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2.
Nucleic Acids Res ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38864377

RESUMEN

Histones are essential for genome compaction and transcription regulation in eukaryotes, where they assemble into octamers to form the nucleosome core. In contrast, archaeal histones assemble into dimers that form hypernucleosomes upon DNA binding. Although histone homologs have been identified in bacteria recently, their DNA-binding characteristics remain largely unexplored. Our study reveals that the bacterial histone HBb (Bd0055) is indispensable for the survival of Bdellovibrio bacteriovorus, suggesting critical roles in DNA organization and gene regulation. By determining crystal structures of free and DNA-bound HBb, we unveil its distinctive dimeric assembly, diverging from those of eukaryotic and archaeal histones, while also elucidating how it binds and bends DNA through interaction interfaces reminiscent of eukaryotic and archaeal histones. Building on this, by employing various biophysical and biochemical approaches, we further substantiated the ability of HBb to bind and compact DNA by bending in a sequence-independent manner. Finally, using DNA affinity purification and sequencing, we reveal that HBb binds along the entire genomic DNA of B. bacteriovorus without sequence specificity. These distinct DNA-binding properties of bacterial histones, showcasing remarkable similarities yet significant differences from their archaeal and eukaryotic counterparts, highlight the diverse roles histones play in DNA organization across all domains of life.


Histones, traditionally known for organizing and regulating DNA in eukaryotes and archaea, have recently been discovered in bacteria, opening up a new frontier in our understanding of genome organization across the domains of life. Our study investigates the largely unexplored DNA-binding properties of bacterial histones, focusing on HBb in Bdellovibrio bacteriovorus. We reveal that HBb is essential for bacterial survival and exhibits DNA-binding properties similar to archaeal and eukaryotic histones. However, unlike eukaryotic and archaeal histones, which wrap DNA, HBb bends DNA without sequence specificity. This work not only broadens our understanding of DNA organization across different life forms but also suggests that bacterial histones may have diverse roles in genome organization.

3.
Biomarkers ; 29(5): 276-284, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38767408

RESUMEN

BACKGROUND: Bladder cancer (BC) is one of the ten most common cancers worldwide with late detection and early age of diagnosis. There is abundant evidence that early detection and timely intervention can lead to a better prognosis of BC. Substantial evidence has indicated that microRNAs (miRNAs) are specific to different tumour types and are remarkably stable, indicating that serum miRNAs may serve as potential cancer diagnostic markers. This study aimed to identify suitable serum miRNAs to create a panel that can be used to diagnose primary BC. METHODS: In this study, 18 miRNAs that were differentially expressed in BC were obtained from the PubMed or Gene Expression Omnibus database. Then, 18 BC-related-miRNAs were verified in screening and validation sets created using 56 (28 primary BC vs. 28 NCs) and 168 (84 primary BC vs. 84 NCs) serum samples, respectively. Quantitative reverse transcription-PCR (qRT-PCR) was performed to verify the identity of the differential miRNAs. A multi-miRNA panel with superior diagnostic performance was constructed. TCGA and KEGG databases were used to conduct the survival analysis and bioinformatics analysis, respectively. RESULTS: Six serum miRNAs (miR-221-5p, miR-181a-5p, miR-98-5p, miR-15a-5p, miR-222-3p, and miR-197-3p) were significantly aberrantly expressed in the BC patients, while four miRNAs from among them (miR-221-5p, miR-181a-5p, miR-15a-5p, miR-222-3p) were assembled into a panel that showed high diagnostic value (AUC = 0.875, 95% CI: 0.815 - 0.921; sensitivity: 82.14%; and specificity: 85.71%) based on the logistic regression analysis. The survival analysis showed that miR-181a-5p was closely associated with BC prognosis (Log-rank p-value < 0.05). CONCLUSION: The combination of the four miRNAs (miR-221-5p, miR-181a-5p, miR-15a-5p and miR-222-3p) may be a novel non-invasive serological biomarker for BC screening.


