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BACKGROUND: Deciphering the molecular dynamics (MD) of rotaxanes is crucial for designing and refining their applications in molecular devices. This study employed fluorine-19 nuclear magnetic resonance (19F NMR) and magnetic resonance imaging (MRI) to unveil the interplay between mechanical bonds and steric hindrance in a series of fluorinated rotaxanes. RESULTS: 1H/19F NMR revealed stable "Z"-shaped wheel conformations minimizing steric clashes and favoring π-π interactions with the axle. Utilizing fluorines and axle protons as reporters, 1H/19F relaxation rates and solid-state 19F NMR studies demonstrated that mechanical bond primarily governs wheel motion, while steric hindrance dictates axle movement. Intriguingly, mechanical bond mainly affects local axle groups, leaving distant ones minimally impacted. MD simulations corroborated these findings. Temperature-dependent 19F NMR indicated that energy input enhances rotational motion and wheel conformational transitions. Furthermore, the drastic increase in 19F relaxation rates upon mechanical bond formation and steric hindrance enables sensitive and selective 19F MRI visualization of MD changes. SIGNIFICANCE: This study, by elucidating the roles of internal and external factors on rotaxane molecular dynamics using 19F NMR/MRI, offers valuable insights that can advance the field of rotaxane-based molecular devices.
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The occurrence, distribution, and ecological risk assessment of 36 antibiotics from five groups, including macrolides (MLs), fluoroquinolones (FQs), tetracyclines (TCs), amphenicols (APs), and sulfonamides (SAs), were investigated for the first time in the Anning River, Sichuan Province, China. The results show that antibiotics were widely present in the sediments of the Anning River, with a total of 22 antibiotics detected. FQs were among the most abundant antibiotics, followed by TCs, MLs, APs, and SAs. The total concentrations of antibiotics in surface sediments varied from 0.05 to 53.35 ng/g, with an average of 8.09 ng/g. Among these groups, MLs, FQs, and TCs emerged as the predominant classes of antibiotics. The midstream sediments showed the highest residual levels of antibiotics, with lower levels observed in the downstream and upstream sediments. Anthropogenic activities, such as human clinical practices and animal breeding, might be sources of antibiotics released into the river. An ecological risk assessment revealed that trimethoprim from the SA group exhibited high risks, and MLs showed medium risks in the Anning River, whereas most antibiotics presented minimal to low risks. This study provides valuable information on antibiotic pollution in the upstream region of the Yangtze River, and future management measures are needed for the Anning River.
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BACKGROUND: Periodontitis is a common and harmful chronic inflammatory oral disease, characterized by the destruction of periodontal soft and hard tissues. The NLRP3 inflammasome-related pyroptosis and human periodontal ligament fibroblasts (hPDLFs) osteogenic dysfunction are involved in its pathogenesis. Studies have shown that lipoxin A4 is an endogenous anti-inflammatory mediator and BML-111 is a lipoxin A4 analog, which was found to have potent and durable anti-inflammatory effects in inflammatory diseases, but the mechanism remains unclear. The purpose of this study was to investigate whether BML-111 inhibits H2O2-induced dysfunction of hPDLFs, attenuates inflammatory responses, and identifies the underlying mechanisms. METHODS: The oxidative stress model was established with H2O2, and the cell proliferation activity was measured by CCK-8. ALP staining and alizarin red staining were used to detect the osteogenic differentiation capacity of cells; flow cytometry and ELISA were used to detect cell pyroptosis; we explored the effect of BML-111 on hPDLFs under oxidative stress by analyzing the results of PCR and Western blotting. The Nrf2 inhibitor ML385 was added to further identify the target of BML-111 and clarify its mechanism. RESULTS: BML-111 can alleviate the impaired cell proliferation viability induced by H2O2. H2O2 treatment can induce NLRP3 inflammasome-related pyroptosis, impairing the osteogenic differentiation capacity of hPDLFs. BML-111 can effectively alleviate H2O2-induced cellular dysfunction by activating the Nrf2/HO-1 signaling pathway. CONCLUSION: The results of this study confirmed the beneficial effects of BML-111 on H2O2-induced NLRP3 inflammasome-related pyroptosis in hPDLFs, and BML-111 could effectively attenuate the impaired osteogenic differentiation function. This beneficial effect is achieved by activating the Nrf2/HO-1 signaling pathway, therefore, our results suggest that BML-111 is a potential drug for the treatment of periodontitis.
