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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 721 records · Page 40
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Design, synthesis and anticancer activities of halogenated Phenstatin analogs as microtubule destabilizing agent

A series of halogenated Phenstatin analogs were designed as microtubule destabilizing agent by docking study. It was synthesized within three steps starting from 2-chloro-5-iodobenzoic acid and substituted benzene. All the products were characterized by {sup 1}H NMR and {sup 13}C NMR spectral analysis, and the stereochemical structure was also confirmed by a single crystal X-ray diffraction crystallographic analysis. The microtubule destabilizing activities were evaluated in vitro with human liver cancer Huh-7 cell line and human lung cancer A549 cell line. Some of the HPAs were achieved IC{sub 50} about 5.0 μM against human liver cancer Huh-7 cells. .

60 APPLIED LIFE SCIENCES↗
DOE OSTI2019

Discovery of 3-(thiophen/thiazole-2-ylthio)pyridine derivatives as multitarget anticancer agents

A series of novel 3-(thiophen/thiazole-2-ylthio)pyridine derivatives were designed and synthesized as IGF-1R tyrosine kinase inhibitors. All the target compounds were tested for their IGF-1R kinase inhibitory activities and cytotoxicities against five cancer cell lines (K562, Hep-G2, HCT-116, WSU-DLCL2, and A549). Although all these compounds exhibited moderate to potent cancer cell proliferation inhibitory activities (the most potent compound 43 showed IC{sub 50} value of 1.3 ± 0.9 μM against WSU-DLCL2 cell line), IGF-1R inhibition were not observed. In order to identify the exact target of these analogues, selected compounds were further screened for various kinases. The results indicated that this series of compounds may exert their anticancer activities through inhibiting various kinases including FGFR 3, EGFR, JAK, and RON. In addition, cell cycle analysis of compound 43 on Hep-G2 cells showed cell cycle arrest at G1/G0 phase. All the experiments validated the potential of 3-(thiophen/thiazole-2-ylthio)pyridine analogues as multi-target anticancer agents.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2019

New histone deacetylase inhibitors and anticancer agents from Curcuma longa

The aims of this study were to explore histone deacetylase inhibitory and antioxidant activities of curcuminoids as well as derivatives of curcumin. Curcumin (6), demethoxycurcumin (7), dihydrocurcumin (8), bisdemethoxycurcumin (9), and hydroxycurcumin (10) were isolated and tested against histone deacetylases in HeLa nuclear extract. Hydroxycurcumin (10) showed the best inhibition among the isolated compounds. Some curcumin derivatives were also prepared and tested. The potential derivatives were tested on five cancer cell lines. All compounds exhibited slightly weaker antiproliferative activities against cancer cells and less toxic to non-cancer cells than curcumin (6). The least toxic derivative (17) exhibited the best antiproliferative activity against human cervical cancer cell lines (HeLa) with the IC{sub 50} value of 4.69 ± 0.14 μM. The most active histone deacetylase inhibitor (19) showed the highest potency against human colon cancer cell lines (HCT116) and the selective binding to HDAC4 based on molecular docking experiments. Most derivatives possessed antioxidant activities superior to curcumin. The results suggested potential candidates for anticancer agents.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2020

Discovery of treatment for nerve agents targeting a new metabolic pathway

The inhibition of acetylcholinesterase is regarded as the primary toxic mechanism of action for chemical warfare agents. Recently, there have been numerous reports suggesting that metabolic processes could significantly contribute to toxicity. As such, we applied a multi-omics pipeline to generate a detailed cascade of molecular events temporally occurring in guinea pigs exposed to VX. Proteomic and metabolomic profiling resulted in the identification of several enzymes and metabolic precursors involved in glycolysis and the TCA cycle. All lines of experimental evidence indicated that there was a blockade of the TCA cycle at isocitrate dehydrogenase 2, which converts isocitrate to α-ketoglutarate. Using a primary beating cardiomyocyte cell model, we were able to determine that the supplementation of α-ketoglutarate subsequently rescued cells from the acute effects of VX poisoning. This study highlights the broad impacts that VX has and how understanding these mechanisms could result in new therapeutics such as α-ketoglutarate.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2019

Comparison of two small bowel distending agents for enterography in pediatric small bowel imaging

