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1.
J Phys Condens Matter ; 31(14): 144001, 2019 Apr 10.
Article in English | MEDLINE | ID: mdl-30625435

ABSTRACT

Antiphase domains are three-dimensional crystal defects commonly arising at the interface of III-V semiconductors and Si. While control over their formation has been achieved, the geometry of the antiphase domain itself that is separated from the mainphase of the crystal by the so-called antiphase boundary, has not yet been fully understood. In this work, we first investigate the interface between GaP and Si itself by cross-sectional scanning tunneling microscopy (XSTM) to reveal possible intermixing within an 8 monolayers wide region. Furthermore, we present an extensive analysis combining transmission electron microscopy and XSTM to elucidate the shape of antiphase domains in GaP. To create a true-to-scale, three-dimensional model of an antiphase domain, firstly, plan-view transmission electron microscopy images are drawn on. Subsequently, the progression of many antiphase boundaries through the GaP crystal as viewed from the (1 1 0) and (1 [Formula: see text] 0) cleavage planes is analyzed all the way down to the atomic level by means of XSTM. This enables a detailed analysis of the shape and physical dimensions of the antiphase domains. A typical measured extension in growth directions is found to be a maximum of 60 nm and the maximum measured extension of the base plane in [[Formula: see text] 1 0] and [1 1 0] directions is about 160 nm and 50 nm, respectively. They appear as pyramids with anisotropic base planes whose side facets kink many times.

2.
Reprod Domest Anim ; 52(3): 495-504, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28332235

ABSTRACT

Improving our understanding of the mechanisms controlling the corpus luteum (CL) and its role in regulating the reproductive cycle should lead to improvements in the sustainability of today's global animal industry. The corpus luteum (CL) is a transient endocrine organ composed of a heterogeneous mixture steroidogenic, endothelial and immune cells, and it is becoming clear that immune mechanisms play a key role in CL regulation especially in luteolysis. Toll-like receptors (TLR) mediate innate immune mechanisms via the production of pro-inflammatory cytokines, especially within various tissues, although the role of TLR within CL remains unknown. Thus, the objectives of this study were to characterize TLR mRNA expression in the CL during the oestrous cycle and in pregnancy (day 30-50), and to examine the role of TLR signalling in luteal cells. Corpora lutea were collected at various stages of the cycle and pregnancy and analysed for TLR and cytokine mRNA expression. In addition, luteal cells were cultured with the TLR4 ligand (lipopolysaccharide, LPS) for 24 h to evaluate the role of TLR4 in regulating luteal function. Toll-like receptors 1, 2, 4, 6, tumour necrosis factor alpha (TNF), interferon gamma (IFN-G), and interleukin (IL)-12, mRNA expressions were greatest in regressing CL compared with earlier stages (p < .05), whereas no change was observed for IL-6 mRNA expression. Cytokine mRNA expression in cultured luteal cells was not altered by LPS. Based on these data, one or more of the TLRs found within the CL may play a role in luteolysis, perhaps via pro-inflammatory cytokine mRNA expression.


Subject(s)
Corpus Luteum/metabolism , Cytokines/genetics , Estrous Cycle/genetics , Pregnancy, Animal/genetics , RNA, Messenger/genetics , Toll-Like Receptors/genetics , Animals , Cattle , Corpus Luteum/drug effects , Estrous Cycle/metabolism , Female , Gene Expression Regulation , Lipopolysaccharides/pharmacology , Luteolysis/genetics , Pregnancy , Pregnancy, Animal/metabolism , RNA, Messenger/metabolism , Toll-Like Receptors/metabolism
3.
Domest Anim Endocrinol ; 52: 75-81, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25917140

