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1.
Biochem Biophys Res Commun ; 736: 150461, 2024 Aug 06.
Article in English | MEDLINE | ID: mdl-39128263

ABSTRACT

To understand why Chlamydia trachomatis (Ct) (L2/434/Bu) favors hypoxia, we examined the dynamics of infected cells using a glycolysis-related PCR array and metabolomic analysis, along with the perturbation of nucleotide synthesis. Our findings revealed that, compared to normoxia, hypoxia with infection significantly and selectively upregulates the expression of genes related to glycolysis, glycogen degradation, and the pentose phosphate pathway. Furthermore, hypoxia induced a significant decrease in metabolite levels, particularly methionine-related metabolites, independent of infection, indicating efficient metabolism under hypoxia. Additionally, the perturbation of nucleotide synthesis with adenosine derivatives impaired Ct growth. Collectively, our results suggest that Ct favors a hypoxic environment with efficient metabolism, in which Ct readily activates glycolysis responsible for stable nucleotide synthesis as well as ATP supply.

2.
Chembiochem ; : e202400311, 2024 Jul 22.
Article in English | MEDLINE | ID: mdl-39037826

ABSTRACT

Electron imaging of biological samples stained with heavy metals has enabled visualization of subcellular structures critical in chemical-, structural-, and neuro-biology. In particular, osmium tetroxide OsO4 has been widely adopted for selective lipid imaging. Despite the ubiquity of its use, the osmium speciation in lipid membranes and the process for contrast generation in electron microscopy (EM) have continued to be open questions, limiting efforts to improve staining protocols and therefore high-resolution nanoscale imaging of biological samples. Following our recent success using photoemission electron microscopy (PEEM) to image mouse brain tissues with synaptic resolution, we have used PEEM to determine the nanoscale electronic structure of Os-stained biological samples. Os(IV), in the form of OsO2, generates nanoaggregates in lipid membranes, leading to a strong spatial variation in the electronic structure and electron density of states. OsO2 has a metallic electronic structure that drastically increases the electron density of states near the Fermi level. Depositing metallic OsO2 in lipid membranes allows for strongly enhanced EM signals and conductivity of biological materials. The identification of the chemical species and understanding of the membrane contrast mechanism of Os-stained biological specimens provides a new opportunity for the development of staining protocols for high-resolution, high-contrast EM imaging.

3.
Nano Lett ; 23(7): 2677-2686, 2023 Apr 12.
Article in English | MEDLINE | ID: mdl-36917456

ABSTRACT

MXenes have the potential for efficient light-to-heat conversion in photothermal applications. To effectively utilize MXenes in such applications, it is important to understand the underlying nonequilibrium processes, including electron-phonon and phonon-phonon couplings. Here, we use transient electron and X-ray diffraction to investigate the heating and cooling of photoexcited MXenes at femtosecond to nanosecond time scales. Our results show extremely strong electron-phonon coupling in Ti3C2-based MXenes, resulting in lattice heating within a few hundred femtoseconds. We also systematically study heat dissipation in MXenes with varying film thicknesses, chemical surface terminations, flake sizes, and annealing conditions. We find that the thermal boundary conductance (TBC) governs the thermal relaxation in films thinner than the optical penetration depth. We achieve a 2-fold enhancement of the TBC, reaching 20 MW m-2 K-1, by controlling the flake size or chemical surface termination, which is promising for engineering heat dissipation in photothermal and thermoelectric applications of the MXenes.

