Parthenogenetic development of mouse embryos in vivo

Development ◽  
1973 ◽  
Vol 30 (3) ◽  
pp. 547-560
Author(s):  
Anna Witkowska
Keyword(s):  
Electric Shock ◽  
Implantation Rate ◽  
Mouse Embryos ◽  
Somite Stage ◽  
Advanced Embryo ◽  
Parthenogenetic Development ◽  
Implantation Sites ◽  
The Mean

CBA-p and CBA-T6T6 females were mated with vasectomized males of A strain and early in the morning the eggs were activated in situ with the electric shock of 30, 40 and 50 V. Females were killed between the 5th and the 10th day of pregnancy and the implantation sites were studied histologically or their content was examined under the dissecting microscope. Of the uterine horns, 43·6% contained at least one implantation and the mean number of implantations per horn was 0·76. Altogether 152 implantations were collected. The implantation rate was twice as high in older females (12 weeks and over) as in young ones (6–8 weeks). The number of living embryos decreased with every day so that on the 9th and 10th day only 2 out of 86 embryos were alive (2·3%). With one exception all embryos which were alive at the time of examination were retarded in development for approximately 1 day. The most advanced embryo was at the 8-somite stage. Two attempts aimed at increasing the synchrony between the embryos and the uterus at the time of implantation (activation immediately after delayed mating and transfer of 4·5-day embryos to 3·5-day uterus) did not improve the survival of embryos after implantation.

Relationship between the gas production profiles of mixtures of hay and maize and the patterns of rumen fermentation observed in sheep fed those mixtures

1998 ◽  
Vol 1998 ◽  
pp. 63-63
Author(s):  
C. Rymer ◽  
D.I. Givens
Keyword(s):  
Growth Rate ◽  
Feed Intake ◽  
Rumen Fermentation ◽  
Gas Production ◽  
Post Feeding ◽  
Molar Proportion ◽  
Rumen Ph ◽  
The Mean

The gas production (GP) technique has been developed to assess dynamics of ruminant digestion. Relationships have been observed between a feed's GP profile and in vivo parameters such as digestibility (Khazaal et al., 1993), feed intake and growth rate (Blümmel and Ørskov, 1993), and in situ degradability (Sileshi et al., 1997). However, there are few studies which relate GP data to the in vivo pattern of rumen fermentation (in terms of the rate of pH decline 2 h post-feeding and the mean rumen pH, concentration of total VFA and molar proportion of individual VFA). The object of this experiment was to determine whether such a relationship existed between a feed's GP profile and the pattern of rumen fermentation observed in animals fed that feed.

scholarly journals Implantation in Coronary Circulation Induces Morphofunctional Transformation of Radial Grafts From Muscular to Elastomuscular

Circulation ◽  
2005 ◽  
Vol 112 (9_supplement) ◽  
Author(s):  
Mario Gaudino ◽  
Francesco Prati ◽  
Eugenio Caradonna ◽  
Carlo Trani ◽  
Francesco Burzotta ◽  
...  
Keyword(s):  
Internal Thoracic Artery ◽  
Coronary Circulation ◽  
Ultrasound Examination ◽  
Artery Bypass ◽  
Elastic Tissue ◽  
The Media ◽  
The Mean ◽  
Muscular Architecture

Background— The purpose of this research was to investigate the in vivo morphofunctional changes induced in the radial artery (RA) by its use as coronary artery bypass conduit by comparing the morphological features and vasoreactivity of the native RA versus the coronary RA graft in the same patient. Methods and Results— Ten years after surgery, 10 patients were submitted to intravascular ultrasound examination of the RA graft of the controlateral (in situ) RA and of the internal thoracic artery (ITA) graft and to vasoactive challenges with acetylcholine and serotonin. Quantitative angiographic assessment showed that the mean diameter of the RA coronary grafts was significantly larger than that of the in situ RA and of the ITA (2.89±0.40 mm RA grafts, 2.14±0.52 mm in situ RA, 2.25±0.53 mm ITA grafts; P <0.001). The in situ RA demonstrated a typical muscular architecture, whereas RA coronary grafts showed a clear reduction of the thickness of the medial layer and had a less well-defined muscular component of the media with interposition of elastic tissue. Serotonin endovascular infusion elicited a strong spastic reaction in in situ RAs; the same challenge induced only moderate constriction in RA and ITA coronary grafts. Conclusions— Implantation in the coronary circulation leads to major anatomic and vasoreactive modifications of the RAs that tend to lose the morphofunctional features of a muscular conduit and assume those of an elastomuscular artery, such as the ITA.