ABSTRACT

The hormone progesterone is essential for proper embryonic development. The objective of this study was to examine the relationship between recipient serum concentrations of progesterone, at the time of embryo transfer and at conceptus recovery, on conceptus development from in vivo- or in vitro-produced embryos. Embryos were produced in vivo by superovulation of Holstein cows (IVO; n = 17) or in vitro with either serum-containing (IVPS; n = 27) or serum-restricted medium (IVPSR; n = 34). Single grade I blastocysts from each embryo production system were transferred into heifers on day 7 of development. Conceptuses were recovered on day 17 of gestation and classified as complete, degenerated, or no conceptus. Compared with the IVO group, in vitro-produced embryos had more (P = 0.055) degenerated conceptuses (IVO, 0%; IVPS, 18.5%; and IVPSR, 20.6%). There were no differences in progesterone concentrations at the time of transfer when recipients received either male or female embryos (P > 0.05). Progesterone concentrations in recipients receiving in vivo-produced embryos were higher (P < 0.05; 3.74 ± 0.4 ng/mL; least-squares mean ± standard error of the mean) on day 7 compared with those receiving in vitro-produced embryos (IVPS, 2.4 ± 0.2; IVPSR, 2.58 ± 0.3 ng/mL). However, there was no difference in progesterone concentration on day 7 between treatment groups for heifers from which short conceptuses (≤194 mm) were recovered on day 17. In contrast, when longer (>194 mm) conceptuses were recovered on day 17, heifers receiving in vitro-produced embryos had lower (P = 0.05) serum concentrations of progesterone on day 7 compared with those receiving in vivo-produced embryos (IVPS, 2.2 ± 0.5; IVPSR, 2.3 ± 0.5; IVO, 3.9 ± 0.5 ng/mL). In conclusion, differences in autonomy may exist between in vitro- and in vivo-produced embryos during the period of conceptus elongation with in vitro-produced embryos relying more on intrinsic factors to influence elongation.


Subject(s)
Cattle/embryology , Embryonic Development/physiology , Fertilization in Vitro/veterinary , Progesterone/blood , Animals , Blastocyst/physiology , Embryo Transfer/veterinary , Female , Gestational Age , Male , Pregnancy , Superovulation
4.
Anim Reprod Sci ; 138(1-2): 64-73, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23473694

ABSTRACT

The insulin-like growth factor type 2 receptor (IGF2R) regulates fetal growth by removing IGF2 from circulation. In mice, expression of the Igf2r gene is only imprinted after implantation and is associated with expression of the antisense non-coding (nc)RNA, Airn. The objectives of this study were, first, to determine if bovine AIRN was expressed during developmentally important stages of gestation, and second, to determine if expression of bAIRN was affected by method of embryo production. Control reactions confirmed that sequence verified bAIRN PCR amplicons resulted from RNA within the sample and not from genomic DNA contamination. IGF2R mRNA was expressed in all fetal liver samples at Days 35-55 and 70 of gestation as well as in 8 of 9 Day 15 conceptuses, 10 of 10 Day 18 conceptuses, and in all day 7 blastocyst pools. bAIRN was expressed in all samples of fetal liver at Days 35-55 and 70 of gestation. The proportion of conceptuses that expressed bAIRN increased from 1 of 9 at Day 15 of gestation to 8 of 10 at Day 18 of gestation. No bAIRN was expressed in any blastocyst pools. The relative level of bAIRN was greater (P<0.05) in fetal liver from embryos produced in vivo compared to that from embryos produced in vitro. In summary bAIRN was not expressed in blastocyst-stage embryos, was expressed in an increasing proportion of embryos around the time of maternal recognition of pregnancy and was expressed following implantation. Furthermore, relative levels of bAIRN in bovine fetal liver can be altered by method of embryo production.


Subject(s)
Cattle/embryology , Embryo, Mammalian/metabolism , Fertilization in Vitro/veterinary , Gene Expression Regulation, Developmental/physiology , RNA, Untranslated/genetics , Receptor, IGF Type 2/metabolism , Animals , Female , Gene Expression Regulation, Developmental/genetics , Liver/metabolism , Male , Pregnancy , RNA, Messenger/chemistry , RNA, Messenger/genetics , Receptor, IGF Type 2/genetics , Reverse Transcriptase Polymerase Chain Reaction/veterinary
5.
Theriogenology ; 79(3): 453-61, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23182749

ABSTRACT

The main objective was to determine the efficacy of using X-sorted sperm to produce embryos in vitro for transfer into lactating dairy cows. Cows were bred by timed artificial insemination (TAI) using nonsorted semen or X-sorted sperm, or they received a fresh embryo produced in vitro by fertilization with X-sorted or nonsorted sperm using timed embryo transfer (TET). Pregnancy rates at approximately Day 32 averaged over all dairies were 39.3 ± 3.2% (least-squares mean ± SEM) for TAI nonsorted, 27.3 ± 3.4% for TET nonsorted fresh embryos, and 30.2 ± 3.3% for TET X-sorted fresh embryos (TAI vs. both TET groups, P < 0.05; 206 to 233 cows per group). Pregnancy losses between approximately Day 32 and term ranged from 16% to 37%, the latter from TET with X-sorted sperm. Pregnancy losses to term were higher for cows receiving embryos produced in vitro than for cows bred by TAI. Calves produced via TET were not substantively different from AI controls in physical measurements or standard blood chemistry profiles.


