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1.
Sci Rep ; 14(1): 16642, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39025995

RESUMO

Open-pit mine pavement dust dries and breaks easily. As such, a composite pavement dust suppressant with good wettability, moisturizing, coagulation, and antifreezing properties in winter was investigated. Monomer screening and orthogonal experiments were conducted, using evaporation rate, permeability rate, viscosity, and freezing point as evaluation indexes. Consequently, a dust suppressant solution is a mixture of glycerol (GLY), sodium dodecylbenzene sulfonate (SDBS), polyacrylamide (PAM), compound propylene glycol (PG), and potassium acetate (PA). The characteristics of the dust suppressant and its interaction mechanism with road dust were measured and analyzed. The results showed that the optimal ratio of the antifreeze-type composite dust suppressant is 3%GLY, 0.30%SDBS, 0.07% PAM, and 50%PG + 10%PA; the contact angle is 27.62°, which can effectively wet coal dust. Moreover, it easily forms hydrogen bonds with water molecules to release free -OH, which increases the oxygen-containing functional groups in the dust. The maximum viscosity is 25.4 mPa·s, and the hydrophobic groups adsorbed on the surface of the dust can condense and agglomerate the dust to form large particles, and effectively inhibit the occurrence of dust. It freezes at - 34.2 â„ƒ, resists a temperature of - 30 â„ƒ without freezing, and improves dust suppression efficiency and antifreezing effect in cold areas.

2.
Nanoscale ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39005077

RESUMO

The interlayer twist angle has a direct effect on exciton lifetimes in van der Waals heterostructures. At small angles, the interlayer and intralayer excitons in MoSe2/WS2 heterostructures are hybridized, resulting in hybridized excitons with long lifetimes and strong resonance. However, the study of twist-angle modulation of hybridized exciton lifetimes is still insufficient, leading to an unclear understanding of the mechanism through which the twist angle between layers influences the lifetime of hybridized excitons. Here, we observed the formation of hybridized excitons by constructing MoSe2/WS2 heterostructures with different twist angles. The exciton lifetime is found to increase from 0.5 ns to 3.3 ns when the twist angle is reduced from 12° to 1°. This work provides a new perspective on the modulation of the exciton lifetime, enabling further exploration in improving the efficiency of optoelectronic devices.

3.
Chem Biodivers ; : e202400596, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804585

RESUMO

Three polysaccharides, PTC, PTH, and PTB, were extracted from Pinellia ternata using three different extraction conditions: room temperature water, hot water, and 2 % Na2CO3 solution. PTC and PTH were composed of rhamnose, glucose, galactose, mannose, glucuronic acid, galacturonic acid, and arabinose, which combine to form complex structures. PTB was composed solely of glucose and rhamnose. Further analysis indicated that PTC and PTB exhibited triple-helix structures. PTC showed the highest scavenging capacity against DPPH, superoxide anion, and hydroxyl radicals, with half maximal inhibitory concentrations (IC50) of 1004.1, 1584.1, and 1584.1 µg/mL, respectively. Additionally, PTC, PTH, and PTB were subjected to sulfation, phosphorylation, and selenization, resulting in the production of nine derivates. The distinctive absorptive bands of these derivates were determined through infrared spectroscopy. Selenized and sulfated derivates have shown significant antitumor and immunoenhancing properties. Our findings revealed that at 400 µg/mL, the inhibition rate of selenated PTB on HeLa cells was 54.2 % and that on HepG2 cells was 43.1 %. Additionally, selenized PTC displayed significant immunoenhancing activity, with a proliferation rate of 63.7 % at 400 µg/mL in RAW264.7 cells. These results provide valuable evidence supporting the consideration of polysaccharides from Pinellia ternata as a potential candidate for the development of antineoplastic drugs.

4.
RSC Adv ; 14(18): 12265-12277, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38633487

RESUMO

Four distinct CeO2 catalysts featuring varied morphologies (nanorods, nanocubes, nanoparticles, and nano spindle-shaped) were synthesized through a hydrothermal process and subsequently employed in the oxidation of dichloromethane (DCM). The findings revealed that the nano spindle-shaped CeO2 exhibited exposure of crystal faces (111), demonstrating superior catalytic oxidation performance for DCM with a T90 of 337 °C and notably excellent low-temperature catalytic activity (T50 = 192 °C). The primary reaction products were identified as HCl and CO2. Through obvious characterizations, it showed that the excellent catalytic activity presented by CeO2-s catalyst might be related to the higher oxygen vacancy concentration, surface active oxygen content, and superior redox performance caused by specific exposed crystal planes. Meanwhile, CeO2-s catalyst owned outstanding stability, reusability, and water inactivation regeneration, which had tremendous potential in practical treatment.

