Mammalian oocyte maturation chromosome in vitro oocyte maturation techniques. Medical search. Frequent questions

SECM technique may be a valuable tool for accurately assessing the quality of embryos and thereby contribute to improving outcomes associated with assisted reproduction, including human in vitro fertilization. (bioone.org)
These protease-induced decreases in IGFBP-4 and -5 likely cause increased levels of bioavailable (or free) IGFs that stimulate steroidogenesis and mitogenesis in developing dominant follicles, which ultimately prepare the follicle(s) and oocyte(s) for successful ovulation and fertilization. (bioone.org)
The present review discusses methods to improve oocyte quality in older women and new stimulation protocols that may improve the number of mature oocytes retrieved during an in vitro fertilization cycle. (arvigen.com)
Usage of melatonin during in vitro fertilization (IVF) procedures has been found to improve oocyte quality, survival, and fecundity. (jrhm.org)
Following germinal vesicle break down (GVBD) the oocyte is transcriptionally quiescent until fertilization and activation of the embryonic genome, occurring at the four-cell stage of development in the pig [ 9 ]. (biomedcentral.com)
Assisted reproductive techniques for canines: preservation of genetic material in domestic dogs [3] "Assisted reproductive techniques (ARTs), such as artificial insemination, in vitro fertilization, and cryopreservation of gametes/zygotes, have been developed to improve breeding and reproduction of livestock and for the treatment of human infertility. (edu.au)
To ascertain whether the Kunming (KM) mouse is an available model for age-related decline in female fertility in human or not, oocytes from young (6-8 weeks), middle-aged (9 months) and aged (12 months) female mice were compared with respect to number of oocytes, frequency of in-vitro maturation (IVM) and in-vitro fertilization (IVF), and meiotic chromosome segregation and alignment. (cambridge.org)
Components and OPTIONS FOR in vivo test: In vitro maturation and fertilization maturation and fertilization had been carried out as described [21] previously. (bioskinrevive.com)
11 Among women undergoing in vitro fertilization-embryo transfer in the United States, deliveries per oocyte retrieved decreased from 36.9 percent among women under the age of 35 years to 20.5 percent among women between the ages of 38 and 40 years and to 10.7 percent among women between the ages of 41 and 42 years. (ldysinger.com)
On the one hand, reactive oxygen species (ROS) are mandatory mediators for essential cellular functions including the function of germ cells (oocytes and spermatozoa) and thereby the fertilization process. (hindawi.com)
However, these techniques have to be carried out very carefully as they, if applied wrongly, bear risks of generating ROS damaging the germ cells and preventing fertilization. (hindawi.com)
This has been shown for intrauterine insemination (IUI), in vitro fertilization (IVF), and ICSI, and increased incidences of chromosomal abnormalities, minor and major birth defects, or early childhood cancers, particularly in the male offspring, have been linked to these procedures [ 8 - 16 ]. (hindawi.com)
Oocytes are highly specialized cells that undergo the unique processes of meiosis and fertilization and execute a molecular program for development [ 1 ]. (biomedcentral.com)
Hence, to date, an effective and simple proxy of oocyte quality parameters has not been established yet making difficult for an accurate assessment of the female gamete quality before fertilization. (biomedcentral.com)
In the oocyte, mitochondria play a central role in cellular metabolism providing energy for successful cytoplasm and nucleus maturation, fertilization, embryo development, calcium homeostasis, and apoptosis initiation. (biomedcentral.com)

At puberty the number of oocytes decreases even more to reach about 60,000 to 80,000 per ovary, and only about 500 mature oocytes will be produced during a woman's life, the others will undergo atresia(degeneration). (wikipedia.org)

This is a very important process in mammalian reproduction as hundreds of sperm reach the egg at the same time and dispermy would create an embryo with three haploid sets of chromosomes (triploidy) that would be extremely unlikely to survive. (pediagenosis.com)
The spermatozoon determines the sex of the embryo by producing either an XY (male) or XX (female) pair of sex chromosomes. (pediagenosis.com)
For in vivo test: In vitro lifestyle and embryo freezing After IVF, oocytes encircled with cumulus cells had been placed in fresh new TCM-199 moderate, as well as the embryos had been co-cultured with cumulus cells, as previously defined [21]. (bioskinrevive.com)