4.
Environ Monit Assess ; 196(9): 809, 2024 Aug 13.
Article in English | MEDLINE | ID: mdl-39138752

ABSTRACT

Tea is a vital agricultural product in Taiwan. Due to global warming, the increasing extreme weather events have disrupted tea garden conditions and caused economic losses in agriculture. To address these challenges, a comprehensive tea garden risk assessment model, a Bayesian network (BN), was developed by considering various factors, including meteorological data, disaster events, tea garden environment (location, altitude, tea tree age, and soil characteristics), farming practices, and farmer interviews, and constructed risk assessment indicators for tea gardens based on the climate change risk analysis concept from the Intergovernmental Panel on Climate Change Fifth Assessment Report (IPCC AR5). The results demonstrated an accuracy of over 92% in both validating and testing the model for tea tree damage and yield reduction. Sensitivity analysis revealed that tea tree damage and yield reduction were mutually influential, with weather, fertilization, and irrigation also impacting tea garden risk. Risk analysis under climate change scenarios from various global climate models (GCMs) indicated that droughts may pose the highest risk with up to 41% and 40% of serious tea tree growth damage and tea yield reduction, respectively, followed by cold events that most tea gardens may have less than 20% chances of serious impacts on tea tree growth and tea yield reduction. The impacts of heavy rains get the least concern because all five tea gardens may not be affected in terms of tea tree growth and tea yield with large chances of 67 to 85%. Comparing farming methods, natural farming showed lower disaster risk than conventional and organic approaches. The tea plantation risk assessment model can serve as a valuable resource for analyzing and offering recommendations for tea garden disaster management and is used to assess the impact of meteorological disasters on tea plantations in the future.


Subject(s)
Bayes Theorem , Climate Change , Tea , Taiwan , Risk Assessment , Altitude , Camellia sinensis/growth & development , Agriculture , Gardens , Environmental Monitoring/methods
5.
Entropy (Basel) ; 26(4)2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38667849

ABSTRACT

The leakage flow has a significant impact on the aerodynamic losses and efficiency of the compressor. This paper investigates the loss mechanism in the tip region based on a high-load cantilevered stator cascade. Firstly, a high-fidelity flow field structure was obtained based on the Enhanced Delay Detached Eddy Simulation (EDDES) method. Subsequently, the Liutex method was employed to study the vortex structures in the tip region. The results indicate the presence of a tip leakage vortex (TLV), passage vortex (PV), and induced vortex (IV) in the tip region. At i=4°,8°, the induced vortex interacts with the PV and low-energy fluid, forming a "three-shape" mixed vortex. Finally, a qualitative and quantitative analysis of the loss sources in the tip flow field was conducted based on the entropy generation rate, and the impact of the incidence on the losses was explored. The loss sources in the tip flow field included endwall loss, blade profile loss, wake loss, and secondary flow loss. At i=0°, the loss primarily originated from the endwall and blade profile, accounting for 40% and 39%, respectively. As the incidence increased, the absolute value of losses increased, and the proportion of loss caused by secondary flow significantly increased. At i=8°, the proportion of secondary flow loss reached 47%, indicating the most significant impact.

6.
Cell Tissue Res ; 391(1): 1-17, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36380098

ABSTRACT

Spinal cord injury (SCI) is a very serious clinical traumatic illness with a very high disability rate. It not only causes serious functional disorders below the injured segment, but also causes unimaginable economic burden to social development. Exosomes are nano-sized cellular communication carriers that exist stably in almost all organisms and cell types. Because of their capacity to transport proteins, lipids, and nucleic acids, they affect various physiological and pathological functions of recipient cells and parental cells. Autophagy is a process that relies on the lysosomal pathway to degrade cytoplasmic proteins and organelles and involves a variety of pathophysiological processes. Exosomes and autophagy play critical roles in cellular homeostasis following spinal cord injury. Presently, the coordination mechanism of exosomes and autophagy has attracted much attention in the early efficacy of spinal cord injury. In this review, we discussed the interaction of autophagy and exosomes from the perspective of molecular mechanisms, which might provide novel insights for the early therapeutic application of spinal cord injury.


