Top PDF Factors affecting the outcome of human blastocyst vitrification

Factors affecting the outcome of human blastocyst vitrification

Factors affecting the outcome of human blastocyst vitrification

With the refinement of extended culture systems, it is becoming more reliable to obtain blastocysts in vitro [1]. Due their high implantation rates, it is becoming a com- mon practice to limit transfer to one or two blastocysts at a time. Therefore, surplus blastocysts require an efficient cryopreservation method [2,3]. Slow freezing was the main method of cryopreservation [4], but vitrification is now on the rise. Vitrification is the glass-like solidification of a solution at a low temperature without ice crystal for- mation, which is made possible by extreme elevation in viscosity during freezing. This can be achieved by increas- ing the freezing and warming rates and/or increasing the concentration of the cryoprotectants [5]. Unlike slow freezing, vitrification results in the total elimination of ice crystal formation, both within the cells being vitrified and outside the cells in the surrounding solution [6]. Although high concentrations of cryoprotectants can be
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Study of uveitis in children and factors affecting visual outcome.

Study of uveitis in children and factors affecting visual outcome.

This is to certify that Dr. A. Nandhini, MS. Post Graduate Student in Ophthalmology, Regional Institute of Ophthalmology, Government Ophthalmic Hospital, Madras Medical College, carried out this dissertation titled Study of Uveitis in Children and Factors Affecting Visual Outcome by herself under my guidance and direct supervision during the period of May 2004 to March 2007. This dissertation is submitted to Tamil Nadu Dr. MGR Medical University, Chennai in partial fulfillment of the award of MS Degree (Ophthalmology).
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A clinical study of the factors affecting the outcome of intestinal resection and anastomosis

A clinical study of the factors affecting the outcome of intestinal resection and anastomosis

This is to certify that the dissertation entitled “ A clinical study of the factors affecting the outcome of intestinal resection and anastomosis ” is a bonafide research work done by Dr. AJAY ABRAHAM, M.S. Postgraduate student in the Department of General Surgery, Tirunelveli Medical College & Hospital, Tirunelveli, under the guidance of Dr. ALEX ARTHUR EDWARDS M.S., Associate Professor, Department of Surgery, Tirunelveli Medical College & Hospital, Tirunelveli, in partial fulfilment of the requirements for the degree of M.S. in GENERAL SURGERY.
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Analysis of the Factors Affecting Outcome of Therapeutic Penetrating Keratoplasty

Analysis of the Factors Affecting Outcome of Therapeutic Penetrating Keratoplasty

Abstract- This prospective study aims to determine the Factors affecting outcome of Therapeutic Penetrating Keratoplasty and its role in the management of corneal diseases. Penetrating keratoplasty is the final therapeutic option in the management of refractory corneal disease after conventional medical therapy fails to prevent corneal perforation. (1)

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A study of predictors and factors affecting outcome in diabetic ketoacidosis patients

A study of predictors and factors affecting outcome in diabetic ketoacidosis patients

This is to certify that this dissertation work titled “ A STUDY OF PREDICTORS AND FACTORS AFFECTING OUTCOME IN DIABETIC KETOACIDOSIS ” of the candidate DR. SHAARON.S with registration Number 201511209 for the award of M.D in the branch of General Medicine. I personally verified the urkund.com website for the purpose of plagiarism Check. I found that the uploaded thesis file contains from introduction to conclusion pages and result shows 4% of plagiarism in the dissertation.

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Factors Affecting the Surgical Outcome of Primary Exotropia in Children

Factors Affecting the Surgical Outcome of Primary Exotropia in Children

Exotropia is a disorder of ocular alignment characterized by an outward deviation of the eyes. It is considered as a common condition affecting about 1% of all children under the age of 11 years [1]. Exotropia may be classified as primary or secondary. Primary exotropia can be intermittent or constant depending on clinical history and examination. Secondary exotropia, on the other hand, is either consecutive or sensory (paralytic) based on overcorrection of exotropia or fundus pathology respectively. The aim of surgical correction of primary exotropia is to straighten the eye and attain a degree of binocular single vision if possible. Intermittent exotropia is the most common form of childhood exotropia [2-3]. Some patients progress into constant exodeviation, while others remain stable or improve; however, the natural history of this disorder remains obscure [4-6]. Some Patients with intermittent exotropia tend to develop an exotropic drift following surgical correction over time [3].
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Maternal factors affecting reported infant sleep outcome

