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1.
Nature ; 618(7965): 494-499, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37198493

ABSTRACT

Hydrodynamics accurately describe relativistic heavy-ion collision experiments well before local thermal equilibrium is established1. This unexpectedly rapid onset of hydrodynamics-which takes place on the fastest available timescale-is called hydrodynamization2-4. It occurs when an interacting quantum system is quenched with an energy density that is much greater than its ground-state energy density5,6. During hydrodynamization, energy gets redistributed across very different energy scales. Hydrodynamization precedes local equilibration among momentum modes5, which is local prethermalization to a generalized Gibbs ensemble7,8 in nearly integrable systems or local thermalization in non-integrable systems9. Although many theories of quantum dynamics postulate local prethermalization10,11, the associated timescale has not been studied experimentally. Here we use an array of one-dimensional Bose gases to directly observe both hydrodynamization and local prethermalization. After we apply a Bragg scattering pulse, hydrodynamization is evident in the fast redistribution of energy among distant momentum modes, which occurs on timescales associated with the Bragg peak energies. Local prethermalization can be seen in the slower redistribution of occupation among nearby momentum modes. We find that the timescale for local prethermalization in our system is inversely proportional to the momenta involved. During hydrodynamization and local prethermalization, existing theories cannot quantitatively model our experiment. Exact theoretical calculations in the Tonks-Girardeau limit12 show qualitatively similar features.

2.
Small ; 20(13): e2304150, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37964398

ABSTRACT

Rheumatoid arthritis (RA), a systemic autoimmune disease, poses a significant human health threat. Iguratimod (IGUR), a novel disease-modifying antirheumatic drug (DMARD), has attracted great attention for RA treatment. Due to IGUR's hydrophobic nature, there's a pressing need for effective pharmaceutical formulations to enhance bioavailability and therapeutic efficacy. The high-gravity nanoprecipitation technique (HGNPT) emerges as a promising approach for formulating poorly water-soluble drugs. In this study, IGUR nanodrugs (NanoIGUR) are synthesized using HGNPT, with a focus on optimizing various operational parameters. The outcomes revealed that HGNPT enabled the continuous production of NanoIGUR with smaller sizes (ranging from 300 to 1000 nm), more uniform shapes, and reduced crystallinity. In vitro drug release tests demonstrated improved dissolution rates with decreasing particle size and crystallinity. Notably, in vitro and in vivo investigations showcased NanoIGUR's efficacy in inhibiting synovial fibroblast proliferation, migration, and invasion, as well as reducing inflammation in collagen-induced arthritis. This study introduces a promising strategy to enhance and broaden the application of poorly water-soluble drugs.


Subject(s)
Antirheumatic Agents , Arthritis, Rheumatoid , Chromones , Nanoparticles , Sulfonamides , Humans , Polyvinyl Alcohol , Arthritis, Rheumatoid/drug therapy , Antirheumatic Agents/chemistry , Antirheumatic Agents/pharmacology , Antirheumatic Agents/therapeutic use , Water
3.
Magn Reson Med ; 91(5): 1923-1935, 2024 May.
Article in English | MEDLINE | ID: mdl-38098427

ABSTRACT

PURPOSE: To demonstrate a novel MR elastography (MRE) technique, termed here wavelet MRE. With this technique, broadband motion sensitivity is achievable. Moreover, the true tissue displacement can be reconstructed with a simple inverse transform. METHODS: A wavelet MRE sequence was developed with motion-encoding gradients based on Haar wavelets. From the phase images' displacement was estimated using an inverse transform. Simulations were performed using a frequency sweep and a transient as ground-truth motions. A PVC phantom was scanned using wavelet MRE and standard MRE with both transient (one and 10 cycles of 90-Hz motion) and steady-state dual-frequency motion (30 and 60 Hz) for comparison. The technique was tested in a human brain, and motion trajectories were estimated for each voxel. RESULTS: In simulation, the displacement information estimated from wavelet MRE closely matched the true motion. In the phantom test, the MRE phase data generated from the displacement information derived from wavelet MRE agreed well with standard MRE data. Testing of wavelet MRE to assess transient motion waveforms in the brain was successful, and the tissue motion observed was consistent with a previous study. CONCLUSION: The uniform and broadband frequency response of wavelet MRE makes it a promising method for imaging transient, multifrequency motion, or motion with unknown frequency content. One potential application is measuring the response of brain tissue undergoing low-amplitude, transient vibrations as a model for the study of traumatic brain injury.


