Sample records for hamster oocyte penetration

  1. Effect of urea and detergents on the ability of human spermatozoa to penetrate zona-free hamster oocytes.

    PubMed

    Rosselli, M; Roatti, A; Marchini, M; Campana, A; Balerna, M

    1987-01-01

    Washing of human spermatozoa with either BWW alone or with the same buffer containing 0.1 M urea, 0.005% SDS or 0.001% NP40 affected the penetration ability of the gametes into zona-free hamster oocytes to various degrees. In contrast, human spermatozoa washed with BWW buffer containing 0.3 M urea had an increased ability to fuse with the heterologous oocytes when compared to controls capacitated with BWW/BSA. Moreover, the presence or absence of BSA in the insemination medium did not further modify this enhanced penetration pattern. The BWW, BWW/0.1 M urea and BWW/SDS treatments apparently mimicked some of the in vitro capacitation properties of albumin-containing media; the BWW/0.3 M urea treatment overpowered the capacitation and acrosomal reaction extent obtained with BWW+BSA. In all samples the motility of the spermatozoa washed with BWW buffer alone or containing various additives (but no albumin) was significantly decreased if compared to the motility of semen samples washed with albumin containing media. However, each sperm sample behaved differently when exposed to a given buffer. PMID:3425961

  2. An alternative medicine study of herbal effects on the penetration of zona-free hamster oocytes and the integrity of sperm deoxyribonucleic acid

    Microsoft Academic Search

    Richard R. Ondrizek; Philip J. Chan; William C. Patton; Alan King

    1999-01-01

    Objective: To analyze the effects of certain herbs on sperm DNA and on the fertilization process.Design: Prospective comparative study.Setting: Clinical and academic research environment.Patient(s): Donor sperm specimens.Intervention(s): Zona-free hamster oocytes were incubated for 1 hour in saw palmetto (Serenoa repens), echinacea purpura, ginkgo biloba, St. John’s wort (Hypericum perforatum), or control medium before sperm-oocyte interaction. The DNA of herb-treated sperm

  3. Thermostability of sperm nuclei assessed by microinjection into hamster oocytes

    EPA Science Inventory

    Nuclei isolated from spermatozoa of various species (golden hamster, mouse, human, rooster, and the fish tilapia) were heated at 60 degrees-125 degrees C for 20-120 min and then microinjected into hamster oocytes to determine whether they could decondense and develop into pronucl...

  4. THERMOSTABILITY OF SPERM NUCLEI ASSESSED BY MICROINJECTION INTO HAMSTER OOCYTES

    EPA Science Inventory

    Nuclei isolated from spermatozoa of various species (golden hamster, mouse, human, rooster, and the fish tilapia) were heated at 60 degrees - 125 degrees for 20-120 min and then microinjected into hamster oocytes to determine whether they could decondense and develop into pronucl...

  5. Role of the follicle in zona pellucida maturation of hamster oocyte

    E-print Network

    Paris-Sud XI, Université de

    Role of the follicle in zona pellucida maturation of hamster oocyte Jacqueline MANDELBAUM Michèle. Hamster oocytes matured in vitro are not fer- tilizable (Mandelbaum and Plachot, 1977). When immature). In this report, we re-investigate hamster oocyte maturation, comparing extra- and intrafollicular maturations

  6. DNA (DEOXYRIBONUCLEIC ACID) SYNTHESIS FOLLOWING MICROINJECTION OF HETEROLOGOUS SPERM AND SOMATIC CELL NUCLEI INTO HAMSTER OOCYTES

    EPA Science Inventory

    The authors have investigated the ability of the hamster oocyte to initiate DNA synthesis in nuclei differing in basic protein content. DNA synthesis was studied by autoradiography in oocytes that had been incubated in 3H-thymidine after being parthenogenetically activated by sha...

  7. Establishment of the block against sperm penetration in parthenogenetically activated bovine oocytes matured in vitro.

    PubMed

    Soloy, E; Srsen, V; Pavlok, A; Hyttel, P; Thomsen, P D; Smith, S D; Procházka, R; Kubelka, M; Høier, R; Booth, P; Motlík, J; Greve, T

    1997-09-01

    The ability of a single electric pulse to mimic a block against sperm penetration in bovine oocytes matured in vitro was investigated. Confocal laser scanning microscopy detected a global loss of spots, presumed to be cortical granules, stained with Lens culinaris agglutinin, in pulsed oocytes. Transmission electron microscopy revealed that cortical granule exocytosis occurred within 1 min of stimulation and the number of remaining cortical granules was significantly reduced in all pulsed oocytes. The ability of pulsed oocytes to undergo fertilization in vitro was also affected, as only 31% of the pulsed oocytes were penetrated compared with 87% in the control group. Since incidences of penetration in pulsed oocytes (31%), and of polyspermy in control oocytes (18%) did not differ and were highly correlated (P = 0.009) among trials (n = 15), the induced block is considered to be comparable with the natural block triggered by a spermatozoon. The increased resistance of the zona pellucida to pronase E observed in pulsed oocytes suggests that the induced block depends, at least partly, on modifications of zona pellucida glycoproteins. Finally, the majority (66%) of pulsed, penetrated oocytes did not form male pronuclei, probably as a consequence of asynchrony between the formation of female pronucleus and sperm penetration. The reduced ability of the cytoplasm to induce the formation of a male pronucleus was accompanied by a fall in histone H1 kinase activity to basal values by 3 h after stimulation. These results demonstrate that a single electric pulse can induce a block against sperm penetration similar to that of the spermatozoon itself. PMID:9370979

  8. CARBENDAZIM (MBC) DISRUPTS OOCYTE SPINDLE FUNCTION AND INDUCES ANEUPLOIDY IN HAMSTERS EXPOSED DURING FERTILIZATION (MEIOSIS II)

    EPA Science Inventory

    Peri-fertilization exposure to Carbendazim (MBC; a microtubule poison) induces infertility and early pregnancy loss (EPL) in hamsters. resently, both in vivo and in vitro techniques were employed to characterize the effects of MBC on cellular aspects of fertilization in hamsters....

  9. IMPORTANCE OF GLUTATHIONE IN THE ACQUISITION AND MAINTENANCE OF SPERM NUCLEAR DECONDENSING ACTIVITY IN MATURING HAMSTER OOCYTES

    EPA Science Inventory

    Sperm nuclear decondensing activity in mammalian oocytes is dependent upon the maturational state of the oocyte. It is maximal in mature, metaphase II oocytes and minimal or absent in immature germinal vesicle (GV) and fertilized pronuclear oocytes. Previous studies suggested tha...

  10. Free Ca2+ increases in exponential phases during mouse oocyte activation

    Microsoft Academic Search

    K. S. Roy Cuthbertson; D. G. Whittingham; Peter H. Cobbold

    1981-01-01

    A dramatic rise in cytoplasmic free Ca2+ concentration has been shown to occur during fertilization and artificial activation in the oocytes of both the medaka fish1 and sea urchin2. Indirect evidence has implicated Ca2+ in the parthenogenetic activation of mammalian oocytes. Mouse oocytes can be activated by the intracellular injection of Ca2+ but not Mg2+ (ref. 3), and hamster oocytes

  11. Sperm attachment and penetration competence in the human oocyte: a possible aetiology of fertilization failure involving the organization of oolemmal lipid raft microdomains influenced by the ??m of subplasmalemmal mitochondria.

    PubMed

    Van Blerkom, Jonathan; Caltrider, Kyle

    2013-12-01

    The roles of oolemmal lipid raft microdomains enriched in the ganglioside GM1 and the tetraspanin protein CD9 were investigated as causative agents in fertilization failure in human IVF where spermatozoa progress to the oolemma but fail to attach or, if attached, to penetrate. The findings show that specific configurations of GM1 lipid raft microdomains are consistent with attachment and penetration, while microdomains composed of CD9 lipid rafts, a protein known to be critical for penetration, do not appear to have a central role in the initial stages of attachment. The relative magnitude of the potential difference across the inner membrane (??m) in mitochondria localized to a stable subplasmalemmal domain appears to influence the organization of GM1 but not CD9 lipid raft microdomains in the corresponding oolemma. The findings present a novel view of how fertilization competence may be established in the human oocyte and a means by which certain fertilization failures that occur after conventional clinical IVF can be identified and explained in the unfortunate instance of fertilization arrest at the oolemma. PMID:24157131

  12. In vivo fertility of rams in relation to sperm-zona pellucida binding and sperm-zona pellucida penetration of ovine oocytes.

    PubMed

    Codde, J M; Berger, T

    1995-10-15

    Sperm-zona pellucida (zona) binding and sperm-zona penetration have been suggested for use as in vitro bioassays of fertility since both are essential steps in the fertilization process. The correlations of sperm-zona binding and sperm-zona penetration with the in vivo fertility of sheep were investigated in this study. In vivo fertility was estimated from a heterospermic insemination trial using cryopreserved ram semen. Neither zona binding, zona penetration nor the ability to undergo an acrosome reaction was significantly correlated with the in vivo fertility of the rams (P = 0.78, P = 0.66, and P = 0.85, respectively). These results suggest that the zona binding and zona penetration bioassays may not be useful estimators for assessing cryopreserved ram sperm fertility. PMID:16727785

  13. In vivo fertility of rams in relation to sperm-zona pellucida binding and sperm-zona pellucida penetration of ovine oocytes

    Microsoft Academic Search

    J. M. Codde; T. Berger

    1995-01-01

    Sperm-zona pellucida (zona) binding and sperm-zona penetration have been suggested for use as in vitro bioassays of fertility since both are essential steps in the fertilization process. The correlations of sperm-zona binding and sperm-zona penetration with the in vivo fertility of sheep were investigated in this study. In vivo fertility was estimated from a heterospermic insemination trial using cryopreserved ram

  14. Cryopreservation of starfish oocytes.

    PubMed

    Hamarato?lu, Fisun; Ero?lu, Ali; Toner, Mehmet; Sadler, Kirsten C

    2005-02-01

    Research from many laboratories over the past several decades indicates that invertebrate oocytes and eggs are extraordinarily difficult to freeze. Since starfish oocytes, eggs, and embryos are an important cell and developmental biology model system, there is great interest to cryopreserve these cells. Previous starfish oocyte cryopreservation studies using slow cooling protocols revealed that these cells are highly sensitive to osmotic stress and form intracellular ice at very high sub-zero temperatures, suggesting that common freezing methodologies may not prove useful. We report here that a short exposure to 1.5 M Me2SO/1 M trehalose in hypotonic salt solution followed by ultra-rapid cooling to cryogenic temperatures allows starfish oocytes to be cryopreserved with the average survival rate of 34% when normalized to control oocytes that were exposed to CPA, but not frozen. On average, 51% of the oocytes in 77% of the batches of frozen oocytes underwent meiotic maturation in response to the starfish maturation hormone, 1-methyladenine. In one experiment, eggs developing from thawed oocytes were capable of being fertilized and two developed into embryos. These data suggests that successful cryopreservation of starfish oocytes is possible, but will need further refinement to increase the numbers of fully competent embryos. PMID:15710368

  15. [Mitochondrial and oocyte development].

    PubMed

    Deng, Wei-Ping; Ren, Zhao-Rui

    2007-12-01

    Oocyte development and maturation is a complicated process. The nuclear maturation and cytoplasmic maturation must synchronize which can ensure normal oocyte fertilization and following development. Mitochondrial is the most important cellular organell in cytoplasm, and the variation of its distribution during oocyte maturation, the capacity of OXPHOS generating ATP as well as the content or copy number or transcription level of mitochondrial DNA play an important role in oocyte development and maturation. Therefore, the studies on the variation of mitochondrial distribution, function and mitochondrial DNA could enhance our understanding of the physiology of reproduction and provide new insight to solve the difficulties of assisted reproduction as well as cloning embryo technology. PMID:18065375

  16. Original article Mouse oocyte maturation

    E-print Network

    Paris-Sud XI, Université de

    Original article Mouse oocyte maturation: the effect of modified nucleocytoplasmic ratio Lenka oocytes isolated from large antral follicles and cultured in vitro complete their maturation up maturation gradually decreases. In the half oocytes, 66 % (33/50) extruded 1PB, while in third oocytes

  17. Germ cell-specific localization of immunoreactive riboflavin carrier protein in the male golden hamster: appearance during spermatogenesis and role in sperm function.

    PubMed

    Sreekumar, A; Acharya, K K; Lalitha, H S; Indi, S S; Bali, P; Seshagiri, P B

    2005-05-01

    Riboflavin carrier protein (RCP) is a phosphoglycoprotein (37 kDa) that is well studied in chicken. An immunologically cross-reacting protein was identified in mammals and active immunization of male rats and bonnet monkeys with chicken RCP lead to an approximately 80% reduction in fertility. However, the physiological mechanism responsible for inhibition of male fertility has not been investigated. Moreover, information on the cell type-specific localization and the origin of immunoreactive RCP during spermatogenesis is extremely limited. Hence, studies were carried out to determine the pattern of expression of immunoreactive RCP during spermatogenesis and its role in sperm function in the golden hamster. Immunoreactive RCP was germ cell-specific, found to be associated with the acrosome-organizing region of early spermatids and showed interesting patterns of immunolocalization during late stages of spermiogenesis. Mature spermatozoa exhibited acrosome-specific localization, mainly in the peri-acrosomal membrane. The immunoreactive protein was undetectable in (non)gonadal somatic cells tested. The protein had a molecular mass of 45-55 kDa and was biosynthesized by round spermatids. The acrosome-specific localization of immunoreactive RCP was unchanged during capacitation, but it was substantially lost during acrosome reaction. Functional studies indicated that treatment of spermatozoa with anti-RCP antibodies did not have any effect on either capacitation or acrosome reaction, but markedly reduced the rate of sperm penetration into zona-free hamster oocytes. These results show the existence of male germ cell-specific immunoreactive RCP, having a potential role in sperm-egg interaction in hamsters. Also the pattern of immunoreactive-RCP localization makes it an ideal marker to monitor development of acrosome in mammalian spermatozoa. PMID:15855621

  18. Assessment of the genotoxicity of three cryoprotectants used for human oocyte vitrification: Dimethyl sulfoxide, ethylene glycol and propylene glycol

    Microsoft Academic Search

    M. Aye; C. Di Giorgio; M. De Mo; A. Botta; J. Perrin; B. Courbiere

    2010-01-01

    Vitrification requires high concentrations of cryoprotectants that may induce long-term toxic effects on cells. The aim of this study was to evaluate the possible genotoxicity of three cryoprotectants extensively used for oocyte vitrification: dimethyl sulfoxide (DMSO), ethylene glycol (EG) and propylene glycol (PROH). For this purpose, a Chinese Hamster Ovary cell line (CHO), commonly used in genetic toxicology, was selected

  19. Oocyte ageing and epigenetics

    PubMed Central

    Ge, Zhao-Jia; Schatten, Heide; Zhang, Cui-Lian; Sun, Qing-Yuan

    2015-01-01

    It has become a current social trend for women to delay childbearing. However, the quality of oocytes from older females is compromised and the pregnancy rate of older women is lower. With the increased rate of delayed childbearing, it is becoming more and more crucial to understand the mechanisms underlying the compromised quality of oocytes from older women, including mitochondrial dysfunctions, aneuploidy and epigenetic changes. Establishing proper epigenetic modifications during oogenesis and early embryo development is an important aspect in reproduction. The reprogramming process may be influenced by external and internal factors that result in improper epigenetic changes in germ cells. Furthermore, germ cell epigenetic changes might be inherited by the next generations. In this review, we briefly summarise the effects of ageing on oocyte quality. We focus on discussing the relationship between ageing and epigenetic modifications, highlighting the epigenetic changes in oocytes from advanced-age females and in post-ovulatory aged oocytes as well as the possible underlying mechanisms. PMID:25391845

  20. Single Oocyte Bisulfite Mutagenesis

    PubMed Central

    Denomme, Michelle M.; Zhang, Liyue; Mann, Mellissa R.W.

    2012-01-01

    Epigenetics encompasses all heritable and reversible modifications to chromatin that alter gene accessibility, and thus are the primary mechanisms for regulating gene transcription1. DNA methylation is an epigenetic modification that acts predominantly as a repressive mark. Through the covalent addition of a methyl group onto cytosines in CpG dinucleotides, it can recruit additional repressive proteins and histone modifications to initiate processes involved in condensing chromatin and silencing genes2. DNA methylation is essential for normal development as it plays a critical role in developmental programming, cell differentiation, repression of retroviral elements, X-chromosome inactivation and genomic imprinting. One of the most powerful methods for DNA methylation analysis is bisulfite mutagenesis. Sodium bisulfite is a DNA mutagen that deaminates cytosines into uracils. Following PCR amplification and sequencing, these conversion events are detected as thymines. Methylated cytosines are protected from deamination and thus remain as cytosines, enabling identification of DNA methylation at the individual nucleotide level3. Development of the bisulfite mutagenesis assay has advanced from those originally reported4-6 towards ones that are more sensitive and reproducible7. One key advancement was embedding smaller amounts of DNA in an agarose bead, thereby protecting DNA from the harsh bisulfite treatment8. This enabled methylation analysis to be performed on pools of oocytes and blastocyst-stage embryos9. The most sophisticated bisulfite mutagenesis protocol to date is for individual blastocyst-stage embryos10. However, since blastocysts have on average 64 cells (containing 120-720 pg of genomic DNA), this method is not efficacious for methylation studies on individual oocytes or cleavage-stage embryos. Taking clues from agarose embedding of minute DNA amounts including oocytes11, here we present a method whereby oocytes are directly embedded in an agarose and lysis solution bead immediately following retrieval and removal of the zona pellucida from the oocyte. This enables us to bypass the two main challenges of single oocyte bisulfite mutagenesis: protecting a minute amount of DNA from degradation, and subsequent loss during the numerous protocol steps. Importantly, as data are obtained from single oocytes, the issue of PCR bias within pools is eliminated. Furthermore, inadvertent cumulus cell contamination is detectable by this method since any sample with more than one methylation pattern may be excluded from analysis12. This protocol provides an improved method for successful and reproducible analyses of DNA methylation at the single-cell level and is ideally suited for individual oocytes as well as cleavage-stage embryos. PMID:22782232

  1. Fertilization ability of porcine oocytes reconstructed from ooplasmic fragments produced and characterized after serial centrifugations.

    PubMed

    Viet Linh, Nguyen; Kikuchi, Kazuhiro; Nakai, Michiko; Tanihara, Fuminori; Noguchi, Junko; Kaneko, Hiroyuki; Dang-Nguyen, Thanh Quang; Men, Nguyen Thi; Van Hanh, Nguyen; Somfai, Tamas; Nguyen, Bui Xuan; Nagai, Takashi; Manabe, Noboru

    2013-12-17

    Mitochondria are reported to be critical in in vitro maturation of oocytes and subsequent embryo development after fertilization, but their contribution for fertilization has not been investigated in detail. In the present study, we investigate the contribution of mitochondria to fertilization using reconstructed porcine oocytes by fusion of ooplasmic fragments produced by serial centrifugations (centri-fusion). Firstly, we evaluated the characteristics of ooplasmic fragments. Three types of fragments were obtained by centrifugation of porcine oocytes matured in vitro for 46 h: brownish (B), transparent (T) and large (L) fragments containing both B and T parts in a fragment. The production efficiencies of these types of fragments were 71.7, 91.0 and 17.8 fragments/100 oocytes, respectively. In experiments, L fragments were excluded because they contained both brownish and transparent components that were apparently intermediate between B and T fragments. Observations by confocal microscopy after staining with MitoTracker Red CMXRos® and transmission electron microscopy revealed highly condensed active mitochondria in B fragments in contrast to T fragments that contained only sparse organelles. We reconstructed oocytes by fusion of a karyoplast and two cytoplasts from B and T fragments (B and T oocytes, respectively). The B oocytes showed higher sperm penetration (95.8%) and male pronuclear formation rates (94.2%) by in vitro fertilization than T oocytes (66.7% and 50.0%, respectively). These results suggest that the active mitochondria in oocytes may be related to their ability for fertilization. PMID:23965685

  2. Curiosity in the hamster

    Microsoft Academic Search

    Gerald E. Schneider; Charles G. Gross

    1965-01-01

    Running time for repeated alley runs by hamsters to end boxes containing (a) nothing, (b) a constant set of objects, or (c) a changing set of objects was in the order a > b > c: thus, novelty appeared reinforcing. Length of intersession interval (2, 24, 48 hr.) affected only Condition b: thus, \\

  3. Clinical benefit of metaphase I oocytes

    Microsoft Academic Search

    Leen Vanhoutte; Petra De Sutter; Josiane Van der Elst; Marc Dhont

    2005-01-01

    BACKGROUND: We studied the benefit of using in vitro matured metaphase I (MI) oocytes for ICSI in patients with a maximum of 6 mature metaphase II (MII) oocytes at retrieval. METHODS: In 2004, 187 ICSI cycles were selected in which maximum 6 MII oocytes and at least one MI oocyte were retrieved. MI oocytes were put in culture to mature

  4. The effect of sera, bovine serum albumin and follicular cells on in vitro maturation and fertilization of porcine oocytes.

    PubMed

    Zheng, Y S; Sirard, M A

    1992-04-01

    The effects of fetal calf serum (FCS), estrus gilt serum (EGS) BSA, dispersed granulosa cells, hemi-sections of follicular wall, and replacement of medium after 24 hours on in vitro maturation and fertilization of porcine oocytes were studied. The results indicate that the use of BSA for 24 or 48 hours inhibited the expansion of cumulus cells and the maturation of oocytes. An incubation of 24 hours culture in FCS followed by a second 24 hours in BSA containing medium did not decrease the rate of maturation but significantly decreased the polyspermy and mean number of spermatozoa penetrated/oocyte. Renewing the medium with or without removal of cumulus cells during the second incubation increased the maturation rate. Removal of cumulus cells decreased the penetrability, the polyspermy rates of the oocyte and the mean number of spermatozoa/oocyte penetrated. The EGS-supplemented medium, dispersed granulosa cells or hemi-sections of follicular wall did not affect the maturation or fertilization rates. In conclusion, BSA, a protein supplement in maturation medium, inhibited cumulus cell expansion and maturation of porcine oocytes. After resumption of meiosis triggered by FCS, BSA did not influence maturation. The FCS-BSA treatment reduced the incidence of polyspermy and the mean number of spermatozoa penetrated/oocyte without decreasing the rate of maturation and fertilization. PMID:16727079

  5. Development block of golden hamster ICSI embryos is associated with decreased expression of HDAC1, HSPA1A and MYC.

    PubMed

    Pan, Xiaoyan; Kong, Delong; Liu, Limei; Gao, Fei; Zhang, Xueming; Tang, Bo; Li, Ziyi

    2014-11-01

    We have investigated the mechanism for embryo development block in vitro and to improve the development rate of golden hamster embryos in vitro. Intracytoplasmic sperm injection (ICSI) technique was used to produce golden hamster ICSI embryos. The changes in the histone acetylation and the expression of histone deacetylase and related genes were analyzed by immunocytochemical staining and real-time PCR both in golden hamster in vivo embryos and in ICSI embryos. Aged oocytes significantly increased the oocyte spontaneous activation rate. In vitro cultured ICSI embryos suffered from severe development block in M199TE medium. Expression of histone deacetylase 1 (HDAC1) was significantly decreased in the nuclei of the arrested ICSI 2-cell embryos, and its nuclear and cytoplasmic expression pattern was also markedly altered. The acetylation level of H4K5, however, was not significantly changed between golden hamster in vivo embryos and ICSI embryos. HSPA1A and MYC, the marker genes for zygotic genome activation (ZGA), were transcriptionally decreased in arrested ICSI 2-cell embryos. Transcription of HDAC1 was also downregulated in these embryos, whereas the mRNA expression of the proapoptotic gene, BAX, was not changed. These results indicate that the golden hamster ICSI embryo development block during ZGA is associated with decreased nuclear expression and altered expression of HDAC1. HSPA1A, MYC, and HDAC1 mRNA levels, which decrease, resulting in ZGA failure. PMID:24890342

  6. Photoperiodic Control of Hamster Testis

    Microsoft Academic Search

    Suzanne Gaston; Michael Menaker

    1967-01-01

    The response of the testes of juvenile and adult hamsters to various photoperiods was examined. The testes of juvenile animals reached maturity regardless of the light cycle on which the animals were raised. However, the testes of adult hamsters required at least 12.5 hours of light per day to maintain spermatogenesis and prevent degeneration. This is one of the few

  7. Microinjection of follicle-enclosed mouse oocytes

    PubMed Central

    Jaffe, Laurinda A.; Norris, Rachael P.; Freudzon, Marina; Ratzan, William J.; Mehlmann, Lisa M.

    2011-01-01

    Summary The mammalian oocyte develops within a complex of somatic cells known as a follicle, within which signals from the somatic cells regulate the oocyte, and signals from the oocyte regulate the somatic cells. Because isolation of the oocyte from the follicle disrupts these communication pathways, oocyte physiology is best studied within an intact follicle. Here we describe methods for quantitative microinjection of follicle-enclosed mouse oocytes, thus allowing the introduction of signaling molecules as well as optical probes into the oocyte within its physiological environment. PMID:19085139

  8. Penetration enhancers

    Microsoft Academic Search

    Adrian C Williams; Brian W Barry

    2004-01-01

    One long-standing approach for improving transdermal drug delivery uses penetration enhancers (also called sorption promoters or accelerants) which penetrate into skin to reversibly decrease the barrier resistance. Numerous compounds have been evaluated for penetration enhancing activity, including sulphoxides (such as dimethylsulphoxide, DMSO), Azones (e.g. laurocapram), pyrrolidones (for example 2-pyrrolidone, 2P), alcohols and alkanols (ethanol, or decanol), glycols (for example propylene

  9. Validation of a heterologous fertilization assay and comparison of fertilization rates of equine oocytes using in vitro fertilization, perivitelline, and intracytoplasmic sperm injections.

    PubMed

    Sessions-Bresnahan, D R; Graham, J K; Carnevale, E M

    2014-07-15

    IVF in horses is rarely successful. One reason for this could be the failure of sperm to fully capacitate or exhibit hyperactive motility. We hypothesized that the zona pellucida (ZP) of equine oocytes prevents fertilization in vitro, and bypassing the ZP would increase fertilization rates. Limited availability of equine oocytes for research has necessitated the use of heterologous oocyte binding assays using bovine oocytes. We sought to validate an assay using bovine oocytes and equine sperm and then to demonstrate that bypassing the ZP using perivitelline sperm injections (PVIs) with equine sperm capacitated with dilauroyl phosphatidylcholine would result in higher fertilization rates than standard IVF in bovine and equine oocytes. In experiment 1, bovine oocytes were used for (1) IVF with bovine sperm, (2) IVF with equine sperm, and (3) intracytoplasmic sperm injections (ICSIs) with equine sperm. Presumptive zygotes were either stained with 4',6-diamidino-2-phenylindole from 18 to 26 hours at 2-hour intervals or evaluated for cleavage at 56 hours after addition of sperm. Equine sperm fertilized bovine oocytes; however, pronuclei formation was delayed compared with bovine sperm after IVF. The delayed pronuclear formation was not seen after ICSI. In experiment 2, bovine oocytes were assigned to the following five groups: (1) cumulus oocyte complexes (COCs) coincubated with bovine sperm; (2) COC exposed to sucrose then coincubated with bovine sperm; (3) COC coincubated with equine sperm; (4) COC exposed to sucrose, and coincubated with equine sperm; and (5) oocytes exposed to sucrose, and 10 to 15 equine sperm injected into the perivitelline (PV) space. Equine sperm tended (P = 0.08) to fertilize more bovine oocytes when injected into the PV space than after IVF. In experiment 3, oocytes were assigned to the following four groups: (1) IVF, equine, and bovine COC coincubated with equine sperm; (2) PVI of equine and bovine oocytes; (3) PVI with equine oocytes pretreated with sucrose; and (4) ICSI of equine oocytes. Oocytes were examined at 24 hours for cleavage. No equine oocytes cleaved after IVF or PVI. However, ICSI conducted with equine sperm treated with dilauroyl phosphatidylcholine resulted in 85% of the oocytes cleaving. Sperm injected into the PV space of equine oocytes did not appear to enter the ooplasm. This study validated the use of bovine oocytes for equine sperm studies and indicates that failure of equine IVF is more than an inability of equine sperm to penetrate the ZP. PMID:24815920

  10. Penetration equations

    SciTech Connect

    Young, C.W. [Applied Research Associates, Inc., Albuquerque, NM (United States)

    1997-10-01

    In 1967, Sandia National Laboratories published empirical equations to predict penetration into natural earth materials and concrete. Since that time there have been several small changes to the basic equations, and several more additions to the overall technique for predicting penetration into soil, rock, concrete, ice, and frozen soil. The most recent update to the equations was published in 1988, and since that time there have been changes in the equations to better match the expanding data base, especially in concrete penetration. This is a standalone report documenting the latest version of the Young/Sandia penetration equations and related analytical techniques to predict penetration into natural earth materials and concrete. 11 refs., 6 tabs.

  11. Oocyte cryopreservation: oocyte assessment and strategies for improving survival.

    PubMed

    Ledda, Sergio; Bogliolo, Luisa; Succu, Sara; Ariu, Federica; Bebbere, Daniela; Leoni, Giovanni Giuseppe; Naitana, Salvatore

    2007-01-01

    Despite significant progress in cryopreservation of mammalian oocytes and embryos, many ofthe molecular and biochemical events that underlie this technology are poorly understood. In recent years, researchers have focused on obtaining viable oocytes that are developmentally competent. Even under the most favourable conditions, experimental approaches have achieved only limited success compared with fresh oocytes used in routine in vitro embryo production. Chilling injuries and toxic effects of the cryoprotectants are the major adverse consequences following cryoprocedures. To overcome these problems, different strategies have been developed for improving cryopreservation results. These strategies include reducing container volumes, increasing the thermal gradient, changing the cell surface/volume ratio, enhancing cryotolerance by supplementation with various additives or modifying the lipid composition of the oocyte membrane. In order to develop new strategies for reducing the various forms of stress associated with oocyte cryopreservation, it is fundamental to gain a better understanding of the major changes responsible for poor post-thaw survival. With this knowledge, we hope that oocyte cryostorage will become a fully reliable reproductive technique in the near future. PMID:17389131

  12. The Transcriptome of a Human Polar Body Accurately Reflects Its Sibling Oocyte*S

    E-print Network

    Wessel, Gary M.

    The Transcriptome of a Human Polar Body Accurately Reflects Its Sibling Oocyte*S Received: Clinicians need additional metrics for predicting quality of human oocytes for IVF procedures. Results: Human and accurately eval- uate oocyte quality prior to fertilization and transfer into the woman of human embryos

  13. Fertilization and development of Caprine oocytes matured over granulosa cell monolayers.

    PubMed

    Teotia, A; Sharma, G T.; Majumdar, A C.

    2001-05-01

    The aim of the present study was to compare the two oocyte maturation systems, i.e. a granulosa cell (GC) monolayer from small (<4mm) or large (>4mm) follicles and a granulosa co-culture for their effects on in vitro maturation (IVM), fertilization and developmental competence of caprine oocytes. A total of 1945 oocytes were used for studies on maturation, fertilization and embryo development. Monolayers were primed with maturation medium, 18-24h before the onset of maturation. Nuclear studies of 263 fertilized oocytes, 18h post-fertilization, revealed that the rate of sperm penetration was not affected by any of the maturation culture systems. Penetration rate was 66.30% versus 69.59% for the control and GC monolayers. On the other hand, progression of fertilization, i.e. sperm head decondensation (32.70% versus 9.78%) and pronucleus formation (8.76% versus 2.17%) were significantly (P<0.05) enhanced in the oocytes matured over GC monolayers, compared to those with GC co-culture respectively. Cleavage rate was significantly (P<0.05) higher in the oocytes matured and cultured over GC monolayers (27.59%) compared to those in oocytes matured and cultured with the GC co-culture (19.28%). Proportionately more embryos derived from oocytes matured and cultured with the GC co-culture blocked (16.53 and 25.92%) at early developmental stages (2-cell and 4-cell, respectively), compared to those derived from oocytes matured and cultured over GC monolayers (7.61% versus 10.56%; 2-cell versus 4-cell). It was concluded that GC monolayers better support cytoplasmic maturation of growing caprine oocytes, which is evident by a better maturation rate, active fertilization, an improved cleavage rate and subsequently a higher rate of morula formation. Granulosa cells from small and large follicles can be used for IVM and IVC with approximately the same efficiency after conditioning them with maturation medium and embryo development medium 18-24h before the onset of culture. PMID:11295399

  14. Cold-induced changes in amphibian oocytes

    SciTech Connect

    Angelier, N.; Moreau, N.A.; N'Da, E.A.; Lautredou, N.F. (Centre de Biologie Cellulaire, Ivry-sur-Seine (France))

    1989-08-01

    Female Pleurodeles waltl newts (Amphibia, urodele), usually raised at 20 degrees C, were submitted to low temperatures; oocytes responded to this cold stress by drastic changes both in lampbrush chromosome structure and in protein pattern. Preexisting lateral loops of lampbrush chromosomes were reduced in size and number, while cold-induced loops which were tremendously developed, occurred on defined bivalents of the oocyte at constant, reproducible sites. A comparison of protein patterns in control and stressed oocytes showed two main differences: in stressed oocytes, overall protein synthesis was reduced, except for a set of polypeptides, the cold-stress proteins; second, there was a striking inversion of the relative amount of beta- and gamma-actin found in the oocyte nucleus before and after cold stress. Whereas beta-actin was the predominant form in control oocytes, gamma-actin became the major form in stressed oocytes.

  15. Comparison of in-vitro outcomes from cryopreserved oocytes and sibling fresh oocytes.

    PubMed

    Chamayou, S; Alecci, C; Ragolia, C; Storaci, G; Maglia, E; Russo, E; Guglielmino, A

    2006-06-01

    In Italy, the restrictive IVF law generalizes the indication for oocyte freezing for surplus oocytes in 78.5% of in-vitro assisted reproductive cycles. With a view to understanding better what the prospects for intracytoplasmic sperm injection (ICSI) on frozen-thawed oocytes might be, the consequences of freeze-thaw procedures on fertilization, cleavage rates and embryo quality obtained from frozen-thawed oocytes were studied and compared with the results obtained from sibling fresh oocytes. Eleven IVF and 29 ICSI on 76 and 169 fresh oocytes were performed and the corresponding 40 ICSI on 221 sibling frozen-thawed oocytes. There was no difference in terms of fertilization rate between fresh and sibling frozen-thawed oocytes. The cleavage rate (98.0 and 94.4% with fresh oocytes in IVF and ICSI; 77.3% with frozen-thawed oocytes in ICSI; P < 0.001) and embryo quality (grade I embryos over total embryos: 36.7 and 22.2% with fresh oocytes in IVF and ICSI; 12.1% with frozen-thawed oocytes in ICSI; respectively P < 0.001 and P < 0.05) were statistically lower after oocyte cryopreservation. The significant decrease in meiotic spindle retrieval rate before freezing (62.4%) and after thawing procedures (43.4%; P < 0.001) suggests that cryoconservation induces irreversible damage to microtubule repolymerization. The consequences of oocyte cryopreservation procedures on embryo development are reviewed. PMID:16792849

  16. Human oocyte maturation in vitro.

    PubMed

    Coticchio, Giovanni; Dal-Canto, Mariabeatrice; Guglielmo, Maria-Cristina; Mignini-Renzini, Mario; Fadini, Rubens

    2012-01-01

    Oocytes from medium-sized antral follicles have already completed their growth phase and, if released from the follicular environment and cultured in vitro, are able to resume the meiotic process and mature. However, in vitro maturation (IVM) does not entirely support all the nuclear and cytoplasmic changes that occur physiologically as an effect of the ovulatory stimulus. Regardless, oocyte IVM is widely applied for the breeding of agriculturally important species. In assisted reproduction technology, IVM has been proposed as an alternative treatment to circumvent the drawbacks of standard ovarian stimulation regimens. Initially introduced to eliminate the risks of ovarian hyperstimulation syndrome afflicting women presenting with polycystic ovaries, subsequently IVM has been suggested to represent an additional approach suitable also for normovulatory patients. So far, in children born from IVM cycles, no doubts of an increased incidence of congenital abnormalities have been raised. Many more births would be achieved if novel IVM systems, currently dominated by empiricism, could be conceived according to more physiological criteria. Recent findings shedding new light on the control of meiotic progression, the support of cumulus cells to the oocyte cellular reorganization occurring during maturation, and the modulation of the stimulus that promotes oocyte maturation downstream the mid-cycle gonadotropin signal are likely to provide crucial hints for the development of more efficient IVM systems. PMID:23417413

  17. High doses of medroxyprogesterone as the cause of disappearance of adherence of the zona pellucida to an oocyte

    PubMed Central

    J?drych, Marian; Matysiak, W?odzimierz

    2010-01-01

    The zona pellucida (ZP) is an external glycoprotein membrane of oocytes of mammals and embryos in the early stage of their development. ZP first appears in growing ovarian follicles as an extracellular substance between the oocyte and granular cells. The zona pellucid markedly affects the development and maturation of the oocyte. The morphology of the ZP-oocyte complex allows a more precise determination of the oocyte maturity. According to numerous experimental studies, ZP is essential for preimplantation embryonic development of humans and other mammals. It prevents dispersion of blastomeres and enhances their mutual interactions. ZP is a dynamic structure responsible for the provision of nutrients to early forms of oocytes in mammals. The aim of the present study was untrastructural evaluation of the ZP-oocyte contact during inhibited ovulation. Female white rats (Wistar strain) received a suspension of medroxyprogesterone acetate (MPA) in incremental intramuscular bolus doses of 3.7 mg (therapeutic dose), 7.4 mg and 11.1 mg. The animals were decapitated 5 days after the administration of MPA. Ovarian sections were evaluated under a transmission electron microscope (TEM) Zeiss EM 900. Morphometric analysis of ZP was conducted using the cell imaging system by Olympus. In females exposed to therapeutic doses of MPA, ZP showed the structure of granular-fibrous reticulum of a medium electron density with single cytoplasmic processes originating from the surrounding structures. The oocyte cell membrane generated single, delicate processes directed toward ZP. Microvilli of the oocyte were short and thin. In the group receiving 7.4 mg of MPA, ZP had the structure of a delicate, loose granular-fibrous reticulum, and the oocyte cell membrane generated single microvilli directed toward ZP. In both those groups, the close ZP-oocyte contact was observed. Otherwise, in the group exposed to the highest MPA doses (11.1 mg), thicker and more numerous oocyte microvilli were found, which did not penetrate ZP matrix. They were dense, irregularly separated contour, forming a barrier between ZP and oocyte. The present findings are likely to suggest that MPA has inhibiting effects on the synthesis of binding proteins and causes the loss of the oocyte contact with ZP. PMID:20714762

  18. Comparison of in-vitro outcomes from cryopreserved oocytes and sibling fresh oocytes

    Microsoft Academic Search

    S Chamayou; C Alecci; C Ragolia; G Storaci; E Maglia; E Russo; A Guglielmino

    2006-01-01

    In Italy, the restrictive IVF law generalizes the indication for oocyte freezing for surplus oocytes in 78.5% of in-vitro assisted reproductive cycles. With a view to understanding better what the prospects for intracytoplasmic sperm injection (ICSI) on frozen–thawed oocytes might be, the consequences of freeze–thaw procedures on fertilization, cleavage rates and embryo quality obtained from frozen–thawed oocytes were studied and

  19. Dynamic changes of estradiol and progesterone concentrations during in vitro oocyte maturation in cattle.

    PubMed

    Xu, K P; Høier, R; Greve, T

    1988-08-01

    Two culture techniques, an open system using 1.0-ml medium and a covered system using 50-mul droplets of medium covered by paraffin oil, used for in vitro bovine follicular oocyte maturation were compared. Estradiol-17beta (E2) was added to Ham's F-10 medium together with other supplementations. In the absence of oocytes, E2 concentration remained unchanged in the 1.0-ml open system, but it decreased gradually in the 50-mul covered system. In the presence of oocytes, E2 increased significantly in the 1.0-ml open system, but this increase could not be detected in the 50-mul covered system. Progesterone (P4) concentration increased in both systems, but it was much higher in the 1.0-ml culture than in the 50-mul culture. The two culture systems allowed an identical nuclear oocyte maturation rate of 88.6 vs 87.0%, a sperm penetration rate of 54.3 vs 59.6%, and a polyspermy rate of 6.8 vs 11.6% for 1.0-ml and 50-mul systems, respectively. The cleavage rate, however, differed significantly (78.3 vs 41.7% for 1.0-ml and 50-mul systems, respectively). It is concluded that diffusion of steroids into the paraffin oil occurs and may affect the cleavage rate but not the maturation or penetration rate. PMID:16726467

  20. Preference for bedding material in Syrian hamsters

    Microsoft Academic Search

    M Lanteigne; S G Reebs

    2006-01-01

    Summary This study aimed to determine whether Syrian (golden) hamsters, Mesocricetus auratus, prefer certain bedding materials and whether bedding material can affect paw condition, body weight gain and wheel-running activity. In a first experiment, 26 male hamsters had access to two connected cages, each cage containing a different bedding material (either pine shavings, aspen shavings, corn cob or wood pellets).

  1. FATE OF INHALED FLY ASH IN HAMSTERS

    EPA Science Inventory

    To determine pulmonary deposition, translocation, and clearance of inhaled fly ash, hamsters received a single 95-min nose-only exposure to neutron-activated fly ash. Over a period of 99 days postexposure, the hamsters were sacrificed in groups of six animals. Lungs, liver, kidne...

  2. Directed Student Inquiry: Modeling in Roborovsky Hamsters

    ERIC Educational Resources Information Center

    Elwess, Nancy L.; Bouchard, Adam

    2007-01-01

    In this inquiry-based activity, Roborovsky hamsters are used to provide students with an opportunity to develop their skills of analysis, inquiry, and design. These hamsters are easy to maintain, yet offer students a means to use conventional techniques and those of their own design to make further observations through measuring, assessing, and…

  3. Increased expression of ERp57 in rat oocytes during meiotic maturation is associated with sperm-egg fusion.

    PubMed

    Liu, Yue; Zhu, Yemin; Wu, Xiaohui; Li, Yandong; Guo, Qiangsu; Li, Weiping; Ding, Zhide

    2014-04-01

    Oocyte meiotic maturation is a developmental transition that starts during germinal-vesicle breakdown and ends at the arrest in metaphase of meiosis II. This transition is associated with changes to both the proteins that are synthesized and the abundance/distribution of post-translational modifications that are crucial for subsequent fertilization and embryogenesis. Here, we isolated and cultured rat oocytes in vitro during both metaphase of meiosis I (MI) and meiosis II (MII) stages, respectively, and then compared their proteomic profiles by high-resolution, two-dimensional gel electrophoresis (2DE) followed by mass spectrometry. We found that the expression of five proteins was up-regulated while six proteins were down-regulated when comparing MI to MII oocytes. The expression of ERp57, an endoplasmic reticulum chaperone, underwent a dramatic increase between MI and MII oocytes, and became concentrated in a dome-shaped area of the cell surface within the microvillar region. A similar profile was observed during spermatogenesis, and sperm ERp57 eventually localized to the head and flagellum surfaces, finally ending in the equatorial region of acrosome-reacted sperm. Given the localization pattern, we tested and found that a polyclonal antiserum created against recombinant rat ERp57 significantly inhibited spermatozoa from penetrating zona pellucida-free oocytes without affecting either sperm motility or the acrosome reaction. These results indicate that ERp57 expression on oocytes, and possibly sperm, plays an important physiological role during sperm-egg fusion. PMID:24415168

  4. Calcium waves occur as Drosophila oocytes activate.

    PubMed

    Kaneuchi, Taro; Sartain, Caroline V; Takeo, Satomi; Horner, Vanessa L; Buehner, Norene A; Aigaki, Toshiro; Wolfner, Mariana F

    2015-01-20

    Egg activation is the process by which a mature oocyte becomes capable of supporting embryo development. In vertebrates and echinoderms, activation is induced by fertilization. Molecules introduced into the egg by the sperm trigger progressive release of intracellular calcium stores in the oocyte. Calcium wave(s) spread through the oocyte and induce completion of meiosis, new macromolecular synthesis, and modification of the vitelline envelope to prevent polyspermy. However, arthropod eggs activate without fertilization: in the insects examined, eggs activate as they move through the female's reproductive tract. Here, we show that a calcium wave is, nevertheless, characteristic of egg activation in Drosophila. This calcium rise requires influx of calcium from the external environment and is induced as the egg is ovulated. Pressure on the oocyte (or swelling by the oocyte) can induce a calcium rise through the action of mechanosensitive ion channels. Visualization of calcium fluxes in activating eggs in oviducts shows a wave of increased calcium initiating at one or both oocyte poles and spreading across the oocyte. In vitro, waves also spread inward from oocyte pole(s). Wave propagation requires the IP3 system. Thus, although a fertilizing sperm is not necessary for egg activation in Drosophila, the characteristic of increased cytosolic calcium levels spreading through the egg is conserved. Because many downstream signaling effectors are conserved in Drosophila, this system offers the unique perspective of egg activation events due solely to maternal components. PMID:25564670

  5. Apoptosis in mammalian oocytes: a review.

    PubMed

    Tiwari, Meenakshi; Prasad, Shilpa; Tripathi, Anima; Pandey, Ashutosh N; Ali, Irfan; Singh, Arvind K; Shrivastav, Tulsidas G; Chaube, Shail K

    2015-08-01

    Apoptosis causes elimination of more than 99 % of germ cells from cohort of ovary through follicular atresia. Less than 1 % of germ cells, which are culminated in oocytes further undergo apoptosis during last phases of oogenesis and depletes ovarian reserve in most of the mammalian species including human. There are several players that induce apoptosis directly or indirectly in oocytes at various stages of meiotic cell cycle. Premature removal of encircling granulosa cells from immature oocytes, reduced levels of adenosine 3',5'-cyclic monophosphate and guanosine 3',5'-cyclic monophosphate, increased levels of calcium (Ca(2+)) and oxidants, sustained reduced level of maturation promoting factor, depletion of survival factors, nutrients and cell cycle proteins, reduced meiotic competency, increased levels of proapoptotic as well as apoptotic factors lead to oocyte apoptosis. The BH3-only proteins also act as key regulators of apoptosis in oocyte within the ovary. Both intrinsic (mitochondria-mediated) as well as extrinsic (cell surface death receptor-mediated) pathways are involved in oocyte apoptosis. BID, a BH3-only protein act as a bridge between both apoptotic pathways and its cleavage activates cell death machinery of both the pathways inside the follicular microenvironment. Oocyte apoptosis leads to the depletion of ovarian reserve that directly affects reproductive outcome of various mammals including human. In this review article, we highlight some of the important players and describe the pathways involved during oocyte apoptosis in mammals. PMID:25958165

  6. INTRAMITOCHONDRIAL YOLK-CRYSTALS OF FROG OOCYTES

    PubMed Central

    Massover, William H.

    1971-01-01

    Electron microscope examination of thin sections of bullfrog (Rana catesbeiana) ovarian oocytes has shown the presence of mitochondria containing yolk-crystal inclusions in oocytes of all sizes, from 160 to 1500 µ mean diameter. The hexagonally shaped yolk-crystals have major periodicities of 73.8 ± 10.7 A (n = 100). Several forms of modified mitochondria, observed in the smaller oocytes, may be arranged into a series of structurally intermediate forms between standard oocyte mitochondria and the typical mitochondria with yolk-crystal inclusions. The observation of such intermediate forms is consistent with proposals that the yolk-crystal inclusions arise within a limited portion of the oocyte chondriome by a complex process of mitochondrial differentiation. PMID:5102556

  7. Sirtuin Inhibition Adversely Affects Porcine Oocyte Meiosis

    PubMed Central

    Zhang, Liang; Ma, Rujun; Hu, Jin; Ding, Xiaolin; Xu, Yinxue

    2015-01-01

    Sirtuins have been implicated in diverse biological processes, including oxidative stress, energy metabolism, cell migration, and aging. Here, we employed Sirtuin inhibitors, nicotinamide (NAM) and Sirtinol, to investigate their effects on porcine oocyte maturation respectively. The rate of polar body extrusion in porcine oocytes decreased after treatment with NAM and Sirtinol, accompanied with the failure of cumulus cell expansion. We further found that NAM and Sirtinol significantly disrupted oocyte polarity, and inhibited the formation of actin cap and cortical granule-free domain (CGFD). Moreover, the abnormal spindles and misaligned chromosomes were readily detected during porcine oocyte maturation after treatment with NAM and Sirtinol. Together, these results suggest that Sirtuins are involved in cortical polarity and spindle organization in porcine oocytes. PMID:26176547

  8. Apoptosis in Batch Cultures of Chinese Hamster Ovary Cells

    E-print Network

    Sinskey, Anthony J.

    Apoptosis in Batch Cultures of Chinese Hamster Ovary Cells J. Goswami,1 A. J. Sinskey,2 H. Steller of the main problems in the culture of Chinese Hamster Ovary (CHO) cells continues to be the inability. Keywords: cell culture; Chinese Hamster Ovary; apopto- sis; caspase; bcl-2 INTRODUCTION Chinese Hamster

  9. MULTIDRUG RESISTANT TRANSPORT ACTIVITY PROTECTS OOCYTES FROM CHEMOTHERAPEUTIC AGENTS AND CHANGES DURING OOCYTE MATURATION

    PubMed Central

    Brayboy, Lynae M.; Oulhen, Nathalie; Witmyer, Jeannine; Robins, Jared; Carson, Sandra; Wessel, Gary M.

    2013-01-01

    Objective To determine the multidrug resistant (MDR) transporter activity in oocytes and their potential role in oocyte susceptibility to chemotherapy. Design Experimental laboratory study Setting University and Academic Center for reproductive medicine. Patients/Animals Women with eggs retrieved for ICSI cycles and adult female FVBN and B6C3F1 mouse strains. Intervention Inhibition of MDR activity in oocytes. Main Outcome measure(s) Efflux activity of MDRs using quantitative fluorescent dye efflux and oocyte cell death when exposed to chemotherapy. Results Oocytes effluxed fluorescent reporters and this activity was significantly reduced in the presence of the MDR inhibitor PSC 833. GV oocytes are more efficient at efflux compared to M2 oocytes. Human oocytes exposed to cyclophosphamide and PSC 833 showed cell death using two different viability assays compared to controls and those exposed to cyclophosphamide alone. Immunoblots detected MDR-1 in all oocytes with the greatest accumulation in the GV stage. Conclusions Oocytes have a vast repertoire of active MDRs. The implications of this study are that these protective mechanisms are important during oogenesis, and these activities change with maturation, increasing susceptibility to toxicants. Future directions may exploit the up regulation of these transporters during gonadotoxic therapy. PMID:23953328

  10. Diffused Intra-Oocyte Hydrogen Peroxide Activates Myeloperoxidase and Deteriorates Oocyte Quality

    PubMed Central

    Khan, Sana N.; Shaeib, Faten; Najafi, Tohid; Kavdia, Mahendra; Gonik, Bernard; Saed, Ghassan M.; Goud, Pravin T.; Abu-Soud, Husam M.

    2015-01-01

    Hydrogen peroxide (H2O2) is a relatively long-lived signaling molecule that plays an essential role in oocyte maturation, implantation, as well as early embryonic development. Exposure to relatively high levels of H2O2 functions efficiently to accelerate oocyte aging and deteriorate oocyte quality. However, little precise information exists regarding intra-oocyte H2O2 concentrations, and its diffusion to the oocyte milieu. In this work, we utilized an L-shaped amperometric integrated H2O2-selective probe to directly and quantitatively measure the real-time intra-oocyte H2O2 concentration. This investigation provides an exact measurement of H2O2 in situ by reducing the possible loss of H2O2 caused by diffusion or reactivity with other biological systems. This experiment suggests that the intra-oocyte H2O2 levels of oocytes obtained from young animals are reasonably high and remained constant during the procedure measurements. However, the intra-oocyte H2O2 concentration dropped significantly (40-50% reduction) in response to catalase pre-incubation, suggesting that the measurements are truly H2O2 based. To further confirm the extracellular diffusion of H2O2, oocytes were incubated with myeloperoxidase (MPO), and the diffused H2O2 triggered MPO chlorinating activity. Our results show that the generated hypochlorous acid (HOCl) facilitated the deterioration in oocyte quality, a process that could be prevented by pre-incubating the oocytes with melatonin, which was experimentally proven to be oxidized utilizing HPLC methods. This study is the first to demonstrate direct quantitative measurement of intracellular H2O2, and its extracellular diffusion and activation of MPO as well as its impact on oocyte quality. These results may help in designing more accurate treatment plans in assisted reproduction under inflammatory conditions. PMID:26197395

  11. Experimental sporotrichosis in Syrian hamsters.

    PubMed Central

    Charoenvit, Y; Taylor, R L

    1979-01-01

    Syrian hamsters were infected with Sporothrix schenckii by subcutaneous footpad inoculation. Two types of infection could be uniformly induced: a self-limited, lymphatic infection resembling the classical disease in humans, and a generalized nonfatal infection. An infecting dose of approximately 5,300 yeast cells produced the localized subcutaneous-lymphatic disease which was limited to a single limb. In contrast, a 1,000-fold increase in the inoculum temporarily overwhelmed the animals' defense mechanisms, producing a systemic infection involving the liver and spleen. These models were used to demonstrate the development of increased resistance to subsequent infection following either infection or active immunization with ribosomal fractions or trypsinized cell wall antigens of S. schenckii incorporated in Freund complete adjuvant. Agglutination titers were detectable in all animals that were either infected or immunized. In one group of infected animals, the titers persisted for at least 1 year after three booster doses of Formalin-killed S. schenckii. The ability to produce an infection in hamsters which closely resembles the disease seen in humans makes the animal a good model with which to study experimental sporotrichosis. PMID:422244

  12. Maturation arrest of human oocytes at germinal vesicle stage.

    PubMed

    Chen, Zhi Qin; Ming, Teng Xiao; Nielsen, Hans Ingolf

    2010-09-01

    Maturation arrest of human oocytes may occur at various stages of the cell cycle. A total failure of human oocytes to complete meiosis is rarely observed during assisted conception cycles. We describe here a case of infertile couples for whom all oocytes repeatedly failed to mature at germinal vesicle (GV) stage during in vitro fertilization/Intra cytoplasmic sperm injection (IVF/ICSI). The patient underwent controlled ovarian stimulation followed by oocyte retrieval and IVF/ICSI. The oocytes were stripped off cumulus cells prior to the ICSI procedure and their maturity status was defined. The oocyte maturation was repeatedly arrested at the GV. Oocyte maturation arrest may be the cause of infertility in this couple. The recognition of oocyte maturation arrest as a specific medical condition may contribute to the characterization of the currently known as "oocyte factor." The cellular and genetic mechanisms causing oocyte maturation arrest should be the subject for further investigation. PMID:21234179

  13. Clinical experience and applications of oocyte cryopreservation.

    PubMed

    Porcu, E; Fabbri, R; Damiano, G; Giunchi, S; Fratto, R; Ciotti, P M; Venturoli, S; Flamigni, C

    2000-11-27

    Oocyte cryopreservation is a viable solution for the ethical problems related to embryo storage, and the only available technique for preservation of fertility in women who have to undergo chemo- or radiotherapy. The main problems with oocyte cryopreservation are concerned with the survival rate and the fertilization rate. Recently the introduction of the intracytoplasmic sperm injection (ICSI) led to an increase in the fertilization rate. The success achieved with the first case treated encouraged us to set up a clinical trial on human oocyte cryopreservation. In the first stage of the study, 23 women with tubal infertility were enrolled. Superovulation was induced and 375 oocytes were retrieved; of these 338 oocytes were frozen. The survival rate was 59.5% and was independant of the duration of cryopreservation or the presence of cumulus. The normal fertilization rate was 64.4%, and only 7.5% of fertilizations were abnormal. A total of 90.8% of fertilized oocytes cleaved. A mean of 3.1+/-1.3 embryos per patient were transferred. Three pregnancies were achieved. In the second stage of our investigation, more patients were enrolled and similar results were observed. Sixteen pregnancies were achieved. A further stage of the investigation involved the fertilization of frozen oocytes with frozen sperm and even these resulted in a pregnancy. Our study demonstrated that pregnancies can also be achieved when frozen eggs are fertilized by testicular and epididymal sperm. As a consequence of the success of our investigations, a program of oocyte cryopreservation for oncological patients has been initiated in our centre. In our opinion, oocyte cryopreservation is, at present, a safe and efficient technique as documented by the birth of several healthy children. PMID:11155951

  14. LSH hamster model of syphilitic infection.

    PubMed Central

    Schell, R F; LeFrock, J L; Chan, J K; Bagasra, O

    1980-01-01

    The inbred LSH/Se LAK strain of hamster can be infected with Treponema pallidum Bosnia A, the causative agent of endemic syphilis. When infected, this strain consistently produced extensive chronic skin lesions that persisted for 6 to 9 months, even in the presence of peak antitreponemal antibody titers. The lymph nodes increased in weight and contained measurable numbers of treponemes. This infection also gave the hamster cross-immunity to T. pallidum Nichols and Treponema pertenue, the causative agents of venereal syphilis and frambesia, respectively. LSH hamsters are thus an excellent model to study the immune response mechanisms to syphilitic infection. Images Fig. 1 PMID:6995327

  15. Maternal factors required for oocyte developmental competence in mice

    PubMed Central

    Ma, Jun-Yu; Li, Mo; Luo, Yi-Bo; Song, Shuhui; Tian, Dongmei; Yang, Jin; Zhang, Bing; Hou, Yi; Schatten, Heide; Liu, Zhonghua; Sun, Qing-Yuan

    2013-01-01

    During mouse antral follicle development, the oocyte chromatin gradually transforms from a less condensed state with no Hoechst-positive rim surrounding the nucleolus (NSN) to a fully condensed chromatin state with a Hoechst-positive rim surrounding the nucleolus (SN). Compared with SN oocytes, NSN oocytes display a higher gene transcription activity and a lower rate of meiosis resumption (G2/M transition), and they are mostly arrested at the two-cell stage after in vitro fertilization. To explore the differences between NSN and SN oocytes, and the maternal factors required for oocyte developmental competence, we compared the whole-transcriptome profiles between NSN and SN oocytes. First, we found that the NSN and SN oocytes were different in their metabolic pathways. In the phosphatidylinositol signaling pathway, the SN oocytes tend to produce diacylglycerol, whereas the NSN oocytes tend to produce phosphatidylinositol (3,4,5)-trisphosphate. For energy production, the SN oocytes and NSN oocytes differed in the gluconeogenesis and in the synthesis processes. Second, we also found that the key genes associated with oocyte meiosis and/or preimplantation embryo development were differently expressed in the NSN and SN oocytes. Our results illustrate that during the NSN-SN transition, the oocytes change their metabolic activities and accumulate maternal factors for further oocyte maturation and post-fertilization embryo development. PMID:23673344

  16. Oocyte environment: follicular fluid and cumulus cells are critical for oocyte health.

    PubMed

    Dumesic, Daniel A; Meldrum, David R; Katz-Jaffe, Mandy G; Krisher, Rebecca L; Schoolcraft, William B

    2015-02-01

    Bidirectional somatic cell-oocyte signaling is essential to create a changing intrafollicular microenvironment that controls primordial follicle growth into a cohort of growing follicles, from which one antral follicle is selected to ovulate a healthy oocyte. Such intercellular communications allow the oocyte to determine its own fate by influencing the intrafollicular microenvironment, which in turn provides the necessary cellular functions for oocyte developmental competence, which is defined as the ability of the oocyte to complete meiosis and undergo fertilization, embryogenesis, and term development. These coordinated somatic cell-oocyte interactions attempt to balance cellular metabolism with energy requirements during folliculogenesis, including changing energy utilization during meiotic resumption. If these cellular mechanisms are perturbed by metabolic disease and/or maternal aging, molecular damage of the oocyte can alter macromolecules, induce mitochondrial mutations, and reduce adenosine triphosphate production, all of which can harm the oocyte. Recent technologies are now exploring transcriptional, translational, and post-translational events within the human follicle with the goal of identifying biomarkers that reliably predict oocyte quality in the clinical setting. PMID:25497448

  17. Spontaneous endomyometrial neoplasms in aging Chinese hamsters

    SciTech Connect

    Brownstein, D.G.; Brooks, A.L.

    1980-05-01

    Twenty-one endomyometrial neoplasms among 93 nulliparous noninbred Chinese hamsters were evaluated. The median survival time of the 93 females was 1040 days. The median age of hamsters with endomyometrial neoplasms was 1200 days. Neoplasms were classified as carcinomas or malignant mixed muellerian tumors of the endometrium and benign or malignant myometrial neoplasms. There were 13 endometrial adenocarcinomas. Three tumors were mixed adenosquamous carcinomas, which occurred in significantly older Chinese hamsters than did adenocarcinomas. Three malignant mixed muellerian tumors consisted of 2 carcinosarcomas and 1 mixed mesodermal tumor. The 2 myometrial neoplasms were a lelomyoma and a lelomyosarcoma. The classification and relative frequency of these neoplasms were similar to endomyometrial neoplasms of women, which makes Chinese hamsters useful subjects for studies of spontaneous endomyometrial cancers.

  18. Induction of lyme arthritis in LSH hamsters.

    PubMed Central

    Schmitz, J L; Schell, R F; Hejka, A; England, D M; Konick, L

    1988-01-01

    In studies of experimental Lyme disease, a major obstacle has been the unavailability of a suitable animal model. We found that irradiated LSH/Ss Lak hamsters developed arthritis after injection of Borrelia burgdorferi in the hind paws. When nonirradiated hamsters were injected in the hind paws with B. burgdorferi, acute transient synovitis was present. A diffuse neutrophilic infiltrate involved the synovia and periarticular structures. The inflammation was associated with edema, hyperemia, and granulation tissue. Numerous spirochetes were seen in the synovial and subsynovial tissues. The histopathologic changes were enhanced in irradiated hamsters. The onset and duration of the induced swelling were dependent on the dose of radiation and the inoculum of spirochetes. Inoculation of irradiated hamsters with Formalin-killed spirochetes or medium in which B. burgdorferi had grown for 7 days failed to induce swelling. This animal model should prove useful for studies of the immune response to B. burgdorferi and the pathogenesis of Lyme arthritis. Images PMID:3410540

  19. Assisted oocyte activation following ICSI fertilization failure.

    PubMed

    Vanden Meerschaut, Frauke; Nikiforaki, Dimitra; Heindryckx, Björn; De Sutter, Petra

    2014-05-01

    The capacity of intracytoplasmic sperm injection (ICSI) to permit almost any type of spermatozoa to fertilize oocytes has made it the most successful treatment for male factor infertility. Despite its high success rates, fertilization failure following ICSI still occurs in 1-3% of couples. Assisted oocyte activation (AOA) is being increasingly applied in human assisted reproduction to restore fertilization and pregnancy rates in couples with a history of ICSI fertilization failure. However, controversy still exists mainly because the artificial activating agents do not mimic precisely the initial physiological processes of mammalian oocyte activation, which has led to safety concerns. This review addresses the mechanism of human oocyte activation and the relatively rare phenomenon of fertilization failure after ICSI. Next, it describes the current diagnostic approaches and focuses on the application, efficiency and safety of AOA in human assisted reproduction. PMID:24656559

  20. Directed Student Inquiry: Modeling in Roborovsky Hamsters

    NSDL National Science Digital Library

    Adam Bouchard

    2007-04-01

    In this inquiry-based activity, Roborovsky hamsters are used to provide students with an opportunity to develop their skills of analysis, inquiry, and design. These hamsters are easy to maintain, yet offer students a means to use conventional techniques and those of their own design to make further observations through measuring, assessing, and data collection. Based on the premise that this is a directed rather than dictated student inquiry, the activity will vary based on discussions and recommendations suggested by each class.

