Oocytes in Biological News

Universitat Autonoma de Barcelona researchers first to clone mice in Spain

... order to clone the animals, researchers collected oocytes and surrounding cumulus cells from several female ... The chromosomes were extracted from each of the oocytes and substituted with a cell from the cumulus by cytoplasm injection. Once the oocytes had been reconstructed, they were activated by ...

Animal eggs not suitable substitutes to produce stem cells

... Mary Ann Liebert, Inc., demonstrates that animal oocytes lack the capacity to fully reprogram adult human ... compared the reprogramming of human cells using oocytes obtained from cows, rabbits, and humans. They ... The ability to reprogram human cells using oocytes would enable the production of patient-specific ...

December 2008 highlights from Biology of Reproduction

... ovarian development establishes the population of oocytes and follicles and instigates evelopment of a ... fail to form, the result is oocyte demise, yet oocytes are also essential for follicular development. ... appear to form in Sohlh2 -null ovaries, the oocytes are rapidly lost and follicles do not develop to ...

Stowers Institute's Hawley Lab identifies factors responsible for restart of meiotic cycle

... work in concert to restart the meiotic cycle of oocytes following a natural period of dormancy. The ... of female meiosis. The cells that will become oocytes in human females develop during fetal development ... actual process of meiosis before birth, but the oocytes remain in a suspended state until the female ...

Ovarian transplantation: New technique gives greatly improved results in this delicate operation

... with fluorescent microscopy to determine the loss or preservation of oocytes in fresh and frozen ovarian tissue of 15 young women undergoing cancer ... by classical slow freezing methods. "We found that 91.9% of the fresh oocytes were viable compared with 88.9% of those vitrified. However, slow freezing ...

A unique arrangement for egg cell division

... spindles are found in all dividing cells. What is special about oocytes is that they lack specialised spindle-forming organelles, called ... outside of the egg. For a long time we did not understand how mammalian oocytes could assemble a bipolar spindle without such centrosomes. Tracking ...

Stem cell research: From molecular physiology to therapeutic applications

... reliably used to fulfill the promise of stem cell therapy in regenerative medicine. Dr. Lin Liu's group found that pES cells generated from immature oocytes in mice exhibit pluripotency resembling fES cells, as evidenced by similarly high chimera production and germline transmission. Thus, immature eggs ...

Ovarian transplantation: First baby is born after a new technique

... of eggs we could, and carry out an IVF procedure on this patient. "Six months after the operation, we transferred two blastocysts. A total of 22 oocytes were retrieved and produced 16 embryos, which in turn produced seven blastocysts. Unfortunately the first time round this patient developed an ...

Who goes abroad for fertility treatment and why?

... looked in more detail at the situation in his own country. 16 out of the 18 Belgian reproductive medicine centres which were licensed to handle oocytes and create embryos were surveyed on the nationality of foreign patients coming for treatment between 2000 and 2007, as well as on the type of ...

ESHRE launches international study of polar body screening

... data at ESHRE 2010 in Rome and to start the RCT with the involvement of at least six centres in different European countries later the same year. oocytes to be used in the pilot phase will be obtained from volunteer patients who have given consent for their use in this study. There will be no age ...

CSHL scientists discover a new way in which epigenetic information is inherited

... remains to be seen whether this mechanism of epigenetic inheritance is found in organisms besides fruit flies. "Small RNAs are probably deposited in oocytes of every animal," he hypothesizes. ...

October 2008 Biology of Reproduction highlights

... Perils of culture. There is growing interest in the developmental origins of adult disease, and effects of both nutrition and environment on oocytes and embryos on adult health of offspring have been demonstrated. However, mechanisms by which deleterious effects are established during these early ...

Cryopreservation techniques bring hopes for women cancer victims and endangered species

... involves slow freezing, which minimises the damage caused by forming ice crystals to the follicles, the reproductive units containing the individual oocytes (eggs). However a new approach based on vitrification may achieve even better results, with both methods discussed at the ESF conference. ...

Stem cell research puts interstate rivalry on hold

... the most robust cell lines," Dr Verma said. The NSW project team, led by Professor Bernie Tuch, will investigate another method of obtaining oocytes from consenting adult cancer patients who have had their ovaries removed. Professor Tuch's team will also use their proficiencies in characterising ...

IVF does not increase risk of developmental disorders in children

... after IVF/ICSI with controlled ovarian hyperstimulation (the conventional method, where the ovaries are stimulated with hormones to produce multiple oocytes (egg cells)) and 57 singletons born following IVF/ICSI in a modified natural cycle of oocyte production, where the one egg cell which develops ...

Biology of Reproduction highlights

... of Biology of Reproduction , find that the sex of bovine embryos positively correlates with pre-ovulatory follicular testosterone. How exposure of oocytes to follicular testosterone may influence the ability of a metaphase II egg to be preferentially inseminated by a Y-bearing sperm remains a mystery. ...

Biophysical Society announces 2008 International Travel Awards

... and Hydration of Curved and Ripples States of Lipid Interphases. Silvina B. Gayol, Centro de Neurociencia de Valparaiso, Chile, In Xenopus oocytes Glycosylation of Shaker K+ Channels Alters its Expression in the Plasma Membrane and Activation Kinetics. Iffath A. Ghouri, University of ...

New insight into the mechanisms of voltage sensing and transduction in biological processes

... and whether depolarisation or hyperpolarisation induced the phosphatase activity. By expressing phosphoinositide-specific sensors in Xenopus oocytes and applying both electrophysiology and imaging of phosphoinositides, it was shown that enzyme activity is activated upon depolarisation (not upon ...