Subject(s)
Elasticity Imaging Techniques , Magnetic Resonance Imaging , Humans , Magnetic Resonance Imaging/methods , Elasticity Imaging Techniques/methods , Algorithms , Brain/diagnostic imaging , Phantoms, Imaging , Sound
4.
Langmuir ; 40(17): 9134-9143, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38636482

ABSTRACT

Wound healing has been a persistent clinical challenge for a long time. Electrical stimulation is an effective therapy with the potential to accelerate wound healing. In this work, the self-powered electrospun nanofiber membranes (triples) were constructed as multifunctional wound dressings with electrical stimulation and biochemical capabilities. Triple was composed of a hydrolyzable inner layer with antiseptic and hemostatic chitosan, a hydrophilic core layer loaded with conductive AgNWs, and a hydrophobic outer layer fabricated by self-powered PVDF. Triple exhibited presentable wettability and acceptable moisture permeability. Electrical performance tests indicated that triple can transmit electrical signals formed by the piezoelectric effect to the wound. High antibacterial activities were observed for triple against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, with inhibition rates of 96.52, 98.63, and 97.26%, respectively. In vitro cell assays demonstrated that triple cells showed satisfactory proliferation and mobility. A whole blood clotting test showed that triple can enhance hemostasis. The innovative self-powered multifunctional fibers presented in this work offer a promising approach to addressing complications and expediting the promotion of chronic wound healing.


Subject(s)
Anti-Bacterial Agents , Escherichia coli , Nanofibers , Pseudomonas aeruginosa , Staphylococcus aureus , Wound Healing , Wound Healing/drug effects , Nanofibers/chemistry , Staphylococcus aureus/drug effects , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Escherichia coli/drug effects , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/physiology , Chitosan/chemistry , Humans , Animals , Cell Proliferation/drug effects
6.
Arch Toxicol ; 98(6): 1919-1935, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38584193

ABSTRACT

Human liver-derived metabolically competent HepaRG cells have been successfully employed in both two-dimensional (2D) and 3D spheroid formats for performing the comet assay and micronucleus (MN) assay. In the present study, we have investigated expanding the genotoxicity endpoints evaluated in HepaRG cells by detecting mutagenesis using two error-corrected next generation sequencing (ecNGS) technologies, Duplex Sequencing (DS) and High-Fidelity (HiFi) Sequencing. Both HepaRG 2D cells and 3D spheroids were exposed for 72 h to N-nitrosodimethylamine (NDMA), followed by an additional incubation for the fixation of induced mutations. NDMA-induced DNA damage, chromosomal damage, and mutagenesis were determined using the comet assay, MN assay, and ecNGS, respectively. The 72-h treatment with NDMA resulted in concentration-dependent increases in cytotoxicity, DNA damage, MN formation, and mutation frequency in both 2D and 3D cultures, with greater responses observed in the 3D spheroids compared to 2D cells. The mutational spectrum analysis showed that NDMA induced predominantly A:T → G:C transitions, along with a lower frequency of G:C → A:T transitions, and exhibited a different trinucleotide signature relative to the negative control. These results demonstrate that the HepaRG 2D cells and 3D spheroid models can be used for mutagenesis assessment using both DS and HiFi Sequencing, with the caveat that severe cytotoxic concentrations should be avoided when conducting DS. With further validation, the HepaRG 2D/3D system may become a powerful human-based metabolically competent platform for genotoxicity testing.


Subject(s)
Comet Assay , DNA Damage , Dimethylnitrosamine , High-Throughput Nucleotide Sequencing , Micronucleus Tests , Mutagens , Humans , Dimethylnitrosamine/toxicity , Comet Assay/methods , Micronucleus Tests/methods , Mutagens/toxicity , DNA Damage/drug effects , Spheroids, Cellular/drug effects , Mutagenicity Tests/methods , Cell Culture Techniques , Cell Line , Hepatocytes/drug effects , Mutagenesis/drug effects , Mutation , Dose-Response Relationship, Drug
7.
Langmuir ; 39(37): 13109-13120, 2023 Sep 19.
Article in English | MEDLINE | ID: mdl-37672621