  1. Djungarian Hamsters — Small Graminivores with Daily Torpor

    Microsoft Academic Search

    Thomas Ruf; Gerhard Heldmaier

    \\u000a The species of interest in this chapter, the Djungarian dwarf hamster (Phodopus sungorus), is sometimes also called the hairy-footed hamster. This name, which refers to fur covering even the soles of the feet in\\u000a this species, indicates an adaptation to extremely harsh climatic conditions in its natural habitat, the subarid steppes of\\u000a continental Asia. Among these steppes, the Djungarian (or

  2. Synaptic anomalies in fetal bovine oocytes.

    PubMed

    Koykul, W; Basrur, P K

    1994-02-01

    Chromosome pairing abnormalities in oocytes of bovine fetuses ranging in age from 81 to 130 days were studied using the surface-spread whole-mount technique. The synaptic abnormalities included partial or total asynapsis, nonhomologous pairing, and mid-pachytene degeneration with asynapsis constituting the most common category. Oocytes showing synaptic abnormalities were less frequent in younger fetuses and more abundant in fetuses older than 110 days. Histologic signs of oocyte degeneration, evident in all fetuses, were most striking in ovaries of fetuses older than 120 days. The temporal relationship of these events suggests that chromosome pairing anomalies may be associated with oocyte degeneration, although their exact role in precipitating oocyte atresia remains unclear. The presence of abnormal oocytes and follicles in the vicinity of the medullary cords seems to suggest that these germ cells may be exposed to deleterious substances from the degenerating rete cords and that the synaptic errors may be the meiotic manifestations of chromosome damages sustained by germ cells during the repeated oogonial divisions in an environment unconducive to mitosis and maturation of female germ cells. PMID:8181739

  3. The use of ejaculated boar semen after freezing in 2 or 6% glucerol for in vitro fertilization of porcine oocytes matured in vitro.

    PubMed

    Zheng, Y S; Fiser, P; Sirard, M A

    1992-12-01

    Two concentrations of glycerol in a freezing diluent were tested with respect to the in vitro fertilizing capacity of frozen-thawed boar spermatozoa which, before exposure to oocytes, were subjected to 3 methods of fractionation. These were 1) the upper fraction, 2) the swim-up and 3) percoll gradinet-centrifugation. The highest proportions of motile spermatozoa were obtained by the swim-up procedure, while acrosomal integrity was best preserved by the upper fraction procedure. Raising the glycerol concentration from 2 to 6% (v/v) during freezing decreased the proportion of spermatozoa with a normal apical ridge. Spermatozoa separated by the upper fraction method showed the greatest penetration of oocytes and produced the highest incidence of polyspermy. The glycerol level affected penetration and polyspermy only with spermatozoa separated in a percoll gradient, where the higher level of glycerol increased oocytes penetration and polyspermy. Pronuclei formation was influenced by the separation procedure and by the glycerol concentration in the freezing diluent. The results indicate that frozen boar semen can be used for in vitro fertilization more successfully than fresh semen since penetration by frozen upper fraction spermatozoa was similar to, the degree of polyspermy was lower, and the formation of two pronuclei was greater (P<0.01) than in oocytes exposed to fresh semen. PMID:16727204

  4. Artificial oocyte activation and human failed-matured oocyte vitrification followed by in vitro maturation.

    PubMed

    Liu, Y; Cao, Y X; Zhang, Z G; Xing, Q

    2013-02-01

    The investigation presented in this paper was conducted on the effect of oocytes activation on frozen-thawed human immature oocytes followed by in vitro maturation (IVM). A total of 386 failed-matured oocytes (germinal vesicle (GV) and metaphase I (MI) stages) was randomly divided into two groups: fresh group and vitrification group, GV group and MI group, respectively). The matured oocytes were subject to intracytoplasmic sperm injection (ICSI) after IVM had been carried out. The vitrification group was randomly divided into two groups: controlled and artificial oocyte activation (AOA). The injected oocytes in the controlled group were cultured in cleavage medium. The AOA group oocytes were activated by exposing them to 7% anhydrous alcohol for 6 min then cultured in cleavage medium as well. The rates of fertilization and early embryonic development were compared between the controlled and AOA groups. In MI vitrification group, the high-quality embryo formation rate and blastocyst formation rate were significantly higher in the AOA group than in the controlled group (P < 0.01). In the GV vitrification group, the high-quality embryo formation rate was significantly higher in the AOA group than in the controlled group (P < 0.05). These results indicate that AOA may be good for early embryonic development of vitrified immature human oocytes. PMID:21867595

  5. Proteomes of Animal Oocytes: What Can We Learn for Human Oocytes in the In Vitro Fertilization Programme?

    PubMed Central

    Virant-Klun, Irma; Krijgsveld, Jeroen

    2014-01-01

    Oocytes are crucial cells for mammalian reproduction, yet the molecular principles underlying oocyte development are only partially understood. Therefore, contemporary proteomic approaches have been used increasingly to provide new insights into oocyte quality and maturation in various species such as mouse, pig, and cow. Especially, animal studies have helped in elucidating the molecular status of oocytes during in vitro maturation and other procedures of assisted reproduction. The aim of this review is to summarize the literature on mammalian oocyte proteome and secretome research in the light of natural and assisted reproduction and on lessons to be learned for human oocytes, which have so far remained inaccessible for proteome analysis. PMID:24804254

  6. In vitro maturation of ovine oocytes in the absence of continuous 5% CO2 in a portable incubator

    E-print Network

    Byrd, Susan Rebekah Walker

    1995-01-01

    differentiate both biochemically and morphologically to eventually acquire meiotic competence (63). In the ovarian follicle, the oocyte is surrounded by layers of follicular cells that extend processes through the zona pellucida into the oolema...). The reaction proceeds with release of the outer acrosomal membrane and fusion of the inner acrosomal membrane to the plasma membrane of the sperm head, thus releasing acrosomal enzymes, primarily acrosin, that aid the sperm in penetrating the zona pellucida...

  7. Expression of FSH receptor in the hamster ovary during perinatal development.

    PubMed

    Chakraborty, Prabuddha; Roy, Shyamal K

    2015-01-15

    FSH plays an important role in ovarian follicular development, and it functions via the G-protein coupled FSH receptor. The objectives of the present study were to determine if full-length FSHR mRNA and corresponding protein were expressed in fetal through postnatal hamster ovaries to explain the FSH-induced primordial follicle formation, and if FSH or estrogen (E) would affect the expression. A full-length and two alternately spliced FSHR transcripts were expressed from E14 through P20. The level of the full-length FSHR mRNA increased markedly through P7 before stabilizing at a lower level with the formation and activation of primordial follicles. A predicted 87?kDa FSHR protein band was detected in fetal through P4 ovaries, but additional bands appeared as ovary developed. FSHR immunosignal was present in undifferentiated somatic cells and oocytes in early postnatal ovaries, but was granulosa cells specific after follicles formed. Both eCG and E significantly up-regulated full-length FSHR mRNA levels. Therefore, FSHR is expressed in the hamster ovary from the fetal life to account for FSH-induced primordial follicle formation and cAMP production. Further, FSH or E regulates the receptor expression. PMID:25462586

  8. Penetration of concrete targets

    SciTech Connect

    Forrestal, M.J. [Sandia National Labs., Albuquerque, NM (United States); Cargile, J.D. [Corps of Engineers, Vicksburg, MS (United States). Waterways Experiment Station; Tzou, R.D.Y. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Mechanical Engineering

    1993-08-01

    We developed penetration equations for ogive-nosed projectiles that penetrated concrete targets after normal impact. Our penetration equations predict axial force on the projectile nose, rigid-body motion, and final penetration depth. For target constitutive models, we conducted triaxial material experiments to confining pressures of 600 MPa and curve-fit these data with a linear pressure-volumetric strain relation and with a linear Mohr-Coulomb, shear strength-pressure relation. To verify our penetration equations, we conducted eleven penetration experiments with 0.90 kg, 26.9-mm-diameter, ogive-nosed projectiles into 1.37-m-diameter concrete targets with unconfined compressive strengths between 32-40 MPa. Predictions from our penetration equation are compared with final penetration depth measurements for striking velocities between 280--800 m/s.

  9. Oocyte cryopreservation for donor egg banking.

    PubMed

    Cobo, Ana; Remohí, José; Chang, Ching-Chien; Nagy, Zsolt Peter

    2011-09-01

    Oocyte donation is an efficient alternative to using own oocytes in IVF treatment for different indications. Unfortunately, 'traditional' (fresh) egg donations are challenged with inefficiency, difficulties of synchronization, very long waiting periods and lack of quarantine measures. Given the recent improvements in the efficiency of oocyte cryopreservation, it is reasonable to examine if egg donation through oocyte cryopreservation has merits. The objective of the current manuscript is to review existing literature on this topic and to report on the most recent outcomes from two established donor cryobank centres. Reports on egg donation using slow freezing are scarce and though results are encouraging, outcomes are not yet comparable to a fresh egg donation treatment. Vitrification on the other hand appears to provide high survival rates (90%) of donor oocytes and comparable fertilization, embryo development, implantation and pregnancy rates to traditional (fresh) egg donation. Besides the excellent outcomes, the ease of use for both donors and recipients, higher efficiency, lower cost and avoiding the problem of synchronization are all features associated with the benefit of a donor egg cryobank and makes it likely that this approach becomes the future standard of care. Oocyte donation is one of the last resorts in IVF treatment for couples challenged with infertility problems. However, traditional (fresh) egg donation, as it is performed today, is not very efficient, as typically all eggs from one donor are given to only one recipient, it is arduous as it requires an excellent synchronization between the donor and recipient and there are months or years of waiting time. Because of the development of an efficient oocyte cryopreservation technique, it is now possible to cryo-store donor (as well as non-donor) eggs, maintaining their viability and allowing their use whenever there is demand. Therefore, creating a donor oocyte cryobank would carry many advantages. In the present manuscript, the current experience with oocyte donation using cryopreservation technology is reviewed. The outcomes of two recently established donor egg cryobanks at Instituto Valenciano de Infertilidad in Spain and Reproductive Biology Associates in the USA (involving a large number of cases) demonstrate that egg cryo-survival is high and that fertilization, embryo development, implantation and pregnancy rates are similar to those reported after fresh egg donation. It also provides additional advantages of being more efficient, more economical, easier for both donors and recipients and potentially also safer, because eggs can now be quarantined for 6 months (or longer) to retest for infectious diseases in the donors. It is the opinion of the authors, based on several advantages associated with the use of donor egg cryobanking, that in the future there will be fewer traditional egg donations and increasingly more cryo-egg donations. PMID:21767989

  10. Maternal control of oocyte quality in cattle "a review".

    PubMed

    Moussa, M; Shu, J; Zhang, X H; Zeng, F

    2015-04-01

    The oocyte is a central regulator of multiple aspects of female fertility, including ovarian follicular development and early embryogenesis. During its prolonged diplotene arrest, the oocyte is subjected to endogenous (i.e., reactive oxygen species from metabolism) and exogenous (i.e., heat stress, malnutrition) sources of damage-inducing factors, which may lead to a progressive deterioration of oocyte quality. A deficit in oocyte competence can lead not only to a failure of fertilization but also to a lower developmental rate after fertilization. Thus, an appropriate environment for growth and maturation of the oocyte, in vivo and in vitro, is critical to ensure optimal oocyte quality. The objectives of the current review are to give an overview of some maternal key factors that influence oocyte quality in cattle and describe some of the findings to date in the hope of obtaining competent oocytes that could be used for clinical and applied purposes. PMID:25726438

  11. Penetration of concrete targets

    Microsoft Academic Search

    M. J. Forrestal; J. D. Cargile; R. D. Y. Tzou

    1993-01-01

    We developed penetration equations for ogive-nosed projectiles that penetrated concrete targets after normal impact. Our penetration equations predict axial force on the projectile nose, rigid-body motion, and final penetration depth. For target constitutive models, we conducted triaxial material experiments to confining pressures of 600 MPa and curve-fit these data with a linear pressure-volumetric strain relation and with a linear Mohr-Coulomb,

  12. Optical coherence tomography of malignancy in hamster cheek pouches

    E-print Network

    Chen, Zhongping

    Optical coherence tomography of malignancy in hamster cheek pouches Erin S. Matheny Nevine M. Hanna-time spatially resolved blood flow in mi- crovasculature. Hamster cheek pouches with induced dysplasia Golden Syrian hamsters, 0.5% 9,10-dimethyl-1,2-benzanthracene induces carcinogenesis over 10 weeks

  13. Establishment and persistence of photoperiodic memory in hamsters

    E-print Network

    Zucker, Irving

    Establishment and persistence of photoperiodic memory in hamsters Brian J. Prendergast* , Michael R reproduction in Siberian hamsters. By contrast, intermedi- ate-duration day lengths (12.5­14 h long) either of these outcomes transpires depends on an animal's photoperiodic history, suggesting that hamsters must encode

  14. Spielerisches Erlernen der Programmierung mit dem Java-Hamster-Modell

    E-print Network

    Appelrath, Hans-Jürgen

    Spielerisches Erlernen der Programmierung mit dem Java- Hamster-Modell Dietrich Boles Department Oldenburg boles@informatik.uni-oldenburg.de Abstract: Das Java-Hamster-Modell ist ein spezielles Programmierkonzepte und den Programmentwurf kennen, indem sie so genannte Hamster-Programme entwickeln, mit denen sie

  15. Meiotic Recombination in Human Oocytes Edith Y. Cheng1.

    E-print Network

    Broman, Karl W.

    Meiotic Recombination in Human Oocytes Edith Y. Cheng1. , Patricia A. Hunt2. , Theresa A. Naluai, we initiated studies of crossover-associated proteins (e.g., MLH1) in human fetal oocytes to analyze in Human Oocytes. PLoS Genet 5(9): e1000661. doi:10.1371/journal.pgen.1000661 Editor: R. Scott Hawley

  16. A new method to induce oocyte maturation in holothuroids (Echinodermata)

    Microsoft Academic Search

    ALINE LÉONET; RICHARD RASOLOFONIRINA; RUDDY WATTIEZ; MICHEL JANGOUX; IGOR EECKHAUT

    2009-01-01

    Oocyte maturation in sea cucumbers is stopped during the meiosis at prophase I. Maturation naturally concludes just before spawning leading to a mature oocyte ready to be fertilized. Although thermal shocks applied on mature individuals can induce spawning, it is currently not possible to perform reliably in vitro fertilization of sea cucumber oocytes. The present paper reports the discovery of

  17. Xenopus oocyte maturation: new lessons from a good egg

    E-print Network

    Xenopus oocyte maturation: new lessons from a good egg James E. Ferrell, Jr. Summary Fully grown oocyte maturation. Oocyte maturation is initiated by a novel plasma membrane steroid hormone receptor maturation provides an interesting example of how signaling cascades entrain the cell cycle clock

  18. Mammalian oocyte maturation C. THIBAULT D. SZLLSI, Micheline GRARD

    E-print Network

    Paris-Sud XI, Université de

    Mammalian oocyte maturation C. THIBAULT D. SZÖLLÖSI, Micheline GÉRARD Université de Paris Vl et 1's experiments, as early as 1955, a final cytoplasmic maturation must run parallel to the nuclear maturation. We-culture of granulosa and cumulus-oocyte complexes during in vitro oocyte maturation. I. - Nuclear maturation A. &horbar

  19. The Mechanism of Cytoplasmic Streaming in Drosophila Melanogaster Oocytes

    E-print Network

    Monteith, Corey

    2015-01-01

    can be seen as early as stage 4 (Emmons, Phan et al. 1995),stage, the oocyte is entirely surrounded by vitelline membrane, aside from the 4stage 10b oocyte. On the left is a micrograph of an oocyte approximately 4

  20. Ammonium sulfate induced nuclear changes in the oocyte of the fish, Channa punctatus (Bl. )

    SciTech Connect

    Ram, R.N.; Sathyanesan, A.G.

    1986-06-01

    One among the common pollutants present in our riverine and lacustrine system is the commonly used fertilizer ammonium sulfate ((NH/sub 4/)/sub 2/SO/sub 4/). The unionized ammonia (UIA) base in the water is responsible for the toxicity due to its distinctive penetrative properties. Prolonged exposure of the fish Clarias batrachus to (NH/sub 4/)/sub 2/SO/sub 4/ causes endocrine changes. However, the deleterious effect of this fertilizer on the reproduction of fishes is not well recorded. In this study, (NH/sub 4/)/sub 2/SO/sub 4/-induced degenerative changes in the nucleus of early vitellogenic oocytes of C. punctatus are described.

  1. Evaluation of oocyte competency in bovine and canine species via non-invasive assessment of oocyte quality

    E-print Network

    Willingham-Rocky, Lauri A.

    2009-05-15

    ), zona pellucida integrity, cumulus cell layers, and follicle size (Leibfried and First, 1979). While these characteristics have been a useful guideline for numerous in vitro experiments, many oocytes that appear healthy and normal are incapable... pellucida) in sexually mature bitches (Farstad, 2000). A relationship between canine oocyte size and meiotic competency suggests that oocytes >110 ?m are competent to resume meiosis, but that oocytes >120 ?m are the most competent and have significantly...

  2. AUTOMATED PENETRATION A Research Project

    E-print Network

    Stamp, Mark

    i AUTOMATED PENETRATION TESTING A Research Project Presented to The Faculty of the Department UNIVERSITY The Undersigned Project Committee Approves the Project Titled AUTOMATED PENETRATION TESTING Date: #12;iv ABSTRACT AUTOMATED PENETRATION TESTING Penetration testing is used to search

  3. Fbos, a novel oocyte-specific protein, interacts with proteins important for oocyte development in rainbow trout (Oncorhynchus mykiss)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oogenesis is characterized by a series of developmentally regulated events, which result in the matured oocyte that can give rise to a new organism after fertilization. Oocyte-specific genes play critical roles in oogenesis; however, the molecular details of oocyte-specific genes are poorly defined....

  4. Hamster refractoriness: the role of insensitivity of pineal target tissues.

    PubMed

    Bittman, E L

    1978-11-10

    Hamsters exposed to short days undergo gonadal collapse followed by recrudescence and insensitivity to the regressive effects of such photoperiods. This refractoriness may be due to exhaustion of the pineal gland or desensitization of its target. Hamsters whose gonads had spontaneously recrudesced were injected with melatonin (25 micrograms per injection) once daily (known to induce regression in intact hamsters) or twice daily (reported to arrest reproduction in pinealectomized hamsters) for 7 weeks. In neither case did refractory hamsters respond to melatonin treatment. The gonads of intact hamsters treated with melatonin for 21 weeks regressed and spontaneously recrudesced along a normal time course. These results indicate that gonadal refractoriness is due to insensitivity of the target tissues of the pineal gland and imply that melantonin participates in photoperiodic regulation of reproduction in the golden hamster. PMID:568311

  5. Expression of CD44 in sheep oocytes and preimplantation embryos.

    PubMed

    Luz, J V; Alcântara-Neto, A S; Batista, R I T P; Souza, J M G; Teixeira, D I A; Melo, L M; Freitas, V J F

    2012-01-01

    The CD44 family belongs to a larger group of hyaluronic acid-binding proteins and plays important roles in oocyte maturation, fertilization and preimplantational embryo development. We analyzed the CD44 receptor in sheep oocytes and embryos. Immature oocytes (N = 66) were obtained from a local abattoir; mature oocytes (N = 35) and embryos (N = 41) were obtained by laparotomy from adult hair ewes submitted to ovarian stimulation treatment. The CD44 mRNA was detected by hemi-nested PCR, after reverse transcription, while proteins were located by indirect immunofluorescence, using anti-human CD44 monoclonal antibody. Human lymphocytes and immature bovine oocytes were used as positive and negative controls, respectively. Assessment of the oocyte nuclear stages as well as classification of the embryonic development stage were made with Hoechst 33342 staining. Indirect immunofluorescence detected CD44 expression on the surface of mature oocytes and embryos; immature oocytes did not take up the stain. These findings were supported by the RT-PCR data, which showed no mRNA templates for CD44, even after two consecutive amplifications, in material from immature oocytes and cumulus cells. The CD44 amplicons were detected after a second hemi-nested PCR in mature oocytes and embryos. The finding of CD44 in mature oocytes and preimplantational embryos could reflect the expression profile of hyaluronic acid during terminal folliculogenesis and preimplantational embryo development in sheep. PMID:22576908

  6. Temporal effects of exogenous oocyte-secreted factors on bovine oocyte developmental competence during IVM.

    PubMed

    Hussein, Tamer S; Sutton-McDowall, Melanie L; Gilchrist, Robert B; Thompson, Jeremy G

    2011-01-01

    We investigated whether paracrine signalling between the bovine oocyte and cumulus cells is altered during the course of in vitro maturation (IVM). Bovine COCs were cocultured with denuded oocytes or treated with specific oocyte-secreted factors, namely recombinant bone morphogenetic protein (BMP)-15 or growth differentiation factor (GDF)-9, beginning from 0 or 9h IVM. To generate a 9-h denuded oocyte (DO) group, COCs were cultured intact for the first 9h of IVM and then denuded. Coculturing intact COCs with DOs denuded immediately after collection or following 9h of maturation did not affect cleavage rate, but improved blastocyst yield (P<0.05) on Day 8 (51 and 61%, respectively; P<0.05) and cell number compared with COCs cultured alone (41%). Significantly, we observed higher levels of endogenous GDF-9 and BMP-15 protein in oocytes of COCs matured for 9h compared with no incubation. The addition of 175 ng mL(-1) GDF-9 or 10%v/v BMP-15 from partially purified transfected 293H cell supernatant for 24h IVM significantly enhanced development to the blastocyst stage from 40% (control) to 51 and 47%, respectively (P<0.05). However, treatment of COCs with GDF-9 or BMP-15 between 9 and 24h of IVM did not increase blastocyst yield. These results provide evidence of quantitative and possibly qualitative temporal changes in oocyte paracrine factor production during IVM. PMID:21557924

  7. IN VITRO CULTURE OF POSTIMPLANTATION HAMSTER EMBRYOS

    EPA Science Inventory

    In vitro culture of intact rat and mouse embryos has been described extensively, but information on the culture of other species is sparse. The present study examined some culture requirements of early somite stage hamster embryos and assessed the embryotoxic effects of sodium sa...

  8. Age-associated telomere shortening in mouse oocytes

    PubMed Central

    2013-01-01

    Background Oocytes may undergo two types of aging. The first is induced by exposure to an aged ovarian microenvironment before being ovulated, known as ‘reproductive or maternal aging’, and the second by either a prolonged stay in the oviduct before fertilization or in vitro aging prior to insemination, known as ‘postovulatory aging’. However, the molecular mechanisms underlying these aging processes remain to be elucidated. As telomere shortening in cultured somatic cells triggers replicative senescence, telomere shortening in oocytes during reproductive and postovulatory aging may predict developmental competence. This study aimed to ascertain the mechanisms underlying altered telomere biology in mouse oocytes during reproductive and postovulatory aging. Methods We studied Tert expression patterns, telomerase activity, cytosolic reactive oxygen species (ROS) production, and telomere length in fresh oocytes from young versus reproductively-aged female mice retrieved from oviducts at 14 h post-human chorionic gonadotropin (hCG), in vivo or in vitro postovulatory-aged mouse oocytes at 23 h post-hCG. Oocytes were collected from super-ovulated C57BL/6 J mice of 6–8 weeks or 42–48 weeks of age. mRNA and protein expressions of the Tert gene were quantified using real-time quantitative reverse transcriptase polymerase chain reaction (Q-PCR) and immunochemistry. Telomerase activity was measured by a telomeric repeat amplification protocol assay, while telomere length was measured by Q-PCR and quantitative fluorescence in situ hybridization analyses. Results The abundance of Tert expression in oocytes significantly decreased during reproductive and postovulatory aging. Immunofluorescent staining clearly demonstrated an altered pattern and intensity of TERT protein expression in oocytes during reproductive aging. Furthermore, relative telomerase activity (RTA) in oocytes from reproductively-aged females was significantly lower than that in oocytes from young females. In contrast, RTA in postovulatory-aged oocytes was similar to that in fresh oocytes. Oocytes from reproductively-aged females and postovulatory-aged oocytes showed higher ROS levels than oocytes from young females. Relative telomere length (RTL) was remarkably shorter in oocytes from reproductively-aged females compared to oocytes from young females. However, postovulatory aging had no significant effect on RTL of oocytes. Conclusions Long-term adverse effects of low telomerase activity and increased ROS exposure are likely associated with telomere shortening in oocytes from reproductively-aged female mice. PMID:24261933

  9. Serum human chorionic gonadotropin levels on the day before oocyte retrieval do not correlate with oocyte maturity

    PubMed Central

    Levy, Gary; Hill, Micah J.; Ramirez, Christina; Plowden, Torrie; Pilgrim, Justin; Howard, Robin S.; Segars, James H.; Csokmay, John

    2014-01-01

    Objective To evaluate the correlation of preretrieval quantitative serum hCG level with oocyte maturity. Design Retrospective cohort study. Setting Military assisted reproductive technology (ART) program. Patient(s) Fresh autologous ART cycles. Intervention(s) Serum hCG level the day before oocyte retrieval. Main Outcome Measure(s) Linear regression was used to correlate serum hCG levels and oocyte maturity rates. Normal oocyte maturity was defined as ? 75% and the Wilcoxon rank sum test was used to compare serum hCG levels in patients with normal and low oocyte maturity. Threshold analysis was performed to determine hCG levels that could predict oocyte maturity. Result(s) A total of 468 ART cycles were analyzed. Serum hCG level was not correlated with hCG dose; however, it was negatively correlated with body mass index (BMI). Serum hCG levels did not differ between patients with oocyte maturity of <75% and ? 75%. Serum hCG levels did not correlate with oocyte maturity rates. Receiver operator characteristic and less than efficiency curves failed to demonstrate thresholds at which hCG could predict oocyte maturity. Conclusion(s) Serum hCG levels were not correlated with oocyte maturity. Although a positive hCG was reassuring that mature oocytes would be retrieved for most patients, the specific value was not helpful. PMID:23375205

  10. Cannabinoids and hamster circadian activity rhythms.

    PubMed

    Sanford, Anna E; Castillo, Elizabeth; Gannon, Robert L

    2008-07-30

    Circadian activity rhythms in hamsters are entrained to the daily light:dark cycle by photic information arriving from the retina to the suprachiasmatic nucleus, the site of the master circadian pacemaker in mammals. The effects of light on adjusting the timing of the circadian pacemaker is modified, both positively and negatively, by a variety of transmitter systems, but the effects of endocannabinoids have not been reported. Therefore, in this study we evaluated cannabinoids specific for the cannabinoid type 1 receptor (CB(1)) for their ability to modulate light-induced phase advances in hamster circadian activity rhythms. All compounds were administered intraperitoneally. The CB(1) agonist CP55940 potently inhibited light-induced phase shifts with near 90% inhibition achieved with a dose of 0.125 mg/kg. The inhibitory effect of CP55940 was partially reversed by the CB(1) antagonist LY320135 and completely reversed with 1 mg/kg of the CB(1) antagonist AM 251. Neither LY320135 nor AM 251 had any effect on light-induced phase shifts when administered alone. Further evidence for CB(1) involvement in hamster circadian rhythms was provided by immunohistochemical detection of CB(1) receptors in four separate nuclei comprising the principal components of the hamster circadian system: the suprachiasmatic nucleus, intergeniculate leaflet of the thalamus, and dorsal and median raphe nuclei. Altogether these data indicate that the endocannabinoid system has the capability to modulate circadian rhythms in the hamster and cannabis use should be evaluated for adverse effects on circadian rhythms in humans. PMID:18582849

  11. Coculturing cumulus oocyte complexes with denuded oocytes alters zona pellucida ultrastructure in in vitro matured bovine oocytes.

    PubMed

    Choi, Byung-Hyun; Bang, Jae-Il; Jin, Jong-In; Kim, Seong-Su; Jo, Hyun-Tae; Deb, Gautam Kumar; Ghanem, Nasser; Cho, Kyu-Woan; Kong, Il-Keun

    2013-12-01

    Oocyte quality is a key factor affecting success of in vitro embryo production in cattle. Improving the microenvironment of oocytes during in vitro maturation (IVM) can increase developmental rate and embryo quality. Therefore, the objective was to determine whether denuded oocytes (DO) affect embryo development and ultrastructure of the zona pellucida (ZP) in in vitro matured bovine oocytes. Intact immature cumulus-oocytes complexes (COC) obtained from a local abattoir or by ovum pick-up (OPU) were cocultured with and without abattoir-obtained DO at a COC:DO ratio of 1:5. After IVM, DO were removed and intact DO were either fertilized or observed by scanning electron microscopy. Blastocyst quality was evaluated using a TUNEL assay. The ZP pore size decreased after IVM in COC + DO coculture, regardless of their origin (OPU, 310.5 ± 92.5 vs. 428.9 ± 148.5 nm; abattoir, 317.5 ± 68.5 vs. 358.9 ± 128.5 nm; P < 0.05; mean values ± standard deviation). Moreover, the number of ZP pores in OPU COC + DO and COC + DO was greater than those in OPU COC and COC (control) groups (56 ± 4 and 55 ± 7 vs. 50 ± 6 and 42 ± 4; P < 0.05). The rate of blastocyst development in COC + DO and OPU COC + DO groups was greater those in control and OPU COC groups (36.6% and 55.5% vs. 28.1% and 40.0%; P < 0.05). Moreover, the total cell numbers of blastocysts in COC + DO group exceeded that of control (132.91 ± 30.90 vs. 115.44 ± 24.95; P < 0.05), with no significant between OPU COC + DO and OPU COC groups (139.31 ± 42.51 vs. 137.00 ± 61.34). In conclusion, in vitro embryo development competence and quality improved when oocytes were cocultured with DO. Furthermore, there more, but smaller, ZP pores. PMID:24084231

  12. Selection of developmentally competent buffalo oocytes by brilliant cresyl blue staining before IVM

    Microsoft Academic Search

    B. M. Manjunatha; P. S. P. Gupta; M. Devaraj; J. P. Ravindra; S. Nandi

    2007-01-01

    The brilliant cresyl blue (BCB) test determines the activity of glucose-6-phosphate dehydrogenase (G6PDH); the activity of this enzyme is greatest in growing oocytes, but it declines as oocytes mature. The objective was to develop and evaluate this test for assessing development of buffalo oocytes (to select developmentally competent oocytes for increased in vitro embryo production). Oocytes were exposed to BCB

  13. The Regulation of Oocyte Maturation Ekaterina Voronina and Gary M. Wessel*

    E-print Network

    Wessel, Gary M.

    . Concept of Oocyte Maturation II. Life and Death of an Oocyte A. Oocyte Origins B. Oocyte Development C germinal vesicle (nucleus of the oocyte) GVBD germinal vesicle breakdown hCG human chorionic gonadotropin/progestin receptor MSP major sperm protein of C. elegans nAR nuclear androgen receptor nPR nuclear progesterone

  14. Developmental potential of in vitro or in vivo matured oocytes.

    PubMed

    Alcoba, Diego D; Pimentel, Anita M; Brum, Ilma S; Corleta, Helena E

    2015-02-01

    This study compared the embryological features of mature and immature oocytes (different stages) collected from stimulated cycles of in vitro fertilization (IVF). Immature oocytes were identified, classified as PI (prophase I - germinal vesicle, GV) or MI (metaphase I), were matured in vitro and fertilized using the intra-cytoplasmic sperm injection (ICSI) technique. Fertilization potential, cleavage, and subsequent transfer/cryopreservation of the embryos derived from these in vitro matured oocytes were compared with those of in vivo matured oocytes (collected at the MII stage). The characteristics of embryos derived from gametes recovered in the MI and MII stages were similar. The fertilization rate of immature oocytes recovered in PI was significantly lower than that of MII oocytes (P = 0.031), and the cleavage rate of the PI group was also lower than that of the MI (P = 0.004) and MII (P < 0.001) groups. In vitro maturation of MI oocytes is a suitable alternative when immature oocytes are recovered, as their characteristics and development are similar to those of in vivo matured oocytes. Optimization of outcomes for PI oocytes will require development of techniques that can distinguish which of these gametes will mature and fertilize. PMID:23735140

  15. Role of arachidonic acid cascade in Rhinella arenarum oocyte maturation.

    PubMed

    Ortiz, Maria Eugenia; Arias-Torres, Ana Josefina; Zelarayán, Liliana Isabel

    2015-08-01

    There are no studies that document the production of prostaglandins (PGs) or their role in Rhinella arenarum oocyte maturation. In this study, we analysed the effect of arachidonic acid (AA) and prostaglandins (PGs) on maturation, activation and pronuclear formation in R. arenarum oocytes. Our results demonstrated that AA was capable of inducing maturation in time-dependent and dose-dependent manner. Arachidonic acid-induced maturation was inhibited by indomethacin. PGs from AA hydrolysis, such as prostaglandin F2? (PGF2?) and, to a lesser extent, PGE2, induced meiosis resumption. Oocyte maturation in response to PGF2? was similar to that produced by progesterone (P4). Oocyte response to PGE1 was scarce. Rhinella arenarum oocyte PGF2?-induced maturation showed seasonal variation. From February to June, oocytes presented low sensitivity to PGF2?. In following periods, this response increased until a maximum was reached during October to January, a close temporal correlation with oocyte response to P4 being observed. The effect of PGF2? on maturation was verified by analysing the capacity of oocytes to activate and form pronuclei after being injected with homologous sperm. The cytological analysis of activated oocytes demonstrated the absence of cortical granules in oocytes, suggesting that PGF2? induces germinal vesicle breakdown (GVBD) and meiosis resumption up to metaphase II. In turn, oocytes matured by the action of PGF2? were able to form pronuclei after fertilization in a similar way to oocyte maturated by P4. In microinjection of mature cytoplasm experiments, the transformation of pre-maturation promoting factor (pre-MPF) to MPF was observed when oocytes were treated with PGF2?. In summary, our results illustrated the participation of the AA cascade and its metabolites in maturation, activation and pronuclei formation in R. arenarum. PMID:24964276

  16. General Manual Cell Penetration

    E-print Network

    Lebendiker, Mario

    lines including HeLa, Swiss 3T3, NIH 3T3, COS-7, Jurkat and NB-4 with peptides, proteins and nucleicGeneral Manual Cell Penetration Supporting material for product series CPP-C, CPP-P, CPP-A, CPP-3641-6285 100 http://www.jenabioscience.com Last update: Jun 02, 2008 1 Introduction to Cell Penetration [1

  17. Session: Hard Rock Penetration

    SciTech Connect

    Tennyson, George P. Jr.; Dunn, James C.; Drumheller, Douglas S.; Glowka, David A.; Lysne, Peter

    1992-01-01

    This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five presentations: ''Hard Rock Penetration - Summary'' by George P. Tennyson, Jr.; ''Overview - Hard Rock Penetration'' by James C. Dunn; ''An Overview of Acoustic Telemetry'' by Douglas S. Drumheller; ''Lost Circulation Technology Development Status'' by David A. Glowka; ''Downhole Memory-Logging Tools'' by Peter Lysne.

  18. Follicular penetration and targeting.

    PubMed

    Lademann, Jürgen; Otberg, Nina; Jacobi, Ute; Hoffman, Robert M; Blume-Peytavi, Ulrike

    2005-12-01

    In the past, intercellular penetration was assumed to be the most important penetration pathway of topically applied substances. First hints that follicular penetration needs to be taken into consideration were confirmed by recent investigations, presented during the workshop "Follicular Penetration and Targeting" at the 4th Intercontinental Meeting of Hair Research Societies", in Berlin 2004. Hair follicles represent an efficient reservoir for the penetration of topically applied substances with subsequent targeting of distinct cell populations, e.g., nestin-expressing follicular bulge cells. The volume of this reservoir can be determined by differential stripping technology. The follicular penetration processes are significantly influenced by the state of the follicular infundibulum; recent experimental investigations could demonstrate that it is essential to distinguish between open and closed hair follicles. Topically applied substances can only penetrate into open hair follicle. Knowledge of follicular penetration is of high clinical relevance for functional targeting of distinct follicular regions. Human hair follicles show a hair-cycle-dependent variation of the dense neuronal and vascular network. Moreover, during hair follicle cycling with initiation of anagen, newly formed vessels occur. Thus, the potential of nestin-expressing hair follicle stem cells to form neurons and blood vessels was investigated. PMID:16382687

  19. Portable seabed penetration system

    SciTech Connect

    Mahar, L.J.; Douglas, B.J.

    1986-02-25

    This patent describes a seabed penetration system which consists of: a support disposed over the portion of the seabed to be penetrated; a casing string depending from the support; a suction anchor secured to the lower end of the casing string; a push rod string slideably extending from the support through the casing string to the seabed; a seabed penetration member on the lower end of the push rod string; pump means in communication with the interior of the suction anchor to evacuate the latter and thereby temporarily anchor the casing string to the seabed; and means on the support connected to the upper ends of the casing string and the push rod string to concurrently tension the casing string and urge the push rod string downwardly to thereby effect penetration of the seabed by the seabed penetrating member, with the push rod string being restrained against buckling by the casing string. A method is described of penetrating the seabed below a body of water with a seabed penetrating member, the method including the steps of: lowering a suction anchor through the water to the upper surface of the seabed on a casing; inserting a push rod string that carries the seabed penetrating member downwardly through the casing until the penetrating member is adjacent the seabed; evacuating the suction anchor to temporarily secure the lower end of the casing string to the seabed; and tensioning the casing string while forcing the push rod string downwardly to embed the penetrating member in the seabed to thereby prevent buckling of the push rod string.

  20. Motility induction in hamster spermatozoa from caput epididymidis : effects of forward motility protein

    E-print Network

    Paris-Sud XI, Université de

    Motility induction in hamster spermatozoa from caput epididymidis : effects of forward motility observed is very often anarchic. In the hamster, we have previously provided evidence that forward motility characteristics and behaviour of hamster caput spermatozoa were investigated. Spermatozoa were diluted

  1. Follicular steroid hormones as markers of oocyte quality and oocyte development potential

    PubMed Central

    Carpintero, Nayara López; Suárez, Onica Armijo; Mangas, Carmen Cuadrado; Varea, Carolina González; Rioja, Rubén Gómez

    2014-01-01

    CONTEXT: Various components of follicular fluid are suggested as biochemical predictors of oocyte quality. Previous studies of follicular steroid hormone levels have shown disparate results when related with fertilization outcomes. AIM: The objective of the study was to relate the levels of steroid hormones of each individual follicle with oocyte maturation, fertilization results, embryo quality, and pregnancy rates. SETTINGS AND DESIGN: Prospective cohort study in a university hospital. METHODS: In 31 patients, who underwent intracytoplasmic sperm injection, it was performed an ultrasound guided aspiration of follicular fluid of the first two mature follicles from each ovary. Follicular levels of estradiol, progesterone, testosterone, and dehydroepiandrosterone sulfate were measured by chemiluminescent immunoassay. STATISTICAL ANALYSIS: Generalized estimating equation model. RESULTS: In follicular fluids with mature oocyte presence, in normal as well as in failed fertilization, there was a positive correlation between follicular testosterone and progesterone (r = 0.794, P = 0.0001 and r = 0.829, P = 0.0001). Progesterone levels were higher in cases of normal fertilization compared to failed fertilization (P = 0.003). B quality embryos came from oocytes immersed in follicular fluids with higher estradiol values and higher estradiol/progesterone and estradiol/testosterone ratios than those of C quality (P = 0.01; P = 0.0009; P = 0.001). Estradiol levels were higher in patients who achieved pregnancy (P = 0.02). CONCLUSION: The analysis of follicular hormone composition could be considered as an additional tool in oocyte selection. PMID:25395744

  2. Viruslike particles in hamster embryos, fetuses, and tumors.

    PubMed

    Sobis, H; Vandeputte, M

    1978-09-01

    Intracisternal viruslike particles were present in outbred Syrian golden and inbred ALB/Mey Pfd hamster blastocysts, embryos, and fetuses. Their morphology was identical to that of the "spoked" viruslike particles found in hamster tumors. They were released in great numbers in the embryonal tissues until day 9 of pregnancy and were found until day 13 in the fetal tissues. Thereafter, these viruslike particles were no longer observed in the fetus. They were never recorded in normal adult hamster tissues. PMID:278866

  3. Oocyte donation for stem cell research.

    PubMed

    Mertes, H; Pennings, G

    2007-03-01

    The future success of stem cell research by means of somatic cell nuclear transfer (SCNT) depends on a sufficient supply of human oocytes. However, oocyte donation presents certain risks for the donor, and concerns for women's welfare are rightly vocalized. At the same time, these risks are comparable with the risks faced by other healthy research subjects. Thus, research donation can withstand ethical scrutiny if it fulfils the same conditions as other research involving healthy human subjects. Specifically, this means that the benefits of the research project need to outweigh the harms, that risks must be minimized, that informed consent has to be guaranteed by averting undue inducement and the recruitment of vulnerable women and that donors can and should be reimbursed for their research participation. PMID:17079245

  4. Cryopreservation of Human Oocytes and Embryos

    Microsoft Academic Search

    Barry Behr; Yimin Shu

    \\u000a With the advent of assisted reproductive technology, controled ovarian hyperstimulation (COH) is usually carried out to stimulate\\u000a the growth of multiple follicles and produce multiple oocytes. Accordingly, multiple embryos are transferred to the uterus\\u000a to increase the chances of success. However, multiple embryos can also increase the likelihood of multiple pregnancies, which\\u000a are accompanied by a whole series of complications

  5. The radiosensitivity of the human oocyte

    Microsoft Academic Search

    W. H. B. Wallace; A. B. Thomson; T. W. Kelsey

    2003-01-01

    BACKGROUND: We determined the best model available for natural follicle decline in healthy women and used this to calculate the radiosensitivity of the human oocyte. METHODS: Ovarian failure was diagnosed in six patients with a median age of 13.2 years (range 12.5-16.0) who were treated with total body irradiation (14.4 Gy) at 11.5 years of age (4.9-15.1). We previously estimated

  6. Meiotic and developmental competence of prepubertal and adult swine oocytes

    Microsoft Academic Search

    R. Marchal; J. M. Feugang; C. Perreau; E. Venturi; M. Terqui; P. Mermillod

    2001-01-01

    The present study was conducted to compare meiotic and cytoplasmic competence of prepubertal and adult porcine oocytes, and the effects of EGF (0 to 100 ng\\/mL), FSH (0 to 400 ng\\/mL) and prepubertal pFF (0 to 10%) on nuclear maturation. Prepubertal oocytes were less responsive to FSH and pFF than were adult oocytes in terms of stimulation of nuclear maturation.

  7. Ultrasonic backscatter coefficient quantitative estimates from Chinese hamster ovary cell pellet biophantoms

    E-print Network

    Illinois at Urbana-Champaign, University of

    Ultrasonic backscatter coefficient quantitative estimates from Chinese hamster ovary cell pellet to the ultrasonic backscatter coefficient BSC estimate using Chinese hamster ovary CHO cells. Also introduced

  8. Social defeat differentially affects immune responses in Siberian hamsters (Phodopus sungorus)

    E-print Network

    Demas, Greg

    Social defeat differentially affects immune responses in Siberian hamsters (Phodopus sungorus concentration as well as innate and acquired immune responses in adult male Siberian hamsters (Phodopus sungorus

  9. Oogenesis of microlecithal oocytes in the viviparous teleost Heterandria formosa.

    PubMed

    Uribe, Mari Carmen; Grier, Harry J

    2011-02-01

    Viviparous teleosts exhibit two patterns of embryonic nutrition: lecithotrophy (when nutrients are derived from yolk that is deposited in the oocyte during oogenesis) and matrotrophy (when nutrients are derived from the maternal blood stream during gestation). Nutrients contained in oocytes of matrotrophic species are not sufficient to support embryonic development until term. The smallest oocytes formed among the viviparous poeciliid fish occur in the least killifish, Heterandria formosa, these having diameters of only 400 ?m. Accordingly, H. formosa presents the highest level of matrotrophy among poeciliids. This study provides histological details occurring during development of its microlecithal oocytes. Five stages occur during oogenesis: oogonial proliferation, chromatin nucleolus, primary growth (previtellogenesis), secondary growth (vitellogenesis), and oocyte maturation. H. formosa, as in all viviparous poeciliids, has intrafollicular fertilization and gestation. Therefore, there is no ovulation stage. The full-grown oocyte of H. formosa contains a large oil globule, which occupies most of the cell volume. The oocyte periphery contains the germinal vesicle, and ooplasm that includes cortical alveoli, small oil droplets and only a few yolk globules. The follicular cell layer is initially composed of a single layer of squamous cells during early previtellogenesis, but these become columnar during early vitellogenesis. They are pseudostratified during late vitellogenesis and reduce their height becoming almost squamous in full-grown oocytes. The microlecithal oocytes of H. formosa represent an extreme in fish oogenesis typified by scarce yolk deposition, a characteristic directly related to matrotrophy. PMID:21210493

  10. Oocyte-like cells induced from mouse spermatogonial stem cells

    PubMed Central

    2012-01-01

    Background During normal development primordial germ cells (PGCs) derived from the epiblast are the precursors of spermatogonia and oogonia. In culture, PGCs can be induced to dedifferentiate to pluripotent embryonic germ (EG) cells in the presence of various growth factors. Several recent studies have now demonstrated that spermatogonial stem cells (SSCs) can also revert back to pluripotency as embryonic stem (ES)-like cells under certain culture conditions. However, the potential dedifferentiation of SSCs into PGCs or the potential generation of oocytes from SSCs has not been demonstrated before. Results We report that mouse male SSCs can be converted into oocyte-like cells in culture. These SSCs-derived oocytes (SSC-Oocs) were similar in size to normal mouse mature oocytes. They expressed oocyte-specific markers and gave rise to embryos through parthenogenesis. Interestingly, the Y- and X-linked testis-specific genes in these SSC-Oocs were significantly down-regulated or turned off, while oocyte-specific X-linked genes were activated. The gene expression profile appeared to switch to that of the oocyte across the X chromosome. Furthermore, these oocyte-like cells lost paternal imprinting but acquired maternal imprinting. Conclusions Our data demonstrate that SSCs might maintain the potential to be reprogrammed into oocytes with corresponding epigenetic reversals. This study provides not only further evidence for the remarkable plasticity of SSCs but also a potential system for dissecting molecular and epigenetic regulations in germ cell fate determination and imprinting establishment during gametogenesis. PMID:22863141

  11. Characterization of urea transport in Bufo arenarum oocytes.

    PubMed

    Silberstein, Claudia; Zotta, Elsa; Ripoche, Pierre; Ibarra, Cristina

    2003-07-01

    Xenopus laevis oocytes have been extensively used for expression cloning, structure/function relationships, and regulation analysis of transporter proteins. Urea transporters have been expressed in Xenopus oocytes and their properties have been described. In order to establish an alternative system in which urea transporters could be efficiently expressed and studied, we determined the urea transport properties of ovarian oocytes from Bufo arenarum, a toad species common in Argentina. Bufo oocytes presented a high urea permeability of 22.3 x 10(-6) cm/s, which was significantly inhibited by the incubation with phloretin. The urea uptake in these oocytes was also inhibited by mercurial reagents, and high-affinity urea analogues. The urea uptake was not sodium dependent. The activation energy was 3.2 Kcal/mol, suggesting that urea movement across membrane oocytes may be through a facilitated urea transporter. In contrast, Bufo oocytes showed a low permeability for mannitol and glycerol. From these results, we propose that one or several specific urea transporters are present in ovarian oocytes from Bufo arenarum. Therefore, these oocytes cannot be used in expression studies of foreign urea transporters. The importance of Bufo urea transporter is not known but could be implicated in osmotic regulation during the laying of eggs in water. PMID:12840834

  12. Bisphenol-A and human oocyte maturation in vitro

    PubMed Central

    Machtinger, Ronit; Combelles, Catherine M.H.; Missmer, Stacey A.; Correia, Katharine F.; Williams, Paige; Hauser, Russ; Racowsky, Catherine

    2013-01-01

    STUDY QUESTION Does exposure to bisphenol-A (BPA) affect the maturation of human oocytes in vitro? SUMMARY ANSWER There was a dose–response association of BPA exposure with altered human oocyte maturation in vitro. WHAT IS KNOWN ALREADY There is widespread exposure of the general population to BPA. BPA has been detected in the human follicular fluid. Animal studies have shown that BPA exposure is associated with maturation arrest and spindle abnormalities in maturing oocytes. STUDY DESIGN, SIZE, DURATION A randomized trial, using 352 clinically discarded oocytes from 121 patients. PARTICIPANTS/MATERIALS, SETTING, METHODS The study population was drawn from patients undergoing IVF/ICSI cycles in our program at Brigham and Women's Hospital from March 2011 to April 2012. Oocytes from only one cycle for each patient were included in the study. Cycles with at least two germinal vesicle stage oocytes were included with random allocation of one oocyte to culture for 30 h without BPA and remaining sibling oocytes to medium-containing BPA (20, 200 ng/ml or 20 µg/ml). Oocytes were fixed and labeled for tubulin, actin and chromatin and examined with immunofluorescence and confocal microscopy. Oocytes were assessed for meiotic stage (n = 292), and those at metaphase II (MII, n = 175) were further classified according to their spindle configurations and patterns of chromosome alignment. McNemar's test was used to compare dichotomized maturation status. Generalized estimating equations were used to account for the correlation between oocytes from the same woman and for the spindle analysis. MAIN RESULTS AND THE ROLE OF CHANCE As the BPA dose increased, there was a decrease in the percentage of oocytes that progressed to MII (P = 0.002) and increases in the percentage of oocytes that were degenerated (P = 0.01) or that had undergone spontaneous activation (P = 0.007). Among MII oocytes, as the BPA dose increased, there was a significant trend (by test for trend) for a decreased incidence of bipolar spindles (P < 0.0001) and aligned chromosomes (P = 0.02). LIMITATIONS, REASONS FOR CAUTION Although we used sibling oocytes to overcome potential confounders, such as infertility diagnosis and maternal age, additional studies with a larger number of oocytes are required to confirm the present results. Having access only to clinically discarded oocytes, we were limited to evaluating only those oocytes that failed to mature in vivo despite having been exposed to gonadotrophin stimulation and the ovulatory trigger of HCG. WIDER IMPLICATIONS OF THE FINDINGS To our knowledge, this is the first study investigating the effect of BPA on oocyte meiotic maturation, spindle morphology and chromosome alignment in human oocytes. Together with prior animal studies, the data support the negative influences of BPA on cell cycle progression, spindle architecture and chromosome organization during oocyte maturation. Furthermore, the increased rates of abnormal maturation in oocytes exposed to BPA may be relevant to our understanding of the decrease in fertility reported in the last decades. STUDY FUNDING/COMPETING INTEREST(S) This study was funded by the NIEHS Center Grant Pilot Project (P30-ES000002). R.M. was sponsored by a fellowship from the Environmental Health Fund, Israel and by the Frederick L. Hisaw Endowment, Harvard School of Public Health. There are no conflicts of interest. TRIAL REGISTRATION NUMBER n/a. PMID:23904465

  13. Effect of exposure duration of ovaries and oocytes at ambient temperature on parthenogenetic development of porcine follicular oocytes.

    PubMed

    Kim, Hyun-Jong; Choi, Sun-Ho; Son, Dong-Soo; Cho, Sang-Rae; Choe, Chang-Yong; Kim, Young-Keun; Han, Man-Hye; Ryu, Il-Sun; Kim, In-Cheul; Kim, Il-Hwa; Im, Kyung-Soon; Nagai, Takashi

    2006-10-01

    This study was conducted to evaluate the effects of exposing porcine ovaries to 30-33 C during transportation for 4 h and subsequently room temperature (25 C) for 6 h of storage on in vitro maturation (IVM) and subsequent parthenogenetic development of oocytes collected from the ovaries. After IVM, oocytes having a tight oopalsm membrane and no signs of degeneration were exposed to Dulbecco's phosphate-buffered saline (DPBS) with 7% ethanol (v/v) for 7 min to induce parthenogenetic activation. Moreover, we also determined whether exposure of the collected oocytes to room temperature for 1, 2 and 4 h in DPBS or porcine follicular fluid (pFF) affected parthenogenetic development. When porcine ovaries were stored after transportation, oocytes collected from the stored ovaries showed a significantly higher rate of degeneration after 65 h of IVM (58.4%) and a significantly lower rate of cleavage after parthenogenetic activation (40.1%) than oocytes collected from ovaries immediately after transportation (38.9% and 47.4%, respectively). However, there was no significant difference in developmental rates to the morula and blastocyst stages between these two groups (14.4% and 14.3%, respectively). The duration of preservation, 1, 2, and 4 h, of oocytes in DPBS did not affect parthenogenetic development. In contrast, when preserved for 4 h in pFF, the developmental rates of the oocytes were significantly decreased. This suggested that some factor(s) in follicular fluid affects the developmental rate of oocytes with the passage of time in ambient conditions. These results suggest that even after 6 h storage of ovaries, oocytes having normal morphology after IVM have the same rate of parthenogenetic development as oocytes collected from ovaries just after 4 h of transportation, except for a lower cleavage rate, and that exposure of oocytes to room temperature for 4 h in DPBS does not affect their parthenogenetic developmental competence. PMID:16807502

  14. Human oocyte cryopreservation: a valid alternative to embryo cryopreservation?

    Microsoft Academic Search

    Michael Tucker; Paula Morton; Juergen Liebermann

    2004-01-01

    Embryo cryopreservation has become an ethical necessity due to the way human in vitro fertilization (IVF) infertility therapy has developed. Limited embryonic implantation has by necessity driven IVF therapy to adopt ways to maximize the harvest of oocytes following ovarian hyperstimulation with its attendant risks. Collection of more oocytes has allowed more embryos to be generated to compensate for poor

  15. Xenopus laevis oocyte maturation is affected by metal chlorides.

    PubMed

    Marin, Matthieu; Slaby, Sylvain; Marchand, Guillaume; Demuynck, Sylvain; Friscourt, Noémie; Gelaude, Armance; Lemière, Sébastien; Bodart, Jean-François

    2015-08-01

    Few studies have been conducted using Xenopus laevis germ cells as oocytes, though these cells offer many advantages allowing both electrophysiological studies and morphological examination. Our aim was to investigate the effects of metal (cadmium, lead, cobalt and zinc) exposures using cell biology approaches. First, cell survival was evaluated with both phenotypical and electrophysiological approaches. Secondly, the effect of metals on oocyte maturation was assessed with morphological observations and electrophysiological recordings. From survival experiments, our results showed that metal chlorides did not affect cell morphology but strongly depolarized X. laevis oocyte resting potential. In addition, cadmium chloride was able to inhibit progesterone-induced oocyte maturation. By contrast, zinc, but also to a lesser extent cadmium, cobalt and lead, were able to enhance spontaneous oocyte maturation in the absence of progesterone stimulation. Finally, electrophysiological recordings revealed that some metal chlorides (lead, cadmium) exposures could disturb calcium signaling in X. laevis oocyte by modifying calcium-activated chloride currents. Our results demonstrated the high sensitivity of X. laevis oocytes toward exogenous metals such as lead and cadmium. In addition, the cellular events recorded might have a predictive value of effects occurring later on the ability of oocytes to be fertilized. Together, these results suggest a potential use of this cellular lab model as a tool for ecotoxicological assessment of contaminated fresh waters. PMID:25957907

  16. Oocyte competency is the key to embryo potential.

    PubMed

    Keefe, David; Kumar, Molly; Kalmbach, Keri

    2015-02-01

    The oocyte is the major determinant of embryo developmental competence in women. It delivers half the chromosomal complement to the embryo, but the maternal and paternal genomes are neither symmetrical nor equal in their contributions to embryo fate. Unlike the paternal genome, the maternal genome carries a heavy footprint of parental aging. Indeed, age is the single best predictor of reproductive outcome in women, and the oocyte is the locus of reproductive aging in women. The oocyte transmits not only the mother's nuclear but also her mitochondrial genome to the embryo, and mitochondrial DNA is known to be especially susceptible to aging. Morphological studies of the oocyte and its associated cumulus corona cells provide only marginal value in the assessment of embryo developmental potential. A number of novel technologies, however, have improved the noninvasive assessment of oocyte quality. Moreover, during maturation, the oocyte ejects half its homologous chromosomes into the first polar body and half its chromatids into the second polar body. Polar body DNA is remarkably similar to that of the oocyte, so analysis of polar body DNA provides a window into the oocyte's genome and telomeres, which may enhance prediction of embryo developmental competence. PMID:25639967

  17. Investigations into implantation failure in oocyte-donation recipients.

    PubMed

    Barri, Pedro N; Coroleu, Buenaventura; Clua, Elisabet; Tur, Rosa; Boada, Montserrat; Rodriguez, Ignacio

    2014-01-01

    In recent decades, the Western world has been experiencing a societal trend to prioritize the professional careers of women who postpone motherhood to about 40 years of age, when, unfortunately, natural reproductive potential declines. This is the reason why these women increasingly find it necessary to resort to oocyte donation to have a child. Thanks to the young age of the donors, the efficacy of oocyte donation is the highest of all assisted reproduction treatments and pregnancy rates achieved with this technique exceed 50%. Moreover, the large registries from ESHRE and ASRM show live birth rates close to this figure. However, there are patients who experience repeated failures in several oocyte-donation cycles, and so far oocyte-donation repeated implantation failure has not been clearly defined. This study analysed the results obtained from 2531 oocyte-donation cycles carried out in 1990 patients and defines oocyte-donation repeated implantation failure as failure to implant with more than two embryo transfers and more than four high-grade embryos transferred. This study observed this condition in 140 oocyte recipients (7%). Also, oocyte cohort size, uterine factors and systemic thrombophilias as important aetiological factors were identified were to offer new therapeutic strategies to patients. PMID:24268727

  18. PROTEIN UPTAKE IN THE OOCYTES OF THE CECROPIA MOTH

    Microsoft Academic Search

    BARBARA STAY

    2009-01-01

    The formation of yolk spheres in the oocyte of the cecropia moth, Hyalophora cecropia (L.), is known immunologically to result largely from uptake of a sex-limited blood protein. Recent electron microscope analyses of insect and other animal oocytes have demonstrated fine structural configurations consistent with uptake of proteins by pinocytosis. An electron microscope analysis of the cecropia ovary confirms the

  19. Human oocytes reprogram somatic cells to a pluripotent state

    Microsoft Academic Search

    Scott Noggle; Ho-Lim Fung; Athurva Gore; Hector Martinez; Kathleen Crumm Satriani; Robert Prosser; Kiboong Oum; Daniel Paull; Sarah Druckenmiller; Matthew Freeby; Ellen Greenberg; Kun Zhang; Robin Goland; Mark V. Sauer; Rudolph L. Leibel; Dieter Egli

    2011-01-01

    The exchange of the oocyte's genome with the genome of a somatic cell, followed by the derivation of pluripotent stem cells, could enable the generation of specific cells affected in degenerative human diseases. Such cells, carrying the patient's genome, might be useful for cell replacement. Here we report that the development of human oocytes after genome exchange arrests at late

  20. Reprogramming of Human Somatic Cells Using Human and Animal Oocytes

    Microsoft Academic Search

    Young Chung; Colin E. Bishop; Nathan R. Treff; Stephen J. Walker; Vladislav M. Sandler; Sandy Becker; Irina Klimanskaya; Wan-Song Wun; Randall Dunn; Rebecca M. Hall; Jing Su; Shi-Jiang Lu; Marc Maserati; Young-Ho Choi; Richard Scott; Anthony Atala; Ralph Dittman; Robert Lanza

    2009-01-01

    There is renewed interest in using animal oocytes to reprogram human somatic cells. Here we compare the re- programming of human somatic nuclei using oocytes obtained from animal and human sources. Comparative analysis of gene expression in morula-stage embryos was carried out using single-embryo transcriptome am- plification and global gene expression analyses. Genomic DNA fingerprinting and PCR analysis confirmed that

  1. Transport, meiotic arrest, and biphasic maturation of canine oocytes

    E-print Network

    Hanna, Carol Bailey McCormick

    2001-01-01

    oocytes to maintain them in the germinal vesicle stage (GV) allowing time to gain cytoplasmic competence. Oocytes were cultured in 0, 0.5, 1.0, or 1.5 mM dbcAMP for 20, 31 or 42 hours. Success was determined by retention of the GV. Results indicate...

  2. Gene amplification in the oocytes of dytiscid water beetles

    Microsoft Academic Search

    Joseph G. Gall; Herbert C. Macgregor; Mary Elizabeth Kidston

    1969-01-01

    A conspicuous mass of extrachromosomal DNA (Giardina's body) is found in oogonia and oocytes of Dytiscid water beetles. Since in older oocytes this DNA is associated with numerous nucleoli, it seemed probable that the ovary might contain extra copies of the genes for ribosomal RNA (rRNA). This hypothesis has been confirmed by centrifugation and molecular hybridization studies. —In Dytiscus marginalis

  3. Effect of lower than expected number of oocyte on the IVF results after oocyte-pickup

    PubMed Central

    Gonca, Süheyla; Gün, Ismet; Ovayolu, Ali; ?ilfeler, Dilek; Sofuo?lu, Kenan; Özdamar, Özkan; Yilmaz, Ali; Tunali, Gülden

    2014-01-01

    Objectives: To investigate whether a lower than expected number of oocyte after ?14 mm follicle aspiration during OPU has any effect on pregnancy outcomes Methods: This is a retrospective study done between 2010 and 2013 at the IVF Unit of the Zeynep Kamil Women and Children Diseases Education and Research Hospital, dealing with the medical records of infertile patients who underwent IVF cycle and controlled ovarian stimulation with long agonist or fix antogonist protocol. The patients included into the study were those diagnosed with a primary infertility, aged between 23 and 39, at a BMI of 22-28 kg/m2 and having received the first or second IVF treatment. Male factor, presence of uterine anomaly, patients with serious endometriosis and patients with low ovarian reserve were all excluded from the study. Typically, oocyte pick-up was performed in all the patients 35.5 hours after the hCG implementation. Single or double embryo transfer was performed, where available. Patients were classified into two groups. Group 1 consisted of those with no difference between ?14 mm aspirated follicle number and expected number of oocyte or with 1 missing number of oocyte at the most. Group 2 consisted of those with at least ?2 missing number of oocyte between aspirated follicle number and expected number of oocyte. Statistical analysis was performed using Student’s t test for continuous variables and chi-square test for categorical variables. Additionally, a Linear regression analysis was conducted between the total number of oocyte and pregnancy. Results: In total, 387 treatment cycles were included into the study. Group 1 consisted of 134 patients and Group 2 consisted of 252 patients. Antral follicle number (12.8 ± 4.3 and 14.5 ± 4.1, P = 0.0007), hCG day E2 value (1990.7 ± 1056.4 and 2515.2 ± 1332.7, P < 0.0001) and the the number of aspirated follicle during OPU (9.1 ± 4.4 and 13.7 ± 5.5, P < 0.0001) were significantly higher in Group 2; whereas on the other hand, daily gonadotropin dose (290.9 ± 79.9 and 273.4 ± 74.4, P = 0.034) and total gonadotropin doses (2545 ± 1031.8 and 2247.7 ± 901.9, P = 0.004) were significantly higher in Group 1. The pregnancy rate was significantly higher in Group 1 (29.1% and 19.4%, P = 0.041). No correlation was observed between the number of oocyte and pregnancy (r = 0.082, P = 0.107). Conclusions: The number of aspirated follicles during IVF treatment being higher than the collected number of oocyte leads to a statistically significant fall in the pregnancy rates. There is no correlation between the number of oocyte and pregnancy. PMID:25126190

  4. Deployable Wireless Camera Penetrators

    NASA Technical Reports Server (NTRS)

    Badescu, Mircea; Jones, Jack; Sherrit, Stewart; Wu, Jiunn Jeng

    2008-01-01

    A lightweight, low-power camera dart has been designed and tested for context imaging of sampling sites and ground surveys from an aerobot or an orbiting spacecraft in a microgravity environment. The camera penetrators also can be used to image any line-of-sight surface, such as cliff walls, that is difficult to access. Tethered cameras to inspect the surfaces of planetary bodies use both power and signal transmission lines to operate. A tether adds the possibility of inadvertently anchoring the aerobot, and requires some form of station-keeping capability of the aerobot if extended examination time is required. The new camera penetrators are deployed without a tether, weigh less than 30 grams, and are disposable. They are designed to drop from any altitude with the boost in transmitting power currently demonstrated at approximately 100-m line-of-sight. The penetrators also can be deployed to monitor lander or rover operations from a distance, and can be used for surface surveys or for context information gathering from a touch-and-go sampling site. Thanks to wireless operation, the complexity of the sampling or survey mechanisms may be reduced. The penetrators may be battery powered for short-duration missions, or have solar panels for longer or intermittent duration missions. The imaging device is embedded in the penetrator, which is dropped or projected at the surface of a study site at 90 to the surface. Mirrors can be used in the design to image the ground or the horizon. Some of the camera features were tested using commercial "nanny" or "spy" camera components with the charge-coupled device (CCD) looking at a direction parallel to the ground. Figure 1 shows components of one camera that weighs less than 8 g and occupies a volume of 11 cm3. This camera could transmit a standard television signal, including sound, up to 100 m. Figure 2 shows the CAD models of a version of the penetrator. A low-volume array of such penetrator cameras could be deployed from an aerobot or a spacecraft onto a comet or asteroid. A system of 20 of these penetrators could be designed and built in a 1- to 2-kg mass envelope. Possible future modifications of the camera penetrators, such as the addition of a chemical spray device, would allow the study of simple chemical reactions of reagents sprayed at the landing site and looking at the color changes. Zoom lenses also could be added for future use.

