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1.
Chem Biodivers ; 21(7): e202400900, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38713316

ABSTRACT

A new compound xylarkarynone A (1), a first reported natural product compound xylarkarynone B (2) and eight known compounds (3-10) were isolated from Xylaria sp. HHY-2. Their structures were elucidated by spectroscopic methods, DP4+ probability analyses and electronic circular dichroism (ECD) calculations. The bioactivities of isolated compounds were assayed. Compound 1 exhibited obvious activity against A549 cells with an IC50 value of 6.12±0.28 µM. Additionally, compound 1 showed moderate antifungal activities against Plectosphaerella cucumerina and Aspergillus niger with minimum inhibitory concentrations (MICs) of both 16 µg/mL, which was at the same grade with positive control nystatin. Most compounds exhibited varying degrees of inhibitory activity against P. cucumerina, indicating that Xylaria sp. has potential as inhibitors against P. cucumerina.


Subject(s)
Antifungal Agents , Aspergillus niger , Microbial Sensitivity Tests , Sesquiterpenes , Xylariales , Humans , Xylariales/chemistry , Antifungal Agents/pharmacology , Antifungal Agents/chemistry , Antifungal Agents/isolation & purification , Sesquiterpenes/chemistry , Sesquiterpenes/isolation & purification , Sesquiterpenes/pharmacology , Aspergillus niger/drug effects , A549 Cells , Drug Screening Assays, Antitumor , Ascomycota/chemistry , Molecular Structure , Molecular Conformation , Structure-Activity Relationship , Dose-Response Relationship, Drug
2.
J Biochem Mol Toxicol ; 37(8): e23380, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37132394

ABSTRACT

Chemoresistance remains a major obstacle to the treatment of esophageal cancer (EC). Exosome-mediated transfer of long noncoding RNAs (lncRNAs) has recently been unveiled to correlate with the regulation of drug resistance in EC. This study aimed to investigate the physiological mechanisms by which exosome-encapsulated lncRNA myocardial infarction-associated transcript (MIAT) derived from tumor cells might mediate the paclitaxel (PTX) resistance of EC cells. First, MIAT was experimentally determined to be upregulated in PTX nonresponders and PTX-resistant EC cells. Silencing of MIAT in PTX-resistant EC cells decreased cell viability and enhanced apoptosis, corresponding to a reduced half-maximal inhibitory concentration (IC50 ) value. Next, exosomes were isolated from EC109 and EC109/T cells, and EC109 cells were cocultured with EC109/T-cell-derived exosomes. Accordingly, MIAT was revealed to be transmitted through exosomes from EC109/T cells to EC109 cells. Tumor-derived exosomes carrying MIAT increased the IC50 value of PTX and suppressed apoptosis in EC109 cells to promote PTX resistance. Furthermore, MIAT promoted the enrichment of TATA-box binding protein-associated Factor 1 (TAF1) in the promoter region of sterol regulatory element binding transcription factor 1 (SREBF1), as shown by a chromatin immunoprecipitation assay. This might be the mechanism by which MIAT could promote PTX resistance. Finally, in vivo experiments further confirmed that the knockdown of MIAT attenuated the resistance of EC cells to PTX. Collectively, these results indicate that tumor-derived exosome-loaded MIAT activates the TAF1/SREBF1 axis to induce PTX resistance in EC cells, providing a potential therapeutic target for overcoming PTX resistance in EC.


Subject(s)
Esophageal Neoplasms , Exosomes , MicroRNAs , Myocardial Infarction , RNA, Long Noncoding , Humans , Paclitaxel/pharmacology , Exosomes/metabolism , Cell Line, Tumor , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/genetics , Esophageal Neoplasms/metabolism , RNA, Long Noncoding/genetics , MicroRNAs/genetics , Cell Proliferation , Sterol Regulatory Element Binding Protein 1
3.
J Environ Sci (China) ; 124: 187-197, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36182129