ABSTRACT

Controlled pesticide delivery systems offer many distinctive advantages over conventional pesticide formulations. In this work, degradable poly(N-isopropylacrylamide) (PNIPAM)-tannic acid (TA) microgels and multifunctional PDA@PNIPAM-TA nanocomposites were prepared in a high-gravity rotating packed bed reactor (RPB) for smart pesticide delivery and release. The as-prepared microgels and nanocomposites showed reversible temperature-dependent swelling/deswelling behavior and irreversible pH-induced degradation. A dynamic contact angle test suggested that the introduction of TA and PDA into the PNIPAM matrix could enhance foliar adhesion and deposition efficiency. The nanocomposites were further used for the encapsulation and delivery of imidacloprid (IMI) to protect it from rapid photolysis and improve its pest-control efficiency. Their thermoresponsive behavior as well as pesticide loading capacity could be tuned by tailoring the PNIPAM-TA shell thickness, which could be varied by the NIPAM amount. The release rate of IMI from the core/shell nanocomposites was positively correlated with environmental temperature and near-infrared (NIR) light, which was adaptive to the positive temperature-dependent toxicity correlation of IMI and the increasing trend of pests under high temperature. The cumulative release of IMI was 23.5% at 25 °C, while it was 81.2% at 40 °C after 24 h of incubation, and the release rate was greatly enhanced under NIR irradiation. The results indicated that the facile control of pesticide release could be realized by regulating environmental conditions. This work also provides an idea for using high-gravity technology to conveniently construct a smart, effective, and environmentally friendly pesticide delivery system for sustainable crop protection.

8.
Bioorg Chem ; 138: 106619, 2023 09.
Article in English | MEDLINE | ID: mdl-37253310

ABSTRACT

Three new diterpenoids with an unusual carbon skeleton, pedilanins A-C (1-3), and nine new jatrophane diterpenoids, pedilanins D-L (4-12), along with five known ones (13-17), were isolated from Pedilanthus tithymaloides. Compounds 1-3 characterize an unprecedented tricyclo[10.3.0.02,9]pentadecane skeleton. Compounds 4-8 are rare examples of the jatrophanes bearing a cyclic hemiketal substructure. Their structures were determined by an extensive analysis of HRESIMS, NMR, quantum-chemical calculation, DP4+ probability, and X-ray crystallographic data. In the bioassay, compounds 1-12 dramatically reversed multidrug resistance in cancer cells with the fold-reversals ranging from 17.9 to 396.8 at the noncytotoxic concentration of 10 µM. The mechanism results indicated that compounds 2 and 3 inhibited the P-glycoprotein (Pgp) transporter function, thus reversing the drug resistance.


Subject(s)
Diterpenes , Euphorbia , Molecular Structure , Euphorbia/chemistry , Drug Resistance, Multiple , Radiopharmaceuticals/pharmacology , Diterpenes/pharmacology , Diterpenes/chemistry
9.
Arch Toxicol ; 97(4): 1163-1175, 2023 04.
Article in English | MEDLINE | ID: mdl-36847820

ABSTRACT

The in vitro micronucleus (MN) assay is a component of most test batteries used in assessing potential genotoxicity. Our previous study adapted metabolically competent HepaRG cells to the high-throughput (HT) flow-cytometry-based MN assay for genotoxicity assessment (Guo et al. in J Toxicol Environ Health A 83:702-717, 2020b, https://doi.org/10.1080/15287394.2020.1822972 ). We also demonstrated that, compared to HepaRG cells grown as two-dimensional (2D) cultures, 3D HepaRG spheroids have increased metabolic capacity and improved sensitivity in detecting DNA damage induced by genotoxicants using the comet assay (Seo et al. in ALTEX 39:583-604, 2022, https://doi.org/10.14573/altex.22011212022 ). In the present study, we have compared the performance of the HT flow-cytometry-based MN assay in HepaRG spheroids and 2D HepaRG cells by testing 34 compounds, including 19 genotoxicants or carcinogens and 15 compounds that show different genotoxic responses in vitro and in vivo. 2D HepaRG cells and spheroids were exposed to the test compounds for 24 h, followed by an additional 3- or 6-day incubation with human epidermal growth factor to stimulate cell division. The results demonstrated that HepaRG spheroids showed generally higher sensitivity in detecting several indirect-acting genotoxicants (require metabolic activation) compared to 2D cultures, with 7,12-dimethylbenzanthracene and N-nitrosodimethylamine inducing higher % MN formation along with having significantly lower benchmark dose values for MN induction in 3D spheroids. These data suggest that 3D HepaRG spheroids can be adapted to the HT flow-cytometry-based MN assay for genotoxicity testing. Our findings also indicate that integration of the MN and comet assays improved the sensitivity for detecting genotoxicants that require metabolic activation. These results suggest that HepaRG spheroids may contribute to New Approach Methodologies for genotoxicity assessment.