  5. Immune serum confers protection against syphilitic infection on hamsters.

    PubMed Central

    Azadegan, A A; Schell, R F; LeFrock, J L

    1983-01-01

    Pooled serum from hamsters immune to syphilitic infection conferred complete protection on recipient hamsters challenged with Treponema pallidum subsp. endemicum. Cutaneous lesions did not develop, and the recipients' lymph nodes weighed less than those of controls and contained no treponemes. Treponemicidal activity in the pooled immune serum was relatively high. When treponemes were incubated in immune serum and complement and the suspension was then inoculated into hamsters, recipients developed neither lesions nor enlarged lymph nodes teeming with treponemes. With hamsters already infected for several weeks, however, immune serum failed to impair or influence the progression of syphilis. Treponemes were eliminated only when immune serum was administered within a short time of syphilitic infection. These results demonstrate that hamsters develop an effective serum-mediated treponemicidal response, but this response is not sufficient to eliminate treponemes at the primary foci of infection. PMID:6352502

  6. Immunosuppressive Agents in Intracellular Infection: Besnoitiosis in Hamsters

    PubMed Central

    Wilson, H. R.; Frenkel, J. K.

    1971-01-01

    When tested for their activity in suppressing the acquisition of immunity during acute Besnoitia infection of hamsters, antilymphocyte serum (ALS), aminopterin, cyclophosphamide, cortisol, and whole-body irradiation were the most active agents and effectively blocked the development of immunity during 4 to 12 days of immunization. Actinomycin D and chlorambucil were moderately active, and nitrogen mustard, 6-mercaptopurine, and vinblastine exhibited slight immunosuppressive activity. Established immunity was especially labile to cortisol and cortisone administration with generalized Besnoitia relapse occurring consistently in all hamsters; this occurred infrequently during cyclophosphamide treatment. Focal relapse was seen in chronically irradiated and ALS-treated hamsters, but the location of the lesions differed. Irradiated hamsters had lesions in the lungs and brain, whereas ALS-treated hamsters showed splenic relapse. Acquisition of immunity was more sensitive to suppression than established immunity and did not necessarily parallel antibody development and vice versa, emphasizing the importance of cellular over humoral factors in immunity to this intracellular parasite. PMID:16558050

  7. Penetration of yawed projectiles

    SciTech Connect

    Reaugh, J.E.

    1990-10-08

    We used computer simulations and experiment to study the penetration of tungsten-alloy projectiles into a thick, armored steel target. These projectiles, with length-to-diameter ratios of 4, strike the target with severe yaws, up to 90{degree}(side-on-impact), such as might be induced in an originally longer projectile by a multiple-spaced plate array. In this study, we focus on the terminal ballistics of these projectiles and ignore how the yaw was induced. We found that the minimum penetration depth occurs at 90{degree}yaw. This case is well approximated by the two-dimensional plane-strain penetration of a side-on cylinder. The ratio of penetration depth to diameter, P:D, for this case is larger than that for a sphere because the plane-strain geometry lacks hoop stress, which is activated in axisymmetric geometry. A more surprising result of work is that the penetration at 60{degree} yaw is only slightly deeper than that of the side-on impact. 8 refs., 15 figs., 3 tabs.

  8. In Vitro Matured Oocytes Are More Susceptible than In Vivo Matured Oocytes to Mock ICSI Induced Functional and Genetic Changes

    PubMed Central

    Salian, Sujit Raj; Singh, Vikram Jeet; Kalthur, Guruprasad; Adiga, Satish Kumar

    2015-01-01

    Background Concerns regarding the safety of ICSI have been intensified recently due to increased risk of birth defects in ICSI born children. Although fertilization rate is significantly higher in ICSI cycles, studies have failed to demonstrate the benefits of ICSI in improving the pregnancy rate. Poor technical skill, and suboptimal in vitro conditions may account for the ICSI results however, there is no report on the effects of oocyte manipulations on the ICSI outcome. Objective The present study elucidates the influence of mock ICSI on the functional and genetic integrity of the mouse oocytes. Methods Reactive Oxygen Species (ROS) level, mitochondrial status, and phosphorylation of H2AX were assessed in the in vivo matured and IVM oocytes subjected to mock ICSI. Results A significant increase in ROS level was observed in both in vivo matured and IVM oocytes subjected to mock ICSI (P<0.05-0.001) whereas unique mitochondrial distribution pattern was found only in IVM oocytes (P<0.01-0.001). Importantly, differential H2AX phosphorylation was observed in both in vivo matured and IVM oocytes subjected to mock ICSI (P <0.001). Conclusion The data from this study suggests that mock ICSI can alter genetic and functional integrity in oocytes and IVM oocytes are more vulnerable to mock ICSI induced changes. PMID:25786120

  9. Male Syrian hamsters demonstrate a conditioned place preference for sexual behavior and female chemosensory stimuli

    E-print Network

    Sisk, Cheryl

    Male Syrian hamsters demonstrate a conditioned place preference for sexual behavior and female induce a CPP in male Syrian hamsters. As male Syrian hamsters are an animal model commonly used. Experiment 1 tested the prediction that male hamsters show a CPP for sexual behavior. Female chemosensory

  10. Sympathoadrenal System Differentially Affects Photoperiodic Changes in Humoral Immunity of Siberian Hamsters

    E-print Network

    Demas, Greg

    Hamsters (Phodopus sungorus) G. E. Demas*, D. L. Drazen², A. M. Jasnow³, T. J. Bartness³§ and R. J. Nelson, antibodies, catecholamines, norepinephrine. Abstract Siberian hamsters (Phodopus sungorus) rely catecholamines, to photoperiodic changes in immune function in male Siberian hamsters. In Experiment 1, hamsters

  11. Social interactions differentially affect reproductive and immune responses of Siberian hamsters

    E-print Network

    Demas, Greg

    Social interactions differentially affect reproductive and immune responses of Siberian hamsters in Siberian hamsters (Phodopus sungorus). Male and female hamsters were housed alone, in same-sex pairsM, and mitogen-stimulated splenocyte proliferation. Male hamsters housed with a female had increased testosterone

  12. Hypervelocity penetration of concrete

    Microsoft Academic Search

    A. Dawson; S. Bless; S. Levinson; B. Pedersen; S. Satapathy

    2008-01-01

    Experiments have been conducted with 6.25mm diameter tungsten rods striking concrete at 2.2km\\/s. Three concretes were used—one was 2.35g\\/cm3 and the other two were 2.27g\\/cm3. The erosion rates were measured to be T\\/?L=2.4–3.1 depending on the density of the concrete. This is greater than the hydrodynamic value, which shows that the strength of the penetrator is affecting the penetration. The cratering

  13. Survival of Pacific oyster, Crassostrea gigas, oocytes in relation to intracellular ice formation

    Microsoft Academic Search

    Liliana Salinas-Flores; S. L. Adams; D. A. Wharton; M. F. Downes; M. H. Lim

    2008-01-01

    The effect of IIF in Pacific oyster oocytes was studied using cryo and transmission electron microscopy (TEM). The viability of oocytes at each step of a published cryopreservation protocol was assessed in an initial experiment. Two major viability losses were identified; one when oocytes were cooled to ?35°C and the other when oocytes were plunged in liquid nitrogen. Although the

  14. Preliminary experience with human oocyte cryopreservation using 1,2-propanediol and sucrose

    Microsoft Academic Search

    Michael Tucker; Graham Wright; Paula Morton; Li Shanguo; Joe Massey; Hilton Kort

    1996-01-01

    Feasibility of cryopreservat ion of mature human oocytes using 1,2-propanediol and sucrose was studied initially utiliz- ing 1 and 2 day old unfertilized oocytes. Of these 285 aged oocytes 55% survived thawing, and 41% of 128 oocytes inseminated by single sperm intracytoplasmic injection (ICSI) fertilized normally. Limited embryonic development occurred in 51% of these embryos (n = 27) observed for

  15. Cellular, hormonal and ionic interactions related to induced and spontaneous oocyte maturation

    E-print Network

    Paris-Sud XI, Université de

    Cellular, hormonal and ionic interactions related to induced and spontaneous oocyte maturation A. W maturation of starfish oocytes are dis- cussed and compared. Spontaneous oocyte nuclear maturation occurs maturation is closely associated with loss of follicle cells from the oocyte. In the absence of calcium ions

  16. Regulatory contribution of heterotrimeric G-proteins to oocyte maturation in the sea urchin

    E-print Network

    Wessel, Gary M.

    Regulatory contribution of heterotrimeric G-proteins to oocyte maturation in the sea urchin-proteins regulate maturation in the sea urchin oocyte by identifying resident G-proteins in oocytes and eggs in both oocytes and eggs of the sea urchin. Three of them, Gai, Gaq, and Gas are present on the plasma

  17. Parthenogenic Blastocysts Derived from Cumulus-Free In Vitro Matured Human Oocytes

    Microsoft Academic Search

    Sohyun L. McElroy; James A. Byrne; Shawn L. Chavez; Barry Behr; Aaron J. Hsueh; Lynn M. Westphal; Renee A. Reijo Pera; Patrick Callaerts

    2010-01-01

    BackgroundApproximately 20% of oocytes are classified as immature and discarded following intracytoplasmic sperm injection (ICSI) procedures. These oocytes are obtained from gonadotropin-stimulated patients, and are routinely removed from the cumulus cells which normally would mature the oocytes. Given the ready access to these human oocytes, they represent a potential resource for both clinical and basic science application. However culture conditions

  18. Analysis of factors associated with multiple pregnancy in an oocyte donation programme

    Microsoft Academic Search

    Elisabet Clua; Rosa Tur; Buenaventura Coroleu; Montse Boada; Pere N. Barri; Anna Veiga

    2010-01-01

    The aim of this study is to identify the factors associated with multiple pregnancy in an oocyte donation programme. A retrospective study (2000–2007) of 945 synchronous cycles was performed. Two embryos were transferred in all cycles on day 2 after oocyte retrieval. All variables (egg donor and recipient age, number of inseminated oocytes, fertilized oocytes, cleaved embryos, good-quality embryos available,

  19. Fusome asymmetry and oocyte determination in Drosophila.

    PubMed

    Lin, H; Spradling, A C

    1995-01-01

    Germline cysts containing 16 interconnected cells (cystocytes) are produced at an early stage of Drosophila oogenesis by progenitor cells known as cystoblasts that undergo four synchronous rounds of incomplete division. During cyst formation, a region of specialized, spectrin-rich cytoplasm called the fusome traverses the intercellular connections (ring canals), linking individual cystocytes. Subsequently, 15 cystocytes begin to transport specific RNAs and other components into the remaining cell, the future oocyte. We used fusome-specific antibodies to characterize the early stages of cyst formation. During the first cystoblast division, a spherical mass of fusome material (the "spectrosome") was associated with only one pole of the mitotic spindle, revealing that this division is asymmetric. During the subsequent three divisions, the growing fusome always associated with the pole of each mitotic spindle that remained in the mother cell, and only extended through the newly formed ring canals after each division was completed. These observations suggest that fusomes help establish a system of directional transport between cystocytes that underlies oocyte determination. PMID:7758245

  20. CORTICAL CHANGES IN GROWING OOCYTES AND IN FERTILIZED OR PRICKED EGGS OF RANA PIPIENS

    PubMed Central

    Kemp, Norman E.; Istock, Nancy L.

    1967-01-01

    The folded cortex of the growing oocyte of the frog extends as microvilli into the substance of the developing vitelline membrane and, internal to the folds, possesses a layer of cortical granules. Free ribosomes, smooth-walled vesicles, coated vesicles, tubules, and electron-opaque granules are abundant in the peripheral zone of the cortex. Mitochondria, lipochondria, pigment granules, and electron-opaque granules are conspicuous between cortical granules and in the underlying endoplasm. Yolk platelets are restricted to the endoplasm. Cortical granules contain neutral and acid mucopolysaccharides, and possibly protein. In the mature oocyte, microvilli are withdrawn and the surface folds eliminated. Cortical granules now lie close to the plasma membrane, sometimes contacting it. Fertilization or pricking causes a wave of breakdown of cortical granules lasting 1–1½ min. Breakdown begins immediately after pricking but not until about 10–15 min after insemination, because the fertilizing sperm takes that long to penetrate the jelly and vitelline membrane. Cortical granules erupt through the surface and discharge their contents into the perivitelline space. Cortical craters left at sites of eruption soon disappear, and pseudopodial protrusions retract. By 30 min after insemination, the surface of the egg is relatively smooth. PMID:4226727

  1. Neurochemistry of olivocochlear neurons in the hamster.

    PubMed

    Reuss, Stefan; Disque-Kaiser, Ursula; Antoniou-Lipfert, Patricia; Gholi, Maryam Najaf; Riemann, Elke; Riemann, Randolf

    2009-04-01

    The present study was conducted to characterize the superior olivary complex (SOC) of the lower brain stem in the pigmented Djungarian hamster Phodopus sungorus. Using Nissl-stained serial cryostat sections from fresh-frozen brains, we determined the borders of the SOC nuclei. We also identified olivocochlear (OC) neurons by retrograde neuronal tracing upon injection of Fluoro-Gold into the scala tympani. To evaluate the SOC as a putative source of neuronal nitric oxide synthase (nNOS), arginine-vasopressin (AVP), oxytocin (OT), vasoactive intestinal polypeptide (VIP), or pituitary adenylate cyclase-activating polypeptide (PACAP) that were all found in the cochlea, we conducted immunohistochemistry on sections exhibiting retrogradely labeled neurons. We did not observe AVP-, OT-, or VIP-immunoreactivity, neither in OC neurons nor in the SOC at all, revealing that cochlear AVP, OT, and VIP are of nonolivary origin. However, we found nNOS, the enzyme responsible for nitric oxide synthesis in neurons, and PACAP in neuronal perikarya of the SOC. Retrogradely labeled neurons of the lateral olivocochlear (LOC) system in the lateral superior olive did not contain PACAP and were only infrequently nNOS-immunoreactive. In contrast, some shell neurons and some of the medial OC (MOC) system exhibited immunofluorescence for either substance. Our data obtained from the dwarf hamster Phodopus sungorus confirm previous observations that a part of the LOC system is nitrergic. They further demonstrate that the medial olivocochlear system is partly nitrergic and use PACAP as neurotransmitter or modulator. PMID:19301282

  2. Soil penetrometers and penetrability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil penetrometers are useful tools that measure the penetrability, or strength, of a soil. They can be as simple as a rod or shaft with a blunt or sharp end, or complicated mechanically driven instruments with digital data collection systems. Regardless of their design, soil penetrometers measure s...

  3. Jet penetration in glass

    SciTech Connect

    Moran, B.; Glenn, L.A.; Kusubov, A.

    1991-05-01

    We describe a phenomenological model which accounts for the mechanical response of glass to intense impulsive loading. An important aspect of this response is the dilatancy accompanying fracture. We have also conducted a number of experiments with 38.1-mm diameter precision shaped charges to establish the performance against various targets and to allow evaluation of our model. At 3 charge diameters standoff, the data indicate that both virgin and damaged glass offer better (Bernoulli-scaled) resistance to penetration than either of 4340 steel, or 6061-T6 aluminum alloy. Time-resolved measurements indicate two distinct phases of jet penetration in glass: An initial hydrodynamic phase, and a second phase characterized by a slower penetration velocity. Our calculations show that at early time, a crater is formed around the jet and only the tip of the undisturbed jet interacts with the glass. At late time the glass has collapsed on the jet and degraded penetration continues via a disturbed and fragmented jet.

  4. Single wall penetration equations

    NASA Technical Reports Server (NTRS)

    Hayashida, K. B.; Robinson, J. H.

    1991-01-01

    Five single plate penetration equations are compared for accuracy and effectiveness. These five equations are two well-known equations (Fish-Summers and Schmidt-Holsapple), two equations developed by the Apollo project (Rockwell and Johnson Space Center (JSC), and one recently revised from JSC (Cour-Palais). They were derived from test results, with velocities ranging up to 8 km/s. Microsoft Excel software was used to construct a spreadsheet to calculate the diameters and masses of projectiles for various velocities, varying the material properties of both projectile and target for the five single plate penetration equations. The results were plotted on diameter versus velocity graphs for ballistic and spallation limits using Cricket Graph software, for velocities ranging from 2 to 15 km/s defined for the orbital debris. First, these equations were compared to each other, then each equation was compared with various aluminum projectile densities. Finally, these equations were compared with test results performed at JSC for the Marshall Space Flight Center. These equations predict a wide variety of projectile diameters at a given velocity. Thus, it is very difficult to choose the 'right' prediction equation. The thickness of a single plate could have a large variation by choosing a different penetration equation. Even though all five equations are empirically developed with various materials, especially for aluminum alloys, one cannot be confident in the shield design with the predictions obtained by the penetration equations without verifying by tests.

  5. Cyclooxygenase-2 Expression in Hamster and Human Pancreatic Neoplasia1

    PubMed Central

    Yip-Schneider, Michele T; Savage, Jesse J; Hertzler, Dean A; Cummings, William O

    2006-01-01

    Abstract Cyclooxygenase-2 (COX-2) has been implicated in the development of gastrointestinal malignancies. The aim of the present study was to determine COX-2 expression/activity throughout stages of experimental and human pancreatic neoplasia. COX-2 immunohistochemistry was performed in pancreata of hamsters subjected to the carcinogen N-nitrosobis-(2-oxopropyl)amine (BOP) and in human pancreatic tumors. COX-2 activity was determined by prostaglandin E2 assay in tumor versus matched normal pancreatic tissues. The activity of the COX inhibitor sulindac was tested in the PC-1 hamster pancreatic cancer model. COX-2 expression was elevated in all pancreatic intraepithelial neoplasias (PanINs) and adenocarcinomas. In BOP-treated hamsters, there were significant progressive elevations in COX-2 expression throughout pancreatic tumorigenesis. In human samples, peak COX-2 expression occurred in PanIN2 lesions and remained moderately elevated in PanIN3 and adenocarcinoma tissues. COX-2 activity was significantly elevated in hamster and human pancreatic cancers compared to pair-matched normal pancreas. Furthermore, hamster pancreatic tumor engraftment/formation in the PC-1 hamster pancreatic cancer model was reduced 4.9-fold by oral administration of sulindac. Increased COX-2 expression is an early event in pancreatic carcinogeneses. The BOP-induced hamster carcinogenesis model is a representative model used to study the role of COX-2 in well-differentiated pancreatic tumorigenesis. COX inhibitors may have a role in preventing tumor engraftment/formation. PMID:16820089

  6. Biomechanics of penetrating trauma.

    PubMed

    Yoganandan, N; Pintar, F A

    1997-01-01

    It is well known that injuries and deaths due to penetrating projectiles have become a national and an international epidemic in Western society. The application of biomedical engineering to solve day-to-day problems has produced considerable advances in safety and mitigation/prevention of trauma. The study of penetrating trauma has been largely in the military domain where war-time specific applications were advanced with the use of high-velocity weapons. With the velocity and weapon caliber in the civilian population at half or less compared with the military counterpart, wound ballistics is a largely different problem in today's trauma centers. The principal goal of the study of penetrating injuries in the civilian population is secondary prevention and optimized emergency care after occurrence. A thorough understanding of the dynamic biomechanics of penetrating injuries quantifies missile type, caliber, and velocity to hard and soft tissue damage. Such information leads to a comprehensive assessment of the acute and long-term treatment of patients with penetrating injuries. A review of the relevant military research applied to the civilian domain and presentation of new technology in the biomechanical study of these injuries offer foundation to this field. Relevant issues addressed in this review article include introduction of the military literature, the need for secondary prevention, environmental factors including projectile velocity and design, experimental studies with biological tissues and physical models, and mathematical simulations and analyses. Areas of advancement are identified that enables the pursuit of biomechanics research in order to arrive at better secondary prevention strategies. PMID:9719858

  7. Strategies to support human oocyte development in vitro.

    PubMed

    Telfer, Evelyn E; McLaughlin, Marie

    2012-01-01

    Many young cancer patients are now being given the option to store ovarian cortical biopsies before undergoing potentially damaging chemo- or radiotherapy. This tissue mainly contains large numbers of immature primordial follicles. Currently the only option to restore fertility using this tissue is by transplantation which may not be a viable option for all patients. Greater options to realise the potential of this tissue to restore fertility could be achieved by the development of in vitro systems that support oocyte development. The ability to develop human oocytes from the most immature stages of follicles (primordial) through to maturation and fertilisation in vitro would revolutionise fertility preservation practice. This has been achieved in mouse where in vitro grown (IVG) oocytes from primordial follicles have resulted in the production of live offspring. However, developing IVG systems to support complete development of human oocytes has been more difficult because of differences in scale of timing and size. Our lab has been working on a multi-step culture system to support growth and development of bo-vine and human oocytes from primordial through to fully grown, using fresh and cryopreserved ovarian cortical tissue. This review outlines the approaches being taken to obtain complete in vitro development of human oocytes and strategies for assessing the health and viability of IVG oocytes. PMID:23417412

  8. Androgens promote the acquisition of maturation competence in bovine oocytes.

    PubMed

    Makita, Miho; Miyano, Takashi

    2015-06-20

    Recent studies in mice suggest that androgens are important for normal follicle development. However, there have been few reports concerning the action of androgens in the growth of oocytes from large animals. The purpose of this study was to determine the roles of androgens in bovine oocyte growth in vitro. Oocyte-granulosa cell complexes (OGCs) collected from 0.4-0.7 mm early antral follicles were cultured for 14 days with 17?-estradiol (E2) and a non-aromatizable androgen, dihydrotestosterone (DHT). We also examined the ability of an androgen receptor (AR) inhibitor, hydroxyflutamide, to antagonize the effect of androgens on the oocytes. During growth culture, the OGC structures collapsed in the medium with DHT alone, while in the presence of E2, the OGC structures were maintained. In the medium with both androgens and E2, the mean diameter of oocytes was increased from 95 ?m to around 120 ?m, larger than those grown with E2 alone (115 ?m). Also in the maturation culture, oocytes grown with androgens (A4 or DHT) and E2 showed higher percentages of metaphase II oocytes (63% or 69%, respectively) than those grown with E2 alone (32%). Moreover, these maturation rates were decreased by hydroxyflutamide in a dose-dependent manner. Immunostaining showed that ARs were expressed in oocytes and granulosa cells in early antral follicles, and the nuclei of granulosa cells showed intense AR expression. In conclusion, although E2 supports the OGC structure, additional androgens promote oocyte growth and their acquisition of meiotic competence via AR during in vitro growth culture. PMID:25754240

  9. Donor motivations, associated risks and ethical considerations of oocyte donation.

    PubMed

    Boutelle, Amy L

    2014-01-01

    Three decades after the first reported successful cases, oocyte donation continues to grow in popularity and regard as an established method to aid women in achieving their reproductive goals. As a result of the increased demand for donated oocytes, many young women in the U.S. volunteer to undergo complex medical procedures to donate their oocytes in return for financial compensation. To best care for these women before, during and after donation, it is important to explore donor characteristics and motivations, discuss the safety of the donation procedure and examine the ethical issues related to this process. PMID:24750650

  10. The dormant and the fully competent oocyte: comparing the transcriptome of human oocytes from primordial follicles and in metaphase II.

    PubMed

    Grøndahl, Marie Louise; Borup, Rehannah; Vikeså, Jonas; Ernst, Erik; Andersen, Claus Yding; Lykke-Hartmann, Karin

    2013-09-01

    Oocytes become enclosed in primordial follicles during fetal life and remain dormant there until activation followed by growth and meiotic resumption. Current knowledge about the molecular pathways involved in oogenesis is incomplete. This study identifies the specific transcriptome of the human oocyte in the quiescent state and at the pinnacle of maturity at ovulation. In silico bioinformatic comparisons were made between the transcriptome of human oocytes from dormant primordial follicles and that of human metaphase II (MII) oocytes and granulosa cells and unique gene expression profiles were identified as well as functional and pathway enrichments associated with the oocytes from the two developmental hallmarks. A total of 729 genes were highly enriched in oocytes from primodial follicles and 1456 genes were highly enriched in MII oocytes (>10-fold, P < 0.001) representing functional categories such as cell cycle regulation, DNA protection and epigenetics, with representative genes validated by qPCR analysis. Dominating canonical pathways in the oocytes from primordial follicles were androgen, estrogen receptor, glucocorticoid receptor and PI3K/AKT signaling (P < 0.001). In the MII, mitotic roles of polo-like kinases, estrogen receptor, JAK/Stat signaling (P < 0.001) and the ERK/MAPK (P < 0.01) signaling were enriched. Some of the highly differentially expressed genes were completely new in human reproduction (CDR1, TLC1A, UHRF2) while other genes [ABO, FOLR1 (folate receptor), CHRNA3 (nicotine receptor)] may relate to clinical observations as diverse as premature ovarian failure, folic acid deficiency and smoking affecting female fertility. The in silico analysis identified novel reproduction-associated genes and highlighted molecular mechanisms and pathways associated with the unique functions of the human oocyte in its two extremes during folliculogenesis. The data provides a fundamental basis for future functional studies in regulation of human oogenesis. PMID:23598597

  11. Lunar penetrator mission

    NASA Astrophysics Data System (ADS)

    Mizutani, H.; Kohno, M.; Fujimura, A.; Yamada, I.; Tanaka, S.; Hayakawa, M.

    1992-01-01

    Institute of Space and Astronautical Science (ISAS), Japan, plans to undertake a lunar mission, named LUNAR-A, which is to be launched in early 1996. The scientific objective of the mission is to explore the lunar interior using seismometry and heat-flow measurement toward better understanding of the origin and evolution of the moon. The M-V, the newest version of the Mu series launch vehicles now under development, is used to send a 550 kg of spacecraft to the lunar transfer orbit. Three penetrators (which are missile-shaped instrument carriers) are deployed from a spacecraft onto the lunar surface, and constitute a seismic and heat-flow measurement network of a larger span than the Apollo ALSEP network. The present paper describes the outline and scientific implications of the ISAS lunar penetrator mission.

  12. Effect of ?-linolenic acid on oocyte maturation and embryo development of prepubertal sheep oocytes.

    PubMed

    Ghaffarilaleh, Vahid; Fouladi-Nashta, Ali; Paramio, Maria-Teresa

    2014-09-15

    The purpose of this study was to evaluate the effect of omega-3 ?-linolenic acid (ALA) added to the IVM medium on embryo development of prepubertal sheep oocytes. Experiment 1 investigated the effect of ALA at different concentrations (0 [control], 50, 100, and 200 ?M) and DMSO (100 ?M) in IVM media on cumulus cell expansion and oocyte nuclear maturation and on synthesis of prostaglandins (PGE2 and PGF2?). Experiment 2 investigated the effects of ALA at different concentrations in the IVM medium on oocyte fertilization, cleavage, and developmental potential to blastocyst stage and changes in estradiol and progesterone concentrations in the spent IVM media. IVM oocytes were fertilized with frozen-thawed spermatozoa capacitated in a serum-free sperm medium. Presumptive zygotes were cultured 8 days in synthetic oviductal fluid (SOF) medium without serum. Blastocyst quality was assessed by counting total cell number and the number of apoptotic cells using Hoechst and Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. Nuclear maturation of oocytes and the number of fully expanded cumulus cells were reduced after treatment with 200 ?M of ALA compared with other groups (P ? 0.05). Supplementation with ALA increased both PGE2 and PGF2? concentrations in the spent media (P ? 0.05). No differences were observed in blastocyst development among control (12.2%) and 50, 100, and 200 ?M ALA groups (6.9%, 11.5% and 14.0%, respectively). However, the total cell number (46.50 ± 5.85, 67.94 ± 6.71, 45.20 ± 6.37, and 59.80 ± 5.51, respectively; P ? 0.05) and apoptotic cell number (6.45 ± 0.89, 2.48 ± 0.81, 4.02 ± 1.15, and 3.67 ± 1.15, respectively; P ? 0.05) were significantly improved. After IVM, estradiol concentration was lower and progesterone concentration was higher in ALA groups compared with the control group (P ? 0.05). In conclusion, these results revealed that ALA affects prepubertal sheep embryo quality associated with alteration of releasing reproductive hormones. PMID:25015785

  13. Choclo Virus Infection in the Syrian Golden Hamster

    PubMed Central

    Eyzaguirre, Eduardo J.; Milazzo, Mary Louise; Koster, Frederick T.; Fulhorst, Charles F.

    2009-01-01

    Andes virus and Choclo virus are agents of hantavirus pulmonary syndrome. Andes virus in hamsters almost always causes a disease that is pathologically indistinguishable from fatal hantavirus pulmonary syndrome. The purpose of this study was to assess the pathogenicity of Choclo virus in hamsters. None of 18 hamsters infected with Choclo virus exhibited any symptom of disease. No evidence of inflammation or edema was found in the lungs of the 10 animals killed on days 7, 9, 11, 13, and 16 post-inoculation or in the lungs of the 8 animals killed on day 28 post-inoculation; however, hantavirus antigen was present in large numbers of endothelial cells in the microvasculature of the lungs of the animals killed on days 7, 9, 11, and 13 post-inoculation. These results suggest that infection in the microvasculature of lung tissue alone does not result in the life-threatening pulmonary edema in hamsters infected with Andes virus. PMID:18385367

  14. Oocyte maturation: a story of arrest and release.

    PubMed

    Sen, Aritro; Caiazza, Francesco

    2013-01-01

    The release of a mature healthy egg for fertilization is the center of the entire reproductive process. From the time of embryonic development till fertilization, the oocyte undergoes several stop-and-go periods. In most animals, oocytes are held in meiotic arrest in prophase I prior to ovulation. The ovulatory luteinizing hormone (LH) surge promotes the resumption of meiosis of the arrested oocytes and their progression through the second meiotic cycle, only to be arrested again at metaphase II until fertilization. This review addresses the underlying mechanisms involved in maintaining the oocyte in meiotic arrest as well as the signaling pathways responsible for releasing it from the arrested phase just prior to ovulation until the completion of meiosis at the time of fertilization. PMID:23277062

  15. Transport, meiotic arrest, and biphasic maturation of canine oocytes 

    E-print Network

    Hanna, Carol Bailey McCormick

    2001-01-01

    Assisted reproduction is undeveloped in the canine compared to most domestic mammalian species. One of the contributing reasons is the inefficiency of in vitro maturation (IVM) of the canine oocyte. This project was designed to examine several...

  16. OOCYTE DIFFERENTIATION AND VITELLOGENESIS IN THE ROACH PERIPLANETA AMERICANA

    PubMed Central

    Anderson, Everett

    1964-01-01

    The ovary of the roach Periplaneta americana has been studied by techniques of light and electron microscopy. Each ovariole (panoistic type) contains a linear array of oocytes in varying stages of development. Newly formed oocytes become encased by a layer of follicle cells and begin pinocytosis. All subsequent growth stages of the oocytes are dependent, in part, on this phenomenon. All of the pinocytotic caveolae show an unique surface modification; i.e., on their internal surface they have an amorphous or filamentous substance and their external surface is studded with many fine radially oriented spike-like projections. The pinosomes of early oocytes do not contain a demonstrable internal structure; they are thought to contain nutritive substances for the developing oocytes rather than yolk precursors. When the oocyte enters its last stage of growth, characterized by yolk deposition, the caveolae become filled with a dense material which is thought to be the precursors of yolk. Hence the conclusion is drawn that yolk formation is independent of any cytoplasmic organelle system of the oocyte and that the precursors of this deutoplasmic substance are manufactured outside the ovary and are internalized by the process of pinocytosis. Under the phase-contrast microscope the nucleoli of early oocytes are large irregular masses and show the phenomenon of nucleolar emission (fragmentation). These "emissions" become randomly dispersed in the nucleoplasm and some of them come to be intimately associated with the fenestrated nuclear envelope. After this process ceases, the main nucleolar mass becomes vacuolated. Electron micrographs suggest that the constituent particles of the nucleolar emissions migrate from the nucleus through patent pores of the nuclear envelope. PMID:14105205

  17. Receptor-mediated Endocytosis in the Caenorhabditis elegans Oocyte

    Microsoft Academic Search

    Barth Grant; David Hirsh

    1999-01-01

    The Caenorhabditis elegans oocyte is a highly amenable system for forward and reverse genetic analysis of receptor-mediated endocytosis. We describe the use of transgenic strains expressing a vitellogenin::green fluorescent protein (YP170::GFP) fusion to monitor yolk endocytosis by the C. elegans oocyte in vivo. This YP170::GFP reporter was used to assay the functions of C. elegans predicted proteins homologous to vertebrate

  18. Natriuretic peptides stimulate oocyte meiotic resumption in bovine.

    PubMed

    Cesaro, Matheus P De; Macedo, Mariana P; Santos, Joabel T; Rosa, Paulo R A; Ludke, Charles A; Rissi, Vitor B; Gasperin, Bernardo G; Gonçalves, Paulo B D

    2015-08-01

    The aim of the present study was to evaluate the expression of mRNA encoding natriuretic peptides (NPs) and their receptors in the cumulus-oocyte complex in cattle, a monovular mammalian species, and also to investigate the role of NPs in oocyte meiotic resumption in vitro. mRNA was observed for the NP precursor type-A (NPPA), type-C (NPPC), NP receptor-1 (NPR-1), receptor-2 (NPR-2) and receptor-3 (NPR-3) in bovine cumulus cells, and NPR-2 mRNA was observed in oocytes. These results are different from those obtained in mouse and pig models. The effects of NPPA, NP precursor type-B (NPPB) and NPPC on the resumption of arrested meiosis maintained by forskolin were studied at three different doses (10, 100 and 1000nM) with a 12h culture system. The germinal vesicle breakdown rates were greater (P?0.05) in oocytes that were cultured in the presence of one or a combination of NPs (from 44% to 73%) than the negative control (from 24% to 27%). Additionally, it was demonstrated that the concentration of cyclic guanosine 3',5'-monophosphate (cGMP) is increased by NPPA and NPPC in oocytes and cumulus cells after 3h of in vitro maturation. However, in both groups, the concentration of cyclic adenosine 3',5'-monophosphate (cAMP) in the oocyte did not increase between 3 and 6h of culture, even when forskolin was used. In summary, we observed the presence of mRNA for NPs and their receptors in the bovine cumulus-oocyte complex and demonstrated that, in vitro, NPPA, NPPB and NPPC stimulate oocyte meiotic resumption in a monovular species. PMID:26051611

  19. Factors affecting in vitro maturation of alpaca (Lama paco) oocytes.

    PubMed

    Leisinger, Ca; Coffman, Ea; Coutinho da Silva, Ma; Forshey, Bs; Pinto, Crf

    2014-11-10

    The present study utilized a 2×2×2 factorial design examining age (old vs. young), follicle size (?2mm vs. <2mm) and media supplementation (with or without fetal bovine serum [FBS]) to determine factors that might affect in vitro maturation of alpaca oocytes. We hypothesized that oocytes collected from follicles ?2mm from young alpacas and incubated in maturation media supplemented with FBS would have greater maturation rates than those incubated in any other factorial combination. Oocytes were collected from the ovaries of 11 young alpacas (<10 years old) and 14 old alpacas (>11 years old). Oocytes were classified as morphologically normal oocytes (MNO) and deemed suitable for incubation if ?3 compact layers of cumulus cells and a homogeneous, evenly granulated cytoplasm were observed. Oocytes from each group of follicle sizes were incubated separately and halves of each group were randomly divided and incubated 24h in chemically defined maturation media with or without 10% FBS. Maturation was defined as the visualization of a polar body at the end of the incubation period. Overall, a greater proportion of MNO were collected from follicles ?2mm than that obtained from smaller follicles, 55% (136/247) vs. 29.6% (162/547), respectively (P<0.05). A greater proportion of oocytes reached maturation when collected from ?2mm follicles 36% (49/136) than from <2mm follicles 8% (13/162) (P<0.05). For oocytes obtained from ?2mm follicles of old alpacas, a greater proportion reached maturation when incubated in media supplemented with FBS than when incubated without FBS; 57.6% (19/33) vs. 18.2% (6/33), respectively (P<0.05). PMID:25261077

  20. Regulation of tonic gonadotropin release in prepubertal female hamsters

    SciTech Connect

    Smith, S.G.; Matt, K.S.; Prestowitz, W.F.; Stetson, M.H.

    1982-04-01

    Basal serum gonadotropin levels were monitored weekly in female hamsters from birth to 10 weeks of age. Hamsters raised on three different photoperiods presented uniform pre- and postpubertal patterns of serum LH and FSH, suggesting that gonadotropin release in the young hamster occurs independently of ambient photoperiod. In all groups, serum LH levels increased gradually in animals up to 4 weeks of age, after which levels plateaued at 50--100 ng/ml. Serum FSH was markedly elevated in 2- and 3-week-old hamsters (800--1200 ng/ml), but remained at 200--400 ng/ml in all other groups. We next examined the change in the responsiveness of the pituitary to exogenous gonadotropin-releasing hormone (GnRH) challenge. Female hamsters 2 days of age failed to respond to any dose (0.025--1000 ng) of GnRH, while 10-day old females responded in typical dose-dependent fashion. GnRH-stimulated LH release first occurred in 6-day-old hamsters and was maximal by day 9, whereas FSH release first occurred on day 8 and was maximal by day 9. The prepubertal pattern of gonadotropin release can, in part, be explained on the basis of the development of pituitary GnRH sensitivity, which occurs independently of photoperiod.

  1. Regulation of hamster splenocyte reactivity to concanavalin A during pregnancy

    SciTech Connect

    Weppner, W.A.; Coggin, J.H. Jr.

    1980-08-15

    The survival to term of mammalian fetuses regardless of their expression of paternal or embryonic developmental antigens suggests that some alteration in the immune capabilities of a female occur during pregnancy. The immunocompetence of female Syrian golden hamsters during pregnancy was investigated with respect to the blastogenic response of spleen cells to the T-cell mitogen concanavalin A (Con A). The blastogenic response of spleen cells from pregnant hamsters during mid- or late gestation is 10% of that observed for spleen cells from age-matched, virgin female animals. The spleen cells from pregnant hamsters are not capable of suppressing the proliferative response of spleen cells from virgin females to Con A. However, the serum from pregnant hamsters, in comparison with serum from virgin female animals, is capable of reducing this mitogenic response. Extensive washing of the splenocytes from pregnant hamsters does reduce the degree of suppression. These results suggest that the hamster is an excellent animal model for the investigation of the mechanism(s) of immune regulation that operate during pregnancy.

  2. Syrian Hamster model of postmenopausal hypercholesterolemia atherosclerosis and the development of plaques as imaged by high field MRI

    E-print Network

    McQuade, D. Tyler

    Syrian Hamster model of postmenopausal hypercholesterolemia atherosclerosis and the development of flaxseed in a hamster model of postmenopausal atherosclerosis. The focus is to examine in vivo identification of plaques in cerebral arteries and aortas of overiectomized (ovx) hamsters with endogenous

  3. The transcriptome of a human polar body accurately reflects its sibling oocyte.

    PubMed

    Reich, Adrian; Klatsky, Peter; Carson, Sandra; Wessel, Gary

    2011-11-25

    Improved methods are needed to reliably and accurately evaluate oocyte quality prior to fertilization and transfer into the woman of human embryos created through in vitro fertilization (IVF). All oocytes that are retrieved and matured in culture are exposed to sperm with little in the way of evaluating the oocyte quality. Furthermore, embryos created through IVF are currently evaluated for developmental potential by morphology, a criterion lacking in quantitation and accuracy. With the recent successes in oocyte vitrification and storage, clear metrics are needed to determine oocyte quality prior to fertilizing. The first polar body (PB) is extruded from the oocyte before fertilization and can be biopsied without damaging the oocyte. Here, we tested the hypothesis that the PB transcriptome is representative of that of the oocyte. Polar body biopsy was performed on metaphase II (MII) oocytes followed by single-cell transcriptome analysis of the oocyte and its sibling PB. Over 12,700 unique mRNAs and miRNAs from the oocyte samples were compared with the 5,431 mRNAs recovered from the sibling PBs (5,256 shared mRNAs or 97%, including miRNAs). The results show that human PBs reflect the oocyte transcript profile and suggests that mRNA detection and quantification through high-throughput quantitative PCR could result in the first molecular diagnostic for gene expression in MII oocytes. This could allow for both oocyte ranking and embryo preferences in IVF applications. PMID:21953461

  4. The Transcriptome of a Human Polar Body Accurately Reflects Its Sibling Oocyte*

    PubMed Central

    Reich, Adrian; Klatsky, Peter; Carson, Sandra; Wessel, Gary

    2011-01-01

    Improved methods are needed to reliably and accurately evaluate oocyte quality prior to fertilization and transfer into the woman of human embryos created through in vitro fertilization (IVF). All oocytes that are retrieved and matured in culture are exposed to sperm with little in the way of evaluating the oocyte quality. Furthermore, embryos created through IVF are currently evaluated for developmental potential by morphology, a criterion lacking in quantitation and accuracy. With the recent successes in oocyte vitrification and storage, clear metrics are needed to determine oocyte quality prior to fertilizing. The first polar body (PB) is extruded from the oocyte before fertilization and can be biopsied without damaging the oocyte. Here, we tested the hypothesis that the PB transcriptome is representative of that of the oocyte. Polar body biopsy was performed on metaphase II (MII) oocytes followed by single-cell transcriptome analysis of the oocyte and its sibling PB. Over 12,700 unique mRNAs and miRNAs from the oocyte samples were compared with the 5,431 mRNAs recovered from the sibling PBs (5,256 shared mRNAs or 97%, including miRNAs). The results show that human PBs reflect the oocyte transcript profile and suggests that mRNA detection and quantification through high-throughput quantitative PCR could result in the first molecular diagnostic for gene expression in MII oocytes. This could allow for both oocyte ranking and embryo preferences in IVF applications. PMID:21953461

  5. Suppression of hamster lymphocyte reactivity to simian virus 40 tumor surface antigens by spleen cells from pregnant hamsters

    SciTech Connect

    Weppner, W.A.; Adkinson, L.R.; Coggin, J.H.Jr

    1980-09-01

    SV40-transformed tumor cells in hamsters have been found to have cell surface antigens cross-reactive with antigens temporally expressed on fetal tissues. Using a lymphocyte transformation assay, spleen cells from pregnant hamsters were found to be incapable of responding to preparations of either hamster fetal tissue or SV40-transformed cells. However, a suppressor component can be demonstrated in spleen cell populations of both primi-and multiparous hamsters during pregnancy that is capable of reducing the response of lymphocytes sensitized against SV40 tumor-associated antigens. The degree of suppression is proportional to the ratio of responder cells to spleen cells from pregnant animals. These results suggest there is a subpopulation of spleen cells involved in immunoregulation during pregnancy that has the ability to suppress the reactivity of lymphocytes sensitized against SV40-associated oncofetal antigens.

  6. The Role of Mitochondria from Mature Oocyte to Viable Blastocyst

    PubMed Central

    2013-01-01

    The oocyte requires a vast supply of energy after fertilization to support critical events such as spindle formation, chromatid separation, and cell division. Until blastocyst implantation, the developing zygote is dependent on the existing pool of mitochondria. That pool size within each cell decreases with each cell division. Mitochondria obtained from oocytes of women of advanced reproductive age harbor DNA deletions and nucleotide variations that impair function. The combination of lower number and increased frequency of mutations and deletions may result in inadequate mitochondrial activity necessary for continued embryo development and cause pregnancy failure. Previous reports suggested that mitochondrial activity within oocytes may be supplemented by donor cytoplasmic transfer at the time of intracytoplasmic sperm injection (ICSI). Those reports showed success; however, safety concerns arose due to the potential of two distinct populations of mitochondrial genomes in the offspring. Mitochondrial augmentation of oocytes is now reconsidered in light of our current understanding of mitochondrial function and the publication of a number of animal studies. With a better understanding of the role of this organelle in oocytes immediately after fertilization, blastocyst and offspring, mitochondrial augmentation may be reconsidered as a method to improve oocyte quality. PMID:23766762

  7. Egg sharing for assisted conception: a window on oocyte quality.

    PubMed

    Faddy, Malcolm; Gosden, Roger; Ahuja, Kamal; Elder, Kay

    2011-01-01

    The steep decline in both natural fertility and success after assisted reproduction treatment with increasing maternal age is universally recognized. Large variations in the developmental competence of oocytes collected are seen during assisted cycles,and a link between the biological competence of oocytes retrieved and age has been confirmed. Patients who require donated oocytes can benefit from egg sharing programmes, in which a proportion of oocytes collected from selected patients aged 35 years undergoing conventional assisted reproduction treatment are shared with a matched recipient. The reproductive outcomes of the egg provider and recipient can thus be compared to quantify the significance of oocyte quality. Data gathered from two comparable treatment centres resulted in 285 pairs of egg sharing providers and their recipients that could be analysed statistically. The chief finding was donor pregnancy as a predictor of recipient pregnancy given embryo transfer (odds ratio 2.15, 95% confidence interval 1.33–3.46, P ? 0.002), despite an appreciably higher mean age of the recipients. The probability of a recipient pregnancy increased by almost 0.2. Such results strongly indicate the key importance of oocyte quality for a successful clinical outcome in egg sharing practices and assisted reproduction treatment more generally. PMID:21126913

  8. Frequency of Aneuploidy Related to Age in Porcine Oocytes

    PubMed Central

    Musilova, Petra; Pavlok, Antonin; Kubelka, Michal; Motlik, Jan; Rubes, Jiri; Anger, Martin

    2011-01-01

    It is generally accepted that mammalian oocytes are frequently suffering from chromosome segregation errors during meiosis I, which have severe consequences, including pregnancy loss, developmental disorders and mental retardation. In a search for physiologically more relevant model than rodent oocytes to study this phenomenon, we have employed comparative genomic hybridization (CGH), combined with whole genome amplification (WGA), to study the frequency of aneuploidy in porcine oocytes, including rare cells obtained from aged animals. Using this method, we were able to analyze segregation pattern of each individual chromosome during meiosis I. In contrast to the previous reports where conventional methods, such as chromosome spreads or FISH, were used to estimate frequency of aneuploidy, our results presented here show, that the frequency of this phenomenon was overestimated in porcine oocytes. Surprisingly, despite the results from human and mouse showing an increase in the frequency of aneuploidy with advanced maternal age, our results obtained by the most accurate method currently available for scoring the aneuploidy in oocytes indicated no increase in the frequency of aneuploidy even in oocytes from animals, whose age was close to the life expectancy of the breed. PMID:21556143

  9. Human oocytes. Error-prone chromosome-mediated spindle assembly favors chromosome segregation defects in human oocytes.

    PubMed

    Holubcová, Zuzana; Blayney, Martyn; Elder, Kay; Schuh, Melina

    2015-06-01

    Aneuploidy in human eggs is the leading cause of pregnancy loss and several genetic disorders such as Down syndrome. Most aneuploidy results from chromosome segregation errors during the meiotic divisions of an oocyte, the egg's progenitor cell. The basis for particularly error-prone chromosome segregation in human oocytes is not known. We analyzed meiosis in more than 100 live human oocytes and identified an error-prone chromosome-mediated spindle assembly mechanism as a major contributor to chromosome segregation defects. Human oocytes assembled a meiotic spindle independently of either centrosomes or other microtubule organizing centers. Instead, spindle assembly was mediated by chromosomes and the small guanosine triphosphatase Ran in a process requiring ~16 hours. This unusually long spindle assembly period was marked by intrinsic spindle instability and abnormal kinetochore-microtubule attachments, which favor chromosome segregation errors and provide a possible explanation for high rates of aneuploidy in human eggs. PMID:26045437

  10. Penetrating Fire Extinguisher

    NASA Technical Reports Server (NTRS)

    1985-01-01

    When Feecon Corporation, a manufacturer of fire protection systems, needed a piercing nozzle for larger aircraft, they were assisted by Kennedy Space Center who provided the company with a fire extinguisher with a hard pointed tip that had been developed in case of an orbiter crash landing. The nozzle can penetrate metal skins of aircraft, trains, etc. Feecon obtained a license and now markets its cobra ram piercing nozzle to airport firefighters. Its primary advantage is that the nozzle can be held in one spot during repeated blows of the ram. *This product has been discontinued and is no longer commercially available.

  11. Deep penetration calculations. [LMFBR

    SciTech Connect

    Thompson, W.L.; Deutsch, O.L.; Booth, T.E.

    1980-04-01

    Several Monte Carlo techniques are compared in the transport of neutrons of different source energies through two different deep-penetration problems each with two parts. The first problem involves transmission through a 200-cm concrete slab. The second problem is a 90/sup 0/ bent pipe jacketed by concrete. In one case the pipe is void, and in the other it is filled with liquid sodium. Calculations are made with two different Los Alamos Monte Carlo codes: the continuous-energy code MCNP and the multigroup code MCMG.

  12. Human oocytes express ATP-sensitive K+ channels

    PubMed Central

    Du, Qingyou; Jovanovi?, Sofija; Sukhodub, Andriy; Barratt, Evelyn; Drew, Ellen; Whalley, Katherine M.; Kay, Vanessa; McLaughlin, Marie; Telfer, Evelyn E.; Barratt, Christopher L.R.; Jovanovi?, Aleksandar

    2010-01-01

    BACKGROUND ATP-sensitive K+ (KATP) channels link intracellular metabolism with membrane excitability and play crucial roles in cellular physiology and protection. The KATP channel protein complex is composed of pore forming, Kir6.x (Kir6.1 or Kir6.2) and regulatory, SURx (SUR2A, SUR2B or SUR1), subunits that associate in different combinations. The objective of this study was to determine whether mammalian oocytes (human, bovine, porcine) express KATP channels. METHODS Supernumerary human oocytes at different stages of maturation were obtained from patients undergoing assisted conception treatments. Bovine and porcine oocytes in the germinal vesicle (GV) stage were obtained by aspirating antral follicles from abattoir-derived ovaries. The presence of mRNA for KATP channel subunits was determined using real-time RT–PCR with primers specific for Kir6.2, Kir6.1, SUR1, SUR2A and SUR2B. To assess whether functional KATP channels are present in human oocytes, traditional and perforated patch whole cell electrophysiology and immunoprecipitation/western blotting were used. RESULTS Real-time PCR revealed that mRNA for Kir6.1, Kir6.2, SUR2A and SUR2B, but not SUR1, were present in human oocytes of different stages. Only SUR2B and Kir6.2 mRNAs were detected in GV stage bovine and porcine oocytes. Immunoprecipitation with SUR2 antibody and western blotting with Kir6.1 antibody identified bands corresponding to these subunits in human oocytes. In human oocytes, 2,4-dinitrophenol (400 µM), a metabolic inhibitor known to decrease intracellular ATP and activate KATP channels, increased whole cell K+ current. On the other hand, K+ current induced by low intracellular ATP was inhibited by extracellular glibenclamide (30 µM), an oral antidiabetic known to block the opening of KATP channels. CONCLUSIONS In conclusion, mammalian oocytes express KATP channels. This opens a new avenue of research into the complex relationship between metabolism and membrane excitability in oocytes under different conditions, including conception. PMID:20847183

  13. Cryopreservation of Mammalian Oocytes by Using Sugars: Intra- and extracellular raffinose with small amounts of dimethylsulfoxide yields high cryosurvival, fertilization, and development rates

    PubMed Central

    Eroglu, Ali

    2009-01-01

    Accumulation of intra- and extracellular sugars such as trehalose, glucose, and raffinose is central to survival strategies of a variety of organisms coping with extreme conditions including freezing and almost complete drying. The objective of the present study was to investigate the potential application of intra- and extracellular raffinose in combination with low concentrations of dimethylsulfoxide (Me2SO) to mammalian oocyte cryopreservation. To this end, the fertilization and embryonic development of cryopreserved metaphase II (M II) mouse oocytes were studied in comparison to unfrozen controls. For cryopreservation, M II oocytes were microinjected with 0.1 M raffinose, and then cooled to -196°C in the presence of either 0.3 M raffinose and 0.5 M Me2SO (cryopreservation group 1) or 0.3 M raffinose and 1.0 M Me2SO (cryopreservation group 2). The control groups included untreated oocytes (untreated control) and oocytes microinjected with raffinose, but not frozen (injection control). The post-thaw survival rates were 83.9% and 80.6% for the cryopreservation group 1 and 2, respectively. The fertilization and blastocyst rates in the cryopreservation group 1 (90.0% and 77.8%, respectively) and 2 (94.6% and 72.5%, respectively) were also high and similar to the ones of the injection controls (97.8% and 78.5%, respectively) and untreated controls (98.8% and 83.6%, respectively). These results are consistent with the findings of our earlier studies and support the use of sugars as intra- and extracellular cryoprotectants. Furthermore, the results of the present study indicate that the presence of intra- and extracellular sugars alleviates high concentrations of conventional penetrating cryoprotectants, and thus minimizes their toxicity. PMID:19596315

  14. Successful pregnancy and delivery after ICSI with artificial oocyte activation by calcium ionophore in in-vitro matured oocytes: a case report.

    PubMed

    Kim, Jun-Woo; Yang, Seong-Ho; Yoon, San-Hyun; Kim, Sang-Don; Jung, Jae-Hoon; Lim, Jin-Ho

    2015-04-01

    The achievement of a successful pregnancy and delivery after oocyte activation with calcium ionophore is reported in a couple having low fertilization rates after intracytoplasmic sperm injection (ICSI) of in-vitro matured oocytes. A couple, in which the wife had polycystic ovary syndrome and the husband had moderate oligoteratozoospermia, showed a low fertilization rate in a previous in-vitro maturation cycle (2/11 [18.2%]). The most likely cause of complete fertilization failure or low fertilization rates is failure of oocyte activation. Therefore, artificial oocyte activation by calcium ionophore was combined with ICSI to achieve viable fertilized oocytes. Oocytes were stimulated with calcium ionophore for 30?min after ICSI. The fertilization rate of oocytes activated with calcium ionophore (13/15 [86.7%] and 7/9 [77.8%]) was higher than that of the non-activated oocytes. In the latest cycle, three embryos derived from the activated oocytes were transferred into the uterus on day 3. Subsequently, two gestational sacs were identified on ultrasound. The patient delivered dizygotic twins (girl 2260?g and boy 2760?g) at 35 weeks and 6 days gestation by caesarean section. This result suggests that calcium ionophore could be useful for oocyte fertilization in couples with low fertilization rates after ICSI of in-vitro matured oocytes. PMID:25592974

  15. Monolithic ballasted penetrator

    DOEpatents

    Hickerson, Jr., James P. (Cedar Crest, NM); Zanner, Frank J. (Sandia Park, NM); Baldwin, Michael D. (Albuquerque, NM); Maguire, Michael C. (Worcester, MA)

    2001-01-01

    The present invention is a monolithic ballasted penetrator capable of delivering a working payload to a hardened target, such as reinforced concrete. The invention includes a ballast made from a dense heavy material insert and a monolithic case extending along an axis and consisting of a high-strength steel alloy. The case includes a nose end containing a hollow portion in which the ballast is nearly completely surrounded so that no movement of the ballast relative to the case is possible during impact with a hard target. The case is cast around the ballast, joining the two parts together. The ballast may contain concentric grooves or protrusions that improve joint strength between the case and ballast. The case further includes a second hollow portion; between the ballast and base, which has a payload fastened within this portion. The penetrator can be used to carry instrumentation to measure the geologic character of the earth, or properties of arctic ice, as they pass through it.

  16. Investigation of anomalous penetration

    NASA Astrophysics Data System (ADS)

    Young, Robert D.; Littlefield, David L.; Horie, Y.

    1994-07-01

    Numerical experiments were performed as part of an ongoing effort to understand the Russian claims of anomalous or super-deep penetration. The claim is that unusually large penetration to particle diameter ratios are obtained for a few particles when a large number of particles bombard a solid target. As a first step in this process, cumulation effects were examined to determine their potential mechanistic role in the interaction. Two-dimensional hydrocode analyses were used to simulate simultaneous particle impact into a semi-infinite target. As a consequence of the chosen axisymmetric model, impacting particle were rings, collapsing to a single sphere when the modeled particles were centered on the axis of symmetry. Results of the analysis indicate that when the distance between particle centers is nonzero, cylindrical shock waves form which have propagation components both coverging to an diverging from the axis of symmetry. Energy density cumulation results due to the decreasing volume of converging shock waves approaching the symmetry axis. Numerical results show a four fold increase in shock wave amplitude at the time of convergence with respect to the shock amplitude produced at impact. Surprisingly, the amplitude at the time of the converged shock is only a weak function of the particle distance from the symmetry axis. As a result of the convergence, a tunnel forms along the axis of symmetry which, upon release, changes phase to liquid and vapor which possesses high velocity components. This phenomenon was observed at impact velocities as low as 3 km/s.

  17. Methylation of liver DNA guanine in hamsters given hydrazine.

    PubMed

    Bosan, W S; Shank, R C

    1983-09-15

    Formation of 7-methylguanine and O6-methylguanine in liver DNA was measured 24 hr after administration of various single oral doses of 15 to 120 mg hydrazine/kg body wt to Syrian golden hamsters, and at various times up to 96 hr after a single oral dose of 90 mg hydrazine/kg body wt. Formation of these bases in hamster liver DNA appeared similar to that reported earlier for rats and mice treated with necrogenic doses of hydrazine; however, persistence of O6-methylguanine in liver DNA following hydrazine administration was longer in hamster than in rat liver DNA. Administration of hydrazine sulfate in the drinking water of hamsters over a 9-week period resulted in accumulation of both 7-methylguanine and O6-methylguanine in liver DNA to the extent that about 2 out of every 10,000 guanine bases were methylated at each position on the base. Diethyl maleate pretreatment of hamsters depleted liver stores of glutathione and blocked DNA methylation in hydrazine-treated animals; however, buthionine sulfoximine, which also depleted glutathione stores, had no effect on the DNA methylation response to hydrazine poisoning in Sprague-Dawley rats. Hydrazine administration to hamsters and Swiss Webster mice resulted in more 7-methylguanine and O6-methylguanine in liver DNA than did administration of monomethylhydrazine, a proposed intermediate in the hydrazine-DNA methylation response. Even at the highest feasible dose of monomethylhydrazine to hamsters, no methylguanines could be detected, while these aberrant bases were readily quantifiable following hydrazine administration; thus, no evidence was obtained to support the proposal that monomethylhydrazine is an important intermediate in the methylation of DNA guanine in hydrazine-treated animals. PMID:6623473

  18. The effects of DNA double-strand breaks on mouse oocyte meiotic maturation

    PubMed Central

    Ma, Jun-Yu; Ou Yang, Ying-Chun; Wang, Zhong-Wei; Wang, Zhen-Bo; Jiang, Zong-Zhe; Luo, Shi-Ming; Hou, Yi; Liu, Zhonghua; Schatten, Heide; Sun, Qing-Yuan

    2013-01-01

    Both endogenous and exogenous factors can induce DNA double-strand breaks (DSBs) in oocytes, which is a potential risk for human-assisted reproductive technology as well as animal nuclear transfer. Here we used bleomycin (BLM) and laser micro-beam dissection (LMD) to induce DNA DSBs in germinal vesicle (GV) stage oocytes and compared the germinal vesicle breakdown (GVBD) rates and first polar body extrusion (PBE) rates between DNA DSB oocytes and untreated oocytes. Employing live cell imaging and immunofluorescence labeling, we observed the dynamics of DNA fragments during oocyte maturation. We also determined the cyclin B1 expression pattern in oocytes to analyze spindle assembly checkpoint (SAC) activity in DNA DSB oocytes. We used parthenogenetic activation to determine if the DNA DSB oocytes could be activated. As a result, we found that the BLM- or LMD-induced DSB oocytes showed lower GVBD rates and took a longer time to undergo GVBD compared with untreated oocytes. PBE was also delayed in DSB oocytes, but once GVBD had occurred, PBE was not affected, even in oocytes with severe DSBs. Compared with control oocytes, the DSB oocytes showed higher SAC activity, as indicated by less Ccnb1-GFP degradation during metaphase I to anaphase I transition. Parthenogenetic activation could activate the metaphase to interphase transition in the DNA DSB mature oocytes, but many oocytes contained multiple pronuclei or numerous micronuclei. These data suggest that DNA damage inhibits or delays the G2/M transition, but once GVBD occurs, DNA-damaged oocytes can complete chromosome separation and polar body extrusion even under a higher SAC activity, causing the formation of numerous micronuclei in early embryos. PMID:23518501

  19. A Novel Role for DNA Methyltransferase 1 in Regulating Oocyte Cytoplasmic Maturation in Pigs

    PubMed Central

    Huan, Yanjun; Xie, Bingteng; Liu, Shichao; Kong, Qingran; Liu, Zhonghua

    2015-01-01

    Maternal factors are required for oocyte maturation and embryo development. To better understand the role of DNA methyltransferase 1 (Dnmt1) in oocyte maturation and embryo development, small interfering RNA (siRNA) was conducted in porcine oocytes. In this study, our results showed that Dnmt1 localized in oocyte cytoplasm and its expression displayed no obvious change during oocyte maturation. When siRNAs targeting Dnmt1 were injected into germinal vesicle (GV) stage oocytes, Dnmt1 transcripts significantly decreased in matured oocytes (P<0.05). After Dnmt1 knockdown in GV stage oocytes, the significant reduction of glutathione content, mitochondrial DNA copy number, glucose-6-phosphate dehydrogenase activity and expression profiles of maternal factors and the severely disrupted distribution of cortical granules were observed in MII stage oocytes (P<0.05), leading to the impaired oocyte cytoplasm. Further study displayed that Dnmt1 knockdown in GV stage oocytes significantly reduced the development of early embryos generated through parthenogenetic activation, in vitro fertilization and somatic cell nuclear transfer (P<0.05). In conclusion, Dnmt1 was indispensable for oocyte cytoplasmic maturation, providing a novel role for Dnmt1 in the regulation of oocyte maturation. PMID:26009894

  20. mRNA from NCB-20 cells encodes the N-methyl-D-aspartate/phencyclidine receptor: a Xenopus oocyte expression study.

