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1.
Medicine (Baltimore) ; 103(19): e38110, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38728478

ABSTRACT

RATIONAL: The Philadelphia chromosome (Ph) is seen in most patients with chronic myeloid leukemia and some patients with acute lymphoblastic leukemia. However, Ph-positive acute myeloid leukemia (Ph + AML) is a rare entity with a poor prognosis and a short median survival period. To date, there have been few clinical reports on this disease. And the treatment regimen of this disease has not been uniformly determined. PATIENT CONCERNS: We report a case of a Ph + AML. A 32-year-old male who was admitted to our hospital with weakness for 2 months. DIAGNOSIS: Philadelphia chromosome-positive acute myeloid leukemia. INTERVENTIONS: The patient achieved complete remission by the administration of a tyrosine kinase inhibitor, combined with low-intensity chemotherapy and a B-cell lymphoma 2 inhibitor. Then, allogeneic hematopoietic stem cell transplantation (allo-HSCT) from his sister was successfully performed. OUTCOMES: The patient has been in a continuous remission state for 6 months after transplantation. LESSONS: We reported a rare Ph + AML case, successfully treated with allo-HSCT. This case provided strong support for treating Ph + AML with allo-HSCT.


Subject(s)
Hematopoietic Stem Cell Transplantation , Leukemia, Myeloid, Acute , Philadelphia Chromosome , Humans , Male , Hematopoietic Stem Cell Transplantation/methods , Adult , Leukemia, Myeloid, Acute/therapy , Leukemia, Myeloid, Acute/genetics , Transplantation, Homologous , Remission Induction
2.
ChemSusChem ; : e202400454, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38702899

ABSTRACT

Nitromethane is used a common solvent, stabilizer, and fuel additive. Nitromethane has also been used as a sustainable building block and convenient reagent in chemical synthesis. In this Minireview, we summarize the recent advances in activation of nitromethane, using nitromethane as the source of cyano group, nitrogen, methylamine, formyl group, C1, nitroso, and oxime.

3.
Toxicol Mech Methods ; 34(5): 517-526, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38293967

ABSTRACT

Fine particulate matter (PM2.5) increases the risks of lung cancer. Epigenetics provides a new toxicology mechanism for the adverse health effects of PM2.5. However, the regulating mechanisms of PM2.5 exposure on candidate gene DNA methylation changes in the development of lung cancer remain unclear. Abnormal expression of the glutathione S transferase (GST) gene is associated with cancer. However, the relationship between PM2.5 and DNA methylation-mediated GST gene expression is not well understood. In this study, we performed GST DNA methylation analysis and GST-related gene expression in human A549 cells exposed to PM2.5 (0, 50, 100 µg/mL, from Taiyuan, China) for 24 h (n = 4). We found that PM2.5 may cause DNA oxidative damage to cells and the elevation of GSTP1 promotes cell resistance to reactive oxygen species (ROS). The Kelch-1ike ECH-associated protein l (Keap1)/nuclear factor NF-E2-related factor 2 (Nrf2) pathway activates the GSTP1. The decrease in the DNA methylation level of the GSTP1 gene enhances GSTP1 expression. GST DNA methylation is associated with reduced levels of 5-methylcytosine (5mC), DNA methyltransferase 1 (DNMT1), and histone deacetylases 3 (HDAC3). The GSTM1 was not sensitive to PM2.5 stimulation. Our findings suggest that PM2.5 activates GSTP1 to defend PM2.5-induced ROS and 8-hydroxy-deoxyguanosine (8-OHdG) formation through the Keap1/Nrf2 signaling pathway and GSTP1 DNA methylation.