Oogenesis consists of several sub-processes: oocytogenesis, ootidogenesis, and finally maturation to form an ovum (oogenesis proper). (wikipedia.org)
Second Polar Body (Discarded afterward) + Ovum Oocyte meiosis, important to all animal life cycles yet unlike all other instances of animal cell division, occurs completely without the aid of spindle-coordinating centrosomes. (wikipedia.org)
Diagram showing the reduction in number of the chromosomes in the process of maturation of the ovum . (wikipedia.org)
With ovulation the secondary oocyte (or ovum) is expelled from the follicle on the ovary surface. (pediagenosis.com)

This study was conducted to evaluate in vivo and in vitro development of in vitro-matured equine oocytes fertilized by intracytoplasmic sperm injection. (bioone.org)

Some cells in some multicellular organisms lack mitochondria (for example, mature mammalian red blood cells ). (wikipedia.org)
In affected ovaries, oxygenation of follicular fluid is low, ultrastructural disturbances especially of mitochondria, occur in granulosa cells and oocytes, and considerable disturbances of meiosis occur. (biomedcentral.com)

It is developed from the primary oocyte by maturation. (wikipedia.org)
The succeeding phase of ootidogenesis occurs when the primary oocyte develops into an ootid. (wikipedia.org)

The Human Genome Project (HGP) was an international scientific effort to sequence the entire human genome, that is, to produce a map of the base pairs of DNA in the human chromosomes, most of which do not vary among individuals. (asu.edu)
Mammalian Genome 33, 590-605 (2022). (cuni.cz)
The mammalian genome comprises nuclear DNA (nDNA) derived from both parents and mitochondrial DNA (mtDNA) that is maternally inherited and encodes essential proteins required for oxidative phosphorylation. (regenerativemedicine.net)

Xenopus oocytes are encompassed by a layer of follicular cells that contribute to oocyte growth and meiosis in relation to oocyte maturation. (bvsalud.org)
Here, we investigated Xenopus follicular cell function using oocyte signaling and heterologous-expressing capabilities. (bvsalud.org)
Endogenous MeCP2 and MBD3 were precipitated from Xenopus oocyte extracts and conditions for methylation-specific binding were optimized. (biomedcentral.com)
an investigation of their specific localization in human brain and their influence on CaV2.1 voltage-dependent calcium channels expressed in Xenopus oocytes. (biomedcentral.com)
In addition, we investigated whether human γ 2 or γ 4 could modulate the electrophysiological properties of a neuronal VDCC complex transiently expressed in Xenopus oocytes. (biomedcentral.com)
When co-expressed in Xenopus oocytes with a Ca V 2.1/β 4 VDCC complex, either in the absence or presence of an α2δ 2 subunit, neither γ 2 nor γ 4 significantly modulated the VDCC peak current amplitude, voltage-dependence of activation or voltage-dependence of steady-state inactivation. (biomedcentral.com)

The spindle assembly checkpoint (SAC) is an intricate surveillance mechanism that ensures accurate segregation of chromosomes throughout cell cycles. (bvsalud.org)
Significant reduction of germinal vesicle (GV) and MII oocytes and significant increase of metaphase chromosome misalignment and premature chromatid segregation after meiotic maturation of oocytes, similar to human, presumably contribute to the decline in aged KM mice. (cambridge.org)
It mediates proper CHROMOSOME SEGREGATION and contractile ring function during CYTOKINESIS. (lookformedical.com)
Aurora kinases are found in all organisms in which their function has been conserved throughout evolution, namely the control of chromosome segregation. (lookformedical.com)

Oocytes were collected from slaughterhouse-derived ovaries, matured in vitro, and injected with frozen-thawed stallion sperm. (bioone.org)