    PubMed Central

    Lerma, J; Kushner, L; Spray, D C; Bennett, M V; Zukin, R S

    1989-01-01

    The mouse neuroblastoma--Chinese hamster brain hybrid cell line NCB-20 is the only clonal cell line in which binding studies indicate the presence of phencyclidine (PCP) receptors. We report here that Xenopus oocytes injected with NCB-20 cell poly(A)+ RNA express N-methyl-D-aspartate (NMDA)-activated channels and that these channels include the PCP receptor site. In injected oocytes, NMDA application evoked a partially desensitizing inward current that was potentiated by glycine, blocked by the competitive antagonist D-2-amino-5-phosphonovaleric acid, blocked by Mg2+ and by Zn2+, and blocked in a use-dependent manner by the PCP receptor ligands PCP and MK-801. There was little or no response to kainate or quisqualate (agonists of the other excitatory amino acid receptors), to gamma-aminobutyric acid (an inhibitory transmitter), or to glycine (an inhibitory transmitter as well as an allosteric potentiator of NMDA channels). Thus, NMDA/PCP receptors expressed from NCB-20 cell mRNA exhibit properties similar to those of the neuronal receptors. The absence of expression of other excitatory amino acid receptors in this system makes it particularly useful for study of NMDA-evoked responses without interference from responses mediated by other receptors. Moreover, NCB-20 mRNA may be an appropriate starting material for cloning the cDNA(s) encoding the NMDA/PCP-receptor complex. PMID:2537982

  1. Intracellular mechanisms regulating apoB-containing lipoprotein assembly and secretion in primary hamster hepatocytes

    Microsoft Academic Search

    Changiz Taghibiglou; Debbie Rudy; Stephen C. Van Iderstine; Andrea Aiton; Dora Cavallo; Raphael Cheung; Khosrow Adeli

    We studied the biogenesis of apolipoprotein B (apoB) in primary hepatocytes isolated from hamster liver, an animal model with striking resemblance to humans in lipoprotein metabolism. Hamster hepatocytes were found to assemble and secrete apoB-containing lipoproteins at a density of VLDL. Intracellular mechanisms of apoB biogen- esis were investigated in both intact and permeabilized hamster hepatocytes. Translocational status of hamster

  2. Naturally occurring mastitis disrupts developmental competence of bovine oocytes.

    PubMed

    Roth, Z; Dvir, A; Kalo, D; Lavon, Y; Krifucks, O; Wolfenson, D; Leitner, G

    2013-10-01

    We examined the effects of naturally occurring mastitis on bovine oocyte developmental competence in vitro. Specifically, we investigated the effects of intramammary infection on the ovarian pool of oocytes (i.e., follicle-enclosed oocytes) and their ability to undergo in vitro maturation, fertilization, and further development to the blastocyst stage. Culled Holstein cows (n=50) from 9 commercial dairy farms in Israel were allotted to 3 groups according to somatic cell count (SCC) records of the last 3 monthly milk tests as well as of quarter samples collected before slaughter: (1) low SCC (n=7), (2) medium SCC (n=16), or (3) high SCC (n=27). Means of SCC values differed among low-, medium-, and high-SCC groups: 148,000, 311,000 and 1,813,000 cell/mL milk, respectively. Milk yield and days in milk did not differ among the 3 groups. Bacterial isolates included coagulase-negative staphylococci, Escherichia coli, Streptococcus dysgalactiae, or no bacteria found. Ovaries were collected at the abattoir and brought to the laboratory. Cumulus oocyte complexes were recovered separately from each cow and subjected individually to in vitro maturation and fertilization, followed by 8d in culture. The number of aspirated oocytes did not differ among groups, with a range of 17 to 21 oocytes per cow. The proportion of oocytes that cleaved into 2- to 4-cell-stage embryos (86.1 ± 3.4%) did not differ among groups. In contrast, mean percentages of embryos developed to the blastocyst stage on d 7 and 8 after fertilization were less in both medium- and-high SCC groups than in the low-SCC group (5.6 ± 2.3 and 4.1 ± 1.8 vs. 18.1 ± 4.6%, respectively). Additional analysis indicated that cleavage and blastocyst-formation rates did not differ among the bacterial types in the low-, medium-, and high-SCC groups. These are the first results to demonstrate that naturally occurring mastitis disrupts the developmental competence of the ovarian pool of oocytes, (i.e., oocytes at the germinal vesicle stage). The disruption was associated with elevation of SCC rather than bacterial type. The results may provide a partial explanation for the low fertility of cows that have contracted mastitic pathogens before insemination. PMID:23957998

  3. Signalling pathways involved in oocyte growth, acquisition of competence and activation.

    PubMed

    Nunes, Cláudia; Silva, Joana Vieira; Silva, Vladimiro; Torgal, Isabel; Fardilha, Margarida

    2015-06-01

    The oocyte's primary function is to be fertilised by a spermatozoon in order to create a viable embryo. Oocyte growth and development are initiated during embryogenesis and occur in parallel to follicular development. Factors produced by the oocyte bind to receptors on follicular cells, ensuring follicular development. Oocytes begin meiosis during foetal development and are arrested in prophase I by elevated levels of cyclic adenosine monophosphate (cAMP). Activation of mitogen-activated protein kinases triggers degradation of cAMP, allowing oocyte maturation to proceed. The production of progesterone and prostaglandins during the ovulation process ultimately activates proteases, whose action helps to release the oocyte into the Fallopian tube. Oocyte activation depends on fertilisation and is induced by changes in intracellular calcium levels. Dysregulation of these pathways is involved in the pathogenesis of several diseases including the syndrome of oocyte maturation failure. PMID:25738216

  4. Widespread Changes in the Posttranscriptional Landscape at the Drosophila Oocyte-to-Embryo Transition

    E-print Network

    Kronja, Iva

    The oocyte-to-embryo transition marks the onset of development. The initial phase of this profound change from the differentiated oocyte to the totipotent embryo occurs in the absence of both transcription and mRNA ...

  5. High-throughput optofluidic system for the laser microsurgery of oocytes

    PubMed Central

    Chandsawangbhuwana, Charlie; Shi, Linda Z.; Zhu, Qingyuan; Alliegro, Mark C.; Berns, Michael W.

    2012-01-01

    Abstract. This study combines microfluidics with optical microablation in a microscopy system that allows for high-throughput manipulation of oocytes, automated media exchange, and long-term oocyte observation. The microfluidic component of the system transports oocytes from an inlet port into multiple flow channels. Within each channel, oocytes are confined against a microfluidic barrier using a steady fluid flow provided by an external computer-controlled syringe pump. This allows for easy media replacement without disturbing the oocyte location. The microfluidic and optical-laser microbeam ablation capabilities of the system were validated using surf clam (Spisula solidissima) oocytes that were immobilized in order to permit ablation of the 5 ?m diameter nucleolinus within the oocyte nucleolus. Oocytes were the followed and assayed for polar body ejection. PMID:22352645

  6. Pineal melatonin synthesis in Syrian hamsters: A summary

    NASA Astrophysics Data System (ADS)

    Rollag, M. D.

    1982-12-01

    During the past decade there has been ample documentation of the proposition that the pineal gland mediates photoperiodic influences upon reproductive behavior of hamsters. It is commonly hypothesized that the pineal gland expresses its activity by transformation of photoperiodic information into an hormonal output, that hormone being melatonin. If this hypothesis is correct, there must be some essential diffrence in melatonin's output when hamsters are exposed to different photoperiodic environments. The experiments summarized in this communication analyze pineal melatonin contents in Syrian hamsters maintained in a variety of photoperiodic conditions during different physiological states. The results demonstrate that adult hamsters have a daily surge in pineal melatonin content throughout their lifetime when exposed to simulated annual photoperiodic cycles. There is some fluctuation in the amount of pineal melatonin produced during different physiological states and photoperiodic environments, but these fluctuations seem small when compared to those normally found for other regulatory hormones. When hamsters are exposed to different photoperiodic regimens, the daily melatonin surge maintains a relatively constant phase relationship with respect to the onset of daily activity. There is a concomitant change in its phase relationship with respect to light-dark transitions.

  7. Saprophytic and cycloheximide resistant fungi isolated from golden hamster.

    PubMed

    Bagy, M M; el-Shanawany, A A; Abdel-Mallek, A Y

    1998-01-01

    Healthy hair samples from golden hamsters were examined for the presence of dermatophytes and non-dermatophytes using baiting technique and direct inoculation. Thirty-four species and 2 varieties attributed to 17 genera were recovered. Paecilomyces variotii (isolated from 84.4% of the examined hair) and Aspergillus niger (81.3%) were the more frequent isolates on Sabouraud's dextrose agar (SDA) without cycloheximide. Our results have clearly demonstrated that the hair of hamster was free from true dermatophytes. Using the dilution plate method many fungal species were isolated from cage material (7 genera and 10 species + 1 variety); from faeces (10 genera and 17 species); from standard chow (3 genera and 6 species) of hamster. P. variotii which was the most frequent fungus in the preceding 3 substrates was completely absent in the presence of cycloheximide in SDA. The present study has demonstrated for the first time the isolation of Trichophyton rubrum from hamster faeces. Also, several saprophytic and cycloheximide resistant fungi were isolated. In the air of hamster cage Cladosporium cladosporioides, Penicillium chrysogenum, Alternaria alternata and Scopulariopsis brevicaulis were the most dominant species on SDA with or without cycloheximide. Using the agar diffusion method, Aloe sap, onion oil, garlic bulb extract and aqueous leaf extracts of Andropogon citratus, Euphorbia sp. and Ruta graveolens were tested for their antifungal activity on 10 fungal species. It was observed that onion oil exhibited a high inhibitory effect against most of the tested fungi. PMID:9768288

  8. Hamster and murine models of severe destructive Lyme arthritis.

    PubMed

    Munson, Erik; Nardelli, Dean T; Du Chateau, Brian K; Callister, Steven M; Schell, Ronald F

    2012-01-01

    Arthritis is a frequent complication of infection in humans with Borrelia burgdorferi. Weeks to months following the onset of Lyme borreliosis, a histopathological reaction characteristic of synovitis including bone, joint, muscle, or tendon pain may occur. A subpopulation of patients may progress to a chronic, debilitating arthritis months to years after infection which has been classified as severe destructive Lyme arthritis. This arthritis involves focal bone erosion and destruction of articular cartilage. Hamsters and mice are animal models that have been utilized to study articular manifestations of Lyme borreliosis. Infection of immunocompetent LSH hamsters or C3H mice results in a transient synovitis. However, severe destructive Lyme arthritis can be induced by infecting irradiated hamsters or mice and immunocompetent Borrelia-vaccinated hamsters, mice, and interferon-gamma- (IFN-?-) deficient mice with viable B. burgdorferi. The hamster model of severe destructive Lyme arthritis facilitates easy assessment of Lyme borreliosis vaccine preparations for deleterious effects while murine models of severe destructive Lyme arthritis allow for investigation of mechanisms of immunopathology. PMID:22461836

  9. The hamster flank organ model: Is it relevant to man

    SciTech Connect

    Franz, T.J.; Lehman, P.A.; Pochi, P.; Odland, G.F.; Olerud, J. (Univ. of Washington, Seattle (USA))

    1989-10-01

    The critical role that androgens play in the etiology of acne has led to a search for topically active antiandrogens and the frequent use of the flank organ of the golden Syrian hamster as an animal model. 17-alpha-propyltestosterone (17-PT) has been identified as having potent antiandrogenic activity in the hamster model, and this report describes its clinical evaluation. Two double-blind placebo controlled studies comparing 4% 17-PT in 80% alcohol versus vehicle alone were conducted. One study examined 17-PT sebosuppressive activity in 20 subjects. The second study examined its efficacy in 44 subjects having mild to moderate acne. A third study measured in vitro percutaneous absorption of 17-PT through hamster flank and monkey skin, and human face skin in-vivo, using radioactive drug. 17-PT was found to be ineffective in reducing either the sebum excretion rate or the number of inflammatory acne lesions. Failure of 17-PT to show clinical activity was not a result of poor percutaneous absorption. Total absorption in man was 7.7% of the dose and only 1.0% in the hamster. The sebaceous gland of hamster flank organ is apparently more sensitive to antiandrogens than the human sebaceous gland.

  10. Water penetration study

    NASA Technical Reports Server (NTRS)

    Lockwood, H. E.

    1973-01-01

    Nine film-filter combinations have been tested for effectiveness in recording water subsurface detail when exposed from an aerial platform over a typical water body. An experimental 2-layer positive color film, a 2-layer (minus blue layer) film, a normal 3-layer color film, a panchromatic black-and-white film, and an infrared film with selected filters were tested. Results have been tabulated to show the relative capability of each film-filter combination for: (1) image contrast in shallow water (0 to 5 feet); (2) image contrast at medium depth (5 to 10 feet); (3) image contrast in deep water (10 feet plus); (4) water penetration; maximum depth where detail was discriminated; (5) image color (the spectral range of the image); (6) vegetation visible above a water background; (7) specular reflections visible from the water surface; and (8) visual compatibility; ease of discriminating image detail. Recommendations for future recording over water bodies are included.

  11. Universal penetration test apparatus with fluid penetration sensor

    DOEpatents

    Johnson, P.W.; Stampfer, J.F.; Bradley, O.D.

    1999-02-02

    A universal penetration test apparatus is described for measuring resistance of a material to a challenge fluid. The apparatus includes a pad saturated with the challenge fluid. The apparatus includes a compression assembly for compressing the material between the pad and a compression member. The apparatus also includes a sensor mechanism for automatically detecting when the challenge fluid penetrates the material. 23 figs.

  12. Universal penetration test apparatus with fluid penetration sensor

    DOEpatents

    Johnson, Phillip W. (Rochester, MN); Stampfer, Joseph F. (Santa Fe, NM); Bradley, Orvil D. (Santa Fe, NM)

    1999-01-01

    A universal penetration test apparatus for measuring resistance of a material to a challenge fluid. The apparatus includes a pad saturated with the challenge fluid. The apparatus includes a compression assembly for compressing the material between the pad and a compression member. The apparatus also includes a sensor mechanism for automatically detecting when the challenge fluid penetrates the material.

  13. Effects of Putative Satiety Peptides on Feeding and Drinking Behavior in Golden Hamsters (Mesocricetus auratus )

    Microsoft Academic Search

    Mario O. Miceli; Charles W. Malsbury

    1985-01-01

    A series of experiments was conducted to characterize the effects of putative satiety peptides on feeding in the Syrian hamster, a species known to have physiological feeding controls different from those of other animals. Peripheral injections of cholecystokinin octapeptide (CCK-8) reduced feeding in hamsters in a dose-related fashion. CCK-8 was equally effective in reducing food intake in female hamsters tested

  14. How does the running wheel affect the behaviour and reproduction of golden hamsters kept as pets?

    Microsoft Academic Search

    Sabine G. Gebhardt-Henrich; Evelyne M. Vonlanthen; Andreas Steiger

    2005-01-01

    Although there are many studies on the running wheel in laboratory animals, it is not clear if a running wheel should be provided for golden hamsters kept as pets. Unlike laboratory animals, golden hamsters kept as pets usually have larger cages, more varied food, and are kept singly. In this study, 10 sister-pairs of golden hamsters were kept singly in

  15. A NEURAL NETWORK UNDERLYING INDIVIDUAL DIFFERENCES IN EMOTION AND AGGRESSION IN MALE GOLDEN HAMSTERS

    E-print Network

    Delville, Yvon

    HAMSTERS J. T. DAVID, M. C. CERVANTES, K. A. TROSKY, J. A. SALINAS AND Y. DELVILLE* Psychology Department a common neural network. Male golden hamsters were first screened for offensive aggression. Then. Similar protocols have been used to test behaviors associated with frustration. At first, all hamsters

  16. Leptin Effects on Immune Function and Energy Balance Are Photoperiod Dependent in Siberian Hamsters

    E-print Network

    Demas, Greg

    Leptin Effects on Immune Function and Energy Balance Are Photoperiod Dependent in Siberian Hamsters- sters (Phodopus sungorus) housed in long or short days for a total of 12 weeks. Short-day hamsters days. In Exp 2, when the leptin-induced increase in food intake in short-day hamsters was prevented

  17. Response to exogenous kisspeptin varies according to sex and reproductive condition in Siberian hamsters (Phodopus sungorus)

    E-print Network

    Demas, Greg

    hamsters (Phodopus sungorus) Timothy J. Greives, Kimberly L. Long, Christine M. Bergeon Burns, Gregory E Siberian hamsters held on reproductively inhibitory or stimulatory photoperiods. In Experiment 2, we asked in this response, with males showing greater LH responses to kisspeptin than females. Hamsters responded

  18. Synchrotron FT-IR Analysis of Collagen Localization in Normal, Cardiomyopathic and Losartan-treated Hamsters

    E-print Network

    -treated Hamsters K.M. Gough, I. Dixon, P. Bromberg, D. Zielinski Department of Chemistry, University of Manitoba scale). Figure 1. Photomicrograph of stained cardiomyopathic heart tissue from Syrian hamsters. Blue and localization of collagen in model animals: the UM-X7.1 strain of Syrian hamsters. In cases where a collagen

  19. Photoperiod Affects Neuronal Nitric Oxide Synthase and Aggressive Behaviour in Male Siberian Hamsters (Phodopus

    E-print Network

    Demas, Greg

    Hamsters (Phodopus sungorus) J. C. Wen,*a A. K. Hotchkiss,* G. E. Demas and R. J. Nelson* *Departments University, Bloomington, IN, USA. Key words: photoperiod, Siberian hamster, seasonal, aggression, nitric including photoperiod (day length). Male Siberian hamsters (Phodopus sungorus) housed in short photoperiod

  20. Refractoriness to melatonin occurs independently at multiple brain sites in Siberian hamsters

    E-print Network

    Zucker, Irving

    Refractoriness to melatonin occurs independently at multiple brain sites in Siberian hamsters David on these brain nuclei, induced testicular regression within 6 wk in male Siberian hamsters; 12 wk later Mel implants no longer suppressed reproduction and gonadal recrudescence ensued. Hamsters that were then given

  1. POUVOIR PATHOGNE EXPRIMENTAL DES MYCOBACTRIES DITES ATYPIQUES CHEZ LA SOURIS, LE HAMSTER ET LE MRION

    E-print Network

    Paris-Sud XI, Université de

    POUVOIR PATHOGÈNE EXPÉRIMENTAL DES MYCOBACTÉRIES DITES «ATYPIQUES» CHEZ LA SOURIS, LE HAMSTER ET LE, HAMSTER AND MERION. ― Three animal species were used for the experimental pathogenicity of fourteen of healthy pigs in the surrounding area of Montevideo. White mice, hamsters and merions were inoculated

  2. Behavioural and Neuroendocrine Adaptations to Repeated Stress during Puberty in Male Golden Hamsters

    E-print Network

    Delville, Yvon

    Hamsters J. C. Wommack,* A. Salinas,* R. H. Melloni Jr, and Y. Delville* *Psychology Department, the consequences of stress are often severe and long lasting. Repeated subjugation in adult male golden hamsters-pubertal changes in stress hormones may explain why juvenile hamsters are more resilient to social stress than

  3. Photoperiod-dependent effects of neuronal nitric oxide synthase inhibition on aggression in Siberian hamsters

    E-print Network

    Demas, Greg

    in Siberian hamsters Tracy A. Bedrosian a, , Laura K. Fonken a , Gregory E. Demas b , Randy J. Nelson and aggression. Seasonally-breeding Siberian hamsters, however, are paradoxically more aggressive in short, is associated with increased aggression in male short-day hamsters. In the present study, we hypothesized

  4. Replacement of hamsters with physiochemical analytical methods for Leptospira vaccine batch

    E-print Network

    Chittka, Lars

    1 Replacement of hamsters with physiochemical analytical methods for Leptospira vaccine batch and Veterinary Laboratories Agency (AHVLA). Histological processing and analysis of hamster tissue was performed serovar Canicola vaccines requires the use of a large number of hamsters and has severe effects; whilst

  5. Neuropeptide Y Activates Protein Kinase C in Hamster Suprachiasmatic Nuclei Brain Slices

    E-print Network

    Harrington, Mary

    Neuropeptide Y Activates Protein Kinase C in Hamster Suprachiasmatic Nuclei Brain Slices Kathryn M in the SCN of a variety of animal species including the hamster (Biello et al., 1997; Van der Zee & Bult to test the hypothesis that neuropeptide Y should increase PKC activity in the hamster SCN. Material

  6. Perinatal Influences of Melatonin on Testicular Development and Photoperiodic Memory in Siberian Hamsters

    E-print Network

    Zucker, Irving

    Hamsters C. R. Tuthill,* D. A. Freeman, M. P. Butler, Tori Chinn,* J. H. Park* and I. Zucker* Departments, University of Memphis, Memphis, TN, USA. Key words: melatonin, hamster, photoperiodism, development, testes) was substantially reduced in Siberian hamsters gestated by pinealectomised compared to pineal-intact females

  7. Pubertal growth of the medial amygdala delayed by short photoperiods in the Siberian hamster, Phodopus sungorus

    E-print Network

    Breedlove, Marc

    Pubertal growth of the medial amygdala delayed by short photoperiods in the Siberian hamster nucleus of the amygdala (MeA) by comparing Siberian hamsters (Phodopus sungorus) that had been raised from birth in either long day (LD; 16:8 h light:dark) or short day (SD; 8:16) photoperiods. Hamsters were

  8. Differential Cytokine Gene Expression According to Outcome in a Hamster Model of Leptospirosis

    E-print Network

    Paris-Sud XI, Université de

    Differential Cytokine Gene Expression According to Outcome in a Hamster Model of Leptospirosis Fre studied in a hamster model. Methodology/Principal Findings: Using an LD50 model of leptospirosis in hamsters, we first determined that 3 days post- infection was a time-point that allowed studying

  9. Acute and Chronic Social Defeat Suppresses Humoral Immunity of Male Syrian Hamsters

    E-print Network

    Demas, Greg

    Acute and Chronic Social Defeat Suppresses Humoral Immunity of Male Syrian Hamsters (Mesocricetus examined the role of a stressor, social defeat, on humoral immune function of Syrian hamsters (Me- vated in both acutely and chronically defeated hamsters compared with control animals. In contrast

  10. Development and initiation of sperm motility in the hamster Marie-Louise KANN, Catherine SERRES

    E-print Network

    Paris-Sud XI, Université de

    Development and initiation of sperm motility in the hamster epididymis Marie-Louise KANN, Catherine Bicêtre, 78 rue du Général Leclerc 94270 Kremlin-Bicêtre, France. Summary. Hamster spermatozoa were of the head movements. It is shown that during epididymal transit of hamster spermatozoa, the induction

  11. Analysis of superovulation in the hamster : 1962-1978 G. S. GREENWALD

    E-print Network

    Paris-Sud XI, Université de

    Analysis of superovulation in the hamster : 1962-1978 G. S. GREENWALD Department of Physiology in the cyclic hamster by single injections of PMSG. Four principal approaches have been used : 1) ovulation rate the hamster for studies of follicular growth and atresia. Introduction. For the past 16 yearsI have been

  12. CELL-MEDIATED CYTOTOXICITY AGAINST HAMSTER CELLS TRANSFORMED BY AVIAN SARCOMA VIRUSES.

    E-print Network

    Boyer, Edmond

    CELL-MEDIATED CYTOTOXICITY AGAINST HAMSTER CELLS TRANSFORMED BY AVIAN SARCOMA VIRUSES. 1 A MEDIATION CELLULAIRE ENVERS DES CELLULES DE HAMSTER TRANS- FORMEES PAR DES VIRUS DE SARCOMES AVIAIRES. 1. Description de la réaction. - La présence de nouveaux antigènes apparus à la surface de cellules de hamster

  13. CELL-MEDIATED CYTOTOXICITY AGAINST HAMSTER CELLS TRANSFORMED BY AVIAN SARCOMA VIRUSES

    E-print Network

    Paris-Sud XI, Université de

    CELL-MEDIATED CYTOTOXICITY AGAINST HAMSTER CELLS TRANSFORMED BY AVIAN SARCOMA VIRUSES 2 CYTOTOXICITE A MEDIATION CELLULAIRE ENVERS DES CELLULES DE HAMSTER TRANS- FORMEES PAR DES VIRUS DE SARCOMES apparus à la surface de différents clones de cellules de hamster transformées par des virus de sarcomes

  14. Gonadal hormones modulate the display of submissive behavior in socially defeated female Syrian hamsters

    E-print Network

    Demas, Greg

    hamsters Alicia N. Faruzzia , Matia B. Solomona , Gregory E. Demasb , Kim L. Huhmana,T a Department There are striking differences in the behavioral response to social defeat between male and female Syrian hamsters hamsters were ovariectomized and implanted with Silastic capsules containing estradiol (E2), testosterone

  15. Behavioral and Neurobiological Consequences of Social Subjugation during Puberty in Golden Hamsters

    E-print Network

    Delville, Yvon

    Behavioral and Neurobiological Consequences of Social Subjugation during Puberty in Golden Hamsters Department, University of Massachusetts Medical Center, Worcester, Massachusetts 01655 In golden hamsters subjugation) during puberty. Male golden hamsters were weaned at postna- tal day 25 (P25), exposed daily

  16. Resveratrol improves the quality of pig oocytes derived from early antral follicles through sirtuin 1 activation.

    PubMed

    Itami, N; Shirasuna, K; Kuwayama, T; Iwata, H

    2015-05-01

    During oocyte growth, the number of mitochondria drastically increases and mitochondrial function profoundly affects the oocyte competence. Resveratrol is a well-known activator of sirtuin 1 (SIRT1), which has a role in cellular energy homeostasis and mitochondrial biogenesis. The main aim of the present study was to examine the effect of supplementation of culture media with resveratrol on oocyte development and mitochondrial number and functions. Lipid contents and developmental ability of the oocytes grown in vitro were also examined. Oocyte-granulosa cell complexes were collected from early antral follicles of gilt ovaries and were cultured in medium containing 0 or 2 ?M resveratrol for 14 days. Immunostaining revealed that resveratrol enhanced SIRT1 expression in oocytes. Antrum formation during the culture period and survivability of the granulosa cells surrounding the developed oocytes did not differ between the two concentrations of resveratrol. In addition, the ability of oocytes to complete meiotic maturation did not differ between the two concentrations of resveratrol, whereas the ability of oocytes to develop to the blastocyst stage was improved significantly by resveratrol (7.4% vs. 1.6%; P < 0.05). Resveratrol upregulated the ATP content in oocytes grown in vitro, and the addition of 2 ?M of the SIRT1 inhibitor 6-Chloro-2,3,4,9-tetrahydro-1H-carbazole-1-carboxamide (EX527) diminished this effect although EX527 alone had no effect on ATP content. The mitochondrial DNA copy number in oocytes determined by quantitative real-time polymerase chain reaction increased during in vitro oocyte development, but resveratrol did not affect the kinetics of the mitochondrial DNA copy number. We found that resveratrol also increased the expression level of phospho-5'-adenosine monophosphate-activated protein kinase in oocytes but decreased the lipid content in oocytes grown in vitro. These results suggest that resveratrol increased the ATP content in oocytes via energy homeostasis and improved the developmental ability of oocytes grown in vitro. PMID:25724287

  17. Full-grown oocytes from Xenopus laevis resume growth when placed in culture

    Microsoft Academic Search

    R. A. Wallace; Z. Misulovin; L. D. Etkin

    1981-01-01

    When most full-grown, follicle cell-invested oocytes from Xenopus laevis are placed in an appropriate culture medium, they resume growth and remain physiologically healthy for at least 2 to 3 weeks. Rates of growth by full-grown oocytes in vitro generally approximate and can even exceed the most rapid growth rate achieved by vitellogenic oocytes in vivo. Resumption of oocyte growth can

  18. The origin of yolk in the oocytes of Nereis virens (Annelida, Polychaeta)

    Microsoft Academic Search

    Albrecht Fischer; André Dhainaut

    1985-01-01

    Three different types of evidence are reported concerning the origin of yolk protein in the oocyte of the annelid Nereis virens. The fine structure of the oocyte and its different types of storage organelles are described; only few pinocytotic vesicles are found. Electron-microscopic autoradiography of oocytes incubated with 3H-leucine showed that the oocytes synthesize protein which, in part, becomes localized

  19. [Fertilizing capacity of the ejaculate of nutria (Myocastor coypus) after the removal of the seminal vesicles as evaluated by the penetration test and natural mating].

    PubMed

    Jakubicka, I; Barta, M; Babusík, P

    1989-07-01

    The fertility of male coypu sperm following seminal vesicle extirpation was investigated using the penetration test into the egg of Syrian golden hamster (Mesocricetus auratus). Ejaculates were obtained from five males by means of electro-ejaculation under halothane narcosis. The results of the zona-free hamster eggs (ZFHE) penetration test showed that the ejaculates of all the surgically treated coypu males were fertile and that ZFHE value fluctuated from 54 to 76.6%. The results obtained in experiments with natural mating revealed that the extirpation of male coypu seminal vesicles did not affect their fertility. In total 47 foetuses were found post mortem in ten coypu females covered by surgically treated males, which on average represented 4.7 foetuses per female. PMID:2678717

  20. Expression of TGF? superfamily components and other markers of oocyte quality in oocytes selected by brilliant cresyl blue staining: Relevance to early embryonic development

    PubMed Central

    Ashry, Mohamed; Lee, KyungBon; Mondal, Mohan; Datta, Tirtha K.; Folger, Joseph K.; Rajput, Sandeep K.; Zhang, Kun; Hemeida, Nabil A.; Smith, George W.

    2015-01-01

    Brilliant cresyl blue (BCB) is a super vital stain that has been used to select competent oocytes in different species. The objectives of present studies were to determine mRNA abundance for select TGF? superfamily components, SMAD2/3 and SMAD1/5 phosphorylation levels and transcript abundance for other oocyte (JY1) and cumulus cell (CTSB, CTSK, CTSS and CTSZ) markers of oocyte quality in bovine oocytes and or adjacent cumulus cells classified based on developmental potential using BCB staining. The ability of exogenous FST, JY1, or cathepsin inhibitor treatment to enhance development of embryos derived from poor quality oocytes selected based on BCB staining was also determined. Cumulus oocyte complexes (COCs) from abattoir derived ovaries were subjected to BCB staining and GV stage oocytes and cumulus cells harvested from control, BCB+ and BCB- (poor oocyte quality) groups for real time PCR or Western blot analysis. Remaining COCs underwent in vitro maturation, in vitro fertilization and embryo culture in presence or absence of above described treatments. Levels of FST, JY1, BMP15 and SMAD1, 2, 3 and 5 transcripts were higher in BCB+ oocytes whereas abundance of CTSB, CTSK, CTSS and CTSZ mRNAs was higher in cumulus cells surrounding poor quality BCB- oocytes. Western blot analysis revealed SMAD1/5 and SMAD2/3 phosphorylation were higher in BCB+ than BCB? oocytes. Embryo culture studies demonstrated that follistatin and cathepsin inhibitor treatment but not JY-1 treatment can promote developmental competence of BCB- oocytes. Results provide further understanding of molecular indices of oocyte competence. PMID:25704641

  1. Ethical issues in paying for long-distance travel and accommodation expenses of oocyte donors

    Microsoft Academic Search

    Boon Chin Heng

    2005-01-01

    In many countries where the sale and purchase of donor oocytes is banned, a legal loophole often exploited is the use of free air tickets and hotel stay to entice prospective oocyte donors, in lieu of monetary payment. Such a means of procuring much-needed donor oocytes is ethically unsound. There is a lack of transparency and the personal motivation of

  2. Reproduced with permission from Reproductive Healthcare Ltd. Identifying new human oocyte marker genes: a

    E-print Network

    Paris-Sud XI, Université de

    Reproduced with permission from Reproductive Healthcare Ltd. Identifying new human oocyte marker of these genes as well as other related genes in human oocytes and cumulus cells. In this study, we identified) demonstrated that, in vitro, the culture of human oocytes with attached cumulus cells may improve

  3. Changes in the 3-dimensional distribution of mitochondria during meiotic divisions of mouse oocytes

    Microsoft Academic Search

    C. J. Li; B. Q. Fan

    1997-01-01

    Mitochondrial reorganization during meiotic maturation and parthenogenetic activation was studied in mouse oocytes using a laser scanning confocal microscope and a transmission electron microscope. Mitochondria were mainly distributed perinuclearly in the germinal vesicle (GV) stage oocytes and were dispersed throughout ooplasm after germinal vesicle breakdown (GVBD), except for a slightly higher occurrence in one hemisphere of oocytes, from which the

  4. Oocyte yield and dysmorphisms as indicators of biological efficiency in intracytoplasmic sperm injection cycles.

    PubMed

    Figueira, Rita de Cássia Savio; Braga, Daniela Paes Almeida Ferreira; Semião-Francisco, Luciana; Iaconelli, Assumpto; Borges, Edson

    2011-03-01

    The aim of the study was to examine whether oocyte yield could be an indicator of morphological oocyte quality and biological competency in patients younger than 36 years undergoing controlled ovarian stimulation (COS). Three hundred and thirty-five intracytoplasmic sperm injection (ICSI) procedures were arbitrarily subdivided into five groups according to the number of retrieved oocytes. Patients' demographic characteristics and treatment success were compared among the groups. The influence of the morphological oocyte abnormalities on outcomes was also investigated. The proportion of oocytes that gave rise to viable embryos and high-quality embryos decreased significantly according to oocyte yield. Similarly, the number of foetal heartbeat per retrieved oocyte in fresh embryo transfer cycles was higher in patients with fewer oocytes collected. Finally, a negative correlation was observed between the occurrence of intracytoplasmic oocyte dysmorphisms and the number of foetal heartbeat per oocyte. High oocyte yield may be considered an indicator of low oocyte biological efficiency and intracytoplasmic dysmorphisms may contribute to this biological wastage suggesting that protocols of minimal or mild stimulation should be used. PMID:21158694

  5. Immunocytogenetic detection of normal and abnormal oocytes in human fetal ovarian tissue in culture

    Microsoft Academic Search

    G. M. Hartshorne; A. L. Barlow; T. J. Child; D. H. Barlow; M. A. Hulten

    1999-01-01

    This study aimed to: (i) determine whether oocytes are present in cultures of human fetal ovary; (ii) identify whether meiotic anomalies are evident; and (iii) assess whether preparation or culture conditions influence oocyte survival and meiotic progression. Ovaries were collected from fetuses after termination at 13-16 weeks. Oocyte assessment utilized antibodies specific for synaptonemal complex proteins (associated with chromosomes only

  6. In vitro maturation of sheep ovarian oocytes D. SZLLSI Vronique DESMEDT, Nicole CROZET, Corinne BRENDER

    E-print Network

    Paris-Sud XI, Université de

    In vitro maturation of sheep ovarian oocytes D. SZÖLLÖSI Véronique DESMEDT, Nicole CROZET, Corinne maturation in 98 % ovarian sheep oocytes isolated from follicles 2-6 mm in diameter. 45.7 % of these were maturation, examining the nucleus, the cytoplasm and cumulus (corona)-oocyte rela- tionship. 24 h

  7. Developmental ability of human oocytes with or without birefringent spindles imaged by Polscope before insemination

    Microsoft Academic Search

    W. H. Wang; L. Meng; R. J. Hackett; D. L. Keefe

    2001-01-01

    BACKGROUND: Birefringent spindles imaged with the Polscope can predict fertilization rates after intracytoplasmic sperm injection (ICSI). The present study examined the development of human oocytes with or without birefringent spindles, imaged with the Polscope before ICSI. METHODS: Oocytes were obtained from stimulated ovaries of consenting patients undergoing oocyte retrieval for ICSI. Spindles were imaged with the Polscope combined with a

  8. Cyclin B synthesis is required for sea urchin oocyte maturation Ekaterina Voronina,a

    E-print Network

    Wessel, Gary M.

    Cyclin B synthesis is required for sea urchin oocyte maturation Ekaterina Voronina,a William F Sea urchins are members of a limited group of animals in which meiotic maturation of oocytes for in vitro maturation of sea urchin oocytes, we analyzed the role of cyclin B, the regulatory component

  9. MOLECULAR REPRODUCTION AND DEVELOPMENT 60:553561 (2001) Apoptosis in Sea Urchin Oocytes, Eggs, and

    E-print Network

    Wessel, Gary M.

    2001-01-01

    MOLECULAR REPRODUCTION AND DEVELOPMENT 60:553±561 (2001) Apoptosis in Sea Urchin Oocytes, Eggs of apoptosis assays in sea urchin oocytes, eggs, and early embryos experimentally induced to apoptose: apoptosis; sea urchin; oocyte; egg; staurosporine INTRODUCTION Apoptosis, or programmed cell death, plays

  10. Effect of Season and Exposure to Heat Stress on Oocyte Competence in Holstein Cows1

    Microsoft Academic Search

    Y. M. Al-Katanani; F. F. Paula-Lopes; P. J. Hansen

    2002-01-01

    Two experiments were conducted to evaluate sea- sonal variation in oocyte competence in Holstein cows and to test whether oocyte quality in summer is af- fected by the magnitude of heat stress. In the first experiment, ovaries of Holstein cows were collected from a slaughterhouse and used to harvest oocytes over 1 yr (n = 18 replicates). After in vitro

  11. INTRODUCTION The end-point of mammalian oocyte development is in the pro-

    E-print Network

    Newcastle upon Tyne, University of

    fertile oocyte. The mouse oocyte grows from an initial diameter of 20 µm to 70 µm in size, during which be stimulated in vitro by releasing the oocyte from the follicle into a suitable culture medium (Pincus metaphase II where it arrests, awaiting fertilization. At fertilization the sperm triggers a series

  12. Can Vero cell co-culture improve in-vitro maturation of bovine oocytes?

    Microsoft Academic Search

    Fariba Moulavi; Sayyed Mortaza Hosseini; Saeid Kazemi Ashtiani; Abdolhossein Shahverdi; Mohammad Hossein Nasr-Esfahani

    2006-01-01

    This study was carried out to evaluate the effect of Vero cell co-culture on developmental competence of immature oocytes. Bovine cumulus–oocyte complexes (COC) were matured in presence or absence of Vero cells. Matured oocytes were inseminated and cultured for up to 9 days. Cleavage percentages were recorded on day 2 after insemination and embryos were evaluated on a daily basis.

  13. Effects of vitrification on nuclear maturation, ultrastructural changes and gene expression of canine oocytes

    Microsoft Academic Search

    Bongkoch Turathum; Kulnasan Saikhun; Parisatcha Sangsuwan; Yindee Kitiyanant

    2010-01-01

    BACKGROUND: Cryopreservation of oocytes, which is an interesting procedure to conserve female gametes, is an essential part of reproductive biotechnology. The objective of the present study was to investigate the effects of vitrification on nuclear maturation, ultrastructural changes and gene expression of canine oocytes. METHODS: Immature oocytes (germinal vesicles) isolated from ovaries of normal bitches (> 6 months of age)

  14. A new approach for the oocyte genotoxicity assay: adaptation of comet assay on mouse cumulus-oocyte complexes.

    PubMed

    Greco, F; Perrin, J; Auffan, M; Tassistro, V; Orsière, T; Courbiere, B

    2015-07-01

    Conventional genotoxicity tests are technically difficult to apply to oocytes, and results obtained on somatic cells cannot be extrapolated to gametes. We have previously described a comet assay (original-CA) on denuded mouse oocytes, but, in vivo, oocytes are not isolated from their surrounding follicular cells. Our objective was to develop a comet assay on cumulus-oocyte complexes (COC-CA) for a more physiological approach to study the genotoxicity of environmental factors on oocytes. For COC-CA, whole COC were exposed directly to exogenous agents after ovulation and removal from oviducts. Three conditions were studied: a negative control group, and two positive control groups, one of which was exposed to hydrogen peroxide (H2O2) and the other group was incubated with cerium dioxide nanoparticles (CeO2 NPs). With both tests, DNA damage was significant in the presence of both H2O2 and CeO2 NPs compared with the negative control. COC-CA offers an interesting tool for assaying the genotoxicity of environmental agents towards germinal cells. Furthermore, COC-CA is less time-consuming and simplifies the protocol of the original-CA, because COC-CA is easier to perform without the washing-out procedure. PMID:25552520

  15. Human Oocyte Vitrification: The permeability of metaphase II oocytes to water and ethylene glycol and the appliance toward vitrification

    PubMed Central

    Mullen, Steven F.; Li, Mei; Li, Yuan; Chen, Zi-Jiang; Critser, John K.

    2008-01-01

    Objectives To determine the permeability of human metaphase II oocytes to ethylene glycol and water in the presence of ethylene glycol, and to use this information to develop a method to vitrify human oocytes. Design An incomplete randomized block design was used for this study. Setting A University-affiliated assisted reproductive center. Patients Women undergoing assisted reproduction in the Center for Reproductive Medicine at Shandong University. Interventions Oocytes were exposed to 1.0 molar ethylene glycol in a single step, and photographed during subsequent volume excursions. Main outcome measures A 2-parameter model was employed to estimate the permeability to water and EG. Results Water permeability ranged from 0.15 to 1.17 µm/(min·atm), and ethylene glycol permeability ranged from 1.5 to 30 µm/min between 7 °C at 36 °C. The activation energies for water and ethylene glycol permeability were 14.42 Kcal/mol and 21.20 Kcal/mol, respectively. Conclusions Despite the lower permeability of human MII oocytes to ethylene glycol compared to previously published values for propylene glycol and dimethylsulfoxide, methods to add and remove human oocytes with a vitrifiable concentration of ethylene glycol can be designed which prevent excessive osmotic stress and minimize exposure to high concentrations of this compound. PMID:17681308

  16. Oocyte differentiation is genetically dissociable from meiosis in mice

    PubMed Central

    Dokshin, Gregoriy A.; Baltus, Andrew E.; Eppig, John J.; Page, David C.

    2013-01-01

    Oogenesis is the process by which ovarian germ cells undertake meiosis and differentiate to become eggs. In mice, Stra8 is required for the chromosomal events of meiosis to occur, but its role in differentiation remains unknown. Here we report Stra8-deficient ovarian germ cells that grow and differentiate into oocyte-like cells that synthesize zonae pellucidae, organize surrounding somatic cells into follicles, are ovulated in response to hormonal stimulation, undergo asymmetric cell division to produce a polar body, and cleave to form two-cell embryos upon fertilization. These events occur without premeiotic chromosomal replication, sister chromatid cohesion, synapsis, or recombination. Thus, oocyte growth and differentiation are genetically dissociable from the chromosomal events of meiosis. These findings open to study the independent contributions of meiosis and oocyte differentiation to the making of a functional egg. PMID:23770609

  17. Telescience testbed experiments of intracellular recordings in the Xenopus oocyte.

    PubMed

    Ando, H; Watanabe, S; Mori, S; Tanaka, M; Wada, Y; Suzuki, H; Takagi, S; Nagaoka, S; Matsumoto, K; Suzuki, T; Fukai, K; Kanazawa, Y; Hirakawa, K; Ogasawara, K; Tsumura, K; Ogawa, K; Shimura, R; Ohshima, M; Yamashita, M

    1994-01-01

    The feasibility of intracellular recordings under constraints for experimental conditions in outer space were tested at a telescience testbed of the National Space Development Agency of Japan. We attempted to study the dose-response relationship of adenosine-induced potential changes in the Xenopus oocyte. The testbed simulated the distance from a ground control room to oocytes in an orbital laboratory; signals were delayed and compressed from one "station" to other. A microelectrode was inserted into the oocyte using remote control on the manipulator and on the xyz-planes of the platform with stereoscopic pictures observed through a head mounted display. When the transfer rate of the visual signals was decreased from 1.5 Mbps to 128 Kbps, insertion of the electrode became almost impossible because of reduced picture quality. Once the electrode was inserted, however, dose-dependent adenosine responses could be observed with little trouble. PMID:12703519

  18. Live imaging of GFP-labeled proteins in Drosophila oocytes.

    PubMed

    Pokrywka, Nancy Jo

    2013-01-01

    The Drosophila oocyte has been established as a versatile system for investigating fundamental questions such as cytoskeletal function, cell organization, and organelle structure and function. The availability of various GFP-tagged proteins means that many cellular processes can be monitored in living cells over the course of minutes or hours, and using this technique, processes such as RNP transport, epithelial morphogenesis, and tissue remodeling have been described in great detail in Drosophila oocytes. The ability to perform video imaging combined with a rich repertoire of mutants allows an enormous variety of genes and processes to be examined in incredible detail. One such example is the process of ooplasmic streaming, which initiates at mid-oogenesis. This vigorous movement of cytoplasmic vesicles is microtubule and kinesin-dependent and provides a useful system for investigating cytoskeleton function at these stages. Here I present a protocol for time lapse imaging of living oocytes using virtually any confocal microscopy setup. PMID:23567977

  19. Ground-penetrating radar methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ground-penetrating radar geophysical methods are finding greater and greater use in agriculture. With the ground-penetrating radar (GPR) method, an electromagnetic radio energy (radar) pulse is directed into the subsurface, followed by measurement of the elapsed time taken by the radar signal as it ...

  20. Sidewall penetrator for oil wells

    NASA Technical Reports Server (NTRS)

    Collins, E. R., Jr.

    1981-01-01

    Penetrator bores horizontal holes in well casing to increase trapped oil drainage. Several penetrators operated by common drive are inserted into well at once. Shaft, made from spiraling cable, rotates and thrusts simultaneously through rigid curvilinear guide tube forcing bit through casing into strata. Device pierces more deeply than armor-piercing bullets and shaped explosive charges.

  1. The thalamic intergeniculate leaflet modulates photoperiod responsiveness in Siberian hamsters.

    PubMed

    Freeman, David A; Dhandapani, Krishnan M; Goldman, Bruce D

    2004-11-26

    Siberian hamsters are seasonal breeders that use changes in day length to synchronize their reproductive effort with those times of the year most favorable for successful reproduction. The ability of Siberian hamsters to measure and respond to changes in day length depends upon accurate photoentrainment of the circadian clock in the suprachiasmatic nucleus (SCN) of the hypothalamus. Two pathways have been characterized through which entraining stimuli reach the SCN: the retinohypothalamic tract (RHT), which transmits light information from the retinae, and the geniculohypothalamic tract (GHT) from the intergeniculate leaflet of the thalamus (IGL), which is involved in transmitting both photic and nonphotic cues. Ablating the IGL/GHT results in only modest alterations in entrainment to static day lengths and fails to interfere with seasonal responses induced by transfer from static long day to static short day lengths. Because several studies suggest that the IGL may be involved in tracking the time of dusk and dawn, we sought to determine whether an intact IGL is necessary for hamsters to respond to a simulated natural photoperiod (SNP) in which the time of dusk and dawn gradually changes in a pattern approximating the rate of change in day length that occurs during autumn at the latitude this species inhabits in nature. The results indicate that neurochemical lesions of the IGL alter both the pattern of circadian entrainment and photoperiodic responsiveness of Siberian hamsters to an SNP. Both intact and IGL-lesioned hamsters exhibited testicular regression in shortening day lengths, but only IGL-intact hamsters exhibited seasonal pelage molt. PMID:15518639

  2. Autonomic Nervous Dysfunction in Hamsters Infected with West Nile Virus

    PubMed Central

    Wang, Hong; Siddharthan, Venkatraman; Hall, Jeffery O.; Morrey, John D.

    2011-01-01

    Clinical studies and case reports clearly document that West Nile virus (WNV) can cause respiratory and gastrointestinal (GI) complications. Other functions controlled by the autonomic nervous system may also be directly affected by WNV, such as bladder and cardiac functions. To investigate how WNV can cause autonomic dysfunctions, we focused on the cardiac and GI dysfunctions of rodents infected with WNV. Infected hamsters had distension of the stomach and intestines at day 9 after viral challenge. GI motility was detected by a dye retention assay; phenol red dye was retained more in the stomachs of infected hamsters as compared to sham-infected hamsters. The amplitudes of electromygraphs (EMGs) of intestinal muscles were significantly reduced. Myenteric neurons that innervate the intestines, in addition to neurons in the brain stem, were identified to be infected with WNV. These data suggest that infected neurons controlling autonomic function were the cause of GI dysfunction in WNV-infected hamsters. Using radiotelemetry to record electrocardiograms and to measure heart rate variability (HRV), a well-accepted readout for autonomic function, we determined that HRV and autonomic function were suppressed in WNV-infected hamsters. Cardiac histopathology was observed at day 9 only in the right atrium, which was coincident with WNV staining. A subset of WNV infected cells was identified among cells with hyperplarization-activated cyclic nucleotide-gated potassium channel 4 (HCN4) as a marker for cells in the sinoatrial (SA) and atrioventricular (AV) nodes. The unique contribution of this study is the discovery that WNV infection of hamsters can lead to autonomic dysfunction as determined by reduced HRV and reduced EMG amplitudes of the GI tract. These data may model autonomic dysfunction of the human West Nile neurological disease. PMID:21573009

  3. MELIOIDOSIS: PATHOGENESIS AND IMMUNITY IN MICE AND HAMSTERS

    PubMed Central

    Dannenberg, Arthur M.; Scott, Eva M.

    1958-01-01

    The pathogenesis of acute respiratory melioidosis mice and hamsters is described. Inhaled organisms giving rise to lesions seemed to be first engulfed by the mononuclear alveolar phagocytes, but in less than 1 day polymorphonuclear cells made their appearance. In spite of this defense reaction, the bacteria continued to multiply and their products caused focal necrosis. These foci enlarged and gave rise to septicemia, toxemia, and eventually death, which usually occurred in 3 to 10 days depending on the dose. Melioidosis, is, therefore, an acute septicotoxemic disease resembling plague and anthrax in this respect. In hamsters the disease process developed more rapidly than in mice and death occurred sooner. The course of the disease in hamsters was sometimes complicated by intraglomerular deposits resembling "fibrinoid," which were similar to those of the generalized Shwartzman phenomenon. This phenomenon may have been an indirect cause of both the perifocal hemorrhage and the extremely large number of bacteria in some of the hamster lesions. When low infecting doses of organisms were employed, mice, but not hamsters, developed a chronic type of disease, lasting 2 to 8 weeks. This was characterized by large abscesses in the spleen or lung, marked proliferation of mononuclear phagocytes and plasma cells, and increased immunity against reinfection (about 40-fold against respiratory challenge). When mice and hamsters inhaled high infecting doses of organisms, a peracute disease resulted with death in 1 to 3 days. Increased numbers of bacteria were observed in the lesions, and the histological changes in the spleen resembled those following the intravenous injection of Malleomyces pseudomallei toxin or the intramuscular injection of large doses of cortisone. These changes were characterized by a swelling of the phagocytes of the white pulp with nuclear debris. The peracute, the acute, and the chronic forms of melioidosis in mice are similar to analogous clinical forms found in man. PMID:13481262

  4. Maternal Photoperiodic History Affects Offspring Development in Syrian Hamsters

    PubMed Central

    Beery, Annaliese K.; Paul, Matthew J.; Routman, David M.; Zucker, Irving

    2009-01-01

    During the first 7 weeks of postnatal life, short day lengths inhibit the onset of puberty in many photoperiodic rodents, but not in Syrian hamsters. In this species, timing of puberty and fecundity are independent of the early postnatal photoperiod. Gestational day length affects postnatal reproductive development in several rodents; its role in Syrian hamsters has not been assessed. We tested the hypothesis that cumulative effects of pre- and postnatal short day lengths would restrain gonadal development in male Syrian hamsters. Males with prenatal short day exposure were generated by dams transferred to short day lengths 6 weeks, 3 weeks, and 0 weeks prior to mating. Additional groups were gestated in long day lengths and transferred to short days at birth, at 4 weeks of age, or not transferred (control hamsters). In pups of dams exposed to short day treatment throughout gestation, decreased testis growth was apparent by 3 weeks and persisted through 9 weeks of age, at which time maximum testis size was attained. A subset of males (14%), whose dams had been in short days for 3 to 6 weeks prior to mating displayed pronounced delays in testicular development, similar to those of other photoperiodic rodents. This treatment also increased the percentage of male offspring that underwent little or no gonadal regression postnatally (39%). By 19 weeks of age, males housed in short days completed spontaneous gonadal development. After prolonged long day treatment to break refractoriness, hamsters that initially were classified as nonregressors underwent testicular regression in response to a 2nd sequence of short day lengths. The combined action of prenatal and early postnatal short day lengths diminishes testicular growth of prepubertal Syrian hamsters no later than the 3rd week of postnatal life, albeit to a lesser extent than in other photoperiodic rodents. PMID:18838610

  5. Optimization of Cryoprotectant Loading into Murine and Human Oocytes

    PubMed Central

    Karlsson, Jens O.M.; Szurek, Edyta A.; Higgins, Adam Z.; Lee, Sang R.; Eroglu, Ali

    2014-01-01

    Loading of cryoprotectants into oocytes is an important step of the cryopreservation process, in which the cells are exposed to potentially damaging osmotic stresses and chemical toxicity. Thus, we investigated the use of physics-based mathematical optimization to guide design of cryoprotectant loading methods for mouse and human oocytes. We first examined loading of 1.5 M dimethylsulfoxide (Me2SO) into mouse oocytes at 23°C. Conventional one-step loading resulted in rates of fertilization (34%) and embryonic development (60%) that were significantly lower than those of untreated controls (95% and 94%, respectively). In contrast, the mathematically optimized two-step method yielded much higher rates of fertilization (85%) and development (87%). To examine the causes for oocyte damage, we performed experiments to separate the effects of cell shrinkage and Me2SO exposure time, revealing that neither shrinkage nor Me2SO exposure single-handedly impairs the fertilization and development rates. Thus, damage during one-step Me2SO addition appears to result from interactions between the effects of Me2SO toxicity and osmotic stress. We also investigated Me2SO loading into mouse oocytes at 30°C. At this temperature, fertilization rates were again lower after one-step loading (8%) in comparison to mathematically optimized two-step loading (86%) and untreated controls (96%). Furthermore, our computer algorithm generated an effective strategy for reducing Me2SO exposure time, using hypotonic diluents for cryoprotectant solutions. With this technique, 1.5 M Me2SO was successfully loaded in only 2.5 min, with 92% fertilizability. Based on these promising results, we propose new methods to load cryoprotectants into human oocytes, designed using our mathematical optimization approach. PMID:24246951

  6. Aflatoxin B1 is toxic to porcine oocyte maturation.

    PubMed

    Liu, Jun; Wang, Qiao-Chu; Han, Jun; Xiong, Bo; Sun, Shao-Chen

    2015-07-01

    As a toxic secondary metabolite of Aspergillus species, Aflatoxin B1 (AFB1) is a major food and feed contaminant in tropical and sub-tropical regions with high temperature and humidity. It has been reported to be toxic to the female reproductive system in laboratory and domestic animals. In the present study, the influence of acute exposure to AFB1 (10 and 50 ?M, 44h) on porcine oocyte maturation and its possible mechanism were investigated. The maturation rates of oocytes decreased significantly in the presence of 50 ?M of AFB1. Cell cycle analysis showed that most oocytes were arrested at germinal vesicle breakdown or meosis I stage. However, actin assembly, spindle structure and chromosome alignment were not disrupted after exposure to 50 ?M AFB1. Further study showed that DNA methylation levels increased in treated oocytes (50 ?M). Histone methylation levels were also analysed after treatment (50 ?M): H3K27me3 and H3K4me2 levels decreased, whereas H3K9me3 level increased, indicating that epigenetic modification was affected. AFB1 treatment (50 ?M) also induced oxidative stress and further led to autophagy, as shown by accumulation of reactive oxygen species, up-regulated LC3 protein expression and increased mRNA levels of ATG3, ATG5 and ATG7. Annexin V-FITC staining assay revealed that AFB1 treatment (50 ?M) resulted in oocyte early apoptosis, which was confirmed by increased Bak, Bax, Bcl-xl mRNA levels. Collectively, our results suggest that AFB1 disrupts porcine oocyte maturation through changing epigenetic modifications as well as inducing oxidative stress, excessive autophagy and apoptosis. PMID:25778688

  7. Photodynamic therapy of hamster Greene melanoma in vitro and in vivo using bacteriochlorin-a as photosensitizer

    NASA Astrophysics Data System (ADS)

    Schuitmaker, J. J.; Van Best, Jaap A.; van Delft, J. L.; Jannink, J. E.; Oosterhuis, J. A.; Vrensen, Gijs F.; Ms Wolff-Rouendaal, Didi; Dubbelman, T. M.

    1996-01-01

    Efficient photodynamic therapy (PDT) of malignant melanoma may be possible with photosensitizers having absorption maxima in the far-red region e.g., above 700 nm. Bacteriochlorin a (BCA), a non toxic derivative of bacteriochlorphyllin a, has a high molecular absorption coefficient (32.000 M-1.cm-1) at 760 nm. At this wavelength tissue penetration of light is almost optimal and melanin absorption is relatively low. In several series of experiments BCA was proven to be a very effective photosensitizer, in vitro and in vivo. It is preferentially retained in experimental hamster Greene melanoma, rhabdomyosarcoma, RIF- and mamma tumors. Its fluorescence can be detected in vivo, thus enabling early tumor detection and it is rapidly cleared from the tissues which promises no, or minor skin photosensitivity. The effects of BCA-PDT were studied in vitro and in vivo using the heavily pigmented Hamster Greene Melanoma (HGM) cell line as a model. In vitro it was found that the uptake of BCA was time, concentration and temperature dependant. Upon illumination (10 Mw/cm2, 756 nm) after incubation with 2.5 (mu) g/ml BCA for 1 h, almost complete cell kill was obtained within seconds. Hamster Greene Melanoma implanted in the anterior eye chamber of rabbits is an accepted in vivo model for ocular melanoma. The effects of BCA-PDT using this model were studied by light- and electron microscopy. Immediately after PDT intracellular spaces were enlarged and blood vessels were clotted with swollen erythrocytes. Electron microscopy showed fused inner and outer membranes and affected cristae mitchondriales of some mitochondria. With time, the severity of tissue and cell damage increased. One day after irradiation tumor growth had stopped; fluorescein angiography showed non perfusion of the tumor. Histopathology showed almost complete tumor necrosis with occasionally viable cells at the tumor periphery. It is concluded that the direct mitochondrial damage and the vascular damage both contribute to BCA-PDT induced tumor necrosis.

  8. Asbestos cement dust inhalation by hamsters.

    PubMed

    Wehner, A P; Dagle, G E; Cannon, W C; Buschbom, R L

    1978-12-01

    Two groups of 96 male Syrian golden hamsters were exposed to respirable asbestos cement aerosol at concentrations of approximately 1 and approximately 10 micrograms/liter, respectively, 3 hours/day, 5 days/week. Average fiber counts ranged from 5 to about 120 fibers/cm3. Each group was randomly divided into six subgroups of 16 animals. The first subgroup was sacrificed after 3 months of exposure, the second after 6 months, and the third after 15 months. The fourth subgroup was withdrawn from exposure after 3 months, observed for an additional 3 months, and then sacrificed. The fifth and sixth subgroups were withdrawn after 3 and 6 months of exposure, respectively, and maintained for observation up to the 15-month exposure point of the third subgroup at which time all surviving animals were sacrificed. All other experimental procedures were similar to those delineated in a previous publication describing the development of an animal model, techniques, and an exposure system for asbestos cement dust inhalation (A. P. Wehner, G. E. Dagle, and W. C. Cannon, 1978, Environ. Res. 16, 393-407). The asbestos cement exposures had no significant effect on body weight and mortality of the animals. Higher aerosol concentration and longer exposure times increased the number of macrophages and ferruginous bodies found in the lungs of the exposed animals. Recovery periods had no effect on the incidence of macrophages and ferruginous bodies. The incidence of very slight to slight fibrosis in the animals sacrificed after 15 months of exposure shows a significant (P less than 0.01) trend when the untreated control group and the 1 and 10 microgram/liter dose level groups are compared, indicating a dose-response relationship. Development of minimal fibrosis continued in animals withdrawn from exposure. No primary carcinomas of the lung and respiratory tract and no mesotheliomas were found. PMID:318525

  9. Skin penetration of silica microparticles.

    PubMed

    Boonen, J; Baert, B; Lambert, J; De Spiegeleer, B

    2011-06-01

    Knowledge about skin penetration of nano- and microparticles is essential for the development of particle-core drug delivery systems and toxicology. A large number of studies have been devoted to metallic particle penetration. However, little work has been published about the importance of chemical material properties of the particles and the skin penetration effect of the applied formulation. Here, we investigated the penetration of 3 microm silica particles in water and in a 65% ethanolic plant extract on ex vivo human skin using scanning electron microscopy. Contrary to most other microsphere skin studies, we observed for the first time that 3 microm silica particles can penetrate the living epidermis. Moreover, when formulated in the ethanolic medium, particles even reach the dermis. The deviating chemical properties of silica compared to previously investigated microparticles (titanium dioxide, zinc oxide) and confounding effect of the formulation in which the silica microparticles are presented, is thus demonstrated. PMID:21699089

  10. An Earth Penetrating Modeling Assessment

    SciTech Connect

    Stokes, E; Yarrington, P; Glenn, L

    2005-06-21

    Documentation of a study to assess the capability of computer codes to predict lateral loads on earth penetrating projectiles under conditions of non-normal impact. Calculations simulated a set of small scale penetration tests into concrete targets with oblique faces at angles of 15 and 30 degrees to the line-of-flight. Predictive codes used by the various calculational teams cover a wide range of modeling approaches from approximate techniques, such as cavity expansion, to numerical methods, such as finite element codes. The modeling assessment was performed under the auspices of the Phenomenology Integrated Product Team (PIPT) for the Robust Nuclear Earth Penetrator Program (RNEP). Funding for the penetration experiments and modeling was provided by multiple earth penetrator programs.

  11. Isolation and identification of normal killer cells from Syrian hamsters

    SciTech Connect

    Matveeva, V.A.; Klyuchareva, T.E.

    1986-09-01

    This paper gives data on isolation of normal killer cells from the blood and various tissues of Syrian hamsters in a Percoll density gradient and their identification on the basis of morphologic criteria and cytotoxic activity (CTA). CTA of the isolated cells was studied in the cytotoxic test with target cells of a human MOLT-4 thymoma cell labeled with /sup 51/Cr. Isolation of large granular lymphocytes from blood, spleen, and bone marrow of Syrian hamsters in Percoll density gradient is shown in the results of five experiments used for cells of each type.

  12. AMS 102: QUIZ 2 1. The population of long-tailed hamster in eastern Texas has been de-

    E-print Network

    Retakh, Alexander

    AMS 102: QUIZ 2 SOLUTIONS 1. The population of long-tailed hamster in eastern Texas has been de of the hamster's natural habitat. Two statistical studies were conducted that, on the year-by-year basis (1) compared hamster population with the area of human settlement, (2) compared hamster population with annual

  13. A Rapid Western Blotting Protocol for the Xenopus Oocyte

    PubMed Central

    Lin-Moshier, Yaping; Marchant, Jonathan S.

    2014-01-01

    Often experimentalists require a quantitative assessment of the levels of heterologously expressed proteins to best interpret changed Ca2+ signaling patterns. Here, we detail a rapid and convenient western blotting method for individual Xenopus oocytes. The method exploits recently introduced rapid blotting systems, commercially available from Invitrogen (iBlot) or Bio-Rad (Trans-Blot Turbo). The key advantage is speed: from live cell to transferred membrane in <1 h. Therefore, oocytes can be conveniently processed for western blotting to assess relative expression levels, even after a long day of Ca2+ imaging experiments. PMID:23457341

  14. Mammalian oocytes are targets for prostaglandin E2 (PGE2) action

    PubMed Central

    2010-01-01

    Background The ovulatory gonadotropin surge increases synthesis of prostaglandin E2 (PGE2) by the periovulatory follicle. PGE2 actions on granulosa cells are essential for successful ovulation. The aim of the present study is to determine if PGE2 also acts directly at the oocyte to regulate periovulatory events. Methods Oocytes were obtained from monkeys and mice after ovarian follicular stimulation and assessed for PGE2 receptor mRNA and proteins. Oocytes were cultured with vehicle or PGE2 and assessed for cAMP generation, resumption of meiosis, and in vitro fertilization. Results Germinal vesicle intact (GV) oocytes from both monkeys and mice expressed mRNA for the PGE2 receptors EP2, EP3, and EP4. EP2 and EP4 proteins were detected by confocal microscopy in oocytes of both species. Monkey and mouse oocytes responded to PGE2 as well as agonists selective for EP2 and EP4 receptors with elevated cAMP, consistent with previous identification of EP2 and EP4 as G?s/adenylyl cyclase coupled receptors. Incubation of mouse GV stage oocytes with PGE2 delayed oocyte nuclear maturation in vitro, but PGE2 treatment did not alter the percentage of mouse oocytes that fertilized successfully. PGE2 treatment also decreased the percentage of monkey oocytes that resumed meiosis in vitro. In contrast with mouse oocytes, the percentage of monkey oocytes which fertilized in vitro was lower after treatment with PGE2. Monkey oocytes with intact cumulus showed delayed nuclear maturation, but fertilization rate was not affected by PGE2 treatment. Conclusions Monkey and mouse oocytes express functional PGE2 receptors. PGE2 acts directly at mammalian oocytes to delay nuclear maturation. Surrounding cumulus cells modulate the effect of PGE2 to alter subsequent fertilization. PMID:21040553

  15. Electromagnetic Field Penetration Studies

    NASA Technical Reports Server (NTRS)

    Deshpande, M.D.

    2000-01-01

    A numerical method is presented to determine electromagnetic shielding effectiveness of rectangular enclosure with apertures on its wall used for input and output connections, control panels, visual-access windows, ventilation panels, etc. Expressing EM fields in terms of cavity Green's function inside the enclosure and the free space Green's function outside the enclosure, integral equations with aperture tangential electric fields as unknown variables are obtained by enforcing the continuity of tangential electric and magnetic fields across the apertures. Using the Method of Moments, the integral equations are solved for unknown aperture fields. From these aperture fields, the EM field inside a rectangular enclosure due to external electromagnetic sources are determined. Numerical results on electric field shielding of a rectangular cavity with a thin rectangular slot obtained using the present method are compared with the results obtained using simple transmission line technique for code validation. The present technique is applied to determine field penetration inside a Boeing-757 by approximating its passenger cabin as a rectangular cavity filled with a homogeneous medium and its passenger windows by rectangular apertures. Preliminary results for, two windows, one on each side of fuselage were considered. Numerical results for Boeing-757 at frequencies 26 MHz, 171-175 MHz, and 428-432 MHz are presented.