Subject(s)
DNA Damage , Mutagens , Humans , Micronucleus Tests/methods , Mutagens/toxicity , Comet Assay/methods , Mutagenicity Tests/methods
10.
Regul Toxicol Pharmacol ; 141: 105410, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37210026

ABSTRACT

Propranolol is a widely used ß-blocker that can generate a nitrosated derivative, N-nitroso propranolol (NNP). NNP has been reported to be negative in the bacterial reverse mutation test (the Ames test) but genotoxic in other in vitro assays. In the current study, we systematically examined the in vitro mutagenicity and genotoxicity of NNP using several modifications of the Ames test known to affect the mutagenicity of nitrosamines, as well as a battery of genotoxicity tests using human cells. We found that NNP induced concentration-dependent mutations in the Ames test, both in two tester strains that detect base pair substitutions, TA1535 and TA100, as well as in the TA98 frameshift-detector strain. Although positive results were seen with rat liver S9, the hamster liver S9 fraction was more effective in bio-transforming NNP into a reactive mutagen. NNP also induced micronuclei and gene mutations in human lymphoblastoid TK6 cells in the presence of hamster liver S9. Using a panel of TK6 cell lines that each expresses a different human cytochrome P450 (CYP), CYP2C19 was identified as the most active enzyme in the bioactivation of NNP to a genotoxicant among those tested. NNP also induced concentration-dependent DNA strand breakage in metabolically competent 2-dimensional (2D) and 3D cultures of human HepaRG cells. This study indicates that NNP is genotoxic in a variety of bacterial and mammalian systems. Thus, NNP is a mutagenic and genotoxic nitrosamine and a potential human carcinogen.


Subject(s)
Mutagens , Propranolol , Rats , Animals , Cricetinae , Humans , Mutagens/toxicity , Propranolol/toxicity , Mutation , DNA Damage , Mutagenesis , Mutagenicity Tests/methods , Mammals
11.
Ren Fail ; 45(1): 2192285, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36950854

ABSTRACT

BACKGROUND: Previous studies have shown that perioperative dexmedetomidine could reduce the incidence of postoperative AKI in cardiovascular surgery, however, its effectiveness in the non-cardiovascular surgery patient population has not been reported. The aim of this study was to investigate the effect of intraoperative dexmedetomidine on the incidence of postoperative AKI and postoperative ICU admissions in patients undergoing non-cardiovascular surgery. DESIGN AND SETTING: A single-center retrospective cohort study obtained from the database of the Center for Anesthesia and Surgery, the Third Xiangya Hospital. PATIENTS: Inpatients between 18 and 75 years of age who were admitted to our hospital for non-cardiovascular surgery from 2012 to 2019. RESULTS: Overall 2391 patients who used dexmedetomidine intraoperatively were analyzed in comparison to 4552 patients who did not use dexmedetomidine after one-to-two matching. The two cohorts had similar baseline values and demographic characteristics. The incidence of AKI was lower in patients with intraoperative dexmedetomidine use than in the nonuse group (OR 0.60, p < .001). The rate of severe renal failure needing dialysis was also lower than in the nonuse group (ß = -0.02, p < .05). After adjusting for confounding factors, the rate of AKI was still lower in the dexmedetomidine group. The rate of postoperative ICU admissions and in-hospital deaths were similar in the two groups (p > .05). CONCLUSION: For non-cardiovascular surgery patient population, intraoperative use of dexmedetomidine was associated with a lower incidence and less severity of postoperative AKI. However, there was no significant correlation with postoperative ICU occupancy or in-hospital mortality. Further prospective RCTs are needed in the future.


