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1.
J Gene Med ; 25(4): e3478, 2023 04.
Article in English | MEDLINE | ID: mdl-36740786

ABSTRACT

BACKGROUND: Non-small-cell lung cancer (NSCLC) is a common cancer. Chemotherapeutic drug resistance limits the therapeutic effect of NSCLC and leads to a poor prognosis. As a result, new specific targets may be better identified by studying the mechanism of drug resistance to cisplatin in NSCLC. METHODS: In the present study, we performed a quantitative real-time polymerase chain reaction and western blotting to detect mRNA and protein levels. The proliferation of cells was analyzed by a Cell Counting Kit-8 and colony formation assays. Cell invasion was measured via the Transwell assay. A scratch assay was performed to measure cell migration in cisplatin (DDP)-resistant NSCLC cells. Apoptosis of cells was examined using flow cytometry. RESULTS: We found that circANKRD28 was notably decreased in NSCLC. The results showed that circANKRD28 expression was not affected, and its half-life was more than 12 h. Functional experiments revealed that circANKRD28 overexpression inhibited DDP resistance in NSCLC cells in vitro. Mechanistic findings demonstrated that circANKRD28 regulated tumor cell progression and DDP sensitivity through the miR-221-3p/SOCS3 axis. CONCLUSIONS: The present study revealed the regulatory effects and molecular mechanism of circANKRD28 on the development and cisplatin resistance in NSCLC, which may provide experimental basis and theoretical support to identify new targets for therapy of DDP resistance in NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , MicroRNAs , RNA, Circular , Humans , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Cell Proliferation/genetics , Cisplatin/pharmacology , Cisplatin/therapeutic use , Drug Resistance, Neoplasm/genetics , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , MicroRNAs/genetics , MicroRNAs/metabolism , Suppressor of Cytokine Signaling 3 Protein/genetics , Suppressor of Cytokine Signaling 3 Protein/metabolism , RNA, Circular/genetics
2.
BMC Gastroenterol ; 23(1): 440, 2023 Dec 14.
Article in English | MEDLINE | ID: mdl-38097952

ABSTRACT

BACKGROUND: Type 1 gastric neuroendocrine tumors (NETs) are relatively rare to the extent that some physicians have little experience in diagnosing and treating them. The purpose of this study was to increase the understanding of the disease by analyzing and summarizing the management and prognoses of patients with type 1 gastric NETs at our center. METHODS: The data of 229 patients (59.4% female) with type 1 gastric NETs who were treated at our center during 2011-2022 were retrospectively analyzed. RESULTS: The average patient age was 50.5 ± 10.8 years. Multiple tumors affected 72.5% of the patients; 66.4% of the tumors were < 1 cm, 69.4% were NET G1, and 2.2% were stage III-IV. A total of 76.9% of the patients had received endoscopic management, 60.7% had received traditional Chinese medicine treatment, 10.5% received somatostatin analogues treatment, and 6.6% underwent surgical resection. Seventy patients (41.2%) experienced the first recurrence after a median follow-up of 31 months (range: 2-122 months), and the median recurrence-free time was 43 months. The 1-, 2-, and 3-year cumulative recurrence-free survival rates were 71.8%, 56.8%, and 50.3%, respectively. During a median follow-up of 39 months (range: 2-132 months), one patient had bilateral pulmonary metastasis, and no disease-related deaths were observed. CONCLUSION: Type 1 gastric NETs have a high recurrence rate and a long disease course, underscoring the importance of long-term and comprehensive management.


