Increased expression of pro-inflammatory cytokines at the fetal-maternal interface in bovine pregnancies produced by cloning.

Problem: A significant rate of spontaneous abortion is observed in cattle pregnancies produced by somatic cell nuclear transfer (SCNT). Major histocompatibility complex class I (MHC-I) proteins are abnormally expressed on the surface of trophoblast cells from SCNT conceptuses.

Method Of Study: MHC-I homozygous compatible (n = 9), homozygous incompatible (n = 8), and heterozygous incompatible (n = 5) pregnancies were established by SCNT.

Genetic and epigenetic regulation of major histocompatibility complex class I gene expression in bovine trophoblast cells.

Problem: The regulatory mechanisms governing differential expression of classical major histocompatibility complex (MHC) class I (MHC-Ia) and non-classical MHC class I (MHC-Ib) genes are poorly understood.

Method Of Study: Quantitative reverse transcription- polymerase chain reaction (PCR) was used to compare the abundance of MHC-I transcripts and related transcription factors in peripheral blood mononuclear cells (PBMC) and placental trophoblast cells (PTC). Methylation of MHC-I CpG islands was detected by bisulfite treatment and next-generation sequencing.

Single-Incision Carpal Tunnel Release and Distal Radius Open Reduction and Internal Fixation: A Cadaveric Study.

Background: The safety of surgical approaches for single- versus double-incision carpal tunnel release in association with distal radius open reduction and internal fixation remains controversial.

Purpose: The purpose of this study was to identify critical structures to determine if a single-incision extension of the standard flexor carpi radialis (FCR) approach can be performed safely.

Methods: Nine cadaveric arms with were dissected under loupe magnification, utilizing a standard FCR approach.

Trophoblast Major Histocompatibility Complex Class I Expression Is Associated with Immune-Mediated Rejection of Bovine Fetuses Produced by Cloning.

Trophoblast cells from bovine somatic cell nuclear transfer (SCNT) conceptuses express major histocompatibility complex class I (MHC-I) proteins early in gestation, and this may be one cause of the significant first-trimester embryonic mortality observed in these pregnancies. MHC-I homozygous-compatible (n = 9), homozygous-incompatible (n = 8), and heterozygous-incompatible (n = 5) SCNT pregnancies were established. The control group consisted of eight pregnancies produced by artificial insemination.

DNA methylation of the LIN28 pseudogene family.

Background: DNA methylation directs the epigenetic silencing of selected regions of DNA, including the regulation of pseudogenes, and is widespread throughout the genome. Pseudogenes are decayed copies of duplicated genes that have spread throughout the genome by transposition. Pseudogenes are transcriptionally silenced by DNA methylation, but little is known about how pseudogenes are targeted for methylation or how methylation levels are maintained in different tissues.

Drosophila muller f elements maintain a distinct set of genomic properties over 40 million years of evolution.

The Muller F element (4.2 Mb, ~80 protein-coding genes) is an unusual autosome of Drosophila melanogaster; it is mostly heterochromatic with a low recombination rate. To investigate how these properties impact the evolution of repeats and genes, we manually improved the sequence and annotated the genes on the D.

Development of a modified straw method for vitrification of in vitro-produced bovine blastocysts and various genes expression in between the methods.

This study evaluated a modified plastic straw loading method for vitrification of in vitro-produced bovine blastocysts. A modified straw was used with a depressed area on its inner surface to which embryos attach. In vitro-produced blastocysts were randomly assigned into three groups: (i) blastocysts attached to the inner surface of a plastic straw (aV), (ii) blastocysts attached to the inner surface of a modified plastic straw (maV), and (iii) non-vitrified blastocysts (control).

Louisiana physician population trends: will increase in supply meet demand?

Physician shortages in the United States are now recognized broadly and widespread by specialty and geography. While supply is increasing, demand inexorably rises. This situation will probably be further stressed post implementation of healthcare reform.