Subject(s)
Acute Kidney Injury , Cardiac Surgical Procedures , Dexmedetomidine , Humans , Dexmedetomidine/adverse effects , Incidence , Retrospective Studies , Cardiac Surgical Procedures/adverse effects , Acute Kidney Injury/epidemiology , Acute Kidney Injury/etiology , Acute Kidney Injury/prevention & control
12.
BMC Med ; 20(1): 17, 2022 01 21.
Article in English | MEDLINE | ID: mdl-35057816

ABSTRACT

BACKGROUND: With the recent certification by World Health Organization that the People's Republic of China is malaria-free, it is timely to consider how elimination of malaria was completed in People's Republic of China over the last 7 decades. Of the four widespread species of human malaria, Plasmodium vivax was the last to be eliminated by the national program of China. Understanding the incubation periods and relapses patterns of P. vivax through historical data from China is relevant for planning disease elimination in other malaria-endemic countries, with residual P. vivax malaria. METHODS: We collated data from both published and unpublished malaria parasite inoculation experiments conducted between 1979 and 1988 with parasites from different regions of the People's Republic of China. The studies had at least two years of follow-up. We categorized P. vivax incubation patterns via cluster analysis and investigated relapse studies by adapting a published within-host relapse model for P. vivax temperate phenotypes. Each model was fitted using the expectation-maximization (EM) algorithm initialized by hierarchical model-based agglomerative clustering. RESULTS: P. vivax parasites from the seven studies of five southern and central provinces in the People's Republic of China covering geographies ranging from the south temperate to north tropical zones. The parasites belonged to two distinct phenotypes: short- (10-19 days) or long-incubation (228-371 days). The larger the sporozoite inoculation, the more likely short incubation periods were observed, and with more subsequent relapses (Spearman's rank correlation between the number of inoculated sporozoites and the number of relapses of 0.51, p-value = 0.0043). The median of the posterior distribution for the duration of the first relapse interval after primary infection was 168.5 days (2.5% quantile: 89.7; 97.5% quantile: 227.69 days). The predicted survival proportions from the within-host model fit well to the original relapse data. The within-host model also captures the hypnozoite activation rates and relapse frequencies, which consequently influences the transmission possibility of P. vivax. CONCLUSIONS: Through a within-host model, we demonstrate the importance of clearance of hypnozoites. A strategy of two rounds of radical hypnozoite clearance via mass drug administration (MDA) deployed during transmission (summer and autumn) and non-transmission (late spring) seasons had a pronounced effect on outbreaks during the malaria epidemics in China. This understanding can inform malaria control strategies in other endemic countries with similar settings.


Subject(s)
Malaria, Vivax , Malaria , Animals , China/epidemiology , Disease Eradication , Humans , Malaria, Vivax/drug therapy , Malaria, Vivax/epidemiology , Malaria, Vivax/prevention & control , Plasmodium vivax , Recurrence , Sporozoites
13.
Small ; 18(14): e2107534, 2022 04.
Article in English | MEDLINE | ID: mdl-35182016

ABSTRACT

Alzheimer disease (AD) is the leading cause of dementia that affects millions of old people. Despite significant advances in the understanding of AD pathobiology, no disease modifying treatment is available. MicroRNA-124 (miR-124) is the most abundant miRNA in the normal brain with great potency to ameliorate AD-like pathology, while it is deficient in AD brain. Herein, the authors develop a DNA nanoflowers (DFs)-based delivery system to realize exogenous supplementation of miR-124 for AD therapy. The DFs with well-controlled size and morphology are prepared, and a miR-124 chimera is attached via hybridization. The DFs are further modified with RVG29 peptide to simultaneously realize brain-blood barrier (BBB) penetration and neuron targeting. Meanwhile, Rutin, a small molecular ancillary drug, is co-loaded into the DFs structure via its intercalation into the double stranded DNA region. Interestingly, Rutin could synergize miR-124 to suppress the expression of both BACE1 and APP, thus achieving a robust inhibition of amyloid ß generation. The nanosystem could pro-long miR-124 circulation in vivo, promote its BBB penetration and neuron targeting, resulting in a significant increase of miR-124 in the hippocampus of APP/PS1 mice and robust therapeutic efficacy in vivo. Such a bio-derived therapeutic system shows promise as a biocompatible nanomedicine for AD therapy.