5.
Acta Biomater ; 179: 300-312, 2024 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-38518865

RESUMO

Deep tissue bacterial infections, especially methicillin-resistant Staphylococcus aureus (MRSA) infections, pose challenges to clinical therapy due to their low debridement efficiency and relapsing. Molybdenum disulfide (MoS2) is used in the antibacterial field as a classic photothermal agent (NIR-I) with good biocompatibility. However, due to its limited NIR-I tissue penetration ability and single treatment mode, MoS2 has poor therapeutic effects on deep tissue infection. Herein, we prepared a defect-type hybrid 2H-MoS2 nanozyme (MoWS2) using hydrothermal method fabricate the MoWS2 composite, which is a new antibacterial strategy involving photothermal and enzyme catalysis, and further enhances the activity of the nanozyme through overheating. The regulation of 2H-MoS2 defects through tungsten ion doping endows MoWS2 with better near-infrared two-region absorption (NIR-II) and enzyme catalytic performance. Antibacterial activity experiments in vitro have shown that MoWS2 can achieve efficient bactericidal activity and biofilm clearance through hyperthermia and reactive oxygen species (ROS). Deep MRSA infection experiments have shown that MoWS2 rapidly removes bacteria from subcutaneous infected tissues through photothermal therapy (PTT) and chemodynamic therapy (CDT), accelerates the dissipation of abscesses, and promotes the healing of infected wounds. Additionally, the versatile treatment mode of MoWS2 was further confirmed through tissue sectioning and immunofluorescence staining analysis. Overall, these results provide a feasible approach for achieving efficient treatment of deep tissue infections through tungsten ion doping to regulate defective 2H-MoS2. STATEMENT OF SIGNIFICANCE: The photothermal effect of MoS2 nanosheets in the NIR-I (650-900 nm) window in anti-MRSA therapy is considered to be highly reliable and efficient in PTA. However, most of the developed PPT therapies or antimicrobial systems based on PTT therapies developed with 1T-MoS2 have in vivo sterilization temperatures of more than 55°C, which have the risk of damaging the normal tissues of the skin. In this study, we prepared W@MoS2 with a good photothermal effect (36.9%) in the NIR-II window and good peroxidase-like activity. The combined effect of PTT and CDT has a stronger bactericidal effect while avoiding high-temperature damage, which makes the W@MoS2 material more advantageous in terms of antimicrobial effect.


Assuntos
Antibacterianos , Staphylococcus aureus Resistente à Meticilina , Molibdênio , Infecções Estafilocócicas , Cicatrização , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Molibdênio/química , Molibdênio/farmacologia , Animais , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/patologia , Antibacterianos/farmacologia , Antibacterianos/química , Camundongos , Dissulfetos/química , Dissulfetos/farmacologia , Raios Infravermelhos , Biofilmes/efeitos dos fármacos , Terapia Fototérmica
6.
Polymers (Basel) ; 15(21)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37960000

RESUMO

Some photosensitive resins have poor mechanical properties after 3D printing. To overcome these limitations, a polyurethane acrylate oligomer (PUA) microsphere was prepared using the Pickering emulsion template method and ultraviolet (UV) curing technology in this paper. The prepared PUA microspheres were added to PUA-1,6-hexanediol diacrylate (HDDA) photosensitive resin system for digital light processing (DLP) 3D printing technology. The preparation process of PUA microspheres was discussed based on micromorphology, and it was found that the oil-water ratio of the Pickering emulsion and the emulsification speed had a certain effect on the microsphere size. As the oil-water ratio and the emulsification speed increased, the microsphere particle size decreased to a certain extent. Adding a suitable proportion of PUA microspheres to the photosensitive resin can improve the mechanical properties and thermal stability. When the modified photosensitive resin microsphere content was 0.5%, the tensile strength, elongation at break, bending strength, and initial thermal decomposition temperature were increased by 79.14%, 47.26%, 26.69%, and 10.65%, respectively, compared with the unmodified photosensitive resin. This study provides a new way to improve the mechanical properties of photosensitive resin 3D printing. The resin materials studied in this work have potential application value in the fields of ceramic 3D printing and dental temporary replacement materials.

