Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Morula”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources
PubMed2004

[Cryopreservation of mouse morula and blastocysts by vitrification].

OBJECTIVE: To compare the survival and developmental potential of mouse morula, early blastocysts and blastocysts cryopreserved by vitrification. METHODS: One hundred and forty-two mouse morula, 135 early blastocysts and 148 blastocysts were cryopreserved by 6 mol/L ethylene glycol and 1 mol/L sucrose vitrification solutions. The survival rates and blastocysts hatching rates after thawing were observed. RESULTS: The survival rates of morula, early blastocysts and blastocysts groups were 88.0%, 73.3%, and 60.1% respectively. The blastocyst hatching rates were 73.9%, 61.5%, and 49.3% respectively. Both the survival rates and blastocyst hatching rates in morula group were higher than those in early blastocysts group (P < 0.05), and they were higher in early blastocysts group than in blastocysts group (P < 0.05). CONCLUSIONS: In these three embryo stages, the survival and developmental potential of mouse morula cryopreserved by vitrification are better than those of early blastocysts and blastocysts. Morula is likely the most feasible stage for embryo vitrification.

Animals↗
PubMed1990

The survival of whole and bisected rabbit morulae after cryopreservation by the vitrification method.

The survival of whole and bisected rabbit morulae cryopreserved by the vitrification method was investigated. The embryos were loaded in a column of vitrification solution (VS, a mixture of 25% glycerol and 25% 1, 2-propanediol in PBS+16% calf serum), which was located between two columns of 1 M sucrose solution in a plastic straw. The embryos were frozen by being plunged into liquid nitrogen and thawed in a water bath at 20 degrees C. Two methods of loading embryos into straws were used: the single and double column vitrification solution methods. The embryonic survival rates between these two methods were compared. Seventy-one (86.6%) out of 82 morulae vitrified in double column straws developed into the blastocyst stage in vitro. Eleven (18.3%) live fetuses were obtained after the transfer of 60 frozen-thawed morulae to four recipients. By contrast, the survival rate (36.5%, 27 74 ) of embryos vitrified in the single column straws was significantly lower (P<0.05). The vitrification solution of the single column straws became opaque, indicating ice-crystal formation, upon thawing in 5 of 11 straws, which was assumed to have damaged the embryos. More than 80% (29 36 ) of the bisected morulae frozen and thawed in the double column straws developed to the blastocyst stage in vitro when cryoprotectant was diluted stepwise with 1 M and 0.25 M sucrose solution. When the cryoprotectant was removed by one-step dilution with 1 M sucrose solution, swelling in blastomeres was observed and the development rate of the recovered embryos decreased (45.8%, 11 24 ). These results indicate that the vitrification method employed in our experiment is not only efficient for the cryopreservation of rabbit morulae, but it can also be used for the preservation of bisected rabbit morulae, which had not been successful using previous methods.

Journal Article↗
PubMed1995

Effect of human leukemia inhibitory factor on in vitro development of IVF-derived bovine morulae and blastocysts.

This study was conducted to investigate whether human leukemia inhibitory factor (hLIF) improves the subsequent development of IVF-derived bovine morulae and blastocysts. To obtain IVF-derived bovine morulae, ova were matured and fertilized in vitro and cultured in 0.5 ml of synthetic oviduct fluid (SOF) medium supplemented with 10% human serum (HS) for 5 d at 39 degrees C under a gas atmosphere of 5% CO(2), 5% O(2), 90% N(2). Morulae and early blastocysts at Day 5 of culture were cultured in 0.5 ml of SOF medium with or without 5000 U/ml recombinant hLIF for 2 or 3 d (2 groups). To investigate the effect of addition of hLIF on the subsequent development of morulae, SOF medium was supplemented with 8 mg/ml BSA instead of HS. To test whether hLIF affects the subsequent development of IVF-derived bovine blastocysts, only good blastocysts that developed from SOF medium with or without hLIF at Days 7 and 8 of culture were frozen by a conventinal slow freezing method and again cultured in SOF medium with or without the addition of hLIF for 3 d after thawing (4 groups). Survival of frozen-thawed bovine embryos was evaluated for re-expansion and hatching of blastocysts during 3 d of culture. There was no significant difference in the developmental rate of Day 5 embryos to blastocysts between those cultured with (47.8%) and without (47.6%) addition of hLIF. However, the addition of hLIF before freezing significantly increased the hatching rate of IVF-derived bovine morulae (P < 0.05), whereas addition of hLIF after thawing did not increase the subsequent development of blastocysts. These results suggest that hLIF added at the Day 5 morula stage may contribute to bovine embryonic development through the hatching process.