260 COMPARISON OF HOUSEKEEPING GENE EXPRESSION IN INDIVIDUAL 8-CELL STAGE MOUSE EMBRYOS PRODUCED UNDER DIFFERENT CONDITIONS

2007 ◽  
Vol 19 (1) ◽  
pp. 246
Author(s):  
A. Baji Gal ◽  
S. Mamo ◽  
S. Bodo ◽  
A. Dinnyes
Keyword(s):  
Gene Expression ◽  
Real Time ◽  
Standard Error ◽  
Real Time Pcr ◽  
Housekeeping Gene ◽  
Mouse Embryos ◽  
Cell Stage ◽  
The Mean

Real-time PCR has the potential to accurately quantify the mRNA level of selected genes in single cells and individual pre-implantation-stage embryos. The goal of our study was to examine the variations in gene expression within individual embryos of the same stage and between embryos of the same stage but from different sources. In our study, we determined expression level of the 7 most commonly used housekeeping genes in 8-cell-stage mouse embryos produced under different culture conditions. Messenger RNA of 6 embryos each that was derived in vivo, or cultured in vitro from the zygote stage, or derived from oocytes activated parthenogenetically and developed in vitro were extracted individually followed by reverse transcription into cDNA. Optimized real-time PCR was performed for cytoplasmic beta-actin (Actb), glyceraldehyde-3-phosphate dehydrogenase (Gapdh), H2A histone family, member Z (H2afz), hypoxanthine guanine phosphoribosyl transferase 1 (Hprt1), ubiquitin C (Ubc), peptidylprolyl isomerase A (cyclophilin A) (Ppia), and eukaryotic translation elongation factor 1 epsilon 1 (Eef1e1) genes. The results were analyzed, and the percentage standard error of the mean relative expression value was compared for all genes. All 7 genes were presented above the detection limit in all samples. One or two individual embryos showed 2- to 4-fold higher mRNA levels than the average for all genes in the group. The embryos cultured in vitro showed much higher expression levels of H2afz, Ppia, and Eef1e1 genes than those in the in vivo group. The parthenogenetic group was similar to the in vivo group in expression of Actb, H2afz, Hprt, and Eef1e1 genes, but showed significant differences (P &lt; 0.05; Student's t-test) compared to the in vitro group (Table 1). The percent standard error of the mean decreased gradually as the number of samples was increased. The 6 individual embryos in similar groups showed relatively low variability compared to embryos at similar stage but produced in different conditions. Interestingly, the parthenogenetic embryos showed a level of gene expression comparable to that of the in vivo ones, notwithstanding their culture in vitro. In conclusion, morphological observations and similarity in developmental stage alone cannot guarantee the uniformity of embryo samples, and a minimum of 4–6 replicates per treatment is needed. Moreover, we showed that culture condition itself has an effect on housekeeping gene expression, which, if neglected, might result in misinterpretation of data. Table 1.Relative expression values of the different culture groups (mean ±SE; n =6 embryos) This work was supported by EU FP6 (MEXT-CT-2003-509582 and 518240), Wellcome Trust (Grant No. 070246), and Hungarian National Science Fund (OTKA) (Grant No. T046171).