Subject(s)
Neuroendocrine Tumors , Stomach Neoplasms , Humans , Female , Adult , Middle Aged , Male , Neuroendocrine Tumors/diagnosis , Neuroendocrine Tumors/therapy , Neuroendocrine Tumors/pathology , Retrospective Studies , Prognosis , Stomach Neoplasms/diagnosis , Stomach Neoplasms/therapy
3.
Mikrochim Acta ; 190(10): 395, 2023 Sep 16.
Article in English | MEDLINE | ID: mdl-37715796

ABSTRACT

In order to improve the extraction ability of carbon fibers (CFs) for microextraction of polycyclic aromatic hydrocarbons (PAHs), biochar nanospheres derived from glucose were in-situ grown onto the surface of CFs via hydrothermal synthesis. The surface morphology and elemental composition of biochar nanospheres-CFs were investigated by scanning electron microscopy and X-ray photoelectron spectroscopy. Thereafter, the biochar nanosphere-CFs were pulled into the polyetheretherketone tube for solid-phase microextraction, and the tube was combined with high-performance liquid chromatography-diode array detector to online detect PAHs. With the help of π-stacking, hydrophobic, and hydrophilic effect of biochar nanospheres, the extraction efficiency of CFs was greatly enhanced (enrichment factor increased by 293% compared with  the original). The conditions affecting the analytical performance (sampling volume, sampling rate, methanol content, and desorption time) were investigated. Under the optimal conditions, an online analytical method for microextraction and determination of several PAHs was developed, and satisfactory results were achieved. The limits of detection were 0.003-0.010 ng mL-1 owing to high enrichment effect (2973-3600), linearity ranged from  0.010-15.0 ng mL-1, and relative standard deviations were 0.4%-1.6% (intra-day) and 2.4%-4.4% (inter-day), respectively. The method was applied to analyze environmental water samples (rain water, snow water, and river water), and spiked recoveries within 80.0%-119% were obtained.

4.
Mikrochim Acta ; 190(11): 438, 2023 10 16.
Article in English | MEDLINE | ID: mdl-37843728

ABSTRACT

An aptamer sensor has been developed utilizing a dual-mode and stimuli-responsive strategy for quantitative detection of AßO (amyloid-beta oligomers) through simultaneous electrochemical and fluorescence detection. To achieve this, we employed UIO-66-NH2 as a carrier container to load MB (Methylene Blue), and Fe3O4 MNPs (iron oxide magnetic nanoparticles) with aptamer (ssDNA-Fe3O4 MNPs) fixed on their surface for biological gating. The ssDNA-Fe3O4 MNPs were immobilized onto the surface of UIO-66-NH2 through hydrogen bonding between the aptamer and the -NH2 group on the surface of UIO-66-NH2, thereby encapsulating MB and forming ssDNA-Fe3O4@MB@UIO-66-NH2. During the detection of AßO, the aptamer selectively reacted with AßO to form the AßO-ssDNA-Fe3O4 complex, leading to its detachment from the surface of UIO-66-NH2. This detachment facilitated the release of MB, enabling its electrochemical detection. Simultaneously, the AßO-ssDNA-Fe3O4 complex was efficiently collected and separated using a magnet after leaving the container's surface. Furthermore, the addition of NaOH facilitated the disconnection of biotin modifications at the 3' end of the aptamer from the avidin modifications on the Fe3O4 MNPs. Consequently, the aptamer detached from the surface of Fe3O4 MNPs, resulting in the restoration of fluorescence intensity of FAM (fluorescein-5'-carboxamidite) modified at its 5' end for fluorescence detection. The dual-mode sensor exhibited significantly enhanced differential pulse voltammetry signals and fluorescence intensity compared to those in the absence of AßO. The sensor demonstrated a wide detection range of 10 fM to 10 µM, with a detection limit of 3.4 fM. It displayed excellent performance in detecting actual samples and holds promising prospects for early diagnosis of Alzheimer's disease.