  16. Live birth after ICSI of micro-TESE-retrieved spermatozoa into in vitro-matured oocytes.

    PubMed

    Son, Weon-Young; Chung, Jin-Tae; Chan, Peter T K; Tan, Seang Lin

    2011-01-01

    This case report describes a live birth resulting from intracytoplasmic sperm injection (ICSI) of spermatozoa retrieved by microdissection testicular sperm extraction (micro-TESE) into oocytes produced from human chorionic gonadotropin-primed in vitro maturation (IVM) cycles. In the IVM treatment, a total of 30 oocytes (1 mature and 29 immature oocytes) were retrieved. Following IVM, 9 oocytes had matured. A total of 4 oocytes were fertilized after ICSI with the husband's micro-TESE spermatozoa and 4 embryos were transferred into the uterus on day 3. A healthy boy weighing 2500 g was born at 35.5 weeks of gestation. PMID:20705792

  17. Steroid hormones promote bovine oocyte growth and connection with granulosa cells.

    PubMed

    Makita, Miho; Miyano, Takashi

    2014-09-01

    Many approaches have been investigated for growing oocytes in vitro in mammals. To support oocyte growth in vitro, the culture systems must meet certain conditions for maintaining connections between oocytes and surrounding granulosa cells. The aims of this study were to determine the effects of combinations of 17?-estradiol (E2) and androstenedione (A4) on in vitro growth of bovine oocytes and to determine the number of connections between the oocyte and granulosa cells. Oocyte-granulosa cell complexes (OGCs) collected from early antral follicles (0.4-0.7 mm in diameter) were cultured for 14 days in a medium with different concentrations of E2 and A4, either alone or in combinations. We then assessed the number of transzonal projections (TZPs), which extend from granulosa cells through the zona pellucida to the oolemma. During in vitro growth culture, OGC structures were maintained in the medium with steroid hormones. The mean diameter of oocytes grown in the medium with both E2 and A4 was increased from 95.8 ?m to around 120 ?m, larger than oocytes grown without steroid hormones (109.9 ?m) and similar in size to in vivo fully grown oocytes (119.4 ?m) from 4- to 6-mm antral follicles. In subsequent in vitro maturation culture (22 hours), 30% (12 of 40) and 34% (14 of 41) of oocytes grown with E2 or A4 alone, respectively, matured to metaphase II; meanwhile, oocytes grown with a combination of E2 and A4 matured to metaphase II at a high rate (58%, 23 of 40). Growing oocytes isolated from early antral follicles had many uniformly distributed TZPs throughout the zona pellucida. After 14 days of culture, there was a significant decrease in the number of TZPs in oocytes grown without steroid hormones, whereas the number of TZPs was maintained in oocytes grown with steroid hormones. In particular, oocytes grown with E2 alone or with a combination of E2 and A4 had numbers of TZPs similar to oocytes before growth culture. In conclusion, a combination of E2 and A4 maintained the connections between oocytes and granulosa cells during in vitro growth culture of bovine oocytes for 14 days, resulting in the complete oocyte growth and the acquisition of meiotic competence in more than half the oocytes. PMID:24985562

  18. Cooperative Transmembrane Penetration of Nanoparticles

    PubMed Central

    Zhang, Haizhen; Ji, Qiuju; Huang, Changjin; Zhang, Sulin; Yuan, Bing; Yang, Kai; Ma, Yu-qiang

    2015-01-01

    Physical penetration of lipid bilayer membranes presents an alternative pathway for cellular delivery of nanoparticles (NPs) besides endocytosis. NPs delivered through this pathway could reach the cytoplasm, thereby opening the possibility of organelle-specific targeting. Herein we perform dissipative particle dynamics simulations to elucidate the transmembrane penetration mechanisms of multiple NPs. Our simulations demonstrate that NPs’ translocation proceeds in a cooperative manner, where the interplay of the quantity and surface chemistry of the NPs regulates the translocation efficiency. For NPs with hydrophilic surfaces, the increase of particle quantity facilitates penetration, while for NPs with partly or totally hydrophobic surfaces, the opposite highly possibly holds. Moreover, a set of interesting cooperative ways, such as aggregation, aggregation-dispersion, and aggregation-dispersion-reaggregation of the NPs, are observed during the penetration process. We find that the penetration behaviors of multiple NPs are mostly dominated by the changes of the NP-membrane force components in the membrane plane direction, in addition to that in the penetration direction, suggesting a different interaction mechanism between the multiple NPs and the membrane compared with the one-NP case. These results provide a fundamental understanding in the underlying mechanisms of cooperative penetration of NPs, and shed light on the NP-based drug and gene delivery. PMID:26013284

  19. Cooperative transmembrane penetration of nanoparticles.

    PubMed

    Zhang, Haizhen; Ji, Qiuju; Huang, Changjin; Zhang, Sulin; Yuan, Bing; Yang, Kai; Ma, Yu-Qiang

    2015-01-01

    Physical penetration of lipid bilayer membranes presents an alternative pathway for cellular delivery of nanoparticles (NPs) besides endocytosis. NPs delivered through this pathway could reach the cytoplasm, thereby opening the possibility of organelle-specific targeting. Herein we perform dissipative particle dynamics simulations to elucidate the transmembrane penetration mechanisms of multiple NPs. Our simulations demonstrate that NPs' translocation proceeds in a cooperative manner, where the interplay of the quantity and surface chemistry of the NPs regulates the translocation efficiency. For NPs with hydrophilic surfaces, the increase of particle quantity facilitates penetration, while for NPs with partly or totally hydrophobic surfaces, the opposite highly possibly holds. Moreover, a set of interesting cooperative ways, such as aggregation, aggregation-dispersion, and aggregation-dispersion-reaggregation of the NPs, are observed during the penetration process. We find that the penetration behaviors of multiple NPs are mostly dominated by the changes of the NP-membrane force components in the membrane plane direction, in addition to that in the penetration direction, suggesting a different interaction mechanism between the multiple NPs and the membrane compared with the one-NP case. These results provide a fundamental understanding in the underlying mechanisms of cooperative penetration of NPs, and shed light on the NP-based drug and gene delivery. PMID:26013284

  20. Projectile penetration into ballistic gelatin.

    PubMed

    Swain, M V; Kieser, D C; Shah, S; Kieser, J A

    2014-01-01

    Ballistic gelatin is frequently used as a model for soft biological tissues that experience projectile impact. In this paper we investigate the response of a number of gelatin materials to the penetration of spherical steel projectiles (7 to 11mm diameter) with a range of lower impacting velocities (<120m/s). The results of sphere penetration depth versus projectile velocity are found to be linear for all systems above a certain threshold velocity required for initiating penetration. The data for a specific material impacted with different diameter spheres were able to be condensed to a single curve when the penetration depth was normalised by the projectile diameter. When the results are compared with a number of predictive relationships available in the literature, it is found that over the range of projectiles and compositions used, the results fit a simple relationship that takes into account the projectile diameter, the threshold velocity for penetration into the gelatin and a value of the shear modulus of the gelatin estimated from the threshold velocity for penetration. The normalised depth is found to fit the elastic Froude number when this is modified to allow for a threshold impact velocity. The normalised penetration data are found to best fit this modified elastic Froude number with a slope of 1/2 instead of 1/3 as suggested by Akers and Belmonte (2006). Possible explanations for this difference are discussed. PMID:24184862

  1. Gene Expression Profiling of Human Oocytes Developed and Matured In Vivo or In Vitro

    PubMed Central

    Virant-Klun, Irma; Knez, Katja; Tomazevic, Tomaz; Skutella, Thomas

    2013-01-01

    The quality of the human oocyte determines the success of fertilization and affects the consequent embryo development, pregnancy and birth; it therefore serves as a basis for human reproduction and fertility. The possibility to evaluate oocyte quality in the in vitro fertilization programme is very limited. The only criterion which is commonly used to evaluate oocyte quality is its morphology. There is a mass of oocytes in the in vitro fertilization programme which are not fertilized in spite of normal morphology. In the past, several attempts focused on oocyte gene expression profiling by different approaches. The results elucidated groups of genes related to the human oocyte. It was confirmed that some factors, such as oocyte in vitro maturation, are detectable at the molecular level of human oocytes and their polar bodies in terms of gene expression profile. Furthermore, the first genetic evaluations of oocyte-like cells developed in vitro from human stem cells of different origin were performed showing that these cells express some genes related to oocytes. All these findings provide some new knowledge and clearer insights into oocyte quality and oogenesis that might be introduced into clinical practice in the future. PMID:23509795

  2. Advances in oocyte cryopreservation technology will eventually blur the ethical and moral boundaries between compensated egg sharing and commercialized oocyte donation.

    PubMed

    Heng, Boon Chin

    2006-03-01

    Compensated egg sharing was originally conceived as a patient self-help co-operative scheme to avoid overt 'commodification' of donor oocytes and prevent doctors and medical institutions from acting as 'brokers' of donated human material. As such, egg sharing is an ethically justifiable and much-preferred alternative to commercialized oocyte donation. However, recent advances in oocyte cryopreservation technology are likely to blur the ethical and moral boundaries between compensated egg sharing and commercialized oocyte donation. The banking of cryopreserved oocytes would negate the requirement for donors and recipients in egg sharing to have co-ordinated and synchronized treatment cycles. Instead, fertility doctors and medical institutions can now offer subsidized fertility treatment upfront to any patient willing to donate a portion of her retrieved cohort of oocytes for banking and subsequent donation. Thus, more opportunity is now open for them to act as 'middle-man' to broker the transaction of oocytes between donor and recipient, which would inevitably result in overt 'commodification' of donated human material. Administrative and processing fees will de finitely be billed to prospective recipients, for banking and storage of the cryopreserved oocytes, which would mean that a direct profit can now be made from the transaction of oocytes between donor and recipient. PMID:16569309

  3. Calcium transients during early development in single starfish (Asterias forbesi) oocytes

    SciTech Connect

    Eisen, A.; Reynolds, G.T.

    1984-11-01

    Maturation and fertilization of the starfish oocyte are putative calcium-dependent events. The authors have investigated the spatial distribution and temporal dynamics of this calcium dependence in single oocytes of Asterias forbesi. They used the calcium photoprotein, aequorin, in conjunction with a microscope-photomultiplier and microscope-image intensifier. Surprisingly, in contrast to earlier work with Marasthenias glacialis, there is no detectable increase in intracellular-free calcium in the oocyte of A. forbesi in response to the maturation hormone 1-methyl adenine. During fertilization of the same, matured, A. forbesi oocyte there is a large increase in intracellular-free calcium. The calcium concentration increases to approx.1 ..mu..M at the point of insemination and the region of elevated free calcium expands across the oocyte in approx.20 s (17-19/sup 0/C). After the entire oocyte reaches an elevated concentration of free calcium, the concentration decreases uniformly throughout the oocyte over the next several minutes.

  4. CARCINOGENIC POTENTIAL OF ROTENONE. PHASE I: DIETARY ADMINISTRATION TO HAMSTERS

    EPA Science Inventory

    Studies were performed to evaluate the potential carcinogenicity rotenone in the Syrian Golden hamster. Several ancillary range-finding studies were carried out including 14-day feeding trials and a reproduction experiment. The latter experiment indicated that rotenone at a level...

  5. Testicular Hypoplasia and Epididymal Cysts in the Syrian Hamster

    Microsoft Academic Search

    Humberto Granados; Henrik Dam

    1948-01-01

    WE have observed certain definite changes in the testes of some inbred hamsters. These changes are characterized by a striking testicular hypoplasia, mostly bilateral. Such testes, represented sometimes by structures which are almost invisible to the naked eye, appeared very pale, with an apparent lack of normal vascularization. Their individual weight was only 2-306 mgm., as compared with a testicular

  6. PULMONARY CELL POPULATIONS IN HAMSTERS MAINTAINED UNDER EGYPTIAN LABORATORY CONDITIONS

    EPA Science Inventory

    The study was conducted to obtain baseline values for pulmonary cells in golden hamsters (Mesocricetus auratus) bred and maintained under the laboratory conditions of Al-Azhar University in Egypt. An improvised technique is presented for measuring pulmonary cells obtained by lung...

  7. Circadian phase response curves for dark pulses in the hamster

    Microsoft Academic Search

    Ziad Boulos; Benjamin Rusak

    1982-01-01

    Hamsters maintained under constant illumination were exposed to 2- or 6-h pulses of darkness at various phases of their circadian activity rhythms. When presented around the time of activity onset, the pulses resulted in phase advances, and when presented toward the end of daily activity, they resulted in phase delays. Since others have shown that light pulses presented at the

  8. Congenital Anomalies Induced in Hamster Embryos with Ribavirin

    Microsoft Academic Search

    Lawrence Kilham; Virgil H. Ferm

    1977-01-01

    Ribavirin, when given to pregnant hamsters in relatively small single doses, induces congenital anomalies of limbs, ribs, eyes, and central nervous system, as well as fetal deaths, On the basis of these findings, caution should be used in giving ribavirin to women of child-bearing age.

  9. RELATIONSHIP BETWEEN AUTONOMIC AND BEHAVIORAL THERMOREGULATION IN THE GOLDEN HAMSTER

    EPA Science Inventory

    Preferred ambient temperature (Ta) of male golden hamsters (Mesocricitus auratus) was measured repeatedly by placing the animals in a temperature gradient for 80 min. A total of 180 observations were made during the last 20 min of treatment in the gradient. The mean preferred Ta ...

  10. A Mutation of the Circadian System in Golden Hamsters

    Microsoft Academic Search

    Martin R. Ralph; Michael Menaker

    1988-01-01

    A mutation has been found that dramatically shortens the period of the circadian locomotor rhythm of golden hamsters. The pattern of inheritance of this mutation suggests that it occurred at a single, autosomal locus (tau). Wild-type animals have rhythms with free-running periods averaging about 24 hours; animals heterozygous for the mutation have periods of about 22 hours, whereas homozygous animals

  11. Repair of human sperm chromosome aberrations in the hamster egg

    Microsoft Academic Search

    A. Genescà; M. R. Caballín; R. Miró; J. Benet; J. R. Germà; J. Egozcue

    1992-01-01

    In order to study the repair capacity of fertilized hamster eggs for the lesions present or induced in human sperm, we have examined the potentiating effect of caffeine, a DNA repair inhibitor, on the frequency and types of sperm chromosome aberrations. Sperm samples were donated by an individual treated with chemotherapy for a testicular cancer 3 years previously. Exposure of

  12. Adenylylcyclase Supersensitization in -Opioid Receptor-transfected Chinese Hamster Ovary

    E-print Network

    Vogel, Zvi

    Adenylylcyclase Supersensitization in -Opioid Receptor-transfected Chinese Hamster Ovary Cells Following Chronic Opioid Treatment* (Received for publication, September 13, 1995) Tomer Avidor with rat -opioid receptor cDNA, we show that the -agonists morphine and [D-Ala2 , N-methyl-Phe4 ,Gly-ol5

  13. DOSE RESPONSE OF ELASTASE-INDUCED EMPHYSEMA IN HAMSTERS

    EPA Science Inventory

    Elastase-induced emhysema in hamsters was studied using pulmonary function tests in an effort to develop techniques for determining the effects of air pollutants on the progression of this disease. It appears that as little as 6 units of elastase produces mild emphysema in hamste...

  14. Photoperiodic Regulation of Compensatory Testicular Hypertrophy in Hamsters1

    Microsoft Academic Search

    Matthew J. Paul; Jin Ho Park; Teresa H. Horton; Maria I. Alvarez; Morgan K. Burke; Irving Zucker

    In mammals, removal of one testis results in compensatory testicular hypertrophy (CTH) of the remaining gonad. Although CTH is ubiquitous among juveniles of many species, laboratory rats, laboratory mice, and humans unilaterally castrated in adulthood fail to display CTH. We documented CTH in pre- and postpubertally hemi-castrated Syrian and Siberian hamsters and tested whether day length affects CTH in juvenile

  15. Cigarette smoke inhalation affects the reproductive system of female hamsters

    Microsoft Academic Search

    T. Magers; P. Talbot; G. DiCarlantonio; M. Knoll; D. Demers; I. Tsai; T. Hoodbhoy

    1995-01-01

    The purpose of this study was to determine if inhalation of mainstream (MS) or sidestream (SS) smoke affects the reproductive organs of female hamsters. Females inhaled smoke from one or two cigarettes twice per day for 30 d prior to mating using a smoking machine equipped for nose only breathing. Serum cotinine levels were within the ranges found in active

  16. Behavior evoked by electrical stimulation of the hamster superior colliculus

    Microsoft Academic Search

    D. P. M. Northmore; E. S. Levine; G. E. Schneider

    1988-01-01

    Syrian golden hamsters were implanted with fixed or moveable stimulating electrodes aimed at the superior colliculus (SC). Behavior was observed in response to trains of 0.1 ms pulses at 200 Hz while the animals were moving freely in an open arena or in their home cages. At threshold stimulating currents, the responses consisted almost entirely of freezing or contraversive turning,

  17. Glutamine protects Chinese Hamster Ovary cells from radiation killing

    Microsoft Academic Search

    Roger Winters; Richard Matthews; Nuran Ercal; Kalpana Krishnan

    1994-01-01

    Chinese Hamster Ovary (CHO) cells were propagated in vitro and exposed to varying doses of ionizing radiation. The surviving fraction of cells was determined, being found to be a function of the radiation dose. The cell survival curves obtained as a function of radiation dose were modified by the inclusion of varying doses of glutamine in the medium, with glutamine

  18. Molecular Phenotype of the Human Oocyte by PCR–SAGE

    Microsoft Academic Search

    Lorna Neilson; Ali Andalibi; Douglas Kang; Christos Coutifaris; Jerome F Strauss; Jo-Ann L Stanton; David P. L Green

    2000-01-01

    Consecutive application of PCR and serial analysis of gene expression (SAGE) was used to generate a catalog of ?50,000 SAGEtags from nine human oocytes. Matches for known genes were identified using the National Institutes of Health SAGEtag database. This database links directly to the UniGene database, providing rapid discrimination between SAGEtags that match known genes and expressed sequence tags and

  19. A Simplified Approach for Oocyte Enucleation in Mammalian Cloning

    PubMed Central

    Iuso, Domenico; Czernik, Marta; Zacchini, Federica

    2013-01-01

    Abstract Despite its success in almost all farm and laboratory animals, somatic cell nuclear transfer (SCNT) is still a low-efficiency technique. In this investigation, we determined the impact of each enucleation step on oocyte viability (assessed by parthenogenetic activation): Hoechst (HO) staining, cytochalasin B, ultraviolet (UV) exposure, and demecolcine. Our data showed that of all the factors analyzed, UV exposure impaired oocyte development (cleavage, 59% for untreated oocytes vs. 8% UV exposed; blastocyst stage, 32% untreated vs. 0% UV exposed). A minor toxicity was detected following demecolcine treatment (cleavage, 62%; blastocyst stage, 13%). Next, we compared HO/UV (canonical) and demecolcine-assisted enucleation (DAE), with a straight removal of metaphase chromosomes without any chemical or physical aid (straight enucleation). DAE improved the preimplantation development of sheep cloned embryos compared to HO/UV enucleation (cleavage, 38% vs. 19%; blastocysts, 17% vs. 4%), yet straight enucleation resulted in the highest cleavage and blastocysts rates (61% and 30%, respectively). We concluded that: (1) UV exposure harms sheep oocyte and embryo development; (2) DAE may represent an alternative approach, especially for unskilled operators; and (3) straight enucleation remains, in our estimation, the most reliable and least harmful protocol for SCNT. PMID:24219576

  20. Experience of freezing human oocytes using sodium-depleted media.

    PubMed

    Azambuja, R; Petracco, A; Okada, L; Michelon, J; Badalotti, F; Badalotti, M

    2011-01-01

    Human embryo cryopreservation techniques enable the storage of surplus embryos created during assisted reproduction procedures; however, the existence of these same surplus embryos has sparked further debate. What can be their fate once they are no longer desired by their parents or if the parents are deceased? Thus, the level of interest in the cryopreservation of oocytes has increased, as has the necessity for further scientific study. This study had the objective of reporting 10 years of experience of freezing and thawing human oocytes from patients who did not wish to freeze embryos. A total of 159 cycles using frozen–thawed oocytes were performed (mean age 33.7 years). Survival and fertilization rates were 57.4% and 67.2%, respectively. Cleavage rate was 88.4% and the pregnancy rate was 37.7%. Clinical pregnancy was observed in 43 cycles (27.0%) with 14.5% of transferred embryos implanted. These pregnancies delivered 19 boys and 23 girls, two pregnancies are ongoing and nine were miscarriages. The average gestational week was 37.6 weeks and birthweight was 2829.2 g. These data suggest that the use of frozen–thawed oocytes in IVF represents a reasonable alternative for those patients not comfortable with the cryopreservation of supernumerary embryos. PMID:21123115

  1. Aurelia aurita (Cnidaria) Oocytes' Contact Plate Structure and Development

    PubMed Central

    Adonin, Leonid S.; Shaposhnikova, Tatyana G.; Podgornaya, Olga

    2012-01-01

    One of the A. aurita medusa main mesoglea polypeptides, mesoglein, has been described previously. Mesoglein belongs to ZP-domain protein family and therefore we focused on A.aurita oogenesis. Antibodies against mesoglein (AB RA47) stain the plate in the place where germinal epithelium contacts oocyte on the paraffin sections. According to its position, we named the structure found the “contact plate”. Our main instrument was AB against mesoglein. ZP-domain occupies about half of the whole amino acid sequence of the mesoglein. Immunoblot after SDS-PAGE and AU-PAGE reveals two charged and high Mr bands among the female gonad germinal epithelium polypeptides. One of the gonads' polypeptides Mr corresponds to that of mesogleal cells, the other ones' Mr is higher. The morphological description of contact plate formation is the subject of the current work. Two types of AB RA47 positive granules were observed during progressive oogenesis stages. Granules form the contact plate in mature oocyte. Contact plate of A.aurita oocyte marks its animal pole and resembles Zona Pellucida by the following features: (1) it attracts spermatozoids; (2) the material of the contact plate is synthesized by oocyte and stored in granules; (3) these granules and the contact plate itself contain ZP domain protein(s); (4) contact plate is an extracellular structure made up of fiber bundles similar to those of conventional Zona Pellucida. PMID:23185235

  2. Oocyte-somatic cells interactions, lessons from Charlier et al.

    E-print Network

    Paris-Sud XI, Université de

    vertebrate species - a teleost fish, an amphibian, and two mammals - at similar key steps of developmental acquisition are genes involved in key processes such as cellular energy metabolism, cell including different LH-receptor activated signaling pathways [5-7]. In prophase I-arrested oocytes, meiosis

  3. In Vitro Grown Sheep Preantral Follicles Yield Oocytes with Normal Nuclear-Epigenetic Maturation

    PubMed Central

    Barboni, Barbara; Russo, Valentina; Cecconi, Sandra; Curini, Valentina; Colosimo, Alessia; Garofalo, Maria Luigia A.; Capacchietti, Giulia; Di Giacinto, Oriana; Mattioli, Mauro

    2011-01-01

    Background Assisted reproductive technologies allow to utilize a limited number of fully grown oocytes despite the presence in the ovary of a large pool of meiotically incompetent gametes potentially able to produce live births. In vitro folliculogenesis could be useful to recruit these oocytes by promoting their growth and differentiation. Methodology/Principal Findings In vitro folliculogenesis was performed starting from sheep preantral (PA) follicles to evaluate oocyte nuclear/epigenetic maturation. Chromatin configuration, quantification of global DNA methylation, and epigenetic remodelling enzymes were evaluated with immunocytochemistry, telomere elongation was assessed with the Q-FISH technique, while the DNA methylation status at the DMRs of maternally IGF2R and BEGAIN, and paternally H19 methylated imprinted genes was determined by bisulfite sequencing and COBRA. Specifically, 70% of PA underwent early antrum (EA) differentiation and supported in culture oocyte global DNA methylation, telomere elongation, TERT and Dnmt3a redistribution thus mimicking the physiological events that involve the oocyte during the transition from secondary to tertiary follicle. Dnmt1 anticipated cytoplasmic translocation in in vitro grown oocytes did not impair global and single gene DNA methylation. Indeed, the in vitro grown oocytes acquired a methylation profile of IGF2R and BEGAIN compatible with the follicle/oocyte stage reached, and maintained an unmethylated status of H19. In addition, the percentage of oocytes displaying a condensed chromatin configuration resulted lower in in vitro grown oocytes, however, their ability to undergo meiosis and early embryo development after IVF and parthenogenetic activation was similar to that recorded in EA follicle in vivo grown oocytes. Conclusions/Significance In conclusion, the in vitro folliculogenesis was able to support the intracellular/nuclear mechanisms leading the oocytes to acquire a meiotic and developmental competence. Thus, the in vitro culture may increase the availability of fertilizable oocytes in sheep, and become an in vitro translational model to investigate the mechanisms governing nuclear/epigenetic oocyte maturation. PMID:22132111

  4. Investigations into Monochloramine Biofilm Penetration

    EPA Science Inventory

    Biofilm in drinking water systems is undesirable. Free chlorine and monochloramine are commonly used as secondary drinking water disinfectants, but monochloramine is perceived to penetrate biofilm better than free chlorine. However, this hypothesis remains unconfirmed by direct b...

  5. Expression of epithelial Na channels in Xenopus oocytes

    PubMed Central

    1990-01-01

    Epithelial Na channel activity was expressed in oocytes from Xenopus laevis after injection of mRNA from A6 cells, derived from Xenopus kidney. Poly A(+) RNA was extracted from confluent cell monolayers grown on either plastic or permeable supports. 1-50 ng RNA was injected into stage 5-6 oocytes. Na channel activity was assayed as amiloride- sensitive current (INa) under voltage-clamp conditions 1-3 d after injection. INa was not detectable in noninjected or water-injected oocytes. This amiloride-sensitive pathway induced by the mRNA had a number of characteristics in common with that in epithelial cells, including (a) high selectivity for Na over K, (b) high sensitivity to amiloride with an apparent K1 of approximately 100 nM, (c) saturation with respect to external Na with an apparent Km of approximately 10 mM, and (d) a time-dependent activation of current with hyperpolarization of the oocyte membrane. Expression of channel activity was temperature dependent, being slow at 19 degrees C but much more rapid at 25 degrees C. Fractionation of mRNA on a sucrose density gradient revealed that the species of RNA inducing channel activity had a sedimentation coefficient of approximately 17 S. Treatment of filter-grown cells with 300 nM aldosterone for 24 h increased Na transport in the A6 cells by up to fivefold but did not increase the ability of mRNA isolated from those cells to induce channel activity in oocytes. The apparent abundance of mRNA coding for channel activity was 10-fold less in cells grown on plastic than in those grown on filters, but was increased two- to threefold by aldosterone. PMID:2170563

  6. Penetrant-Indication-Measuring Compass

    NASA Technical Reports Server (NTRS)

    Schaefer, Lloyd

    1991-01-01

    Modified drafting compass well suited to measurement of length of crack or width of area stained by penetrant-dye-inspection method. Equipped with any of variety of standard curved or straight pointed tips. Modification consists in coating tips with dye that fluoresces light pink under same ultraviolet inspection light causing penetrant dye to fluoresce yellow green. Used in locations inaccessible to conventional fluorescent comparator. Eliminates errors of optical distortion in comparator, also eliminates errors of interpolation.

  7. Laparoscopy in penetrating abdominal trauma.

    PubMed

    Uranues, Selman; Popa, Dorin Eugen; Diaconescu, Bogdan; Schrittwieser, Rudolph

    2015-06-01

    If morbidity and mortality are to be reduced in patients with penetrating abdominal trauma, first priority goes to prompt and accurate determination of peritoneal penetration and identification of the need for surgery. In this setting, laparoscopy may have an important impact on the rate of negative or non-therapeutic laparotomies. We analyzed indications and patient selection criteria for laparoscopy in penetrating trauma along with outcomes. The analysis focused on identification of peritoneal penetration and injuries to the diaphragm, small intestine, and mesentery. Results from the early phase of laparoscopy were compared with those from recent decades with more advanced laparoscopic equipment and instruments and more experienced surgeons. A systematic review of the role of laparoscopy in penetrating abdominal trauma shows a sensitivity ranging from 66.7 to 100 %, specificity from 33.3 to 100 % and accuracy from 50 to 100 %. Publications from the 1990s found trauma laparoscopy to be inadequate for detecting intestinal injuries and so to lead to missed injuries. Twenty-three of the 50 studies including the most recent ones report sensitivity, specificity, and accuracy of 100 %. Laparoscopy is more cost effective than negative laparotomy. Laparoscopy can be performed safely and effectively on stable patients with penetrating abdominal trauma. The most important advantages are reduction of morbidity, accuracy in detecting diaphragmatic and intestinal injuries, and elimination of prolonged hospitalization for observation, so reducing the length of stay and increasing cost effectiveness. PMID:25446491

  8. Demonstration of survivable space penetrator

    NASA Astrophysics Data System (ADS)

    Church, Philip; Huntington-Thresher, William; Bruce, Alan; Penny, Nick; Smith, Alan; Gowan, Rob

    2012-03-01

    This work was performed in support of MoonLITE which is a proposed UK space mission to the moon. The basic premise is to deploy 4 instrumented penetrators, one each on the near-side, farside and at the poles of the moon, with an impact velocity of approximately 300m/s. The primary science aims are to set up a passive seismometer network, investigate the presence of water and volatiles and determine thermal gradients in the lunar soil (i.e. regolith). A key requirement is that the penetrator shell survives the impact together with the instrument payload and supporting subsystems. The material chosen for the penetrator shell was 7075 aluminium alloy, which is a good compromise between high compressive strength and low mass. The baseline penetrator design was evaluated and refined using the DYNA3D hydrocode to determine the survivability of the penetrator in sand at an impact velocity of 300m/s and an attack angle of 8°. The simulations predicted that the penetrator design would survive this severe impact condition which was confirmed by experiments on the Pendine rocket test track.

  9. Demonstration of Survivable Space Penetrator

    NASA Astrophysics Data System (ADS)

    Church, P.; Huntington-Thresher, W.; Penny, N.; Bruce, A.; Smith, A.; Gowan, R.

    2009-06-01

    This work was performed in support of MoonLITE which is a proposed UK space mission to the moon. The basic premise is to deploy 4 instrumented penetrators, one each on the near-side, far-side and at the poles of the moon, with an impact velocity of approximately 300m/s. The primary science aims are to set up a passive seismometer network, investigate the presence of water and volatiles and determine thermal gradients in the lunar soil (i.e. regolith). A key requirement is that the penetrator shell survives the impact together with the instrument payload and supporting subsystems. The material chosen for the penetrator shell was 7075 aluminum alloy, which is a good compromise between high compressive strength and low mass. The baseline penetrator design was evaluated and refined using the DYNA3D hydrocode to determine the survivability of the penetrator in sand at an impact velocity of 300m/s and an attack angle of 8 degrees. The simulations predicted that the penetrator design would survive this severe impact condition which was confirmed by experiments on the Pendine rocket test track.

  10. Cumulus-oocyte complexes from small antral follicles during the early follicular phase of menstrual cycles in rhesus monkeys yield oocytes that reinitiate meiosis and fertilize in vitro.

    PubMed

    Peluffo, Marina C; Barrett, Susan L; Stouffer, Richard L; Hennebold, Jon D; Zelinski, Mary B

    2010-10-01

    The stage at which follicle-enclosed cumulus-oocyte complexes achieve developmental competence in primates is unknown. Therefore, studies were designed to characterize the ability of oocytes in small antral follicles present during the menstrual cycle to spontaneously resume meiosis, fertilize, and support early embryo development. Ovaries were removed from adult rhesus monkeys (n = 12) during the early follicular phase (Days 3-4) of spontaneous cycles. Small antral follicles were divided into five groups according to their diameter; group I: <0.5 mm; group II: 0.5-0.99 mm; group III: 1.0-1.49 mm; group IV: 1.5-1.99 mm; and group V: 2.0-2.5 mm. The cumulus-oocyte complex from healthy small antral follicles (devoid of dark oocytes or granulosa cells) were extracted (n = 199) and cultured for 48 h under different conditions: in TALP (tyrode, albumin, lactate, pyruvate) medium alone, SAGE medium alone, or plus gonadotropins. At 48 h, oocyte meiotic status and diameter were measured after treatment of cumulus-oocyte complexes with hyaluronidase. Cumulus-oocyte complexes derived from follicles of 0.5- to 2-mm diameter contain oocytes that typically reinitiate meiosis in the absence or presence of gonadotropins and fertilize via in vitro fertilization or intracytoplasmic sperm injection. Moreover, the inseminated oocytes can reach the morula stage but arrest. Thus, the ability of these oocytes to complete maturation, as monitored from subsequent embryonic development after fertilization, is suboptimal. Further studies on primate IVM of oocytes from SAFs are warranted in order for them to be considered as an additional, novel source of gametes for fertility preservation in cancer patients. PMID:20519694

  11. Selection of developmentally competent buffalo oocytes by brilliant cresyl blue staining before IVM.

    PubMed

    Manjunatha, B M; Gupta, P S P; Devaraj, M; Ravindra, J P; Nandi, S

    2007-12-01

    The brilliant cresyl blue (BCB) test determines the activity of glucose-6-phosphate dehydrogenase (G6PDH); the activity of this enzyme is greatest in growing oocytes, but it declines as oocytes mature. The objective was to develop and evaluate this test for assessing development of buffalo oocytes (to select developmentally competent oocytes for increased in vitro embryo production). Oocytes were exposed to BCB stain diluted in mDPBS (DPBS with 0.4% BSA) for 90 min at 38.5 degrees C in a humidified air atmosphere; those with or without blue coloration of the cytoplasm were designated as BCB+ and BCB-, respectively. In Experiment 1, oocytes were exposed to 13, 26, or 39 microM BCB. There were fewer BCB+ oocytes after exposure to 13 microM BCB (10%) than after exposure to 26 or 39 microM BCB (57.2 and 61.8%; P<0.05), but there was no significant difference among treatments for blastocyst production rate. In Experiment 2, the diameter of BCB+ oocytes (144.4+/-4.2 microm; mean+/-S.E.M.) was higher (P<0.05) than that of BCB- oocytes (136.8+/-4.6 microm). In Experiment 3, oocytes were allocated into three groups: control (immediately cultured); holding-control (kept in mDPBS for 90 min before cultured); and treatment-incubation (incubated with 26 microM BCB). After IVM, oocytes were fertilized in vitro and cultured on an oviductal monolayer. The nuclear maturation rate was higher (P<0.05) in BCB+ (86.2%), control (83.4%) and holding-control (82.6%) oocytes than BCB- (59.2%) oocytes. The BCB+ oocytes yielded more blastocysts than control or holding-control oocytes (33.4, 20.2, and 21.0%, P<0.05); blastocyst development was lowest in BCB- oocytes (5.2%). In conclusion, staining of buffalo oocytes with BCB before IVM may be used to select developmentally competent oocytes for increased in vitro embryo production. PMID:17920672

  12. Oocyte biology and challenges in developing in vitro maturation systems in the domestic dog

    PubMed Central

    Songsasen, N.; Wildt, D.E.

    2007-01-01

    The oocyte of the domestic dog is unique from that of other mammalian species studied to date. Ovulation occurs either once or twice per year, with the oocyte released at the germinal vesicle stage and then completing nuclear and cytoplasmic maturation within the oviduct under the influence of rising circulating progesterone. In vivo meiotic maturation of the bitch oocyte is completed within 48 to 72 h after ovulation, which is longer than 12 to 36 h required for oocytes from most other mammalian species. Due to these inherently novel traits, in vitro culture systems developed for maturing oocytes of other species have been found inadequate for maturation of dog oocytes. On average, only 15 to 20% of ovarian oocytes achieve the metaphase II stage after 48 to 72 h of in vitro culture. Thus far, no offspring have been produced in the dog (or other canids) by transferring embryos derived from in vitro matured oocytes. This review addresses current knowledge about dog reproductive physiology, specifically those factors influencing in vitro developmental competence of the oocyte. This summary lays a foundation for identifying the next steps to understanding the mechanisms regulating meiotic maturation and developmental competence of the dog oocyte. PMID:17097840

  13. Metabolic control of oocyte development: linking maternal nutrition and reproductive outcomes

    PubMed Central

    Liu, Honglin; Gu, Xi; Boots, Christina; Moley, Kelle H.

    2015-01-01

    Obesity, diabetes, and related metabolic disorders are major health issues worldwide. As the epidemic of metabolic disorders continues, the associated medical comorbidities, including the detrimental impact on reproduction, increase as well. Emerging evidence suggests that the effects of maternal nutrition on reproductive outcomes are likely to be mediated, at least in part, by oocyte metabolism. Well-balanced and timed energy metabolism is critical for optimal development of oocytes. To date, much of our understanding of oocyte metabolism comes from the effects of extrinsic nutrients on oocyte maturation. In contrast, intrinsic regulation of oocyte development by metabolic enzymes, intracellular mediators, and transport systems is less characterized. Specifically, decreased acid transport proteins levels, increased glucose/lipid content and elevated reactive oxygen species in oocytes have been implicated in meiotic defects, organelle dysfunction and epigenetic alteration. Therefore, metabolic disturbances in oocytes may contribute to the diminished reproductive potential experienced by women with metabolic disorders. In-depth research is needed to further explore the underlying mechanisms. This review also discusses several approaches for metabolic analysis. Metabolomic profiling of oocytes, the surrounding granulosa cells, and follicular fluid will uncover the metabolic networks regulating oocyte development, potentially leading to the identification of oocyte quality markers and prevention of reproductive disease and poor outcomes in offspring. PMID:25280482

  14. Limestone, shale penetration rate equations developed

    Microsoft Academic Search

    M. E. Osman; S. A. Mohammed

    1992-01-01

    Increasing rotary speed has a greater effect on increasing rate of penetration in Abu Dhabi shales and limestones than other drilling parameters, including various mechanical and hydraulic factors. The graphical presentation of drilling parameters and penetration rate data found that rotary speed is the most important factor in controlling rate of penetration. Constants for the penetration rate equations were developed

  15. PENETRATION OF 5FLUOROURACIL IN EXCISED SKIN

    Microsoft Academic Search

    Jordan L. Cohen; Richard B. Stoughton

    1974-01-01

    Total penetration of 5-fluorouracil (FU) through human and hairless mouse skin was measured in vitro and the results were compared using radioactively labelled drug and a gas chromatographic method specific for the free FU molecule. Both methods were used to determine whether metabolism, either in the skin during penetration or in the penetration wells, could have affected the percent penetration

  16. Restoration of immune responses of aging hamsters by treatment with isoprinosine.

    PubMed Central

    Tsang, K Y; Fudenberg, H H; Gnagy, M J

    1983-01-01

    Immune competence declines with advanced age in hamsters, as in other laboratory mammals and in humans. We found significant alterations in the functional parameters of different populations of immunocytes (natural killer cells, T cells, monocytes, and suppressor cells) in aging hamsters, beginning at approximately 14 mo of age. Natural killer cytotoxicity, phytohemagglutinin-induced lymphocyte stimulation, and monocyte chemotaxis were decreased in aging Lak:LvG(Syr) outbred hamsters. When old hamsters were given a single injection (5 mg/kg body wt) of isoprinosine, a chemical immune potentiator, these three immune parameters increased almost to the levels found in young adult hamsters but returned to pretreatment levels after 7 d. Suppressor cell activity for the lymphocyte response to phytohemagglutinin, which increased with age, was decreased after treatment. In old hamsters treated with weekly injections of isoprinosine, these four immunological parameters remained at or near the levels found in young adults. PMID:6190840

  17. Oocyte-specific inactivation of Omcg1 leads to DNA damage and c-Abl/TAp63-dependent oocyte death associated with dramatic remodeling of ovarian somatic cells.

    PubMed

    Vandormael-Pournin, S; Guigon, C J; Ishaq, M; Coudouel, N; Avé, P; Huerre, M; Magre, S; Cohen-Tannoudji, J; Cohen-Tannoudji, M

    2015-01-01

    Aberrant loss of oocytes following cancer treatments or genetic mutations leads to premature ovarian insufficiency (POI) associated with endocrine-related disorders in 1% of women. Therefore, understanding the mechanisms governing oocyte death is crucial for the preservation of female fertility. Here, we report the striking reproductive features of a novel mouse model of POI obtained through oocyte-specific inactivation (ocKO) of Omcg1/Zfp830 encoding a nuclear zinc finger protein involved in pre-mRNA processing. Genetic ablation of OMCG1 in early growing oocytes leads to reduced transcription, accumulation of DNA double-strand breaks and subsequent c-Abl/TAp63-dependent oocyte death, thus uncovering the key role of OMCG1 for oocyte genomic integrity. All adult Omcg1(ocKO) females displayed complete elimination of early growing oocytes and sterility. Unexpectedly, mutant females exhibited a normal onset of puberty and sexual receptivity. Detailed studies of Omcg1(ocKO) ovaries revealed that the ovarian somatic compartment underwent a dramatic structural and functional remodeling. This allowed the cooperation between oocyte-depleted follicles and interstitial tissue to produce estradiol. Moreover, despite early folliculogenesis arrest, mutant mice exhibited sexual cyclicity as shown by cyclical changes in estrogen secretion, vaginal epithelium cytology and genital tract weight. Collectively, our findings demonstrate the key role of Omcg1 for oocyte survival and highlight the contribution of p63 pathway in damaged oocyte elimination in adulthood. Moreover, our findings challenge the prevailing view that sexual cyclicity is tightly dependent upon the pace of folliculogenesis and luteal differentiation. PMID:25168238

  18. A Role for Retrotransposon LINE-1 in Fetal Oocyte Attrition in Mice

    PubMed Central

    Malki, Safia; van der Heijden, Godfried W.; O'Donnell, Kathryn A.; Martin, Sandra L.; Bortvin, Alex

    2014-01-01

    SUMMARY Fetal oocyte attrition (FOA) is a conserved but poorly understood process of elimination of over two-thirds of meiotic prophase I (MPI) oocytes before birth. We now implicate retrotransposons LINE-1 (L1), activated during epigenetic reprogramming of the embryonic germline, in FOA in mice. We show that wild-type fetal oocytes possess differential nuclear levels of L1ORF1p, a L1-encoded protein essential for L1 ribonucleoprotein particle (L1RNP) formation and L1 retrotransposition. We demonstrate that experimental elevation of L1 expression correlates with increased MPI defects, FOA, oocyte aneuploidy and embryonic lethality. Conversely, reverse transcriptase (RT) inhibitor AZT has a profound effect on the FOA dynamics and meiotic recombination, and implicates an RT-dependent trigger in oocyte elimination in early MPI. We propose that FOA serves to select oocytes with limited L1 activity and therefore best suited for the next generation. PMID:24882376

  19. Developmental Control of Oocyte Maturation and Egg Activation in Metazoan Models

    PubMed Central

    Von Stetina, Jessica R.; Orr-Weaver, Terry L.

    2011-01-01

    Production of functional eggs requires meiosis to be coordinated with developmental signals. Oocytes arrest in prophase I to permit oocyte differentiation, and in most animals, a second meiotic arrest links completion of meiosis to fertilization. Comparison of oocyte maturation and egg activation between mammals, Caenorhabditis elegans, and Drosophila reveal conserved signaling pathways and regulatory mechanisms as well as unique adaptations for reproductive strategies. Recent studies in mammals and C. elegans show the role of signaling between surrounding somatic cells and the oocyte in maintaining the prophase I arrest and controlling maturation. Proteins that regulate levels of active Cdk1/cyclin B during prophase I arrest have been identified in Drosophila. Protein kinases play crucial roles in the transition from meiosis in the oocyte to mitotic embryonic divisions in C. elegans and Drosophila. Here we will contrast the regulation of key meiotic events in oocytes. PMID:21709181

  20. Simple, fast, and efficient method of manual oocyte enucleation using a pulled Pasteur pipette.

    PubMed

    Hosseini, S M; Moulavi, F; Asgari, V; Shirazi, A; Abazari-Kia, A H; Ghanaei, H R; Nasr-Esfahani, M H

    2013-09-01

    Cloning mammals by somatic cell nuclear transfer entails the replacement of oocyte chromosomes with the nucleus of a somatic cell. A major step in this technique is to efficiently produce large batches of enucleated oocytes, a process that requires considerable micromanipulation skills and expensive equipments. Here, a simple, fast, and efficient method of manual oocyte enucleation was introduced that can be adopted in every laboratory with the minimum equipments. Common laboratory glass pipettes were pulled on the flame of a burner and then used for manual bisection or enucleation of sheep and goat zona-free oocytes by passing them through the discontinuous cutting border of culture medium and mineral oil. The described techniques showed a certain efficiency to conveniently bisect or enucleate large batches of sheep, and goat oocytes being pre-treated with demecolcine. The method may be straightforward for simple manipulation of oocytes of other species and for development of automated cloning methods as well. PMID:23824953

  1. Pulmonary Responses to Amiodarone in Hamsters: Comparison of Intratracheal and Oral Administrations

    Microsoft Academic Search

    T. L. Blake; M. J. Reasor

    1995-01-01

    Amiodarone (AD) has been shown to produce a transient pulmonary fibrosis in hamsters after intratracheal (i.t.) instillation. The goal of this study was to examine bronchoalveolar lavage (BAL) parameters during the development of fibrosis after i.t. AD in hamsters and to examine the responses to oral AD in hamsters for comparison to responses to i.t. AD in an effort to

  2. Microsurgical Injection of Spermatozoa into Hamster Eggs with Subsequent Transformation of Sperm Nuclei into Male Pronuclei

    Microsoft Academic Search

    T. UEHARA; R. YANAGIMACHI

    1976-01-01

    Isolated nuclei of hamster spermatozoa develop into male pronuclei when injected into hamster eggs. The nuclei of fresh, frozen-thawed and freeze-dried human spermatozoa are equally capable of developing into male pronuclei when injected into hamster eggs. These results indicate that sperm nuclei are stable organdIes and the egg cytoplasmic factors controlling the transformation of sperm nuclei into male pronuclei are

  3. Dialysable leukocyte extracts modify the course of experimental paracoccidioidomycosis in the Syrian hamster

    Microsoft Academic Search

    M. T. S. Peraçoli; M. T. Rezkallah-Iwasso; N. G. S. Mota; M. R. Montenegro

    1993-01-01

    The effect of dialysable leukocyte extracts (DLE) obtained from hamsters immunized withParacoccidioides brasiliensis (immune DLE) and from non-immunized hamsters (non-immune DLE) was studied in hamsters inoculated withP. brasiliensis by the intratesticular route. Treatment with immune or non-immune DLE was started during the third week of infection and was repeated at 7, 11, 15 and 19 weeks. A group of untreated

  4. Phase response curve to anisomycin in tau mutant hamsters.

    PubMed

    Mrosovsky, N; Ralph, M R

    1992-09-15

    Administration of the protein synthesis inhibitor, anisomycin, to wild type hamsters produces phase shifts in their circadian rhythms that have similarities to shifts produced by non-photic behavioral stimulation. A mutation that shortens the period of rhythms in hamsters results in altered responsiveness to non-photic input. However, responses of the mutants to anisomycin are unaffected: their phase response curve (PRC) for anisomycin is similar to that of wild types. This suggests that 1) anisomycin is not acting on mechanisms specifically involved in non-photic behavioral phase shifting, and 2) the mutation affects the non-photic input pathway or the pacemaker itself at a point that is upstream from anisomycin's site of action. PMID:1397185

  5. Autoradiography in fetal golden hamsters treated with tritiated diethylnitrosamine

    SciTech Connect

    Reznik-Schueller, H.M.; Hague, B.F. Jr.

    1981-04-01

    Tritiated diethylnitrosamine was administered to female Syrian golden hamsters on each of the last 4 days (days 12-15) of pregnancy. The distribution of bound radioactivity was monitored by light microscopic autoradiography of fetal tracheas and livers, the placentas, and the maternal livers. In the trachea, the fetal target organ, bound radioactivity was restricted to the respiratory epithelium, where diethylnitrosamine-induced tracheal tumors arise. Mucous cells and nonciliated stem cells were identified as the principal sites of binding; other cell types within the tracheal epithelium contained only small amounts of bound radioactivity. The level of binding observed in the fetal trachea increased steadily from day 12 to day 15, which correlated well with the levels of differentiation of this tissue during this period. This observation also agrees with the previously reported observation that tumor incidence increases from 40 to 95% in Syrian golden hamsters between days 12 and 15.

  6. Sarcolemmal phospholipid N-methylation in genetically determined hamster cardiomyopathy

    SciTech Connect

    Okumura, K.; Panagia, V.; Jasmin, G.; Dhalla, N.S.

    1987-02-27

    The heart sarcolemmal phosphatidylethanolamine N-methylation in UM-X7.1 strain of cardiomyopathic hamsters was examined by using 0.055, 10 and 150 microM S-adenosyl-L-(methyl-/sup 3/H) methionine as methyl donor for sites I, II and III, respectively. In comparison with control values, methylation activities at site I was increased in 40, 120 and 250 days old cardiomyopathic hamsters. On the other hand, methylation activities at sites II and III in 120 and 250 days old cardiomyopathic animals were depressed without any change in the 40 days old group. The alterations in N-methylation activities were associated with kinetic changes in apparent Vmax values without any changes in the apparent Km. These results indicate a defect in the phospholipid N-methylation process in heart sarcolemma during the development of genetically determined cardiomyopathy.

  7. [Legislative and regulatory situation of oocytes donation in France].

    PubMed

    Letur, H; Merlet, F

    2012-08-01

    In France, medically assisted procreation (MAP) activities and gamete donation are strictly regulated by the bioethics law. The main ethical principles applied to the donation--no remuneration, anonymity, and the requirement for free and informed consent--aim to protect donors. In the same spirit, since MAP with oocytes donation is recognized as a healthcare activity, receiving couples benefit from exemption from co-payments by the health insurance system. Thus, it is widely accessible to couples presenting medical infertility requiring oocytes from a donor, but availability is insufficient to cover needs. This shortage in supply results in moving the demand abroad where this particular MAP is exercised at varying levels of supervision. PMID:23141596

  8. Receptor-mediated Endocytosis in the Caenorhabditis elegans Oocyte

    PubMed Central

    Grant, Barth; Hirsh, David

    1999-01-01

    The Caenorhabditis elegans oocyte is a highly amenable system for forward and reverse genetic analysis of receptor-mediated endocytosis. We describe the use of transgenic strains expressing a vitellogenin::green fluorescent protein (YP170::GFP) fusion to monitor yolk endocytosis by the C. elegans oocyte in vivo. This YP170::GFP reporter was used to assay the functions of C. elegans predicted proteins homologous to vertebrate endocytosis factors using RNA-mediated interference. We show that the basic components and pathways of endocytic trafficking are conserved between C. elegans and vertebrates, and that this system can be used to test the endocytic functions of any new gene. We also used the YP170::GFP assay to identify rme (receptor-mediated endocytosis) mutants. We describe a new member of the low-density lipoprotein receptor superfamily, RME-2, identified in our screens for endocytosis defective mutants. We show that RME-2 is the C. elegans yolk receptor. PMID:10588660

  9. Expression of catfish amino acid taste receptors in Xenopus oocytes.

    PubMed

    Getchell, T V; Grillo, M; Tate, S S; Urade, R; Teeter, J; Margolis, F L

    1990-04-01

    We demonstrate that poly (A+)RNA isolated from catfish barbels directs the expression of functional amino acid taste receptors in the Xenopus oocyte. The activity of these receptors is monitored in ovo by the two electrode voltage clamp technique. Specific conductance changes recorded in response to amino acid stimulation are analogous to those recorded electrophysiologically from intact catfish barbels. These responses exhibit specificity, reproducibility, rapid onset and termination, and desensitization to repetitive stimulation. A functional assay system that encompasses the full complement of transduction events from the ligand-receptor interaction to subsequent conductance changes is necessary to identify molecular components responsible for these events. Our results demonstrate that the Xenopus oocyte can be used to characterize and identify clones coding for amino acid taste receptors analogous to its use in studying receptor molecules for other neuroactive compounds. PMID:1697041

  10. Electrical currents through full-grown and maturing Xenopus oocytes.

    PubMed Central

    Robinson, K R

    1979-01-01

    An extracellular vibrating electrode was used to map the current pattern around Xenopus laevis oocytes. Current was found to enter the animal hemisphere and leave the vegetal hemisphere; in fully grown oocytes from which the follicle cells had been removed, the maximal current density was about 1 microamperemeter/cm2. This current decreased to nearly zero in response to progesterone and several other maturation-producing agents. In the case of progesterone, the decline began within a few minutes of the addition of the hormone and proceeded with a half-time of about 20 min. An analysis of the effects on the current of the removal or addition of various ions and drugs led to the inference that the major current-carrying ion was chloride and that the chloride permeability was controlled by calcium. PMID:284407

  11. Transplantation of hamster xenogeneic tissue in syngeneic murine chimaeras

    Microsoft Academic Search

    J. B. Bridges; Janet K. Houston

    1975-01-01

    Summary  CBA mice exposed to an otherwise lethal dose of irradiation (1006 rads) were saved by the intravenous injection of suspensions\\u000a of CBA bone marrow cells. Hamster kidney cells (BHK) were injected intraperitoneally into these mice at 1, 3, 7 and 14 days\\u000a after irradiation and marrow injection. The injected cells survived and proliferated in the abdominal cavities of the mice.

  12. Expression of human angiogenin in cultured baby hamster kidney cells

    SciTech Connect

    Kurachi, K.; Rybak, S.M.; Fett, J.W.; Shapiro, R.; Strydom, D.J.; Olson, K.A.; Riordan, J.F.; Davie, E.W.; Vallee, B.L.

    1988-08-23

    Baby hamster kidney cells were transformed with DNA sequences derived from the gene for human angiogenin. Expression was under the transcriptional control of the inducible mouse metallothionein 1 promoter. Recombinant angiogenin was purified and shown to be chemically, biologically, and enzymatically indistinguishable from the natural product. The large-scale production of recombinant angiogenin achieved should facilitate detailed studies into the structure-function relationships of this potent angiogenic molecule.

  13. Circadian arrhythmia dysregulates emotional behaviors in aged Siberian hamsters

    PubMed Central

    Prendergast, Brian J.; Onishi, Kenneth G.; Patel, Priyesh N.; Stevenson, Tyler J.

    2014-01-01

    Emotional behaviors are influenced by the circadian timing system. Circadian disruptions are associated with depressive-like symptoms in clinical and preclinical populations. Circadian rhythm robustness declines markedly with aging and may contribute to susceptibility to emotional dysregulation in aged individuals. The present experiments used a model of chronic circadian arrhythmia generated noninvasively, via a series of circadian-disruptive light treatments, to investigate interactions between circadian desynchrony and aging on depressive- and anxiety-like behaviors, and on limbic neuroinflammatory gene expression that has been linked with emotionality. We also examined whether a social manipulation (group housing) would attenuate effects of arrhythmia on emotionality. In aged (14-18 months of age) male Siberian hamsters, circadian arrhythmia increased behavioral despair and decreased social motivation, but decreased exploratory anxiety. These effects were not evident in younger (5-9 months of age) hamsters. Social housing (3-5 hamsters/cage) abolished the effects of circadian arrhythmia on emotionality. Circadian arrhythmia alone was without effect on hippocampal or cortical interleukin-1? (IL-1?) and indoleamine 2,3-dioxygenase (Ido) mRNA expression in aged hamsters, but social housing decreased hippocampal IL-1? and Ido mRNAs. The data demonstrate that circadian disruption can negatively impact affective state, and that this effect is pronounced in older individuals. Although clear associations between circadian arrhythmia and constitutive limbic proinflammatory activity were not evident, the present data suggest that social housing markedly inhibits constitutive hippocampal IL-1? and Ido activity, which may contribute to the ameliorating effects of social housing on a number of emotional behaviors. PMID:24333374

  14. Multiple Requirements of PLK1 during Mouse Oocyte Maturation

    PubMed Central

    Solc, Petr; Kitajima, Tomoya S.; Yoshida, Shuhei; Brzakova, Adela; Kaido, Masako; Baran, Vladimir; Mayer, Alexandra; Samalova, Pavlina; Motlik, Jan; Ellenberg, Jan

    2015-01-01

    Polo-like kinase 1 (PLK1) orchestrates multiple events of cell division. Although PLK1 function has been intensively studied in centriole-containing and rapidly cycling somatic cells, much less is known about its function in the meiotic divisions of mammalian oocytes, which arrest for a long period of time in prophase before meiotic resumption and lack centrioles for spindle assembly. Here, using specific small molecule inhibition combined with live mouse oocyte imaging, we comprehensively characterize meiotic PLK1’s functions. We show that PLK1 becomes activated at meiotic resumption on microtubule organizing centers (MTOCs) and later at kinetochores. PLK1 is required for efficient meiotic resumption by promoting nuclear envelope breakdown. PLK1 is also needed to recruit centrosomal proteins to acentriolar MTOCs to promote normal spindle formation, as well as for stable kinetochore-microtubule attachment. Consequently, PLK1 inhibition leads to metaphase I arrest with misaligned chromosomes activating the spindle assembly checkpoint (SAC). Unlike in mitosis, the metaphase I arrest is not bypassed by the inactivation of the SAC. We show that PLK1 is required for the full activation of the anaphase promoting complex/cyclosome (APC/C) by promoting the degradation of the APC/C inhibitor EMI1 and is therefore essential for entry into anaphase I. Moreover, our data suggest that PLK1 is required for proper chromosome segregation and the maintenance of chromosome condensation during the meiosis I-II transition, independently of the APC/C. Thus, our results define the meiotic roles of PLK1 in oocytes and reveal interesting differential requirements of PLK1 between mitosis and oocyte meiosis in mammals. PMID:25658810

  15. Chemical structure of sterols that activate oocyte meiosis

    Microsoft Academic Search

    Anne Grete Byskov; Claus Yding Andersen; Lars Nordholm; Henning Thogersen; Xia Guoliang; Ole Wassmann; Jan Vanggaard Andersen; Erling Guddal; Tiny Roed

    1995-01-01

    GONADOTROPHINS and various growth factors, but not sex steroids, can induce resumption of meiosis in vitro, but only in oocytes enclosed by cumulus-granulosa cells1. Follicular purines prevent resumption of meiosis2,3. This process can be overcome, in vitro, by a transient elevation of cyclic AMP resulting in the production of a diffusible meiosis-inducing substance secreted by the cumulus cells4. A meiosis-inducing

  16. Time course of meiotic spindle development in MII oocytes.

    PubMed

    Kilani, Suha; Cooke, Simon; Chapman, Michael

    2011-02-01

    The aim of this study was to examine changes in meiotic spindle morphology over time to potentially optimize timing for ICSI. Using polarized light microscopy, images of MII oocytes were captured after retrieval of oocytes in stimulated cycles at six time intervals in culture: 36-36.5 h, 36.5-37.0 h, 38-38.5 h, 39-39.5 h, 40-40.5 h and 40.5-41 h post hCG. Captured images were analysed for spindle presence and their retardance. Results showed that spindles were detected in 58% (45/78) of oocytes at 36-36.5 h. This percentage rose to a peak (96% vs. 58%, p < 0.001) at 39-39.5 h and stabilized between 39-40.5 h post trigger then significantly declined at 40.5-41 h post hCG (96% vs. 77%, p < 0.001). Average spindle retardance increased from 36-36.5 h (1.8 ± 0.7 nm) until it peaked at 39-40.5 h (3.8 ± 0.8 nm, p < 0.0001) and then declined significantly after 40.5-41 h (3.2 ± 0.9 nm, p = 0.0001). These results show that the meiotic spindle appearance is time dependent with the majority of oocytes having detectable spindles and highest retardance between 39-40.5 h post hCG under currently used stimulation protocol after which they start to disaggregate. 39-40.5 h post hCG may be the optimal time for ICSI. PMID:20569507

  17. Introduction: nongenetic markers of oocyte and embryo competence.

    PubMed

    Meldrum, David R

    2015-02-01

    The authors of this Views and Reviews have outlined the complexities of oocyte and embryo development and candidates for markers of embryo competence. Time-lapse monitoring of embryo development allows hierarchical selection of embryos for day 3 transfer. However, for normal-prognosis patients, extended embryo culture and comprehensive chromosome screening currently stand as the ultimate tools for the selection of embryos capable of a viable, normal delivery. PMID:25639966

  18. Host cell factors controlling vimentin organization in the Xenopus oocyte

    PubMed Central

    1992-01-01

    To study vimentin filament organization in vivo we injected Xenopus oocytes, which have no significant vimentin system of their own, with in vitro-synthesized RNAs encoding Xenopus vimentins. Exogenous vimentins were localized primarily to the cytoplasmic surface of the nucleus and to the subplasma membrane "cortex." In the cortex of the animal hemisphere, wild-type vimentin forms punctate structures and short filaments. In contrast, long anastomosing vimentin filaments are formed in the vegetal hemisphere cortex. This asymmetry in the organization of exogenous vimentin is similar to that of the endogenous keratin system (Klymkowsky, M. W., L. A. Maynell, and A. G. Polson. 1987. Development (Camb.). 100:543-557), which suggests that the same cellular factors are responsible for both. Before germinal vesicle breakdown, in the initial stage of oocyte maturation, large vimentin and keratin filament bundles appear in the animal hemisphere. As maturation proceeds, keratin filaments fragment into soluble oligomers (Klymkowsky, M. W., L. A. Maynell, and C. Nislow. 1991. J. Cell Biol. 114:787-797), while vimentin filaments remain intact and vimentin is hyperphosphorylated. To examine the role of MPF kinase in the M-phase reorganization of vimentin we deleted the conserved proline of vimentin's single MPF-kinase site; this mutation had no apparent effect on the prophase or M-phase behavior of vimentin. In contrast, deletion of amino acids 19-68 or 18-61 of the NH2-terminal "head" domain produced proteins that formed extended filaments in the animal hemisphere of the prophase oocyte. We suggest that the animal hemisphere cortex of the prophase oocyte contains a factor that actively suppresses the formation of extended vimentin filaments through a direct interaction with vimentin's head domain. During maturation this "suppressor of extended filaments" appears to be inactivated, leading to the formation of an extended vimentin filament system. PMID:1429840

  19. Fertilization and development of Caprine oocytes matured over granulosa cell monolayers

    Microsoft Academic Search

    Alok Teotia; G. Taru Sharma; A. C Majumdar

    2001-01-01

    The aim of the present study was to compare the two oocyte maturation systems, i.e. a granulosa cell (GC) monolayer from small (<4mm) or large (>4mm) follicles and a granulosa co-culture for their effects on in vitro maturation (IVM), fertilization and developmental competence of caprine oocytes. A total of 1945 oocytes were used for studies on maturation, fertilization and embryo

  20. MicroRNA-378 regulates oocyte maturation via the suppression of aromatase in porcine cumulus cells.

    PubMed

    Pan, Bo; Toms, Derek; Shen, Wei; Li, Julang

    2015-03-15

    We sought to investigate whether miR-378 plays a role in cumulus cells and whether the manipulation of miRNA levels in cumulus cells influences oocyte maturation in vitro. Cumulus-oocyte complexes (COCs) from ovarian follicles had significantly lower levels of precursor and mature miR-378 in cumulus cells surrounding metaphase II (MII) oocytes than cumulus cells surrounding germinal vesicle (GV) oocytes, suggesting a possible role of miR-378 during COC maturation. Overexpression of miR-378 in cumulus cells impaired expansion and decreased expression of genes associated with expansion (HAS2, PTGS2) and oocyte maturation (CX43, ADAMTS1, PGR). Cumulus cell expression of miR-378 also suppressed oocyte progression from the GV to MII stage (from 54 ± 2.7 to 31 ± 5.1%), accompanied by a decrease of growth differentiation factor 9 (GDF9), bone morphogenetic protein 15 (BMP15), zona pellucida 3 (ZP3), and CX37 in the oocytes. Subsequent in vitro fertilization resulted in fewer oocytes from COCs overexpressing miR-378 reaching the blastocyst stage (7.3 ± 0.7 vs. 16.6 ± 0.5%). miR-378 knockdown led to increased cumulus expansion and oocyte progression to MII, confirming a specific effect of miR-378 in suppressing COC maturation. Aromatase (CYP19A1) expression in cumulus cells was also inhibited by miR-378, leading to a significant decrease in estradiol production. The addition of estradiol to IVM culture medium reversed the effect of miR-378 on cumulus expansion and oocyte meiotic progression, suggesting that decreased estradiol production via suppression of aromatase may be one of the mechanisms by which miR-378 regulates the maturation of COCs. Our data suggest that miR-378 alters gene expression and function in cumulus cells and influences oocyte maturation, possibly via oocyte-cumulus interaction and paracrine regulation. PMID:25628423

  1. Functional and Molecular Reorganization of the Nucleolar Apparatus in Maturing Mouse Oocytes

    Microsoft Academic Search

    Olga V. Zatsepina; Christine Bouniol-Baly; Claudine Amirand; Pascale Debey

    2000-01-01

    In mammalian preovulatory oocytes, rRNA synthesis is down-regulated until egg fertilization and zygotic genome reactivation, but the underlying regulatory mechanisms of this phenomenon are poorly characterized. We examined the molecular organization of the rRNA synthesis and processing machineries in fully grown mouse oocytes in relation to ongoing rDNA transcription and oocyte progression throughout meiosis. We show that, at the germinal

  2. ?-endosulfine (ENSA) regulates exit from prophase I arrest in mouse oocytes

    PubMed Central

    Matthews, Lauren M; Evans, Janice P

    2014-01-01

    Mammalian oocytes in ovarian follicles are arrested in meiosis at prophase I. This arrest is maintained until ovulation, upon which the oocyte exits from this arrest, progresses through meiosis I and to metaphase of meiosis II. The progression from prophase I to metaphase II, known as meiotic maturation, is mediated by signals that coordinate these transitions in the life of the oocyte. ENSA (?-endosulfine) and ARPP19 (cAMP-regulated phosphoprotein-19) have emerged as regulators of M-phase, with function in inhibition of protein phosphatase 2A (PP2A) activity. Inhibition of PP2A maintains the phosphorylated state of CDK1 substrates, thus allowing progression into and/or maintenance of an M-phase state. We show here ENSA in mouse oocytes plays a key role in the progression from prophase I arrest into M-phase of meiosis I. The majority of ENSA-deficient oocytes fail to exit from prophase I arrest. This function of ENSA in oocytes is dependent on PP2A, and specifically on the regulatory subunit PPP2R2D (also known as B55?). Treatment of ENSA-deficient oocytes with Okadaic acid to inhibit PP2A rescues the defect in meiotic progression, with Okadaic acid-treated, ENSA-deficient oocytes being able to exit from prophase I arrest. Similarly, oocytes deficient in both ENSA and PPP2R2D are able to exit from prophase I arrest to an extent similar to wild-type oocytes. These data are evidence of a role for ENSA in regulating meiotic maturation in mammalian oocytes, and also have potential relevance to human oocyte biology, as mouse and human have genes encoding both Arpp19 and Ensa. PMID:24675883

  3. Exposure to a Physiologically Relevant Elevated Temperature Hastens In Vitro Maturation in Bovine Oocytes

    Microsoft Academic Search

    J. L. Edwards; A. M. Saxton; J. L. Lawrence; R. R. Payton; J. R. Dunlap

    2005-01-01

    The objective of this study was to evaluate nuclear (progression to metaphase II) and cytoplasmic (translo- cation of cortical granules to the oolemma) maturation in control (38.5°C) and heat-stressed (41.0°C) oocytes. Hoechst staining indicated that a similar proportion of control and heat-stressed oocytes progressed to meta- phase II. More heat-stressed oocytes had type III corti- cal granule distribution suggesting that

  4. Isolation of two chloroethylnitrosourea-sensitive Chinese hamster cell lines

    SciTech Connect

    Hata, H.; Numata, M.; Tohda, H.; Yasui, A.; Oikawa, A. (Tohoku Univ., Sendai (Japan))

    1991-01-01

    1-((4-Amino-2-methylpyrimidin-5-yl)methyl)-3-(2-chloroethyl)-3- nitrosourea hydrochloride (ACNU), a cancer chemotherapeutic bifunctional alkylating agent, causes chloroethylation of DNA and subsequent DNA strand cross-linking through an ethylene bridge. We isolated and characterized two ACNU-sensitive mutants from mutagenized Chinese hamster ovary cells and found them to be new drug-sensitive recessive Chinese hamster mutants. Both mutants were sensitive to various monofunctional alkylating agents in a way similar to that of the parental cell lines CHO9. One mutant (UVS1) was cross-sensitive to UV and complemented the UV sensitivity of all Chinese hamster cell lines of 7 established complementation groups. Since UV-induced unscheduled DNA synthesis was very low, a new locus related to excision repair is thought to be defective in this cell line. Another ACNU-sensitive mutant, CNU1, was slightly more sensitive to UV than the parent cell line. CNU1 was cross-sensitive to 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea and slightly more sensitive to mitomycin C. No increased accumulation of ACNU and a low level of UV-induced unscheduled DNA synthesis in this cell as compared with the parental cell line suggest that there is abnormality in a repair response of this mutant cell to some types of DNA cross-links.

