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Kobayashi Yukimasa - - 2002
The early embryonic development and features of the developing embryo of the glowworm Rhagophthalmus ohbai are described chiefly by light microscopy, with emphasis on the germ rudiment formation and its phylogenetic implication. The egg period is 30-34 days at about 23 degrees C. The newly laid egg is a short ...
Phillips Todd A - - 2002
Application of organophosphorus (OP) insecticides to agricultural fields during the spring often overlaps the period of spawning, egg incubation, and larval stages of fish species such as walleye (Stizostedion vitreum). Because life stage can affect uptake, distribution, and effects of contaminants, our objective was to identify the most sensitive life ...
Heulin Benoit - - 2002
The concept of the oviparity-viviparity continuum refers to the wide range in the length of intrauterine egg retention and, hence, in the stage of embryonic development at oviposition existing in squamates. The evolutionary process underlying this continuum may involve not only a lengthening of egg retention in utero, but also ...
Spandorfer Steven D - - 2002
OBJECTIVE: To analyze the effectiveness of autologous endometrial coculture by the cycle day of the endometrial biopsy. DESIGN: Retrospective study. SETTING: University-based IVF center. PATIENT(S): Two hundred eight patients with multiple IVF failures. INTERVENTION(S): Embryos were split and randomly allocated to growth on autologous endometrial coculture or conventional media. MAIN ...
Rienzi Laura - - 2002
OBJECTIVE: To examine whether the developmental potential of embryos that were partially damaged after freezing and thawing can be improved by removal of necrotic blastomeres before embryo transfer. DESIGN: Prospective pilot study and observational clinical series. SETTING: Private hospital. PATIENT(S): Two hundred thirty-five infertile couples undergoing frozen embryo transfer. INTERVENTION(S): ...
Reed Michael L - - 2002
The purpose was to investigate vitrification of human blastocysts using the cryoloop. Thirteen couples elected to have blastocysts cryopreserved via vitrification (N = 54 blastocysts). Embryos were exposed to two vitrification solutions, pipetted onto the cryoloop then plunged into liquid nitrogen. On the day of embryo replacement, blastocysts were warmed ...
Hannak Eva - - 2002
gamma-Tubulin-containing complexes are thought to nucleate and anchor centrosomal microtubules (MTs). Surprisingly, a recent study (Strome, S., J. Powers, M. Dunn, K. Reese, C.J. Malone, J. White, G. Seydoux, and W. Saxton. Mol. Biol. Cell. 12:1751-1764) showed that centrosomal asters form in Caenorhabditis elegans embryos depleted of gamma-tubulin by RNA-mediated ...
Costa F E S - - 2002
Uteri from four pregnant females and two newborn of shortfin mako, Isurus oxyrinchus, were collected in the southeastern region of Brazil, during September, October, and November of 1993 and 1994. All embryos were near-term with developing dentition and inner organs. Total length ranged from 64.5 to 72.0 cm, and the ...
Cocero M J - - 2002
Cryopreservation of sheep embryos with ethylene glycol as a protectant appears to be more effective than glycerol, particularly at the morula stage, as has been demonstrated on the basis of in vitro and in vivo development rates after thawing. In this study we compare the ultrastructure of fresh morulae, thawed ...
Roudebush W E - - 2002
BACKGROUND: A definitive need exists to identify a biomarker of embryonic viability. Platelet-activating factor (PAF) production by human embryos is related to pregnancy potential. METHODS: Conditioned embryo culture media were obtained following conventional IVF on day 3, with PAF levels and pregnancy outcomes correlated. RESULTS: Overall pregnancy rate was 68% ...
Takada Norio - - 2002
The T-box transcription factor gene Brachyury is important for the differentiation of notochord in all chordates, including the ascidians Halocynthia roretzi and Ciona intestinalis. We isolated Brachyury from molgulid ascidians, which have evolved tailless larvae multiple times independently, and found the genes appear functional by cDNA sequence analyses. We then ...
Quintans Carlos J - - 2002
OBJECTIVE: To report successful pregnancy from embryos that had been cryopreserved for 8.9 years. DESIGN: Case report. SETTING: Fertility clinic of the University of Buenos Aires School of Medicine. PATIENT(S): A 43-year-old woman with ovarian failure and a 45-year-old man with nonobstructive azoospermia underwent embryo donation.I NTERVENTION(S): Five embryos that ...