Subject(s)
Alzheimer Disease , Aptamers, Nucleotide , Humans , Amyloid beta-Peptides , Fluorescence , Alzheimer Disease/diagnosis
5.
Mikrochim Acta ; 190(6): 206, 2023 05 10.
Article in English | MEDLINE | ID: mdl-37162685

ABSTRACT

Using gold (Au) nanoparticle decorated Ti3C2Tx (Ti3C2Tx-Au) nanocomposites, a highly sensitive electrochemical aptasensor for the effective detection of chloramphenicol has been developed. As a two-dimensional layered material, the prepared composite not only provides high surface area, good conductivity, and thermal stability but also substantial binding sites for aptamers with high sensitivity and selectivity for the accurate determination of chloramphenicol. Interestingly, the conductivity and active sites were enhanced by freeze-drying Ti3C2Tx and in situ formation of Ti3C2Tx-Au nanocomposite. The fabricated aptasensor exhibited a very low detection limit (S/N ≥ 3) of 13.18 fg mL-1 with a linear range of 1 ~ 700 pg mL-1 and correlation coefficient of 0.9992. The fabricated aptasensor demonstrated an excellent reproducibility, repeatability, long-term stability, and high selectivity toward chloramphenicol. Further, the aptasensor was applied to real milk samples, and the recoveries were ranged from 98.93 to 101.93%.


Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , Metal Nanoparticles , Nanocomposites , Chloramphenicol , Gold/chemistry , Metal Nanoparticles/chemistry , Reproducibility of Results , Aptamers, Nucleotide/chemistry , Biosensing Techniques/methods , Electrochemical Techniques/methods , Titanium , Nanocomposites/chemistry
6.
Mikrochim Acta ; 189(9): 332, 2022 08 15.
Article in English | MEDLINE | ID: mdl-35971003

ABSTRACT

A strand displacement-based "signal-off" electrochemical aptasensor is reported for the detection of Mucin 1 (MUC 1) based on a high original signal. Different from the conventional "signal-off" electrochemical biosensors where electrochemical substances are dispersed in electrolyte solution, here the current signal was generated by the complementary probe (CP) associated with ferrocene (Fc) labeled aptamer (Apt.-Fc). Because Apt.-Fc and MUC 1 have a higher affinity, Apt.-Fc dissociates from CP in the presence of MUC 1, resulting in a reduction of detection current signal generated by oxidation of labeled Fc. In this system, high detection signal is necessary to improve the sensor's performance. For this aim, a strategy is proposed for changing the modalities of electron transport and the quantity of Apt.-Fc introduced by simply tuning the sequence constitution of CP. As expected, a high detection current signal was obtained after selecting CP(Apt.-Fc)-TTT as the optimal CP. The aptasensor was then employed to detect MUC 1, and satisfactory detection results with a low detection limit (LOD) of 0.087 pM (S/N = 3), good specificity, good stability, and feasibility of detection of MUC 1 in artificial serum (recovery of 92-101%, RSD of 1.36-5.23%) were obtained.


Subject(s)
Aptamers, Nucleotide , Mucin-1 , Aptamers, Nucleotide/chemistry , Electrochemical Techniques/methods , Limit of Detection , Metallocenes/chemistry
7.
Anal Bioanal Chem ; 413(16): 4353-4362, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34013401

ABSTRACT

A novel electrochemical DNA sensor was designed to detect Helicobacter pylori based on accordion-like Ti3C2Tx. Here the multilayer Ti3C2Tx obtained by DMSO delamination was used to modify the glass carbon electrode, with a large specific surface area and excellent conductivity. Au nanoparticles were supported on the modified electrode and worked as an effective carrier to fix the capture probe (cpDNA) with sulfhydryl group through the firm binding of Au-S bond. Such an accordion-like Ti3C2Tx structure provides an ultrahigh electroactive surface area and ample binding sites for accommodating Au nanoparticles, which is advantageous for the signal amplification during the detection. And further, the sandwich structure formed by hybridizing cpDNA with target DNA sequence (tDNA) and rpDNA (rpDNA is a strand of DNA that can be base-paired with the tested tDNA) increases greatly the current signal and enhances the sensitivity of the electrochemical DNA sensor. Under optimal conditions, the developed electrochemical DNA sensor showed a wide linear range from 10-11 to 10-14 M and a low detection limit of 1.6 × 10-16 M and exhibited good sensitivity, reproducibility, and stability. A novel electrochemical DNA sensor with simple sandwich structure was designed to detect H. pylori based on accordion-like Ti3C2Tx.


