Oocytes. Medical search

Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).

The process of germ cell development in the female from the primordial germ cells through OOGONIA to the mature haploid ova (OVUM).

Transfer of preovulatory oocytes from donor to a suitable host. Oocytes are collected, fertilized in vitro, and transferred to a host that can be human or animal.

Procedures to obtain viable OOCYTES from the host. Oocytes most often are collected by needle aspiration from OVARIAN FOLLICLES before OVULATION.

The commonest and widest ranging species of the clawed "frog" (Xenopus) in Africa. This species is used extensively in research. There is now a significant population in California derived from escaped laboratory animals.

A type of CELL NUCLEUS division, occurring during maturation of the GERM CELLS. Two successive cell nucleus divisions following a single chromosome duplication (S PHASE) result in daughter cells with half the number of CHROMOSOMES as the parent cells.

Methods used to induce premature oocytes, that are maintained in tissue culture, to progress through developmental stages including to a stage that is competent to undergo FERTILIZATION.

An aquatic genus of the family, Pipidae, occurring in Africa and distinguished by having black horny claws on three inner hind toes.

The injection of very small amounts of fluid, often with the aid of a microscope and microsyringes.

The fusion of a spermatozoon (SPERMATOZOA) with an OVUM thus resulting in the formation of a ZYGOTE.

The phase of cell nucleus division following PROMETAPHASE, in which the CHROMOSOMES line up across the equatorial plane of the SPINDLE APPARATUS prior to separation.

The granulosa cells of the cumulus oophorus which surround the OVUM in the GRAAFIAN FOLLICLE. At OVULATION they are extruded with OVUM.

A unisexual reproduction without the fusion of a male and a female gamete (FERTILIZATION). In parthenogenesis, an individual is formed from an unfertilized OVUM that did not complete MEIOSIS. Parthenogenesis occurs in nature and can be artificially induced.

A post-MORULA preimplantation mammalian embryo that develops from a 32-cell stage into a fluid-filled hollow ball of over a hundred cells. A blastocyst has two distinctive tissues. The outer layer of trophoblasts gives rise to extra-embryonic tissues. The inner cell mass gives rise to the embryonic disc and eventual embryo proper.

A mature haploid female germ cell extruded from the OVARY at OVULATION.

Interactive processes between the oocyte (OVUM) and the sperm (SPERMATOZOA) including sperm adhesion, ACROSOME REACTION, sperm penetration of the ZONA PELLUCIDA, and events leading to FERTILIZATION.

Preservation of cells, tissues, organs, or embryos by freezing. In histological preparations, cryopreservation or cryofixation is used to maintain the existing form, structure, and chemical composition of all the constituent elements of the specimens.

The reproductive organ (GONADS) in female animals. In vertebrates, the ovary contains two functional parts: the OVARIAN FOLLICLE for the production of female germ cells (OOGENESIS); and the endocrine cells (GRANULOSA CELLS; THECA CELLS; and LUTEAL CELLS) for the production of ESTROGENS and PROGESTERONE.

An assisted fertilization technique consisting of the microinjection of a single viable sperm into an extracted ovum. It is used principally to overcome low sperm count, low sperm motility, inability of sperm to penetrate the egg, or other conditions related to male infertility (INFERTILITY, MALE).

Morphological and physiological development of EMBRYOS.

The transfer of mammalian embryos from an in vivo or in vitro environment to a suitable host to improve pregnancy or gestational outcome in human or animal. In human fertility treatment programs, preimplantation embryos ranging from the 4-cell stage to the blastocyst stage are transferred to the uterine cavity between 3-5 days after FERTILIZATION IN VITRO.

A tough transparent membrane surrounding the OVUM. It is penetrated by the sperm during FERTILIZATION.

Protein kinase that drives both the mitotic and meiotic cycles in all eukaryotic organisms. In meiosis it induces immature oocytes to undergo meiotic maturation. In mitosis it has a role in the G2/M phase transition. Once activated by CYCLINS; MPF directly phosphorylates some of the proteins involved in nuclear envelope breakdown, chromosome condensation, spindle assembly, and the degradation of cyclins. The catalytic subunit of MPF is PROTEIN P34CDC2.

Mature male germ cells derived from SPERMATIDS. As spermatids move toward the lumen of the SEMINIFEROUS TUBULES, they undergo extensive structural changes including the loss of cytoplasm, condensation of CHROMATIN into the SPERM HEAD, formation of the ACROSOME cap, the SPERM MIDPIECE and the SPERM TAIL that provides motility.

The fertilized OVUM resulting from the fusion of a male and a female gamete.

The earliest developmental stage of a fertilized ovum (ZYGOTE) during which there are several mitotic divisions within the ZONA PELLUCIDA. Each cleavage or segmentation yields two BLASTOMERES of about half size of the parent cell. This cleavage stage generally covers the period up to 16-cell MORULA.

The technique of maintaining or growing mammalian EMBRYOS in vitro. This method offers an opportunity to observe EMBRYONIC DEVELOPMENT; METABOLISM; and susceptibility to TERATOGENS.

Synthetic transcripts of a specific DNA molecule or fragment, made by an in vitro transcription system. This cRNA can be labeled with radioactive uracil and then used as a probe. (King & Stansfield, A Dictionary of Genetics, 4th ed)

The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.

Proteins which are found in eggs (OVA) from any species.

Methods of implanting a CELL NUCLEUS from a donor cell into an enucleated acceptor cell.

The fluid surrounding the OVUM and GRANULOSA CELLS in the Graafian follicle (OVARIAN FOLLICLE). The follicular fluid contains sex steroids, glycoprotein hormones, plasma proteins, mucopolysaccharides, and enzymes.

Techniques for the artifical induction of ovulation, the rupture of the follicle and release of the ovum.

The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)

Cellular proteins encoded by the c-mos genes (GENES, MOS). They function in the cell cycle to maintain MATURATION PROMOTING FACTOR in the active state and have protein-serine/threonine kinase activity. Oncogenic transformation can take place when c-mos proteins are expressed at the wrong time.

Substances that provide protection against the harmful effects of freezing temperatures.

The transformation of a liquid to a glassy solid i.e., without the formation of crystals during the cooling process.

Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)

Minute cells produced during development of an OOCYTE as it undergoes MEIOSIS. A polar body contains one of the nuclei derived from the first or second meiotic CELL DIVISION. Polar bodies have practically no CYTOPLASM. They are eventually discarded by the oocyte. (from King & Stansfield, A Dictionary of Genetics, 4th ed)

The entity of a developing mammal (MAMMALS), generally from the cleavage of a ZYGOTE to the end of embryonic differentiation of basic structures. For the human embryo, this represents the first two months of intrauterine development preceding the stages of the FETUS.

RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.

Morphological and physiological development of EMBRYOS or FETUSES.

The ratio of the number of conceptions (CONCEPTION) including LIVE BIRTH; STILLBIRTH; and fetal losses, to the mean number of females of reproductive age in a population during a set time period.

Diminished or absent ability of a female to achieve conception.

A gonadotropic glycoprotein hormone produced primarily by the PLACENTA. Similar to the pituitary LUTEINIZING HORMONE in structure and function, chorionic gonadotropin is involved in maintaining the CORPUS LUTEUM during pregnancy. CG consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is virtually identical to the alpha subunits of the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity (CHORIONIC GONADOTROPIN, BETA SUBUNIT, HUMAN).

Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.

The discharge of an OVUM from a rupturing follicle in the OVARY.

Supporting cells for the developing female gamete in the OVARY. They are derived from the coelomic epithelial cells of the gonadal ridge. Granulosa cells form a single layer around the OOCYTE in the primordial ovarian follicle and advance to form a multilayered cumulus oophorus surrounding the OVUM in the Graafian follicle. The major functions of granulosa cells include the production of steroids and LH receptors (RECEPTORS, LH).

Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.

Proteins obtained from various species of Xenopus. Included here are proteins from the African clawed frog (XENOPUS LAEVIS). Many of these proteins have been the subject of scientific investigations in the area of MORPHOGENESIS and development.

Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.

An early embryo that is a compact mass of about 16 BLASTOMERES. It resembles a cluster of mulberries with two types of cells, outer cells and inner cells. Morula is the stage before BLASTULA in non-mammalian animals or a BLASTOCYST in mammals.

The major progestational steroid that is secreted primarily by the CORPUS LUTEUM and the PLACENTA. Progesterone acts on the UTERUS, the MAMMARY GLANDS and the BRAIN. It is required in EMBRYO IMPLANTATION; PREGNANCY maintenance, and the development of mammary tissue for MILK production. Progesterone, converted from PREGNENOLONE, also serves as an intermediate in the biosynthesis of GONADAL STEROID HORMONES and adrenal CORTICOSTEROIDS.

The prophase of the first division of MEIOSIS (in which homologous CHROMOSOME SEGREGATION occurs). It is divided into five stages: leptonema, zygonema, PACHYNEMA, diplonema, and diakinesis.

Clinical and laboratory techniques used to enhance fertility in humans and animals.

A microtubule structure that forms during CELL DIVISION. It consists of two SPINDLE POLES, and sets of MICROTUBULES that may include the astral microtubules, the polar microtubules, and the kinetochore microtubules.

In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)

A colorless, odorless, viscous dihydroxy alcohol. It has a sweet taste, but is poisonous if ingested. Ethylene glycol is the most important glycol commercially available and is manufactured on a large scale in the United States. It is used as an antifreeze and coolant, in hydraulic fluids, and in the manufacture of low-freezing dynamites and resins.

The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.

The active production and accumulation of VITELLINS (egg yolk proteins) in the non-mammalian OOCYTES from circulating precursors, VITELLOGENINS. Vitellogenesis usually begins after the first MEIOSIS and is regulated by estrogenic hormones.

Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).

Retrovirus-associated DNA sequences (mos) originally isolated from the Moloney murine sarcoma virus (Mo-MSV). The proto-oncogene mos (c-mos) codes for a protein which is a member of the serine kinase family. There is no evidence as yet that human c-mos can become transformed or has a role in human cancer. However, in mice, activation can occur when the retrovirus-like intracisternal A-particle inserts itself near the c-mos sequence. The human c-mos gene is located at 8q22 on the long arm of chromosome 8.

The first phase of cell nucleus division, in which the CHROMOSOMES become visible, the CELL NUCLEUS starts to lose its identity, the SPINDLE APPARATUS appears, and the CENTRIOLES migrate toward opposite poles.

The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.

Hormones that stimulate gonadal functions such as GAMETOGENESIS and sex steroid hormone production in the OVARY and the TESTIS. Major gonadotropins are glycoproteins produced primarily by the adenohypophysis (GONADOTROPINS, PITUITARY) and the placenta (CHORIONIC GONADOTROPIN). In some species, pituitary PROLACTIN and PLACENTAL LACTOGEN exert some luteotropic activities.

Occurrence or induction of release of more ova than are normally released at the same time in a given species. The term applies to both animals and humans.

A bone morphogenetic protein that plays an essential role in the regulation of ovarian folliculogenesis.

Undifferentiated cells resulting from cleavage of a fertilized egg (ZYGOTE). Inside the intact ZONA PELLUCIDA, each cleavage yields two blastomeres of about half size of the parent cell. Up to the 8-cell stage, all of the blastomeres are totipotent. The 16-cell MORULA contains outer cells and inner cells.

A protein that plays a role in GRANULOSA CELLS where it regulates folliculogenesis. Mutations in the gene for bone morphogenetic protein 15 are linked to reproductive abnormalities such as PREMATURE OVARIAN FAILURE.

Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action during the developmental stages of an organism.

Phosphoprotein with protein kinase activity that functions in the G2/M phase transition of the CELL CYCLE. It is the catalytic subunit of the MATURATION-PROMOTING FACTOR and complexes with both CYCLIN A and CYCLIN B in mammalian cells. The maximal activity of cyclin-dependent kinase 1 is achieved when it is fully dephosphorylated.

Elements of limited time intervals, contributing to particular results or situations.

The anterior portion of the spermatozoon (SPERMATOZOA) that contains mainly the nucleus with highly compact CHROMATIN material.

The chromosomal constitution of cells which deviate from the normal by the addition or subtraction of CHROMOSOMES, chromosome pairs, or chromosome fragments. In a normally diploid cell (DIPLOIDY) the loss of a chromosome pair is termed nullisomy (symbol: 2N-2), the loss of a single chromosome is MONOSOMY (symbol: 2N-1), the addition of a chromosome pair is tetrasomy (symbol: 2N+2), the addition of a single chromosome is TRISOMY (symbol: 2N+1).

The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.

Slender, cylindrical filaments found in the cytoskeleton of plant and animal cells. They are composed of the protein TUBULIN and are influenced by TUBULIN MODULATORS.

Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.

Methods pertaining to the generation of new individuals, including techniques used in selective BREEDING, cloning (CLONING, ORGANISM), and assisted reproduction (REPRODUCTIVE TECHNIQUES, ASSISTED).

Endometrial implantation of EMBRYO, MAMMALIAN at the BLASTOCYST stage.

The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).

