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1.
Sensors (Basel) ; 23(22)2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-38005418

RESUMEN

Single-circle detection is vital in industrial automation, intelligent navigation, and structural health monitoring. In these fields, the circle is usually present in images with complex textures, multiple contours, and mass noise. However, commonly used circle-detection methods, including random sample consensus, random Hough transform, and the least squares method, lead to low detection accuracy, low efficiency, and poor stability in circle detection. To improve the accuracy, efficiency, and stability of circle detection, this paper proposes a single-circle detection algorithm by combining Canny edge detection, a clustering algorithm, and the improved least squares method. To verify the superiority of the algorithm, the performance of the algorithm is compared using the self-captured image samples and the GH dataset. The proposed algorithm detects the circle with an average error of two pixels and has a higher detection accuracy, efficiency, and stability than random sample consensus and random Hough transform.

2.
J Asian Nat Prod Res ; 24(8): 754-760, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34647847

RESUMEN

Quercetin (1) was converted into quercetin 7-O-succinyl glucoside (2) by used Bacillus amyloliquefaciens FJ18 as a solvent-resistant whole-cell biocatalyst. The structure of the new compound was confirmed by LC-MS analysis and NMR spectroscopy. The water-solubility of this novel quercetin 7-O-succinyl glucoside (2) was approximately 1000 times higher than that of native quercetin (2). Quercetin (1) and quercetin 7-O-succinyl glucoside (2) exhibited significant DPPH scavenging capacity with IC50 values of 23.55 and 36.05 µM, respectively. Both compounds showed moderate cytotoxic effects against the two human cancer cell lines (MCF-7 and HepG2) with IC50 values ranging from 39.45-63.38 µM.


Asunto(s)
Antioxidantes , Quercetina , Antioxidantes/farmacología , Glucósidos/química , Humanos , Estructura Molecular , Rutina , Agua
3.
Appl Microbiol Biotechnol ; 105(18): 6707-6718, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34476516

RESUMEN

Pneumocandin B0, the precursor of the antifungal drug caspofungin, is a lipohexapeptide produced by the fungus Glarea lozoyensis. Oxidative stress and the resulting production of reactive oxygen species (ROS) are known to be involved in the regulation of pneumocandin B0 biosynthesis. In this study, the Glyap1 gene of Glarea lozoyensis, a homologue of the yeast redox regulator YAP1, was knocked out. The intracellular ROS levels of the resulting ΔGlyap1 strain were higher than in the wild-type strain, which was caused by the downregulated expression of superoxide dismutase (SOD) and catalase (CAT). Compared with the wild-type strain, ΔGlyap1 exhibited an oxidative phenotype throughout its life cycle, which resulted in significantly higher pneumocandin B0 production per unit biomass. In addition, ΔGlyap1 showed growth inhibition and decreased pneumocandin B0 production in the presence of CCl4, which leads to strong oxidative stress. To overcome the strain's sensitivity, a three-stage antioxidant addition strategy was developed. This approach significantly improved the growth of ΔGlyap1 while maintaining a high pneumocandin B0 production per unit biomass, which reached 38.78 mg/g DCW. Notably, this result represents a 50% increase over the wild-type strain. These findings provide new insights into the regulatory mechanisms that control pneumocandin B0 production under oxidative stress, which may be applied to improve the production of other secondary metabolites. KEY POINTS: • Glyap1 is involved in expression of redox and pneumocandin B0 synthesis-related genes. • Addition of a three-stage antioxidant alleviated the sensitivity of ΔGlyap1 strain. • The yield of pneumocandin B0 per unit biomass of ΔGlyap1 strain was 38.78 mg/g DCW.


Asunto(s)
Ascomicetos , Equinocandinas , Ascomicetos/genética , Ascomicetos/metabolismo , Equinocandinas/metabolismo , Oxidación-Reducción , Estrés Oxidativo , Especies Reactivas de Oxígeno
4.
BMJ Open ; 14(4): e079354, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38569706