Subject(s)
DNA, Bacterial/analysis , Electrochemical Techniques/methods , Helicobacter pylori/isolation & purification , Metal Nanoparticles/chemistry , Titanium/chemistry , Animals , Biosensing Techniques , Electrodes , Gold/chemistry , Helicobacter Infections/blood , Helicobacter Infections/microbiology , Humans , Limit of Detection , Milk/microbiology , Nucleic Acid Hybridization/methods
8.
Anal Bioanal Chem ; 413(19): 4847-4854, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34115147

ABSTRACT

An interference-free photoelectrochemical (PEC) immunoassay was developed for cardiac troponin I (cTnI) detection. Covalent linkage of cTnI antibody to carboxymethylated (CM-) dextran pre-immobilized onto a gold nanoparticles (AuNPs)-modified TiO2 nanotube array (NTA) affords five consecutive analyte captures with surface regenerations in between. Changes in the photocurrents at this photoanode before and after cTnI captures can be well fitted with the Langmuir isotherm from 0.220 pM to 2.20 nM cTnI. Owing to the inherently high sensitivity of the PEC detection, the detection limit (2.20 pg/mL) is lower than the range attainable with the enzyme-linked immunosorbent assay (ELISA) (6.00-40.0 pg/mL). Furthermore, CM-dextran prevents species in complex biological matrices from nonspecifically adsorbing onto the sensor surface, a feature not attainable with uncoated semiconductor electrodes or those coated with non-hydrogel-based chemical modifiers. The excellent anti-fouling property of dextran hydrogel allowed us to validate the accuracy of our regenerable sensors through a comparison of PEC immunoassays of patient sera to those of ELISA.


Subject(s)
Dextrans/chemistry , Electrochemical Techniques , Gold/chemistry , Immunoassay/methods , Photochemical Processes , Titanium/chemistry , Biomarkers , Electrodes , Humans , Nanotubes/chemistry , Troponin I/chemistry
9.
Exp Cell Res ; 390(1): 111939, 2020 05 01.
Article in English | MEDLINE | ID: mdl-32142853

ABSTRACT

MiR-328-3p has been reported to be downregulated and serve as a tumor suppressor in several cancers. Previous studies only have reported the downregulation of miR-328-3p in CRC. However, the roles of miR-328-3p in CRC growth and metastasis were unknown. In this study, we demonstrated that miR-328-3p overexpression inhibited cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT). The PI3K/Akt signaling pathway was also inactivated by miR-328-3p overexpression. MiR-328-3p knockdown showed the opposite effects. In addition, we confirmed that miR-328-3p directly bound to 3'UTR of Girdin and negatively regulated its expression. Girdin knockdown or treatment with PI3K inhibitor LY294002 blocked the effects of miR-328-3p inhibitor on cell proliferation, metastasis, and the PI3K/Akt signaling pathway. Moreover, pre-miR-328 decreased numbers of liver metastatic nodules, and reduced the levels of p-Akt, p-Girdin, and Girdin in metastatic tissues in liver. In conclusion, miR-328-3p may inhibit proliferation and metastasis of CRC cells by targeting Girdin and inactivating the PI3K/Akt signaling pathway. MiR-328-3p may be a novel target in cancer therapy.


