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Query: UMLS:C0016382 (flushing)
 6,387 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A service programme of in-vitro fertilization ( IVF ) and embryo transfer (ET) has been established in a small unit in Western Australia after a successful pilot study which was undertaken in 1981. The key features of the programme include simplified monitoring of the follicular phase of stimulated cycles; oocyte retrieval and ET are both undertaken during routine daytime work schedules. The results of the first eight months of the programme are presented, during which 13 further pregnancies were generated and 10 healthy infants were delivered (seven boys and three girls). In the last session in which 49 patients took part a mean of 2.3 mature preovulatory oocytes were collected by means of a double-lumen aspiration/flushing needle from 98% of 48 patients who reached the laparoscopy stage. Ninety-four per cent of 48 patients proceeded to embryo transfer by means of a double-catheter technique; the pregnancy rate was 20.8% per laparoscopy or 22.7% per embryo transfer.
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PMID:In-vitro fertilization in Western Australia. A viable service programme. 623 44

The aim of our study was to define the conditions for IVM and IVF of oocytes in 2 common deer species as models for endangered related subspecies. Immature oocytes were recovered during the breeding season from postmortem ovaries (red deer) or by repeated laparoscopic follicular aspiration (sika deer). Oocytes were cultured for 24 h in IVM medium supplemented with EGF or FSH and follicular fluid. Stag semen was collected by electroejaculation (both species) or by epididymal flushing (red deer) and cryopreserved. For IVF, oocytes were exposed to different concentrations of thawed spermatozoa in a modified Tyrode albumin lactate pyruvate medium supplemented with 20% (v/v) estrus sheep serum for 18 h. After IVF, presumptive zygotes were allowed to develop in vitro for 7 days in synthetic oviduct fluid (SOF) supplemented with fetal calf serum (10%, v/v). In both species, the presence of ovine FSH and follicular fluid improved the in vitro maturation rate. In the sika deer, the optimal sperm concentration for IVF was 10(6)/mL and some fertilized oocytes reached the early morula stage (20 to 25 cells). In the red deer, after IVF with ejaculated or epididymal spermatozoa (2.0 x 10(6)/mL), 20% of zygotes developed to the blastocyst stage (50 to 80 cells).
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PMID:Successful in vitro production of embryos in the red deer (Cervus elaphus) and the sika deer (Cervus nippon). 1123 90

We examined transgenic-cattle production by DNA microinjection into 1-, 2-, and 4-cell embryos, analyzing the impact on calf size and subsequent viability. Embryos were either collected at an abattoir by flushing oviducts from superovulated and artificially inseminated cows (in vivo-derived) or obtained by in vitro maturation and in vitro fertilization of oocytes aspirated from excised ovaries (in vitro-derived). A human serum albumin (hSA) milk-expression DNA construct was microinjected, either in one of the visible pronuclei of in vitro- and in vivo-derived 1-cell embryos or in the nuclei of two blastomeres of 2- and 4-cell in vivo-derived embryos. Microinjection-induced mortality (lysis and developmental block) was equivalent ( approximately 40%) for all microinjected embryos. Embryos were co-cultured with BRL cells in B-2 medium containing 10% fetal calf serum (FSC). Overall, embryo development to morulae/blastocysts was significantly greater for in vivo-derived ova (15.5%) than for in vitro-derived oocytes (9.3%). All morulae and blastocysts were transferred to synchronized recipient females on Days 6-8 post-fertilization. A total of 189 calves were delivered. Birth weights were significantly greater for calves generated from in vitro-derived oocytes compared with those generated from in vivo-derived oocytes. One transgenic bull calf was obtained from the microinjection of a 2-cell embryo. Fluorescence in situ hybridization (FISH) analysis of lymphocytes detected one transgenic integration site in all cells. Transmission frequency of the hSA transgene in embryos obtained through IVM/IVF/IVC utilizing the semen of the transgenic calf confirmed that it was not mosaic.
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PMID:Transgenic production from in vivo-derived embryos: effect on calf birth weight and sex ratio. 1155 Feb 65