Subject(s)
Exosomes , Mesenchymal Stem Cells , Spinal Cord Injuries , Humans , Exosomes/metabolism , Spinal Cord Injuries/therapy , Autophagy , Neurons/metabolism , Mesenchymal Stem Cells/metabolism , Spinal Cord/pathology
7.
Electrophoresis ; 44(17-18): 1377-1404, 2023 09.
Article in English | MEDLINE | ID: mdl-37496295

ABSTRACT

The problem of pesticide residue contamination has attracted widespread attention and poses a risk to human health. The current traditional pesticide residue detection methods have difficulty meeting rapid and diverse field screening requirements. Microfluidic technology integrates functions from sample preparation to detection, showing great potential for quick and accurate high-throughput detection of pesticide residues. This paper reviews the latest research progress on microfluidic technology for pesticide residue detection. First, the commonly used microfluidic materials are summarized, including silicon, glass, paper, polydimethylsiloxane, and polymethyl methacrylate. We evaluated their advantages and disadvantages in pesticide residue detection applications. Second, the current pesticide residue detection technology based on microfluidics and its application to real samples are summarized. Finally, we discuss this technology's present challenges and future research directions. This study is expected to provide a reference for the future development of microfluidic technology for pesticide residue detection.


Subject(s)
Pesticide Residues , Humans , Pesticide Residues/analysis , Microfluidics , Drug Contamination
8.
BMC Cancer ; 23(1): 226, 2023 Mar 10.
Article in English | MEDLINE | ID: mdl-36894917

ABSTRACT

BACKGROUND: Cuproptosis is recently emerging as a hot spot in cancer research. However, its role in pancreatic adenocarcinoma (PAAD) has not yet been clarified. This study aimed to explore the prognostic and therapeutic implications of cuproptosis-related genes in PAAD. METHODS: Two hundred thirteen PAAD samples from the International Cancer Genome Consortium (ICGC) were split into training and validation sets in the ratio of 7:3. The Cox regression analyses generated a prognostic model using the ICGC cohort for training (n = 152) and validation (n = 61). The model was externally tested on the Gene Expression Omnibus (GEO) (n = 80) and The Cancer Genome Atlas (TCGA) datasets (n = 176). The clinical characteristics, molecular mechanisms, immune landscape, and treatment responses in model-defined subgroups were explored. The expression of an independent prognostic gene TSC22D2 was confirmed by public databases, real-time quantitative PCR (RT-qPCR), western blot (WB), and immunohistochemistry (IHC). RESULTS: A prognostic model was established based on three cuproptosis-related genes (TSC22D2, C6orf136, PRKDC). Patients were stratified into high- and low-risk groups using the risk score based on this model. PAAD patients in the high-risk group had a worse prognosis. The risk score was statistically significantly correlated with most clinicopathological characteristics. The risk score based on this model was an independent predictor of overall survival (OS) (HR = 10.7, p < 0.001), and was utilized to create a scoring nomogram with excellent prognostic value. High-risk patients had a higher TP53 mutation rate and a superior response to multiple targeted therapies and chemotherapeutic drugs, but might obtain fewer benefits from immunotherapy. Moreover, elevated TSC22D2 expression was discovered to be an independent prognostic predictor for OS (p < 0.001). Data from public databases and our own experiments showed that TSC22D2 expression was significantly higher in pancreatic cancer tissues/cells compared to normal tissues/cells. CONCLUSION: This novel model based on cuproptosis-related genes provided a robust biomarker for predicting the prognosis and treatment responses of PAAD. The potential roles and underlying mechanisms of TSC22D2 in PAAD need further explored.


Subject(s)
Adenocarcinoma , Apoptosis , Pancreatic Neoplasms , Humans , Adenocarcinoma/genetics , Adenocarcinoma/therapy , DNA-Binding Proteins , Immunotherapy , Pancreas , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/therapy , Prognosis , Transcription Factors , Copper , Pancreatic Neoplasms
9.
Environ Res ; 236(Pt 1): 116731, 2023 11 01.
Article in English | MEDLINE | ID: mdl-37517492