ABSTRACT

The temporal and spatial characteristics of urban river bacterial communities help us understand the feedback mechanism of bacteria to changes in the aquatic environment. The Fuhe River plays an important role in determining the water ecological environment of Baiyangdian Lake. 16S rRNA gene sequencing was used to study the microbial distribution characteristics in the Fuhe River in different seasons. The results showed that some environmental factors of the surface water (ammonia nitrogen (NH3-N), total nitrogen (TN), and total phosphorus (TP)) were different on the spatial and temporal scales. Moreover, there were no seasonal differences in the contents of TN, TP, total organic carbon (TOC), or heavy metals in the sediments. The distributions of Cyanobacteria, Actinomycetes and Firmicutes in the water and Actinomycetes and Planctomycetes in the sediments differed significantly among seasons (P < 0.05). There were significant spatial differences in bacteria in the surface water, with the highest abundance of Proteobacteria recorded in the river along with the highest nutrient concentration, while the abundance of Bacteroidetes was higher in the upstream than the downstream. Microbial communities in the water were most sensitive to temperature (T) and the TP concentration (P < 0.01). Moreover, differences in the bacterial community were better explained by the content of heavy metals in the sediments than by the chemical characteristics. A PICRUSt metabolic inference analysis showed that the effect of high summer temperatures on the enzyme action led to an increase in the abundances of the metabolic-related genes of the river microorganisms.


Subject(s)
Metals, Heavy , Microbiota , Ammonia/analysis , Bacteria/genetics , Carbon/analysis , China , Environmental Monitoring/methods , Geologic Sediments/chemistry , Metals, Heavy/analysis , Nitrogen/analysis , Phosphorus/analysis , RNA, Ribosomal, 16S/genetics , Water/analysis
4.
J Am Chem Soc ; 144(3): 1323-1331, 2022 01 26.
Article in English | MEDLINE | ID: mdl-35037455

ABSTRACT

As an aberrant base in DNA, uracil is generated by either deoxyuridine (dU) misincorporation or cytosine deamination, and involved in multiple physiological and pathological processes. Genome-wide profiles of uracil are important for study of these processes. Current methods for whole-genome mapping of uracil all rely on uracil-DNA N-glycosylase (UNG) and are limited in resolution, specificity, and/or sensitivity. Here, we developed a UdgX cross-linking and polymerase stalling sequencing ("Ucaps-seq") method to detect dU at single-nucleotide resolution. First, the specificity of Ucaps-seq was confirmed on synthetic DNA. Then the effectiveness of the approach was verified on two genomes from different sources. Ucaps-seq not only identified the enrichment of dU at dT sites in pemetrexed-treated cancer cells with globally elevated uracil but also detected dU at dC sites within the "WRC" motif in activated B cells which have increased dU in specific regions. Finally, Ucaps-seq was utilized to detect dU introduced by the cytosine base editor (nCas9-APOBEC) and identified a novel off-target site in cellular context. In conclusion, Ucaps-seq is a powerful tool with many potential applications, especially in evaluation of base editing fidelity.


Subject(s)
Nucleotides
5.
Mol Carcinog ; 61(12): 1177-1190, 2022 12.
Article in English | MEDLINE | ID: mdl-36239547

ABSTRACT

5-Fluorouracil (5-FU) resistance is one of the main causes for treatment failure in esophageal cancer (EC). Here, we intended to elucidate the mechanism of tumor-derived extracellular vesicles (TEVs)-encapsulated long noncoding RNAs (lncRNAs) AC116025.2 in 5-FU resistance in EC. EVs were isolated from the serum samples of EC patients and HEEC, TE-1, and TE-1/5-FU cells, followed by RT-qPCR detection of AC116025.2 expression in EVs. The relationship among AC116025.2, microRNA (miR)-4496, and SEMA5A was evaluated. Next, EC cells were cocultured with EVs, followed by lentivirus transduction and plasmid transfection for studying the role of TEVs-AC116025.2 in EC cells in relation to miR-4496 and SEMA5A. Tumor formation in nude mice was applied for in vivo confirmation. Elevated AC116025.2 expression was seen in the EVs from the serum of 5-FU insensitive patients and from 5-FU-resistant EC cells. Mechanistically, AC116025.2 bound to miR-4496 that inversely targeted SEMA5A in EC cells. EVs-oe-AC116025.2 augmented EC cell viability, colony formation, and 5-FU resistance, but diminished their apoptosis through miR-4496-mediated SEMA5A. Furthermore, EVs-oe-AC116025.2 augmented tumor formation and 5-FU resistance of EC cells in vivo. Conclusively, our data offered evidence of the promoting mechanism of TEVs in the 5-FU resistance of EC by delivering AC116025.2.


