about its clinical presentation and management, owing to the low incidence. Methods We searched the Medline and Web of Science databases from 1990 until August 2014 for all case reports/series and observational studies, which reported simultaneous double thrombosis at the time of the primary percutaneous coronary intervention (PCI). Summation of each individual variable, mean for linear variables and percentages of categorical variables were calculated in the final results. Results A total of 29 articles were retrieved yielding 56 patients. Patients were mainly males (88%) with a mean age of 59 years. The patients were mainly smokers (59%). Cardiogenic shock was the predominant presentation (41%). Simultaneous thrombosis of the left anterior descending and right coronary arteries was the commonest (50%). Primary PCI was the main treatment (91%) and an intra-aortic balloon was utilized in 38% of the cases. The in-hospital mortality was 5.4%. Conclusion: Double thrombosis STEMI presents with a high incidence of cardiogenic shock. Large studies are needed to address the proper management of this condition. Demographics Percentage Age, y mean (range) 59 (32-88) Male 88% Smoking 59% Diabetes Mellitus 25% Hypertension 50% Hyperlipidemia 21% Family history of CAD 18% Previous CAD 16% Previous MI 13% Previous PCI 11% Clinical Presentation Percentage Cardiogenic shock 41% Ventricular arrhythmia 25% Bradyarrhythmia 18% Pulmonary edema 11% Management Percentage PCI 91% Glycoprotein IIb/IIIa inhibitors 64% Intra-aortic balloon 38% Transvenous pacemaker 18% Thrombectomy 14% Systemic thrombolysis 7% Intracoronary thrombolysis 2% Outcomes Percentage New onset heart failure 18% In-hospital mortality 5.4% Recurrent MI 4% Bleeding 4% Oasis, The Online Abstract Submission System Leave OASIS Feedback Powered by OASIS, The Online Abstract Submission and Invitation System SM

Case Reports, 2014

Spinal tuberculosis (Pott&amp... more Spinal tuberculosis (Pott's disease) is one of the common extra-pulmonary presentations of tuberculosis. Spinal tuberculosis commonly presents with back pain, fever and night sweats. In this report, we present a case of spinal tuberculosis complicated by bilateral large psoas abscesses. The patient presented with bilateral flank pain and swellings rather than the classic presentation of back pain. The aim of this report is to draw the attention of physicians to this uncommon presentation of spinal tuberculosis, as an early recognition of such condition may expedite diagnosis and treatment, thereby preventing future complications of the disease.

Egyptian dental journal

Abstract: Aim: To determine the best enzymatic method for collagen extraction from the Egyptian N... more Abstract: Aim: To determine the best enzymatic method for collagen extraction from the Egyptian Nile Tilapia fish scales. Methodology: Fish scales were collected, cleaned and demineralized using HCl solution. Two different techniques for fish scale collagen extraction were conducted, heating scales at 121 ºC prior to extraction, or extraction at 4 ºC. Extraction at 4 ºC was performed using two different enzymes, pepsin and papain, with two different concentrations for each. Results: Heating of scales at 121 ºC resulted in denaturation of collagen. Pepsin enzyme with 1 wt. % concentration was more effective for collagen extraction compared to papain enzyme of equal or even higher concentration. The results of Sodium dodecyl sulfate- Polyacrylamide Gel Electrophoresis (SDS-PAGE) showed that extracted collagens were type I collagen composed of at least two different α-chains with the α chain composition of (α1)2 α2 and (β) component as well. Conclusion: Nile Tilapia scales can be used ...

World Applied Sciences …, 2009

The goal of this paper is to develop a matching technique for sonar and underwater images where i... more The goal of this paper is to develop a matching technique for sonar and underwater images where it is used for a range of applications including stereo vision, classification of sonar images, underwater image registration and mosaicing,..., etc. The paper presents a novel scheme to improve the performance of image matching algorithms using a combination of independent matching similarity metrics. A number of corner similarity metrics have been developed to facilitate matching, however, any individual metric has a limited effectiveness depending on the content of images to be registered and the different types of distortions that may be present. This paper explores combining corner similarity metrics to produce more effective measures for corner matching. In particular the combination of two similarity metrics is investigated using experiments on a number of images exhibiting different types of transformations and distortions. The results suggest that a linear combination of different similarity metrics may produce more accurate and robust assessments of corner similarity.