Inability to reproduce after a specified period of unprotected intercourse. Reproductive sterility is permanent infertility.

Embryonic and fetal development that takes place in an artificial environment in vitro.

A light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.

Gonadotropins secreted by the pituitary or the placenta in horses. This term generally refers to the gonadotropins found in the pregnant mare serum, a rich source of equine CHORIONIC GONADOTROPIN; LUTEINIZING HORMONE; and FOLLICLE STIMULATING HORMONE. Unlike that in humans, the equine LUTEINIZING HORMONE, BETA SUBUNIT is identical to the equine choronic gonadotropin, beta. Equine gonadotropins prepared from pregnant mare serum are used in reproductive studies.

An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used.

A cyclin subtype that is transported into the CELL NUCLEUS at the end of the G2 PHASE. It stimulates the G2/M phase transition by activating CDC2 PROTEIN KINASE.

The capacity to conceive or to induce conception. It may refer to either the male or female.

The decrease in the cell's ability to proliferate with the passing of time. Each cell is programmed for a certain number of cell divisions and at the end of that time proliferation halts. The cell enters a quiescent state after which it experiences CELL DEATH via the process of APOPTOSIS.

The biosynthesis of PEPTIDES and PROTEINS on RIBOSOMES, directed by MESSENGER RNA, via TRANSFER RNA that is charged with standard proteinogenic AMINO ACIDS.

Steroids with methyl groups at C-10 and C-13 and a branched 8-carbon chain at C-17. Members include compounds with any degree of unsaturation; however, CHOLESTADIENES is available for derivatives containing two double bonds.

Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.

A clear, colorless, viscous organic solvent and diluent used in pharmaceutical preparations.

The rate dynamics in chemical or physical systems.

Proteins prepared by recombinant DNA technology.

Results of conception and ensuing pregnancy, including LIVE BIRTH; STILLBIRTH; SPONTANEOUS ABORTION; INDUCED ABORTION. The outcome may follow natural or artificial insemination or any of the various ASSISTED REPRODUCTIVE TECHNIQUES, such as EMBRYO TRANSFER or FERTILIZATION IN VITRO.

The procedure of removing TISSUES, organs, or specimens from DONORS for reuse, such as TRANSPLANTATION.

A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.

The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.

The 17-beta-isomer of estradiol, an aromatized C18 steroid with hydroxyl group at 3-beta- and 17-beta-position. Estradiol-17-beta is the most potent form of mammalian estrogenic steroids.

A cyclin B subtype that colocalizes with MICROTUBULES during INTERPHASE and is transported into the CELL NUCLEUS at the end of the G2 PHASE.

The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.

Phospholipoglycoproteins produced in the fat body of egg-laying animals such as non-mammalian VERTEBRATES; ARTHROPODS; and others. Vitellogenins are secreted into the HEMOLYMPH, and taken into the OOCYTES by receptor-mediated ENDOCYTOSIS to form the major yolk proteins, VITELLINS. Vitellogenin production is under the regulation of steroid hormones, such as ESTRADIOL and JUVENILE HORMONES in insects.

Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.

A polynucleotide consisting essentially of chains with a repeating backbone of phosphate and ribose units to which nitrogenous bases are attached. RNA is unique among biological macromolecules in that it can encode genetic information, serve as an abundant structural component of cells, and also possesses catalytic activity. (Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)

The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.

The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.

Messenger RNA that is stored in a masked state for translation at a later time. Distinguish from RNA, UNTRANSLATED which refers to non-messenger RNA, i.e. RNA that does not code for protein.

The material of CHROMOSOMES. It is a complex of DNA; HISTONES; and nonhistone proteins (CHROMOSOMAL PROTEINS, NON-HISTONE) found within the nucleus of a cell.

The opening and closing of ion channels due to a stimulus. The stimulus can be a change in membrane potential (voltage-gated), drugs or chemical transmitters (ligand-gated), or a mechanical deformation. Gating is thought to involve conformational changes of the ion channel which alters selective permeability.

The plasma membrane of the egg.

Methods for maintaining or growing CELLS in vitro.

Extracts of urine from menopausal women that contain high concentrations of pituitary gonadotropins, FOLLICLE STIMULATING HORMONE and LUTEINIZING HORMONE. Menotropins are used to treat infertility. The FSH:LH ratio and degree of purity vary in different preparations.

The developmental entity of a fertilized egg (ZYGOTE) in animal species other than MAMMALS. For chickens, use CHICK EMBRYO.

Single-stranded complementary DNA synthesized from an RNA template by the action of RNA-dependent DNA polymerase. cDNA (i.e., complementary DNA, not circular DNA, not C-DNA) is used in a variety of molecular cloning experiments as well as serving as a specific hybridization probe.

Proteins that originate from insect species belonging to the genus DROSOPHILA. The proteins from the most intensely studied species of Drosophila, DROSOPHILA MELANOGASTER, are the subject of much interest in the area of MORPHOGENESIS and development.

Metabolites or derivatives of PROGESTERONE with hydroxyl group substitution at various sites.

Transport proteins that carry specific substances in the blood or across cell membranes.

Cell membrane glycoproteins that are selectively permeable to potassium ions. At least eight major groups of K channels exist and they are made up of dozens of different subunits.

The reproductive cells in multicellular organisms at various stages during GAMETOGENESIS.

The relationship between the dose of an administered drug and the response of the organism to the drug.

Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.

A family of histone molecular chaperones that play roles in sperm CHROMATIN decondensation and CHROMATIN ASSEMBLY in fertilized eggs. They were originally discovered in XENOPUS egg extracts as histone-binding factors that mediate nucleosome formation in vitro.

A species of the true toads, Bufonidae, found in South America.

Methods of maintaining or growing biological materials in controlled laboratory conditions. These include the cultures of CELLS; TISSUES; organs; or embryo in vitro. Both animal and plant tissues may be cultured by a variety of methods. Cultures may derive from normal or abnormal tissues, and consist of a single cell type or mixed cell types.

A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Luteinizing hormone regulates steroid production by the interstitial cells of the TESTIS and the OVARY. The preovulatory LUTEINIZING HORMONE surge in females induces OVULATION, and subsequent LUTEINIZATION of the follicle. LUTEINIZING HORMONE consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH and FSH), but the beta subunit is unique and confers its biological specificity.

The inability of the male to effect FERTILIZATION of an OVUM after a specified period of unprotected intercourse. Male sterility is permanent infertility.

A method of providing future reproductive opportunities before a medical treatment with known risk of loss of fertility. Typically reproductive organs or tissues (e.g., sperm, egg, embryos and ovarian or testicular tissues) are cryopreserved for future use before the medical treatment (e.g., chemotherapy, radiation) begins.

Chemical agents that increase the permeability of biological or artificial lipid membranes to specific ions. Most ionophores are relatively small organic molecules that act as mobile carriers within membranes or coalesce to form ion permeable channels across membranes. Many are antibiotics, and many act as uncoupling agents by short-circuiting the proton gradient across mitochondrial membranes.

A purine and a reaction intermediate in the metabolism of adenosine and in the formation of nucleic acids by the salvage pathway.

The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.

The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.

Complex nucleoprotein structures which contain the genomic DNA and are part of the CELL NUCLEUS of MAMMALS.

Within most types of eukaryotic CELL NUCLEUS, a distinct region, not delimited by a membrane, in which some species of rRNA (RNA, RIBOSOMAL) are synthesized and assembled into ribonucleoprotein subunits of ribosomes. In the nucleolus rRNA is transcribed from a nucleolar organizer, i.e., a group of tandemly repeated chromosomal genes which encode rRNA and which are transcribed by RNA polymerase I. (Singleton & Sainsbury, Dictionary of Microbiology & Molecular Biology, 2d ed)

The process by which semen is kept viable outside of the organism from which it was derived (i.e., kept from decay by means of a chemical agent, cooling, or a fluid substitute that mimics the natural state within the organism).

A group of adenine ribonucleotides in which the phosphate residues of each adenine ribonucleotide act as bridges in forming diester linkages between the ribose moieties.

A small whitish spot on the surface of the EGG YOLK where cleavage begins. Upon fertilization the cytoplasm streams from the vegetal pole away from the yolk to the animal pole where cleavage will occur. This germinal area eventually flattens into a layer of cells (BLASTODERM) that covers the yolk completely.

A complication of OVULATION INDUCTION in infertility treatment. It is graded by the severity of symptoms which include OVARY enlargement, multiple OVARIAN FOLLICLES; OVARIAN CYSTS; ASCITES; and generalized EDEMA. The full-blown syndrome may lead to RENAL FAILURE, respiratory distress, and even DEATH. Increased capillary permeability is caused by the vasoactive substances, such as VASCULAR ENDOTHELIAL GROWTH FACTORS, secreted by the overly-stimulated OVARIES.

Euploid female germ cells of an early stage of OOGENESIS, derived from primordial germ cells during ovarian differentiation. Oogonia undergo MEIOSIS and give rise to haploid OOCYTES

The structural and functional changes by which SPERMATOZOA become capable of oocyte FERTILIZATION. It normally requires exposing the sperm to the female genital tract for a period of time to bring about increased SPERM MOTILITY and the ACROSOME REACTION before fertilization in the FALLOPIAN TUBES can take place.

A genus of small, two-winged flies containing approximately 900 described species. These organisms are the most extensively studied of all genera from the standpoint of genetics and cytology.

A potent cyclic nucleotide phosphodiesterase inhibitor; due to this action, the compound increases cyclic AMP and cyclic GMP in tissue and thereby activates CYCLIC NUCLEOTIDE-REGULATED PROTEIN KINASES

Orientation of intracellular structures especially with respect to the apical and basolateral domains of the plasma membrane. Polarized cells must direct proteins from the Golgi apparatus to the appropriate domain since tight junctions prevent proteins from diffusing between the two domains.

Nocodazole is an antineoplastic agent which exerts its effect by depolymerizing microtubules.

The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.

Large, hoofed mammals of the family EQUIDAE. Horses are active day and night with most of the day spent seeking and consuming food. Feeding peaks occur in the early morning and late afternoon, and there are several daily periods of rest.

A cyclic nucleotide phosphodiesterase subfamily that is inhibited by the binding of CYCLIC GMP to an allosteric domain found on the enzyme and through phosphorylation by regulatory kinases such as PROTEIN KINASE A and PROTEIN KINASE B. The two members of this family are referred to as type 3A, and type 3B, and are each product of a distinct gene. In addition multiple enzyme variants of each subtype can be produced due to multiple alternative mRNA splicing.

Movement characteristics of SPERMATOZOA in a fresh specimen. It is measured as the percentage of sperms that are moving, and as the percentage of sperms with productive flagellar motion such as rapid, linear, and forward progression.

A species of SWINE, in the family Suidae, comprising a number of subspecies including the domestic pig Sus scrofa domestica.

A genus of surf clams in the family Mactridae, class BIVALVIA. They are often used in EMBRYOLOGY research.

The period of the MENSTRUAL CYCLE representing follicular growth, increase in ovarian estrogen (ESTROGENS) production, and epithelial proliferation of the ENDOMETRIUM. Follicular phase begins with the onset of MENSTRUATION and ends with OVULATION.

Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.

Liquids transforming into solids by the removal of heat.

The orderly segregation of CHROMOSOMES during MEIOSIS or MITOSIS.

A class in the phylum MOLLUSCA comprised of mussels; clams; OYSTERS; COCKLES; and SCALLOPS. They are characterized by a bilaterally symmetrical hinged shell and a muscular foot used for burrowing and anchoring.

Aquaporin 1 forms a water-specific channel that is constitutively expressed at the PLASMA MEMBRANE of ERYTHROCYTES and KIDNEY TUBULES, PROXIMAL. It provides these cells with a high permeability to WATER. In humans polymorphisms of this protein result in the Colton blood group antigen.

A pair of highly specialized muscular canals extending from the UTERUS to its corresponding OVARY. They provide the means for OVUM collection, and the site for the final maturation of gametes and FERTILIZATION. The fallopian tube consists of an interstitium, an isthmus, an ampulla, an infundibulum, and fimbriae. Its wall consists of three histologic layers: serous, muscular, and an internal mucosal layer lined with both ciliated and secretory cells.

The event that a FETUS is born alive with heartbeats or RESPIRATION regardless of GESTATIONAL AGE. Such liveborn is called a newborn infant (INFANT, NEWBORN).

Gated, ion-selective glycoproteins that traverse membranes. The stimulus for ION CHANNEL GATING can be due to a variety of stimuli such as LIGANDS, a TRANSMEMBRANE POTENTIAL DIFFERENCE, mechanical deformation or through INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS.

Intracellular messenger formed by the action of phospholipase C on phosphatidylinositol 4,5-bisphosphate, which is one of the phospholipids that make up the cell membrane. Inositol 1,4,5-trisphosphate is released into the cytoplasm where it releases calcium ions from internal stores within the cell's endoplasmic reticulum. These calcium ions stimulate the activity of B kinase or calmodulin.

Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.

Male germ cells derived from the haploid secondary SPERMATOCYTES. Without further division, spermatids undergo structural changes and give rise to SPERMATOZOA.