Objective: To evaluate the ability of pediatric patients with known or suspected inflammatory bowel disease to ingest a new oral distending agent at CT or MR enterography (CTE/MRE), and to determine the impact on small bowel (SB) distension and diagnostic confidence. Materials and methods: The study design is that of retrospective review of pediatric patients who underwent CTE or MRE from January 2014 to June 2016. Patients ingested low-concentration barium suspension or flavored beverage containing sorbitol and mannitol. The need for nasogastric tube (NGT) administration, amount ingested, emesis, distal extent of contrast, SB distension, terminal ileum (TI) transverse dimension, and diagnostic confidence in TI disease were assessed. Three radiologists each blindly reviewed a subset of the studies. Results: Of the total 591 scans in 504 patients, 316 scans used low-concentration barium suspension and 275 scans flavored beverage. Nearly all consumed the entire amount (97% vs. 96%). Low-concentration barium suspension exams required NGT more often (7% [23/316] vs. 1% [3/275]; p < 0.0003), and tended to have more emesis (3% [9/316] vs. 1% [3/275]; p = 0.13). Diagnostic confidence score was nearly identical (p = 0.94). Qualitative and quantitative analyses showed no difference in SB distension, except for distension of mid-ileum (flavored beverage > low-concentration barium suspension; p = 0.02). Flavored beverage exams demonstrated a slight increase in distal extent of luminal distension (p = 0.02). Conclusions: A new flavored beverage distends small bowel as well as low-concentration barium suspension, with decreased requirement for NGT insertion and improved distal extent of luminal distension, and without any decrease in diagnostic confidence in the presence or the absence of TI disease.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Diuretic Agent and Normal Saline Infusion Technique for Ultrasound-Guided Percutaneous Nephrostomies in Nondilated Pelvicaliceal Systems

Percutaneous nephrostomy (PCN) in a nondilated pelvicaliceal system is technically challenging. We describe an effective method to achieve transient dilatation of the pelvicaliceal system via induction of diuresis using infusion of a diuretic agent in normal saline, therefore allowing easier access to the pelvicaliceal system. Under real-time ultrasound guidance, the technique had been tested in 22 nephrostomies with nondilated system (a total of 20 patients with 2 patients having bilateral nephrostomies) during a 5-year period. Patients were given 40 mg of furosemide in 250 ml of normal saline solution intravenously by rapid infusion. As soon as maximum calyceal dilatation of more than 5 mm was observed, which is usually 15 min later after the end of rapid infusion, patients were positioned obliquely, and PCN procedure under ultrasound guidance was performed. The procedure was successful in 19 of the nephrostomies in 17 patients with a success rate of 86.36 % per procedure and 85 % per patient in nondilated pelvicaliceal systems. No major nephrostomy-, drug-, or technique-related complications were encountered. The technique failed to work in three patients due to the presence of double J catheters and preexisting calyceal perforation which avoided transient dilation of the pelvicaliceal system with diuresis. Diuretic infusion in saline is a feasible and effective method for PCN in nondilated pelvicaliceal systems.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Warming Effect on Miriplatin–Lipiodol Suspension as a Chemotherapeutic Agent for Transarterial Chemoembolization for Hepatocellular Carcinoma: Preliminary Clinical Experience

Purpose: To retrospectively elucidate the preliminary clinical impact of warmed miriplatin–lipiodol suspension (MPT-LPD) when used as a chemotherapeutic agent for transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). Materials and Methods: Between June and December 2010, TACE was performed with MPT-LPD at room temperature (RT group), and after January 2011, TACE with MPT-LPD warmed to 40 °C was performed (W group). The intraarterial appearance of MPT-LPD immediately after injection through microcatheters at the second-order branches was compared between the two groups with a 5-point grading system. Local therapeutic effects of HCCs as assessed by follow-up computed tomography (CT) obtained 1–3 months after TACE were compared between the groups with a 4-point grading system (TE1–TE4). After April 2011, angiography-assisted CT was routinely performed at TACE, and HCCs that revealed apparent corona enhancement (CE) were retrospectively selected. The degree of concordance between CE and MPT-LPD accumulation as assessed by CT immediately after TACE was assessed with a 3-point grading scale. Results: MPT-LPD therapy resulted in a smooth and continuous appearance in the W group (grades 1, 2, 3, 4, and 5 were, respectively, 1, 2, 11, 18, and 4) compared to the RT group (4, 0, 1, 2, and 0). The W group (TE1, TE2, TE3, and TE4 were 1, 9, 11, and 12) revealed better local therapeutic effects than the RT group (6, 3, 9, and 0) (p < 0.05). CE was found in 26 HCC nodules, and concordance between CE and MPT-LPD accumulation was observed in 66 % (grades 1, 2, and 3 were, respectively, 2, 8, and 19). Conclusion: Warmed MPT-LPD flowed more smoothly within vascular lumen, passed through tumor sinusoid of HCC, and had better local therapeutic effects at short-term observation than MPT-LPD at room temperature.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2020