Journal of Tribology, 2006

Joining two tubes of different diameters has important concerns in many industries and engineerin... more Joining two tubes of different diameters has important concerns in many industries and engineering applications. An eccentric reducer is often used in such applications. Therefore, a simple and easy technique for manufacturing an eccentric reducer is of much importance. The simplest technique for producing the eccentric reducers is the tube nosing through eccentric conical dies. In this paper the finite element simulation is used to investigate the eccentric nosing of circular tubes through an eccentric conical die. Simulation is performed to investigate the plastic deformations of the deformed tube and all the possible modes of failure during the eccentric nosing process. Identification of unfavorable modes of failure in the tube nosing process lead to design modification guidelines, design of preform, and the die shape, for the eccentric nosing process. The results obtained confirmed that the modified design of the tube blank not only improves the quality of the nosed-tube product but also reduces nosing load and improves the limiting nosing ratio. Comparison with the experimental results shows that the nosing load and the modes of failure are successfully predicted by the finite element simulation. Also, a preform design for the tube blank that can produce an eccentric reducer with collar end that did not need a trimming process is introduced.

Journal of Tribology, 2009

Recently, herringbone-grooved journal bearings (HGJBs) have important applications in high-speed ... more Recently, herringbone-grooved journal bearings (HGJBs) have important applications in high-speed rotating machinery. The groove action in pumping the lubricating fluid inward generates supporting stiffness and improves the stability of the bearing when operating concentrically. Several researchers have investigated the static and dynamic characteristics of HGJBs and grooved thrust bearings. Most of these investigations were theoretical and concentrated on HGJBs with rectangular-profile grooves. In the present work, the static and dynamic characteristics of the beveled-step HGJBs are experimentally investigated. The bearing attitude angle, pressure distribution, and bearing friction torque were measured on a hydrodynamic lubrication unit, and then the static and dynamic characteristics were determined. The obtained experimental results are compared to the obtained experimental results for plain journal bearing. The merits as well as the demerits of the groove profile were discussed through comparisons with plain journal bearings.

Journal of the Chemical Society (Resumed), 1949

Animal Reproduction Science, 2014

2009 National Radio Science Conference, 2009

2015 5th International Conference on Information & Communication Technology and Accessibility (ICTA), 2015

One of the most important problems facing visual impaired people is money recognition especially ... more One of the most important problems facing visual impaired people is money recognition especially for paper currency. In this paper we present a simple system currency recognition system applied on Egyptian banknote. Our proposed system is based on simple image processing utilities that insure performing the process as fast and robust as possible. The basic techniques utilized in our proposed system include image foreground segmentation, histogram enhancement, region of interest (ROI) extraction and finally template matching based on the cross-correlation between the captured image and our data set. The experimental results demonstrate that the proposed method can recognize Egyptian paper money with high quality reaches 89% and short time.

2014 9th International Conference on Computer Engineering & Systems (ICCES), 2014

Human face is the most representative part of body that can be used to differentiate one person a... more Human face is the most representative part of body that can be used to differentiate one person among others. Accurate face identification system is still a challenge to Image Processing and Pattern Recognition researchers. In this paper, a complete framework for face-based personal identification system is proposed. The proposed frame work is composite of three basic stages; face skin detection FSD), facial features positioning (FFP), representative features extraction (RFE) and face matching (FM). For FSD stage, RGB-H-CbCr color model is used after a comparative study between different color models. Enhanced Haar-like features are utilized for FFP stage. After accurate features positioning, the representative features are calculated using the centers of eyes, nose and mouth organs. The experimental results of this paper depict that the proposed frame work accurately identify persons of The Center for Vital Longevity Face Database. The proposed system could Identify the correct person with 40 saved image with accuracy 98%, while it could reject wrong persons with accuracy 98.17%. The overall accuracy of correct identification reaches 98.14%.

