Effect of chemical dechorionation on silkworm embryo viability

The purpose of this research was to evaluate three embryo biopsy techniques used for preimplantation genetic diagnosis (PGD) in cattle and to recommend the least invasive one for current use, especially when PGD is followed by embryo cryopreservation. Three hundred bovine embryos were biopsied by either one of the needle, aspiration or microblade method, and then checked for viability by freezing/thawing and transplantation to recipient cows. The number of pregnancies obtained after the transfer of biopsied frozen/thawed embryos was assessed 30 days later using ultrasounds. The results were significantly different between the three biopsy methods: the pregnancy rate was of 57% in cows that received embryos biopsied by needle, 43% in cows that received embryos biopsied by aspiration, and 31% in cows that received embryos biopsied by microblade. Choosing an adequate biopsy method is therefore of great importance in embryos that will undergo subsequent cryopreservation, as it significantly influences their viability after thawing.

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par-4, a gene required for cytoplasmic localization and determination of specific cell types in Caenorhabditis elegans embryogenesis.

Genetics ◽

10.1093/genetics/130.4.771 ◽

1992 ◽

Vol 130 (4) ◽

pp. 771-790 ◽

Cited By ~ 5

Author(s):

D G Morton ◽

J M Roos ◽

K J Kemphues

Keyword(s):

Caenorhabditis Elegans ◽

Cell Types ◽

Intestinal Cells ◽

Specific Cell ◽

Cytoplasmic Localization ◽

Loss Of Function ◽

Embryo Viability ◽

Cell Stage ◽

Maternal Genome

Abstract Specification of some cell fates in the early Caenorhabditis elegans embryo is mediated by cytoplasmic localization under control of the maternal genome. Using nine newly isolated mutations, and two existing mutations, we have analyzed the role of the maternally expressed gene par-4 in cytoplasmic localization. We recovered seven new par-4 alleles in screens for maternal effect lethal mutations that result in failure to differentiate intestinal cells. Two additional par-4 mutations were identified in noncomplementation screens using strains with a high frequency of transposon mobility. All 11 mutations cause defects early in development of embryos produced by homozygous mutant mothers. Analysis with a deficiency in the region indicates that it33 is a strong loss-of-function mutation. par-4(it33) terminal stage embryos contain many cells, but show no morphogenesis, and are lacking intestinal cells. Temperature shifts with the it57ts allele suggest that the critical period for both intestinal differentiation and embryo viability begins during oogenesis, about 1.5 hr before fertilization, and ends before the four-cell stage. We propose that the primary function of the par-4 gene is to act as part of a maternally encoded system for cytoplasmic localization in the first cell cycle, with par-4 playing a particularly important role in the determination of intestine. Analysis of a par-4; par-2 double mutant suggests that par-4 and par-2 gene products interact in this system.

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A Novel Infection Protocol in Zebrafish Embryo to Assess Pseudomonas aeruginosa Virulence and Validate Efficacy of a Quorum Sensing Inhibitor In Vivo

Pathogens ◽

10.3390/pathogens10040401 ◽

2021 ◽

Vol 10 (4) ◽

pp. 401

Author(s):

Pauline Nogaret ◽

Fatima El El Garah ◽

Anne-Béatrice Blanc-Potard

Keyword(s):

Pseudomonas Aeruginosa ◽

Animal Model ◽

Quorum Sensing ◽

Drug Testing ◽

Drug Efficacy ◽

Embryo Viability ◽

Immersion Method ◽

Opportunistic Human Pathogen

The opportunistic human pathogen Pseudomonas aeruginosa is responsible for a variety of acute infections and is a major cause of mortality in chronically infected cystic fibrosis patients. Due to increased resistance to antibiotics, new therapeutic strategies against P. aeruginosa are urgently needed. In this context, we aimed to develop a simple vertebrate animal model to rapidly assess in vivo drug efficacy against P. aeruginosa. Zebrafish are increasingly considered for modeling human infections caused by bacterial pathogens, which are commonly microinjected in embryos. In the present study, we established a novel protocol for zebrafish infection by P. aeruginosa based on bath immersion in 96-well plates of tail-injured embryos. The immersion method, followed by a 48-hour survey of embryo viability, was first validated to assess the virulence of P. aeruginosa wild-type PAO1 and a known attenuated mutant. We then validated its relevance for antipseudomonal drug testing by first using a clinically used antibiotic, ciprofloxacin. Secondly, we used a novel quorum sensing (QS) inhibitory molecule, N-(2-pyrimidyl)butanamide (C11), the activity of which had been validated in vitro but not previously tested in any animal model. A significant protective effect of C11 was observed on infected embryos, supporting the ability of C11 to attenuate in vivo P. aeruginosa pathogenicity. In conclusion, we present here a new and reliable method to compare the virulence of P. aeruginosa strains in vivo and to rapidly assess the efficacy of clinically relevant drugs against P. aeruginosa, including new antivirulence compounds.

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The Role of Polymeric Coatings for a Safe-by-Design Development of Biomedical Gold Nanoparticles Assessed in Zebrafish Embryo

Nanomaterials ◽

10.3390/nano11041004 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1004

Author(s):

Pamela Floris ◽

Stefania Garbujo ◽

Gabriele Rolla ◽

Marco Giustra ◽

Lucia Salvioni ◽

...