Höchel Joachim - - 2002
Heart rate (HR) of Muscovy duck embryos (Cairina moschata f. domestica) was continuously recorded from the 21st day of incubation (E21) until hatching (E35). During that period, embryos were exposed to different acoustic stimuli (species-specific maternal and duckling calls, music, rectangular and sine waves, white noise). Sudden HR changes occurred ...
King T J - - 2002
Embryo transfer and pregnancy maintenance strategies in pigs were evaluated with reference to situations in which limited numbers of viable embryos or micromanipulated embryos are available, such as pig cloning. Development of embryos with compromised zona pellucida was compared with development of embryos with intact zona pellucida. Micromanipulation had no ...
Miller D L - - 2002
Bobcats (Lynx rufus) (n=22) were used to test a surgical embryo transfer protocol for wild felines. Five blastocysts were collected 8-14 days post-initial copulation (PIC). Translucent capsule-like structures were recovered at 12 days PIC and are the first report of such a structure in a felid. Endometrial fibrosis was observed ...
Wrathall A E - - 2002
Semen from 13 bulls, eight with clinical bovine spongiform encephalopathy (BSE), was used to artificially inseminate (AI) 167 cows with clinical BSE, and their resultant embryos were collected non-surgically seven days after AI. The viable and non-viable embryos with intact zonae pellucidae were washed 10 times (as recommended by the ...
Miyata Masaaki - - 2002
Microsomal epoxide hydrolase (mEH) catalyzes the hydrolysis of epoxide intermediates derived from drugs and environmental chemicals. The response of in vivo (embryo) and in vitro (embryo fibroblast) tests were analyzed using mEH-null and wild-type mice to determine the relative role of maternal and embryonic mEH in the developmental toxicity induced ...
Kusama Tomoko - - 2002
Application of diagnostic X-ray examination to pregnant women is complicated since risks to both mother and embryo/fetus must be considered. Embryos and fetuses are more sensitive to radiation than adults or children. The threshold doses for fetal death, malformations and mental retardation which are deterministic effects, are reported to be ...
Moreira F - - 2002
Previous studies indicated that the use of bovine somatotropin (bST) in concurrence with a timed artificial insemination (TAI) protocol increased pregnancy rates. However, the mechanisms for such a bST effect on fertility were not clear. Objectives of this study were to determine the effects of bST on fertilization and early ...
García-Ximéne Fernando - - 2002
The female parthenogenetic haploid embryos can be stored long-term by cryopreservation. Briefly, rabbit haploid parthenotes at the 32-cell stage were produced by electroactivation and in vitro culture. At this embryonic stage, parthenotes were individually cryopreserved by a slow-freezing procedure. After thawing, every embryo was disaggregated and blastomeres used as haploid ...
Iwaki Takayuki - - 2002
In humans, maternal fibrinogen (Fg) is required to support pregnancies by maintaining hemostatic balance and stabilizing uteroplacental attachment at the fibrinoid layer found at the fetal-maternal junction. To examine relationships between low Fg levels and early fetal loss, a genetic model of afibrinogenemia was developed. Pregnant mice homozygous for a ...
Byrd William - - 2002
Cryopreservation of human embryos is a routine procedure in most assisted reproductive technology laboratories. Embryos can be successfully frozen at the pronuclear, multicellular (four to eight blastomeres), and blastocyst stages. Each laboratory has to determine which freezing protocol is best suited for its patients. Freezing protocols have been developed that ...
Libik M - - 2002
The severe loss of developmental competence affecting fertilized ova when removed from the oviductal environment suggests that this organ plays a functional role in early embryonic development. The purpose of this study was to determine the effect of sheep heat-inactivated OF on the mortality rate of ovine embryos produced in ...
Bodó S - - 2002
This article presents a new, simple and rapid embryo biopsy method. The blastomere for genetic analysis can be separated from a precompacted mouse embryo after a partial zona digestion with the use of a holding pipette. For the micromanipulation only two microcapillaries and micromanipulators are needed. The development of the ...
Malpani A - - 2002
We describe our experience with the use of embryo biopsy and fluorescent in-situ hybridization (FISH) in order to sex embryos for the purpose of family balancing in a private IVF clinic in India from April 1999-April 2001. Embryos were biopsied and analysed on day 3, cultured in sequential media, and ...