The decreased quality of oocytes involves an increased rate of chromosomal aneuploidy with aging predominantly related to meiotic errors during oocyte maturation. (arvigen.com)
in 2015 showed that supplementation of CoQ10 in an aged animal model delayed decline in ovarian reserve, restored oocyte mitochondrial gene expression, and improved mitochondrial activity with a significant reduction in oocyte aneuploidy. (arvigen.com)
As atresia continues, both the number and quality of oocytes fall below a critical level, and the rate of aneuploidy increases - a finding that is related at least in part to problems of the meiotic spindle 15 , 16 resulting in nondisjunction. (ldysinger.com)
Gasic, S., Mihola, O. & Trachtulec, Z. Prdm9 deficiency of rat oocytes causes synapsis among non-homologous chromosomes and aneuploidy. (cuni.cz)

The granulosa cells produce a small molecule, cyclic GMP, that diffuses into the oocyte through the gap junctions. (wikipedia.org)
Because the granulosa cells and oocyte are connected by gap junctions, cyclic GMP also decreases in the oocyte, causing meiosis to resume. (wikipedia.org)

In addition, we determined that oocytes surrounded by their follicular cells expressing EGFR-Grb7 exhibit normal meiotic resumption. (bvsalud.org)
The oocyte must maintain arrest at the diplotene stage until meiotic resumption occurs. (biomedcentral.com)

The oocyte is surrounded by cumulus cells (also termed the corona radiata) from the follicle and spermatozoa must break through this outer layer to reach the oocyte itself (Figure 10.3). (pediagenosis.com)
Maturation of the mammalian oocyte is a complex process involving internal checkpoints and bidirectional communication with the surrounding cumulus cells. (biomedcentral.com)

As follicles grow, they acquire receptors for luteinizing hormone, a pituitary hormone that reinitiates meiosis in the oocyte and causes ovulation of a fertilizable egg. (wikipedia.org)

The secondary oocyte was paused partway through meiosis II (see Chapter 9). (pediagenosis.com)

We found that oocytes deprotected from their surrounding layer of follicular cells and expressing the epidermal growth factor (EGF) receptor (EGFR) and the Grb7 adaptor undergo accelerated prophase I to metaphase II meiosis progression upon stimulation by EGF. (bvsalud.org)
In this study, by whole-exome sequencing (WES), we identified homozygous and compound heterozygous MAD2L1BP variants in three families with female patients diagnosed with primary infertility owing to oocyte metaphase I (MI) arrest. (bvsalud.org)

Germinal vesicle breakdown (GVBD) occurs during oocyte meiotic maturation, a period when transcriptional processes are virtually inactive. (biomedcentral.com)
The mean number of ovarian follicles, ovarian germinal vesicle oocytes and ovulated MII oocytes decreased significantly with maternal age. (cambridge.org)

Oogonia enter meiosis during embryonic development, becoming oocytes. (wikipedia.org)
Understanding the biological functions of miRNAs in frozen maturated oocytes may provide a better understanding of embryonic development and a comparison of fertility conservation in female mammals. (bvsalud.org)

Mammalian oocytes are maintained in meiotic prophase arrest for a very long time-months in mice, years in humans. (wikipedia.org)
The endomitotic cycle (endomitosis) starts with a normal prophase (endoprophase), after which the chromosome contracts further (endometaphase), their sister chromatids separate from each other (endoanaphase) and decondense to assume the interphase nuclear structure, resulting in polyploid cells, with double the chromosome number (endopolyploidy) at the end of each cycle. (scielo.br)

Although assisted reproductive techniques (ART) have helped to solve many infertility problems, they cause changes in the expression of miRNA and genes in oocytes and preimplantation embryos, and the effect of these changes on the future of offspring is unknown, and has caused concerns. (bvsalud.org)
Therefore, in future, melatonin can be implicated as preferable therapeutic especially in IVF and assisted reproductive techniques. (jrhm.org)
In addition, other corrective measures include sperm separation for assisted reproductive techniques. (hindawi.com)