Ion channels that specifically allow the passage of SODIUM ions. A variety of specific sodium channel subtypes are involved in serving specialized functions such as neuronal signaling, CARDIAC MUSCLE contraction, and KIDNEY function.

The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.

The ability of a substrate to allow the passage of ELECTRONS.

The degeneration and resorption of an OVARIAN FOLLICLE before it reaches maturity and ruptures.

Proteins that bind to RNA molecules. Included here are RIBONUCLEOPROTEINS and other proteins whose function is to bind specifically to RNA.

Changes that occur to liberate the enzymes of the ACROSOME of a sperm (SPERMATOZOA). Acrosome reaction allows the sperm to penetrate the ZONA PELLUCIDA and enter the OVUM during FERTILIZATION.

A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.

The cap-like structure covering the anterior portion of SPERM HEAD. Acrosome, derived from LYSOSOMES, is a membrane-bound organelle that contains the required hydrolytic and proteolytic enzymes necessary for sperm penetration of the egg in FERTILIZATION.

An aspect of protein kinase (EC 2.7.1.37) in which serine residues in protamines and histones are phosphorylated in the presence of ATP.

A species of fruit fly much used in genetics because of the large size of its chromosomes.

A major gonadotropin secreted by the human adenohypophysis (PITUITARY GLAND, ANTERIOR). Follicle-stimulating hormone stimulates GAMETOGENESIS and the supporting cells such as the ovarian GRANULOSA CELLS, the testicular SERTOLI CELLS, and the LEYDIG CELLS. FSH consists of two noncovalently linked subunits, alpha and beta. The alpha subunit is common in the three human pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity.

A type of CELL NUCLEUS division by means of which the two daughter nuclei normally receive identical complements of the number of CHROMOSOMES of the somatic cells of the species.

A decapeptide that stimulates the synthesis and secretion of both pituitary gonadotropins, LUTEINIZING HORMONE and FOLLICLE STIMULATING HORMONE. GnRH is produced by neurons in the septum PREOPTIC AREA of the HYPOTHALAMUS and released into the pituitary portal blood, leading to stimulation of GONADOTROPHS in the ANTERIOR PITUITARY GLAND.

Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.

An amorphous region of electron dense material in the cytoplasm from which the MICROTUBULES polymerization is nucleated. The pericentriolar region of the CENTROSOME which surrounds the CENTRIOLES is an example.

A purine base and a fundamental unit of ADENINE NUCLEOTIDES.

A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.

A microtubule subunit protein found in large quantities in mammalian brain. It has also been isolated from SPERM FLAGELLUM; CILIA; and other sources. Structurally, the protein is a dimer with a molecular weight of approximately 120,000 and a sedimentation coefficient of 5.8S. It binds to COLCHICINE; VINCRISTINE; and VINBLASTINE.

Cessation of ovarian function after MENARCHE but before the age of 40, without or with OVARIAN FOLLICLE depletion. It is characterized by the presence of OLIGOMENORRHEA or AMENORRHEA, elevated GONADOTROPINS, and low ESTRADIOL levels. It is a state of female HYPERGONADOTROPIC HYPOGONADISM. Etiologies include genetic defects, autoimmune processes, chemotherapy, radiation, and infections.

A species of nematode that is widely used in biological, biochemical, and genetic studies.

A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).

Connections between cells which allow passage of small molecules and electric current. Gap junctions were first described anatomically as regions of close apposition between cells with a narrow (1-2 nm) gap between cell membranes. The variety in the properties of gap junctions is reflected in the number of CONNEXINS, the family of proteins which form the junctions.

A technique that localizes specific nucleic acid sequences within intact chromosomes, eukaryotic cells, or bacterial cells through the use of specific nucleic acid-labeled probes.

A class of porins that allow the passage of WATER and other small molecules across CELL MEMBRANES.

A glycoprotein that causes regression of MULLERIAN DUCTS. It is produced by SERTOLI CELLS of the TESTES. In the absence of this hormone, the Mullerian ducts develop into structures of the female reproductive tract. In males, defects of this hormone result in persistent Mullerian duct, a form of MALE PSEUDOHERMAPHRODITISM.

Histochemical localization of immunoreactive substances using labeled antibodies as reagents.

Potassium channels where the flow of K+ ions into the cell is greater than the outward flow.

Sodium channels found on salt-reabsorbing EPITHELIAL CELLS that line the distal NEPHRON; the distal COLON; SALIVARY DUCTS; SWEAT GLANDS; and the LUNG. They are AMILORIDE-sensitive and play a critical role in the control of sodium balance, BLOOD VOLUME, and BLOOD PRESSURE.

Achievement of full sexual capacity in animals and in humans.

A complex disorder characterized by infertility, HIRSUTISM; OBESITY; and various menstrual disturbances such as OLIGOMENORRHEA; AMENORRHEA; ANOVULATION. Polycystic ovary syndrome is usually associated with bilateral enlarged ovaries studded with atretic follicles, not with cysts. The term, polycystic ovary, is misleading.

Small chromosomal proteins (approx 12-20 kD) possessing an open, unfolded structure and attached to the DNA in cell nuclei by ionic linkages. Classification into the various types (designated histone I, histone II, etc.) is based on the relative amounts of arginine and lysine in each.

Transforming proteins coded by mos oncogenes. The v-mos proteins were originally isolated from the Moloney murine sarcoma virus (Mo-MSV).

Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.

The age of the mother in PREGNANCY.

A highly polar organic liquid, that is used widely as a chemical solvent. Because of its ability to penetrate biological membranes, it is used as a vehicle for topical application of pharmaceuticals. It is also used to protect tissue during CRYOPRESERVATION. Dimethyl sulfoxide shows a range of pharmacological activity including analgesia and anti-inflammation.

In gonochoristic organisms, congenital conditions in which development of chromosomal, gonadal, or anatomical sex is atypical. Effects from exposure to abnormal levels of GONADAL HORMONES in the maternal environment, or disruption of the function of those hormones by ENDOCRINE DISRUPTORS are included.

Warm-blooded vertebrate animals belonging to the class Mammalia, including all that possess hair and suckle their young.

An adenine nucleotide containing one phosphate group which is esterified to both the 3'- and 5'-positions of the sugar moiety. It is a second messenger and a key intracellular regulator, functioning as a mediator of activity for a number of hormones, including epinephrine, glucagon, and ACTH.

Bcl-2 regulates amplification of caspase activation by cytochrome c. (1/15764)

Caspases, a family of specific proteases, have central roles in apoptosis [1]. Caspase activation in response to diverse apoptotic stimuli involves the relocalisation of cytochrome c from mitochondria to the cytoplasm where it stimulates the proteolytic processing of caspase precursors. Cytochrome c release is controlled by members of the Bcl-2 family of apoptosis regulators [2] [3]. The anti-apoptotic members Bcl-2 and Bcl-xL may also control caspase activation independently of cytochrome c relocalisation or may inhibit a positive feedback mechanism [4] [5] [6] [7]. Here, we investigate the role of Bcl-2 family proteins in the regulation of caspase activation using a model cell-free system. We found that Bcl-2 and Bcl-xL set a threshold in the amount of cytochrome c required to activate caspases, even in soluble extracts lacking mitochondria. Addition of dATP (which stimulates the procaspase-processing factor Apaf-1 [8] [9]) overcame inhibition of caspase activation by Bcl-2, but did not prevent the control of cytochrome c release from mitochondria by Bcl-2. Cytochrome c release was accelerated by active caspase-3 and this positive feedback was negatively regulated by Bcl-2. These results provide evidence for a mechanism to amplify caspase activation that is suppressed at several distinct steps by Bcl-2, even after cytochrome c is released from mitochondria. (+info)

The mitogen-activated protein kinase signaling pathway stimulates mos mRNA cytoplasmic polyadenylation during Xenopus oocyte maturation. (2/15764)

The Mos protein kinase is a key regulator of vertebrate oocyte maturation. Oocyte-specific Mos protein expression is subject to translational control. In the frog Xenopus, the translation of Mos protein requires the progesterone-induced polyadenylation of the maternal Mos mRNA, which is present in the oocyte cytoplasm. Both the Xenopus p42 mitogen-activated protein kinase (MAPK) and maturation-promoting factor (MPF) signaling pathways have been proposed to mediate progesterone-stimulated oocyte maturation. In this study, we have determined the relative contributions of the MAPK and MPF signaling pathways to Mos mRNA polyadenylation. We report that progesterone-induced Mos mRNA polyadenylation was attenuated in oocytes expressing the MAPK phosphatase rVH6. Moreover, inhibition of MAPK signaling blocked progesterone-induced Mos protein accumulation. Activation of the MAPK pathway by injection of RNA encoding Mos was sufficient to induce both the polyadenylation of synthetic Mos mRNA substrates and the accumulation of endogenous Mos protein in the absence of MPF signaling. Activation of MPF, by injection of cyclin B1 RNA or purified cyclin B1 protein, also induced both Mos protein accumulation and Mos mRNA polyadenylation. However, this action of MPF required MAPK activity. By contrast, the cytoplasmic polyadenylation of maternal cyclin B1 mRNA was stimulated by MPF in a MAPK-independent manner, thus revealing a differential regulation of maternal mRNA polyadenylation by the MAPK and MPF signaling pathways. We propose that MAPK-stimulated Mos mRNA cytoplasmic polyadenylation is a key component of the positive-feedback loop, which contributes to the all-or-none process of oocyte maturation. (+info)

Molecular dynamics of the sodium channel pore vary with gating: interactions between P-segment motions and inactivation. (3/15764)

Disulfide trapping studies have revealed that the pore-lining (P) segments of voltage-dependent sodium channels undergo sizable motions on a subsecond time scale. Such motions of the pore may be necessary for selective ion translocation. Although traditionally viewed as separable properties, gating and permeation are now known to interact extensively in various classes of channels. We have investigated the interaction of pore motions and voltage-dependent gating in micro1 sodium channels engineered to contain two cysteines within the P segments. Rates of catalyzed internal disulfide formation (kSS) were measured in K1237C+W1531C mutant channels expressed in oocytes. During repetitive voltage-clamp depolarizations, increasing the pulse duration had biphasic effects on the kSS, which first increased to a maximum at 200 msec and then decreased with longer depolarizations. This result suggested that occupancy of an intermediate inactivation state (IM) facilitates pore motions. Consistent with the known antagonism between alkali metals and a component of slow inactivation, kSS varied inversely with external [Na+]o. We examined the converse relationship, namely the effect of pore flexibility on gating, by measuring recovery from inactivation in Y401C+E758C (YC/EC) channels. Under oxidative conditions, recovery from inactivation was slower than in a reduced environment in which the spontaneous YC/EC cross-link is disrupted. The most prominent effects were slowing of a component with intermediate recovery kinetics, with diminution of its relative amplitude. We conclude that occupancy of an intermediate inactivation state facilitates motions of the P segments; conversely, flexibility of the P segments alters an intermediate component of inactivation. (+info)

The role of oocyte transcription, the 5'UTR, and translation repression and derepression in Drosophila gurken mRNA and protein localization. (4/15764)

The establishment of the major body axes of the Drosophila egg and future embryo requires strict regulation of gurken mRNA and protein localization. Here, we show that grk mRNA and protein localization is dependent on synthesis of grk transcripts in the oocyte nucleus and on RNA localization elements in the 5' portion of the transcript. We also show that gurken mRNA and protein localization is dependent on region-specific translation of gurken transcripts and identify K10 as a probable negative regulator of gurken translation. (+info)

KCNQ4, a novel potassium channel expressed in sensory outer hair cells, is mutated in dominant deafness. (5/15764)

Potassium channels regulate electrical signaling and the ionic composition of biological fluids. Mutations in the three known genes of the KCNQ branch of the K+ channel gene family underlie inherited cardiac arrhythmias (in some cases associated with deafness) and neonatal epilepsy. We have now cloned KCNQ4, a novel member of this branch. It maps to the DFNA2 locus for a form of nonsyndromic dominant deafness. In the cochlea, it is expressed in sensory outer hair cells. A mutation in this gene in a DFNA2 pedigree changes a residue in the KCNQ4 pore region. It abolishes the potassium currents of wild-type KCNQ4 on which it exerts a strong dominant-negative effect. Whereas mutations in KCNQ1 cause deafness by affecting endolymph secretion, the mechanism leading to KCNQ4-related hearing loss is intrinsic to outer hair cells. (+info)

Differential transcriptional activity associated with chromatin configuration in fully grown mouse germinal vesicle oocytes. (6/15764)