Journal Article↗
PubMed1998

Superovulation of rabbits with FSH alters in vivo development of vitrified morulae.

Morulae were flushed from the oviducts and uteri of New Zealand White (NZW) rabbits superovulated with either 6 (3 d) or 8 (4 d) injections of FSH and from non-superovulated controls. The percentages of embryos recovered from 4 d (100%, n = 8) donors was significantly higher (P < 0.01) than that of 3 d (76%, n = 16) and control (87%, n = 22) donors. Overall, fertilization rates were significantly lower for the 3 d embryos (P < 0.01). Most (86 to 90%) morulae were morphologically suitable for vitrification in an ethylene glycol-based solution. Following storage in liquid nitrogen, morulae were rapidly thawed and transferred to the uteri of pseudopregnant recipients. The total number of kits born for the 3 d, 4 d, and control groups was 40, 61 and 48, respectively. The percentage of live kits from morulae transferred was significantly lower for the 3 d (20%, n = 201) than either the 4 d (36%, n = 169; P < 0.01) or the control (31%, n = 157; P < 0.05) group. The mean number of kits born/recipient for the 3 d (2.4 +/- 2.9), 4 d (4.7 +/- 3.5), and control (3.0 +/- 2.2) protocols did not differ (P > 0.05). The estimated overall efficiency of producing kits based on normal morulae collected for control and 4 d groups, however, was nearly two-fold that for females given 6 FSH treatments. We conclude that the 4 d FSH superovulation regimen enhances the efficiency of rabbit reproductive biotechnology after embryo cryopreservation. These findings have important implications for rabbit colony management using embryo cryopreservation.

Animals↗
PubMed1996

Synergistic effect of alanine and glycine on bovine embryos cultured in a chemically defined medium and amino acid uptake by vitro-produced bovine morulae and blastocysts.

The effect of glycine and alanine on the development of 2- to 4-cell bovine embryos, and amino acid uptake by bovine morulae and blastocysts, were examined through the use of a chemically defined medium. Bovine embryos at 2- to 4-cell stages were prepared by in vitro maturation and fertilization and cultured in a synthetic oviduct fluid medium (SOFM) containing polyvinyl alcohol (PVA) instead of BSA in order to examine the effect of amino acids. Morulae or blastocysts obtained from culture in SOFM containing BSA were cultured for 10 h in SOFM containing PVA to determine amino acid uptake. The combination of essential and nonessential amino acids with or without glutamine improved development to the blastocyst stage over that observed in the control (34% or 32% vs. 19%, respectively; p < 0.05). The optimal supplemental concentrations were 5 mM for alanine and 10 mM for glycine. At these concentrations, development to blastocysts was enhanced by the addition of alanine or glycine independently (35% or 36% vs. 26%, respectively; p < 0.05); the combined addition of alanine and glycine greatly (p < 0.01) improved proportions of blastocysts (45% vs. 26%) and hatched blastocysts (10% vs. 2%) compared to those obtained in the control. Addition of glycine with or without alanine to culture medium significantly increased cell number per blastocyst over that in the control (137 +/- 5 or 131 +/- 5 vs. 106 +/- 4, respectively; p < 0.01). Bovine morulae and blastocysts depleted aspartate, serine, and glutamate at a highly significant rate (p < 0.001) and arginine at a significant rate (p < 0.05), and produced alanine at a highly significant rate (p < 0.001) when cultured in medium containing 20 essential and nonessential amino acids. Serine, asparagine, glycine, alanine, and glutamine were highly (p < 0.001) produced by bovine morulae and blastocysts cultured in a medium containing essential amino acids without glutamine. These results indicate that alanine and glycine in a defined medium synergistically improve development of in vitro-produced bovine embryos, and also that bovine morulae and blastocysts prefer aspartate, glutamate, serine, and arginine and produce glutamine and several nonessential amino acids (serine, asparagine, alanine, and glycine).