Early detection and timely intervention can lead to a better prognosis of bladder cancer.This study aimed to identify suitable serum miRNAs to create a panel that can be used to diagnose primary bladder cancer.


Asunto(s)
Biomarcadores de Tumor , MicroARNs , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/sangre , Neoplasias de la Vejiga Urinaria/diagnóstico , MicroARNs/sangre , MicroARNs/genética , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/genética , Femenino , Masculino , Persona de Mediana Edad , Pronóstico , Regulación Neoplásica de la Expresión Génica , Anciano , Perfilación de la Expresión Génica
4.
J Environ Manage ; 354: 120314, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38401493

RESUMEN

In the context of rapid urban expansion, the interaction between humanity and nature has become more prominent. Urban land and rivers often exist as distinct entities with limited material exchange. However, during rainfall, these two systems interconnect, resulting in the transfer of land-derived pollutants into rivers. Such transfer significantly increases river pollutant levels, adversely affecting water quality. Therefore, developing a water quality simulation and prediction model is crucial. This model should effectively illustrate pollutant movement and dispersion during rain events. This study proposes a comprehensive model that merges the Storm Water Management Model (SWMM) with the Environmental Fluid Dynamics Code (EFDC). This integrated model assesses the spread and dispersion of pollutants, including Ammonia Nitrogen (NH3-N), Total Phosphorus (TP), Total Nitrogen (TN), and Chemical Oxygen Demand (COD), within urban water cycles for various rainfall conditions, thus offering critical theoretical support for managing the water environment. The application of this model under different rainfall intensities (light, moderate and heavy) provides vital insights. During light rainfall, the river's natural purification process can sustain surface water quality at Class IV. Moderate rainfall causes accumulation of pollutants, reducing water quality to Class V. Conversely, heavy rainfall rapidly increases pollutant concentrations due to higher inflow, pushing the river to a degraded Class V status, which is beyond its natural purification capacity, necessitating engineering solutions to reattain Class IV quality. Furthermore, pollutant accumulation in downstream river sections is more influenced by flow rate than by rainfall intensity. In summary, the SWMM-EFDC integrated model proves highly effective in predicting river water quality, thereby significantly aiding urban water pollution control.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Contaminantes Químicos del Agua/análisis , Calidad del Agua , Fósforo/análisis , Lluvia , Nitrógeno/análisis , China
5.
BMC Anesthesiol ; 24(1): 48, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38308200

RESUMEN

PURPOSE: Previous reports argue that preoperative sleep conditions of patients can influence the dosage of general anaesthesia drugs. Therefore, we aimed to investigate the dose-effect relationship of preoperative sleep disorders on the induction of general anaesthesia with remimazolam tosilate and calculate the Median effective (ED50) and 95% effective (ED95) dosages. METHODS: Included in our study were 56 patients who underwent laparoscopic cholecystectomy at our hospital. A separate group of 27 patients with sleep disorders (SD group) and 29 patients without sleep disorders (NSD group) using the Pittsburgh Sleep Quality Index (PSQI) were also included. According to the Dixon 'up-and-down' design, patients received remimazolam at preselected concentrations starting at 0.2 mg/kg. After the administration of remimazolam, loss of consciousness was observed. By observing whether consciousness disappeared within a minute, we adjusted the dose of remimazolam by 0.1 mg/kg (up and down) in the following patient. The Median effective dose (ED50), 95% effective dose (ED95), and 95% confidence interval (CI) of remimazolam for effective sedation were calculated. RESULTS: The ED50 of remimazolam was 0.226 mg/kg (95%CI 0.221-0.232 mg/kg) in the SD group and 0.191 mg/kg (95%CI, 0.183-0.199 mg/kg) in the NSD group. The ED95 of remimazolam was 0.237 mg/kg (95%CI 0.231-0.262 mg/kg) in the SD group and 0.209 mg/kg (95%CI 0.200-0.254 mg/kg) in the NSD group. CONCLUSIONS: In the SD group, the ED50 and ED95 of remimazolam during anaesthesia induction were 0.226 and 0.237 mg/kg, respectively. The induction dose of remimazolam in the SD group was significantly higher than that in the NSD group.