Enucleation of demecolcine-treated bovine oocytes in cytochalasin-free medium: mechanism investigation and practical improvement.

Demecolcine-assisted/induced enucleation has been used in nuclear transfer cloning procedures for many species, yet its mechanism of action remains unclear. Primarily because oocytoplasm protrusion induced by demecolcine is inhibited by the presence of cytochalasin, its use has had limited application. In this experiment, we investigated the microtubule and microfilament alterations in bovine oocytes after demecolcine and/or cytochalasin B (CB) treatments by immunocytochemical staining.

Oolemma receptors and oocyte activation.

At fertilization the sperm triggers a series of intracellular calcium oscillations that are pivotal to oocyte activation and development. Although the biological significance of the characteristic intracellular calcium (Ca(2+)(i)) oscillations is not fully understood, calcium ions are known to be involved in cortical granule release and in controlling cell cycle progression. Two different hypotheses attempt to explain how sperm initiate (Ca(2+)(i)) oscillations in mammalian oocytes.

Abnormal levels of transcript abundance of developmentally important genes in various stages of preimplantation bovine somatic cell nuclear transfer embryos.

Based on microarray data comparing gene expression of fibroblast donor cells and bovine somatic cell nuclear transfer (SCNT) and in vivo produced (AI) blastocysts, a group of genes including several transcription factors was selected for evaluation of transcript abundance. Using SYBR green-based real-time polymerase chain reaction (Q-PCR) the levels of POU domain class 5 transcription factor (Oct4), snail homolog 2 (Snai2), annexin A1 (Anxa1), thrombospondin (Thbs), tumor-associated calcium signal transducer 1 (Tacstd1), and transcription factor AP2 gamma (Tfap2c) were evaluated in bovine fibroblasts, oocytes, embryos 30 min postfusion (SCNT), 12 h postfertilization/activation, as well as two-cell, four-cell, eight-cell, morula, and blastocyst-stage in vitro fertilized (IVF) and SCNT embryos. For every gene except Oct4, levels of transcript were indistinguishable between IVF and SCNT embryos at the blastocyst stage; however, in many cases levels of these genes during stages prior to blastocyst differed significantly.

Colcemid-treatment of heifer oocytes enhances nuclear transfer embryonic development, establishment of pregnancy and development to term.

Four experiments were designed to examine the effects of colcemid, a microtubule assembly inhibitor, on the development of bovine nuclear transfer (NT) embryos in vitro and in vivo. Recipient oocytes matured at different times were exposed to colcemid. Approximately 80-93% of the exposed oocytes, with or without the first polar body (PB1), developed obvious membrane projections.

Global gene expression analysis of bovine somatic cell nuclear transfer blastocysts and cotyledons.

Low developmental competence of bovine somatic cell nuclear transfer (SCNT) embryos is a universal problem. Abnormal placentation has been commonly reported in SCNT pregnancies from a number of species. The present study employed Affymetrix bovine expression microarrays to examine global gene expression patterns of SCNT and in vivo produced (AI) blastocysts as well as cotyledons from day-70 SCNT and AI pregnancies.

Nicotine combined with okadaic acid or taxol adversely affects bovine oocyte maturation and subsequent embryo development.

Objective: To investigate the effects of nicotine in combination with okadaic acid (OA) or taxol on bovine oocyte maturation and subsequent embryonic development.

Design: Prospective randomized study.

Setting: University research laboratory.

A novel approach to identify bovine sperm membrane proteins that interact with receptors on the vitelline membrane of bovine oocytes.

At fertilization, the sperm triggers intracellular calcium oscillations, which are pivotal to oocyte activation and development. A working hypothesis for the interaction between the sperm and the oocyte is that disintegrin ligands on the inner acrosomal membrane of the sperm bind to integrin receptors on the oocyte vitelline membrane. The aim of these experiments was to find and identify the sperm protein ligands involved in bovine sperm-oocyte interactions.