Cell fusing agent virus (Flavivirus) infection in Aedes aegypti in Texas: seasonality, comparison by trap type, and individual viral loads

Abstract South Texas has experienced local transmission of Zika virus and of other mosquito-borne viruses such as chikungunya virus and dengue virus in the last decades. Using a mosquito surveillance program in the Lower Rio Grande Valley (LRGV) and San Antonio, TX, from 2016 to 2018, we detected the presence of an insect-specific virus, cell fusing agent virus (CFAV), in the Aedes aegypti mosquito population. We tested 6,326 females and 1,249 males from the LRGV and 659 females from San Antonio for CFAV by RT-PCR using specific primers. Infection rates varied from 0 to 261 per 1,000 mosquitoes in the LRGV and 115 to 208 per 1,000 in San Antonio depending on the month of collection. Infection rates per 1,000 individuals appeared higher in females collected from BG Sentinel 2 traps compared to Autocidal Gravid Ovitraps, but the ratio of the percentage of infected pools did not differ by trap type. The natural viral load in individual males ranged from 1.25 x 10 2 to 5.50 x 10 6 RNA copies and in unfed females from 5.42 x 10 3 to 8.70 x 10 6 RNA copies. Gravid females were found to harbor fewer viral particles than males and unfed females.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2019

Neuroprotective Role of Selected Antioxidant Agents in Preventing Cisplatin-Induced Damage of Human Neurons In Vitro

Chemotherapy-induced peripheral neuropathy (CIPN) is a side effect of platinum-based chemotherapy and decreases the quality of life of cancer patients. We compared neuroprotective properties of several agents using an in vitro model of terminally differentiated human cells NT2-N derived from cell line NT2/D1. Sodium azide and an active metabolite of amifostine (WR1065) increase cell viability in simultaneous treatment with cisplatin. In addition, WR1065 protects the non-dividing neurons by decreasing cisplatin caused oxidative stress and apoptosis. Accumulation of Pt in cisplatin-treated cells was heterogeneous, but the frequency and concentration of Pt in cells were lowered in the presence of WR1065 as shown by X-ray fluorescence microscopy (XFM). Transition metals accumulation accompanied Pt increase in cells; this effect was equally diminished in the presence of WR1065. To analyze possible chemical modulation of Pt-DNA bonds, we examined the platinum L III near edge spectrum by X-ray absorption spectroscopy. The spectrum found in cisplatin-DNA samples is altered differently by the addition of either WR1065 or sodium azide. Importantly, a similar change in Pt edge spectra was noted in cells treated with cisplatin and WR1065. Therefore, amifostine should be reconsidered as a candidate for treatments that reduce or prevent CIPN.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2018

Exploration of the Effect of Chitosan and Crosslinking Agent Concentration on the Properties of Dual Responsive Chitosan-g-Poly (N-Isopropylacrylamide) Co-polymeric Particles

The objective of the present study was to synthesize and evaluate the effect of change in concentration of chitosan (CS) and N,N-methylenebisacrylamide (MBA)- a cross linking agent, on various properties such as lower critical solution temperature (LCST), zeta potential, particle size and poly dispersity index (PDI) of the synthesized co-polymer. Nine different formulations of chitosan-g-poly (N-isopropylacrylamide) (CS-g-PNIPAAm) co-polymer with varying CS and MBA concentrations were synthesized by a surfactant free dispersion copolymerization method. The synthesized co-polymer was further characterized and confirmed for its structure, morphology, particle size, zeta-potential, thermo and pH responsive properties, in-vitro cyto-compatability and stability studies using various analytical tools. The data confirms the successful synthesis of co-polymer. The increase in the concentrations of CS and MBA during the polymerization of co-polymer, resulted in proportional increase of LCST and zeta potential with decrease in particle size of co-polymeric nanoparticles. pH responsive studies showed that as the pH of the medium increases particle size and zeta potential decreases with increase in LCST of co-polymeric nanoparticles. From the results, it can be inferred that the synthesized co-polymeric nanoparticles exerted thermo and pH responsive properties with biocompatibility. By varying the CS and MBA concentrations in the co-polymer, desired LCST, particle size and zeta potential for co-polymeric nanoparticles can be obtained and thus the synthesized co-polymer may have great potential to be used as a drug carrier (nanoform) with both thermo and pH responsiveness.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Citric Acid and Vitamin C as Coupling Agents for the Surface Coating of ZrO{sub 2} Nanoparticles and Their Behavior on the Optical, Mechanical, and Thermal Properties of Poly(vinyl alcohol) Nanocomposite Films