  5. Histogenesis of pancreatic carcinogenesis in the hamster: ultrastructural evidence

    SciTech Connect

    Flaks, B.

    1984-06-01

    Pancreatic carcinogenesis in the Syrian hamster, induced by ..beta..-oxidized derivatives of N-nitroso-di-n-propylamine, constitutes a valuable model of human cancer of the exocrine pancreas. In both species the majority of tumors are adenocarcinomas: superficially, on the basis of their histological appearance, these appear to be ductal in origin. However, sequential analysis, by electron microscopy, of the development of pancreatic neoplasia in the hamster model indicates that acinar cells may participate in the histogenesis of ductal adenomas and carcinomas. Acinar cells appear to undergo changes in differentiation, including pseudoductular transformation, giving rise to a new population of cells that resemble ductular or centroacinar types. This new population may then proliferate to form, first, cystic foci and subsequently cytadenomas and adenocarcinomas. Mucous metaplasia appears to develop at late stages of tumor development. Although the participation of ductular and centroacinar cells in pancreatic carcinogenesis cannot be excluded, very few tumors arise from the ductal epithelium. It is possible that some human pancreatic adenocarcinomas may also have their origin from dysplastic acinar cells, by analogy with the hamster model: focal acinar dyplasia being common in human pancreatic cancer patients. 90 references, 18 figures.

  6. Teratogenicity and embryotoxicity of nickel carbonyl in Syrian hamsters

    SciTech Connect

    Sunderman, F.W. Jr.; Shen, S.K.; Reid, M.C.; Allpass, P.R.

    1980-01-01

    Nickel carbonyl was administered to groups of pregnant hamsters by inhalation on days 4, 5, 6, 7, or 8 of gestation. The dams were killed on day 15 of gestation, and the fetuses were examined for malformations. Exposure to Ni(CO)/sub 4/ on days 4 or 5 of gestation resulted in malformation in 5.5% and 5.8% of the progeny, respectively. Progeny included 9 fetuses with cystic lungs, 7 fetuses with exencephaly, 1 fetus with exencephaly plus fused rib and 1 fetus with anophthalmia plus cleft palate. Hemorrhages into serious cavities were found. In progeny of dams exposed to Ni(CO)/sub 4/ on days 6 or 7 of gestation, there was 1 fetus with fused ribs and there were 2 fetuses with hydronephrosis. In another experiment, pregnant hamsters were exposed to inhalation of Ni(CO)/sub 4/ on day 5 of gestation; these dams were permitted to deliver their litters and to nurse their pups. There was no significant difference in the average number of live pups in the Ni(CO)/sub 4/-exposed litters compared to control litters. Neonatal mortality was increased in Ni(CO)/sub 4/-exposed litters. This study demonstrates that Ni(CO)/sub 4/ is teratogenic and embryotoxic in Syrian hamsters.

  7. Ovarian germline stem cells: an unlimited source of oocytes?

    PubMed

    Hanna, Carol B; Hennebold, Jon D

    2014-01-01

    While there has been progress in directing the development of embryonic stem cells and induced pluripotent stem cells toward a germ cell state, their ability to serve as a source of functional oocytes in a clinically relevant model or situation has yet to be established. Recent studies suggest that the adult mammalian ovary is not endowed with a finite number of oocytes, but instead possesses stem cells that contribute to their renewal. The ability to isolate and promote the growth and development of such ovarian germline stem cells (GSCs) would provide a novel means to treat infertility in women. Although such ovarian GSCs are well characterized in nonmammalian model organisms, the findings that support the existence of adult ovarian GSCs in mammals have been met with considerable evidence that disputes their existence. This review details the lessons provided by model organisms that successfully utilize ovarian GSCs to allow for a continual and high level of female germ cell production throughout their life, with a specific focus on the cellular mechanisms involved in GSC self-renewal and oocyte development. Such an overview of the role that oogonial stem cells play in maintaining fertility in nonmammalian species serves as a backdrop for the data generated to date that supports or disputes the existence of GSCs in mammals as well as the future of this area of research in terms of its potential for any application in reproductive medicine. PMID:24382341

  8. Telomere lengths in human oocytes, cleavage stage embryos and blastocysts

    PubMed Central

    Turner, S.; Wong, H.P.; Rai, J.; Hartshorne, G.M.

    2010-01-01

    Telomeres are repeated sequences that protect the ends of chromosomes and harbour DNA repair proteins. Telomeres shorten during each cell division in the absence of telomerase. When telomere length becomes critically short, cell senescence occurs. Telomere length therefore reflects both cellular ageing and capacity for division. We have measured telomere length in human germinal vesicle (GV) oocytes and preimplantation embryos, by quantitative fluorescence in situ hybridization (Q-FISH), providing baseline data towards our hypothesis that telomere length is a marker of embryo quality. The numbers of fluorescent foci suggest that extensive clustering of telomeres occurs in mature GV stage oocytes, and in preimplantation embryos. When calculating average telomere length by assuming that each signal presents one telomere, the calculated telomere length decreased from the oocyte to the cleavage stages, and increased between the cleavage stages and the blastocyst (11.12 versus 8.43 versus 12.22 kb, respectively, P < 0.001). Other methods of calculation, based upon expected maximum and minimum numbers of telomeres, confirm that telomere length in blastocysts is significantly longer than cleavage stages. Individual blastomeres within an embryo showed substantial variation in calculated average telomere length. This study implies that telomere length changes according to the stage of preimplantation embryo development. PMID:20573647

  9. Pharmaceutical Options for Triggering of Final Oocyte Maturation in ART

    PubMed Central

    Humaidan, Peter; Bernabéu, Rafael

    2014-01-01

    Since the pioneering days of in vitro fertilization, hCG has been the gold standard to induce final follicular maturation. We herein reviewed different pharmaceutical options for triggering of final oocyte maturation in ART. The new upcoming agent seems to be GnRHa with its potential advantages over hCG trigger. GnRHa triggering elicits a surge of gonadotropins resembling the natural midcycle surge of gonadotropins, without the prolonged action of hCG, resulting in the retrieval of more mature oocytes and a significant reduction in or elimination of OHSS as compared to hCG triggering. The induction of final follicular maturation using GnRHa represents a paradigm shift in the ovulation triggering concept in ART and, thus, a way to develop a safer IVF procedure. Kisspeptins are key central regulators of the neuroendocrine mechanisms of human reproduction, who have been shown to effectively elicit an LH surge and to induce final oocyte maturation in IVF cycles. This new trigger concept may, therefore, offer a completely new, “natural” pharmacological option for ovulation induction. Whether kisspeptins will be the future agent to trigger ovulation remains to be further explored. PMID:25133168

  10. Ca(2+)(cyt) negatively regulates the initiation of oocyte maturation.

    PubMed

    Sun, Lu; Machaca, Khaled

    2004-04-01

    Ca(2+) is a ubiquitous intracellular messenger that is important for cell cycle progression. Genetic and biochemical evidence support a role for Ca(2+) in mitosis. In contrast, there has been a long-standing debate as to whether Ca(2+) signals are required for oocyte meiosis. Here, we show that cytoplasmic Ca(2+) (Ca(2+)(cyt)) plays a dual role during Xenopus oocyte maturation. Ca(2+) signals are dispensable for meiosis entry (germinal vesicle breakdown and chromosome condensation), but are required for the completion of meiosis I. Interestingly, in the absence of Ca(2+)(cyt) signals oocytes enter meiosis more rapidly due to faster activation of the MAPK-maturation promoting factor (MPF) kinase cascade. This Ca(2+)-dependent negative regulation of the cell cycle machinery (MAPK-MPF cascade) is due to Ca(2+)(cyt) acting downstream of protein kinase A but upstream of Mos (a MAPK kinase kinase). Therefore, high Ca(2+)(cyt) delays meiosis entry by negatively regulating the initiation of the MAPK-MPF cascade. These results show that Ca(2+) modulates both the cell cycle machinery and nuclear maturation during meiosis. PMID:15067021

  11. Dysferlin is essential for endocytosis in the sea star oocyte

    PubMed Central

    Oulhen, Nathalie; Onorato, Thomas M.; Ramos, Isabela; Wessel, Gary M.

    2014-01-01

    Dysferlin is a calcium-binding transmembrane protein involved in membrane fusion and membrane repair. In humans, mutations in the dysferlin gene are associated with muscular dystrophy. In this study, we isolated plasma membrane-enriched fractions from full-grown immature oocytes of the sea star, and identified dysferlin by mass spectrometry analysis. The full-length dysferlin sequence is highly conserved between human and the sea star. We learned that in the sea star Patiria miniata, dysferlin RNA and protein are expressed from oogenesis to gastrulation. Interestingly, the protein is highly enriched in the plasma membrane of oocytes. Injection of a morpholino against dysferlin leads to a decrease of endocytosis in oocytes, and to a developmental arrest during gastrulation. These results suggest that dysferlin is critical for normal endocytosis during oogenesis and for embryogenesis in the sea star and that this animal may be a useful model for studying the relationship of dysferlin structure as it relates to its function. PMID:24368072

  12. Rearranged mitochondrial genomes are present in human oocytes

    SciTech Connect

    Xi, Chen; Prosser, R.; Simonetti, S. [Columbia Univ., New York, NY (United States)] [and others

    1995-08-01

    Using quantitative PCR, we have determined that a human oocyte contains {approximately}100,000 mitochondrial genomes (mtDNAs). We have also found that some oocytes harbor measurable levels (up to 0.1%) of the so-called common deletion, an mtDNA molecule containing a 4,977-bp rearrangement that is present in high amounts in many patients with {open_quotes}sporadic{close_quotes} Kearns-Sayre syndrome (KSS) and progressive external ophthalmoplegia (PEO). This is the first demonstration that rearranged mtDNAs are present in human oocytes, and it provides experimental support for the supposition that pathogenic deletions associated with the ontogeny of sporadic KSS and PEO can be transmitted in the female germ line, from mother to child. The relevance of these findings to the accumulation of extremely low levels of deleted mtDNAs in both somatic and germ-line tissues during normal human aging is also discussed. 42 refs., 6 figs., 1 tab.

  13. Supplementation of canine oocyte in vitro maturation medium with progesterone, somatotropin, and epidermal growth factor

    E-print Network

    Willingham-Rocky, Lauri Ann

    2001-01-01

    mammalian species such as bovine, mouse, and human (Tesoriero et al. , 1981; Szabo, 1967). The size of canine oocytes as reported by Farstad at initial collection from the ovary, ranges from 70 pm to 130 pm, averaging 112 pm (without zona pellucida... or cumulus), while a mature oocyte with zona pellucida and cumulus cells produced in vivo is about 230-240 pm in diameter (Hoist and Phemister, 1971). Studies on oocyte size and competency have reported that canine oocytes greater than 110 pm have...

  14. Expression of functional neurotransmitter receptors in Xenopus oocytes after injection of human brain membranes

    NASA Astrophysics Data System (ADS)

    Miledi, Ricardo; Eusebi, Fabrizio; Martínez-Torres, Ataúlfo; Palma, Eleonora; Trettel, Flavia

    2002-10-01

    The Xenopus oocyte is a very powerful tool for studies of the structure and function of membrane proteins, e.g., messenger RNA extracted from the brain and injected into oocytes leads to the synthesis and membrane incorporation of many types of functional receptors and ion channels, and membrane vesicles from Torpedo electroplaques injected into oocytes fuse with the oocyte membrane and cause the appearance of functional Torpedo acetylcholine receptors and Cl channels. This approach was developed further to transplant already assembled neurotransmitter receptors from human brain cells to the plasma membrane of Xenopus oocytes. Membranes isolated from the temporal neocortex of a patient, operated for intractable epilepsy, were injected into oocytes and, within a few hours, the oocyte membrane acquired functional neurotransmitter receptors to -aminobutyric acid, -amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, kainate, and glycine. These receptors were also expressed in the plasma membrane of oocytes injected with mRNA extracted from the temporal neocortex of the same patient. All of this makes the Xenopus oocyte a more useful model than it already is for studies of the structure and function of many human membrane proteins and opens the way to novel pathophysiological investigations of some human brain disorders.

  15. Influence of the pseudophyllidean cestode Schistocephalus solidus on oocyte development in the threespine stickleback Gasterosteus aculeatus.

    PubMed

    Heins, D C; Brown-Peterson, N J

    2010-06-01

    The objective of this study was to investigate the means by which Schistocephalus solidus might reduce annual fecundity in female threespine stickleback fish (Gasterosteus aculeatus) through processes of oocyte development. Histological examinations of specimens from one lake in Alaska in 2000 and 2001 were used to analyse the effects of S. solidus on recruitment of primary growth oocytes into vitellogenesis, atresia of vitellogenic oocytes, and the interspawning interval. The ratio of primary growth to late secondary growth (late vitellogenic) oocytes was significantly greater (P<0.01) among infected fish than uninfected ones in early-season samples from 2000 and 2001, revealing a decrease in recruitment of oocytes from primary growth into vitellogenic oocytes among infected females. The difference was marginally non-significant (P=0.087) in a mid-season sample from 2001 due to reductions in the entire pool of vitellogenic (early and late secondary growth) oocytes recruited prior to the spawning season in this determinate-fecundity species. Atresia among all vitellogenic oocytes was low and did not differ between infected and uninfected females. Histological estimations of the interspawning interval using post-ovulatory follicles showed no significant differences between infected and uninfected fish, suggesting that the number of spawnings in stickleback females each spawning season is unaffected by S. solidus infection. Thus, annual fecundity appears to be reduced only through recruitment of oocytes into vitellogenesis. PMID:20128945

  16. Ovarian development in athymic nude mice. II. The growth of the oocyte and follicle.

    PubMed

    Lintern-Moore, S; Pantelouris, E M

    1975-01-01

    Congenitally athymic mice homozygous for the Mendelian recessive mutation "nude" develop well defined morphological and quantitative changes in the ovarian follicle population. A decline in follicle numbers at 2 months of age is preceded by a retardation in follicle growth at 1 month of age. The growth of the oocyte and its nucleus are not affected by the nude mutation. However, the rate of growth and maximum size of the oocyte nucleolus are reduced in nudes. These developmental events are discussed in relation to the genetic activity of the oocyte, the role of pituitary gonadotrophins in follicular and oocyte growth and the possible role of the thymus gland in these processes. PMID:1228337

  17. Effects of dimethyl sulfoxide on asymmetric division and cytokinesis in mouse oocytes

    PubMed Central

    2014-01-01

    Background Dimethyl sulfoxide (DMSO) is used extensively as a permeable cryoprotectant and is a common solvent utilized for several water-insoluble substances. DMSO has various biological and pharmacological activities; however, the effect of DMSO on mouse oocyte meiotic maturation remains unknown. Results In DMSO-treated oocytes, we observed abnormal MII oocytes that contained large polar bodies, including 2-cell–like MII oocytes, during in vitro maturation. Oocyte polarization did not occur, due to the absence of actin cap formation and spindle migration. These features are among the primary causes of abnormal symmetric division; however, analysis of the mRNA expression levels of genes related to asymmetric division revealed no significant difference in the expression of these factors between the 3% DMSO-treated group and the control group. After each “blastomere” of the 2-cell–like MII stage oocytes was injected by one sperm head respectively, the oocytes still possessed the ability to extrude the second polar body from each “blastomere” and to begin cleavage. However, MII oocytes with large polar bodies developed to the blastocyst stage after intracytoplasmic sperm injection (ICSI). Furthermore, other permeable cryoprotectants, such as ethylene glycol and glycerol, also caused asymmetric division failure. Conclusion Permeable cryoprotectants, such as DMSO, ethylene glycol, and glycerol, affect asymmetric division. DMSO disrupts cytokinesis completion by inhibiting cortical reorganization and polarization. Oocytes that undergo symmetric division maintain the ability to begin cleavage after ICSI. PMID:24953160

  18. Assessing high wind energy penetration

    Microsoft Academic Search

    John Olav Tande

    1995-01-01

    In order to convincingly promote installing wind power capacity as a substantial part of the energy supply system, a set of careful analyses must be undertaken. This paper applies a case study concentrated on assessing the cost\\/benefit of high wind energy penetration. The case study considers expanding the grid connected wind power capacity in Praia, the capital of Cape Verde.

  19. FAA Fluorescent Penetrant Laboratory Inspections

    SciTech Connect

    WINDES,CONNOR L.; MOORE,DAVID G.

    2000-08-02

    The Federal Aviation Administration Airworthiness Assurance NDI Validation Center currently assesses the capability of various non-destructive inspection (NDI) methods used for analyzing aircraft components. The focus of one such exercise is to evaluate the sensitivity of fluorescent liquid penetrant inspection. A baseline procedure using the water-washable fluorescent penetrant method defines a foundation for comparing the brightness of low cycle fatigue cracks in titanium test panels. The analysis of deviations in the baseline procedure will determine an acceptable range of operation for the steps in the inspection process. The data also gives insight into the depth of each crack and which step(s) of the inspection process most affect penetrant sensitivities. A set of six low cycle fatigue cracks produced in 6.35-mm thick Ti-6Al-4V specimens was used to conduct the experiments to produce sensitivity data. The results will document the consistency of the crack readings and compare previous experiments to find the best parameters for water-washable penetrant.

  20. Penetrating abdominal injuries: management controversies

    Microsoft Academic Search

    Muhammad U Butt; Nikolaos Zacharias; George C Velmahos

    2009-01-01

    Penetrating abdominal injuries have been traditionally managed by routine laparotomy. New understanding of trajectories, potential for organ injury, and correlation with advanced radiographic imaging has allowed a shift towards non-operative management of appropriate cases. Although a selective approach has been established for stab wounds, the management of abdominal gunshot wounds remains a matter of controversy. In this chapter we describe

  1. A penetration-aspiration scale

    Microsoft Academic Search

    John C. Rosenbek; Jo Anne Robbins; Ellen B. Roecker; Jame L. Coyle; Jennifer L. Wood

    1996-01-01

    The development and use of an 8-point, equalappearing interval scale to describe, penetration and aspiration events are described. Scores are determined primarily by the depth to which material passes in the airway and by whether or not material entering the airway is expelled. Intra-and interjudge reliability have been established. Clinical and scientific uses of the scale are discussed.

  2. Membrane transfer from oocyte to sperm occurs in two CD9-independent ways that do not supply the fertilising ability of Cd9-deleted oocytes.

    PubMed

    Barraud-Lange, Virginie; Chalas Boissonnas, Céline; Serres, Catherine; Auer, Jana; Schmitt, Alain; Lefèvre, Brigitte; Wolf, Jean-Philippe; Ziyyat, Ahmed

    2012-07-01

    Spermatozoa undergo regulation of their functions along their lifespan through exchanges via vesicles or interactions with epithelial cells, in the epididymis, in the seminal fluid and in the female genital tract. Two different ways of oocyte membrane transfer to spermatozoa have been described: trogocytosis and exosomes. We here report an analysis of in vitro exchanges between the membranes of unfertilised oocytes and capacitated spermatozoa. We showed that optimum conditions are fulfilled when unfertilised oocytes interact with acrosome-reacted spermatozoa, a scenario mimicking the events occurring when the fertilising spermatozoon is inside the perivitelline space. Although CD9 tetraspanin is an essential molecule for fertilisation, exosome and trogocytosis transfer persists in Cd9-null oocytes in spite of their dramatic fusion failure. These exchanges are CD9 tetraspanin independent. We also confirm that mice sperm express CD9 tetraspanin and that when Cd9-null oocytes were inseminated with sperm covered with oocyte membrane materials, including CD9 tetraspanin, no rescue of the oocytes' fertilisability could be obtained. Thus, the existence of two ways of exchange between gametes during fertilisation suggests that these events could be of a physiological importance in this process. PMID:22554680

  3. Long-term radioimmunotherapy studies of Cu-64 anti-colon carcinoma monoclonal antibody (MAb)-1A3, intact and F(ab{prime}){sub 2} singly and in combination, in the GW39-hamster model

    SciTech Connect

    Connett, J.M.; Anderson, C.J.; Guo, L.W. [Washington Univ. School of Medicine, St. Louis, MO (United States)] [and others

    1996-05-01

    In previous studies we have shown that Cu-64 has potential for use in radioimmunotherapy (RIT). The present study was undertaken to examine the therapeutic potential of Cu-64-benzyl-TETA-MAb 1A3, intact and F(ab{prime}){sub 2} fragments, injected single or in combination. Using the model of hamsters carrying the GW39 human colon carcinoma in their thighs, we were interested in whether injecting Cu-64-MAb 1A3 intact and F(ab{prime}){sub 2} fragments together would give improved RIT results compared to either agent alone due to the better tumor penetrating properties of F(ab{prime}){sub 2} fragments and the higher uptake and long tumor residence time of intact MAbs. Hamsters were injected with either 1.5 mCi Cu-64-1A3, 1.5 mCi Cu-64-1A3 F(ab{prime}){sub 2} or a combination of 0.75 mCi Cu-64-1A3 intact and 0.75 mCi Cu-64-1A3 F(ab{prime}){sub 2}. These suboptimal doses of Cu-64 were administered in order to detect any enhanced RIT effects with the combination of Cu-64-labeled MAb and fragments. Control groups received saline along. Hamsters were sacrificed when tumors were > 10 g or after surviving for 6 months. Mean lifespans for hamsters treated with Cu-64-1A3 intact, F(ab{prime}){sub 2}, and the combination were 92 {plus_minus} 44 days, 104 {plus_minus} 54 days and 129 {plus_minus} 48 days respectively, compared to 32 {plus_minus} 5 days for the saline controls (p,0.001). 6 months following treatment 43% of the hamsters (3/7) treated with 1.5 mCi Cu-64 1A3 F(ab{prime}){sub 2}, and 50% of hamsters (5/10) treated with 0.75 mCi Cu-64-1A3 and 0.75 mCi Cu-64-1A3 F(ab{prime}){sub 2} in combination were alive and tumor free. Although tumor grown inhibition was also seen in the group receiving 1.5 mCi Cu-64 1A3 intact, only one hamster (1/7) survived tumor free to 6 months. Results show that Cu-64-1A3 F(ab{prime}){sub 2} as well as intact Cu-64-1A3 can increase survival and effect long term tumor inhibition.

  4. Digital multiplexed mRNA analysis of functionally important genes in single human oocytes and correlation of changes in transcript levels with oocyte protein expression?

    PubMed Central

    Riris, Solon; Webster, Philippa; Homer, Hayden

    2014-01-01

    Objective To investigate functionally important transcripts in single human oocytes with the use of NanoString technology and determine whether observed differences are biologically meaningful. Design Analysis of human oocytes with the use of NanoString and immunoblotting. Setting University-affiliated reproductive medicine unit. Patients Women undergoing in vitro fertilization. Intervention Human oocytes were analyzed with the use of NanoString or immunoblotting. Main Outcome Measures The abundance of transcripts for ten functionally important genes—AURKA, AURKC, BUB1, BUB1B (encoding BubR1), CDK1, CHEK1, FYN, MOS, MAP2K1, and WEE2—and six functionally dispensable genes were analyzed with the use of NanoString. BubR1 protein levels in oocytes from younger and older women were compared with the use of immunoblotting. Result(s) All ten functional genes but none of the six dispensable genes were detectable with the use of NanoString in single oocytes. There was 3- to 5-fold variation in BUB1, BUB1B, and CDK1 transcript abundance among individual oocytes from a single patient. Transcripts for these three genes—all players within the spindle assembly checkpoint surveillance mechanism for preventing aneuploidy—were reduced in the same oocyte from an older patient. Mean BUB1B transcripts were reduced by 1.5-fold with aging and associated with marked reductions in BubR1 protein levels. Conclusion(s) The abundance of functionally important transcripts exhibit marked oocyte-to-oocyte heterogeneity to a degree that is sufficient to affect protein expression. Observed variations in transcript abundance are therefore likely to be biologically meaningful, especially if multiple genes within the same pathway are simultaneously affected. PMID:24444598

  5. Analysis of the Phospholipid Profile of Metaphase II Mouse Oocytes Undergoing Vitrification

    PubMed Central

    Bang, Soyoung; Mok, Hyuck Jun; Suh, Chang Suk; Kim, Kwang Pyo; Lim, Hyunjung Jade

    2014-01-01

    Oocyte freezing confers thermal and chemical stress upon the oolemma and various other intracellular structures due to the formation of ice crystals. The lipid profiles of oocytes and embryos are closely associated with both, the degrees of their membrane fluidity, as well as the degree of chilling and freezing injuries that may occur during cryopreservation. In spite of the importance of lipids in the process of cryopreservation, the phospholipid status in oocytes and embryos before and after freezing has not been investigated. In this study, we employed mass spectrometric analysis to examine if vitrification has an effect on the phospholipid profiles of mouse oocytes. Freshly prepared metaphase II mouse oocytes were vitrified using copper grids and stored in liquid nitrogen for 2 weeks. Fresh and vitrified-warmed oocytes were subjected to phospholipid extraction procedure. Mass spectrometric analyses revealed that multiple species of phospholipids are reduced in vitrified-warmed oocytes. LIFT analyses identified 31 underexpressed and 5 overexpressed phospholipids in vitrified mouse oocytes. The intensities of phosphatidylinositol (PI) {18?2/16?0} [M?H]? and phosphatidylglycerol (PG) {14?0/18?2} [M?H]? were decreased the most with fold changes of 30.5 and 19.1 in negative ion mode, respectively. Several sphingomyelins (SM) including SM {d38?3} [M+H]+ and SM {d34?0} [M+K]+ were decreased significantly in positive ion mode. Overall, the declining trend of multiple phospholipids demonstrates that vitrification has a marked effect on phospholipid profiles of oocytes. These results show that the identified phospholipids can be used as potential biomarkers of oocyte undergoing vitrification and will allow for the development of strategies to preserve phospholipids during oocyte cryopreservation. PMID:25033391

  6. CONCENTRATION DEPENDENT ACCUMULATION OF [3H]-DELTAMETHRIN IN SODIUM CHANNEL N AV1.2 EXPRESSING XENOPUS LAEVIS OOCYTES.

    EPA Science Inventory

    Disruption of neuronal voltage-sensitive sodium channels (VSSCs) by pyrethroid insecticides such as deltamethrin (DLT) has been widely studied using Xenopus laevis oocytes transfected with VSSC. However, the extent of pyrethroid accumulation in VSSC-expressing oocytes is unknown....

  7. AMS 102: QUIZ 3 In the town of Rodentville, half of the households own a hamster, 30%

    E-print Network

    Retakh, Alexander

    AMS 102: QUIZ 3 SOLUTIONS In the town of Rodentville, half of the households own a hamster, 30% of all households own a gunia pig, and 35% of all households own neither a hamster, nor a guinea pig. (a) Determine the percentage of households that own both a hamster and a gunie pig. 100 - 35 = 65% of households

  8. Detection of vesicant-induced upper airway mucosa damage in the hamster cheek pouch model using optical

    E-print Network

    Chen, Zhongping

    Detection of vesicant-induced upper airway mucosa damage in the hamster cheek pouch model using Sciences Road Irvine, California 92612 Abstract. Hamster cheek pouches were exposed to 2-chloroethyl ethyl; vesicants; optical coher- ence tomography; hamster cheek pouch model; oral mucosa. Paper 09155RR received

  9. The induction of meiosis by ovaries of newborn hamsters and its relation to the action of the extra ovarian structures

    E-print Network

    Paris-Sud XI, Université de

    The induction of meiosis by ovaries of newborn hamsters and its relation to the action of the extra with the degeneration of practically all germ cells. In the hamster, if ovaries are explanted before 15 days post coitum in the mesovarium. In the hamster, the separation between the ovary and the structures #12;in the mesovarium is very

  10. JOURNAL OF BIOLOGICAL RHYTHMS / December 2001Gorman and Lee / SPLIT ACTIVITY RHYTHMS IN HAMSTERS Daily Novel Wheel Running Reorganizes and

    E-print Network

    Lee, Theresa

    JOURNAL OF BIOLOGICAL RHYTHMS / December 2001Gorman and Lee / SPLIT ACTIVITY RHYTHMS IN HAMSTERS Daily Novel Wheel Running Reorganizes and Splits Hamster Circadian Activity Rhythms Michael R. Gorman1 circadian oscillators. Exposure of male Syrian hamsters to novel running wheels also induces splitting

  11. JOURNAL OF BIOLOGICAL RHYTHMS / December 2001Gorman et al. / SPLIT CIRCADIAN RHYTHMS IN HAMSTERS Temporal Reorganization of the Suprachiasmatic

    E-print Network

    Lee, Theresa

    JOURNAL OF BIOLOGICAL RHYTHMS / December 2001Gorman et al. / SPLIT CIRCADIAN RHYTHMS IN HAMSTERS Temporal Reorganization of the Suprachiasmatic Nuclei in Hamsters with Split Circadian Rhythms Michael R. The refinement of a procedure for splitting hamster rhythms in a 24-h light- dark:light-dark cycle has enabled

  12. Exposure to short days, but not short-term melatonin, enhances humoral immunity of male Syrian hamsters

    E-print Network

    Demas, Greg

    hamsters (Mesocricetus auratus) Introduction In addition to marked seasonal changes in reproductive species (e.g. deer mice, prairie voles, Siberian hamsters) adjust immune function in response to changes function of Syrian hamsters (Mesocricetus auratus), and to determine the role of melatonin in mediating

  13. The role of androgens in the mediation of seasonal territorial aggression in male Siberian hamsters (Phodopus sungorus)

    E-print Network

    Demas, Greg

    The role of androgens in the mediation of seasonal territorial aggression in male Siberian hamsters mechanisms mediating seasonal aggression. Siberian hamsters (Phodopus sungorus) are an ideal study system that circulating gonadal steroids are not necessary to activate aggressive behavior in adult male hamsters. Further

  14. High doses of medroxyprogesterone as the cause of disappearance of adherence of the zona pellucida to an oocyte

    Microsoft Academic Search

    Barbara Jod?owska-J?drych; Marian J?drych; W?odzimierz Matysiak

    2010-01-01

    The zona pellucida (ZP) is an external glycoprotein membrane of oocytes of mammals and embryos in the early stage of their\\u000a development. ZP first appears in growing ovarian follicles as an extracellular substance between the oocyte and granular cells.\\u000a The zona pellucid markedly affects the development and maturation of the oocyte. The morphology of the ZP-oocyte complex allows\\u000a a more

  15. In vitro maturation and fertilization of oocytes from unstimulated normal ovaries, polycystic ovaries, and women with polycystic ovary syndrome

    Microsoft Academic Search

    Tim J. Child; Ahmad Kamal Abdul-Jalil; Bulent Gulekli; Seang Lin Tan

    2001-01-01

    Objective: To investigate differences in immature oocyte maturation, fertilization, and pregnancy rates among women with unstimulated normal ovaries, polycystic ovaries (PCOs), or PCOS.Design: Prospective observational study.Setting: University fertility clinic.Patient(s): One hundred forty-four women undergoing 180 in vitro oocyte maturation treatment cycles.Intervention(s): Transvaginal immature oocyte recovery from unstimulated ovaries 36 hours after hCG priming. In vitro oocyte maturation and fertilization. Fresh

  16. Effect of Various Sugars and Sugar Substitutes on Dental Caries in Hamsters and Rats

    Microsoft Academic Search

    GORAN FROSTELL; PAUL H. KEYES; ANDRACHEL H. LARSON

    Two series of experiments, one in hamsters the other in rats, were conducted to compare the dental caries conduciveness of sucrose with that of several other sugars and carbohydrates. Hamsters and albino rats fed a diet containing 56% sucrose in the form of confectionery sugar developed highly active carious lesions in their molar teeth. The lesions were located on \\

  17. A Comparison of Hamster Anesthetics and Their Effect on Mosquito Blood Feeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hamsters or mice are often anesthetized when they are used as the hosts for insect feeding experiments. An experiment was done to determine if there was a difference in mosquito blood feeding success when fed on hamsters anesthetized using two commonly used protocols. The number of blood-fed females...

  18. Corn fiber oil and sitostanol decrease cholesterol absorption independently of intestinal sterol transporters in hamsters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this study was to investigate the cholesterol-lowering mechanism of corn fiber oil (CFO), ferulate phytostanyl esters (FPE) and parent compounds including sitostanol and ferulic acid in hamsters. Method: Seventy male golden syrian hamsters were randomly assigned to six experimental diets ...

  19. Effect of amiloride on bulk flow and iontophoretic taste stimuli in the hamster

    Microsoft Academic Search

    M. Scott Herness

    1987-01-01

    This investigation 1) demonstrates the effect of amiloride on various taste responses in the hamster, and 2) tests the hypothesis that its action on iontophoretic application of taste stimuli parallels its action on bulk flow delivery. Amiloride has not previously been tested in the hamster nor has its effect on iontophoretic stimuli (socalled ‘electric taste’), which is thought to behave

  20. Photoperiodic regulation of gene expression in brown and white adipose tissue of Siberian hamsters

    E-print Network

    Demas, Greg

    Photoperiodic regulation of gene expression in brown and white adipose tissue of Siberian hamsters expression in brown and white adipose tissue of Siberian hamsters (Phodopus sungorus). Am J Physiol in white adipose tissue (WAT) mass, with peaks in long "sum- merlike" days (LDs) and nadirs in short

  1. Photoperiodic Regulation of Circulating Leukocytes in Juvenile Siberian Hamsters: Mediation by Melatonin and Testosterone

    Microsoft Academic Search

    Brian J. Prendergast; Andrew K. Hotchkiss; Randy J. Nelson

    2003-01-01

    The reproductive system of Siberian hamsters (Phodopus sungorus) undergoes rapid phenotypic responses to changes in day length that occur around the time of weaning. The present experiments tested whether the immune system of Siberian hamsters is similarly photoperiodicearly in life and whether photoperiodic changes in melatonin or gonadal hormone secretions mediate any such responses to day length. Circulating blood leukocyte

  2. Size and Filterability of Human and Hamster Pulmonary Macrophages Exposed to Cigarette Smoke

    Microsoft Academic Search

    Clark M. Smith; David P. Tukey; Ruth Boyd; Dawn J. Garlich; John Hoidal; C. C. Clawson

    1986-01-01

    Pulmonary alveolar macrophages (PAM) obtained from healthy human ciga- rette smokers generated greater pressure in filtration through small cylindrical pores than PAM from nonsmoking controls. A well standardized hamster smok- ing model was employed to study the structural basis for the impaired PAM filtration acompanying cigarette smoke exposure. Hamsters also demonstrated increased PAM filtration pressure through cylindrical pores less than

  3. Soybean protein lowers serum cholesterol levels in hamsters: Effect of debittered undigested fraction

    Microsoft Academic Search

    Marites Gatchalian-Yee; Yoko Arimura; Eiko Ochiai; Koji Yamada; Michihiro Sugano

    1997-01-01

    the undigested fraction (UDF) of soybean protein exerts a marked hypocholesterolemic effect in relation to soybean protein (SOY) in rats. The present study was conducted to confirm whether UDF was effective in hamsters as in rats in combination with different fat sources, either perilla oil (PER) or safflower oil (SAF). Because the hamster, unlike the rat, disliked the bitter taste

  4. Diet affects resting, but not basal metabolic rate of normothermic Siberian hamsters acclimated to winter.

    PubMed

    Gutowski, Jakub P; Wojciechowski, Micha? S; Jefimow, Ma?gorzata

    2011-12-01

    We examined the effect of different dietary supplements on seasonal changes in body mass (m(b)), metabolic rate (MR) and nonshivering thermogenesis (NST) capacity in normothermic Siberian hamsters housed under semi-natural conditions. Once a week standard hamster food was supplemented with either sunflower and flax seeds, rich in polyunsaturated fatty acids (FA), or mealworms, rich in saturated and monounsaturated FA. We found that neither of these dietary supplements affected the hamsters' normal winter decrease in m(b) and fat content nor their basal MR or NST capacity. NST capacity of summer-acclimated hamsters was lower than that of winter-acclimated ones. The composition of total body fat reflected the fat composition of the dietary supplements. Resting MR below the lower critical temperature of the hamsters, and their total serum cholesterol concentration were lower in hamsters fed a diet supplemented with mealworms than in hamsters fed a diet supplemented with seeds. These results indicate that in mealworm-fed hamsters energy expenditure in the cold is lower than in animals eating a seed-supplemented diet, and that the degree of FA unsaturation of diet affects energetics of heterotherms, not only during torpor, but also during normothermy. PMID:21889598

  5. Acquisition of visuomotor behavior after neonatal tectal lesions in the hamster: The role of visual experience

    Microsoft Academic Search

    Barbara L. Finlay; Karen Marder; David Cordon

    1980-01-01

    After neonatal damage to the midbrain tectum, hamsters exhibit as adults substantially reorganized retinal projections to the thalamus and midbrain. The present experiments investigated the pattern of acquisition of a range of visuomotor capacities in Syrian hamsters with neonatal tectal damage and the role of visual experience in this acquisition. Analyses of the time course of visuomotor development and the

  6. On the analysis of neonatal hamster tooth germs with the photon microprobe at Daresbury, UK

    NASA Astrophysics Data System (ADS)

    Tros, G. H. J.; Van Langevelde, F.; Vis, R. D.

    1990-04-01

    Complementary to the micro-PIXE experiments performed on hamster tooth germs to elucidate the role of fluoride during the growth, the photon microprobe at Daresbury was used to obtain information on the distribution of Zn. The germs of fluoride-administered hamsters, together with a control group, were analyzed with the micro-synchrotron radiation fluorescence method (micro-SXRF).

  7. Photoperiod-dependent modulation of anti-Mullerian hormone in female Siberian hamsters, Phodopus sungorus

    Microsoft Academic Search

    Esther W Kabithe

    2008-01-01

    Fertility and fecundity decline with advancing age in female mammals, but reproductive aging was decelerated in Siberian hamsters (Phodopus sungorus) raised in a short-day (SD) photoperiod. Litter success was significantly improved in older hamsters when reared in SD and the number of primordial follicles was twice that of females held in long days (LD). Because anti-Mullerian hormone (AMH) appears to

  8. Developmental analysis of cephalic axial dysraphic disorders in arsenic-treated hamster embryos

    Microsoft Academic Search

    Stanley J. Carpenter

    1987-01-01

    Parenteral injection of pregnant golden hamsters with inorganic arsenic salts early in gestation results, by term, in markedly elevated embryonic-fetal mortality (˜50%) and, in surviving fetuses, a high (˜90%) incidence of cephalic axial dysraphic disorders (“neural tube defects”), particularly exencephaly\\/anencephaly and encephaloceles. The present investigation traces the day by day development of these embryopathic effects of arsenic in the hamster

  9. BODY TEMPERATURE IN THE MOUSE, HAMSTER, AND RAT EXPOSED TO RADIOFREQUENCY RADIATION: AN INTERSPECIES COMPARISON

    EPA Science Inventory

    Colonic temperatures of BALB/c and CBA/J mice, golden hamsters, and Sprague-Dawley rats were taken immediately after exposure for 90 min to radiofrequency (RF) radiation. Exposures were made in 2450 MHz (mouse and hamster) or 600 MHz (rat) waveguide exposure systems while the dos...

  10. Fine structural changes in the hamster pineal gland after blinding and superior cervical ganglionectomy

    Microsoft Academic Search

    Huai-San Lin; Bang-Hsiung Hwang; Chang-Yean Tseng

    1975-01-01

    Pineal glands of male hamsters 8 weeks after removal of both eyes or both superior cervical ganglia and those of untreated animals were studied by electron microscopy. In the blinded hamsters the reproductive organs were remarkably involuted, whereas the pinealocytes enlarged and were characterized by a tremendous hypertrophy of the smoothsurfaced endoplasmic reticulum, in the mesh of which some dense

  11. Weld penetration and defect control

    SciTech Connect

    Chin, B.A.

    1992-05-15

    Highly engineered designs increasingly require the use of improved materials and sophisticated manufacturing techniques. To obtain optimal performance from these engineered products, improved weld properties and joint reliability are a necessarily. This requirement for improved weld performance and reliability has led to the development of high-performance welding systems in which pre-programmed parameters are specified before any welding takes place. These automated systems however lack the ability to compensate for perturbations which arise during the welding process. Hence the need for systems which monitor and control the in-process status of the welding process. This report discusses work carried out on weld penetration indicators and the feasibility of using these indicators for on-line penetration control.

  12. Photorefractive keratectomy following penetrating keratoplasty.

    PubMed

    John, M E; Martines, E; Cvintal, T; Mellor Filho, A; Soter, F; Barbosa de Sousa, M C; Boleyn, K L; Ballew, C

    1994-01-01

    We present 3 eyes that underwent photorefractive keratectomy (PRK) for residual myopia after penetrating keratoplasty, and 1 eye that was treated for recurrent granular dystrophy and myopia following penetrating keratoplasty. The 3 refractive eyes experienced improvements in visual acuity and refractive error through 3 months postoperative, but exhibited regression of effect after 6 months postoperative. One eye also exhibited substantial corneal haze at three months postoperative that was not responsive to steroid retreatment. The eye with granular dystrophy obtained symptomatic relief as well as improvement in vision. We tentatively conclude that the corneal transplant reacts to photorefractive keratectomy in much the same way as a normal cornea. Eyes with substantial degrees of post-graft myopia exhibit regression of refractive effect, much like high myopes following primary photorefractive keratectomy. Photorefractive was unable to prevent the recurrence of granular dystrophy in the transplanted tissue. The eyes reported here achieved only modest long-term visual and refractive improvements. PMID:7517302

  13. Requirements for Phosphorylation of MAP Kinase During Meiosis in Xenopus Oocytes

    Microsoft Academic Search

    James Posada; Jonathan A. Cooper

    1992-01-01

    Mitogen-activated protein (MAP) kinases are activated in response to a variety of extracellular stimuli by phosphorylation on tyrosine and threonine residues. Xp42 is a Xenopus laevis MAP kinase that is activated during oocyte maturation. Modified forms of Xp42 that lacked enzymatic activity or either of the phosphorylation sites were expressed in Xenopus oocytes. When meiotic maturation was induced with progesterone,

  14. Developmental Arrest and Mouse Antral Not-Surrounded Nucleolus Oocytes1

    PubMed Central

    Monti, Manuela; Zanoni, Mario; Calligaro, Alberto; Ko, Minoru S.H.; Mauri, Pierluigi; Redi, Carlo Alberto

    2013-01-01

    ABSTRACT The antral compartment in the ovary consists of two populations of oocytes that differ by their ability to resume meiosis and to develop to the blastocyst stage. For reasons still not entirely clear, antral oocytes termed surrounded nucleolus (SN; 70% of the population of antral oocytes) develop to the blastocyst stage, whereas those called not-surrounded nucleolus (NSN) arrest at two cells. We profiled transcriptomic, proteomic, and morphological characteristics of antral oocytes and observed that NSN oocyte arrest is associated with lack of cytoplasmic lattices coincident with reduced expression of MATER and ribosomal proteins. Cytoplasmic lattices have been shown to store maternally derived mRNA and ribosomes in mammalian oocytes and embryos, and MATER has been shown to be required for cytoplasmic lattice formation. Thus, we isolated antral oocytes from a Matertm/tm mouse and we observed that 84% of oocytes are of the NSN type. Our results provide the first molecular evidence to account for inability of NSN-derived embryos to progress beyond the two-cell stage; these results may be relevant to naturally occurring preimplantation embryo demise in mammals. PMID:23136301

  15. The Use of Fractal Analysis for the Quantification of Oocyte Cytoplasm Morphology

    Microsoft Academic Search

    G. A. Losa; V. Peretti; F. Ciotola; N. Cocchia; G. Vico

    The present study aimed at verifying whether immature cat oocytes with morphologic irregular cytoplasm display self-similar features to be analytically described by fractal analysis. Original images of oocytes collected by ovariectomy were acquired at a final magnification of 400 X with a CCD video camera connected to an optic microscope. After grey thresholding segmentation of cytoplasm, image profiles were submitted

  16. NEDD1 is crucial for meiotic spindle stability and accurate chromosome segregation in mammalian oocytes.

    PubMed

    Ma, Wei; Baumann, Claudia; Viveiros, Maria M

    2010-03-15

    Defects in meiotic spindle structure contribute to chromosome segregation errors leading to genomic instability in oocytes and embryos upon fertilization. In this study, we analyzed the mechanisms that control spindle microtubule nucleation and stability in mammalian oocytes, and identified NEDD1/GCP-WD as a key regulator. NEDD1 specifically co-localizes with gamma-tubulin and pericentrin at microtubule-organizing centers (MTOCs) in mouse oocytes arrested at prophase-I. During metaphase-I and metaphase-II, the protein remains associated with MTOCs, in a pericentrin dependent manner. Notably, knockdown of Nedd1 transcripts using specific siRNAs resulted in a high incidence (65-70%) of metaphase-I arrest. The arrested oocytes were characterized by disrupted meiotic spindle structure, reduced microtubule density and significant chromosome misalignment. Detection of MAD2 at kinetochores indicated an absence of stable chromosome-microtubule attachment as well as activation of the spindle assembly checkpoint (SAC). Importantly, the disruption of meiotic spindle stability was associated with decreased gamma-tubulin at MTOCs in NEDD1-depleted oocytes, as well as a high frequency of chromosome non-disjunction errors leading to aneuploidy (50%) in the oocytes that did progress to metaphase-II. This study demonstrates that NEDD1 is an essential component of acentriolar oocyte MTOCs, which functions in the regulation of meiotic spindle stability. Moreover, it underscores that disruption of spindle stability in oocytes can lead to chromosomes segregation errors that are not fully resolved by SAC. PMID:20079731

  17. Effects of BPA and DES on longchin goby ( Chasmichthys dolichognathus) in vitro during the oocyte maturation

    Microsoft Academic Search

    Hea Ja Baek; In Joon Hwang; Kyung Sun Kim; Young Don Lee; Hyung Bae Kim; Myong Suk Yoo

    2007-01-01

    This study was performed in order to assess whether bisphenol (BPA) and diethylstilbestrol (DES) had agonistic or antagonistic effects on oocyte maturation using marine fish. We tested the effects of these chemicals on in vitro maturation, germinal vesicle breakdown (GVBD), assay using oocytes from the longchin goby, Chasmichthys dolichognathus. During the maturation process, low concentrations of BPA and DES triggered

  18. Inhibition of nuclear maturation of isolated rat oocytes by follicular constituents

    E-print Network

    Paris-Sud XI, Université de

    Inhibition of nuclear maturation of isolated rat oocytes by follicular constituents A. TSAFRIRI the maturation of rat oocytes of (a) porcine FFI and a low molecular weight fraction thereof (PFFI), and (b did not affect the spontaneous resumption of maturation, but GC cultured for 24 hrs before adding

  19. Precocious induction of oocyte maturation and ovulation in rainbow trout (Salmo gairdneri) : problems when using

    E-print Network

    Paris-Sud XI, Université de

    Precocious induction of oocyte maturation and ovulation in rainbow trout (Salmo gairdneri of 3 mg/kg at a 2-day interval) induced oocyte maturation in 94 p. 100 of the fish, but only 25 p. 100 pituitary extract, TPE, containing 3.25 x 10-3 mg/ml of trout gonadotropin, t-GTH) induced maturation in all

  20. Control of oocyte growth and maturation by follicular cells and molecules present in follicular fluid.

    E-print Network

    Paris-Sud XI, Université de

    Review Control of oocyte growth and maturation by follicular cells and molecules present nuclear (resumption as meiosis to reach the Mll stage) or cytoplasmic maturation (ability to fertilize are relevant to the oocyte's nuclear or cytoplasmic maturation. a) Correlation between amounts of specific com

  1. Evolutionary conservation of the oocyte transcriptome among vertebrates and its implications for understanding human reproductive function.

    PubMed

    Sylvestre, Eve-Lyne; Robert, Claude; Pennetier, Sophie; Labrecque, Rémi; Gilbert, Isabelle; Dufort, Isabelle; Léveillé, Marie-Claude; Sirard, Marc-André

    2013-06-01

    Cross-phylum and cross-species comparative transcriptomic analyses provide an evolutionary perspective on how specific tissues use genomic information. A significant mRNA subset present in the oocytes of most vertebrates is stabilized or stored for post-LH surge use. Since transcription is arrested in the oocyte before ovulation, this RNA is important for completing maturation and sustaining embryo development until zygotic genome activation. We compared the human oocyte transcriptome with an oocyte-enriched subset of mouse, bovine and frog (Xenopus laevis) genes in order to evaluate similarities between species. Graded temperature stringency hybridization on a multi-species oocyte cDNA array was used to measure the similarity of preferentially expressed sequences to the human oocyte library. Identity analysis of 679 human orthologs compared with each identified official gene symbol found in the subtractive (somatic-oocyte) libraries comprising our array revealed that bovine/human similarity was greater than mouse/human or frog/human similarity. However, based on protein sequence, mouse/human similarity was greater than bovine/human similarity. Among the genes over-expressed in oocytes relative to somatic tissue in Xenopus, Mus and Bos, a high level of conservation was found relative to humans, especially for genes involved in early embryonic development. PMID:23340479

  2. MicroRNA expression profile in bovine cumulus-oocyte complexes during late oogenesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During late oogenesis, the mammalian oocyte synthesizes and stores mRNA necessary to guide the early stages of embryo development prior to the activation of embryonic transcription. The oocyte also contains many post-transcriptional regulatory mechanisms that coordinate mRNA stability and translati...

  3. Full-term development of mice from enucleated oocytes injected with cumulus cell nuclei [see comments

    Microsoft Academic Search

    T Wakayama; A C Perry; M Zuccotti; K R Johnson; R Yanagimachi

    1998-01-01

    Until recently, fertilization was the only way to produce viable mammalian offspring, a process implicitly involving male and female gametes. However, techniques involving fusion of embryonic or fetal somatic cells with enucleated oocytes have become steadily more successful in generating cloned young. Dolly the sheep was produced by electrofusion of sheep mammary-derived cells with enucleated sheep oocytes. Here we investigate

  4. Cyclic AMP in oocytes controls meiotic prophase I and primordial folliculogenesis in the perinatal mouse ovary.

    PubMed

    Wang, Yijing; Teng, Zhen; Li, Ge; Mu, Xinyi; Wang, Zhengpin; Feng, Lizhao; Niu, Wanbao; Huang, Kun; Xiang, Xi; Wang, Chao; Zhang, Hua; Xia, Guoliang

    2015-01-15

    In mammalian ovaries, a fixed population of primordial follicles forms during the perinatal stage and the oocytes contained within are arrested at the dictyate stage of meiotic prophase I. In the current study, we provide evidence that the level of cyclic AMP (cAMP) in oocytes regulates oocyte meiotic prophase I and primordial folliculogenesis in the perinatal mouse ovary. Our results show that the early meiotic development of oocytes is closely correlated with increased levels of intra-oocyte cAMP. Inhibiting cAMP synthesis in fetal ovaries delayed oocyte meiotic progression and inhibited the disassembly and degradation of synaptonemal complex protein 1. In addition, inhibiting cAMP synthesis in in vitro cultured fetal ovaries prevented primordial follicle formation. Finally, using an in situ oocyte chromosome analysis approach, we found that the dictyate arrest of oocytes is essential for primordial follicle formation under physiological conditions. Taken together, these results suggest a role for cAMP in early meiotic development and primordial follicle formation in the mouse ovary. PMID:25503411

  5. INTRODUCTION At fertilization the sperm and oocyte fuse to form the zygote,

    E-print Network

    Strome, Susan

    the signal for embryogenesis to begin. Shortly after sperm entry an eggshell begins to form and the oocyte not form an eggshell (Ward and Carrel, 1979). Unfertilized oocytes undergo rounds of DNA replication development of early C. elegans embryos. Spe-11 embryos fail to complete meiosis, form a weak eggshell, fail

  6. Redundant control of the Caenorhabditis elegans sperm oocyte switch by PUF-8 and FBF-1,

    E-print Network

    Kimble, Judith

    Redundant control of the Caenorhabditis elegans sperm oocyte switch by PUF-8 and FBF-1, two protein with striking similarity to human Pumilio, prevents return of primary spermatocytes to the mitotic is also critical for the hermaphrodite sperm oocyte switch. Most puf-8 mutant hermaphrodites make both

  7. The effects of heparin exposure on Equine oocytes matured in vitro

    E-print Network

    Evans, Garen Keith

    1995-01-01

    . Oocytes were then transferred to holding media, and examined for loss of cumulus cells. Oocytes were scored as either cumulus free - less than one layer of cells attached to the zona pellucida, or cumulus intact - one or more layers of attached cells...

  8. A Computational Model for Asynchronous Oocyte Growth Dynamics in Spawning Fish

    EPA Science Inventory

    This manuscript describes the development of a computational model that simulates a time course of oocyte growth and spawning for asynchronous spawning fish, based upon plasma vitellogenin concentrations and a critical oocyte size for spawning. The model provides a framework that...

  9. Mouse Oocytes within Germ Cell Cysts and Primordial Follicles Contain a Balbiani Body

    Microsoft Academic Search

    Melissa E. Pepling; James E. Wilhelm; Ashley L. O'Hara; Grant W. Gephardt; Allan C. Spradling

    2007-01-01

    The Balbiani body or mitochondrial cloud is a large distinctive organelle aggregate found in developing oocytes of many species, but its presence in the mouse has been controversial. Using confocal and electron microscopy, we report that a Balbiani body does arise in mouse neonatal germline cysts and oocytes of primordial follicles but disperses as follicles begin to grow. The mouse

  10. Interaction between Polo and BicD proteins links oocyte determination and meiosis control in Drosophila

    E-print Network

    Paris-Sud XI, Université de

    1 Interaction between Polo and BicD proteins links oocyte determination and meiosis control and meiosis control Key words : Polo, BicD, oocyte, meiosis, polarized transport 6999 words 1 INSERM U384 Univ regulatory kinase Polo binds to BicD protein during oogenesis. Polo is expressed in all cells during cyst

  11. Mitochondrial biogenesis and degradation are induced by CCCP treatment of porcine oocytes.

    PubMed

    Itami, N; Shiratsuki, S; Shirasuna, K; Kuwayama, T; Iwata, H

    2015-08-01

    In this study, we investigated the mitochondrial quality control system in porcine oocytes during meiotic maturation. Cumulus cell oocyte complexes (COCs) collected from gilt ovaries were treated with 10??M carbonyl cyanide-m-chlorophenylhydrazone (CCCP; a mitochondrial uncoupler) for 2?h. The CCCP treatment was found to significantly reduce ATP content, increase the amount of phosphorylated AMP-activated protein kinase and elevate reactive oxygen species levels in oocytes. When the CCCP-treated COCs were cultured further for 44?h in maturation medium, the ATP levels were restored and the parthenogenetic developmental rate of oocytes to the blastocyst stage was comparable with that of untreated COCs. To examine the effects of CCCP treatment of oocytes on the kinetics of mitochondrial DNA copy number (Mt number), COCs treated with 0 or 10??M CCCP were cultured for 44?h, after which the Mt number was determined by RT-PCR. CCCP treatment was found to increase the Mt number in the modified maturation medium in which mitochondrial degradation was inhibited by MG132, whereas CCCP treatment did not affect the Mt number in the maturation medium lacking MG132. The relative gene expression of TFAM was furthermore shown to be significantly higher in CCCP-treated oocytes than in untreated oocytes. Taken together, the finding presented here suggest that when the mitochondria are injured, mitochondrial biogenesis and degradation are induced, and that these processes may contribute to the recuperation of oocytes. PMID:25995440

  12. MKlp2 inhibitior paprotrain affects polar body extrusion during mouse oocyte maturation

    PubMed Central

    2013-01-01

    Background Mammalian oocyte meiotic maturation involves a number of important processes, including spindle assembly and migration, cortical reorganization and polar body extrusion. Numerous proteins contribute to these processes, but it is unknown whether MKlp2 (mitotic kinesin-like protein 2; also called KIF20A), a microtubule-associated protein that regulates cytokinesis during mitosis, is involved in oocyte maturation. Methods Confocal microscopy, time lapse microscopy, inhibitor treatment were adopted to examine the roles of MKlp2 in mouse oocyte. Results Immunostaining results showed that MKlp2 localized to oocyte microtubules. Time-lapse microscopy showed that disrupting MKlp2 expression with paprotrain, a specific inhibitor of MKlp2, resulted in polar body extrusion failure. This could be rescued after rescuing oocytes from paprotrain in fresh medium. Cell cycle analysis showed that most oocytes were arrested at metaphase I or telophase I. However, oocyte spindle structure and chromosome alignment were not disrupted after the inhibition of MKlp2 by paprotrain. Conclusions This study demonstrated that MKlp2 is crucial for oocyte maturation by regulating polar body extrusion. PMID:24359300

  13. Hierarchical Molecular Events Driven by Oocyte-Specific Factors Lead to Rapid and Extensive Reprogramming

    PubMed Central

    Jullien, Jerome; Miyamoto, Kei; Pasque, Vincent; Allen, George E.; Bradshaw, Charles R.; Garrett, Nigel J.; Halley-Stott, Richard P.; Kimura, Hiroshi; Ohsumi, Keita; Gurdon, John B.

    2014-01-01

    Summary Nuclear transfer to oocytes is an efficient way to transcriptionally reprogram somatic nuclei, but its mechanisms remain unclear. Here, we identify a sequence of molecular events that leads to rapid transcriptional reprogramming of somatic nuclei after transplantation to Xenopus oocytes. RNA-seq analyses reveal that reprogramming by oocytes results in a selective switch in transcription toward an oocyte rather than pluripotent type, without requiring new protein synthesis. Time-course analyses at the single-nucleus level show that transcriptional reprogramming is induced in most transplanted nuclei in a highly hierarchical manner. We demonstrate that an extensive exchange of somatic- for oocyte-specific factors mediates reprogramming and leads to robust oocyte RNA polymerase II binding and phosphorylation on transplanted chromatin. Moreover, genome-wide binding of oocyte-specific linker histone B4 supports its role in transcriptional reprogramming. Thus, our study reveals the rapid, abundant, and stepwise loading of oocyte-specific factors onto somatic chromatin as important determinants for successful reprogramming. PMID:25066233

  14. In vitro maturation of follicular oocytes of the Giant Panda (Ailuropoda melanoleuca): a case report.

    PubMed

    Zhang, M J; Hou, R; Zhang, A J; Zhang, Z H; He, G X; Li, G H; Wang, J S; Li, S C; Song, Y F; Fei, L S; Chen, H W

    1998-05-01

    The Giant Panda is an endangered species that would benefit from biotechnological assistance in reproduction. However, because there are only a few of these animals left in the world, scientists hesitate to use them for research procedures. We were fortunate to obtain ovaries from a Giant Panda that died of hepatic cirrhosis during the nonbreeding season. Oocytes were harvested within 4 h of death by dissecting the ovarian cortex in physiological saline and collecting the cumulus-oocyte complexes from the fluid, and then were classified into large (> 125 microns) and small (100 to 124 microns) follicular oocytes and placed in TCM199 supplemented with FSH (10 micrograms/mL) and LH (20 micrograms/mL). After culture for 22 h at 37 degrees C in air with 5% CO2, response was evaluated by growth of oocytes and presence of the first polar body. Of the 26 large follicular oocytes that were harvested, 12 were considered suitable for IVM, and 14 were degenerated, had a broken zona pellucida or had lost some cytoplasm. Of the 12 cultured oocytes, all grew to a mean diameter of 141.1(SD = +/- 6.7, n = 12), and 4 released the first polar body. None of the small follicular oocytes showed growth or other signs of maturation. We conclude from our preliminary results that it is possible to obtain functional Giant Panda oocytes from ovaries obtained post mortem during the nonbreeding season. PMID:10732062

  15. Primary structure of Torpedo marmorata chloride channel isolated by expression cloning in Xenopus oocytes

    Microsoft Academic Search

    Thomas J. Jentsch; Klaus Steinmeyer; Gisela Schwarz

    1990-01-01

    A complementary DNA encoding a voltage-gated chloride channel from Torpedo marmorata electric organ was cloned by expressing hybrid-depleted messenger RNA in Xenopus oocytes. The predicted protein has a sequence of 805 amino acids containing several putative membrane-spanning domains. Expression of the protein in Xenopus oocytes shows that it is sufficient for channel function.