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Periodontite , Piroptose , Humanos , Peróxido de Hidrogênio/farmacologia , Fator 2 Relacionado a NF-E2 , Proteína 3 que Contém Domínio de Pirina da Família NLR , Inflamassomos , Osteogênese , Ligamento Periodontal , Fibroblastos , Anti-InflamatóriosRESUMO
The three provinces of Northeast China are crucial to national commodity grain production. Soils in those areas have begun to severely degrade after long-term high-intensity use, with wind erosion as one of the main reasons. Based on meteorological and soil data from 1981 to 2019, we evaluated the spatial-temporal characteristics of wind erosion on bare land in the three provinces of Northeast China by using the revised wind erosion equation (RWEQ), and analyzed the contributions of meteorological factors to wind erosion on bare land. The results showed that, the meteorological factors of wind erosion were overall high in southwestern part and low in northeastern part of the region. In general, wind erosion in the region was substantial, especially in Liaoning. During the 39 years, wind erosion significantly increased throughout the whole year and during the growing season, at a rate of 129 and 105 t·km-2 per decade, respectively. The obvious increase in wind erosion was observed in the northwest Liaoning, Liaohe Plain, and Changbai Mountain area. Wind speed and air temperature were the main factors affecting wind erosion during the year and non-growing season, which contributed less during the growing season when precipitation contributed the most. We concluded that climate change has aggravated soil wind erosion in the three provinces of Northeast China.
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Mudança Climática , Vento , Solo , China , TemperaturaRESUMO
OBJECTIVE: Periodontitis is an inflammatory disease, while Nuclear factor erythroid-2 related factor 2 (Nrf2) acts a significant part in antioxidant, anti-inflammatory and immune response. However, the evidence in preclinical studies to certify Nrf2 can slow down the progression of periodontitis or facilitate its recovery is not enough. The present report aims to investigate the functional implications of Nrf2 in animal periodontitis models by evaluating the changes of Nrf2 levels and analyzing the clinical benefits of Nrf2 activation in the same models. DESIGN: We searched PubMed, Web of Science, EBSCO, CNKI, VIP, Wan Fang databases. The random-effects model was used to evaluate the mean differences (MD) and 95 % confidence intervals (95%CI) when the units of measurements of outcome indicators were the same, in contrast, the standardized mean differences (SMD) and 95%CI were evaluated while the units were different. RESULTS: 8 studies were included for quantitative synthesis. Compared with healthy groups, the expression of Nrf2 was markedly lower in periodontitis groups (SMD: -3.69; 95%CI: -6.25, -1.12). After administration of kinds of Nrf2-activators, a significant increase in Nrf2 levels (SMD: 2.01; 95%CI: 1.27, 2.76) was accompanied by a decrease in distance between cementoenamel junction and alveolar bone crest (CEJ-ABC) (SMD: -2.14; 95%CI: -3.29, -0.99) and an improvement of bone volume/tissue volume (BV/TV) (SMD:17.51; 95%CI: 16.24, 18.77) was evaluated compared with periodontitis groups. CONCLUSIONS: Nrf2 has a certain protective effect on periodontitis, however, the specific role Nrf2 plays in the development and severity of periodontitis remains to be demonstrated. PROSPERO registration number: CRD42022328008.