Alanine↗
PubMed1998

Antibodies with the cell-type specificity to the morula cells of the solitary ascidians Styela rustica and Boltenia echinata.

The separation of the blood cells of Styela rustica (Styelidae, Stolidobranchiae) in discontinuous Percoll gradient showed 4 fractions. The 4th and bottom most fraction contained 90-100% of morula cells. The protein composition of the morula cell fraction revealed on SDS-PAGE showed two major proteins with m.w. 47 and 26 kDa. These proteins were heavily positively charged. Polyclonal antiserums against these proteins were raised. Each antiserum reacted with both proteins only in morula cells on the blot after SDS-PAGE and stained the proper protein without crossreaction on the blot after AU-PAGE. The only type of cells stained with antibodies in circulating blood, in the tunic and on the tunic wound surface in paraffin sections of another species Boltenia echinata (Pyuridae, Stolidobranchiae) were morula cells. The morula-type specific antibodies obtained recognized major positively charged proteins which were apparently structural substrates for the phenoloxidase tanning.

Animals↗
PubMed1984

Production of monozygotic mouse twins from microsurgically bisected morulae.

Mouse monozygotic twins were produced by bisection of the compacted morulae and transfer of the pairs of half-embryos after culture in vitro. The compacted morulae (about 16 cells) were microsurgically bisected, using a fine glass needle attached to a micromanipulator, without any supporting micro-instruments, after pretreatment for zona-softening and decompaction. About 80% of the morulae were bisected without visible cell damage. After 20 h in culture, the half-embryos were classified morphologically as eu-blastocysts, pseudo-blastocysts, or trophectodermal vesicles or non-integrated forms. After culture of 131 pairs of bisected morulae, 75 (57.3%) pairs of eu-blastocysts, 20 (15.3%) pairs comprising a eu-blastocyst and pseudo-blastocyst, and 9 (6.9%) pairs of pseudo-blastocysts, were obtained. The pseudo-blastocysts were considered to be derived from half-morulae in which some blastomeres were destroyed or dissociated as a result of micromanipulation. From 30 pairs of eu-blastocysts transferred to 21 recipients, 5 twin fetuses on Day 17 (18 pairs/9 recipients) and 3 twin male young (12 pairs/12 recipients) were obtained. Survival rate of the twin-embryo pairs was 27.8% at autopsy and 25.0% at term. None of the 20 pairs of pseudo-blastocysts transferred to 10 recipients gave rise to normal conceptuses.

Animals↗
PubMed1982

Protection of non-cellular investments of rabbit morulae stored at--196 degrees C.

The non-cellular investments were damaged in only 2.8% of rabbit morulae frozen/ thawed in plastic straws. Similar results (4.8%) were obtained with glass ampoules only when morulae were slowly frozen and slowly thawed in siliconized ampoules. Freezing/thawing by other methods and the use of untreated ampoules resulted in high incidence of embryos with damaged investments (41-61%). Morulae frozen/thawed by a method allowing an almost complete elimination of investment injury displayed high survival when slowly frozen and rapidly thawed (90.7%) while slow freezing and slow thawing decreased survival (74.5%). Morulae subjected to rapid freezing were for the first time successfully stored at--196 degrees C. After rapid thawing 59.6% morulae survived. The mechanism of damage to the non-cellular investments of rabbit embryos is discussed.