Asunto(s)
Bencenosulfonatos , Benzodiazepinas , Colecistectomía Laparoscópica , Propofol , Trastornos del Sueño-Vigilia , Humanos , Anestesia General
6.
Opt Lett ; 48(23): 6152-6155, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38039214

RESUMEN

The digital-analog radio-over-fiber (DA-RoF) scheme offers a high-fidelity and spectrally efficient solution for future mobile fronthaul. However, to be implemented in the low-cost directly modulated laser with direct detection (DML-DD) link, both the digital and analog parts in DA-RoF modulation would suffer from the composite second-order (CSO) and composite triple beat (CTB) caused by the chirp-dispersion interaction. In this Letter, we propose and experimentally demonstrate a computationally efficient composite triple beat cancellation (CTB-C) algorithm for DA-RoF fronthaul in the dispersion-uncompensated C-band DML-DD link. The CSO and CTB are suppressed at the receiver-side DSP based on the theoretical model of these nonlinear distortions. In the proof-of-concept experiment, a 1.2-dB improvement in the recovered signal-to-noise ratio (SNR) is obtained with 5.5-GHz 1024-QAM orthogonal frequency division multiplexing (OFDM) signal after 10-km standard single-mode fiber (SSMF) transmission. The proposed CTB-C technique does not require the training process and performs close to the Volterra-based feed-forward equalizer (VFE) under the complexity constraint.

7.
Front Plant Sci ; 14: 1124939, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37426958

RESUMEN

The field of computer vision has shown great potential for the identification of crops at large scales based on multispectral images. However, the challenge in designing crop identification networks lies in striking a balance between accuracy and a lightweight framework. Furthermore, there is a lack of accurate recognition methods for non-large-scale crops. In this paper, we propose an improved encoder-decoder framework based on DeepLab v3+ to accurately identify crops with different planting patterns. The network employs ShuffleNet v2 as the backbone to extract features at multiple levels. The decoder module integrates a convolutional block attention mechanism that combines both channel and spatial attention mechanisms to fuse attention features across the channel and spatial dimensions. We establish two datasets, DS1 and DS2, where DS1 is obtained from areas with large-scale crop planting, and DS2 is obtained from areas with scattered crop planting. On DS1, the improved network achieves a mean intersection over union (mIoU) of 0.972, overall accuracy (OA) of 0.981, and recall of 0.980, indicating a significant improvement of 7.0%, 5.0%, and 5.7%, respectively, compared to the original DeepLab v3+. On DS2, the improved network improves the mIoU, OA, and recall by 5.4%, 3.9%, and 4.4%, respectively. Notably, the number of parameters and giga floating-point operations (GFLOPs) required by the proposed Deep-agriNet is significantly smaller than that of DeepLab v3+ and other classic networks. Our findings demonstrate that Deep-agriNet performs better in identifying crops with different planting scales, and can serve as an effective tool for crop identification in various regions and countries.