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Fator 2 Relacionado a NF-E2 , Periodontite , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Periodontite/tratamento farmacológico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Anti-Inflamatórios/uso terapêuticoRESUMO
OBJECTIVE: The present study aimed to investigate whether Ginsenoside Rg1 alleviated lipopolysaccharide (LPS) - induced pyroptosis of human periodontal ligament cells (HPDLCs) and further explore the underlying mechanism. DESIGN: Cell viability was detected using the CCK-8 assay. Proinflammatory cytokine secretion and lactate dehydrogenase release were examined by ELISA. Flow cytometry analysis was conducted to determine the pyroptosis ratio, and ATP production was estimated using the ATP assay kit. Fluorescence staining was utilized to visualize mitochondrial morphology and analyze mitochondrial reactive oxygen species (mtROS), and the mitochondrial membrane potential level. Western blot and qRT-PCR were used to determine the expression of signaling pathway-related proteins and mRNA, respectively. RESULTS: The results discovered that Ginsenoside Rg1 treatment enhanced cell viability in comparison to LPS stimulation, attenuated pyroptosis in HPDLCs, and reduced the release of lactate dehydrogenase, IL-1ß, and IL-18 significantly. Additionally, we found that Ginsenoside Rg1 upregulated ATP content and mitochondrial membrane potential level while reducing aberrant mitochondrial fission and mtROS production. Mechanistically, we found that Ginsenoside Rg1 upregulated dynamin-related protein 1 (Drp1) phosphorylation at Ser 637 in an AMP-activated protein kinase (AMPK)-dependent manner, and reduced pyroptosis-related proteins expression, including NLRP3, ASC, Caspase-1, and GSDMD-NT. CONCLUSIONS: These findings demonstrate that Ginsenoside Rg1 treatment attenuates LPS-induced pyroptosis and inflammation damage in HPDLCs, which may connect to the activation of the AMPK/Drp1/NLRP3 signaling pathway. Moreover, the results offer a potential theoretical foundation for applying Ginsenoside Rg1 in inflammatory diseases such as periodontitis.
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Lipopolissacarídeos , Piroptose , Humanos , Lipopolissacarídeos/farmacologia , Proteínas Quinases Ativadas por AMP , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ligamento Periodontal/metabolismo , Dinâmica Mitocondrial , Dinaminas , Trifosfato de Adenosina , Lactato DesidrogenasesRESUMO
OBJECTIVE: This study was aimed to determine whether N-acetylcysteine (NAC) could inhibit lipopolysaccharides / adenosine triphosphate (ATP)-induced pyroptosis and alleviate the damage of osteogenic differentiation in human periodontal ligament fibroblasts (hPDLFs). Furthermore, this study detected whether NAC acted effectively by modulating the silent information regulator 2 homolog 1 (SIRT1)/ the nuclear factor-κB (NF-κB)/Caspase-1 signaling pathway in hPDLFs. DESIGN: Cell Counting Kit-8 assay was employed to determine the appropriate concentration of NAC for the follow-up experiments. To explore the effect and the underlying mechanisms of NAC on pyroptosis and osteogenic differentiation in hPDLFs, intracellular reactive oxygen species levels were detected using 2',7'-Dichlorodihydrofluorescein Diacetate kits. Moreover, SIRT1 inhibitor, SIRT1 activator, NF-κB inhibitor and Caspase-1 inhibitor were applied, the incidence of pyroptosis was detected by flow cytometry, the osteogenic differentiation of hPDLFs was observed using alkaline phosphatase and alizarin red staining, Real-time quantitative polymerase chain reaction and Western Blot were used to detect the expression of relevant factors, the release of interleukin-1ß, interleukin-18 and lactate dehydrogenase were detected by Enzyme-linked immunosorbent assay. RESULTS: The results demonstrated that NAC protected hPDLFs from lipopolysaccharides/ATP-induced damage, alleviating pyroptosis and osteogenic differentiation dysfunction. Moreover, NAC abrogated the inhibition of SIRT1 activity by scavenging reactive oxygen species, thereby reduced pyroptosis and osteogenic differentiation dysfunction by inhibiting the NF-κB/Caspase-1signaling pathway. CONCLUSION: NAC could inhibit pyroptosis and osteogenic differentiation dysfunction of hPDLFs by scavenging reactive oxygen species to regulate the SIRT1/NF-κB/Caspase-1 signaling axis.