Thrombopoietin responsiveness reflects the number of doublings undergone by megakaryocyte progenitors

Blood ◽  
2004 ◽  
Vol 104 (8) ◽  
pp. 2291-2298 ◽  
Author(s):  
Jean-Michel Paulus ◽  
Najet Debili ◽  
Frédéric Larbret ◽  
Jack Levin ◽  
William Vainchenker
Keyword(s):  
Dose Response ◽  
Receptor Density ◽  
Response Curves ◽  
Age Model ◽  
Normal Human ◽  
The Mean ◽  
Dose Response Curves

Abstract To assess the variation of thrombopoietin (TPO) responsiveness associated with megakaryocyte (MK) progenitor amplification, TPO dose-response curves were obtained for normal human, single-cell plated CD34+CD41+ cells. The number of MKs per well was determined in situ and expressed as number of doublings (NbD). Dose-response curves of the mean frequency of clones of each size versus log TPO concentration showed highly significant differences in the TPO concentration needed for half-maximum generation of clones of different sizes (TPO50): 1.89 ± 0.51 pg/mL for 1 MK clones; 7.75 ± 0.81 pg/mL for 2 to 3 MK clones; 38.5 ± 5.04 pg/mL for 4 to 7 MK clones, and 91.8 ± 16.0 pg/mL for 8 to 15 MK clones. These results were consistent with a prediction of the generation-age model, because the number of previous doublings in vivo was inversely correlated with the number of residual doublings in vitro. TPO responsiveness decreased in vitro by a factor of 3.5 per doubling, reflecting the recruitment of progressively more ancestral progenitors. In support of this hypothesis, the more mature CD34+CD41+CD42+ cell fraction had a lower TPO50 (P &lt; .001), underwent fewer NbD (P &lt; .001), and expressed a 2.8-fold greater median Mpl receptor density (P &lt; .001) than the CD34+CD41+CD42– fraction. Progenitors that have completed their proliferative program have maximum factor responsiveness and are preferentially induced to terminal differentiation.

scholarly journals Expression and function of Pdcd4 in mouse endometrium during early pregnancy

Reproduction ◽  
2018 ◽  
Vol 155 (4) ◽  
pp. 393-402 ◽  
Author(s):  
Yue Zhang ◽  
Mingyun Ni ◽  
Na Liu ◽  
Yongjiang Zhou ◽  
Xuemei Chen ◽  
...  
Keyword(s):  
Early Pregnancy ◽  
Quantitative Polymerase Chain Reaction ◽  
Embryo Implantation ◽  
Complex Process ◽  
Programmed Cell Death 4 ◽  
Implantation Sites ◽  
And Function

Embryo implantation is a complex process involving synchronised crosstalk between a receptive endometrium and functional blastocysts. Apoptosis plays an important role in this process as well as in the maintenance of pregnancy. In this study, we analysed the expression pattern of programmed cell death 4 (Pdcd4), a gene associated with apoptosis in the mouse endometrium, during early pregnancy and pseudopregnancy by real-time quantitative polymerase chain reaction, in situ hybridisation, Western blotting and immunohistochemistry. The results showed that Pdcd4 was increased along with days of pregnancy and significantly reduced at implantation sites (IS) from day 5 of pregnancy (D5). The level of Pdcd4 at IS was substantially lower than that at interimplantation sites (IIS) on D6 and D7. In addition, Pdcd4 expression in the endometrium was reduced in response to artificially induced decidualisation in vivo and in vitro. Downregulation of Pdcd4 gene expression in cultured primary stromal cells promoted decidualisation, while upregulation inhibited the decidualisation process by increasing apoptosis. These results demonstrate that Pdcd4 is involved in stromal cell decidualisation by mediating apoptosis and therefore plays a role in embryo implantation in mice.

scholarly journals In vivo Fluorometric Measurement of Changes in Cytosolic Free Calcium from the Cat Cortex during Anoxia

1988 ◽  
Vol 8 (3) ◽  
pp. 367-374 ◽  
Author(s):  
Daisuke Uematsu ◽  
Joel H. Greenberg ◽  
Martin Reivich ◽  
Sei Kobayashi ◽  
Andrea Karp
Keyword(s):  
Intracellular Free Calcium ◽  
Ultraviolet Rays ◽  
Free Calcium ◽  
Acetoxymethyl Ester ◽  
New Approach ◽  
Electrical Failure ◽  
Electrocorticogram Ecog ◽  
The Mean