7.
Int J Biol Macromol ; 253(Pt 3): 126950, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37729995

RESUMO

With the growing demand for wearable electronics, designing biocompatible hydrogels that combine self-repairability, wide operating temperature and precise sensing ability offers a promising scheme. Herein, by interpenetrating naturally derived carboxymethyl cellulose (CMC) into a polyvinyl alcohol (PVA) gel matrix, a novel hydrogel is successfully developed via simple coordination with calcium chloride (CaCl2). The chelation of CMC and Ca2+ is applied as a second crosslinking mechanism to stabilize the hydrogel at relatively high temperature (95 °C). In particular, it has unique heat-induced healing behavior and unexpected tunable stiffness & transparency. Like the sea cucumber, the gel can transform between a stiffened state and a relaxed state (nearly 23 times modulated stiffness from 453 to 20 kPa) which originates from the reconstruction of the crystallites. The adjustable transparency enables the hydrogel to become an excellent information hiding material. Due to the presence of Ca2+, the hydrogels show favorable conductivity, anti-freezing and long-term stability. Based on the advantages, a self-powered sensor, where chemical energy is converted to electrical energy, is assembled for human motion detection. The low-cost, environmentally friendly strategy, at the same time, complies to the "green" chemistry concept with the full employment of the biopolymers. Therefore, the proposed hydrogel is deemed to find potential use in wearable sensors.


Assuntos
Carboximetilcelulose Sódica , Temperatura Alta , Humanos , Álcool de Polivinil , Temperatura , Condutividade Elétrica , Hidrogéis
8.
Int J Biol Macromol ; 246: 125682, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37406910

RESUMO

The research of additive biomass flame retardants is becoming more and more popular. In this work, amino modified halloysite nanotubes (A-HNTs), chitosan (CS) and phytic acid (PA) were introduced into polyvinyl alcohol (PVA) matrix to construct PA/A-HNT/CS/PVA organic-inorganic composite film with hydrogen bond and covalent bond cross-linking network structure. Adding PA/A-HNT/CS can remarkably improve the mechanical strength, UV resistance and thermal stability of PVA film. Compared with control PVA film, the transmittance of composite film in ultraviolet region decreases from 90 % to <15 %, and the tensile strength raises from 19.8 MPa to 31.0 MPa. The thermal decomposition temperature of the composite film increases, the weight loss rate decreases obviously, and the carbon residue can reach 26 wt% at 700 °C. The limiting oxygen index increases from 18.5 % to 32.2 %. Furthermore, the addition of this flame-retardant system can obviously reduce the combustion intensity of PVA, and its flame-retardant grade can reach V-0. It is of great significance to expand the application of PVA and the development of biomass flame retardant.

9.
Front Pharmacol ; 14: 1147677, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324451

RESUMO

Background: The complexity and rapid progression of lesions in diabetic kidney disease pose significant challenges for clinical diagnosis and treatment. The advantages of Traditional Chinese Medicine (TCM) in diagnosing and treating this condition have gradually become evident. However, due to the disease's complexity and the individualized approach to diagnosis and treatment in Traditional Chinese Medicine, Traditional Chinese Medicine guidelines have limitations in guiding the treatment of diabetic kidney disease. Most medical knowledge is currently stored in the process of recording medical records, which hinders the understanding of diseases and the acquisition of diagnostic and treatment knowledge among young doctors. Consequently, there is a lack of sufficient clinical knowledge to support the diagnosis and treatment of diabetic kidney disease in Traditional Chinese Medicine. Objective: To build a comprehensive knowledge graph for the diagnosis and treatment of diabetic kidney disease in Traditional Chinese Medicine, utilizing clinical guidelines, consensus, and real-world clinical data. On this basis, the knowledge of Traditional Chinese Medicine diagnosis and treatment of diabetic kidney disease was systematically combed and mined. Methods: Normative guideline data and actual medical records were used to construct a knowledge graph of Traditional Chinese Medicine diagnosis and treatment for diabetic kidney disease and the results obtained by data mining techniques enrich the relational attributes. Neo4j graph database was used for knowledge storage, visual knowledge display, and semantic query. Utilizing multi-dimensional relations with hierarchical weights as the core, a reverse retrieval verification process is conducted to address the critical problems of diagnosis and treatment put forward by experts. Results: 903 nodes and 1670 relationships were constructed under nine concepts and 20 relationships. Preliminarily a knowledge graph for Traditional Chinese Medicine diagnosis and treatment of diabetic kidney disease was constructed. Based on the multi-dimensional relationships, the diagnosis and treatment questions proposed by experts were validated through multi-hop queries of the graphs. The results were confirmed by experts and showed good outcomes. Conclusion: This study systematically combed the Traditional Chinese Medicine diagnosis and treatment knowledge of diabetic kidney disease by constructing the knowledge graph. Furthermore, it effectively solved the problem of "knowledge island". Through visual display and semantic retrieval, the discovery and sharing of diagnosis and treatment knowledge of diabetic kidney disease were realized.