Subject(s)
Esophageal Neoplasms , Extracellular Vesicles , MicroRNAs , RNA, Long Noncoding , Mice , Animals , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Fluorouracil/pharmacology , Mice, Nude , Gene Expression Regulation, Neoplastic , MicroRNAs/genetics , MicroRNAs/metabolism , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/genetics , Esophageal Neoplasms/metabolism , Extracellular Vesicles/genetics , Extracellular Vesicles/metabolism , Drug Resistance, Neoplasm/genetics , Cell Line, Tumor
6.
Chem Biodivers ; 19(12): e202200671, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36373236

ABSTRACT

A new highly oxygenated polyketide derivative, trichodersine (1), together with fourteen known compounds (2-15) were isolated from Trichoderma sp. MWTGP-04. The structure of trichodersine (1) was established based on comprehensive spectroscopic data analysis, and biogenesis argument. The results of double culture experiments indicated that the strain exhibited potential antifungal activity. The antifungal activities of all isolated compounds were evaluated, among them compound 1 exhibited remarkable antifungal activities against Fusarium solani, Plectosphaerella cucumerina, Alternaria panax, and Aspergillus niger, with minimum inhibitory concentrations (MICs) of 4, 4, 16, and 32 µg/mL, respectively. In addition, the antifungal experiments of polyketide derivatives (1-3) disclosed that their degree of oxidation was a key factor affecting the antifungal activity.


Subject(s)
Polyketides , Trichoderma , Antifungal Agents/chemistry , Trichoderma/chemistry , Polyketides/pharmacology , Aspergillus niger , Microbial Sensitivity Tests
7.
Sensors (Basel) ; 22(13)2022 Jul 01.
Article in English | MEDLINE | ID: mdl-35808474

ABSTRACT

The temperature and pressure of seawater are of great importance to investigate the environmental evolution for the research of ocean science. With this regard, we proposed and experimentally demonstrated a seawater temperature and pressure sensor realized by a polyimide (PI) tube-based Fabry-Perot interferometer (FPI) together with a fiber Bragg grating (FBG). Benefiting from the higher thermo-optical coefficient and larger elasticity of polymer than the fused silica fiber, the sensitivity of the sensor is largely improved. The FBG is used to compensate the cross effect of the temperature. The measured temperature and pressure sensitivities of the sensor are 18.910 nm/°C and -35.605 nm/MPa, respectively. Furthermore, the temperature and pressure information measured by the sensor can be achieved simultaneously using the sensitivity matrix method. In addition, the proposed sensor has advantages of easy fabrication, compact size, as well as capability of multiplexing and long-distance measurement, making it competitive and promising during the marine monitoring.


Subject(s)
Fiber Optic Technology , Interferometry , Fiber Optic Technology/methods , Polymers , Silicon Dioxide , Temperature
8.
J Cell Mol Med ; 25(23): 10879-10891, 2021 12.
Article in English | MEDLINE | ID: mdl-34716659

ABSTRACT

N6 -methyladenosine (m6 A) is the most prevalent modification in mRNA and engages in multiple biological processes. Previous studies indicated that m6 A methyltransferase METTL3 ('writer') and demethylase FTO ('eraser') play critical roles in heart-related disease. However, in the heart, the function of m6 A 'reader', such as YTH (YT521-B homology) domain-containing proteins remains unclear. Here, we report that the defect in YTHDC1 but not other YTH family members contributes to dilated cardiomyopathy (DCM) in mice. Cardiac-specific conditional Ythdc1 knockout led to obvious left ventricular chamber enlargement and severe systolic dysfunction. YTHDC1 deficiency also resulted in the decrease of cardiomyocyte contractility and disordered sarcomere arrangement. By means of integrating multiple high-throughput sequence technologies, including m6 A-MeRIP, RIP-seq and mRNA-seq, we identified 42 transcripts as potential downstream targets of YTHDC1. Amongst them, we found that Titin mRNA was decorated with m6 A modification and depletion of YTHDC1 resulted in aberrant splicing of Titin. Our study suggests that Ythdc1 plays crucial role in regulating the normal contractile function and the development of DCM. These findings clarify the essential role of m6 A reader in cardiac biofunction and provide a novel potential target for the treatment of DCM.


