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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

The Removal of Acid Violet 90 from Aqueous Solutions Using PANI and PANI/Clinoptilolite Composites: Isotherm and Kinetics

Polyaniline (PANI) and polyaniline/Gördes-clinoptilolite (PANI/GC) composite materials were synthesized by the chemical oxidative polymerization technique and used in the adsorption of Acid Violet 90 metal-complex dye (AV 90). The samples were characterized by X-ray diffractions, nitrogen adsorption–desorption isotherms, scanning electron microscopes and Fourier transform infrared. The effect of initial pH (2–8), sorbent dosage (0.5–4.0 g/L) and initial dye concentrations (50–400 mg/L) on adsorption onto PANI and PANI/GC were examined in a batch system. Langmuir, Freundlich and Temkin isotherm models were used to investigate the adsorption mechanism of AV 90 on PANI and PANI/GC. Langmuir isotherm model for PANI/GC and Freundlich isotherm model for PANI were fitted well with the experimental data. The highest dye uptake capacities were obtained with Langmuir isotherm model as 153.85 mg/g and 72.46 mg/g for PANI and PANI/GC, respectively. In order to determine the adsorption kinetics, pseudo first-order and second-order kinetic models were studied. As a result, the adsorption of AV 90 dye on PANI and PANI/GC was better identified with Pseudo second-order kinetic model than the first one.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2019

Preparation and Dewatering Property of Two Sludge Conditioners Chitosan/AM/AA and Chitosan/AM/AA/DMDAAC

Two new chitosan-grafting copolymers (chitosan-g-PAM-AA and C-chitosan-g-PAM-AA) as sludge conditioners (flocculation and aggregation) have been prepared by employing ceric sulfate as a free radical initiator under nitrogen atmosphere in aqueous solution. The optimum condition for synthesizing chitosan-grafting copolymer was determined by orthogonal experiments. The structure, morphology and property of the obtained graft polymers were characterized by FT-IR, XRD, SEM, TGA and contact angle. Further, the municipal activated sludge dewatering performance of the synthesized copolymers was evaluated by the filter cake moisture content. Herein, the effects of pH value and dewatering temperatures of activated sludge, loading dosage or cationic degree of C-chitosan-g-PAM-AA on the filter cake moisture content were investigated. The synthesized amphoteric flocculant C-chitosan-g-PAM-AA showed a highly effective flocculation capability for activated sludge compared with chitosan-g-PAM-AA, chitosan, polyacrylamide (PAM). Also, the lowest filter cake moisture content was up to 61.41%.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2019

An Eco-friendly Porous Poly(imide-ether)s for the Efficient Removal of Methylene Blue: Adsorption Kinetics, Isotherm, Thermodynamics and Reuse Performances

Poly(imide-ether)s (PIEs), which is porous in nature, was synthesized using aromatic diamines and dianhydrides via the solution polycondenzation reaction. In the process, PIEs was used as an adsorbent for the removal of basic dye [Methylene blue (MB)] from the aqueous solution. The structure and the thermal stability of PIEs were characterized by FT-IR, {sup 1}H-NMR, XRD and TG analysis, and the adsorption behaviour of the PIEs was confirmed using UV/Visible, FT-IR and SEM with EDX analysis. Batch adsorption experiments were carried out and their parameters (pH 6.95), initial MB concentration (200 mg/L), adsorbent dosage (50 mg), contact time (120 min) and temperature (28 °C) were optimized. The batch adsorption experimental data of the effect of contact time, initial MB concentration and temperature were evaluated using the adsorption kinetics (Pseudo-first order, Pseudo-second order, Elovich and Intra-particle diffusion kinetic), isotherm (Langmuir, Freundlich, Redlich–Peterson and Sips isotherms) and thermodynamic models respectively. In the study, adsorption of MB onto PIEs followed Pseudo-second kinetics and found to be the best fitting model based on the obtained experimental data. The homogeneity and heterogeneity surface nature of PIEs were elucidated with two and three isotherm parameters respectively. The adsorption thermodynamic study indicates that the adsorption of MB onto PIEs was endothermic and spontaneous in nature. The adsorbed PIEs solid waste was utilized to prepare the polymer composite, and its property was characterized. Graphical Abstract: .