10.
Polymers (Basel) ; 15(9)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37177158

RESUMO

Organic-inorganic halide perovskite solar cells (PSCs) have attracted much attention in recent years due to their simple manufacturing process, low cost, and high efficiency. So far, all efficient organic-inorganic halide PSCs are mainly made of polycrystalline perovskite films. There are transmission barriers and high-density defects on the surface, interface, and grain boundary of the films. Among them, the deep-level traps caused by specific charged defects are the main non-radiative recombination centers, which is the most important factor in limiting the photoelectric conversion efficiency of PSCs devices to the Shockley-Queisser (S-Q) theoretical efficiency limit. Therefore, it is imperative to select appropriate passivation materials and passivation strategies to effectively eliminate defects in perovskite films to improve their photovoltaic performance and stability. There are various passivation strategies for different components of PSCs, including interface engineering, additive engineering, antisolvent engineering, dopant engineering, etc. In this review, we summarize a large number of defect passivation work to illustrate the latest progress of different types of passivators in regulating the morphology, grain boundary, grain size, charge recombination, and defect density of states of perovskite films. In addition, we discuss the inherent defects of key materials in carrier transporting layers and the corresponding passivation strategies to further optimize PSCs components. Finally, some perspectives on the opportunities and challenges of PSCs in future development are highlighted.

11.
Thorac Cancer ; 14(16): 1420-1429, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37102239

RESUMO

BACKGROUND: DNA damage repair is a crucial mechanism highly related to therapy resistance for various therapeutic strategies. Our previous results have shown that the degree of drug resistance in small-cell lung cancer (SCLC) cell lines was proportional to both the transcription and expression levels of Wee1, indicating that Wee1, an evolutionarily highly conserved kinase, plays a vital role in the therapeutic resistance of SCLC. In the present study, we aim to determine the nonclassical mechanism of Wee1 on DNA repair regulation. METHODS: Western blot was conducted to determine the mono-ubiquitination level of H2Bub. Comet assay was used to evaluate the degree of DNA damage. Immunofluorescence was conducted to determine the DNA repair markers. Co-immunoprecipitation was utilized to assess the potential interactions with H2BY37ph. MTT assays were used to evaluate the survival rates of SCLC cells. RESULTS: Overexpression of Wee1 increases the level of H2BK120ub and alleviates ionizing radiation (IR)-induced DNA damage in SCLC cells. Moreover, H2BK120ub is a crucial molecule in Wee1-mediated double-strain break (DSB) repair in SCLC cells. Mechanisms study indicated that H2BY37ph is involved in Wee1-mediated H2BK120ub through interaction with the E3 ubiquitin ligase RNF20-RNF40 complex and upregulates its phosphorylation, mutation of H2BY37 phosphorylation sites attenuated DSB repair and enhanced the sensitivity of IR-induced SCLC cell death. CONCLUSION: H2BY37ph produces crosstalk with H2BK120ub in an E3 ubiquitin ligase-dependent manner, promoting Wee1-mediated DSB repair in SCLC cells. This study clarifies the nonclassical mechanism of Wee1 regulation of DSB repair, which provides a theoretical basis for the clinical understanding of the regulatory network of Wee1 and its use as a target for overcoming multiple types of therapeutic resistance.