Subject(s)
DNA Methylation , Glutathione S-Transferase pi , Kelch-Like ECH-Associated Protein 1 , NF-E2-Related Factor 2 , Oxidative Stress , Particulate Matter , Signal Transduction , Humans , Kelch-Like ECH-Associated Protein 1/metabolism , Kelch-Like ECH-Associated Protein 1/genetics , NF-E2-Related Factor 2/metabolism , NF-E2-Related Factor 2/genetics , DNA Methylation/drug effects , Oxidative Stress/drug effects , Particulate Matter/toxicity , A549 Cells , Signal Transduction/drug effects , Glutathione S-Transferase pi/genetics , Glutathione S-Transferase pi/metabolism , Glutathione Transferase/metabolism , Glutathione Transferase/genetics , Reactive Oxygen Species/metabolism , DNA Damage/drug effects , Air Pollutants/toxicity
4.
ChemSusChem ; 17(10): e202400028, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38225209

ABSTRACT

New methods and strategies for the direct oxidation of benzylic C-H bonds are highly desirable, owing to the importance of ketone motifs in significant organic transformations and the synthesis of valuable molecules, including pharmaceuticals, pesticides, and fine chemicals. Herein, we describe an electrochemical benzylic C-H oxidation strategy for the synthesis of ketones using MeOH as an oxygen source. Inexpensive and safe KBr serves as both an electrolyte and a bromide radical precursor in the reaction. This transformation also offers several advantages such as mild conditions, broad functional group tolerance, and operational simplicity. Mechanistic investigations by control experiments, radical scavenging experiments, electron paramagnetic resonance (EPR), kinetic studies, cyclic voltammetry (CV), and in-situ Fourier transform infrared (FTIR) spectroscopy support a pathway involving the formation and transformation of benzyl methyl ether via hydrogen atom transfer (HAT) and single-electron transfer (SET). The practical application of our strategy is highlighted by the successful synthesis of five pharmaceuticals, namely lenperone, melperone, diphenhydramine, cinnarizine, and flunarizine.

5.
Toxicol Res (Camb) ; 12(6): 1105-1112, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38145098

ABSTRACT

Background: Formaldehyde (FA) is a common environmental pollutant that has been found to cause negative cardiovascular effects, however, the toxicological mechanism is not well understood. In this study, we investigated the molecular effects of the Nitric Oxide (NO)/cyclic Guanosine Monophosphate (cGMP) signaling pathway and L-type calcium (L-Ca2+) channels in rat hearts. Methods: We designed the short-term FA exposure on the rat heart in different concentrations (0, 0.5, 3, 18 mg/m3). After 7 days of exposure, the rats were sacrificed and the rat tissues were removed for various experiments. Results: Our experimental data showed that FA resulted in the upregulation NO and cGMP, especially at 18 mg/m3. Further, when exposed to high concentrations of FA, Cav1.2 and Cav1.3 expression decreased. We conclude that the NO/cGMP signaling pathway and downstream related channels can be regulated by increasing the production of NO in the low concentration group of FA. High concentration FA directly regulates L-Ca22+ channels. Conclusion: This study suggests that FA damages the function of the cardiovascular system by regulating the NO/cGMP signaling pathway and L-Ca2+ channels.

6.
Angew Chem Int Ed Engl ; 62(32): e202304434, 2023 Aug 07.
Article in English | MEDLINE | ID: mdl-37340694

ABSTRACT

Activation of nitromethane to endow new reactivity is an interesting and meaningful but also challenging topic. Herein, we report an electrochemical activation of nitromethane to serve as both the heterocyclic skeleton and oxime sources for the construction of isoxazoline aldoximes. The isoxazoline aldoximes that are prepared by four steps with the reported strategy are synthesized in a single step from low-cost and readily available nitromethane and olefins with moderate to excellent yields under our electrochemical conditions. The reaction also takes advantage of high atom-economy and E-selectivity. Moreover, the mechanism is studied by control experiments, a kinetic isotope effect (KIE) study, cyclic voltammogram (CV) experiments, and density functional theory (DFT) calculations. The mechanistic results reveal that nitromethane may be activated under electrochemical conditions to deliver a 1,2,5-oxadiazole 2-oxide intermediate, which undergoes [3+2] cycloaddition with olefins to yield isoxazoline aldoximes.