A new approach to assess the mean changes in intracellular free calcium [Ca2+]i directly from the cortex in situ is described along with the [Ca2+]i changes during nitrogen anoxia. Following incision of the dura and part of the pia-arachnoid membrane, quin2 acetoxymethyl ester, 100 μ M in artificial CSF, was superfused for 60 min onto the cat cortex. A small cortical area was irradiated with ultraviolet rays (350/30 nm) and the changes in the fluorescence and reflectance were recorded microfluorometrically at 506 and 366 nm, respectively. The net change in the quin2-Ca2+ fluorescence was calculated after correction for the hemodynamic artifact and subtraction of the basal NADH change. The quin2-Ca2+ fluorescence began to increase significantly (48.0 ± 13.4 units; p < 0.05) 20 s prior to the isoelectric electrocorticogram (ECoG) and remained elevated during nitrogen anoxia. It decreased steeply 7.3 ±1.7 s prior to the recovery of the ECoG activity after the animal was reoxygenated. Thus, the changes in the intracellular free calcium preceded those of the ECoG during a reversible anoxic insult, suggesting that the increase in the [Ca2+]i might be related to the electrical failure during anoxia.

Relationship between the gas production profiles of mixtures of hay and maize and the patterns of rumen fermentation observed in sheep fed those mixtures

1998 ◽  
Vol 1998 ◽  
pp. 63-63 ◽  
Author(s):  
C. Rymer ◽  
D.I. Givens
Keyword(s):  
Growth Rate ◽  
Feed Intake ◽  
Rumen Fermentation ◽  
Gas Production ◽  
Post Feeding ◽  
Molar Proportion ◽  
Rumen Ph ◽  
The Mean

The gas production (GP) technique has been developed to assess dynamics of ruminant digestion. Relationships have been observed between a feed's GP profile and in vivo parameters such as digestibility (Khazaal et al., 1993), feed intake and growth rate (Blümmel and Ørskov, 1993), and in situ degradability (Sileshi et al., 1997). However, there are few studies which relate GP data to the in vivo pattern of rumen fermentation (in terms of the rate of pH decline 2 h post-feeding and the mean rumen pH, concentration of total VFA and molar proportion of individual VFA). The object of this experiment was to determine whether such a relationship existed between a feed's GP profile and the pattern of rumen fermentation observed in animals fed that feed.

scholarly journals Structure of native cellulose microfibrils, the starting point for nanocellulose manufacture

2017 ◽  
Vol 376 (2112) ◽  
pp. 20170045 ◽  
Author(s):  
Michael C. Jarvis
Keyword(s):  
Higher Plants ◽  
Cellulose Microfibrils ◽  
New Horizons ◽  
Nanofibrillar Cellulose ◽  
Starting Point ◽  
Anionic Polysaccharides ◽  
Dicotyledonous Plants ◽  
The Mean

There is an emerging consensus that higher plants synthesize cellulose microfibrils that initially comprise 18 chains. However, the mean number of chains per microfibrilin situis usually greater than 18, sometimes much greater. Microfibrils from woody tissues of conifers, grasses and dicotyledonous plants, and from organs like cotton hairs, all differ in detailed structure and mean diameter. Diameters increase further when aggregated microfibrils are isolated. Because surface chains differ, the tensile properties of the cellulose may be augmented by increasing microfibril diameter. Association of microfibrils with anionic polysaccharides in primary cell walls and mucilages leads toin vivomechanisms of disaggregation that may be relevant to the preparation of nanofibrillar cellulose products. For the preparation of nanocrystalline celluloses, the key issue is the nature and axial spacing of disordered domains at which axial scission can be initiated. These disordered domains do not, as has often been suggested, take the form of large blocks occupying much of the length of the microfibril. They are more likely to be located at chain ends or at places where the microfibril has been mechanically damaged, but their structure and the reasons for their sensitivity to acid hydrolysis need better characterization.This article is part of a discussion meeting issue ‘New horizons for cellulose nanotechnology’.

