Publications by authors named "Ly Pham"

Lyotropic liquid crystals (LLCs) are interesting wall-materials for encapsulation technology, in which monoacylglycerols (MAGs) are considered as potential ingredient for LLC formulation. This study, therefore, applied palm oil-based MAGs to encapsulate Gac fruit oils and compared the effect of two drying methods (freeze-drying and spray-drying) on the quality of products during storage. Wall-materials were prepared by ultrasound dispersing MAGs/water mixtures (40/60, w/w) into Pluronic solution (2%, w/w) to formulate LLC dispersions.

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This work estimates benchmarks for new approach method (NAM) performance in predicting organ-level effects in repeat dose studies of adult animals based on variability in replicate animal studies. Treatment-related effect values from the Toxicity Reference database (v2.1) for weight, gross, or histopathological changes in the adrenal gland, liver, kidney, spleen, stomach, and thyroid were used.

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  • Small intestinal vacuolation caused by the compound HAP-1 was seen in rats but not in dogs, despite higher drug exposure in dogs.
  • Rats consistently exhibited epithelial vacuolation at various doses, while dogs only showed temporary vacuolation at specific time points.
  • The differences in intestinal response between species were linked to how much HAP-1 and its metabolite accumulated in the intestines, with rats having significantly higher concentrations, leading to lipid metabolism issues and ER stress observed only in rats.
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Human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) are currently used following the Comprehensive in vitro Proarrhythmic Assay (CiPA) initiative and subsequent recommendations in the International Council for Harmonization (ICH) guidelines S7B and E14 Q&A, to detect drug-induced cardiotoxicity. Monocultures of hiPSC-CMs are immature compared to adult ventricular cardiomyocytes and might lack the native heterogeneous nature. We investigated whether hiPSC-CMs, treated to enhance structural maturity, are superior in detecting drug-induced changes in electrophysiology and contraction.

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Drug-induced seizure liability is a significant safety issue and the basis for attrition in drug development. Occurrence in late development results in increased costs, human risk, and delayed market availability of novel therapeutics. Therefore, there is an urgent need for biologically relevant, in vitro high-throughput screening assays (HTS) to predict potential risks for drug-induced seizure early in drug discovery.

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  • IL-23, a cytokine linked to inflammatory and autoimmune diseases like inflammatory bowel disease (IBD), impacts intestinal regulatory T cells (Tregs) but its exact role is not well understood.
  • Research reveals that Tregs in the colon have higher levels of IL-23 receptor (Il23r), but their numbers decrease when exposed to IL-23, which also hinders their ability to suppress inflammation.
  • IL-23 signaling appears to negatively affect intestinal Tregs by increasing their turnover and promoting apoptosis, suggesting it may play a role in chronic inflammation seen in IBD patients.
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Cellular metabolism influences immune cell function, with mitochondrial fatty acid β-oxidation and oxidative phosphorylation required for multiple immune cell phenotypes. Carnitine palmitoyltransferase 1a (Cpt1a) is considered the rate-limiting enzyme for mitochondrial metabolism of long-chain fatty acids, and Cpt1a deficiency is associated with infant mortality and infection risk. This study was undertaken to test the hypothesis that impairment in Cpt1a-dependent fatty acid oxidation results in increased susceptibility to infection.

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Background And Purpose: G-protein coupled receptor 17 (GPR17) is an orphan receptor involved in the process of myelination, due to its ability to inhibit the maturation of oligodendrocyte progenitor cells (OPCs) into myelinating oligodendrocytes. Despite multiple claims that the biological ligand has been identified, it remains an orphan receptor.

Experimental Approach: Seventy-seven oxysterols were screened in a cell-free [ S]GTPγS binding assay using membranes from cells expressing GPR17.

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exposure of multiple Gram-negative bacteria to an aminoglycoside (AG) antibiotic has previously been demonstrated to result in bacterial alterations that interact with host factors to suppress Gram-negative pneumonia. However, the mechanisms resulting in suppression are not known. Here, the hypothesis that Gram-negative bacteria bind and retain AGs, which are introduced into the lung and interact with host defenses to affect bacterial killing, was tested.

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  • Limited toxicity data exists for most PFAS (per- and polyfluoroalkyl substances), prompting the need for an efficient method to prioritize which compounds require further safety assessments.
  • The threshold of toxicological concern (TTC) approach, which estimates a safe exposure level based on chemical properties, was applied to a dataset of 27 PFAS to evaluate its effectiveness.
  • Results indicated that the PFAS dataset followed similar toxicity patterns as previously studied substances, suggesting the TTC approach could be a useful tool for assessing the safety of PFAS chemicals.
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A typical structure of thermal spray coatings consisted of molten particles, semi-molten particles, oxides, pores, and cracks. These factors caused the porosity of sprayed coatings, leading to a significant influence on the coating properties, especially their wear-corrosion resistance. In this study, a post-spray sealing treatment of CrC-NiCr/AlO-TiO plasma-sprayed coatings was carried out, and then, their corrosion properties were evaluated, before and after the treatment.

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Acinetobacter baumannii is a nosocomial pathogen that exhibits substantial genomic plasticity. Here, the identification of two variants of A. baumannii ATCC 17978 that differ based on the presence of a 44-kb accessory locus, named AbaAL44 (A.