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Acetilcisteína , NF-kappa B , Humanos , NF-kappa B/metabolismo , Acetilcisteína/farmacologia , Osteogênese , Caspase 1/metabolismo , Piroptose , Espécies Reativas de Oxigênio/metabolismo , Ligamento Periodontal , Lipopolissacarídeos/farmacologia , Sirtuína 1/metabolismo , Sirtuína 1/farmacologia , Células Cultivadas , Transdução de Sinais , Diferenciação Celular , Fibroblastos , Trifosfato de Adenosina/metabolismoRESUMO
BACKGROUND AND OBJECTIVE: Cardiotocography, commonly called CTG, has become an indispensable auxiliary examination in obstetrics. Generally, CTG is provided in the form of a report, so the fetal heart rate and uterine contraction signals have to be extracted from the CTG images. However, most studies focused on reading data for a single curve, and the influence of complex backgrounds was usually not considered. METHODS: An efficient signal extraction method was proposed for the binary CTG images with complex backgrounds. Firstly, the images' background grids and symbol noise were removed by templates. Then a morphological method was used to fill breakpoints of curves. Moreover, the projection map was utilized to localize the area and the starting and ending positions of curves. Subsequently, data of the curves were extracted by column scanning. Finally, the amplitude of the extracted signal was calibrated. RESULTS: This study had tested 552 CTG images simulated using the CTU-UHB database. The correlation coefficient between the extracted and original signals was 0.9991 ± 0.0030 for fetal heart rate and 0.9904 ± 0.0208 for uterine contraction, and the mean absolute error of fetal heart rate and uterine contraction were 2.4658 ± 1.8446 and 1.8025 ± 0.6155, and the root mean square error of fetal heart rate and uterine contraction were 4.2930 ± 2.9771 and 2.5214 ± 0.9640, respectively. After being validated using 293 clinical authentic CTG images, the extracted signals were remarkably similar to the original counterparts, and no significant differences were observed. CONCLUSIONS: The proposed method could effectively extract the fetal heart rate and uterine contraction signals from the binary CTG images with complex backgrounds.
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Cardiotocografia , Obstetrícia , Cardiotocografia/métodos , Bases de Dados Factuais , Feminino , Frequência Cardíaca Fetal/fisiologia , Humanos , Gravidez , Contração UterinaRESUMO
BACKGROUND: The diagnosis of cardiac abnormalities based on heart sound signal is a research hotspot in recent years. The early diagnosis of cardiac abnormalities has a crucial significance for the treatment of heart diseases. METHODS: For the sake of achieving more practical clinical applications of automatic recognition of cardiac abnormalities, here we proposed a novel fuzzy matching feature extraction method. First of all, a group of Gaussian wavelets are selected and then optimized based on a template signal. Convolutional features of test signal and the template signal are then computed. Matching degree and matching energy features between template signal and test signal in time domain and frequency domain are then extracted. To test performance of proposed feature extraction method, machine learning algorithms such as K-nearest neighbor, support vector machine, random forest and multilayer perceptron with grid search parameter optimization are constructed to recognize heart disease using the extracted features based on phonocardiogram signals. RESULTS: As a result, we found that the best classification accuracy of random forest reaches 96.5% under tenfold cross validation using the features extracted by the proposed method. Further, Mel-Frequency Cepstral Coefficients of phonocardiogram signals combing with features extracted by our algorithm are evaluated. Accuracy, sensitivity and specificity of integrated features reaches 99.0%, 99.4% and 99.7% respectively when using support vector machine, which achieves the best performance among all reported algorithms based on the same dataset. On several common features, we used independent sample t-tests. The results revealed that there are significant differences (p < 0.05) between 5 categories. CONCLUSION: It can be concluded that our proposed fuzzy matching feature extraction method is a practical approach to extract powerful and interpretable features from one-dimensional signals for heart sound diagnostics and other pattern recognition task.