Subject(s)
Cattle , Embryo Transfer/veterinary , Fertilization in Vitro/veterinary , Lactation , Spermatozoa , Abortion, Veterinary/epidemiology , Animals , Colorado , Female , Florida , Insemination, Artificial/veterinary , Male , Pregnancy , Pregnancy Rate , Sex Ratio
6.
Theriogenology ; 74(7): 1288-95, 2010 Oct 15.
Article in English | MEDLINE | ID: mdl-20688372

ABSTRACT

The objective of this study was to determine the effects of in vitro embryo production on physical development and levels of expression of mRNAs for insulin-like growth factor (IGF) ligands (IGF1, IGF2), their receptors (IGF1R, IGF2R), and IGF binding protein-2 (IGFBP2) in bovine fetuses during early gestation. In vivo embryos were recovered from superovulated Holstein cows. For production of embryos in vitro, Holstein oocytes were matured, fertilized, and subsequently cultured in M199 with 10% serum to 168 hpi. On Day 70 of gestation, fetuses (in vivo, n = 14; in vitro, n = 13) were recovered, serum samples collected, and physical measurements recorded. Semi-quantitative RT-PCR assays were used to determine the levels of expression of mRNAs for IGF1, IGF2, IGF1R, and IGF2R in fetal liver and skeletal muscle. Western blots were used to assess levels of IGFBP2 in fetal serum. Fetal body weight did not differ with treatment; however, production of embryos in vitro was associated with decreased crown-nose length and a tendency for increased paired kidney weight, which became significant when expressed on a per bodyweight basis. There was no effect of treatment on levels of IGFBP2 in fetal serum. Levels of IGF1 mRNA in fetal liver were decreased (P < 0.001) in the in vitro group. Levels of IGF2R mRNA in both liver and skeletal muscle were also decreased (P < 0.01) in fetuses from the in vitro group. In summary, fetuses at Day 70 of gestation from embryos produced in vitro had shortened crown-nose length and increased kidney weight on a per bodyweight basis, as well as decreased expression of mRNAs for IGF1 in liver and IGF2R in both liver and skeletal muscle, compared with fetuses from embryos produced in vivo. In conclusion, in vitro embryo culture was associated with subtle changes in fetal development as well as altered expression of both imprinted and non-imprinted genes.


Subject(s)
Fertilization in Vitro/veterinary , Fetus/metabolism , Gene Expression Regulation, Developmental/physiology , RNA, Messenger/metabolism , Somatomedins/metabolism , Animals , Cattle , Female , Liver/metabolism , Male , Muscle, Skeletal/metabolism , Pregnancy , RNA, Messenger/genetics , Receptor, IGF Type 1/genetics , Receptor, IGF Type 1/metabolism , Receptor, IGF Type 2/genetics , Receptor, IGF Type 2/metabolism , Somatomedins/genetics
7.
Reprod Fertil Dev ; 22(1): 75-87, 2010.
Article in English | MEDLINE | ID: mdl-20003848

ABSTRACT

Development of the post-hatching conceptus in ruminants involves a period of morphological expansion that is driven by complex interactions between the conceptus and its intrauterine environment. As a result of these interactions, endometrial physiology is altered, leading to establishment of the pregnancy and continued development of the placenta. Disruption of normal fetal and placental development can occur when embryos are exposed to manipulations in vitro or when inappropriate endocrine sequencing occurs in vivo during the pre- and peri-implantation periods. The present review addresses the development of the post-hatching bovine conceptus, its interactions with the maternal system and changes in development that can occur as a result of in vivo and in vitro manipulations of the bovine embryo.


Subject(s)
Cattle/physiology , Congenital Abnormalities/veterinary , Pregnancy, Animal/physiology , Animals , Congenital Abnormalities/genetics , Embryonic Development/genetics , Embryonic Development/physiology , Female , Insulin-Like Growth Factor II/genetics , Insulin-Like Growth Factor II/physiology , Pregnancy , Pregnancy, Animal/genetics , RNA, Antisense/genetics , RNA, Antisense/physiology , Receptors, Somatomedin/genetics , Receptors, Somatomedin/physiology , Syndrome , Uterus/physiology
8.
J Anim Sci ; 82 E-Suppl: E53-62, 2004.
Article in English | MEDLINE | ID: mdl-15471815

ABSTRACT

The establishment of in vitro fertilization and culture systems for mammalian embryos has facilitated the application of embryo technologies in research, industry, and clinical settings. Furthermore, the advent of cloning by nuclear transfer has significantly enhanced the potential for genetic modification of livestock. Based on studies in cattle, sheep, and mice, it has become apparent that embryos produced using these systems can differ in morphology and developmental potential compared with embryos produced in vivo. Referred to as "large offspring syndrome," these abnormalities in the development of fetuses, placentas, and offspring are particularly evident following transfer of cloned embryos, but they also occur in pregnancies from embryos produced using in vitro culture alone. The objective of this review is to examine the effects of in vitro production and cloning on bovine embryo and fetal development. Literature pertaining to preimplantation embryo, conceptus, and fetal development, as well as gene expression occurring at each of these three stages, is reviewed. Physiologic and genetic mechanisms that contribute to large offspring syndrome also are discussed.