Nakayama Takahiro - - 2002
BACKGROUND: The aim of this study was to investigate the role of peripheral blood mononuclear cells (PBMC) in embryo invasion at the implantation site and to estimate the effect on PBMC function of human chorionic gonadotrophin (HCG) that is secreted from the human embryo. METHODS AND RESULTS: The effect of ...
Barton S C - - 2001
In the normal diploid mouse embryo, active demethylation of the paternal genome but not of the maternal genome occurs within only a few hours and in a highly coordinated fashion as the zygote proceeds through the first G1 phase. This zygotic demethylation may be necessary to reprogram the sperm genome ...
Wlodarczyk B - - 2001
Arsenic is a well-known carcinogen, which has been suspected of being a human teratogen, although there is currently insufficient and inadequate supportive data to make any definitive judgments. In addition, the significance of individual genetic differences on pregnancy outcomes following in utero exposure to arsenic is currently unknown. In order ...
Hasler J F - - 2001
The effects of a large number of factors on the pregnancy rates of fresh and frozen cattle embryos were examined over a period of years at several different locations. For fresh embryos, overall pregnancy rates were 68.3% (n=9023) and 77.1% (n=2650) at different locations and time periods. Frozen-thawed embryo pregnancy ...
Spandorfer S D - - 2001
PROBLEM: To determine if LIF produced by autologous endometrial co-culture (ECC) was associated with outcome in 46 patients with a history of multiple IVF failures. METHOD OF STUDY: The conditioned media (CM) from ECC cells exposed or non-exposed to human embryos was analyzed for LIF. RESULTS: Exposure or non-exposure to ...
Carp H - - 2001
Recurrent miscarriage may be due to an inherently abnormal embryo (e.g. chromosomal aberrations), or maternal factors (e.g. uterine anomalies or antiphospholipid antibodies). However, there may be another mechanism; fetuses may have anomalies induced by toxic maternal factors. Early ultrasound scanning has revealed structural anomalies in karyotypically normal embryos in pregnancies ...
Lundin K - - 2001
BACKGROUND: In order to decrease multiple birth rates without decreasing birth rates overall, it is important to increase the capability of selecting the most optimal embryos for transfer. It has been shown that human embryos which cleave early, i.e. complete the first mitotic division within 25-27 h post insemination, provide ...
Barros C M - - 2001
In the present short review superovulation treatments commonly used for Bos taurus and/or Bos indicus will be addressed with emphasis in recent superstimulation protocols associated with pharmacological manipulation of the follicular dynamics to improve donor management and potentially embryo yield. Results obtained after superovulation treatments in which the time of ...
Henry J Q - - 2001
Molecular and morphological comparisons indicate that the Echinodermata and Hemichordata represent closely related sister-phyla within the Deuterostomia. Much less is known about the development of the hemichordates compared to other deuterostomes. For the first time, cell lineage analyses have been carried out for an indirect-developing representative of the enteropneust hemichordates, ...
Nowshari M A - - 2001
BACKGROUND: The effects of exposure time (20 versus 45 s) to a high concentration of cryoprotectant (7.0 mol/l ethylene glycol with 0.5 mol/l sucrose) and freezing rates (1200-10 300 degrees C/min) during rapid freezing of mouse pronuclear stage embryos on survival and development to blastocysts were investigated. Different freezing rates ...
Yokota Y - - 2001
OBJECTIVE: To avoid the risk of ovarian hyperstimulation syndrome and promote pregnancy rate by freezing pronuclear embryos at the oocyte retrieval and using developed refrozen supernumerary embryos in the event of failed pregnancies. DESIGN: A case study. SETTING: Private IVF center. PATIENT(S): Healthy infertile woman undergoing IVF treatment. INTERVENTION(S): Slowly ...
Domingo J L - - 2001
Although the biokinetics, metabolism, and chemical toxicity of uranium are well known, until recently little attention was paid to the potential toxic effects of uranium on reproduction and development in mammals. In recent years, it has been shown that uranium is a developmental toxicant when given orally or subcutaneously (SC) ...