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Cardiopatias , Processamento de Sinais Assistido por Computador , Algoritmos , Cardiopatias/diagnóstico , Humanos , Aprendizado de Máquina , Redes Neurais de Computação , Máquina de Vetores de SuporteRESUMO
The aim of this in vitro study was to estimate the effect of the species concentration of 45S5 bioactive glass (BAG) used as pretreatment on the microshear bond strength (MSBS) of dental fluorosis (DF). Based on the Thylstrup and Fejerskov index, 80 teeth were randomly divided equally into four groups: TFI 0, sound dentin; TFI 1-3, mild fluorosis; TFI 4-5, moderate fluorosis; and TFI 6-9, severe fluorosis. Each group was randomized into five subgroups. After preparing the dentin hypersensitivity model of DF, the dentin was pretreated as follows, Subgroup 1: deionized water (Control group); Subgroup 2: 1% BAG; Subgroup 3: 5% BAG; Subgroup 4: 10% BAG, and Subgroup 5: 20% BAG. Stochastically one specimen was selected from each subgroup for scanning electron microscope and energy dispersive spectrometer analysis. After being made of resin-tooth bonding samples, the remains were in water bath at 37 °C for 24 hr. Subsequently, samples from each subgroup were randomly selected to test MSBS without aging, or after a thermocycle of 5,000 and 10,000 times, respectively. The fracture modes were analyzed. Compared with the group of 1% BAG and Control, the exposure area of tubules in 5%, 10%, and 20% BAG group had significant difference (p < .05). MSBS results indicated that there were significant differences between 10% BAG with other groups. The 20% BAG group showed the lowest MSBS among all groups. Pretreatment of 10% BAG solution may be conductive to enhance the bond strength of DF, while 20% BAG solution adversely.
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Colagem Dentária , Fluorose Dentária , Resinas Compostas/química , Dentina , Adesivos Dentinários/química , Vidro , Humanos , Teste de Materiais , Cimentos de Resina/química , ÁguaRESUMO
Herein, selenium-containing polysaccharide from Spirulina platensis (Se-SPP) was prepared and its structural characteristics and protective role against Cd-induced toxicity in vivo and in vitro were investigated. Se-SPP was alkali-extracted from selenium-containing Spirulina platensis which was cultured in Zarrouk medium supplemented with Na2SeO3. The contents of carbohydrate, protein, uronic acid, sulfate and elements (including Se, C, H, O, N, and S) as well as the monosaccharide composition, molecular weight, surface morphology and FT-IR spectra of Se-SPP was compared to that of selenium-free polysaccharide (SPP). The results revealed that SPP and Se-SPP were both high-molecular-weight heteropolysaccharide with similar molecular weight and monosaccharide composition but significantly different selenium content, indicating that the covalently-bonding of a small amount of selenium did not destroy the original structure of polysaccharide. Furthermore, CdCl2 was utilized to build Cd-intoxicated cells model in vitro and rats model in vivo respectively. Then, the protective effect of Se-SPP against cadmium-induced toxicity was assessed. The results demonstrated that Se-SPP treatment provided significant protection against Cd-induced toxicity, which was superior compared to that of SPP or Na2SeO3 alone. The enhancement of protective role may be affected by the covalently-bonding of selenium to polysaccharide.