Maternal factors affecting reported infant sleep outcome

outcome has not previously been examined in an Australian sample. As reported above in the current study after controlling for the influence of other variables perceived past maternal overprotection explained 8% of the variance in infant sleep outcome. In contrast in an overseas study Morrell and Steele (2003) found that perceived past maternal overprotection was not a significant predictor of sleeping problems in 13 month old infants. Methodological differences between the two studies may account for the discrepancy in the findings. Morrell and Steele used logistic regression analysis and within each block used a stepwise procedure to extract the variable of most significance. The factors that comprised the second block included anxiety and depression (GHQ-28, Goldberg & Hillier, 1979) and perception of parenting received during childhood as measured by the Care and Overprotection scales of the PBI (Parker, 1979b). Of these variables only depression was a significant predictor of infant sleep problems. The stepwise procedure in logistic regression has been criticised because this method can be heavily influenced by random variation in the data, with variables being included or removed from the model on purely statistical grounds (Tabachnick & Fidell, 2007). If for instance, Care and Overprotection factors were strongly negatively correlated as found in the current study and as has been reported in other studies (Parker, 1979b, 1989, 1999), it is possible that the effect of each could have been diluted resulting in them being removed from the model.
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Maternal factors affecting outcome of induction of labour

Maternal factors affecting outcome of induction of labour

Mode of delivery in the study was vaginal in 56.4% and caesarean section in 43.6%. This was not statistically significant. There are many factors that led to this outcome like maternal age, parity, gestational age at which the women were induced, BMI, Bishop score, indication of induction and method of induction which were explained earlier. A recent study in 2016 showed that 63.5% had vaginal delivery and 36.5% had caesarean section following induction of labour. 18

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Factors affecting outcome of cochlear implant: an observational study

Factors affecting outcome of cochlear implant: an observational study

Methods: A hospital based retrospective observational study in which 51 patients who underwent cochlear implant surgery from July 2017 to January 2019 were evaluated at Dr. Babasaheb Ambedkar Memorial Hospital, Byculla, Mumbai using 3 parameters i.e. Revised CAP score (CAP), meaningful auditory integration scale (MAIS), speech intelligibility rating (SIR) at various intervals postoperatively and outcome was evaluated.

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All-inside meniscal repair surgery: factors affecting the outcome

All-inside meniscal repair surgery: factors affecting the outcome

The techniques employed for meniscal repair have also evolved in recent years. First-generation techniques for meniscal repair were based on Henning’s technique (first inside-out repair, 1980) [4], but the potential risk of neu- rovascular damage has been a major concern for this type of repair. Russell Warren [5] introduced an outside-in technique which aimed at reducing neurovascular compli- cations. In recent years, an all-inside technique has been introduced, which is widely used currently (Figs. 1, 2) [6]. It would be ideal to repair all meniscus injuries; how- ever, the failure rate has been found to be significantly high and the implant costs considerable, requiring careful con- sideration and selection of the patients. Some studies have reported success rates for meniscal repair to be up to 60–90 % depending on the region of meniscal repair [7– 10]. Meniscal repairs performed in conjunction with ACL reconstruction are generally thought to have a better healing rate than meniscal repair in knees with intact ACLs [7]. The objective of our study was to assess the outcome of meniscal repair surgery, focusing in particular on meniscal
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Factors affecting ultrarapid vitrification and cryopreservation of embryos