RESUMEN

INTRODUCTION: Specific treatment for diabetic peripheral neuropathy (DPN) is still lacking, and acupuncture may relieve the symptoms. We intend to investigate the efficacy and safety of electro-acupuncture (EA) in alleviating symptoms associated with DPN in diabetes. METHODS AND ANALYSIS: This multicentre, three-armed, participant- and assessor-blind, randomised, sham-controlled trial will recruit 240 eligible participants from four hospitals in China and will randomly assign (1:1:1) them to EA, sham acupuncture (SA) or usual care (UC) group. Participants in the EA and SA groups willl receive either 24-session EA or SA treatment over 8 weeks, followed by an 8-week follow-up period, while participants in the UC group will be followed up for 16 weeks. The primary outcome of this trial is the change in DPN symptoms from baseline to week 8, as rated by using the Total Symptom Score. The scale assesses four symptoms: pain, burning, paraesthesia and numbness, by evaluating the frequency and severity of each. All results will be analysed with the intention-to-treat population. ETHICS AND DISSEMINATION: The protocol has been approved by the Ethics Committee of the Beijing University of Chinese Medicine (Identifier: 2022BZYLL0509). Every participant will be informed of detailed information about the study before signing informed consent. The results of this trial will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: ChiCTR2200061408.


Asunto(s)
Terapia por Acupuntura , Diabetes Mellitus , Neuropatías Diabéticas , Electroacupuntura , Humanos , Neuropatías Diabéticas/terapia , Dolor , China , Beijing , Resultado del Tratamiento , Electroacupuntura/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(8): 2087-91, 2009 Aug.
Artículo en Zh | MEDLINE | ID: mdl-19839314

RESUMEN

Due to its many advantages, such as miniaturization, high accuracy, high resolution, fast scanning speed, increased robustness and good stability, acousto-optic tunable filter (AOTF)-near infrared (NIR) spectrometer has been successfully applied in many fields. However, up to now, the commercial AOTF-NIR spectrometers can only be used for liquid and solid detection, but not for the detection of gaseous samples. In the present paper, the feasibility of quantitative analysis of gaseous mixtures by using AOTF-NIR spectrometer was investigated. A homemade gas cell was assembled to an AOTF-NIR spectrometer with probe for liquid detection to obtain NIR spectra of detected gas samples. The gas samples were composed of two groups: single-component CH4 and ternary component gaseous mixture of CH4, C2 H6, and C3 H8. The detection ability of fitted AOTF-NIR spectrometer was tested firstly. Comparing the absorption spectra of various concentrations, the absorbance of CH4 in absorption bands obviously increased with concentration increasing when the concentration was over 0.1%. According to the detection results, the lower limit of detection (LLD) of the AOTF-NIR spectrometer with gas cell was estimated to be 898 microL x L(-1). Subsequently, the NIR spectra of ternary mixtures were collected. The kernel partial least squares (KPLS) regression was employed to create the quantitative analysis model of three components gases. To evaluate the analysis ability of KPLS model, the PLS model was also created. The prediction results of the identical testing set show that the root mean square error of prediction (RMSEP) of three components predicted by KPLS model was 1.08%, 0.87%, and 0.79%, respectively, less than the RMSEP by PLS model. The exploratory work indicates that accurate quantitative analysis of ternary component alkane gaseous mixtures can be achieved by fitted AOTF-NIR spectrometer despite of some limitations, and KPLS regression is an excellent approach to NIR spectra analysis.

6.
Eur J Pharmacol ; 855: 208-215, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-30880180

RESUMEN

6"-O-succinylapigenin [apigenin-7-O-(6'-O-succinyl)-glucoside], a novel compound, is identified in chamomile. Although it is highly produced by Bacillus amyloliquefaciens FJ18, its bioactivity remains unknown. The neuroprotective effects and antioxidative mechanism of 6''-O-succcinylapigenin in the middle cerebral artery occlusion model in male rats was investigated in this study. The structure of this compound was determined by spectroscopic data analysis. After 2 h of occlusion and 24 h of reperfusion, magnetic resonance imaging and assessed neurological scores following middle cerebral artery occlusion (MCAO) in male rats to determine the infarction size and neurological deficits, respectively. In addition, we tested protein levels of the nuclear factor E2-related factor 2 (Nrf2), Kelch-like ECH-associated protein1 (Keap1), heme oxygenase-1 (HO-1), and extracellular-signal-regulated kinase (ERK), to investigate the mechanism of antioxidative action of 6''-O-succcinylapigenin. Finally, we employed immunofluorescence to determine the location of Nrf2 and Keap1 in HT22 cells cultured in vitro. Our results revealed that administration of 6''-O-succcinylapigenin induced a decrease in both infarct volume and neurological scores following MCAO, and significantly increased the activity of HO-1 and nuclear Nrf2 in vivo. Similarly, immunofluorescence assays indicated that Nrf2 is highly expressed in the nucleus following treatment with 6''-O-succcinylapigenin in vitro. Our study suggests that 6''-O-succcinylapigenin exerts an anti-ischemic effect by activating the ERK/Nrf2/HO-1 pathway.