Maintenance of meiotic arrest also depends on the presence of a multilayered complex of cells, known as a follicle, that surrounds the oocyte. (wikipedia.org)
Removal of the oocyte from the follicle causes meiosis to progress in the oocyte. (wikipedia.org)

It has been hypothesized that in gonadal dysgenesis various deletions on the X chromosome cause such rapid atresia of oocytes 5 that few girls with this condition reach puberty with functioning ovaries. (ldysinger.com)
However, it is also possible that such genetic defects result in a smaller complement of oocytes during gonadal development. (ldysinger.com)

In principle it contains a diploid set of chromosomes. (pediagenosis.com)
With fertilisation the diploid number of chromosomes has been restored by combining chromosomes from the father and the mother. (pediagenosis.com)

The acrosomal cap of the head of the sperm breaks down, releasing enzymes that dissolve the zona pellucida locally allowing the spermatozoon to enter the oocyte (Figure 10.4). (pediagenosis.com)

cRNA microinjection of full-length or truncated MAD2L1BP uncovered their discordant roles in driving the extrusion of polar body 1 (PB1) in mouse oocytes. (bvsalud.org)
Furthermore, the patient's oocytes carrying the mutated MAD2L1BP resumed polar body extrusion (PBE) when rescued by microinjection of full-length MAD2L1BP cRNAs. (bvsalud.org)
The two cells that result from this division are the definitive oocyte and the second polar body. (pediagenosis.com)
The second polar body receives little cytoplasm, allowing the definitive oocyte to maintain its size. (pediagenosis.com)

The expression of miRNAs at the right time and place is crucial for the oocyte's maturation and the embryo's subsequent development. (bvsalud.org)
The spermatozoon will bring either an X or Y sex chromosome to the oocyte's X sex chromosome. (pediagenosis.com)

MicroRNAs (miRNAs) are small non-encoding RNAs that actively regulate biological and physiological processes, and play an important role in regulating gene expression in all cells, especially in most animal cells, including oocytes and embryos. (bvsalud.org)
In this paper, we describe a scanning electrochemical microscopy (SECM) technique that is a non-invasive and sensitive method for measuring oxygen consumption by individual embryos. (bioone.org)
The two enrichment strategies allow probing of methyl-CpG protein interactions in early vertebrate oocytes and embryos. (biomedcentral.com)

This unusual maturation unravels atypical spindle formation but is rescued by inhibiting integrin ß1 or Grb7 binding to the EGFR. (bvsalud.org)
These oocytes are protected from abnormal meiotic spindle formation through the recruitment of O-GlcNAcylated Grb7, and OGT (O-GlcNAc transferase), the enzyme responsible for O-GlcNAcylation processes, in the integrin ß1-EGFR complex. (bvsalud.org)
Furthermore, an O-GlcNAcylation increase (by inhibition of O-GlcNAcase), the glycosidase that removes O-GlcNAc moieties, or decrease (by inhibition of OGT) amplifies oocyte spindle defects when follicular cells are absent highlighting a control of the meiotic spindle by the OGT-O-GlcNAcase duo. (bvsalud.org)
Injection of myc-tagged JNK2α1 mRNA into oocytes also revealed its localization on spindle poles. (cambridge.org)
Works in various organisms have revealed that the kinase is involved in centrosome separation, duplication and maturation as well as in bipolar spindle assembly and stability. (lookformedical.com)

In 1913, as an undergraduate, Sturtevant created one of the earliest genetic maps of a fruit fly chromosome, which showed the relative positions of genes along the chromosome. (asu.edu)
1 , 2 The mechanism underlying this process is poorly understood and involves multiple factors encoded by genes on the X chromosome, as well as on autosomes. (ldysinger.com)
Despite considerable ongoing effort toward the identification of chromosome regions affected in autism and the characterization of many potential gene candidates, only a few genes have been reproducibly shown to display specific mutations that segregate with autism, likely because of the complex polygenic nature of this syndrome. (neurotransmitter.net)
Among those, several candidate genes have been shown to control the early patterning and/or the late synaptic maturation of specific neuronal subpopulations controlling the balance between excitation and inhibition in the developing cortex and cerebellum. (neurotransmitter.net)