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Quebras de DNA de Cadeia Dupla , Fosforilação , Lisina/genética , Lisina/metabolismo , Histonas/metabolismo , Reparo do DNA , Carcinoma de Pequenas Células do Pulmão/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Neoplasias Pulmonares/genética , DNA/metabolismo , Linhagem Celular Tumoral , Proteínas Tirosina Quinases/genética , Proteínas de Ciclo Celular/genética
12.
bioRxiv ; 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36993346

RESUMO

Integrating information from the recent past is critical for guiding predictions and shaping behavior. The process of integrating information, such as tracking distance traveled or time elapsed, begins with establishing a starting point. Yet, the mechanisms by which neural circuits utilize relevant cues to initiate integration remain unknown. Our study sheds light on this question by identifying a subpopulation of CA1 pyramidal neurons called PyrDown. These neurons shut down their activity at the beginning of distance or time integration and then gradually ramp up their firing as the animal approaches the reward. PyrDown neurons provide a mechanism for representing integrated information through ramping activity, complementing the well-known place/time cells that respond to specific distances or time points. Our findings also reveal that parvalbumin inhibitory interneurons mediate the shutdown of PyrDown neurons, uncovering a circuit motif that enables the initiation of subsequent information integration to improve future predictions.

13.
Sci Total Environ ; 857(Pt 3): 159613, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36273562

RESUMO

The automated guided vehicle (AGV) is a piece of promising advanced transport equipment that has been widely used in flexible manufacturing systems to increase productivity and automation. Previous studies about the AGV focused on improving the capacities of perception, navigation, and anti-collision as well as reducing the transport time, cost, and distance, but insufficient attention was paid to the energy consumption (EC) reduction of AGV. The energy benchmark is recognised as an effective analytical methodology and management tool that can improve energy efficiency. Nonetheless, research on the energy benchmark for the AGV is lacking. To finish a transport task, many AGV path plans are feasible, and we develop an energy benchmark to evaluate each path plan and select the energy-saving one. We also establish a dynamic rating system of energy efficiency which is consistent with the energy-saving potentials of the transport task. The case study shows that the transport EC is reduced by 10.98 %, validating the proposed energy benchmark methodology. In addition, the effects of AGV path plans on the EC of machine tools at the workstations are analysed. Lastly, we explore the relationship between the energy efficiency of AGV path plans and the locations of workstations.


Assuntos
Benchmarking
14.
Front Plant Sci ; 13: 998911, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36204048

RESUMO

Forsythia suspensa is a famous ornamental and medicinal plant in Oleaceae. CCD family is involved in the synthesis of pigments, volatiles, strigolactones, and abscisic acid (ABA) in plants. In this study, the CCD family in F. suspensa was analyzed at the genome level. A total of 16 members of the CCD family were identified, which included 11 members of the carotenoid cleavage dioxygenases (CCD) subfamily and 5 members of the 9-cis epoxycarotenoid dioxygenases (NCED) subfamily. The expression analysis of different tissues demonstrated that three FsCCD1 genes might be involved in the synthesis of pigments and volatiles in flowers and fruits. Three CCD4 genes were effectively expressed in flowers, while only FsCCD4-3 was effectively expressed in fruits. Comparison of CCD4 between Osmanthus fragrans and F. suspensa showed that the structure of FsCCD4-1 is was comparable that of OfCCD4-1 protein, indicating that the protein might be performing, especially in catalyzing the synthesis of ß-ionone. However, further comparison of the upstream promoter regions showed that the proteins have major differences in the composition of cis-elements, which might be responsible for differences in ß-ionone content. On the other hand, four NCED genes were significantly up-regulated under cold stress while two were up-regulated in drought stress. The data showed that these genes might be involved in the synthesis of ABA. Taken together, our data improves understanding of the CCD family and provides key candidate genes associated with cold and drought stresses in F. suspensa.