Subject(s)
Cattle/embryology , Cloning, Organism/veterinary , Embryo Culture Techniques/veterinary , Embryo Transfer/veterinary , Fertilization in Vitro/veterinary , Fetal Development/physiology , Animals , Cattle/genetics , Cattle/growth & development , Cloning, Organism/adverse effects , Embryo Transfer/adverse effects , Embryonic Development/genetics , Embryonic Development/physiology , Female , Fertilization in Vitro/adverse effects , Fetal Development/genetics , Gene Expression Regulation, Developmental/physiology , Male , Pregnancy
9.
Biol Reprod ; 64(5): 1375-85, 2001 May.
Article in English | MEDLINE | ID: mdl-11319141

ABSTRACT

The objective of this study was to compare the ultrastructure of bovine blastocysts produced in vivo or in vitro by using morphometric analysis. Blastocysts produced in vivo (multiple ovulations, MO) were obtained from superovulated Holstein cows. For blastocysts produced in vitro, cumulus-oocyte complexes aspirated from ovaries of Holstein cows were matured and fertilized in vitro. At 20 h postinsemination (hpi), zygotes were distributed into one of three culture media: 1) IVPS (in vitro produced with serum): TCM-199 + 10% estrous cow serum (ECS); 2) IVPSR (in vitro produced with serum restriction): TCM-199 + 1% BSA until 72 hpi, followed by TCM-199 + 10% ECS from 72 to 168 hpi; and 3) mSOF (modified synthetic oviductal fluid): mSOF + 0.6% BSA. At 168 hpi, six or seven grade 1 blastocysts from each of the four treatments (MO, IVPS, IVPSR, and mSOF) were fixed and prepared for transmission electron microscopy. Random micrographs of each blastocyst were used to determine the volume density of cellular components. Overall, as blastocysts progressed in development, the volume densities of cytoplasm and intercellular space decreased (P < 0.05) and the volume densities of mature mitochondria, nuclei, blastocoele, and apoptotic bodies increased (P < 0.05). Across treatments, the proportional volumes of nuclei and inclusion bodies were increased in inner cell mass cells compared with trophectoderm cells for mid- and expanded blastocysts. For blastocysts produced in vitro, the volume density of mitochondria was decreased (P < 0.05) as compared with that of blastocycts produced in vivo. The proportional volume of vacuoles was increased (P < 0.05) in blastocysts from the mSOF treatment as compared with blastocysts produced in vivo. For mid- and expanded blastocysts from all three in vitro treatments, the volume density of lipid increased (P < 0.05) and the volume density of nuclei decreased (P < 0.05) compared with those of blastocysts produced in vivo. In conclusion, blastocysts produced in vitro possessed deviations in volume densities of organelles associated with cellular metabolism as well as deviations associated with altered embryonic differentiation. However, the specific nature of these deviations varied with the type of culture conditions used for in vitro embryo production.


Subject(s)
Blastocyst/ultrastructure , Cattle/embryology , Fertilization in Vitro/veterinary , Animals , Apoptosis , Blastomeres/ultrastructure , Cell Nucleus/ultrastructure , Culture Media , Culture Techniques , Cytoplasm/ultrastructure , Microscopy, Electron , Mitochondria/ultrastructure , Superovulation , Vacuoles/ultrastructure
10.
Theriogenology ; 55(3): 805-21, 2001 Feb 01.
Article in English | MEDLINE | ID: mdl-11245267