ABSTRACT

Biochar derived from soybean straw with AAEMs (alkali and alkaline earth metals) enrichment could efficiently remove heavy metals from contaminated water. In this study, the influences of pyrolysis temperature on the physicochemical property and adsorption performance of soybean straw biochar were investigated. The contributions of different adsorption mechanisms were analyzed quantitatively. The results show that the soybean straw biochar exhibits excellent Pb2+ adsorption performance (157.2-227.2 mg g-1), with an order of BC800 > BC400 > BC600 > BC700 > BC500. The mechanisms of metal ion exchange (37.49%-72.58%) and precipitation with minerals (22.38%-58.03%) mainly control the Pb2+ adsorption, whereas complexation with organic functional groups (OFGs) and cation-Cπ interaction make the less contribution. The order of cation exchange capacity (CEC) is BC400 > BC800 > BC700 > BC600 > BC500, showing a high correlation (0.965) with the contribution of metal ion exchange with AAEMs. Moreover, Ca exhibits the strongest exchange capacity. The contribution of precipitation is consistent with the variation of soluble CO32- content in biochar. These results suggest that soybean straw biochar rich in AAEMs is a prospective adsorbent for Pb2+ elimination.


Subject(s)
Charcoal , Lead , Adsorption , Charcoal/chemistry , Water , Cations
10.
Nano Lett ; 22(8): 3180-3186, 2022 Apr 27.
Article in English | MEDLINE | ID: mdl-35380445

ABSTRACT

The electronic structure and functionality of 2D materials is highly sensitive to structural morphology, not only opening the possibility for manipulating material properties but also making predictable and reproducible functionality challenging. Black phosphorus (BP), a corrugated orthorhombic 2D material, has in-plane optical absorption anisotropy critical for applications, such as directional photonics, plasmonics, and waveguides. Here, we use polarization-dependent photoemission electron microscopy to visualize the anisotropic optical absorption of BP with 54 nm spatial resolution. We find the edges of BP flakes have a shift in their optical polarization anisotropy from the flake interior due to the 1D confinement and symmetry reduction at flake edges that alter the electronic charge distributions and transition dipole moments of edge electronic states, confirmed with first-principles calculations. These results uncover previously hidden modification of the polarization-dependent absorbance at the edges of BP, highlighting the opportunity for selective excitation of edge states of 2D materials with polarized light.

11.
Analyst ; 147(13): 3065-3071, 2022 Jun 27.
Article in English | MEDLINE | ID: mdl-35671293

ABSTRACT

Fluorescence imaging in the near-infrared (NIR) window has great potential for clinical diagnosis and treatment because of its deep penetration and high contrast. Here, a NIR hemicyanine-based probe (CyP) was synthesized for selective detection and imaging of Hg2+ in living cells and animals. Using the rigid xanthene structure as the electron donor, trimethylindolenine as the electron acceptor and diphenylphosphinothioic chloride as the recognition element, the probe CyP could specifically respond to Hg2+ and transform into an activated donor-π-acceptor (D-π-A) motif with a NIR emission maximum at 710 nm. Cell and animal imaging experiments showed that the probe CyP could be activated by Hg2+ and had good concentration dependence in imaging. Meanwhile, animal imaging experiments showed that the activated CyP probe exhibited a higher tissue penetration depth and spatiotemporal resolution. Thus, the probe CyP could be a useful tool for monitoring and visually evaluating Hg2+ in living systems.


Subject(s)
Fluorescent Dyes , Mercury , Animals , Carbocyanines/chemistry , Fluorescent Dyes/chemistry , Fluorescent Dyes/toxicity , Optical Imaging
12.
J Transl Med ; 19(1): 433, 2021 10 17.
Article in English | MEDLINE | ID: mdl-34657620