8.
Zhongguo Zhong Yao Za Zhi ; 48(8): 2233-2240, 2023 Apr.
Artículo en Chino | MEDLINE | ID: mdl-37282911

RESUMEN

Regan Syrup has the effect of clearing heat, releasing exterior, benefiting pharynx and relieving cough, and previous phase Ⅱ clinical trial showed that the efficacy of Regan Syrup high-dose and low-dose groups was better than that of the placebo group, and there was no statistically significant difference in the safety between the three groups. The present study was conducted to further investigate the efficacy and safety of the recommended dose(20 mL) of Regan Syrup in the treatment of common cold(wind-heat syndrome). Patients who met the inclusion and exclusion criteria were selected and divided into the test group(Regan Syrup+Shufeng Jiedu Capsules placebo), positive drug group(Regan Syrup placebo+Shufeng Jiedu Capsules) and placebo group(Regan Syrup placebo+Shufeng Jiedu Capsules placebo) at a 1∶1∶1 using a block randomization method. The course of treatment was 3 days. A total of 119 subjects were included from six study centers, 39 in the test group, 40 in the positive drug group and 40 in the placebo group. The onset time of antipyretic effect was shorter in the test group than in the placebo group(P≤0.01) and the positive drug group, but the difference between the test group and the positive drug group was not significant. The test group was superior to the positive drug group in terms of fever resolution(P<0.05), and had a shorter onset time of fever resolution than the placebo group, but without obvious difference between the two groups. Compared to the positive drug group, the test group had shortened disappearance time of all symptoms(P≤0.000 1). In addition, the test group was better than the positive drug group and the placebo group in relieving symptoms of sore throat and fever(P<0.05), and in terms of clinical efficacy, the recovery rate of common cold(wind-heat syndrome) was improved in the test group compared to that in the placebo group(P<0.05). On the fourth day after treatment, the total TCM syndrome score in both test group and positive drug group was lower than that in the placebo group(P<0.05). There was no significant difference in the incidence of adverse events between three groups and none of them experienced any serious adverse events related to the study drug. The results indicated that Regan Syrup could shorten the onset time of antipyretic effect, reduce the time of fever resolution, alleviate the symptoms such as sore throat and fever caused by wind-heat cold, reduce the total score of Chinese medicine symptoms, and improve the clinical recovery rate with good safety.


Asunto(s)
Antipiréticos , Resfriado Común , Faringitis , Humanos , Antipiréticos/efectos adversos , Antipiréticos/uso terapéutico , Cápsulas , Resfriado Común/tratamiento farmacológico , Resfriado Común/diagnóstico , Método Doble Ciego , Fiebre/tratamiento farmacológico , Calor , Resultado del Tratamiento
10.
Front Oncol ; 13: 1193874, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37274294

RESUMEN

Background: The efficacy of induction chemotherapy (IC) for acute myeloid leukemia (AML) has improved significantly with the application of targeting drugs. Our previous study showed that a 4-day IC regimen of cyclophosphamide (CTX) and Ara-C [CA (4 + 3)] achieved similar complete remission (CR) rate (80%) compared with the traditional 7-day regimen, and the survival rate appeared to be better. Methods: In this pilot study, we further shortened the CA regimen to 3 days, added low-dose venetoclax (VEN, 200 mg/day) (VCA), and reported the efficacy and safety here. Results: Twenty-five newly diagnosed adult AML patients were enrolled in this study and evaluated for the remission rate after one cycle of the VCA regimen. The CR/Cri was 92%, and all these patients had undetectable minimal residual disease (MRD-). The estimated overall survival at 12 months was 79.3%. The median time for both platelet recovery and absolute neutrophil count recovery was 16 days, faster than that of traditional IC. Compared with the previous CA (4 + 3) regimen, a higher CR rate (92% vs. 80%, P < 0.01) and a deeper degree of remission (CRMRD- rate, 92% vs. 45%, P < 0.01) were found in the VCA group. Conclusions: This study showed that the 3-day CTX and Ara-C regimen is highly effective in newly diagnosed AML patients, and the addition of VEN to the CA regimen achieves higher and deeper one-course remission.