Subject(s)
Cell Proliferation , Colorectal Neoplasms/genetics , MicroRNAs/metabolism , Microfilament Proteins/genetics , Vesicular Transport Proteins/genetics , Animals , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , Epithelial-Mesenchymal Transition , HCT116 Cells , Humans , Male , Mice , Mice, Inbred BALB C , Mice, Nude , MicroRNAs/genetics , Microfilament Proteins/metabolism , Neoplasm Metastasis , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Vesicular Transport Proteins/metabolism
10.
Molecules ; 26(14)2021 Jul 13.
Article in English | MEDLINE | ID: mdl-34299527

ABSTRACT

A label free electrochemical sensor based on pure titanium oxide and manganese (Mn)-doped titanium oxide (TiO2) nanoparticles are fabricated and characterized for the sensitive detection of myoglobin (Mb) levels to analyze the cardiovascular infarction. Pristine and Mn-doped TiO2 nanoparticles were synthesized via the sol-gel method and characterized in order to understand their structure, morphologies, composition and optical properties. The structural properties revealed that the pure- and doped-TiO2 nanoparticles possess different TiO2 planes. FTIR studies confirm the formation of metal oxide nanoparticles by exhibiting a well-defined peak in the range of 600-650 cm-1. The values of the optical band gap, estimated from UV-Vis spectroscopy, are decreased for the Mn-doped TiO2 nanoparticles. UV-Vis spectra in the presence of myoglobin (Mb) indicated interaction between the TiO2 nanoparticles and myoglobin. The SPE electrodes were then fabricated by printing powder film over the working electrode and tested for label-free electrochemical detection of myoglobin (Mb) in the concentration range of 0-15 nM Mb. The fabricated electrochemical sensor exhibited a high sensitivity of 100.40 µA-cm-2/nM with a lowest detection limit of 0.013 nM (0.22 ng/mL) and a response time of ≤10 ms for sample S3. An interference study with cyt-c and Human Serum Albumin (HSA) of the sensors show the selective response towards Mb in 1:1 mixture.


Subject(s)
Manganese/chemistry , Myoglobin/analysis , Nanoparticles/chemistry , Titanium/chemistry , Biomarkers/analysis , Electrochemical Techniques , Humans , Myocardial Infarction/diagnosis
11.
Anal Bioanal Chem ; 412(30): 8443-8450, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33025034

ABSTRACT

We developed a dual-modal colorimetric and photothermal assay for glutathione (GSH) using MnO2 nanosheets prepared with environmentally friendly materials. The nanosheets were synthesized by using ascorbic acid present abundantly in lemon and orange juices to reduce KMnO4. The as-prepared MnO2 nanosheets display oxidase-like activity and can catalyze the oxidation reaction of 3,3',5,5'-tetramethylbenzidine (TMB), yielding a blue oxidative product (oxTMB) that exhibits a UV-Vis absorption peak at 652 nm. In the presence of GSH, the MnO2 nanosheets are reduced and decomposed, resulting in a decrease in the peak intensity. The colorimetric assay offers a wide dynamic range (0.1-100 µM) and a detection limit of 100 nM. The MnO2 nanosheets are also efficient in converting photoenergy to thermal energy, with a photothermal conversion efficiency of 23.3%. The temperature change, after near-infrared (NIR) irradiation at 808 nm, can be easily measured by an inexpensive pen-type thermometer. This effect can also be used for GSH quantification and expands the GSH concentration detection to the range from 6.0 to 200 µM. The viability of our dual-modal assay for clinical applications was demonstrated with successful analyses of GSH in human serum samples. Graphical abstract.


Subject(s)
Colorimetry/methods , Glutathione/analysis , Manganese Compounds/chemistry , Nanostructures/chemistry , Oxides/chemistry , Glutathione/blood , Humans , Limit of Detection , Oxidation-Reduction , Spectrum Analysis/methods
12.
J Sep Sci ; 43(3): 622-630, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31675467

ABSTRACT

Triazine-based organic polymers@SiO2 nanospheres were prepared and applied as an extraction coating onto stainless steel wires and the wires were filled into polyetheretherketone tube for in-tube solid-phase microextraction. Taking polycyclic aromatic hydrocarbons as targets, main factors affecting extraction performance of the tube were investigated through coupling to high performance liquid chromatography. Under the optimum conditions, an online analytical method for polycyclic aromatic hydrocarbons was established with large linear ranges (0.010-20 µg/L), low limits of detection (0.003-0.010 µg/L), high enrichment factors (533-2954), and good repeatability (relative standard deviations <1.7% for intraday test, <5.0% for interday test). The analysis method was successfully applied to the detection of trace targets in real water samples and the relative recoveries ranged from 82.9 to 119.9%, which demonstrated the applicability of extraction tube in sample preparation.