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

Equilibrium, Kinetic and Thermodynamic Studies on Methylene Blue Adsorption by Konjac Glucomannan/Activated Carbon Aerogel

Activated carbon (AC) is a common adsorbent used for the purification of aqueous solutions, yet its poor aqueous dispersion may negatively affects its practicability significantly. In the present study, the fabrication of an AC aerogel immobilized with konjac glucomannan (KGM/AC) for environmental protection was reported, and the parameters (e.g. AC content in aerogel, solution pH, adsorption duration, adsorption temperature and adsorbent dosage) were analyzed systematically using methylene blue (MB) as a model adsorbate. Further, to explore the adsorption equilibrium isotherm at equilibrium, the adsorption data were respectively fitted to Langmuir and Freundlich models, while kinetics study was conducted to explain the adsorption mechanism and predict the adsorption efficiency. Besides, the effect of temperature on the adsorption behavior was assessed using Van’t Hoff equation. According to the experimental and calculative results, the adsorption data at equilibrium could be well geared into the Langmuir model, and the adsorption kinetics behavior was better consistent with the pseudo-second-order expression as well as the intra-particle diffusion model. The Brunauer, Emmett and Teller surface area of KGM/AC aerogel was 352.44 m{sup 2}/g. KGM/AC aerogel exhibited the maximal capacity of adsorption of 416.67 mg/g at 323 K, and its adsorption behavior toward MB was endothermic and spontaneous in nature.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Amino-Acid-Modified-Cashew Gum Flocculant: Synthesis, Characterization, and Application

Amphoteric poly(O-methacryloyl-L-serine)-grafted cashew gum (CG-g-P(SerMA)) flocculant was obtained with highly efficient in separation and sequential recovery of kaolin particles from aqueous suspension. The highest flocculation efficiency was achieved with a flocculant synthesized using an O-methacryloyl-L-serine:cashew gum molar ratio of 3:1. The CG-g-P(SerMA) at a dosage of 3.0 mg L{sup −1} resulted in a flocculation efficiency of more than 90% within 20 min for kaolin suspension. The efficiency, in standard experiments, the flocculant CG-g-P(SerMA) was superior to cashew gum and polyacrylamide-based commercial flocculants. The flocculation mechanism involves electrostatic interactions between the negatively charged surface of the kaolin and the protonated amino groups of the flocculant under acidic conditions. These results provide new opportunities and challenges for understanding and improving the removal of impurities present in water and wastewater.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Removal of Nitrate from Water by Alginate-Derived Carbon Aerogel Modified by Protonated Cross-Linked Chitosan

In this study, a carbonaceous aerogel with superior structural properties was synthesized from sodium alginate with a specific surface area and density of about 470 m{sup 2} g{sup −1} and 0.05 g cm{sup −3}, respectively. In order to adsorb nitrate from water, the surface of the aerogel was modified by protonated cross-linked chitosan. To investigate the morphology, elemental composition, crystalline phases and surface functional groups of the adsorbent, various techniques such as field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction analysis, Fourier transform infrared spectroscopy were employed. To study the performance of this green adsorbent in nitrate removal process, the effect of nitrate initial concentration, adsorbent dosage, pH of solutions were investigated in batch mode. It was revealed that the Langmuir isotherm model could properly describe the experimental equilibrium data and the maximum adsorption capacity was evaluated to be about 18 mg g{sup −1} at neutral pH and room temperature. Besides, the kinetic data perfectly followed the pseudo-second order model. Thermodynamic analysis showed that the adsorption reaction was spontaneous, exothermic with decreased randomness at the solid–liquid interface. The macroscopic size of the adsorbent allowed its facile separation from the solution.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Cu(II) Sorption Performance of Novel Chitosan/Ter-(vinyl pivalate-maleic anhydride-N-tert-butylacrylamide) Microcapsules