Oogenesis starts with the process of developing primary oocytes, which occurs via the transformation of oogonia into primary oocytes, a process called oocytogenesis. (wikipedia.org)
Female infants have 6 to 7 million oocytes at 20 weeks of gestation, when progressive atresia occurs, resulting in 1 to 2 million oocytes at birth, approximately 25,000 at the age of 37 years, and 1000 at the age of 51 years, the average age of natural menopause in the United States. (ldysinger.com)

However, the effects of the interaction between follicular cells and the oocyte surface on meiotic processes are unclear. (bvsalud.org)
In summary, our study provides further insight into the role of the follicular cell layer in oocyte meiosis progression. (bvsalud.org)
The mammalian ovary has all the molecular machinery required for the biosynthesis of melatonin and interestingly concentration of melatonin in the follicular fluid of pre-ovulatory follicles is much higher than circulatory melatonin even in humans. (jrhm.org)
Further, melatonin and its receptors play a significant role in antioxidant defense mechanism of ovary for follicular growth and maturation. (jrhm.org)

Polytene chromosomes are structures found in highly specialized tissues in some animal and plant species, which are amplified through successive cycles of endoreduplication, finally producing several copies of each chromosome. (scielo.br)

As a result, these aged mice had more oocytes with stimulation, the developmental potential of the oocytes was improved, and more offspring were born compared to old animals receiving placebo 1. (arvigen.com)
Currently, its estimation is predominantly based on morphological analysis, which is subjective and does not consistently reflect the developmental competence of the oocytes. (biomedcentral.com)
however, it is not per se sufficient to assure oocyte developmental competence [ 13 ]. (biomedcentral.com)

However, as the oocyte grows, these proteins are synthesized, and meiotic arrest becomes dependent on cyclic AMP. (wikipedia.org)
In the oocyte, cyclic GMP prevents the breakdown of cyclic AMP by the phosphodiesterase PDE3, and thus maintains meiotic arrest. (wikipedia.org)
Human oocyte maturation arrest represents one of the severe conditions for female patients with primary infertility. (bvsalud.org)
Once the kinetochores of chromosomes are correctly attached to bipolar spindles and the SAC is satisfied, the MAD2L1BP, best known as p31comet, binds mitosis arrest deficient 2 (MAD2) and recruits the AAA+-ATPase TRIP13 to disassemble the mitotic checkpoint complex (MCC), leading to the cell-cycle progression. (bvsalud.org)
Together, our studies identified and characterized novel biallelic variants in MAD2L1BP responsible for human oocyte maturation arrest at MI, and thus prompted new therapeutic avenues for curing female primary infertility. (bvsalud.org)
Oocyte arrest at the diplotene stage is maintained in part through the activity of phosphodiesterase enzymes that catalyze the hydrolysis of cyclic adenosine monophosphate (cAMP) into AMP [ 1 , 2 ]. (biomedcentral.com)

This review focuses on the differential responses of cell types to ATZ toxicity, testicular effects of ATZ in both in vitro and in vivo models and chemopreventive strategies, so as to highlight the current state of the art on the toxicological outcomes of ATZ exposure in several experimental model systems. (frontiersin.org)
In vivo development was assessed after transfer of injected oocytes to the oviducts of recipient mares. (bioone.org)