7.
Environ Sci Pollut Res Int ; 30(35): 84002-84010, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37353701

ABSTRACT

Amphiphilic blue-fluorescence carbon dots (B-CDs) were synthesized via pyrolysis method with citric acid and oleamine as precursors. B-CDs are monodispersed in ethanol, toluene, and ultrapure water with the average particle sizes of 3.33 nm, 2.05 nm, and 4.12 nm, respectively. The maximum emission wavelength of the B-CDs excitation at 370 nm is located at 459 nm. The B-CDs have good optical properties with excellent photostability. The fluorescence quantum yield (QY) of the as-prepared CDs is as high as 30.17%. The fluorescence of B-CDs is quenched because of static quenching by oxytetracycline. A high selective and sensitive fluorescence probe for detecting oxytetracycline was constructed with a linear range of 1.52-27.60 µg/mL and the detection limit of 0.33 µg/mL. The B-CDs-based fluorescence probe can be applied to analyze oxytetracycline in milk; the recoveries and relative standard are satisfactory. Furthermore, the B-CDs were exploited for imaging of SH-SY5Y cells. The results demonstrate that as-synthesized CDs can serve as a cellular imaging reagent owing to remarkable bioimaging performance. This work provides a new strategy for the detection of oxytetracycline in food.


Subject(s)
Neuroblastoma , Oxytetracycline , Quantum Dots , Humans , Animals , Fluorescent Dyes , Carbon , Milk , Pyrolysis , Spectrometry, Fluorescence
8.
J Org Chem ; 88(2): 1128-1134, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36583715

ABSTRACT

Herein, we report a new approach to methylenation of alcohols using N-methyl amide as a sustainable methylene reagent; the N-methyl delivers the methylene group. This new reagent is easily prepared and stable to both air and moisture. Furthermore, the final byproduct of this methylene reagent can be recycled in excellent yields and then reused in methylenation reactions upon treating with CH3I.


Subject(s)
Alcohols , Methane , Indicators and Reagents , Catalysis
9.
Nonlinear Dyn ; 110(3): 2913-2929, 2022.
Article in English | MEDLINE | ID: mdl-35936507

ABSTRACT

In the pandemic of COVID-19, there are exposed individuals who are infected but lack distinct clinical symptoms. In addition, the diffusion of related information drives aware individuals to spontaneously seek resources for protection. The special spreading characteristic and coevolution of different processes may induce unexpected spreading phenomena. Thus we construct a three-layered network framework to explore how information-driven resource allocation affects SEIS (susceptible-exposed-infected-susceptible) epidemic spreading. The analyses utilizing microscopic Markov chain approach reveal that the epidemic threshold depends on the topology structure of epidemic network and the processes of information diffusion and resource allocation. Conducting extensive Monte Carlo simulations, we find some crucial phenomena in the coevolution of information diffusion, resource allocation and epidemic spreading. Firstly, when E-state (exposed state, without symptoms) individuals are infectious, long incubation period results in more E-state individuals than I-state (infected state, with obvious symptoms) individuals. Besides, when E-state individuals have strong or weak infectious capacity, increasing incubation period has an opposite effect on epidemic propagation. Secondly, the short incubation period induces the first-order phase transition. But enhancing the efficacy of resources would convert the phase transition to a second-order type. Finally, comparing the coevolution in networks with different topologies, we find setting the epidemic layer as scale-free network can inhibit the spreading of the epidemic.

10.
Front Plant Sci ; 13: 921245, 2022.
Article in English | MEDLINE | ID: mdl-35795348

ABSTRACT

Dodder (Cuscuta spp.) species are obligate parasitic flowering plants that totally depend on host plants for growth and reproduction and severely suppress hosts' growth. As a rootless and leafless plant, excised dodder shoots exhibit rapid growth and elongation for several days to hunt for new host stems, and parasitization could be reestablished. This is one unique ability of the dodder to facilitate its success in nature. Clearly, excised dodder stems have to recycle stored nutrients to elongate as much as possible. However, the mechanism of stored nutrient recycling in the in vitro dodder shoots is still poorly understood. Here, we found that dodder is a carbohydrate-rich holoparasitic plant. During the in vitro dodder shoot development, starch was dramatically and thoroughly degraded in the dodder shoots. Sucrose derived from starch degradation in the basal stems was transported to the shoot tips, in which EMP and TCA pathways were activated to compensate for carbon demand for the following elongation according to the variations of sugar content related to the crucial gene expression, and the metabolomics analysis. Additionally, antioxidants were significantly accumulated in the shoot tips in contrast to those in the basal stems. The variations of phytohormones (jasmonic acid, indole-3-acetic acid, and abscisic acid) indicated that they played essential roles in this process. All these data suggested that starch and sucrose degradation, EMP and TCA activation, antioxidants, and phytohormones were crucial and associated with the in vitro dodder shoot elongation.