  16. Ovarian steroidogenesis in white sturgeon ( Acipenser transmontanus) during oocyte maturation and induced ovulation

    Microsoft Academic Search

    Molly A. H Webb; Grant W Feist; John M Trant; Joel P Van Eenennaam; Martin S Fitzpatrick; Carl B Schreck; Serge I Doroshov

    2002-01-01

    Ovarian follicles and plasma were collected from two female white sturgeon, Acipenser transmontanus, injected with sturgeon pituitary homogenate followed 12h later with GnRHa to induce ovulation. The oocytes of one female underwent germinal vesicle breakdown (GVBD) but ovulation did not occur in response to hormonal stimulation (Female 1), while the oocytes of the other female underwent GVBD and ovulation (Female

  17. Hanging drop monoculture for selection of optimal antioxidants during in vitro maturation of porcine oocytes.

    PubMed

    Ishikawa, S; Machida, R; Hiraga, K; Hiradate, Y; Suda, Y; Tanemura, K

    2014-04-01

    We analysed the effect of three antioxidants that have different functional mechanisms on the in vitro maturation (IVM) of porcine oocytes. Single oocyte monoculture using the hanging drop (HD) system has some advantages such as improving analysis efficiency brought by the smaller number of samples than the number of oocytes cultured in one drop. Direct effects of ligands on single oocytes could also be detected without considering the effects of paracrine factors from other oocytes. After 22 h of pre-culture, denuded oocytes were cultured for 22 h with 0.01 and 0.1 ?g/ml of L-carnitine (LC), lactoferrin (LF) or sulforaphane (SF) in the presence/non-presence of oxidant stress induced by H2O2 supplementation to evaluate the reducing effects against oxidative stress on nuclear maturation. As a result, compared with LC and SF, LF showed effective reduction in oxidative stress at a lower concentration (0.01 ?g/ml), suggesting that LF is a more effective antioxidant in porcine oocyte IVM. Additionally, LF also increased maturation rate even in culture without H2O2. Our results clearly suggest that the HD monoculture system is useful for screening the substances that affect porcine oocyte culture. PMID:24629146

  18. L-carnitine improves hydrogen peroxide-induced impairment of nuclear maturation in porcine oocytes.

    PubMed

    Yazaki, Takako; Hiradate, Yuki; Hoshino, Yumi; Tanemura, Kentaro; Sato, Eimei

    2013-05-01

    We investigated the effect of oxidative stress induced by hydrogen peroxide (H2 O2 ) on lipid peroxide (LPO) level and nuclear maturation in porcine oocytes cultured with or without cumulus cells. After 22?h of pre-culture, oocytes with attached cumulus cells (COC group) or denuded oocytes (DO group) were cultured with H2 O2 , and intra-oocyte H2 O2 and LPO levels were quantitatively analyzed using immunofluorescence. This is the first report evaluating LPO levels in porcine oocytes. After H2 O2 supplementation, the DO group showed severe accumulation of H2 O2 and LPO in the oocytes. Similarly, while inhibition of progression of nuclear maturation was observed in both groups, the effect was more severe in the DO group. These results demonstrate that cumulus cells reduce the accumulation of H2 O2 stress in oocytes. Furthermore, we attempted to reduce the oxidative stress by H2 O2 with L-carnitine, a H2 O2 scavenger. L-carnitine decreased H2 O2 and LPO levels in the oocytes in both groups, and improvement in the progression of impaired nuclear maturation was observed. These effects were different by the presence of cumulus cells. Our results provide that L-carnitine is useful for alleviating H2 O2 -induced oxidative stress by reducing LPO levels and improving the progression of nuclear maturation. PMID:23607575

  19. Effect of dimethylsulphoxide on fertilization of Bovine oocytes matured in vitro 

    E-print Network

    Wavra, Nanette Louise

    1995-01-01

    The objective of this research was to test the sensitivity of in vitro matured bovine oocytes to the addition of the cryoprotectant, DMSO, at room temperature and at O C. In the first experiment, oocytes were randomly assigned to either a 5, 10, 15...

  20. Increased incidence of unpartnered single chromatids in metaphase II oocytes in 39,X(XO) mice

    Microsoft Academic Search

    K. Sakurada; K. Omoe; A. Endo

    1994-01-01

    Since rare cases of sex chromosome anomalies such as XXX and XXY were observed in the offspring of our XO breeder mice, we performed a cytogenetic analysis of metaphase II oocytes of XO mice to determine whether any changes in chromosomal configurations occur. We found a significantly increased incidence of unpartnered single chromatids in metaphase II oocytes of XO mice.

  1. Effects of tributyltin chloride on developing mouse oocytes and preimplantation embryos.

    PubMed

    Huang, Xian-Ju; Shen, Ming; Wang, Lizhong; Yu, Fengxiang; Wu, Wangjun; Liu, Hong-Lin

    2015-04-01

    Tributyltin, an organotin, is ubiquitous in estuaries and freshwater systems. Previous reports suggest that tributyltin is an endocrine disruptor in many wildlife species and it inhibits aromatase in mammalian placental and granulosa-like tumor cell lines. However, no evidence showing the effects of tributyltin on oocytes or preimplantation embryonic developmental competence exists. Therefore, we investigated the role of tributyltin chloride (TBTCl) in the development of female oocytes and preimplantation embryos. Briefly, female ICR mice were gavaged with 0 (vehicle), 4, and 8 mg/kg of TBTCl each day for 18 days. The fluorescence intensity analysis showed that the 5-methylcytosine level decreased after TBTCl treatment, indicating that the general DNA methylation level decreased in the treated oocytes. Our results demonstrate that TBTCl treatment results in decreased mRNA levels of imprinted genes H19, Igf2r, and Peg3 during oocyte growth. The TBTCl-treated oocytes showed a significant increase in reactive oxygen species levels in germinal vesicle oocytes. In TBTCl-treated oocytes, there was no difference in GPx and Sod1 expression, but a decreased mRNA level of Cat occurred when compared with control. Moreover, the blastocysts with TBTCl exposure displayed higher apoptotic signals. These results suggest that TBTCl induces developmental defects in oocytes and preimplantation embryos. PMID:25898838

  2. Identification and characterization of an oocyte factor required for sperm decondensation in pig.

    PubMed

    Li, Jingyu; Huan, Yanjun; Xie, Bingteng; Wang, Jiaqiang; Zhao, Yanhua; Jiao, Mingxia; Huang, Tianqing; Kong, Qingran; Liu, Zhonghua

    2014-10-01

    Mammalian oocytes possess factors to support fertilization and embryonic development, but knowledge on these oocyte-specific factors is limited. In the current study, we demonstrated that porcine oocytes with the first polar body collected at 33?h of in vitro maturation sustain IVF with higher sperm decondensation and pronuclear formation rates and support in vitro development with higher cleavage and blastocyst rates, compared with those collected at 42?h (P<0.05). Proteomic analysis performed to clarify the mechanisms underlying the differences in developmental competence between oocytes collected at 33 and 42?h led to the identification of 18 differentially expressed proteins, among which protein disulfide isomerase associated 3 (PDIA3) was selected for further study. Inhibition of maternal PDIA3 via antibody injection disrupted sperm decondensation; conversely, overexpression of PDIA3 in oocytes improved sperm decondensation. In addition, sperm decondensation failure in PDIA3 antibody-injected oocytes was rescued by dithiothreitol, a commonly used disulfide bond reducer. Our results collectively report that maternal PDIA3 plays a crucial role in sperm decondensation by reducing protamine disulfide bonds in porcine oocytes, supporting its utility as a potential tool for oocyte selection in assisted reproduction techniques. PMID:25030891

  3. A Dynamical Model of Oocyte Maturation Unveils Precisely Orchestrated Meiotic Decisions

    E-print Network

    Lefranc, Marc

    A Dynamical Model of Oocyte Maturation Unveils Precisely Orchestrated Meiotic Decisions Benjamin kinases. In this paper, we propose a dynamical model of the molecular network that orchestrates maturation of Xenopus laevis oocytes. Our model reproduces the core features of maturation progression, including

  4. Maintenance of meiotic prophase arrest in vertebrate oocytes by a Gs protein-mediated pathway

    E-print Network

    Terasaki, Mark

    Maintenance of meiotic prophase arrest in vertebrate oocytes by a Gs protein-mediated pathway, CT 06032, USA b Weis Center for Research, Geisinger Clinic, Danville, PA 17822, USA c Metabolic; Heterotrimeric G proteins; Zebrafish; Xenopus; Mouse Introduction Fully grown oocytes of mammals, frogs and fish

  5. Maternal Diabetes Causes Mitochondrial Dysfunction and Meiotic Defects in Murine Oocytes

    PubMed Central

    Wang, Qiang; Ratchford, Ann M.; Chi, Maggie M.-Y.; Schoeller, Erica; Frolova, Antonina; Schedl, Tim; Moley, Kelle H.

    2009-01-01

    The adverse effects of maternal diabetes on embryo development and pregnancy outcomes have recently been shown to occur as early as the one-cell zygote stage. The hypothesis of this study was that maternally inherited mitochondria in oocytes from diabetic mice are abnormal and thus responsible in part for this latency of developmental compromise. In ovulated oocytes from diabetic mice, transmission electron microscopy revealed an alteration in mitochondrial ultrastructure, and the quantitative analysis of mitochondrial DNA copy number demonstrated an increase. The levels of ATP and tricarboxylic acid cycle metabolites in diabetic oocytes were markedly reduced compared with controls, suggesting a mitochondrial metabolic dysfunction. Abnormal distribution of mitochondria within maturing oocytes also was seen in diabetic mice. Furthermore, oocytes from diabetic mice displayed a higher frequency of spindle defects and chromosome misalignment in meiosis, resulting in increased aneuploidy rates in ovulated oocytes. Collectively, our results suggest that maternal diabetes results in oocyte defects that are transmitted to the fetus by two routes: first, meiotic spindle and chromatin defects result in nondisjunction leading to embryonic aneuploidy; second, structural and functional abnormalities of oocyte mitochondria, through maternal transmission, provide the embryo with a dysfunctional complement of mitochondria that may be propagated during embryogenesis. PMID:19574447

  6. In vitro steroid stimulation of final maturation in oocytes of rock bass (Ambloplites rupestris) (*)

    E-print Network

    Paris-Sud XI, Université de

    In vitro steroid stimulation of final maturation in oocytes of rock bass (Ambloplites rupestris.S.A. Summary. The in vitro effects of various steroids on germinal vesicle break-down (GVBD) in oocytes of rock was peripheral were responsive to steroids in vitro. Of the stimulatory steroids, 17c!, 20(3-dihydroxy-4-pregnen

  7. Zona pellucida surface of immature and in vitro matured mouse oocytes: Analysis by scanning electron microscopy

    Microsoft Academic Search

    J. M. Calafell; C. Nogués; M. Ponsà; J. Santaló; J. Egozcue

    1992-01-01

    Purpose The aim of this work was to determine the morphology of the zona pellucida surface of immature and in vitro matured mouse oocytes by scanning electron microscopy. For this purpose two groups of immature oocytes (germinal vesicle group and metaphase I group) were studied either before or after in vitro maturation.

  8. Experimental Measurement of Human Oocyte Mechanical Properties on a Micro and Nanoforce Sensing Platform Based on Magnetic Springs

    E-print Network

    Paris-Sud XI, Université de

    Experimental Measurement of Human Oocyte Mechanical Properties on a Micro and Nanoforce Sensing and nanoforce sensor used to perform a mechanical characterisation of human oocytes. This device is based and the mechanical evolution of human oocytes during their maturation process can be observed with a force sensor

  9. Improvement of a porcine somatic cell nuclear transfer technique by optimizing donor cell and recipient oocyte preparations

    Microsoft Academic Search

    Gab-sang Lee; Sang-hwan Hyun; Hye-soo Kim; Dae-young Kim; So-hyun Lee; Jeong-mook Lim; Eun-song Lee; Sung-keun Kang; Byeong-chun Lee; Woo-suk Hwang

    2003-01-01

    This study was conducted to improve a porcine somatic cell nuclear transfer (SCNT) technique by optimizing donor cell and recipient oocyte preparations. Adult and fetal fibroblasts, and cumulus and oviduct cells were used as donor cells, and in vivo- and in vitro-matured oocytes were employed as recipient oocytes. The percentages of fusion and development to the blastocyst stage, the ratio

  10. Reversible Disassembly of the Actin Cytoskeleton Improves the Survival Rate and Developmental Competence of Cryopreserved Mouse Oocytes

    Microsoft Academic Search

    Basarab G. Hosu; Steven F. Mullen; John K. Critser; Gabor Forgacs

    2008-01-01

    Effective cryopreservation of oocytes is critically needed in many areas of human reproductive medicine and basic science, such as stem cell research. Currently, oocyte cryopreservation has a low success rate. The goal of this study was to understand the mechanisms associated with oocyte cryopreservation through biophysical means using a mouse model. Specifically, we experimentally investigated the biomechanical properties of the

  11. Ballistic penetration of steel plates

    Microsoft Academic Search

    T. Børvik; M. Langseth; O. S. Hopperstad; K. A. Malo

    1999-01-01

    This paper presents a research programme in progress where the main objective is to study the behaviour of Weldox 460 E steel plates impacted by blunt-nosed cylindrical projectiles in the lower ordnance velocity regime. A compressed gas gun is used to carry out high-precision tests, and a digital high-speed camera system is used to photograph the penetration process. A coupled

  12. Optimization of aerosol penetration through transport lines 

    E-print Network

    Wong Luque, Fermin Samuel

    1992-01-01

    . . Deposition in Isokinetic Inlets. . . . . . . V. RESULTS AND DISCUSSION. . 20 Tubes. . 23 . . . . . . . 24 . . . . . . . 25 28 Penetration through a Model Transport System. Optimum Penetration through Horizontal Penetration through Strom-type Loops.... . Deposition in Isokinetic Inlets. . . , . . . VI. SUMMARY. VII. RECOMMENDED FUTURE RESEARCH 28 Tubes. . 30 . . . . . . . 32 . . . . . . . 34 38 . 40 REFERENCES APPENDIX-A TABLES. APPENDIX-B FIGURES. . . 41 . 46 54 VITA. . 83 LIST OF TABLES...

  13. Mathematical Model for Estimating Perforation Penetration Depth

    Microsoft Academic Search

    A. C. Seibi; F. H. Boukadi; S. Salmi; A. Bemani

    2008-01-01

    This article presents a simplified mathematical model based on the energy-work method to estimate the penetration depth in well perforation. The model uses casing and formation properties in the estimation. It uses the initial speed of the bullet and the failure strengths of the materials resisting penetration as model input. An automated computer program was developed to compute the penetration

  14. Blunt and penetrating trauma to the abdomen

    Microsoft Academic Search

    Jeff Garner

    2005-01-01

    Abdominal trauma may be blunt or penetrating and generates injuries that vary from the insignificant to the immediately life threatening. Blunt trauma to the abdomen is most common in UK and is usually due to road traffic accidents. Penetrating trauma remains relatively rare in the UK, but is increasing in many urban areas. Penetrating trauma predominates in the USA and

  15. Optimal Information Security Investment with Penetration Testing

    E-print Network

    Bencsáth, Boldizsár

    Optimal Information Security Investment with Penetration Testing Rainer B¨ohme and M´ark F techniques, is a relevant tool of information security practitioners. This paper adds penetration testing to the realm of information security investment. Penetration testing is modeled as an information gathering

  16. Mechanisms of projectile penetration in Dyneema encapsulated

    E-print Network

    Wadley, Haydn

    Mechanisms of projectile penetration in DyneemaÒ encapsulated aluminum structures M.R. O: Available online 8 February 2014 Keywords: Ballistic resistance Penetration mechanisms Polymeric composites. This is primarily due to a poor understanding of the mechanics of penetration of these composites in ballistic

  17. Penetration of mantle plumes through depleted lithosphere

    E-print Network

    Brandeis, Geneviève

    Penetration of mantle plumes through depleted lithosphere D. Jurine, C. Jaupart, and G. Brandeis are used to study how a laminar thermal plume deforms and penetrates a buoyant and viscous layer, which deforms the interface. For B penetration into the upper layer occurs with a significant

  18. Bacterial penetration of restored cavities.

    PubMed

    Zivkovi?, S; Bojovi?, S; Pavlica, D

    2001-03-01

    The aim of this study was to assess the quality of the marginal seals of 7 restoratives by means of a bacterial penetration test in vitro. Sixty intact premolars and third molars that were scheduled for extraction were used in the test. There were 2 experimental groups of teeth, as follows: (1) A class V conventional cavity and a wedge erosion cavity were prepared on the buccal surface and the lingual surface, respectively, of each tooth. (2) A class V conventional cavity and a wedge erosion cavity were prepared on the buccal surface and the lingual surface, respectively, of each tooth with a completely removed enamel layer. The cavities were then reconstructed with different restorative materials. The quality of the marginal seals was evaluated by submerging the teeth in a bacterial suspension and incubating them in an anaerobic milieu at 37 degrees C for 20 hours. The teeth were subsequently processed for histologic data and bacterial staining. The best marginal sealing in both the wedge erosion and the class V cavities was provided by the Herculite/Optibond system and the Valux Plus/Scotchbond Multipurpose system. Bacterial penetration was slightly greater with the Luxat compomer and the Dyrect compomer, as well as with Vitremer glass ionomer cement and Fuji LC glass ionomer cement. The bacterial penetration test showed that the use of restorative material does not entirely eliminate microleakage. PMID:11250635

  19. Mechanism of degradation of CPEB during Xenopus oocyte maturation.

    PubMed

    Setoyama, Daiki; Yamashita, Masakane; Sagata, Noriyuki

    2007-11-13

    CPEB, a cytoplasmic polyadenylation element-binding protein, plays an important role in translational control of maternal mRNAs in early animal development. During Xenopus oocyte maturation, CPEB undergoes a Cdc2-mediated phosphorylation- and ubiquitin-dependent degradation that is required for proper entry into meiosis II. However, the precise mechanism of CPEB degradation, including the identity of the responsible E3 ubiquitin ligase, is not known. Here, we show that the SCF(beta-TrCP) E3 ubiquitin ligase complex targets CPEB for degradation during Xenopus oocyte maturation. beta-TrCP, the F-box protein of SCF(beta-TrCP), specifically binds to a sequence (190)TSGFSS(195) (termed here the TSG motif) of CPEB, thereby targeting CPEB for degradation. beta-TrCP binding depends on phosphorylation of Thr-190, Ser-191, and Ser-195 in the TSG motif. Among these residues, Ser-191 is phosphorylated by the Polo-like kinase Plx1, which binds CPEB at a specific Thr-125 residue prephosphorylated by Cdc2. Finally, Cdc2-mediated phosphorylation of other multiple Ser residues, previously implicated in CPEB degradation, is required for both Thr-125 phosphorylation and beta-TrCP binding, presumably causing conformational changes of CPEB. We propose that Cdc2 and Plx1 sequentially phosphorylate CPEB and target it for SCF(beta-TrCP)-dependent degradation in Xenopus oocytes. We suggest that many other proteins carrying the TSG-like motif may be targeted by SCF(beta-TrCP). PMID:17986610

  20. The partition of sodium fluxes in isolated toad oocytes

    PubMed Central

    Dick, D. A. T.; Lea, E. J. A.

    1967-01-01

    1. The rate constant for Na efflux from the oocyte calculated from (d/dt) (ln [Na*]i]) is only approximately 52% of that calculated from (d/dt)[(ln(d[Na*]i)dt)]. The difference may be interpreted by supposing that 48% of the internal Na of the oocyte is either bound to proteins or sequestered in cell organelles. 2. The mean rate constant for Na efflux was 6·4 × 10-3 min-1 corresponding to an apparent Na efflux rate of 13·3 p-mole/cm2.sec. When this is corrected for the increase in surface area produced by microvilli the true efflux rate is 1·1-1·3 p-mole/cm2.sec. 3. The action of ouabain (1-5 ?M) appears to involve two different effects: (a) there is 48-65% inhibition of the membrane Na pump, and (b) there is a release of some of the sequestered Na in the cell. 4. Removal of external K causes a 40% reduction in Na efflux although this value may be an underestimation owing to the presence of K which has leaked from the cell and may be retained near the cell surface. 5. Raising the external K concentration to 15 mM reduces the inhibitory effect of ouabain by approximately a half. 6. It was concluded that the Na pump in the toad oocyte may have a slightly lower level of activity than that in frog muscle, but that its general properties are similar to those in frog muscle and some other animal cells. PMID:6050106

  1. Routing of Biomolecules and Transgenes’ Vectors in Nuclei of Oocytes

    PubMed Central

    Malecki, Marek; Malecki, Bianca

    2012-01-01

    The molecular architecture of Nuclear Pore Complexes (NPCs), as well as the import and export of molecules through them, has been intensively studied in a variety of cells, including oocytes. However, the structures and mechanisms, involved in the transport of molecules beyond the NPCs, remained unclear, until now. The specific aim of this work was, therefore, to determine, if there exist any intranuclear structures in continuum with the NPCs. This information could help in explaining the mechanisms, which propel the distribution of biomolecules and vectors inside the cell nuclei. To attain this aim, we used rapid cryo-immobilization to capture molecular processes of living cells with millisecond resolution. We pursued molecular imaging, including electron energy loss spectroscopy and energy dispersive x-ray spectroscopy, to reveal structures with nanometer spatial resolution. We also bioengineered single chain variable fragments to track biomolecules and transgenes’ constructs. Herein, we reveal the Nuclear Routing Networks (NRNs) in the oocytes of Xenopus laevis. The NRNs originate at and extend from the tops of intranuclear baskets of the NPCs to interconnect them, while creating a complex, intra-nuclear, three-dimensional architecture. The NRNs guide the export of both tRNA, as well as the Nuclear Export Signal (NES) equipped vectors, from the nuclei. Moreover, the NRNs guide the import of both nucleoplasmin, as well as the Nuclear Localization Signals (NLS) modified transgenes’ vectors, into the nuclei. The vectors equipped with these NLS and NES shuttle back and forth through the NPCs and NRNs. To summarize, we reveal the NRN, which functions as the guided distribution system in the Xenopus laevis oocytes’ nuclei. We further proceed with the identification of its molecular components. PMID:22896814

  2. The hamster cheek pouch model for field cancerization studies.

    PubMed

    Monti-Hughes, Andrea; Aromando, Romina F; Pérez, Miguel A; Schwint, Amanda E; Itoiz, Maria E

    2015-02-01

    External carcinogens, such as tobacco and alcohol, induce molecular changes in large areas of oral mucosa, which increase the risk of malignant transformation. This condition, known as 'field cancerization', can be detected in biopsy specimens using histochemical techniques, even before histological alterations are identified. The efficacy of these histochemical techniques as biomarkers of early cancerization must be demonstrated in appropriate models. The hamster cheek pouch oral cancer model, universally employed in biological studies and in studies for the prevention and treatment of oral cancer, is also an excellent model of field cancerization. The carcinogen is applied in solution to the surface of the mucosa and induces alterations that recapitulate the stages of cancerization in human oral mucosa. We have demonstrated that the following can be used for the early detection of cancerized tissue: silver staining of nucleolar organizer regions; the Feulgen reaction to stain DNA followed by ploidy analysis; immunohistochemical analysis of fibroblast growth factor-2, immunohistochemical labeling of proliferating cells to demonstrate an increase of epithelial cell proliferation in the absence of inflammation; and changes in markers of angiogenesis (i.e. those indicating vascular endothelial growth factor activity, endothelial cell proliferation and vascular density). The hamster cheek pouch model of oral cancer was also proposed and validated by our group for boron neutron capture therapy studies for the treatment of oral cancer. Clinical trials of this novel treatment modality have been performed and are underway for certain tumor types and localizations. Having demonstrated the efficacy of boron neutron capture therapy to control tumors in the hamster cheek pouch oral cancer model, we adapted the model for the long-term study of field cancerized tissue. We demonstrated the inhibitory effect of boron neutron capture therapy on tumor development in field cancerized tissue with acceptable levels of mucositis, a dose-limiting side-effect. PMID:25494606

  3. Contribution of human oocyte architecture to success of in vitro maturation technology

    PubMed Central

    Khalili, Mohammad Ali; A Nottola, Stefania; Shahedi, Abbas; Macchiarelli, Guido

    2013-01-01

     The use of ovarian stimulation for infertility treatment is associated with side effects of ovarian hyperstimulation syndrome (OHSS) and potential cancer risk. This is also true in high risk women such as those polycystic with ovary (PCO) and polycystic ovarian syndrome (PCOS). In vitro maturation (IVM) of oocytes was primarily developed to make IVF safe for women with PCO and at high risk of OHSS. The application of IVM of oocytes to assist clinical infertility treatment remains poor because of the reduced developmental competence of oocytes after IVM, despite several decades of research. Reduced meiotic maturation and fertilization rates, as well as low blastocyst production reveal short-term developmental insufficiency of oocytes when compared with in vivo-matured counterparts. In this review, the structural role of human oocytes, revealed by different technical approaches, to the success of IVM technology is highlighted. PMID:24639686

  4. Current results with slow freezing and vitrification of the human oocyte.

    PubMed

    Boldt, Jeffrey

    2011-09-01

    The past decade has witnessed renewed interest in human oocyte cryopreservation (OCP). This article reviews the two general methods used for OCP, slow freezing and vitrification, compares the outcomes associated with each technique and discusses the factors that might influence success with OCP (such as oocyte selection or day of transfer). Based on available data, OCP offers a reliable, reproducible method for preservation of the female gamete and will find increasing application in assisted reproductive technology. Oocyte cryopreservation can provide a number of advantages to couples undergoing assisted reproduction or to women interested in fertility preservation. Two methods, slow freezing and vitrification, have been used successfully for oocyte cryopreservation. This article reviews and compares these methods, and discusses various factors that can impact upon success of oocyte cryopreservation. PMID:21592862

  5. Contribution of human oocyte architecture to success of in vitro maturation technology.

    PubMed

    Khalili, Mohammad Ali; A Nottola, Stefania; Shahedi, Abbas; Macchiarelli, Guido

    2013-01-01

     The use of ovarian stimulation for infertility treatment is associated with side effects of ovarian hyperstimulation syndrome (OHSS) and potential cancer risk. This is also true in high risk women such as those polycystic with ovary (PCO) and polycystic ovarian syndrome (PCOS). In vitro maturation (IVM) of oocytes was primarily developed to make IVF safe for women with PCO and at high risk of OHSS. The application of IVM of oocytes to assist clinical infertility treatment remains poor because of the reduced developmental competence of oocytes after IVM, despite several decades of research. Reduced meiotic maturation and fertilization rates, as well as low blastocyst production reveal short-term developmental insufficiency of oocytes when compared with in vivo-matured counterparts. In this review, the structural role of human oocytes, revealed by different technical approaches, to the success of IVM technology is highlighted. PMID:24639686

  6. Ureteral Injury with Delayed Massive Hematuria after Transvaginal Ultrasound-Guided Oocyte Retrieval

    PubMed Central

    Burnik Papler, Tanja; Vrta?nik Bokal, Eda; Šalamun, Vesna; Gali?, Dejan; Smrkolj, Tomaž; Jan?ar, Nina

    2015-01-01

    We report a case of ureteral injury with delayed hematuria after transvaginal oocyte retrieval. A 28-year-old infertile patient with a history of previous laparoscopic resection of endometriotic nodes of both sacrouterine ligaments presented with abdominal pain one day after oocyte retrieval. Four days after oocyte retrieval, she presented with massive hematuria that reappeared 6 days after oocyte retrieval. Monopolar coagulation with wire electrode and insertion of a double-J-stent was performed during operative cystoscopy. The patient recovered completely after transfusion and had no signs of renal impairment after ureteric stent removal. This is the first report of ureteral injury after oocyte retrieval presenting itself with delayed massive hematuria and no signs of renal dysfunction or urinary leakage into retroperitoneal space. PMID:26146577

  7. Enhanced discrimination of normal oocytes using optically induced pulling-up dielectrophoretic force

    PubMed Central

    Hwang, Hyundoo; Lee, Do-Hyun; Choi, Wonjae; Park, Je-Kyun

    2009-01-01

    We present a method to discriminate normal oocytes in an optoelectrofluidic platform based on the optically induced positive dielectrophoresis (DEP) for in vitro fertilization. By combining the gravity with a pulling-up DEP force that is induced by dynamic image projected from a liquid crystal display, the discrimination performance could be enhanced due to the reduction in friction force acting on the oocytes that are relatively large and heavy cells being affected by the gravity field. The voltage condition of 10 V bias at 1 MHz was applied for moving normal oocytes. The increased difference of moving velocity between normal and starved abnormal oocytes allows us to discriminate the normal ones spontaneously under the moving image pattern. This approach can be useful to develop an automatic and interactive selection tool of fertilizable oocytes. PMID:19693396

  8. Mancozeb adversely affects meiotic spindle organization and fertilization in mouse oocytes.

    PubMed

    Rossi, Gianna; Palmerini, Maria Grazia; Macchiarelli, Guido; Buccione, Roberto; Cecconi, Sandra

    2006-07-01

    In this study the effects of mancozeb, a widely used ethylenebisdithiocarbamate fungicide, on mouse oocyte meiotic maturation and fertilization were analyzed. Oocyte cumulus cell-complexes were matured in vitro with or without increasing concentrations of the fungicide (from 0.001 to 1 microg/ml) that, due to its different stability in organic solvents and in water, was resuspended either in dimethyl sulfoxide or in culture medium. Although, about 95% of oocytes reached the metaphase II stage; mancozeb-exposed oocytes showed a dose-dependent increase of alterations in spindle morphology, and this negative effect was more evident when the fungicide was resuspended in culture medium. Under the latter culture condition, oocytes matured in the presence of 0.1 and 1 microg/ml mancozeb showed a significant reduction also in the formation of male and female pronuclei. These results indicate that mancozeb can adversely affect mammalian reproductive performance, likely by perturbing microtubular organization during meiotic maturation. PMID:16406479

  9. Neural image analysis in the process of quality assessment: domestic pig oocytes

    NASA Astrophysics Data System (ADS)

    Boniecki, P.; Przyby?, J.; Kuzimska, T.; Mueller, W.; Raba, B.; Lewicki, A.; Przyby?, K.; Zaborowicz, M.; Koszela, K.

    2014-04-01

    The questions related to quality classification of animal oocytes are explored by numerous scientific and research centres. This research is important, particularly in the context of improving the breeding value of farm animals. The methods leading to the stimulation of normal development of a larger number of fertilised animal oocytes in extracorporeal conditions are of special importance. Growing interest in the techniques of supported reproduction resulted in searching for new, increasingly effective methods for quality assessment of mammalian gametes and embryos. Progress in the production of in vitro animal embryos in fact depends on proper classification of obtained oocytes. The aim of this paper was the development of an original method for quality assessment of oocytes, performed on the basis of their graphical presentation in the form of microscopic digital images. The classification process was implemented on the basis of the information coded in the form of microphotographic pictures of the oocytes of domestic pig, using the modern methods of neural image analysis.

  10. The promoter of the oocyte-specific gene, Gdf9, is active in population of cultured mouse embryonic stem cells with an oocyte-like phenotype

    Microsoft Academic Search

    Lisa M. Salvador; Celso P. Silva; Igor Kostetskii; Glenn L. Radice; Jerome F. Strauss

    2008-01-01

    The study of germ cell-specific gene regulation in vitro is challenging. Here we report that the promoter of the oocyte-specific gene, Gdf9, is active in a population of cultured murine embryonic stem cells (ES) which have a phenotype resembling oocytes. The promoter region of the murine Gdf9 coupled to enhanced green fluorescent protein (eGFP) was stably transfected into XX mouse

  11. Distribution and metabolism of four different dimethylated arsenicals in hamsters

    SciTech Connect

    Naranmandura, Hua, E-mail: narenman@zju.edu.c [Institute of Pharmacology and Toxicology and Biochemical Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058 (China); Graduate School of Pharmaceutical Sciences, Chiba University, Chuo, Chiba 260-8675 (Japan); Iwata, Katsuya; Suzuki, Kazuo T. [Graduate School of Pharmaceutical Sciences, Chiba University, Chuo, Chiba 260-8675 (Japan); Ogra, Yasumitsu [Laboratory of Chemical Toxicology and Environmental Health, Showa Pharmaceutical University, Machida, Tokyo 194-8543 (Japan)

    2010-05-15

    Arsenic toxicity and distribution are highly dependent on animal species and its chemical species. Recently, thioarsenical has been recognized in highly toxic arsenic metabolites, which was commonly found in human and animal urine. In the present study, we revealed the mechanism underlying the distribution and metabolism of non-thiolated and thiolated dimethylarsenic compounds such as dimethylarsinic acid (DMA{sup V}), dimethylarsinous acid (DMA{sup III}), dimethylmonothioarsinic acid (DMMTA{sup V}), and dimethyldithioarsinic acid (DMDTA{sup V}) after the administration of them into femoral vein of hamsters. DMA{sup V} and DMDTA{sup V} distributed in organs and body fluids were in their unmodified form, while DMA{sup III} and DMMTA{sup V} were bound to proteins and transformed to DMA{sup V} in organs. On the other hand, DMA{sup V} and DMDTA{sup V} were mostly excreted into urine as their intact form 1 h after post-injection, and more than 70% of the doses were recovered in urine as their intact form. By contrast, less than 8-14% of doses were recovered in urine as DMA{sup V}, while more than 60% of doses were distributed in muscles and target organs (liver, kidney, and lung) of hamsters after the injection of DMMTA{sup V} and DMA{sup III}. However, in red blood cells (RBCs), only a small amount of the arsenicals was distributed (less than 4% of the doses) after the injection of DMA{sup III} and DMMTA{sup V}, suggesting that the DMA{sup III} and DMMTA{sup V} were hardly accumulated in hamster RBCs. Based on these observations, we suggest that although DMMTA{sup V} and DMDTA{sup V} are thioarsenicals, DMMTA{sup V} is taken up efficiently by organs, in a manner different from that of DMDTA{sup V}. In addition, the distribution and metabolism of DMMTA{sup V} are like in manner similar to DMA{sup III} in hamsters, while DMDTA{sup V} is in a manner similar to DMA{sup V}.

  12. Quantitative mutagenesis and mutagen screening with Chinese hamster ovary cells

    SciTech Connect

    Hsie, A.W.; San Sebastian, J.R.; Tan, E.L.

    1980-01-01

    A summary is presented on the development of a specific gene mutation assay, the Chinese hamster ovary cells/hypoxanthine-guanine phosphoribosyl transferase (CHO/HGPRT) system, and the utilization of this system to study structure-activity relationship affecting cytotoxicity and gene mutation by various carcinogens. Then, preliminary development and validation of a Multiplex CHO System for the simultaneous determination of chromosome aberration, sister chromatid exchange in addition to cytotoxicity and gene mutation is presented. The potential use of a CHO/human cell hybrid system for measuring chromosomal deletion and loss is discussed.

  13. Photoperiod and social cues influence the medial amygdala but not the bed nucleus of the stria terminalis in the Siberian hamster

    E-print Network

    Breedlove, Marc

    terminalis in the Siberian hamster Bradley M. Cooke, Carol D. Hegstrom1 , Annalise Keen, S. Marc Breedlove or social environment in the Siberian hamster, a seasonally breeding rodent. Adult male hamsters were either hamster (Phodopus sungorus) synchronizes its reproductive behavior with the seasons via photoperiodic

  14. Regulation of expression of microvillus membrane proteins by estrogen in baboon fetal ovarian oocytes.

    PubMed

    Zachos, Nicholas C; Burch, Marcia G; Billiar, Reinhart B; Li, Chunhua; Albrecht, Eugene D; Pepe, Gerald J

    2008-12-01

    We previously demonstrated that the number and height of oocyte microvilli were reduced in baboon fetuses deprived of estrogen in utero and restored to normal in animals supplemented with estradiol. Phosphorylated ezrin and Na+/H+ exchange regulatory factor 1 (NHERF, now termed SLC9A3R1) link f-actin bundles to the membrane, whereas alpha-actinin cross-links f-actin to form microvilli. Therefore, we determined whether these proteins were expressed in oocytes of the fetal baboon ovary and whether expression and/or localization were altered between mid and late gestation in association with an increase in estrogen and in late gestation in animals in which estrogen was suppressed (>95%) or restored by treatment with an aromatase inhibitor with or without estradiol. Expression of alpha-actinin was low at mid gestation, increased on the surface of oocytes of primordial follicles in late gestation, and was negligible in the ovaries of estrogen-suppressed fetuses and normal in animals treated with estrogen. Ezrin (total and phosphorylated) and SLC9A3R1 expression was localized to the surface of oocytes at mid and late gestation in estrogen-replete baboons and to the cytoplasm in late gestation after estrogen suppression. These results are the first to show that the fetal baboon oocyte expressed ezrin, SLC9A3R1, and alpha-actinin, and that these proteins were localized to the oocyte surface consistent with their role in microvilli development in epithelial cells. The current study also showed that the developmental increase in oocyte expression of alpha-actinin is regulated by estrogen and correlated with the estrogen-dependent increase in oocyte microvilli demonstrated previously. Therefore, we propose that development of oocyte microvilli requires expression of alpha-actinin and that expression of alpha-actinin and localization of ezrin-phosphate and SLC9A3R1 to the oocyte membrane are regulated by estrogen. PMID:18716290

  15. IVF for premature ovarian failure: first reported births using oocytes donated from a twin sister

    PubMed Central

    2010-01-01

    Background Premature ovarian failure (POF) remains a clinically challenging entity because in vitro fertilisation (IVF) with donor oocytes is currently the only treatment known to be effective. Methods A 33 year-old nulligravid patient with a normal karyotype was diagnosed with POF; she had a history of failed fertility treatments and had an elevated serum FSH (42 mIU/ml). Oocytes donated by her dizygotic twin sister were used for IVF. The donor had already completed a successful pregnancy herself and subsequently produced a total of 10 oocytes after a combined FSH/LH superovulation regime. These eggs were fertilised with sperm from the recipient's husband via intracytoplasmic injection and two fresh embryos were transferred to the recipient on day three. Results A healthy twin pregnancy resulted from IVF; two boys were delivered by caesarean section at 39 weeks' gestation. Additionally, four embryos were cryopreserved for the recipient's future use. The sister-donor achieved another natural pregnancy six months after oocyte retrieval, resulting in a healthy singleton delivery. Conclusion POF is believed to affect approximately 1% of reproductive age females, and POF patients with a sister who can be an oocyte donor for IVF are rare. Most such IVF patients will conceive from treatment using oocytes from an anonymous oocyte donor. This is the first report of births following sister-donor oocyte IVF in Ireland. Indeed, while sister-donor IVF has been successfully undertaken by IVF units elsewhere, this is the only known case where oocyte donation involved twin sisters. As with all types of donor gamete therapy, pre-treatment counselling is important in the circumstance of sister oocyte donation. PMID:20334702

  16. Fatty acid synthesis and oxidation in cumulus cells support oocyte maturation in bovine.

    PubMed

    Sanchez-Lazo, Laura; Brisard, Daphné; Elis, Sébastien; Maillard, Virginie; Uzbekov, Rustem; Labas, Valérie; Desmarchais, Alice; Papillier, Pascal; Monget, Philippe; Uzbekova, Svetlana

    2014-09-01

    Oocyte meiotic maturation requires energy from various substrates including glucose, amino acids, and lipids. Mitochondrial fatty acid (FA) ?-oxidation (FAO) in the oocyte is required for meiotic maturation, which is accompanied by differential expression of numerous genes involved in FAs metabolism in surrounding cumulus cells (CCs) in vivo. The objective was to elucidate components involved in FAs metabolism in CCs during oocyte maturation. Twenty-seven genes related to lipogenesis, lipolysis, FA transport, and FAO were chosen from comparative transcriptome analysis of bovine CCs before and after maturation in vivo. Using real-time PCR, 22 were significantly upregulated at different times of in vitro maturation (IVM) in relation to oocyte meiosis progression from germinal vesicle breakdown to metaphase-II. Proteins FA synthase, acetyl-coenzyme-A carboxylase, carnitine palmitoyltransferase, perilipin 2, and FA binding protein 3 were detected by Western blot and immunolocalized to CCs and oocyte cytoplasm, with FA binding protein 3 concentrated around oocyte chromatin. By mass spectrometry, CCs lipid profiling was shown to be different before and after IVM. FAO inhibitors etomoxir and mildronate dose-dependently decreased the oocyte maturation rate in vitro. In terms of viability, cumulus enclosed oocytes were more sensitive to etomoxir than denuded oocytes. In CCs, etomoxir (150 ?M) led to downregulation of lipogenesis genes and upregulated lipolysis and FAO genes. Moreover, the number of lipid droplets decreased, whereas several lipid species were more abundant compared with nontreated CCs after IVM. In conclusion, FAs metabolism in CCs is important to maintain metabolic homeostasis and may influence meiosis progression and survival of enclosed oocytes. PMID:25058602

  17. Identification of developmental competence-related genes in mature porcine oocytes

    PubMed Central

    Yuan, Ye; Ida, Jennifer M.; Paczkowski, Melissa; Krisher, Rebecca L.

    2011-01-01

    Oocyte competence is a key factor limiting female fertility, yet the underlying molecular mechanisms that contribute to oocyte competence remain unclear. The objective of this study was to elucidate specific genes whose function contributes to oocyte competence. We observed that 6 of 20 target genes examined were differentially expressed between adult (more competent) and prepubertal (less competent) porcine in vitro matured (IVM) oocytes. These genes were the cholesterol synthesis related gene HMG-CoA reductase (HMGCR), fatty acid oxidation genes acyl-CoA synthetase long-chain family member 3 (ACSL3) and long-chain acyl-CoA dehydrogenase (ACADL), glycolytic genes fructose 1,6 bisphosphate aldolase (ALDOA) and lactate dehydrogenase C (LDHC), and tumor necrosis factor-? (TNF). These 6 genes, as well as 3 other genes (porcine endogenous retrovirus (PERV), transcribed loci 10 (TL10), serine/arginine-rich splicing factor 1 (SRSF1)), were further analyzed by comparing transcript abundance in IVM and in vivo matured (VVM) prepubertal and adult porcine oocytes. Among these 9 target genes, five were differentially expressed between IVM and VVM prepubertal oocytes, while eight genes were differentially expressed between IVM and VVM adult oocytes. None was differentially expressed between VVM prepubertal and adult oocytes. A functional study of TNF demonstrated that depletion of endogenous TNF decreased oocyte competence and TNFAIP6 expression in cumulus cells, while TNF in IVM medium regulated TNFAIP6 expression in cumulus cells. Differential expression of the genes identified in this study suggests that these genes may be functionally relevant to oocyte competence. PMID:21774025

  18. Molecular analysis of the cumulus matrix: insights from mice with O-glycan-deficient oocytes

    PubMed Central

    Ploutarchou, Panayiota; Melo, Pedro; Day, Anthony J; Milner, Caroline M; Williams, Suzannah A

    2015-01-01

    During follicle development, oocytes secrete factors that influence the development of granulosa and cumulus cells (CCs). In response to oocyte and somatic cell signals, CCs produce extracellular matrix (ECM) molecules resulting in cumulus expansion, which is essential for ovulation, fertilisation, and is predictive of oocyte quality. The cumulus ECM is largely made up of hyaluronan (HA), TNF-stimulated gene-6 (TSG-6, also known as TNFAIP6), pentraxin-3 (PTX3), and the heavy chains (HCs) of serum-derived inter-?-inhibitor proteins. In contrast to other in vivo models where modified expansion impairs fertility, the cumulus mass of C1galt1 Mutants, which have oocyte-specific deletion of core 1-derived O-glycans, is modified without impairing fertility. In this report, we used C1galt1 Mutant (C1galt1 FF:ZP3Cre) and Control (C1galt1 FF) mice to investigate how cumulus expansion is affected by oocyte-specific deletion of core 1-derived O-glycans without adversely affecting oocyte quality. Mutant cumulus–oocyte complexes (COCs) are smaller than Controls, with fewer CCs. Interestingly, the CCs in Mutant mice are functionally normal as each cell produced normal levels of the ECM molecules HA, TSG-6, and PTX3. However, HC levels were elevated in Mutant COCs. These data reveal that oocyte glycoproteins carrying core 1-derived O-glycans have a regulatory role in COC development. In addition, our study of Controls indicates that a functional COC can form provided all essential components are present above a minimum threshold level, and thus some variation in ECM composition does not adversely affect oocyte development, ovulation or fertilisation. These data have important implications for IVF and the use of cumulus expansion as a criterion for oocyte assessment. PMID:25855670

  19. MALDI-MS lipid profiles of oocytes recovered by ovum pickup from Bos indicus and 1/2 indicus × taurus with high vs low oocyte yields.

    PubMed

    Silva-Santos, K C; Ferreira, C R; Santos, G M G; Eberlin, M N; Siloto, L S; Rosa, C O; Marcantonio, T N; Seneda, M M

    2014-10-01

    The aim of the present study was to compare the lipid profile in oocytes of indicus and 1/2 indicus × taurus cows with high and low antral follicle count (AFC)/oocyte yields. After an OPU procedure (D0), antral follicles ?3 mm were counted by ultrasonography (D4, 19, 34, 49, 64), and cows were assigned to groups with either high AFC (?30 follicles; indicus, NH group; 1/2 indicus × taurus, AH group) or low AFC (?15 antral follicles; indicus, NL group; 1/2 indicus × taurus, AL group). The lipid profiles of the oocytes were determined by MALDI-MS. For GI, GII and GIII oocytes, the indicus samples tend to cluster separately from the 1/2 indicus × taurus samples. The lipid species [PC (P-38:5) + H](+) and/or [PC (P-36:2) + Na](+) , [PC (38:2) + H](+) , [PC (38:5) + Na](+) and [TAG (60:8) + NH(4) ](+) were more abundant in indicus (NH and NL groups) than 1/2 indicus × taurus. The higher lipid content in the indicus oocytes likely reflects differences in the rate of lipid metabolism and may contribute to oocyte competence and embryo development. PMID:25110198

  20. Taenia solium Oncosphere Adhesion to Intestinal Epithelial and Chinese Hamster Ovary Cells In Vitro?

    PubMed Central

    Verastegui, Manuela; Gilman, Robert H.; Arana, Yanina; Barber, Dylan; Velásquez, Jeanette; Farfán, Marilu; Chile, Nancy; Kosek, Jon C.; Kosek, Margaret; Garcia, Hector H.; Gonzalez, Armando

    2007-01-01

    The specific mechanisms underlying Taenia solium oncosphere adherence and penetration in the host have not been studied previously. We developed an in vitro adhesion model assay to evaluate the mechanisms of T. solium oncosphere adherence to the host cells. The following substrates were used: porcine intestinal mucosal scrapings (PIMS), porcine small intestinal mucosal explants (PSIME), Chinese hamster ovary cells (CHO cells), epithelial cells from ileocecal colorectal adenocarcinoma (HCT-8 cells), and epithelial cells from colorectal adenocarcinoma (Caco-2 cells). CHO cells were used to compare oncosphere adherence to fixed and viable cells, to determine the optimum time of oncosphere incubation, to determine the role of sera and monolayer cell maturation, and to determine the effect of temperature on oncosphere adherence. Light microscopy, scanning microscopy, and transmission microscopy were used to observe morphological characteristics of adhered oncospheres. This study showed in vitro adherence of activated T. solium oncospheres to PIMS, PSIME, monolayer CHO cells, Caco-2 cells, and HCT-8 cells. The reproducibility of T. solium oncosphere adherence was most easily measured with CHO cells. Adherence was enhanced by serum-binding medium with >5% fetal bovine serum, which resulted in a significantly greater number of oncospheres adhering than the number adhering when serum at a concentration less than 2.5% was used (P < 0.05). Oncosphere adherence decreased with incubation of cells at 4°C compared with the adherence at 37°C. Our studies also demonstrated that T. solium oncospheres attach to cells with elongated microvillus processes and that the oncospheres expel external secretory vesicles that have the same oncosphere processes. PMID:17698575

  1. Evaluation of zona pellucida birefringence intensity during in vitro maturation of oocytes from stimulated cycles

    PubMed Central

    2011-01-01

    Background This study evaluated whether there is a relationship between the zona pellucida birefringence (ZP-BF) intensity and the nuclear (NM) and cytoplasmic (CM) in vitro maturation of human oocytes from stimulated cycles. Results The ZP-BF was evaluated under an inverted microscope with a polarizing optical system and was scored as high/positive (when the ZP image presented a uniform and intense birefringence) or low/negative (when the image presented moderate and heterogeneous birefringence). CM was analyzed by evaluating the distribution of cortical granules (CGs) throughout the ooplasm by immunofluorescence staining. CM was classified as: complete, when CG was localized in the periphery; incomplete, when oocytes presented a cluster of CGs in the center; or in transition, when oocytes had both in clusters throughout cytoplasm and distributed in a layer in the cytoplasm periphery Nuclear maturation: From a total of 83 germinal vesicle (GV) stage oocytes, 58 of oocytes (69.9%) reached NM at the metaphase II stage. From these 58 oocytes matured in vitro, the high/positively scoring ZP-BF was presented in 82.7% of oocytes at the GV stage, in 75.8% of oocytes when at the metaphase I, and in 82.7% when oocytes reached MII. No relationship was observed between NM and ZP-BF positive/negative scores (P = 0.55). These variables had a low Pearson's correlation coefficient (r = 0.081). Cytoplasmic maturation: A total of 85 in vitro-matured MII oocytes were fixed for CM evaluation. Forty-nine oocytes of them (57.6%) showed the complete CM, 30 (61.2%) presented a high/positively scoring ZP-BF and 19 (38.8%) had a low/negatively scoring ZP-BF. From 36 oocytes (42.3%) with incomplete CM, 18 (50%) presented a high/positively scoring ZPBF and 18 (50%) had a low/negatively scoring ZP-BF. No relationship was observed between CM and ZP-BF positive/negative scores (P = 0.42). These variables had a low Pearson's correlation coefficient (r = 0.11). Conclusions The current study demonstrated an absence of relationship between ZP-BF high/positive or low/negative score and nuclear and cytoplasmic in vitro maturation of oocytes from stimulation cycles. PMID:21513548

  2. GnRH agonist versus GnRH antagonist in assisted reproduction cycles: oocyte morphology

    PubMed Central

    2012-01-01

    Background The selection of developmentally competent human gametes may increase the efficiency of assisted reproduction. Spermatozoa and oocytes are usually assessed according to morphological criteria. Oocyte morphology can be affected by the age, genetic characteristics, and factors related to controlled ovarian stimulation. However, there is a lack of evidence in the literature concerning the effect of gonadotropin-releasing hormone (GnRH) analogues, either agonists or antagonists, on oocyte morphology. The aim of this randomized study was to investigate whether the prevalence of oocyte dysmorphism is influenced by the type of pituitary suppression used in ovarian stimulation. Methods A total of 64 patients in the first intracytoplasmic sperm injection (ICSI) cycle were prospectively randomized to receive treatment with either a GnRH agonist with a long-term protocol (n: 32) or a GnRH antagonist with a multi-dose protocol (n: 32). Before being subjected to ICSI, the oocytes at metaphase II from both groups were morphologically analyzed under an inverted light microscope at 400x magnification. The oocytes were classified as follows: normal or with cytoplasmic dysmorphism, extracytoplasmic dysmorphism, or both. The number of dysmorphic oocytes per total number of oocytes was analyzed. Results Out of a total of 681 oocytes, 189 (27.8?%) were morphologically normal, 220 (32.3?%) showed cytoplasmic dysmorphism, 124 (18.2%) showed extracytoplasmic alterations, and 148 (21.7%) exhibited both types of dysmorphism. No significant difference in oocyte dysmorphism was observed between the agonist- and antagonist-treated groups (P???0.05). Analysis for each dysmorphism revealed that the most common conditions were alterations in polar body shape (31.3%) and the presence of diffuse cytoplasmic granulations (22.8%), refractile bodies (18.5%) and central cytoplasmic granulations (13.6%). There was no significant difference among individual oocyte dysmorphisms in the agonist- and antagonist-treated groups (P???0.05). Conclusions Our randomized data indicate that in terms of the quality of oocyte morphology, there is no difference between the antagonist multi-dose protocol and the long-term agonist protocol. If a GnRH analogue used for pituitary suppression in IVF cycles influences the prevalence of oocyte dysmorphisms, there does not appear to be a difference between the use of an agonist as opposed to an antagonist. PMID:22540993

  3. Primate follicular development and oocyte maturation in vitro

    PubMed Central

    Xu, Jing; Xu, Min; Bernuci, Marcelo P; Fisher, Thomas E; Shea, Lonnie D; Woodruff, Teresa K; Zelinski, Mary B; Stouffer, Richard L

    2014-01-01

    The factors and processes involved in primate follicular development are complex and not fully understood. An encapsulated three-dimensional (3D) follicle culture system could be a valuable in vitro model to study the dynamics and regulation of folliculogenesis in intact individual follicles in primates. Besides the research relevance, in vitro follicle maturation (IFM) is emerging as a promising approach to offer options for fertility preservation in female patients with cancer. This review summarizes the current published data on in vitro follicular development from the preantral to small antral stage in nonhuman primates, including follicle survival and growth, endocrine (ovarian steroid hormone) and paracrine/autocrine (local factor) function, as well as oocyte maturation and fertilization. Future directions include major challenges and strategies to further improve follicular growth and differentiation with oocytes competent for in vitro fertilization and subsequent embryonic development, as well as opportunities to investigate primate folliculogenesis by utilizing this 3D culture system. The information may be valuable in identifying optimal conditions for human follicle culture, with the ultimate goal of translating the experimental results and products to patients, thereby facilitating diagnostic and therapeutic approaches for female fertility. PMID:24097381

  4. Calcium and actin in the saga of awakening oocytes.

    PubMed

    Santella, Luigia; Limatola, Nunzia; Chun, Jong T

    2015-04-24

    The interaction of the spermatozoon with the egg at fertilization remains one of the most fascinating mysteries of life. Much of our scientific knowledge on fertilization comes from studies on sea urchin and starfish, which provide plenty of gametes. Large and transparent, these eggs have served as excellent model systems for studying egg activation and embryo development in seawater, a plain natural medium. Starfish oocytes allow the study of the cortical, cytoplasmic and nuclear changes during the meiotic maturation process, which can also be triggered in vitro by hormonal stimulation. These morphological and biochemical changes ensure successful fertilization of the eggs at the first metaphase. On the other hand, sea urchin eggs are fertilized after the completion of meiosis, and are particularly suitable for the study of sperm-egg interaction, early events of egg activation, and embryonic development, as a large number of mature eggs can be fertilized synchronously. Starfish and sea urchin eggs undergo abrupt changes in the cytoskeleton and ion fluxes in response to the fertilizing spermatozoon. The plasma membrane and cortex of an egg thus represent "excitable media" that quickly respond to the stimulus with the Ca(2+) swings and structural changes. In this article, we review some of the key findings on the rapid dynamic rearrangements of the actin cytoskeleton in the oocyte/egg cortex upon hormonal or sperm stimulation and their roles in the modulation of the Ca(2+) signals and in the control of monospermic fertilization. PMID:25998739

  5. Social forces can impact the circadian clocks of cohabiting hamsters.

    PubMed

    Paul, Matthew J; Indic, Premananda; Schwartz, William J

    2014-03-22

    A number of field and laboratory studies have shown that the social environment influences daily rhythms in numerous species. However, underlying mechanisms, including the circadian system's role, are not known. Obstacles to this research have been the inability to track and objectively analyse rhythms of individual animals housed together. Here, we employed temperature dataloggers to track individual body temperature rhythms of pairs of cohabiting male Syrian hamsters (Mesocricetus auratus) in constant darkness and applied a continuous wavelet transform to determine the phase of rhythm onset before, during, and after cohabitation. Cohabitation altered the predicted trajectory of rhythm onsets in 34% of individuals, representing 58% of pairs, compared to 12% of hamsters single-housed as 'virtual pair' controls. Deviation from the predicted trajectory was by a change in circadian period (?), which tended to be asymmetric-affecting one individual of the pair in nine of 11 affected pairs-with hints that dominance might play a role. These data implicate a change in the speed of the circadian clock as one mechanism whereby social factors can alter daily rhythms. Miniature dataloggers coupled with wavelet analyses should provide powerful tools for future studies investigating the principles and mechanisms mediating social influences on daily timing. PMID:24500164

  6. Rift Valley fever virus infection in golden Syrian hamsters.

    PubMed

    Scharton, Dionna; Van Wettere, Arnaud J; Bailey, Kevin W; Vest, Zachary; Westover, Jonna B; Siddharthan, Venkatraman; Gowen, Brian B

    2015-01-01

    Rift Valley fever virus (RVFV) is a formidable pathogen that causes severe disease and abortion in a variety of livestock species and a range of disease in humans that includes hemorrhagic fever, fulminant hepatitis, encephalitis and blindness. The natural transmission cycle involves mosquito vectors, but exposure can also occur through contact with infected fluids and tissues. The lack of approved antiviral therapies and vaccines for human use underlies the importance of small animal models for proof-of-concept efficacy studies. Several mouse and rat models of RVFV infection have been well characterized and provide useful systems for the study of certain aspects of pathogenesis, as well as antiviral drug and vaccine development. However, certain host-directed therapeutics may not act on mouse or rat pathways. Here, we describe the natural history of disease in golden Syrian hamsters challenged subcutaneously with the pathogenic ZH501 strain of RVFV. Peracute disease resulted in rapid lethality within 2 to 3 days of RVFV challenge. High titer viremia and substantial viral loads were observed in most tissues examined; however, histopathology and immunostaining for RVFV antigen were largely restricted to the liver. Acute hepatocellular necrosis associated with a strong presence of viral antigen in the hepatocytes indicates that fulminant hepatitis is the likely cause of mortality. Further studies to assess the susceptibility and disease progression following respiratory route exposure are warranted. The use of the hamsters to model RVFV infection is suitable for early stage antiviral drug and vaccine development studies. PMID:25607955

  7. Uterine progesterone receptors in the aged golden hamster.

    PubMed

    Blaha, G C; Leavitt, W W

    1978-11-01

    Uterine capacity to form cytoplasmic progesterone receptor was compared in ovariectomized golden hamsters at three months and 15-17 months of age. A dose-response test with 17beta-estradiol(E2) showed that the uterine content of progesterone receptor (pmole/uterus) was equal in young and old at all dose levels. However, heavier old uteri had less receptor per gm tissue. Old and young hamsters were mated, ovariectomized on day 7 post coitum and after two weeks, all were given the same dose of E2. Endometrium was separated from myometrium before analysis of progesterone receptor. Myometrium was analyzed for both estrogen and progesterone receptors. Myometrium of both groups had comparable levels of both receptors. The mean concentration of progresterone receptor (pmole/gm tissue) was higher in old endometrium. Some old animals with liver, kidney and adrenal disease had more endometrial reaction after E2 treatment. A few with low endometrial receptor levels had normal livers but at least one sterile uterine horn. There was, however, no general decline with age in intrinsic uterine capacity to form progesterone receptors. PMID:744855

  8. Acid-induced secretory cell metaplasia in hamster bronchi

    SciTech Connect

    Christensen, T.G.; Lucey, E.C.; Breuer, R.; Snider, G.L.

    1988-02-01

    Hamsters were exposed to an intratracheal instillation of 0.5 ml of 0.08 N nitric, hydrochloric, or sulfuric acid to determine their airway epithelial response. Three weeks after exposure, the left intrapulmonary bronchi in Alcian blue/PAS-strained paraffin sections were evaluated for the amount of secretory product in the airway epithelium as a measure of secretory cell metaplasia (SCM). Compared to saline-treated control animals, all three acids caused statistically significant SCM. In addition to the bronchial lesion, all three acids caused similar interstitial fibrosis, bronchiolectasis, and bronchiolization of alveoli that varied in individual animals from mild to severe. In a separate experiment to study the persistence of the SCM, hamsters treated with a single instillation of 0.1 N nitric acid showed significant SCM 3, 7, and 17 weeks after exposure. There was a high correlation (r = 0.96) between a subjective assessment of SCM and objective assessment using a digital image-analysis system. We conclude that protons induce SCM independently of the associated anion; the SCM persists at least 17 weeks. Sulfuric acid is an atmospheric pollutant and nitric acid may form locally on the mucosa of lungs exposed to nitrogen dioxide. These acids may contribute to the development of maintenance of the SCM seen in the conducting airways of humans with chronic obstructive pulmonary disease.

  9. Social forces can impact the circadian clocks of cohabiting hamsters

    PubMed Central

    Paul, Matthew J.; Indic, Premananda; Schwartz, William J.

    2014-01-01

    A number of field and laboratory studies have shown that the social environment influences daily rhythms in numerous species. However, underlying mechanisms, including the circadian system's role, are not known. Obstacles to this research have been the inability to track and objectively analyse rhythms of individual animals housed together. Here, we employed temperature dataloggers to track individual body temperature rhythms of pairs of cohabiting male Syrian hamsters (Mesocricetus auratus) in constant darkness and applied a continuous wavelet transform to determine the phase of rhythm onset before, during, and after cohabitation. Cohabitation altered the predicted trajectory of rhythm onsets in 34% of individuals, representing 58% of pairs, compared to 12% of hamsters single-housed as ‘virtual pair’ controls. Deviation from the predicted trajectory was by a change in circadian period (?), which tended to be asymmetric—affecting one individual of the pair in nine of 11 affected pairs—with hints that dominance might play a role. These data implicate a change in the speed of the circadian clock as one mechanism whereby social factors can alter daily rhythms. Miniature dataloggers coupled with wavelet analyses should provide powerful tools for future studies investigating the principles and mechanisms mediating social influences on daily timing. PMID:24500164

  10. Role of luteinizing hormone in luteotropic complex of pregnant hamster

    SciTech Connect

    Tamura, H.; Greenwald, G.S.

    1987-04-01

    Hamsters were hypophysectomized on day 4 of pregnancy and injected subcutaneously on days 4-7 with various combinations of 200 ..mu..g prolactin (Prl), 10 ..mu..g follicle-stimulating hormone (FSH), and 20 ..mu..g luteinizing hormone (LH) in polyvinylpyrrolidone (PVP) to decrease its rate of absorption or in saline. End points for luteal function on day 8 were maintenance of pregnancy, serum progesterone (P/sub 4/), luteal weight, and luteal binding for human chorionic gonadotropin, FSH, and Prl. After hypophysectomy, a drastic decline occurred in all parameters including an 89% decrease in luteal weight. Injection of Prl did not maintain pregnancy nor serum P/sub 4/ but partially maintained luteal weight and human chorionic gonadotropin binding sites per corpus luteum. The minimal luteotropic complex of Prl and FSH was effective in maintaining pregnancy and significantly increased serum P/sub 4/ and Prl and FSH receptors but not to control levels. Thus, the luteotropic activity of LH was only demonstrable when it was injected in a long-acting form; when delivered as a bolus, LH (saline) was luteolytic. P/sub 4/ and estradiol were measured by radioimmunoassay. Radioiodinated gonadotropins were prepared. The percentage of tracer reacting with an excess of receptor were 51% of /sup 125/I-FSH and 45.9% of /sup 125/I-hCG using whole homogenates of hamster ovaries.

  11. An experimental transplantable osteosarcoma with spontaneous pulmonary metastasis in hamsters.

    PubMed Central

    Sekiguchi, M.; Satomura, T.; Saëgusa, M.; Takeuchi, H.; Asanuma, K.; Shimoda, T.