Subject(s)
Cardiomyopathy, Dilated/metabolism , Methyltransferases/metabolism , Nerve Tissue Proteins/metabolism , Protein Kinases/metabolism , RNA Splicing Factors/metabolism , Adenosine/metabolism , Animals , Connectin/metabolism , Male , Mice , RNA-Binding Proteins/metabolism , Serine-Arginine Splicing Factors/metabolism
9.
Anal Chem ; 93(23): 8178-8187, 2021 06 15.
Article in English | MEDLINE | ID: mdl-34061502

ABSTRACT

Imaging of lipids of whole-body specimens in two-dimensional (2D) analysis provides a global picture of the lipid changes in lipid-disturbed diseases, enabling a better understanding of lipid functions and lipid-modulation processes in different organs. However, 2D imaging of a single cross section can hardly characterize the whole-body lipid alterations. In this work, a three-dimensional matrix-assisted laser desorption/ionization mass spectrometry imaging (3D MALDI-MSI) approach was developed for analysis of whole-body zebrafish, for the first time, and applied to identify altered lipids and map their spatial distributions by using a zebrafish model of Niemann-Pick disease type C1 (NPC1), a neurovisceral lipid storage disorder causing both neurodegenerative disorder and visceral organ damage. The constructed 3D fish model provided comprehensive information on the 3D distribution of lipids of interest and allowed direct correlations between these lipids and organs of the fish. Obtained results revealed that several sphingolipids and phospholipids showed significant alterations and exhibited different localization patterns in various organs such as the brain, spinal cord, intestines, and liver-spleen region in the npc1 gene mutant fish compared to those of the wild type. The whole-body 3D MALDI-MSI approach revealed unique lipid signatures for different NPC1-affected organs, which might offer insights into the link between the impaired lipid storage and subsequent clinical symptoms, such as neurodegeneration and hepatosplenomegaly.


Subject(s)
Niemann-Pick Disease, Type C , Zebrafish , Animals , Imaging, Three-Dimensional , Niemann-Pick Disease, Type C/diagnostic imaging , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Sphingolipids
10.
Appl Opt ; 60(28): 8904-8909, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34613118

ABSTRACT

A Sagnac loop interferometer based on concatenated polarization-maintaining fiber (PMF) tapers is proposed for simultaneous measurement of seawater salinity and temperature. The influences of the distance between the PMF tapers as well as fiber taper diameter on sensor performance have been investigated. Experimental results indicate that the fabricated sensor with a distance of 3 cm between adjacent fiber tapers possesses the salinity and temperature sensitivities of 0.367 nm/% and -0.728nm/∘C, respectively, and the taper waist diameter of 20 µm would help to improve salinity sensitivity in comparison with a sensor of 30 µm in diameter. The proposed Sagnac loop interferometer based on concatenated PMF tapers is expected to find potential applications in the measurement of seawater salinity.