In this study, first, the ter-polymerization reaction between vinyl pivalate (VP), maleic anhydride (MA), and N-tert-butylacrylamide (NTBA) was done in inert atmosphere (N{sub 2}). FT-IR and {sup 1}HNMR spectroscopy was applied to study the chemical composition of the obtained ter-polymers. MA content of the ter-polymers was determined by following the chemical titration method. Second, novel chitosan/ter-(vinyl-pivalate-maleic-anhydride-N-tert-butylacrylamide) microcapsules were synthesized. In microcapsule production, chitosan polymer served as a matrix for acrylamide ter-polymers with four different molar ratios. The microcapsules were characterized by FT-IR and SEM analyses. Cu(II) sorption efficiency of the microcapsules were tested at different pH levels, temperature, sorbent dosage, and metal ion concentration. Comparison with blank chitosan microbeads revealed that incorporation of acrylamide ter-polymers into the cross-linked chitosan matrix increased the metal sorption. Sorption capacities of the sorbents were recorded; blank chitosan microbeads: 67.03 mg g{sup −1}, and chitosan/acrylamide ter-polymer microcapsules: in range of 75.39–98.64 mg g{sup −1}. The findings demonstrated chitosan/acrylamide ter-polymer microcapsules can be utilized in sorption of Cu(II) ions in water treatment.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Trends in Light and Temperature Sensitivity Recommendations among Licensed Biotechnology Drug Products

Inherent structural and functional properties of biotechnology-derived therapeutic biologics make them susceptible to light- and temperature-induced degradation and consequently can influence their quality. Photosensitivity of therapeutic proteins continues to be examined, but the commonalities and trends of storage conditions and information about light and temperature sensitivity among currently licensed therapeutic proteins has not been previously surveyed. Using a comprehensive and relational database approach, we conducted a scientific survey of all licensed biotechnology-derived drug products with the goal of providing evidence-based information about recommended storage conditions of formulations sorted by light- and temperature-related attributes as described for each product at licensure. We report the prevalence of indications for light and temperature sensitivity in formulations categorized by their presentation type, number of doses, container type, dosage form and active molecule type. We also report the storage temperature range across formulations and diluents for reconstitution and dilution. Formulations with excipients that potentially facilitate light-induced and thermal degradation were also noted. The result of our analysis indicates that light and temperature sensitivity are prevalent across therapeutic protein formulations. However, when a formulation is reconstituted or diluted, both light and temperature sensitivity are less clear. In addition, light and temperature sensitivity are more well defined in liquid formulations than lyophilized powder formulations, and more well defined in products manufactured in autoinjectors, prefilled-syringes, and pens than products in vials. Overall, our report provides a data-driven summary of storage conditions among therapeutic protein formulations to support the development of future biologic drug products.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Sulfur Removal by Adding Iron During the Digestion Process of High-sulfur Bauxite

This paper proposes a novel approach to sulfur removal by adding iron during the digestion process. Iron can react with high-valence sulfur (S{sub 2}O{sub 3}{sup 2−}, SO{sub 3}{sup 2−}, SO{sub 4}{sup 2−}) to generate S{sup 2−} at digestion temperature, and then S{sup 2−} enter red mud in the form of Na{sub 3}FeS{sub 3} to be removed. As iron dosage increases, high-valence sulfur concentration decreases, but the concentration of S{sup 2−} increases; sulfur digestion rate decreases while sulfur content in red mud markedly increases; the alumina digestion rate, conversely, remains fairly stable. So sulfur can be removed completely by adding iron in digestion process, which provide a theoretical basis for the effective removal of sulfur in alumina production process.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Sulfidation and Sulfur Fixation of Jarosite Residues During Reduction Roasting

This study investigated the sulfidation and sulfur fixation of jarosite residues during reduction roasting in the presence of carbon. The effects of roasting temperature and carbon dosage were investigated based on thermodynamic calculation. The results indicated that more than 98 pct of zinc contained in the residue was converted into zinc sulfides, and more than 91 pct of sulfur was fixed in the roasted residue. Carbon addition promoted not only the sulfidation of zinc but also the fixation of sulfur, thereby eliminating SO{sub 2} emission. The growth of sulfide particles was strongly influenced by roasting temperature. The size of sulfide particles significantly increased when the temperature was above 1173 K (900 °C) because of the formation of a liquid phase during the roasting process. However, high temperature could increase the consumption of carbon powder.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Experimental Investigation of Mechanical Performance and Printability of Gamma-Irradiated Additively Manufactured ABS