ABSTRACT

The objective of this study was to compare the effects of administration of a single injection of progesterone (P4) and follicle aspiration on Day 7 of the estrous cycle on the timing and synchrony of follicular wave emergence, time of ovulation, and concentrations of P4, estradiol and FSH in Holstein cows. Twenty cows were assigned to 4 groups (n=5 cows per group) in a 2 by 2 factorial arrangement. Cows were treated on Day 7 (Day 0 = estrus) of the estrous cycle with either sham follicular aspiration and an oil vehicle administered intramuscularly (control), aspiration of ovarian follicles (aspiration), 200 mg of P4 im, or aspiration and 200 mg of P4 im (aspiration + P4). On Day 11, PGF(2alpha)(25mg) was administered to all groups. Synchrony of ovulation was less variable in each of the treatment groups compared with the control group (P<0.05), whereas ovulation was delayed in cows in the P4 group (P<0.05). Day of follicular wave emergence was delayed in the cows of the P4 group compared with cows in the aspiration and aspiration + P4 groups (P<0.01), whereas variability in wave emergence was less among both groups of aspirated cows compared with the cows in the control group (P<0.01). More follicles 4 to 7 mm in diameter were detected in the 2 aspiration groups compared with the cows in the control and P4 group (P<0.05). No difference was detected among groups in the maximum concentration of FSH associated with follicular wave emergence. We conclude that both the administration of P4 and the aspiration of follicles on Day 7 of the estrous cycle improves the synchrony of ovulation when luteolysis is induced on Day 11 and results in similar concentrations of FSH at the time of follicular wave emergence, but the timing of wave emergence and the number of follicles post-emergence differ.


Subject(s)
Cattle/physiology , Ovarian Follicle/growth & development , Progesterone/pharmacology , Animals , Biopsy, Needle/veterinary , Dinoprost/pharmacology , Estradiol/blood , Estrus , Estrus Synchronization/blood , Female , Follicle Stimulating Hormone/blood , Ovarian Follicle/drug effects , Ovary/diagnostic imaging , Ovulation , Ultrasonography
11.
Theriogenology ; 55(1): 151-70, 2001 Jan 01.
Article in English | MEDLINE | ID: mdl-11198080

ABSTRACT

In vitro systems are commonly used for the production of bovine embryos. Comparisons between in vivo and in vitro produced embryos illustrate that the morphology of preimplantation-stage embryos differ significantly, the survival of embryos and fetuses is decreased, the size distributions of the populations of conceptuses and fetuses are altered throughout gestation, and placental development is significantly changed. Taken together these findings indicate that exposure to some in vitro environments during the first 7 days of life can profoundly influence fetal and placental development in cattle. An understanding of how in vitro oocyte maturation, in vitro fertilization, and embryo culture systems influence both fetal and placental development should result in systems that consistently produce normal embryos, fetuses, and calves.


Subject(s)
Cattle/embryology , Embryo, Mammalian/physiology , Embryonic and Fetal Development , Fertilization in Vitro/veterinary , Animals , Culture Techniques , Embryo Transfer/veterinary , Embryo, Mammalian/ultrastructure , Female , Pregnancy
12.
Biol Reprod ; 62(5): 1459-65, 2000 May.
Article in English | MEDLINE | ID: mdl-10775201

ABSTRACT

The objective of this study was to compare the ultrastructure of bovine compact morulae produced in vivo or in vitro using morphometric analysis. Compact morulae produced in vivo were obtained from superovulated Holstein cows. Compact morulae produced in vitro were obtained from cumulus-oocyte complexes aspirated from ovaries of Holstein cows. The complexes were matured and fertilized in vitro. At 20 h postinsemination (hpi), zygotes were distributed into 1 of 3 culture media: 1) IVPS (in vitro produced with serum): TCM-199 + 10% estrous cow serum (ECS); 2) IVPSR (in vitro produced with serum restriction): TCM-199 + 1% BSA until 72 hpi followed by TCM-199 + 10% ECS from 72 to 144 hpi; 3) mSOF (modified synthetic oviductal fluid): SOF + 0.6% BSA. At 144 hpi, five grade 1 compact morulae from each of the four treatments were prepared for transmission electron microscopy. The volume density occupied by cellular components was determined by the point-count method using a sampling of seven to nine random micrographs from each compact morula. The volume density of lipid was greater (P < 0.05) in compact morulae from IVPS, IVPSR, and mSOF treatments compared with those produced in vivo. There was a reduced proportional volume of total mitochondria in compact morulae from the IVPS treatment compared with those produced in vivo (P < 0.05). For compact morulae from the IVPS culture treatment, the volume density of vacuoles was greater than that for compact morulae produced in vivo (P < 0.05). The cytoplasmic-to-nuclear ratio for compact morulae from the IVPS treatment was increased (P < 0.05) compared with the ratio for those produced in vivo. In conclusion, compact morulae produced in vitro differed ultrastructurally from those produced in vivo. Compact morulae produced in IVPS culture medium possessed the greatest deviations in cellular ultrastructure.