ABSTRACT

BACKGROUND: Colorectal carcinoma (CRC) harboring oncogenic fusions has been reported to be highly enriched in mismatch repair deficient (dMMR) tumors with MLH1 hypermethylation (MLH1me+) and wild-type BRAF and RAS. In this study, dMMR CRCs were screened for oncogene fusions using sequential DNA and RNA next generation sequencing (NGS). RESULTS: Comprehensive analysis of fusion variants, genetic profiles and clinicopathological features in fusion-positive dMMR CRCs was performed. Among 193 consecutive dMMR CRCs, 39 cases were identified as MLH1me+ BRAF/RAS wild-type. Eighteen fusion-positive cases were detected by DNA NGS, all of which were MLH1me+ and BRAF/RAS wild-type. RNA NGS was sequentially conducted in the remaining 21 MLH1me+ BRAF/RAS wild-type cases lacking oncogenic fusions by DNA NGS, and revealed four additional fusions, increasing the proportion of fusion-positive tumors from 46% (18/39) to 56% (22/39) in MLH1me+ BRAF/RAS wild-type dMMR cases. All 22 fusions were found to involve RTK-RAS pathway. Most fusions affected targetable receptor tyrosine kinases, including NTRK1(9/22, 41%), NTRK3(5/22, 23%), ALK(3/22, 14%), RET(2/22, 9%) and MET(1/22, 5%), whilst only two fusions affected mitogen-activated protein kinase cascade components BRAF and MAPK1, respectively. RNF43 was identified as the most frequently mutated genes, followed by APC, TGFBR2, ATM, BRCA2 and FBXW7. The vast majority (19/22, 86%) displayed alterations in key WNT pathway components, whereas none harbored additional mutations in RTK-RAS pathway. In addition, fusion-positive tumors were typically diagnosed in elder patients and predominantly right-sided, and showed a significantly higher preponderance of hepatic flexure localization (P < 0.001) and poor differentiation (P = 0.019), compared to fusion-negative MLH1me+ CRCs. CONCLUSIONS: We proved that sequential DNA and RNA NGS was highly effective for fusion detection in dMMR CRCs, and proposed an optimized practical fusion screening strategy. We further revealed that dMMR CRCs harboring oncogenic fusion was a genetically and clinicopathologically distinctive subgroup, and justified more precise molecular subtyping for personalized therapy.


Subject(s)
Colorectal Neoplasms , Oncogene Fusion , Aged , Colorectal Neoplasms/genetics , DNA , DNA Mismatch Repair/genetics , High-Throughput Nucleotide Sequencing , Humans , MutL Protein Homolog 1/genetics , Mutation/genetics , Proto-Oncogene Proteins B-raf/genetics , RNA , ras Proteins
13.
Mod Pathol ; 33(12): 2591-2601, 2020 12.
Article in English | MEDLINE | ID: mdl-32620917

ABSTRACT

Colorectal carcinoma (CRC) with deficient mismatch repair (dMMR) is an etiologically heterogeneous molecular entity. We investigated the genetic profile, focusing on key signaling pathways and molecular diversity of dMMR CRCs. In this study, next-generation sequencing was applied to 156 consecutive dMMR CRCs and 225 randomly selected proficient MMR (pMMR) CRCs diagnosed between July 2015 and December 2019 at Peking Union Medical College Hospital. Genetic alterations and MLH1 promoter hypermethylation (MLH1me+) were analyzed. Among the most frequently mutated genes, RNF43, ARID1A, PIK3CA, ATM, and BRCA2 mutants were enriched in dMMR CRCs, whereas APC and TP53 mutations were enriched in pMMR CRCs. In dMMR group, RNF43, APC, ARID1A, and BRCA2 mutations were largely microsatellite instability events. WNT pathway was commonly altered regardless of MMR status. Compared to pMMR CRCs, dMMR CRCs had remarkably more prevalent PI3K, RTK-RAS, TGFß, and DNA damage repair pathway alterations and more multiple mutations in WNT and PI3K pathways. Within dMMR tumors, mutual exclusivity occurred between CTNNB1 mutation and APC or RNF43 mutation, while coexistence existed between BRAF and RNF43 mutation, as well as RAS and APC mutation. MLH1me+ dMMR CRCs had significantly more frequent RNF43 mutations but less frequent KRAS, APC, and CTNNB1 mutations comparing to MLH1-unmethylated dMMR CRCs. RNF43/BRAF comutations were detected in MLH1me+ dMMR CRCs, whereas RAS/APC comutations were largely detected in Lynch syndrome-associated cases. RNF43 mutation was independently associated with MLH1me+ rather than BRAF mutations. dMMR CRCs bearing receptor tyrosine kinase fusion demonstrated no additional RTK-RAS mutations, significantly fewer PI3K alterations and more TGFBR2 mutations than other dMMR tumors. Our study revealed that dMMR CRCs had distinctive gene mutation spectra and signaling pathway interaction patterns compared to proficient mismatch repair (pMMR) CRCs, and molecular heterogeneity was evident for these divergent oncogenic pathways. These findings justify the use of individualized therapy targeted to dMMR CRC subgroups.