11.
Langmuir ; 39(20): 7143-7153, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37162499

RESUMEN

The viscoelasticity of wormlike micelles composed of ionic surfactants typically shows an exponential decrease with increasing temperature, which limits their application in relatively high-temperature (>90.0 °C) oilfields and the synthesis of functional materials as supramolecular templates at high temperatures. In this work, a series of imidazolium gemini surfactants, 1,9-(ethane-1,2-diyl)bis(3-alkyl-1H-imidazol-3-ium) bromide ([Cn-2-Cnim]Br2, n = 12, 14, 16, 18, 20), were synthesized. Their surface activities and aggregation behaviors in water were studied by electrical conductivity, rheology, polarization optical microscopy, small-angle X-ray scattering, ζ potential, and hydrogen nuclear magnetic resonance measurements. [C12-2-C12im]Br2 and [C14-2-C14im]Br2 mainly precipitate in water. [Cn-2-Cnim]Br2 (n = 16, 18, 20) forms lamellar liquid crystals over a large range of concentrations at low temperatures. With the increase of temperature, the lamellar liquid crystals transit to wormlike micelles. Interestingly, the viscoelasticity of the three wormlike micelles first increases to the maximum and then decreases with increasing temperature. These wormlike micelles without additives retain high viscoelasticity up to 90.0 °C or above. With the increase of the alkyl chain length of the surfactants, the transition temperature of lamellar liquid crystal to wormlike micelles and the disintegration temperature of wormlike micelles increase. The unusual increase of the viscoelasticity of wormlike micelles was due to the desorption of weakly bound counterions and the extension of the long hydrophobic chains of surfactants at high temperatures.

12.
Micromachines (Basel) ; 14(3)2023 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-36984923

RESUMEN

Piezoelectric micromechanical ultrasonic transducers (pMUTs) are new types of distance sensors with great potential for applications in automotive, unmanned aerial vehicle, robotics, and smart homes. However, previously reported pMUTs are limited by a short sensing distance due to lower output sound pressure. In this work, a pMUT with a special dual-ring structure based on scandium-doped aluminum nitride (ScAlN) is proposed. The combination of a dual-ring structure with pinned boundary conditions and a high piezoelectric performance ScAlN film allows the pMUT to achieve a large dynamic displacement of 2.87 µm/V and a high electromechanical coupling coefficient (kt2) of 8.92%. The results of ranging experiments show that a single pMUT achieves a distance sensing of 6 m at a resonant frequency of 91 kHz, the farthest distance sensing registered to date. This pMUT provides surprisingly fertile ground for various distance sensing applications.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 296: 122668, 2023 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-37001262

RESUMEN

Apple fruit damages seriously cause product and economic losses, infringe consumer rights and interests, and have harmful effects on human and livestock health. In this study, Raman spectroscopy (RS) and cascade forest (CForest) were adopted to determine apple fruit damages. First, the RS spectra of healthy, bruised, Rhizopus-infected, and Botrytis-infected apples were measured. Spectral changes and band attribution were analyzed. Different modeling methods were combined with various pre-processing and dimension reduction methods to construct recognition models. Among all models, CForest constructed with full spectra processed by Savitsky-Golay smoothing obtained the best performance with accuracies of 100%, 91.96%, and 92.80% in the training, validation, and test sets (ACCTE). And the modeling time is reduced to 1/3 of the full-spectra model with a similar ACCTE of 91.56% after principal component analysis. Overall, RS and CForest provided a non-destructive, rapid, and accurate identification of apple fruit damages and could be used in disease recognition and safety assurance of other fruits.


Asunto(s)
Frutas , Malus , Humanos , Frutas/química , Malus/química , Espectrometría Raman/métodos , Análisis de Componente Principal
14.
Front Plant Sci ; 14: 1091600, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36844049

RESUMEN

Diseases have a great impact on the quality and yield of strawberries, an accurate and timely field disease identification method is urgently needed. However, identifying diseases of strawberries in field is challenging due to the complex background interference and subtle inter-class differences. A feasible method to address the challenges is to segment strawberry lesions from the background and learn fine-grained features of the lesions. Following this idea, we present a novel Class-Attention-based Lesion Proposal Convolutional Neural Network (CALP-CNN), which utilizes a class response map to locate the main lesion object and propose discriminative lesion details. Specifically, the CALP-CNN firstly locates the main lesion object from the complex background through a class object location module (COLM) and then applies a lesion part proposal module (LPPM) to propose the discriminative lesion details. With a cascade architecture, the CALP-CNN can simultaneously address the interference from the complex background and the misclassification of similar diseases. A series of experiments on a self-built dataset of field strawberry diseases is conducted to testify the effectiveness of the proposed CALP-CNN. The classification results of the CALP-CNN are 92.56%, 92.55%, 91.80% and 91.96% on the metrics of accuracy, precision, recall and F1-score, respectively. Compared with six state-of-the-art attention-based fine-grained image recognition methods, the CALP-CNN achieves 6.52% higher (on F1-score) than the sub-optimal baseline MMAL-Net, suggesting that the proposed methods are effective in identifying strawberry diseases in the field.