11.
J Appl Stat ; 49(4): 902-925, 2022.
Article in English | MEDLINE | ID: mdl-35707815

ABSTRACT

Missing data and outliers usually arise in longitudinal studies. Ignoring the effects of missing data and outliers will make the classical generalized estimating equation approach invalid. The longitudinal cohort study of rheumatoid arthritis patients was designed to investigate whether the Health Assessment Questionnaire score was associated with baseline covariates and changed with time. There exist dropouts and outliers in the data. In order to analyze the data, we develop a robust estimating equation approach. To deal with the responses missing at random, we extend a doubly robust method. To achieve robustness against outliers, we utilize an outlier robust method, which corrects the bias induced by outliers through centralizing the covariate matrix in the estimating equation. The doubly robust method for dropouts is easy to combine with the outlier robust method. The proposed method has the property of robustness in the sense that the proposed estimator is not only doubly robust against model misspecification for dropouts when there is no outlier in the data, but also robust against outliers. Consistency and asymptotic normality of the proposed estimator are established under regularity conditions. A comprehensive simulation study and real data analysis demonstrate that the proposed estimator does have the property of robustness.

13.
Plant Sci ; 303: 110770, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33487354

ABSTRACT

Dodder is a holoparasitic flowering plant that re-establishes parasitism with the host when broken off from the host. However, how in vitro dodder shoots recycle stored nutrients to maintain growth for reparasitizing hosts is not well characterized. Here, the spatial and temporal distribution characteristics of carbohydrates and reactive oxygen species (ROS) were analysed to explore the mechanism of recycling stored nutrients in dodder shoots in vitro. Our results showed that in vitro dodder shoots grew actively for more than 10 d, while dry mass decreased continuously. During this process, the transcript levels and activities of amylases gradually increased until 2 d and then declined in basal stems, which induced starch degradation at the tissue, cellular and subcellular levels. Additionally, the distribution characteristics of H2O2 and the activities and transcript levels of antioxidant enzymes indicated that shoot tips exhibited more robust ROS-scavenging capacity, and basal stems maintained higher ROS accumulation. Comparative proteomics analysis revealed that starch in basal stems acted as an energy source, and the glycolysis, TCA cycle and pentose phosphate pathway represented the energy supply for shoot tip elongation with time. These results indicated that efficient nutrient recycling and ROS modulation facilitated the parasitism of dodder grown in vitro by promoting shoot elongation growth to reach the host.


Subject(s)
Antioxidants/metabolism , Carbon/metabolism , Cuscuta/growth & development , Plant Shoots/growth & development , Carbohydrate Metabolism , Cuscuta/metabolism , Cuscuta/ultrastructure , Microscopy, Electron, Transmission , Plant Shoots/metabolism , Plant Shoots/ultrastructure , Proteomics , Reactive Oxygen Species/metabolism
14.
Food Chem Toxicol ; 146: 111848, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33166671