13.
J Sep Sci ; 43(23): 4364-4373, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32979006

ABSTRACT

A facile method was introduced for preparing a biocharcoal aerogel, which was derived from pomelo peel as the only raw material. The inner spongy layer of pomelo peel was freeze-dried for maintaining three-dimensional structure and then carbonized under high temperature and oxygen-limited conditions. The morphological structure and graphitization degree of biocharcoal aerogel were characterized using a scanning electron microscope and Raman spectrum. After sifting and grinding, the biocharcoal aerogel as an adsorbent was coated onto the surface of stainless steel wires. Through placing the wires into a polyetheretherketone tube, the in-tube solid-phase microextraction device was obtained. Coupled with high-performance liquid chromatography, it exhibited good extraction performance for polycyclic aromatic hydrocarbons, then an online analytical method was established with low limits of detection (0.005-0.050 ng/mL), wide linear ranges (0.017-15 ng/mL) with superior correlation coefficients higher than 0.9990, high enrichment factors (1128-3425), and acceptable intra- and inter-day repeatabilities (relative standard deviations ≤ 6.7%, n = 3). The method was applied to detect polycyclic aromatic hydrocarbons in bottled water samples, environmental water samples, and soft drinks with satisfactory recoveries (83.3-120.9%). This research not only developed a new carbon aerogel but also evaluated its adsorption performance in sample preparation.


Subject(s)
Charcoal/chemistry , Polycyclic Aromatic Hydrocarbons/analysis , Solid Phase Microextraction , Water Pollutants, Chemical/chemistry , Adsorption , Gels/chemistry , Particle Size , Surface Properties
14.
Analyst ; 144(19): 5866-5874, 2019 Oct 07.
Article in English | MEDLINE | ID: mdl-31482879

ABSTRACT

To enhance the sensitivity of an aptasensor, a novel strategy was designed to develop an electrochemical aptasensor based on poly(3,4-ethylenedioxy thiophene)-gold nanoflower (PEDOT-AuNF) composites supported on a three-dimensional graphene oxide sponge (GOS). GOS with a three-dimensional sponge-like porous structure, exhibiting excellent electrical conductivity and a large surface area, provided the first amplification of the electrochemical signal for ochratoxin A (OTA) detection. PEDOT-AuNFs, synthesized by an ionic liquid-assisted one-pot method, presented a peculiar hierarchical flower-like structure, a high electroactive surface area, and more binding sites for immobilizing the aptamer molecules by the Au-S bonds. When PEDOT-AuNFs were supported on the surface of GOS by the interaction of the π-π packing between PEDOT and graphene oxide, a synergistic effect was produced to provide the second amplification for the aptasensor. PEDOT-AuNFs/GOS provided an ultrasensitive detection technique by multiple signal amplification for the electrochemical sensing of OTA. Consequently, this strategy not only endowed the aptasensor with high sensitivity but also needed no complicated signal amplification. The electrochemical sensor was fabricated successfully on a glassy carbon electrode to detect OTA with a linear response in the range of 0.01-20 ng L-1 and a limit of detection of 4.9 pg L-1. Moreover, it displayed good specificity, reproducibility and stability. The utilization of the proposed aptasensor for the quantitative determination of OTA in wine indicates that it can find promising applications in detecting OTA and even other mycotoxins in foodstuffs.