The work presented in this paper investigates the effects of gamma radiation on ABS in forms of irradiated 3D-printed parts, and irradiated filament used to later 3D-printed parts, using a cobalt-60 gamma irradiator. Tensile and flexural test samples were fabricated using off-the-shelf FDM 3D printers and irradiated at different dosages. Mechanical properties including elastic and flexure moduli, ultimate and flexural strength, % elongation at break, and surface hardness were evaluated, and results were compared to a control group. Evidence of cross-linking and chain scission and signs of possible oxidation of polymer caused by irradiation were found in both test groups which led to changes in mechanical properties. Moreover, it was found that ABS filament retains its printability after absorbing 15 kGy of gamma radiation and that its mechanical performance is very similar to those of irradiated samples at the same dose. Obtained results show promise for using ABS to fabricate sterile surgical instruments.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2019

Interaction between phytotherapy and oral anticancer agents: prospective study and literature review

Cancer is becoming more prevalent in elderly patient. Due to polypharmacy, older adults with cancer are predisposed to drug-drug interactions. There is also an increasing interest in the use of complementary and alternative medicine (CAM). Thirty to seventy percent of patients with cancer have used CAM. Through pharmaceutical counseling sessions, we can provide advices on herb–drug interactions (HDI). All the patients seen in pharmaceutical counseling sessions were prospectively included. Information was collected during these sessions: prescribed medication (oral anticancer agents (OAA) and other drugs), CAM (phytotherapy especially), and use of over-the-counter (OTC) drugs. If pharmacist considered an interaction or an intervention clinically relevant, the oncologist was notified. Then, a literature review was realized to identify the potential HDI (no interactions, precautions for use, contraindication). Among 201 pharmacist counseling sessions, it resulted in 104 interventions related to 46 HDI, 28 drug-drug interactions and 30 others (wrong dosage, omission…). To determine HDI, we review 73 medicinal plants which are used by our patients with cancer and 31 OAA. A total of 1829 recommendations were formulated about 59 (75%) medical plants and their interaction with an OAA. Herb–drug interactions should not be ignored by healthcare providers in their management of cancer patients in daily practice.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2018

Photo-controlled release of paclitaxel and model drugs from RNA pyramids

Stimuli-responsive release of drugs from a nanocarrier in spatial-, temporal-, and dosage-controlled fashions is of great interest in the pharmaceutical industry. Paclitaxel is one of the most effective and popular chemotherapeutic drugs against a number of cancers such as metastatic or nonmetastatic breast cancer, non–small cell lung cancer, refractory ovarian cancer, AIDS-related Kaposi’s sarcoma, and head and neck cancers. Here, by taking the advantage of RNA nanotechnology in biomedical and material science, we developed a three-dimensional pyramid-shaped RNA nanocage for a photocontrolled release of cargo, using paclitaxel as a model drug. The light-triggered release of paclitaxel or fluorophore Cy5 was achieved by incorporation of photocleavable spacers into the RNA nanoparticles. Upon irradiation with ultraviolet light, cargos were rapidly released (within 5 min). In vitro treatment of breast cancer cells with the RNA nanoparticles harboring photocleavable paclitaxel showed higher cytotoxicity as compared to RNA nanoparticles without the photocleavable spacer. The methodology provides proof of concept for the application of the light-triggered controlled release of drugs from RNA nanocages.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2023

Natural transformation as a tool in Acinetobacter baylyi : Evolution by amplification of gene copy number