It was previously shown that fully grown ovarian germinal vesicle (GV) oocytes of adult mice exhibit several nuclear configurations that differ essentially by the presence or absence of a ring of condensed chromatin around the nucleolus. These configurations have been termed, respectively, SN (surrounded nucleolus) and NSN (nonsurrounded nucleolus). Work from our and other laboratories has revealed ultrastructural and functional differences between these two configurations. The aims of the present study were 1) to analyze the equilibrium between the SN and the NSN population as a function of the age of the mice and the time after hCG-induced ovulation and 2) to study the polymerase I (pol I)- and polymerase II (pol II)-dependent transcription in both types of oocytes through the detection of bromouridine incorporated into nascent RNA. We show 1) that ovarian GV oocytes exhibiting the SN-type configuration can be found as soon as 17 days after birth in the C57/CBA mouse strain and 2) that the SN:NSN ratio of ovarian GV oocytes is very low just after hCG-induced ovulation and then increases progressively with the time after ovulation. Furthermore, we demonstrate that the SN configuration correlates strictly with the arrest of both pol I- and pol II-dependent transcription in mice at any age. Finally, we show that ribosomal genes are located at the outer periphery of the nucleolus in the NSN configuration and that pol I-dependent perinucleolar transcription sites correspond to specific ultrastructural features of the nucleolus. Altogether, these results provide clear-cut criteria delineating transcriptionally active GV oocytes from those that are inactive, and confirm that the SN-type configuration is mostly present in preovulatory oocytes. (+info)

Ontogeny of expression of a receptor for platelet-activating factor in mouse preimplantation embryos and the effects of fertilization and culture in vitro on its expression. (7/15764)

Platelet-activating factor (PAF; 1-o-alkyl-2-acetyl-sn-glycero-3-phosphocholine) is a potent ether phospholipid. It is one of the preimplantation embryo's autocrine growth/survival factors. It may act via a G protein-linked receptor on the embryo; however, the evidence for this is conflicting. The recent description of the intracellular form of the PAF:acetlyhydrolase enzyme as having structural homology with G proteins and Ras also suggests this as a potential intracellular receptor/transducer for PAF. This study used reverse transcription-polymerase chain reaction to examine the ontogeny of expression of the genes for these proteins in the oocyte and preimplantation-stage embryo. Transcripts for the G protein-linked PAF receptor were detected in the late 2-cell-stage embryo and in all stages from the 4-cell stage to blastocysts. They were also present in unfertilized oocytes and newly fertilized zygotes but only at relatively low levels. The incidence of expression was generally low and variable in late zygotes and early 2-cell embryos. Expression past the 2-cell stage was alpha-amanitin sensitive. The results indicated that mRNA for this receptor is a maternal transcript that was degraded during the zygote-2-cell stage. New expression of the receptor transcript required activation of the zygotic genome. Fertilization of embryos in vitro caused this transcript not to be expressed in the zygote. Culture of zygotes (irrespective of their method of fertilization) caused expression from the zygotic genome to be retarded by more than 24 h. This retardation did not occur if culture commenced at the 2-cell stage. The transcripts for the subunits of intracellular PAF:acetylhydrolase were not detected in oocytes or at any stage of embryo development examined, despite their being readily detected in control tissue. This study confirms the presence of the G protein-linked PAF receptor in the 2-cell embryo and describes for the first time its normal pattern of expression during early development. The adverse effects of in vitro fertilization (IVF) and embryo culture on the expression of this transcript may be a contributing factor for the poor viability of embryos produced in this manner. The reduced expression of PAF-receptor mRNA following IVF predicts that such embryos may have a deficiency in autocrine stimulation and also suggests that supplementation of growth media with exogenous PAF would be only partially beneficial. The effect of IVF and culture may also explain the conflicting literature. (+info)

An intact sperm nuclear matrix may be necessary for the mouse paternal genome to participate in embryonic development. (8/15764)

We have been interested in determining the minimally required elements in the sperm head that are necessary in order for the paternal genome to participate in embryogenesis. We used an ionic detergent, mixed alkyltrimethylammonium bromide (ATAB), plus dithiothreitol (DTT) to remove the acrosome and almost all of the perinuclear theca, leaving only the sperm nucleus morphologically intact. We also tested the stability of the sperm nuclear matrix by the ability to form nuclear halos. Sperm nuclei washed in freshly prepared 0.5% ATAB + 2 mM DTT completely decondensed when extracted with salt, but nuclei washed in the same buffer that was 1 wk old, and then extracted with salt, produced nuclear halos, indicating stable nuclear matrices. When we treated sperm heads with freshly prepared ATAB+DTT and injected them into oocytes, none of the oocytes developed into live offspring. In contrast, sperm heads treated in the same way but with 1-wk-old ATAB+DTT solution could support development of about 30% of the oocytes to live offspring. Electron microscopy demonstrated that most of the perinuclear theca had been removed in both cases. These data suggest that at least in the mouse, the only component of the spermatozoa that is crucial for participation in embryologic development is the sperm nucleus with a stable nuclear matrix. (+info)

The oocyte is arrested in Meiosis II at the stage of metaphase II and is considered a secondary oocyte. Before ovulation, the ... An oocyte is a form of genetic material that can be collected for cryoconservation. The formation of an oocyte is called ... An oocyte (UK: /ˈoʊəsaɪt/, US: /ˈoʊoʊ-/), oöcyte, or ovocyte is a female gametocyte or germ cell involved in reproduction. In ... Oocytes are rich in cytoplasm, which contains yolk granules to nourish the cell early in development. During the primary oocyte ...

https://en.wikipedia.org/wiki/Oocyte

... is a procedure that is performed prior to in vitro fertilization, in order to use oocytes with maximal chances ... oocytes (58.5% vs. 43.9% and 5.7 vs. 5.0, respectively). Also, morphological features of the oocyte that can be obtained by ... Rienzi, L.; Vajta, G.; Ubaldi, F. (2010). "Predictive value of oocyte morphology in human IVF: a systematic review of the ... Embryos from rescued in vitro-matured metaphase II (IVM-MII) oocytes show significantly higher fertilization rates and more ...

https://en.wikipedia.org/wiki/Oocyte_selection

Oocyte (or ovum/egg) activation is a series of processes that occur in the oocyte during fertilization. Sperm entry causes ... Indications for artificial oocyte activation include : Oocyte related activation deficiency In vitro maturation Low number of ... Oocyte activation may be artificially facilitated by calcium ionophores, something that is speculated to be useful in case of ... The meiotic cycle of the oocyte was suspended in metaphase of the second meiotic division. Once PLCζ is introduced into the ...

https://en.wikipedia.org/wiki/Oocyte_activation

Degenerated oocytes are classified as damaged oocytes or oocytes without a zona pellucida. Dysmorphic oocytes are oocytes with ... Here the oocyte splits where sister chromatids migrate to the same pole and the first polar body is formed. The oocyte now ... Oocytes are immature egg cells that develop to maturity within a follicle in the ovary. Oocyte abnormalities can occur due to ... Until puberty, oocytes are kept in a dormant state in primordial follicles. At puberty the oocyte must exit its dormant stage ...

https://en.wikipedia.org/wiki/Oocyte_abnormalities

Human oocyte cryopreservation (egg freezing) is a procedure to preserve a woman's eggs (oocytes). This technique has been used ... Vitrification eliminates ice formation inside and outside of oocytes on cooling, during cryostorage and as the oocytes warm. ... with fresh oocytes when [both when] vitrified and warmed oocytes are used as part of IVF/ICSI". These studies were completed ... "Delivery rate using cyropreserved oocytes is comparable to conventional in vitro fertilization using fresh oocytes: potential ...

https://en.wikipedia.org/wiki/Oocyte_cryopreservation

... (TVOR), also referred to as oocyte retrieval (OCR), is a technique used in in vitro fertilization ... Transvaginal oocyte retrieval is more properly referred to as transvaginal ovum retrieval when the oocytes have matured into ... Steptoe and Edwards used laparoscopy to recover oocytes when IVF was introduced, and laparoscopy was the major method of oocyte ... Once the extraction is done, the sample is analyzed in the microscope to select and carry out the oocyte decumulation, a ...

https://en.wikipedia.org/wiki/Transvaginal_oocyte_retrieval

The oocyte maturation inhibitor (OMI) is an inhibitory factor created by follicular cells during a primary oocyte maturation. ... "Decline of follicular oocyte maturation inhibitor coincident with maturation and achievement of fertilizability of oocytes ... It is believed to be the reason why the oocyte remains for so long in the immature dictyate state of meiosis. Channing CP, Liu ...

https://en.wikipedia.org/wiki/Oocyte_maturation_inhibitor

In females, meiosis occurs in cells known as oocytes (singular: oocyte). Each primary oocyte divides twice in meiosis, ... Female mammals and birds are born possessing all the oocytes needed for future ovulations, and these oocytes are arrested at ... Maturing oocytes are arrested in prophase I of meiosis I and lie dormant within a protective shell of somatic cells called the ... If these oocytes are fertilized by sperm, they will resume and complete meiosis. During folliculogenesis in humans, usually one ...

https://en.wikipedia.org/wiki/Meiosis

Expression in Xenopus oocytes". FEBS Letters. 261 (2): 353-7. doi:10.1016/0014-5793(90)80590-f. PMID 1690150. Coats WD, Navarro ... J (Apr 1990). "Functional reconstitution of fMet-Leu-Phe receptor in Xenopus laevis oocytes". The Journal of Biological ...

https://en.wikipedia.org/wiki/Formyl_peptide_receptor_3

https://en.wikipedia.org/wiki/Formyl_peptide_receptor_2

Expression in Xenopus oocytes". FEBS Letters. 261 (2): 353-7. doi:10.1016/0014-5793(90)80590-f. PMID 1690150. Coats WD, Navarro ... Murphy PM, McDermott D (Jul 1991). "Functional expression of the human formyl peptide receptor in Xenopus oocytes requires a ... J (Apr 1990). "Functional reconstitution of fMet-Leu-Phe receptor in Xenopus laevis oocytes". The Journal of Biological ...

https://en.wikipedia.org/wiki/Formyl_peptide_receptor_1

The transcriptome of human oocytes. Proceedings of the National Academy of Sciences, 103(38), 14027-14032. Group, Schuler. "EST ...

https://en.wikipedia.org/wiki/Tex36

The oocyte is pierced through the oolemma and the sperm is directed into the inner part of the oocyte (cytoplasm). The sperm is ... ICSI is generally performed following a transvaginal oocyte retrieval procedure to extract one or several oocytes from a woman ... The pictured oocyte has an extruded polar body at about 12 o'clock indicating its maturity. The polar body is positioned at the ... In terms of insemination, ICSI needs only one sperm cell per oocyte, while IVF needs 50,000-100,000. This is because the ...

https://en.wikipedia.org/wiki/Intracytoplasmic_sperm_injection

In mice, Xi reactivation is known to occur in three developmental stages: In the oocyte after fertilization, the paternal X ... Kratzer, P G; Chapman, V M (May 1981). "X chromosome reactivation in oocytes of Mus caroli". Proceedings of the National ... Regarding female mouse germ cells, mature mammalian oocytes were observed to have two active X chromosomes by studies that ... Epstein, Charles J. (1969-03-07). "Mammalian Oocytes: X Chromosome Activity". Science. 163 (3871): 1078-1079. Bibcode:1969Sci ...

https://en.wikipedia.org/wiki/X-chromosome_reactivation

Males use their front and hind limbs to squeeze the sides of the corpse's belly until oocytes are ejected. The oocytes are then ...

https://en.wikipedia.org/wiki/Rhinella_proboscidea

Another experiment demonstrated that metaphase II oocyte cells were shown to have more expression of FAM76A compared to control ... sapiens metaphase II oocytes and control (consisting of a mixture of skeletal muscle, kidney, lung, colon, liver, spleen, ... "The transcriptome of human oocytes". Proceedings of the National Academy of Sciences of the United States of America. 103 (38 ... "The transcriptome of human oocytes". Proceedings of the National Academy of Sciences of the United States of America. 103 (38 ...

https://en.wikipedia.org/wiki/FAM76A

Less mature oocytes are harvested. Moreover, obesity leads to decreased pregnancy rates after IVF and a smaller chance of the ... Oocytes (but not spermatocytes) then undergo a prolonged arrest at the end of diplotene, until meiosis resumes at the beginning ... It is also possible for the uterus to have different levels of receptivity with regards to oocyte attachment, as a result of a ... During the oocyte's prolonged arrest, chromosomes exist as bivalents. This means that homologous chromosomes have paired, and ...

https://en.wikipedia.org/wiki/Ovum_quality

Pai, H. D.; Baid, R.; Palshetkar, N. P.; Pai, A.; Pai, R. D.; Palshetkar, R. (2021). "Oocyte Cryopreservation". Journal of ... "Oocyte Cryopreservation - Current Scenario and Future Perspectives: A Narrative Review", 2021, Hrishikesh D Pai,1 Rashmi Baid,1 ...

https://en.wikipedia.org/wiki/Nandita_P._Palshetkar

Donor oocyte. Oocyte donation is the most successful method for producing pregnancy in perimenopausal women. In the UK the use ... Poor ovarian reserve is a condition of low fertility characterized by 1): low numbers of remaining oocytes in the ovaries or 2 ... A 2008 study concluded that diminished reserve did not affect the quality of oocytes and any reduction in quality in diminished ... A 1995 study reported that women age fifty or higher experience similar pregnancy rates after oocyte donation as younger women ...