Laparoscopic ovum pick-up (LOPU) is a convenient methodology by which oocytes can be recovered and used either for in vitro production of zygotes or as a source of cytoplasts in nuclear transfer (NT) procedures. The pregnancy and transgenesis rates achieved with IVM/IVF of LOPU-sourced oocytes followed by subsequent DNA microinjection of zygotes are similar to the rates obtained when using in vivo-produced oocytes or zygotes. Similarly, pregnancy rates and kids born by using LOPU-sourced and in vitro matured oocytes as recipient cytoplasts in NT programs are comparable with those reported by others using in vivo matured oocytes collected by oviduct flushing. The use of LOPU allows for improved control over the stage of maturation/development of the oocytes and produced zygotes, a less invasive means of recovery, thereby allowing for repeated usage of the oocyte donor animals and the ability to source the oocytes from live animals of known health status. In addition, because of large follicular responses that can be obtained from prepubertal animals, LOPU followed by IVM/IVF has demonstrated great potential for the early propagation of valuable animals, in particular, transgenic animals.
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PMID:Advances in the production and propagation of transgenic goats using laparoscopic ovum pick-up and in vitro embryo production technologies. 1177 75

The empty follicle syndrome (EFS) is defined as a lack of retrieved oocytes from follicles, at the time of repeated aspiration and flushing, following ovulation induction. The actual mechanism responsible for the EFS is still unknown. The aim of this study was to offer more information regarding the possible connection of this syndrome with pericentric inversion of chromosome 2. We give a case report of a patient who had multiple failed IVF attempts, due to the absence of oocyte and granulosa cells in the follicular fluid, following oocyte retrieval in both stimulated and natural cycles. Chromosomal analysis showed the presence of a pericentric inversion of chromosome 2: 46,XX,inv(2)(p11q21) in the female partner karyotype, while the male partner had a normal karyotype. Our case showed possible genetic factor influence in the aetiology of EFS.
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PMID:Pericentric inversion of chromosome 2 in a patient with the empty follicle syndrome: case report. 1590 90

It may be possible to avoid inadequate in vitro culture conditions by incubating gametes or embryos in the oviducts for a short time. Ideally, an optimized procedure should be devised, combining in vitro and in vivo systems, in order to achieve synchronization in cattle. We transferred gametes as well as embryos in various stages of development and placed them into the oviducts. Embryos were recovered on Day 7 by flushing of oviducts and uterine horns. Blastocyst rates were determined on Day 7 and on Day 8. Experimental designs included transfer of in vitro matured cumulus oocyte complexes into previously inseminated heifers (COCs group), transfer of in vitro matured COCs simultaneously with capacitated spermatozoa (GIFTs group), transfer of four to eight cell stage embryos developed in vitro after IVM/IVF (Cleaved Stages group) and a group of solely in vitro produced embryos (IVP control group). Our results indicate that in vivo culture of IVM/IVF embryos in the homologous bovine oviduct has a positive influence on subsequent pre-implantation development. In addition, we have evidence that in vitro maturation and in vivo fertilization cannot be synchronized.
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PMID:Intrafallopian transfer of gametes and early stage embryos for in vivo culture in cattle. 1593 40

The object of this study was to determine the optimum number of follicular flushing for a maximum number of oocytes to be retrieved. This was a prospective study, based at a private in vitro fertilization centre (Brentwood Fertility Centre, The Essex Nuffield Hospital, Brentwood, Essex UK). Patients attending the IVF centre for assisted reproductive technology were studied. We counted the number of oocytes obtained with each flushing after primary aspiration of the follicle. Some 40% of the oocytes were retrieved with primary aspiration without follicular flushing, while up to 82% of oocytes were retrieved with two flushes and 97% of oocytes were retrieved in up to four flushes. Only 3% of the remaining oocytes were retrieved with 5th and 6th flush. The optimum number of follicular flushing was four times, in order to achieve maximum number of oocytes without compromising the duration of retrieval and number of oocytes retrieved.
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PMID:Is there a benefit from routine follicular flushing for oocyte retrieval? 1609 24