15.
World J Surg Oncol ; 20(1): 222, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35778770

RESUMO

BACKGROUND: To investigate the prognostic significance of station 4R lymph node (LN) dissection in patients who underwent operations for right primary non-small cell lung cancer (NSCLC). METHODS: We performed a retrospective study involving patients with right primary NSCLC who received lobotomy or pneumonectomy with mediastinal LN dissection between January 2011 and December 2017. Propensity score matching was performed. Disease-free survival (DFS) and overall survival (OS) were compared between patients with and without station 4R dissection. RESULTS: Our study included 2070 patients, with 207 patients having no station 4R dissection (S4RD- group) and 1863 patients having station 4R dissection (S4RD+ group). The 4R LN metastasis rate was 13.4% (142/1748), higher than that for other mediastinal LN metastases. Compared with the S4RD- group, the S4RD+ group had higher 5-year DFS (48.1% vs. 39.1%, P = 0.009) and OS (54.4% vs. 42.8%, P = 0.025). Station 4R dissection was an independent risk factor for DFS (odds ratio, OR, 1.28, 95% confidence interval, CI, 1.08-1.64, P = 0.007) and OS (OR 1.31, 95% CI 1.04-1.63, P = 0.018). Patients with adjuvant chemotherapy had a better prognosis after station 4R dissection than those without adjuvant chemotherapy (57.4% vs. 52.3%, P = 0.006). The 5-year OS in the station 4R metastasis group was lower than that in the station 4R non-metastasis group (26.9% vs. 44.3%, P = 0.006) among N2 patients. The 5-year OS of the single-station 4R metastasis group was lower than that of the single-station 7 metastasis group (15.7% vs. 51.6%, P = 0.002). CONCLUSIONS: Station 4R metastasis was the highest among all the mediastinal station metastases in right primary NSCLC patients. Station 4R dissection can improve the prognosis and should be recommended as a routine procedure for these patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Neoplasias do Mediastino , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Neoplasias Pulmonares/patologia , Excisão de Linfonodo/métodos , Metástase Linfática , Neoplasias do Mediastino/cirurgia , Prognóstico , Estudos Retrospectivos
16.
Huan Jing Ke Xue ; 43(6): 3048-3057, 2022 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-35686774

RESUMO

To understand the pollution characteristics, spatial distribution characteristics, potential ecological risks, and sources of heavy metals in surface sediments of Dongjiang Lake, 12 surface sediment samples were collected from Dongjiang Lake. The contents of 20 heavy metals including Li, Be, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Ag, Cd, Cs, Ba, Pb, and U were analyzed in this study. The geo-accumulation index method and potential risk index method were used to evaluate the pollution degree and potential risks of heavy metals in sediments, and the correlation analysis and principal component analysis were used to trace the source of the primary heavy metals. The results showed that the average contents of ω(Cd)(2.25 mg·kg-1) and ω(As)(80.80 mg·kg-1) in heavy metals of Dongjiang Lake sediments were 21.2 times and 5.5 times the background value (0.11 mg·kg-1 and 14.7 mg·kg-1) of Hunan province. The overall spatial distribution of heavy metals was in the order of South>North>Central. The evaluation by the geo-accumulation index method showed that Cd was at the heavy pollution level, As and Se were at the moderate pollution level, Ag and Ga were at the light pollution level, and the other heavy metals were below the pollution standard. The evaluation by the potential risk index showed that all the surface sediments of Dongjiang Lake were at the high-risk level. The main environmental risk factor was Cd, which had an extremely high risk; the second was As, which had a medium risk; and the remaining heavy metals had no ecological risk.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Cádmio/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Lagos , Metais Pesados/análise , Medição de Risco , Poluentes Químicos da Água/análise
17.
Molecules ; 27(12)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35745013

RESUMO

Magnolia officinalis Rehd. et Wils. and Magnolia officinalis Rehd. et Wils. var. biloba Rehd. et Wils, as the legal botanical origins of Magnoliae Officinalis Cortex, are almost impossible to distinguish according to their appearance traits with respect to medicinal bark. The application of AFLP molecular markers for differentiating the two origins has not yet been successful. In this study, a combination of e-nose measurements, e-tongue measurements, and chemical analyses coupled with multiple-source data fusion was used to differentiate the two origins. Linear discriminant analysis (LDA) and quadratic discriminant analysis (QDA) were applied to compare the discrimination results. It was shown that the e-nose system presented a good discriminant ability with a low classification error for both LDA and QDA compared with e-tongue measurements and chemical analyses. In addition, the discriminating capacity of LDA for low-level fusion with original data, similar to a combined system, was superior or equal to that acquired individually with the three approaches. For mid-level fusion, the combination of different principals extracted by PCA and variables obtained on the basis of PLS-VIP exhibited an analogous discrimination ability for LDA (classification error 0.0%) and was significantly superior to QDA (classification error 1.67-3.33%). As a result, the combined e-nose, e-tongue, and chemical analysis approach proved to be a powerful tool for differentiating the two origins of Magnoliae Officinalis Cortex.