https://en.wikipedia.org/wiki/Poor_ovarian_reserve

Oocytes and spermatocytes are reproductive cells. Sclerocytes secrete the mineralized spicules ("little spines") that form the ... Mesohyl Pinacocyte Choanocyte Lophocyte Porocyte Oocyte Archeocyte Sclerocyte Spicule Water flow A sponge's body is hollow and ...

https://en.wikipedia.org/wiki/Sponge

Some lines of iPSCs have the potential to differentiate into male germ cells and oocyte-like cells in an appropriate niche (by ... October 2011). "Human oocytes reprogram somatic cells to a pluripotent state". Nature. 478 (7367): 70-5. Bibcode:2011Natur.478 ... Hayashi K, Ogushi S, Kurimoto K, Shimamoto S, Ohta H, Saitou M (November 2012). "Offspring from oocytes derived from in vitro ... Gurdon JB, Wilmut I (June 2011). "Nuclear transfer to eggs and oocytes". Cold Spring Harbor Perspectives in Biology. 3 (6): ...

https://en.wikipedia.org/wiki/Induced_stem_cells

... oocytes are well suited for this research as they are large and easy to handle, transparent, simple to maintain in sea ... Female starfish produce large numbers of oocytes that are easily isolated; these can be stored in a pre-meiosis phase and ... "Cytoskeletal dynamics and function in oocytes". European Molecular Biology Laboratory. Archived from the original on 1 August ...

https://en.wikipedia.org/wiki/Starfish

Xu YW, Wang B, Ding CH, Li T, Gu F, Zhou C (June 2011). "Differentially expressed micoRNAs in human oocytes". Journal of ...

https://en.wikipedia.org/wiki/Mir-625_microRNA_precursor_family

"Genome Analyses of Single Human Oocytes". Cell. 155 (7): 1492-1506. doi:10.1016/j.cell.2013.11.040. PMID 24360273. Zong, ...

https://en.wikipedia.org/wiki/Xiaoliang_Sunney_Xie

Oocyte maturation is the following phase of oocyte development. It occurs at sexual maturity when hormones stimulate the oocyte ... Oocyte maturation stands by at metaphase II in most vertebrates. During ovulation, the arrested secondary oocyte leaves the ... Most follicular granulosa cells stay around the oocyte and so form the cumulus layer. Large non-mammalian oocytes accumulate ... These cells are connected by cytoplasmic bridges with oocytes. The nurse cells of insects provide oocytes macromolecules such ...

https://en.wikipedia.org/wiki/Germ_cell

Female oocytes measure 1.5 mm in length. Barratt, I. & Allcock, L. (2014). "Abraliopsis felis". The IUCN Red List of Threatened ...

https://en.wikipedia.org/wiki/Abraliopsis_felis

Adolescents have enlarged oviducal glands with distinguishable oocytes and no or few corpora lutea. Adults have large ovaries ... and vitellogenic oocytes. Spermatozoa has been observed in preovulatory females. Juvenile males have soft, small claspers and ...

https://en.wikipedia.org/wiki/Dusky_smooth-hound

... increased both their peak currents in oocyte expression studies, and slowed the activation of the latter., KCNE1 also ... Finally, KCNE1 inhibited Kv12.2 in Xenopus oocytes. The large majority of studies into the structural basis for KCNE1 ... No effects were observed upon oocyte co-expression of KCNE1 and Kv4.2, but KCNE1 was found to slow the gating and increase ... subunits in Xenopus oocytes". Cellular Physiology and Biochemistry. 18 (1-3): 57-66. doi:10.1159/000095158. PMID 16914890. ...

https://en.wikipedia.org/wiki/KCNE1

To understand why the method was unsuccessful, they began comparing duplex RNA in both oocytes and embryos. This led them to ... Previous research on Xenopus oocytes was successful. However, when Bass and Weintraub applied identical protocols to Xenopus ...

https://en.wikipedia.org/wiki/ADAR

The insect vitelline envelope is the outer proteinaceous layer outside the oocyte and egg. The vitelline envelope, not being a ... This layer thins as the oocyte grows to reach a final thickness of ~0.4 um. Upon egg activation, peroxidase-mediated ... Calcium waves occur as Drosophila oocytes activate. Proceedings of the National Academy of Sciences of the United States of ...

https://en.wikipedia.org/wiki/Vitelline_envelope

What is the relationship between the number of oocytes retrieved during IVF and the risk of serious, potentially life ... Number of oocytes retrieved. ,10. 10-14. 15-19. ≥20. Total. codes. Number of oocyte retrievals. 44 312. 20 827. 8919. 3898. 77 ... per oocyte retrieval, increased up to approximately 20 oocytes where it reached 45.8%. The adjusted odds ratio (AOR) for live ... if a higher number of oocytes is retrieved. A high number of retrieved oocytes is also associated with a higher risk of ovarian ...

http://www.medscape.com/viewarticle/891062

You have to enable JavaScript in your browsers settings in order to use the eReader.. Or try downloading the content offline. DOWNLOAD ...

https://ehp.niehs.nih.gov/doi/epdf/10.1289/ehp.793141

... o interaction between oocytes and surrounding somatic cells o culture of oocyte-cumulus complexes o regulation of oocyte cell ... target of this RFA is to study oocyte maturation in which the oocyte undergoes germinal vesicle break down (GVBD), first polar ... o regulation of growth and differentiation of oocytes o regulation of meiosis o role of hormones in oocyte maturation in vitro ... Full Text HD-94-004 GENETICS AND PHYSIOLOGY OF HUMAN OOCYTES NIH GUIDE, Volume 22, Number 17, April 30, 1993 RFA: HD-94-004 P.T ...

https://grants.nih.gov/grants/guide/rfa-files/RFA-HD-94-004.html

A technique used in in vitro fertilization for retrieval of oocytes (eggs) from the ovaries. While this technique is also used ... oocyte. Mens magazines. pap smear. How about NO. ultrasound. The next 100 years according to Sir Arthur C. Clarke. sore throat ... A technique used in in vitro fertilization for retrieval of oocytes (eggs) from the ovaries. While this technique is also used ... hCG induces a response in the granulosa cells which surround each oocyte inside the follicles. In response to the trigger ...

https://everything2.com/title/Transvaginal+Oocyte+Retrieval

BALTIMORE, MD. (SatireWire.com) - A sperm cells hopeful attempts today to convince an egg they should "try it from behind" have so far been rejected by the egg, who called… Read more ...

https://www.satirewire.com/tag/oocyte/

... led to a significant reduction in Vg accumulation in developing oocytes. Functional assays of these two GPCRs showed that JH ... we defined the primary oocyte without yolk as the previtellogenic oocyte and the oocyte with yolk as the vitellogenic oocyte. ... However, no Vg protein was taken up into oocytes14. These studies suggest that JH signaling plays a key role in Vg uptake into ... In the meantime, yolk and lipid droplets begin to appear on day 3 PAE and accumulation of yolk or Vg in the primary oocytes ...

https://www.nature.com/articles/srep27648

Ethical issues in oocyte banking for nonautologous use: an Ethics Committee opinion (2021) From: Ethics Committee Opinions ... Planned oocyte cryopreservation for women seeking to preserve their future fertility: an Ethics Committee opinion (2018) From: ... Ethics Webinar: Planned Oocyte Cryopreservation: Medical, Ethical and Social Considerations * Micro-presentation: Fertility ... Micro-presentation: Planned Oocyte Cryopreservation for Women Seeking to Preserve Future Reproductive Potential ...

https://www.reproductivefacts.org/topics/topics-index/oocyte/

Characterization of oxygen and calcium fluxes from early mouse embryos and oocytes. by The Biological Bulletin; Biological ... APA style: Characterization of oxygen and calcium fluxes from early mouse embryos and oocytes.. (n.d.) >The Free Library. (2014 ... One reason for this gap in our knowledge lies in the difficulty in studying a single oocyte or embryo. The goal of the project ... MLA style: "Characterization of oxygen and calcium fluxes from early mouse embryos and oocytes.." The Free Library. 1998 ...

https://www.thefreelibrary.com/Characterization+of+oxygen+and+calcium+fluxes+from+early+mouse+embryos...-a053289295

... oocyte and embryo protein 19,oocyte expressed protein homolog (dog),oocyte- and embryo-specific protein 19,oocyte-expressed ... Oocyte expressed protein, alias OOEP, is a component of the subcortical maternal complex (SCMC) that play its roles in oocytes ... and it is hypotized that it could play a role in the formation/stabilization of the oocyte cytoskeleton, called oocyte ... OOEP (Oocyte expressed protein). 2019-03-01 Luigi Cristiano Affiliation Aesthetic and medical biotechnologies research unit, ...

https://atlasgeneticsoncology.org/gene/71121/ooep

Chick brain mRNA was isolated and injected into Xenopus oocytes. This led to the expression in the surface membrane of ... Allosteric modulation by benzodiazepine receptor ligands of the GABAA receptor channel expressed in Xenopus oocytes. E Sigel ... Allosteric modulation by benzodiazepine receptor ligands of the GABAA receptor channel expressed in Xenopus oocytes ... Allosteric modulation by benzodiazepine receptor ligands of the GABAA receptor channel expressed in Xenopus oocytes ...

https://www.jneurosci.org/content/8/1/289?ijkey=515623f4da08304b5530f57df31c1c258abfd099&keytype2=tf_ipsecsha

The Potential of Sperm Retrieved by Micro-TESE to Fertilize Vitrified/Warmed Oocytes. The safety and scientific validity of ... Fresh sperm retrieved by micro-TESE are used for fertilization of the warmed oocytes. when it is not possible to obtain ... Measurement of % of cleavage among the warmed oocytes. *Pregnancy rate [ Time Frame: six years ]. Measurement of serum-hCG and ... The women are stimulated with FSH in IVF protocols and the aspirated oocytes vitrified with usual applied techniques. ...

https://clinicaltrials.gov/ct2/show/NCT03809026

Metabolic control of oocyte development: linking maternal nutrition and reproductive outcomes. by Ling Gu, Honglin Liu, Xi Gu, ... To date, much of our understanding of oocyte metabolism comes from the effects of extrinsic nutrients on oocyte maturation. In ... by oocyte metabolism. Well-balanced and timed energy metabolism is critical for optimal development of oocytes. ... Metabolic control of oocyte development: linking maternal nutrition and reproductive outcomes.. Cellular and molecular life ...

https://www.sigmaaldrich.com/RU/en/tech-docs/paper/547173

... neurones was compared with that of cloned receptors expressed in Xenopus oocytes by pairwise injections of alpha 3-beta 2 or ... Comparison of neuronal nicotinic receptors in rat sympathetic neurones with subunit pairs expressed in Xenopus oocytes J ... Receptors expressed in oocytes by injection of alpha 3 and beta 2 subunits had a relatively high sensitivity to DMPP and low ... neurones was compared with that of cloned receptors expressed in Xenopus oocytes by pairwise injections of alpha 3-beta 2 or ...

https://pubmed.ncbi.nlm.nih.gov/7853248/?dopt=Abstract

... is well known that female reproduction ability decreases during the forth decade of life due to age-related changes in oocyte ... In vitro matured oocyte indicating the semiperipheral distribution of mitochondria in the oocyte. (E) In vitro matured oocyte ... Class C. Oocyte is surrounded by dispersed cumulus cells. Oocyte has a granular cytoplasm. Reproduced from Lasiene et al. (2009 ... A) GV oocyte displays the distribution of mitochondria in the peripheral zone. (B) GV oocyte with mitochondria diffused fairly ...

https://pubmed.ncbi.nlm.nih.gov/34338482/

Progesterone-mediated oocyte maturation - Xenopus laevis (African clawed frog) [ Pathway menu , Pathway entry , Download KGML ... Xenopus oocytes are naturally arrested at G2 of meiosis I. Exposure to either insulin/IGF-1 or the steroid hormone progesterone ... This process is termed oocyte maturation. The transition is accompanied by an increase in maturation promoting factor (MPF or ... breaks this arrest and induces resumption of the two meiotic division cycles and maturation of the oocyte into a mature, ...

https://www.genome.jp/pathway/xla04914

Comparison of the somatic TADs and lampbrush chromomere-loop complexes in transcriptionally active prophase I oocytes. View ... Comparison of the somatic TADs and lampbrush chromomere-loop complexes in transcriptionally active prophase I oocytes ... Comparison of the somatic TADs and lampbrush chromomere-loop complexes in transcriptionally active prophase I oocytes ... Comparison of the somatic TADs and lampbrush chromomere-loop complexes in transcriptionally active prophase I oocytes ...

https://www.biorxiv.org/content/10.1101/2021.11.30.470320v1.supplementary-material

From Embryonic Stem Cells to Oocytes: A stepwise approach to nuclear transfer therapy ... From Embryonic Stem Cells to Oocytes: A stepwise approach to nuclear transfer therapyNIH Only. ... From Embryonic Stem Cells to Oocytes: A stepwise approach to nuclear transfer therapy ...