Subject(s)
Alzheimer Disease , MicroRNAs , Alzheimer Disease/drug therapy , Amyloid Precursor Protein Secretases/genetics , Amyloid Precursor Protein Secretases/metabolism , Amyloid Precursor Protein Secretases/therapeutic use , Amyloid beta-Peptides/metabolism , Animals , Aspartic Acid Endopeptidases/genetics , Aspartic Acid Endopeptidases/metabolism , Aspartic Acid Endopeptidases/therapeutic use , Brain/metabolism , DNA/metabolism , Disease Models, Animal , Humans , Mice , Mice, Transgenic , MicroRNAs/metabolism , Neurons/metabolism , Rutin/metabolism , Rutin/pharmacology , Rutin/therapeutic use
14.
J Transl Med ; 20(1): 426, 2022 09 23.
Article in English | MEDLINE | ID: mdl-36138468

ABSTRACT

BACKGROUND: Long non-coding RNAs (lncRNAs) are closely related to the occurrence and development of cancer. Abnormally expressed lncRNA can be used as a diagnostic marker for cancer. In this study, we aim to investigate the clinical significance of MIR99AHG expression in lung adenocarcinoma (LUAD), and its biological roles in LUAD progression. METHODS: The relative expression of MIR99AHG in LUAD tissues and cell lines was analyzed using public databases and RT-qPCR. The biological functions of MIR99AHG were investigated using a loss-of-function approach. The effect of MIR99AHG on lung fibrosis was assessed by scratch assay, invasion assay and lung fibrosis rat model. FISH, luciferase reporter assay and immunofluorescence were performed to elucidate the underlying molecular mechanisms. RESULTS: LncRNA MIR99AHG expression level was downregulated in LUAD tissues and cell lines. Low MIR99AHG levels were associated with poorer patient overall survival. Functional analysis showed that MIR99AHG is associated with the LUAD malignant phenotype in vitro and in vivo. Further mechanistic studies showed that, MIR99AHG functions as a competitive endogenous RNA (ceRNA) to antagonize miR-136-5p-mediated ubiquitin specific protease 4 (USP4) degradation, thereby unregulated the expression of angiotensin-converting enzyme 2 (ACE2), a downstream target gene of USP4, which in turn affected alveolar type II epithelial cell fibrosis and epithelial-mesenchymal transition (EMT). In summary, the MIR99AHG/miR-136-5p/USP4/ACE2 signalling axis regulates lung fibrosis and EMT, thus inhibiting LUAD progression. CONCLUSION: This study showed that downregulated MIR99AHG leads to the development of pulmonary fibrosis. Therefore, overexpression of MIR99AHG may provide a new approach to preventing LUAD progression.


Subject(s)
Adenocarcinoma , Lung Neoplasms , MicroRNAs , Pulmonary Fibrosis , RNA, Long Noncoding , Adenocarcinoma/genetics , Angiotensin-Converting Enzyme 2 , Animals , Apoptosis/genetics , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Epithelial-Mesenchymal Transition/genetics , Gene Expression Regulation, Neoplastic , Lung Neoplasms/pathology , MicroRNAs/genetics , MicroRNAs/metabolism , Pulmonary Fibrosis/genetics , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Rats , Ubiquitin-Specific Proteases/genetics , Ubiquitin-Specific Proteases/metabolism
15.
Arch Toxicol ; 96(11): 3077-3089, 2022 11.
Article in English | MEDLINE | ID: mdl-35882637

ABSTRACT

Many nitrosamines are recognized as mutagens and potent rodent carcinogens. Over the past few years, nitrosamine impurities have been detected in various drugs leading to drug recalls. Although nitrosamines are included in a 'cohort of concern' because of their potential human health risks, most of this concern is based on rodent cancer and bacterial mutagenicity data, and there are little data on their genotoxicity in human-based systems. In this study, we employed human lymphoblastoid TK6 cells transduced with human cytochrome P450 (CYP) 2A6 to evaluate the genotoxicity of six nitrosamines that have been identified as impurities in drug products: N-nitrosodiethylamine (NDEA), N-nitrosoethylisopropylamine (NEIPA), N-nitroso-N-methyl-4-aminobutanoic acid (NMBA), N-nitrosomethylphenylamine (NMPA), N-nitrosodiisopropylamine (NDIPA), and N-nitrosodibutylamine (NDBA). Using flow cytometry-based assays, we found that 24-h treatment with NDEA, NEIPA, NMBA, and NMPA caused concentration-dependent increases in the phosphorylation of histone H2A.X (γH2A.X) in CYP2A6-expressing TK6 cells. Metabolism of these four nitrosamines by CYP2A6 also caused significant increases in micronucleus frequency as well as G2/M phase cell-cycle arrest. In addition, nuclear P53 activation was found in CYP2A6-expressing TK6 cells exposed to NDEA, NEIPA, and NMPA. Overall, the genotoxic potency of the six nitrosamine impurities in our test system was NMPA > NDEA ≈ NEIPA > NMBA > NDBA ≈ NDIPA. This study provides new information on the genotoxic potential of nitrosamines in human cells, complementing test results generated from traditional assays and partially addressing the issue of the relevance of nitrosamine genotoxicity for humans. The metabolically competent human cell system reported here may be a useful model for risk assessment of nitrosamine impurities found in drugs.