11.
Sci Total Environ ; 914: 169919, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38199361

ABSTRACT

Di-2-ethylhexyl phthalate (DEHP), a widely utilized plasticizer, has been described as a potential obesogen based on in vivo disruption of hepatic lipid homeostasis and in vitro promotion of lipid accumulation. However, limited literature exists regarding the specific ramifications of DEHP exposure on obese individuals, and the precise mechanisms underlying the adverse effects of DEHP exposure remain unclear. This study aimed to assess the impact of DEHP on hepatic lipid metabolism in obese mice by comparing them to normal mice. Following a 10-week DEHP exposure period, the obese mice exhibited higher blood lipid levels, more severe hepatic steatosis, and more infiltrations of inflammatory cells in liver tissue than normal mice. Interestingly, the body weight of the mice exhibited no significant alteration. In addition, transcriptomic analyses revealed that both lipogenesis and fatty acid oxidation contributed to hepatic lipid metabolism dysregulation following DEHP exposure. More specifically, alterations in the transcription of genes associated with hepatic lipid metabolism were linked to the different responses to DEHP exposure observed in normal and obese mice. Additionally, the outcomes of in vitro experiments validated the in vivo findings and demonstrated that DEHP exposure could modify hepatic lipid metabolism in normal mice by activating the LXR/SREBP-1c signaling pathway to promote lipogenesis. At the same time, DEHP exposure led to inhibition of the Camkkß/AMPK pathway to suppress ß-fatty acid oxidation. Conversely, in obese mice, DEHP exposure was found to be associated with the stimulation of both lipogenesis and fatty acid oxidation via activation of the LXR/SREBP-1c and PPAR-α signaling pathways, respectively. The findings presented in this study first elucidate the contrasting mechanisms underlying DEHP-induced liver damage in obese and normal mice, thereby offering valuable insights into the pathogenesis of DEHP-induced liver damage in individuals with obesity.


Subject(s)
Diethylhexyl Phthalate , Lipid Metabolism , Phthalic Acids , Animals , Mice , Diethylhexyl Phthalate/metabolism , Fatty Acids/metabolism , Lipids , Liver/metabolism , Mice, Obese , Obesity/chemically induced , Obesity/metabolism , Peroxisome Proliferator-Activated Receptors/metabolism , Signal Transduction , Sterol Regulatory Element Binding Protein 1/metabolism
12.
J Vis Exp ; (208)2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38912798

ABSTRACT

Accurate measurement of urinary parameters in awake mice is crucial for understanding lower urinary tract (LUT) dysfunction, particularly in conditions like neurogenic bladder post-traumatic spinal cord injury (SCI). However, conducting cystometry recordings in mice presents notable challenges. When mice are in a prone and restricted position during recording sessions, urine tends to be absorbed by the fur and skin, leading to an underestimation of voided volume (VV). The goal of this study was to enhance the accuracy of cystometry and external urethral sphincter electromyography (EUS-EMG) recordings in awake mice. We developed a unique method utilizing cyanoacrylate adhesive to create a waterproof skin barrier around the urethral meatus and abdomen, preventing urine absorption and ensuring precise measurements. Results show that after applying the cyanoacrylate, the sum of VV and RV remained consistent with the infused saline volume, and there were no wet areas observed post-experiment, indicating successful prevention of urine absorption. Additionally, the method simultaneously stabilized the electrodes connected with the external urethral sphincter (EUS), ensured stable electromyography (EMG) signals, and minimized artifacts caused by the movement of the awakened mouse and manipulation of the experimenter. Methodological details, results, and implications are discussed, highlighting the importance of improving urodynamic techniques in preclinical research.


Subject(s)
Electromyography , Urodynamics , Animals , Mice , Urodynamics/physiology , Electromyography/methods , Urethra/physiology , Female
13.
Heart Lung ; 66: 9-15, 2024.
Article in English | MEDLINE | ID: mdl-38518405

ABSTRACT

BACKGROUND: Global nonvalvular AF rises, impacting health severely. In Qinghai, China's diverse setting, studying AF among varied ethnic groups is crucial OBJECTIVES: The purpose of this study was to compares cardiac features in AF among Tibetan, Han, and Hui patients to develop tailored prevention and treatment strategies for this region, the goal was to enhance the understanding of AF and provide an empirical basis for developing prevention and treatment strategies specific to this region METHODS: This study included a total of 3445 Tibetan, Han, and Hui patients diagnosed with nonvalvular atrial fibrillation and treated at the Qinghai Cardiovascular and Cerebrovascular Specialist Hospital, China, between January 2019 and January 2021. We analyzed the differences in cardiac structure, comorbidities, and other influencing factors among the different ethnic groups RESULTS: We found significant differences in gender, age, smoking history, lone atrial fibrillation, left heart failure, dilated cardiomyopathy, and diabetes between Tibetan, Han, and Hui patients (P < 0.05). Tibetan, Han, and Hui patients also differed with regard to left ventricular end-diastolic volume, left ventricular ejection fraction, fractional shortening, NT-proBNP, glycated hemoglobin, red blood cell distribution width, platelet count, platelet hematocrit, platelet distribution width, homocysteine (Hcy), C-reactive protein, and superoxide dismutase (SOD) (P < 0.05) CONCLUSION: Our study revealed variations in comorbidities, cardiac structure, and blood indexes among Tibetan, Han, and Hui AF patients, highlighting distinct patterns in complications and biomarker levels across ethnic groups.