Subject(s)
Aptamers, Nucleotide/chemistry , Bridged Bicyclo Compounds, Heterocyclic/chemistry , Graphite/chemistry , Metal Nanoparticles/chemistry , Ochratoxins/analysis , Polymers/chemistry , Biosensing Techniques/methods , Electrochemical Techniques/instrumentation , Electrochemical Techniques/methods , Electrodes , Food Contamination/analysis , Gold/chemistry , Limit of Detection , Reproducibility of Results , Wine/analysis
15.
J Sep Sci ; 42(23): 3535-3543, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31556207

ABSTRACT

Silk fibers were carbonized to develop a biomass carbon material as an adsorbent for solid-phase microextraction. The surface structure of the carbonized silk fibers was characterized by scanning electron microscopy, and the graphitization degree was determined by Raman spectrometry. After carbonization under high temperature, the orderliness and structural regularity of carbon atoms on silk fibers were promoted. Extraction tube packed with carbonized silk fibers was prepared for in-tube solid-phase microextraction. Coupled with high performance liquid chromatography, it exhibited good extraction performance for hydrophobic polycyclic aromatic hydrocarbons. Main parameters including sampling volume, sampling rate, methanol content in sample, and desorption time were systematically investigated. Under the optimum conditions, the analysis method was established and it exhibited wide linear range (0.016-20 µg/L) with good linearity (correlation coefficient ≥ 0.9947), low limits of detection (0.005-0.050 µg/L), and high enrichment factors (1189-2775). Relative standard deviations (n = 3) for intraday (≤3.3%) and interday (≤9.6%) tests indicated that the extraction material had satisfactory repeatability. Finally, the analytical method was successfully applied to detect trace polycyclic aromatic hydrocarbons in real water samples, demonstrating its satisfactory practicability.

16.
Physica A ; 492: 2220-2236, 2018 Feb 15.
Article in English | MEDLINE | ID: mdl-32288104

ABSTRACT

This paper aims to study an SIS epidemic model with media coverage from a general deterministic model to a stochastic differential equation with environment fluctuation. Mathematically, we use the Markov semigroup theory to prove that the basic reproduction number R 0 s can be used to control the dynamics of stochastic system. Epidemiologically, we show that environment fluctuation can inhibit the occurrence of the disease, namely, in the case of disease persistence for the deterministic model, the disease still dies out with probability one for the stochastic model. So to a great extent the stochastic perturbation under media coverage affects the outbreak of the disease.

18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(5): 1177-81, 2015 May.
Article in English | MEDLINE | ID: mdl-26415423

ABSTRACT

The photoacoustic spectrum of glucose, sucrose and honey solutions in the visible range are measured by using the single-light photoacoustic spectrometer, and are compared with the spectra from spedtrophotometry method. The spectral characteristics of the above solutions show that the spectral background intensity and spectral profile have some differences for different kinds of solutions. The spectra of the three kinds of solutions all have strong peak value at 485 and 655 nm, but the intensity ratios between the two peaks are different. Besides, there are characteristic peak at 475, 576 and 630 nm for glucose, and the sucrose has apparent characteristic peak at 632 nm, these characteristic peaks can be used for detecting whether the natural honey has been added glucose or sucrose. By comparing two kinds of spectrum of the same solution, the intensity of photoacoustic spectrum is more responsive to the wavelength, indicating photoacoustic spectrometry has a higher sensitivity in the test of material composition.