As a follow-up study, conditional disruption of the gene PDSS-2, resulting in isolated CoQ deficiency in the oocytes of young animals, resulted in phenotypic changes characteristic of oocyte mitochondrial dysfunction associated with aging. (arvigen.com)
Thus, the maturing oocyte is reliant on processes such as post-transcriptional gene regulation (PTGR) to regulate the mRNA and protein repertoire. (biomedcentral.com)
The inability to transcribe mRNA during this stage of development and the probable necessity for post-transcriptional gene regulation (PTGR) suggests an important role for non-coding RNA in the maturing oocyte. (biomedcentral.com)
We are investigating how female lymphocytes maintain X-chromosome Inactivation, which is an epigenetic process responsible for equalizing gene expression between sexes. (upenn.edu)
The mouse Tzfp gene, mapped to chromosome 7 B2-B3, encodes a 465-amino acid transcription factor containing a conserved N-terminal BTB/POZ domain and three C-terminal PLZF-like C(2)H(2) zinc fingers. (lookformedical.com)
Nevertheless, the complexity of the techniques applied to assess gene expression and protein profile is a major bottleneck for the use of molecular markers in the oocyte quality assessment [ 12 ]. (biomedcentral.com)

It is well known that c-Jun N-terminal kinase (JNK) plays pivotal roles in various mitotic events, but its function in mammalian oocyte meiosis remains unknown. (cambridge.org)
Mammalian aurora-A belongs to a multigenic family of mitotic serine/threonine kinases comprising two other members: aurora-B and aurora-C. In this review we will focus on aurora-A that starts to localize to centrosomes only in S phase as soon as centrioles have been duplicated, the protein is then degraded in early G1. (lookformedical.com)
1985) described polytene chromosomes as giant chromosomes produced by changes in the mitotic cycle during the interphase stage. (scielo.br)

Our laboratory investigates X-chromosome Inactivation, and how this epigenetic process contributes to female-biased autoimmunity. (upenn.edu)

Several physiological parameters, such as viability, mitochondrial activity, and reactive oxygen species (ROS) levels have been also reported as useful markers of oocyte quality in marine invertebrates. (biomedcentral.com)

Inhibition of nuclear meiotic maturation via IBMX significantly increased MIR21 and decreased its target, PDCD4. (biomedcentral.com)

Atrazine (ATZ) is an environmental pollutant that interferes with several aspects of mammalian cellular processes including germ cell development, immunological, reproductive and neurological functions. (frontiersin.org)
Using in vitro and cellular techniques, we present a mVP40 assembly model highlighting two distinct oligomerization interfaces: the (N-terminal domain (NTD) and C-terminal domain (CTD)) in mVP40. (uci.edu)

Male European seabass, already predominant (~ 70%) in cultured stocks, show a high incidence (20-30%) of precocious sexual maturation under current aquaculture practices, leading to important economic losses for the industry. (biomedcentral.com)
In seabass aquaculture, the high incidence (20 to 30%) of precocious sexual maturation in males during the first year of life places a critical restraint to production parameters. (biomedcentral.com)

Despite several recent studies investigating molecular markers related to oocyte quality, methods currently available for their determination pose various technical challenges and limitations. (biomedcentral.com)

The multi-subunit shelterin complexes bind along mammalian telomeres, shielding the natural chromosome ends from engaging the DNA damage signaling and repair machinery [ 1 ]. (prolekarniky.cz)

To characterize the effect of artificially increasing MIR21 on oocyte competence without inhibiting GVBD, a MIR21 mimic, scrambled microRNA negative control, or nuclease free water was micro-injected into denuded oocytes at 21 h of IVM. (biomedcentral.com)

In the endoreduplication cycle, the chromatid number is duplicated, but they do not segregate, and after various endoreduplication cycles, larger and thicker chromosomes are produced, called polytenics. (scielo.br)

When in vitro experimental models are exposed to ATZ, they are faced with increased levels of reactive oxygen species (ROS), cytotoxicity and decreased growth rate at dosages that may vary with cell types. (frontiersin.org)
In view of the known modulation of reproductive development by swimming exercise in other teleost species, we aimed at investigating the effects of sustained swimming on reproductive development in seabass males during the first year of life in order to determine if swimming could potentially reduce precocious sexual maturation. (biomedcentral.com)
In plants, polytene chromosomes have been observed in only a few species, and seemed to be restricted to ovary and immature seed tissues, e.g., in Phaseolus coccineus and P. vulgaris (Nagl, 1981), until relatively recently, when they were observed in the cells of the anther tapetum of Vigna unguiculata (Guerra and Carvalheira, 1994) and of some Phaseolus species (Carvalheira and Guerra, 1994). (scielo.br)