Assuntos
Magnolia , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Cromatografia Gasosa , Nariz Eletrônico , Magnolia/química , Língua
18.
Polymers (Basel) ; 14(9)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35566885

RESUMO

Natural hydrogels are growing in interest as a priority for wound healing. Plant polysaccharides have a variety of biological pharmacological activities, and chitosan hydrogels have proven strong antimicrobial effects, but hydrogels prepared with polysaccharides alone have certain deficiencies. Polysaccharides from flowers of Lonicera japonica Thunb. (LP) and the aerial parts of Mentha canadensis L. (MP) were extracted and oxidized by sodium periodate (NaIO4) and then cross-linked with oxidized-carboxymethylated chitosan (O-CCS) to develop oxidized plant- polysaccharides-chitosan hydrogels (OPHs). SEM observation showed that OPHs had porous interior structures with interconnecting pores. The OPHs showed good swelling, water-retention ability, blood coagulation, cytocompatibility properties, and low cytotoxicity (classed as grade 1 according to United States Pharmacopoeia), which met the requirements for wound dressings. Then the cutaneous wound-healing effect was evaluated in BALB/C mice model, after 7 days treatment, the wound-closure rate of OPHs groups were all greater than 50%, and after 14 days, all were greater than 90%, while the value of the control group was only 72.6%. Of them, OPH-2 and OPH-3 were more favorable to the wound-healing process, as the promotion was more significant. The plant polysaccharides and CS-based hydrogel should be a candidate for cutaneous wound dressings.

19.
RSC Adv ; 12(21): 13209-13219, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35520114

RESUMO

Porcine decellularized small intestine submucosa (SIS) is a collagen membrane, which offers great potential as an organic substrate template in mineralization processes due to its good biodegradability and biocompatibility. However, a long period of mineralization and low efficiency are apparent, and the mechanism of collagen fiber mineralization has often been neglected in the previous literature. Thus, in this paper, we present a novel model of biomimetic collagen mineralization which uses dopamine (DA) molecules with the activating and retouching function of SIS collagen membranes and regulating collagen mineralization to construct the structure of mineralized collagen hard tissues. The crystal biomimetic mineralization growth of calcium phosphate on membranes is studied in different solid-liquid interfaces with a double ion self-assembled diffusion system under the simulated physiological microenvironment. In the system, pDA@SIS membranes are used to control the concentration of Ca2+ and PO4 3- ionic diffusion to generate supersaturation reaction conditions in 1-14 days. The system can successfully obtain polycrystals with low crystallinity on the pDA-collagen complex template surface of collagen fibers and along the collagen fibers. It initiates a generalized bionic mineralization pathway which can reduce the nucleation interfacial energy to promote rapid hydroxyapatite (HAP) nucleation and crystallization and accelerate the rate of collagen fiber mineralization. The pDA@SIS mineralized collagen membrane shows good biocompatibility with 100% cellular activity in the CCK-8 test, which significantly improved the adhesion proliferation of MC3T3-E1 cells. The pDA-SIS collagen complex, as a new type of mineralization template, may propose a new collagen mineralization strategy to produce a mineralized pDA@SIS scaffold bone-like material for tissue engineering or can potentially be applied in bone repair and regeneration.

20.
Eur J Pharm Biopharm ; 174: 47-55, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35364257

RESUMO

Using small interfering RNA (siRNA) for the specific gene-silencing has been a novel therapeutic method for the treatment of incurable diseases such as malignancies. However, it remains a challenge whether siRNA can be safely and effectively delivered into target cells. Therefore, we synthesized fluorescent carbon dots (CDs) as a gene vector at the siRNA delivery system that induced efficient gene knockdown in vitro while binding aptamer AS1411 to resolve the difficulty in cell targeting. We found that CDs with adequate biocompatibility can improve the efficiency of cellular uptake of siRNA. CLSM and FCM results showed that CDs were mainly localized in the cytoplasm and emitted bright green fluorescence. In addition, the CD/siRNA delivery system mediated by the aptamer AS1411 effectively silenced the expression of Fragile X mental retardation protein (FMRP) and successfully inhibited the migration and invasive propensity of hepatocellular carcinoma (HCC) cells. In summary, we have synthesized a valuable siRNA delivery vector enabling not only bioimaging but also effective downregulation of gene expression, which is indicative of an efficient potential for gene delivery and therapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Nanoestruturas , Carbono/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Linhagem Celular Tumoral , Proteína do X Frágil da Deficiência Intelectual , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , RNA Interferente Pequeno/metabolismo
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