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  • New approach methodologies (NAMs) for chemical hazard assessment are often compared to animal studies, but the variability in animal data can impact the accuracy of NAM predictions.
  • The US EPA's Toxicity Reference Database (ToxRefDB) helps researchers analyze the variability of effect levels, like the lowest observable adverse effect level (LOAEL), across various toxicity studies to improve understanding of chemical hazards.
  • The study used statistical models to measure the variance in these effect levels, finding that the maximum predictive accuracy for NAMs may only reach about 55-73%, meaning there's still a significant amount of uncertainty in predictions of systemic toxicity.
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This study proposes the approach of context-dependent data envelopment analysis (DEA) to measure operating performance in halfway houses to enable suitable adjustments at the current economic scale. The proposed approach can be used to discriminate the performance of efficient halfway houses and provide more accurate DEA results related to the performance of all halfway houses in a region or a country. The relative attractiveness and progress were also evaluated, and individual halfway houses' competitive advantage and potential competitors could be determined.

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Thousands of chemicals have limited, or no hazard data readily available to characterize human risk. The threshold of toxicological concern (TTC) constitutes a science-based tool for screening level risk-based prioritization of chemicals with low exposure. Herein we compare TTC values to more rigorously derived reference dose (RfD) values for 288 chemicals in the U.

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Antimicrobial resistance is increasing in pathogenic bacteria. Yet, the effect of antibiotic exposure on resistant bacteria has been underexplored and may affect pathogenesis. Here we describe the discovery that propagation of the human pathogen Acinetobacter baumannii in an aminoglycoside antibiotic results in alterations to the bacterium that interact with lung innate immunity resulting in enhanced bacterial clearance.

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Several primary sources of publicly available, quantitative dose-response data from traditional toxicology study designs relevant to predictive toxicology applications are now available, including the redeveloped U.S. Environmental Protection Agency's Toxicity Reference Database (ToxRefDB v2.

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Safety assessment for cosmetic-relevant chemicals (CRCs) in the European Union has been reshaped by restrictions on animal testing, and new approach methodologies (NAMs) for predicting toxicity are critical to ensure new cosmetic product safety. To demonstrate NAMs for safety assessment, we surveyed in vitro bioactivity and in vivo systemic toxicity data in the US Environmental Protection Agency's (EPA's) Toxicity Forecaster (ToxCast) and Toxicity Reference databases (ToxRefDB), respectively, for 58 chemicals identified as CRCs, including cosmetic ingredients as well as trace contaminants. CRCs were diverse in use types as suggested by broad chemical use categories.

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Article Synopsis
  • The Toxicity Reference Database (ToxRefDB) aggregates information from over 5000 in vivo toxicity studies to create a public resource aimed at improving predictive modeling.
  • The latest version, ToxRefDBv2, includes structured annotations for various toxicity study designs, showcasing which endpoints were tested or not.
  • Enhanced data quality through standardized vocabulary and cross-referencing with the United Medical Language System significantly boosts the utility of ToxRefDBv2 for toxicology research.
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Linking in vitro bioactivity and in vivo toxicity on a dose basis enables the use of high-throughput in vitro assays as an alternative to traditional animal studies. In this study, we evaluated assumptions in the use of a high-throughput, physiologically based toxicokinetic (PBTK) model to relate in vitro bioactivity and rat in vivo toxicity data. The fraction unbound in plasma (fup) and intrinsic hepatic clearance (Clint) were measured for rats (for 67 and 77 chemicals, respectively), combined with fup and Clint literature data for 97 chemicals, and incorporated in the PBTK model.

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Malnutrition is prevalent in cirrhosis. Vitamin and mineral deficiencies, including vitamin D, vitamin A, and zinc, are common and have been shown to correlate with survival. Our aim was to review the mechanisms of vitamin D, vitamin A, and zinc deficiencies in cirrhosis and the clinical assessment of affected patients, their outcomes based on the current literature, and management.

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Hyperglycemia is a common complication after ischemic stroke, but its link to worse outcome is not well understood. We hypothesized that hyperglycemia may reflect an impaired metabolic response that is associated with worse cytotoxic brain injury. We performed retrospective analysis of magnetic resonance imaging from a cohort of acute ischemic stroke patients prospectively collected from 2006 to 2010 with baseline demographic and laboratory data as well as three-month outcomes.

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Background And Purpose: Matrix metalloproteinase-9 (MMP-9) is elevated in patients with acute stroke who later develop hemorrhagic transformation (HT). It is controversial whether early fluid-attenuated inversion recovery (FLAIR) hyperintensity on brain MRI predicts hemorrhagic transformation (HT). We assessed whether FLAIR hyperintensity was associated with MMP-9 and HT.

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Background: Brain edema is a serious complication of ischemic stroke that can lead to secondary neurological deterioration and death. Glyburide is reported to prevent brain swelling in preclinical rodent models of ischemic stroke through inhibition of a non-selective channel composed of sulfonylurea receptor 1 and transient receptor potential cation channel subfamily M member 4. However, the relevance of this pathway to the development of cerebral edema in stroke patients is not known.

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