Subject(s)
Atrial Fibrillation , Aged , Female , Humans , Male , Middle Aged , Atrial Fibrillation/epidemiology , Atrial Fibrillation/ethnology , Atrial Fibrillation/complications , China/epidemiology , Ethnicity/statistics & numerical data , Retrospective Studies , Risk Factors , Tibet/epidemiology , Tibet/ethnology , East Asian People
14.
Cells ; 13(13)2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38995011

ABSTRACT

Unsuccessful axonal regeneration in transected spinal cord injury (SCI) is mainly attributed to shortage of growth factors, inhibitory glial scar, and low intrinsic regenerating capacity of severely injured neurons. Previously, we constructed an axonal growth permissive pathway in a thoracic hemisected injury by transplantation of Schwann cells overexpressing glial-cell-derived neurotrophic factor (SCs-GDNF) into the lesion gap as well as the caudal cord and proved that this novel permissive bridge promoted the regeneration of descending propriospinal tract (dPST) axons across and beyond the lesion. In the current study, we subjected rats to complete thoracic (T11) spinal cord transections and examined whether these combinatorial treatments can support dPST axons' regeneration beyond the transected injury. The results indicated that GDNF significantly improved graft-host interface by promoting integration between SCs and astrocytes, especially the migration of reactive astrocyte into SCs-GDNF territory. The glial response in the caudal graft area has been significantly attenuated. The astrocytes inside the grafted area were morphologically characterized by elongated and slim process and bipolar orientation accompanied by dramatically reduced expression of glial fibrillary acidic protein. Tremendous dPST axons have been found to regenerate across the lesion and back to the caudal spinal cord which were otherwise difficult to see in control groups. The caudal synaptic connections were formed, and regenerated axons were remyelinated. The hindlimb locomotor function has been improved.


Subject(s)
Axons , Glial Cell Line-Derived Neurotrophic Factor , Nerve Regeneration , Schwann Cells , Spinal Cord Injuries , Animals , Spinal Cord Injuries/metabolism , Spinal Cord Injuries/therapy , Spinal Cord Injuries/pathology , Spinal Cord Injuries/physiopathology , Schwann Cells/metabolism , Glial Cell Line-Derived Neurotrophic Factor/metabolism , Glial Cell Line-Derived Neurotrophic Factor/genetics , Axons/metabolism , Rats , Rats, Sprague-Dawley , Female , Astrocytes/metabolism
15.
Nat Prod Res ; 38(1): 85-90, 2024.
Article in English | MEDLINE | ID: mdl-35913407

ABSTRACT

Nine diterpenoid alkaloids were isolated from Aconitum georgei Comber belonging to the genus Aconitum in Ranunculaceae family. Their structures were determinated by using HR-ESI-MS and 1 D/2D NMR spectra as geordine (1), yunaconitine (2), chasmanine (3), crassicauline A (4), forestine (5), pseudaconine (6), 14-acetylalatisamine (7), austroconitine B (8), and talatisamine (9). Among them, compound 1 is a previously undescribed aconitine-type C19-diterpenoid alkaloid, and compounds 3, and 5-9 have not previously been isolated from this species. The results of in vitro experiments indicated that new compound 1 possesses mild anti-inflammatory activity, which inhibited the production of NO in LPS-activated RAW 264.7 cells with an inhibition ratio of 29.75% at 50 µM.