Subject(s)
Morula/ultrastructure , Animals , Cattle , Cell Culture Techniques/methods , Cytoplasm , Female , Fertilization in Vitro , Morula/cytology
13.
Biol Reprod ; 62(2): 384-9, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10642577

ABSTRACT

The objective of this study was to determine the effect of embryo production systems on the expression of insulin-like growth factor (IGF)-II mRNA in fetal bovine tissues at Day 70 of gestation (63 days after transfer). Oocytes aspirated from ovaries of Holstein cows were matured and fertilized in vitro. Zygotes were cultured in either tissue culture medium (TCM)-199 + 10% estrous cow serum (ECS; in vitro-produced with serum [IVPS]) or TCM-199 + 1% BSA (in vitro-produced with serum restriction [IVPSR]). At 72 h postinsemination, IVPSR embryos were transferred into fresh TCM-199 + 10% ECS whereas IVPS embryos had fresh medium replaced. All embryos were cultured for an additional 96 h. In vivo-produced embryos were harvested from superovulated Holstein cows (multiple ovulations [MO]). Grade 1 blastocysts from all groups were transferred singly into Angus heifers. At Day 70 of gestation, fetuses (n = 14, 13, and 11 for MO, IVPS, and IVPSR, respectively) were collected; liver and skeletal muscle samples were snap frozen, and whole-cell RNA (wcRNA) was extracted. Levels of IGF-II mRNA were determined by RNase protection assay and quantified relative to 18S rRNA (mean arbitrary units +/- SEM). WcRNA from adult and Day 90 fetal bovine liver were used as controls. Adult liver contained 9-fold less IGF-II mRNA than liver from Day 90 fetuses (P < 0.05). Fetal livers of males originating from IVPS and IVPSR groups possessed approximately 2-fold greater levels of mRNA for IGF-II than those from MO males (0.25 +/- 0.07, 0.33 +/- 0.04, and 0.14 +/- 0.03, respectively; P < 0.05). Levels of mRNA for IGF-II tended to be lower (P = 0.07) in skeletal muscle of fetuses originating from the IVPSR group (0.043 +/- 0.005) compared to MO controls (0.070 +/- 0.008). In conclusion, at Day 70 of gestation, fetuses originating from in vitro production systems possessed altered levels of IGF-II mRNA in both liver and skeletal muscle.


Subject(s)
Embryo Transfer , Embryo, Mammalian/metabolism , Fertilization in Vitro , Fetus/metabolism , Insulin-Like Growth Factor II/biosynthesis , RNA, Messenger/biosynthesis , Animals , Cattle , Female , Gestational Age , In Vitro Techniques , Liver/metabolism , Muscle, Skeletal/metabolism , Pregnancy , RNA, Ribosomal/biosynthesis , Ribonucleases/analysis
14.
Cloning ; 2(2): 79-90, 2000.
Article in English | MEDLINE | ID: mdl-16218862

ABSTRACT

Approximately 100 species become extinct a day. Despite increasing interest in using cloning to rescue endangered species, successful interspecies nuclear transfer has not been previously described, and only a few reports of in vitro embryo formation exist. Here we show that interspecies nuclear transfer can be used to clone an endangered species with normal karyotypic and phenotypic development through implantation and the late stages of fetal growth. Somatic cells from a gaur bull (Bos gaurus), a large wild ox on the verge of extinction, (Species Survival Plan < 100 animals) were electrofused with enucleated oocytes from domestic cows. Twelve percent of the reconstructed oocytes developed to the blastocyst stage, and 18% of these embryos developed to the fetal stage when transferred to surrogate mothers. Three of the fetuses were electively removed at days 46 to 54 of gestation, and two continued gestation longer than 180 (ongoing) and 200 days, respectively. Microsatellite marker and cytogenetic analyses confirmed that the nuclear genome of the cloned animals was gaurus in origin. The gaur nuclei were shown to direct normal fetal development, with differentiation into complex tissue and organs, even though the mitochondrial DNA (mtDNA) within all the tissue types evaluated was derived exclusively from the recipient bovine oocytes. These results suggest that somatic cell cloning methods could be used to restore endangered, or even extinct, species and populations.


Subject(s)
Cloning, Organism/methods , Embryo Culture Techniques/methods , Embryo Transfer/veterinary , Nuclear Transfer Techniques , Alleles , Animals , Cattle , Cell Line , Chromosomes/ultrastructure , Cloning, Molecular , Cytogenetics , DNA, Mitochondrial/genetics , DNA, Mitochondrial/metabolism , Electrophoresis, Agar Gel , Embryo, Mammalian/pathology , Ethidium/pharmacology , Fertilization in Vitro , Fibroblasts/metabolism , Genetic Techniques , Karyotyping , Microsatellite Repeats , Oocytes/cytology , Phenotype , Polymerase Chain Reaction , Species Specificity , Time Factors , Transplantation, Heterologous , Ultrasonography, Prenatal
15.
Theriogenology ; 52(5): 815-26, 1999 Oct 01.
Article in English | MEDLINE | ID: mdl-10735122