Subject(s)
Biomarkers, Tumor/genetics , Colorectal Neoplasms/genetics , DNA Mismatch Repair , DNA Mutational Analysis , Genetic Heterogeneity , High-Throughput Nucleotide Sequencing , Mutation , Signal Transduction/genetics , Clinical Decision-Making , Colorectal Neoplasms/pathology , Colorectal Neoplasms/therapy , DNA Methylation , Gene Fusion , Genetic Predisposition to Disease , Humans , MutL Protein Homolog 1/genetics , Phenotype , Precision Medicine , Predictive Value of Tests , Promoter Regions, Genetic , Retrospective Studies
14.
Am J Otolaryngol ; 41(4): 102538, 2020.
Article in English | MEDLINE | ID: mdl-32451288

ABSTRACT

PURPOSE: This study aimed to evaluate the efficacy and adherence of sublingual immunotherapy (SLIT) for house dust mite (HDM)-induced allergic rhinitis (AR) patients over 60 years old. MATERIALS AND METHODS: Eighty-six AR patients aged 60-75 years old were randomly divided in the control and treatment group as 1:1 ratio. The control group was treated with standard pharmacotherapy while the treatment group was treated with SLIT plus pharmacotherapy on demand. Patients adherence, combined symptom and medication score (CSMS), visual analog scale (VAS), and presence of adverse events were evaluated in the baseline and after 6-months, 12-months and 24-months treatment. RESULTS: Twenty-five (58.1%) subjects in the treatment group and 20 (46.5%) subjects in the control group completed the study (P > 0.05). The major reasons for premature cessation were out of touch and relieved symptoms. At the same time, CSMS and VAS of the patients over 60 years old in both groups significantly decreased from baseline to any post-baseline time point (all P < 0.05). The comparison of CSMS and VAS between the two groups revealed statistically significant differences in favor of the SLIT group at month 24 (P < 0.05), whereas no differences at month 6 and month 12 (all P > 0.05). CONCLUSION: 41.9% of the patients dropped out within 2 years of SLIT treatment and the major reasons for premature cessation were out of touch and relieved symptoms. This study suggested that SLIT plus pharmacotherapy provided a greater clinical benefit than pharmacotherapy alone at two years.


Subject(s)
Medication Adherence , Patient Compliance , Patient Dropouts , Pyroglyphidae , Rhinitis, Allergic , Sublingual Immunotherapy , Aged , Animals , Female , Humans , Male , Middle Aged , Administration, Sublingual , Age Factors , Combined Modality Therapy , Follow-Up Studies , Pyroglyphidae/pathogenicity , Rhinitis, Allergic/drug therapy , Rhinitis, Allergic/etiology , Rhinitis, Allergic/therapy , Sublingual Immunotherapy/adverse effects , Sublingual Immunotherapy/methods , Time Factors , Treatment Outcome
15.
Acta Pharmacol Sin ; 38(10): 1340-1352, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28649126