ABSTRACT

Di-(2-ethylhexyl) phthalate (DEHP), which is widely used as an industrial plasticizer, may cause liver damage. Concomitantly, bad dietary habits can exacerbate the liver burden. In this study, high-fat diet (HFD)-fed rats were treated with DEHP (10, 100, or 300 mg/kg bw) for 5 weeks, and a biochemical method was adopted to detect serum lipid contents. Key metabolic genes and pathological changes were assessed by different methods (RT-PCR, Western Bloting, ELISA and HE staining). The rats which were exposed to DEHP at a dose of 10 mg/kg bw exhibited dyslipidemia and increased transcription of SREBP-1 and its target FAS, thereby prompting de novo lipogenesis, but they did not become obese. Instead, DEHP at a dose of 300 mg/kg bw elevated the levels of AMPK phosphorylation and the mRNA levels of PPAR-α, PGC-1α, CPT-1 and lipin-1 in the liver, which led to fatty acid oxidation. Additionally, DEHP at the highest dose increased the TNF-α mRNA expression in the liver. Based on these findings, we conclude that excess fatty acid oxidation might increase the inflammatory response. No toxic effects on hepatic function were observed. These findings suggest that different doses of DEHP have the potential to disturb hepatic metabolic imbalance in HFD-fed rats.


Subject(s)
Diethylhexyl Phthalate/toxicity , Lipid Metabolism/drug effects , Liver/drug effects , Liver/metabolism , Animals , Cell Proliferation , Diet, High-Fat , Fatty Acids , Hepatocytes/drug effects , Hepatocytes/metabolism , Inflammation/chemically induced , Male , Rats , Rats, Wistar
15.
Environ Sci Pollut Res Int ; 27(30): 37887-37893, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32617814

ABSTRACT

The purpose of this study was to determine the contents of 12 metals in obtainable chalk sticks and assess their associated health risk. Chalk stick samples from 16 factories were analyzed by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The results showed that 12 metals were detectable in white and colored chalks. The contents of Al, Fe, and Mg were in the range of 646.2-3909 µg/g, 408.8-2075.1 µg/g, and 125-6825.7 µg/g, respectively. Additionally, the levels of Cu, Pb, Mn, and Cr were ranked in the order of Cu>Cr>Pb>Mn, while the maximum levels of As, Ni, Cd, and Sn in all samples (9.90, 10.14, 7.27, and 6.08 µg/g, respectively) were relatively lower than those of other metals. Furthermore, the cumulative hazard index (HI) values of all metals and carcinogenic risk (CR) of As (1.12E-4), Ni (1.39E-4), and Cr (1.15E-4) for children were also higher than the threshold value (1.0E-6 to 1.0E-4), suggesting that chalk dust particles may exert adverse effects on children.


Subject(s)
Calcium Carbonate , Metals, Heavy/analysis , Child , Environmental Monitoring , Humans , Risk Assessment , Spectrum Analysis
16.
PLoS One ; 15(5): e0233503, 2020.
Article in English | MEDLINE | ID: mdl-32442184

ABSTRACT

Recently-emerged base editing technologies could create single base mutations at precise genomic positions without generation DNA double strand breaks. Herbicide resistant mutations have been successfully introduced to different plant species, including Arabidopsis, watermelon, wheat, potato and tomato via C to T (or G to A on the complementary strand) base editors (CBE) at the P197 position of endogenous acetolactate synthase (ALS) genes. Additionally, G to A conversion to another conserved amino acid S653 on ALS gene could confer tolerance to imidazolinone herbicides. However, no such mutation was successfully generated via CBE, likely due to the target C base is outside of the classic base editing window. Since CBE driven by egg cell (EC) specific promoter would re-edit the wild type alleles in egg cells and early embryos, we hypothesized the diversity of base editing outcomes could be largely increased at later generations to allow selection of desired herbicide resistant mutants. To test this hypothesis, we aimed to introduce C to T conversion to the complement strand of S653 codon at ALS gene, hosting a C at the 10th position within the 20-nt spacer sequence outside of the classic base editing window. While we did not detect base-edited T1 plants, efficient and diverse base edits emerged at later generations. Herbicide resistant mutants with different editing outcomes were recovered when T3 and T4 seeds were subject to herbicide selection. As expected, most herbicide resistant plants contained S653N mutation as a result of G10 to A10. Our results showed that CBE could create imidazolinone herbicide resistant trait in Arabidopsis and be potentially applied to crops to facilitate weed control.