A series of bio-nanocomposites (BNC)s were fabricated through solution casting method. At first, the surfaces of ZrO{sub 2} NPs were functionalized with citric acid and Vitamin C as green modifier agents. Then, PVA as polymer matrix was embedded with different contents (4, 8 and 12 wt%) of modified ZrO{sub 2} (m-ZrO{sub 2}) NPs with the aim of ultrasonic irradiation process. The resulting BNCs were studied by various techniques. Thermal stability of obtained BNCs was enhanced after NPs’ addition to the PVA matrix. Optical activity of these new BNCs makes them potential candidate for UV shielding material. Lastly, the tensile strengths of the BNCs were increased in comparison to the pure PVA.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Synergistic Effects of Nano-zinc Oxide on Improving the Flame Retardancy of EVA Composites with an Efficient Triazine-Based Charring Agent

The synergistic effect of nano-zinc oxide (nano-ZnO) on the flame retardancy and thermal stability of intumescent flame retardant ethylene–vinyl acetate (EVA/IFR) consisting of novel hyperbranched triazine-based charring agent (HTCFA) and APP was evaluated by limiting oxygen index (LOI), UL-94 measurement, cone calorimeter test (CCT) and thermogravimetric analysis (TGA), and the residue analysis was also carried out through scanning electron microscopy (SEM), fourier transform infrared (FTIR), laser raman spectroscopy (LRS), and X-ray photoelectron spectroscopy (XPS). The results showed that introducing a certain amount of nano-ZnO could obviously enhance LOI value and UL-94 rating, and effectively restrain the combustion performance of EVA/IFR composites, leading to the decrease of heat and smoke release. The addition of 0.5 wt% nano-ZnO into EVA/IFR composite obtained the highest catalytic effectivity (CAT-EFF). TGA results uncovered a distinct synergistic carbonization effect existed between nano-ZnO and IFR, and nano-ZnO could obviously improve the high-temperature thermal stability and promote the char formation of IFR and EVA/IFR. Analysis of final char residues proved that the incorporation of appropriate amount of nano-ZnO contributed to remaining more P and forming more high-quality graphitization char layers with richer P–O–C and P–N cross-linking structures in condensed phase owing to the catalytic carbonization effect of nano-ZnO on IFR system, which played a critical role in remarkable improvement of flame retardancy and smoke suppression properties of composites.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2019

N-Silylated Benzothiazolium Dye as a Coupling Agent for Polylactic Acid/Date Palm Fiber Bio-composites

This work proposes a benzothiazole derivative bearing a silane moiety as a new coupling agent for polylactic acid (PLA) reinforced by date palm fibers (DPFs). The bio-composites are prepared by solution blending followed by melt compounding. From the samples produced, a complete characterization is performed including morphological, mechanical and thermal properties as a function of fiber content. The results show that the proposed fiber treatment is an easy and effective method to improve the interfacial properties and fiber dispersion leading to better material performance. For example, the addition of only 1 wt% of the dye–IPTMS to the bleached DPF not only improved the thermal stability of the biocomposites, but also led to a significant increase of the Young’s modulus at 7 wt% and higher torsion modulus up to 5 wt% (optimum value).

36 MATERIALS SCIENCE↗
DOE OSTI2017

Synthesis of new N-(pyridin-3-ylmethyl)-2-aminothiazoline derivatives possessing anticholinesterase and antiradical activity as potential multifunctional agents for the treatment of neurodegenerative diseases

New N-(pyridin-3-ylmethyl)-2-aminothiazolines containing various substituents at the 5 position of the thiazoline ring and the 4-tert-butylbenzyl, 4-isopropylbenzyl, or 4-fluorobenzyl moiety at the nitrogen atom of the amino group were synthesized. The inhibitory activity of the synthesized compounds against human erythrocyte acetylcholinesterase (AChE, EC 3.1.1.7), equine serum butyrylcholinesterase (BChE, EC 3.1.1.8), and porcine liver carboxylesterase (CaE, EC 3.1.1.1) was evaluated and their antioxidant properties were studied by ABTS assay. N-(Pyridin-3-ylmethyl)-2-aminothiazolines proveded to be very weak AChE inhibitors, while their inhibitory activity against BChE and CaE was structure-dependent. 2-Aminothiazolines containing the 4-tert-butylbenzyl moiety are more efficient BChE inhibitors compared to the derivatives containing the 4-isopropylbenzyl or 4-fluorobenzyl substituent. An analysis of the dependence of the esterase profile of N-(pyridin-3-ylmethyl)-2-aminothiazolines on the structure of the substituent at the 5 position of the thiazoline ring of these compounds demonstrated that the derivatives containing the iodomethyl substituent possess the highest anti-BChE activity, the compounds with R{sup 2} = H and R{sup 3} = CH{sub 2}I have the optimal esterase profile. Regardless of the structure of the substituents in the benzyl moiety, all N-(pyridin-3-ylmethyl)-2-aminothiazolines containing the iodomethyl substituent at the 5 position of the thiazoline ring exhibited high radical scavenging activity comparable with that of the standard antioxidant Trolox. N-(Pyridin-3-ylmethyl)-2-aminothiazolines were shown to be a new promising class of compounds for the design of multifunctional agents for the treatment of neurodegenerative diseases.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Reaction of N-alkyl-N′-(trimethylsilyl)carbodiimides with nitrating agents. The synthesis of N-(tert-butyl)-N′-nitrocarbodiimide