Subject(s)
Histones , Nitrosamines , Amides , Carcinogens/metabolism , Carcinogens/toxicity , Cytochrome P-450 Enzyme System/metabolism , DNA Damage , Diethylnitrosamine/toxicity , Humans , Mutagens/toxicity , Nitrosamines/toxicity , Propionates , Tumor Suppressor Protein p53 , gamma-Aminobutyric Acid
16.
J Appl Toxicol ; 42(9): 1491-1502, 2022 09.
Article in English | MEDLINE | ID: mdl-35261072

ABSTRACT

Black cohosh extract (BCE) is one of the most popular botanical products for relieving menopausal symptoms. However, recent studies indicate that BCE is not only ineffective for menopausal therapy but also induces genotoxicity through an aneugenic mode of action (MoA). In this study, the cytotoxicity of five constituents of BCE was evaluated in human lymphoblastoid TK6 cells. Among the five constituents, actein (up to 50 µM) showed the highest cytotoxicity and was thus selected for further genotoxicity evaluations. Actein caused DNA damage proportionally to concentration as evidenced by the phosphorylation of the histone protein H2A.X (γH2A.X) and resulted in chromosomal damage as measured by the increased percentage of micronuclei (%MN) in cells. In addition, actein activated DNA damage response (DDR) pathway through induction of p-ATM, p-Chk1, and p-Chk2, which subsequently induced cell cycle changes and apoptosis. Moreover, both BCE and actein increased intracellular reactive oxygen species (ROS) production, decreased glutathione levels, and activated the mitogen-activated protein kinases (MAPK) signaling pathway. N-acetylcysteine, a ROS scavenger, attenuated BCE- and actein-induced ROS production, apoptosis, and DNA damage. These findings indicate that BCE- and actein-induced genotoxicity is mediated, at least partially, through oxidative stress. Taken together, our data show that actein is likely one of the major contributors to BCE-induced genotoxicity.


Subject(s)
Cimicifuga , Cimicifuga/metabolism , Cimicifuga/toxicity , DNA Damage , Humans , Plant Extracts , Reactive Oxygen Species/metabolism , Saponins , Triterpenes
17.
Sensors (Basel) ; 22(19)2022 Oct 10.
Article in English | MEDLINE | ID: mdl-36236786

ABSTRACT

The single-beam bathymetric light detection and ranging (LiDAR) system 1 (SBLS-1), which is equipped with a 532-nm-band laser projector and two concentric-circle receivers for shallow- and deep-water echo signals, is a lightweight and convenient prototype instrument with low energy consumption. In this study, a novel LiDAR bathymetric method is utilized to achieve single-beam and dual-channel bathymetric characteristics, and an adaptive extraction method is proposed based on the cumulative standard deviation of the peak and trough, which is mainly used to extract the signal segment and eliminate system and random noise. To adapt the dual-channel bathymetric mechanism, an automatic channel-selection method was used at various water depths. A minimum half-wavelength Gaussian iterative decomposition is proposed to improve the detection accuracy of the surface- and bottom-water waveform components and ensure bathymetric accuracy and reliability. Based on a comparison between the experimental results and in situ data, it was found that the SBLS-1 obtained a bathymetric accuracy and RMSE of 0.27 m and 0.23 m at the Weifang and Qingdao test fields. This indicates that the SBLS-1 was bathymetrically capable of acquiring a reliable, high-efficiency waveform dataset. Hence, the novel LiDAR bathymetric method can effectively achieve high-accuracy near-shore bathymetry.

18.
Opt Express ; 29(2): 2411-2430, 2021 Jan 18.
Article in English | MEDLINE | ID: mdl-33726437

ABSTRACT

In nearshore bathymetry based on the Ice, Cloud, and Land Elevation Satellite-2 (ICESat-2), water refraction causes a position displacement of the seafloor signal photon, decreasing the bathymetric accuracy. A novel refraction-correction method is proposed for the ICESat-2. Based on the experimental results and statistical analysis, it is illustrated that the displacement in elevation direction reaches several meters at the relative depth. The displacement in the along- and cross-track directions is very small, ranging from millimeters to centimeters. Finally, the relationship of refraction displacements with various incident angles and water depths is analyzed in detail, revealing the nearshore bathymetry characteristics of ICESat-2.