15.
J Colloid Interface Sci ; 639: 454-463, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36827911

RESUMEN

HYPOTHESIS: Since lamellar liquid crystals (LLCS) could be used for lubrication, many LLCS systems have been constructed to improve lubrication performance. However, most studies focused on the LLCS of the water system, and its corrosiveness brought some limitations to its application. Therefore, it is necessary to construct a non-aqueous LLCS system with good lubrication and anti-corrosion properties to improve its applicability. EXPERIMENTS: Anionic surfactant dodecyl benzene sulfonic acid (DBSA) was used to construct non-aqueous LLCS in different solvents, including monoethanolamine (MEA) and diethanolamine (DEA). DBSA/H2O LLCS system was constructed for comparison. The LLCS was characterized by polarizing microscope (POM), small-angle X-ray scattering (SAXS), and rheology. Its microstructure was discussed. Meanwhile, we evaluated the lubrication and anti-corrosion performance of LLCS. Its lubrication mechanism was explained through tribology tests and X-ray photoelectron spectrometer (XPS) analysis of the wear scar surface. Its anti-corrosion mechanism was investigated by using the weightlessness method, electrochemical test method, and quantum chemical theoretical calculations. FINDINGS: The DBSA/MEA non-aqueous LLCS system showed better lubrication performance than DBSA/DEA and DBSA/H2O LLCS. It can adsorb on the surface of the friction pair to form a lubrication friction film, which plays a better role in reducing friction and wear. The DBSA/MEA LLCS is less corrosive to metals because it can effectively isolate oxygen and water in the air between friction pairs. Furthermore, the lone pair electrons in the 2p orbital of the N atom in the MEA molecule could coordinate with the 3d empty orbital of the Fe atom, forming a protective film on the metal surface, which plays a good anti-corrosion effect. This work not only enriched the study of non-aqueous LLCS but also expanded its potential applications in the field of lubrication.

16.
J Ethnopharmacol ; 308: 116258, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-36806347

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Restoring the mucus layer is a potential strategy for treating ulcerative colitis (UC). Previous studies reported that a Chinese medicine formula Shaoyao Decoction (SYD) effectively improved UC. However, the role and mechanism of SYD in restoring the mucus layer are still vague. AIM OF THE STUDY: This study aimed to research the therapeutical effects and unravel the involved mechanism of SYD on DSS-evoked UC. MATERIALS AND METHODS: First, the constituents of SYD were detected by UPLC-QTOF-MS/MS. Then, the DSS-induced UC model was introduced to investigate the pharmacologic action and molecular mechanism of SYD on UC. Pharmacodynamic indicators were assessed including body weight, colon length, ulcerations, disease activity index (DAI), inflammatory cytokines and histological parameters. To investigate the integrality and functions of the mucous layer, AB-PAS stain and UEA-1 stain were used to evaluate the completeness of mucous layer, as well as the maturation of goblet cells (GCs). The bacterial invasion was detected by fluorescence in situ hybridization. As to mechanism exploration, the expressions of Notch/Hes1 pathway were investigated by using agonists in lipopolysaccharides (LPS) -stimulated LS174T cell. RESULTS: After modeling in mice, SYD remarkedly ameliorated the symptoms of mouse colitis, the expression of pro-inflammatory factors declined, and increased IL-10 expression was observed in SYD-treated mice. Besides, SYD repaired the structure of the mucus layer and prevented bacterial invasion. Mechanism investigation discovered that SYD promoted GCs differentiation by inhibiting the Notch pathway, which was consistent with the results in LPS-challenged LS174 cell. CONCLUSIONS: These findings demonstrated that SYD could restore the mucus layer to prevent UC via suppressing the Notch signaling pathway, which provided evidences for the UC treatment of SYD in the clinic.