Subject(s)
Arabidopsis/drug effects , Arabidopsis/genetics , Herbicide Resistance/genetics , Acetolactate Synthase/genetics , Amino Acid Substitution , Arabidopsis Proteins/genetics , Base Sequence , CRISPR-Cas Systems , DNA, Plant/genetics , Gene Editing , Genes, Plant , Herbicides/pharmacology , Imidazolines/pharmacology , Mutagenesis, Site-Directed , Plant Breeding , Plants, Genetically Modified/drug effects , Plants, Genetically Modified/genetics , Selection, Genetic , Weed Control
17.
Org Lett ; 22(12): 4583-4587, 2020 06 19.
Article in English | MEDLINE | ID: mdl-32315187

ABSTRACT

An unprecedented N-demethylation of N-methyl amides has been developed by use of N-fluorobenzenesulfonimide as an oxidant with the aid of a copper catalyst. The conversion of amides to carbinolamines involves successive single-electron transfer, hydrogen-atom transfer, and hydrolysis, and is accompanied by formation of N-(phenylsulfonyl)benzenesulfonamide. Carbinolamines spontaneously decompose to N-demethylated amides and formaldehyde, because of their inherent instability.

18.
Int J Mol Sci ; 21(5)2020 Mar 06.
Article in English | MEDLINE | ID: mdl-32155833

ABSTRACT

Modified gibberellin (GA) signaling leads to semi-dwarfism with low nitrogen (N) use efficiency (NUE) in crops. An understanding of GA-mediated N uptake is essential for the development of crops with improved NUE. The function of GA in modulating N uptake capacity and nitrate (NO3-) transporters (NRTs) was analyzed in the GA synthesis-deficient mutant zmga3ox grown under low (LN) and sufficient (SN) N conditions. LN significantly suppressed the production of GA1, GA3, and GA4, and the zmga3ox plants showed more sensitivity in shoots as well as LN stress. Moreover, the higher anthocyanin accumulation and the decrease of chlorophyll content were also recorded. The net NO3- fluxes and 15N content were decreased in zmga3ox plants under both LN and SN conditions. Exogenous GA3 could restore the NO3- uptake in zmga3ox plants, but uniconazole repressed NO3- uptake. Moreover, the transcript levels of ZmNRT2.1/2.2 were downregulated in zmga3ox plants, while the GA3 application enhanced the expression level. Furthermore, the RNA-seq analyses identified several transcription factors that are involved in the GA-mediated transcriptional operation of NRTs related genes. These findings revealed that GAs influenced N uptake involved in the transcriptional regulation of NRTs and physiological responses in maize responding to nitrogen supply.


Subject(s)
Gene Expression Regulation, Plant/drug effects , Gibberellins/pharmacology , Nitrogen/metabolism , Plant Proteins/metabolism , Plant Roots/physiology , Zea mays/physiology , Biological Transport , Phenotype , Plant Growth Regulators/pharmacology , Plant Proteins/genetics , Plant Roots/drug effects , Transcription Factors/genetics , Transcription Factors/metabolism , Zea mays/drug effects , Zea mays/metabolism
20.
Sensors (Basel) ; 19(4)2019 Feb 23.
Article in English | MEDLINE | ID: mdl-30813418

ABSTRACT

Recently, the demand for human activity recognition has become more and more urgent. It is widely used in indoor positioning, medical monitoring, safe driving, etc. Existing activity recognition approaches require either the location information of the sensors or the specific domain knowledge, which are expensive, intrusive, and inconvenient for pervasive implementation. In this paper, a human activity recognition algorithm based on SDAE (Stacking Denoising Autoencoder) and LightGBM (LGB) is proposed. The SDAE is adopted to sanitize the noise in raw sensor data and extract the most effective characteristic expression with unsupervised learning. The LGB reveals the inherent feature dependencies among categories for accurate human activity recognition. Extensive experiments are conducted on four datasets of distinct sensor combinations collected by different devices in three typical application scenarios, which are human moving modes, current static, and dynamic behaviors of users. The experimental results demonstrate that our proposed algorithm achieves an average accuracy of 95.99%, outperforming other comparative algorithms using XGBoost, CNN (Convolutional Neural Network), CNN + Statistical features, or single SDAE.

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