Proceedings of Spie the International Society For Optical Engineering, 2002

The Interacting Multiple Model (IMM) estimator is a suboptimal hybrid filter that has been shown ... more The Interacting Multiple Model (IMM) estimator is a suboptimal hybrid filter that has been shown to be one of the most cost-effective hybrid state estimation schemes. The algorithm has the ability to estimate the state of a dynamic system with several modes which can switch from one mode to another. It is also considered to be the best compromise between the complexity and the performance. It is mainly used for tracking highly maneuvering targets in the presence of clutter by invoking the Probabilistic Data Association (PDA) in the estimator structure, also called IMM-PDA. Recently, it has been shown that the PDA technique does not perform well when tracking targets at low signal to noise ratios (SNR). An alternative technique to data association is the Fuzzy Data Association (FDA) which has the ability to track targets in clutter and in a low SNR environment. In this paper, an IMM-FDA technique is proposed for tracking highly maneuvering targets in clutter and in a low SNR environment. Simulations have been conducted to compare the performance of the proposed approach with that of the IMM-PDA. A typical scenario for a highly maneuvering target is considered as a tracking example. The simulation results reveal that both the trackers perform well when tracking the maneuvering target at high SNR. At low SNR, only the IMM-FDA is able to track the target accurately.

Reproduction, Fertility and Development, 2015

ABSTRACT Early embryonic development, the period from oocyte maturation until blastocyst formatio... more ABSTRACT Early embryonic development, the period from oocyte maturation until blastocyst formation, is the most critical period of mammalian development. It is well known that in vitro maturation, fertilization, and culture of bovine embryos is highly affected by culture conditions. However, the stage-specific effect of culture environment is poorly understood. Therefore, we aimed to examine the effect of in vitro culture conditions during oocyte maturation and fertilization on the transcriptome profile of the resulting blastocysts. Bovine oocytes were matured in vitro and then either directly transferred to synchronized recipients, fertilized, and cultured in vivo (Vitro_M), or transferred after in vitro fertilization (Vitro_F), or at zygote stage (Vitro_Z) and blastocysts were collected at Day 7 by uterine flushing. For in vivo or in vitro fertilization, the same frozen-thawed commercial bull semen has been used. Complete in vitro (IVP) and in vivo produced blastocysts were used as controls. Gene expression patterns between each blastocyst group and in vivo produced blastocyst group were compared using EmbryoGENE's bovine microarray (EmbryoGENE, Québec, QC, Canada) over six replicates of each group (10 blastocyst/replicate). Microarray data were statistically analysed using the Linear Models for Microarray Data Analysis (LIMMA) package under the R program (The R Project for Statistical Computing, Vienna, Austria). Results showed that, the longer the embryos spent under in vitro conditions, the higher was the number of differentially expressed genes (DEG, fold-change=2 with adjusted P-value=0.05) compared with in vivo control group. The Vitro_M group showed the lowest number of DEG (149); in contrast IVP group represented 841, DEG, respectively compared to in vivo control group. Ontological classification of DEG showed that lipid metabolism was the most significant function influenced by in vitro maturation conditions. More than 55% of DEG in the Vitro_M group were involved in the lipid metabolism process and most of them showed down-regulation compared to in vivo control group. On the other hand, Vitro_F and Vitro_Z groups showed nearly similar numbers of DEG (584 and 532, respectively) and the majority of these genes in both groups were involved in cell-death- and cell-cycle-related functions. Pathway analysis revealed that retinoic acid receptor activation pathways were the common ones in the Vitro_M and Vitro_F groups. However, different signalling pathways were commonly dominant in the Vitro_F and Vitro_Z groups. This study provides the transcriptome elasticity of bovine embryos exposed to different environments during maturation, fertilization, and culture periods of development.

PloS one, 2015

Early embryonic loss and altered gene expression in in vitro produced blastocysts are believed to... more Early embryonic loss and altered gene expression in in vitro produced blastocysts are believed to be partly caused by aberrant DNA methylation. However, specific embryonic stage which is sensitive to in vitro culture conditions to alter the DNA methylation profile of the resulting blastocysts remained unclear. Therefore, the aim of this study was to investigate the stage specific effect of in vitro culture environment on the DNA methylation response of the resulting blastocysts. For this, embryos cultured in vitro until zygote (ZY), 4-cell (4C) or 16-cell (16C) were transferred to recipients and the blastocysts were recovery at day 7 of the estrous cycle. Another embryo group was cultured in vitro until blastocyst stage (IVP). Genome-wide DNA methylation profiles of ZY, 4C, 16C and IVP blastocyst groups were then determined with reference to blastocysts developed completely under in vivo condition (VO) using EmbryoGENE DNA Methylation Array. To assess the contribution of methylation...