Subject(s)
Aconitum , Alkaloids , Diterpenes , Drugs, Chinese Herbal , Aconitum/chemistry , Alkaloids/chemistry , Magnetic Resonance Spectroscopy , Drugs, Chinese Herbal/chemistry , Diterpenes/chemistry , Molecular Structure , Plant Roots/chemistry
16.
Int J Nanomedicine ; 19: 7473-7492, 2024.
Article in English | MEDLINE | ID: mdl-39071504

ABSTRACT

Background: Gigantocellular reticular nucleus (GRNs) executes a vital role in locomotor recovery after spinal cord injury. However, due to its unique anatomical location deep within the brainstem, intervening in GRNs for spinal cord injury research is challenging. To address this problem, this study adopted an extracorporeal magnetic stimulation system to observe the effects of selective magnetic stimulation of GRNs with iron oxide nanoparticles combined treadmill training on locomotor recovery after spinal cord injury, and explored the possible mechanisms. Methods: Superparamagnetic iron oxide (SPIO) nanoparticles were stereotactically injected into bilateral GRNs of mice with moderate T10 spinal cord contusion. Eight-week selective magnetic stimulation produced by extracorporeal magnetic stimulation system (MSS) combined with treadmill training was adopted for the animals from one week after surgery. Locomotor function of mice was evaluated by the Basso Mouse Scale, Grid-walking test and Treadscan analysis. Brain MRI, anterograde virus tracer and immunofluorescence staining were applied to observe the tissue compatibility of SPIO in GRNs, trace GRNs' projections and evaluate neurotransmitters' expression in spinal cord respectively. Motor-evoked potentials and H reflex were collected for assessing the integrity of cortical spinal tract and the excitation of motor neurons in anterior horn. Results: (1) SPIO persisted in GRNs for a minimum of 24 weeks without inducing apoptosis of GRN cells, and degraded slowly over time. (2) MSS-enabled treadmill training dramatically improved locomotor performances of injured mice, and promoted cortico-reticulo-spinal circuit reorganization. (3) MSS-enabled treadmill training took superimposed roles through both activating GRNs to drive more projections of GRNs across lesion site and rebalancing neurotransmitters' expression in anterior horn of lumbar spinal cord. Conclusion: These results indicate that selective MSS intervention of GRNs potentially serves as an innovative strategy to promote more spared fibers of GRNs across lesion site and rebalance neurotransmitters' expression after spinal cord injury, paving the way for the structural remodeling of neural systems collaborating with exercise training, thus ultimately contributing to the reconstruction of cortico-reticulo-spinal circuit.


Subject(s)
Magnetic Iron Oxide Nanoparticles , Spinal Cord Injuries , Animals , Spinal Cord Injuries/therapy , Spinal Cord Injuries/physiopathology , Magnetic Iron Oxide Nanoparticles/chemistry , Mice , Locomotion/physiology , Recovery of Function/physiology , Spinal Cord , Physical Conditioning, Animal , Reticular Formation , Magnetic Field Therapy/methods , Mice, Inbred C57BL , Female , Evoked Potentials, Motor/physiology
17.
Phytochemistry ; : 114251, 2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39178977

ABSTRACT

Seven previously undescribed compounds, including one amino acid hybrid sesquiterpene areolatol A (1), two unusual natural sesquiterpenoid skeleton areolatones A-B (2-3) and four benzo[j]fluoranthene areolaranes A-D (4-7) were characterized from Annulohypoxylon areolatum. The structures of the compounds were determined by extensive spectroscopic analysis, X-ray diffraction analysis, and ECD and NMR computational. Notably, areolatol A (1) was the first reported sesquiterpene featuring a 5/7/3-ring system and hybridized with two molecular amino acids. In addition, areolaranes A-D (4-7) were identified as possible chemophenetic markers.