Factors affecting ultrarapid vitrification and cryopreservation of embryos

detrimental effect on subsequent in vitro or in vivo development. Vitrification of embryos of other mammalian species was not quite as spectacular as that reported by Kasai et al. (1990) for mouse morulae but may be improved with further refinement in techniques. McGinnis and Youngs (1990) were unable to vitrify sheep morulae and early blastocysts but 33% of blastocysts survived in vitro. Schiewe, Rail, Stuart and Wildt (1991) obtained 73% in vitro survival of sheep late morulae to blastocyst stage embryos. Smorag, Gajda and Vieczorek (1989) vitrified various developmental stages of the rabbit embryo and obtained 20%, 44% and 93% in vitro survival with 1-to 2-cell, 8- and 16- cell rabbit embryos respectively. Their findings suggest that lower developmental stages of the embryo are more vulnerable to vitrification than the later developmental stages. Kasai, Hamaguchi, Zhu, Sakurai and Machida (1991) successfully vitrified rabbit morulae, 86% survived in vitro, while 56% developed in vivo. Kobayashi, Nagashima, Yamakawa, Kato and Ogawa (1990) obtained similar results but their in vivo development was less at 18%. Kono, Suzuki and Tsunoda (1988) vitrified rat blastocysts with an in vivo development rate of 41%. Their in vitro survival rate cannot be accurately determined as only selected frozen-thawed embryos, that is 48 morphologically good embryos out of a total of 149 frozen-thawed, were tested for survival in vitro. All 48 embryos survived and developed to hatched blastocyst stage. With bovine embryos Massip, Van der Zwalmen, Schelfen and Ectors (1986) obtained in vitro survival rates of 43% and 54% after freezing by vitrification of late morulae and early blastocysts. No survival however was obtained when bovine blastocysts were vitrified. Dobrinsky, Hess, Duby and Robl (1991) also obtained similar survival rates of the order of 57% with vitrified bovine morulae. Work on the vitrification of mouse oocytes has been equally successful with high post-thaw fertilization rates and subsequent in vitro development to the blastocyst stage (Nakagata, 1989; Kono, Kwon and Nakahara, 1991; Shaw, Fuller, Bernard and Shaw, 1991). Cryopreserved mouse oocytes fertilized post-thaw have been transferred to surrogates and the percentage of live bom was 46% (Nakagata,
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The new Rapid-i carrier is an effective system for human embryo vitrification at both the blastocyst and cleavage stage

The new Rapid-i carrier is an effective system for human embryo vitrification at both the blastocyst and cleavage stage

Concerns have been raised regarding the safety of open vitrification carriers for the cryopreservation of re- productive cells [2,20-22,35]. Although, there have been no reported incidents of human reproductive tissue con- tamination during storage in liquid nitrogen tanks to date, there has been a movement toward the use of “closed” sealed systems for human gamete/embryo cryo- preservation. The long-standing argument for use of open systems has been that the benefit of higher cooling rates and ease of embryo loading/recovery far outweigh the theoretical risks of using such and open system. This former objection is rapidly becoming obsolete with accu- mulating pregnancy outcome data from closed vitrifica- tion carriers [6]. The current data set provides further evidence to suggest that a closed vitrification carrier can be used effectively for embryos at both early and late stages. Despite the far lower cooling and warming rates
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Human sperm vitrification: the state of the art

Human sperm vitrification: the state of the art

parameters such as volume, concentration, motility, and seminal plasma features. Furthermore, it is difficult to es- tablish a universal stereotyped model to serve different cryopreservation purposes at human clinic. Rozati et al. [81] reviewed the pitfalls of human sperm cryopreserva- tion, especially the sperm banking for cancer patients [81]. In fact, there was an effort to establish a universal vitrifi- cation method for almost all the samples including oocytes, primary cells, stem cells, and genetically modified cells. The method proposed low concentrations of cryoprotectants in- cluding 1.5 M propanediol and 0.5 M trehalose in industrial grade microcapillaries made of highly conductive fused sil- ica. It was demonstrated that this universal protocol achieved high recovery and viability rates after vitrification for human mammary epithelial cells, rat hepatocytes, tumor cells from pleural effusions, and multiple cancer cell lines [82]. Unfortunately, due to the different characteristics of spermatozoa from the cell types tested, this method would not likely be superior to the specialized sperm cryopreser- vation protocols that exist presently.
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Factors Affecting the Reduced Audit Quality Behavior

Factors Affecting the Reduced Audit Quality Behavior

Abstract:- This study aims to examine the factors that influence reduced audit quality behavior, will the time budget pressure, auditor personality type, organizational commitment, and professional commitment influence reduced audit quality behavior. Research data is primary data collected through survey with e-questionnaire technique using purposive sampling method. The data obtained from the answers to the questionnaire were analyzed using the SPSS method (Statistical Package for Social Science) version 24.0. The sample of this study is the auditor who works at The Big Four Public Accounting Firm in Jakarta, amounting to 45 people. The results showed that time budget pressure had no significant effect on reduced audit quality behavior, auditor personality type had significant and positive effect on reduced audit quality behavior, organizational commitment had a significant and negative effect on reduced audit quality behavior and professional commitment had no effect on reduced audit quality behavior. So, from testing the four hypotheses proposed, two hypotheses can be accepted and the other two rejected. Based on the results of this study, the behaviors that can reduced audit quality are auditor personality type that directly influence the auditor's tendency to be included in reduced audit quality behavior and lack of organizational commitment.
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Vitrification of human oocyte using cryoloop