Animals↗
PubMed1993

Effect of growth factors on morula and blastocyst development of in vitro matured and in vitro fertilized bovine oocytes.

Growth factors were studied as a means of increasing the development of in vitro matured (IVM) and in vitro fertilized (IVF) oocytes into morulae or blastocysts. Cell numbers of blastocysts were also counted. In Experiment 1, 2- to 8-cell embryos derived from bovine IVM/IVF oocytes were randomly allotted to one of 3 culture groups: a) synthetic oviduct fluid (SOF); b) SOF + 10 ng/ml epidermal growth factor (EGF); or c) SOF + 100 ng/ml EGF; all 3 culture media contained 10% fetal bovine serum. Culture resulted in 12%, 23% and 14% (P>0.05), respectively, developing into morulae and blastocysts. In Experiment 2, 5 ng/ml of transforming growth factor B (1) (TGF B (1)) added to CR(1aa) medium containing BSA increased the percentage of blastocysts to 56% vs 40% for the control (P<0.05). In Experiment 3, EGF and TGF B(1), added singly and in combination to CR(1aa) did not produce a synergistic effect. More embryos developed into morulae and blastocysts (45%) in a bovine oviduct epithelial co-culture than in any other treatment except in CR(1aa) + EGF (34%; P>0.05). In Experiment 4, 0, 1 and 5 ng/ml of platelet derived growth factor (PDGF) added to CR(1aa) yielded 39%, 70% and 52% morulae and blastocysts, respectively (P<0.05). Cell number was not increased, indicating that growth factors can increase the proportion of embryos that develop into morulae and blastocysts without an increase in the cell number.

Journal Article↗
PubMed1994

Splitting of porcine embryos at the four-cell or morula stage.

Porcine embryos obtained from estrus-induced prepuberal gilts were split at the 4-cell and morula stage. The in vitro development of the demi-embryos was compared with that of intact control embryos. The intact control embryos developed according to expectation. The in vitro survival of the demi-embryos was inferior to that of the respective controls. The splitting of 4-cell embryos was easier to accomplish and more efficient than the splitting of morulae. The in vitro development of the 4-cell embryos was also slightly better, although this difference was not significant. In vitro development of demi-embryos originating from morulae split at room temperature was slightly although nonsignificantly inferior to that of demi-embryos from morulae split on a warming stage at 37 degrees C. Between 14 and 18 demi-embryos were transferred to synchronous recipient gilts after 24 to 48 h of culture. Of 3 gilts receiving split 4-cell embryos, 1 gilt aborted 2 normal fetuses on Day 90 of pregnancy and 1 carried a single piglet to term. Of the 4 gilts receiving split morulae, 1 gilt had 4 normal and 3 degenerated fetuses upon slaughter on Day 35 of pregnancy.

Journal Article↗
PubMed1995

In vitro culture of goat morulae to blastocysts before freezing.

The results of transfer of frozen-thawed caprine embryos that were collected either as blastocysts or morulae and cultured to the blastocyst stage prior to freezing were compared. After thawing, the embryos collected as blastocysts appeared to be of marginally better quality than those that had been cultured from morulae (89 vs 72% rated as good; P > 0.05). The transfer of 24 frozen-thawed embryos collected as blastocysts to 12 recipients resulted in a pregnancy rate of 83% (10/12) and an embryo survival rate of 67%. Corresponding results for frozen-thawed blastocysts that had been cultured from morulae and were transferred to 11 recipients were 54% (6/11) and 41%, respectively. Since an earlier investigation had shown that the transfer of frozen caprine morulae yields very poor results, in our laboratory all morulae are now cultured to the blastocyst stage before being cryopreserved.

Journal Article↗
PubMed1976

Nucleotides in embryos in the stages of morula, gastrula, and neurula.