Penn study on lung-infecting bacterial enzyme suggests new approach to cystic fibrosis treatment

... the disruptive action of SMase in frog oocytes (egg cells) engineered to place CFTR in their membrane. These oocytes are an experimental tool that allows the ... found that direct exposure of the CFTR-containing oocytes to SMase of Staphylococcus aureus and Bacillus ...

Fertility hope as study shows eggs survive in older ovaries

... female mammals are born with a finite number of oocytes (eggs). Two years ago, international ... In the mammalian ovary, reproductive cells called oocytes (eggs) develop within ovarian follicles. In ... said. "The mechanism behind renewable oocytes is still unknown," he said. "Although other ...

New egg freezing technique offers hope to hundreds of women

... more than 90% survival rate for the freeze-thawed oocytes and a high pregnancy rate of nearly 42% after the oocytes had been fertilised and implanted in the women. ... we can achieve post-thaw survival rates for oocytes of 90-95%, making oocyte cryopreservation a real ...

Israeli scientists successfully transplant frozen-thawed ovaries in sheep

... frozen and thawed ovaries in sheep, retrieved oocytes from these ovaries and triggered them in the ... that the ovaries in the two sheep from which oocytes were recovered were still functioning normally ... remove, freeze, thaw and replace ovaries, obtain oocytes and maintain normal ovarian long-term function. ...

Invitrogen Launches i-Path -- A Unique Systems Biology Platform at BIO 2005

... in humans. However, there are few human MII oocytes available for research because almost all that ... treatment are used to treat the patient. Immature oocytes are not used routinely for treatment at present, ... can be donated for research. These immature oocytes are arrested in the prophase I stage, before ...

Scientists succeed in cloning human embryos from eggs matured in the lab

... in humans. However, there are few human MII oocytes available for research because almost all that ... treatment are used to treat the patient. Immature oocytes are not used routinely for treatment at present, ... can be donated for research. These immature oocytes are arrested in the prophase I stage, before ...

Human Eggs Can Develop From Ovarian Surface Cells In Vitro

... (OSE) cells derived from adult human ovaries. oocytes derived from the culture of OSE cells developed ... research of adult human ovaries has shown that oocytes and granulosa cells (the layer of small cells ... mature eggs. However, definitive proof that new oocytes may develop in adult human females will be if ...

SuperLigands - a database of ligand structures derived from the Protein Data Bank

... "somatic cell nuclear transfer" or SCNT. Next, oocytes with the patient's genetic material were allowed ... and colleagues replaced the nuclei from donated oocytes with nuclei from skin cells from male and female ... transfer with skin cells of males or females and oocytes from biologically-unrelated females. Other ...

Scientists generate patient-specific stem cells, Science study says

... "somatic cell nuclear transfer" or SCNT. Next, oocytes with the patient's genetic material were allowed ... and colleagues replaced the nuclei from donated oocytes with nuclei from skin cells from male and female ... transfer with skin cells of males or females and oocytes from biologically-unrelated females. Other ...

Heavy smoking cuts women's chance of pregnancy -- even with donated oocytes

... first to examine the impact of smoking in women who have received donated oocytes ?the situation that allows the most objective assessment of the role of ... pregnancy. The fact that we see this result in a situation in which the oocytes were donated by other women demonstrates that cigarette smoking negatively ...

FSU biologists uncover mechanisms that shape cells for better or worse

... communication that triggers the development of cell polarity in Drosophila oocytes (unfertilized fruit fly eggs) also are known players in the pathogenesis ... "Such a discovery in the biological model provided by Drosophila oocytes has broad implications in humans, where, for example, neurons in the brain ...

Component in soy products causes reproductive problems in laboratory mice

... separate and therefore develop abnormally. The researchers explain that oocytes that remain in clusters are less likely to become fertilized based on ... the genistein treated group were single We think genistein inhibits the oocytes or egg cells from separating apart," said Wendy Jefferson, Ph.D. of NIEHS ...

Scientists clone mice from adult skin stem cells

... Biology and Neurogenetics, headed by senior co-author Peter Mombaerts. To execute the nuclear transfer procedure, Li took unfertilized mouse oocytes and replaced the nucleus of each oocyte with a nucleus from these adult skin stem cells. A main hurdle in nuclear transfer with adult cells has ...

With few factors, adult cells take on character of embryonic stem cells

... embryo. Cells from other parts of the body can also be "reprogrammed" by transferring their nuclear contents into egg cell precursors called oocytes or by fusion with embryonic stem cells, earlier studies showed. Those findings provided evidence that unfertilized eggs and embryonic stem cells ...

With few factors, adult cells take on character of embryonic stem cells

... embryo. Cells from other parts of the body can also be "reprogrammed" by transferring their nuclear contents into egg cell precursors called oocytes or by fusion with embryonic stem cells, earlier studies showed. Those findings provided evidence that unfertilized eggs and embryonic stem cells ...

Researchers devise new technique for creating human stem cells

... (SCNT), a method that is currently used to produce human stem cells. SCNT involves transferring the nuclei of adult cells, called somatic cells, into oocytes in which scientists have removed the nuclei. The researchers said that -- while the technique might one day be used along with SCNT, which ...

Technique may allow cancer patients to freeze eggs, preserving fertility before starting treatment

... from liquid to solid is instantaneous. No ice crystals form and the consistency resembles a viscous glassy state. Research so far has used mouse oocytes but U-M expects to make the technology available in the clinic soon. "With traditional slow-freeze techniques, just over half the eggs survive the ...