A transvaginal ultrasound guided follicular aspiration technique was developed for the repeated collection of bovine oocytes from natural cycling cows. In addition, the feasibility of using this method for collecting immature oocytes for in vitro embryo production was also evaluated. Puncturing of visible follicles for ovum pick-up was performed in 21 cows over a three month period. All visible follicles larger than 3 mm were punctured and aspirated three times during the estrous cycle on Day 3 or 4, Day 9 or 10 and Day 15 or 16. The mean (+/- SEM) estrous cycle length after repeated follicle puncture was 22.2 +/- 0.3 days. The mean total number of punctured follicles per estrous cycle was 12.6 +/- 0.3. The largest (P<0.05) number of follicles punctured (5.1 +/- 0.3) for ovum pick-up was on Day 3 or 4 of the estrous cycle. The overall recovery rate of 541 punctured follicles was 55%. Most oocytes (P<0.05) were aspirated from follicles smaller than 10 mm. Following in vitro maturation and fertilization (IVM/IVF), 104 oocytes were transferred to sheep oviducts. Six days later, 75 ova/embryos were recovered, after flushing the oviduct of the sheep, of which 24% developed into transferable morulae and blastocysts. In this study, a reliable nonsurgical, follicular aspiration procedure was used for the repeated collection of immature oocytes which could be used successfully for in vitro production of embryos. This procedure offers a competitive alternative to conventional superovulation/embryo collection procedures.
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PMID:Transvaginal ultrasound guided follicular aspiration of bovine oocytes. 1672 54

Various needle sizes (17- and 20-g) and aspiration pressures (25, 50, 75 and 100 mmHg) were used to aspirate a total of 5,827 ovarian follicles from bovine ovaries from a slaughterhouse source to assess the impact on the quantity and quality of recovered immature oocytes. The cumulus oocyte complexes (COC's) were graded according to the presence and consistency of cumulus cells surrounding the oocyte and the data analyzed using general linear models. Overall recovery rates and the recovery of oocytes considered viable for IVM/IVF procedures (Classes A, B and C) were both significantly higher using a 17-g needle than a 20-g needle (P < 0.01). As the vacuum pressure increased so did the recovery rate of the total number of oocytes, although the number of viable oocytes reached a maximum at a calculated vacuum pressure of 55 mmHg for the 17-g needle and 77 mmHg for the 20-g needle, with an increased incidence of denuded oocytes at higher vacuum pressures. In a second experiment conducted on 1, 473 follicles, no significant difference was found between 17-g double (flushing) and 17-g single lumen needles in the recovery rate of either the total number or number of viable oocytes when using a vacuum pressure of 50 mmHg.
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PMID:The collection of oocytes from bovine ovaries. 1672 47

To evaluate the importance of follicular flushing on semi natural cycles IVF, we have compared prospectively the reproductive potential of oocytes obtained from follicular fluid (group A, n = 79) to those obtained from follicular flushing (group B, n = 47) in 146 oocyte pick-ups. The groups A and B were similar on the fertilisation rate (79.7% versus 88.1%, respectively), percentage of superior grade embryos (28.8% versus 37.8%) and the implantation rate (24.1% versus 44.1%) and 53.6% of total clinical pregnancies were obtained from group B. The practice of follicular flushing on IVF semi natural cycle improves the pregnancy rate. The oocytes obtained by follicular flushing had the same reproductive potential than those obtained on follicular fluid.
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PMID:Optimising the semi natural cycle IVF: the importance of follicular flushing. 1724 Jul 97


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