ABSTRACT

The root of Polygonum multiflorum Thunb (PM) has been used in China to treat a variety of diseases, such as constipation, early graying of the hair and hyperlipemia. Recent evidence shows that PM causes idiosyncratic drug-induced liver injury (IDILI) in humans. In this study, we investigated the molecular basis of PM-induced liver injury in a rat model of IDILI based on a non-hepatotoxic dose of LPS. SD rats were orally administered 3 potentially hepatotoxic compounds of PM: cis-stilbene glucoside (cis-SG, 50 mg/kg), trans-SG (50 mg/kg) or emodin (5 mg/kg), followed by injection of LPS (2.8 mg/kg, iv). Serum and liver histology were evaluated 7 h after LPS injection. Among the 3 compounds tested, cis-SG, but not emodin or trans-SG, induced severe liver injury in rats when combined with LPS. The levels of AST and ALT in plasma and inflammatory cytokines in both plasma and liver tissues were markedly elevated. The liver tissues showed increased injury, hepatocyte apoptosis, and macrophage infiltration, and decreased cell proliferation. Microarray analysis revealed a negative correlation between peroxisome proliferator-activated receptor-γ (PPAR-γ) and LPS/cis-SG-induced liver injury. Immunohistochemical staining and RT-PCR results further confirmed that cis-SG significantly inhibited activation of the PPAR-γ pathway in the liver tissues of LPS/cis-SG-treated rats. Pre-treatment with a PPAR-γ agonist pioglitazone (500 g/kg, ig) reversed LPS/cis-SG-induced liver injury, which was associated with inhibiting the nuclear factor kappa B (NF-κB) pathway. These data demonstrate that cis-stilbene glucoside induces immunological idiosyncratic hepatotoxicity through suppressing PPAR-γ in a rat model of IDILI.


Subject(s)
Chemical and Drug Induced Liver Injury/etiology , Fallopia multiflora/chemistry , Glucosides/toxicity , Stilbenes/toxicity , Animals , Chemical and Drug Induced Liver Injury/physiopathology , Emodin/pharmacology , Glucosides/chemistry , Glucosides/isolation & purification , Lipopolysaccharides/administration & dosage , Male , Microarray Analysis , NF-kappa B/metabolism , PPAR gamma/metabolism , Pioglitazone , Plant Roots , Rats , Rats, Sprague-Dawley , Severity of Illness Index , Stereoisomerism , Stilbenes/chemistry , Stilbenes/isolation & purification , Thiazolidinediones/pharmacology
16.
Phys Chem Chem Phys ; 18(22): 14904-10, 2016 06 01.
Article in English | MEDLINE | ID: mdl-27189744

ABSTRACT

Carbon nitrides (CN) have been widely used in photocatalytic applications. However, the charge carrier kinetics of CN after light excitation remains unclear. Herein, we prepared a stable and transparent CN colloid in an aqueous tetraethylammonium hydroxide solution and investigated its carrier kinetics using both femtosecond transient absorption and picosecond time-resolved fluorescence spectroscopy. We found that a new and positive absorption band appears in the femtosecond transient absorption spectrum of the CN colloid, which could be attributed to the absorption of the photogenerated electron/hole pairs (or the electronic excited state) of the CN colloid after light excitation. Moreover, we found that the charge carrier kinetics obtained from the femtosecond transient absorption measurements is dramatically different from that obtained from the picosecond time-resolved fluorescence measurements, indicating that the photophysical process of the CN colloid after light excitation is complicated. With the results obtained from both the femtosecond transient absorption and picosecond time-resolved fluorescence measurements, we proposed a schematic to understand the photophysics and charge carrier kinetics of the CN colloid. We believe that the current study is also significant for researchers to understand the photophysics and charge carrier kinetics of bulk CN.