Levels of nucleotides and sugar nucleotides in embryos of Bufo arenarum at the stages of morula, gastrula, and neurula have been measured. The total amounts of purine nucleoside diphosphates decreased from morula to gastrula, but increased sharply from gastrula to neurula. The levels of ADP followed this pattern, but those of GDP did not change significantly through the three stages. Purine nucleoside triphosphate levels, which had increased immediately after fertilization, remained almost constant through morula, gastrula, and neurula. As with the purine nucleoside diphosphates, the adenine nucleotide decreased from morula to gastrula, and increased from gastrula to neurula. In contrast, the level of GTP showed a sharp maximum at gastrula. The total pyrimidine nucleoside triphosphate did not change significantly from morula through neurula. As in previous stages of development, only uridine sugar nucleotides were detected. A sharp increase of the galactosyl ester of nucleotides was found at gastrula.

Adenosine Diphosphate↗
PubMed1996

Differences on post-thawing survival between ovine morulae and blastocysts cryopreserved with ethylene glycol or glycerol.

Embryos were collected on Days 5 and 6 after breeding to investigate the effectiveness of ethylene glycol (ETG) and glycerol (GLY) as cryoprotectants of sheep morulae and blastocysts and to determine their optimum stage of development for cryopreservation. Only excellent (grade 1) and good (grade 2) embryos (196 morulae and 188 blastocysts) were incubated in increasing concentrations of GLY or ETG and submitted to a slow-freezing and quick-thawing procedure. Both cryoprotectants were removed using 0.25 M sucrose solution, and then embryos were cultured or transferred to determine their viability. Freezing medium containing ETG yielded higher in vitro survival rates (P < 0.01) than medium containing GLY (64.6% vs 16.0%); the difference between cryoprotectants was greater when morulae were used (57.9% vs 4.2%, P < 0.005) as compared with blastocysts (70.4% vs 21.5%, P < 0.05). There was a strong interaction between type of cryoprotectant and embryo stage (P < 0.005). After transfer of morphologically viable embryos, the in vivo development rate of embryos frozen with ETG was also higher than that of embryos frozen with GLY (45.5% vs 27.7%, P < 0.05). There were no significant differences in the number of lambs born among procedures and embryo stage, though the lowest lambing rate was obtained with morulae frozen with GLY (21.4%). Similar lambing rates were produced when blastocysts were frozen with either GLY or ETG (36.6% vs 43.0%). The best embryo survival after thawing was observed when blastocysts were frozen with ETG as cryoprotectant.

Animals↗
PubMed2005

Cryopreserved morulae can be used to efficiently generate germline-transmitting chimeras by blastocyst injection.

The production of chimeric mice is a complex process, requiring the careful coordination of tissue culture cell growth, production of a large number (30-75) of competent blastocysts and the availability of appropriately timed pseudo pregnant female mice. Failure at any of these steps can impinge upon the rapid production of chimeras. One potential improvement for the efficient generation of chimeric mice would be the utilization of cryopreserved embryos suitable for injection. C57Bl/6 morulae were frozen using a standard 2-step protocol with ethylene glycol as the cryopreservation agent. We determined that cryopreserved morulae could thaw, culture to blastocyst stage in KSOM media and survive injection at rates equivalent to control embryos. Cryopreserved morulae were also equivalent to controls at all later stages in the process of production of chimeric mice, including birth rate, percentage chimerism of resulting animals and ability to produce germline progeny. Hence, cryopreservation of morulae for blastocyst injection is a suitable option to enhance the efficiency of chimeric mouse generation.

Animals↗
PubMed1988

Temporally specific involvement of cell surface beta-1,4 galactosyltransferase during mouse embryo morula compaction.

Cell surface beta-1,4 galactosyltransferase (GalTase) is shown to mediate intercellular adhesions between embryonal carcinoma (EC) cells and specifically during late morula compaction in the preimplantation mouse embryo. Monospecific anti-GalTase IgG raised against affinity-purified bovine beta-1,4 GalTase recognizes F9 EC cell GalTase as judged by immunoprecipitation and inhibition of GalTase activity, as well as by immunoprecipitation of a single 52 kd metabolically labeled membrane protein. Anti-GalTase IgG inhibits cell adhesions between EC cells, dissociates compacted mouse morulae, and inhibits blastocyst formation. Anti-GalTase IgG specifically inhibits cell adhesions during late morula compaction, coincident with a peak of surface GalTase activity as determined by direct enzyme assay. On EC cells, GalTase activity can be proteolytically released from intact cells, and is localized by indirect immunofluorescence to areas of intercellular contact, consistent with its proposed role in cell adhesion. Beta-1,4 GalTase is the first cell adhesion molecule identified that participates during late morula compaction, subsequent to uvomorulin function.