https://videocast.nih.gov/watch=2526

... oocyte retrieval) and egg retrieval recovery from Pacific Fertility Center. PFC is a leading international center for IVF (in ...

https://www.pacificfertilitycenter.com/treatment-care/in-vitro-fertilization/ivf-tour/egg-retrieval

Analysis using Flag-tagged H3.1 transgenic mice revealed that Flag-H3.1 was not present in differentiated oocytes or early ... Differentiated oocytes acquire totipotency through fertilization. During this transition, genome-wide chromatin remodeling ...

https://www.jstage.jst.go.jp/article/jrd/58/5/58_2012-074/_article/-char/en

Calcium flux assay of chemokine receptor expression in Xenopus oocytes ... in Xenopus laevis oocytes: G alpha-16 couples to chemotactic receptors in Xenopus oocytes. Burg M, Raffetseder U, Grove M, Klos ... Expression in Xenopus oocytes. Murphy PM, Gallin EK, Tiffany HL, Malech HL. Murphy PM, et al. FEBS Lett. 1990 Feb 26;261(2):353 ... Calcium flux assay of chemokine receptor expression in Xenopus oocytes P M Murphy. Methods Enzymol. 1997. ...

http://www.ncbi.nlm.nih.gov/pubmed/9356990

... ...

https://www.contemporaryobgyn.net/view/does-chromosomal-screening-oocytes-embryo-transfer-improve-live-birth-rate

BioAssay record AID 1275134 submitted by ChEMBL: Binding affinity to alpha4beta2 nACh receptor (unknown origin) expressed in Xenopus oocytes.

https://pubchem.ncbi.nlm.nih.gov/bioassay/1275134

DCI modified the expression of genes related to oocyte quality, oxidative stress, and luteal sufficiency in cumulus-oocyte ... DCI modified the expression of genes related to oocyte quality, oxidative stress, and luteal sufficiency in cumulus-oocyte ... D-Chiro-Inositol Treatment Affects Oocyte and Embryo Quality and Improves Glucose Intolerance in Both Aged Mice and Mouse ... "D-Chiro-Inositol Treatment Affects Oocyte and Embryo Quality and Improves Glucose Intolerance in Both Aged Mice and Mouse ...

https://www.mdpi.com/1422-0067/21/17/6049

Oocyte meiosis - Homo sapiens (human) [ Pathway menu , Pathway entry , Download KGML , Show description , Image file , Help ] ... In vertebrates, immature oocytes are arrested at the PI (prophase of meiosis I). The resumption of meiosis is stimulated by ... In PI-arrested oocytes, MPF is initially inactive and is activated by the dual-specificity CDC25C phosphatase as the result of ... progesterone, which carries the oocyte through two consecutive M-phases (MI and MII) to a second arrest at MII. The key ...

https://www.kegg.jp/kegg-bin/show_pathway?map=hsa04114&mapscale=1.0&show_description=hide&multi_query=hsa:8379+red,black%0D%0A

... to evaluate how air pollution influences human reproduction using a large cohort of oocyte donors and oocyte recipient couples ... Vitrified donor oocyte ART represents an ideal population to investigate the mechanisms underlying any associations between air ... THE INFLUENCE OF AMBIENT AIR POLLUTION ON FERTILITY USING A VITRIFIED DONOR OOCYTE BANK. ... and fertility as exposures to the oocyte and uterine environment are uncorrelated in time or space and exposures to the oocyte ...

https://tools.niehs.nih.gov/portfolio/index.cfm?do=portfolio.grantDetail&grant_number=R01ES032446

Chad, J., Foreman, R. and Wheeler, S. (1989) Expression of ionic channels in Xenopus oocytes after injection of fetal human ... Expression of ionic channels in Xenopus oocytes after injection of fetal human mRNA ... Expression of ionic channels in Xenopus oocytes after injection of fetal human mRNA ... Expression of ionic channels in Xenopus oocytes after injection of fetal human mRNA ...

https://eprints.soton.ac.uk/56727/

... chorionic gonadotropin or a gonadotropin-releasing hormone agonist in gonadotropin-releasing hormone antagonist-treated oocyte ... FemaleFertilization in VitroGonadotropin-Releasing HormoneHormone AntagonistsHumansOocyte DonationOocyte RetrievalOvarian ... and incidence of moderate/severe OHSS in oocyte donors. RESULT(S): The proportion of mature oocytes was comparable, whereas the ... The use of gonadotropin-releasing hormone (GnRH) agonist to induce oocyte maturation after cotreatment with GnRH antagonist in ...

https://www.unboundmedicine.com/medline/citation/18367175/Triggering_with_human_chorionic_gonadotropin_or_a_gonadotropin_releasing_hormone_agonist_in_gonadotropin_releasing_hormone_antagonist_treated_oocyte_donor_cycles:_findings_of_a_large_retrospective_cohort_study_

Scientific Video Article |

https://www.jove.com/v/55034/xenopus-oocytes-optimized-methods-for-microinjection-removal?language=Portuguese

Oocyte efficiency: does live birth rate differ when analyzing cryopreserved and fresh oocytes on a per-oocyte basis?.. Fertil ... Oocyte efficiency: does live birth rate differ when analyzing cryopreserved and fresh oocytes on a per-oocyte basis?.. Fertil ... Oocyte efficiency: does live birth rate differ when analyzing cryopreserved and fresh oocytes on a per-oocyte basis?.. Fertil ... Oocyte efficiency: does live birth rate differ when analyzing cryopreserved and fresh oocytes on a per-oocyte basis?. ...

https://www.fertstert.org/article/S0015-0282%2814%2902381-4/fulltext

What constitutes a reasonable compensation for non-commercial oocyte donors: an analogy with living organ donation and medical ... What constitutes a reasonable compensation for non-commercial oocyte donors: an analogy with living organ donation and medical ... What constitutes a reasonable compensation for non-commercial oocyte donors: an analogy with living organ donation and medical ...

https://jme.bmj.com/content/45/11/736.share

In vitro oocyte maturation (IVM) is being increasingly approached in assisted reproductive technology (ART). (eurekamag.com)
The disruption of these regulatory circuits impairs oocyte maturation. (europa.eu)
With the MateRNA project we showed that in presence of more subtle disturbances of translation, the oocytes undergo apparently normal maturation but, once fertilized, fail to develop into an embryo. (europa.eu)
Hypothesis: the program of maternal mRNA translation during maturation is impaired in aging oocytes. (europa.eu)
Hypothesis: Temporal regulation of maternal mRNA translation is required for oocyte maturation and embryo development in monovulatory mammalian species. (europa.eu)
SO2.A: a published study analyzed transcript expression level in oocytes from young and old mice before (GV) and after (MII) maturation, concluding that a number of transcripts are lower in MII oocytes of aging mice. (europa.eu)
In Study 3, we used the FiSH technique to investigate the impact of oxidative stress on post-transcriptional regulation of mRNA translation and degradation during oocyte maturation and embryonic development. (unl.edu)
These findings suggest that obesity-dependent alterations during oocyte maturation may have the potential to contribute to early adaptive programming in the embryo and that may result in lasting effects on fetal development and/or postnatal phenotype expression. (unl.edu)
The key activity driving meiotic progression is the MPF (maturation-promoting factor), a heterodimer of CDC2 (cell division cycle 2 kinase) and cyclin B. In PI-arrested oocytes, MPF is initially inactive and is activated by the dual-specificity CDC25C phosphatase as the result of new synthesis of Mos induced by progesterone. (kegg.jp)
In conclusion, this work improves our understanding of human oocyte morphology, cytoplasmic maturation, and intracellular factors defining human egg quality. (muni.cz)
In this study, we investigated the effects of BPA exposure on porcine oocyte maturation and its possible reasons. (oncotarget.com)
Our results showed that: (i) the rates of oocyte maturation significantly decreased with 250 μM BPA treatment in vitro , but not DEHP. (oncotarget.com)
This might be due to the delayed cell cycle progression of oocyte maturation. (oncotarget.com)
Collectively, our results indicated that porcine oocytes maturation was disrupted after BPA treatment through disrupting cytoskeletal dynamics, epigenetic modifications and inducing apoptosis/autophagy. (oncotarget.com)
Since cAMP blocks meiotic maturation of mammalian and amphibian oocytes in vitro and cyclic nucleotide phosphodiesterase 3A (PDE3A) is primarily responsible for oocyte cAMP hydrolysis we generated PDE3A-deficient mice by homologous recombination. (immune-source.com)
maturation in oocytes was restored by inhibiting protein kinase A (PKA) with adenosine-3? (immune-source.com)
mice represent an in vivo model where meiotic maturation and ovulation are dissociated which underscores inhibition of oocyte maturation as a potential strategy for contraception. (immune-source.com)
Through protein kinase A-catalyzed (PKA-catalyzed) phosphorylation of unidentified proteins cAMP prevents activation of maturation-promoting factor (MPF) and MAPK signaling in Cdc42 oocytes and inhibits the spontaneous maturation that occurs in vitro thus maintaining meiotic arrest (1-5). (immune-source.com)
Endogenous RNAi pathway is essential for mouse female germline while miRNA pathway which is ubiquitously present in most cell types is dispensable for oocyte maturation and fertilization. (cuni.cz)
oogonia proliferation and transformation into the primary oocyte, primary growth phase, secondary growth phase and maturation phase and these are similar to those described for other species. (org.in)
The oocytes entered the maturation phase when they attained the maximum size of 459.6±71.83 μm. (org.in)
Oocytes collected from prepubertal calves lack developmental competence due to their failure or inability to complete ooplasmic maturation. (unimi.it)
The reduced rate of cleavage may be due to denuding required for the micromanipulation step, so, oocytes that receive a transferred GV must undergo the final stages of maturation and the early embryonic development without contacts with their cumulus cells. (unimi.it)
1998. Influence of organochlorine pesticides on maturation and post-fertilization development of bovine oocytes in vitro . (cdc.gov)
This protein is also involved in silencing of certain maternal mRNAs during oocyte maturation and early embryonic development, as well as in nonsense-mediated decay (NMD) of mRNAs that contain premature stop codons. (origene.com)
Once appropriately sized follicles develop, a dose of human chorionic gonadotropin (hCG) is administered to cause maturation of the oocytes before transvaginal oocyte retrieval. (medscape.com)
Once oocytes are located under the microscope they are placed in Maturation Media for 24 hours which simulates the process of ovulation where the oocyte normally undergoes the maturation process readying the egg for fertilization. (bova-tech.com)
Prolactin concentration in follicular fluid during in vitro fertilization (IVF) correlates with the oocyte maturation level and fertilization rate. (medscape.com)

This FiSH method allowed us to accurately and reproducibly monitor changes in candidate mRNA localization and absolute quantity in growing and mature oocytes as well as pre-implantation embryos. (unl.edu)
We show the importance of organelle-level selection, seen in the selective pooling of mitochondria into the Balbiani body, in achieving high-quality mitochondria at extreme ploidy in mature oocytes. (elifesciences.org)
The near-universality of these processes across animal taxa makes sense in light of the need to maintain mitochondrial quality at extreme ploidy in mature oocytes, in the absence of sex and recombination. (elifesciences.org)
their multiplication and differentiation are followed by the release of mature oocytes. (org.in)
The following endpoints for embryo quality and early developmental outcomes were collected: number oocytes retrieved, total number of mature oocytes, fertilization rate, and embryo grades (1-5, 1 being the best) on days 2, 3 and 5. (cdc.gov)
P=0.11) change in number of mature oocytes. (cdc.gov)
Dolmans MM, Marotta ML, Pirard C, Donnez J, Donnez O. Ovarian tissue cryopreservation followed by controlled ovarian stimulation and pick-up of mature oocytes does not impair the number or quality of retrieved oocytes. (ijfs.ir)

And embryos in IVM group were fertilized from IVM immature oocytes. (eurekamag.com)
Genome-wide maps of recombination and chromosome segregation in human oocytes and embryos show selection for maternal recombination rates. (nature.com)
In Study 2, we modified the single molecule RNA fluorescent in situ hybridization (FiSH) technique for use with oocytes and pre-implantation embryos. (unl.edu)
These experiments demonstrated that oxidative stress impaired degradation of Pou5f1 and Dppa3 in maturing oocytes resulting in increased translation of POU5F1 and DPPA3 in 1-cell and 2-cell embryos, respectively. (unl.edu)
The activities of glucose 6-phosphate dehydrogenase (G6PDH) of the follicular oocytes collected from bovine ovaries and the embryos fertilized in vitro were measured using fluorescence microscope with photomultiplier and photometer attachments. (nii.ac.jp)
Publications] Setsuo Iwasaki, Yasuo Shioya and Tatsuo Nakahara: 'Measurement of glucose 6-phosphate dehydrogenase activity in bovine oocytes and embryos using quantitative fluorescence microscopy. (nii.ac.jp)
It is suggested that persistence of a follicle alters amounts of mRNA for genes important for regulation of transcription and protein translation in the oocyte, which could compromise development of early embryos in cows that ovulate a persistent follicle. (wvu.edu)
Real time PCR analysis indicated that miR-181a was expressed in both oocytes and embryos and tended to increase at the morula and blastocyst stages (p = 0.07). (wvu.edu)
We will analyze the stimulation outcome, the number of retrieved oocytes, cleaving embryos, and pregnancy and implantation rates as well. (fertyox.pt)
In addition to age-related limitations, an immediate obstacle for obtaining oocytes in cancer patients is the fact that only one controlled ovarian hyperstimulation (COH) cycle can usually be performed in these women because of time constraints, yielding a relatively low number of oocytes and/or embryos. (ijfs.ir)
In this national registry-based diagnostic study, in 66.2% of cycles among patients younger than 38 years, fewer than all retrieved oocytes could be exposed to sperm to minimize the number of unused embryos while optimizing the probability of a live birth. (cdc.gov)