18.
J Sep Sci ; 39(22): 4281-4289, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27624993

ABSTRACT

Many foods and herbs are experientially classified into different commodity grades in commercial circulation. Regarding the hypertoxic herb aconite, large samples are considered to be of better quality. However, this experiential classification lacks a scientific basis. In this study, we focused on the quality diversity among different grades and studied it using the minimum lethal dose assay and a novel ultra high performance liquid chromatography coupled with time-of-flight mass spectrometry method. Toxicity assay result suggested grade I aconite had the lowest toxicity (p < 0.05). Using this method with partial least squares-discriminant analysis, we discovered nine chemomarkers, including neoline, songorine, fuziline, mesaconitine, talatizidine, dexyaconitine, talatisamine, hypaconitine, and fuzitine. Considering their toxicity and activity, we found the levels of toxic ingredients hypaconitine, dexyaconitine, and mesaconitine in grade I were lower than those in grade II (p < 0.01), while the levels of efficacy ingredients songorine, talatisamine, and neoline were the highest in grade I (p < 0.01). Further study demonstrated that the quality variation was associated with plant tissue development and toxic ingredient distribution law. Our results provide scientific evidence for the experiential quality evaluation of aconite, and it will be of great utility for other foods and herbs.


Subject(s)
Aconitum/chemistry , Drugs, Chinese Herbal/analysis , Chromatography, High Pressure Liquid , Mass Spectrometry , Quality Control
19.
J Sep Sci ; 39(22): NA, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27886464

ABSTRACT

J. Sep. Sci. 2016, 39, 4281-4289 DOI: 10.1002/jssc.201600567 Aconite, called tiger and wolf drug, is known in Traditional Chinese Medicine for its strong cardiac effect. In the past, the toxins extracted from aconite were used as arrow poisons to kill animals, hence the name "wolf's bane." To a certain extent, the wolf represents the medicinal characteristics of aconite: fierce, wild and intractable. The cover picture shows, besides the wolf head as the main element, a flow chart of our study and summarizes the main topics of our article.

20.
Yao Xue Xue Bao ; 51(1): 116-21, 2016 Jan.
Article in Zh | MEDLINE | ID: mdl-27405172

ABSTRACT

Decoction is one of the most commonly used dosage forms of traditional Chinese medicine. The stability of chemical constituents in decoction is closely related to the clinical efficacy and safety. There were few reports about the influence of metal ions in the stability of chemical constituents in traditional Chinese medicine. However, there is no evidence that metal ions in decoction water need to be controlled. In this study, 2,3,5,4'-tetrahydroxy stilbene-2-O-ß-D-glucoside (THSG), one of the main constituents in Polygoni Multiflori Radix was studied. Ordinary tap water, deionized water, and water containing different metal ions were used to investigate and compare the influence on THSG. The results showed that after storage in a dark place at the room temperature for 10 days, the degradation of THSG was 7% in deionized water, while undetectable in tap water. The content of THSG could be decreased by different kinds of metal ions, and the effect was concentration-dependent. Moreover, Fe3+ and Fe2+ showed the greatest influence at the same concentration; and our study has shown that THSG decreased more than 98% in Fe and Fe2+ solutions at 500 ppm concentration. In the same time we found out p-hydroxybenzaldehyde (molecular weight: 122.036 7) and 2,3,5-trihydroxybenzaldehyde-2-O-glycoside (molecular weight: 316.079 4) were the main degradation products of THSG in tap water and water containing Cu2+, Ca2+, Zn2+, Mg2+ and Al3+. The product of THSG dimer with a water molecule was found in water containing Fe3+ and Fe2+. The above results showed that the metal ions in water could significantly influence the stability of THSG in water, indicating that the clinical efficacy and safety of decoction would be affected if the metal ions in water were not under control. It's suggested that deionized water should be used in the preparation of decoction containing Polygoni Multiflori Radix in the clinic to avoid degradation of THSG. Meanwhile, decoction prepared by tap water should be taken by patients in a short time. Our investigation provides important information and reference about the influence of metal ions on the stability of decoctions in other traditional Chinese medicine that have unstable groups such as hydroxyls and unsaturated bonds, etc.


Subject(s)
Drugs, Chinese Herbal/chemistry , Glucosides/chemistry , Ions/chemistry , Metals/chemistry , Polygonaceae/chemistry , Stilbenes/chemistry , Plant Roots/chemistry
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