Balaban B - - 2001
BACKGROUND: Embryo quality may be accurately assessed as early as the pronuclear zygote phase, as shown in recent studies. However, it is not known whether good quality zygotes are destined to become good quality cleavage stage embryos and blastocysts. METHODS: In this retrospective study, 86 intracytoplasmic sperm injection-embryo transfer cycles ...
Haque M - - 2001
There is still some controversy as to whether sacral spina bifida in humans is the result of a defect of the primary or secondary neural tube. As somites are related to the development of vertebrae and the primary neural tube is related to the development of the spinal cord in ...
Stepan H - - 2001
C-Type natriuretic peptide (CNP) is a vasoactive hormone and the endothelial component of the natriuretic peptide system. We examined the expression of CNP in mouse reproductive organs and embryos at different stages of gestation. Pregnant mice were killed and embryos were dissected on gestational days 9.5, 12.5, 15.5, 18.5 postconceptionem ...
Munthe C - - 2001
The phenomenon of twinning in early fetal development has become a popular source for doubt regarding the ascription of moral status to early embryos. In this paper, the possible moral basis for such a line of reasoning is critically analysed with sceptical results. Three different versions of the argument from ...
Gabrielsen A - - 2001
BACKGROUND: The study represents a prospective randomized controlled study evaluating zona pellucida thickness variation (ZPTV) measurements versus conventional selection of embryos using classic embryo score criteria, prior to embryo transfer in human IVF/intracytoplasmatic sperm injection (ICSI). METHODS: Eighty-six patients having > or =3 embryos, with a classic embryo score of ...
Salumets A - - 2001
BACKGROUND: Recent studies have shown that zygote morphology could be used for the assessment of human embryo quality. Pronuclear (PN) morphology is based on certain distinct features seen in zygotes 16-18 h after fertilization. In the present study PN stage morphology was assessed and combined with a single embryo transfer ...
Rátky J - - 2001
The objective of the study was to use embryo transfer (ET) for propagation of the Swallow Belly Mangalica population. Mangalica is a native Hungarian pig breed adapted to extreme climate and housing conditions and distinguished for excellent meat and fat quality. However, due to their weak reproductive characteristics and relatively ...
Fausto A M - - 2001
Newly laid eggs of stick insects comprise a unique fluid ooplasm that is gradually partitioned into a number of yolk granules by invasion of secondary vitellophages. This study aimed at establishing how yolk granules become acidified in the course of embryonic development. Data show that acidified yolk granules are rather ...
Rhodes R R Mount Sinai School of Medicine, New York, New York 10029, USA. - - 2001
People involved in assisted reproduction frequently make decisions about which of several embryos to implant or which of several embryos to reduce from a multiple pregnancy. Yet, others have raised questions about the ethical acceptability of using sex or genetic characteristics as selection criteria. This paper reviews arguments for rejecting ...
Techakumph M - - 2001
To investigate the development of fresh and frozen swamp buffalo embryos after transfer to synchronized recipients, 14 fresh embryos and 28 frozen embryos, collected from Thai swamp buffalo cows of an elite herd at the Surin Breeding Center, were transferred nonsurgically to 31 synchronized recipients buffalo cows. One fresh embryo ...
El-Danasouri I - - 2001
OBJECTIVE: To evaluate the efficacy and efficiency of freezing cleaved human embryos through vitrification. DESIGN: Clinical study of vitrification of human embryos. SETTING: Assisted reproductive technology centers. PATIENT(S): Thirty-six patients undergoing IVF-ICSI treatment whose surplus embryos were frozen. INTERVENTION(S): Two hundred fifteen surplus embryos vitrified, subsequently thawed, and transferred in ...
Böttger S A - - 2001
The embryos of the sea urchin Lytechinus variegatus are capable of surviving chronic exposure to inorganic sodium phosphate and organic triethyl phosphate concentrations as high as 6 and 1000 mg l(-1) seawater, respectively. However, chronic exposure to sub-lethal concentrations of these phosphates may cause arrested or abnormal embryonic development. We ...
Spell A R - - 2001
The objectives of this experiment were to determine the effects of corpus luteum characteristics, progesterone concentration, donor-recipient synchrony, embryo quality, type, and developmental stage on pregnancy rates after embryo transfer. We synchronized 763 potential recipients for estrus using one of two synchronization protocols: two doses of PGF2alpha (25 mg i.m.) ...
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