Vitrification of human oocyte using cryoloop

So far the cryoloop has been used on human, mouse (13) and monkey (14) blastocysts with excellent survival rates. Mavrides et al. (15) demonstrated that the new cryoloop vitrification technique followed by ICSI produce good embryo formation results compared with slow freezing and could hold the future for effective bovine oocyte cryopreservation. Lieberman and Tucker (16) demonstrated that using the cryoloop or the hemi straw system which enabled the achievement of ultra rapid cooling rates, in combination with the mixture of ethylene glycol and DMSO as cryoprotectant agents for vitrification can effectively improve survival rates of human oocytes after warming. Cai et al. (17) recently showed that the cryoloop vitrification method in combination with 20% ethylene glycol and 20 % dimethylsulphoxide as cryoprotectant had the minimal adverse effects on the spindle configuration of rabbit oocytes and embryo development.
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Effects of blastocyst artificial collapse prior to vitrification on hatching and ‎survival rates and the expression of klf4 gene in mouse embryos

Effects of blastocyst artificial collapse prior to vitrification on hatching and ‎survival rates and the expression of klf4 gene in mouse embryos

Although the rate of blastocysts implantation of embryos is higher than previous stages but their survival rate is lower than them, which could be attributed to the completely filled blastocoel cavity with liquid and increased possibility of the formation of ice crystals. This liquid could prevent the penetration of cryoprotecting materials into the embryos. In this study, we reduced the volume of blastocoel before vitrification and compared survival rate and quality of in vitro embryos through klf4 gene expression with control group. In vitro mouse blastocysts were divided into three groups. In group 1, the blastocoel volume of blastocysts were reduced before vitrification and warming. In group 2, blastocysts were just vitrified and warmed and the blastocysts of group 3 (control group) were not undergone any specific treatment and were not vitrified. The expression of klf4 gene was assessed using real-time PCR technique. Data were statistically analyzed using one-way ANOVA and Duncan’s post hoc tests. Our results showed that blastocoel volume reduction before vitrification significantly increased the hatching rate of the blastocysts from the zona pellucida and klf4 gene expression compared to vitrified group. Blastocoel volume reduction before vitrification could be used as an efficient method for improving the rate of in vitro fertilization.
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Analysis of the Environmental Factors Affecting the Growth Traits of Iran-Black Sheep

Analysis of the Environmental Factors Affecting the Growth Traits of Iran-Black Sheep

III. RESULTS AND DISCUSSION The data were used in the present study belonging to Abbas Abad sheep breeding station that Iran-Black breed has been created over there. As shown in Fig. 1, there was not such a big variation for all traits among different years, however, it was significant. Two reasons are supposed for this result, first, a scientific selection program has not been applied and second, environmental factors significantly influence the traits.

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Fast Cryopreservation of the Mammalian Embryos in Different Developmental Stages by 0.25 mL Straws Vitrification with One Equilibration Step

Fast Cryopreservation of the Mammalian Embryos in Different Developmental Stages by 0.25 mL Straws Vitrification with One Equilibration Step

When the data were statistically analyzed there were no significant differences observed between the hatching rate of the embryos cultured after vitrification regardless of the media used (p>0.05). The results obtained after in vitro culturing the embryos in blastocyst, vitrified in 0.25 mL straws, with one equilibration step are presented in table 4.

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Factors Affecting the Pricing Decisions in the Tattoo Industry

Factors Affecting the Pricing Decisions in the Tattoo Industry

The tattoo industry is a relatively up and coming service industry which is creating great avenues for the youngsters to pursue a serious career in this area as any other artist. This paper has highlighted the factors which affect the pricing of the service based on variables. Entrepreneurs and potential tattoo studio owners can use this information to hire tattoo artists, plan the finances involved in owning a tattoo studio and deciding on pricing strategies to sustain their position in the competitive market further defining the target audience.
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Measuring the Presumption of Effective Temperature to Determine Human Comfort in Iraq

Measuring the Presumption of Effective Temperature to Determine Human Comfort in Iraq

stemming from the human need for energy to carry out thier activities and work. Although the effort varies from one person to another and the health, age, biological and climatic situation varies, However human need is maintained because food is the source of the body's energy. Metabolism is influenced by various factors such as effort, age, gender, health status, type of nutrients and their impact on the amount of energy produced within the body. For biological agents, in terms of temperature, there is an inverse relationship between them and metabolism, as the level of metabolism in the cold atmosphere is increased and is in hot atmosphere is decrease. 9
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