Keyword(s):

Gold Nanoparticles ◽

Significant Inhibition ◽

Zebrafish Embryos ◽

Design Development ◽

Embryo Viability ◽

Fish Embryo ◽

Toxic Response ◽

Consequent Reduction ◽

Vertebrate Model ◽

Safe By Design

In the biomedical field, gold nanoparticles (GNPs) have attracted the attention of the scientific community thanks to their high potential in both diagnostic and therapeutic applications. The extensive use of GNPs led researchers to investigate their toxicity, identifying stability, size, shape, and surface charge as key properties determining their impact on biological systems, with possible strategies defined to reduce it according to a Safe-by-Design (SbD) approach. The purpose of the present work was to analyze the toxicity of GNPs of various sizes and with different coating polymers on the developing vertebrate model, zebrafish. In particular, increasing concentrations (from 0.001 to 1 nM) of 6 or 15 nm poly-(isobutylene-alt-maleic anhydride)-graft-dodecyl polymer (PMA)- or polyethylene glycol (PEG)-coated GNPs were tested on zebrafish embryos using the fish embryo test (FET). While GNP@PMA did not exert significant toxicity on zebrafish embryos, GNP@PEG induced a significant inhibition of embryo viability, a delay of hatching (with the smaller size NPs), and a higher incidence of malformations, in terms of tail morphology and eye development. Transmission electron microscope analysis evidenced that the more negatively charged GNP@PMA was sequestered by the positive charges of chorion proteins, with a consequent reduction in the amount of NPs able to reach the developing embryo and exert toxicological activity. The mild toxic response observed on embryos directly exposed to GNP@PMA suggest that these NPs are promising in terms of SbD development of gold-based biomedical nanodevices. On the other hand, the almost neutral GNP@PEG, which did not interact with the chorion surface and was free to cross chorion pores, significantly impacted the developing zebrafish. The present study raises concerns about the safety of PEGylated gold nanoparticles and contributes to the debated issue of the free use of this nanotool in medicine and nano-biotechnologies.

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Effects of Vitrification on the Blastocyst Gene Expression Profile in a Porcine Model

International Journal of Molecular Sciences ◽

10.3390/ijms22031222 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1222

Author(s):

Cristina Cuello ◽

Cristina A. Martinez ◽

Josep M. Cambra ◽

Inmaculada Parrilla ◽

Heriberto Rodriguez-Martinez ◽

...

Keyword(s):

Gene Expression ◽

Gene Expression Analysis ◽

Survival Rates ◽

Control Group ◽

P Value ◽

Transcriptome Profile ◽

Embryo Viability ◽

The Impact

This study was designed to investigate the impact of vitrification on the transcriptome profile of blastocysts using a porcine (Sus scrofa) model and a microarray approach. Blastocysts were collected from weaned sows (n = 13). A total of 60 blastocysts were vitrified (treatment group). After warming, vitrified embryos were cultured in vitro for 24 h. Non-vitrified blastocysts (n = 40) were used as controls. After the in vitro culture period, the embryo viability was morphologically assessed. A total of 30 viable embryos per group (three pools of 10 from 4 different donors each) were subjected to gene expression analysis. A fold change cut-off of ±1.5 and a restrictive threshold at p-value < 0.05 were used to distinguish differentially expressed genes (DEGs). The survival rates of vitrified/warmed blastocysts were similar to those of the control (nearly 100%, n.s.). A total of 205 (112 upregulated and 93 downregulated) were identified in the vitrified blastocysts compared to the control group. The vitrification/warming impact was moderate, and it was mainly related to the pathways of cell cycle, cellular senescence, gap junction, and signaling for TFGβ, p53, Fox, and MAPK. In conclusion, vitrification modified the transcriptome of in vivo-derived porcine blastocysts, resulting in minor gene expression changes.

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Temperature control of male embryo viability of the aphidMegoura viciae

Invertebrate Reproduction & Development ◽

10.1080/07924259.1993.9672313 ◽

1993 ◽

Vol 23 (2-3) ◽

pp. 183-187

Author(s):

ROBERTO CREMA ◽

D. C. GAUTAM

Keyword(s):

Temperature Control ◽

Embryo Viability ◽

Male Embryo

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Disruption of Ini1 Leads to Peri-Implantation Lethality and Tumorigenesis in Mice

Molecular and Cellular Biology ◽

10.1128/mcb.21.10.3598-3603.2001 ◽

2001 ◽

Vol 21 (10) ◽

pp. 3598-3603 ◽

Cited By ~ 213

Author(s):

Cynthia J. Guidi ◽

Arthur T. Sands ◽

Brian P. Zambrowicz ◽

Tod K. Turner ◽

Delia A. Demers ◽

...

Keyword(s):

Tumor Suppressor ◽

Germ Line ◽

Inner Cell Mass ◽

Cell Mass ◽

Tumor Formation ◽

Embryo Viability ◽

Early Embryonic Lethality ◽

Poorly Differentiated ◽

Rhabdoid Tumors

ABSTRACT SNF5/INI1 is a component of the ATP-dependent chromatin remodeling enzyme family SWI/SNF. Germ line mutations ofINI1 have been identified in children with brain and renal rhabdoid tumors, indicating that INI1 is a tumor suppressor. Here we report that disruption of Ini1 expression in mice results in early embryonic lethality. Ini1-null embryos die between 3.5 and 5.5 days postcoitum, and Ini1-null blastocysts fail to hatch, form the trophectoderm, or expand the inner cell mass when cultured in vitro. Furthermore, we report that approximately 15% ofIni1-heterozygous mice present with tumors, mostly undifferentiated or poorly differentiated sarcomas. Tumor formation is associated with a loss of heterozygocity at the Ini1 locus, characterizing Ini1 as a tumor suppressor in mice. Thus, Ini1 is essential for embryo viability and for repression of oncogenesis in the adult organism.

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