Animals↗
PubMed2006

Embryonic stem cells from morula.

It has been shown that it is possible to establish human embryonic stem cell (hESC) lines from morula. Details of the aforementioned injection method of morula under blastocyst are described in this chapter. This chapter also discloses the application of simultaneous staining for two markers, TRA-2-39 and Oct-4, for characteristics of nondifferentiated hESC derived from morula and gives a method. Technical approaches of freezing morula-derived hESC are discussed.

Blastomeres↗
PubMed2002

Impact of adding 5.5 mM glucose to SOF medium on the development, metabolism and quality of in vitro produced bovine embryos from the morula to the blastocyst stage.

Although toxic for early stages of embryo development, glucose is a physiological metabolic substrate at the morula and blastocyst stages. We evaluated the effect of adding 5.5 mM glucose from the morula stage on bovine blastocyst development and quality. In vitro matured and fertilised bovine oocytes were cultured in modified Synthetic Oviduct Fluid medium containing 5% fetal calf serum, but without added glucose, up to day 5 post-insemination (pi). Morulae were selected and further cultured in the presence or absence of 5.5 mM glucose. Blastocyst and hatched blastocyst rates were recorded. Oxygen, glucose and pyruvate uptakes as well as lactate release were evaluated. The quality of the resulting blastocysts was evaluated by the cell allocation to the inner cell mass (ICM) and trophectoderm (TE) and by the apoptotic index. Adding glucose increased the blastocyst rate at day 8 pi (80% vs 65%) but had no impact on hatching rate (25% vs 28%). A 22% decrease in oxygen uptake was observed in the presence of glucose, concomitant with an increase in lactate release, although no change was observed in pyruvate uptake. A slight decrease in blastocyst cell number was observed at day 7 in the presence of glucose while neither the ICM/TE cell ratio nor the apoptotic index were affected. In conclusion, adding 5.5 mM glucose from the morula stage has a limited impact on blastocyst rate and quality although important modifications were observed in embryo metabolism. It remains to be determined whether those modifications could influence embryo viability after transfer.

Animals↗
PubMed1987

In vitro exposure of bovine morulae to Ureaplasma diversum.

Ureaplasma diversum has been associated with infertility in the cow experimentally and in naturally occurring cases. However, the pathogenic mechanism is undetermined. The purpose of this study was to determine whether ureaplasmas are pathogenic for bovine morulae in vitro. Twenty-one morulae were recovered from three superovulated, mature, Holstein cows six or seven days postestrus. The embryos were divided into three groups (A,B,C) and incubated for 16 hours at 37 degrees C in humidified air with 10% CO2. Group A was incubated in embryo culture medium alone, Group B was incubated in culture medium with sterile ureaplasma broth added and Group C was incubated in culture medium containing 1.7 X 10(6) colony forming units Ureaplasma diversum strain 2312. After incubation, the morulae were examined using an electron microscope. Structures morphologically identical to U. diversum were present on the outer surface of the zonae pellucidae of all the morulae exposed to the organism and none were present on the unexposed control embryos. No other morphological differences were observed in either the ureaplasma-exposed embryos or the two groups of control embryos. Ureaplasma diversum was isolated from three of the five embryos incubated in culture medium with sterile ureaplasma broth added. These three embryos were recovered from one donor cow which cultured positive for U. diversum from the vulva and flush fluid. This finding suggests that the contaminating organisms entered the embryo culture wells either in the embryo collection medium or attached to the embryos.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