Asunto(s)
Colitis Ulcerosa , Colitis , Medicamentos Herbarios Chinos , Animales , Ratones , Espectrometría de Masas en Tándem , Lipopolisacáridos/farmacología , Hibridación Fluorescente in Situ , Medicamentos Herbarios Chinos/farmacología , Colitis/tratamiento farmacológico , Colitis Ulcerosa/tratamiento farmacológico , Colon , Transducción de Señal , Moco/metabolismo , Sulfato de Dextran , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad
17.
Dalton Trans ; 52(10): 3040-3051, 2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36779551

RESUMEN

In this study, flower-like porous iron doped bismuth oxybromide on porous activated carbon visible light catalysts (BiOBr/Fe@AC) were prepared by a reactive imidazole ionic liquid surfactant assisted solvothermal process. The morphologies, structures, optical properties and photocatalytic properties were investigated in detail. The morphology of the synthesized Fe doped BiOBr composites gradually changed from a regular spherical shape to a non-specific shape with the increase of the alkyl chain length of the ionic liquid surfactants. The photocurrent of BiOBr/Fe@AC composites is greatly influenced by the content of Fe, the type of carbon sphere and the size of the composites. The photocatalytic activity of the obtained BiOBr/Fe@AC composites was evaluated by the degradation of 2-chloroethyl sulfide (CEES) under visible light. The BiOBr/Fe@AC composites exhibited significantly enhanced photocatalytic performance compared to that of pure BiOBr and the 10.0% Fe doped BiOBr/Fe@AC composite displayed the highest photocatalytic activity. The main active species were determined to be holes and superoxide radicals by electron spin resonance (ESR) analysis and free radical trapping experiments. The introduction of iron can improve the separation and transfer rate of photoinduced charges. Carbon spheres can enhance light harvesting, improve electron transfer and increase the number of catalytic active sites. Iron and carbon embellishment is an effective strategy to enhance the photocatalytic efficiency of BiOBr. Finally, a possible photocatalytic mechanism of BiOBr/Fe@AC has been proposed.

18.
Org Biomol Chem ; 21(13): 2715-2719, 2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-36722919

RESUMEN

A method for the hydroalkynylation and catalytic cyclization reactions of hexadehydro-Diels-Alder-derived benzynes is described. Diethynylbenzene derivatives are generated in a one-step reaction via trimethylsilyl-alkyne groups with benzyne formed by heating the appropriate tetrayne substrate. Trimethyl(phenylethynyl)silane loses TMS and binds to the electron-deficient site on HDDA-derived benzynes, and then phenanthrene was synthesized under mild reaction conditions by transition-metal-free, base promoted intramolecular cyclization.

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 290: 122311, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36608516

RESUMEN

In this study, reflectance spectroscopy was used to achieve rapid and non-destructive detection of amylase activity and moisture content in rice. Since rice husk can interfere with spectral measurements, spectral data transformation was used to remove the husk interference. Reflectance spectra of rice were transformed by direct standardization, convolutional autoencoder network, and kernel regression (KR). Then, random frog and elliptical envelope were adopted to select effective wavelengths, and partial least squares regression (PLSR) and support vector regression were used to establish analysis models. The optimal transformation was from KR, and PLSR and effective wavelengths of the transformed spectra obtained excellent performance with coefficient of determination of test of 0.6987 and 0.8317 and root-mean-square error of test of 0.3359 and 2.2239, respectively. The result was better than that of the rice spectra and was close to that of the husked rice spectra. When the moisture content was integrated into the regression model of amylase activity, a better result was obtained. Thus, the proposed method can detect amylase activity and moisture content in rice accurately.


Asunto(s)
Oryza , Oryza/química , Espectroscopía Infrarroja Corta/métodos , Análisis de los Mínimos Cuadrados , Amilasas
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