19.
Biosci Biotechnol Biochem ; 85(12): 2383-2391, 2021 Nov 24.
Article in English | MEDLINE | ID: mdl-34601561

ABSTRACT

Sepsis-induced cardiomyopathy (SIC) is a major complication of sepsis. SET and MYND domain containing 1 (SMYD1) has central importance in heart development, and its role in SIC has not been identified. Herein, we found that the expression of SMYD1 was downregulated in myocardial tissues of SIC patients (from GEO database: GSE79962) and lipopolysaccharide (LPS)-induced SIC rats, and LPS-induced H9c2 cardiomyocytes. We used LPS-stimulated H9c2 cells that mimic sepsis in vitro to explore the function of SMYD1 in SIC. MTT assay, LDH and CK-MB release assay, flow cytometry, and ELISA assay showed that SMYD1 overexpression enhanced cell viability, alleviated cell injury, impeded apoptosis, and reduced the level of proinflammatory factors and NF-κB activation under the condition of LPS stimulation. Moreover, SMYD1 exerted protective effect on H9c2 cells stimulated with LPS through relieving endoplasmic reticulum (ER) stress. In conclusion, overexpression of SMYD1 alleviates cardiac injury through relieving ER stress during sepsis.


Subject(s)
Endoplasmic Reticulum Stress
20.
BMC Anesthesiol ; 21(1): 193, 2021 07 19.
Article in English | MEDLINE | ID: mdl-34281529

ABSTRACT

BACKGROUND: This study aims to investigate the risk factors of perioperative neurocognitive disorders (PNDs) mainly including postoperative cognitive dysfunction (POCD) in elderly patients with gastrointestinal tumors, and evaluate its predictive value. METHODS: A total of 222 eligible elderly patients (≥65 years) scheduled for elective gastroenterectomy under general anesthesia were enrolled. The cognitive function assessment was carried out 1 day before surgery and 7 days after surgery. Receiver operating characteristic curve analysis was performed to evaluate the predictive value of risk factors for early POCD. The risk factors for POCD were analyzed using univariate and multivariate logistic regression model. RESULTS: Of all the 222 enrolled patients, 91 (41.0%) developed early POCD and 40 (18.0%) were identified as major POCD within 7 days after the surgery. Visual analogue score (VAS, 1st day, resting) ≥4 (OR = 7.618[3.231-17.962], P < 0.001) and alcohol exposure (OR = 2.398[1.174-4.900], P = 0.016) were independent risk factors for early POCD. VAS score (1st, resting) ≥4 (OR = 13.823[4.779-39.981], P < 0.001), preoperative white blood cell (WBC) levels ≥10 × 10*9/L (OR = 5.548[1.128-26.221], P = 0.035), blood loss ≥500 ml (OR = 3.317[1.094-10.059], P = 0.034), history of hypertension (OR = 3.046[1.267-7.322], P = 0.013), and neutrophil-lymphocyte ratio (NLR) ≥2 (OR = 3.261[1.020-10.419], P = 0.046) were independent risk factors for major POCD. Receiver operating characteristic curve analysis indicated that VAS score (1st day, resting) was a significant predictor for major POCD with a cut-off value of 2.68 and an area under the curve of 0.860 (95% confidence interval: 0.801-0.920, P < 0.001). CONCLUSIONS: The risk factors for early POCD after gastroenterectomy included high VAS score (1st day, resting) and alcohol exposure. High VAS score, preoperative WBC levels ≥10 × 10*9/L, blood loss ≥500 ml, NLR ≥2, and history of hypertension were independent risk factors for major POCD. Among them, VAS score was one of the important predictors.


Subject(s)
Digestive System Surgical Procedures/methods , Gastrointestinal Neoplasms/surgery , Neurocognitive Disorders/epidemiology , Postoperative Cognitive Complications/epidemiology , Aged , Anesthesia, General/methods , Female , Gastrectomy/methods , Humans , Hypertension/epidemiology , Male , Neurocognitive Disorders/etiology , Predictive Value of Tests , Retrospective Studies , Risk Factors
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