For many years, the natural competency of Acinetobacter baylyi ADP1 facilitated studies of bacterial metabolism, biochemistry, and physiology. With the advent of synthetic biology, new opportunities arise to exploit the remarkable transformability and chromosomal plasticity of this model organism. In this chapter, we describe a recently developed method, “Evolution by Amplification and Synthetic Biology” (EASy). EASy allows the targeted amplification of chromosomal segments that give rise to new phenotypes. Increased gene dosage regulates protein expression in a rudimentary fashion by establishing a chromosomal array in which copy number adjusts via recombination between repeated DNA sequences. Selective conditions enrich for cells within the population that confer a growth advantage. Under continuous selective pressure, beneficial mutations may accumulate in any genomic region. Such mutations favor decreases in the average copy number of the target region. Thus, the genetic flexibility afforded by transient copy number variation helps accelerate the selection of engineered strains with desired traits during laboratory evolution. As a result, thanks to the extremely simple genetic manipulation of Acinetobacter baylyi ADP1, the EASy method can be readily implemented by researchers without the need for advanced instrumentation or complex cloning techniques.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2017

Antitumor activity, pharmacokinetics, tumor-homing effect, and hepatotoxicity of a species cross-reactive c-Met antibody

Highlights: • We developed a novel human and mouse cross-reactive antibody, IRCR201. • IRCR201 inhibits HGF/c-Met pathway through c-Met degradation. • IRCR201 interferes with crosstalk between c-Met and other RTKs. • IRCR201 is highly tumor-specific and has a stable pharmacokinetic profile. • IRCR201 provides exceptional anti-tumoral activity in a GBM xenograft model. The receptor tyrosine kinase c-Met plays critical roles in promoting tumor growth, invasion, metastasis, and angiogenesis in various types of cancer and is a promising therapeutic target. The development of a species cross-reactive therapeutic antibody could provide useful to comprehensive preclinical assessment in animal models. Towards this goal, we developed human/mouse cross-reactive c-Met antibodies using an antibody phage library. IRCR201, a c-Met antibody with species cross-reactivity, successfully inhibited the HGF/c-Met signaling pathway via degradation of c-Met and disruption of the binding with its partners, and demonstrated strong in vivo antitumor activity. In pharmacokinetic analysis, IRCR201 exhibited a nonlinear pharmacokinetic profile and showed rapid serum clearance at low dosage. Ex vivo fluorescence imaging and immunohistochemistry demonstrated strong tumor accumulation of IRCR201. Hepatotoxicity analysis revealed that IRCR201 does not significantly affect primary human and mouse hepatocytes. Serum chemistry analysis demonstrated that the alanine aminotransferase serum level was elevated in mice treated with 30 mg/kg IRCR201 than in PBS-treated mice, whereas the levels of aspartate aminotransferase and blood urea nitrogen did not significantly differ. Thus, IRCR201 is a potent therapeutic antibody that can disrupt the HGF/c-Met signaling axis and its species cross-reactivity would enable to evaluate precise biological activity in animal models.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Cardiac-specific delivery by cardiac tissue-targeting peptide-expressing exosomes

Highlights: • Genetic modification of exosomes could enhance exosome delivery to heart. • CTP-Exo did not show toxic effects in vitro or in vivo. • CTP-Exo might be used as a therapeutic tool for heart disease. Naturally occurring RNA carriers such as exosomes might be an untapped source of effective delivery vehicles. However, if exosomes are to be exploited for therapeutic applications, they must target specific tissues or cell types to avoid off-target effects. This study evaluated whether genetic modification of exosomes could enhance exosome delivery to heart cells and heart tissue without toxicity. Exosomes expressing cardiac-targeting peptide (CTP)-Lamp2b on the exosomal membrane (CTP-Exo) were generated by introducing vectors encoding CTP-Lamp2b into HEK 293 cells. The expression of CTP-Lamp2b peptide on exosomes was stabilized by attaching glycosylation sequences. Exosomes expressing only Lamp2b on exosomal membranes (CTL-Exo) were generated as a control. The in vitro and in vivo uptake of CTL-Exo and CTP-Exo was evaluated in cell lines and mice. Both exosomes were delivered to HEK 293 and H9C2 cells. The delivery of the exosome was not different between CTP-Exo and CTL-Exo in HEK 293 cells, whereas the delivery of CTP-Exo was 16% greater than that of CTL-Exo in H9C2 cells (P = 0.047). Cell viability was maintained at almost 100% with different dosages of both CTL-Exo and CTP-Exo. Moreover, compared with CTL-Exo, the in vivo delivery of exosomes to the hearts of mice was increased by 15% with CTP-Exo (P = 0.035). The delivery to livers and spleens was not different between the two exosomes. Genetic modification of exosomes by expressing CTP-Lamp2b on the exosomal membrane enhanced exosome delivery to heart cells and the heart tissue. These results suggested that CTP-Exo might be used as a therapeutic tool for heart disease.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