Parthenogenetic development of mouse embryos in vivo

Development ◽  
1973 ◽  
Vol 30 (3) ◽  
pp. 519-545
Author(s):  
Anna Witkowska
Keyword(s):  
Polar Body ◽  
Subsequent Development ◽  
Hormonal Treatment ◽  
Inbred Strains ◽  
Early Cleavage ◽  
Parthenogenetic Development ◽  
Second Polar Body ◽  
First Time

Newly ovulated eggs from CBA-p and CBA-T6T6 inbred strains were activated in situ with an electric shock of 20–50 V. Both spontaneously ovulating females mated with vasectomized males (strain A) and those induced to ovulate and kept apart from males were used. The immediate reaction of eggs was examined 5–7 h after activation and their subsequent development was followed every day up to the 6th day (eggs examined on the 5th and 6th day were tube-locked by a ligature). In spontaneous ovulators the highest yield of activated eggs was obtained following 30 V shock (75%), with a mean for four series (20, 30, 40 and 50 V) of 46·1%. The most common reaction is extrusion of the second polar body (2 PB) and formation of one pronucleus (about 70% of activated eggs). Other types of reaction include: immediate cleavage, suppression of 2 PB with formation of two or, very rarely, one pronucleus. Thus the majority of eggs are potentially haploid. No relationship between the frequency of various types of reaction and the strength of the shock (voltage) was observed. Up to the 3rd day cleavage proceeds at a normal rate and appears to slow down during the 4th day. In spontaneously ovulating females the incidence of blastocysts among developing eggs rises from 3·4% on the 4th day to 52·5% on the 5th day; the corresponding figures for induced ovulations are 10% and 23·6%. Some embryos despite being composed of a large number of cells (40–120) do not undergo cavitation and remain morulae. On the basis of karyological examination of 60 embryos with analysable metaphase plates 60% were classified as haploid, 16·7% as diploid, 1·7% as tetraploid and 21·6% as haploid/diploid mosaics. During early cleavage binucleate blastomeres (a presumed step in regulation from n to 2n) were observed only in eggs from induced ovulations. In embryos developed from spontaneously ovulated eggs n/2n mosaics were observed for the first time on the 5th day. In general, spontaneously ovulated eggs developed better after activation (both in quantitative and qualitative terms) than those obtained following hormonal treatment.

scholarly journals Hemorrhage, Impaired Hematopoiesis, and Lethality in Mouse Embryos Carrying a Targeted Disruption of the Fli1Transcription Factor

2000 ◽  
Vol 20 (15) ◽  
pp. 5643-5652 ◽  
Author(s):  
Demetri D. Spyropoulos ◽  
Pamela N. Pharr ◽  
Kim R. Lavenburg ◽  
Pascale Jackers ◽  
Takis S. Papas ◽  
...  
Keyword(s):  
Embryonic Stem Cell Line ◽  
Embryonic Stem ◽  
Mouse Embryos ◽  
Targeted Disruption ◽  
Complete Penetrance ◽  
Ets Family ◽  
The Brain

ABSTRACT The Ets family of transcription factors have been suggested to function as key regulators of hematopoeisis. Here we describe aberrant hematopoeisis and hemorrhaging in mouse embryos homozygous for a targeted disruption in the Ets family member, Fli1. Mutant embryos are found to hemorrhage from the dorsal aorta to the lumen of the neural tube and ventricles of the brain (hematorrhachis) on embryonic day 11.0 (E11.0) and are dead by E12.5. Histological examinations and in situ hybridization reveal disorganization of columnar epithelium and the presence of hematomas within the neuroepithelium and disruption of the basement membrane lying between this and mesenchymal tissues, both of which express Fli1 at the time of hemorrhaging. Livers from mutant embryos contain few pronormoblasts and basophilic normoblasts and have drastically reduced numbers of colony forming cells. These defects occur with complete penetrance of phenotype regardless of the genetic background (inbred B6, hybrid 129/B6, or outbred CD1) or the targeted embryonic stem cell line used for the generation of knockout lines. Taken together, these results provide in vivo evidence for the role of Fli1 in the regulation of hematopoiesis and hemostasis.

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