    1994-01-01

    Animal models of osteosarcoma with spontaneous pulmonary metastasis which retain metastatic capacity and osteoid formation after serial passages have been reported infrequently. In this communication we describe some biological features of a transplantable osteosarcoma, Os515, induced by BK-virus in Syrian golden hamsters. The subcutaneously transplanted tumours in 2-week-old animals grew progressively until death, with a mean survival time of 32 days. Distant metastases occurred only in the lungs in all animals. The histological appearance was osteosarcoma of osteoblastic type. Enzyme-histochemical staining showed alkaline phosphatase activity in many cells and beta-glucuronidase activity in few cells. Tumours transplanted intramuscularly in the hind limbs were amputated radically at 5 or 11 days. A small number of animals died from lung metastases without local relapse during the observation period of 140 days after grafting. All the control hamsters bearing unamputated tumours died much earlier. Necropsy revealed large metastatic nodules in the lungs of limb-amputated animals and small diffuse nodules in the lungs of untreated control animals. The development of lung metastases was monitored by soft X-ray without sacrificing the animals. This model will be useful in studies of mechanisms of metastasis and for the experimental treatment of osteosarcoma. Images Figure 1 Figure 3 Figure 4 Figure 5 Figure 10 PMID:8142274

  12. Lymphoreticular and myeloid pathogenesis of Venezuelan equine encephalitis in hamsters.

    PubMed Central

    Walker, D. H.; Harrison, A.; Murphy, K.; Flemister, M.; Murphy, F. A.

    1976-01-01

    Ultrastructural, histopathologic, and virologic studies of adult hamsters infected with virulent Venezuelan equine encelphalomyelitis (VEE) virus (Subtype I-B) demonstrated precise chronologic and topographic progression of lesions and viral replication in extraneural sites. Thymus contained the earliest lesions and the highest initial and subsequent viral titers. No particular cytotropism was observed as highly efficient viral replication and severe cytonecrosis proceded. Early cortical necrosis of splenic periarteriolar lymphocytic sheath was followed by lymphoblastoid repopulation of the peripheral zone. Massive bone marrow necrosis was accompained by ultrastructural evidence of VEE viral particle production in reticulum cells, rubricytes, myeloid cells, lymphoblastoid cells, and megakaryocytes. Speed, efficiency, destructiveness, and relative sensitivity of virtually all lymphoreticular and hematopoetic cells were hallmarks of virulent VEE infection in the hamster. Images Figure 8 Figure 9 Figure 1 Figure 2 Figure 3 Figure 10 Figure 11 Figure 4 Figure 5 Figure 6 Figure 12A and B Figure 13 Figure 7 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 PMID:941983

  13. An Analysis of Hamster Afferent Taste Nerve Response Functions

    PubMed Central

    Frank, Marion

    1973-01-01

    Sensitivities to moderately intense stimuli representing four taste qualities to man were determined for 79 hamster chorda tympani fibers. Some fibers were very sensitive to sucrose, sodium chloride, or hydrochloric acid, but none were very sensitive to quinine. These sensitivities were not randomly distributed among fibers: the sucrose sensitivity was separated from and negatively correlated with the other sensitivities which were associated and positively correlated with each other. Moreover, there were a limited number of sensitivity patterns: (a) fibers responding best to sucrose responded second-best to salt, less to acid, not to quinine; (b) fibers responding best to salt either responded second-best to sucrose and not to acid or quinine; or second-best to acid, less to quinine, and not to sucrose; and (c) fibers responding best to acid responded second-best to salt, more to quinine, and less to sucrose than other fibers. Therefore, if four stimuli of different taste qualities are ordered from acceptable to unacceptable, neural response functions of most hamster chorda tympani taste fibers peak at one point. Sensitivities to nine other moderately intense stimuli which vary in quality to man were also determined for 46–49 of the fibers. Sensitivities to sweet stimuli were always associated with each other and separated from sensitivities to nonsweet stimuli. Sensitivities to nonsweet stimuli were all associated with each other; however, the strongest correlations were between sensitivities to stimuli of like quality, e.g., the three acids or the two sodium salts. PMID:4705639

  14. Global insights into the Chinese hamster and CHO cell transcriptomes.

    PubMed

    Vishwanathan, Nandita; Yongky, Andrew; Johnson, Kathryn C; Fu, Hsu-Yuan; Jacob, Nitya M; Le, Huong; Yusufi, Faraaz N K; Lee, Dong Yup; Hu, Wei-Shou

    2015-05-01

    Transcriptomics is increasingly being used on Chinese hamster ovary (CHO) cells to unveil physiological insights related to their performance during production processes. The rich transcriptome data can be exploited to provide impetus for systems investigation such as modeling the central carbon metabolism or glycosylation pathways, or even building genome-scale models. To harness the power of transcriptome assays, we assembled and annotated a set of RNA-Seq data from multiple CHO cell lines and Chinese hamster tissues, and constructed a DNA microarray. The identity of genes involved in major functional pathways and their transcript levels generated in this study will serve as a reference for future studies employing kinetic models. In particular, the data on glycolysis and glycosylation pathways indicate that the variability of gene expression level among different cell lines and tissues may contribute to their differences in metabolism and glycosylation patterns. Thereby, these insights can potentially lead to opportunities for cell engineering. This repertoire of transcriptome data also enables the identification of potential sequence variants in cell lines and allows tracing of cell lineages. Overall the study is an illustration of the potential benefit of RNA-Seq that is yet to be exploited. PMID:25450749

  15. Demography of penetrating cardiac trauma.

    PubMed Central

    Naughton, M J; Brissie, R M; Bessey, P Q; McEachern, M M; Donald, J M; Laws, H L

    1989-01-01

    All cases of penetrating cardiac trauma in 1985 and 1986 in Jefferson County, Alabama, where patients dying of penetrating trauma received autopsies, were retrospectively reviewed. All hospitals in the county plus the single coroner's office provided the records of the 72 patients comprising this study. Incidents occurred most often in the home or residence (70%) by a known assailant (83%) due to domestic/social disputes (73%). Frequency was greatest in the evening hours (73% between 6:00 PM and 3:00 AM), on weekends in spring and summer. Victims tended to be male (86%), black (72%), married (46%), blue collar workers (62%). There were 41 (57%) gunshot wounds, 3 (4%) shotgun wounds, and 28 (39%) stab wounds with an associated mortality rate of 97%, 100%, and 68%, respectively. Prehospital mortality rate (dead at the scene) was 54.2% (39/72), and death on arrival was 26.4% (19/72), for a combined pretreatment mortality rate of 80.6%. All patients who arrived with no vital signs died. Mortality appeared to be related to mechanism of injury, age, race, sex, vital signs on arrival, number and specific cardiac chambers injured, associated major vascular injury, hematocrit, and mode of transportation. Mortality was not related to caliber of weapon, ethanol level, transport time, time from arrival to operation, or transfusion requirements. There were only ten survivors (1 gunshot wound and 9 stab wounds), all of whom had ventricular injuries and no associated major vascular injuries. The ten survivors represented a 71.4% (10/14) salvage rate for those victims arriving with vital signs. Complications occurred in three patients. Hospitalization averaged 7.3 days in the survivors. Penetrating cardiac trauma remains a serious, socially linked disease with a high rate of mortality. Rapid transport, aggressive resuscitation and cardiorrhaphy remain the best treatment. PMID:2730180

  16. Management of penetrating brain injury

    PubMed Central

    Kazim, Syed Faraz; Shamim, Muhammad Shahzad; Tahir, Muhammad Zubair; Enam, Syed Ather; Waheed, Shahan

    2011-01-01

    Penetrating brain injury (PBI), though less prevalent than closed head trauma, carries a worse prognosis. The publication of Guidelines for the Management of Penetrating Brain Injury in 2001, attempted to standardize the management of PBI. This paper provides a precise and updated account of the medical and surgical management of these unique injuries which still present a significant challenge to practicing neurosurgeons worldwide. The management algorithms presented in this document are based on Guidelines for the Management of Penetrating Brain Injury and the recommendations are from literature published after 2001. Optimum management of PBI requires adequate comprehension of mechanism and pathophysiology of injury. Based on current evidence, we recommend computed tomography scanning as the neuroradiologic modality of choice for PBI patients. Cerebral angiography is recommended in patients with PBI, where there is a high suspicion of vascular injury. It is still debatable whether craniectomy or craniotomy is the best approach in PBI patients. The recent trend is toward a less aggressive debridement of deep-seated bone and missile fragments and a more aggressive antibiotic prophylaxis in an effort to improve outcomes. Cerebrospinal fluid (CSF) leaks are common in PBI patients and surgical correction is recommended for those which do not close spontaneously or are refractory to CSF diversion through a ventricular or lumbar drain. The risk of post-traumatic epilepsy after PBI is high, and therefore, the use of prophylactic anticonvulsants is recommended. Advanced age, suicide attempts, associated coagulopathy, Glasgow coma scale score of 3 with bilaterally fixed and dilated pupils, and high initial intracranial pressure have been correlated with worse outcomes in PBI patients. PMID:21887033

  17. Recombinant human growth differentiation factor-9 improves oocyte reprogramming competence and subsequent development of bovine cloned embryos.

    PubMed

    Su, Jianmin; Hu, Guangdong; Wang, Yongsheng; Liang, Dong; Gao, Mingqing; Sun, Hongzheng; Zhang, Yong

    2014-08-01

    Previously, we found that oocyte-secreted factors (OSFs) secreted by denuded oocytes during in vitro maturation (IVM) enhance subsequent development of bovine somatic cell nuclear transfer (SCNT) embryos. This treatment requires many oocytes during IVM. Hence, the aim of this study was to investigate whether supplementing with recombinant growth differentiation factor-9 (GDF9), one of crucial OFSs, in oocyte maturation medium could improve developmental competence of bovine oocytes and subsequent development of cloned embryos. Cumulus-oocyte complexes (COCs) from antral follicles of bovine ovaries collected from an abattoir were cultured with (SCNT+GDF9 group) or without (SCNT group) 200 ng/mL recombinant human GDF9 in oocyte maturation medium. After 22 h, metaphase II (MII) oocytes were used for SCNT. The presence of 200 ng/mL GDF9 significantly increased oocyte maturation rates, the cleavage rate, and blastocyst formation rates of bovine cloned embryos. The blastocyst total, inner cell mass (ICM) cell numbers, and ratio of ICM:TE were higher, whereas the rate of apoptosis in bovine cloned blastocysts was lower in the SCNT+GDF9 group than in the SCNT group. The histone modifications at various sites were also different between each group. These results suggest that COCs cultured with recombinant GDF9 in oocyte maturation medium improve oocyte developmental competence and subsequent developmental competence of cloned embryo in cattle. PMID:24840335

  18. Maturation rates of vitrified-thawed immature buffalo (Bubalus bubalis) oocytes: effect of different types of cryoprotectants.

    PubMed

    Wani, N A; Misra, A K; Maurya, S N

    2004-09-01

    Cryopreservation of oocytes collected from slaughtered animals of high genetic value, their subsequent utilisation for production of embryos for transfer may provide an opportunity to replenish the valuable germplasm lost. Experiments were conducted to study the effect of cryoprotectants, dimethyl sulfoxide (DMSO), ethylene glycol (EG), 1,2-propanediol (PROH) and glycerol at different concentrations (3.5, 4, 5, 6 and 7 M each with 0.5M sucrose and 0.4% BSA in DPBS) on morphological survival and in vitro maturation of vitrified-thawed immature buffalo oocytes. The cumulus oocyte complexes were harvested from the ovaries obtained from a local slaughterhouse by aspirating the visible follicles. Less number of oocytes reached metaphase-II stage from the oocytes cryopreserved in any of the concentrations of DMSO, EG, PROH and glycerol compared to fresh oocytes. Among the vitrified groups, highest maturation (40.3, 42.5, 40.4 and 23.5%) was obtained in 7 M DMSO, EG, PROH and glycerol, respectively. Oocytes reaching to M-II stage from the oocytes cryopreserved in 7 M glycerol were significantly lower than that of the oocytes vitrified in 7 M DMSO, EG and PROH. It can be concluded that 7 M solutions of DMSO, EG and PROH can be used for vitrification of immature buffalo oocytes for subsequent utilisation of these oocytes in IVM/IVF and embryo production for transfer. PMID:15302375

  19. Controlled loading of cryoprotectants (CPAs) to oocyte with linear and complex CPA profiles on a microfluidic platform†

    PubMed Central

    Heo, Yun Seok; Lee, Ho-Joon; Hassell, Bryan A.; Irimia, Daniel; Toth, Thomas L.; Elmoazzen, Heidi; Toner, Mehmet

    2013-01-01

    Oocyte cryopreservation has become an essential tool in the treatment of infertility by preserving oocytes for women undergoing chemotherapy. However, despite recent advances, pregnancy rates from all cryopreserved oocytes remain low. The inevitable use of the cryoprotectants (CPAs) during preservation affects the viability of the preserved oocytes and pregnancy rates either through CPA toxicity or osmotic injury. Current protocols attempt to reduce CPA toxicity by minimizing CPA concentrations, or by minimizing the volume changes via the step-wise addition of CPAs to the cells. Although the step-wise addition decreases osmotic shock to oocytes, it unfortunately increases toxic injuries due to the long exposure times to CPAs. To address limitations of current protocols and to rationally design protocols that minimize the exposure to CPAs, we developed a microfluidic device for the quantitative measurements of oocyte volume during various CPA loading protocols. We spatially secured a single oocyte on the microfluidic device, created precisely controlled continuous CPA profiles (step-wise, linear and complex) for the addition of CPAs to the oocyte and measured the oocyte volumetric response to each profile. With both linear and complex profiles, we were able to load 1.5 M propanediol to oocytes in less than 15 min and with a volumetric change of less than 10%. Thus, we believe this single oocyte analysis technology will eventually help future advances in assisted reproductive technologies and fertility preservation. PMID:21887438

  20. Effects of equine herpesvirus-9 infection in pregnant mice and hamsters.

    PubMed

    El-Habashi, N; El-Nahass, E; Fukushi, H; Nayel, M; Hibi, D; Sakai, H; Yanai, T

    2011-01-01

    The pathogenicity of equine herpesvirus (EHV)-9, a new neurotropic equine herpesvirus isolated from gazelles, was assessed in pregnant rodents (mice and hamsters) following intranasal inoculation. The pregnant female mice and hamsters were inoculated with EHV-9 in the early or late trimesters. The inoculated animals exhibited mild to severe neurological signs and gave birth to dead or undersized fetuses. All three mice and four hamsters inoculated in the first trimester had varying degrees of placental abnormality, characterized by markedly dilated maternal blood sinusoids, atrophy of the trophoblast cells and necrosis of the middle layer of the trophoblast. There was also endometrial blood vessel congestion and necrosis and disorganization of the fetal capillaries in the mice and hamsters inoculated in the last trimester. EHV-9 antigen was detected in the brain of dams and the lungs of the fetuses and in the middle of the trophoblast layer of the placenta in hamsters inoculated in the first trimester. The placental lesions were milder in mice than in the hamsters. The mice and hamsters inoculated in the last trimester had more prominent lesions than the animals inoculated in the first trimester. These results suggest that EHV-9 can cause the death of the fetus or abortion and that these events may be secondary to placental vascular compromise. PMID:20813378

  1. Effect of monensin on feed utilization and gastrointestinal fermentation in the hamster (Mesocricetus auratus).

    PubMed

    Sakaguchi, E; Matsumoto, T

    1985-07-01

    Three experiments were conducted to examine the effect of monensin on growth performance, feed utilization and volatile fatty acids (VFA) in the forestomach and caecum of hamsters. In Expt 1, monensin was fed at levels of 0, 5, 10 and 20 mg/kg to the growing male and female hamsters given a commercial diet (major component: lucerne (Medicago sativa) meal). In Expt 2, monensin was fed at levels of 0, 5, 15, 45 and 135 mg/kg to the growing male hamsters given a semi-purified diet containing 10 g urea/kg (main components: maize starch, sucrose, casein and cellulose). In Expt 3, monensin was fed at levels of 0 and 40 mg/kg to the growing male hamsters given the commercial diet containing lucerne meal or a semi-purified diet. In Expt 1, monensin improved feed conversion efficiency and growth performances in the young growing hamsters, but monensin did not affect the hamsters at a later growing stage. In response to monensin the proportion of acetic acid increased and that of propionic acid decreased in the forestomach, whereas the proportion of acetic acid decreased and that of propionic acid increased in the caecum in Expt 2. The hamsters given 135 mg monensin/kg ate less, developed diarrhoea and died. The apparent digestibility of crude protein (nitrogen X 6.25) was improved by monensin but those of dry matter and neutral-detergent fibre (NDF) were decreased in hamsters given the semi-purified diet in Expt 3. Monensin did not appear to have a significant effect on the apparent digestibility of the diet containing lucerne meal. The responses to monensin in hamsters are compared with those in ruminants. PMID:4063298

  2. Alternative solutions to the current situation of oocyte donation in Singapore.

    PubMed

    Heng, Boon Chin

    2006-03-01

    The rising incidence of age-related female infertility in Singapore, coupled with the prohibition on commercialized oocyte donation and egg sharing, has resulted in a severe shortage of donor oocytes. Infertile women are routinely encouraged by fertility doctors here to seek their close relatives and friends as prospective oocyte donors, which does not alleviate the shortage. A number of alternative solutions are discussed. The use of substantial financial remuneration to encourage oocyte donation is rejected as being legally, ethically and morally incompatible with present day Singaporean society. Egg sharing in return for subsidized fertility may have a strong case for ethical justification, but implementation would need amendment of the current legislation in Singapore. Cross- and mirror-exchange oocyte donations face less of a legal challenge in Singapore and also have a strong case for ethical justification. However, special consideration must be given to the unique socio-cultural values of Singaporean society, i.e. traditional Chinese culture. Finally, if no changes are made to restrictive regulations governing oocyte donation in Singapore, and shortage of donor oocytes still persists, then reproductive tourism abroad may be the solution for some patients; referrals by local fertility doctors are unlikely to be allowed in Singapore. PMID:16569312

  3. Structural aspects of oocyte maturation in the blue fox (Alopex lagopus).

    PubMed

    Hyttel, P; Farstad, W; Mondain-Monval, M; Bakke Lajord, K; Smith, A J

    1990-01-01

    Blood samples were taken weekly from seventeen mature blue fox vixens (average age five years), from late anoestrus until pro-oestrus, and then taken daily. The vixens were sacrificed at various stages of oestrus, and oocytes were collected from ovarian follicles by aspiration, and/or from oviducts by flushing. The structural features of oocyte maturation were related to the time of the luteinizing hormone (LH) peak. On days 1-2 after the LH peak the oocyte nucleus migrated from a central to a peripheral position in the ooplasm and assumed a flattened appearance. The cumulus investment expanded simultaneously and ovulation took place around day 2. On days 2-3 the oocyte nuclear envelope broke down, the nucleoli disappeared, the metaphase of the first meiotic division was reached, the Golgi complexes decreased in size, the perivitelline space enlarged, and all junctional contact between cumulus cell projections and oocyte was disrupted. On days 3-5 the first polar body was extruded, the metaphase of the second meiotic division was reached, and the cumulus cells degenerated. On day 5 the release of cortical granule content was occasionally seen, and from day 6 the oocytes showed signs of degeneration. In a few animals deviant oocyte maturation was noticed. PMID:2346225

  4. Predictive value of oocyte morphology in human IVF: a systematic review of the literature

    PubMed Central

    Rienzi, Laura; Vajta, Gábor; Ubaldi, Filippo

    2011-01-01

    BACKGROUND Non-invasive selection of developmentally competent human oocytes may increase the overall efficiency of human assisted reproduction and is regarded as crucial in countries where legal, social or religious factors restrict the production of supernumerary embryos. The purpose of this study was to summarize the predictive value for IVF success of morphological features of the oocyte that can be obtained by light or polarized microscopic investigations. METHODS Studies about oocyte morphology and IVF/ICSI outcomes were identified by using a systematic literature search. RESULTS Fifty relevant articles were identified: 33 analysed a single feature, 9 observed multiple features and investigated the effect of these features individually, 8 summarized the effect of individual features. Investigated structures were the following: meiotic spindle (15 papers), zona pellucida (15 papers), vacuoles or refractile bodies (14 papers), polar body shape (12 papers), oocyte shape (10 papers), dark cytoplasm or diffuse granulation (12 papers), perivitelline space (11 papers), central cytoplasmic granulation (8 papers), cumulus–oocyte complex (6 papers) and cytoplasm viscosity and membrane resistance characteristics (2 papers). None of these features were unanimously evaluated to have prognostic value for further developmental competence of oocytes. CONCLUSIONS No clear tendency in recent publications to a general increase in predictive value of morphological features was found. These contradicting data underline the importance of more intensive and coordinated research to reach a consensus and fully exploit the predictive potential of morphological examination of human oocytes. PMID:20639518

  5. Human Cumulus Cells Molecular Signature in Relation to Oocyte Nuclear Maturity Stage

    PubMed Central

    Ouandaogo, Zamalou Gisèle; Haouzi, Delphine; Assou, Said; Dechaud, Hervé; Kadoch, Issac Jacques; De Vos, John; Hamamah, Samir

    2011-01-01

    The bi-directional communication between the oocyte and the surrounding cumulus cells (CCs) is crucial for the acquisition of oocyte competence. We investigated the transcriptomic profile of human CCs isolated from mature and immature oocytes under stimulated cycle. We used human Genome U133 Plus 2.0 microarrays to perform an extensive analysis of the genes expressed in human CCs obtained from patients undergoing intra-cytoplasmic sperm injection. CC samples were isolated from oocyte at germinal vesicle, stage metaphase I and stage metaphase II. For microarray analysis, we used eight chips for each CC category. Significance analysis of microarray multiclass was used to analyze the microarray data. Validation was performed by RT-qPCR using an independent cohort of CC samples. We identified differentially over-expressed genes between the three CC categories. This study revealed a specific signature of gene expression in CCs issued from MII oocyte compared with germinal vesicle and metaphase I. The CC gene expression profile, which is specific of MII mature oocyte, can be useful as predictors of oocyte quality. PMID:22087263

  6. The apoptotic transcriptome of the human MII oocyte: characterization and age-related changes.

    PubMed

    Santonocito, Manuela; Guglielmino, Maria Rosa; Vento, Marilena; Ragusa, Marco; Barbagallo, Davide; Borzì, Placido; Casciano, Ida; Scollo, Paolo; Romani, Massimo; Tatone, Carla; Purrello, Michele; Di Pietro, Cinzia

    2013-02-01

    Fully competent oocytes represent the final outcome of a highly selective process. The decline of oocyte competence with ageing, coupled to quantitative decrease of ovarian follicles has been well established; on the contrary, its molecular bases are still poorly understood. Through quantitative high throughput PCR, we investigated the role of apoptotic machinery (AM) in this process. To this aim, we determined AM transcriptome in mature MII oocyte pools from women aged more than 38 years (cohort A), and compared to women aged up to 35 years (cohort B). Subsequently, 10 representative AM genes were selected and analyzed in 33 single oocytes (15 from cohort A and 18 from cohort B). These investigations led us to identify: (1) the significant upregulation of proapoptotic genes such us CD40, TNFRSF10A, TNFRSF21 and the downregulation of antiapoptotic genes such as BCL2 and CFLAR in cohort A respect to cohort B; (2) AM transcripts that have not previously been reported in human oocytes (BAG3, CD40, CFLAR, TNFRSF21, TRAF2, TRAF3). Our results demonstrated that during maturation the oocytes from older women selectively accumulate mRNAs that are able to trigger the extrinsic apoptotic pathway. These data contribute to clarify the molecular mechanisms of AM involvement in the natural selection strategy of removing low quality oocytes and preventing unfit or poorly fit embryos. PMID:23179180

  7. Effects of Lactobacillus rhamnosus on zebrafish oocyte maturation: an FTIR imaging and biochemical analysis.

    PubMed

    Giorgini, Elisabetta; Conti, Carla; Ferraris, Paolo; Sabbatini, Simona; Tosi, Giorgio; Rubini, Corrado; Vaccari, Lisa; Gioacchini, Giorgia; Carnevali, Oliana

    2010-12-01

    The aim of this study was to verify the effects of probiotic Lactobacillus rhamnosus on zebrafish oocyte maturation using FPA (focal plane array) FTIR imaging together with specific biochemical assays (SDS-PAGE, real-time PCR and enzymatic assay). Oocyte growth is prevalently due to a vitellogenic process which consists of the hepatic synthesis of vitellogenin and its selective uptake during maturation. The administration of L. rhamnosus IMC 501 for 10 days induced chemical changes to oocyte composition, promoting the maturation process. Some interesting biochemical features, linked to protein secondary structure (amide I band) and to phospholipidic and glucidic patterns, were detailed by vibrational analysis. The spectroscopic results were supported by the early increase of the lysosomal enzyme involved in the final oocyte maturation, the cathepsin L. This enzyme increases during follicle maturation, with the highest levels in class IV oocytes. In treated females, class III oocytes showed higher cathepsin L gene expression and enzymatic activity, with levels comparable to class IV oocytes isolated from controls; this can be related to the proteolytic cleavage of the higher molecular mass yolk protein components, as evidenced by SDS-PAGE. PMID:20936269

  8. MSP Hormonal Control of the Oocyte MAP Kinase Cascade and Reactive Oxygen Species Signaling

    PubMed Central

    Yang, Youfeng; Han, Sung Min; Miller, Michael A.

    2014-01-01

    The MSP domain is a conserved immunoglobulin-like structure that is important for C. elegans reproduction and human motor neuron survival. C. elegans MSPs are the most abundant proteins in sperm, where they function as intracellular cytoskeletal proteins and secreted hormones. Secreted MSPs bind to multiple receptors on oocyte and ovarian sheath cell surfaces to induce oocyte maturation and sheath contraction. MSP binding stimulates oocyte MPK-1 ERK MAP Kinase (MAPK) phosphorylation, but the function and mechanism are not well understood. Here we show that the Shp class protein-tyrosine phosphatase PTP-2 acts in oocytes downstream of sheath/oocyte gap junctions to promote MSP-induced MPK-1 phosphorylation. PTP-2 functions in the oocyte cytoplasm, not at the cell surface to inhibit multiple RasGAPs, resulting in sustained Ras activation. We also provide evidence that MSP promotes production of reactive oxygen species (ROS), which act as second messengers to augment MPK-1 phosphorylation. The Cu/Zn superoxide dismutase SOD-1, an enzyme that catalyzes ROS breakdown in the cytoplasm, inhibits MPK-1 phosphorylation downstream of or in parallel to ptp-2. Our results support the model that MSP triggers PTP-2/Ras activation and ROS production to stimulate MPK-1 activity essential for oocyte maturation. We propose that secreted MSP domains and Cu/Zn superoxide dismutases function antagonistically to control ROS and MAPK signaling. PMID:20380830

  9. Ultrastructural interactions and genotoxicity assay of cerium dioxide nanoparticles on mouse oocytes.

    PubMed

    Courbiere, Blandine; Auffan, Mélanie; Rollais, Raphaël; Tassistro, Virginie; Bonnefoy, Aurélie; Botta, Alain; Rose, Jérôme; Orsière, Thierry; Perrin, Jeanne

    2013-01-01

    Cerium dioxide nanoparticles (C(e)O? ENPs) are on the priority list of nanomaterials requiring evaluation. We performed in vitro assays on mature mouse oocytes incubated with C(e)O? ENPs to study (1) physicochemical biotransformation of ENPs in culture medium; (2) ultrastructural interactions with follicular cells and oocytes using Transmission Electron Microscopy (TEM); (3) genotoxicity of C(e)O? ENPs on follicular cells and oocytes using a comet assay. DNA damage was quantified as Olive Tail Moment. We show that ENPs aggregated, but their crystal structure remained stable in culture medium. TEM showed endocytosis of C(e)O? ENP aggregates in follicular cells. In oocytes, C(e)O? ENP aggregates were only observed around the zona pellucida (ZP). The comet assay revealed significant DNA damage in follicular cells. In oocytes, the comet assay showed a dose-related increase in DNA damage and a significant increase only at the highest concentrations. DNA damage decreased significantly both in follicular cells and in oocytes when an anti-oxidant agent was added in the culture medium. We hypothesise that at low concentrations of C(e)O? ENPs oocytes could be protected against indirect oxidative stress due to a double defence system composed of follicular cells and ZP. PMID:24185910

  10. Effects of Aroclor 1254 on In Vivo Oocyte Maturation in the Mouse

    PubMed Central

    Liu, ShuZhen; Jiang, LiGang; Meng, XiaoQian; Han, XiaoYing; Cheng, Dong; Zhang, TianLiang; Miao, YiLiang

    2014-01-01

    Polychlorinated biphenyls (PCBs) are stable, lipophilic compounds that accumulate in the environment and in the food chain. Though some studies provided evidence that PCBs had adverse effects on reproductive function, most of these results were from in vitro models. Therefore we investigated the effect of Aroclor 1254 (a commercial PCBs mixture) treatments on in vivo maturation and developmental potential of mouse oocytes. In the present study, female ICR mice were treated with different doses (12.5, 25 and 50 mg/kg) of Aroclor 1254 (a commercial PCB mixture) once every 72 hours by intraperitoneal injection for 9 days. After three treatments of Aroclor 1254, the mice were superovulated to collect oocytes one day after the last exposure. The effects of Aroclor 1254 on oocyte maturation, fertilization, and preimplantation embryonic development were investigated. Immunofluorescence-stained oocytes were observed under a confocal microscope to assess the effects of Aroclor 1254 on spindle morphology. Parthenogenic activation and the incidence of cumulus apoptosis in cumulus-oocyte complexes were observed as well. Oocytes exposed to different doses of Aroclor 1254 in vivo were associated with a significant decrease in outgrowth potential, abnormal spindle configurations, and the inhibition of parthenogenetic activation of ovulated oocytes. Furthermore, the incidence of apoptosis in cumulus cells was increased after exposed to Aroclor 1254. These results may provide reference for the treatment of reproductive diseases such as infertility or miscarriage caused by environmental contaminants. PMID:25013911

  11. Functional involvement of Xenopus LIM kinases in progression of oocyte maturation.

    PubMed

    Takahashi, T; Koshimizu, U; Abe, H; Obinata, T; Nakamura, T

    2001-01-15

    LIM kinases (LIMK), including LIMK1 and LIMK2, are unique LIM-family proteins containing a catalytic (kinase) domain. These kinases phosphorylate an actin-depolymerizing factor, cofilin, involved in the regulation of actin-filament dynamics. An unanswered question is the in vivo function of LIMK and how they contribute to development. When we cloned Xenopus homologues of mammalian LIMK, Xlimk1 and Xlimk2, we found that their mRNA and products were abundantly expressed in oocytes. In addition, we obtained evidence for the functional involvement of Xlimk1/2 during oocyte maturation. The microinjection of Xlimk1/2 mRNA into progesterone-treated oocytes significantly inhibited the appearance of a white maturation spot (WMS), an indicator of entry into meiosis. In oocytes lacking a WMS, the organization and/or migration of the microtubule-derived precursor of the meiotic spindle was predominantly affected. We also found that the ectopic expression of Xlimk1/2 clearly prevented dephosphorylation (activation) of Xenopus cofilin (XAC) during oocyte maturation. Furthermore, co-injection of Xlimk1/2 with the constitutively active type of XAC overcame the inhibitory effects by Xlimk1/2, suggesting that XLIMK-induced abnormality in oocyte maturation was mediated by XAC inactivation. Based on these findings, we propose that XLIMK is a putative regulator of cytoskeletal rearrangements during oocyte maturation, and the interaction between XLIMK activity and microtubule dynamics seems highly likely. PMID:11150247

  12. Incorporation of phosphatase inhibitor in culture prompts growth initiation of isolated non-growing oocytes.

    PubMed

    Morohaku, Kanako; Hoshino, Yumi; Sasada, Hiroshi; Sato, Eimei

    2013-01-01

    In vitro folliculogenesis of primordial and early preantral follicles is necessary for increment of reproductive efficiency in domestic animals, humans and endangered species. Recent study in phosphatase and tensin homolog (Pten) -knockout mice has revealed that this phosphatase acts as an inhibitory factor in follicle activation of primordial pool with the resultant inhibition of oocyte growth. To test in vitro effect of a phosphatase inhibitor on growth initiation of isolated non-growing oocytes in neonatal ovaries, we applied a specific inhibitor (bpV (HOpic)) for PTEN in culturing system. Non-growing oocytes isolated from the ovaries of newborn BDF1 (C57BL/6 × DBA/2) pups were divided to four culture groups. Five days after culture, the oocytes in 14 ?mol/l bpV only, 14 ?mol/l bpV plus 100 ng/ml Kit Ligand (KL), and 100 ng/ml KL groups showed significantly (P<0.05) growth (19.3 ± 0.55, 25.8 ± 0.53 and 21.6 ± 0.29 ?m, respectively) compared with that of the control (no additive) (16.9 ± 0.53 ?m). In addition, western blotting in those groups showed enhanced expression of phosphorylated Akt. In conclusion, we clearly demonstrate that isolated non-growing oocytes develop in phosphatase inhibitor, especially to PTEN, incorporated culturing system, and show first as we know that oocytes with zona Pellucidae can be obtained in vitro from isolated non-growing oocytes. PMID:24223714

  13. Promotion of EGF receptor signaling improves the quality of low developmental competence oocytes.

    PubMed

    Sugimura, Satoshi; Ritter, Lesley J; Rose, Ryan D; Thompson, Jeremy G; Smitz, Johan; Mottershead, David G; Gilchrist, Robert B

    2015-07-15

    Oocytes acquire developmental competence with progressive folliculogenesis. Cumulus oocyte complexes (COCs) from small antral follicles have inherent low competence and are poorly responsive to amphiregulin (AREG) which normally mediates oocyte maturation and ovulation. Using low competence porcine COCs, in an in vitro AREG-induced oocyte maturation system, the combined exposure to N(6),2'-O-dibutyryladenosine 3':5' cyclic monophosphate (cAMP) and bone morphogenetic protein 15 (B15) and growth differentiation factor 9 (G9) was necessary to enhance the rate of oocyte meiotic maturation and blastocyst formation. Furthermore, the combination of cAMP+B15+G9 enabled AREG-stimulated cumulus expansion and increased expression of the matrix-related genes HAS2, TNFIPA6 and PTGS2. Additionally, the combination enhanced p-ERK1/2 which is downstream of the EGF receptor. The enhanced nuclear maturation and blastocyst formation rates with the combinational treatment were ablated by an EGF receptor phosphorylation inhibitor. These results indicate that cAMP and oocyte-secreted factors cooperate to promote EGF receptor functionality in developing COCs, representing a key component of the acquisition of oocyte developmental competence. PMID:25981108

  14. Ultrastructural Interactions and Genotoxicity Assay of Cerium Dioxide Nanoparticles on Mouse Oocytes

    PubMed Central

    Courbiere, Blandine; Auffan, Mélanie; Rollais, Raphaël; Tassistro, Virginie; Bonnefoy, Aurélie; Botta, Alain; Rose, Jérôme; Orsière, Thierry; Perrin, Jeanne

    2013-01-01

    Cerium dioxide nanoparticles (CeO2 ENPs) are on the priority list of nanomaterials requiring evaluation. We performed in vitro assays on mature mouse oocytes incubated with CeO2 ENPs to study (1) physicochemical biotransformation of ENPs in culture medium; (2) ultrastructural interactions with follicular cells and oocytes using Transmission Electron Microscopy (TEM); (3) genotoxicity of CeO2 ENPs on follicular cells and oocytes using a comet assay. DNA damage was quantified as Olive Tail Moment. We show that ENPs aggregated, but their crystal structure remained stable in culture medium. TEM showed endocytosis of CeO2 ENP aggregates in follicular cells. In oocytes, CeO2 ENP aggregates were only observed around the zona pellucida (ZP). The comet assay revealed significant DNA damage in follicular cells. In oocytes, the comet assay showed a dose-related increase in DNA damage and a significant increase only at the highest concentrations. DNA damage decreased significantly both in follicular cells and in oocytes when an anti-oxidant agent was added in the culture medium. We hypothesise that at low concentrations of CeO2 ENPs oocytes could be protected against indirect oxidative stress due to a double defence system composed of follicular cells and ZP. PMID:24185910

  15. Lectin from embryos and oocytes of Xenopus laevis. Purification and properties.

    PubMed

    Roberson, M M; Barondes, S H

    1982-07-10

    Soluble extracts of Xenopus laevis blastula stage embryos, oocytes, and adult liver contain lectin activities detected by agglutination of trypsinized, glutaraldehyde-fixed rabbit erythrocytes. Lectin from the embryos and oocytes was purified by affinity chromatography on a column derivatized with melibiose. Trace contaminants were removed either by preparative isoelectric focusing or by gel filtration. Based on its behavior on Sepharose 6B the purified oocyte lectin has an apparent molecular weight of approximately 480,000. On sodium dodecyl sulfate polyacrylamide gel electrophoresis under reducing conditions there were two major bands with molecular weight ranges of about 43,000 and 45,000, with diffuse trails. Since the purified lectin contains about 20% saccharides by weight and since both bands are glycosylated, diffuseness might be due to variable glycosylation. Heterogeneity was indicated by isoelectric focusing in polyacrylamide gels, which showed four protein bands with isoelectric points ranging from 4.4 to 4.9. Lectins from both embryos and oocytes comprised about 1 to 2% of the total soluble protein and could not be distinguished by sodium dodecyl sulfate polyacrylamide gel electrophoresis. However, the specific hemagglutination activity of the purified oocyte lectin was, on the average, 7-fold higher. Levels in crude extracts of liver were 3 orders of magnitude lower than those from oocytes. The hemagglutination activities of the lectins from embryos, oocytes, and adult liver required Ca2+ and were blocked by similar concentrations of both alpha- and beta-galactosides. PMID:7085636

  16. Does women’s age influence zona pellucida birefringence of metaphase ?? oocytes in in-vitro maturation program?

    PubMed Central

    Omidi, Marjan; Khalili, Mohammad Ali; Nahangi, Hossein; Ashourzadeh, Sareh; Rahimipour, Marzieh

    2013-01-01

    Background: In vitro maturation (IVM) is a promising treatment option for certain infertile women. Nowadays, with the aid of PolScope, it has become possible to evaluate zona pellucida (ZP) characteristics as a parameter of oocyte quality. Moreover, quality of oocytes can be influenced by many factors, such as patient’s age. The PolScope system is a non-invasive technique to assess birefringent structures such as the meiotic spindle and ZP in living oocytes. Objective: The aim was to determine the influence of the woman's age on ZP birefringence, a sign of oocyte quality, and morphology of in-vitro matured human oocytes using non-invasive polarized light (PolScope) microscopy. Materials and Methods: ZP birefringence and morphology were determined in 105 retrieved oocytes from 58 women undergoing ICSI in two age groups (?30 years and <30 years). The immature oocytes were selected and after IVM, the quality of metaphase ?? (MII) oocytes was assessed. The oocytes abnormalities were classified as intracytoplasmic and extracytoplasmic abnormalities. Results: Oocyte maturation rates were significantly reduced in ?30 year’s women (56%) in comparison with other age group (80.7%). In addition, the ZP birefringence was significantly higher in MII oocytes in the younger group compared with the older group (76.2% vs. 38.1%; p=0.00). Following morphologic assessment, the rates of oocytes with extracytoplasmic (p=0.02) and both abnormalities (extra- and intracytoplasmic) (p=0.01) were higher in aged versus the younger women. Conclusion: There was a positive relationship between advanced maternal age with decreased ZP birefringence and oocyte morphological quality in in-vitro matured human oocytes. PMID:24639703

  17. Jet penetration of high explosive

    SciTech Connect

    Poulsen, P

    1999-08-11

    It is found that a transition between two flow patterns takes place in thick HE targets. In this case, the jet will initially propagate into the HE at the same rate as into an inert material of the same density. The part of the jet that has stagnated and is flowing nearly co-axially with the incoming jet (but at a much lower speed) is being forced toward the surface of the incoming jet by the pressure of the reaction products but has not as yet made contact. After it makes contact, both axial and perpendicular momentum transfer takes place between the two jet components. After this transition, a new steady state will develop for the propagating jet, with the unperturbed front of the jet propagating at a slower rate than previously. The perturbed front of the jet is still propagating at or near the original rate, having had relatively little axial momentum exchange. However, it has acquired radial momentum and is spreading out as it is propagating; it is therefore becoming less capable of penetrating downstream targets. It is the unperturbed part of the jet that is capable of penetrating downstream targets. A calculational method for predicting this case is presented in this report.

  18. Can serum oestradiol be a predictor of quality of oocytes and embryos, maturation of oocytes and pregnancy rate in ICSI cycles?

    PubMed

    Ozdegirmenci, Ozlem; Dilbaz, Serdar; Cinar, Ozgur; Aydin, Sevim; Beydilli, Gulay; Cakir, Leyla; Guven, Emine Seda Guvendag; Akyol, Mesut; Haberal, Ali

    2011-04-01

    Our aim was to assess the influence of ratios of oestradiol (E2) to either number of follicles ? 14 mm on the day of human chorionic gonadotropin administration (E2/fol) or the number of oocytes retrieved (E2/o) during oocyte pick up and total serum E2 levels on the day of embryo transfer (ETE2) on the outcome of ICSI cycles. The assessed outcomes were number of oocytes retrieved (NRO), number of mature oocytes (NMO), number of fertilised oocytes (NFO), number of transferred embryos (NTE), qualities of oocytes (OQS), qualities of embryos (EQS) and pregnancy rates (PR). Two hundred and twenty-seven ICSI-ET cycles admitted to our IVF clinic during a 2-year period with normal ovarian reserve receiving long luteal GnRH agonist protocol were included. The E2/fol levels correlated positively with NRO (r = 0.202, p = 0.002), NMO (r = 0.199, p = 0.003) and NFO (r = 0.159, p = 0.018). However, we observed negative correlations between E2/o and NMO (r = -0.329, p <0.001), NFO (r = -0.219, p = 0.001), EQ5 (r = -0.203, p = 0.040). Oocyte quality scores were not affected from either E2/fol or E2/o levels. Implantation, clinical and ongoing PRs were comparable between groups categorised due to E2/fol, E2/o and ETE2. It seems that high E2/fol ratio may have beneficial effects on NRO, NMO and NFO while E2/o may adversely affect these parameters. Neither of the E2 levels is associated with pregnancy rates in women with normal ovarian reserve. PMID:20540672

  19. Developmental competence and gene expression of immature oocytes following liquid helium vitrification in bovine.

    PubMed

    Chen, Jun-Yi; Li, Xiao-Xia; Xu, Ya-Kun; Wu, Hua; Zheng, Jun-Jun; Yu, Xue-Li

    2014-12-01

    The objective of this study was to develop an effective ultra-rapid vitrification method and evaluate its effect on maturation, developmental competence and development-related gene expression in bovine immature oocytes. Bovine cumulus oocyte complexes were randomly allocated into three groups: (1) controls, (2) liquid nitrogen vitrification, and (3) liquid helium vitrification. Oocytes were vitrified and then warmed, the percentage of morphologically normal oocytes in liquid helium group (89.0%) was significantly higher (P<0.05) than that of the liquid nitrogen group (81.1%). When the vitrified-thawed oocytes were matured in vitro for 24h, the maturation rate in liquid helium group (50.6%) was higher (P<0.05) than liquid nitrogen group (42.6%). Oocytes of liquid helium vitrification had higher cleavage and blastocyst rates (41.1% and 10.0%) than that of liquid nitrogen vitrification (33.0% and 4.5%; P<0.05) after in vitro fertilization. Moreover, the expression of GDF9 (growth/differentiation factor-9), BAX (apoptosis factor) and ZAR1 (zygote arrest 1) was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) when the vitrified-thawed oocytes were matured 24h. The expression of these genes was altered after vitrification. Expression of GDF9 and BAX in the liquid helium vitrification group was not significantly different from that of the control, however there were significant differences between the liquid nitrogen vitrification group and control. In conclusion, it was feasible to use liquid helium for vitrifying bovine immature oocytes. There existed an association between the compromised developmental competence and the altered expression levels of these genes for the vitrified oocytes. PMID:25307439

  20. Loss of glycogen synthase kinase 3 isoforms during murine oocyte growth induces offspring cardiac dysfunction.

    PubMed

    Monteiro da Rocha, André; Ding, Jun; Slawny, Nicole; Wolf, Amber M; Smith, Gary D

    2015-05-01

    Glycogen synthase kinase-3 (GSK3) is a constitutively active serine threonine kinase with 1) two isoforms (GSK3A and GSK3B) that have unique and overlapping functions, 2) multiple molecular intracellular mechanisms that involve phosphorylation of diverse substrates, and 3) implications in pathogenesis of many diseases. Insulin causes phosphorylation and inactivation of GSK3 and mammalian oocytes have a functional insulin-signaling pathway whereby prolonged elevated insulin during follicle/oocyte development causes GSK3 hyperphosphorylation, reduced GSK3 activity, and altered oocyte chromatin remodeling. Periconceptional diabetes and chronic hyperinsulinemia are associated with congenital malformations and onset of adult diseases of cardiovascular origin. Objectives were to produce transgenic mice with individual or concomitant loss of GSK3A and/or GSK3B and investigate the in vivo role of oocyte GSK3 on fertility, fetal development, and offspring health. Wild-type males bred to females with individual or concomitant loss of oocyte GSK3 isoforms did not have reduced fertility. However, concomitant loss of GSK3A and GSK3B in the oocyte significantly increased neonatal death rate due to congestive heart failure secondary to ventricular hyperplasia. Individual loss of oocyte GSK3A or GSK3B did not induce this lethal phenotype. In conclusion, absence of oocyte GSK3 in the periconceptional period does not alter fertility yet causes offspring cardiac hyperplasia, cardiovascular defects, and significant neonatal death. These results support a developmental mechanism by which periconceptional hyperinsulinemia associated with maternal metabolic syndrome, obesity, and/or diabetes can act on the oocyte and affect offspring cardiovascular development, function, and congenital heart malformation. PMID:25833158

  1. Trout coelomic fluid suitability as Goldfish oocyte extender can be determined by a simple turbidity test.

    PubMed

    Depince, A; Marandel, L; Goardon, L; Le Bail, P-Y; Labbe, C

    2011-06-01

    Regeneration technologies such as androgenesis, intracytoplasmic sperm injection, and nuclear transfer require that handling conditions do not alter oocyte ability to sustain embryo development. One important parameter in the maintenance of oocyte quality in fish is the possibility to prevent oocytes activation during manipulation. In Cyprinid, such activation is known to be delayed when Salmonid coelomic fluid is used as incubation medium. Coelomic fluid however is a biological fluid whose ability to sustain oocyte quality during in vitro incubation may be variable. The purpose of the present work was to explore this variability using Rainbow Trout (Oncorhynchus mykiss) coelomic fluid (TCF) and Goldfish (Carassius auratus) oocytes, and to set up a test which would reflect TCF suitability for Goldfish oocyte incubation. We showed that different TCF induced very different development rates after oocyte incubation for 30 min at 20 °C: at 24h post fertilization (pf) and at hatching, rates ranged between 35% and 110% of the non-incubated controls. When TCF (1 volume) was mixed with tap water (9 volumes), a precipitate developed whose extent was measured by spectrophotometry. This turbidity test proved to be highly correlated to development rates after Goldfish oocyte incubation in TCF (r(2) = 0.83 at hatching, n = 150): TCF with the highest turbidity (> 1.5 absorbance unit at 400 nm) were the ones which altered the most the development rates after incubation (less than 50 % at hatching). This easy and rapid turbidity test can therefore be used as a reliable estimator of TCF suitability for Goldfish oocyte incubation and manipulation. PMID:21356550

  2. Heterologous ovum penetration by human spermatozoa

    Microsoft Academic Search

    J. P. P. Tyler; J. P. Pryor; W. P. Collins

    1981-01-01

    Summary. An evaluation of a method utilizing zona-free hamster ova to test the fertility of human spermatozoa has shown that (i) the induction of superovulation in immature animals provides the most convenient method of obtaining mature ova for study; (ii) motile spermatozoa are best prepared by the technique of layering; (iii) an 18 h incubation at 37\\\\s=deg\\\\C(which is associated with

  3. Adnexal Torsion during Pregnancy after Oocyte In Vitro Maturation and Intracytoplasmic Sperm Injection Cycle

    PubMed Central

    Giulini, Simone; Dante, Giulia; Xella, Susanna; La Marca, Antonio; Marsella, Tiziana; Volpe, Annibale

    2010-01-01

    We report a case of right adnexal torsion during pregnancy after an oocyte in vitro maturation and intracitoplasmic sperm injection cycle in patient with polycystic ovary syndrome. A 31-year-old woman with a typical clinical disorder of polycystic ovarian syndrome was included in an oocyte in vitro maturation program. Right adnexal torsion occurred two days after embryo transfer, and laparoscopy detorsion was successfully performed with preservation of adnexa. The patient had a full-term pregnancy and delivered a healthy infant at 40 weeks of gestation. To our knowledge this is the first report of adnexal torsion after an oocyte in vitro maturation and intracitoplasmic sperm injection program. PMID:20814540

  4. Native yeast telomeres are sufficient to stabilize linear DNA in Xenopus laevis oocytes.

    PubMed

    Schmid, M; Steinbeisser, H; Ascenzioni, F; Trendelenburg, M F; Lipps, H J

    1991-09-30

    We have constructed a linear plasmid in yeast containing the entire bovine papillomavirus genome and tested its physical stability following microinjection into stage VI oocytes of Xenopus laevis. Our results show that unmodified telomeres, in contrast to the yeast-passaged telomeres, drastically affect the stability of the injected linear plasmid. Plasmids carrying unmodified Tetrahymena thermophila telomeric sequences are rapidly degraded in oocytes. When these plasmids are passed through yeast, the telomere ends become modified by the addition of yeast telomeric sequences. These plasmids are stably maintained in X. laevis oocytes, demonstrating that yeast-modified telomeres are sufficient to prevent linear DNA degradation. PMID:1657721

  5. Frontispiece: Labeling Strategy and Signal Broadening Mechanism of Protein NMR Spectroscopy in Xenopus laevis Oocytes.

    PubMed

    Ye, Yansheng; Liu, Xiaoli; Chen, Yanhua; Xu, Guohua; Wu, Qiong; Zhang, Zeting; Yao, Chendie; Liu, Maili; Li, Conggang

    2015-06-01

    NMR Spectroscopy In their Communication on page?8686?ff., C. Li et?al., demonstrate that (19) F labeling is a good first choice for studying globular and disordered proteins in Xenopus oocytes, especially compared with conventional (15) N- or (13) C-methyl enrichment. By using (19) F labeling, they found that, unlike E. coli cells, the viscosity in oocytes is only about 1.2?times that of water and that inhomogeneous broadening contributes 60-70?% to the line width. The labeling strategies and resonance broadening mechanisms in Xenopus oocytes were explored with the goal of expanding the application of this cell type. PMID:26017161

  6. Live birth of twins after IVF of oocytes that were cryopreserved almost 12 years before.

    PubMed

    Quintans, Carlos J; Donaldson, Monica J; Urquiza, M Fernanda; Carretero, Inés; Pasqualini, R Agustín; Horton, Marcos; Pasqualini, R Sergio

    2012-12-01

    A 45-year-old woman received embryos from IVF by intracytoplasmic sperm injection (ICSI) with her own oocytes that were cryopreserved (slow freezing in a low-sodium medium) 11 years and 7 and a half months before, when she was 33 years old. From seven metaphase-II oocytes thawed, five survived, four were fertilized after ICSI and two cleaving embryos were transferred on day 3. A diamniotic dichorionic term pregnancy was achieved, ending with the delivery of two healthy girls. As far as is known, this case represents, to date, the longest storage period of cryopreserved human oocytes resulting in a live birth. PMID:23063815

  7. The Xenopus Oocyte: A Single-Cell Model for Studying Ca2+ Signaling

    PubMed Central

    Lin-Moshier, Yaping; Marchant, Jonathan S.

    2014-01-01

    In the four decades since the Xenopus oocyte was first demonstrated to have the capacity to translate exogenous mRNAs, this system has been exploited for many different experimental purposes. Typically, the oocyte is used either as a “biological test tube” for heterologous expression of proteins without any particular cell biological insight or, alternatively, it is used for applications where cell biology is paramount, such as investigations of the cellular adaptations that power early development. In this article, we discuss the utility of the Xenopus oocyte for studying Ca2+ signaling in both these contexts. PMID:23457336

  8. Amino Acid Correction of Regulatory Volume Decrease Evoked by Hypotonic Stress in Mouse Oocytes In Vitro.

    PubMed

    Pogorelova, M A; Golichenkov, V A; Pogorelova, V N; Panait, A I; Smirnov, A A; Pogorelov, A G

    2015-05-01

    Regulatory volume decrease in response to hypotonic stress is typical of the oocytes and early mouse embryos. Changes in the kinetics of osmotic reaction can be used as a marker of the modulating effect of the incubation medium on transmembrane transport in embryonic cells. Quantitative laser scanning microtomography (QLSM) was used to measure oocyte volume. In this paper, it is shown that addition of 5 ?M glycine, taurine, or GABA, as well as ATP to Dulbecco's medium abolished the regulatory volume decrease in mature mouse oocytes. PMID:26033585

  9. Optimal Information Security Investment with Penetration Testing

    Microsoft Academic Search

    Rainer Böhme; Márk Félegyházi

    2010-01-01

    \\u000a Penetration testing, the deliberate search for potential vulnerabilities in a system by using attack techniques, is a relevant\\u000a tool of information security practitioners. This paper adds penetration testing to the realm of information security investment.\\u000a Penetration testing is modeled as an information gathering option to reduce uncertainty in a discrete time, finite horizon,\\u000a player-versus-nature, weakest-link security game. We prove that

  10. Effects of in vitro oocyte maturation and embryo culture on the expression of glucose transporters, glucose metabolism and insulin signaling genes in rhesus monkey oocytes and preimplantation embryos.

    PubMed

    Zheng, Ping; Vassena, Rita; Latham, Keith E

    2007-06-01

    Glucose plays a fundamental role during oogenesis and embryogenesis, satisfying the metabolic demands of oocytes and embryos, providing for stored energy reserves in the form of glycogen and supporting nucleotide biosynthesis via the pentose phosphate pathway. Glucose also contributes to the production of amino acids, glycosylated proteins and extracellular components. A detailed understanding of the molecular mechanisms that mediate and regulate glucose uptake and metabolism at different stages of oogenesis and preimplantation embryogenesis could greatly benefit the development of improved methods for in vitro oocyte maturation and in vitro embryo production. Although these processes have been examined in a variety of rodent and agricultural species, detailed information has not yet been described for non-human primates. In this study, we examined the expression of the genes encoding glucose transporters, glucose metabolism enzymes and potential regulators of glucose metabolism in rhesus monkey oocytes and embryos. The data reveal stage-specific regulation of expression of specific types of glucose transporters, stage-specific changes in expression of genes related to different pathways of glucose metabolism and temporal changes in the expression of mRNAs related to insulin signaling. Additionally, the data reveal significant differences in expression of some of these genes in cultured embryos as compared with flushed embryos and between oocytes and embryos obtained following different hormonal stimulation and oocyte maturation protocols. PMID:17416905

  11. Testing shaped charges for penetration in coal

    SciTech Connect

    Scheloske, R.F.

    1982-02-16

    Shaped charges have been proposed for an application in underground coal gasification - namely, to produce horizontal holes in deep coal beds to connect the injection and production wells drilled down from the surface. This report describes an experimental technique for determining the penetration of a shaped charge in coal by measuring its penetration in water and allowing for the density difference in the two materials. The validity of the technique has been confirmed by comparing the penetration of a US Army Shillelagh shaped charge in water and in coal. Results of water penetration tests with three other shaped-charge designs are presented.

  12. A transcription assay for EWS oncoproteins in Xenopus oocytes.

    PubMed

    Ng, King Pan; Cheung, Felix; Lee, Kevin A W

    2010-10-01

    Aberrant chromosomal fusion of the Ewing's sarcoma oncogene (EWS) to several different cellular partners produces the Ewing's family of oncoproteins (EWS-fusion-proteins, EFPs) and associated tumors (EFTs). EFPs are potent transcriptional activators, dependent on the N-terminal region of EWS (the EWS-activation-domain, EAD) and this function is thought to be central to EFT oncogenesis and maintenance. Thus EFPs are promising therapeutic targets, but detailed molecular studies will be pivotal for exploring this potential. Such studies have so far largely been restricted to intact mammalian cells while recent evidence has indicated that a mammalian cell-free transcription system may not support bona fide EAD function. Therefore, the lack of manipulatable assays for the EAD presents a significant barrier to progress. Using Xenopus laevis oocytes we describe a plasmid-based micro-injection assay that supports efficient, bona fide EAD transcriptional activity and hence provides a new vehicle for molecular dissection of the EAD. PMID:21204019

  13. Spiral Calcium Wave Propagation and Annihilation in Xenopus laevis Oocytes

    NASA Astrophysics Data System (ADS)

    Lechleiter, James; Girard, Steven; Peralta, Ernest; Clapham, David

    1991-04-01

    Intracellular calcium (Ca2+) is a ubiquitous second messenger. Information is encoded in the magnitude, frequency, and spatial organization of changes in the concentration of cytosolic free Ca2+. Regenerative spiral waves of release of free Ca2+ were observed by confocal microscopy in Xenopus laevis oocytes expressing muscarinic acetylcholine receptor subtypes. This pattern of Ca2+ activity is characteristic of an intracellular milieu that behaves as a regenerative excitable medium. The minimal critical radius for propagation of focal Ca2+ waves (10.4 micrometers) and the effective diffusion constant for the excitation signal (2.3 x 10-6 square centimeters per second) were estimated from measurements of velocity and curvature of circular wavefronts expanding from foci. By modeling Ca2+ release with cellular automata, the absolute refractory period for Ca2+ stores (4.7 seconds) was determined. Other phenomena expected of an excitable medium, such as wave propagation of undiminished amplitude and annihilation of colliding wavefronts, were observed.

  14. Instability of a penetrating blade

    NASA Astrophysics Data System (ADS)

    Bigoni, D.; Bosi, F.; Dal Corso, F.; Misseroni, D.

    2014-03-01

    Application of a dead compressive load at the free end of an elastic rod (the ‘blade') induces its penetration into a sliding sleeve ending with a linear elastic spring. Bifurcation and stability analysis of this simple elastic system shows a variety of unexpected behaviors: (i) an increase of buckling load at decreasing of elastic stiffness; (ii) a finite number of buckling loads for a system with infinite degrees of freedom (leading to a non-standard Sturm-Liouville problem); (iii) more than one bifurcation load associated to each bifurcation mode; (iv) a restabilization of the straight configuration after the second bifurcation load associated to the first instability mode; (v) the presence of an Eshelby-like (or configurational) force, deeply influencing stability. Only the first of these behaviors was previously known, the second and third ones disprove common beliefs, the fourth highlights a sort of ‘island of instability', and the last one shows surprising phenomena and effects on stability.

  15. The development of Schistosoma haematobium in the hamster.

    PubMed

    Ghandour, A M

    1978-06-01

    The in vivo development of Schistosoma haematobium in the hamster was studied. Six stages of development were distinguished on the basis of morphological and histochemical criteria. Schistosomula reached the lung (stage 1) on day three post-infection, with maximum concentrations on day nine. Gut formation occurred in the second stage at day 18. In stage 3 'Organogeny' (day 24) males developed one testis and females a narrow uterus. Pairing and the development of males with sperm-containing testes and females with an ovary characterize stage 4 (day 28). In stage 5 (day 53) vitelline follicles begin to develop in the females. The final stage, oviposition, occurred on days 61-63 and was characterized by the appearance of fully developed eggs in the uterus. PMID:666393

  16. An NSF rotator's perspective: view from inside the hamster wheel

    NASA Astrophysics Data System (ADS)

    White, Gary

    2015-03-01

    Duncan McBride served as my unofficial mentor during my time at NSF as a ``rotator'' (or, in NSF-speak, an IPA, short for an Intergovernmental Personnel Act assignee), from fall 2012 through summer of 2013. A rotator's main job is to help keep the wheels of the grant submission process turning, shepherding individual proposal jackets through the submission cycle. While most proposals are eventually ``Declined'' it is the few that are funded that evoke the most vivid memories of my time there. I hope to relay a little bit about what that was like on a daily basis, to give one hamster's take on the machinations of the NSF machine, and testify to Duncan McBride's critical role in establishing physics as the leader in disciplinary based educational research (DBER). It was a heady experience in many ways, despite the sheer girth of proposal jackets to be processed and the uncertain footing upon which federal employees tread these days.

  17. Uptake of indocyanine green by hamster sebaceous glands

    NASA Astrophysics Data System (ADS)

    McMillan, Kathleen; Lo, Kai-Ming; Wang, Zhi

    2001-05-01

    Photothermal injury to the sebaceous glands is a potential curative treatment for the common skin disease acne vulgaris. Accumulation of the exogenous chromophore indocyanine green in the sebaceous glands may be accomplished using an emulsion or liposomal formulation applied to the skin surface. An emulsion containing 0.09% by weight indocyanine green (ICG) was applied to the epidermis of hamster ears ex vivo and the flank organ in vivo. Fluorescence microscopy demonstrated selective accumulation of ICG in the underlying sebaceous glands. The concentration of ICG that may be expected to accumulate in sebaceous glands of humans was then estimated on the basis of the gland size and orifice area, for the case of topical application of a more concentrated 1% ICG liposomal formulation. Monte Carlo modeling and heat transfer calculations showed that the sebaceous glands containing the exogenous chromophore may be selectively damaged by pulsed 810 nm laser radiation in conjunction with cryogen spray cooling.

  18. A magnetic field effect on learning in male golden hamsters.

    PubMed

    ?opuch, Sylwia

    2009-05-01

    The aim of this experiment was to investigate the influence of repeated exposure to 10, 20, 30 or 40 Hz magnetic fields at 0.1T on the learning of male golden hamsters in a Skinner box, in which the animals learned to press a lever to receive a food reward. The latency of the first response was not affected by exposure to the magnetic fields used in this experiment. No significant field-dependent effects on the performance of the task were observed in males exposed to 10 and 20 Hz magnetic fields at 0.1T. However, exposure significantly improved the learning of the task in animals exposed to 30 and 40 Hz magnetic fields at 0.1T. PMID:19150395

  19. Repeated exposure to acetaldehyde vapor. Studies in Syrian golden hamsters.

    PubMed

    Kruysse, A; Feron, V J; Til, H P

    1975-09-01

    The subacute inhalation toxicity of acetaldehyde was examined with four groups of 20 hamsters each, exposed repeatedly to acetaldehyde vapor at concentrations of 0, 390, 1,340, and 4,560 ppm (six hr day, five days/week) for a 90-day period. The highest level induced growth retardation, ocular and nasal irritation, increased numbers of erythrocytes, increased weights of heart and kidneys, and severe histopathological changes in the respiratory tract that mainly consisted of necrosis, inflammatory changes, and hyper- and metaplasia of the epithelium. The upper segments of the respiratory tract were much more severely injured than the lower parts. At 1,340 ppm treatment-releated changes included increased kidney weights in males and slight hyper- and metaplastic changes of the tracheal epithelium; 390 ppm was considered a no toxic effect level. PMID:1164047

  20. Survival and yields of chromosome aberrations in hamster and human lung cells irradiated by alpha particles

    SciTech Connect

    Simmons, J.A.; Cohn, P.; Min, T. [Univ. of Westminster, London (United Kingdom)

    1996-02-01

    The effects of {alpha}-particle irradiation on hamster and human lung cells have been studied. In both cases two end points were taken, cell death and the induction of chromosome aberrations. The hamster cells were common stock V79 cells; the human ones were freshly derived from fetal material. For both types of cells, the survival curves could be described by straight lines in the conventional exponential plot, with values of D{sub 0} of 0.78 and 0.37 Gy for the hamster and human cells, respectively. The rate of induction of chromosome aberrations could also be described by straight lines with slopes of 0.30 and 0.62 aberration per cell per gray. Thus, for this second end point also, it appears that human cells are twice as sensitive to the effects of {alpha}-particle irradiation as hamster cells. 30 refs., 3 figs., 2 tabs.