Reaction of N-Alk-N′-(trimethylsilyl)carbodiimides (Alk = Me, Bu{sup t}) with nitrating agents (N{sub 2}O{sub 5}, (NO{sub 2}){sub 2}SiF{sub 6}) affords alkyl(nitro)cyanamides and N-alkyl-N′-nitrocarbodiimides. The product ratio depends on the reaction conditions. N-(tert-butyl)-N′-nitrocarbodiimide can be obtained in almost pure form. This compound is stable at temperatures below 10 °C. Its structure was confirmed by {sup 1}Н, {sup 13}C, and {sup 14}N NMR. The reaction of N-(tert-butyl)-N′-nitrocarbodiimide with amines provides a new route to N-alkyl(aryl)-substituted N′-(tert-butyl)-N″-nitroguanidines.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Agent-Based Socio-Hydrological Hybrid Modeling for Water Resource Management

Hybrid socio-hydrological modeling has become indispensable for managing water resources in an increasingly unstable ecology caused by human activity. Most work on the subject has been focused on either qualitative socio-political recommendations with an unbounded list of vague factors or complex sociological and hydrological models with many assumptions and specialized usability. Here in this paper, we propose a simple agent-based socio-hydrological decision modeling framework for coupling dynamics associated with social behavior and groundwater contamination. The study shows that using social health risk, instead of contaminant concentration, as an optimization variable improves water management decisions aimed at maximizing social wellbeing. The social models and computational framework are designed with enough flexibility and simplicity to encourage extensions to more general socio-hydrological dynamics without compromising either computability or complexity for better data-/model-driven environmental management.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Use of Industrial Waste (Al-Dross, Red Mud, Mill Scale) as Fluxing Agents in the Sulfurization of Fe-Ni-Cu-Co Alloy by Carbothermic Reduction of Calcium Sulfate

The use of industrial waste [mill scale (MS), red mud (RM), Al-dross (AD)] as fluxing agents in the sulfurization of Fe-Ni-Cu-Co alloy to matte (Fe-Ni-Cu-Co-S) by carbothermic reduction of CaSO{sub 4} was investigated at 1673 K (1400 °C). The sulfurization efficiency (SE) was 76 (± 2) pct at RM or AD single fluxing. However, SE drastically increased to approximately 89 pct at a ‘5AD + 5MS’ combination, which was equivalent to reagent-grade chemical ‘5Al{sub 2}O{sub 3} + 5Fe{sub 2}O{sub 3}’ fluxing (SE = 88 pct). The present results can be used to improve the cost-effective recovery of rare metals (Ni and Co) from deep sea manganese nodules.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Gas Release Behavior of Cu-TiH{sub 2} Composite Powder and Its Application as a Blowing Agent to Fabricate Aluminum Foams with Low Porosity and Small Pore Size

Compared to traditional pore structure with high porosity (≥ 80 pct) and large pore size (≥ 3 mm), aluminum foams with low porosity (60 to 70 pct) and small pore size (≤ 2 mm) possess higher compressive property and formability. In order to achieve the goal of reducing pore size, Cu-TiH{sub 2} composite powder prepared by ball milling preoxidized TiH{sub 2} with Cu powder was used as a blowing agent. Its gas release behavior was characterized by thermogravimetric analysis and differential scanning calorimetry. The results show that the ball milling treatment can advance the gas release process and slow the gas release rate at the same time. All these changes are favorable to the reduction of porosity and pore size. Such Cu-TiH{sub 2} composite powder provides an alternative way to fabricate aluminum foams with low porosity and small pore size.

36 MATERIALS SCIENCE↗