The DNA condenses into chromosomes, and paternal and maternal chromosomes become aligned together on the equator of the cell. (pediagenosis.com)

Sister chromatids from each chromosome are pulled towards either end of the cell, as observed during anaphase in the mitosis chapter (see Figure 6.4). (pediagenosis.com)

It is commonly believed that, when oocytogenesis is complete, no additional primary oocytes are created, in contrast to the male process of spermatogenesis, where gametocytes are continuously created. (wikipedia.org)

A Feature Paper should be a substantial original Article that involves several techniques or approaches, provides an outlook for future research directions and describes possible research applications. (mdpi.com)

Decline in the Number of Oocytes from Birth to Menopause. (ldysinger.com)

X-chromosome Inactivation silences one X-chromosome in female cells, and this process is initiated and maintained by the long noncoding RNA Xist. (upenn.edu)
The progressive loss of oocytes from fetal life through menopause is a normal process. (ldysinger.com)

The adenylyl cyclase is kept active by a constitutively active G-protein-coupled receptor known as GPR3 and a G-protein, Gs, also present in the oocyte membrane. (wikipedia.org)

From one single oogonium, only one mature oocyte will rise, with 3 other cells called polar bodies. (wikipedia.org)
Matured oocytes had been inseminated with frozen-thawed semen from order MK-0822 a Japanese Dark bull (altered to 2 107 cells/ml) for 5 h at 38.5C within a humidified atmosphere with 5% CO2 in the surroundings, in 1 ml of BO solution containing 10 mg/ml bovine serum albumin and 10 g/ml heparin. (bioskinrevive.com)

The fact that live-birth rates from oocyte donation in older women are consistent with the age of the donor suggests that oocyte quality is the major factor responsible for reduced fecundability with aging. (arvigen.com)
Oocyte quality has been defined as the ability of oocytes to be fertilized and produce viable progeny. (biomedcentral.com)
Many investigations have been designed to gain new insights into the mechanisms underlying oocyte quality based on a differential analysis applied to molecular, biochemical, transcriptomic, or proteomic data. (biomedcentral.com)
Since recent clinical studies have indicated that dehydroepiandrosterone (DHEA) supplementation may reverse the problem of oocyte quality, this review of the literature was undertaken in an attempt to find an explanation of why this is effective? (biomedcentral.com)

However, in this group, the use of the available techniques is controversial and should be considered experimental. (ldysinger.com)

Anatomy17

Organisms4

Diseases1

Chemicals and Drugs10

Analytical, Diagnostic and Therapeutic Techniques and Equipment8

Phenomena and Processes18

Information Science3

Fertilization15

Mature oocytes1

Embryo3

Ovum4

Intracytoplasmic Sperm Inj1

Mitochondria2

Primary oocyte2

Genome3

Xenopus6

Segregation4

Injected with frozen-thawed1

Aneuploidy4

Granulosa cells2

Meiotic resumption2

Cumulus2

Ovulation1

Meiosis II1

Metaphase2

Germinal vesicle2

Embryonic development2

Prophase2

Reproductive techniques3

Follicle2

Gonadal2

Diploid2

Sperm1

Polar Body4

Oocyte's2

Embryos3

Spindle5

Genes4

Occurs2

Follicular4

Highly specialized1

Developmental3

Arrest6

Vivo2

Gene6

Mitotic3

Epigenetic1

Mitochondrial1

Nuclear1

Cellular2

Aquaculture2

Methods1

Complexes1

Competence1

Cycles1

Species3

Maternal1

Mitosis1

Oocytogenesis1

Involves1

Decline1

Process2

Protein1

Cells2

Quality4

Experimental1