Subject(s)
Honey/analysis , Spectrum Analysis , Acoustics , Glucose/analysis , Solutions , Sucrose/analysis
19.
Pak J Pharm Sci ; 27(5 Suppl): 1611-4, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25262506

ABSTRACT

A novel kind of cell-like particles as temperature-responsive catalysts was presented in this paper. First, uniform α-Fe2O3shuttle-like nanoparticles were prepared by homogeneous hydrolysis. Then, these α-Fe2O3particles were coated by Au nanoparticles (AuNPs), SiO2and poly (N-isopropylacrylamide) (PNIPAM), respectively. After the removal of SiO2layer by etching with HF solution, the cell-like particles were prepared when the α-Fe2O3, AuNPs, and PNIPAM were as cell nucleus, catalysts, and cell membranes, respectively. These cell-like particles showed a novel temperature-responsively catalytic performance because the PNIPAM shell could change its hydrophilicity and swelling capacity under different temperature. When the temperature was 25°C, the yield of 4-aminophenol (4-AP) from 4-nitrophenol (4-NP) by reduction of NaBH4was about 100% in 15 min, while the yield of 4-AP was about 90.5% in 40 min. when the temperature was 40°C.


Subject(s)
Acrylic Resins/chemistry , Metal Nanoparticles/chemistry , Catalysis , Gold , Temperature
20.
Front Immunol ; 15: 1412382, 2024.
Article in English | MEDLINE | ID: mdl-39308857

ABSTRACT

Background: Atopic dermatitis (AD) is a common chronic dermatitis of autoimmune origin that considerably affects the quality of life of patients. Ferroptosis, a newly regulated form of cell death, is essential for inflammation-related damage-associated molecular patterns (DAMPs). In this study, we aimed to identify ferroptosis regulators relevant to AD pathogenesis and reveal the mechanisms by which ferroptosis regulates the pathogenesis of AD. Methods: We analyzed the GEO AD cohorts (GSE16161, GSE32924, GSE107361, and GSE120721), identifying AD-related differentially expressed genes (DEGs) using edgeR. Co-expression and STRING database analyses were used to elucidate the interactions between DEGs and ferroptosis markers. Through functional enrichment analysis, we defined potential biological functions within the protein-protein interaction (PPI) network and developed FerrSig using LASSO regression. The utility of FerrSig in guiding the clinical management of AD was evaluated using the GSE32473 cohort. Subsequently, our in silico findings were confirmed, and mechanistic insights were expanded through both in vitro and in vivo studies, validating the relevance of FerrSig. Results: In the GEO AD cohort, 278 DEGs were identified, including seven ferroptosis signature genes. Co-expression analysis and STRING database review revealed a 63-node PPI network linked to cell cycle and pro-inflammatory pathways. Four ferroptosis genes (ALOXE3, FABP4, MAP3K14, and EGR1) were selected to create FerrSig, which was significantly downregulated in samples collected from patients with AD. In addition, immune-related signaling pathways were significantly differentially enriched between the stratifications of samples collected from patients with AD with high and low ferritin levels, whereas in the GSE32473 cohort, FerrSig was significantly increased in cohorts effectively treated with pimecrolimus or betamethasone. Finally, in vitro and in vivo models showed a notable FerrSig decrease in patients with AD versus healthy control. Treatment with betamethasone and tacrolimus restored FerrSig, and the magnitude of the increase in FerrSig was higher in samples collected from patients with AD with better efficacy assessments. In addition, FerrSig was significantly positively correlated with the ferroptosis inhibitors GPX4 and SLC7A11 and negatively correlated with reactive oxygen species (ROS) levels and p-STAT3/STAT3. This implies that the FerrSig signature genes may regulate ferroptosis through the JAK/STAT3 signaling pathway. Conclusion: Our study further explored the pathogenesis of AD, and FerrSig could serve as a potential biomarker for identifying AD morbidity risks and determining treatment efficacy.


Subject(s)
Computational Biology , Dermatitis, Atopic , Ferroptosis , Ferroptosis/genetics , Humans , Dermatitis, Atopic/genetics , Dermatitis, Atopic/immunology , Dermatitis, Atopic/drug therapy , Computational Biology/methods , Animals , Protein Interaction Maps , Gene Expression Profiling , Transcriptome , Mice , Databases, Genetic , Gene Regulatory Networks , Gene Expression Regulation , Signal Transduction , Biomarkers
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