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Cádmio/toxicidade , Polissacarídeos Bacterianos , Selênio , Spirulina/química , Animais , Células HEK293 , Humanos , Masculino , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/farmacologia , Ratos , Ratos Sprague-Dawley , Selênio/química , Selênio/farmacologiaRESUMO
BACKGROUND: Non-coding RNAs are endogenous regulators of gene expression that have been implicated in the pathogenesis of various diseases, including osteoarthritis (OA). Long non-coding RNA nuclear enriched abundant transcript 1 (NEAT1) and miR-16-5p are up-regulated in OA tissues; however, their functions have not been clarified. METHODS: Chondrocyte ATDC5 was used as a cell model. NEAT1 overexpression and knockdown cells were established by transfection with lipofectamine. miR-16-5p was also transfected into the cells using lipofectamine. Moreover, cell proliferation was examined using cell counting kit-8 assays. Cell apoptosis was evaluated by flow cytometry. The interaction between NEAT1 and miR-16-5p was validated by a Quantitative real-time RT-PCR (qRT-PCR) and dual-luciferase reporter assays. RESULTS: NEAT1 could increase cell viability and decrease apoptosis of ATDC5 cells, whereas miR-16-5p had the opposite effects. NEAT1 could specifically bind to miR-16-5p and reduce its expression. CONCLUSIONS: The suppression of miR-16-5p, as mediated by NEAT1 overexpression, could promote proliferation and inhibit apoptosis of chondrocytes. It was also revealed that NEAT1 is a "double-edged sword" during the development of OA.
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Proliferação de Células/genética , MicroRNAs/genética , Osteoartrite/genética , RNA Longo não Codificante/genética , Apoptose/genética , Linhagem Celular , Condrócitos/metabolismo , Condrócitos/patologia , Feminino , Citometria de Fluxo , Regulação da Expressão Gênica/genética , Humanos , Masculino , Osteoartrite/patologiaRESUMO
BACKGROUND Hepatitis B virus (HBV) genotypes show genomic variations, resulting in different CpG islands in each HBV genotypes or subgenotype. This study aimed to establish reference sequences for each HBV subgenotype of A-H genotypes and to analyze the characteristics of the CpG islands. MATERIAL AND METHODS There were 3,037 retrieved whole-genome sequences of HBV genotypes A-H from GenBank, 28 subgenotype reference sequences were established for these genotypes. CpG islands of the subgenotype reference sequences were analyzed, and 939 strains were selected from the 3,037 genomic sequences. Differences in CpG islands between subgenotypes were compared using the chi-squared and non-parametric tests. RESULTS Of the 28 subgenotype reference sequences established, 11 subgenotype reference sequences lacked CpG island I, and only F4 contained a new CpG island. Of all selected strains, 48.35% (454/939) contained three traditional CpG islands I, II, and III (no new islands); 45.05% (423/939) lacked CpG island I; 38.98% (366/939) contained only CpG islands II and III; and 12.46% (117/939) contained new islands (genotypes A1, D7) (genotype G had no new islands). Strains with or without CpG island I, or new islands between subgenotypes of each HBV genotype were significantly different (P<0.05). Strains containing CpG islands I, II, and III and new islands among different subtypes in HBV genotypes A, C, and F were significantly different (P<0.05). CONCLUSIONS Different HBV genotypes and subgenotypes had characteristic CpG island patterns. Strains with or without CpG island I, or new islands among subgenotypes of each HBV genotype, were significantly different.
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Ilhas de CpG/genética , Vírus da Hepatite B/genética , DNA Viral , Bases de Dados Genéticas , Genótipo , Hepatite B/genética , FilogeniaRESUMO
We developed a rapid immunochromatographic strip (ICS) test for lily mottle virus (LMoV). The test is based on a double-antibody sandwich format and employs two distinct anti-LMoV polyclonal antibodies (IgG3 and IgG4). The first antibody, IgG3 was conjugated with colloidal gold, and the second antibody, IgG4 was used as the capture antibody at the test line. The performance of the ICS test was evaluated and the results obtained were compared with a quadruplex RT-PCR assay. When serial dilutions of purified LMoV were tested, the LMoV detection limit of the ICS test was 8.0 × 10(-9) mg/mL, which was in complete agreement with the results of quadruplex RT-PCR. Compared with quadruplex RT-PCR, the specificity and sensitivity of ICS were 98.7 and 100%, respectively. There was therefore significant agreement between the results obtained from the two tests (κ = 0.982). The ICS test therefore appears to be broadly applicable, and will be especially useful in the field, as well as in areas without laboratory facilities, to support efforts to detect and control LMoV.