Nicotine alters bovine oocyte meiosis and affects subsequent embryonic development.

The effects of nicotine on nuclear maturation and meiotic spindle dynamics of bovine oocytes and subsequent embryonic development were investigated. Maturation rates (85%-94%) derived from nicotine treatments at 0.01 to 1.

Effect of nicotine on in vitro maturation of bovine oocytes.

The putative effect of nicotine on maturation and the chromosomal complement of bovine oocytes were investigated in the present study. Cumulus-enclosed oocytes were incubated in maturation medium with 0, 0.5, 1.

Forecasting change in Louisiana physician age cohorts: 1994-2020.

A shortage of physicians is predicted in the near future, as there is a mismatch between the supply and demand for physicians. Our objective was to examine what effect an aging Louisiana physician population might have on these forecasts using data from the American Medical Association and population projections from the Louisiana Population Data Center. Our results propose a considerable rise in the number of Louisiana physicians who are older, with growth in younger physicians being continually flat.

Effects of amino acid substitutions in and around the arginine-glycine-aspartic acid (RGD) sequence on fertilization and parthenogenetic development in mature bovine oocytes.

Integrins have been shown to be involved in the process of fertilization and many integrin-ligand interactions are mediated through the recognition of an arginine-glycine-aspartic acid (RGD) sequence. Despite the fact the RGD domain is a principal player in determining the functional characteristics of an adhesive protein, increasing evidence has accumulated implicating the amino acids flanking the RGD sequence in determining the functional properties of the RGD-containing protein. A set of linear peptides in which the amino acid sequence in and around the RGD tri-peptide was modified was synthesized to better understand the specificity of the RGD-receptor interaction.

Denuding and centrifugation of maturing bovine oocytes alters oocyte spindle integrity and the ability of cytoplasm to support parthenogenetic and nuclear transfer embryo development.

The effects of cumulus cell removal and centrifugation of maturing bovine oocytes on nuclear maturation and subsequent embryo development after parthenogenetic activation and nuclear transfer were examined. Removal of cumulus cells at 4, 8, and 15 hr after in vitro maturation (IVM) or the centrifugation of denuded oocytes had no effect on maturation rates. Oocytes treated at 0 hr of IVM had a lower expulsion rate (50%) of the first polar body (PB1).

Effect of the time interval between fusion and activation on nuclear state and development in vitro and in vivo of bovine somatic cell nuclear transfer embryos.

This study indicated that prolonged exposure of donor cell nuclei to oocyte cytoplasm before activation results in abnormal chromatin morphology, and reduced development to compacted morula/blastocyst stage in vitro. However, after transfer of embryos to recipients, there was no difference in pregnancy rates throughout gestation. Chromatin morphology was evaluated for embryos held 2, 3, 4 and 5 h between fusion and activation.

The developmental competence of bovine nuclear transfer embryos derived from cow versus heifer cytoplasts.

Due to its economic importance, the production of cattle by nuclear transfer has been a primary research focus for many researchers during the past few years. While many groups have successfully produced cattle by nuclear transfer, and progress in this area continues, nuclear transfer remains a very inefficient technology. This study evaluates the effect of the oocyte source (cow and heifer) on the developmental competence of nuclear transfer embryos.

Development, chromosomal composition, and cell allocation of bovine cloned blastocyst derived from chemically assisted enucleation and cultured in conditioned media.

Treatment of in vitro matured bovine oocytes with colcemid results in a membrane protrusion that contains maternal chromosomes, which can be easily removed by aspiration. Four experiments were designed to evaluate the overall and temporal effects of conditioned medium (CM) by bovine cumulus cells on development of nuclear transfer (NT) bovine embryos and to examine the chromosomal composition and allocation of inner cell mass (ICM) and trophectoderm (TE) of the subsequent blastocysts. The nuclear transfer embryos were cultured in various CR1aa media conditioned by preculture with bovine cumulus cells.