Asunto(s)
Apigenina/química , Apigenina/farmacología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Hemo Oxigenasa (Desciclizante)/metabolismo , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Factor 2 Relacionado con NF-E2/metabolismo , Agua/química , Animales , Antioxidantes/metabolismo , Apigenina/uso terapéutico , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/patología , Masculino , Malondialdehído/metabolismo , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Ratas , Ratas Sprague-Dawley , Solubilidad , Superóxido Dismutasa/metabolismo
7.
Zhen Ci Yan Jiu ; 44(2): 113-9, 2019 Feb 25.
Artículo en Zh | MEDLINE | ID: mdl-30945487

RESUMEN

OBJECTIVE: To observe the effect of moxibustion at "Zusanli" (ST36) on metabolites of gastric tissue in chronic atrophic gastritis (CAG) rats, so as to explore the correlation between Yangming Meridian and stomach based on metabolomics. METHODS: Fifty-six SD rats were randomly divided into normal, normal + moxibustion, model and model + moxibustion groups (n=14 rats/group). The CAG model was established by gavage of N-methyl-N'-nitro-N-nitroso-guanidine (MNNG) solution and irregular diet for 12 weeks. Moxibustion was applied to ST36 and "Zhongwan" (CV12) for 15 min, once daily for two weeks in the normal+ moxibustion group and model+moxibustion group. The histopathological changes of the gastric tissue were observed by H.E. staining. 1H nuclear magnetic resonance (1H NMR) spectroscopy was used to detect gastric tissue metabolites and the data were analyzed using the Chenomx NMR Suite software. RESULTS: After modeling, the regional gastric tissue showed pale thinner gastric wall, and reduction of regional glands with necrosis and disordered arrangement, epithelial cell exfoliation, lymphocyte infiltration as well as scattered punctate hemorrhage, which was evidently milder in the model + moxibustion group. The metabolites of lactic acid, glutathione, N-acetylaspartate, uridine diphosphate glucose and muscle sugar in the gastric tissue in the model group were increased compared with those in the normal group (P<0.05), and the metabolites of leucine, betaine, phosphorylcholine, and uracil were decreased (P<0.05). The glutathione, N-acetylaspartate, phosphorylcholine and uracil in the model+moxibustion group were significantly reversed relevant to the model group (P<0.05). The inositol in gastric tissue were significantly increased (P<0.05), 3-hydroxybutyric acid, serine and uridine diphosphate glucose were significantly decreased (P<0.05) in the normal + moxibustion group than in the normal group. CONCLUSION: Moxibustion has a good efficacy in regulating some metabolic substances such as glutathione, N-acetylaspartic acid, choline phosphate and uracil of CAG rats, suggesting a specific relationship between the Stomach Meridian and the stomach.


Asunto(s)
Gastritis Atrófica , Moxibustión , Puntos de Acupuntura , Animales , Metabolómica , Ratas , Ratas Sprague-Dawley
8.
Chin Med ; 14: 18, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31080495

RESUMEN

BACKGROUND: Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder, which is commonly treated with antidiarrhoeal, antispasmodics, serotonergic agents or laxative agents. These treatments provide relief for IBS symptoms but may also lead to undesired side effects. Previously, herb-partitioned moxibustion (HPM) treatment has been demonstrated to be effective in ameliorating symptoms of IBS. However, the underlying mechanism of this beneficial treatment is yet to be established. The aim of the current study was to systematically assess the metabolic alterations in response to diarrhea-predominant IBS (IBS-D) and therapeutic effect of HPM. METHODS: Proton nuclear magnetic resonance spectroscopy (1H NMR)-based metabolomics approach was used to investigate fecal and serum metabolome of rat model of IBS-D with and without HPM treatment. RESULTS: The current results showed that IBS-induced metabolic alterations in fecal and serum sample include higher level of threonine and UDP-glucose together with lower levels of aspartate, ornithine, leucine, isoleucine, proline, 2-hydroxy butyrate, valine, lactate, ethanol, arginine, 2-oxoisovalerate and bile acids. These altered metabolites potentially involve in impaired gut secretory immune system and intestinal inflammation, malabsorption of nutrients, and disordered metabolism of bile acids. Notably, the HPM treatment was found able to normalize the Bristol stool forms scale scores, fecal water content, plasma endotoxin level, and a number of IBS-induced metabolic changes. CONCLUSIONS: These findings may provide useful insight into the molecular basis of IBS and mechanism of the HPM intervention.

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