ABSTRACT

An unusual case of a live Holstein freemartin calf co-twinned with schistosomus reflexus fetus is presented here. Delivery of the schistosomus reflexus was achieved by fetotomy 24 h after manual delivery of a live heifer calf. The dam subsequently experienced concurrent metritis and left displacement of the abomasum; however, she conceived following insemination 85 d post partum. Cytogenetic examination of the live heifer using lymphocyte culture and cutaneous fibroblast cell culture failed to demonstrate chromosomal chimerism, whereas polymerase chain reaction (PCR) detected the presence of the bovine Y-chromosome marker BRY-1. Low concentrations of testosterone, estradiol and progesterone at 3, 6, 24 and 48 h after administration of hCG were detected in the serum of the freemartin heifer. Genetic, hormonal, histological and clinical findings established the live female co-twin calf was a freemartin, an abnormality of phenotypic sex. Failure to detect any significant peripheral concentrations of androgen supports the hypothesis that masculinization of the freemartin reproductive tract arises from diffusion of androgen and possibly other substances from the male co-twin rather than from endogenous production of androgen within the freemartin. This report documents that the freemartin condition can be induced by a male fetus with severe developmental abnormalities.


Subject(s)
Abdomen/abnormalities , Congenital Abnormalities/veterinary , Freemartinism/diagnosis , Animals , Cattle , Cattle Diseases/pathology , Cells, Cultured , Chorionic Gonadotropin , Congenital Abnormalities/pathology , Estradiol/blood , Female , Freemartinism/blood , Freemartinism/pathology , Lymphocytes/pathology , Male , Progesterone/blood , Testosterone/blood , Twins , Y Chromosome
16.
Theriogenology ; 52(4): 659-70, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10734364

ABSTRACT

The objective of this study was to estimate the degree of variation among experienced evaluators selecting in vivo- or in vitro-produced embryos for transfer and to determine how this affects both the proportion of recipients becoming pregnant after transfer, and the number of embryo transfers required per pregnancy. Data from 6 experienced evaluators who graded Day 7 embryos produced either in vivo (n = 15) or in vitro (n = 15) were used to estimate these effects. The evaluators viewed video recorded images of the embryos and classified each embryo for stage of development and quality grade (1 = excellent, 2 = good, 3 = fair, 4 = degenerated and nontransferable). The statistical model considered transfer of embryos of the following individual or combined grades: Grade 1 only, Grade 2 only, Grade 3 only, Grades 1 and 2, Grades 2 and 3, and Grades 1, 2 and 3. Probabilities of pregnancy after embryo transfer were based on pregnancy rates of recipients at the facility of 1 of the 6 evaluators where the percentages of heifers pregnant after the transfer of Grade 1, 2 and 3 embryos, by embryo source, were 76, 65 and 54% (in vivo), and 59, 45 and 30% (in vitro). Within most grades, the proportion of embryos selected for transfer differed (P < 0.05) among the 6 evaluators. Although no significant differences (P > 0.10) were found among evaluators in the proportion of recipients pregnant after transfer within any embryo grade, there was substantial variation among evaluators in the proportion of recipients becoming pregnant, especially for embryos produced in vitro. Estimated percentages of heifers becoming pregnant for embryos classified as Grade 1, 2 or 3 were 66 to 76, 62 to 69, and 54 to 60%, respectively, for in vivo-produced embryos; and, 39 to 59, 15 to 45, and 24 to 32%, respectively, for in vitro-produced embryos. Approximately twice as many transfers were needed per pregnancy for embryos produced in vitro as for those produced in vivo regardless of the grade.


Subject(s)
Embryo Transfer/veterinary , Fertilization in Vitro/veterinary , Pregnancy Outcome/veterinary , Animals , Cattle , Embryonic and Fetal Development , Female , Pregnancy , Probability , Video Recording
17.
Abdom Imaging ; 22(4): 401-3, 1997.
Article in English | MEDLINE | ID: mdl-9157860

ABSTRACT

We report a case of infectious thrombosis of the superior mesenteric vein (pylephlebitis) that was suspected preoperatively with computed tomography and confirmed at intraoperative ultrasonography as confined to the extrahepatic portal vein and superior mesenteric vein. Intraoperative ultrasonography revealed intraluminal echogenic thrombus material in the dilated superior mesenteric and extrahepatic portal veins, slightly dilated open splenic vein, and numerous venous collaterals in the hepatoduodenal ligament. When preoperative imaging studies are inconclusive, intraoperative sonography can confirm the correct diagnosis of pylephlebitis and may give valuable information about the extent of the thrombosis.