In vivo masculinizing function of the Ostrinia furnacalis Masculinizer gene

Highlights: • We established a system for monitoring the sex of a single O. furnacalis embryo. • Of Masc is a masculinizing factor of O. furnacalis. • Masc is a masculinizing factor in an insect species distant from Bombycidae. The Masculinizer gene (Masc) encodes a CCCH tandem zinc finger protein essential for masculinization and dosage compensation in the silkworm Bombyx mori. Previously we identified a Masc orthologue from the crambid Ostrinia furnacalis (OfMasc) and observed its masculinizing activity in the B. mori cultured cell line BmN-4. However, the role of OfMasc in masculinization of O. furnacalis has not been assessed. In this study, we unexpectedly discovered that all of the male larvae that escaped from Wolbachia-induced embryonic male-killing by OfMasc cRNA injection expressed the female-type splicing variants of O. furnacalis doublesex (Ofdsx). To clarify the role of OfMasc in the masculinization process in vivo, we established a system to monitor both sex chromosome- and dsx splicing-based sexes from a single O. furnacalis embryo. Using this system, we investigated the effects of OfMasc knockdown in early embryos on Ofdsx splicing and found that depletion of OfMasc mRNA in male embryos induced the production of the female-type splicing variants of Ofdsx. This result indicates that OfMasc is required for masculinization in O. furnacalis, and that the Masc protein possesses masculinizing activity in an insect species that is phylogenetically distant from Bombycidae.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

CTP synthase knockdown during early development distorts the nascent vertebral column and causes fluid retention in multiple tissues in zebrafish

Highlights: • Morpholino-based knockdown of ctps during early development produces zebrafish embryos with curved spines and tissue oedema. • Knockdown of ctps1a, and not ctps1b, induces more severe, longer-lasting defects. • Phenotypes are exacerbated when morpholinos against both gene variants are supplied together at uneven ratios. • The same phenotypes were recovered from embryos treated with DON, a CTPS activity-inhibiting drug. CTP Synthase (CTPS) is a metabolic enzyme that is recognized as a catalyst for nucleotide, phospholipid and sialoglycoprotein production. Though the structural characteristics and regulatory mechanisms of CTPS are well-understood, little is known regarding the extent of its involvement during the early developmental stages of vertebrates. Zebrafish carries two CTPS genes, annotated as ctps1a and ctps1b. Phylogenetic analyses show that both genes had diverged from homologues in the ancestral Actinopterygii, Oreochromis niloticus. Conservation of common CTPS-catalytic regions further establishes that both proteins are likely to be functionally similar to hsaCTPS. Here, we show that ctps1a is more critical throughout the initial period of embryonic development than ctps1b. The effects of concurrent partial knockdown are dependent on ctps1a vs ctps1b dosage ratios. When these are equally attenuated, abnormal phenotypes acquired prior to the pharyngula period disappear in hatchlings (48hpf); however, if either gene is more attenuated than the other, these only become more pronounced in advanced stages. Generally, disruption to normal ctps1a or ctps1b expression levels by morpholinos culminates in the distortion of the early spinal column as well as multiple-tissue oedema. Other effects include slower growth rates, increased mortality rates and impaired structural formation of the young fish's extremities. Embryos grown in DON, a glutamine-analogue drug and CTPS antagonist, also exhibit similar characteristics, thus strengthening the validity of the morpholino-induced phenotypes observed. Together, our results demonstrate the importance of CTPS for the development of zebrafish embryos, as well as a disparity in activity and overall importance amongst isozymes.

60 APPLIED LIFE SCIENCES↗