The aim of this study was to establish a culture system to support the growth of bovine oocytes as enclosed in granulosa cell complexes that extend on a flat substratum. (bioone.org)
Growing bovine oocytes with a mean diameter of 95 μm were isolated from early antral follicles: the growing stage corresponds to that of oocytes in preantral follicles of 12-day-old mice. (bioone.org)
In this study, in order to improve this competence, we transplanted nuclei isolated from GV stage calf oocytes in enucleated matured competent bovine oocytes and we demonstrated that our nuclear technique transplantation is highly effective in reconstituting calf oocyte at a rate of 76.34% and that the reconstructed oocyte can retain its ability to mature in vitro and to be normaly fertilized. (unimi.it)
Reconstruction of calf oocytes by germinal vesicle transfer in mature bovine oocytes : preliminary results / A. Lange Consiglio, A. Bignotti, A. Pecile, F. Cremonesi. (unimi.it)

The rat monocarboxylate transporter isoform MCT2 was analysed by expression in Xenopus laevis oocytes and the results were compared with the known characteristics of lactate transport in heart and brain. (portlandpress.com)
After microinjection of Xenopus laevis oocytes with RNA from avian myeloblastosis virus, viral structural proteins p27, p19, p15, and p12 are formed by a sequence of posttranslational cleavages of a high-molecular-weight precursor polypeptide. (duke.edu)
As a graduate student in the late 1960s at Berkeley, I was introduced to the Xenopus oocyte by John Gerhart, who shared his fascination with the work of John Gurdon, who had pointed out the unique and powerful features of the oocyte and egg, particularly the ability to microinject biochemically significant amounts of material into them while they carried out complex biological events. (jbc.org)
To study the role of chromatin in RA-activated transcription, we assembled the RARβ2 promoter into chromatin in Xenopus oocytes. (elsevier.com)
Influenza D virus M2 protein exhibits ion channel activity in Xenopus laevis oocytes. (cdc.gov)
The germ cell lineage in Xenopus is specified by the inheritance of germ plasm that assembles within the mitochondrial cloud or Balbiani body in stage I oocytes. (houstonmethodist.org)
All those deletion-carrying hIL-6 (delta hIL-6) proteins were then produced in Xenopus laevis oocytes and examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). (uniparthenope.it)

Fig. 2: Chromosome segregation in mammalian oocytes. (nature.com)
Fig. 3: Assembly of the meiotic spindle in mammalian oocytes. (nature.com)
Fig. 5: Age-associated defects in chromosome segregation in mammalian oocytes. (nature.com)
Fig. 6: Factors implicated in mammalian oocyte ageing. (nature.com)
Introduction Although competent to complete meiosis mammalian oocytes are physiologically arrested in prophase I (prophase of the first meiotic division) until shortly before ovulation. (immune-source.com)
Cyclic AMP apparently plays an important role in maintaining PF-04979064 meiotic arrest PF-04979064 in mammalian oocytes. (immune-source.com)
Thus, unliganded receptors expressed in oocytes are capable of accessing to the chromatin-assembled promoter and activating transcription without ligand, indicating that chromatin assembly per se is not sufficient to reproduce ligand-dependent chromatin changes and promoter activation seen in mammalian cells. (elsevier.com)

Here we report that mouse oocytes lacking FZR1 undergo passage through meiosis I that is accelerated by ~1 h, and this is due to an earlier onset of spindle assembly checkpoint (SAC) satisfaction and APC(CDC20) activity. (nih.gov)
Aneuploidy arises as a consequence of aberrant meiosis during egg development from its progenitor cell, the oocyte. (nature.com)
Fig. 1: Meiosis of human oocytes. (nature.com)
In vertebrates, immature oocytes are arrested at the PI (prophase of meiosis I). The resumption of meiosis is stimulated by progesterone, which carries the oocyte through two consecutive M-phases (MI and MII) to a second arrest at MII. (kegg.jp)
During this time, the oocyte acquires the ability to resume meiosis, undergo fertilization and sustain embryonic development. (wvu.edu)
In species from nematodes to humans, many healthy, developing oocytes apoptose around the pachytene stage of meiosis. (biologists.com)
Células germinales femeninas derivadas de OVOGONIAS cuando entran en MEIOSIS. (bvsalud.org)
Los ovocitos primarios comienzan la meiosis pero permanecen en fase de diplotene hasta que llega la PUBERTAD y se produce la OVULACIÓN, momento en el que se da lugar a los ovocitos secundarios haploides u ÓVULO. (bvsalud.org)
Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS . (bvsalud.org)
The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova ( OVUM ). (bvsalud.org)
If her mother is exposed to an environmental toxin, such as ethanol, there could be defects in meiosis, leading to long-term health effects for the baby and for babies produced from the oocytes she was developing. (mageewomens.org)

Such activation of the somatic follicular compartment promotes the translation of a subset of transcripts in the oocyte together with an increase in embryo development. (europa.eu)
We developed a genetically engineered mouse model, where AKT was constitutively activated in the oocyte to ask whether AKT activation in the oocyte induced increased translation and higher embryo rate. (europa.eu)
Three studies were conducted to determine how female obesity, which promotes a low grade inflammatory and oxidative stress environment in the ovary, alters transcriptional and post-transcriptional regulation of candidate mRNAs in oocytes and determine if these increases are functionally important in the pre-implantation embryo. (unl.edu)
The processing pattern of virus-specific precursor polypeptides is the same in X. laevis oocytes as in chick embryo fibroblasts infected with avian myeloblastosis virus, but the processing takes place at a much slower rate. (duke.edu)
English) Oocyte-to-embryo transition (OET) is one of the most complex developmental events where a differentiated oocyte gives rise to a totipotent zygote. (cuni.cz)
This study was designed to determine if exposure of rabbit intrafollicular oocytes to clomiphene citrate (CC) affects pregnancy outcome after in vitro ovulation, in vitro fertilization (IVF), and embryo transfer (ET). (edu.au)
Increased Hg levels were associated with decreased oocyte quantity, increased fertilization rate and decreased embryo quality, though none of the associations were statistically significant at the 0.05 level. (cdc.gov)
We found some evidence of a relationship between hair Hg concentrations and oocyte quantity, and a trend of an association between hair Hg levels and poorer embryo quality. (cdc.gov)
2. Nuclear transfer is a technique used to duplicate genetic material by creating an embryo through the transfer and fusion of a diploid cell in an enucleated female oocyte.2 Cloning has a broader meaning than nuclear transfer as it also involves gene replication and natural or induced embryo splitting (see Annex 1). (who.int)
Controlled ovarian stimulation (COS) followed by embryo and/or oocyte cryopreservation is the FP method recommended by both the ASCO and ISFP. (medscape.com)
The final step where the fertilized oocytes grow when placed in the culture medium and kept in incubators until evaluated for embryo quality and stage of growth. (bova-tech.com)

In human oocytes, chromosomes often segregate incorrectly. (nature.com)
Genome analyses of single human oocytes. (nature.com)
Here, we report our findings from the ultrastructural analysis of 69 unfertilized human oocytes from 34 young and healthy egg donors. (muni.cz)
Functional Human Oocytes Generated by Transfer of Polar Body Genomes. (bvsalud.org)

In the fruit fly, Drosophila melanogaster, the oocyte differentiates in a 16-cell syncytium that arises from a cystoblast which undergoes 4 synchronous divisions with incomplete cytokinesis. (biologists.com)
Transient posterior localization of a kinesin fusion protein reflects anteroposterior polarity of the Drosophila oocyte. (biologists.com)
Using Drosophila as a model, the St Johnston lab reveal a molecular mechanism underlying the oocyte specification process. (cam.ac.uk)
Here, we show that the microtubule (MT) minus end-stabilizing protein Patronin/CAMSAP marks the future Drosophila oocyte and is required for oocyte specification. (cam.ac.uk)
This interaction is conserved in Drosophila oocytes. (biologists.com)

hCG induces a response in the granulosa cells which surround each oocyte inside the follicles. (indiahospitaltour.com)
Quantitative real-time PCR was used to measure the mRNA abundance of 10 selected genes important for early embryogenesis in oocytes obtained from growing and persistent follicles. (wvu.edu)
Oocytes from persistent follicles, however, had greater abundances of PAP and eIF-4E transcripts (p (wvu.edu)
There was no significant difference between the groups for mean number of follicles ≥ 18 mm (P = 0.131), mean number of oocytes retrieved (P = 0.209) or endometrial thickness (P = 0.673). (who.int)
The recruitment of a sufficient number of growing follicles following ovarian stimulation increases the oocyte yield and subsequently the success rate after in vitro fertilization (IVF) treatment. (fertyox.pt)

Oocyte Retrieval is a technique used in In vitro fertilization for retrieval of occytes (eggs) from the ovaries. (indiahospitaltour.com)
To solve the low implantation rate of in-vitro fertilization (IVF), zona-free oocyte is widely used in IVF [1]. (elsevier.com)
[ 32 ] Following COS, oocytes are retrieved and fertilized using conventional in vitro fertilization (IVF) or intracytoplasmic sperm injection. (medscape.com)

The MateRNA project aims at investigating the relationship between the oocyte competence to sustain embryonic development and the program of maternal mRNA translation in mammals. (europa.eu)
Research suggests that the NLRP7 protein also plays a role in egg cell (oocyte) and embryonic development as well as inflammation and other immune responses by regulating the release of an immune protein called interleukin-1 beta. (medlineplus.gov)

The development and function of oocytes largely depends on cooperativity with supporting cells such as cumulus cells and granulosa cells . (copewithcytokines.de)
Experimental approach: oocytes enclosed in the cumulus cells (CEOs) were treated with hormones/growth factors/signal molecules or inhibitors of intracellular pathways. (europa.eu)
SO1.A: previous studies conducted at the Host Institution showed that EGF-like growth factors initiate a cascade in the cumulus cells that surround the oocyte. (europa.eu)
SO1.C: we performed a pharmacological screening and analyzed previously deposited databases to identify pathway(s) responsible for signal transduction between cumulus cells and activation of AKT in the oocyte. (europa.eu)
Cyclic AMP may enter oocytes from adjacent cumulus cells via gap junctions (2 6 Recent studies in rodents however demonstrated that PF-04979064 active oocyte adenylyl cyclase contributes to meiotic blockade (8) which can be released by microinjection of oocytes with antibodies that inactivate Gs the heterotrimeric GTP-binding protein that activates adenylyl cyclase (9). (immune-source.com)

In mammals and flies, only one cell in a multicellular female germline cyst becomes an oocyte, but how symmetry is broken to select the oocyte is unknown. (cam.ac.uk)
The researchers conclude that CAR-1 has a conserved role in oogenesis and propose that germline apoptosis enhances the formation of functional oocytes. (biologists.com)

Men with no spermatozoa may benefit by combining round spermatid injection (ROSI) and artificial oocyte activation (AOA). (planer.com)

In summary these collective studies identified both transcriptional and post-transcriptional changes in oocyte mRNA abundance which may be attributed to alterations in the gut microbiome, ovarian inflammation and oxidative stress. (unl.edu)
Histological examination of the mature ovaries showed the presence of all the different oocyte stages in the ovary of A. berda with an asynchronous mode of ovarian development shortly before spawning, indicating that the species is a multiple spawner. (org.in)
Risk factors for OHSS include young age, low body weight, high serum estradiol concentrations, polycystic ovaries, higher doses of gonadotropins during ovarian stimulation, and a greater number of oocytes retrieved. (medscape.com)

Secondary oocytes are haploid cells generated after birth during ovulation. (copewithcytokines.de)
The last hours of oocyte differentiation, before ovulation, are characterized by well-coordinated events that regulates cell cycle re-entry, chromosomes segregation, chromatin remodelling and reprogramming of the genome. (europa.eu)
The quality of metaphase II oocytes will undergo a time-dependent deterioration following ovulation as the result of the oocyte aging process. (scite.ai)

IMSEAR at SEARO: 35S induced dominant lethals in immature oocytes of mice. (who.int)
An oocyte is an immature egg cell that matures into an oocyte (egg) ready for fertilization. (pinkstork.com)
Similarly, a baby girl's immature egg cells, or oocytes, are developed while she is still in the womb. (mageewomens.org)