Subject(s)
Appendicitis/complications , Bacterial Infections/diagnostic imaging , Intraoperative Care , Phlebitis/microbiology , Portal Vein/diagnostic imaging , Thrombosis/microbiology , Ultrasonography, Interventional , Adult , Appendicitis/microbiology , Collateral Circulation , Dilatation, Pathologic/diagnostic imaging , Humans , Ligaments/blood supply , Ligaments/diagnostic imaging , Male , Mesenteric Vascular Occlusion/diagnostic imaging , Mesenteric Vascular Occlusion/microbiology , Mesenteric Veins/diagnostic imaging , Phlebitis/diagnostic imaging , Splenic Vein/diagnostic imaging , Splenic Vein/microbiology , Thrombosis/diagnostic imaging
18.
Abdom Imaging ; 22(3): 261-3, 1997.
Article in English | MEDLINE | ID: mdl-9107646

ABSTRACT

We present a case of intraperitoneal seeding in a 36-year-old woman with a large primary hepatocellular carcinoma located superfically in the left lobe of the otherwise normal liver. The patient was treated with percutaneous ethanol ablation therapy. Eight months after the treatment computed tomography and ultrasonography (US) revealed an intraperitoneal seeding that was confirmed with US-guided percutaneous biopsy.


Subject(s)
Carcinoma, Hepatocellular/secondary , Carcinoma, Hepatocellular/therapy , Ethanol/therapeutic use , Liver Neoplasms/therapy , Neoplasm Seeding , Peritoneal Neoplasms/secondary , Adult , Carcinoma, Hepatocellular/diagnosis , Ethanol/administration & dosage , Female , Humans , Peritoneal Neoplasms/diagnosis , Peritoneal Neoplasms/etiology
19.
Eur Radiol ; 7(2): 262-3, 1997.
Article in English | MEDLINE | ID: mdl-9038128

ABSTRACT

An intragastric blood clot suggested by sonography and later confirmed at upper gastrointestinal series and at gastroscopy is reported. Sonographic findings were a moveable mass within stomach presenting as an arc-like hyperechoic surface with a strong posterior resonance artifact. Compression of the mass with a transducer induced the mass to move from antrum to corpus within stomach. We think that the demonstration of a blood clot within stomach can be suggested on the basis of typical sonographic findings as a secondary sign of a bleeded gastric or duodenal ulcer.


Subject(s)
Peptic Ulcer Hemorrhage/diagnostic imaging , Stomach Ulcer/diagnostic imaging , Stomach/diagnostic imaging , Aged , Blood Coagulation , Female , Humans , Peptic Ulcer Hemorrhage/etiology , Stomach Ulcer/complications , Ultrasonography
20.
Am J Epidemiol ; 144(8): 742-8, 1996 Oct 15.
Article in English | MEDLINE | ID: mdl-8857823

ABSTRACT

The aim of this 8-year follow-up study was to investigate the role of conventional cardiovascular risk factors as predictors for asymptomatic femoral atherosclerosis. The authors also evaluated the association of insulin resistance with atherosclerosis in a cross-sectional setting. Cardiovascular risk factors of 118 subjects were studied at the baseline study in 1983-1985 in Kuopio, Finland. Femoral atherosclerosis, defined as a presence of plaques, was investigated by ultrasonography in the follow-up study in 1992-1993. In the univariate logistic regression analyses, age (p = 0.002), systolic and diastolic blood pressure (p = 0.002 and p = 0.013, respectively), total cholesterol (p = 0.005), low density lipoprotein (LDL) cholesterol (p = 0.005), total triglycerides (p = 0.033), LDL triglycerides (p = 0.033), apolipoprotein B (p = 0.045), and fasting plasma glucose (p = 0.011) had a significant association with the presence of femoral plaques. Plasma insulin levels and insulin sensitivity index, determined in 87 subjects by an intravenous glucose tolerance test and minimal model at the follow-up study, were not associated with femoral plaques. The results demonstrate that atherogenic lipid and lipoprotein pattern and blood pressure are strongly associated with femoral atherosclerosis, whereas insulin sensitivity and hyperinsulinemia seem not to play such a significant role.


Subject(s)
Arteriosclerosis/etiology , Femoral Artery/diagnostic imaging , Insulin Resistance , Adult , Aged , Aged, 80 and over , Arteriosclerosis/diagnostic imaging , Blood Glucose , Blood Pressure , Cross-Sectional Studies , Female , Follow-Up Studies , Humans , Insulin/blood , Lipids/blood , Male , Middle Aged , Predictive Value of Tests , Regression Analysis , Risk Factors , Ultrasonography
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