18.
Waste Manag ; 170: 270-277, 2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37729844

ABSTRACT

As a class of organic micropollutants of global concern, pharmaceuticals have prevalent distributions in the aqueous environment (e.g., groundwater and surface water) and solid matrices (e.g., soil, sediments, and dried sludge). Their contamination levels have been further aggravated by the annually increased production of expired drugs as emerging harmful wastes worldwide. Sulfate radicals (SO4•-)-based oxidation has attracted increasing attention for abating pharmaceuticals in the environment, whereas the transformation mechanisms of solid-phase pharmaceuticals remain unknown thus far. This investigation presented for the first time that SO4•-, individually produced by mechanical force-activated and heat-activated persulfate treatments, could effectively oxidize three model pharmaceuticals (i.e., methotrexate, sitagliptin, and salbutamol) in both solid and liquid phases. The high-resolution mass spectrometric analysis suggested their distinct transformation products formed by different phases of SO4•- oxidation. Accordingly, the SO4•--mediated mechanistic differences between the solid-phase and liquid-phase pharmaceuticals were proposed. It is noteworthy that the products from both systems were predicted with the remaining persistence, bioaccumulation, and multi-endpoint toxicity. Therefore, some post-treatment strategies need to be considered during practical applications of SO4•--based technologies in remediating different phases of micropollutants. This work has environmental implications for understanding the comparative transformation mechanisms of pharmaceuticals by SO4•- oxidation in remediating the contaminated solid and aqueous matrices.

19.
Water Res ; 246: 120741, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37864882

ABSTRACT

Anticancer drugs have raised worldwide concern owing to their ubiquitous occurrence and ecological risks, necessitating the development of efficient removal strategies in water and wastewater treatment. Although peroxymonosulfate (PMS) is known to be a promising chemical in water decontamination, limited information is available regarding the removal efficiency of anticancer drugs by PMS and solar/PMS systems. This study first reports the moiety-specific reaction kinetics and mechanisms of methotrexate (MTX), an anticancer drug with widespread attention, by PMS (unactivated) and solar-activated PMS in water. It was found that MTX abatement by the direct PMS oxidation followed second-order kinetics, and the pH-dependent rate constants increased from 0.4 M-1 s-1 (pH 5.0) to 1.3 M-1 s-1 (pH 8.0), with a slight decrease to 1.1 M-1 s-1 at pH 9.0. The presence of chloride and bromide exerted no obvious influence on the removal of MTX by PMS. Furthermore, the chemical reactivity of MTX and its seven substructures with different reactive species was evaluated, and the degradation contributions of the reactive species involved were quantitatively analyzed in the solar/PMS system. The product analysis suggested similar reaction pathways of MTX by PMS and solar/PMS systems. The persistence, bioaccumulation, and toxicity of the transformation products were investigated, indicating treatment-driven risks. Notably, MTX can be removed efficiently from both municipal and hospital wastewater effluents by the solar/PMS system, suggesting its great potential in wastewater treatment applications. Overall, this study systematically evaluated the elimination of MTX by the unactivated PMS and solar/PMS treatment processes in water. The obtained findings may have implications for the mechanistic understanding and development of PMS-based processes for the degradation of such micropollutants in wastewater.


Subject(s)
Antineoplastic Agents , Water Pollutants, Chemical , Methotrexate/analysis , Water/analysis , Wastewater , Peroxides/chemistry , Oxidation-Reduction , Water Pollutants, Chemical/chemistry , Kinetics
20.
Nanomaterials (Basel) ; 13(7)2023 Apr 06.
Article in English | MEDLINE | ID: mdl-37049386

ABSTRACT

As one of the widely studied semiconductor materials, titanium dioxide (TiO2) exhibits high photoelectrochemical (PEC) water-splitting performance as well as high chemical and photo stability. However, limited by a wide band gap and fast electron-hole recombination rate, the low solar-to-hydrogen conversion efficiency remains a bottleneck for the practical application of TiO2-based photoelectrodes. To improve the charge separation and water oxidation efficiency of TiO2 photoanodes, antimonene, a two-dimensional (2D) material obtained by liquid-phase exfoliation, was assembled onto TiO2 nanorod arrays (TNRAs) by a simple drop-coating assembly process. PEC measurements showed that the resulting 2D Sb/TiO2 photoelectrode displayed an enhanced photocurrent density of about 1.32 mA cm-2 in 1.0 M KOH at 0.3 V vs. Hg/HgO, which is ~1.65 times higher than that of the pristine TNRAs. Through UV-Vis absorption and electrochemical impedance spectroscopy measurements, it was possible to ascribe the enhanced PEC performances of the 2D Sb/TiO2 photoanode to increased absorption intensity in the visible light region, and improved interfacial charge-transfer kinetics in the 2D Sb/TiO2 heterojunction, which promotes electron-hole separation, transfer, and collection.

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