Oocyte development stages observed in A. berda were chromatin nucleolus, early perinucleolar, late perinucleolar, lipid vesicle stage I oocyte, lipid vesicle stage II oocyte, primary yolk granule stage, secondary yolk granule stage, tertiary yolk granule stage, hydrated oocyte and atretic oocyte. (org.in)

Although this analysis involved spare oocytes completing development in vitro, it provides essential insight into the enigmatic process by which human egg progenitors prepare for fertilization. (muni.cz)
oocytes that underwent germinal vesicle breakdown showed activation of MPF and MAPK completed the first meiotic division extruding a polar body and became competent for fertilization by spermatozoa. (immune-source.com)
During the growth phase an oocyte prepares for fertilization and progression to zygotic genome activation. (cuni.cz)

However the process of zona-removal is not only tedious but also easy to harm the fragile oocyte. (elsevier.com)

Mapping of epitopes on porcine zona pellucida-3 alpha by monoclonal antibodies inhibiting oocyte-sperm interaction. (oregonstate.edu)
The inadequate decondensation of the sperm chromatin, its transformation into the male pronucleus (MPN) together with the subsequent inability to activate the oocyte, seem to be the main causes of the low ICSI efficiency. (gva.es)
Alternatively, the sperm membrane was digested with Triton X-100 (TX) before ICSI, to improve the exposure of the sperm chromatin to the oocyte cytoplasm. (gva.es)
However, no significant differences between the three groups were observed in terms of the number of pronuclei, 2PN (oocytes with 2 pronuclei and no visible sperm), and 1PN + sperm (oocytes with 1 pronucleus and one sperm head). (gva.es)
However, the sperm TX pre-treatment improved oocyte activation at 6 h post-ICSI, although 22 h post-ICSI such a beneficial effect did not persist. (gva.es)
1 million sperm is added to one dish of oocytes. (bova-tech.com)

The number and quality of oocytes retrieved were evaluated and apoptosis of granolusa cells was studied. (who.int)
For this reason, results from egg donation programs cannot be extrapolated to cancer patients, nor can the quality of oocytes be guaranteed. (ijfs.ir)

Do we have any proof that boosting mitochondrial function in oocytes increases success? (uni-linz.ac.at)

During these divisions, spindle orientation is highly ordered and is thought to impart a polarity to the cyst that is necessary for the subsequent differentiation of the oocyte. (biologists.com)
Later in oogenesis, dynein function is necessary for proper differentiation, but does not appear to participate in morphogen localization within the oocyte. (biologists.com)
Growth and differentiation factor 9 promotes oocyte growth at the primary but not at the early secondary stage in three-dimensional follicle culture. (cookandersenlaboratory.com)

Oocyte Cryopreservation - Current Scenario and Future Perspectives: A Narrative Review. (nih.gov)
Currently, oocyte cryopreservation seems to be the most feasible technique for fertility preservation when there's some kind of a time constraint in adolescents and adults. (ijfs.ir)
Predicting the likelihood of live birth for elective oocyte cryopreservation: a counseling tool for physicians and patients. (ijfs.ir)

Futhermore, expression of RAR and RXR in oocytes led to local disruption of chromatin assembled over the promoter without ligand. (elsevier.com)
The oocyte system may serve as a model to study mechanisms of RA-dependent alterations of chromatin structure. (elsevier.com)
Chromatin Modification and Global Transcriptional Silencing in the Oocyte Mediated by the mRNA Decay Activator ZFP36L2. (cookandersenlaboratory.com)

As a fully-grown oocyte is a huge cell with a proportionally large maternal transcriptome we analysed the miRNA: mRNA stoichiometry changes that occur from growing to the fully-grown mouse oocyte. (cuni.cz)

ii) BPA treatment resulted in abnormal cytoskeletons on porcine oocytes, showing with aberrant actin distribution, spindle morphology and chromosome alignment, which was further confirmed by the reduced p-MAPK level. (oncotarget.com)
A pregnancy that results from an abnormal oocyte cannot develop properly, resulting in recurrent hydatidiform mole. (medlineplus.gov)

Four developmental phases of oocyte development were identified viz. (org.in)

Only oocytes arrested in metaphase II can be fertilized. (immune-source.com)

These data suggest that administration of silymarin in IVF patients concomitantly with gonadotropin results in reduction of granolusa cell apoptosis but does not have any effect in promotion of follicular development, oocyte retrieval or endometrial thickness. (who.int)

SO1: define the biochemical mechanisms by which somatic cells regulate the translational program of mouse oocytes. (europa.eu)
SO1.B: results obtained in 1A indicated PI3K/AKT as key pathway linking somatic cells activation to induction of oocyte specific translation. (europa.eu)
Such systems have been established for mouse oocytes but are not applicable to larger animals because it is difficult to maintain an appropriate association between the oocyte and companion somatic cells. (bioone.org)

Using an ultrasound guided needle oocytes (eggs) are removed from the ovaries of a super-stimulated donor cow. (bova-tech.com)

The hCG trigger injection must be precisely timed, as oocyte retrieval must happen between 34 and 36 hours after the injection. (indiahospitaltour.com)

It does so by transcribing and storing the necessary mRNAs till a fully-grown oocyte attains transcriptional quiescence. (cuni.cz)

Parental disclosure to offspring created with oocyte donation: intentions versus reality. (bvsalud.org)
Next, we are going to outline the most relevant differences of performing an egg donation treatment with vitrified or fresh oocytes. (ovoclinic.net)
One of the most frequently asked questions by patients undergoing oocyte donation treatment is: will the donor look like me? (ovoclinic.net)

These studies imply that generation of PF-04979064 intra-oocyte cAMP is sufficient to maintain meiotic arrest. (immune-source.com)

Oocytes were exposed in 20, 33, 50 and 100% vitrification solution for 2, 1 and 1 min, and 30-50 s, respectively at room temperature. (uni-koeln.de)
In conclusion, vitrification by direct submerging of oocytes in clean liquid air (aseptic system) is a good alternative for using of not sterile liquid nitrogen. (uni-koeln.de)

In fertility, that would be the oocyte. (pinkstork.com)

Oocyte-granulosa cell complexes were cultured for 14 days in modified TCM199 medium supplemented with 5% fetal bovine serum, 4 mM hypoxanthine, and 0.1 μg/ml estradiol. (bioone.org)

SO2: investigate whether the pattern of translation is disrupted in oocyte from aging mice. (europa.eu)

Oocyte identity is established inside a cyst of interconnected germ cells but how this occurs is not well understood. (cam.ac.uk)
The microtubule minus end-binding protein Patronin/CAMSAP translates the asymmetry into a polarised microtubule network that directs transport of oocyte fate determinants into a single germ cell to establish the oocyte. (cam.ac.uk)

RNAi knockdown of CAR-1 in nematodes increases oocyte apoptosis, as does CGH-1 depletion. (biologists.com)

Then the zona pellucida free follicular oocytes in extraction solution were frozen in LN_2, thawed and centrifuged and the G6PDH activity of their supernatant could be measured. (nii.ac.jp)

Study of post-transcriptional regulatory pathways revealed that the small-RNA mediated regulatory pathways exist in a unique conformation in mouse oocytes. (cuni.cz)

My PhD project was aimed at understanding the constraints of the miRNA pathway in the oocyte which makes it non-functional. (cuni.cz)

In study 1 we showed that diet induced obesity caused increased pro-inflammatory signaling in the ovary including in growing oocytes. (unl.edu)
We particularly suggest selecting the ovary with a low antral follicle count for wedge resection to increase oocyte yield. (ijfs.ir)

Given the genome-wide transcriptional silencing, mRNA expression studies in MII oocytes should only yield stable mRNA or decreased mRNA due to degradation. (europa.eu)

One straw can be used to fertilize 3-5 dishes of oocytes which maximizes the yield of expensive semen. (bova-tech.com)
We suggest that this approach can increase the oocyte yield in a single available COH cycle. (ijfs.ir)

Primary oocytes are diploid cells generated before birth. (copewithcytokines.de)
Oocytes play an active role in this cooperativity by secreting factors that act on the supporting cells in a paracrine manner (Sugiura and Eppig, 2005). (copewithcytokines.de)
The interplay of signals arising in both follicle cells and oocytes themselves (1 2 4 6 7 regulates synthesis and degradation of oocyte cAMP via adenylyl cyclases and cyclic nucleotide phosphodiesterases (PDEs) respectively. (immune-source.com)
The effect of follicular aging on gene expression in oocytes and granulosal cells. (wvu.edu)
It is suggested that aged granulosal cells may have a reduced capacity to provide energy and amino acids to the oocyte. (wvu.edu)
They selected females that had just molted into adulthood, and anesthetized them to remove some of their oocytes, or developing egg cells. (smithsonianmag.com)

An experiment was done to determine if persistence of a follicle altered mRNA expression of important genes in the oocyte. (wvu.edu)

Reproductive activity was assessed using macroscopic gonad characteristics, trends of gonadal indexes for both sexes, oocyte size-frequency distributions and microscopic investigation of oocyte development stages. (ifremer.fr)

These data demonstrate the sensitivity of mouse maturing oocytes in vivo to maternal protein undernutrition and identify both behavioural and cardiovascular postnatal outcomes, indicative of adult disease. (aston.ac.uk)
In this study, we determined that the expression of sirtuin family members (SIRT1, 2, 3) was dramatically reduced in mouse oocytes aged in vivo or in vitro. (scite.ai)

iv) BPA-exposed oocytes had higher rates of early stage apoptosis/autophagy, and this may be resulted from the increased level of oxidative stress. (oncotarget.com)

Early in oogenesis, dynein mutations disrupt spindle orientation in dividing cysts and block oocyte determination. (biologists.com)
This forms a polarized MT network, along which Dynein transports oocyte determinants into the presumptive oocyte. (cam.ac.uk)

Frog oocytes synthesize and completely process the precursor polypeptide to virion structural proteins after microinjection of avian myeloblastosis virus RNA. (duke.edu)

Oocyte donor information - how much is enough? (lancs.ac.uk)

Anatomy37

Organisms18

Diseases8

Chemicals and Drugs77

Analytical, Diagnostic and Therapeutic Techniques and Equipment38

Psychiatry and Psychology1

Phenomena and Processes64

Disciplines and Occupations2

Technology, Industry, Agriculture2

Information Science4

Health Care2

Bcl-2 regulates amplification of caspase activation by cytochrome c. (1/15764)

The mitogen-activated protein kinase signaling pathway stimulates mos mRNA cytoplasmic polyadenylation during Xenopus oocyte maturation. (2/15764)

Molecular dynamics of the sodium channel pore vary with gating: interactions between P-segment motions and inactivation. (3/15764)

The role of oocyte transcription, the 5'UTR, and translation repression and derepression in Drosophila gurken mRNA and protein localization. (4/15764)

KCNQ4, a novel potassium channel expressed in sensory outer hair cells, is mutated in dominant deafness. (5/15764)

Differential transcriptional activity associated with chromatin configuration in fully grown mouse germinal vesicle oocytes. (6/15764)

Ontogeny of expression of a receptor for platelet-activating factor in mouse preimplantation embryos and the effects of fertilization and culture in vitro on its expression. (7/15764)

An intact sperm nuclear matrix may be necessary for the mouse paternal genome to participate in embryonic development. (8/15764)

Oocytes

Oogenesis

Oocyte Donation

Oocyte Retrieval

Xenopus laevis

Meiosis

In Vitro Oocyte Maturation Techniques

Xenopus

Microinjections

Fertilization

Metaphase

Cumulus Cells

Parthenogenesis

Blastocyst

Ovum

Sperm-Ovum Interactions

Cryopreservation

Ovary

Sperm Injections, Intracytoplasmic

Embryonic Development

Embryo Transfer

Zona Pellucida

Maturation-Promoting Factor

Spermatozoa

Zygote

Cleavage Stage, Ovum

Embryo Culture Techniques

RNA, Complementary

Pregnancy

Egg Proteins

Nuclear Transfer Techniques

Follicular Fluid

Ovulation Induction

Cytoplasm

Proto-Oncogene Proteins c-mos

Cryoprotective Agents

Vitrification

Cell Nucleus

Polar Bodies

Embryo, Mammalian

RNA, Messenger

Embryonic and Fetal Development

Pregnancy Rate

Infertility, Female

Chorionic Gonadotropin

Molecular Sequence Data

Ovulation

Granulosa Cells

Cells, Cultured

Xenopus Proteins

Cattle

Morula

Progesterone

Meiotic Prophase I

Reproductive Techniques, Assisted

Spindle Apparatus

Chromosomes

Ethylene Glycol

Amino Acid Sequence

Vitellogenesis

Swine

Genes, mos

Prophase

Base Sequence

Gonadotropins

Superovulation

Growth Differentiation Factor 9

Blastomeres

Bone Morphogenetic Protein 15

Gene Expression Regulation, Developmental

CDC2 Protein Kinase

Time Factors

Sperm Head

Aneuploidy

Cloning, Molecular

Microtubules

Culture Media

Reproductive Techniques

Embryo Implantation

Membrane Potentials